]> git.vpit.fr Git - perl/modules/re-engine-Hooks.git/blobdiff - src/5013009/regcomp.c
Remove the 5.13 development branch
[perl/modules/re-engine-Hooks.git] / src / 5013009 / regcomp.c
diff --git a/src/5013009/regcomp.c b/src/5013009/regcomp.c
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-/*    regcomp.c
- */
-
-/*
- * 'A fair jaw-cracker dwarf-language must be.'            --Samwise Gamgee
- *
- *     [p.285 of _The Lord of the Rings_, II/iii: "The Ring Goes South"]
- */
-
-/* This file contains functions for compiling a regular expression.  See
- * also regexec.c which funnily enough, contains functions for executing
- * a regular expression.
- *
- * This file is also copied at build time to ext/re/re_comp.c, where
- * it's built with -DPERL_EXT_RE_BUILD -DPERL_EXT_RE_DEBUG -DPERL_EXT.
- * This causes the main functions to be compiled under new names and with
- * debugging support added, which makes "use re 'debug'" work.
- */
-
-/* NOTE: this is derived from Henry Spencer's regexp code, and should not
- * confused with the original package (see point 3 below).  Thanks, Henry!
- */
-
-/* Additional note: this code is very heavily munged from Henry's version
- * in places.  In some spots I've traded clarity for efficiency, so don't
- * blame Henry for some of the lack of readability.
- */
-
-/* The names of the functions have been changed from regcomp and
- * regexec to pregcomp and pregexec in order to avoid conflicts
- * with the POSIX routines of the same names.
-*/
-
-#ifdef PERL_EXT_RE_BUILD
-#include "re_top.h"
-#endif
-
-/*
- * pregcomp and pregexec -- regsub and regerror are not used in perl
- *
- *     Copyright (c) 1986 by University of Toronto.
- *     Written by Henry Spencer.  Not derived from licensed software.
- *
- *     Permission is granted to anyone to use this software for any
- *     purpose on any computer system, and to redistribute it freely,
- *     subject to the following restrictions:
- *
- *     1. The author is not responsible for the consequences of use of
- *             this software, no matter how awful, even if they arise
- *             from defects in it.
- *
- *     2. The origin of this software must not be misrepresented, either
- *             by explicit claim or by omission.
- *
- *     3. Altered versions must be plainly marked as such, and must not
- *             be misrepresented as being the original software.
- *
- *
- ****    Alterations to Henry's code are...
- ****
- ****    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- ****    2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008
- ****    by Larry Wall and others
- ****
- ****    You may distribute under the terms of either the GNU General Public
- ****    License or the Artistic License, as specified in the README file.
-
- *
- * Beware that some of this code is subtly aware of the way operator
- * precedence is structured in regular expressions.  Serious changes in
- * regular-expression syntax might require a total rethink.
- */
-#include "EXTERN.h"
-#define PERL_IN_REGCOMP_C
-#include "perl.h"
-
-#ifndef PERL_IN_XSUB_RE
-#include "re_defs.h"
-#endif
-
-#define REG_COMP_C
-#ifdef PERL_IN_XSUB_RE
-#  include "re_comp.h"
-#else
-#  include "regcomp.h"
-#endif
-
-#include "dquote_static.c"
-
-#ifdef op
-#undef op
-#endif /* op */
-
-#ifdef MSDOS
-#  if defined(BUGGY_MSC6)
- /* MSC 6.00A breaks on op/regexp.t test 85 unless we turn this off */
-#    pragma optimize("a",off)
- /* But MSC 6.00A is happy with 'w', for aliases only across function calls*/
-#    pragma optimize("w",on )
-#  endif /* BUGGY_MSC6 */
-#endif /* MSDOS */
-
-#ifndef STATIC
-#define        STATIC  static
-#endif
-
-typedef struct RExC_state_t {
-    U32                flags;                  /* are we folding, multilining? */
-    char       *precomp;               /* uncompiled string. */
-    REGEXP     *rx_sv;                 /* The SV that is the regexp. */
-    regexp     *rx;                    /* perl core regexp structure */
-    regexp_internal    *rxi;           /* internal data for regexp object pprivate field */        
-    char       *start;                 /* Start of input for compile */
-    char       *end;                   /* End of input for compile */
-    char       *parse;                 /* Input-scan pointer. */
-    I32                whilem_seen;            /* number of WHILEM in this expr */
-    regnode    *emit_start;            /* Start of emitted-code area */
-    regnode    *emit_bound;            /* First regnode outside of the allocated space */
-    regnode    *emit;                  /* Code-emit pointer; &regdummy = don't = compiling */
-    I32                naughty;                /* How bad is this pattern? */
-    I32                sawback;                /* Did we see \1, ...? */
-    U32                seen;
-    I32                size;                   /* Code size. */
-    I32                npar;                   /* Capture buffer count, (OPEN). */
-    I32                cpar;                   /* Capture buffer count, (CLOSE). */
-    I32                nestroot;               /* root parens we are in - used by accept */
-    I32                extralen;
-    I32                seen_zerolen;
-    I32                seen_evals;
-    regnode    **open_parens;          /* pointers to open parens */
-    regnode    **close_parens;         /* pointers to close parens */
-    regnode    *opend;                 /* END node in program */
-    I32                utf8;           /* whether the pattern is utf8 or not */
-    I32                orig_utf8;      /* whether the pattern was originally in utf8 */
-                               /* XXX use this for future optimisation of case
-                                * where pattern must be upgraded to utf8. */
-    HV         *paren_names;           /* Paren names */
-    
-    regnode    **recurse;              /* Recurse regops */
-    I32                recurse_count;          /* Number of recurse regops */
-    I32                in_lookbehind;
-#if ADD_TO_REGEXEC
-    char       *starttry;              /* -Dr: where regtry was called. */
-#define RExC_starttry  (pRExC_state->starttry)
-#endif
-#ifdef DEBUGGING
-    const char  *lastparse;
-    I32         lastnum;
-    AV          *paren_name_list;       /* idx -> name */
-#define RExC_lastparse (pRExC_state->lastparse)
-#define RExC_lastnum   (pRExC_state->lastnum)
-#define RExC_paren_name_list    (pRExC_state->paren_name_list)
-#endif
-} RExC_state_t;
-
-#define RExC_flags     (pRExC_state->flags)
-#define RExC_precomp   (pRExC_state->precomp)
-#define RExC_rx_sv     (pRExC_state->rx_sv)
-#define RExC_rx                (pRExC_state->rx)
-#define RExC_rxi       (pRExC_state->rxi)
-#define RExC_start     (pRExC_state->start)
-#define RExC_end       (pRExC_state->end)
-#define RExC_parse     (pRExC_state->parse)
-#define RExC_whilem_seen       (pRExC_state->whilem_seen)
-#ifdef RE_TRACK_PATTERN_OFFSETS
-#define RExC_offsets   (pRExC_state->rxi->u.offsets) /* I am not like the others */
-#endif
-#define RExC_emit      (pRExC_state->emit)
-#define RExC_emit_start        (pRExC_state->emit_start)
-#define RExC_emit_bound        (pRExC_state->emit_bound)
-#define RExC_naughty   (pRExC_state->naughty)
-#define RExC_sawback   (pRExC_state->sawback)
-#define RExC_seen      (pRExC_state->seen)
-#define RExC_size      (pRExC_state->size)
-#define RExC_npar      (pRExC_state->npar)
-#define RExC_nestroot   (pRExC_state->nestroot)
-#define RExC_extralen  (pRExC_state->extralen)
-#define RExC_seen_zerolen      (pRExC_state->seen_zerolen)
-#define RExC_seen_evals        (pRExC_state->seen_evals)
-#define RExC_utf8      (pRExC_state->utf8)
-#define RExC_orig_utf8 (pRExC_state->orig_utf8)
-#define RExC_open_parens       (pRExC_state->open_parens)
-#define RExC_close_parens      (pRExC_state->close_parens)
-#define RExC_opend     (pRExC_state->opend)
-#define RExC_paren_names       (pRExC_state->paren_names)
-#define RExC_recurse   (pRExC_state->recurse)
-#define RExC_recurse_count     (pRExC_state->recurse_count)
-#define RExC_in_lookbehind     (pRExC_state->in_lookbehind)
-
-
-#define        ISMULT1(c)      ((c) == '*' || (c) == '+' || (c) == '?')
-#define        ISMULT2(s)      ((*s) == '*' || (*s) == '+' || (*s) == '?' || \
-       ((*s) == '{' && regcurly(s)))
-
-#ifdef SPSTART
-#undef SPSTART         /* dratted cpp namespace... */
-#endif
-/*
- * Flags to be passed up and down.
- */
-#define        WORST           0       /* Worst case. */
-#define        HASWIDTH        0x01    /* Known to match non-null strings. */
-
-/* Simple enough to be STAR/PLUS operand, in an EXACT node must be a single
- * character, and if utf8, must be invariant.  Note that this is not the same thing as REGNODE_SIMPLE */
-#define        SIMPLE          0x02
-#define        SPSTART         0x04    /* Starts with * or +. */
-#define TRYAGAIN       0x08    /* Weeded out a declaration. */
-#define POSTPONED      0x10    /* (?1),(?&name), (??{...}) or similar */
-
-#define REG_NODE_NUM(x) ((x) ? (int)((x)-RExC_emit_start) : -1)
-
-/* whether trie related optimizations are enabled */
-#if PERL_ENABLE_EXTENDED_TRIE_OPTIMISATION
-#define TRIE_STUDY_OPT
-#define FULL_TRIE_STUDY
-#define TRIE_STCLASS
-#endif
-
-
-
-#define PBYTE(u8str,paren) ((U8*)(u8str))[(paren) >> 3]
-#define PBITVAL(paren) (1 << ((paren) & 7))
-#define PAREN_TEST(u8str,paren) ( PBYTE(u8str,paren) & PBITVAL(paren))
-#define PAREN_SET(u8str,paren) PBYTE(u8str,paren) |= PBITVAL(paren)
-#define PAREN_UNSET(u8str,paren) PBYTE(u8str,paren) &= (~PBITVAL(paren))
-
-/* If not already in utf8, do a longjmp back to the beginning */
-#define UTF8_LONGJMP 42 /* Choose a value not likely to ever conflict */
-#define REQUIRE_UTF8   STMT_START {                                       \
-                                     if (! UTF) JMPENV_JUMP(UTF8_LONGJMP); \
-                        } STMT_END
-
-/* About scan_data_t.
-
-  During optimisation we recurse through the regexp program performing
-  various inplace (keyhole style) optimisations. In addition study_chunk
-  and scan_commit populate this data structure with information about
-  what strings MUST appear in the pattern. We look for the longest 
-  string that must appear at a fixed location, and we look for the
-  longest string that may appear at a floating location. So for instance
-  in the pattern:
-  
-    /FOO[xX]A.*B[xX]BAR/
-    
-  Both 'FOO' and 'A' are fixed strings. Both 'B' and 'BAR' are floating
-  strings (because they follow a .* construct). study_chunk will identify
-  both FOO and BAR as being the longest fixed and floating strings respectively.
-  
-  The strings can be composites, for instance
-  
-     /(f)(o)(o)/
-     
-  will result in a composite fixed substring 'foo'.
-  
-  For each string some basic information is maintained:
-  
-  - offset or min_offset
-    This is the position the string must appear at, or not before.
-    It also implicitly (when combined with minlenp) tells us how many
-    characters must match before the string we are searching for.
-    Likewise when combined with minlenp and the length of the string it
-    tells us how many characters must appear after the string we have 
-    found.
-  
-  - max_offset
-    Only used for floating strings. This is the rightmost point that
-    the string can appear at. If set to I32 max it indicates that the
-    string can occur infinitely far to the right.
-  
-  - minlenp
-    A pointer to the minimum length of the pattern that the string 
-    was found inside. This is important as in the case of positive 
-    lookahead or positive lookbehind we can have multiple patterns 
-    involved. Consider
-    
-    /(?=FOO).*F/
-    
-    The minimum length of the pattern overall is 3, the minimum length
-    of the lookahead part is 3, but the minimum length of the part that
-    will actually match is 1. So 'FOO's minimum length is 3, but the 
-    minimum length for the F is 1. This is important as the minimum length
-    is used to determine offsets in front of and behind the string being 
-    looked for.  Since strings can be composites this is the length of the
-    pattern at the time it was committed with a scan_commit. Note that
-    the length is calculated by study_chunk, so that the minimum lengths
-    are not known until the full pattern has been compiled, thus the 
-    pointer to the value.
-  
-  - lookbehind
-  
-    In the case of lookbehind the string being searched for can be
-    offset past the start point of the final matching string. 
-    If this value was just blithely removed from the min_offset it would
-    invalidate some of the calculations for how many chars must match
-    before or after (as they are derived from min_offset and minlen and
-    the length of the string being searched for). 
-    When the final pattern is compiled and the data is moved from the
-    scan_data_t structure into the regexp structure the information
-    about lookbehind is factored in, with the information that would 
-    have been lost precalculated in the end_shift field for the 
-    associated string.
-
-  The fields pos_min and pos_delta are used to store the minimum offset
-  and the delta to the maximum offset at the current point in the pattern.    
-
-*/
-
-typedef struct scan_data_t {
-    /*I32 len_min;      unused */
-    /*I32 len_delta;    unused */
-    I32 pos_min;
-    I32 pos_delta;
-    SV *last_found;
-    I32 last_end;          /* min value, <0 unless valid. */
-    I32 last_start_min;
-    I32 last_start_max;
-    SV **longest;          /* Either &l_fixed, or &l_float. */
-    SV *longest_fixed;      /* longest fixed string found in pattern */
-    I32 offset_fixed;       /* offset where it starts */
-    I32 *minlen_fixed;      /* pointer to the minlen relevant to the string */
-    I32 lookbehind_fixed;   /* is the position of the string modfied by LB */
-    SV *longest_float;      /* longest floating string found in pattern */
-    I32 offset_float_min;   /* earliest point in string it can appear */
-    I32 offset_float_max;   /* latest point in string it can appear */
-    I32 *minlen_float;      /* pointer to the minlen relevant to the string */
-    I32 lookbehind_float;   /* is the position of the string modified by LB */
-    I32 flags;
-    I32 whilem_c;
-    I32 *last_closep;
-    struct regnode_charclass_class *start_class;
-} scan_data_t;
-
-/*
- * Forward declarations for pregcomp()'s friends.
- */
-
-static const scan_data_t zero_scan_data =
-  { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 ,0};
-
-#define SF_BEFORE_EOL          (SF_BEFORE_SEOL|SF_BEFORE_MEOL)
-#define SF_BEFORE_SEOL         0x0001
-#define SF_BEFORE_MEOL         0x0002
-#define SF_FIX_BEFORE_EOL      (SF_FIX_BEFORE_SEOL|SF_FIX_BEFORE_MEOL)
-#define SF_FL_BEFORE_EOL       (SF_FL_BEFORE_SEOL|SF_FL_BEFORE_MEOL)
-
-#ifdef NO_UNARY_PLUS
-#  define SF_FIX_SHIFT_EOL     (0+2)
-#  define SF_FL_SHIFT_EOL              (0+4)
-#else
-#  define SF_FIX_SHIFT_EOL     (+2)
-#  define SF_FL_SHIFT_EOL              (+4)
-#endif
-
-#define SF_FIX_BEFORE_SEOL     (SF_BEFORE_SEOL << SF_FIX_SHIFT_EOL)
-#define SF_FIX_BEFORE_MEOL     (SF_BEFORE_MEOL << SF_FIX_SHIFT_EOL)
-
-#define SF_FL_BEFORE_SEOL      (SF_BEFORE_SEOL << SF_FL_SHIFT_EOL)
-#define SF_FL_BEFORE_MEOL      (SF_BEFORE_MEOL << SF_FL_SHIFT_EOL) /* 0x20 */
-#define SF_IS_INF              0x0040
-#define SF_HAS_PAR             0x0080
-#define SF_IN_PAR              0x0100
-#define SF_HAS_EVAL            0x0200
-#define SCF_DO_SUBSTR          0x0400
-#define SCF_DO_STCLASS_AND     0x0800
-#define SCF_DO_STCLASS_OR      0x1000
-#define SCF_DO_STCLASS         (SCF_DO_STCLASS_AND|SCF_DO_STCLASS_OR)
-#define SCF_WHILEM_VISITED_POS 0x2000
-
-#define SCF_TRIE_RESTUDY        0x4000 /* Do restudy? */
-#define SCF_SEEN_ACCEPT         0x8000 
-
-#define UTF cBOOL(RExC_utf8)
-#define LOC (get_regex_charset(RExC_flags) == REGEX_LOCALE_CHARSET)
-#define UNI_SEMANTICS (get_regex_charset(RExC_flags) == REGEX_UNICODE_CHARSET)
-#define DEPENDS_SEMANTICS (get_regex_charset(RExC_flags) == REGEX_DEPENDS_CHARSET)
-#define AT_LEAST_UNI_SEMANTICS (get_regex_charset(RExC_flags) >= REGEX_UNICODE_CHARSET)
-#define ASCII_RESTRICTED (get_regex_charset(RExC_flags) == REGEX_ASCII_RESTRICTED_CHARSET)
-
-#define FOLD cBOOL(RExC_flags & RXf_PMf_FOLD)
-
-#define OOB_UNICODE            12345678
-#define OOB_NAMEDCLASS         -1
-
-#define CHR_SVLEN(sv) (UTF ? sv_len_utf8(sv) : SvCUR(sv))
-#define CHR_DIST(a,b) (UTF ? utf8_distance(a,b) : a - b)
-
-
-/* length of regex to show in messages that don't mark a position within */
-#define RegexLengthToShowInErrorMessages 127
-
-/*
- * If MARKER[12] are adjusted, be sure to adjust the constants at the top
- * of t/op/regmesg.t, the tests in t/op/re_tests, and those in
- * op/pragma/warn/regcomp.
- */
-#define MARKER1 "<-- HERE"    /* marker as it appears in the description */
-#define MARKER2 " <-- HERE "  /* marker as it appears within the regex */
-
-#define REPORT_LOCATION " in regex; marked by " MARKER1 " in m/%.*s" MARKER2 "%s/"
-
-/*
- * Calls SAVEDESTRUCTOR_X if needed, then calls Perl_croak with the given
- * arg. Show regex, up to a maximum length. If it's too long, chop and add
- * "...".
- */
-#define _FAIL(code) STMT_START {                                       \
-    const char *ellipses = "";                                         \
-    IV len = RExC_end - RExC_precomp;                                  \
-                                                                       \
-    if (!SIZE_ONLY)                                                    \
-       SAVEDESTRUCTOR_X(clear_re,(void*)RExC_rx_sv);                   \
-    if (len > RegexLengthToShowInErrorMessages) {                      \
-       /* chop 10 shorter than the max, to ensure meaning of "..." */  \
-       len = RegexLengthToShowInErrorMessages - 10;                    \
-       ellipses = "...";                                               \
-    }                                                                  \
-    code;                                                               \
-} STMT_END
-
-#define        FAIL(msg) _FAIL(                            \
-    Perl_croak(aTHX_ "%s in regex m/%.*s%s/",      \
-           msg, (int)len, RExC_precomp, ellipses))
-
-#define        FAIL2(msg,arg) _FAIL(                       \
-    Perl_croak(aTHX_ msg " in regex m/%.*s%s/",            \
-           arg, (int)len, RExC_precomp, ellipses))
-
-/*
- * Simple_vFAIL -- like FAIL, but marks the current location in the scan
- */
-#define        Simple_vFAIL(m) STMT_START {                                    \
-    const IV offset = RExC_parse - RExC_precomp;                       \
-    Perl_croak(aTHX_ "%s" REPORT_LOCATION,                             \
-           m, (int)offset, RExC_precomp, RExC_precomp + offset);       \
-} STMT_END
-
-/*
- * Calls SAVEDESTRUCTOR_X if needed, then Simple_vFAIL()
- */
-#define        vFAIL(m) STMT_START {                           \
-    if (!SIZE_ONLY)                                    \
-       SAVEDESTRUCTOR_X(clear_re,(void*)RExC_rx_sv);   \
-    Simple_vFAIL(m);                                   \
-} STMT_END
-
-/*
- * Like Simple_vFAIL(), but accepts two arguments.
- */
-#define        Simple_vFAIL2(m,a1) STMT_START {                        \
-    const IV offset = RExC_parse - RExC_precomp;                       \
-    S_re_croak2(aTHX_ m, REPORT_LOCATION, a1,                  \
-           (int)offset, RExC_precomp, RExC_precomp + offset);  \
-} STMT_END
-
-/*
- * Calls SAVEDESTRUCTOR_X if needed, then Simple_vFAIL2().
- */
-#define        vFAIL2(m,a1) STMT_START {                       \
-    if (!SIZE_ONLY)                                    \
-       SAVEDESTRUCTOR_X(clear_re,(void*)RExC_rx_sv);   \
-    Simple_vFAIL2(m, a1);                              \
-} STMT_END
-
-
-/*
- * Like Simple_vFAIL(), but accepts three arguments.
- */
-#define        Simple_vFAIL3(m, a1, a2) STMT_START {                   \
-    const IV offset = RExC_parse - RExC_precomp;               \
-    S_re_croak2(aTHX_ m, REPORT_LOCATION, a1, a2,              \
-           (int)offset, RExC_precomp, RExC_precomp + offset);  \
-} STMT_END
-
-/*
- * Calls SAVEDESTRUCTOR_X if needed, then Simple_vFAIL3().
- */
-#define        vFAIL3(m,a1,a2) STMT_START {                    \
-    if (!SIZE_ONLY)                                    \
-       SAVEDESTRUCTOR_X(clear_re,(void*)RExC_rx_sv);   \
-    Simple_vFAIL3(m, a1, a2);                          \
-} STMT_END
-
-/*
- * Like Simple_vFAIL(), but accepts four arguments.
- */
-#define        Simple_vFAIL4(m, a1, a2, a3) STMT_START {               \
-    const IV offset = RExC_parse - RExC_precomp;               \
-    S_re_croak2(aTHX_ m, REPORT_LOCATION, a1, a2, a3,          \
-           (int)offset, RExC_precomp, RExC_precomp + offset);  \
-} STMT_END
-
-#define        ckWARNreg(loc,m) STMT_START {                                   \
-    const IV offset = loc - RExC_precomp;                              \
-    Perl_ck_warner(aTHX_ packWARN(WARN_REGEXP), m REPORT_LOCATION,     \
-           (int)offset, RExC_precomp, RExC_precomp + offset);          \
-} STMT_END
-
-#define        ckWARNregdep(loc,m) STMT_START {                                \
-    const IV offset = loc - RExC_precomp;                              \
-    Perl_ck_warner_d(aTHX_ packWARN2(WARN_DEPRECATED, WARN_REGEXP),    \
-           m REPORT_LOCATION,                                          \
-           (int)offset, RExC_precomp, RExC_precomp + offset);          \
-} STMT_END
-
-#define        ckWARN2reg(loc, m, a1) STMT_START {                             \
-    const IV offset = loc - RExC_precomp;                              \
-    Perl_ck_warner(aTHX_ packWARN(WARN_REGEXP), m REPORT_LOCATION,     \
-           a1, (int)offset, RExC_precomp, RExC_precomp + offset);      \
-} STMT_END
-
-#define        vWARN3(loc, m, a1, a2) STMT_START {                             \
-    const IV offset = loc - RExC_precomp;                              \
-    Perl_warner(aTHX_ packWARN(WARN_REGEXP), m REPORT_LOCATION,                \
-           a1, a2, (int)offset, RExC_precomp, RExC_precomp + offset);  \
-} STMT_END
-
-#define        ckWARN3reg(loc, m, a1, a2) STMT_START {                         \
-    const IV offset = loc - RExC_precomp;                              \
-    Perl_ck_warner(aTHX_ packWARN(WARN_REGEXP), m REPORT_LOCATION,     \
-           a1, a2, (int)offset, RExC_precomp, RExC_precomp + offset);  \
-} STMT_END
-
-#define        vWARN4(loc, m, a1, a2, a3) STMT_START {                         \
-    const IV offset = loc - RExC_precomp;                              \
-    Perl_warner(aTHX_ packWARN(WARN_REGEXP), m REPORT_LOCATION,                \
-           a1, a2, a3, (int)offset, RExC_precomp, RExC_precomp + offset); \
-} STMT_END
-
-#define        ckWARN4reg(loc, m, a1, a2, a3) STMT_START {                     \
-    const IV offset = loc - RExC_precomp;                              \
-    Perl_ck_warner(aTHX_ packWARN(WARN_REGEXP), m REPORT_LOCATION,     \
-           a1, a2, a3, (int)offset, RExC_precomp, RExC_precomp + offset); \
-} STMT_END
-
-#define        vWARN5(loc, m, a1, a2, a3, a4) STMT_START {                     \
-    const IV offset = loc - RExC_precomp;                              \
-    Perl_warner(aTHX_ packWARN(WARN_REGEXP), m REPORT_LOCATION,                \
-           a1, a2, a3, a4, (int)offset, RExC_precomp, RExC_precomp + offset); \
-} STMT_END
-
-
-/* Allow for side effects in s */
-#define REGC(c,s) STMT_START {                 \
-    if (!SIZE_ONLY) *(s) = (c); else (void)(s);        \
-} STMT_END
-
-/* Macros for recording node offsets.   20001227 mjd@plover.com 
- * Nodes are numbered 1, 2, 3, 4.  Node #n's position is recorded in
- * element 2*n-1 of the array.  Element #2n holds the byte length node #n.
- * Element 0 holds the number n.
- * Position is 1 indexed.
- */
-#ifndef RE_TRACK_PATTERN_OFFSETS
-#define Set_Node_Offset_To_R(node,byte)
-#define Set_Node_Offset(node,byte)
-#define Set_Cur_Node_Offset
-#define Set_Node_Length_To_R(node,len)
-#define Set_Node_Length(node,len)
-#define Set_Node_Cur_Length(node)
-#define Node_Offset(n) 
-#define Node_Length(n) 
-#define Set_Node_Offset_Length(node,offset,len)
-#define ProgLen(ri) ri->u.proglen
-#define SetProgLen(ri,x) ri->u.proglen = x
-#else
-#define ProgLen(ri) ri->u.offsets[0]
-#define SetProgLen(ri,x) ri->u.offsets[0] = x
-#define Set_Node_Offset_To_R(node,byte) STMT_START {                   \
-    if (! SIZE_ONLY) {                                                 \
-       MJD_OFFSET_DEBUG(("** (%d) offset of node %d is %d.\n",         \
-                   __LINE__, (int)(node), (int)(byte)));               \
-       if((node) < 0) {                                                \
-           Perl_croak(aTHX_ "value of node is %d in Offset macro", (int)(node)); \
-       } else {                                                        \
-           RExC_offsets[2*(node)-1] = (byte);                          \
-       }                                                               \
-    }                                                                  \
-} STMT_END
-
-#define Set_Node_Offset(node,byte) \
-    Set_Node_Offset_To_R((node)-RExC_emit_start, (byte)-RExC_start)
-#define Set_Cur_Node_Offset Set_Node_Offset(RExC_emit, RExC_parse)
-
-#define Set_Node_Length_To_R(node,len) STMT_START {                    \
-    if (! SIZE_ONLY) {                                                 \
-       MJD_OFFSET_DEBUG(("** (%d) size of node %d is %d.\n",           \
-               __LINE__, (int)(node), (int)(len)));                    \
-       if((node) < 0) {                                                \
-           Perl_croak(aTHX_ "value of node is %d in Length macro", (int)(node)); \
-       } else {                                                        \
-           RExC_offsets[2*(node)] = (len);                             \
-       }                                                               \
-    }                                                                  \
-} STMT_END
-
-#define Set_Node_Length(node,len) \
-    Set_Node_Length_To_R((node)-RExC_emit_start, len)
-#define Set_Cur_Node_Length(len) Set_Node_Length(RExC_emit, len)
-#define Set_Node_Cur_Length(node) \
-    Set_Node_Length(node, RExC_parse - parse_start)
-
-/* Get offsets and lengths */
-#define Node_Offset(n) (RExC_offsets[2*((n)-RExC_emit_start)-1])
-#define Node_Length(n) (RExC_offsets[2*((n)-RExC_emit_start)])
-
-#define Set_Node_Offset_Length(node,offset,len) STMT_START {   \
-    Set_Node_Offset_To_R((node)-RExC_emit_start, (offset));    \
-    Set_Node_Length_To_R((node)-RExC_emit_start, (len));       \
-} STMT_END
-#endif
-
-#if PERL_ENABLE_EXPERIMENTAL_REGEX_OPTIMISATIONS
-#define EXPERIMENTAL_INPLACESCAN
-#endif /*PERL_ENABLE_EXPERIMENTAL_REGEX_OPTIMISATIONS*/
-
-#define DEBUG_STUDYDATA(str,data,depth)                              \
-DEBUG_OPTIMISE_MORE_r(if(data){                                      \
-    PerlIO_printf(Perl_debug_log,                                    \
-        "%*s" str "Pos:%"IVdf"/%"IVdf                                \
-        " Flags: 0x%"UVXf" Whilem_c: %"IVdf" Lcp: %"IVdf" %s",       \
-        (int)(depth)*2, "",                                          \
-        (IV)((data)->pos_min),                                       \
-        (IV)((data)->pos_delta),                                     \
-        (UV)((data)->flags),                                         \
-        (IV)((data)->whilem_c),                                      \
-        (IV)((data)->last_closep ? *((data)->last_closep) : -1),     \
-        is_inf ? "INF " : ""                                         \
-    );                                                               \
-    if ((data)->last_found)                                          \
-        PerlIO_printf(Perl_debug_log,                                \
-            "Last:'%s' %"IVdf":%"IVdf"/%"IVdf" %sFixed:'%s' @ %"IVdf \
-            " %sFloat: '%s' @ %"IVdf"/%"IVdf"",                      \
-            SvPVX_const((data)->last_found),                         \
-            (IV)((data)->last_end),                                  \
-            (IV)((data)->last_start_min),                            \
-            (IV)((data)->last_start_max),                            \
-            ((data)->longest &&                                      \
-             (data)->longest==&((data)->longest_fixed)) ? "*" : "",  \
-            SvPVX_const((data)->longest_fixed),                      \
-            (IV)((data)->offset_fixed),                              \
-            ((data)->longest &&                                      \
-             (data)->longest==&((data)->longest_float)) ? "*" : "",  \
-            SvPVX_const((data)->longest_float),                      \
-            (IV)((data)->offset_float_min),                          \
-            (IV)((data)->offset_float_max)                           \
-        );                                                           \
-    PerlIO_printf(Perl_debug_log,"\n");                              \
-});
-
-static void clear_re(pTHX_ void *r);
-
-/* Mark that we cannot extend a found fixed substring at this point.
-   Update the longest found anchored substring and the longest found
-   floating substrings if needed. */
-
-STATIC void
-S_scan_commit(pTHX_ const RExC_state_t *pRExC_state, scan_data_t *data, I32 *minlenp, int is_inf)
-{
-    const STRLEN l = CHR_SVLEN(data->last_found);
-    const STRLEN old_l = CHR_SVLEN(*data->longest);
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_SCAN_COMMIT;
-
-    if ((l >= old_l) && ((l > old_l) || (data->flags & SF_BEFORE_EOL))) {
-       SvSetMagicSV(*data->longest, data->last_found);
-       if (*data->longest == data->longest_fixed) {
-           data->offset_fixed = l ? data->last_start_min : data->pos_min;
-           if (data->flags & SF_BEFORE_EOL)
-               data->flags
-                   |= ((data->flags & SF_BEFORE_EOL) << SF_FIX_SHIFT_EOL);
-           else
-               data->flags &= ~SF_FIX_BEFORE_EOL;
-           data->minlen_fixed=minlenp; 
-           data->lookbehind_fixed=0;
-       }
-       else { /* *data->longest == data->longest_float */
-           data->offset_float_min = l ? data->last_start_min : data->pos_min;
-           data->offset_float_max = (l
-                                     ? data->last_start_max
-                                     : data->pos_min + data->pos_delta);
-           if (is_inf || (U32)data->offset_float_max > (U32)I32_MAX)
-               data->offset_float_max = I32_MAX;
-           if (data->flags & SF_BEFORE_EOL)
-               data->flags
-                   |= ((data->flags & SF_BEFORE_EOL) << SF_FL_SHIFT_EOL);
-           else
-               data->flags &= ~SF_FL_BEFORE_EOL;
-            data->minlen_float=minlenp;
-            data->lookbehind_float=0;
-       }
-    }
-    SvCUR_set(data->last_found, 0);
-    {
-       SV * const sv = data->last_found;
-       if (SvUTF8(sv) && SvMAGICAL(sv)) {
-           MAGIC * const mg = mg_find(sv, PERL_MAGIC_utf8);
-           if (mg)
-               mg->mg_len = 0;
-       }
-    }
-    data->last_end = -1;
-    data->flags &= ~SF_BEFORE_EOL;
-    DEBUG_STUDYDATA("commit: ",data,0);
-}
-
-/* Can match anything (initialization) */
-STATIC void
-S_cl_anything(const RExC_state_t *pRExC_state, struct regnode_charclass_class *cl)
-{
-    PERL_ARGS_ASSERT_CL_ANYTHING;
-
-    ANYOF_CLASS_ZERO(cl);
-    ANYOF_BITMAP_SETALL(cl);
-    cl->flags = ANYOF_EOS|ANYOF_UNICODE_ALL|ANYOF_LOC_NONBITMAP_FOLD|ANYOF_NON_UTF8_LATIN1_ALL;
-    if (LOC)
-       cl->flags |= ANYOF_LOCALE;
-}
-
-/* Can match anything (initialization) */
-STATIC int
-S_cl_is_anything(const struct regnode_charclass_class *cl)
-{
-    int value;
-
-    PERL_ARGS_ASSERT_CL_IS_ANYTHING;
-
-    for (value = 0; value <= ANYOF_MAX; value += 2)
-       if (ANYOF_CLASS_TEST(cl, value) && ANYOF_CLASS_TEST(cl, value + 1))
-           return 1;
-    if (!(cl->flags & ANYOF_UNICODE_ALL))
-       return 0;
-    if (!ANYOF_BITMAP_TESTALLSET((const void*)cl))
-       return 0;
-    return 1;
-}
-
-/* Can match anything (initialization) */
-STATIC void
-S_cl_init(const RExC_state_t *pRExC_state, struct regnode_charclass_class *cl)
-{
-    PERL_ARGS_ASSERT_CL_INIT;
-
-    Zero(cl, 1, struct regnode_charclass_class);
-    cl->type = ANYOF;
-    cl_anything(pRExC_state, cl);
-}
-
-STATIC void
-S_cl_init_zero(const RExC_state_t *pRExC_state, struct regnode_charclass_class *cl)
-{
-    PERL_ARGS_ASSERT_CL_INIT_ZERO;
-
-    Zero(cl, 1, struct regnode_charclass_class);
-    cl->type = ANYOF;
-    cl_anything(pRExC_state, cl);
-    if (LOC)
-       cl->flags |= ANYOF_LOCALE;
-}
-
-/* 'And' a given class with another one.  Can create false positives */
-/* We assume that cl is not inverted */
-STATIC void
-S_cl_and(struct regnode_charclass_class *cl,
-       const struct regnode_charclass_class *and_with)
-{
-    PERL_ARGS_ASSERT_CL_AND;
-
-    assert(and_with->type == ANYOF);
-
-    if (!(ANYOF_CLASS_TEST_ANY_SET(and_with))
-       && !(ANYOF_CLASS_TEST_ANY_SET(cl))
-       && (and_with->flags & ANYOF_LOCALE) == (cl->flags & ANYOF_LOCALE)
-       && !(and_with->flags & ANYOF_LOC_NONBITMAP_FOLD)
-       && !(cl->flags & ANYOF_LOC_NONBITMAP_FOLD)) {
-       int i;
-
-       if (and_with->flags & ANYOF_INVERT)
-           for (i = 0; i < ANYOF_BITMAP_SIZE; i++)
-               cl->bitmap[i] &= ~and_with->bitmap[i];
-       else
-           for (i = 0; i < ANYOF_BITMAP_SIZE; i++)
-               cl->bitmap[i] &= and_with->bitmap[i];
-    } /* XXXX: logic is complicated otherwise, leave it along for a moment. */
-    if (!(and_with->flags & ANYOF_EOS))
-       cl->flags &= ~ANYOF_EOS;
-
-    if (!(and_with->flags & ANYOF_LOC_NONBITMAP_FOLD))
-       cl->flags &= ~ANYOF_LOC_NONBITMAP_FOLD;
-    if (!(and_with->flags & ANYOF_NON_UTF8_LATIN1_ALL))
-       cl->flags &= ~ANYOF_NON_UTF8_LATIN1_ALL;
-
-    if (cl->flags & ANYOF_UNICODE_ALL && and_with->flags & ANYOF_NONBITMAP &&
-       !(and_with->flags & ANYOF_INVERT)) {
-       cl->flags &= ~ANYOF_UNICODE_ALL;
-       cl->flags |= and_with->flags & ANYOF_NONBITMAP; /* field is 2 bits; use
-                                                          only the one(s)
-                                                          actually set */
-       ARG_SET(cl, ARG(and_with));
-    }
-    if (!(and_with->flags & ANYOF_UNICODE_ALL) &&
-       !(and_with->flags & ANYOF_INVERT))
-       cl->flags &= ~ANYOF_UNICODE_ALL;
-    if (!(and_with->flags & (ANYOF_NONBITMAP|ANYOF_UNICODE_ALL)) &&
-       !(and_with->flags & ANYOF_INVERT))
-       cl->flags &= ~ANYOF_NONBITMAP;
-}
-
-/* 'OR' a given class with another one.  Can create false positives */
-/* We assume that cl is not inverted */
-STATIC void
-S_cl_or(const RExC_state_t *pRExC_state, struct regnode_charclass_class *cl, const struct regnode_charclass_class *or_with)
-{
-    PERL_ARGS_ASSERT_CL_OR;
-
-    if (or_with->flags & ANYOF_INVERT) {
-       /* We do not use
-        * (B1 | CL1) | (!B2 & !CL2) = (B1 | !B2 & !CL2) | (CL1 | (!B2 & !CL2))
-        *   <= (B1 | !B2) | (CL1 | !CL2)
-        * which is wasteful if CL2 is small, but we ignore CL2:
-        *   (B1 | CL1) | (!B2 & !CL2) <= (B1 | CL1) | !B2 = (B1 | !B2) | CL1
-        * XXXX Can we handle case-fold?  Unclear:
-        *   (OK1(i) | OK1(i')) | !(OK1(i) | OK1(i')) =
-        *   (OK1(i) | OK1(i')) | (!OK1(i) & !OK1(i'))
-        */
-       if ( (or_with->flags & ANYOF_LOCALE) == (cl->flags & ANYOF_LOCALE)
-            && !(or_with->flags & ANYOF_LOC_NONBITMAP_FOLD)
-            && !(cl->flags & ANYOF_LOC_NONBITMAP_FOLD) ) {
-           int i;
-
-           for (i = 0; i < ANYOF_BITMAP_SIZE; i++)
-               cl->bitmap[i] |= ~or_with->bitmap[i];
-       } /* XXXX: logic is complicated otherwise */
-       else {
-           cl_anything(pRExC_state, cl);
-       }
-    } else {
-       /* (B1 | CL1) | (B2 | CL2) = (B1 | B2) | (CL1 | CL2)) */
-       if ( (or_with->flags & ANYOF_LOCALE) == (cl->flags & ANYOF_LOCALE)
-            && (!(or_with->flags & ANYOF_LOC_NONBITMAP_FOLD)
-                || (cl->flags & ANYOF_LOC_NONBITMAP_FOLD)) ) {
-           int i;
-
-           /* OR char bitmap and class bitmap separately */
-           for (i = 0; i < ANYOF_BITMAP_SIZE; i++)
-               cl->bitmap[i] |= or_with->bitmap[i];
-           if (ANYOF_CLASS_TEST_ANY_SET(or_with)) {
-               for (i = 0; i < ANYOF_CLASSBITMAP_SIZE; i++)
-                   cl->classflags[i] |= or_with->classflags[i];
-               cl->flags |= ANYOF_CLASS;
-           }
-       }
-       else { /* XXXX: logic is complicated, leave it along for a moment. */
-           cl_anything(pRExC_state, cl);
-       }
-    }
-    if (or_with->flags & ANYOF_EOS)
-       cl->flags |= ANYOF_EOS;
-    if (!(or_with->flags & ANYOF_NON_UTF8_LATIN1_ALL))
-       cl->flags |= ANYOF_NON_UTF8_LATIN1_ALL;
-
-    if (or_with->flags & ANYOF_LOC_NONBITMAP_FOLD)
-       cl->flags |= ANYOF_LOC_NONBITMAP_FOLD;
-
-    /* If both nodes match something outside the bitmap, but what they match
-     * outside is not the same pointer, and hence not easily compared, give up
-     * and allow the start class to match everything outside the bitmap */
-    if (cl->flags & ANYOF_NONBITMAP && or_with->flags & ANYOF_NONBITMAP &&
-       ARG(cl) != ARG(or_with)) {
-       cl->flags |= ANYOF_UNICODE_ALL;
-    }
-
-    if (or_with->flags & ANYOF_UNICODE_ALL) {
-       cl->flags |= ANYOF_UNICODE_ALL;
-    }
-}
-
-#define TRIE_LIST_ITEM(state,idx) (trie->states[state].trans.list)[ idx ]
-#define TRIE_LIST_CUR(state)  ( TRIE_LIST_ITEM( state, 0 ).forid )
-#define TRIE_LIST_LEN(state) ( TRIE_LIST_ITEM( state, 0 ).newstate )
-#define TRIE_LIST_USED(idx)  ( trie->states[state].trans.list ? (TRIE_LIST_CUR( idx ) - 1) : 0 )
-
-
-#ifdef DEBUGGING
-/*
-   dump_trie(trie,widecharmap,revcharmap)
-   dump_trie_interim_list(trie,widecharmap,revcharmap,next_alloc)
-   dump_trie_interim_table(trie,widecharmap,revcharmap,next_alloc)
-
-   These routines dump out a trie in a somewhat readable format.
-   The _interim_ variants are used for debugging the interim
-   tables that are used to generate the final compressed
-   representation which is what dump_trie expects.
-
-   Part of the reason for their existence is to provide a form
-   of documentation as to how the different representations function.
-
-*/
-
-/*
-  Dumps the final compressed table form of the trie to Perl_debug_log.
-  Used for debugging make_trie().
-*/
-
-STATIC void
-S_dump_trie(pTHX_ const struct _reg_trie_data *trie, HV *widecharmap,
-           AV *revcharmap, U32 depth)
-{
-    U32 state;
-    SV *sv=sv_newmortal();
-    int colwidth= widecharmap ? 6 : 4;
-    U16 word;
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_DUMP_TRIE;
-
-    PerlIO_printf( Perl_debug_log, "%*sChar : %-6s%-6s%-4s ",
-        (int)depth * 2 + 2,"",
-        "Match","Base","Ofs" );
-
-    for( state = 0 ; state < trie->uniquecharcount ; state++ ) {
-       SV ** const tmp = av_fetch( revcharmap, state, 0);
-        if ( tmp ) {
-            PerlIO_printf( Perl_debug_log, "%*s", 
-                colwidth,
-                pv_pretty(sv, SvPV_nolen_const(*tmp), SvCUR(*tmp), colwidth, 
-                           PL_colors[0], PL_colors[1],
-                           (SvUTF8(*tmp) ? PERL_PV_ESCAPE_UNI : 0) |
-                           PERL_PV_ESCAPE_FIRSTCHAR 
-                ) 
-            );
-        }
-    }
-    PerlIO_printf( Perl_debug_log, "\n%*sState|-----------------------",
-        (int)depth * 2 + 2,"");
-
-    for( state = 0 ; state < trie->uniquecharcount ; state++ )
-        PerlIO_printf( Perl_debug_log, "%.*s", colwidth, "--------");
-    PerlIO_printf( Perl_debug_log, "\n");
-
-    for( state = 1 ; state < trie->statecount ; state++ ) {
-       const U32 base = trie->states[ state ].trans.base;
-
-        PerlIO_printf( Perl_debug_log, "%*s#%4"UVXf"|", (int)depth * 2 + 2,"", (UV)state);
-
-        if ( trie->states[ state ].wordnum ) {
-            PerlIO_printf( Perl_debug_log, " W%4X", trie->states[ state ].wordnum );
-        } else {
-            PerlIO_printf( Perl_debug_log, "%6s", "" );
-        }
-
-        PerlIO_printf( Perl_debug_log, " @%4"UVXf" ", (UV)base );
-
-        if ( base ) {
-            U32 ofs = 0;
-
-            while( ( base + ofs  < trie->uniquecharcount ) ||
-                   ( base + ofs - trie->uniquecharcount < trie->lasttrans
-                     && trie->trans[ base + ofs - trie->uniquecharcount ].check != state))
-                    ofs++;
-
-            PerlIO_printf( Perl_debug_log, "+%2"UVXf"[ ", (UV)ofs);
-
-            for ( ofs = 0 ; ofs < trie->uniquecharcount ; ofs++ ) {
-                if ( ( base + ofs >= trie->uniquecharcount ) &&
-                     ( base + ofs - trie->uniquecharcount < trie->lasttrans ) &&
-                     trie->trans[ base + ofs - trie->uniquecharcount ].check == state )
-                {
-                   PerlIO_printf( Perl_debug_log, "%*"UVXf,
-                    colwidth,
-                    (UV)trie->trans[ base + ofs - trie->uniquecharcount ].next );
-                } else {
-                    PerlIO_printf( Perl_debug_log, "%*s",colwidth,"   ." );
-                }
-            }
-
-            PerlIO_printf( Perl_debug_log, "]");
-
-        }
-        PerlIO_printf( Perl_debug_log, "\n" );
-    }
-    PerlIO_printf(Perl_debug_log, "%*sword_info N:(prev,len)=", (int)depth*2, "");
-    for (word=1; word <= trie->wordcount; word++) {
-       PerlIO_printf(Perl_debug_log, " %d:(%d,%d)",
-           (int)word, (int)(trie->wordinfo[word].prev),
-           (int)(trie->wordinfo[word].len));
-    }
-    PerlIO_printf(Perl_debug_log, "\n" );
-}    
-/*
-  Dumps a fully constructed but uncompressed trie in list form.
-  List tries normally only are used for construction when the number of 
-  possible chars (trie->uniquecharcount) is very high.
-  Used for debugging make_trie().
-*/
-STATIC void
-S_dump_trie_interim_list(pTHX_ const struct _reg_trie_data *trie,
-                        HV *widecharmap, AV *revcharmap, U32 next_alloc,
-                        U32 depth)
-{
-    U32 state;
-    SV *sv=sv_newmortal();
-    int colwidth= widecharmap ? 6 : 4;
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_DUMP_TRIE_INTERIM_LIST;
-
-    /* print out the table precompression.  */
-    PerlIO_printf( Perl_debug_log, "%*sState :Word | Transition Data\n%*s%s",
-        (int)depth * 2 + 2,"", (int)depth * 2 + 2,"",
-        "------:-----+-----------------\n" );
-    
-    for( state=1 ; state < next_alloc ; state ++ ) {
-        U16 charid;
-    
-        PerlIO_printf( Perl_debug_log, "%*s %4"UVXf" :",
-            (int)depth * 2 + 2,"", (UV)state  );
-        if ( ! trie->states[ state ].wordnum ) {
-            PerlIO_printf( Perl_debug_log, "%5s| ","");
-        } else {
-            PerlIO_printf( Perl_debug_log, "W%4x| ",
-                trie->states[ state ].wordnum
-            );
-        }
-        for( charid = 1 ; charid <= TRIE_LIST_USED( state ) ; charid++ ) {
-           SV ** const tmp = av_fetch( revcharmap, TRIE_LIST_ITEM(state,charid).forid, 0);
-           if ( tmp ) {
-                PerlIO_printf( Perl_debug_log, "%*s:%3X=%4"UVXf" | ",
-                    colwidth,
-                    pv_pretty(sv, SvPV_nolen_const(*tmp), SvCUR(*tmp), colwidth, 
-                           PL_colors[0], PL_colors[1],
-                           (SvUTF8(*tmp) ? PERL_PV_ESCAPE_UNI : 0) |
-                           PERL_PV_ESCAPE_FIRSTCHAR 
-                    ) ,
-                    TRIE_LIST_ITEM(state,charid).forid,
-                    (UV)TRIE_LIST_ITEM(state,charid).newstate
-                );
-                if (!(charid % 10)) 
-                    PerlIO_printf(Perl_debug_log, "\n%*s| ",
-                        (int)((depth * 2) + 14), "");
-            }
-        }
-        PerlIO_printf( Perl_debug_log, "\n");
-    }
-}    
-
-/*
-  Dumps a fully constructed but uncompressed trie in table form.
-  This is the normal DFA style state transition table, with a few 
-  twists to facilitate compression later. 
-  Used for debugging make_trie().
-*/
-STATIC void
-S_dump_trie_interim_table(pTHX_ const struct _reg_trie_data *trie,
-                         HV *widecharmap, AV *revcharmap, U32 next_alloc,
-                         U32 depth)
-{
-    U32 state;
-    U16 charid;
-    SV *sv=sv_newmortal();
-    int colwidth= widecharmap ? 6 : 4;
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_DUMP_TRIE_INTERIM_TABLE;
-    
-    /*
-       print out the table precompression so that we can do a visual check
-       that they are identical.
-     */
-    
-    PerlIO_printf( Perl_debug_log, "%*sChar : ",(int)depth * 2 + 2,"" );
-
-    for( charid = 0 ; charid < trie->uniquecharcount ; charid++ ) {
-       SV ** const tmp = av_fetch( revcharmap, charid, 0);
-        if ( tmp ) {
-            PerlIO_printf( Perl_debug_log, "%*s", 
-                colwidth,
-                pv_pretty(sv, SvPV_nolen_const(*tmp), SvCUR(*tmp), colwidth, 
-                           PL_colors[0], PL_colors[1],
-                           (SvUTF8(*tmp) ? PERL_PV_ESCAPE_UNI : 0) |
-                           PERL_PV_ESCAPE_FIRSTCHAR 
-                ) 
-            );
-        }
-    }
-
-    PerlIO_printf( Perl_debug_log, "\n%*sState+-",(int)depth * 2 + 2,"" );
-
-    for( charid=0 ; charid < trie->uniquecharcount ; charid++ ) {
-        PerlIO_printf( Perl_debug_log, "%.*s", colwidth,"--------");
-    }
-
-    PerlIO_printf( Perl_debug_log, "\n" );
-
-    for( state=1 ; state < next_alloc ; state += trie->uniquecharcount ) {
-
-        PerlIO_printf( Perl_debug_log, "%*s%4"UVXf" : ", 
-            (int)depth * 2 + 2,"",
-            (UV)TRIE_NODENUM( state ) );
-
-        for( charid = 0 ; charid < trie->uniquecharcount ; charid++ ) {
-            UV v=(UV)SAFE_TRIE_NODENUM( trie->trans[ state + charid ].next );
-            if (v)
-                PerlIO_printf( Perl_debug_log, "%*"UVXf, colwidth, v );
-            else
-                PerlIO_printf( Perl_debug_log, "%*s", colwidth, "." );
-        }
-        if ( ! trie->states[ TRIE_NODENUM( state ) ].wordnum ) {
-            PerlIO_printf( Perl_debug_log, " (%4"UVXf")\n", (UV)trie->trans[ state ].check );
-        } else {
-            PerlIO_printf( Perl_debug_log, " (%4"UVXf") W%4X\n", (UV)trie->trans[ state ].check,
-            trie->states[ TRIE_NODENUM( state ) ].wordnum );
-        }
-    }
-}
-
-#endif
-
-
-/* make_trie(startbranch,first,last,tail,word_count,flags,depth)
-  startbranch: the first branch in the whole branch sequence
-  first      : start branch of sequence of branch-exact nodes.
-              May be the same as startbranch
-  last       : Thing following the last branch.
-              May be the same as tail.
-  tail       : item following the branch sequence
-  count      : words in the sequence
-  flags      : currently the OP() type we will be building one of /EXACT(|F|Fl)/
-  depth      : indent depth
-
-Inplace optimizes a sequence of 2 or more Branch-Exact nodes into a TRIE node.
-
-A trie is an N'ary tree where the branches are determined by digital
-decomposition of the key. IE, at the root node you look up the 1st character and
-follow that branch repeat until you find the end of the branches. Nodes can be
-marked as "accepting" meaning they represent a complete word. Eg:
-
-  /he|she|his|hers/
-
-would convert into the following structure. Numbers represent states, letters
-following numbers represent valid transitions on the letter from that state, if
-the number is in square brackets it represents an accepting state, otherwise it
-will be in parenthesis.
-
-      +-h->+-e->[3]-+-r->(8)-+-s->[9]
-      |    |
-      |   (2)
-      |    |
-     (1)   +-i->(6)-+-s->[7]
-      |
-      +-s->(3)-+-h->(4)-+-e->[5]
-
-      Accept Word Mapping: 3=>1 (he),5=>2 (she), 7=>3 (his), 9=>4 (hers)
-
-This shows that when matching against the string 'hers' we will begin at state 1
-read 'h' and move to state 2, read 'e' and move to state 3 which is accepting,
-then read 'r' and go to state 8 followed by 's' which takes us to state 9 which
-is also accepting. Thus we know that we can match both 'he' and 'hers' with a
-single traverse. We store a mapping from accepting to state to which word was
-matched, and then when we have multiple possibilities we try to complete the
-rest of the regex in the order in which they occured in the alternation.
-
-The only prior NFA like behaviour that would be changed by the TRIE support is
-the silent ignoring of duplicate alternations which are of the form:
-
- / (DUPE|DUPE) X? (?{ ... }) Y /x
-
-Thus EVAL blocks following a trie may be called a different number of times with
-and without the optimisation. With the optimisations dupes will be silently
-ignored. This inconsistent behaviour of EVAL type nodes is well established as
-the following demonstrates:
-
- 'words'=~/(word|word|word)(?{ print $1 })[xyz]/
-
-which prints out 'word' three times, but
-
- 'words'=~/(word|word|word)(?{ print $1 })S/
-
-which doesnt print it out at all. This is due to other optimisations kicking in.
-
-Example of what happens on a structural level:
-
-The regexp /(ac|ad|ab)+/ will produce the following debug output:
-
-   1: CURLYM[1] {1,32767}(18)
-   5:   BRANCH(8)
-   6:     EXACT <ac>(16)
-   8:   BRANCH(11)
-   9:     EXACT <ad>(16)
-  11:   BRANCH(14)
-  12:     EXACT <ab>(16)
-  16:   SUCCEED(0)
-  17:   NOTHING(18)
-  18: END(0)
-
-This would be optimizable with startbranch=5, first=5, last=16, tail=16
-and should turn into:
-
-   1: CURLYM[1] {1,32767}(18)
-   5:   TRIE(16)
-       [Words:3 Chars Stored:6 Unique Chars:4 States:5 NCP:1]
-         <ac>
-         <ad>
-         <ab>
-  16:   SUCCEED(0)
-  17:   NOTHING(18)
-  18: END(0)
-
-Cases where tail != last would be like /(?foo|bar)baz/:
-
-   1: BRANCH(4)
-   2:   EXACT <foo>(8)
-   4: BRANCH(7)
-   5:   EXACT <bar>(8)
-   7: TAIL(8)
-   8: EXACT <baz>(10)
-  10: END(0)
-
-which would be optimizable with startbranch=1, first=1, last=7, tail=8
-and would end up looking like:
-
-    1: TRIE(8)
-      [Words:2 Chars Stored:6 Unique Chars:5 States:7 NCP:1]
-       <foo>
-       <bar>
-   7: TAIL(8)
-   8: EXACT <baz>(10)
-  10: END(0)
-
-    d = uvuni_to_utf8_flags(d, uv, 0);
-
-is the recommended Unicode-aware way of saying
-
-    *(d++) = uv;
-*/
-
-#define TRIE_STORE_REVCHAR                                                 \
-    STMT_START {                                                           \
-       if (UTF) {                                                         \
-           SV *zlopp = newSV(2);                                          \
-           unsigned char *flrbbbbb = (unsigned char *) SvPVX(zlopp);      \
-           unsigned const char *const kapow = uvuni_to_utf8(flrbbbbb, uvc & 0xFF); \
-           SvCUR_set(zlopp, kapow - flrbbbbb);                            \
-           SvPOK_on(zlopp);                                               \
-           SvUTF8_on(zlopp);                                              \
-           av_push(revcharmap, zlopp);                                    \
-       } else {                                                           \
-           char ooooff = (char)uvc;                                               \
-           av_push(revcharmap, newSVpvn(&ooooff, 1));                     \
-       }                                                                  \
-        } STMT_END
-
-#define TRIE_READ_CHAR STMT_START {                                           \
-    wordlen++;                                                                \
-    if ( UTF ) {                                                              \
-       if ( folder ) {                                                       \
-           if ( foldlen > 0 ) {                                              \
-              uvc = utf8n_to_uvuni( scan, UTF8_MAXLEN, &len, uniflags );     \
-              foldlen -= len;                                                \
-              scan += len;                                                   \
-              len = 0;                                                       \
-           } else {                                                          \
-               uvc = utf8n_to_uvuni( (const U8*)uc, UTF8_MAXLEN, &len, uniflags);\
-               uvc = to_uni_fold( uvc, foldbuf, &foldlen );                  \
-               foldlen -= UNISKIP( uvc );                                    \
-               scan = foldbuf + UNISKIP( uvc );                              \
-           }                                                                 \
-       } else {                                                              \
-           uvc = utf8n_to_uvuni( (const U8*)uc, UTF8_MAXLEN, &len, uniflags);\
-       }                                                                     \
-    } else {                                                                  \
-       uvc = (U32)*uc;                                                       \
-       len = 1;                                                              \
-    }                                                                         \
-} STMT_END
-
-
-
-#define TRIE_LIST_PUSH(state,fid,ns) STMT_START {               \
-    if ( TRIE_LIST_CUR( state ) >=TRIE_LIST_LEN( state ) ) {    \
-       U32 ging = TRIE_LIST_LEN( state ) *= 2;                 \
-       Renew( trie->states[ state ].trans.list, ging, reg_trie_trans_le ); \
-    }                                                           \
-    TRIE_LIST_ITEM( state, TRIE_LIST_CUR( state ) ).forid = fid;     \
-    TRIE_LIST_ITEM( state, TRIE_LIST_CUR( state ) ).newstate = ns;   \
-    TRIE_LIST_CUR( state )++;                                   \
-} STMT_END
-
-#define TRIE_LIST_NEW(state) STMT_START {                       \
-    Newxz( trie->states[ state ].trans.list,               \
-       4, reg_trie_trans_le );                                 \
-     TRIE_LIST_CUR( state ) = 1;                                \
-     TRIE_LIST_LEN( state ) = 4;                                \
-} STMT_END
-
-#define TRIE_HANDLE_WORD(state) STMT_START {                    \
-    U16 dupe= trie->states[ state ].wordnum;                    \
-    regnode * const noper_next = regnext( noper );              \
-                                                                \
-    DEBUG_r({                                                   \
-        /* store the word for dumping */                        \
-        SV* tmp;                                                \
-        if (OP(noper) != NOTHING)                               \
-            tmp = newSVpvn_utf8(STRING(noper), STR_LEN(noper), UTF);   \
-        else                                                    \
-            tmp = newSVpvn_utf8( "", 0, UTF );                 \
-        av_push( trie_words, tmp );                             \
-    });                                                         \
-                                                                \
-    curword++;                                                  \
-    trie->wordinfo[curword].prev   = 0;                         \
-    trie->wordinfo[curword].len    = wordlen;                   \
-    trie->wordinfo[curword].accept = state;                     \
-                                                                \
-    if ( noper_next < tail ) {                                  \
-        if (!trie->jump)                                        \
-            trie->jump = (U16 *) PerlMemShared_calloc( word_count + 1, sizeof(U16) ); \
-        trie->jump[curword] = (U16)(noper_next - convert);      \
-        if (!jumper)                                            \
-            jumper = noper_next;                                \
-        if (!nextbranch)                                        \
-            nextbranch= regnext(cur);                           \
-    }                                                           \
-                                                                \
-    if ( dupe ) {                                               \
-        /* It's a dupe. Pre-insert into the wordinfo[].prev   */\
-        /* chain, so that when the bits of chain are later    */\
-        /* linked together, the dups appear in the chain      */\
-       trie->wordinfo[curword].prev = trie->wordinfo[dupe].prev; \
-       trie->wordinfo[dupe].prev = curword;                    \
-    } else {                                                    \
-        /* we haven't inserted this word yet.                */ \
-        trie->states[ state ].wordnum = curword;                \
-    }                                                           \
-} STMT_END
-
-
-#define TRIE_TRANS_STATE(state,base,ucharcount,charid,special)         \
-     ( ( base + charid >=  ucharcount                                  \
-         && base + charid < ubound                                     \
-         && state == trie->trans[ base - ucharcount + charid ].check   \
-         && trie->trans[ base - ucharcount + charid ].next )           \
-           ? trie->trans[ base - ucharcount + charid ].next            \
-           : ( state==1 ? special : 0 )                                        \
-      )
-
-#define MADE_TRIE       1
-#define MADE_JUMP_TRIE  2
-#define MADE_EXACT_TRIE 4
-
-STATIC I32
-S_make_trie(pTHX_ RExC_state_t *pRExC_state, regnode *startbranch, regnode *first, regnode *last, regnode *tail, U32 word_count, U32 flags, U32 depth)
-{
-    dVAR;
-    /* first pass, loop through and scan words */
-    reg_trie_data *trie;
-    HV *widecharmap = NULL;
-    AV *revcharmap = newAV();
-    regnode *cur;
-    const U32 uniflags = UTF8_ALLOW_DEFAULT;
-    STRLEN len = 0;
-    UV uvc = 0;
-    U16 curword = 0;
-    U32 next_alloc = 0;
-    regnode *jumper = NULL;
-    regnode *nextbranch = NULL;
-    regnode *convert = NULL;
-    U32 *prev_states; /* temp array mapping each state to previous one */
-    /* we just use folder as a flag in utf8 */
-    const U8 * folder = NULL;
-
-#ifdef DEBUGGING
-    const U32 data_slot = add_data( pRExC_state, 4, "tuuu" );
-    AV *trie_words = NULL;
-    /* along with revcharmap, this only used during construction but both are
-     * useful during debugging so we store them in the struct when debugging.
-     */
-#else
-    const U32 data_slot = add_data( pRExC_state, 2, "tu" );
-    STRLEN trie_charcount=0;
-#endif
-    SV *re_trie_maxbuff;
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_MAKE_TRIE;
-#ifndef DEBUGGING
-    PERL_UNUSED_ARG(depth);
-#endif
-
-    switch (flags) {
-       case EXACTFU: folder = PL_fold_latin1; break;
-       case EXACTF:  folder = PL_fold; break;
-       case EXACTFL: folder = PL_fold_locale; break;
-    }
-
-    trie = (reg_trie_data *) PerlMemShared_calloc( 1, sizeof(reg_trie_data) );
-    trie->refcount = 1;
-    trie->startstate = 1;
-    trie->wordcount = word_count;
-    RExC_rxi->data->data[ data_slot ] = (void*)trie;
-    trie->charmap = (U16 *) PerlMemShared_calloc( 256, sizeof(U16) );
-    if (!(UTF && folder))
-       trie->bitmap = (char *) PerlMemShared_calloc( ANYOF_BITMAP_SIZE, 1 );
-    trie->wordinfo = (reg_trie_wordinfo *) PerlMemShared_calloc(
-                       trie->wordcount+1, sizeof(reg_trie_wordinfo));
-
-    DEBUG_r({
-        trie_words = newAV();
-    });
-
-    re_trie_maxbuff = get_sv(RE_TRIE_MAXBUF_NAME, 1);
-    if (!SvIOK(re_trie_maxbuff)) {
-        sv_setiv(re_trie_maxbuff, RE_TRIE_MAXBUF_INIT);
-    }
-    DEBUG_OPTIMISE_r({
-                PerlIO_printf( Perl_debug_log,
-                  "%*smake_trie start==%d, first==%d, last==%d, tail==%d depth=%d\n",
-                  (int)depth * 2 + 2, "", 
-                  REG_NODE_NUM(startbranch),REG_NODE_NUM(first), 
-                  REG_NODE_NUM(last), REG_NODE_NUM(tail),
-                  (int)depth);
-    });
-   
-   /* Find the node we are going to overwrite */
-    if ( first == startbranch && OP( last ) != BRANCH ) {
-        /* whole branch chain */
-        convert = first;
-    } else {
-        /* branch sub-chain */
-        convert = NEXTOPER( first );
-    }
-        
-    /*  -- First loop and Setup --
-
-       We first traverse the branches and scan each word to determine if it
-       contains widechars, and how many unique chars there are, this is
-       important as we have to build a table with at least as many columns as we
-       have unique chars.
-
-       We use an array of integers to represent the character codes 0..255
-       (trie->charmap) and we use a an HV* to store Unicode characters. We use the
-       native representation of the character value as the key and IV's for the
-       coded index.
-
-       *TODO* If we keep track of how many times each character is used we can
-       remap the columns so that the table compression later on is more
-       efficient in terms of memory by ensuring the most common value is in the
-       middle and the least common are on the outside.  IMO this would be better
-       than a most to least common mapping as theres a decent chance the most
-       common letter will share a node with the least common, meaning the node
-       will not be compressible. With a middle is most common approach the worst
-       case is when we have the least common nodes twice.
-
-     */
-
-    for ( cur = first ; cur < last ; cur = regnext( cur ) ) {
-        regnode * const noper = NEXTOPER( cur );
-        const U8 *uc = (U8*)STRING( noper );
-        const U8 * const e  = uc + STR_LEN( noper );
-        STRLEN foldlen = 0;
-        U8 foldbuf[ UTF8_MAXBYTES_CASE + 1 ];
-        const U8 *scan = (U8*)NULL;
-        U32 wordlen      = 0;         /* required init */
-        STRLEN chars = 0;
-        bool set_bit = trie->bitmap ? 1 : 0; /*store the first char in the bitmap?*/
-
-        if (OP(noper) == NOTHING) {
-            trie->minlen= 0;
-            continue;
-        }
-        if ( set_bit ) /* bitmap only alloced when !(UTF&&Folding) */
-            TRIE_BITMAP_SET(trie,*uc); /* store the raw first byte
-                                          regardless of encoding */
-
-        for ( ; uc < e ; uc += len ) {
-            TRIE_CHARCOUNT(trie)++;
-            TRIE_READ_CHAR;
-            chars++;
-            if ( uvc < 256 ) {
-                if ( !trie->charmap[ uvc ] ) {
-                    trie->charmap[ uvc ]=( ++trie->uniquecharcount );
-                    if ( folder )
-                        trie->charmap[ folder[ uvc ] ] = trie->charmap[ uvc ];
-                    TRIE_STORE_REVCHAR;
-                }
-                if ( set_bit ) {
-                   /* store the codepoint in the bitmap, and its folded
-                    * equivalent. */
-                    TRIE_BITMAP_SET(trie,uvc);
-
-                   /* store the folded codepoint */
-                   if ( folder ) TRIE_BITMAP_SET(trie,folder[ uvc ]);
-
-                   if ( !UTF ) {
-                       /* store first byte of utf8 representation of
-                          variant codepoints */
-                       if (! UNI_IS_INVARIANT(uvc)) {
-                           TRIE_BITMAP_SET(trie, UTF8_TWO_BYTE_HI(uvc));
-                       }
-                   }
-                    set_bit = 0; /* We've done our bit :-) */
-                }
-            } else {
-                SV** svpp;
-                if ( !widecharmap )
-                    widecharmap = newHV();
-
-                svpp = hv_fetch( widecharmap, (char*)&uvc, sizeof( UV ), 1 );
-
-                if ( !svpp )
-                    Perl_croak( aTHX_ "error creating/fetching widecharmap entry for 0x%"UVXf, uvc );
-
-                if ( !SvTRUE( *svpp ) ) {
-                    sv_setiv( *svpp, ++trie->uniquecharcount );
-                    TRIE_STORE_REVCHAR;
-                }
-            }
-        }
-        if( cur == first ) {
-            trie->minlen=chars;
-            trie->maxlen=chars;
-        } else if (chars < trie->minlen) {
-            trie->minlen=chars;
-        } else if (chars > trie->maxlen) {
-            trie->maxlen=chars;
-        }
-
-    } /* end first pass */
-    DEBUG_TRIE_COMPILE_r(
-        PerlIO_printf( Perl_debug_log, "%*sTRIE(%s): W:%d C:%d Uq:%d Min:%d Max:%d\n",
-                (int)depth * 2 + 2,"",
-                ( widecharmap ? "UTF8" : "NATIVE" ), (int)word_count,
-               (int)TRIE_CHARCOUNT(trie), trie->uniquecharcount,
-               (int)trie->minlen, (int)trie->maxlen )
-    );
-
-    /*
-        We now know what we are dealing with in terms of unique chars and
-        string sizes so we can calculate how much memory a naive
-        representation using a flat table  will take. If it's over a reasonable
-        limit (as specified by ${^RE_TRIE_MAXBUF}) we use a more memory
-        conservative but potentially much slower representation using an array
-        of lists.
-
-        At the end we convert both representations into the same compressed
-        form that will be used in regexec.c for matching with. The latter
-        is a form that cannot be used to construct with but has memory
-        properties similar to the list form and access properties similar
-        to the table form making it both suitable for fast searches and
-        small enough that its feasable to store for the duration of a program.
-
-        See the comment in the code where the compressed table is produced
-        inplace from the flat tabe representation for an explanation of how
-        the compression works.
-
-    */
-
-
-    Newx(prev_states, TRIE_CHARCOUNT(trie) + 2, U32);
-    prev_states[1] = 0;
-
-    if ( (IV)( ( TRIE_CHARCOUNT(trie) + 1 ) * trie->uniquecharcount + 1) > SvIV(re_trie_maxbuff) ) {
-        /*
-            Second Pass -- Array Of Lists Representation
-
-            Each state will be represented by a list of charid:state records
-            (reg_trie_trans_le) the first such element holds the CUR and LEN
-            points of the allocated array. (See defines above).
-
-            We build the initial structure using the lists, and then convert
-            it into the compressed table form which allows faster lookups
-            (but cant be modified once converted).
-        */
-
-        STRLEN transcount = 1;
-
-        DEBUG_TRIE_COMPILE_MORE_r( PerlIO_printf( Perl_debug_log, 
-            "%*sCompiling trie using list compiler\n",
-            (int)depth * 2 + 2, ""));
-       
-       trie->states = (reg_trie_state *)
-           PerlMemShared_calloc( TRIE_CHARCOUNT(trie) + 2,
-                                 sizeof(reg_trie_state) );
-        TRIE_LIST_NEW(1);
-        next_alloc = 2;
-
-        for ( cur = first ; cur < last ; cur = regnext( cur ) ) {
-
-           regnode * const noper = NEXTOPER( cur );
-           U8 *uc           = (U8*)STRING( noper );
-           const U8 * const e = uc + STR_LEN( noper );
-           U32 state        = 1;         /* required init */
-           U16 charid       = 0;         /* sanity init */
-           U8 *scan         = (U8*)NULL; /* sanity init */
-           STRLEN foldlen   = 0;         /* required init */
-            U32 wordlen      = 0;         /* required init */
-           U8 foldbuf[ UTF8_MAXBYTES_CASE + 1 ];
-
-            if (OP(noper) != NOTHING) {
-                for ( ; uc < e ; uc += len ) {
-
-                    TRIE_READ_CHAR;
-
-                    if ( uvc < 256 ) {
-                        charid = trie->charmap[ uvc ];
-                   } else {
-                        SV** const svpp = hv_fetch( widecharmap, (char*)&uvc, sizeof( UV ), 0);
-                        if ( !svpp ) {
-                            charid = 0;
-                        } else {
-                            charid=(U16)SvIV( *svpp );
-                        }
-                   }
-                    /* charid is now 0 if we dont know the char read, or nonzero if we do */
-                    if ( charid ) {
-
-                        U16 check;
-                        U32 newstate = 0;
-
-                        charid--;
-                        if ( !trie->states[ state ].trans.list ) {
-                            TRIE_LIST_NEW( state );
-                       }
-                        for ( check = 1; check <= TRIE_LIST_USED( state ); check++ ) {
-                            if ( TRIE_LIST_ITEM( state, check ).forid == charid ) {
-                                newstate = TRIE_LIST_ITEM( state, check ).newstate;
-                                break;
-                            }
-                        }
-                        if ( ! newstate ) {
-                            newstate = next_alloc++;
-                           prev_states[newstate] = state;
-                            TRIE_LIST_PUSH( state, charid, newstate );
-                            transcount++;
-                        }
-                        state = newstate;
-                    } else {
-                        Perl_croak( aTHX_ "panic! In trie construction, no char mapping for %"IVdf, uvc );
-                   }
-               }
-           }
-            TRIE_HANDLE_WORD(state);
-
-        } /* end second pass */
-
-        /* next alloc is the NEXT state to be allocated */
-        trie->statecount = next_alloc; 
-        trie->states = (reg_trie_state *)
-           PerlMemShared_realloc( trie->states,
-                                  next_alloc
-                                  * sizeof(reg_trie_state) );
-
-        /* and now dump it out before we compress it */
-        DEBUG_TRIE_COMPILE_MORE_r(dump_trie_interim_list(trie, widecharmap,
-                                                        revcharmap, next_alloc,
-                                                        depth+1)
-        );
-
-        trie->trans = (reg_trie_trans *)
-           PerlMemShared_calloc( transcount, sizeof(reg_trie_trans) );
-        {
-            U32 state;
-            U32 tp = 0;
-            U32 zp = 0;
-
-
-            for( state=1 ; state < next_alloc ; state ++ ) {
-                U32 base=0;
-
-                /*
-                DEBUG_TRIE_COMPILE_MORE_r(
-                    PerlIO_printf( Perl_debug_log, "tp: %d zp: %d ",tp,zp)
-                );
-                */
-
-                if (trie->states[state].trans.list) {
-                    U16 minid=TRIE_LIST_ITEM( state, 1).forid;
-                    U16 maxid=minid;
-                   U16 idx;
-
-                    for( idx = 2 ; idx <= TRIE_LIST_USED( state ) ; idx++ ) {
-                       const U16 forid = TRIE_LIST_ITEM( state, idx).forid;
-                       if ( forid < minid ) {
-                           minid=forid;
-                       } else if ( forid > maxid ) {
-                           maxid=forid;
-                       }
-                    }
-                    if ( transcount < tp + maxid - minid + 1) {
-                        transcount *= 2;
-                       trie->trans = (reg_trie_trans *)
-                           PerlMemShared_realloc( trie->trans,
-                                                    transcount
-                                                    * sizeof(reg_trie_trans) );
-                        Zero( trie->trans + (transcount / 2), transcount / 2 , reg_trie_trans );
-                    }
-                    base = trie->uniquecharcount + tp - minid;
-                    if ( maxid == minid ) {
-                        U32 set = 0;
-                        for ( ; zp < tp ; zp++ ) {
-                            if ( ! trie->trans[ zp ].next ) {
-                                base = trie->uniquecharcount + zp - minid;
-                                trie->trans[ zp ].next = TRIE_LIST_ITEM( state, 1).newstate;
-                                trie->trans[ zp ].check = state;
-                                set = 1;
-                                break;
-                            }
-                        }
-                        if ( !set ) {
-                            trie->trans[ tp ].next = TRIE_LIST_ITEM( state, 1).newstate;
-                            trie->trans[ tp ].check = state;
-                            tp++;
-                            zp = tp;
-                        }
-                    } else {
-                        for ( idx=1; idx <= TRIE_LIST_USED( state ) ; idx++ ) {
-                            const U32 tid = base -  trie->uniquecharcount + TRIE_LIST_ITEM( state, idx ).forid;
-                            trie->trans[ tid ].next = TRIE_LIST_ITEM( state, idx ).newstate;
-                            trie->trans[ tid ].check = state;
-                        }
-                        tp += ( maxid - minid + 1 );
-                    }
-                    Safefree(trie->states[ state ].trans.list);
-                }
-                /*
-                DEBUG_TRIE_COMPILE_MORE_r(
-                    PerlIO_printf( Perl_debug_log, " base: %d\n",base);
-                );
-                */
-                trie->states[ state ].trans.base=base;
-            }
-            trie->lasttrans = tp + 1;
-        }
-    } else {
-        /*
-           Second Pass -- Flat Table Representation.
-
-           we dont use the 0 slot of either trans[] or states[] so we add 1 to each.
-           We know that we will need Charcount+1 trans at most to store the data
-           (one row per char at worst case) So we preallocate both structures
-           assuming worst case.
-
-           We then construct the trie using only the .next slots of the entry
-           structs.
-
-           We use the .check field of the first entry of the node temporarily to
-           make compression both faster and easier by keeping track of how many non
-           zero fields are in the node.
-
-           Since trans are numbered from 1 any 0 pointer in the table is a FAIL
-           transition.
-
-           There are two terms at use here: state as a TRIE_NODEIDX() which is a
-           number representing the first entry of the node, and state as a
-           TRIE_NODENUM() which is the trans number. state 1 is TRIE_NODEIDX(1) and
-           TRIE_NODENUM(1), state 2 is TRIE_NODEIDX(2) and TRIE_NODENUM(3) if there
-           are 2 entrys per node. eg:
-
-             A B       A B
-          1. 2 4    1. 3 7
-          2. 0 3    3. 0 5
-          3. 0 0    5. 0 0
-          4. 0 0    7. 0 0
-
-           The table is internally in the right hand, idx form. However as we also
-           have to deal with the states array which is indexed by nodenum we have to
-           use TRIE_NODENUM() to convert.
-
-        */
-        DEBUG_TRIE_COMPILE_MORE_r( PerlIO_printf( Perl_debug_log, 
-            "%*sCompiling trie using table compiler\n",
-            (int)depth * 2 + 2, ""));
-
-       trie->trans = (reg_trie_trans *)
-           PerlMemShared_calloc( ( TRIE_CHARCOUNT(trie) + 1 )
-                                 * trie->uniquecharcount + 1,
-                                 sizeof(reg_trie_trans) );
-        trie->states = (reg_trie_state *)
-           PerlMemShared_calloc( TRIE_CHARCOUNT(trie) + 2,
-                                 sizeof(reg_trie_state) );
-        next_alloc = trie->uniquecharcount + 1;
-
-
-        for ( cur = first ; cur < last ; cur = regnext( cur ) ) {
-
-           regnode * const noper   = NEXTOPER( cur );
-           const U8 *uc     = (U8*)STRING( noper );
-           const U8 * const e = uc + STR_LEN( noper );
-
-            U32 state        = 1;         /* required init */
-
-            U16 charid       = 0;         /* sanity init */
-            U32 accept_state = 0;         /* sanity init */
-            U8 *scan         = (U8*)NULL; /* sanity init */
-
-            STRLEN foldlen   = 0;         /* required init */
-            U32 wordlen      = 0;         /* required init */
-            U8 foldbuf[ UTF8_MAXBYTES_CASE + 1 ];
-
-            if ( OP(noper) != NOTHING ) {
-                for ( ; uc < e ; uc += len ) {
-
-                    TRIE_READ_CHAR;
-
-                    if ( uvc < 256 ) {
-                        charid = trie->charmap[ uvc ];
-                    } else {
-                        SV* const * const svpp = hv_fetch( widecharmap, (char*)&uvc, sizeof( UV ), 0);
-                        charid = svpp ? (U16)SvIV(*svpp) : 0;
-                    }
-                    if ( charid ) {
-                        charid--;
-                        if ( !trie->trans[ state + charid ].next ) {
-                            trie->trans[ state + charid ].next = next_alloc;
-                            trie->trans[ state ].check++;
-                           prev_states[TRIE_NODENUM(next_alloc)]
-                                   = TRIE_NODENUM(state);
-                            next_alloc += trie->uniquecharcount;
-                        }
-                        state = trie->trans[ state + charid ].next;
-                    } else {
-                        Perl_croak( aTHX_ "panic! In trie construction, no char mapping for %"IVdf, uvc );
-                    }
-                    /* charid is now 0 if we dont know the char read, or nonzero if we do */
-                }
-            }
-            accept_state = TRIE_NODENUM( state );
-            TRIE_HANDLE_WORD(accept_state);
-
-        } /* end second pass */
-
-        /* and now dump it out before we compress it */
-        DEBUG_TRIE_COMPILE_MORE_r(dump_trie_interim_table(trie, widecharmap,
-                                                         revcharmap,
-                                                         next_alloc, depth+1));
-
-        {
-        /*
-           * Inplace compress the table.*
-
-           For sparse data sets the table constructed by the trie algorithm will
-           be mostly 0/FAIL transitions or to put it another way mostly empty.
-           (Note that leaf nodes will not contain any transitions.)
-
-           This algorithm compresses the tables by eliminating most such
-           transitions, at the cost of a modest bit of extra work during lookup:
-
-           - Each states[] entry contains a .base field which indicates the
-           index in the state[] array wheres its transition data is stored.
-
-           - If .base is 0 there are no valid transitions from that node.
-
-           - If .base is nonzero then charid is added to it to find an entry in
-           the trans array.
-
-           -If trans[states[state].base+charid].check!=state then the
-           transition is taken to be a 0/Fail transition. Thus if there are fail
-           transitions at the front of the node then the .base offset will point
-           somewhere inside the previous nodes data (or maybe even into a node
-           even earlier), but the .check field determines if the transition is
-           valid.
-
-           XXX - wrong maybe?
-           The following process inplace converts the table to the compressed
-           table: We first do not compress the root node 1,and mark all its
-           .check pointers as 1 and set its .base pointer as 1 as well. This
-           allows us to do a DFA construction from the compressed table later,
-           and ensures that any .base pointers we calculate later are greater
-           than 0.
-
-           - We set 'pos' to indicate the first entry of the second node.
-
-           - We then iterate over the columns of the node, finding the first and
-           last used entry at l and m. We then copy l..m into pos..(pos+m-l),
-           and set the .check pointers accordingly, and advance pos
-           appropriately and repreat for the next node. Note that when we copy
-           the next pointers we have to convert them from the original
-           NODEIDX form to NODENUM form as the former is not valid post
-           compression.
-
-           - If a node has no transitions used we mark its base as 0 and do not
-           advance the pos pointer.
-
-           - If a node only has one transition we use a second pointer into the
-           structure to fill in allocated fail transitions from other states.
-           This pointer is independent of the main pointer and scans forward
-           looking for null transitions that are allocated to a state. When it
-           finds one it writes the single transition into the "hole".  If the
-           pointer doesnt find one the single transition is appended as normal.
-
-           - Once compressed we can Renew/realloc the structures to release the
-           excess space.
-
-           See "Table-Compression Methods" in sec 3.9 of the Red Dragon,
-           specifically Fig 3.47 and the associated pseudocode.
-
-           demq
-        */
-        const U32 laststate = TRIE_NODENUM( next_alloc );
-       U32 state, charid;
-        U32 pos = 0, zp=0;
-        trie->statecount = laststate;
-
-        for ( state = 1 ; state < laststate ; state++ ) {
-            U8 flag = 0;
-           const U32 stateidx = TRIE_NODEIDX( state );
-           const U32 o_used = trie->trans[ stateidx ].check;
-           U32 used = trie->trans[ stateidx ].check;
-            trie->trans[ stateidx ].check = 0;
-
-            for ( charid = 0 ; used && charid < trie->uniquecharcount ; charid++ ) {
-                if ( flag || trie->trans[ stateidx + charid ].next ) {
-                    if ( trie->trans[ stateidx + charid ].next ) {
-                        if (o_used == 1) {
-                            for ( ; zp < pos ; zp++ ) {
-                                if ( ! trie->trans[ zp ].next ) {
-                                    break;
-                                }
-                            }
-                            trie->states[ state ].trans.base = zp + trie->uniquecharcount - charid ;
-                            trie->trans[ zp ].next = SAFE_TRIE_NODENUM( trie->trans[ stateidx + charid ].next );
-                            trie->trans[ zp ].check = state;
-                            if ( ++zp > pos ) pos = zp;
-                            break;
-                        }
-                        used--;
-                    }
-                    if ( !flag ) {
-                        flag = 1;
-                        trie->states[ state ].trans.base = pos + trie->uniquecharcount - charid ;
-                    }
-                    trie->trans[ pos ].next = SAFE_TRIE_NODENUM( trie->trans[ stateidx + charid ].next );
-                    trie->trans[ pos ].check = state;
-                    pos++;
-                }
-            }
-        }
-        trie->lasttrans = pos + 1;
-        trie->states = (reg_trie_state *)
-           PerlMemShared_realloc( trie->states, laststate
-                                  * sizeof(reg_trie_state) );
-        DEBUG_TRIE_COMPILE_MORE_r(
-                PerlIO_printf( Perl_debug_log,
-                   "%*sAlloc: %d Orig: %"IVdf" elements, Final:%"IVdf". Savings of %%%5.2f\n",
-                   (int)depth * 2 + 2,"",
-                    (int)( ( TRIE_CHARCOUNT(trie) + 1 ) * trie->uniquecharcount + 1 ),
-                   (IV)next_alloc,
-                   (IV)pos,
-                    ( ( next_alloc - pos ) * 100 ) / (double)next_alloc );
-            );
-
-        } /* end table compress */
-    }
-    DEBUG_TRIE_COMPILE_MORE_r(
-            PerlIO_printf(Perl_debug_log, "%*sStatecount:%"UVxf" Lasttrans:%"UVxf"\n",
-                (int)depth * 2 + 2, "",
-                (UV)trie->statecount,
-                (UV)trie->lasttrans)
-    );
-    /* resize the trans array to remove unused space */
-    trie->trans = (reg_trie_trans *)
-       PerlMemShared_realloc( trie->trans, trie->lasttrans
-                              * sizeof(reg_trie_trans) );
-
-    {   /* Modify the program and insert the new TRIE node */ 
-        U8 nodetype =(U8)(flags & 0xFF);
-        char *str=NULL;
-        
-#ifdef DEBUGGING
-        regnode *optimize = NULL;
-#ifdef RE_TRACK_PATTERN_OFFSETS
-
-        U32 mjd_offset = 0;
-        U32 mjd_nodelen = 0;
-#endif /* RE_TRACK_PATTERN_OFFSETS */
-#endif /* DEBUGGING */
-        /*
-           This means we convert either the first branch or the first Exact,
-           depending on whether the thing following (in 'last') is a branch
-           or not and whther first is the startbranch (ie is it a sub part of
-           the alternation or is it the whole thing.)
-           Assuming its a sub part we convert the EXACT otherwise we convert
-           the whole branch sequence, including the first.
-         */
-        /* Find the node we are going to overwrite */
-        if ( first != startbranch || OP( last ) == BRANCH ) {
-            /* branch sub-chain */
-            NEXT_OFF( first ) = (U16)(last - first);
-#ifdef RE_TRACK_PATTERN_OFFSETS
-            DEBUG_r({
-                mjd_offset= Node_Offset((convert));
-                mjd_nodelen= Node_Length((convert));
-            });
-#endif
-            /* whole branch chain */
-        }
-#ifdef RE_TRACK_PATTERN_OFFSETS
-        else {
-            DEBUG_r({
-                const  regnode *nop = NEXTOPER( convert );
-                mjd_offset= Node_Offset((nop));
-                mjd_nodelen= Node_Length((nop));
-            });
-        }
-        DEBUG_OPTIMISE_r(
-            PerlIO_printf(Perl_debug_log, "%*sMJD offset:%"UVuf" MJD length:%"UVuf"\n",
-                (int)depth * 2 + 2, "",
-                (UV)mjd_offset, (UV)mjd_nodelen)
-        );
-#endif
-        /* But first we check to see if there is a common prefix we can 
-           split out as an EXACT and put in front of the TRIE node.  */
-        trie->startstate= 1;
-        if ( trie->bitmap && !widecharmap && !trie->jump  ) {
-            U32 state;
-            for ( state = 1 ; state < trie->statecount-1 ; state++ ) {
-                U32 ofs = 0;
-                I32 idx = -1;
-                U32 count = 0;
-                const U32 base = trie->states[ state ].trans.base;
-
-                if ( trie->states[state].wordnum )
-                        count = 1;
-
-                for ( ofs = 0 ; ofs < trie->uniquecharcount ; ofs++ ) {
-                    if ( ( base + ofs >= trie->uniquecharcount ) &&
-                         ( base + ofs - trie->uniquecharcount < trie->lasttrans ) &&
-                         trie->trans[ base + ofs - trie->uniquecharcount ].check == state )
-                    {
-                        if ( ++count > 1 ) {
-                            SV **tmp = av_fetch( revcharmap, ofs, 0);
-                           const U8 *ch = (U8*)SvPV_nolen_const( *tmp );
-                            if ( state == 1 ) break;
-                            if ( count == 2 ) {
-                                Zero(trie->bitmap, ANYOF_BITMAP_SIZE, char);
-                                DEBUG_OPTIMISE_r(
-                                    PerlIO_printf(Perl_debug_log,
-                                       "%*sNew Start State=%"UVuf" Class: [",
-                                        (int)depth * 2 + 2, "",
-                                        (UV)state));
-                               if (idx >= 0) {
-                                   SV ** const tmp = av_fetch( revcharmap, idx, 0);
-                                   const U8 * const ch = (U8*)SvPV_nolen_const( *tmp );
-
-                                    TRIE_BITMAP_SET(trie,*ch);
-                                    if ( folder )
-                                        TRIE_BITMAP_SET(trie, folder[ *ch ]);
-                                    DEBUG_OPTIMISE_r(
-                                        PerlIO_printf(Perl_debug_log, "%s", (char*)ch)
-                                    );
-                               }
-                           }
-                           TRIE_BITMAP_SET(trie,*ch);
-                           if ( folder )
-                               TRIE_BITMAP_SET(trie,folder[ *ch ]);
-                           DEBUG_OPTIMISE_r(PerlIO_printf( Perl_debug_log,"%s", ch));
-                       }
-                        idx = ofs;
-                   }
-                }
-                if ( count == 1 ) {
-                    SV **tmp = av_fetch( revcharmap, idx, 0);
-                    STRLEN len;
-                    char *ch = SvPV( *tmp, len );
-                    DEBUG_OPTIMISE_r({
-                        SV *sv=sv_newmortal();
-                        PerlIO_printf( Perl_debug_log,
-                           "%*sPrefix State: %"UVuf" Idx:%"UVuf" Char='%s'\n",
-                            (int)depth * 2 + 2, "",
-                            (UV)state, (UV)idx, 
-                            pv_pretty(sv, SvPV_nolen_const(*tmp), SvCUR(*tmp), 6, 
-                               PL_colors[0], PL_colors[1],
-                               (SvUTF8(*tmp) ? PERL_PV_ESCAPE_UNI : 0) |
-                               PERL_PV_ESCAPE_FIRSTCHAR 
-                            )
-                        );
-                    });
-                    if ( state==1 ) {
-                        OP( convert ) = nodetype;
-                        str=STRING(convert);
-                        STR_LEN(convert)=0;
-                    }
-                    STR_LEN(convert) += len;
-                    while (len--)
-                        *str++ = *ch++;
-               } else {
-#ifdef DEBUGGING           
-                   if (state>1)
-                       DEBUG_OPTIMISE_r(PerlIO_printf( Perl_debug_log,"]\n"));
-#endif
-                   break;
-               }
-           }
-           trie->prefixlen = (state-1);
-            if (str) {
-                regnode *n = convert+NODE_SZ_STR(convert);
-                NEXT_OFF(convert) = NODE_SZ_STR(convert);
-                trie->startstate = state;
-                trie->minlen -= (state - 1);
-                trie->maxlen -= (state - 1);
-#ifdef DEBUGGING
-               /* At least the UNICOS C compiler choked on this
-                * being argument to DEBUG_r(), so let's just have
-                * it right here. */
-               if (
-#ifdef PERL_EXT_RE_BUILD
-                   1
-#else
-                   DEBUG_r_TEST
-#endif
-                   ) {
-                   regnode *fix = convert;
-                   U32 word = trie->wordcount;
-                   mjd_nodelen++;
-                   Set_Node_Offset_Length(convert, mjd_offset, state - 1);
-                   while( ++fix < n ) {
-                       Set_Node_Offset_Length(fix, 0, 0);
-                   }
-                   while (word--) {
-                       SV ** const tmp = av_fetch( trie_words, word, 0 );
-                       if (tmp) {
-                           if ( STR_LEN(convert) <= SvCUR(*tmp) )
-                               sv_chop(*tmp, SvPV_nolen(*tmp) + STR_LEN(convert));
-                           else
-                               sv_chop(*tmp, SvPV_nolen(*tmp) + SvCUR(*tmp));
-                       }
-                   }
-               }
-#endif
-                if (trie->maxlen) {
-                    convert = n;
-               } else {
-                    NEXT_OFF(convert) = (U16)(tail - convert);
-                    DEBUG_r(optimize= n);
-                }
-            }
-        }
-        if (!jumper) 
-            jumper = last; 
-        if ( trie->maxlen ) {
-           NEXT_OFF( convert ) = (U16)(tail - convert);
-           ARG_SET( convert, data_slot );
-           /* Store the offset to the first unabsorbed branch in 
-              jump[0], which is otherwise unused by the jump logic. 
-              We use this when dumping a trie and during optimisation. */
-           if (trie->jump) 
-               trie->jump[0] = (U16)(nextbranch - convert);
-            
-            /* If the start state is not accepting (meaning there is no empty string/NOTHING)
-            *   and there is a bitmap
-            *   and the first "jump target" node we found leaves enough room
-            * then convert the TRIE node into a TRIEC node, with the bitmap
-            * embedded inline in the opcode - this is hypothetically faster.
-            */
-            if ( !trie->states[trie->startstate].wordnum
-                && trie->bitmap
-                && ( (char *)jumper - (char *)convert) >= (int)sizeof(struct regnode_charclass) )
-            {
-                OP( convert ) = TRIEC;
-                Copy(trie->bitmap, ((struct regnode_charclass *)convert)->bitmap, ANYOF_BITMAP_SIZE, char);
-                PerlMemShared_free(trie->bitmap);
-                trie->bitmap= NULL;
-            } else 
-                OP( convert ) = TRIE;
-
-            /* store the type in the flags */
-            convert->flags = nodetype;
-            DEBUG_r({
-            optimize = convert 
-                      + NODE_STEP_REGNODE 
-                      + regarglen[ OP( convert ) ];
-            });
-            /* XXX We really should free up the resource in trie now, 
-                   as we won't use them - (which resources?) dmq */
-        }
-        /* needed for dumping*/
-        DEBUG_r(if (optimize) {
-            regnode *opt = convert;
-
-            while ( ++opt < optimize) {
-                Set_Node_Offset_Length(opt,0,0);
-            }
-            /* 
-                Try to clean up some of the debris left after the 
-                optimisation.
-             */
-            while( optimize < jumper ) {
-                mjd_nodelen += Node_Length((optimize));
-                OP( optimize ) = OPTIMIZED;
-                Set_Node_Offset_Length(optimize,0,0);
-                optimize++;
-            }
-            Set_Node_Offset_Length(convert,mjd_offset,mjd_nodelen);
-        });
-    } /* end node insert */
-    REH_CALL_COMP_NODE_HOOK(pRExC_state->rx, convert);
-
-    /*  Finish populating the prev field of the wordinfo array.  Walk back
-     *  from each accept state until we find another accept state, and if
-     *  so, point the first word's .prev field at the second word. If the
-     *  second already has a .prev field set, stop now. This will be the
-     *  case either if we've already processed that word's accept state,
-     *  or that state had multiple words, and the overspill words were
-     *  already linked up earlier.
-     */
-    {
-       U16 word;
-       U32 state;
-       U16 prev;
-
-       for (word=1; word <= trie->wordcount; word++) {
-           prev = 0;
-           if (trie->wordinfo[word].prev)
-               continue;
-           state = trie->wordinfo[word].accept;
-           while (state) {
-               state = prev_states[state];
-               if (!state)
-                   break;
-               prev = trie->states[state].wordnum;
-               if (prev)
-                   break;
-           }
-           trie->wordinfo[word].prev = prev;
-       }
-       Safefree(prev_states);
-    }
-
-
-    /* and now dump out the compressed format */
-    DEBUG_TRIE_COMPILE_r(dump_trie(trie, widecharmap, revcharmap, depth+1));
-
-    RExC_rxi->data->data[ data_slot + 1 ] = (void*)widecharmap;
-#ifdef DEBUGGING
-    RExC_rxi->data->data[ data_slot + TRIE_WORDS_OFFSET ] = (void*)trie_words;
-    RExC_rxi->data->data[ data_slot + 3 ] = (void*)revcharmap;
-#else
-    SvREFCNT_dec(revcharmap);
-#endif
-    return trie->jump 
-           ? MADE_JUMP_TRIE 
-           : trie->startstate>1 
-             ? MADE_EXACT_TRIE 
-             : MADE_TRIE;
-}
-
-STATIC void
-S_make_trie_failtable(pTHX_ RExC_state_t *pRExC_state, regnode *source,  regnode *stclass, U32 depth)
-{
-/* The Trie is constructed and compressed now so we can build a fail array if it's needed
-
-   This is basically the Aho-Corasick algorithm. Its from exercise 3.31 and 3.32 in the
-   "Red Dragon" -- Compilers, principles, techniques, and tools. Aho, Sethi, Ullman 1985/88
-   ISBN 0-201-10088-6
-
-   We find the fail state for each state in the trie, this state is the longest proper
-   suffix of the current state's 'word' that is also a proper prefix of another word in our
-   trie. State 1 represents the word '' and is thus the default fail state. This allows
-   the DFA not to have to restart after its tried and failed a word at a given point, it
-   simply continues as though it had been matching the other word in the first place.
-   Consider
-      'abcdgu'=~/abcdefg|cdgu/
-   When we get to 'd' we are still matching the first word, we would encounter 'g' which would
-   fail, which would bring us to the state representing 'd' in the second word where we would
-   try 'g' and succeed, proceeding to match 'cdgu'.
- */
- /* add a fail transition */
-    const U32 trie_offset = ARG(source);
-    reg_trie_data *trie=(reg_trie_data *)RExC_rxi->data->data[trie_offset];
-    U32 *q;
-    const U32 ucharcount = trie->uniquecharcount;
-    const U32 numstates = trie->statecount;
-    const U32 ubound = trie->lasttrans + ucharcount;
-    U32 q_read = 0;
-    U32 q_write = 0;
-    U32 charid;
-    U32 base = trie->states[ 1 ].trans.base;
-    U32 *fail;
-    reg_ac_data *aho;
-    const U32 data_slot = add_data( pRExC_state, 1, "T" );
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_MAKE_TRIE_FAILTABLE;
-#ifndef DEBUGGING
-    PERL_UNUSED_ARG(depth);
-#endif
-
-
-    ARG_SET( stclass, data_slot );
-    aho = (reg_ac_data *) PerlMemShared_calloc( 1, sizeof(reg_ac_data) );
-    RExC_rxi->data->data[ data_slot ] = (void*)aho;
-    aho->trie=trie_offset;
-    aho->states=(reg_trie_state *)PerlMemShared_malloc( numstates * sizeof(reg_trie_state) );
-    Copy( trie->states, aho->states, numstates, reg_trie_state );
-    Newxz( q, numstates, U32);
-    aho->fail = (U32 *) PerlMemShared_calloc( numstates, sizeof(U32) );
-    aho->refcount = 1;
-    fail = aho->fail;
-    /* initialize fail[0..1] to be 1 so that we always have
-       a valid final fail state */
-    fail[ 0 ] = fail[ 1 ] = 1;
-
-    for ( charid = 0; charid < ucharcount ; charid++ ) {
-       const U32 newstate = TRIE_TRANS_STATE( 1, base, ucharcount, charid, 0 );
-       if ( newstate ) {
-            q[ q_write ] = newstate;
-            /* set to point at the root */
-            fail[ q[ q_write++ ] ]=1;
-        }
-    }
-    while ( q_read < q_write) {
-       const U32 cur = q[ q_read++ % numstates ];
-        base = trie->states[ cur ].trans.base;
-
-        for ( charid = 0 ; charid < ucharcount ; charid++ ) {
-           const U32 ch_state = TRIE_TRANS_STATE( cur, base, ucharcount, charid, 1 );
-           if (ch_state) {
-                U32 fail_state = cur;
-                U32 fail_base;
-                do {
-                    fail_state = fail[ fail_state ];
-                    fail_base = aho->states[ fail_state ].trans.base;
-                } while ( !TRIE_TRANS_STATE( fail_state, fail_base, ucharcount, charid, 1 ) );
-
-                fail_state = TRIE_TRANS_STATE( fail_state, fail_base, ucharcount, charid, 1 );
-                fail[ ch_state ] = fail_state;
-                if ( !aho->states[ ch_state ].wordnum && aho->states[ fail_state ].wordnum )
-                {
-                        aho->states[ ch_state ].wordnum =  aho->states[ fail_state ].wordnum;
-                }
-                q[ q_write++ % numstates] = ch_state;
-            }
-        }
-    }
-    /* restore fail[0..1] to 0 so that we "fall out" of the AC loop
-       when we fail in state 1, this allows us to use the
-       charclass scan to find a valid start char. This is based on the principle
-       that theres a good chance the string being searched contains lots of stuff
-       that cant be a start char.
-     */
-    fail[ 0 ] = fail[ 1 ] = 0;
-    DEBUG_TRIE_COMPILE_r({
-        PerlIO_printf(Perl_debug_log,
-                     "%*sStclass Failtable (%"UVuf" states): 0", 
-                     (int)(depth * 2), "", (UV)numstates
-        );
-        for( q_read=1; q_read<numstates; q_read++ ) {
-            PerlIO_printf(Perl_debug_log, ", %"UVuf, (UV)fail[q_read]);
-        }
-        PerlIO_printf(Perl_debug_log, "\n");
-    });
-    Safefree(q);
-    /*RExC_seen |= REG_SEEN_TRIEDFA;*/
-}
-
-
-/*
- * There are strange code-generation bugs caused on sparc64 by gcc-2.95.2.
- * These need to be revisited when a newer toolchain becomes available.
- */
-#if defined(__sparc64__) && defined(__GNUC__)
-#   if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 96)
-#       undef  SPARC64_GCC_WORKAROUND
-#       define SPARC64_GCC_WORKAROUND 1
-#   endif
-#endif
-
-#define DEBUG_PEEP(str,scan,depth) \
-    DEBUG_OPTIMISE_r({if (scan){ \
-       SV * const mysv=sv_newmortal(); \
-       regnode *Next = regnext(scan); \
-       regprop(RExC_rx, mysv, scan); \
-       PerlIO_printf(Perl_debug_log, "%*s" str ">%3d: %s (%d)\n", \
-       (int)depth*2, "", REG_NODE_NUM(scan), SvPV_nolen_const(mysv),\
-       Next ? (REG_NODE_NUM(Next)) : 0 ); \
-   }});
-
-
-
-
-
-#define JOIN_EXACT(scan,min,flags) \
-    if (PL_regkind[OP(scan)] == EXACT) \
-        join_exact(pRExC_state,(scan),(min),(flags),NULL,depth+1)
-
-STATIC U32
-S_join_exact(pTHX_ RExC_state_t *pRExC_state, regnode *scan, I32 *min, U32 flags,regnode *val, U32 depth) {
-    /* Merge several consecutive EXACTish nodes into one. */
-    regnode *n = regnext(scan);
-    U32 stringok = 1;
-    regnode *next = scan + NODE_SZ_STR(scan);
-    U32 merged = 0;
-    U32 stopnow = 0;
-#ifdef DEBUGGING
-    regnode *stop = scan;
-    GET_RE_DEBUG_FLAGS_DECL;
-#else
-    PERL_UNUSED_ARG(depth);
-#endif
-
-    PERL_ARGS_ASSERT_JOIN_EXACT;
-#ifndef EXPERIMENTAL_INPLACESCAN
-    PERL_UNUSED_ARG(flags);
-    PERL_UNUSED_ARG(val);
-#endif
-    DEBUG_PEEP("join",scan,depth);
-    
-    /* Skip NOTHING, merge EXACT*. */
-    while (n &&
-           ( PL_regkind[OP(n)] == NOTHING ||
-             (stringok && (OP(n) == OP(scan))))
-           && NEXT_OFF(n)
-           && NEXT_OFF(scan) + NEXT_OFF(n) < I16_MAX) {
-        
-        if (OP(n) == TAIL || n > next)
-            stringok = 0;
-        if (PL_regkind[OP(n)] == NOTHING) {
-            DEBUG_PEEP("skip:",n,depth);
-            NEXT_OFF(scan) += NEXT_OFF(n);
-            next = n + NODE_STEP_REGNODE;
-#ifdef DEBUGGING
-            if (stringok)
-                stop = n;
-#endif
-            n = regnext(n);
-        }
-        else if (stringok) {
-            const unsigned int oldl = STR_LEN(scan);
-            regnode * const nnext = regnext(n);
-            
-            DEBUG_PEEP("merg",n,depth);
-            
-            merged++;
-            if (oldl + STR_LEN(n) > U8_MAX)
-                break;
-            NEXT_OFF(scan) += NEXT_OFF(n);
-            STR_LEN(scan) += STR_LEN(n);
-            next = n + NODE_SZ_STR(n);
-            /* Now we can overwrite *n : */
-            Move(STRING(n), STRING(scan) + oldl, STR_LEN(n), char);
-#ifdef DEBUGGING
-            stop = next - 1;
-#endif
-            n = nnext;
-            if (stopnow) break;
-        }
-
-#ifdef EXPERIMENTAL_INPLACESCAN
-       if (flags && !NEXT_OFF(n)) {
-           DEBUG_PEEP("atch", val, depth);
-           if (reg_off_by_arg[OP(n)]) {
-               ARG_SET(n, val - n);
-           }
-           else {
-               NEXT_OFF(n) = val - n;
-           }
-           stopnow = 1;
-       }
-#endif
-    }
-#define GREEK_SMALL_LETTER_IOTA_WITH_DIALYTIKA_AND_TONOS   0x0390
-#define IOTA_D_T       GREEK_SMALL_LETTER_IOTA_WITH_DIALYTIKA_AND_TONOS
-#define GREEK_SMALL_LETTER_UPSILON_WITH_DIALYTIKA_AND_TONOS    0x03B0
-#define UPSILON_D_T    GREEK_SMALL_LETTER_UPSILON_WITH_DIALYTIKA_AND_TONOS
-
-    if (UTF
-       && ( OP(scan) == EXACTF || OP(scan) == EXACTFU)
-       && ( STR_LEN(scan) >= 6 ) )
-    {
-    /*
-    Two problematic code points in Unicode casefolding of EXACT nodes:
-    
-    U+0390 - GREEK SMALL LETTER IOTA WITH DIALYTIKA AND TONOS
-    U+03B0 - GREEK SMALL LETTER UPSILON WITH DIALYTIKA AND TONOS
-    
-    which casefold to
-    
-    Unicode                      UTF-8
-    
-    U+03B9 U+0308 U+0301         0xCE 0xB9 0xCC 0x88 0xCC 0x81
-    U+03C5 U+0308 U+0301         0xCF 0x85 0xCC 0x88 0xCC 0x81
-    
-    This means that in case-insensitive matching (or "loose matching",
-    as Unicode calls it), an EXACTF of length six (the UTF-8 encoded byte
-    length of the above casefolded versions) can match a target string
-    of length two (the byte length of UTF-8 encoded U+0390 or U+03B0).
-    This would rather mess up the minimum length computation.
-    
-    What we'll do is to look for the tail four bytes, and then peek
-    at the preceding two bytes to see whether we need to decrease
-    the minimum length by four (six minus two).
-    
-    Thanks to the design of UTF-8, there cannot be false matches:
-    A sequence of valid UTF-8 bytes cannot be a subsequence of
-    another valid sequence of UTF-8 bytes.
-    
-    */
-         char * const s0 = STRING(scan), *s, *t;
-         char * const s1 = s0 + STR_LEN(scan) - 1;
-         char * const s2 = s1 - 4;
-#ifdef EBCDIC /* RD tunifold greek 0390 and 03B0 */
-        const char t0[] = "\xaf\x49\xaf\x42";
-#else
-         const char t0[] = "\xcc\x88\xcc\x81";
-#endif
-         const char * const t1 = t0 + 3;
-    
-         for (s = s0 + 2;
-              s < s2 && (t = ninstr(s, s1, t0, t1));
-              s = t + 4) {
-#ifdef EBCDIC
-             if (((U8)t[-1] == 0x68 && (U8)t[-2] == 0xB4) ||
-                 ((U8)t[-1] == 0x46 && (U8)t[-2] == 0xB5))
-#else
-              if (((U8)t[-1] == 0xB9 && (U8)t[-2] == 0xCE) ||
-                  ((U8)t[-1] == 0x85 && (U8)t[-2] == 0xCF))
-#endif
-                   *min -= 4;
-         }
-    }
-    
-#ifdef DEBUGGING
-    /* Allow dumping */
-    n = scan + NODE_SZ_STR(scan);
-    while (n <= stop) {
-        if (PL_regkind[OP(n)] != NOTHING || OP(n) == NOTHING) {
-            OP(n) = OPTIMIZED;
-            NEXT_OFF(n) = 0;
-        }
-        n++;
-    }
-#endif
-    DEBUG_OPTIMISE_r(if (merged){DEBUG_PEEP("finl",scan,depth)});
-    return stopnow;
-}
-
-/* REx optimizer.  Converts nodes into quicker variants "in place".
-   Finds fixed substrings.  */
-
-/* Stops at toplevel WHILEM as well as at "last". At end *scanp is set
-   to the position after last scanned or to NULL. */
-
-#define INIT_AND_WITHP \
-    assert(!and_withp); \
-    Newx(and_withp,1,struct regnode_charclass_class); \
-    SAVEFREEPV(and_withp)
-
-/* this is a chain of data about sub patterns we are processing that
-   need to be handled separately/specially in study_chunk. Its so
-   we can simulate recursion without losing state.  */
-struct scan_frame;
-typedef struct scan_frame {
-    regnode *last;  /* last node to process in this frame */
-    regnode *next;  /* next node to process when last is reached */
-    struct scan_frame *prev; /*previous frame*/
-    I32 stop; /* what stopparen do we use */
-} scan_frame;
-
-
-#define SCAN_COMMIT(s, data, m) scan_commit(s, data, m, is_inf)
-
-#define CASE_SYNST_FNC(nAmE)                                       \
-case nAmE:                                                         \
-    if (flags & SCF_DO_STCLASS_AND) {                              \
-           for (value = 0; value < 256; value++)                  \
-               if (!is_ ## nAmE ## _cp(value))                       \
-                   ANYOF_BITMAP_CLEAR(data->start_class, value);  \
-    }                                                              \
-    else {                                                         \
-           for (value = 0; value < 256; value++)                  \
-               if (is_ ## nAmE ## _cp(value))                        \
-                   ANYOF_BITMAP_SET(data->start_class, value);    \
-    }                                                              \
-    break;                                                         \
-case N ## nAmE:                                                    \
-    if (flags & SCF_DO_STCLASS_AND) {                              \
-           for (value = 0; value < 256; value++)                   \
-               if (is_ ## nAmE ## _cp(value))                         \
-                   ANYOF_BITMAP_CLEAR(data->start_class, value);   \
-    }                                                               \
-    else {                                                          \
-           for (value = 0; value < 256; value++)                   \
-               if (!is_ ## nAmE ## _cp(value))                        \
-                   ANYOF_BITMAP_SET(data->start_class, value);     \
-    }                                                               \
-    break
-
-
-
-STATIC I32
-S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp,
-                        I32 *minlenp, I32 *deltap,
-                       regnode *last,
-                       scan_data_t *data,
-                       I32 stopparen,
-                       U8* recursed,
-                       struct regnode_charclass_class *and_withp,
-                       U32 flags, U32 depth)
-                       /* scanp: Start here (read-write). */
-                       /* deltap: Write maxlen-minlen here. */
-                       /* last: Stop before this one. */
-                       /* data: string data about the pattern */
-                       /* stopparen: treat close N as END */
-                       /* recursed: which subroutines have we recursed into */
-                       /* and_withp: Valid if flags & SCF_DO_STCLASS_OR */
-{
-    dVAR;
-    I32 min = 0, pars = 0, code;
-    regnode *scan = *scanp, *next;
-    I32 delta = 0;
-    int is_inf = (flags & SCF_DO_SUBSTR) && (data->flags & SF_IS_INF);
-    int is_inf_internal = 0;           /* The studied chunk is infinite */
-    I32 is_par = OP(scan) == OPEN ? ARG(scan) : 0;
-    scan_data_t data_fake;
-    SV *re_trie_maxbuff = NULL;
-    regnode *first_non_open = scan;
-    I32 stopmin = I32_MAX;
-    scan_frame *frame = NULL;
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_STUDY_CHUNK;
-
-#ifdef DEBUGGING
-    StructCopy(&zero_scan_data, &data_fake, scan_data_t);
-#endif
-
-    if ( depth == 0 ) {
-        while (first_non_open && OP(first_non_open) == OPEN)
-            first_non_open=regnext(first_non_open);
-    }
-
-
-  fake_study_recurse:
-    while ( scan && OP(scan) != END && scan < last ){
-       /* Peephole optimizer: */
-       DEBUG_STUDYDATA("Peep:", data,depth);
-       DEBUG_PEEP("Peep",scan,depth);
-        JOIN_EXACT(scan,&min,0);
-
-       /* Follow the next-chain of the current node and optimize
-          away all the NOTHINGs from it.  */
-       if (OP(scan) != CURLYX) {
-           const int max = (reg_off_by_arg[OP(scan)]
-                      ? I32_MAX
-                      /* I32 may be smaller than U16 on CRAYs! */
-                      : (I32_MAX < U16_MAX ? I32_MAX : U16_MAX));
-           int off = (reg_off_by_arg[OP(scan)] ? ARG(scan) : NEXT_OFF(scan));
-           int noff;
-           regnode *n = scan;
-       
-           /* Skip NOTHING and LONGJMP. */
-           while ((n = regnext(n))
-                  && ((PL_regkind[OP(n)] == NOTHING && (noff = NEXT_OFF(n)))
-                      || ((OP(n) == LONGJMP) && (noff = ARG(n))))
-                  && off + noff < max)
-               off += noff;
-           if (reg_off_by_arg[OP(scan)])
-               ARG(scan) = off;
-           else
-               NEXT_OFF(scan) = off;
-       }
-
-
-
-       /* The principal pseudo-switch.  Cannot be a switch, since we
-          look into several different things.  */
-       if (OP(scan) == BRANCH || OP(scan) == BRANCHJ
-                  || OP(scan) == IFTHEN) {
-           next = regnext(scan);
-           code = OP(scan);
-           /* demq: the op(next)==code check is to see if we have "branch-branch" AFAICT */
-       
-           if (OP(next) == code || code == IFTHEN) {
-               /* NOTE - There is similar code to this block below for handling
-                  TRIE nodes on a re-study.  If you change stuff here check there
-                  too. */
-               I32 max1 = 0, min1 = I32_MAX, num = 0;
-               struct regnode_charclass_class accum;
-               regnode * const startbranch=scan;
-               
-               if (flags & SCF_DO_SUBSTR)
-                   SCAN_COMMIT(pRExC_state, data, minlenp); /* Cannot merge strings after this. */
-               if (flags & SCF_DO_STCLASS)
-                   cl_init_zero(pRExC_state, &accum);
-
-               while (OP(scan) == code) {
-                   I32 deltanext, minnext, f = 0, fake;
-                   struct regnode_charclass_class this_class;
-
-                   num++;
-                   data_fake.flags = 0;
-                   if (data) {
-                       data_fake.whilem_c = data->whilem_c;
-                       data_fake.last_closep = data->last_closep;
-                   }
-                   else
-                       data_fake.last_closep = &fake;
-
-                   data_fake.pos_delta = delta;
-                   next = regnext(scan);
-                   scan = NEXTOPER(scan);
-                   if (code != BRANCH)
-                       scan = NEXTOPER(scan);
-                   if (flags & SCF_DO_STCLASS) {
-                       cl_init(pRExC_state, &this_class);
-                       data_fake.start_class = &this_class;
-                       f = SCF_DO_STCLASS_AND;
-                   }
-                   if (flags & SCF_WHILEM_VISITED_POS)
-                       f |= SCF_WHILEM_VISITED_POS;
-
-                   /* we suppose the run is continuous, last=next...*/
-                   minnext = study_chunk(pRExC_state, &scan, minlenp, &deltanext,
-                                         next, &data_fake,
-                                         stopparen, recursed, NULL, f,depth+1);
-                   if (min1 > minnext)
-                       min1 = minnext;
-                   if (max1 < minnext + deltanext)
-                       max1 = minnext + deltanext;
-                   if (deltanext == I32_MAX)
-                       is_inf = is_inf_internal = 1;
-                   scan = next;
-                   if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
-                       pars++;
-                   if (data_fake.flags & SCF_SEEN_ACCEPT) {
-                       if ( stopmin > minnext) 
-                           stopmin = min + min1;
-                       flags &= ~SCF_DO_SUBSTR;
-                       if (data)
-                           data->flags |= SCF_SEEN_ACCEPT;
-                   }
-                   if (data) {
-                       if (data_fake.flags & SF_HAS_EVAL)
-                           data->flags |= SF_HAS_EVAL;
-                       data->whilem_c = data_fake.whilem_c;
-                   }
-                   if (flags & SCF_DO_STCLASS)
-                       cl_or(pRExC_state, &accum, &this_class);
-               }
-               if (code == IFTHEN && num < 2) /* Empty ELSE branch */
-                   min1 = 0;
-               if (flags & SCF_DO_SUBSTR) {
-                   data->pos_min += min1;
-                   data->pos_delta += max1 - min1;
-                   if (max1 != min1 || is_inf)
-                       data->longest = &(data->longest_float);
-               }
-               min += min1;
-               delta += max1 - min1;
-               if (flags & SCF_DO_STCLASS_OR) {
-                   cl_or(pRExC_state, data->start_class, &accum);
-                   if (min1) {
-                       cl_and(data->start_class, and_withp);
-                       flags &= ~SCF_DO_STCLASS;
-                   }
-               }
-               else if (flags & SCF_DO_STCLASS_AND) {
-                   if (min1) {
-                       cl_and(data->start_class, &accum);
-                       flags &= ~SCF_DO_STCLASS;
-                   }
-                   else {
-                       /* Switch to OR mode: cache the old value of
-                        * data->start_class */
-                       INIT_AND_WITHP;
-                       StructCopy(data->start_class, and_withp,
-                                  struct regnode_charclass_class);
-                       flags &= ~SCF_DO_STCLASS_AND;
-                       StructCopy(&accum, data->start_class,
-                                  struct regnode_charclass_class);
-                       flags |= SCF_DO_STCLASS_OR;
-                       data->start_class->flags |= ANYOF_EOS;
-                   }
-               }
-
-                if (PERL_ENABLE_TRIE_OPTIMISATION && OP( startbranch ) == BRANCH ) {
-               /* demq.
-
-                  Assuming this was/is a branch we are dealing with: 'scan' now
-                  points at the item that follows the branch sequence, whatever
-                  it is. We now start at the beginning of the sequence and look
-                  for subsequences of
-
-                  BRANCH->EXACT=>x1
-                  BRANCH->EXACT=>x2
-                  tail
-
-                  which would be constructed from a pattern like /A|LIST|OF|WORDS/
-
-                  If we can find such a subsequence we need to turn the first
-                  element into a trie and then add the subsequent branch exact
-                  strings to the trie.
-
-                  We have two cases
-
-                    1. patterns where the whole set of branches can be converted. 
-
-                    2. patterns where only a subset can be converted.
-
-                  In case 1 we can replace the whole set with a single regop
-                  for the trie. In case 2 we need to keep the start and end
-                  branches so
-
-                    'BRANCH EXACT; BRANCH EXACT; BRANCH X'
-                    becomes BRANCH TRIE; BRANCH X;
-
-                 There is an additional case, that being where there is a 
-                 common prefix, which gets split out into an EXACT like node
-                 preceding the TRIE node.
-
-                 If x(1..n)==tail then we can do a simple trie, if not we make
-                 a "jump" trie, such that when we match the appropriate word
-                 we "jump" to the appropriate tail node. Essentially we turn
-                 a nested if into a case structure of sorts.
-
-               */
-               
-                   int made=0;
-                   if (!re_trie_maxbuff) {
-                       re_trie_maxbuff = get_sv(RE_TRIE_MAXBUF_NAME, 1);
-                       if (!SvIOK(re_trie_maxbuff))
-                           sv_setiv(re_trie_maxbuff, RE_TRIE_MAXBUF_INIT);
-                   }
-                    if ( SvIV(re_trie_maxbuff)>=0  ) {
-                        regnode *cur;
-                        regnode *first = (regnode *)NULL;
-                        regnode *last = (regnode *)NULL;
-                        regnode *tail = scan;
-                        U8 optype = 0;
-                        U32 count=0;
-
-#ifdef DEBUGGING
-                        SV * const mysv = sv_newmortal();       /* for dumping */
-#endif
-                        /* var tail is used because there may be a TAIL
-                           regop in the way. Ie, the exacts will point to the
-                           thing following the TAIL, but the last branch will
-                           point at the TAIL. So we advance tail. If we
-                           have nested (?:) we may have to move through several
-                           tails.
-                         */
-
-                        while ( OP( tail ) == TAIL ) {
-                            /* this is the TAIL generated by (?:) */
-                            tail = regnext( tail );
-                        }
-
-                        
-                        DEBUG_OPTIMISE_r({
-                            regprop(RExC_rx, mysv, tail );
-                            PerlIO_printf( Perl_debug_log, "%*s%s%s\n",
-                                (int)depth * 2 + 2, "", 
-                                "Looking for TRIE'able sequences. Tail node is: ", 
-                                SvPV_nolen_const( mysv )
-                            );
-                        });
-                        
-                        /*
-
-                           step through the branches, cur represents each
-                           branch, noper is the first thing to be matched
-                           as part of that branch and noper_next is the
-                           regnext() of that node. if noper is an EXACT
-                           and noper_next is the same as scan (our current
-                           position in the regex) then the EXACT branch is
-                           a possible optimization target. Once we have
-                           two or more consecutive such branches we can
-                           create a trie of the EXACT's contents and stich
-                           it in place. If the sequence represents all of
-                           the branches we eliminate the whole thing and
-                           replace it with a single TRIE. If it is a
-                           subsequence then we need to stitch it in. This
-                           means the first branch has to remain, and needs
-                           to be repointed at the item on the branch chain
-                           following the last branch optimized. This could
-                           be either a BRANCH, in which case the
-                           subsequence is internal, or it could be the
-                           item following the branch sequence in which
-                           case the subsequence is at the end.
-
-                        */
-
-                        /* dont use tail as the end marker for this traverse */
-                        for ( cur = startbranch ; cur != scan ; cur = regnext( cur ) ) {
-                            regnode * const noper = NEXTOPER( cur );
-#if defined(DEBUGGING) || defined(NOJUMPTRIE)
-                            regnode * const noper_next = regnext( noper );
-#endif
-
-                            DEBUG_OPTIMISE_r({
-                                regprop(RExC_rx, mysv, cur);
-                                PerlIO_printf( Perl_debug_log, "%*s- %s (%d)",
-                                   (int)depth * 2 + 2,"", SvPV_nolen_const( mysv ), REG_NODE_NUM(cur) );
-
-                                regprop(RExC_rx, mysv, noper);
-                                PerlIO_printf( Perl_debug_log, " -> %s",
-                                    SvPV_nolen_const(mysv));
-
-                                if ( noper_next ) {
-                                  regprop(RExC_rx, mysv, noper_next );
-                                  PerlIO_printf( Perl_debug_log,"\t=> %s\t",
-                                    SvPV_nolen_const(mysv));
-                                }
-                                PerlIO_printf( Perl_debug_log, "(First==%d,Last==%d,Cur==%d)\n",
-                                   REG_NODE_NUM(first), REG_NODE_NUM(last), REG_NODE_NUM(cur) );
-                            });
-                            if ( (((first && optype!=NOTHING) ? OP( noper ) == optype
-                                         : PL_regkind[ OP( noper ) ] == EXACT )
-                                  || OP(noper) == NOTHING )
-#ifdef NOJUMPTRIE
-                                  && noper_next == tail
-#endif
-                                  && count < U16_MAX)
-                            {
-                                count++;
-                                if ( !first || optype == NOTHING ) {
-                                    if (!first) first = cur;
-                                    optype = OP( noper );
-                                } else {
-                                    last = cur;
-                                }
-                            } else {
-/* 
-    Currently we do not believe that the trie logic can
-    handle case insensitive matching properly when the
-    pattern is not unicode (thus forcing unicode semantics).
-
-    If/when this is fixed the following define can be swapped
-    in below to fully enable trie logic.
-
-#define TRIE_TYPE_IS_SAFE 1
-
-*/
-#define TRIE_TYPE_IS_SAFE (UTF || optype==EXACT)
-
-                                if ( last && TRIE_TYPE_IS_SAFE ) {
-                                    make_trie( pRExC_state, 
-                                            startbranch, first, cur, tail, count, 
-                                            optype, depth+1 );
-                                }
-                                if ( PL_regkind[ OP( noper ) ] == EXACT
-#ifdef NOJUMPTRIE
-                                     && noper_next == tail
-#endif
-                                ){
-                                    count = 1;
-                                    first = cur;
-                                    optype = OP( noper );
-                                } else {
-                                    count = 0;
-                                    first = NULL;
-                                    optype = 0;
-                                }
-                                last = NULL;
-                            }
-                        }
-                        DEBUG_OPTIMISE_r({
-                            regprop(RExC_rx, mysv, cur);
-                            PerlIO_printf( Perl_debug_log,
-                              "%*s- %s (%d) <SCAN FINISHED>\n", (int)depth * 2 + 2,
-                              "", SvPV_nolen_const( mysv ),REG_NODE_NUM(cur));
-
-                        });
-                        
-                        if ( last && TRIE_TYPE_IS_SAFE ) {
-                            made= make_trie( pRExC_state, startbranch, first, scan, tail, count, optype, depth+1 );
-#ifdef TRIE_STUDY_OPT  
-                            if ( ((made == MADE_EXACT_TRIE && 
-                                 startbranch == first) 
-                                 || ( first_non_open == first )) && 
-                                 depth==0 ) {
-                                flags |= SCF_TRIE_RESTUDY;
-                                if ( startbranch == first 
-                                     && scan == tail ) 
-                                {
-                                    RExC_seen &=~REG_TOP_LEVEL_BRANCHES;
-                                }
-                            }
-#endif
-                        }
-                    }
-                    
-                } /* do trie */
-                
-           }
-           else if ( code == BRANCHJ ) {  /* single branch is optimized. */
-               scan = NEXTOPER(NEXTOPER(scan));
-           } else                      /* single branch is optimized. */
-               scan = NEXTOPER(scan);
-           continue;
-       } else if (OP(scan) == SUSPEND || OP(scan) == GOSUB || OP(scan) == GOSTART) {
-           scan_frame *newframe = NULL;
-           I32 paren;
-           regnode *start;
-           regnode *end;
-
-           if (OP(scan) != SUSPEND) {
-           /* set the pointer */
-               if (OP(scan) == GOSUB) {
-                   paren = ARG(scan);
-                   RExC_recurse[ARG2L(scan)] = scan;
-                    start = RExC_open_parens[paren-1];
-                    end   = RExC_close_parens[paren-1];
-                } else {
-                    paren = 0;
-                    start = RExC_rxi->program + 1;
-                    end   = RExC_opend;
-                }
-                if (!recursed) {
-                    Newxz(recursed, (((RExC_npar)>>3) +1), U8);
-                    SAVEFREEPV(recursed);
-                }
-                if (!PAREN_TEST(recursed,paren+1)) {
-                   PAREN_SET(recursed,paren+1);
-                    Newx(newframe,1,scan_frame);
-                } else {
-                    if (flags & SCF_DO_SUBSTR) {
-                        SCAN_COMMIT(pRExC_state,data,minlenp);
-                        data->longest = &(data->longest_float);
-                    }
-                    is_inf = is_inf_internal = 1;
-                    if (flags & SCF_DO_STCLASS_OR) /* Allow everything */
-                        cl_anything(pRExC_state, data->start_class);
-                    flags &= ~SCF_DO_STCLASS;
-               }
-            } else {
-               Newx(newframe,1,scan_frame);
-               paren = stopparen;
-               start = scan+2;
-               end = regnext(scan);
-           }
-           if (newframe) {
-                assert(start);
-                assert(end);
-               SAVEFREEPV(newframe);
-               newframe->next = regnext(scan);
-               newframe->last = last;
-               newframe->stop = stopparen;
-               newframe->prev = frame;
-
-               frame = newframe;
-               scan =  start;
-               stopparen = paren;
-               last = end;
-
-               continue;
-           }
-       }
-       else if (OP(scan) == EXACT) {
-           I32 l = STR_LEN(scan);
-           UV uc;
-           if (UTF) {
-               const U8 * const s = (U8*)STRING(scan);
-               l = utf8_length(s, s + l);
-               uc = utf8_to_uvchr(s, NULL);
-           } else {
-               uc = *((U8*)STRING(scan));
-           }
-           min += l;
-           if (flags & SCF_DO_SUBSTR) { /* Update longest substr. */
-               /* The code below prefers earlier match for fixed
-                  offset, later match for variable offset.  */
-               if (data->last_end == -1) { /* Update the start info. */
-                   data->last_start_min = data->pos_min;
-                   data->last_start_max = is_inf
-                       ? I32_MAX : data->pos_min + data->pos_delta;
-               }
-               sv_catpvn(data->last_found, STRING(scan), STR_LEN(scan));
-               if (UTF)
-                   SvUTF8_on(data->last_found);
-               {
-                   SV * const sv = data->last_found;
-                   MAGIC * const mg = SvUTF8(sv) && SvMAGICAL(sv) ?
-                       mg_find(sv, PERL_MAGIC_utf8) : NULL;
-                   if (mg && mg->mg_len >= 0)
-                       mg->mg_len += utf8_length((U8*)STRING(scan),
-                                                 (U8*)STRING(scan)+STR_LEN(scan));
-               }
-               data->last_end = data->pos_min + l;
-               data->pos_min += l; /* As in the first entry. */
-               data->flags &= ~SF_BEFORE_EOL;
-           }
-           if (flags & SCF_DO_STCLASS_AND) {
-               /* Check whether it is compatible with what we know already! */
-               int compat = 1;
-
-
-               /* If compatible, we or it in below.  It is compatible if is
-                * in the bitmp and either 1) its bit or its fold is set, or 2)
-                * it's for a locale.  Even if there isn't unicode semantics
-                * here, at runtime there may be because of matching against a
-                * utf8 string, so accept a possible false positive for
-                * latin1-range folds */
-               if (uc >= 0x100 ||
-                   (!(data->start_class->flags & (ANYOF_CLASS | ANYOF_LOCALE))
-                   && !ANYOF_BITMAP_TEST(data->start_class, uc)
-                   && (!(data->start_class->flags & ANYOF_LOC_NONBITMAP_FOLD)
-                       || !ANYOF_BITMAP_TEST(data->start_class, PL_fold_latin1[uc])))
-                    )
-                   compat = 0;
-               ANYOF_CLASS_ZERO(data->start_class);
-               ANYOF_BITMAP_ZERO(data->start_class);
-               if (compat)
-                   ANYOF_BITMAP_SET(data->start_class, uc);
-               data->start_class->flags &= ~ANYOF_EOS;
-               if (uc < 0x100)
-                 data->start_class->flags &= ~ANYOF_UNICODE_ALL;
-           }
-           else if (flags & SCF_DO_STCLASS_OR) {
-               /* false positive possible if the class is case-folded */
-               if (uc < 0x100)
-                   ANYOF_BITMAP_SET(data->start_class, uc);
-               else
-                   data->start_class->flags |= ANYOF_UNICODE_ALL;
-               data->start_class->flags &= ~ANYOF_EOS;
-               cl_and(data->start_class, and_withp);
-           }
-           flags &= ~SCF_DO_STCLASS;
-       }
-       else if (PL_regkind[OP(scan)] == EXACT) { /* But OP != EXACT! */
-           I32 l = STR_LEN(scan);
-           UV uc = *((U8*)STRING(scan));
-
-           /* Search for fixed substrings supports EXACT only. */
-           if (flags & SCF_DO_SUBSTR) {
-               assert(data);
-               SCAN_COMMIT(pRExC_state, data, minlenp);
-           }
-           if (UTF) {
-               const U8 * const s = (U8 *)STRING(scan);
-               l = utf8_length(s, s + l);
-               uc = utf8_to_uvchr(s, NULL);
-           }
-           min += l;
-           if (flags & SCF_DO_SUBSTR)
-               data->pos_min += l;
-           if (flags & SCF_DO_STCLASS_AND) {
-               /* Check whether it is compatible with what we know already! */
-               int compat = 1;
-               if (uc >= 0x100 ||
-                (!(data->start_class->flags & (ANYOF_CLASS | ANYOF_LOCALE))
-                 && !ANYOF_BITMAP_TEST(data->start_class, uc)
-                 && !ANYOF_BITMAP_TEST(data->start_class, PL_fold_latin1[uc])))
-               {
-                   compat = 0;
-               }
-               ANYOF_CLASS_ZERO(data->start_class);
-               ANYOF_BITMAP_ZERO(data->start_class);
-               if (compat) {
-                   ANYOF_BITMAP_SET(data->start_class, uc);
-                   data->start_class->flags &= ~ANYOF_EOS;
-                   data->start_class->flags |= ANYOF_LOC_NONBITMAP_FOLD;
-                   if (OP(scan) == EXACTFL) {
-                       data->start_class->flags |= ANYOF_LOCALE;
-                   }
-                   else {
-
-                       /* Also set the other member of the fold pair.  In case
-                        * that unicode semantics is called for at runtime, use
-                        * the full latin1 fold.  (Can't do this for locale,
-                        * because not known until runtime */
-                       ANYOF_BITMAP_SET(data->start_class, PL_fold_latin1[uc]);
-                   }
-               }
-           }
-           else if (flags & SCF_DO_STCLASS_OR) {
-               if (data->start_class->flags & ANYOF_LOC_NONBITMAP_FOLD) {
-                   /* false positive possible if the class is case-folded.
-                      Assume that the locale settings are the same... */
-                   if (uc < 0x100) {
-                       ANYOF_BITMAP_SET(data->start_class, uc);
-                        if (OP(scan) != EXACTFL) {
-
-                            /* And set the other member of the fold pair, but
-                             * can't do that in locale because not known until
-                             * run-time */
-                            ANYOF_BITMAP_SET(data->start_class,
-                                            PL_fold_latin1[uc]);
-                        }
-                   }
-                   data->start_class->flags &= ~ANYOF_EOS;
-               }
-               cl_and(data->start_class, and_withp);
-           }
-           flags &= ~SCF_DO_STCLASS;
-       }
-       else if (REGNODE_VARIES(OP(scan))) {
-           I32 mincount, maxcount, minnext, deltanext, fl = 0;
-           I32 f = flags, pos_before = 0;
-           regnode * const oscan = scan;
-           struct regnode_charclass_class this_class;
-           struct regnode_charclass_class *oclass = NULL;
-           I32 next_is_eval = 0;
-
-           switch (PL_regkind[OP(scan)]) {
-           case WHILEM:                /* End of (?:...)* . */
-               scan = NEXTOPER(scan);
-               goto finish;
-           case PLUS:
-               if (flags & (SCF_DO_SUBSTR | SCF_DO_STCLASS)) {
-                   next = NEXTOPER(scan);
-                   if (OP(next) == EXACT || (flags & SCF_DO_STCLASS)) {
-                       mincount = 1;
-                       maxcount = REG_INFTY;
-                       next = regnext(scan);
-                       scan = NEXTOPER(scan);
-                       goto do_curly;
-                   }
-               }
-               if (flags & SCF_DO_SUBSTR)
-                   data->pos_min++;
-               min++;
-               /* Fall through. */
-           case STAR:
-               if (flags & SCF_DO_STCLASS) {
-                   mincount = 0;
-                   maxcount = REG_INFTY;
-                   next = regnext(scan);
-                   scan = NEXTOPER(scan);
-                   goto do_curly;
-               }
-               is_inf = is_inf_internal = 1;
-               scan = regnext(scan);
-               if (flags & SCF_DO_SUBSTR) {
-                   SCAN_COMMIT(pRExC_state, data, minlenp); /* Cannot extend fixed substrings */
-                   data->longest = &(data->longest_float);
-               }
-               goto optimize_curly_tail;
-           case CURLY:
-               if (stopparen>0 && (OP(scan)==CURLYN || OP(scan)==CURLYM)
-                   && (scan->flags == stopparen))
-               {
-                   mincount = 1;
-                   maxcount = 1;
-               } else {
-                   mincount = ARG1(scan);
-                   maxcount = ARG2(scan);
-               }
-               next = regnext(scan);
-               if (OP(scan) == CURLYX) {
-                   I32 lp = (data ? *(data->last_closep) : 0);
-                   scan->flags = ((lp <= (I32)U8_MAX) ? (U8)lp : U8_MAX);
-               }
-               scan = NEXTOPER(scan) + EXTRA_STEP_2ARGS;
-               next_is_eval = (OP(scan) == EVAL);
-             do_curly:
-               if (flags & SCF_DO_SUBSTR) {
-                   if (mincount == 0) SCAN_COMMIT(pRExC_state,data,minlenp); /* Cannot extend fixed substrings */
-                   pos_before = data->pos_min;
-               }
-               if (data) {
-                   fl = data->flags;
-                   data->flags &= ~(SF_HAS_PAR|SF_IN_PAR|SF_HAS_EVAL);
-                   if (is_inf)
-                       data->flags |= SF_IS_INF;
-               }
-               if (flags & SCF_DO_STCLASS) {
-                   cl_init(pRExC_state, &this_class);
-                   oclass = data->start_class;
-                   data->start_class = &this_class;
-                   f |= SCF_DO_STCLASS_AND;
-                   f &= ~SCF_DO_STCLASS_OR;
-               }
-               /* Exclude from super-linear cache processing any {n,m}
-                  regops for which the combination of input pos and regex
-                  pos is not enough information to determine if a match
-                  will be possible.
-
-                  For example, in the regex /foo(bar\s*){4,8}baz/ with the
-                  regex pos at the \s*, the prospects for a match depend not
-                  only on the input position but also on how many (bar\s*)
-                  repeats into the {4,8} we are. */
-               if ((mincount > 1) || (maxcount > 1 && maxcount != REG_INFTY))
-                   f &= ~SCF_WHILEM_VISITED_POS;
-
-               /* This will finish on WHILEM, setting scan, or on NULL: */
-               minnext = study_chunk(pRExC_state, &scan, minlenp, &deltanext, 
-                                     last, data, stopparen, recursed, NULL,
-                                     (mincount == 0
-                                       ? (f & ~SCF_DO_SUBSTR) : f),depth+1);
-
-               if (flags & SCF_DO_STCLASS)
-                   data->start_class = oclass;
-               if (mincount == 0 || minnext == 0) {
-                   if (flags & SCF_DO_STCLASS_OR) {
-                       cl_or(pRExC_state, data->start_class, &this_class);
-                   }
-                   else if (flags & SCF_DO_STCLASS_AND) {
-                       /* Switch to OR mode: cache the old value of
-                        * data->start_class */
-                       INIT_AND_WITHP;
-                       StructCopy(data->start_class, and_withp,
-                                  struct regnode_charclass_class);
-                       flags &= ~SCF_DO_STCLASS_AND;
-                       StructCopy(&this_class, data->start_class,
-                                  struct regnode_charclass_class);
-                       flags |= SCF_DO_STCLASS_OR;
-                       data->start_class->flags |= ANYOF_EOS;
-                   }
-               } else {                /* Non-zero len */
-                   if (flags & SCF_DO_STCLASS_OR) {
-                       cl_or(pRExC_state, data->start_class, &this_class);
-                       cl_and(data->start_class, and_withp);
-                   }
-                   else if (flags & SCF_DO_STCLASS_AND)
-                       cl_and(data->start_class, &this_class);
-                   flags &= ~SCF_DO_STCLASS;
-               }
-               if (!scan)              /* It was not CURLYX, but CURLY. */
-                   scan = next;
-               if ( /* ? quantifier ok, except for (?{ ... }) */
-                   (next_is_eval || !(mincount == 0 && maxcount == 1))
-                   && (minnext == 0) && (deltanext == 0)
-                   && data && !(data->flags & (SF_HAS_PAR|SF_IN_PAR))
-                   && maxcount <= REG_INFTY/3) /* Complement check for big count */
-               {
-                   ckWARNreg(RExC_parse,
-                             "Quantifier unexpected on zero-length expression");
-               }
-
-               min += minnext * mincount;
-               is_inf_internal |= ((maxcount == REG_INFTY
-                                    && (minnext + deltanext) > 0)
-                                   || deltanext == I32_MAX);
-               is_inf |= is_inf_internal;
-               delta += (minnext + deltanext) * maxcount - minnext * mincount;
-
-               /* Try powerful optimization CURLYX => CURLYN. */
-               if (  OP(oscan) == CURLYX && data
-                     && data->flags & SF_IN_PAR
-                     && !(data->flags & SF_HAS_EVAL)
-                     && !deltanext && minnext == 1 ) {
-                   /* Try to optimize to CURLYN.  */
-                   regnode *nxt = NEXTOPER(oscan) + EXTRA_STEP_2ARGS;
-                   regnode * const nxt1 = nxt;
-#ifdef DEBUGGING
-                   regnode *nxt2;
-#endif
-
-                   /* Skip open. */
-                   nxt = regnext(nxt);
-                   if (!REGNODE_SIMPLE(OP(nxt))
-                       && !(PL_regkind[OP(nxt)] == EXACT
-                            && STR_LEN(nxt) == 1))
-                       goto nogo;
-#ifdef DEBUGGING
-                   nxt2 = nxt;
-#endif
-                   nxt = regnext(nxt);
-                   if (OP(nxt) != CLOSE)
-                       goto nogo;
-                   if (RExC_open_parens) {
-                       RExC_open_parens[ARG(nxt1)-1]=oscan; /*open->CURLYM*/
-                       RExC_close_parens[ARG(nxt1)-1]=nxt+2; /*close->while*/
-                   }
-                   /* Now we know that nxt2 is the only contents: */
-                   oscan->flags = (U8)ARG(nxt);
-                   OP(oscan) = CURLYN;
-                   OP(nxt1) = NOTHING; /* was OPEN. */
-
-#ifdef DEBUGGING
-                   OP(nxt1 + 1) = OPTIMIZED; /* was count. */
-                   NEXT_OFF(nxt1+ 1) = 0; /* just for consistency. */
-                   NEXT_OFF(nxt2) = 0; /* just for consistency with CURLY. */
-                   OP(nxt) = OPTIMIZED;        /* was CLOSE. */
-                   OP(nxt + 1) = OPTIMIZED; /* was count. */
-                   NEXT_OFF(nxt+ 1) = 0; /* just for consistency. */
-#endif
-               }
-             nogo:
-
-               /* Try optimization CURLYX => CURLYM. */
-               if (  OP(oscan) == CURLYX && data
-                     && !(data->flags & SF_HAS_PAR)
-                     && !(data->flags & SF_HAS_EVAL)
-                     && !deltanext     /* atom is fixed width */
-                     && minnext != 0   /* CURLYM can't handle zero width */
-               ) {
-                   /* XXXX How to optimize if data == 0? */
-                   /* Optimize to a simpler form.  */
-                   regnode *nxt = NEXTOPER(oscan) + EXTRA_STEP_2ARGS; /* OPEN */
-                   regnode *nxt2;
-
-                   OP(oscan) = CURLYM;
-                   while ( (nxt2 = regnext(nxt)) /* skip over embedded stuff*/
-                           && (OP(nxt2) != WHILEM))
-                       nxt = nxt2;
-                   OP(nxt2)  = SUCCEED; /* Whas WHILEM */
-                   /* Need to optimize away parenths. */
-                   if ((data->flags & SF_IN_PAR) && OP(nxt) == CLOSE) {
-                       /* Set the parenth number.  */
-                       regnode *nxt1 = NEXTOPER(oscan) + EXTRA_STEP_2ARGS; /* OPEN*/
-
-                       oscan->flags = (U8)ARG(nxt);
-                       if (RExC_open_parens) {
-                           RExC_open_parens[ARG(nxt1)-1]=oscan; /*open->CURLYM*/
-                           RExC_close_parens[ARG(nxt1)-1]=nxt2+1; /*close->NOTHING*/
-                       }
-                       OP(nxt1) = OPTIMIZED;   /* was OPEN. */
-                       OP(nxt) = OPTIMIZED;    /* was CLOSE. */
-
-#ifdef DEBUGGING
-                       OP(nxt1 + 1) = OPTIMIZED; /* was count. */
-                       OP(nxt + 1) = OPTIMIZED; /* was count. */
-                       NEXT_OFF(nxt1 + 1) = 0; /* just for consistency. */
-                       NEXT_OFF(nxt + 1) = 0; /* just for consistency. */
-#endif
-#if 0
-                       while ( nxt1 && (OP(nxt1) != WHILEM)) {
-                           regnode *nnxt = regnext(nxt1);
-                           if (nnxt == nxt) {
-                               if (reg_off_by_arg[OP(nxt1)])
-                                   ARG_SET(nxt1, nxt2 - nxt1);
-                               else if (nxt2 - nxt1 < U16_MAX)
-                                   NEXT_OFF(nxt1) = nxt2 - nxt1;
-                               else
-                                   OP(nxt) = NOTHING;  /* Cannot beautify */
-                           }
-                           nxt1 = nnxt;
-                       }
-#endif
-                       /* Optimize again: */
-                       study_chunk(pRExC_state, &nxt1, minlenp, &deltanext, nxt,
-                                   NULL, stopparen, recursed, NULL, 0,depth+1);
-                   }
-                   else
-                       oscan->flags = 0;
-               }
-               else if ((OP(oscan) == CURLYX)
-                        && (flags & SCF_WHILEM_VISITED_POS)
-                        /* See the comment on a similar expression above.
-                           However, this time it's not a subexpression
-                           we care about, but the expression itself. */
-                        && (maxcount == REG_INFTY)
-                        && data && ++data->whilem_c < 16) {
-                   /* This stays as CURLYX, we can put the count/of pair. */
-                   /* Find WHILEM (as in regexec.c) */
-                   regnode *nxt = oscan + NEXT_OFF(oscan);
-
-                   if (OP(PREVOPER(nxt)) == NOTHING) /* LONGJMP */
-                       nxt += ARG(nxt);
-                   PREVOPER(nxt)->flags = (U8)(data->whilem_c
-                       | (RExC_whilem_seen << 4)); /* On WHILEM */
-               }
-               if (data && fl & (SF_HAS_PAR|SF_IN_PAR))
-                   pars++;
-               if (flags & SCF_DO_SUBSTR) {
-                   SV *last_str = NULL;
-                   int counted = mincount != 0;
-
-                   if (data->last_end > 0 && mincount != 0) { /* Ends with a string. */
-#if defined(SPARC64_GCC_WORKAROUND)
-                       I32 b = 0;
-                       STRLEN l = 0;
-                       const char *s = NULL;
-                       I32 old = 0;
-
-                       if (pos_before >= data->last_start_min)
-                           b = pos_before;
-                       else
-                           b = data->last_start_min;
-
-                       l = 0;
-                       s = SvPV_const(data->last_found, l);
-                       old = b - data->last_start_min;
-
-#else
-                       I32 b = pos_before >= data->last_start_min
-                           ? pos_before : data->last_start_min;
-                       STRLEN l;
-                       const char * const s = SvPV_const(data->last_found, l);
-                       I32 old = b - data->last_start_min;
-#endif
-
-                       if (UTF)
-                           old = utf8_hop((U8*)s, old) - (U8*)s;
-                       l -= old;
-                       /* Get the added string: */
-                       last_str = newSVpvn_utf8(s  + old, l, UTF);
-                       if (deltanext == 0 && pos_before == b) {
-                           /* What was added is a constant string */
-                           if (mincount > 1) {
-                               SvGROW(last_str, (mincount * l) + 1);
-                               repeatcpy(SvPVX(last_str) + l,
-                                         SvPVX_const(last_str), l, mincount - 1);
-                               SvCUR_set(last_str, SvCUR(last_str) * mincount);
-                               /* Add additional parts. */
-                               SvCUR_set(data->last_found,
-                                         SvCUR(data->last_found) - l);
-                               sv_catsv(data->last_found, last_str);
-                               {
-                                   SV * sv = data->last_found;
-                                   MAGIC *mg =
-                                       SvUTF8(sv) && SvMAGICAL(sv) ?
-                                       mg_find(sv, PERL_MAGIC_utf8) : NULL;
-                                   if (mg && mg->mg_len >= 0)
-                                       mg->mg_len += CHR_SVLEN(last_str) - l;
-                               }
-                               data->last_end += l * (mincount - 1);
-                           }
-                       } else {
-                           /* start offset must point into the last copy */
-                           data->last_start_min += minnext * (mincount - 1);
-                           data->last_start_max += is_inf ? I32_MAX
-                               : (maxcount - 1) * (minnext + data->pos_delta);
-                       }
-                   }
-                   /* It is counted once already... */
-                   data->pos_min += minnext * (mincount - counted);
-                   data->pos_delta += - counted * deltanext +
-                       (minnext + deltanext) * maxcount - minnext * mincount;
-                   if (mincount != maxcount) {
-                        /* Cannot extend fixed substrings found inside
-                           the group.  */
-                       SCAN_COMMIT(pRExC_state,data,minlenp);
-                       if (mincount && last_str) {
-                           SV * const sv = data->last_found;
-                           MAGIC * const mg = SvUTF8(sv) && SvMAGICAL(sv) ?
-                               mg_find(sv, PERL_MAGIC_utf8) : NULL;
-
-                           if (mg)
-                               mg->mg_len = -1;
-                           sv_setsv(sv, last_str);
-                           data->last_end = data->pos_min;
-                           data->last_start_min =
-                               data->pos_min - CHR_SVLEN(last_str);
-                           data->last_start_max = is_inf
-                               ? I32_MAX
-                               : data->pos_min + data->pos_delta
-                               - CHR_SVLEN(last_str);
-                       }
-                       data->longest = &(data->longest_float);
-                   }
-                   SvREFCNT_dec(last_str);
-               }
-               if (data && (fl & SF_HAS_EVAL))
-                   data->flags |= SF_HAS_EVAL;
-             optimize_curly_tail:
-               if (OP(oscan) != CURLYX) {
-                   while (PL_regkind[OP(next = regnext(oscan))] == NOTHING
-                          && NEXT_OFF(next))
-                       NEXT_OFF(oscan) += NEXT_OFF(next);
-               }
-               continue;
-           default:                    /* REF, ANYOFV, and CLUMP only? */
-               if (flags & SCF_DO_SUBSTR) {
-                   SCAN_COMMIT(pRExC_state,data,minlenp);      /* Cannot expect anything... */
-                   data->longest = &(data->longest_float);
-               }
-               is_inf = is_inf_internal = 1;
-               if (flags & SCF_DO_STCLASS_OR)
-                   cl_anything(pRExC_state, data->start_class);
-               flags &= ~SCF_DO_STCLASS;
-               break;
-           }
-       }
-       else if (OP(scan) == LNBREAK) {
-           if (flags & SCF_DO_STCLASS) {
-               int value = 0;
-               data->start_class->flags &= ~ANYOF_EOS; /* No match on empty */
-               if (flags & SCF_DO_STCLASS_AND) {
-                    for (value = 0; value < 256; value++)
-                        if (!is_VERTWS_cp(value))
-                            ANYOF_BITMAP_CLEAR(data->start_class, value);
-                }
-                else {
-                    for (value = 0; value < 256; value++)
-                        if (is_VERTWS_cp(value))
-                            ANYOF_BITMAP_SET(data->start_class, value);
-                }
-                if (flags & SCF_DO_STCLASS_OR)
-                   cl_and(data->start_class, and_withp);
-               flags &= ~SCF_DO_STCLASS;
-            }
-           min += 1;
-           delta += 1;
-            if (flags & SCF_DO_SUBSTR) {
-               SCAN_COMMIT(pRExC_state,data,minlenp);  /* Cannot expect anything... */
-               data->pos_min += 1;
-               data->pos_delta += 1;
-               data->longest = &(data->longest_float);
-           }
-       }
-       else if (OP(scan) == FOLDCHAR) {
-           int d = ARG(scan) == LATIN_SMALL_LETTER_SHARP_S ? 1 : 2;
-           flags &= ~SCF_DO_STCLASS;
-            min += 1;
-            delta += d;
-            if (flags & SCF_DO_SUBSTR) {
-               SCAN_COMMIT(pRExC_state,data,minlenp);  /* Cannot expect anything... */
-               data->pos_min += 1;
-               data->pos_delta += d;
-               data->longest = &(data->longest_float);
-           }
-       }
-       else if (REGNODE_SIMPLE(OP(scan))) {
-           int value = 0;
-
-           if (flags & SCF_DO_SUBSTR) {
-               SCAN_COMMIT(pRExC_state,data,minlenp);
-               data->pos_min++;
-           }
-           min++;
-           if (flags & SCF_DO_STCLASS) {
-               data->start_class->flags &= ~ANYOF_EOS; /* No match on empty */
-
-               /* Some of the logic below assumes that switching
-                  locale on will only add false positives. */
-               switch (PL_regkind[OP(scan)]) {
-               case SANY:
-               default:
-                 do_default:
-                   /* Perl_croak(aTHX_ "panic: unexpected simple REx opcode %d", OP(scan)); */
-                   if (flags & SCF_DO_STCLASS_OR) /* Allow everything */
-                       cl_anything(pRExC_state, data->start_class);
-                   break;
-               case REG_ANY:
-                   if (OP(scan) == SANY)
-                       goto do_default;
-                   if (flags & SCF_DO_STCLASS_OR) { /* Everything but \n */
-                       value = (ANYOF_BITMAP_TEST(data->start_class,'\n')
-                                || ANYOF_CLASS_TEST_ANY_SET(data->start_class));
-                       cl_anything(pRExC_state, data->start_class);
-                   }
-                   if (flags & SCF_DO_STCLASS_AND || !value)
-                       ANYOF_BITMAP_CLEAR(data->start_class,'\n');
-                   break;
-               case ANYOF:
-                   if (flags & SCF_DO_STCLASS_AND)
-                       cl_and(data->start_class,
-                              (struct regnode_charclass_class*)scan);
-                   else
-                       cl_or(pRExC_state, data->start_class,
-                             (struct regnode_charclass_class*)scan);
-                   break;
-               case ALNUM:
-                   if (flags & SCF_DO_STCLASS_AND) {
-                       if (!(data->start_class->flags & ANYOF_LOCALE)) {
-                           ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NALNUM);
-                            if (OP(scan) == ALNUMU) {
-                                for (value = 0; value < 256; value++) {
-                                    if (!isWORDCHAR_L1(value)) {
-                                        ANYOF_BITMAP_CLEAR(data->start_class, value);
-                                    }
-                                }
-                            } else {
-                                for (value = 0; value < 256; value++) {
-                                    if (!isALNUM(value)) {
-                                        ANYOF_BITMAP_CLEAR(data->start_class, value);
-                                    }
-                                }
-                            }
-                       }
-                   }
-                   else {
-                       if (data->start_class->flags & ANYOF_LOCALE)
-                           ANYOF_CLASS_SET(data->start_class,ANYOF_ALNUM);
-                        else if (OP(scan) == ALNUMU) {
-                            for (value = 0; value < 256; value++) {
-                                if (isWORDCHAR_L1(value)) {
-                                    ANYOF_BITMAP_SET(data->start_class, value);
-                                }
-                            }
-                        } else {
-                            for (value = 0; value < 256; value++) {
-                                if (isALNUM(value)) {
-                                    ANYOF_BITMAP_SET(data->start_class, value);
-                                }
-                            }
-                        }
-                   }
-                   break;
-               case NALNUM:
-                   if (flags & SCF_DO_STCLASS_AND) {
-                       if (!(data->start_class->flags & ANYOF_LOCALE)) {
-                           ANYOF_CLASS_CLEAR(data->start_class,ANYOF_ALNUM);
-                            if (OP(scan) == NALNUMU) {
-                                for (value = 0; value < 256; value++) {
-                                    if (isWORDCHAR_L1(value)) {
-                                        ANYOF_BITMAP_CLEAR(data->start_class, value);
-                                    }
-                                }
-                            } else {
-                                for (value = 0; value < 256; value++) {
-                                    if (isALNUM(value)) {
-                                        ANYOF_BITMAP_CLEAR(data->start_class, value);
-                                    }
-                                }
-                           }
-                       }
-                   }
-                   else {
-                       if (data->start_class->flags & ANYOF_LOCALE)
-                           ANYOF_CLASS_SET(data->start_class,ANYOF_NALNUM);
-                       else {
-                            if (OP(scan) == NALNUMU) {
-                                for (value = 0; value < 256; value++) {
-                                    if (! isWORDCHAR_L1(value)) {
-                                        ANYOF_BITMAP_SET(data->start_class, value);
-                                    }
-                                }
-                            } else {
-                                for (value = 0; value < 256; value++) {
-                                    if (! isALNUM(value)) {
-                                        ANYOF_BITMAP_SET(data->start_class, value);
-                                    }
-                                }
-                           }
-                       }
-                   }
-                   break;
-               case SPACE:
-                   if (flags & SCF_DO_STCLASS_AND) {
-                       if (!(data->start_class->flags & ANYOF_LOCALE)) {
-                           ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NSPACE);
-                           if (OP(scan) == SPACEU) {
-                                for (value = 0; value < 256; value++) {
-                                    if (!isSPACE_L1(value)) {
-                                        ANYOF_BITMAP_CLEAR(data->start_class, value);
-                                    }
-                                }
-                            } else {
-                                for (value = 0; value < 256; value++) {
-                                    if (!isSPACE(value)) {
-                                        ANYOF_BITMAP_CLEAR(data->start_class, value);
-                                    }
-                                }
-                            }
-                       }
-                   }
-                   else {
-                        if (data->start_class->flags & ANYOF_LOCALE) {
-                           ANYOF_CLASS_SET(data->start_class,ANYOF_SPACE);
-                        }
-                        else if (OP(scan) == SPACEU) {
-                            for (value = 0; value < 256; value++) {
-                                if (isSPACE_L1(value)) {
-                                    ANYOF_BITMAP_SET(data->start_class, value);
-                                }
-                            }
-                        } else {
-                            for (value = 0; value < 256; value++) {
-                                if (isSPACE(value)) {
-                                    ANYOF_BITMAP_SET(data->start_class, value);
-                                }
-                            }
-                       }
-                   }
-                   break;
-               case NSPACE:
-                   if (flags & SCF_DO_STCLASS_AND) {
-                       if (!(data->start_class->flags & ANYOF_LOCALE)) {
-                           ANYOF_CLASS_CLEAR(data->start_class,ANYOF_SPACE);
-                            if (OP(scan) == NSPACEU) {
-                                for (value = 0; value < 256; value++) {
-                                    if (isSPACE_L1(value)) {
-                                        ANYOF_BITMAP_CLEAR(data->start_class, value);
-                                    }
-                                }
-                            } else {
-                                for (value = 0; value < 256; value++) {
-                                    if (isSPACE(value)) {
-                                        ANYOF_BITMAP_CLEAR(data->start_class, value);
-                                    }
-                                }
-                            }
-                       }
-                   }
-                   else {
-                       if (data->start_class->flags & ANYOF_LOCALE)
-                           ANYOF_CLASS_SET(data->start_class,ANYOF_NSPACE);
-                        else if (OP(scan) == NSPACEU) {
-                            for (value = 0; value < 256; value++) {
-                                if (!isSPACE_L1(value)) {
-                                    ANYOF_BITMAP_SET(data->start_class, value);
-                                }
-                            }
-                        }
-                        else {
-                            for (value = 0; value < 256; value++) {
-                                if (!isSPACE(value)) {
-                                    ANYOF_BITMAP_SET(data->start_class, value);
-                                }
-                            }
-                        }
-                   }
-                   break;
-               case DIGIT:
-                   if (flags & SCF_DO_STCLASS_AND) {
-                       ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NDIGIT);
-                       for (value = 0; value < 256; value++)
-                           if (!isDIGIT(value))
-                               ANYOF_BITMAP_CLEAR(data->start_class, value);
-                   }
-                   else {
-                       if (data->start_class->flags & ANYOF_LOCALE)
-                           ANYOF_CLASS_SET(data->start_class,ANYOF_DIGIT);
-                       else {
-                           for (value = 0; value < 256; value++)
-                               if (isDIGIT(value))
-                                   ANYOF_BITMAP_SET(data->start_class, value);
-                       }
-                   }
-                   break;
-               case NDIGIT:
-                   if (flags & SCF_DO_STCLASS_AND) {
-                       ANYOF_CLASS_CLEAR(data->start_class,ANYOF_DIGIT);
-                       for (value = 0; value < 256; value++)
-                           if (isDIGIT(value))
-                               ANYOF_BITMAP_CLEAR(data->start_class, value);
-                   }
-                   else {
-                       if (data->start_class->flags & ANYOF_LOCALE)
-                           ANYOF_CLASS_SET(data->start_class,ANYOF_NDIGIT);
-                       else {
-                           for (value = 0; value < 256; value++)
-                               if (!isDIGIT(value))
-                                   ANYOF_BITMAP_SET(data->start_class, value);
-                       }
-                   }
-                   break;
-               CASE_SYNST_FNC(VERTWS);
-               CASE_SYNST_FNC(HORIZWS);
-               
-               }
-               if (flags & SCF_DO_STCLASS_OR)
-                   cl_and(data->start_class, and_withp);
-               flags &= ~SCF_DO_STCLASS;
-           }
-       }
-       else if (PL_regkind[OP(scan)] == EOL && flags & SCF_DO_SUBSTR) {
-           data->flags |= (OP(scan) == MEOL
-                           ? SF_BEFORE_MEOL
-                           : SF_BEFORE_SEOL);
-       }
-       else if (  PL_regkind[OP(scan)] == BRANCHJ
-                /* Lookbehind, or need to calculate parens/evals/stclass: */
-                  && (scan->flags || data || (flags & SCF_DO_STCLASS))
-                  && (OP(scan) == IFMATCH || OP(scan) == UNLESSM)) {
-            if ( !PERL_ENABLE_POSITIVE_ASSERTION_STUDY 
-                || OP(scan) == UNLESSM )
-            {
-                /* Negative Lookahead/lookbehind
-                   In this case we can't do fixed string optimisation.
-                */
-
-                I32 deltanext, minnext, fake = 0;
-                regnode *nscan;
-                struct regnode_charclass_class intrnl;
-                int f = 0;
-
-                data_fake.flags = 0;
-                if (data) {
-                    data_fake.whilem_c = data->whilem_c;
-                    data_fake.last_closep = data->last_closep;
-               }
-                else
-                    data_fake.last_closep = &fake;
-               data_fake.pos_delta = delta;
-                if ( flags & SCF_DO_STCLASS && !scan->flags
-                     && OP(scan) == IFMATCH ) { /* Lookahead */
-                    cl_init(pRExC_state, &intrnl);
-                    data_fake.start_class = &intrnl;
-                    f |= SCF_DO_STCLASS_AND;
-               }
-                if (flags & SCF_WHILEM_VISITED_POS)
-                    f |= SCF_WHILEM_VISITED_POS;
-                next = regnext(scan);
-                nscan = NEXTOPER(NEXTOPER(scan));
-                minnext = study_chunk(pRExC_state, &nscan, minlenp, &deltanext, 
-                    last, &data_fake, stopparen, recursed, NULL, f, depth+1);
-                if (scan->flags) {
-                    if (deltanext) {
-                       FAIL("Variable length lookbehind not implemented");
-                    }
-                    else if (minnext > (I32)U8_MAX) {
-                       FAIL2("Lookbehind longer than %"UVuf" not implemented", (UV)U8_MAX);
-                    }
-                    scan->flags = (U8)minnext;
-                }
-                if (data) {
-                    if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
-                        pars++;
-                    if (data_fake.flags & SF_HAS_EVAL)
-                        data->flags |= SF_HAS_EVAL;
-                    data->whilem_c = data_fake.whilem_c;
-                }
-                if (f & SCF_DO_STCLASS_AND) {
-                   if (flags & SCF_DO_STCLASS_OR) {
-                       /* OR before, AND after: ideally we would recurse with
-                        * data_fake to get the AND applied by study of the
-                        * remainder of the pattern, and then derecurse;
-                        * *** HACK *** for now just treat as "no information".
-                        * See [perl #56690].
-                        */
-                       cl_init(pRExC_state, data->start_class);
-                   }  else {
-                       /* AND before and after: combine and continue */
-                       const int was = (data->start_class->flags & ANYOF_EOS);
-
-                       cl_and(data->start_class, &intrnl);
-                       if (was)
-                           data->start_class->flags |= ANYOF_EOS;
-                   }
-                }
-           }
-#if PERL_ENABLE_POSITIVE_ASSERTION_STUDY
-            else {
-                /* Positive Lookahead/lookbehind
-                   In this case we can do fixed string optimisation,
-                   but we must be careful about it. Note in the case of
-                   lookbehind the positions will be offset by the minimum
-                   length of the pattern, something we won't know about
-                   until after the recurse.
-                */
-                I32 deltanext, fake = 0;
-                regnode *nscan;
-                struct regnode_charclass_class intrnl;
-                int f = 0;
-                /* We use SAVEFREEPV so that when the full compile 
-                    is finished perl will clean up the allocated 
-                    minlens when it's all done. This way we don't
-                    have to worry about freeing them when we know
-                    they wont be used, which would be a pain.
-                 */
-                I32 *minnextp;
-                Newx( minnextp, 1, I32 );
-                SAVEFREEPV(minnextp);
-
-                if (data) {
-                    StructCopy(data, &data_fake, scan_data_t);
-                    if ((flags & SCF_DO_SUBSTR) && data->last_found) {
-                        f |= SCF_DO_SUBSTR;
-                        if (scan->flags) 
-                            SCAN_COMMIT(pRExC_state, &data_fake,minlenp);
-                        data_fake.last_found=newSVsv(data->last_found);
-                    }
-                }
-                else
-                    data_fake.last_closep = &fake;
-                data_fake.flags = 0;
-               data_fake.pos_delta = delta;
-                if (is_inf)
-                   data_fake.flags |= SF_IS_INF;
-                if ( flags & SCF_DO_STCLASS && !scan->flags
-                     && OP(scan) == IFMATCH ) { /* Lookahead */
-                    cl_init(pRExC_state, &intrnl);
-                    data_fake.start_class = &intrnl;
-                    f |= SCF_DO_STCLASS_AND;
-                }
-                if (flags & SCF_WHILEM_VISITED_POS)
-                    f |= SCF_WHILEM_VISITED_POS;
-                next = regnext(scan);
-                nscan = NEXTOPER(NEXTOPER(scan));
-
-                *minnextp = study_chunk(pRExC_state, &nscan, minnextp, &deltanext, 
-                    last, &data_fake, stopparen, recursed, NULL, f,depth+1);
-                if (scan->flags) {
-                    if (deltanext) {
-                       FAIL("Variable length lookbehind not implemented");
-                    }
-                    else if (*minnextp > (I32)U8_MAX) {
-                       FAIL2("Lookbehind longer than %"UVuf" not implemented", (UV)U8_MAX);
-                    }
-                    scan->flags = (U8)*minnextp;
-                }
-
-                *minnextp += min;
-
-                if (f & SCF_DO_STCLASS_AND) {
-                    const int was = (data->start_class->flags & ANYOF_EOS);
-
-                    cl_and(data->start_class, &intrnl);
-                    if (was)
-                        data->start_class->flags |= ANYOF_EOS;
-                }
-                if (data) {
-                    if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
-                        pars++;
-                    if (data_fake.flags & SF_HAS_EVAL)
-                        data->flags |= SF_HAS_EVAL;
-                    data->whilem_c = data_fake.whilem_c;
-                    if ((flags & SCF_DO_SUBSTR) && data_fake.last_found) {
-                        if (RExC_rx->minlen<*minnextp)
-                            RExC_rx->minlen=*minnextp;
-                        SCAN_COMMIT(pRExC_state, &data_fake, minnextp);
-                        SvREFCNT_dec(data_fake.last_found);
-                        
-                        if ( data_fake.minlen_fixed != minlenp ) 
-                        {
-                            data->offset_fixed= data_fake.offset_fixed;
-                            data->minlen_fixed= data_fake.minlen_fixed;
-                            data->lookbehind_fixed+= scan->flags;
-                        }
-                        if ( data_fake.minlen_float != minlenp )
-                        {
-                            data->minlen_float= data_fake.minlen_float;
-                            data->offset_float_min=data_fake.offset_float_min;
-                            data->offset_float_max=data_fake.offset_float_max;
-                            data->lookbehind_float+= scan->flags;
-                        }
-                    }
-                }
-
-
-           }
-#endif
-       }
-       else if (OP(scan) == OPEN) {
-           if (stopparen != (I32)ARG(scan))
-               pars++;
-       }
-       else if (OP(scan) == CLOSE) {
-           if (stopparen == (I32)ARG(scan)) {
-               break;
-           }
-           if ((I32)ARG(scan) == is_par) {
-               next = regnext(scan);
-
-               if ( next && (OP(next) != WHILEM) && next < last)
-                   is_par = 0;         /* Disable optimization */
-           }
-           if (data)
-               *(data->last_closep) = ARG(scan);
-       }
-       else if (OP(scan) == EVAL) {
-               if (data)
-                   data->flags |= SF_HAS_EVAL;
-       }
-       else if ( PL_regkind[OP(scan)] == ENDLIKE ) {
-           if (flags & SCF_DO_SUBSTR) {
-               SCAN_COMMIT(pRExC_state,data,minlenp);
-               flags &= ~SCF_DO_SUBSTR;
-           }
-           if (data && OP(scan)==ACCEPT) {
-               data->flags |= SCF_SEEN_ACCEPT;
-               if (stopmin > min)
-                   stopmin = min;
-           }
-       }
-       else if (OP(scan) == LOGICAL && scan->flags == 2) /* Embedded follows */
-       {
-               if (flags & SCF_DO_SUBSTR) {
-                   SCAN_COMMIT(pRExC_state,data,minlenp);
-                   data->longest = &(data->longest_float);
-               }
-               is_inf = is_inf_internal = 1;
-               if (flags & SCF_DO_STCLASS_OR) /* Allow everything */
-                   cl_anything(pRExC_state, data->start_class);
-               flags &= ~SCF_DO_STCLASS;
-       }
-       else if (OP(scan) == GPOS) {
-           if (!(RExC_rx->extflags & RXf_GPOS_FLOAT) &&
-               !(delta || is_inf || (data && data->pos_delta))) 
-           {
-               if (!(RExC_rx->extflags & RXf_ANCH) && (flags & SCF_DO_SUBSTR))
-                   RExC_rx->extflags |= RXf_ANCH_GPOS;
-               if (RExC_rx->gofs < (U32)min)
-                   RExC_rx->gofs = min;
-            } else {
-                RExC_rx->extflags |= RXf_GPOS_FLOAT;
-                RExC_rx->gofs = 0;
-            }      
-       }
-#ifdef TRIE_STUDY_OPT
-#ifdef FULL_TRIE_STUDY
-        else if (PL_regkind[OP(scan)] == TRIE) {
-            /* NOTE - There is similar code to this block above for handling
-               BRANCH nodes on the initial study.  If you change stuff here
-               check there too. */
-            regnode *trie_node= scan;
-            regnode *tail= regnext(scan);
-            reg_trie_data *trie = (reg_trie_data*)RExC_rxi->data->data[ ARG(scan) ];
-            I32 max1 = 0, min1 = I32_MAX;
-            struct regnode_charclass_class accum;
-
-            if (flags & SCF_DO_SUBSTR) /* XXXX Add !SUSPEND? */
-                SCAN_COMMIT(pRExC_state, data,minlenp); /* Cannot merge strings after this. */
-            if (flags & SCF_DO_STCLASS)
-                cl_init_zero(pRExC_state, &accum);
-                
-            if (!trie->jump) {
-                min1= trie->minlen;
-                max1= trie->maxlen;
-            } else {
-                const regnode *nextbranch= NULL;
-                U32 word;
-                
-                for ( word=1 ; word <= trie->wordcount ; word++) 
-                {
-                    I32 deltanext=0, minnext=0, f = 0, fake;
-                    struct regnode_charclass_class this_class;
-                    
-                    data_fake.flags = 0;
-                    if (data) {
-                        data_fake.whilem_c = data->whilem_c;
-                        data_fake.last_closep = data->last_closep;
-                    }
-                    else
-                        data_fake.last_closep = &fake;
-                   data_fake.pos_delta = delta;
-                    if (flags & SCF_DO_STCLASS) {
-                        cl_init(pRExC_state, &this_class);
-                        data_fake.start_class = &this_class;
-                        f = SCF_DO_STCLASS_AND;
-                    }
-                    if (flags & SCF_WHILEM_VISITED_POS)
-                        f |= SCF_WHILEM_VISITED_POS;
-    
-                    if (trie->jump[word]) {
-                        if (!nextbranch)
-                            nextbranch = trie_node + trie->jump[0];
-                        scan= trie_node + trie->jump[word];
-                        /* We go from the jump point to the branch that follows
-                           it. Note this means we need the vestigal unused branches
-                           even though they arent otherwise used.
-                         */
-                        minnext = study_chunk(pRExC_state, &scan, minlenp, 
-                            &deltanext, (regnode *)nextbranch, &data_fake, 
-                            stopparen, recursed, NULL, f,depth+1);
-                    }
-                    if (nextbranch && PL_regkind[OP(nextbranch)]==BRANCH)
-                        nextbranch= regnext((regnode*)nextbranch);
-                    
-                    if (min1 > (I32)(minnext + trie->minlen))
-                        min1 = minnext + trie->minlen;
-                    if (max1 < (I32)(minnext + deltanext + trie->maxlen))
-                        max1 = minnext + deltanext + trie->maxlen;
-                    if (deltanext == I32_MAX)
-                        is_inf = is_inf_internal = 1;
-                    
-                    if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
-                        pars++;
-                    if (data_fake.flags & SCF_SEEN_ACCEPT) {
-                        if ( stopmin > min + min1) 
-                           stopmin = min + min1;
-                       flags &= ~SCF_DO_SUBSTR;
-                       if (data)
-                           data->flags |= SCF_SEEN_ACCEPT;
-                   }
-                    if (data) {
-                        if (data_fake.flags & SF_HAS_EVAL)
-                            data->flags |= SF_HAS_EVAL;
-                        data->whilem_c = data_fake.whilem_c;
-                    }
-                    if (flags & SCF_DO_STCLASS)
-                        cl_or(pRExC_state, &accum, &this_class);
-                }
-            }
-            if (flags & SCF_DO_SUBSTR) {
-                data->pos_min += min1;
-                data->pos_delta += max1 - min1;
-                if (max1 != min1 || is_inf)
-                    data->longest = &(data->longest_float);
-            }
-            min += min1;
-            delta += max1 - min1;
-            if (flags & SCF_DO_STCLASS_OR) {
-                cl_or(pRExC_state, data->start_class, &accum);
-                if (min1) {
-                    cl_and(data->start_class, and_withp);
-                    flags &= ~SCF_DO_STCLASS;
-                }
-            }
-            else if (flags & SCF_DO_STCLASS_AND) {
-                if (min1) {
-                    cl_and(data->start_class, &accum);
-                    flags &= ~SCF_DO_STCLASS;
-                }
-                else {
-                    /* Switch to OR mode: cache the old value of
-                     * data->start_class */
-                   INIT_AND_WITHP;
-                    StructCopy(data->start_class, and_withp,
-                               struct regnode_charclass_class);
-                    flags &= ~SCF_DO_STCLASS_AND;
-                    StructCopy(&accum, data->start_class,
-                               struct regnode_charclass_class);
-                    flags |= SCF_DO_STCLASS_OR;
-                    data->start_class->flags |= ANYOF_EOS;
-                }
-            }
-            scan= tail;
-            continue;
-        }
-#else
-       else if (PL_regkind[OP(scan)] == TRIE) {
-           reg_trie_data *trie = (reg_trie_data*)RExC_rxi->data->data[ ARG(scan) ];
-           U8*bang=NULL;
-           
-           min += trie->minlen;
-           delta += (trie->maxlen - trie->minlen);
-           flags &= ~SCF_DO_STCLASS; /* xxx */
-            if (flags & SCF_DO_SUBSTR) {
-               SCAN_COMMIT(pRExC_state,data,minlenp);  /* Cannot expect anything... */
-               data->pos_min += trie->minlen;
-               data->pos_delta += (trie->maxlen - trie->minlen);
-               if (trie->maxlen != trie->minlen)
-                   data->longest = &(data->longest_float);
-           }
-           if (trie->jump) /* no more substrings -- for now /grr*/
-               flags &= ~SCF_DO_SUBSTR; 
-       }
-#endif /* old or new */
-#endif /* TRIE_STUDY_OPT */    
-
-       /* Else: zero-length, ignore. */
-       scan = regnext(scan);
-    }
-    if (frame) {
-        last = frame->last;
-        scan = frame->next;
-        stopparen = frame->stop;
-        frame = frame->prev;
-        goto fake_study_recurse;
-    }
-
-  finish:
-    assert(!frame);
-    DEBUG_STUDYDATA("pre-fin:",data,depth);
-
-    *scanp = scan;
-    *deltap = is_inf_internal ? I32_MAX : delta;
-    if (flags & SCF_DO_SUBSTR && is_inf)
-       data->pos_delta = I32_MAX - data->pos_min;
-    if (is_par > (I32)U8_MAX)
-       is_par = 0;
-    if (is_par && pars==1 && data) {
-       data->flags |= SF_IN_PAR;
-       data->flags &= ~SF_HAS_PAR;
-    }
-    else if (pars && data) {
-       data->flags |= SF_HAS_PAR;
-       data->flags &= ~SF_IN_PAR;
-    }
-    if (flags & SCF_DO_STCLASS_OR)
-       cl_and(data->start_class, and_withp);
-    if (flags & SCF_TRIE_RESTUDY)
-        data->flags |=         SCF_TRIE_RESTUDY;
-    
-    DEBUG_STUDYDATA("post-fin:",data,depth);
-    
-    return min < stopmin ? min : stopmin;
-}
-
-STATIC U32
-S_add_data(RExC_state_t *pRExC_state, U32 n, const char *s)
-{
-    U32 count = RExC_rxi->data ? RExC_rxi->data->count : 0;
-
-    PERL_ARGS_ASSERT_ADD_DATA;
-
-    Renewc(RExC_rxi->data,
-          sizeof(*RExC_rxi->data) + sizeof(void*) * (count + n - 1),
-          char, struct reg_data);
-    if(count)
-       Renew(RExC_rxi->data->what, count + n, U8);
-    else
-       Newx(RExC_rxi->data->what, n, U8);
-    RExC_rxi->data->count = count + n;
-    Copy(s, RExC_rxi->data->what + count, n, U8);
-    return count;
-}
-
-/*XXX: todo make this not included in a non debugging perl */
-#ifndef PERL_IN_XSUB_RE
-void
-Perl_reginitcolors(pTHX)
-{
-    dVAR;
-    const char * const s = PerlEnv_getenv("PERL_RE_COLORS");
-    if (s) {
-       char *t = savepv(s);
-       int i = 0;
-       PL_colors[0] = t;
-       while (++i < 6) {
-           t = strchr(t, '\t');
-           if (t) {
-               *t = '\0';
-               PL_colors[i] = ++t;
-           }
-           else
-               PL_colors[i] = t = (char *)"";
-       }
-    } else {
-       int i = 0;
-       while (i < 6)
-           PL_colors[i++] = (char *)"";
-    }
-    PL_colorset = 1;
-}
-#endif
-
-
-#ifdef TRIE_STUDY_OPT
-#define CHECK_RESTUDY_GOTO                                  \
-        if (                                                \
-              (data.flags & SCF_TRIE_RESTUDY)               \
-              && ! restudied++                              \
-        )     goto reStudy
-#else
-#define CHECK_RESTUDY_GOTO
-#endif        
-
-/*
- - pregcomp - compile a regular expression into internal code
- *
- * We can't allocate space until we know how big the compiled form will be,
- * but we can't compile it (and thus know how big it is) until we've got a
- * place to put the code.  So we cheat:  we compile it twice, once with code
- * generation turned off and size counting turned on, and once "for real".
- * This also means that we don't allocate space until we are sure that the
- * thing really will compile successfully, and we never have to move the
- * code and thus invalidate pointers into it.  (Note that it has to be in
- * one piece because free() must be able to free it all.) [NB: not true in perl]
- *
- * Beware that the optimization-preparation code in here knows about some
- * of the structure of the compiled regexp.  [I'll say.]
- */
-
-
-
-#ifndef PERL_IN_XSUB_RE
-#define RE_ENGINE_PTR &reh_regexp_engine
-#else
-extern const struct regexp_engine my_reg_engine;
-#define RE_ENGINE_PTR &my_reg_engine
-#endif
-
-#ifndef PERL_IN_XSUB_RE 
-REGEXP *
-Perl_pregcomp(pTHX_ SV * const pattern, const U32 flags)
-{
-    dVAR;
-    HV * const table = GvHV(PL_hintgv);
-
-    PERL_ARGS_ASSERT_PREGCOMP;
-
-    /* Dispatch a request to compile a regexp to correct 
-       regexp engine. */
-    if (table) {
-        SV **ptr= hv_fetchs(table, "regcomp", FALSE);
-        GET_RE_DEBUG_FLAGS_DECL;
-        if (ptr && SvIOK(*ptr) && SvIV(*ptr)) {
-            const regexp_engine *eng=INT2PTR(regexp_engine*,SvIV(*ptr));
-            DEBUG_COMPILE_r({
-                PerlIO_printf(Perl_debug_log, "Using engine %"UVxf"\n",
-                    SvIV(*ptr));
-            });            
-            return CALLREGCOMP_ENG(eng, pattern, flags);
-        } 
-    }
-    return Perl_re_compile(aTHX_ pattern, flags);
-}
-#endif
-
-REGEXP *
-Perl_re_compile(pTHX_ SV * const pattern, U32 orig_pm_flags)
-{
-    dVAR;
-    REGEXP *rx;
-    struct regexp *r;
-    register regexp_internal *ri;
-    STRLEN plen;
-    char  *exp;
-    char* xend;
-    regnode *scan;
-    I32 flags;
-    I32 minlen = 0;
-    U32 pm_flags;
-
-    /* these are all flags - maybe they should be turned
-     * into a single int with different bit masks */
-    I32 sawlookahead = 0;
-    I32 sawplus = 0;
-    I32 sawopen = 0;
-    bool used_setjump = FALSE;
-
-    U8 jump_ret = 0;
-    dJMPENV;
-    scan_data_t data;
-    RExC_state_t RExC_state;
-    RExC_state_t * const pRExC_state = &RExC_state;
-#ifdef TRIE_STUDY_OPT    
-    int restudied;
-    RExC_state_t copyRExC_state;
-#endif    
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_RE_COMPILE;
-
-    DEBUG_r(if (!PL_colorset) reginitcolors());
-
-    RExC_utf8 = RExC_orig_utf8 = SvUTF8(pattern);
-
-    /****************** LONG JUMP TARGET HERE***********************/
-    /* Longjmp back to here if have to switch in midstream to utf8 */
-    if (! RExC_orig_utf8) {
-       JMPENV_PUSH(jump_ret);
-       used_setjump = TRUE;
-    }
-
-    if (jump_ret == 0) {    /* First time through */
-       exp = SvPV(pattern, plen);
-       xend = exp + plen;
-       /* ignore the utf8ness if the pattern is 0 length */
-       if (plen == 0) {
-           RExC_utf8 = RExC_orig_utf8 = 0;
-       }
-
-        DEBUG_COMPILE_r({
-            SV *dsv= sv_newmortal();
-            RE_PV_QUOTED_DECL(s, RExC_utf8,
-                dsv, exp, plen, 60);
-            PerlIO_printf(Perl_debug_log, "%sCompiling REx%s %s\n",
-                           PL_colors[4],PL_colors[5],s);
-        });
-    }
-    else {  /* longjumped back */
-        STRLEN len = plen;
-
-        /* If the cause for the longjmp was other than changing to utf8, pop
-         * our own setjmp, and longjmp to the correct handler */
-       if (jump_ret != UTF8_LONGJMP) {
-           JMPENV_POP;
-           JMPENV_JUMP(jump_ret);
-       }
-
-       GET_RE_DEBUG_FLAGS;
-
-        /* It's possible to write a regexp in ascii that represents Unicode
-        codepoints outside of the byte range, such as via \x{100}. If we
-        detect such a sequence we have to convert the entire pattern to utf8
-        and then recompile, as our sizing calculation will have been based
-        on 1 byte == 1 character, but we will need to use utf8 to encode
-        at least some part of the pattern, and therefore must convert the whole
-        thing.
-        -- dmq */
-        DEBUG_PARSE_r(PerlIO_printf(Perl_debug_log,
-           "UTF8 mismatch! Converting to utf8 for resizing and compile\n"));
-        exp = (char*)Perl_bytes_to_utf8(aTHX_ (U8*)SvPV(pattern, plen), &len);
-        xend = exp + len;
-        RExC_orig_utf8 = RExC_utf8 = 1;
-        SAVEFREEPV(exp);
-    }
-
-#ifdef TRIE_STUDY_OPT
-    restudied = 0;
-#endif
-
-    /* Set to use unicode semantics if the pattern is in utf8 and has the
-     * 'depends' charset specified, as it means unicode when utf8  */
-    pm_flags = orig_pm_flags;
-
-    if (RExC_utf8 && get_regex_charset(pm_flags) == REGEX_DEPENDS_CHARSET) {
-       set_regex_charset(&pm_flags, REGEX_UNICODE_CHARSET);
-    }
-
-    RExC_precomp = exp;
-    RExC_flags = pm_flags;
-    RExC_sawback = 0;
-
-    RExC_seen = 0;
-    RExC_in_lookbehind = 0;
-    RExC_seen_zerolen = *exp == '^' ? -1 : 0;
-    RExC_seen_evals = 0;
-    RExC_extralen = 0;
-
-    /* First pass: determine size, legality. */
-    RExC_parse = exp;
-    RExC_start = exp;
-    RExC_end = xend;
-    RExC_naughty = 0;
-    RExC_npar = 1;
-    RExC_nestroot = 0;
-    RExC_size = 0L;
-    RExC_emit = &PL_regdummy;
-    RExC_whilem_seen = 0;
-    RExC_open_parens = NULL;
-    RExC_close_parens = NULL;
-    RExC_opend = NULL;
-    RExC_paren_names = NULL;
-#ifdef DEBUGGING
-    RExC_paren_name_list = NULL;
-#endif
-    RExC_recurse = NULL;
-    RExC_recurse_count = 0;
-
-#if 0 /* REGC() is (currently) a NOP at the first pass.
-       * Clever compilers notice this and complain. --jhi */
-    REGC((U8)REG_MAGIC, (char*)RExC_emit);
-#endif
-    DEBUG_PARSE_r(PerlIO_printf(Perl_debug_log, "Starting first pass (sizing)\n"));
-    if (reg(pRExC_state, 0, &flags,1) == NULL) {
-       RExC_precomp = NULL;
-       return(NULL);
-    }
-
-    /* Here, finished first pass.  Get rid of any added setjmp */
-    if (used_setjump) {
-       JMPENV_POP;
-    }
-    DEBUG_PARSE_r({
-        PerlIO_printf(Perl_debug_log, 
-            "Required size %"IVdf" nodes\n"
-            "Starting second pass (creation)\n", 
-            (IV)RExC_size);
-        RExC_lastnum=0; 
-        RExC_lastparse=NULL; 
-    });
-    /* Small enough for pointer-storage convention?
-       If extralen==0, this means that we will not need long jumps. */
-    if (RExC_size >= 0x10000L && RExC_extralen)
-        RExC_size += RExC_extralen;
-    else
-       RExC_extralen = 0;
-    if (RExC_whilem_seen > 15)
-       RExC_whilem_seen = 15;
-
-    /* Allocate space and zero-initialize. Note, the two step process 
-       of zeroing when in debug mode, thus anything assigned has to 
-       happen after that */
-    rx = (REGEXP*) newSV_type(SVt_REGEXP);
-    r = (struct regexp*)SvANY(rx);
-    Newxc(ri, sizeof(regexp_internal) + (unsigned)RExC_size * sizeof(regnode),
-        char, regexp_internal);
-    if ( r == NULL || ri == NULL )
-       FAIL("Regexp out of space");
-#ifdef DEBUGGING
-    /* avoid reading uninitialized memory in DEBUGGING code in study_chunk() */
-    Zero(ri, sizeof(regexp_internal) + (unsigned)RExC_size * sizeof(regnode), char);
-#else 
-    /* bulk initialize base fields with 0. */
-    Zero(ri, sizeof(regexp_internal), char);        
-#endif
-
-    /* non-zero initialization begins here */
-    RXi_SET( r, ri );
-    r->engine= RE_ENGINE_PTR;
-    r->extflags = pm_flags;
-    {
-        bool has_p     = ((r->extflags & RXf_PMf_KEEPCOPY) == RXf_PMf_KEEPCOPY);
-        bool has_charset = (get_regex_charset(r->extflags) != REGEX_DEPENDS_CHARSET);
-
-        /* The caret is output if there are any defaults: if not all the STD
-         * flags are set, or if no character set specifier is needed */
-        bool has_default =
-                    (((r->extflags & RXf_PMf_STD_PMMOD) != RXf_PMf_STD_PMMOD)
-                    || ! has_charset);
-       bool has_runon = ((RExC_seen & REG_SEEN_RUN_ON_COMMENT)==REG_SEEN_RUN_ON_COMMENT);
-       U16 reganch = (U16)((r->extflags & RXf_PMf_STD_PMMOD)
-                           >> RXf_PMf_STD_PMMOD_SHIFT);
-       const char *fptr = STD_PAT_MODS;        /*"msix"*/
-       char *p;
-        /* Allocate for the worst case, which is all the std flags are turned
-         * on.  If more precision is desired, we could do a population count of
-         * the flags set.  This could be done with a small lookup table, or by
-         * shifting, masking and adding, or even, when available, assembly
-         * language for a machine-language population count.
-         * We never output a minus, as all those are defaults, so are
-         * covered by the caret */
-       const STRLEN wraplen = plen + has_p + has_runon
-            + has_default       /* If needs a caret */
-
-               /* If needs a character set specifier */
-           + ((has_charset) ? MAX_CHARSET_NAME_LENGTH : 0)
-            + (sizeof(STD_PAT_MODS) - 1)
-            + (sizeof("(?:)") - 1);
-
-        p = sv_grow(MUTABLE_SV(rx), wraplen + 1); /* +1 for the ending NUL */
-       SvPOK_on(rx);
-       SvFLAGS(rx) |= SvUTF8(pattern);
-        *p++='('; *p++='?';
-
-        /* If a default, cover it using the caret */
-        if (has_default) {
-            *p++= DEFAULT_PAT_MOD;
-        }
-        if (has_charset) {
-           STRLEN len;
-           const char* const name = get_regex_charset_name(r->extflags, &len);
-           Copy(name, p, len, char);
-           p += len;
-        }
-        if (has_p)
-            *p++ = KEEPCOPY_PAT_MOD; /*'p'*/
-        {
-            char ch;
-            while((ch = *fptr++)) {
-                if(reganch & 1)
-                    *p++ = ch;
-                reganch >>= 1;
-            }
-        }
-
-        *p++ = ':';
-        Copy(RExC_precomp, p, plen, char);
-       assert ((RX_WRAPPED(rx) - p) < 16);
-       r->pre_prefix = p - RX_WRAPPED(rx);
-        p += plen;
-        if (has_runon)
-            *p++ = '\n';
-        *p++ = ')';
-        *p = 0;
-       SvCUR_set(rx, p - SvPVX_const(rx));
-    }
-
-    r->intflags = 0;
-    r->nparens = RExC_npar - 1;        /* set early to validate backrefs */
-    
-    if (RExC_seen & REG_SEEN_RECURSE) {
-        Newxz(RExC_open_parens, RExC_npar,regnode *);
-        SAVEFREEPV(RExC_open_parens);
-        Newxz(RExC_close_parens,RExC_npar,regnode *);
-        SAVEFREEPV(RExC_close_parens);
-    }
-
-    /* Useful during FAIL. */
-#ifdef RE_TRACK_PATTERN_OFFSETS
-    Newxz(ri->u.offsets, 2*RExC_size+1, U32); /* MJD 20001228 */
-    DEBUG_OFFSETS_r(PerlIO_printf(Perl_debug_log,
-                          "%s %"UVuf" bytes for offset annotations.\n",
-                          ri->u.offsets ? "Got" : "Couldn't get",
-                          (UV)((2*RExC_size+1) * sizeof(U32))));
-#endif
-    SetProgLen(ri,RExC_size);
-    RExC_rx_sv = rx;
-    RExC_rx = r;
-    RExC_rxi = ri;
-    REH_CALL_COMP_BEGIN_HOOK(pRExC_state->rx);
-
-    /* Second pass: emit code. */
-    RExC_flags = pm_flags;     /* don't let top level (?i) bleed */
-    RExC_parse = exp;
-    RExC_end = xend;
-    RExC_naughty = 0;
-    RExC_npar = 1;
-    RExC_emit_start = ri->program;
-    RExC_emit = ri->program;
-    RExC_emit_bound = ri->program + RExC_size + 1;
-
-    /* Store the count of eval-groups for security checks: */
-    RExC_rx->seen_evals = RExC_seen_evals;
-    REGC((U8)REG_MAGIC, (char*) RExC_emit++);
-    if (reg(pRExC_state, 0, &flags,1) == NULL) {
-       ReREFCNT_dec(rx);   
-       return(NULL);
-    }
-    /* XXXX To minimize changes to RE engine we always allocate
-       3-units-long substrs field. */
-    Newx(r->substrs, 1, struct reg_substr_data);
-    if (RExC_recurse_count) {
-        Newxz(RExC_recurse,RExC_recurse_count,regnode *);
-        SAVEFREEPV(RExC_recurse);
-    }
-
-reStudy:
-    r->minlen = minlen = sawlookahead = sawplus = sawopen = 0;
-    Zero(r->substrs, 1, struct reg_substr_data);
-
-#ifdef TRIE_STUDY_OPT
-    if (!restudied) {
-        StructCopy(&zero_scan_data, &data, scan_data_t);
-        copyRExC_state = RExC_state;
-    } else {
-        U32 seen=RExC_seen;
-        DEBUG_OPTIMISE_r(PerlIO_printf(Perl_debug_log,"Restudying\n"));
-        
-        RExC_state = copyRExC_state;
-        if (seen & REG_TOP_LEVEL_BRANCHES) 
-            RExC_seen |= REG_TOP_LEVEL_BRANCHES;
-        else
-            RExC_seen &= ~REG_TOP_LEVEL_BRANCHES;
-        if (data.last_found) {
-            SvREFCNT_dec(data.longest_fixed);
-           SvREFCNT_dec(data.longest_float);
-           SvREFCNT_dec(data.last_found);
-       }
-       StructCopy(&zero_scan_data, &data, scan_data_t);
-    }
-#else
-    StructCopy(&zero_scan_data, &data, scan_data_t);
-#endif    
-
-    /* Dig out information for optimizations. */
-    r->extflags = RExC_flags; /* was pm_op */
-    /*dmq: removed as part of de-PMOP: pm->op_pmflags = RExC_flags; */
-    if (UTF)
-       SvUTF8_on(rx);  /* Unicode in it? */
-    ri->regstclass = NULL;
-    if (RExC_naughty >= 10)    /* Probably an expensive pattern. */
-       r->intflags |= PREGf_NAUGHTY;
-    scan = ri->program + 1;            /* First BRANCH. */
-
-    /* testing for BRANCH here tells us whether there is "must appear"
-       data in the pattern. If there is then we can use it for optimisations */
-    if (!(RExC_seen & REG_TOP_LEVEL_BRANCHES)) { /*  Only one top-level choice. */
-       I32 fake;
-       STRLEN longest_float_length, longest_fixed_length;
-       struct regnode_charclass_class ch_class; /* pointed to by data */
-       int stclass_flag;
-       I32 last_close = 0; /* pointed to by data */
-        regnode *first= scan;
-        regnode *first_next= regnext(first);
-       /*
-        * Skip introductions and multiplicators >= 1
-        * so that we can extract the 'meat' of the pattern that must 
-        * match in the large if() sequence following.
-        * NOTE that EXACT is NOT covered here, as it is normally
-        * picked up by the optimiser separately. 
-        *
-        * This is unfortunate as the optimiser isnt handling lookahead
-        * properly currently.
-        *
-        */
-       while ((OP(first) == OPEN && (sawopen = 1)) ||
-              /* An OR of *one* alternative - should not happen now. */
-           (OP(first) == BRANCH && OP(first_next) != BRANCH) ||
-           /* for now we can't handle lookbehind IFMATCH*/
-           (OP(first) == IFMATCH && !first->flags && (sawlookahead = 1)) ||
-           (OP(first) == PLUS) ||
-           (OP(first) == MINMOD) ||
-              /* An {n,m} with n>0 */
-           (PL_regkind[OP(first)] == CURLY && ARG1(first) > 0) ||
-           (OP(first) == NOTHING && PL_regkind[OP(first_next)] != END ))
-       {
-               /* 
-                * the only op that could be a regnode is PLUS, all the rest
-                * will be regnode_1 or regnode_2.
-                *
-                */
-               if (OP(first) == PLUS)
-                   sawplus = 1;
-               else
-                   first += regarglen[OP(first)];
-               
-               first = NEXTOPER(first);
-               first_next= regnext(first);
-       }
-
-       /* Starting-point info. */
-      again:
-        DEBUG_PEEP("first:",first,0);
-        /* Ignore EXACT as we deal with it later. */
-       if (PL_regkind[OP(first)] == EXACT) {
-           if (OP(first) == EXACT)
-               NOOP;   /* Empty, get anchored substr later. */
-           else
-               ri->regstclass = first;
-       }
-#ifdef TRIE_STCLASS    
-       else if (PL_regkind[OP(first)] == TRIE &&
-               ((reg_trie_data *)ri->data->data[ ARG(first) ])->minlen>0) 
-       {
-           regnode *trie_op;
-           /* this can happen only on restudy */
-           if ( OP(first) == TRIE ) {
-                struct regnode_1 *trieop = (struct regnode_1 *)
-                   PerlMemShared_calloc(1, sizeof(struct regnode_1));
-                StructCopy(first,trieop,struct regnode_1);
-                trie_op=(regnode *)trieop;
-            } else {
-                struct regnode_charclass *trieop = (struct regnode_charclass *)
-                   PerlMemShared_calloc(1, sizeof(struct regnode_charclass));
-                StructCopy(first,trieop,struct regnode_charclass);
-                trie_op=(regnode *)trieop;
-            }
-            OP(trie_op)+=2;
-            make_trie_failtable(pRExC_state, (regnode *)first, trie_op, 0);
-           ri->regstclass = trie_op;
-       }
-#endif 
-       else if (REGNODE_SIMPLE(OP(first)))
-           ri->regstclass = first;
-       else if (PL_regkind[OP(first)] == BOUND ||
-                PL_regkind[OP(first)] == NBOUND)
-           ri->regstclass = first;
-       else if (PL_regkind[OP(first)] == BOL) {
-           r->extflags |= (OP(first) == MBOL
-                          ? RXf_ANCH_MBOL
-                          : (OP(first) == SBOL
-                             ? RXf_ANCH_SBOL
-                             : RXf_ANCH_BOL));
-           first = NEXTOPER(first);
-           goto again;
-       }
-       else if (OP(first) == GPOS) {
-           r->extflags |= RXf_ANCH_GPOS;
-           first = NEXTOPER(first);
-           goto again;
-       }
-       else if ((!sawopen || !RExC_sawback) &&
-           (OP(first) == STAR &&
-           PL_regkind[OP(NEXTOPER(first))] == REG_ANY) &&
-           !(r->extflags & RXf_ANCH) && !(RExC_seen & REG_SEEN_EVAL))
-       {
-           /* turn .* into ^.* with an implied $*=1 */
-           const int type =
-               (OP(NEXTOPER(first)) == REG_ANY)
-                   ? RXf_ANCH_MBOL
-                   : RXf_ANCH_SBOL;
-           r->extflags |= type;
-           r->intflags |= PREGf_IMPLICIT;
-           first = NEXTOPER(first);
-           goto again;
-       }
-       if (sawplus && !sawlookahead && (!sawopen || !RExC_sawback)
-           && !(RExC_seen & REG_SEEN_EVAL)) /* May examine pos and $& */
-           /* x+ must match at the 1st pos of run of x's */
-           r->intflags |= PREGf_SKIP;
-
-       /* Scan is after the zeroth branch, first is atomic matcher. */
-#ifdef TRIE_STUDY_OPT
-       DEBUG_PARSE_r(
-           if (!restudied)
-               PerlIO_printf(Perl_debug_log, "first at %"IVdf"\n",
-                             (IV)(first - scan + 1))
-        );
-#else
-       DEBUG_PARSE_r(
-           PerlIO_printf(Perl_debug_log, "first at %"IVdf"\n",
-               (IV)(first - scan + 1))
-        );
-#endif
-
-
-       /*
-       * If there's something expensive in the r.e., find the
-       * longest literal string that must appear and make it the
-       * regmust.  Resolve ties in favor of later strings, since
-       * the regstart check works with the beginning of the r.e.
-       * and avoiding duplication strengthens checking.  Not a
-       * strong reason, but sufficient in the absence of others.
-       * [Now we resolve ties in favor of the earlier string if
-       * it happens that c_offset_min has been invalidated, since the
-       * earlier string may buy us something the later one won't.]
-       */
-       
-       data.longest_fixed = newSVpvs("");
-       data.longest_float = newSVpvs("");
-       data.last_found = newSVpvs("");
-       data.longest = &(data.longest_fixed);
-       first = scan;
-       if (!ri->regstclass) {
-           cl_init(pRExC_state, &ch_class);
-           data.start_class = &ch_class;
-           stclass_flag = SCF_DO_STCLASS_AND;
-       } else                          /* XXXX Check for BOUND? */
-           stclass_flag = 0;
-       data.last_closep = &last_close;
-        
-       minlen = study_chunk(pRExC_state, &first, &minlen, &fake, scan + RExC_size, /* Up to end */
-            &data, -1, NULL, NULL,
-            SCF_DO_SUBSTR | SCF_WHILEM_VISITED_POS | stclass_flag,0);
-
-       
-        CHECK_RESTUDY_GOTO;
-
-
-       if ( RExC_npar == 1 && data.longest == &(data.longest_fixed)
-            && data.last_start_min == 0 && data.last_end > 0
-            && !RExC_seen_zerolen
-            && !(RExC_seen & REG_SEEN_VERBARG)
-            && (!(RExC_seen & REG_SEEN_GPOS) || (r->extflags & RXf_ANCH_GPOS)))
-           r->extflags |= RXf_CHECK_ALL;
-       scan_commit(pRExC_state, &data,&minlen,0);
-       SvREFCNT_dec(data.last_found);
-
-        /* Note that code very similar to this but for anchored string 
-           follows immediately below, changes may need to be made to both. 
-           Be careful. 
-         */
-       longest_float_length = CHR_SVLEN(data.longest_float);
-       if (longest_float_length
-           || (data.flags & SF_FL_BEFORE_EOL
-               && (!(data.flags & SF_FL_BEFORE_MEOL)
-                   || (RExC_flags & RXf_PMf_MULTILINE)))) 
-        {
-            I32 t,ml;
-
-           if (SvCUR(data.longest_fixed)  /* ok to leave SvCUR */
-               && data.offset_fixed == data.offset_float_min
-               && SvCUR(data.longest_fixed) == SvCUR(data.longest_float))
-                   goto remove_float;          /* As in (a)+. */
-
-            /* copy the information about the longest float from the reg_scan_data
-               over to the program. */
-           if (SvUTF8(data.longest_float)) {
-               r->float_utf8 = data.longest_float;
-               r->float_substr = NULL;
-           } else {
-               r->float_substr = data.longest_float;
-               r->float_utf8 = NULL;
-           }
-           /* float_end_shift is how many chars that must be matched that 
-              follow this item. We calculate it ahead of time as once the
-              lookbehind offset is added in we lose the ability to correctly
-              calculate it.*/
-           ml = data.minlen_float ? *(data.minlen_float) 
-                                  : (I32)longest_float_length;
-           r->float_end_shift = ml - data.offset_float_min
-               - longest_float_length + (SvTAIL(data.longest_float) != 0)
-               + data.lookbehind_float;
-           r->float_min_offset = data.offset_float_min - data.lookbehind_float;
-           r->float_max_offset = data.offset_float_max;
-           if (data.offset_float_max < I32_MAX) /* Don't offset infinity */
-               r->float_max_offset -= data.lookbehind_float;
-           
-           t = (data.flags & SF_FL_BEFORE_EOL /* Can't have SEOL and MULTI */
-                      && (!(data.flags & SF_FL_BEFORE_MEOL)
-                          || (RExC_flags & RXf_PMf_MULTILINE)));
-           fbm_compile(data.longest_float, t ? FBMcf_TAIL : 0);
-       }
-       else {
-         remove_float:
-           r->float_substr = r->float_utf8 = NULL;
-           SvREFCNT_dec(data.longest_float);
-           longest_float_length = 0;
-       }
-
-        /* Note that code very similar to this but for floating string 
-           is immediately above, changes may need to be made to both. 
-           Be careful. 
-         */
-       longest_fixed_length = CHR_SVLEN(data.longest_fixed);
-       if (longest_fixed_length
-           || (data.flags & SF_FIX_BEFORE_EOL /* Cannot have SEOL and MULTI */
-               && (!(data.flags & SF_FIX_BEFORE_MEOL)
-                   || (RExC_flags & RXf_PMf_MULTILINE)))) 
-        {
-            I32 t,ml;
-
-            /* copy the information about the longest fixed 
-               from the reg_scan_data over to the program. */
-           if (SvUTF8(data.longest_fixed)) {
-               r->anchored_utf8 = data.longest_fixed;
-               r->anchored_substr = NULL;
-           } else {
-               r->anchored_substr = data.longest_fixed;
-               r->anchored_utf8 = NULL;
-           }
-           /* fixed_end_shift is how many chars that must be matched that 
-              follow this item. We calculate it ahead of time as once the
-              lookbehind offset is added in we lose the ability to correctly
-              calculate it.*/
-            ml = data.minlen_fixed ? *(data.minlen_fixed) 
-                                   : (I32)longest_fixed_length;
-            r->anchored_end_shift = ml - data.offset_fixed
-               - longest_fixed_length + (SvTAIL(data.longest_fixed) != 0)
-               + data.lookbehind_fixed;
-           r->anchored_offset = data.offset_fixed - data.lookbehind_fixed;
-
-           t = (data.flags & SF_FIX_BEFORE_EOL /* Can't have SEOL and MULTI */
-                && (!(data.flags & SF_FIX_BEFORE_MEOL)
-                    || (RExC_flags & RXf_PMf_MULTILINE)));
-           fbm_compile(data.longest_fixed, t ? FBMcf_TAIL : 0);
-       }
-       else {
-           r->anchored_substr = r->anchored_utf8 = NULL;
-           SvREFCNT_dec(data.longest_fixed);
-           longest_fixed_length = 0;
-       }
-       if (ri->regstclass
-           && (OP(ri->regstclass) == REG_ANY || OP(ri->regstclass) == SANY))
-           ri->regstclass = NULL;
-
-       /* If the synthetic start class were to ever be used when EOS is set,
-        * that bit would have to be cleared, as it is shared with another */
-       if ((!(r->anchored_substr || r->anchored_utf8) || r->anchored_offset)
-           && stclass_flag
-           && !(data.start_class->flags & ANYOF_EOS)
-           && !cl_is_anything(data.start_class))
-       {
-           const U32 n = add_data(pRExC_state, 1, "f");
-
-           Newx(RExC_rxi->data->data[n], 1,
-               struct regnode_charclass_class);
-           StructCopy(data.start_class,
-                      (struct regnode_charclass_class*)RExC_rxi->data->data[n],
-                      struct regnode_charclass_class);
-           ri->regstclass = (regnode*)RExC_rxi->data->data[n];
-           r->intflags &= ~PREGf_SKIP; /* Used in find_byclass(). */
-           DEBUG_COMPILE_r({ SV *sv = sv_newmortal();
-                     regprop(r, sv, (regnode*)data.start_class);
-                     PerlIO_printf(Perl_debug_log,
-                                   "synthetic stclass \"%s\".\n",
-                                   SvPVX_const(sv));});
-       }
-
-       /* A temporary algorithm prefers floated substr to fixed one to dig more info. */
-       if (longest_fixed_length > longest_float_length) {
-           r->check_end_shift = r->anchored_end_shift;
-           r->check_substr = r->anchored_substr;
-           r->check_utf8 = r->anchored_utf8;
-           r->check_offset_min = r->check_offset_max = r->anchored_offset;
-           if (r->extflags & RXf_ANCH_SINGLE)
-               r->extflags |= RXf_NOSCAN;
-       }
-       else {
-           r->check_end_shift = r->float_end_shift;
-           r->check_substr = r->float_substr;
-           r->check_utf8 = r->float_utf8;
-           r->check_offset_min = r->float_min_offset;
-           r->check_offset_max = r->float_max_offset;
-       }
-       /* XXXX Currently intuiting is not compatible with ANCH_GPOS.
-          This should be changed ASAP!  */
-       if ((r->check_substr || r->check_utf8) && !(r->extflags & RXf_ANCH_GPOS)) {
-           r->extflags |= RXf_USE_INTUIT;
-           if (SvTAIL(r->check_substr ? r->check_substr : r->check_utf8))
-               r->extflags |= RXf_INTUIT_TAIL;
-       }
-       /* XXX Unneeded? dmq (shouldn't as this is handled elsewhere)
-       if ( (STRLEN)minlen < longest_float_length )
-            minlen= longest_float_length;
-        if ( (STRLEN)minlen < longest_fixed_length )
-            minlen= longest_fixed_length;     
-        */
-    }
-    else {
-       /* Several toplevels. Best we can is to set minlen. */
-       I32 fake;
-       struct regnode_charclass_class ch_class;
-       I32 last_close = 0;
-       
-       DEBUG_PARSE_r(PerlIO_printf(Perl_debug_log, "\nMulti Top Level\n"));
-
-       scan = ri->program + 1;
-       cl_init(pRExC_state, &ch_class);
-       data.start_class = &ch_class;
-       data.last_closep = &last_close;
-
-        
-       minlen = study_chunk(pRExC_state, &scan, &minlen, &fake, scan + RExC_size,
-           &data, -1, NULL, NULL, SCF_DO_STCLASS_AND|SCF_WHILEM_VISITED_POS,0);
-        
-        CHECK_RESTUDY_GOTO;
-
-       r->check_substr = r->check_utf8 = r->anchored_substr = r->anchored_utf8
-               = r->float_substr = r->float_utf8 = NULL;
-
-       /* If the synthetic start class were to ever be used when EOS is set,
-        * that bit would have to be cleared, as it is shared with another */
-       if (!(data.start_class->flags & ANYOF_EOS)
-           && !cl_is_anything(data.start_class))
-       {
-           const U32 n = add_data(pRExC_state, 1, "f");
-
-           Newx(RExC_rxi->data->data[n], 1,
-               struct regnode_charclass_class);
-           StructCopy(data.start_class,
-                      (struct regnode_charclass_class*)RExC_rxi->data->data[n],
-                      struct regnode_charclass_class);
-           ri->regstclass = (regnode*)RExC_rxi->data->data[n];
-           r->intflags &= ~PREGf_SKIP; /* Used in find_byclass(). */
-           DEBUG_COMPILE_r({ SV* sv = sv_newmortal();
-                     regprop(r, sv, (regnode*)data.start_class);
-                     PerlIO_printf(Perl_debug_log,
-                                   "synthetic stclass \"%s\".\n",
-                                   SvPVX_const(sv));});
-       }
-    }
-
-    /* Guard against an embedded (?=) or (?<=) with a longer minlen than
-       the "real" pattern. */
-    DEBUG_OPTIMISE_r({
-       PerlIO_printf(Perl_debug_log,"minlen: %"IVdf" r->minlen:%"IVdf"\n",
-                     (IV)minlen, (IV)r->minlen);
-    });
-    r->minlenret = minlen;
-    if (r->minlen < minlen) 
-        r->minlen = minlen;
-    
-    if (RExC_seen & REG_SEEN_GPOS)
-       r->extflags |= RXf_GPOS_SEEN;
-    if (RExC_seen & REG_SEEN_LOOKBEHIND)
-       r->extflags |= RXf_LOOKBEHIND_SEEN;
-    if (RExC_seen & REG_SEEN_EVAL)
-       r->extflags |= RXf_EVAL_SEEN;
-    if (RExC_seen & REG_SEEN_CANY)
-       r->extflags |= RXf_CANY_SEEN;
-    if (RExC_seen & REG_SEEN_VERBARG)
-       r->intflags |= PREGf_VERBARG_SEEN;
-    if (RExC_seen & REG_SEEN_CUTGROUP)
-       r->intflags |= PREGf_CUTGROUP_SEEN;
-    if (RExC_paren_names)
-        RXp_PAREN_NAMES(r) = MUTABLE_HV(SvREFCNT_inc(RExC_paren_names));
-    else
-        RXp_PAREN_NAMES(r) = NULL;
-
-#ifdef STUPID_PATTERN_CHECKS            
-    if (RX_PRELEN(rx) == 0)
-        r->extflags |= RXf_NULL;
-    if (r->extflags & RXf_SPLIT && RX_PRELEN(rx) == 1 && RX_PRECOMP(rx)[0] == ' ')
-        /* XXX: this should happen BEFORE we compile */
-        r->extflags |= (RXf_SKIPWHITE|RXf_WHITE); 
-    else if (RX_PRELEN(rx) == 3 && memEQ("\\s+", RX_PRECOMP(rx), 3))
-        r->extflags |= RXf_WHITE;
-    else if (RX_PRELEN(rx) == 1 && RXp_PRECOMP(rx)[0] == '^')
-        r->extflags |= RXf_START_ONLY;
-#else
-    if (r->extflags & RXf_SPLIT && RX_PRELEN(rx) == 1 && RX_PRECOMP(rx)[0] == ' ')
-            /* XXX: this should happen BEFORE we compile */
-            r->extflags |= (RXf_SKIPWHITE|RXf_WHITE); 
-    else {
-        regnode *first = ri->program + 1;
-        U8 fop = OP(first);
-        U8 nop = OP(NEXTOPER(first));
-        
-        if (PL_regkind[fop] == NOTHING && nop == END)
-            r->extflags |= RXf_NULL;
-        else if (PL_regkind[fop] == BOL && nop == END)
-            r->extflags |= RXf_START_ONLY;
-        else if (fop == PLUS && nop ==SPACE && OP(regnext(first))==END)
-            r->extflags |= RXf_WHITE;    
-    }
-#endif
-#ifdef DEBUGGING
-    if (RExC_paren_names) {
-        ri->name_list_idx = add_data( pRExC_state, 1, "a" );
-        ri->data->data[ri->name_list_idx] = (void*)SvREFCNT_inc(RExC_paren_name_list);
-    } else
-#endif
-        ri->name_list_idx = 0;
-
-    if (RExC_recurse_count) {
-        for ( ; RExC_recurse_count ; RExC_recurse_count-- ) {
-            const regnode *scan = RExC_recurse[RExC_recurse_count-1];
-            ARG2L_SET( scan, RExC_open_parens[ARG(scan)-1] - scan );
-        }
-    }
-    Newxz(r->offs, RExC_npar, regexp_paren_pair);
-    /* assume we don't need to swap parens around before we match */
-
-    DEBUG_DUMP_r({
-        PerlIO_printf(Perl_debug_log,"Final program:\n");
-        regdump(r);
-    });
-#ifdef RE_TRACK_PATTERN_OFFSETS
-    DEBUG_OFFSETS_r(if (ri->u.offsets) {
-        const U32 len = ri->u.offsets[0];
-        U32 i;
-        GET_RE_DEBUG_FLAGS_DECL;
-        PerlIO_printf(Perl_debug_log, "Offsets: [%"UVuf"]\n\t", (UV)ri->u.offsets[0]);
-        for (i = 1; i <= len; i++) {
-            if (ri->u.offsets[i*2-1] || ri->u.offsets[i*2])
-                PerlIO_printf(Perl_debug_log, "%"UVuf":%"UVuf"[%"UVuf"] ",
-                (UV)i, (UV)ri->u.offsets[i*2-1], (UV)ri->u.offsets[i*2]);
-            }
-        PerlIO_printf(Perl_debug_log, "\n");
-    });
-#endif
-    return rx;
-}
-
-#undef RE_ENGINE_PTR
-
-
-SV*
-Perl_reg_named_buff(pTHX_ REGEXP * const rx, SV * const key, SV * const value,
-                    const U32 flags)
-{
-    PERL_ARGS_ASSERT_REG_NAMED_BUFF;
-
-    PERL_UNUSED_ARG(value);
-
-    if (flags & RXapif_FETCH) {
-        return reg_named_buff_fetch(rx, key, flags);
-    } else if (flags & (RXapif_STORE | RXapif_DELETE | RXapif_CLEAR)) {
-        Perl_croak_no_modify(aTHX);
-        return NULL;
-    } else if (flags & RXapif_EXISTS) {
-        return reg_named_buff_exists(rx, key, flags)
-            ? &PL_sv_yes
-            : &PL_sv_no;
-    } else if (flags & RXapif_REGNAMES) {
-        return reg_named_buff_all(rx, flags);
-    } else if (flags & (RXapif_SCALAR | RXapif_REGNAMES_COUNT)) {
-        return reg_named_buff_scalar(rx, flags);
-    } else {
-        Perl_croak(aTHX_ "panic: Unknown flags %d in named_buff", (int)flags);
-        return NULL;
-    }
-}
-
-SV*
-Perl_reg_named_buff_iter(pTHX_ REGEXP * const rx, const SV * const lastkey,
-                         const U32 flags)
-{
-    PERL_ARGS_ASSERT_REG_NAMED_BUFF_ITER;
-    PERL_UNUSED_ARG(lastkey);
-
-    if (flags & RXapif_FIRSTKEY)
-        return reg_named_buff_firstkey(rx, flags);
-    else if (flags & RXapif_NEXTKEY)
-        return reg_named_buff_nextkey(rx, flags);
-    else {
-        Perl_croak(aTHX_ "panic: Unknown flags %d in named_buff_iter", (int)flags);
-        return NULL;
-    }
-}
-
-SV*
-Perl_reg_named_buff_fetch(pTHX_ REGEXP * const r, SV * const namesv,
-                         const U32 flags)
-{
-    AV *retarray = NULL;
-    SV *ret;
-    struct regexp *const rx = (struct regexp *)SvANY(r);
-
-    PERL_ARGS_ASSERT_REG_NAMED_BUFF_FETCH;
-
-    if (flags & RXapif_ALL)
-        retarray=newAV();
-
-    if (rx && RXp_PAREN_NAMES(rx)) {
-        HE *he_str = hv_fetch_ent( RXp_PAREN_NAMES(rx), namesv, 0, 0 );
-        if (he_str) {
-            IV i;
-            SV* sv_dat=HeVAL(he_str);
-            I32 *nums=(I32*)SvPVX(sv_dat);
-            for ( i=0; i<SvIVX(sv_dat); i++ ) {
-                if ((I32)(rx->nparens) >= nums[i]
-                    && rx->offs[nums[i]].start != -1
-                    && rx->offs[nums[i]].end != -1)
-                {
-                    ret = newSVpvs("");
-                    CALLREG_NUMBUF_FETCH(r,nums[i],ret);
-                    if (!retarray)
-                        return ret;
-                } else {
-                    ret = newSVsv(&PL_sv_undef);
-                }
-                if (retarray)
-                    av_push(retarray, ret);
-            }
-            if (retarray)
-                return newRV_noinc(MUTABLE_SV(retarray));
-        }
-    }
-    return NULL;
-}
-
-bool
-Perl_reg_named_buff_exists(pTHX_ REGEXP * const r, SV * const key,
-                           const U32 flags)
-{
-    struct regexp *const rx = (struct regexp *)SvANY(r);
-
-    PERL_ARGS_ASSERT_REG_NAMED_BUFF_EXISTS;
-
-    if (rx && RXp_PAREN_NAMES(rx)) {
-        if (flags & RXapif_ALL) {
-            return hv_exists_ent(RXp_PAREN_NAMES(rx), key, 0);
-        } else {
-           SV *sv = CALLREG_NAMED_BUFF_FETCH(r, key, flags);
-            if (sv) {
-               SvREFCNT_dec(sv);
-                return TRUE;
-            } else {
-                return FALSE;
-            }
-        }
-    } else {
-        return FALSE;
-    }
-}
-
-SV*
-Perl_reg_named_buff_firstkey(pTHX_ REGEXP * const r, const U32 flags)
-{
-    struct regexp *const rx = (struct regexp *)SvANY(r);
-
-    PERL_ARGS_ASSERT_REG_NAMED_BUFF_FIRSTKEY;
-
-    if ( rx && RXp_PAREN_NAMES(rx) ) {
-       (void)hv_iterinit(RXp_PAREN_NAMES(rx));
-
-       return CALLREG_NAMED_BUFF_NEXTKEY(r, NULL, flags & ~RXapif_FIRSTKEY);
-    } else {
-       return FALSE;
-    }
-}
-
-SV*
-Perl_reg_named_buff_nextkey(pTHX_ REGEXP * const r, const U32 flags)
-{
-    struct regexp *const rx = (struct regexp *)SvANY(r);
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_REG_NAMED_BUFF_NEXTKEY;
-
-    if (rx && RXp_PAREN_NAMES(rx)) {
-        HV *hv = RXp_PAREN_NAMES(rx);
-        HE *temphe;
-        while ( (temphe = hv_iternext_flags(hv,0)) ) {
-            IV i;
-            IV parno = 0;
-            SV* sv_dat = HeVAL(temphe);
-            I32 *nums = (I32*)SvPVX(sv_dat);
-            for ( i = 0; i < SvIVX(sv_dat); i++ ) {
-                if ((I32)(rx->lastparen) >= nums[i] &&
-                    rx->offs[nums[i]].start != -1 &&
-                    rx->offs[nums[i]].end != -1)
-                {
-                    parno = nums[i];
-                    break;
-                }
-            }
-            if (parno || flags & RXapif_ALL) {
-               return newSVhek(HeKEY_hek(temphe));
-            }
-        }
-    }
-    return NULL;
-}
-
-SV*
-Perl_reg_named_buff_scalar(pTHX_ REGEXP * const r, const U32 flags)
-{
-    SV *ret;
-    AV *av;
-    I32 length;
-    struct regexp *const rx = (struct regexp *)SvANY(r);
-
-    PERL_ARGS_ASSERT_REG_NAMED_BUFF_SCALAR;
-
-    if (rx && RXp_PAREN_NAMES(rx)) {
-        if (flags & (RXapif_ALL | RXapif_REGNAMES_COUNT)) {
-            return newSViv(HvTOTALKEYS(RXp_PAREN_NAMES(rx)));
-        } else if (flags & RXapif_ONE) {
-            ret = CALLREG_NAMED_BUFF_ALL(r, (flags | RXapif_REGNAMES));
-            av = MUTABLE_AV(SvRV(ret));
-            length = av_len(av);
-           SvREFCNT_dec(ret);
-            return newSViv(length + 1);
-        } else {
-            Perl_croak(aTHX_ "panic: Unknown flags %d in named_buff_scalar", (int)flags);
-            return NULL;
-        }
-    }
-    return &PL_sv_undef;
-}
-
-SV*
-Perl_reg_named_buff_all(pTHX_ REGEXP * const r, const U32 flags)
-{
-    struct regexp *const rx = (struct regexp *)SvANY(r);
-    AV *av = newAV();
-
-    PERL_ARGS_ASSERT_REG_NAMED_BUFF_ALL;
-
-    if (rx && RXp_PAREN_NAMES(rx)) {
-        HV *hv= RXp_PAREN_NAMES(rx);
-        HE *temphe;
-        (void)hv_iterinit(hv);
-        while ( (temphe = hv_iternext_flags(hv,0)) ) {
-            IV i;
-            IV parno = 0;
-            SV* sv_dat = HeVAL(temphe);
-            I32 *nums = (I32*)SvPVX(sv_dat);
-            for ( i = 0; i < SvIVX(sv_dat); i++ ) {
-                if ((I32)(rx->lastparen) >= nums[i] &&
-                    rx->offs[nums[i]].start != -1 &&
-                    rx->offs[nums[i]].end != -1)
-                {
-                    parno = nums[i];
-                    break;
-                }
-            }
-            if (parno || flags & RXapif_ALL) {
-                av_push(av, newSVhek(HeKEY_hek(temphe)));
-            }
-        }
-    }
-
-    return newRV_noinc(MUTABLE_SV(av));
-}
-
-void
-Perl_reg_numbered_buff_fetch(pTHX_ REGEXP * const r, const I32 paren,
-                            SV * const sv)
-{
-    struct regexp *const rx = (struct regexp *)SvANY(r);
-    char *s = NULL;
-    I32 i = 0;
-    I32 s1, t1;
-
-    PERL_ARGS_ASSERT_REG_NUMBERED_BUFF_FETCH;
-        
-    if (!rx->subbeg) {
-        sv_setsv(sv,&PL_sv_undef);
-        return;
-    } 
-    else               
-    if (paren == RX_BUFF_IDX_PREMATCH && rx->offs[0].start != -1) {
-        /* $` */
-       i = rx->offs[0].start;
-       s = rx->subbeg;
-    }
-    else 
-    if (paren == RX_BUFF_IDX_POSTMATCH && rx->offs[0].end != -1) {
-        /* $' */
-       s = rx->subbeg + rx->offs[0].end;
-       i = rx->sublen - rx->offs[0].end;
-    } 
-    else
-    if ( 0 <= paren && paren <= (I32)rx->nparens &&
-        (s1 = rx->offs[paren].start) != -1 &&
-        (t1 = rx->offs[paren].end) != -1)
-    {
-        /* $& $1 ... */
-        i = t1 - s1;
-        s = rx->subbeg + s1;
-    } else {
-        sv_setsv(sv,&PL_sv_undef);
-        return;
-    }          
-    assert(rx->sublen >= (s - rx->subbeg) + i );
-    if (i >= 0) {
-        const int oldtainted = PL_tainted;
-        TAINT_NOT;
-        sv_setpvn(sv, s, i);
-        PL_tainted = oldtainted;
-        if ( (rx->extflags & RXf_CANY_SEEN)
-            ? (RXp_MATCH_UTF8(rx)
-                        && (!i || is_utf8_string((U8*)s, i)))
-            : (RXp_MATCH_UTF8(rx)) )
-        {
-            SvUTF8_on(sv);
-        }
-        else
-            SvUTF8_off(sv);
-        if (PL_tainting) {
-            if (RXp_MATCH_TAINTED(rx)) {
-                if (SvTYPE(sv) >= SVt_PVMG) {
-                    MAGIC* const mg = SvMAGIC(sv);
-                    MAGIC* mgt;
-                    PL_tainted = 1;
-                    SvMAGIC_set(sv, mg->mg_moremagic);
-                    SvTAINT(sv);
-                    if ((mgt = SvMAGIC(sv))) {
-                        mg->mg_moremagic = mgt;
-                        SvMAGIC_set(sv, mg);
-                    }
-                } else {
-                    PL_tainted = 1;
-                    SvTAINT(sv);
-                }
-            } else 
-                SvTAINTED_off(sv);
-        }
-    } else {
-        sv_setsv(sv,&PL_sv_undef);
-        return;
-    }
-}
-
-void
-Perl_reg_numbered_buff_store(pTHX_ REGEXP * const rx, const I32 paren,
-                                                        SV const * const value)
-{
-    PERL_ARGS_ASSERT_REG_NUMBERED_BUFF_STORE;
-
-    PERL_UNUSED_ARG(rx);
-    PERL_UNUSED_ARG(paren);
-    PERL_UNUSED_ARG(value);
-
-    if (!PL_localizing)
-        Perl_croak_no_modify(aTHX);
-}
-
-I32
-Perl_reg_numbered_buff_length(pTHX_ REGEXP * const r, const SV * const sv,
-                              const I32 paren)
-{
-    struct regexp *const rx = (struct regexp *)SvANY(r);
-    I32 i;
-    I32 s1, t1;
-
-    PERL_ARGS_ASSERT_REG_NUMBERED_BUFF_LENGTH;
-
-    /* Some of this code was originally in C<Perl_magic_len> in F<mg.c> */
-       switch (paren) {
-      /* $` / ${^PREMATCH} */
-      case RX_BUFF_IDX_PREMATCH:
-        if (rx->offs[0].start != -1) {
-                       i = rx->offs[0].start;
-                       if (i > 0) {
-                               s1 = 0;
-                               t1 = i;
-                               goto getlen;
-                       }
-           }
-        return 0;
-      /* $' / ${^POSTMATCH} */
-      case RX_BUFF_IDX_POSTMATCH:
-           if (rx->offs[0].end != -1) {
-                       i = rx->sublen - rx->offs[0].end;
-                       if (i > 0) {
-                               s1 = rx->offs[0].end;
-                               t1 = rx->sublen;
-                               goto getlen;
-                       }
-           }
-        return 0;
-      /* $& / ${^MATCH}, $1, $2, ... */
-      default:
-           if (paren <= (I32)rx->nparens &&
-            (s1 = rx->offs[paren].start) != -1 &&
-            (t1 = rx->offs[paren].end) != -1)
-           {
-            i = t1 - s1;
-            goto getlen;
-        } else {
-            if (ckWARN(WARN_UNINITIALIZED))
-                report_uninit((const SV *)sv);
-            return 0;
-        }
-    }
-  getlen:
-    if (i > 0 && RXp_MATCH_UTF8(rx)) {
-        const char * const s = rx->subbeg + s1;
-        const U8 *ep;
-        STRLEN el;
-
-        i = t1 - s1;
-        if (is_utf8_string_loclen((U8*)s, i, &ep, &el))
-                       i = el;
-    }
-    return i;
-}
-
-SV*
-Perl_reg_qr_package(pTHX_ REGEXP * const rx)
-{
-    PERL_ARGS_ASSERT_REG_QR_PACKAGE;
-       PERL_UNUSED_ARG(rx);
-       if (0)
-           return NULL;
-       else
-           return newSVpvs("Regexp");
-}
-
-/* Scans the name of a named buffer from the pattern.
- * If flags is REG_RSN_RETURN_NULL returns null.
- * If flags is REG_RSN_RETURN_NAME returns an SV* containing the name
- * If flags is REG_RSN_RETURN_DATA returns the data SV* corresponding
- * to the parsed name as looked up in the RExC_paren_names hash.
- * If there is an error throws a vFAIL().. type exception.
- */
-
-#define REG_RSN_RETURN_NULL    0
-#define REG_RSN_RETURN_NAME    1
-#define REG_RSN_RETURN_DATA    2
-
-STATIC SV*
-S_reg_scan_name(pTHX_ RExC_state_t *pRExC_state, U32 flags)
-{
-    char *name_start = RExC_parse;
-
-    PERL_ARGS_ASSERT_REG_SCAN_NAME;
-
-    if (isIDFIRST_lazy_if(RExC_parse, UTF)) {
-        /* skip IDFIRST by using do...while */
-       if (UTF)
-           do {
-               RExC_parse += UTF8SKIP(RExC_parse);
-           } while (isALNUM_utf8((U8*)RExC_parse));
-       else
-           do {
-               RExC_parse++;
-           } while (isALNUM(*RExC_parse));
-    }
-
-    if ( flags ) {
-        SV* sv_name
-           = newSVpvn_flags(name_start, (int)(RExC_parse - name_start),
-                            SVs_TEMP | (UTF ? SVf_UTF8 : 0));
-        if ( flags == REG_RSN_RETURN_NAME)
-            return sv_name;
-        else if (flags==REG_RSN_RETURN_DATA) {
-            HE *he_str = NULL;
-            SV *sv_dat = NULL;
-            if ( ! sv_name )      /* should not happen*/
-                Perl_croak(aTHX_ "panic: no svname in reg_scan_name");
-            if (RExC_paren_names)
-                he_str = hv_fetch_ent( RExC_paren_names, sv_name, 0, 0 );
-            if ( he_str )
-                sv_dat = HeVAL(he_str);
-            if ( ! sv_dat )
-                vFAIL("Reference to nonexistent named group");
-            return sv_dat;
-        }
-        else {
-            Perl_croak(aTHX_ "panic: bad flag in reg_scan_name");
-        }
-        /* NOT REACHED */
-    }
-    return NULL;
-}
-
-#define DEBUG_PARSE_MSG(funcname)     DEBUG_PARSE_r({           \
-    int rem=(int)(RExC_end - RExC_parse);                       \
-    int cut;                                                    \
-    int num;                                                    \
-    int iscut=0;                                                \
-    if (rem>10) {                                               \
-        rem=10;                                                 \
-        iscut=1;                                                \
-    }                                                           \
-    cut=10-rem;                                                 \
-    if (RExC_lastparse!=RExC_parse)                             \
-        PerlIO_printf(Perl_debug_log," >%.*s%-*s",              \
-            rem, RExC_parse,                                    \
-            cut + 4,                                            \
-            iscut ? "..." : "<"                                 \
-        );                                                      \
-    else                                                        \
-        PerlIO_printf(Perl_debug_log,"%16s","");                \
-                                                                \
-    if (SIZE_ONLY)                                              \
-       num = RExC_size + 1;                                     \
-    else                                                        \
-       num=REG_NODE_NUM(RExC_emit);                             \
-    if (RExC_lastnum!=num)                                      \
-       PerlIO_printf(Perl_debug_log,"|%4d",num);                \
-    else                                                        \
-       PerlIO_printf(Perl_debug_log,"|%4s","");                 \
-    PerlIO_printf(Perl_debug_log,"|%*s%-4s",                    \
-        (int)((depth*2)), "",                                   \
-        (funcname)                                              \
-    );                                                          \
-    RExC_lastnum=num;                                           \
-    RExC_lastparse=RExC_parse;                                  \
-})
-
-
-
-#define DEBUG_PARSE(funcname)     DEBUG_PARSE_r({           \
-    DEBUG_PARSE_MSG((funcname));                            \
-    PerlIO_printf(Perl_debug_log,"%4s","\n");               \
-})
-#define DEBUG_PARSE_FMT(funcname,fmt,args)     DEBUG_PARSE_r({           \
-    DEBUG_PARSE_MSG((funcname));                            \
-    PerlIO_printf(Perl_debug_log,fmt "\n",args);               \
-})
-/*
- - reg - regular expression, i.e. main body or parenthesized thing
- *
- * Caller must absorb opening parenthesis.
- *
- * Combining parenthesis handling with the base level of regular expression
- * is a trifle forced, but the need to tie the tails of the branches to what
- * follows makes it hard to avoid.
- */
-#define REGTAIL(x,y,z) regtail((x),(y),(z),depth+1)
-#ifdef DEBUGGING
-#define REGTAIL_STUDY(x,y,z) regtail_study((x),(y),(z),depth+1)
-#else
-#define REGTAIL_STUDY(x,y,z) regtail((x),(y),(z),depth+1)
-#endif
-
-STATIC regnode *
-S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp,U32 depth)
-    /* paren: Parenthesized? 0=top, 1=(, inside: changed to letter. */
-{
-    dVAR;
-    register regnode *ret;             /* Will be the head of the group. */
-    register regnode *br;
-    register regnode *lastbr;
-    register regnode *ender = NULL;
-    register I32 parno = 0;
-    I32 flags;
-    U32 oregflags = RExC_flags;
-    bool have_branch = 0;
-    bool is_open = 0;
-    I32 freeze_paren = 0;
-    I32 after_freeze = 0;
-
-    /* for (?g), (?gc), and (?o) warnings; warning
-       about (?c) will warn about (?g) -- japhy    */
-
-#define WASTED_O  0x01
-#define WASTED_G  0x02
-#define WASTED_C  0x04
-#define WASTED_GC (0x02|0x04)
-    I32 wastedflags = 0x00;
-
-    char * parse_start = RExC_parse; /* MJD */
-    char * const oregcomp_parse = RExC_parse;
-
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_REG;
-    DEBUG_PARSE("reg ");
-
-    *flagp = 0;                                /* Tentatively. */
-
-
-    /* Make an OPEN node, if parenthesized. */
-    if (paren) {
-        if ( *RExC_parse == '*') { /* (*VERB:ARG) */
-           char *start_verb = RExC_parse;
-           STRLEN verb_len = 0;
-           char *start_arg = NULL;
-           unsigned char op = 0;
-           int argok = 1;
-           int internal_argval = 0; /* internal_argval is only useful if !argok */
-           while ( *RExC_parse && *RExC_parse != ')' ) {
-               if ( *RExC_parse == ':' ) {
-                   start_arg = RExC_parse + 1;
-                   break;
-               }
-               RExC_parse++;
-           }
-           ++start_verb;
-           verb_len = RExC_parse - start_verb;
-           if ( start_arg ) {
-               RExC_parse++;
-               while ( *RExC_parse && *RExC_parse != ')' ) 
-                   RExC_parse++;
-               if ( *RExC_parse != ')' ) 
-                   vFAIL("Unterminated verb pattern argument");
-               if ( RExC_parse == start_arg )
-                   start_arg = NULL;
-           } else {
-               if ( *RExC_parse != ')' )
-                   vFAIL("Unterminated verb pattern");
-           }
-           
-           switch ( *start_verb ) {
-            case 'A':  /* (*ACCEPT) */
-                if ( memEQs(start_verb,verb_len,"ACCEPT") ) {
-                   op = ACCEPT;
-                   internal_argval = RExC_nestroot;
-               }
-               break;
-            case 'C':  /* (*COMMIT) */
-                if ( memEQs(start_verb,verb_len,"COMMIT") )
-                    op = COMMIT;
-                break;
-            case 'F':  /* (*FAIL) */
-                if ( verb_len==1 || memEQs(start_verb,verb_len,"FAIL") ) {
-                   op = OPFAIL;
-                   argok = 0;
-               }
-               break;
-            case ':':  /* (*:NAME) */
-           case 'M':  /* (*MARK:NAME) */
-               if ( verb_len==0 || memEQs(start_verb,verb_len,"MARK") ) {
-                    op = MARKPOINT;
-                    argok = -1;
-                }
-                break;
-            case 'P':  /* (*PRUNE) */
-                if ( memEQs(start_verb,verb_len,"PRUNE") )
-                    op = PRUNE;
-                break;
-            case 'S':   /* (*SKIP) */  
-                if ( memEQs(start_verb,verb_len,"SKIP") ) 
-                    op = SKIP;
-                break;
-            case 'T':  /* (*THEN) */
-                /* [19:06] <TimToady> :: is then */
-                if ( memEQs(start_verb,verb_len,"THEN") ) {
-                    op = CUTGROUP;
-                    RExC_seen |= REG_SEEN_CUTGROUP;
-                }
-                break;
-           }
-           if ( ! op ) {
-               RExC_parse++;
-               vFAIL3("Unknown verb pattern '%.*s'",
-                   verb_len, start_verb);
-           }
-           if ( argok ) {
-                if ( start_arg && internal_argval ) {
-                   vFAIL3("Verb pattern '%.*s' may not have an argument",
-                       verb_len, start_verb); 
-               } else if ( argok < 0 && !start_arg ) {
-                    vFAIL3("Verb pattern '%.*s' has a mandatory argument",
-                       verb_len, start_verb);    
-               } else {
-                   ret = reganode(pRExC_state, op, internal_argval);
-                   if ( ! internal_argval && ! SIZE_ONLY ) {
-                        if (start_arg) {
-                            SV *sv = newSVpvn( start_arg, RExC_parse - start_arg);
-                            ARG(ret) = add_data( pRExC_state, 1, "S" );
-                            RExC_rxi->data->data[ARG(ret)]=(void*)sv;
-                            ret->flags = 0;
-                        } else {
-                            ret->flags = 1; 
-                        }
-                    }              
-               }
-               if (!internal_argval)
-                   RExC_seen |= REG_SEEN_VERBARG;
-           } else if ( start_arg ) {
-               vFAIL3("Verb pattern '%.*s' may not have an argument",
-                       verb_len, start_verb);    
-           } else {
-               ret = reg_node(pRExC_state, op);
-           }
-           nextchar(pRExC_state);
-           return ret;
-        } else 
-       if (*RExC_parse == '?') { /* (?...) */
-           bool is_logical = 0;
-           const char * const seqstart = RExC_parse;
-            bool has_use_defaults = FALSE;
-
-           RExC_parse++;
-           paren = *RExC_parse++;
-           ret = NULL;                 /* For look-ahead/behind. */
-           switch (paren) {
-
-           case 'P':   /* (?P...) variants for those used to PCRE/Python */
-               paren = *RExC_parse++;
-               if ( paren == '<')         /* (?P<...>) named capture */
-                   goto named_capture;
-                else if (paren == '>') {   /* (?P>name) named recursion */
-                    goto named_recursion;
-                }
-                else if (paren == '=') {   /* (?P=...)  named backref */
-                    /* this pretty much dupes the code for \k<NAME> in regatom(), if
-                       you change this make sure you change that */
-                    char* name_start = RExC_parse;
-                   U32 num = 0;
-                    SV *sv_dat = reg_scan_name(pRExC_state,
-                        SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
-                    if (RExC_parse == name_start || *RExC_parse != ')')
-                        vFAIL2("Sequence %.3s... not terminated",parse_start);
-
-                    if (!SIZE_ONLY) {
-                        num = add_data( pRExC_state, 1, "S" );
-                        RExC_rxi->data->data[num]=(void*)sv_dat;
-                        SvREFCNT_inc_simple_void(sv_dat);
-                    }
-                    RExC_sawback = 1;
-                   ret = reganode(pRExC_state,
-                                  ((! FOLD)
-                                    ? NREF
-                                    : (UNI_SEMANTICS)
-                                      ? NREFFU
-                                      : (LOC)
-                                        ? NREFFL
-                                        : NREFF),
-                                   num);
-                    *flagp |= HASWIDTH;
-
-                    Set_Node_Offset(ret, parse_start+1);
-                    Set_Node_Cur_Length(ret); /* MJD */
-
-                    nextchar(pRExC_state);
-                    return ret;
-                }
-                RExC_parse++;
-               vFAIL3("Sequence (%.*s...) not recognized", RExC_parse-seqstart, seqstart);
-               /*NOTREACHED*/
-            case '<':           /* (?<...) */
-               if (*RExC_parse == '!')
-                   paren = ',';
-               else if (*RExC_parse != '=') 
-              named_capture:
-               {               /* (?<...>) */
-                   char *name_start;
-                   SV *svname;
-                   paren= '>';
-            case '\'':          /* (?'...') */
-                   name_start= RExC_parse;
-                   svname = reg_scan_name(pRExC_state,
-                       SIZE_ONLY ?  /* reverse test from the others */
-                       REG_RSN_RETURN_NAME : 
-                       REG_RSN_RETURN_NULL);
-                   if (RExC_parse == name_start) {
-                       RExC_parse++;
-                       vFAIL3("Sequence (%.*s...) not recognized", RExC_parse-seqstart, seqstart);
-                       /*NOTREACHED*/
-                    }
-                   if (*RExC_parse != paren)
-                       vFAIL2("Sequence (?%c... not terminated",
-                           paren=='>' ? '<' : paren);
-                   if (SIZE_ONLY) {
-                       HE *he_str;
-                       SV *sv_dat = NULL;
-                        if (!svname) /* shouldn't happen */
-                            Perl_croak(aTHX_
-                                "panic: reg_scan_name returned NULL");
-                        if (!RExC_paren_names) {
-                            RExC_paren_names= newHV();
-                            sv_2mortal(MUTABLE_SV(RExC_paren_names));
-#ifdef DEBUGGING
-                            RExC_paren_name_list= newAV();
-                            sv_2mortal(MUTABLE_SV(RExC_paren_name_list));
-#endif
-                        }
-                        he_str = hv_fetch_ent( RExC_paren_names, svname, 1, 0 );
-                        if ( he_str )
-                            sv_dat = HeVAL(he_str);
-                        if ( ! sv_dat ) {
-                            /* croak baby croak */
-                            Perl_croak(aTHX_
-                                "panic: paren_name hash element allocation failed");
-                        } else if ( SvPOK(sv_dat) ) {
-                            /* (?|...) can mean we have dupes so scan to check
-                               its already been stored. Maybe a flag indicating
-                               we are inside such a construct would be useful,
-                               but the arrays are likely to be quite small, so
-                               for now we punt -- dmq */
-                            IV count = SvIV(sv_dat);
-                            I32 *pv = (I32*)SvPVX(sv_dat);
-                            IV i;
-                            for ( i = 0 ; i < count ; i++ ) {
-                                if ( pv[i] == RExC_npar ) {
-                                    count = 0;
-                                    break;
-                                }
-                            }
-                            if ( count ) {
-                                pv = (I32*)SvGROW(sv_dat, SvCUR(sv_dat) + sizeof(I32)+1);
-                                SvCUR_set(sv_dat, SvCUR(sv_dat) + sizeof(I32));
-                                pv[count] = RExC_npar;
-                                SvIV_set(sv_dat, SvIVX(sv_dat) + 1);
-                            }
-                        } else {
-                            (void)SvUPGRADE(sv_dat,SVt_PVNV);
-                            sv_setpvn(sv_dat, (char *)&(RExC_npar), sizeof(I32));
-                            SvIOK_on(sv_dat);
-                            SvIV_set(sv_dat, 1);
-                        }
-#ifdef DEBUGGING
-                        if (!av_store(RExC_paren_name_list, RExC_npar, SvREFCNT_inc(svname)))
-                            SvREFCNT_dec(svname);
-#endif
-
-                        /*sv_dump(sv_dat);*/
-                    }
-                    nextchar(pRExC_state);
-                   paren = 1;
-                   goto capturing_parens;
-               }
-                RExC_seen |= REG_SEEN_LOOKBEHIND;
-               RExC_in_lookbehind++;
-               RExC_parse++;
-           case '=':           /* (?=...) */
-               RExC_seen_zerolen++;
-                break;
-           case '!':           /* (?!...) */
-               RExC_seen_zerolen++;
-               if (*RExC_parse == ')') {
-                   ret=reg_node(pRExC_state, OPFAIL);
-                   nextchar(pRExC_state);
-                   return ret;
-               }
-               break;
-           case '|':           /* (?|...) */
-               /* branch reset, behave like a (?:...) except that
-                  buffers in alternations share the same numbers */
-               paren = ':'; 
-               after_freeze = freeze_paren = RExC_npar;
-               break;
-           case ':':           /* (?:...) */
-           case '>':           /* (?>...) */
-               break;
-           case '$':           /* (?$...) */
-           case '@':           /* (?@...) */
-               vFAIL2("Sequence (?%c...) not implemented", (int)paren);
-               break;
-           case '#':           /* (?#...) */
-               while (*RExC_parse && *RExC_parse != ')')
-                   RExC_parse++;
-               if (*RExC_parse != ')')
-                   FAIL("Sequence (?#... not terminated");
-               nextchar(pRExC_state);
-               *flagp = TRYAGAIN;
-               return NULL;
-           case '0' :           /* (?0) */
-           case 'R' :           /* (?R) */
-               if (*RExC_parse != ')')
-                   FAIL("Sequence (?R) not terminated");
-               ret = reg_node(pRExC_state, GOSTART);
-               *flagp |= POSTPONED;
-               nextchar(pRExC_state);
-               return ret;
-               /*notreached*/
-            { /* named and numeric backreferences */
-                I32 num;
-            case '&':            /* (?&NAME) */
-                parse_start = RExC_parse - 1;
-              named_recursion:
-                {
-                   SV *sv_dat = reg_scan_name(pRExC_state,
-                       SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
-                    num = sv_dat ? *((I32 *)SvPVX(sv_dat)) : 0;
-                }
-                goto gen_recurse_regop;
-                /* NOT REACHED */
-            case '+':
-                if (!(RExC_parse[0] >= '1' && RExC_parse[0] <= '9')) {
-                    RExC_parse++;
-                    vFAIL("Illegal pattern");
-                }
-                goto parse_recursion;
-                /* NOT REACHED*/
-            case '-': /* (?-1) */
-                if (!(RExC_parse[0] >= '1' && RExC_parse[0] <= '9')) {
-                    RExC_parse--; /* rewind to let it be handled later */
-                    goto parse_flags;
-                } 
-                /*FALLTHROUGH */
-            case '1': case '2': case '3': case '4': /* (?1) */
-           case '5': case '6': case '7': case '8': case '9':
-               RExC_parse--;
-              parse_recursion:
-               num = atoi(RExC_parse);
-               parse_start = RExC_parse - 1; /* MJD */
-               if (*RExC_parse == '-')
-                   RExC_parse++;
-               while (isDIGIT(*RExC_parse))
-                       RExC_parse++;
-               if (*RExC_parse!=')') 
-                   vFAIL("Expecting close bracket");
-                       
-              gen_recurse_regop:
-                if ( paren == '-' ) {
-                    /*
-                    Diagram of capture buffer numbering.
-                    Top line is the normal capture buffer numbers
-                    Bottom line is the negative indexing as from
-                    the X (the (?-2))
-
-                    +   1 2    3 4 5 X          6 7
-                       /(a(x)y)(a(b(c(?-2)d)e)f)(g(h))/
-                    -   5 4    3 2 1 X          x x
-
-                    */
-                    num = RExC_npar + num;
-                    if (num < 1)  {
-                        RExC_parse++;
-                        vFAIL("Reference to nonexistent group");
-                    }
-                } else if ( paren == '+' ) {
-                    num = RExC_npar + num - 1;
-                }
-
-                ret = reganode(pRExC_state, GOSUB, num);
-                if (!SIZE_ONLY) {
-                   if (num > (I32)RExC_rx->nparens) {
-                       RExC_parse++;
-                       vFAIL("Reference to nonexistent group");
-                   }
-                   ARG2L_SET( ret, RExC_recurse_count++);
-                    RExC_emit++;
-                   DEBUG_OPTIMISE_MORE_r(PerlIO_printf(Perl_debug_log,
-                       "Recurse #%"UVuf" to %"IVdf"\n", (UV)ARG(ret), (IV)ARG2L(ret)));
-               } else {
-                   RExC_size++;
-               }
-               RExC_seen |= REG_SEEN_RECURSE;
-                Set_Node_Length(ret, 1 + regarglen[OP(ret)]); /* MJD */
-               Set_Node_Offset(ret, parse_start); /* MJD */
-
-                *flagp |= POSTPONED;
-                nextchar(pRExC_state);
-                return ret;
-            } /* named and numeric backreferences */
-            /* NOT REACHED */
-
-           case '?':           /* (??...) */
-               is_logical = 1;
-               if (*RExC_parse != '{') {
-                   RExC_parse++;
-                   vFAIL3("Sequence (%.*s...) not recognized", RExC_parse-seqstart, seqstart);
-                   /*NOTREACHED*/
-               }
-               *flagp |= POSTPONED;
-               paren = *RExC_parse++;
-               /* FALL THROUGH */
-           case '{':           /* (?{...}) */
-           {
-               I32 count = 1;
-               U32 n = 0;
-               char c;
-               char *s = RExC_parse;
-
-               RExC_seen_zerolen++;
-               RExC_seen |= REG_SEEN_EVAL;
-               while (count && (c = *RExC_parse)) {
-                   if (c == '\\') {
-                       if (RExC_parse[1])
-                           RExC_parse++;
-                   }
-                   else if (c == '{')
-                       count++;
-                   else if (c == '}')
-                       count--;
-                   RExC_parse++;
-               }
-               if (*RExC_parse != ')') {
-                   RExC_parse = s;             
-                   vFAIL("Sequence (?{...}) not terminated or not {}-balanced");
-               }
-               if (!SIZE_ONLY) {
-                   PAD *pad;
-                   OP_4tree *sop, *rop;
-                   SV * const sv = newSVpvn(s, RExC_parse - 1 - s);
-
-                   ENTER;
-                   Perl_save_re_context(aTHX);
-                   rop = Perl_sv_compile_2op_is_broken(aTHX_ sv, &sop, "re", &pad);
-                   sop->op_private |= OPpREFCOUNTED;
-                   /* re_dup will OpREFCNT_inc */
-                   OpREFCNT_set(sop, 1);
-                   LEAVE;
-
-                   n = add_data(pRExC_state, 3, "nop");
-                   RExC_rxi->data->data[n] = (void*)rop;
-                   RExC_rxi->data->data[n+1] = (void*)sop;
-                   RExC_rxi->data->data[n+2] = (void*)pad;
-                   SvREFCNT_dec(sv);
-               }
-               else {                                          /* First pass */
-                   if (PL_reginterp_cnt < ++RExC_seen_evals
-                       && IN_PERL_RUNTIME)
-                       /* No compiled RE interpolated, has runtime
-                          components ===> unsafe.  */
-                       FAIL("Eval-group not allowed at runtime, use re 'eval'");
-                   if (PL_tainting && PL_tainted)
-                       FAIL("Eval-group in insecure regular expression");
-#if PERL_VERSION > 8
-                   if (IN_PERL_COMPILETIME)
-                       PL_cv_has_eval = 1;
-#endif
-               }
-
-               nextchar(pRExC_state);
-               if (is_logical) {
-                   ret = reg_node(pRExC_state, LOGICAL);
-                   if (!SIZE_ONLY)
-                       ret->flags = 2;
-                    REGTAIL(pRExC_state, ret, reganode(pRExC_state, EVAL, n));
-                    /* deal with the length of this later - MJD */
-                   return ret;
-               }
-               ret = reganode(pRExC_state, EVAL, n);
-               Set_Node_Length(ret, RExC_parse - parse_start + 1);
-               Set_Node_Offset(ret, parse_start);
-               return ret;
-           }
-           case '(':           /* (?(?{...})...) and (?(?=...)...) */
-           {
-               int is_define= 0;
-               if (RExC_parse[0] == '?') {        /* (?(?...)) */
-                   if (RExC_parse[1] == '=' || RExC_parse[1] == '!'
-                       || RExC_parse[1] == '<'
-                       || RExC_parse[1] == '{') { /* Lookahead or eval. */
-                       I32 flag;
-                       
-                       ret = reg_node(pRExC_state, LOGICAL);
-                       if (!SIZE_ONLY)
-                           ret->flags = 1;
-                        REGTAIL(pRExC_state, ret, reg(pRExC_state, 1, &flag,depth+1));
-                       goto insert_if;
-                   }
-               }
-               else if ( RExC_parse[0] == '<'     /* (?(<NAME>)...) */
-                        || RExC_parse[0] == '\'' ) /* (?('NAME')...) */
-               {
-                   char ch = RExC_parse[0] == '<' ? '>' : '\'';
-                   char *name_start= RExC_parse++;
-                   U32 num = 0;
-                   SV *sv_dat=reg_scan_name(pRExC_state,
-                       SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
-                   if (RExC_parse == name_start || *RExC_parse != ch)
-                        vFAIL2("Sequence (?(%c... not terminated",
-                            (ch == '>' ? '<' : ch));
-                    RExC_parse++;
-                   if (!SIZE_ONLY) {
-                        num = add_data( pRExC_state, 1, "S" );
-                        RExC_rxi->data->data[num]=(void*)sv_dat;
-                        SvREFCNT_inc_simple_void(sv_dat);
-                    }
-                    ret = reganode(pRExC_state,NGROUPP,num);
-                    goto insert_if_check_paren;
-               }
-               else if (RExC_parse[0] == 'D' &&
-                        RExC_parse[1] == 'E' &&
-                        RExC_parse[2] == 'F' &&
-                        RExC_parse[3] == 'I' &&
-                        RExC_parse[4] == 'N' &&
-                        RExC_parse[5] == 'E')
-               {
-                   ret = reganode(pRExC_state,DEFINEP,0);
-                   RExC_parse +=6 ;
-                   is_define = 1;
-                   goto insert_if_check_paren;
-               }
-               else if (RExC_parse[0] == 'R') {
-                   RExC_parse++;
-                   parno = 0;
-                   if (RExC_parse[0] >= '1' && RExC_parse[0] <= '9' ) {
-                       parno = atoi(RExC_parse++);
-                       while (isDIGIT(*RExC_parse))
-                           RExC_parse++;
-                   } else if (RExC_parse[0] == '&') {
-                       SV *sv_dat;
-                       RExC_parse++;
-                       sv_dat = reg_scan_name(pRExC_state,
-                           SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
-                       parno = sv_dat ? *((I32 *)SvPVX(sv_dat)) : 0;
-                   }
-                   ret = reganode(pRExC_state,INSUBP,parno); 
-                   goto insert_if_check_paren;
-               }
-               else if (RExC_parse[0] >= '1' && RExC_parse[0] <= '9' ) {
-                    /* (?(1)...) */
-                   char c;
-                   parno = atoi(RExC_parse++);
-
-                   while (isDIGIT(*RExC_parse))
-                       RExC_parse++;
-                    ret = reganode(pRExC_state, GROUPP, parno);
-
-                 insert_if_check_paren:
-                   if ((c = *nextchar(pRExC_state)) != ')')
-                       vFAIL("Switch condition not recognized");
-                 insert_if:
-                    REGTAIL(pRExC_state, ret, reganode(pRExC_state, IFTHEN, 0));
-                    br = regbranch(pRExC_state, &flags, 1,depth+1);
-                   if (br == NULL)
-                       br = reganode(pRExC_state, LONGJMP, 0);
-                   else
-                        REGTAIL(pRExC_state, br, reganode(pRExC_state, LONGJMP, 0));
-                   c = *nextchar(pRExC_state);
-                   if (flags&HASWIDTH)
-                       *flagp |= HASWIDTH;
-                   if (c == '|') {
-                       if (is_define) 
-                           vFAIL("(?(DEFINE)....) does not allow branches");
-                       lastbr = reganode(pRExC_state, IFTHEN, 0); /* Fake one for optimizer. */
-                        regbranch(pRExC_state, &flags, 1,depth+1);
-                        REGTAIL(pRExC_state, ret, lastbr);
-                       if (flags&HASWIDTH)
-                           *flagp |= HASWIDTH;
-                       c = *nextchar(pRExC_state);
-                   }
-                   else
-                       lastbr = NULL;
-                   if (c != ')')
-                       vFAIL("Switch (?(condition)... contains too many branches");
-                   ender = reg_node(pRExC_state, TAIL);
-                    REGTAIL(pRExC_state, br, ender);
-                   if (lastbr) {
-                        REGTAIL(pRExC_state, lastbr, ender);
-                        REGTAIL(pRExC_state, NEXTOPER(NEXTOPER(lastbr)), ender);
-                   }
-                   else
-                        REGTAIL(pRExC_state, ret, ender);
-                    RExC_size++; /* XXX WHY do we need this?!!
-                                    For large programs it seems to be required
-                                    but I can't figure out why. -- dmq*/
-                   return ret;
-               }
-               else {
-                   vFAIL2("Unknown switch condition (?(%.2s", RExC_parse);
-               }
-           }
-            case 0:
-               RExC_parse--; /* for vFAIL to print correctly */
-                vFAIL("Sequence (? incomplete");
-                break;
-            case DEFAULT_PAT_MOD:   /* Use default flags with the exceptions
-                                      that follow */
-                has_use_defaults = TRUE;
-                STD_PMMOD_FLAGS_CLEAR(&RExC_flags);
-               if (RExC_utf8) {    /* But the default for a utf8 pattern is
-                                      unicode semantics */
-                   set_regex_charset(&RExC_flags, REGEX_UNICODE_CHARSET);
-               }
-                goto parse_flags;
-           default:
-               --RExC_parse;
-               parse_flags:      /* (?i) */  
-           {
-                U32 posflags = 0, negflags = 0;
-               U32 *flagsp = &posflags;
-                bool has_charset_modifier = 0;
-               regex_charset cs = REGEX_DEPENDS_CHARSET;
-
-               while (*RExC_parse) {
-                   /* && strchr("iogcmsx", *RExC_parse) */
-                   /* (?g), (?gc) and (?o) are useless here
-                      and must be globally applied -- japhy */
-                    switch (*RExC_parse) {
-                   CASE_STD_PMMOD_FLAGS_PARSE_SET(flagsp);
-                    case LOCALE_PAT_MOD:
-                        if (has_charset_modifier || flagsp == &negflags) {
-                            goto fail_modifiers;
-                        }
-                       cs = REGEX_LOCALE_CHARSET;
-                        has_charset_modifier = 1;
-                        break;
-                    case UNICODE_PAT_MOD:
-                        if (has_charset_modifier || flagsp == &negflags) {
-                            goto fail_modifiers;
-                        }
-                       cs = REGEX_UNICODE_CHARSET;
-                        has_charset_modifier = 1;
-                        break;
-                    case ASCII_RESTRICT_PAT_MOD:
-                        if (has_charset_modifier || flagsp == &negflags) {
-                            goto fail_modifiers;
-                        }
-                       cs = REGEX_ASCII_RESTRICTED_CHARSET;
-                        has_charset_modifier = 1;
-                        break;
-                    case DEPENDS_PAT_MOD:
-                        if (has_use_defaults
-                            || has_charset_modifier
-                            || flagsp == &negflags)
-                        {
-                            goto fail_modifiers;
-                        }
-
-                       /* The dual charset means unicode semantics if the
-                        * pattern (or target, not known until runtime) are
-                        * utf8 */
-                       cs = (RExC_utf8)
-                            ? REGEX_UNICODE_CHARSET
-                            : REGEX_DEPENDS_CHARSET;
-                        has_charset_modifier = 1;
-                        break;
-                    case ONCE_PAT_MOD: /* 'o' */
-                    case GLOBAL_PAT_MOD: /* 'g' */
-                       if (SIZE_ONLY && ckWARN(WARN_REGEXP)) {
-                           const I32 wflagbit = *RExC_parse == 'o' ? WASTED_O : WASTED_G;
-                           if (! (wastedflags & wflagbit) ) {
-                               wastedflags |= wflagbit;
-                               vWARN5(
-                                   RExC_parse + 1,
-                                   "Useless (%s%c) - %suse /%c modifier",
-                                   flagsp == &negflags ? "?-" : "?",
-                                   *RExC_parse,
-                                   flagsp == &negflags ? "don't " : "",
-                                   *RExC_parse
-                               );
-                           }
-                       }
-                       break;
-                       
-                   case CONTINUE_PAT_MOD: /* 'c' */
-                       if (SIZE_ONLY && ckWARN(WARN_REGEXP)) {
-                           if (! (wastedflags & WASTED_C) ) {
-                               wastedflags |= WASTED_GC;
-                               vWARN3(
-                                   RExC_parse + 1,
-                                   "Useless (%sc) - %suse /gc modifier",
-                                   flagsp == &negflags ? "?-" : "?",
-                                   flagsp == &negflags ? "don't " : ""
-                               );
-                           }
-                       }
-                       break;
-                   case KEEPCOPY_PAT_MOD: /* 'p' */
-                        if (flagsp == &negflags) {
-                            if (SIZE_ONLY)
-                                ckWARNreg(RExC_parse + 1,"Useless use of (?-p)");
-                        } else {
-                            *flagsp |= RXf_PMf_KEEPCOPY;
-                        }
-                       break;
-                    case '-':
-                        /* A flag is a default iff it is following a minus, so
-                         * if there is a minus, it means will be trying to
-                         * re-specify a default which is an error */
-                        if (has_use_defaults || flagsp == &negflags) {
-            fail_modifiers:
-                            RExC_parse++;
-                           vFAIL3("Sequence (%.*s...) not recognized", RExC_parse-seqstart, seqstart);
-                           /*NOTREACHED*/
-                       }
-                       flagsp = &negflags;
-                       wastedflags = 0;  /* reset so (?g-c) warns twice */
-                       break;
-                    case ':':
-                       paren = ':';
-                       /*FALLTHROUGH*/
-                    case ')':
-                        RExC_flags |= posflags;
-                        RExC_flags &= ~negflags;
-                       set_regex_charset(&RExC_flags, cs);
-                        if (paren != ':') {
-                            oregflags |= posflags;
-                            oregflags &= ~negflags;
-                           set_regex_charset(&oregflags, cs);
-                        }
-                        nextchar(pRExC_state);
-                       if (paren != ':') {
-                           *flagp = TRYAGAIN;
-                           return NULL;
-                       } else {
-                            ret = NULL;
-                           goto parse_rest;
-                       }
-                       /*NOTREACHED*/
-                    default:
-                       RExC_parse++;
-                       vFAIL3("Sequence (%.*s...) not recognized", RExC_parse-seqstart, seqstart);
-                       /*NOTREACHED*/
-                    }                           
-                   ++RExC_parse;
-               }
-           }} /* one for the default block, one for the switch */
-       }
-       else {                  /* (...) */
-         capturing_parens:
-           parno = RExC_npar;
-           RExC_npar++;
-           
-           ret = reganode(pRExC_state, OPEN, parno);
-           if (!SIZE_ONLY ){
-               if (!RExC_nestroot) 
-                   RExC_nestroot = parno;
-               if (RExC_seen & REG_SEEN_RECURSE
-                   && !RExC_open_parens[parno-1])
-               {
-                   DEBUG_OPTIMISE_MORE_r(PerlIO_printf(Perl_debug_log,
-                       "Setting open paren #%"IVdf" to %d\n", 
-                       (IV)parno, REG_NODE_NUM(ret)));
-                   RExC_open_parens[parno-1]= ret;
-               }
-           }
-            Set_Node_Length(ret, 1); /* MJD */
-            Set_Node_Offset(ret, RExC_parse); /* MJD */
-           is_open = 1;
-       }
-    }
-    else                        /* ! paren */
-       ret = NULL;
-   
-   parse_rest:
-    /* Pick up the branches, linking them together. */
-    parse_start = RExC_parse;   /* MJD */
-    br = regbranch(pRExC_state, &flags, 1,depth+1);
-
-    if (freeze_paren) {
-        if (RExC_npar > after_freeze)
-            after_freeze = RExC_npar;
-        RExC_npar = freeze_paren;
-    }
-
-    /*     branch_len = (paren != 0); */
-
-    if (br == NULL)
-       return(NULL);
-    if (*RExC_parse == '|') {
-       if (!SIZE_ONLY && RExC_extralen) {
-           reginsert(pRExC_state, BRANCHJ, br, depth+1);
-       }
-       else {                  /* MJD */
-           reginsert(pRExC_state, BRANCH, br, depth+1);
-            Set_Node_Length(br, paren != 0);
-            Set_Node_Offset_To_R(br-RExC_emit_start, parse_start-RExC_start);
-        }
-       have_branch = 1;
-       if (SIZE_ONLY)
-           RExC_extralen += 1;         /* For BRANCHJ-BRANCH. */
-    }
-    else if (paren == ':') {
-       *flagp |= flags&SIMPLE;
-    }
-    if (is_open) {                             /* Starts with OPEN. */
-        REGTAIL(pRExC_state, ret, br);          /* OPEN -> first. */
-    }
-    else if (paren != '?')             /* Not Conditional */
-       ret = br;
-    *flagp |= flags & (SPSTART | HASWIDTH | POSTPONED);
-    lastbr = br;
-    while (*RExC_parse == '|') {
-       if (!SIZE_ONLY && RExC_extralen) {
-           ender = reganode(pRExC_state, LONGJMP,0);
-            REGTAIL(pRExC_state, NEXTOPER(NEXTOPER(lastbr)), ender); /* Append to the previous. */
-       }
-       if (SIZE_ONLY)
-           RExC_extralen += 2;         /* Account for LONGJMP. */
-       nextchar(pRExC_state);
-       if (freeze_paren) {
-           if (RExC_npar > after_freeze)
-               after_freeze = RExC_npar;
-            RExC_npar = freeze_paren;      
-        }
-        br = regbranch(pRExC_state, &flags, 0, depth+1);
-
-       if (br == NULL)
-           return(NULL);
-        REGTAIL(pRExC_state, lastbr, br);               /* BRANCH -> BRANCH. */
-       lastbr = br;
-       *flagp |= flags & (SPSTART | HASWIDTH | POSTPONED);
-    }
-
-    if (have_branch || paren != ':') {
-       /* Make a closing node, and hook it on the end. */
-       switch (paren) {
-       case ':':
-           ender = reg_node(pRExC_state, TAIL);
-           break;
-       case 1:
-           ender = reganode(pRExC_state, CLOSE, parno);
-           if (!SIZE_ONLY && RExC_seen & REG_SEEN_RECURSE) {
-               DEBUG_OPTIMISE_MORE_r(PerlIO_printf(Perl_debug_log,
-                       "Setting close paren #%"IVdf" to %d\n", 
-                       (IV)parno, REG_NODE_NUM(ender)));
-               RExC_close_parens[parno-1]= ender;
-               if (RExC_nestroot == parno) 
-                   RExC_nestroot = 0;
-           }       
-            Set_Node_Offset(ender,RExC_parse+1); /* MJD */
-            Set_Node_Length(ender,1); /* MJD */
-           break;
-       case '<':
-       case ',':
-       case '=':
-       case '!':
-           *flagp &= ~HASWIDTH;
-           /* FALL THROUGH */
-       case '>':
-           ender = reg_node(pRExC_state, SUCCEED);
-           break;
-       case 0:
-           ender = reg_node(pRExC_state, END);
-           if (!SIZE_ONLY) {
-                assert(!RExC_opend); /* there can only be one! */
-                RExC_opend = ender;
-            }
-           break;
-       }
-        REGTAIL(pRExC_state, lastbr, ender);
-
-       if (have_branch && !SIZE_ONLY) {
-           if (depth==1)
-               RExC_seen |= REG_TOP_LEVEL_BRANCHES;
-
-           /* Hook the tails of the branches to the closing node. */
-           for (br = ret; br; br = regnext(br)) {
-               const U8 op = PL_regkind[OP(br)];
-               if (op == BRANCH) {
-                    REGTAIL_STUDY(pRExC_state, NEXTOPER(br), ender);
-               }
-               else if (op == BRANCHJ) {
-                    REGTAIL_STUDY(pRExC_state, NEXTOPER(NEXTOPER(br)), ender);
-               }
-           }
-       }
-    }
-
-    {
-        const char *p;
-        static const char parens[] = "=!<,>";
-
-       if (paren && (p = strchr(parens, paren))) {
-           U8 node = ((p - parens) % 2) ? UNLESSM : IFMATCH;
-           int flag = (p - parens) > 1;
-
-           if (paren == '>')
-               node = SUSPEND, flag = 0;
-           reginsert(pRExC_state, node,ret, depth+1);
-           Set_Node_Cur_Length(ret);
-           Set_Node_Offset(ret, parse_start + 1);
-           ret->flags = flag;
-            REGTAIL_STUDY(pRExC_state, ret, reg_node(pRExC_state, TAIL));
-       }
-    }
-
-    /* Check for proper termination. */
-    if (paren) {
-       RExC_flags = oregflags;
-       if (RExC_parse >= RExC_end || *nextchar(pRExC_state) != ')') {
-           RExC_parse = oregcomp_parse;
-           vFAIL("Unmatched (");
-       }
-    }
-    else if (!paren && RExC_parse < RExC_end) {
-       if (*RExC_parse == ')') {
-           RExC_parse++;
-           vFAIL("Unmatched )");
-       }
-       else
-           FAIL("Junk on end of regexp");      /* "Can't happen". */
-       /* NOTREACHED */
-    }
-
-    if (RExC_in_lookbehind) {
-       RExC_in_lookbehind--;
-    }
-    if (after_freeze)
-        RExC_npar = after_freeze;
-    return(ret);
-}
-
-/*
- - regbranch - one alternative of an | operator
- *
- * Implements the concatenation operator.
- */
-STATIC regnode *
-S_regbranch(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, I32 first, U32 depth)
-{
-    dVAR;
-    register regnode *ret;
-    register regnode *chain = NULL;
-    register regnode *latest;
-    I32 flags = 0, c = 0;
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_REGBRANCH;
-
-    DEBUG_PARSE("brnc");
-
-    if (first)
-       ret = NULL;
-    else {
-       if (!SIZE_ONLY && RExC_extralen)
-           ret = reganode(pRExC_state, BRANCHJ,0);
-       else {
-           ret = reg_node(pRExC_state, BRANCH);
-            Set_Node_Length(ret, 1);
-        }
-    }
-       
-    if (!first && SIZE_ONLY)
-       RExC_extralen += 1;                     /* BRANCHJ */
-
-    *flagp = WORST;                    /* Tentatively. */
-
-    RExC_parse--;
-    nextchar(pRExC_state);
-    while (RExC_parse < RExC_end && *RExC_parse != '|' && *RExC_parse != ')') {
-       flags &= ~TRYAGAIN;
-        latest = regpiece(pRExC_state, &flags,depth+1);
-       if (latest == NULL) {
-           if (flags & TRYAGAIN)
-               continue;
-           return(NULL);
-       }
-       else if (ret == NULL)
-           ret = latest;
-       *flagp |= flags&(HASWIDTH|POSTPONED);
-       if (chain == NULL)      /* First piece. */
-           *flagp |= flags&SPSTART;
-       else {
-           RExC_naughty++;
-            REGTAIL(pRExC_state, chain, latest);
-       }
-       chain = latest;
-       c++;
-    }
-    if (chain == NULL) {       /* Loop ran zero times. */
-       chain = reg_node(pRExC_state, NOTHING);
-       if (ret == NULL)
-           ret = chain;
-    }
-    if (c == 1) {
-       *flagp |= flags&SIMPLE;
-    }
-
-    return ret;
-}
-
-/*
- - regpiece - something followed by possible [*+?]
- *
- * Note that the branching code sequences used for ? and the general cases
- * of * and + are somewhat optimized:  they use the same NOTHING node as
- * both the endmarker for their branch list and the body of the last branch.
- * It might seem that this node could be dispensed with entirely, but the
- * endmarker role is not redundant.
- */
-STATIC regnode *
-S_regpiece(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, U32 depth)
-{
-    dVAR;
-    register regnode *ret;
-    register char op;
-    register char *next;
-    I32 flags;
-    const char * const origparse = RExC_parse;
-    I32 min;
-    I32 max = REG_INFTY;
-    char *parse_start;
-    const char *maxpos = NULL;
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_REGPIECE;
-
-    DEBUG_PARSE("piec");
-
-    ret = regatom(pRExC_state, &flags,depth+1);
-    if (ret == NULL) {
-       if (flags & TRYAGAIN)
-           *flagp |= TRYAGAIN;
-       return(NULL);
-    }
-
-    op = *RExC_parse;
-
-    if (op == '{' && regcurly(RExC_parse)) {
-       maxpos = NULL;
-        parse_start = RExC_parse; /* MJD */
-       next = RExC_parse + 1;
-       while (isDIGIT(*next) || *next == ',') {
-           if (*next == ',') {
-               if (maxpos)
-                   break;
-               else
-                   maxpos = next;
-           }
-           next++;
-       }
-       if (*next == '}') {             /* got one */
-           if (!maxpos)
-               maxpos = next;
-           RExC_parse++;
-           min = atoi(RExC_parse);
-           if (*maxpos == ',')
-               maxpos++;
-           else
-               maxpos = RExC_parse;
-           max = atoi(maxpos);
-           if (!max && *maxpos != '0')
-               max = REG_INFTY;                /* meaning "infinity" */
-           else if (max >= REG_INFTY)
-               vFAIL2("Quantifier in {,} bigger than %d", REG_INFTY - 1);
-           RExC_parse = next;
-           nextchar(pRExC_state);
-
-       do_curly:
-           if ((flags&SIMPLE)) {
-               RExC_naughty += 2 + RExC_naughty / 2;
-               reginsert(pRExC_state, CURLY, ret, depth+1);
-                Set_Node_Offset(ret, parse_start+1); /* MJD */
-                Set_Node_Cur_Length(ret);
-           }
-           else {
-               regnode * const w = reg_node(pRExC_state, WHILEM);
-
-               w->flags = 0;
-                REGTAIL(pRExC_state, ret, w);
-               if (!SIZE_ONLY && RExC_extralen) {
-                   reginsert(pRExC_state, LONGJMP,ret, depth+1);
-                   reginsert(pRExC_state, NOTHING,ret, depth+1);
-                   NEXT_OFF(ret) = 3;  /* Go over LONGJMP. */
-               }
-               reginsert(pRExC_state, CURLYX,ret, depth+1);
-                                /* MJD hk */
-                Set_Node_Offset(ret, parse_start+1);
-                Set_Node_Length(ret,
-                                op == '{' ? (RExC_parse - parse_start) : 1);
-
-               if (!SIZE_ONLY && RExC_extralen)
-                   NEXT_OFF(ret) = 3;  /* Go over NOTHING to LONGJMP. */
-                REGTAIL(pRExC_state, ret, reg_node(pRExC_state, NOTHING));
-               if (SIZE_ONLY)
-                   RExC_whilem_seen++, RExC_extralen += 3;
-               RExC_naughty += 4 + RExC_naughty;       /* compound interest */
-           }
-           ret->flags = 0;
-
-           if (min > 0)
-               *flagp = WORST;
-           if (max > 0)
-               *flagp |= HASWIDTH;
-           if (max < min)
-               vFAIL("Can't do {n,m} with n > m");
-           if (!SIZE_ONLY) {
-               ARG1_SET(ret, (U16)min);
-               ARG2_SET(ret, (U16)max);
-           }
-
-           goto nest_check;
-       }
-    }
-
-    if (!ISMULT1(op)) {
-       *flagp = flags;
-       return(ret);
-    }
-
-#if 0                          /* Now runtime fix should be reliable. */
-
-    /* if this is reinstated, don't forget to put this back into perldiag:
-
-           =item Regexp *+ operand could be empty at {#} in regex m/%s/
-
-          (F) The part of the regexp subject to either the * or + quantifier
-           could match an empty string. The {#} shows in the regular
-           expression about where the problem was discovered.
-
-    */
-
-    if (!(flags&HASWIDTH) && op != '?')
-      vFAIL("Regexp *+ operand could be empty");
-#endif
-
-    parse_start = RExC_parse;
-    nextchar(pRExC_state);
-
-    *flagp = (op != '+') ? (WORST|SPSTART|HASWIDTH) : (WORST|HASWIDTH);
-
-    if (op == '*' && (flags&SIMPLE)) {
-       reginsert(pRExC_state, STAR, ret, depth+1);
-       ret->flags = 0;
-       RExC_naughty += 4;
-    }
-    else if (op == '*') {
-       min = 0;
-       goto do_curly;
-    }
-    else if (op == '+' && (flags&SIMPLE)) {
-       reginsert(pRExC_state, PLUS, ret, depth+1);
-       ret->flags = 0;
-       RExC_naughty += 3;
-    }
-    else if (op == '+') {
-       min = 1;
-       goto do_curly;
-    }
-    else if (op == '?') {
-       min = 0; max = 1;
-       goto do_curly;
-    }
-  nest_check:
-    if (!SIZE_ONLY && !(flags&(HASWIDTH|POSTPONED)) && max > REG_INFTY/3) {
-       ckWARN3reg(RExC_parse,
-                  "%.*s matches null string many times",
-                  (int)(RExC_parse >= origparse ? RExC_parse - origparse : 0),
-                  origparse);
-    }
-
-    if (RExC_parse < RExC_end && *RExC_parse == '?') {
-       nextchar(pRExC_state);
-       reginsert(pRExC_state, MINMOD, ret, depth+1);
-        REGTAIL(pRExC_state, ret, ret + NODE_STEP_REGNODE);
-    }
-#ifndef REG_ALLOW_MINMOD_SUSPEND
-    else
-#endif
-    if (RExC_parse < RExC_end && *RExC_parse == '+') {
-        regnode *ender;
-        nextchar(pRExC_state);
-        ender = reg_node(pRExC_state, SUCCEED);
-        REGTAIL(pRExC_state, ret, ender);
-        reginsert(pRExC_state, SUSPEND, ret, depth+1);
-        ret->flags = 0;
-        ender = reg_node(pRExC_state, TAIL);
-        REGTAIL(pRExC_state, ret, ender);
-        /*ret= ender;*/
-    }
-
-    if (RExC_parse < RExC_end && ISMULT2(RExC_parse)) {
-       RExC_parse++;
-       vFAIL("Nested quantifiers");
-    }
-
-    return(ret);
-}
-
-
-/* reg_namedseq(pRExC_state,UVp)
-   
-   This is expected to be called by a parser routine that has 
-   recognized '\N' and needs to handle the rest. RExC_parse is
-   expected to point at the first char following the N at the time
-   of the call.
-
-   The \N may be inside (indicated by valuep not being NULL) or outside a
-   character class.
-
-   \N may begin either a named sequence, or if outside a character class, mean
-   to match a non-newline.  For non single-quoted regexes, the tokenizer has
-   attempted to decide which, and in the case of a named sequence converted it
-   into one of the forms: \N{} (if the sequence is null), or \N{U+c1.c2...},
-   where c1... are the characters in the sequence.  For single-quoted regexes,
-   the tokenizer passes the \N sequence through unchanged; this code will not
-   attempt to determine this nor expand those.  The net effect is that if the
-   beginning of the passed-in pattern isn't '{U+' or there is no '}', it
-   signals that this \N occurrence means to match a non-newline.
-   
-   Only the \N{U+...} form should occur in a character class, for the same
-   reason that '.' inside a character class means to just match a period: it
-   just doesn't make sense.
-   
-   If valuep is non-null then it is assumed that we are parsing inside 
-   of a charclass definition and the first codepoint in the resolved
-   string is returned via *valuep and the routine will return NULL. 
-   In this mode if a multichar string is returned from the charnames 
-   handler, a warning will be issued, and only the first char in the 
-   sequence will be examined. If the string returned is zero length
-   then the value of *valuep is undefined and NON-NULL will 
-   be returned to indicate failure. (This will NOT be a valid pointer 
-   to a regnode.)
-   
-   If valuep is null then it is assumed that we are parsing normal text and a
-   new EXACT node is inserted into the program containing the resolved string,
-   and a pointer to the new node is returned.  But if the string is zero length
-   a NOTHING node is emitted instead.
-
-   On success RExC_parse is set to the char following the endbrace.
-   Parsing failures will generate a fatal error via vFAIL(...)
- */
-STATIC regnode *
-S_reg_namedseq(pTHX_ RExC_state_t *pRExC_state, UV *valuep, I32 *flagp)
-{
-    char * endbrace;    /* '}' following the name */
-    regnode *ret = NULL;
-#ifdef DEBUGGING
-    char* parse_start = RExC_parse - 2;            /* points to the '\N' */
-#endif
-    char* p;
-
-    GET_RE_DEBUG_FLAGS_DECL;
-    PERL_ARGS_ASSERT_REG_NAMEDSEQ;
-
-    GET_RE_DEBUG_FLAGS;
-
-    /* The [^\n] meaning of \N ignores spaces and comments under the /x
-     * modifier.  The other meaning does not */
-    p = (RExC_flags & RXf_PMf_EXTENDED)
-       ? regwhite( pRExC_state, RExC_parse )
-       : RExC_parse;
-   
-    /* Disambiguate between \N meaning a named character versus \N meaning
-     * [^\n].  The former is assumed when it can't be the latter. */
-    if (*p != '{' || regcurly(p)) {
-       RExC_parse = p;
-       if (valuep) {
-           /* no bare \N in a charclass */
-           vFAIL("\\N in a character class must be a named character: \\N{...}");
-       }
-       nextchar(pRExC_state);
-       ret = reg_node(pRExC_state, REG_ANY);
-       *flagp |= HASWIDTH|SIMPLE;
-       RExC_naughty++;
-       RExC_parse--;
-        Set_Node_Length(ret, 1); /* MJD */
-       return ret;
-    }
-
-    /* Here, we have decided it should be a named sequence */
-
-    /* The test above made sure that the next real character is a '{', but
-     * under the /x modifier, it could be separated by space (or a comment and
-     * \n) and this is not allowed (for consistency with \x{...} and the
-     * tokenizer handling of \N{NAME}). */
-    if (*RExC_parse != '{') {
-       vFAIL("Missing braces on \\N{}");
-    }
-
-    RExC_parse++;      /* Skip past the '{' */
-
-    if (! (endbrace = strchr(RExC_parse, '}')) /* no trailing brace */
-       || ! (endbrace == RExC_parse            /* nothing between the {} */
-             || (endbrace - RExC_parse >= 2    /* U+ (bad hex is checked below */
-                 && strnEQ(RExC_parse, "U+", 2)))) /* for a better error msg) */
-    {
-       if (endbrace) RExC_parse = endbrace;    /* position msg's '<--HERE' */
-       vFAIL("\\N{NAME} must be resolved by the lexer");
-    }
-
-    if (endbrace == RExC_parse) {   /* empty: \N{} */
-       if (! valuep) {
-           RExC_parse = endbrace + 1;  
-           return reg_node(pRExC_state,NOTHING);
-       }
-
-       if (SIZE_ONLY) {
-           ckWARNreg(RExC_parse,
-                   "Ignoring zero length \\N{} in character class"
-           );
-           RExC_parse = endbrace + 1;  
-       }
-       *valuep = 0;
-       return (regnode *) &RExC_parse; /* Invalid regnode pointer */
-    }
-
-    REQUIRE_UTF8;      /* named sequences imply Unicode semantics */
-    RExC_parse += 2;   /* Skip past the 'U+' */
-
-    if (valuep) {   /* In a bracketed char class */
-       /* We only pay attention to the first char of 
-       multichar strings being returned. I kinda wonder
-       if this makes sense as it does change the behaviour
-       from earlier versions, OTOH that behaviour was broken
-       as well. XXX Solution is to recharacterize as
-       [rest-of-class]|multi1|multi2... */
-
-       STRLEN length_of_hex;
-       I32 flags = PERL_SCAN_ALLOW_UNDERSCORES
-           | PERL_SCAN_DISALLOW_PREFIX
-           | (SIZE_ONLY ? PERL_SCAN_SILENT_ILLDIGIT : 0);
-    
-       char * endchar = RExC_parse + strcspn(RExC_parse, ".}");
-       if (endchar < endbrace) {
-           ckWARNreg(endchar, "Using just the first character returned by \\N{} in character class");
-       }
-
-       length_of_hex = (STRLEN)(endchar - RExC_parse);
-       *valuep = grok_hex(RExC_parse, &length_of_hex, &flags, NULL);
-
-       /* The tokenizer should have guaranteed validity, but it's possible to
-        * bypass it by using single quoting, so check */
-       if (length_of_hex == 0
-           || length_of_hex != (STRLEN)(endchar - RExC_parse) )
-       {
-           RExC_parse += length_of_hex;        /* Includes all the valid */
-           RExC_parse += (RExC_orig_utf8)      /* point to after 1st invalid */
-                           ? UTF8SKIP(RExC_parse)
-                           : 1;
-           /* Guard against malformed utf8 */
-           if (RExC_parse >= endchar) RExC_parse = endchar;
-           vFAIL("Invalid hexadecimal number in \\N{U+...}");
-       }    
-
-       RExC_parse = endbrace + 1;
-       if (endchar == endbrace) return NULL;
-
-        ret = (regnode *) &RExC_parse; /* Invalid regnode pointer */
-    }
-    else {     /* Not a char class */
-       char *s;            /* String to put in generated EXACT node */
-       STRLEN len = 0;     /* Its current byte length */
-       char *endchar;      /* Points to '.' or '}' ending cur char in the input
-                              stream */
-
-       ret = reg_node(pRExC_state, (U8) ((! FOLD) ? EXACT
-                                                  : (LOC)
-                                                     ? EXACTFL
-                                                     : UNI_SEMANTICS
-                                                       ? EXACTFU
-                                                       : EXACTF));
-       s= STRING(ret);
-
-       /* Exact nodes can hold only a U8 length's of text = 255.  Loop through
-        * the input which is of the form now 'c1.c2.c3...}' until find the
-        * ending brace or exceed length 255.  The characters that exceed this
-        * limit are dropped.  The limit could be relaxed should it become
-        * desirable by reparsing this as (?:\N{NAME}), so could generate
-        * multiple EXACT nodes, as is done for just regular input.  But this
-        * is primarily a named character, and not intended to be a huge long
-        * string, so 255 bytes should be good enough */
-       while (1) {
-           STRLEN length_of_hex;
-           I32 grok_flags = PERL_SCAN_ALLOW_UNDERSCORES
-                           | PERL_SCAN_DISALLOW_PREFIX
-                           | (SIZE_ONLY ? PERL_SCAN_SILENT_ILLDIGIT : 0);
-           UV cp;  /* Ord of current character */
-
-           /* Code points are separated by dots.  If none, there is only one
-            * code point, and is terminated by the brace */
-           endchar = RExC_parse + strcspn(RExC_parse, ".}");
-
-           /* The values are Unicode even on EBCDIC machines */
-           length_of_hex = (STRLEN)(endchar - RExC_parse);
-           cp = grok_hex(RExC_parse, &length_of_hex, &grok_flags, NULL);
-           if ( length_of_hex == 0 
-               || length_of_hex != (STRLEN)(endchar - RExC_parse) )
-           {
-               RExC_parse += length_of_hex;        /* Includes all the valid */
-               RExC_parse += (RExC_orig_utf8)  /* point to after 1st invalid */
-                               ? UTF8SKIP(RExC_parse)
-                               : 1;
-               /* Guard against malformed utf8 */
-               if (RExC_parse >= endchar) RExC_parse = endchar;
-               vFAIL("Invalid hexadecimal number in \\N{U+...}");
-           }    
-
-           if (! FOLD) {       /* Not folding, just append to the string */
-               STRLEN unilen;
-
-               /* Quit before adding this character if would exceed limit */
-               if (len + UNISKIP(cp) > U8_MAX) break;
-
-               unilen = reguni(pRExC_state, cp, s);
-               if (unilen > 0) {
-                   s   += unilen;
-                   len += unilen;
-               }
-           } else {    /* Folding, output the folded equivalent */
-               STRLEN foldlen,numlen;
-               U8 tmpbuf[UTF8_MAXBYTES_CASE+1], *foldbuf;
-               cp = toFOLD_uni(cp, tmpbuf, &foldlen);
-
-               /* Quit before exceeding size limit */
-               if (len + foldlen > U8_MAX) break;
-               
-               for (foldbuf = tmpbuf;
-                   foldlen;
-                   foldlen -= numlen) 
-               {
-                   cp = utf8_to_uvchr(foldbuf, &numlen);
-                   if (numlen > 0) {
-                       const STRLEN unilen = reguni(pRExC_state, cp, s);
-                       s       += unilen;
-                       len     += unilen;
-                       /* In EBCDIC the numlen and unilen can differ. */
-                       foldbuf += numlen;
-                       if (numlen >= foldlen)
-                           break;
-                   }
-                   else
-                       break; /* "Can't happen." */
-               }                          
-           }
-
-           /* Point to the beginning of the next character in the sequence. */
-           RExC_parse = endchar + 1;
-
-           /* Quit if no more characters */
-           if (RExC_parse >= endbrace) break;
-       }
-
-
-       if (SIZE_ONLY) {
-           if (RExC_parse < endbrace) {
-               ckWARNreg(RExC_parse - 1,
-                         "Using just the first characters returned by \\N{}");
-           }
-
-           RExC_size += STR_SZ(len);
-       } else {
-           STR_LEN(ret) = len;
-           RExC_emit += STR_SZ(len);
-       }
-
-       RExC_parse = endbrace + 1;
-
-       *flagp |= HASWIDTH; /* Not SIMPLE, as that causes the engine to fail
-                              with malformed in t/re/pat_advanced.t */
-       RExC_parse --;
-       Set_Node_Cur_Length(ret); /* MJD */
-       nextchar(pRExC_state);
-    }
-
-    return ret;
-}
-
-
-/*
- * reg_recode
- *
- * It returns the code point in utf8 for the value in *encp.
- *    value: a code value in the source encoding
- *    encp:  a pointer to an Encode object
- *
- * If the result from Encode is not a single character,
- * it returns U+FFFD (Replacement character) and sets *encp to NULL.
- */
-STATIC UV
-S_reg_recode(pTHX_ const char value, SV **encp)
-{
-    STRLEN numlen = 1;
-    SV * const sv = newSVpvn_flags(&value, numlen, SVs_TEMP);
-    const char * const s = *encp ? sv_recode_to_utf8(sv, *encp) : SvPVX(sv);
-    const STRLEN newlen = SvCUR(sv);
-    UV uv = UNICODE_REPLACEMENT;
-
-    PERL_ARGS_ASSERT_REG_RECODE;
-
-    if (newlen)
-       uv = SvUTF8(sv)
-            ? utf8n_to_uvchr((U8*)s, newlen, &numlen, UTF8_ALLOW_DEFAULT)
-            : *(U8*)s;
-
-    if (!newlen || numlen != newlen) {
-       uv = UNICODE_REPLACEMENT;
-       *encp = NULL;
-    }
-    return uv;
-}
-
-
-/*
- - regatom - the lowest level
-
-   Try to identify anything special at the start of the pattern. If there
-   is, then handle it as required. This may involve generating a single regop,
-   such as for an assertion; or it may involve recursing, such as to
-   handle a () structure.
-
-   If the string doesn't start with something special then we gobble up
-   as much literal text as we can.
-
-   Once we have been able to handle whatever type of thing started the
-   sequence, we return.
-
-   Note: we have to be careful with escapes, as they can be both literal
-   and special, and in the case of \10 and friends can either, depending
-   on context. Specifically there are two separate switches for handling
-   escape sequences, with the one for handling literal escapes requiring
-   a dummy entry for all of the special escapes that are actually handled
-   by the other.
-*/
-
-STATIC regnode *
-S_regatom(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, U32 depth)
-{
-    dVAR;
-    register regnode *ret = NULL;
-    I32 flags;
-    char *parse_start = RExC_parse;
-    U8 op;
-    GET_RE_DEBUG_FLAGS_DECL;
-    DEBUG_PARSE("atom");
-    *flagp = WORST;            /* Tentatively. */
-
-    PERL_ARGS_ASSERT_REGATOM;
-
-tryagain:
-    switch ((U8)*RExC_parse) {
-    case '^':
-       RExC_seen_zerolen++;
-       nextchar(pRExC_state);
-       if (RExC_flags & RXf_PMf_MULTILINE)
-           ret = reg_node(pRExC_state, MBOL);
-       else if (RExC_flags & RXf_PMf_SINGLELINE)
-           ret = reg_node(pRExC_state, SBOL);
-       else
-           ret = reg_node(pRExC_state, BOL);
-        Set_Node_Length(ret, 1); /* MJD */
-       break;
-    case '$':
-       nextchar(pRExC_state);
-       if (*RExC_parse)
-           RExC_seen_zerolen++;
-       if (RExC_flags & RXf_PMf_MULTILINE)
-           ret = reg_node(pRExC_state, MEOL);
-       else if (RExC_flags & RXf_PMf_SINGLELINE)
-           ret = reg_node(pRExC_state, SEOL);
-       else
-           ret = reg_node(pRExC_state, EOL);
-        Set_Node_Length(ret, 1); /* MJD */
-       break;
-    case '.':
-       nextchar(pRExC_state);
-       if (RExC_flags & RXf_PMf_SINGLELINE)
-           ret = reg_node(pRExC_state, SANY);
-       else
-           ret = reg_node(pRExC_state, REG_ANY);
-       *flagp |= HASWIDTH|SIMPLE;
-       RExC_naughty++;
-        Set_Node_Length(ret, 1); /* MJD */
-       break;
-    case '[':
-    {
-       char * const oregcomp_parse = ++RExC_parse;
-        ret = regclass(pRExC_state,depth+1);
-       if (*RExC_parse != ']') {
-           RExC_parse = oregcomp_parse;
-           vFAIL("Unmatched [");
-       }
-       nextchar(pRExC_state);
-       *flagp |= HASWIDTH|SIMPLE;
-        Set_Node_Length(ret, RExC_parse - oregcomp_parse + 1); /* MJD */
-       break;
-    }
-    case '(':
-       nextchar(pRExC_state);
-        ret = reg(pRExC_state, 1, &flags,depth+1);
-       if (ret == NULL) {
-               if (flags & TRYAGAIN) {
-                   if (RExC_parse == RExC_end) {
-                        /* Make parent create an empty node if needed. */
-                       *flagp |= TRYAGAIN;
-                       return(NULL);
-                   }
-                   goto tryagain;
-               }
-               return(NULL);
-       }
-       *flagp |= flags&(HASWIDTH|SPSTART|SIMPLE|POSTPONED);
-       break;
-    case '|':
-    case ')':
-       if (flags & TRYAGAIN) {
-           *flagp |= TRYAGAIN;
-           return NULL;
-       }
-       vFAIL("Internal urp");
-                               /* Supposed to be caught earlier. */
-       break;
-    case '{':
-       if (!regcurly(RExC_parse)) {
-           RExC_parse++;
-           goto defchar;
-       }
-       /* FALL THROUGH */
-    case '?':
-    case '+':
-    case '*':
-       RExC_parse++;
-       vFAIL("Quantifier follows nothing");
-       break;
-    case LATIN_SMALL_LETTER_SHARP_S:
-    case UTF8_TWO_BYTE_HI_nocast(LATIN_SMALL_LETTER_SHARP_S):
-    case UTF8_TWO_BYTE_HI_nocast(IOTA_D_T):
-#if UTF8_TWO_BYTE_HI_nocast(UPSILON_D_T) != UTF8_TWO_BYTE_HI_nocast(IOTA_D_T)
-#error The beginning utf8 byte of IOTA_D_T and UPSILON_D_T unexpectedly differ.  Other instances in this code should have the case statement below.
-    case UTF8_TWO_BYTE_HI_nocast(UPSILON_D_T):
-#endif
-        do_foldchar:
-        if (!LOC && FOLD) {
-            U32 len,cp;
-           len=0; /* silence a spurious compiler warning */
-            if ((cp = what_len_TRICKYFOLD_safe(RExC_parse,RExC_end,UTF,len))) {
-                *flagp |= HASWIDTH; /* could be SIMPLE too, but needs a handler in regexec.regrepeat */
-                RExC_parse+=len-1; /* we get one from nextchar() as well. :-( */
-                ret = reganode(pRExC_state, FOLDCHAR, cp);
-                Set_Node_Length(ret, 1); /* MJD */
-                nextchar(pRExC_state); /* kill whitespace under /x */
-                return ret;
-            }
-        }
-        goto outer_default;
-    case '\\':
-       /* Special Escapes
-
-          This switch handles escape sequences that resolve to some kind
-          of special regop and not to literal text. Escape sequnces that
-          resolve to literal text are handled below in the switch marked
-          "Literal Escapes".
-
-          Every entry in this switch *must* have a corresponding entry
-          in the literal escape switch. However, the opposite is not
-          required, as the default for this switch is to jump to the
-          literal text handling code.
-       */
-       switch ((U8)*++RExC_parse) {
-       case LATIN_SMALL_LETTER_SHARP_S:
-       case UTF8_TWO_BYTE_HI_nocast(LATIN_SMALL_LETTER_SHARP_S):
-       case UTF8_TWO_BYTE_HI_nocast(IOTA_D_T):
-                  goto do_foldchar;        
-       /* Special Escapes */
-       case 'A':
-           RExC_seen_zerolen++;
-           ret = reg_node(pRExC_state, SBOL);
-           *flagp |= SIMPLE;
-           goto finish_meta_pat;
-       case 'G':
-           ret = reg_node(pRExC_state, GPOS);
-           RExC_seen |= REG_SEEN_GPOS;
-           *flagp |= SIMPLE;
-           goto finish_meta_pat;
-       case 'K':
-           RExC_seen_zerolen++;
-           ret = reg_node(pRExC_state, KEEPS);
-           *flagp |= SIMPLE;
-           /* XXX:dmq : disabling in-place substitution seems to
-            * be necessary here to avoid cases of memory corruption, as
-            * with: C<$_="x" x 80; s/x\K/y/> -- rgs
-            */
-           RExC_seen |= REG_SEEN_LOOKBEHIND;
-           goto finish_meta_pat;
-       case 'Z':
-           ret = reg_node(pRExC_state, SEOL);
-           *flagp |= SIMPLE;
-           RExC_seen_zerolen++;                /* Do not optimize RE away */
-           goto finish_meta_pat;
-       case 'z':
-           ret = reg_node(pRExC_state, EOS);
-           *flagp |= SIMPLE;
-           RExC_seen_zerolen++;                /* Do not optimize RE away */
-           goto finish_meta_pat;
-       case 'C':
-           ret = reg_node(pRExC_state, CANY);
-           RExC_seen |= REG_SEEN_CANY;
-           *flagp |= HASWIDTH|SIMPLE;
-           goto finish_meta_pat;
-       case 'X':
-           ret = reg_node(pRExC_state, CLUMP);
-           *flagp |= HASWIDTH;
-           goto finish_meta_pat;
-       case 'w':
-           switch (get_regex_charset(RExC_flags)) {
-               case REGEX_LOCALE_CHARSET:
-                   op = ALNUML;
-                   break;
-               case REGEX_UNICODE_CHARSET:
-                   op = ALNUMU;
-                   break;
-               case REGEX_ASCII_RESTRICTED_CHARSET:
-                   op = ALNUMA;
-                   break;
-               case REGEX_DEPENDS_CHARSET:
-                   op = ALNUM;
-                   break;
-               default:
-                   goto bad_charset;
-            }
-           ret = reg_node(pRExC_state, op);
-           *flagp |= HASWIDTH|SIMPLE;
-           goto finish_meta_pat;
-       case 'W':
-           switch (get_regex_charset(RExC_flags)) {
-               case REGEX_LOCALE_CHARSET:
-                   op = NALNUML;
-                   break;
-               case REGEX_UNICODE_CHARSET:
-                   op = NALNUMU;
-                   break;
-               case REGEX_ASCII_RESTRICTED_CHARSET:
-                   op = NALNUMA;
-                   break;
-               case REGEX_DEPENDS_CHARSET:
-                   op = NALNUM;
-                   break;
-               default:
-                   goto bad_charset;
-            }
-           ret = reg_node(pRExC_state, op);
-           *flagp |= HASWIDTH|SIMPLE;
-           goto finish_meta_pat;
-       case 'b':
-           RExC_seen_zerolen++;
-           RExC_seen |= REG_SEEN_LOOKBEHIND;
-           switch (get_regex_charset(RExC_flags)) {
-               case REGEX_LOCALE_CHARSET:
-                   op = BOUNDL;
-                   break;
-               case REGEX_UNICODE_CHARSET:
-                   op = BOUNDU;
-                   break;
-               case REGEX_ASCII_RESTRICTED_CHARSET:
-                   op = BOUNDA;
-                   break;
-               case REGEX_DEPENDS_CHARSET:
-                   op = BOUND;
-                   break;
-               default:
-                   goto bad_charset;
-            }
-           ret = reg_node(pRExC_state, op);
-           FLAGS(ret) = get_regex_charset(RExC_flags);
-           *flagp |= SIMPLE;
-           goto finish_meta_pat;
-       case 'B':
-           RExC_seen_zerolen++;
-           RExC_seen |= REG_SEEN_LOOKBEHIND;
-           switch (get_regex_charset(RExC_flags)) {
-               case REGEX_LOCALE_CHARSET:
-                   op = NBOUNDL;
-                   break;
-               case REGEX_UNICODE_CHARSET:
-                   op = NBOUNDU;
-                   break;
-               case REGEX_ASCII_RESTRICTED_CHARSET:
-                   op = NBOUNDA;
-                   break;
-               case REGEX_DEPENDS_CHARSET:
-                   op = NBOUND;
-                   break;
-               default:
-                   goto bad_charset;
-            }
-           ret = reg_node(pRExC_state, op);
-           FLAGS(ret) = get_regex_charset(RExC_flags);
-           *flagp |= SIMPLE;
-           goto finish_meta_pat;
-       case 's':
-           switch (get_regex_charset(RExC_flags)) {
-               case REGEX_LOCALE_CHARSET:
-                   op = SPACEL;
-                   break;
-               case REGEX_UNICODE_CHARSET:
-                   op = SPACEU;
-                   break;
-               case REGEX_ASCII_RESTRICTED_CHARSET:
-                   op = SPACEA;
-                   break;
-               case REGEX_DEPENDS_CHARSET:
-                   op = SPACE;
-                   break;
-               default:
-                   goto bad_charset;
-            }
-           ret = reg_node(pRExC_state, op);
-           *flagp |= HASWIDTH|SIMPLE;
-           goto finish_meta_pat;
-       case 'S':
-           switch (get_regex_charset(RExC_flags)) {
-               case REGEX_LOCALE_CHARSET:
-                   op = NSPACEL;
-                   break;
-               case REGEX_UNICODE_CHARSET:
-                   op = NSPACEU;
-                   break;
-               case REGEX_ASCII_RESTRICTED_CHARSET:
-                   op = NSPACEA;
-                   break;
-               case REGEX_DEPENDS_CHARSET:
-                   op = NSPACE;
-                   break;
-               default:
-                   goto bad_charset;
-            }
-           ret = reg_node(pRExC_state, op);
-           *flagp |= HASWIDTH|SIMPLE;
-           goto finish_meta_pat;
-       case 'd':
-           switch (get_regex_charset(RExC_flags)) {
-               case REGEX_LOCALE_CHARSET:
-                   op = DIGITL;
-                   break;
-               case REGEX_ASCII_RESTRICTED_CHARSET:
-                   op = DIGITA;
-                   break;
-               case REGEX_DEPENDS_CHARSET: /* No difference between these */
-               case REGEX_UNICODE_CHARSET:
-                   op = DIGIT;
-                   break;
-               default:
-                   goto bad_charset;
-            }
-           ret = reg_node(pRExC_state, op);
-           *flagp |= HASWIDTH|SIMPLE;
-           goto finish_meta_pat;
-       case 'D':
-           switch (get_regex_charset(RExC_flags)) {
-               case REGEX_LOCALE_CHARSET:
-                   op = NDIGITL;
-                   break;
-               case REGEX_ASCII_RESTRICTED_CHARSET:
-                   op = NDIGITA;
-                   break;
-               case REGEX_DEPENDS_CHARSET: /* No difference between these */
-               case REGEX_UNICODE_CHARSET:
-                   op = NDIGIT;
-                   break;
-               default:
-                   goto bad_charset;
-            }
-           ret = reg_node(pRExC_state, op);
-           *flagp |= HASWIDTH|SIMPLE;
-           goto finish_meta_pat;
-       case 'R':
-           ret = reg_node(pRExC_state, LNBREAK);
-           *flagp |= HASWIDTH|SIMPLE;
-           goto finish_meta_pat;
-       case 'h':
-           ret = reg_node(pRExC_state, HORIZWS);
-           *flagp |= HASWIDTH|SIMPLE;
-           goto finish_meta_pat;
-       case 'H':
-           ret = reg_node(pRExC_state, NHORIZWS);
-           *flagp |= HASWIDTH|SIMPLE;
-           goto finish_meta_pat;
-       case 'v':
-           ret = reg_node(pRExC_state, VERTWS);
-           *flagp |= HASWIDTH|SIMPLE;
-           goto finish_meta_pat;
-       case 'V':
-           ret = reg_node(pRExC_state, NVERTWS);
-           *flagp |= HASWIDTH|SIMPLE;
-         finish_meta_pat:          
-           nextchar(pRExC_state);
-            Set_Node_Length(ret, 2); /* MJD */
-           break;          
-       case 'p':
-       case 'P':
-           {   
-               char* const oldregxend = RExC_end;
-#ifdef DEBUGGING
-               char* parse_start = RExC_parse - 2;
-#endif
-
-               if (RExC_parse[1] == '{') {
-                 /* a lovely hack--pretend we saw [\pX] instead */
-                   RExC_end = strchr(RExC_parse, '}');
-                   if (!RExC_end) {
-                       const U8 c = (U8)*RExC_parse;
-                       RExC_parse += 2;
-                       RExC_end = oldregxend;
-                       vFAIL2("Missing right brace on \\%c{}", c);
-                   }
-                   RExC_end++;
-               }
-               else {
-                   RExC_end = RExC_parse + 2;
-                   if (RExC_end > oldregxend)
-                       RExC_end = oldregxend;
-               }
-               RExC_parse--;
-
-                ret = regclass(pRExC_state,depth+1);
-
-               RExC_end = oldregxend;
-               RExC_parse--;
-
-               Set_Node_Offset(ret, parse_start + 2);
-               Set_Node_Cur_Length(ret);
-               nextchar(pRExC_state);
-               *flagp |= HASWIDTH|SIMPLE;
-           }
-           break;
-        case 'N': 
-            /* Handle \N and \N{NAME} here and not below because it can be
-            multicharacter. join_exact() will join them up later on. 
-            Also this makes sure that things like /\N{BLAH}+/ and 
-            \N{BLAH} being multi char Just Happen. dmq*/
-            ++RExC_parse;
-            ret= reg_namedseq(pRExC_state, NULL, flagp); 
-            break;
-       case 'k':    /* Handle \k<NAME> and \k'NAME' */
-       parse_named_seq:
-        {   
-            char ch= RExC_parse[1];        
-           if (ch != '<' && ch != '\'' && ch != '{') {
-               RExC_parse++;
-               vFAIL2("Sequence %.2s... not terminated",parse_start);
-           } else {
-               /* this pretty much dupes the code for (?P=...) in reg(), if
-                   you change this make sure you change that */
-               char* name_start = (RExC_parse += 2);
-               U32 num = 0;
-                SV *sv_dat = reg_scan_name(pRExC_state,
-                    SIZE_ONLY ? REG_RSN_RETURN_NULL : REG_RSN_RETURN_DATA);
-                ch= (ch == '<') ? '>' : (ch == '{') ? '}' : '\'';
-                if (RExC_parse == name_start || *RExC_parse != ch)
-                    vFAIL2("Sequence %.3s... not terminated",parse_start);
-
-                if (!SIZE_ONLY) {
-                    num = add_data( pRExC_state, 1, "S" );
-                    RExC_rxi->data->data[num]=(void*)sv_dat;
-                    SvREFCNT_inc_simple_void(sv_dat);
-                }
-
-                RExC_sawback = 1;
-                ret = reganode(pRExC_state,
-                               ((! FOLD)
-                                 ? NREF
-                                 : (AT_LEAST_UNI_SEMANTICS)
-                                   ? NREFFU
-                                   : (LOC)
-                                     ? NREFFL
-                                     : NREFF),
-                                num);
-                *flagp |= HASWIDTH;
-
-                /* override incorrect value set in reganode MJD */
-                Set_Node_Offset(ret, parse_start+1);
-                Set_Node_Cur_Length(ret); /* MJD */
-                nextchar(pRExC_state);
-
-            }
-            break;
-       }
-       case 'g': 
-       case '1': case '2': case '3': case '4':
-       case '5': case '6': case '7': case '8': case '9':
-           {
-               I32 num;
-               bool isg = *RExC_parse == 'g';
-               bool isrel = 0; 
-               bool hasbrace = 0;
-               if (isg) {
-                   RExC_parse++;
-                   if (*RExC_parse == '{') {
-                       RExC_parse++;
-                       hasbrace = 1;
-                   }
-                   if (*RExC_parse == '-') {
-                       RExC_parse++;
-                       isrel = 1;
-                   }
-                   if (hasbrace && !isDIGIT(*RExC_parse)) {
-                       if (isrel) RExC_parse--;
-                        RExC_parse -= 2;                           
-                       goto parse_named_seq;
-               }   }
-               num = atoi(RExC_parse);
-               if (isg && num == 0)
-                   vFAIL("Reference to invalid group 0");
-                if (isrel) {
-                    num = RExC_npar - num;
-                    if (num < 1)
-                        vFAIL("Reference to nonexistent or unclosed group");
-                }
-               if (!isg && num > 9 && num >= RExC_npar)
-                   goto defchar;
-               else {
-                   char * const parse_start = RExC_parse - 1; /* MJD */
-                   while (isDIGIT(*RExC_parse))
-                       RExC_parse++;
-                   if (parse_start == RExC_parse - 1) 
-                       vFAIL("Unterminated \\g... pattern");
-                    if (hasbrace) {
-                        if (*RExC_parse != '}') 
-                            vFAIL("Unterminated \\g{...} pattern");
-                        RExC_parse++;
-                    }    
-                   if (!SIZE_ONLY) {
-                       if (num > (I32)RExC_rx->nparens)
-                           vFAIL("Reference to nonexistent group");
-                   }
-                   RExC_sawback = 1;
-                   ret = reganode(pRExC_state,
-                                  ((! FOLD)
-                                    ? REF
-                                    : (AT_LEAST_UNI_SEMANTICS)
-                                      ? REFFU
-                                      : (LOC)
-                                        ? REFFL
-                                        : REFF),
-                                   num);
-                   *flagp |= HASWIDTH;
-
-                    /* override incorrect value set in reganode MJD */
-                    Set_Node_Offset(ret, parse_start+1);
-                    Set_Node_Cur_Length(ret); /* MJD */
-                   RExC_parse--;
-                   nextchar(pRExC_state);
-               }
-           }
-           break;
-       case '\0':
-           if (RExC_parse >= RExC_end)
-               FAIL("Trailing \\");
-           /* FALL THROUGH */
-       default:
-           /* Do not generate "unrecognized" warnings here, we fall
-              back into the quick-grab loop below */
-           parse_start--;
-           goto defchar;
-       }
-       break;
-
-    case '#':
-       if (RExC_flags & RXf_PMf_EXTENDED) {
-           if ( reg_skipcomment( pRExC_state ) )
-               goto tryagain;
-       }
-       /* FALL THROUGH */
-
-    default:
-        outer_default:{
-           register STRLEN len;
-           register UV ender;
-           register char *p;
-           char *s;
-           STRLEN foldlen;
-           U8 tmpbuf[UTF8_MAXBYTES_CASE+1], *foldbuf;
-
-            parse_start = RExC_parse - 1;
-
-           RExC_parse++;
-
-       defchar:
-           ender = 0;
-           ret = reg_node(pRExC_state,
-                          (U8) ((! FOLD) ? EXACT
-                                         : (LOC)
-                                            ? EXACTFL
-                                            : (AT_LEAST_UNI_SEMANTICS)
-                                              ? EXACTFU
-                                              : EXACTF)
-                   );
-           s = STRING(ret);
-           for (len = 0, p = RExC_parse - 1;
-             len < 127 && p < RExC_end;
-             len++)
-           {
-               char * const oldp = p;
-
-               if (RExC_flags & RXf_PMf_EXTENDED)
-                   p = regwhite( pRExC_state, p );
-               switch ((U8)*p) {
-               case LATIN_SMALL_LETTER_SHARP_S:
-               case UTF8_TWO_BYTE_HI_nocast(LATIN_SMALL_LETTER_SHARP_S):
-               case UTF8_TWO_BYTE_HI_nocast(IOTA_D_T):
-                          if (LOC || !FOLD || !is_TRICKYFOLD_safe(p,RExC_end,UTF))
-                               goto normal_default;
-               case '^':
-               case '$':
-               case '.':
-               case '[':
-               case '(':
-               case ')':
-               case '|':
-                   goto loopdone;
-               case '\\':
-                   /* Literal Escapes Switch
-
-                      This switch is meant to handle escape sequences that
-                      resolve to a literal character.
-
-                      Every escape sequence that represents something
-                      else, like an assertion or a char class, is handled
-                      in the switch marked 'Special Escapes' above in this
-                      routine, but also has an entry here as anything that
-                      isn't explicitly mentioned here will be treated as
-                      an unescaped equivalent literal.
-                   */
-
-                   switch ((U8)*++p) {
-                   /* These are all the special escapes. */
-                    case LATIN_SMALL_LETTER_SHARP_S:
-                    case UTF8_TWO_BYTE_HI_nocast(LATIN_SMALL_LETTER_SHARP_S):
-                    case UTF8_TWO_BYTE_HI_nocast(IOTA_D_T):
-                          if (LOC || !FOLD || !is_TRICKYFOLD_safe(p,RExC_end,UTF))
-                               goto normal_default;                
-                   case 'A':             /* Start assertion */
-                   case 'b': case 'B':   /* Word-boundary assertion*/
-                   case 'C':             /* Single char !DANGEROUS! */
-                   case 'd': case 'D':   /* digit class */
-                   case 'g': case 'G':   /* generic-backref, pos assertion */
-                   case 'h': case 'H':   /* HORIZWS */
-                   case 'k': case 'K':   /* named backref, keep marker */
-                   case 'N':             /* named char sequence */
-                   case 'p': case 'P':   /* Unicode property */
-                             case 'R':   /* LNBREAK */
-                   case 's': case 'S':   /* space class */
-                   case 'v': case 'V':   /* VERTWS */
-                   case 'w': case 'W':   /* word class */
-                   case 'X':             /* eXtended Unicode "combining character sequence" */
-                   case 'z': case 'Z':   /* End of line/string assertion */
-                       --p;
-                       goto loopdone;
-
-                   /* Anything after here is an escape that resolves to a
-                      literal. (Except digits, which may or may not)
-                    */
-                   case 'n':
-                       ender = '\n';
-                       p++;
-                       break;
-                   case 'r':
-                       ender = '\r';
-                       p++;
-                       break;
-                   case 't':
-                       ender = '\t';
-                       p++;
-                       break;
-                   case 'f':
-                       ender = '\f';
-                       p++;
-                       break;
-                   case 'e':
-                         ender = ASCII_TO_NATIVE('\033');
-                       p++;
-                       break;
-                   case 'a':
-                         ender = ASCII_TO_NATIVE('\007');
-                       p++;
-                       break;
-                   case 'o':
-                       {
-                           STRLEN brace_len = len;
-                           UV result;
-                           const char* error_msg;
-
-                           bool valid = grok_bslash_o(p,
-                                                      &result,
-                                                      &brace_len,
-                                                      &error_msg,
-                                                      1);
-                           p += brace_len;
-                           if (! valid) {
-                               RExC_parse = p; /* going to die anyway; point
-                                                  to exact spot of failure */
-                               vFAIL(error_msg);
-                           }
-                           else
-                           {
-                               ender = result;
-                           }
-                           if (PL_encoding && ender < 0x100) {
-                               goto recode_encoding;
-                           }
-                           if (ender > 0xff) {
-                               REQUIRE_UTF8;
-                           }
-                           break;
-                       }
-                   case 'x':
-                       if (*++p == '{') {
-                           char* const e = strchr(p, '}');
-       
-                           if (!e) {
-                               RExC_parse = p + 1;
-                               vFAIL("Missing right brace on \\x{}");
-                           }
-                           else {
-                                I32 flags = PERL_SCAN_ALLOW_UNDERSCORES
-                                    | PERL_SCAN_DISALLOW_PREFIX;
-                                STRLEN numlen = e - p - 1;
-                               ender = grok_hex(p + 1, &numlen, &flags, NULL);
-                               if (ender > 0xff)
-                                   REQUIRE_UTF8;
-                               p = e + 1;
-                           }
-                       }
-                       else {
-                            I32 flags = PERL_SCAN_DISALLOW_PREFIX;
-                           STRLEN numlen = 2;
-                           ender = grok_hex(p, &numlen, &flags, NULL);
-                           p += numlen;
-                       }
-                       if (PL_encoding && ender < 0x100)
-                           goto recode_encoding;
-                       break;
-                   case 'c':
-                       p++;
-                       ender = grok_bslash_c(*p++, SIZE_ONLY);
-                       break;
-                   case '0': case '1': case '2': case '3':case '4':
-                   case '5': case '6': case '7': case '8':case '9':
-                       if (*p == '0' ||
-                           (isDIGIT(p[1]) && atoi(p) >= RExC_npar))
-                       {
-                           I32 flags = PERL_SCAN_SILENT_ILLDIGIT;
-                           STRLEN numlen = 3;
-                           ender = grok_oct(p, &numlen, &flags, NULL);
-                           if (ender > 0xff) {
-                               REQUIRE_UTF8;
-                           }
-                           p += numlen;
-                       }
-                       else {
-                           --p;
-                           goto loopdone;
-                       }
-                       if (PL_encoding && ender < 0x100)
-                           goto recode_encoding;
-                       break;
-                   recode_encoding:
-                       {
-                           SV* enc = PL_encoding;
-                           ender = reg_recode((const char)(U8)ender, &enc);
-                           if (!enc && SIZE_ONLY)
-                               ckWARNreg(p, "Invalid escape in the specified encoding");
-                           REQUIRE_UTF8;
-                       }
-                       break;
-                   case '\0':
-                       if (p >= RExC_end)
-                           FAIL("Trailing \\");
-                       /* FALL THROUGH */
-                   default:
-                       if (!SIZE_ONLY&& isALPHA(*p))
-                           ckWARN2reg(p + 1, "Unrecognized escape \\%c passed through", UCHARAT(p));
-                       goto normal_default;
-                   }
-                   break;
-               default:
-                 normal_default:
-                   if (UTF8_IS_START(*p) && UTF) {
-                       STRLEN numlen;
-                       ender = utf8n_to_uvchr((U8*)p, RExC_end - p,
-                                              &numlen, UTF8_ALLOW_DEFAULT);
-                       p += numlen;
-                   }
-                   else
-                       ender = *p++;
-                   break;
-               }
-               if ( RExC_flags & RXf_PMf_EXTENDED)
-                   p = regwhite( pRExC_state, p );
-               if (UTF && FOLD) {
-                   /* Prime the casefolded buffer. */
-                   ender = toFOLD_uni(ender, tmpbuf, &foldlen);
-               }
-               if (p < RExC_end && ISMULT2(p)) { /* Back off on ?+*. */
-                   if (len)
-                       p = oldp;
-                   else if (UTF) {
-                        if (FOLD) {
-                             /* Emit all the Unicode characters. */
-                             STRLEN numlen;
-                             for (foldbuf = tmpbuf;
-                                  foldlen;
-                                  foldlen -= numlen) {
-                                  ender = utf8_to_uvchr(foldbuf, &numlen);
-                                  if (numlen > 0) {
-                                       const STRLEN unilen = reguni(pRExC_state, ender, s);
-                                       s       += unilen;
-                                       len     += unilen;
-                                       /* In EBCDIC the numlen
-                                        * and unilen can differ. */
-                                       foldbuf += numlen;
-                                       if (numlen >= foldlen)
-                                            break;
-                                  }
-                                  else
-                                       break; /* "Can't happen." */
-                             }
-                        }
-                        else {
-                             const STRLEN unilen = reguni(pRExC_state, ender, s);
-                             if (unilen > 0) {
-                                  s   += unilen;
-                                  len += unilen;
-                             }
-                        }
-                   }
-                   else {
-                       len++;
-                       REGC((char)ender, s++);
-                   }
-                   break;
-               }
-               if (UTF) {
-                    if (FOLD) {
-                         /* Emit all the Unicode characters. */
-                         STRLEN numlen;
-                         for (foldbuf = tmpbuf;
-                              foldlen;
-                              foldlen -= numlen) {
-                              ender = utf8_to_uvchr(foldbuf, &numlen);
-                              if (numlen > 0) {
-                                   const STRLEN unilen = reguni(pRExC_state, ender, s);
-                                   len     += unilen;
-                                   s       += unilen;
-                                   /* In EBCDIC the numlen
-                                    * and unilen can differ. */
-                                   foldbuf += numlen;
-                                   if (numlen >= foldlen)
-                                        break;
-                              }
-                              else
-                                   break;
-                         }
-                    }
-                    else {
-                         const STRLEN unilen = reguni(pRExC_state, ender, s);
-                         if (unilen > 0) {
-                              s   += unilen;
-                              len += unilen;
-                         }
-                    }
-                    len--;
-               }
-               else
-                   REGC((char)ender, s++);
-           }
-       loopdone:
-           RExC_parse = p - 1;
-            Set_Node_Cur_Length(ret); /* MJD */
-           nextchar(pRExC_state);
-           {
-               /* len is STRLEN which is unsigned, need to copy to signed */
-               IV iv = len;
-               if (iv < 0)
-                   vFAIL("Internal disaster");
-           }
-           if (len > 0)
-               *flagp |= HASWIDTH;
-           if (len == 1 && UNI_IS_INVARIANT(ender))
-               *flagp |= SIMPLE;
-               
-           if (SIZE_ONLY)
-               RExC_size += STR_SZ(len);
-           else {
-               STR_LEN(ret) = len;
-               RExC_emit += STR_SZ(len);
-            }
-       }
-       break;
-    }
-
-    return(ret);
-
-/* Jumped to when an unrecognized character set is encountered */
-bad_charset:
-    Perl_croak(aTHX_ "panic: Unknown regex character set encoding: %u", get_regex_charset(RExC_flags));
-    return(NULL);
-}
-
-STATIC char *
-S_regwhite( RExC_state_t *pRExC_state, char *p )
-{
-    const char *e = RExC_end;
-
-    PERL_ARGS_ASSERT_REGWHITE;
-
-    while (p < e) {
-       if (isSPACE(*p))
-           ++p;
-       else if (*p == '#') {
-            bool ended = 0;
-           do {
-               if (*p++ == '\n') {
-                   ended = 1;
-                   break;
-               }
-           } while (p < e);
-           if (!ended)
-               RExC_seen |= REG_SEEN_RUN_ON_COMMENT;
-       }
-       else
-           break;
-    }
-    return p;
-}
-
-/* Parse POSIX character classes: [[:foo:]], [[=foo=]], [[.foo.]].
-   Character classes ([:foo:]) can also be negated ([:^foo:]).
-   Returns a named class id (ANYOF_XXX) if successful, -1 otherwise.
-   Equivalence classes ([=foo=]) and composites ([.foo.]) are parsed,
-   but trigger failures because they are currently unimplemented. */
-
-#define POSIXCC_DONE(c)   ((c) == ':')
-#define POSIXCC_NOTYET(c) ((c) == '=' || (c) == '.')
-#define POSIXCC(c) (POSIXCC_DONE(c) || POSIXCC_NOTYET(c))
-
-STATIC I32
-S_regpposixcc(pTHX_ RExC_state_t *pRExC_state, I32 value)
-{
-    dVAR;
-    I32 namedclass = OOB_NAMEDCLASS;
-
-    PERL_ARGS_ASSERT_REGPPOSIXCC;
-
-    if (value == '[' && RExC_parse + 1 < RExC_end &&
-       /* I smell either [: or [= or [. -- POSIX has been here, right? */
-       POSIXCC(UCHARAT(RExC_parse))) {
-       const char c = UCHARAT(RExC_parse);
-       char* const s = RExC_parse++;
-       
-       while (RExC_parse < RExC_end && UCHARAT(RExC_parse) != c)
-           RExC_parse++;
-       if (RExC_parse == RExC_end)
-           /* Grandfather lone [:, [=, [. */
-           RExC_parse = s;
-       else {
-           const char* const t = RExC_parse++; /* skip over the c */
-           assert(*t == c);
-
-           if (UCHARAT(RExC_parse) == ']') {
-               const char *posixcc = s + 1;
-               RExC_parse++; /* skip over the ending ] */
-
-               if (*s == ':') {
-                   const I32 complement = *posixcc == '^' ? *posixcc++ : 0;
-                   const I32 skip = t - posixcc;
-
-                   /* Initially switch on the length of the name.  */
-                   switch (skip) {
-                   case 4:
-                       if (memEQ(posixcc, "word", 4)) /* this is not POSIX, this is the Perl \w */
-                           namedclass = complement ? ANYOF_NALNUM : ANYOF_ALNUM;
-                       break;
-                   case 5:
-                       /* Names all of length 5.  */
-                       /* alnum alpha ascii blank cntrl digit graph lower
-                          print punct space upper  */
-                       /* Offset 4 gives the best switch position.  */
-                       switch (posixcc[4]) {
-                       case 'a':
-                           if (memEQ(posixcc, "alph", 4)) /* alpha */
-                               namedclass = complement ? ANYOF_NALPHA : ANYOF_ALPHA;
-                           break;
-                       case 'e':
-                           if (memEQ(posixcc, "spac", 4)) /* space */
-                               namedclass = complement ? ANYOF_NPSXSPC : ANYOF_PSXSPC;
-                           break;
-                       case 'h':
-                           if (memEQ(posixcc, "grap", 4)) /* graph */
-                               namedclass = complement ? ANYOF_NGRAPH : ANYOF_GRAPH;
-                           break;
-                       case 'i':
-                           if (memEQ(posixcc, "asci", 4)) /* ascii */
-                               namedclass = complement ? ANYOF_NASCII : ANYOF_ASCII;
-                           break;
-                       case 'k':
-                           if (memEQ(posixcc, "blan", 4)) /* blank */
-                               namedclass = complement ? ANYOF_NBLANK : ANYOF_BLANK;
-                           break;
-                       case 'l':
-                           if (memEQ(posixcc, "cntr", 4)) /* cntrl */
-                               namedclass = complement ? ANYOF_NCNTRL : ANYOF_CNTRL;
-                           break;
-                       case 'm':
-                           if (memEQ(posixcc, "alnu", 4)) /* alnum */
-                               namedclass = complement ? ANYOF_NALNUMC : ANYOF_ALNUMC;
-                           break;
-                       case 'r':
-                           if (memEQ(posixcc, "lowe", 4)) /* lower */
-                               namedclass = complement ? ANYOF_NLOWER : ANYOF_LOWER;
-                           else if (memEQ(posixcc, "uppe", 4)) /* upper */
-                               namedclass = complement ? ANYOF_NUPPER : ANYOF_UPPER;
-                           break;
-                       case 't':
-                           if (memEQ(posixcc, "digi", 4)) /* digit */
-                               namedclass = complement ? ANYOF_NDIGIT : ANYOF_DIGIT;
-                           else if (memEQ(posixcc, "prin", 4)) /* print */
-                               namedclass = complement ? ANYOF_NPRINT : ANYOF_PRINT;
-                           else if (memEQ(posixcc, "punc", 4)) /* punct */
-                               namedclass = complement ? ANYOF_NPUNCT : ANYOF_PUNCT;
-                           break;
-                       }
-                       break;
-                   case 6:
-                       if (memEQ(posixcc, "xdigit", 6))
-                           namedclass = complement ? ANYOF_NXDIGIT : ANYOF_XDIGIT;
-                       break;
-                   }
-
-                   if (namedclass == OOB_NAMEDCLASS)
-                       Simple_vFAIL3("POSIX class [:%.*s:] unknown",
-                                     t - s - 1, s + 1);
-                   assert (posixcc[skip] == ':');
-                   assert (posixcc[skip+1] == ']');
-               } else if (!SIZE_ONLY) {
-                   /* [[=foo=]] and [[.foo.]] are still future. */
-
-                   /* adjust RExC_parse so the warning shows after
-                      the class closes */
-                   while (UCHARAT(RExC_parse) && UCHARAT(RExC_parse) != ']')
-                       RExC_parse++;
-                   Simple_vFAIL3("POSIX syntax [%c %c] is reserved for future extensions", c, c);
-               }
-           } else {
-               /* Maternal grandfather:
-                * "[:" ending in ":" but not in ":]" */
-               RExC_parse = s;
-           }
-       }
-    }
-
-    return namedclass;
-}
-
-STATIC void
-S_checkposixcc(pTHX_ RExC_state_t *pRExC_state)
-{
-    dVAR;
-
-    PERL_ARGS_ASSERT_CHECKPOSIXCC;
-
-    if (POSIXCC(UCHARAT(RExC_parse))) {
-       const char *s = RExC_parse;
-       const char  c = *s++;
-
-       while (isALNUM(*s))
-           s++;
-       if (*s && c == *s && s[1] == ']') {
-           ckWARN3reg(s+2,
-                      "POSIX syntax [%c %c] belongs inside character classes",
-                      c, c);
-
-           /* [[=foo=]] and [[.foo.]] are still future. */
-           if (POSIXCC_NOTYET(c)) {
-               /* adjust RExC_parse so the error shows after
-                  the class closes */
-               while (UCHARAT(RExC_parse) && UCHARAT(RExC_parse++) != ']')
-                   NOOP;
-               Simple_vFAIL3("POSIX syntax [%c %c] is reserved for future extensions", c, c);
-           }
-       }
-    }
-}
-
-/* No locale test, and always Unicode semantics */
-#define _C_C_T_NOLOC_(NAME,TEST,WORD)                                          \
-ANYOF_##NAME:                                                                  \
-       for (value = 0; value < 256; value++)                                  \
-           if (TEST)                                                          \
-           stored += S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) value);  \
-    yesno = '+';                                                               \
-    what = WORD;                                                               \
-    break;                                                                     \
-case ANYOF_N##NAME:                                                            \
-       for (value = 0; value < 256; value++)                                  \
-           if (!TEST)                                                         \
-           stored += S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) value);  \
-    yesno = '!';                                                               \
-    what = WORD;                                                               \
-    break
-
-/* Like the above, but there are differences if we are in uni-8-bit or not, so
- * there are two tests passed in, to use depending on that. There aren't any
- * cases where the label is different from the name, so no need for that
- * parameter */
-#define _C_C_T_(NAME,TEST_8,TEST_7,WORD)                                       \
-ANYOF_##NAME:                                                                  \
-    if (LOC) ANYOF_CLASS_SET(ret, ANYOF_##NAME);                               \
-    else if (UNI_SEMANTICS) {                                                  \
-        for (value = 0; value < 256; value++) {                                \
-            if (TEST_8) stored +=                                              \
-                      S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) value);  \
-        }                                                                      \
-    }                                                                          \
-    else {                                                                     \
-        for (value = 0; value < 128; value++) {                                \
-            if (TEST_7) stored +=                                              \
-               S_set_regclass_bit(aTHX_ pRExC_state, ret,                     \
-                                  (U8) UNI_TO_NATIVE(value));                 \
-        }                                                                      \
-    }                                                                          \
-    yesno = '+';                                                               \
-    what = WORD;                                                               \
-    break;                                                                     \
-case ANYOF_N##NAME:                                                            \
-    if (LOC) ANYOF_CLASS_SET(ret, ANYOF_N##NAME);                              \
-    else if (UNI_SEMANTICS) {                                                  \
-        for (value = 0; value < 256; value++) {                                \
-            if (! TEST_8) stored +=                                            \
-                   S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) value);    \
-        }                                                                      \
-    }                                                                          \
-    else {                                                                     \
-        for (value = 0; value < 128; value++) {                                \
-            if (! TEST_7) stored +=                                            \
-                   S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) value);    \
-        }                                                                      \
-       if (ASCII_RESTRICTED) {                                                \
-           for (value = 128; value < 256; value++) {                          \
-             stored += S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) value); \
-           }                                                                  \
-           ANYOF_FLAGS(ret) |= ANYOF_UNICODE_ALL|ANYOF_UTF8;                  \
-       }                                                                      \
-       else {                                                                 \
-           /* For a non-ut8 target string with DEPENDS semantics, all above   \
-            * ASCII Latin1 code points match the complement of any of the     \
-            * classes.  But in utf8, they have their Unicode semantics, so    \
-            * can't just set them in the bitmap, or else regexec.c will think \
-            * they matched when they shouldn't. */                            \
-           ANYOF_FLAGS(ret) |= ANYOF_NON_UTF8_LATIN1_ALL|ANYOF_UTF8;          \
-       }                                                                      \
-    }                                                                          \
-    yesno = '!';                                                               \
-    what = WORD;                                                               \
-    break
-
-/* 
-   We dont use PERL_LEGACY_UNICODE_CHARCLASS_MAPPINGS as the direct test
-   so that it is possible to override the option here without having to 
-   rebuild the entire core. as we are required to do if we change regcomp.h
-   which is where PERL_LEGACY_UNICODE_CHARCLASS_MAPPINGS is defined.
-*/
-#if PERL_LEGACY_UNICODE_CHARCLASS_MAPPINGS
-#define BROKEN_UNICODE_CHARCLASS_MAPPINGS
-#endif
-
-#ifdef BROKEN_UNICODE_CHARCLASS_MAPPINGS
-#define POSIX_CC_UNI_NAME(CCNAME) CCNAME
-#else
-#define POSIX_CC_UNI_NAME(CCNAME) "Posix" CCNAME
-#endif
-
-STATIC U8
-S_set_regclass_bit_fold(pTHX_ RExC_state_t *pRExC_state, regnode* node, const U8 value)
-{
-
-    /* Handle the setting of folds in the bitmap for non-locale ANYOF nodes.
-     * Locale folding is done at run-time, so this function should not be
-     * called for nodes that are for locales.
-     *
-     * This function simply sets the bit corresponding to the fold of the input
-     * 'value', if not already set.  The fold of 'f' is 'F', and the fold of
-     * 'F' is 'f'.
-     *
-     * It also sets any necessary flags, and returns the number of bits that
-     * actually changed from 0 to 1 */
-
-    U8 stored = 0;
-    U8 fold;
-
-    fold = (AT_LEAST_UNI_SEMANTICS) ? PL_fold_latin1[value]
-                           : PL_fold[value];
-
-    /* It assumes the bit for 'value' has already been set */
-    if (fold != value && ! ANYOF_BITMAP_TEST(node, fold)) {
-        ANYOF_BITMAP_SET(node, fold);
-        stored++;
-    }
-    if (_HAS_NONLATIN1_FOLD_CLOSURE_ONLY_FOR_USE_BY_REGCOMP_DOT_C_AND_REGEXEC_DOT_C(value)
-       || (! UNI_SEMANTICS
-           && ! isASCII(value)
-           && PL_fold_latin1[value] != value))
-    {   /* A character that has a fold outside of Latin1 matches outside the
-           bitmap, but only when the target string is utf8.  Similarly when we
-           don't have unicode semantics for the above ASCII Latin-1 characters,
-           and they have a fold, they should match if the target is utf8, and
-           not otherwise */
-       ANYOF_FLAGS(node) |= ANYOF_UTF8;
-    }
-
-    return stored;
-}
-
-
-PERL_STATIC_INLINE U8
-S_set_regclass_bit(pTHX_ RExC_state_t *pRExC_state, regnode* node, const U8 value)
-{
-    /* This inline function sets a bit in the bitmap if not already set, and if
-     * appropriate, its fold, returning the number of bits that actually
-     * changed from 0 to 1 */
-
-    U8 stored;
-
-    if (ANYOF_BITMAP_TEST(node, value)) {   /* Already set */
-       return 0;
-    }
-
-    ANYOF_BITMAP_SET(node, value);
-    stored = 1;
-
-    if (FOLD && ! LOC) {       /* Locale folds aren't known until runtime */
-       stored += S_set_regclass_bit_fold(aTHX_ pRExC_state, node, value);
-    }
-
-    return stored;
-}
-
-/*
-   parse a class specification and produce either an ANYOF node that
-   matches the pattern or if the pattern matches a single char only and
-   that char is < 256 and we are case insensitive then we produce an 
-   EXACT node instead.
-*/
-
-STATIC regnode *
-S_regclass(pTHX_ RExC_state_t *pRExC_state, U32 depth)
-{
-    dVAR;
-    register UV nextvalue;
-    register IV prevvalue = OOB_UNICODE;
-    register IV range = 0;
-    UV value = 0; /* XXX:dmq: needs to be referenceable (unfortunately) */
-    register regnode *ret;
-    STRLEN numlen;
-    IV namedclass;
-    char *rangebegin = NULL;
-    bool need_class = 0;
-    SV *listsv = NULL;
-    UV n;
-    AV* unicode_alternate  = NULL;
-#ifdef EBCDIC
-    UV literal_endpoint = 0;
-#endif
-    UV stored = 0;  /* how many chars stored in the bitmap */
-
-    regnode * const orig_emit = RExC_emit; /* Save the original RExC_emit in
-        case we need to change the emitted regop to an EXACT. */
-    const char * orig_parse = RExC_parse;
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_REGCLASS;
-#ifndef DEBUGGING
-    PERL_UNUSED_ARG(depth);
-#endif
-
-    DEBUG_PARSE("clas");
-
-    /* Assume we are going to generate an ANYOF node. */
-    ret = reganode(pRExC_state, ANYOF, 0);
-
-    if (!SIZE_ONLY)
-       ANYOF_FLAGS(ret) = 0;
-
-    if (UCHARAT(RExC_parse) == '^') {  /* Complement of range. */
-       RExC_naughty++;
-       RExC_parse++;
-       if (!SIZE_ONLY)
-           ANYOF_FLAGS(ret) |= ANYOF_INVERT;
-    }
-
-    if (SIZE_ONLY) {
-       RExC_size += ANYOF_SKIP;
-#ifdef ANYOF_ADD_LOC_SKIP
-       if (LOC) {
-           RExC_size += ANYOF_ADD_LOC_SKIP;
-       }
-#endif
-       listsv = &PL_sv_undef; /* For code scanners: listsv always non-NULL. */
-    }
-    else {
-       RExC_emit += ANYOF_SKIP;
-       if (LOC) {
-           ANYOF_FLAGS(ret) |= ANYOF_LOCALE;
-#ifdef ANYOF_ADD_LOC_SKIP
-           RExC_emit += ANYOF_ADD_LOC_SKIP;
-#endif
-       }
-       ANYOF_BITMAP_ZERO(ret);
-       listsv = newSVpvs("# comment\n");
-    }
-
-    nextvalue = RExC_parse < RExC_end ? UCHARAT(RExC_parse) : 0;
-
-    if (!SIZE_ONLY && POSIXCC(nextvalue))
-       checkposixcc(pRExC_state);
-
-    /* allow 1st char to be ] (allowing it to be - is dealt with later) */
-    if (UCHARAT(RExC_parse) == ']')
-       goto charclassloop;
-
-parseit:
-    while (RExC_parse < RExC_end && UCHARAT(RExC_parse) != ']') {
-
-    charclassloop:
-
-       namedclass = OOB_NAMEDCLASS; /* initialize as illegal */
-
-       if (!range)
-           rangebegin = RExC_parse;
-       if (UTF) {
-           value = utf8n_to_uvchr((U8*)RExC_parse,
-                                  RExC_end - RExC_parse,
-                                  &numlen, UTF8_ALLOW_DEFAULT);
-           RExC_parse += numlen;
-       }
-       else
-           value = UCHARAT(RExC_parse++);
-
-       nextvalue = RExC_parse < RExC_end ? UCHARAT(RExC_parse) : 0;
-       if (value == '[' && POSIXCC(nextvalue))
-           namedclass = regpposixcc(pRExC_state, value);
-       else if (value == '\\') {
-           if (UTF) {
-               value = utf8n_to_uvchr((U8*)RExC_parse,
-                                  RExC_end - RExC_parse,
-                                  &numlen, UTF8_ALLOW_DEFAULT);
-               RExC_parse += numlen;
-           }
-           else
-               value = UCHARAT(RExC_parse++);
-           /* Some compilers cannot handle switching on 64-bit integer
-            * values, therefore value cannot be an UV.  Yes, this will
-            * be a problem later if we want switch on Unicode.
-            * A similar issue a little bit later when switching on
-            * namedclass. --jhi */
-           switch ((I32)value) {
-           case 'w':   namedclass = ANYOF_ALNUM;       break;
-           case 'W':   namedclass = ANYOF_NALNUM;      break;
-           case 's':   namedclass = ANYOF_SPACE;       break;
-           case 'S':   namedclass = ANYOF_NSPACE;      break;
-           case 'd':   namedclass = ANYOF_DIGIT;       break;
-           case 'D':   namedclass = ANYOF_NDIGIT;      break;
-           case 'v':   namedclass = ANYOF_VERTWS;      break;
-           case 'V':   namedclass = ANYOF_NVERTWS;     break;
-           case 'h':   namedclass = ANYOF_HORIZWS;     break;
-           case 'H':   namedclass = ANYOF_NHORIZWS;    break;
-            case 'N':  /* Handle \N{NAME} in class */
-                {
-                    /* We only pay attention to the first char of 
-                    multichar strings being returned. I kinda wonder
-                    if this makes sense as it does change the behaviour
-                    from earlier versions, OTOH that behaviour was broken
-                    as well. */
-                    UV v; /* value is register so we cant & it /grrr */
-                    if (reg_namedseq(pRExC_state, &v, NULL)) {
-                        goto parseit;
-                    }
-                    value= v; 
-                }
-                break;
-           case 'p':
-           case 'P':
-               {
-               char *e;
-               if (RExC_parse >= RExC_end)
-                   vFAIL2("Empty \\%c{}", (U8)value);
-               if (*RExC_parse == '{') {
-                   const U8 c = (U8)value;
-                   e = strchr(RExC_parse++, '}');
-                    if (!e)
-                        vFAIL2("Missing right brace on \\%c{}", c);
-                   while (isSPACE(UCHARAT(RExC_parse)))
-                       RExC_parse++;
-                    if (e == RExC_parse)
-                        vFAIL2("Empty \\%c{}", c);
-                   n = e - RExC_parse;
-                   while (isSPACE(UCHARAT(RExC_parse + n - 1)))
-                       n--;
-               }
-               else {
-                   e = RExC_parse;
-                   n = 1;
-               }
-               if (!SIZE_ONLY) {
-                   if (UCHARAT(RExC_parse) == '^') {
-                        RExC_parse++;
-                        n--;
-                        value = value == 'p' ? 'P' : 'p'; /* toggle */
-                        while (isSPACE(UCHARAT(RExC_parse))) {
-                             RExC_parse++;
-                             n--;
-                        }
-                   }
-                   Perl_sv_catpvf(aTHX_ listsv, "%cutf8::%.*s\n",
-                       (value=='p' ? '+' : '!'), (int)n, RExC_parse);
-               }
-               RExC_parse = e + 1;
-
-               /* The \p could match something in the Latin1 range, hence
-                * something that isn't utf8 */
-               ANYOF_FLAGS(ret) |= ANYOF_NONBITMAP;
-               namedclass = ANYOF_MAX;  /* no official name, but it's named */
-               }
-               break;
-           case 'n':   value = '\n';                   break;
-           case 'r':   value = '\r';                   break;
-           case 't':   value = '\t';                   break;
-           case 'f':   value = '\f';                   break;
-           case 'b':   value = '\b';                   break;
-           case 'e':   value = ASCII_TO_NATIVE('\033');break;
-           case 'a':   value = ASCII_TO_NATIVE('\007');break;
-           case 'o':
-               RExC_parse--;   /* function expects to be pointed at the 'o' */
-               {
-                   const char* error_msg;
-                   bool valid = grok_bslash_o(RExC_parse,
-                                              &value,
-                                              &numlen,
-                                              &error_msg,
-                                              SIZE_ONLY);
-                   RExC_parse += numlen;
-                   if (! valid) {
-                       vFAIL(error_msg);
-                   }
-               }
-               if (PL_encoding && value < 0x100) {
-                   goto recode_encoding;
-               }
-               break;
-           case 'x':
-               if (*RExC_parse == '{') {
-                    I32 flags = PERL_SCAN_ALLOW_UNDERSCORES
-                        | PERL_SCAN_DISALLOW_PREFIX;
-                   char * const e = strchr(RExC_parse++, '}');
-                    if (!e)
-                        vFAIL("Missing right brace on \\x{}");
-
-                   numlen = e - RExC_parse;
-                   value = grok_hex(RExC_parse, &numlen, &flags, NULL);
-                   RExC_parse = e + 1;
-               }
-               else {
-                    I32 flags = PERL_SCAN_DISALLOW_PREFIX;
-                   numlen = 2;
-                   value = grok_hex(RExC_parse, &numlen, &flags, NULL);
-                   RExC_parse += numlen;
-               }
-               if (PL_encoding && value < 0x100)
-                   goto recode_encoding;
-               break;
-           case 'c':
-               value = grok_bslash_c(*RExC_parse++, SIZE_ONLY);
-               break;
-           case '0': case '1': case '2': case '3': case '4':
-           case '5': case '6': case '7':
-               {
-                   /* Take 1-3 octal digits */
-                   I32 flags = PERL_SCAN_SILENT_ILLDIGIT;
-                   numlen = 3;
-                   value = grok_oct(--RExC_parse, &numlen, &flags, NULL);
-                   RExC_parse += numlen;
-                   if (PL_encoding && value < 0x100)
-                       goto recode_encoding;
-                   break;
-               }
-           recode_encoding:
-               {
-                   SV* enc = PL_encoding;
-                   value = reg_recode((const char)(U8)value, &enc);
-                   if (!enc && SIZE_ONLY)
-                       ckWARNreg(RExC_parse,
-                                 "Invalid escape in the specified encoding");
-                   break;
-               }
-           default:
-               /* Allow \_ to not give an error */
-               if (!SIZE_ONLY && isALNUM(value) && value != '_') {
-                   ckWARN2reg(RExC_parse,
-                              "Unrecognized escape \\%c in character class passed through",
-                              (int)value);
-               }
-               break;
-           }
-       } /* end of \blah */
-#ifdef EBCDIC
-       else
-           literal_endpoint++;
-#endif
-
-       if (namedclass > OOB_NAMEDCLASS) { /* this is a named class \blah */
-
-           /* What matches in a locale is not known until runtime, so need to
-            * (one time per class) allocate extra space to pass to regexec.
-            * The space will contain a bit for each named class that is to be
-            * matched against.  This isn't needed for \p{} and pseudo-classes,
-            * as they are not affected by locale, and hence are dealt with
-            * separately */
-           if (LOC && namedclass < ANYOF_MAX && ! need_class) {
-               need_class = 1;
-               if (SIZE_ONLY) {
-#ifdef ANYOF_CLASS_ADD_SKIP
-                   RExC_size += ANYOF_CLASS_ADD_SKIP;
-#endif
-               }
-               else {
-#ifdef ANYOF_CLASS_ADD_SKIP
-                   RExC_emit += ANYOF_CLASS_ADD_SKIP;
-#endif
-                   ANYOF_CLASS_ZERO(ret);
-               }
-               ANYOF_FLAGS(ret) |= ANYOF_CLASS;
-           }
-
-           /* a bad range like a-\d, a-[:digit:].  The '-' is taken as a
-            * literal */
-           if (range) {
-               if (!SIZE_ONLY) {
-                   const int w =
-                       RExC_parse >= rangebegin ?
-                       RExC_parse - rangebegin : 0;
-                   ckWARN4reg(RExC_parse,
-                              "False [] range \"%*.*s\"",
-                              w, w, rangebegin);
-
-                   if (prevvalue < 256) {
-                       stored +=
-                         S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) prevvalue);
-                       stored +=
-                         S_set_regclass_bit(aTHX_ pRExC_state, ret, '-');
-                   }
-                   else {
-                       ANYOF_FLAGS(ret) |= ANYOF_UTF8;
-                       Perl_sv_catpvf(aTHX_ listsv,
-                          "%04"UVxf"\n%04"UVxf"\n", (UV)prevvalue, (UV) '-');
-                   }
-               }
-
-               range = 0; /* this was not a true range */
-           }
-
-
-    
-           if (!SIZE_ONLY) {
-               const char *what = NULL;
-               char yesno = 0;
-
-               /* Possible truncation here but in some 64-bit environments
-                * the compiler gets heartburn about switch on 64-bit values.
-                * A similar issue a little earlier when switching on value.
-                * --jhi */
-               switch ((I32)namedclass) {
-               
-               case _C_C_T_(ALNUMC, isALNUMC_L1(value), isALNUMC(value), "XPosixAlnum");
-               case _C_C_T_(ALPHA, isALPHA_L1(value), isALPHA(value), "XPosixAlpha");
-               case _C_C_T_(BLANK, isBLANK_L1(value), isBLANK(value), "XPosixBlank");
-               case _C_C_T_(CNTRL, isCNTRL_L1(value), isCNTRL(value), "XPosixCntrl");
-               case _C_C_T_(GRAPH, isGRAPH_L1(value), isGRAPH(value), "XPosixGraph");
-               case _C_C_T_(LOWER, isLOWER_L1(value), isLOWER(value), "XPosixLower");
-               case _C_C_T_(PRINT, isPRINT_L1(value), isPRINT(value), "XPosixPrint");
-               case _C_C_T_(PSXSPC, isPSXSPC_L1(value), isPSXSPC(value), "XPosixSpace");
-               case _C_C_T_(PUNCT, isPUNCT_L1(value), isPUNCT(value), "XPosixPunct");
-               case _C_C_T_(UPPER, isUPPER_L1(value), isUPPER(value), "XPosixUpper");
-#ifdef BROKEN_UNICODE_CHARCLASS_MAPPINGS
-                /* \s, \w match all unicode if utf8. */
-                case _C_C_T_(SPACE, isSPACE_L1(value), isSPACE(value), "SpacePerl");
-                case _C_C_T_(ALNUM, isWORDCHAR_L1(value), isALNUM(value), "Word");
-#else
-                /* \s, \w match ascii and locale only */
-                case _C_C_T_(SPACE, isSPACE_L1(value), isSPACE(value), "PerlSpace");
-                case _C_C_T_(ALNUM, isWORDCHAR_L1(value), isALNUM(value), "PerlWord");
-#endif         
-               case _C_C_T_(XDIGIT, isXDIGIT_L1(value), isXDIGIT(value), "XPosixXDigit");
-               case _C_C_T_NOLOC_(VERTWS, is_VERTWS_latin1(&value), "VertSpace");
-               case _C_C_T_NOLOC_(HORIZWS, is_HORIZWS_latin1(&value), "HorizSpace");
-               case ANYOF_ASCII:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_ASCII);
-                   else {
-                       for (value = 0; value < 128; value++)
-                           stored +=
-                              S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) ASCII_TO_NATIVE(value));
-                   }
-                   yesno = '+';
-                   what = NULL;        /* Doesn't match outside ascii, so
-                                          don't want to add +utf8:: */
-                   break;
-               case ANYOF_NASCII:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NASCII);
-                   else {
-                       for (value = 128; value < 256; value++)
-                           stored +=
-                              S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) ASCII_TO_NATIVE(value));
-                   }
-                   ANYOF_FLAGS(ret) |= ANYOF_UNICODE_ALL;
-                   yesno = '!';
-                   what = "ASCII";
-                   break;              
-               case ANYOF_DIGIT:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_DIGIT);
-                   else {
-                       /* consecutive digits assumed */
-                       for (value = '0'; value <= '9'; value++)
-                           stored +=
-                              S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) value);
-                   }
-                   yesno = '+';
-                   what = POSIX_CC_UNI_NAME("Digit");
-                   break;
-               case ANYOF_NDIGIT:
-                   if (LOC)
-                       ANYOF_CLASS_SET(ret, ANYOF_NDIGIT);
-                   else {
-                       /* consecutive digits assumed */
-                       for (value = 0; value < '0'; value++)
-                           stored +=
-                              S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) value);
-                       for (value = '9' + 1; value < 256; value++)
-                           stored +=
-                              S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) value);
-                   }
-                   yesno = '!';
-                   what = POSIX_CC_UNI_NAME("Digit");
-                   if (ASCII_RESTRICTED ) {
-                       ANYOF_FLAGS(ret) |= ANYOF_UNICODE_ALL;
-                   }
-                   break;              
-               case ANYOF_MAX:
-                   /* this is to handle \p and \P */
-                   break;
-               default:
-                   vFAIL("Invalid [::] class");
-                   break;
-               }
-               if (what && ! (ASCII_RESTRICTED)) {
-                   /* Strings such as "+utf8::isWord\n" */
-                   Perl_sv_catpvf(aTHX_ listsv, "%cutf8::Is%s\n", yesno, what);
-                   ANYOF_FLAGS(ret) |= ANYOF_UTF8;
-               }
-
-               continue;
-           }
-       } /* end of namedclass \blah */
-
-       if (range) {
-           if (prevvalue > (IV)value) /* b-a */ {
-               const int w = RExC_parse - rangebegin;
-               Simple_vFAIL4("Invalid [] range \"%*.*s\"", w, w, rangebegin);
-               range = 0; /* not a valid range */
-           }
-       }
-       else {
-           prevvalue = value; /* save the beginning of the range */
-           if (*RExC_parse == '-' && RExC_parse+1 < RExC_end &&
-               RExC_parse[1] != ']') {
-               RExC_parse++;
-
-               /* a bad range like \w-, [:word:]- ? */
-               if (namedclass > OOB_NAMEDCLASS) {
-                   if (ckWARN(WARN_REGEXP)) {
-                       const int w =
-                           RExC_parse >= rangebegin ?
-                           RExC_parse - rangebegin : 0;
-                       vWARN4(RExC_parse,
-                              "False [] range \"%*.*s\"",
-                              w, w, rangebegin);
-                   }
-                   if (!SIZE_ONLY)
-                       stored +=
-                            S_set_regclass_bit(aTHX_ pRExC_state, ret, '-');
-               } else
-                   range = 1;  /* yeah, it's a range! */
-               continue;       /* but do it the next time */
-           }
-       }
-
-       /* now is the next time */
-       if (!SIZE_ONLY) {
-           if (prevvalue < 256) {
-               const IV ceilvalue = value < 256 ? value : 255;
-               IV i;
-#ifdef EBCDIC
-               /* In EBCDIC [\x89-\x91] should include
-                * the \x8e but [i-j] should not. */
-               if (literal_endpoint == 2 &&
-                   ((isLOWER(prevvalue) && isLOWER(ceilvalue)) ||
-                    (isUPPER(prevvalue) && isUPPER(ceilvalue))))
-               {
-                   if (isLOWER(prevvalue)) {
-                       for (i = prevvalue; i <= ceilvalue; i++)
-                           if (isLOWER(i) && !ANYOF_BITMAP_TEST(ret,i)) {
-                               stored +=
-                                  S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) i);
-                           }
-                   } else {
-                       for (i = prevvalue; i <= ceilvalue; i++)
-                           if (isUPPER(i) && !ANYOF_BITMAP_TEST(ret,i)) {
-                               stored +=
-                                  S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) i);
-                           }
-                   }
-               }
-               else
-#endif
-                     for (i = prevvalue; i <= ceilvalue; i++) {
-                       stored += S_set_regclass_bit(aTHX_ pRExC_state, ret, (U8) i);
-                     }
-         }
-         if (value > 255 || UTF) {
-               const UV prevnatvalue  = NATIVE_TO_UNI(prevvalue);
-               const UV natvalue      = NATIVE_TO_UNI(value);
-
-               /* If the code point requires utf8 to represent, and we are not
-                * folding, it can't match unless the target is in utf8.  Only
-                * a few code points above 255 fold to below it, so XXX an
-                * optimization would be to know which ones and set the flag
-                * appropriately. */
-               ANYOF_FLAGS(ret) |= (FOLD || value < 256)
-                                   ? ANYOF_NONBITMAP
-                                   : ANYOF_UTF8;
-               if (prevnatvalue < natvalue) { /* '>' case is fatal error above */
-
-                   /* The \t sets the whole range */
-                   Perl_sv_catpvf(aTHX_ listsv, "%04"UVxf"\t%04"UVxf"\n",
-                                  prevnatvalue, natvalue);
-
-                   /* Currently, we don't look at every value in the range.
-                    * Therefore we have to assume the worst case: that if
-                    * folding, it will match more than one character.  But in
-                    * lookbehind patterns, can only be single character
-                    * length, so disallow those folds */
-                   if (FOLD && ! RExC_in_lookbehind) {
-                     OP(ret) = ANYOFV;
-                   }
-               }
-               else if (prevnatvalue == natvalue) {
-                   Perl_sv_catpvf(aTHX_ listsv, "%04"UVxf"\n", natvalue);
-                   if (FOLD) {
-                        U8 foldbuf[UTF8_MAXBYTES_CASE+1];
-                        STRLEN foldlen;
-                        const UV f = to_uni_fold(natvalue, foldbuf, &foldlen);
-
-#ifdef EBCDIC /* RD t/uni/fold ff and 6b */
-                        if (RExC_precomp[0] == ':' &&
-                            RExC_precomp[1] == '[' &&
-                            (f == 0xDF || f == 0x92)) {
-                            f = NATIVE_TO_UNI(f);
-                        }
-#endif
-                        /* If folding and foldable and a single
-                         * character, insert also the folded version
-                         * to the charclass. */
-                        if (f != value) {
-#ifdef EBCDIC /* RD tunifold ligatures s,t fb05, fb06 */
-                            if ((RExC_precomp[0] == ':' &&
-                                 RExC_precomp[1] == '[' &&
-                                 (f == 0xA2 &&
-                                  (value == 0xFB05 || value == 0xFB06))) ?
-                                foldlen == ((STRLEN)UNISKIP(f) - 1) :
-                                foldlen == (STRLEN)UNISKIP(f) )
-#else
-                             if (foldlen == (STRLEN)UNISKIP(f))
-#endif
-                                 Perl_sv_catpvf(aTHX_ listsv,
-                                                "%04"UVxf"\n", f);
-                             else if (! RExC_in_lookbehind) {
-                                 /* Any multicharacter foldings
-                                  * (disallowed in lookbehind patterns)
-                                  * require the following transform:
-                                  * [ABCDEF] -> (?:[ABCabcDEFd]|pq|rst)
-                                  * where E folds into "pq" and F folds
-                                  * into "rst", all other characters
-                                  * fold to single characters.  We save
-                                  * away these multicharacter foldings,
-                                  * to be later saved as part of the
-                                  * additional "s" data. */
-                                 SV *sv;
-
-                                 if (!unicode_alternate)
-                                     unicode_alternate = newAV();
-                                 sv = newSVpvn_utf8((char*)foldbuf, foldlen,
-                                                    TRUE);
-                                 av_push(unicode_alternate, sv);
-                                 OP(ret) = ANYOFV;
-                             }
-                        }
-
-                        /* If folding and the value is one of the Greek
-                         * sigmas insert a few more sigmas to make the
-                         * folding rules of the sigmas to work right.
-                         * Note that not all the possible combinations
-                         * are handled here: some of them are handled
-                         * by the standard folding rules, and some of
-                         * them (literal or EXACTF cases) are handled
-                         * during runtime in regexec.c:S_find_byclass(). */
-                        if (value == UNICODE_GREEK_SMALL_LETTER_FINAL_SIGMA) {
-                             Perl_sv_catpvf(aTHX_ listsv, "%04"UVxf"\n",
-                                            (UV)UNICODE_GREEK_CAPITAL_LETTER_SIGMA);
-                             Perl_sv_catpvf(aTHX_ listsv, "%04"UVxf"\n",
-                                            (UV)UNICODE_GREEK_SMALL_LETTER_SIGMA);
-                        }
-                        else if (value == UNICODE_GREEK_CAPITAL_LETTER_SIGMA)
-                             Perl_sv_catpvf(aTHX_ listsv, "%04"UVxf"\n",
-                                            (UV)UNICODE_GREEK_SMALL_LETTER_SIGMA);
-                   }
-               }
-           }
-#ifdef EBCDIC
-           literal_endpoint = 0;
-#endif
-        }
-
-       range = 0; /* this range (if it was one) is done now */
-    }
-
-
-
-    if (SIZE_ONLY)
-        return ret;
-    /****** !SIZE_ONLY AFTER HERE *********/
-
-    /* Optimize inverted simple patterns (e.g. [^a-z]).  Note that we haven't
-     * set the FOLD flag yet, so this this does optimize those.  It doesn't
-     * optimize locale.  Doing so perhaps could be done as long as there is
-     * nothing like \w in it; some thought also would have to be given to the
-     * interaction with above 0x100 chars */
-    if (! LOC && (ANYOF_FLAGS(ret) & ANYOF_FLAGS_ALL) == ANYOF_INVERT) {
-       for (value = 0; value < ANYOF_BITMAP_SIZE; ++value)
-           ANYOF_BITMAP(ret)[value] ^= 0xFF;
-       stored = 256 - stored;
-
-       /* The inversion means that everything above 255 is matched; and at the
-        * same time we clear the invert flag */
-       ANYOF_FLAGS(ret) = ANYOF_UTF8|ANYOF_UNICODE_ALL;
-    }
-
-    if (FOLD) {
-       SV *sv;
-
-       /* This is the one character in the bitmap that needs special handling
-        * under non-locale folding, as it folds to two characters 'ss'.  This
-        * happens if it is set and not inverting, or isn't set and are
-        * inverting (disallowed in lookbehind patterns because they can't be
-        * variable length) */
-       if (! LOC
-           && ! RExC_in_lookbehind
-           && (cBOOL(ANYOF_BITMAP_TEST(ret, LATIN_SMALL_LETTER_SHARP_S))
-               ^ cBOOL(ANYOF_FLAGS(ret) & ANYOF_INVERT)))
-       {
-           OP(ret) = ANYOFV;   /* Can match more than a single char */
-
-           /* Under Unicode semantics), it can do this when the target string
-            * isn't in utf8 */
-           if (UNI_SEMANTICS) {
-               ANYOF_FLAGS(ret) |= ANYOF_NONBITMAP_NON_UTF8;
-           }
-
-           if (!unicode_alternate) {
-               unicode_alternate = newAV();
-           }
-           sv = newSVpvn_utf8("ss", 2, TRUE);
-           av_push(unicode_alternate, sv);
-       }
-
-       /* Folding in the bitmap is taken care of above, but not for locale
-        * (for which we have to wait to see what folding is in effect at
-        * runtime), and for things not in the bitmap.  Set run-time fold flag
-        * for these */
-       if ((LOC || (ANYOF_FLAGS(ret) & ANYOF_NONBITMAP))) {
-           ANYOF_FLAGS(ret) |= ANYOF_LOC_NONBITMAP_FOLD;
-       }
-    }
-
-    /* A single character class can be "optimized" into an EXACTish node.
-     * Note that since we don't currently count how many characters there are
-     * outside the bitmap, we are XXX missing optimization possibilities for
-     * them.  This optimization can't happen unless this is a truly single
-     * character class, which means that it can't be an inversion into a
-     * many-character class, and there must be no possibility of there being
-     * things outside the bitmap.  'stored' (only) for locales doesn't include
-     * \w, etc, so have to make a special test that they aren't present
-     *
-     * Similarly A 2-character class of the very special form like [bB] can be
-     * optimized into an EXACTFish node, but only for non-locales, and for
-     * characters which only have the two folds; so things like 'fF' and 'Ii'
-     * wouldn't work because they are part of the fold of 'LATIN SMALL LIGATURE
-     * FI'. */
-    if (! (ANYOF_FLAGS(ret) & (ANYOF_NONBITMAP|ANYOF_INVERT|ANYOF_UNICODE_ALL))
-        && (((stored == 1 && ((! (ANYOF_FLAGS(ret) & ANYOF_LOCALE))
-                              || (! ANYOF_CLASS_TEST_ANY_SET(ret)))))
-           || (stored == 2 && ((! (ANYOF_FLAGS(ret) & ANYOF_LOCALE))
-                                && (! _HAS_NONLATIN1_FOLD_CLOSURE_ONLY_FOR_USE_BY_REGCOMP_DOT_C_AND_REGEXEC_DOT_C(value))
-                                /* If the latest code point has a fold whose
-                                 * bit is set, it must be the only other one */
-                               && ((prevvalue = PL_fold_latin1[value]) != (IV)value)
-                                && ANYOF_BITMAP_TEST(ret, prevvalue)))))
-    {
-        /* Note that the information needed to decide to do this optimization
-         * is not currently available until the 2nd pass, and that the actually
-        * used EXACTish node takes less space than the calculated ANYOF node,
-        * and hence the amount of space calculated in the first pass is larger
-         * than actually used, so this optimization doesn't gain us any space.
-        * But an EXACT node is faster than an ANYOF node, and can be combined
-        * with any adjacent EXACT nodes later by the optimizer for further
-        * gains.  The speed of executing an EXACTF is similar to an ANYOF
-        * node, so the optimization advantage comes from the ability to join
-        * it to adjacent EXACT nodes */
-
-        const char * cur_parse= RExC_parse;
-       U8 op;
-        RExC_emit = (regnode *)orig_emit;
-        RExC_parse = (char *)orig_parse;
-
-       if (stored == 1) {
-
-           /* A locale node with one point can be folded; all the other cases
-            * with folding will have two points, since we calculate them above
-            */
-           if (ANYOF_FLAGS(ret) & ANYOF_LOC_NONBITMAP_FOLD) {
-                op = EXACTFL;
-           }
-           else {
-               op = EXACT;
-           }
-       }   /* else 2 chars in the bit map: the folds of each other */
-       else if (AT_LEAST_UNI_SEMANTICS || !isASCII(value)) {
-
-           /* To join adjacent nodes, they must be the exact EXACTish type.
-            * Try to use the most likely type, by using EXACTFU if the regex
-            * calls for them, or is required because the character is
-            * non-ASCII */
-           op = EXACTFU;
-       }
-       else {    /* Otherwise, more likely to be EXACTF type */
-           op = EXACTF;
-       }
-
-       ret = reg_node(pRExC_state, op);
-        RExC_parse = (char *)cur_parse;
-       if (UTF && ! NATIVE_IS_INVARIANT(value)) {
-           *STRING(ret)= UTF8_EIGHT_BIT_HI((U8) value);
-           *(STRING(ret) + 1)= UTF8_EIGHT_BIT_LO((U8) value);
-           STR_LEN(ret)= 2;
-           RExC_emit += STR_SZ(2);
-       }
-       else {
-           *STRING(ret)= (char)value;
-           STR_LEN(ret)= 1;
-           RExC_emit += STR_SZ(1);
-       }
-       SvREFCNT_dec(listsv);
-        return ret;
-    }
-
-    {
-       AV * const av = newAV();
-       SV *rv;
-       /* The 0th element stores the character class description
-        * in its textual form: used later (regexec.c:Perl_regclass_swash())
-        * to initialize the appropriate swash (which gets stored in
-        * the 1st element), and also useful for dumping the regnode.
-        * The 2nd element stores the multicharacter foldings,
-        * used later (regexec.c:S_reginclass()). */
-       av_store(av, 0, listsv);
-       av_store(av, 1, NULL);
-       av_store(av, 2, MUTABLE_SV(unicode_alternate));
-       rv = newRV_noinc(MUTABLE_SV(av));
-       n = add_data(pRExC_state, 1, "s");
-       RExC_rxi->data->data[n] = (void*)rv;
-       ARG_SET(ret, n);
-    }
-    return ret;
-}
-#undef _C_C_T_
-
-
-/* reg_skipcomment()
-
-   Absorbs an /x style # comments from the input stream.
-   Returns true if there is more text remaining in the stream.
-   Will set the REG_SEEN_RUN_ON_COMMENT flag if the comment
-   terminates the pattern without including a newline.
-
-   Note its the callers responsibility to ensure that we are
-   actually in /x mode
-
-*/
-
-STATIC bool
-S_reg_skipcomment(pTHX_ RExC_state_t *pRExC_state)
-{
-    bool ended = 0;
-
-    PERL_ARGS_ASSERT_REG_SKIPCOMMENT;
-
-    while (RExC_parse < RExC_end)
-        if (*RExC_parse++ == '\n') {
-            ended = 1;
-            break;
-        }
-    if (!ended) {
-        /* we ran off the end of the pattern without ending
-           the comment, so we have to add an \n when wrapping */
-        RExC_seen |= REG_SEEN_RUN_ON_COMMENT;
-        return 0;
-    } else
-        return 1;
-}
-
-/* nextchar()
-
-   Advances the parse position, and optionally absorbs
-   "whitespace" from the inputstream.
-
-   Without /x "whitespace" means (?#...) style comments only,
-   with /x this means (?#...) and # comments and whitespace proper.
-
-   Returns the RExC_parse point from BEFORE the scan occurs.
-
-   This is the /x friendly way of saying RExC_parse++.
-*/
-
-STATIC char*
-S_nextchar(pTHX_ RExC_state_t *pRExC_state)
-{
-    char* const retval = RExC_parse++;
-
-    PERL_ARGS_ASSERT_NEXTCHAR;
-
-    for (;;) {
-       if (*RExC_parse == '(' && RExC_parse[1] == '?' &&
-               RExC_parse[2] == '#') {
-           while (*RExC_parse != ')') {
-               if (RExC_parse == RExC_end)
-                   FAIL("Sequence (?#... not terminated");
-               RExC_parse++;
-           }
-           RExC_parse++;
-           continue;
-       }
-       if (RExC_flags & RXf_PMf_EXTENDED) {
-           if (isSPACE(*RExC_parse)) {
-               RExC_parse++;
-               continue;
-           }
-           else if (*RExC_parse == '#') {
-               if ( reg_skipcomment( pRExC_state ) )
-                   continue;
-           }
-       }
-       return retval;
-    }
-}
-
-/*
-- reg_node - emit a node
-*/
-STATIC regnode *                       /* Location. */
-S_reg_node(pTHX_ RExC_state_t *pRExC_state, U8 op)
-{
-    dVAR;
-    register regnode *ptr;
-    regnode * const ret = RExC_emit;
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_REG_NODE;
-
-    if (SIZE_ONLY) {
-       SIZE_ALIGN(RExC_size);
-       RExC_size += 1;
-       return(ret);
-    }
-    if (RExC_emit >= RExC_emit_bound)
-        Perl_croak(aTHX_ "panic: reg_node overrun trying to emit %d", op);
-
-    NODE_ALIGN_FILL(ret);
-    ptr = ret;
-    FILL_ADVANCE_NODE(ptr, op);
-    REH_CALL_COMP_NODE_HOOK(pRExC_state->rx, (ptr) - 1);
-#ifdef RE_TRACK_PATTERN_OFFSETS
-    if (RExC_offsets) {         /* MJD */
-       MJD_OFFSET_DEBUG(("%s:%d: (op %s) %s %"UVuf" (len %"UVuf") (max %"UVuf").\n", 
-              "reg_node", __LINE__, 
-              PL_reg_name[op],
-              (UV)(RExC_emit - RExC_emit_start) > RExC_offsets[0] 
-               ? "Overwriting end of array!\n" : "OK",
-              (UV)(RExC_emit - RExC_emit_start),
-              (UV)(RExC_parse - RExC_start),
-              (UV)RExC_offsets[0])); 
-       Set_Node_Offset(RExC_emit, RExC_parse + (op == END));
-    }
-#endif
-    RExC_emit = ptr;
-    return(ret);
-}
-
-/*
-- reganode - emit a node with an argument
-*/
-STATIC regnode *                       /* Location. */
-S_reganode(pTHX_ RExC_state_t *pRExC_state, U8 op, U32 arg)
-{
-    dVAR;
-    register regnode *ptr;
-    regnode * const ret = RExC_emit;
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_REGANODE;
-
-    if (SIZE_ONLY) {
-       SIZE_ALIGN(RExC_size);
-       RExC_size += 2;
-       /* 
-          We can't do this:
-          
-          assert(2==regarglen[op]+1); 
-       
-          Anything larger than this has to allocate the extra amount.
-          If we changed this to be:
-          
-          RExC_size += (1 + regarglen[op]);
-          
-          then it wouldn't matter. Its not clear what side effect
-          might come from that so its not done so far.
-          -- dmq
-       */
-       return(ret);
-    }
-    if (RExC_emit >= RExC_emit_bound)
-        Perl_croak(aTHX_ "panic: reg_node overrun trying to emit %d", op);
-
-    NODE_ALIGN_FILL(ret);
-    ptr = ret;
-    FILL_ADVANCE_NODE_ARG(ptr, op, arg);
-    REH_CALL_COMP_NODE_HOOK(pRExC_state->rx, (ptr) - 2);
-#ifdef RE_TRACK_PATTERN_OFFSETS
-    if (RExC_offsets) {         /* MJD */
-       MJD_OFFSET_DEBUG(("%s(%d): (op %s) %s %"UVuf" <- %"UVuf" (max %"UVuf").\n", 
-              "reganode",
-             __LINE__,
-             PL_reg_name[op],
-              (UV)(RExC_emit - RExC_emit_start) > RExC_offsets[0] ? 
-              "Overwriting end of array!\n" : "OK",
-              (UV)(RExC_emit - RExC_emit_start),
-              (UV)(RExC_parse - RExC_start),
-              (UV)RExC_offsets[0])); 
-       Set_Cur_Node_Offset;
-    }
-#endif            
-    RExC_emit = ptr;
-    return(ret);
-}
-
-/*
-- reguni - emit (if appropriate) a Unicode character
-*/
-STATIC STRLEN
-S_reguni(pTHX_ const RExC_state_t *pRExC_state, UV uv, char* s)
-{
-    dVAR;
-
-    PERL_ARGS_ASSERT_REGUNI;
-
-    return SIZE_ONLY ? UNISKIP(uv) : (uvchr_to_utf8((U8*)s, uv) - (U8*)s);
-}
-
-/*
-- reginsert - insert an operator in front of already-emitted operand
-*
-* Means relocating the operand.
-*/
-STATIC void
-S_reginsert(pTHX_ RExC_state_t *pRExC_state, U8 op, regnode *opnd, U32 depth)
-{
-    dVAR;
-    register regnode *src;
-    register regnode *dst;
-    register regnode *place;
-    const int offset = regarglen[(U8)op];
-    const int size = NODE_STEP_REGNODE + offset;
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_REGINSERT;
-    PERL_UNUSED_ARG(depth);
-/* (PL_regkind[(U8)op] == CURLY ? EXTRA_STEP_2ARGS : 0); */
-    DEBUG_PARSE_FMT("inst"," - %s",PL_reg_name[op]);
-    if (SIZE_ONLY) {
-       RExC_size += size;
-       return;
-    }
-
-    src = RExC_emit;
-    RExC_emit += size;
-    dst = RExC_emit;
-    if (RExC_open_parens) {
-        int paren;
-        /*DEBUG_PARSE_FMT("inst"," - %"IVdf, (IV)RExC_npar);*/
-        for ( paren=0 ; paren < RExC_npar ; paren++ ) {
-            if ( RExC_open_parens[paren] >= opnd ) {
-                /*DEBUG_PARSE_FMT("open"," - %d",size);*/
-                RExC_open_parens[paren] += size;
-            } else {
-                /*DEBUG_PARSE_FMT("open"," - %s","ok");*/
-            }
-            if ( RExC_close_parens[paren] >= opnd ) {
-                /*DEBUG_PARSE_FMT("close"," - %d",size);*/
-                RExC_close_parens[paren] += size;
-            } else {
-                /*DEBUG_PARSE_FMT("close"," - %s","ok");*/
-            }
-        }
-    }
-
-    while (src > opnd) {
-       StructCopy(--src, --dst, regnode);
-#ifdef RE_TRACK_PATTERN_OFFSETS
-        if (RExC_offsets) {     /* MJD 20010112 */
-           MJD_OFFSET_DEBUG(("%s(%d): (op %s) %s copy %"UVuf" -> %"UVuf" (max %"UVuf").\n",
-                  "reg_insert",
-                 __LINE__,
-                 PL_reg_name[op],
-                  (UV)(dst - RExC_emit_start) > RExC_offsets[0] 
-                   ? "Overwriting end of array!\n" : "OK",
-                  (UV)(src - RExC_emit_start),
-                  (UV)(dst - RExC_emit_start),
-                  (UV)RExC_offsets[0])); 
-           Set_Node_Offset_To_R(dst-RExC_emit_start, Node_Offset(src));
-           Set_Node_Length_To_R(dst-RExC_emit_start, Node_Length(src));
-        }
-#endif
-    }
-    
-
-    place = opnd;              /* Op node, where operand used to be. */
-#ifdef RE_TRACK_PATTERN_OFFSETS
-    if (RExC_offsets) {         /* MJD */
-       MJD_OFFSET_DEBUG(("%s(%d): (op %s) %s %"UVuf" <- %"UVuf" (max %"UVuf").\n", 
-              "reginsert",
-             __LINE__,
-             PL_reg_name[op],
-              (UV)(place - RExC_emit_start) > RExC_offsets[0] 
-              ? "Overwriting end of array!\n" : "OK",
-              (UV)(place - RExC_emit_start),
-              (UV)(RExC_parse - RExC_start),
-              (UV)RExC_offsets[0]));
-       Set_Node_Offset(place, RExC_parse);
-       Set_Node_Length(place, 1);
-    }
-#endif    
-    src = NEXTOPER(place);
-    FILL_ADVANCE_NODE(place, op);
-    REH_CALL_COMP_NODE_HOOK(pRExC_state->rx, (place) - 1);
-    Zero(src, offset, regnode);
-}
-
-/*
-- regtail - set the next-pointer at the end of a node chain of p to val.
-- SEE ALSO: regtail_study
-*/
-/* TODO: All three parms should be const */
-STATIC void
-S_regtail(pTHX_ RExC_state_t *pRExC_state, regnode *p, const regnode *val,U32 depth)
-{
-    dVAR;
-    register regnode *scan;
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_REGTAIL;
-#ifndef DEBUGGING
-    PERL_UNUSED_ARG(depth);
-#endif
-
-    if (SIZE_ONLY)
-       return;
-
-    /* Find last node. */
-    scan = p;
-    for (;;) {
-       regnode * const temp = regnext(scan);
-        DEBUG_PARSE_r({
-            SV * const mysv=sv_newmortal();
-            DEBUG_PARSE_MSG((scan==p ? "tail" : ""));
-            regprop(RExC_rx, mysv, scan);
-            PerlIO_printf(Perl_debug_log, "~ %s (%d) %s %s\n",
-                SvPV_nolen_const(mysv), REG_NODE_NUM(scan),
-                    (temp == NULL ? "->" : ""),
-                    (temp == NULL ? PL_reg_name[OP(val)] : "")
-            );
-        });
-        if (temp == NULL)
-            break;
-        scan = temp;
-    }
-
-    if (reg_off_by_arg[OP(scan)]) {
-        ARG_SET(scan, val - scan);
-    }
-    else {
-        NEXT_OFF(scan) = val - scan;
-    }
-}
-
-#ifdef DEBUGGING
-/*
-- regtail_study - set the next-pointer at the end of a node chain of p to val.
-- Look for optimizable sequences at the same time.
-- currently only looks for EXACT chains.
-
-This is experimental code. The idea is to use this routine to perform 
-in place optimizations on branches and groups as they are constructed,
-with the long term intention of removing optimization from study_chunk so
-that it is purely analytical.
-
-Currently only used when in DEBUG mode. The macro REGTAIL_STUDY() is used
-to control which is which.
-
-*/
-/* TODO: All four parms should be const */
-
-STATIC U8
-S_regtail_study(pTHX_ RExC_state_t *pRExC_state, regnode *p, const regnode *val,U32 depth)
-{
-    dVAR;
-    register regnode *scan;
-    U8 exact = PSEUDO;
-#ifdef EXPERIMENTAL_INPLACESCAN
-    I32 min = 0;
-#endif
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_REGTAIL_STUDY;
-
-
-    if (SIZE_ONLY)
-        return exact;
-
-    /* Find last node. */
-
-    scan = p;
-    for (;;) {
-        regnode * const temp = regnext(scan);
-#ifdef EXPERIMENTAL_INPLACESCAN
-        if (PL_regkind[OP(scan)] == EXACT)
-            if (join_exact(pRExC_state,scan,&min,1,val,depth+1))
-                return EXACT;
-#endif
-        if ( exact ) {
-            switch (OP(scan)) {
-                case EXACT:
-                case EXACTF:
-                case EXACTFU:
-                case EXACTFL:
-                        if( exact == PSEUDO )
-                            exact= OP(scan);
-                        else if ( exact != OP(scan) )
-                            exact= 0;
-                case NOTHING:
-                    break;
-                default:
-                    exact= 0;
-            }
-        }
-        DEBUG_PARSE_r({
-            SV * const mysv=sv_newmortal();
-            DEBUG_PARSE_MSG((scan==p ? "tsdy" : ""));
-            regprop(RExC_rx, mysv, scan);
-            PerlIO_printf(Perl_debug_log, "~ %s (%d) -> %s\n",
-                SvPV_nolen_const(mysv),
-                REG_NODE_NUM(scan),
-                PL_reg_name[exact]);
-        });
-       if (temp == NULL)
-           break;
-       scan = temp;
-    }
-    DEBUG_PARSE_r({
-        SV * const mysv_val=sv_newmortal();
-        DEBUG_PARSE_MSG("");
-        regprop(RExC_rx, mysv_val, val);
-        PerlIO_printf(Perl_debug_log, "~ attach to %s (%"IVdf") offset to %"IVdf"\n",
-                     SvPV_nolen_const(mysv_val),
-                     (IV)REG_NODE_NUM(val),
-                     (IV)(val - scan)
-        );
-    });
-    if (reg_off_by_arg[OP(scan)]) {
-       ARG_SET(scan, val - scan);
-    }
-    else {
-       NEXT_OFF(scan) = val - scan;
-    }
-
-    return exact;
-}
-#endif
-
-/*
- - regdump - dump a regexp onto Perl_debug_log in vaguely comprehensible form
- */
-#ifdef DEBUGGING
-static void 
-S_regdump_extflags(pTHX_ const char *lead, const U32 flags)
-{
-    int bit;
-    int set=0;
-    regex_charset cs;
-
-    for (bit=0; bit<32; bit++) {
-        if (flags & (1<<bit)) {
-           if ((1<<bit) & RXf_PMf_CHARSET) {   /* Output separately, below */
-               continue;
-           }
-            if (!set++ && lead) 
-                PerlIO_printf(Perl_debug_log, "%s",lead);
-            PerlIO_printf(Perl_debug_log, "%s ",PL_reg_extflags_name[bit]);
-        }              
-    }     
-    if ((cs = get_regex_charset(flags)) != REGEX_DEPENDS_CHARSET) {
-            if (!set++ && lead) {
-                PerlIO_printf(Perl_debug_log, "%s",lead);
-            }
-            switch (cs) {
-                case REGEX_UNICODE_CHARSET:
-                    PerlIO_printf(Perl_debug_log, "UNICODE");
-                    break;
-                case REGEX_LOCALE_CHARSET:
-                    PerlIO_printf(Perl_debug_log, "LOCALE");
-                    break;
-                case REGEX_ASCII_RESTRICTED_CHARSET:
-                    PerlIO_printf(Perl_debug_log, "ASCII-RESTRICTED");
-                    break;
-                default:
-                    PerlIO_printf(Perl_debug_log, "UNKNOWN CHARACTER SET");
-                    break;
-            }
-    }
-    if (lead)  {
-        if (set) 
-            PerlIO_printf(Perl_debug_log, "\n");
-        else 
-            PerlIO_printf(Perl_debug_log, "%s[none-set]\n",lead);
-    }            
-}   
-#endif
-
-void
-Perl_regdump(pTHX_ const regexp *r)
-{
-#ifdef DEBUGGING
-    dVAR;
-    SV * const sv = sv_newmortal();
-    SV *dsv= sv_newmortal();
-    RXi_GET_DECL(r,ri);
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_REGDUMP;
-
-    (void)dumpuntil(r, ri->program, ri->program + 1, NULL, NULL, sv, 0, 0);
-
-    /* Header fields of interest. */
-    if (r->anchored_substr) {
-       RE_PV_QUOTED_DECL(s, 0, dsv, SvPVX_const(r->anchored_substr), 
-           RE_SV_DUMPLEN(r->anchored_substr), 30);
-       PerlIO_printf(Perl_debug_log,
-                     "anchored %s%s at %"IVdf" ",
-                     s, RE_SV_TAIL(r->anchored_substr),
-                     (IV)r->anchored_offset);
-    } else if (r->anchored_utf8) {
-       RE_PV_QUOTED_DECL(s, 1, dsv, SvPVX_const(r->anchored_utf8), 
-           RE_SV_DUMPLEN(r->anchored_utf8), 30);
-       PerlIO_printf(Perl_debug_log,
-                     "anchored utf8 %s%s at %"IVdf" ",
-                     s, RE_SV_TAIL(r->anchored_utf8),
-                     (IV)r->anchored_offset);
-    }                
-    if (r->float_substr) {
-       RE_PV_QUOTED_DECL(s, 0, dsv, SvPVX_const(r->float_substr), 
-           RE_SV_DUMPLEN(r->float_substr), 30);
-       PerlIO_printf(Perl_debug_log,
-                     "floating %s%s at %"IVdf"..%"UVuf" ",
-                     s, RE_SV_TAIL(r->float_substr),
-                     (IV)r->float_min_offset, (UV)r->float_max_offset);
-    } else if (r->float_utf8) {
-       RE_PV_QUOTED_DECL(s, 1, dsv, SvPVX_const(r->float_utf8), 
-           RE_SV_DUMPLEN(r->float_utf8), 30);
-       PerlIO_printf(Perl_debug_log,
-                     "floating utf8 %s%s at %"IVdf"..%"UVuf" ",
-                     s, RE_SV_TAIL(r->float_utf8),
-                     (IV)r->float_min_offset, (UV)r->float_max_offset);
-    }
-    if (r->check_substr || r->check_utf8)
-       PerlIO_printf(Perl_debug_log,
-                     (const char *)
-                     (r->check_substr == r->float_substr
-                      && r->check_utf8 == r->float_utf8
-                      ? "(checking floating" : "(checking anchored"));
-    if (r->extflags & RXf_NOSCAN)
-       PerlIO_printf(Perl_debug_log, " noscan");
-    if (r->extflags & RXf_CHECK_ALL)
-       PerlIO_printf(Perl_debug_log, " isall");
-    if (r->check_substr || r->check_utf8)
-       PerlIO_printf(Perl_debug_log, ") ");
-
-    if (ri->regstclass) {
-       regprop(r, sv, ri->regstclass);
-       PerlIO_printf(Perl_debug_log, "stclass %s ", SvPVX_const(sv));
-    }
-    if (r->extflags & RXf_ANCH) {
-       PerlIO_printf(Perl_debug_log, "anchored");
-       if (r->extflags & RXf_ANCH_BOL)
-           PerlIO_printf(Perl_debug_log, "(BOL)");
-       if (r->extflags & RXf_ANCH_MBOL)
-           PerlIO_printf(Perl_debug_log, "(MBOL)");
-       if (r->extflags & RXf_ANCH_SBOL)
-           PerlIO_printf(Perl_debug_log, "(SBOL)");
-       if (r->extflags & RXf_ANCH_GPOS)
-           PerlIO_printf(Perl_debug_log, "(GPOS)");
-       PerlIO_putc(Perl_debug_log, ' ');
-    }
-    if (r->extflags & RXf_GPOS_SEEN)
-       PerlIO_printf(Perl_debug_log, "GPOS:%"UVuf" ", (UV)r->gofs);
-    if (r->intflags & PREGf_SKIP)
-       PerlIO_printf(Perl_debug_log, "plus ");
-    if (r->intflags & PREGf_IMPLICIT)
-       PerlIO_printf(Perl_debug_log, "implicit ");
-    PerlIO_printf(Perl_debug_log, "minlen %"IVdf" ", (IV)r->minlen);
-    if (r->extflags & RXf_EVAL_SEEN)
-       PerlIO_printf(Perl_debug_log, "with eval ");
-    PerlIO_printf(Perl_debug_log, "\n");
-    DEBUG_FLAGS_r(regdump_extflags("r->extflags: ",r->extflags));            
-#else
-    PERL_ARGS_ASSERT_REGDUMP;
-    PERL_UNUSED_CONTEXT;
-    PERL_UNUSED_ARG(r);
-#endif /* DEBUGGING */
-}
-
-/*
-- regprop - printable representation of opcode
-*/
-#define EMIT_ANYOF_TEST_SEPARATOR(do_sep,sv,flags) \
-STMT_START { \
-        if (do_sep) {                           \
-            Perl_sv_catpvf(aTHX_ sv,"%s][%s",PL_colors[1],PL_colors[0]); \
-            if (flags & ANYOF_INVERT)           \
-                /*make sure the invert info is in each */ \
-                sv_catpvs(sv, "^");             \
-            do_sep = 0;                         \
-        }                                       \
-} STMT_END
-
-void
-Perl_regprop(pTHX_ const regexp *prog, SV *sv, const regnode *o)
-{
-#ifdef DEBUGGING
-    dVAR;
-    register int k;
-    RXi_GET_DECL(prog,progi);
-    GET_RE_DEBUG_FLAGS_DECL;
-    
-    PERL_ARGS_ASSERT_REGPROP;
-
-    sv_setpvs(sv, "");
-
-    if (OP(o) > REGNODE_MAX)           /* regnode.type is unsigned */
-       /* It would be nice to FAIL() here, but this may be called from
-          regexec.c, and it would be hard to supply pRExC_state. */
-       Perl_croak(aTHX_ "Corrupted regexp opcode %d > %d", (int)OP(o), (int)REGNODE_MAX);
-    sv_catpv(sv, PL_reg_name[OP(o)]); /* Take off const! */
-
-    k = PL_regkind[OP(o)];
-
-    if (k == EXACT) {
-       sv_catpvs(sv, " ");
-       /* Using is_utf8_string() (via PERL_PV_UNI_DETECT) 
-        * is a crude hack but it may be the best for now since 
-        * we have no flag "this EXACTish node was UTF-8" 
-        * --jhi */
-       pv_pretty(sv, STRING(o), STR_LEN(o), 60, PL_colors[0], PL_colors[1],
-                 PERL_PV_ESCAPE_UNI_DETECT |
-                 PERL_PV_ESCAPE_NONASCII   |
-                 PERL_PV_PRETTY_ELLIPSES   |
-                 PERL_PV_PRETTY_LTGT       |
-                 PERL_PV_PRETTY_NOCLEAR
-                 );
-    } else if (k == TRIE) {
-       /* print the details of the trie in dumpuntil instead, as
-        * progi->data isn't available here */
-        const char op = OP(o);
-        const U32 n = ARG(o);
-        const reg_ac_data * const ac = IS_TRIE_AC(op) ?
-               (reg_ac_data *)progi->data->data[n] :
-               NULL;
-        const reg_trie_data * const trie
-           = (reg_trie_data*)progi->data->data[!IS_TRIE_AC(op) ? n : ac->trie];
-        
-        Perl_sv_catpvf(aTHX_ sv, "-%s",PL_reg_name[o->flags]);
-        DEBUG_TRIE_COMPILE_r(
-            Perl_sv_catpvf(aTHX_ sv,
-                "<S:%"UVuf"/%"IVdf" W:%"UVuf" L:%"UVuf"/%"UVuf" C:%"UVuf"/%"UVuf">",
-                (UV)trie->startstate,
-                (IV)trie->statecount-1, /* -1 because of the unused 0 element */
-                (UV)trie->wordcount,
-                (UV)trie->minlen,
-                (UV)trie->maxlen,
-                (UV)TRIE_CHARCOUNT(trie),
-                (UV)trie->uniquecharcount
-            )
-        );
-        if ( IS_ANYOF_TRIE(op) || trie->bitmap ) {
-            int i;
-            int rangestart = -1;
-            U8* bitmap = IS_ANYOF_TRIE(op) ? (U8*)ANYOF_BITMAP(o) : (U8*)TRIE_BITMAP(trie);
-            sv_catpvs(sv, "[");
-            for (i = 0; i <= 256; i++) {
-                if (i < 256 && BITMAP_TEST(bitmap,i)) {
-                    if (rangestart == -1)
-                        rangestart = i;
-                } else if (rangestart != -1) {
-                    if (i <= rangestart + 3)
-                        for (; rangestart < i; rangestart++)
-                            put_byte(sv, rangestart);
-                    else {
-                        put_byte(sv, rangestart);
-                        sv_catpvs(sv, "-");
-                        put_byte(sv, i - 1);
-                    }
-                    rangestart = -1;
-                }
-            }
-            sv_catpvs(sv, "]");
-        } 
-        
-    } else if (k == CURLY) {
-       if (OP(o) == CURLYM || OP(o) == CURLYN || OP(o) == CURLYX)
-           Perl_sv_catpvf(aTHX_ sv, "[%d]", o->flags); /* Parenth number */
-       Perl_sv_catpvf(aTHX_ sv, " {%d,%d}", ARG1(o), ARG2(o));
-    }
-    else if (k == WHILEM && o->flags)                  /* Ordinal/of */
-       Perl_sv_catpvf(aTHX_ sv, "[%d/%d]", o->flags & 0xf, o->flags>>4);
-    else if (k == REF || k == OPEN || k == CLOSE || k == GROUPP || OP(o)==ACCEPT) {
-       Perl_sv_catpvf(aTHX_ sv, "%d", (int)ARG(o));    /* Parenth number */
-       if ( RXp_PAREN_NAMES(prog) ) {
-            if ( k != REF || (OP(o) < NREF)) {
-               AV *list= MUTABLE_AV(progi->data->data[progi->name_list_idx]);
-               SV **name= av_fetch(list, ARG(o), 0 );
-               if (name)
-                   Perl_sv_catpvf(aTHX_ sv, " '%"SVf"'", SVfARG(*name));
-            }      
-            else {
-                AV *list= MUTABLE_AV(progi->data->data[ progi->name_list_idx ]);
-                SV *sv_dat= MUTABLE_SV(progi->data->data[ ARG( o ) ]);
-                I32 *nums=(I32*)SvPVX(sv_dat);
-                SV **name= av_fetch(list, nums[0], 0 );
-                I32 n;
-                if (name) {
-                    for ( n=0; n<SvIVX(sv_dat); n++ ) {
-                        Perl_sv_catpvf(aTHX_ sv, "%s%"IVdf,
-                                   (n ? "," : ""), (IV)nums[n]);
-                    }
-                    Perl_sv_catpvf(aTHX_ sv, " '%"SVf"'", SVfARG(*name));
-                }
-            }
-        }            
-    } else if (k == GOSUB) 
-       Perl_sv_catpvf(aTHX_ sv, "%d[%+d]", (int)ARG(o),(int)ARG2L(o)); /* Paren and offset */
-    else if (k == VERB) {
-        if (!o->flags) 
-            Perl_sv_catpvf(aTHX_ sv, ":%"SVf, 
-                          SVfARG((MUTABLE_SV(progi->data->data[ ARG( o ) ]))));
-    } else if (k == LOGICAL)
-       Perl_sv_catpvf(aTHX_ sv, "[%d]", o->flags);     /* 2: embedded, otherwise 1 */
-    else if (k == FOLDCHAR)
-       Perl_sv_catpvf(aTHX_ sv, "[0x%"UVXf"]", PTR2UV(ARG(o)) );
-    else if (k == ANYOF) {
-       int i, rangestart = -1;
-       const U8 flags = ANYOF_FLAGS(o);
-       int do_sep = 0;
-
-       /* Should be synchronized with * ANYOF_ #xdefines in regcomp.h */
-       static const char * const anyofs[] = {
-           "\\w",
-           "\\W",
-           "\\s",
-           "\\S",
-           "\\d",
-           "\\D",
-           "[:alnum:]",
-           "[:^alnum:]",
-           "[:alpha:]",
-           "[:^alpha:]",
-           "[:ascii:]",
-           "[:^ascii:]",
-           "[:cntrl:]",
-           "[:^cntrl:]",
-           "[:graph:]",
-           "[:^graph:]",
-           "[:lower:]",
-           "[:^lower:]",
-           "[:print:]",
-           "[:^print:]",
-           "[:punct:]",
-           "[:^punct:]",
-           "[:upper:]",
-           "[:^upper:]",
-           "[:xdigit:]",
-           "[:^xdigit:]",
-           "[:space:]",
-           "[:^space:]",
-           "[:blank:]",
-           "[:^blank:]"
-       };
-
-       if (flags & ANYOF_LOCALE)
-           sv_catpvs(sv, "{loc}");
-       if (flags & ANYOF_LOC_NONBITMAP_FOLD)
-           sv_catpvs(sv, "{i}");
-       Perl_sv_catpvf(aTHX_ sv, "[%s", PL_colors[0]);
-       if (flags & ANYOF_INVERT)
-           sv_catpvs(sv, "^");
-       
-       /* output what the standard cp 0-255 bitmap matches */
-       for (i = 0; i <= 256; i++) {
-           if (i < 256 && ANYOF_BITMAP_TEST(o,i)) {
-               if (rangestart == -1)
-                   rangestart = i;
-           } else if (rangestart != -1) {
-               if (i <= rangestart + 3)
-                   for (; rangestart < i; rangestart++)
-                       put_byte(sv, rangestart);
-               else {
-                   put_byte(sv, rangestart);
-                   sv_catpvs(sv, "-");
-                   put_byte(sv, i - 1);
-               }
-               do_sep = 1;
-               rangestart = -1;
-           }
-       }
-        
-        EMIT_ANYOF_TEST_SEPARATOR(do_sep,sv,flags);
-        /* output any special charclass tests (used entirely under use locale) */
-       if (ANYOF_CLASS_TEST_ANY_SET(o))
-           for (i = 0; i < (int)(sizeof(anyofs)/sizeof(char*)); i++)
-               if (ANYOF_CLASS_TEST(o,i)) {
-                   sv_catpv(sv, anyofs[i]);
-                   do_sep = 1;
-               }
-        
-        EMIT_ANYOF_TEST_SEPARATOR(do_sep,sv,flags);
-        
-       if (flags & ANYOF_NON_UTF8_LATIN1_ALL) {
-           sv_catpvs(sv, "{non-utf8-latin1-all}");
-       }
-
-        /* output information about the unicode matching */
-       if (flags & ANYOF_UNICODE_ALL)
-           sv_catpvs(sv, "{unicode_all}");
-       else if (flags & ANYOF_UTF8)
-           sv_catpvs(sv, "{unicode}");
-       if (flags & ANYOF_NONBITMAP_NON_UTF8)
-           sv_catpvs(sv, "{outside bitmap}");
-
-       {
-           SV *lv;
-           SV * const sw = regclass_swash(prog, o, FALSE, &lv, 0);
-       
-           if (lv) {
-               if (sw) {
-                   U8 s[UTF8_MAXBYTES_CASE+1];
-
-                   for (i = 0; i <= 256; i++) { /* just the first 256 */
-                       uvchr_to_utf8(s, i);
-                       
-                       if (i < 256 && swash_fetch(sw, s, TRUE)) {
-                           if (rangestart == -1)
-                               rangestart = i;
-                       } else if (rangestart != -1) {
-                           if (i <= rangestart + 3)
-                               for (; rangestart < i; rangestart++) {
-                                   const U8 * const e = uvchr_to_utf8(s,rangestart);
-                                   U8 *p;
-                                   for(p = s; p < e; p++)
-                                       put_byte(sv, *p);
-                               }
-                           else {
-                               const U8 *e = uvchr_to_utf8(s,rangestart);
-                               U8 *p;
-                               for (p = s; p < e; p++)
-                                   put_byte(sv, *p);
-                               sv_catpvs(sv, "-");
-                               e = uvchr_to_utf8(s, i-1);
-                               for (p = s; p < e; p++)
-                                   put_byte(sv, *p);
-                               }
-                               rangestart = -1;
-                           }
-                       }
-                       
-                   sv_catpvs(sv, "..."); /* et cetera */
-               }
-
-               {
-                   char *s = savesvpv(lv);
-                   char * const origs = s;
-               
-                   while (*s && *s != '\n')
-                       s++;
-               
-                   if (*s == '\n') {
-                       const char * const t = ++s;
-                       
-                       while (*s) {
-                           if (*s == '\n')
-                               *s = ' ';
-                           s++;
-                       }
-                       if (s[-1] == ' ')
-                           s[-1] = 0;
-                       
-                       sv_catpv(sv, t);
-                   }
-               
-                   Safefree(origs);
-               }
-           }
-       }
-
-       Perl_sv_catpvf(aTHX_ sv, "%s]", PL_colors[1]);
-    }
-    else if (k == BRANCHJ && (OP(o) == UNLESSM || OP(o) == IFMATCH))
-       Perl_sv_catpvf(aTHX_ sv, "[%d]", -(o->flags));
-#else
-    PERL_UNUSED_CONTEXT;
-    PERL_UNUSED_ARG(sv);
-    PERL_UNUSED_ARG(o);
-    PERL_UNUSED_ARG(prog);
-#endif /* DEBUGGING */
-}
-
-SV *
-Perl_re_intuit_string(pTHX_ REGEXP * const r)
-{                              /* Assume that RE_INTUIT is set */
-    dVAR;
-    struct regexp *const prog = (struct regexp *)SvANY(r);
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_RE_INTUIT_STRING;
-    PERL_UNUSED_CONTEXT;
-
-    DEBUG_COMPILE_r(
-       {
-           const char * const s = SvPV_nolen_const(prog->check_substr
-                     ? prog->check_substr : prog->check_utf8);
-
-           if (!PL_colorset) reginitcolors();
-           PerlIO_printf(Perl_debug_log,
-                     "%sUsing REx %ssubstr:%s \"%s%.60s%s%s\"\n",
-                     PL_colors[4],
-                     prog->check_substr ? "" : "utf8 ",
-                     PL_colors[5],PL_colors[0],
-                     s,
-                     PL_colors[1],
-                     (strlen(s) > 60 ? "..." : ""));
-       } );
-
-    return prog->check_substr ? prog->check_substr : prog->check_utf8;
-}
-
-/* 
-   pregfree() 
-   
-   handles refcounting and freeing the perl core regexp structure. When 
-   it is necessary to actually free the structure the first thing it 
-   does is call the 'free' method of the regexp_engine associated to
-   the regexp, allowing the handling of the void *pprivate; member 
-   first. (This routine is not overridable by extensions, which is why 
-   the extensions free is called first.)
-   
-   See regdupe and regdupe_internal if you change anything here. 
-*/
-#ifndef PERL_IN_XSUB_RE
-void
-Perl_pregfree(pTHX_ REGEXP *r)
-{
-    SvREFCNT_dec(r);
-}
-
-void
-Perl_pregfree2(pTHX_ REGEXP *rx)
-{
-    dVAR;
-    struct regexp *const r = (struct regexp *)SvANY(rx);
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_PREGFREE2;
-
-    if (r->mother_re) {
-        ReREFCNT_dec(r->mother_re);
-    } else {
-        CALLREGFREE_PVT(rx); /* free the private data */
-        SvREFCNT_dec(RXp_PAREN_NAMES(r));
-    }        
-    if (r->substrs) {
-        SvREFCNT_dec(r->anchored_substr);
-        SvREFCNT_dec(r->anchored_utf8);
-        SvREFCNT_dec(r->float_substr);
-        SvREFCNT_dec(r->float_utf8);
-       Safefree(r->substrs);
-    }
-    RX_MATCH_COPY_FREE(rx);
-#ifdef PERL_OLD_COPY_ON_WRITE
-    SvREFCNT_dec(r->saved_copy);
-#endif
-    Safefree(r->offs);
-}
-
-/*  reg_temp_copy()
-    
-    This is a hacky workaround to the structural issue of match results
-    being stored in the regexp structure which is in turn stored in
-    PL_curpm/PL_reg_curpm. The problem is that due to qr// the pattern
-    could be PL_curpm in multiple contexts, and could require multiple
-    result sets being associated with the pattern simultaneously, such
-    as when doing a recursive match with (??{$qr})
-    
-    The solution is to make a lightweight copy of the regexp structure 
-    when a qr// is returned from the code executed by (??{$qr}) this
-    lightweight copy doesn't actually own any of its data except for
-    the starp/end and the actual regexp structure itself. 
-    
-*/    
-    
-    
-REGEXP *
-Perl_reg_temp_copy (pTHX_ REGEXP *ret_x, REGEXP *rx)
-{
-    struct regexp *ret;
-    struct regexp *const r = (struct regexp *)SvANY(rx);
-    register const I32 npar = r->nparens+1;
-
-    PERL_ARGS_ASSERT_REG_TEMP_COPY;
-
-    if (!ret_x)
-       ret_x = (REGEXP*) newSV_type(SVt_REGEXP);
-    ret = (struct regexp *)SvANY(ret_x);
-    
-    (void)ReREFCNT_inc(rx);
-    /* We can take advantage of the existing "copied buffer" mechanism in SVs
-       by pointing directly at the buffer, but flagging that the allocated
-       space in the copy is zero. As we've just done a struct copy, it's now
-       a case of zero-ing that, rather than copying the current length.  */
-    SvPV_set(ret_x, RX_WRAPPED(rx));
-    SvFLAGS(ret_x) |= SvFLAGS(rx) & (SVf_POK|SVp_POK|SVf_UTF8);
-    memcpy(&(ret->xpv_cur), &(r->xpv_cur),
-          sizeof(regexp) - STRUCT_OFFSET(regexp, xpv_cur));
-    SvLEN_set(ret_x, 0);
-    SvSTASH_set(ret_x, NULL);
-    SvMAGIC_set(ret_x, NULL);
-    Newx(ret->offs, npar, regexp_paren_pair);
-    Copy(r->offs, ret->offs, npar, regexp_paren_pair);
-    if (r->substrs) {
-        Newx(ret->substrs, 1, struct reg_substr_data);
-       StructCopy(r->substrs, ret->substrs, struct reg_substr_data);
-
-       SvREFCNT_inc_void(ret->anchored_substr);
-       SvREFCNT_inc_void(ret->anchored_utf8);
-       SvREFCNT_inc_void(ret->float_substr);
-       SvREFCNT_inc_void(ret->float_utf8);
-
-       /* check_substr and check_utf8, if non-NULL, point to either their
-          anchored or float namesakes, and don't hold a second reference.  */
-    }
-    RX_MATCH_COPIED_off(ret_x);
-#ifdef PERL_OLD_COPY_ON_WRITE
-    ret->saved_copy = NULL;
-#endif
-    ret->mother_re = rx;
-    
-    return ret_x;
-}
-#endif
-
-/* regfree_internal() 
-
-   Free the private data in a regexp. This is overloadable by 
-   extensions. Perl takes care of the regexp structure in pregfree(), 
-   this covers the *pprivate pointer which technically perl doesn't 
-   know about, however of course we have to handle the 
-   regexp_internal structure when no extension is in use. 
-   
-   Note this is called before freeing anything in the regexp 
-   structure. 
- */
-void
-Perl_regfree_internal(pTHX_ REGEXP * const rx)
-{
-    dVAR;
-    struct regexp *const r = (struct regexp *)SvANY(rx);
-    RXi_GET_DECL(r,ri);
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_REGFREE_INTERNAL;
-
-    DEBUG_COMPILE_r({
-       if (!PL_colorset)
-           reginitcolors();
-       {
-           SV *dsv= sv_newmortal();
-            RE_PV_QUOTED_DECL(s, RX_UTF8(rx),
-                dsv, RX_PRECOMP(rx), RX_PRELEN(rx), 60);
-            PerlIO_printf(Perl_debug_log,"%sFreeing REx:%s %s\n", 
-                PL_colors[4],PL_colors[5],s);
-        }
-    });
-#ifdef RE_TRACK_PATTERN_OFFSETS
-    if (ri->u.offsets)
-        Safefree(ri->u.offsets);             /* 20010421 MJD */
-#endif
-    if (ri->data) {
-       int n = ri->data->count;
-       PAD* new_comppad = NULL;
-       PAD* old_comppad;
-       PADOFFSET refcnt;
-
-       while (--n >= 0) {
-          /* If you add a ->what type here, update the comment in regcomp.h */
-           switch (ri->data->what[n]) {
-           case 'a':
-           case 's':
-           case 'S':
-           case 'u':
-               SvREFCNT_dec(MUTABLE_SV(ri->data->data[n]));
-               break;
-           case 'f':
-               Safefree(ri->data->data[n]);
-               break;
-           case 'p':
-               new_comppad = MUTABLE_AV(ri->data->data[n]);
-               break;
-           case 'o':
-               if (new_comppad == NULL)
-                   Perl_croak(aTHX_ "panic: pregfree comppad");
-               PAD_SAVE_LOCAL(old_comppad,
-                   /* Watch out for global destruction's random ordering. */
-                   (SvTYPE(new_comppad) == SVt_PVAV) ? new_comppad : NULL
-               );
-               OP_REFCNT_LOCK;
-               refcnt = OpREFCNT_dec((OP_4tree*)ri->data->data[n]);
-               OP_REFCNT_UNLOCK;
-               if (!refcnt)
-                    op_free((OP_4tree*)ri->data->data[n]);
-
-               PAD_RESTORE_LOCAL(old_comppad);
-               SvREFCNT_dec(MUTABLE_SV(new_comppad));
-               new_comppad = NULL;
-               break;
-           case 'n':
-               break;
-            case 'T':          
-                { /* Aho Corasick add-on structure for a trie node.
-                     Used in stclass optimization only */
-                    U32 refcount;
-                    reg_ac_data *aho=(reg_ac_data*)ri->data->data[n];
-                    OP_REFCNT_LOCK;
-                    refcount = --aho->refcount;
-                    OP_REFCNT_UNLOCK;
-                    if ( !refcount ) {
-                        PerlMemShared_free(aho->states);
-                        PerlMemShared_free(aho->fail);
-                        /* do this last!!!! */
-                        PerlMemShared_free(ri->data->data[n]);
-                        PerlMemShared_free(ri->regstclass);
-                    }
-                }
-                break;
-           case 't':
-               {
-                   /* trie structure. */
-                   U32 refcount;
-                   reg_trie_data *trie=(reg_trie_data*)ri->data->data[n];
-                    OP_REFCNT_LOCK;
-                    refcount = --trie->refcount;
-                    OP_REFCNT_UNLOCK;
-                    if ( !refcount ) {
-                        PerlMemShared_free(trie->charmap);
-                        PerlMemShared_free(trie->states);
-                        PerlMemShared_free(trie->trans);
-                        if (trie->bitmap)
-                            PerlMemShared_free(trie->bitmap);
-                        if (trie->jump)
-                            PerlMemShared_free(trie->jump);
-                       PerlMemShared_free(trie->wordinfo);
-                        /* do this last!!!! */
-                        PerlMemShared_free(ri->data->data[n]);
-                   }
-               }
-               break;
-           default:
-               Perl_croak(aTHX_ "panic: regfree data code '%c'", ri->data->what[n]);
-           }
-       }
-       Safefree(ri->data->what);
-       Safefree(ri->data);
-    }
-
-    Safefree(ri);
-}
-
-#define av_dup_inc(s,t)        MUTABLE_AV(sv_dup_inc((const SV *)s,t))
-#define hv_dup_inc(s,t)        MUTABLE_HV(sv_dup_inc((const SV *)s,t))
-#define SAVEPVN(p,n)   ((p) ? savepvn(p,n) : NULL)
-
-/* 
-   re_dup - duplicate a regexp. 
-   
-   This routine is expected to clone a given regexp structure. It is only
-   compiled under USE_ITHREADS.
-
-   After all of the core data stored in struct regexp is duplicated
-   the regexp_engine.dupe method is used to copy any private data
-   stored in the *pprivate pointer. This allows extensions to handle
-   any duplication it needs to do.
-
-   See pregfree() and regfree_internal() if you change anything here. 
-*/
-#if defined(USE_ITHREADS)
-#ifndef PERL_IN_XSUB_RE
-void
-Perl_re_dup_guts(pTHX_ const REGEXP *sstr, REGEXP *dstr, CLONE_PARAMS *param)
-{
-    dVAR;
-    I32 npar;
-    const struct regexp *r = (const struct regexp *)SvANY(sstr);
-    struct regexp *ret = (struct regexp *)SvANY(dstr);
-    
-    PERL_ARGS_ASSERT_RE_DUP_GUTS;
-
-    npar = r->nparens+1;
-    Newx(ret->offs, npar, regexp_paren_pair);
-    Copy(r->offs, ret->offs, npar, regexp_paren_pair);
-    if(ret->swap) {
-        /* no need to copy these */
-        Newx(ret->swap, npar, regexp_paren_pair);
-    }
-
-    if (ret->substrs) {
-       /* Do it this way to avoid reading from *r after the StructCopy().
-          That way, if any of the sv_dup_inc()s dislodge *r from the L1
-          cache, it doesn't matter.  */
-       const bool anchored = r->check_substr
-           ? r->check_substr == r->anchored_substr
-           : r->check_utf8 == r->anchored_utf8;
-        Newx(ret->substrs, 1, struct reg_substr_data);
-       StructCopy(r->substrs, ret->substrs, struct reg_substr_data);
-
-       ret->anchored_substr = sv_dup_inc(ret->anchored_substr, param);
-       ret->anchored_utf8 = sv_dup_inc(ret->anchored_utf8, param);
-       ret->float_substr = sv_dup_inc(ret->float_substr, param);
-       ret->float_utf8 = sv_dup_inc(ret->float_utf8, param);
-
-       /* check_substr and check_utf8, if non-NULL, point to either their
-          anchored or float namesakes, and don't hold a second reference.  */
-
-       if (ret->check_substr) {
-           if (anchored) {
-               assert(r->check_utf8 == r->anchored_utf8);
-               ret->check_substr = ret->anchored_substr;
-               ret->check_utf8 = ret->anchored_utf8;
-           } else {
-               assert(r->check_substr == r->float_substr);
-               assert(r->check_utf8 == r->float_utf8);
-               ret->check_substr = ret->float_substr;
-               ret->check_utf8 = ret->float_utf8;
-           }
-       } else if (ret->check_utf8) {
-           if (anchored) {
-               ret->check_utf8 = ret->anchored_utf8;
-           } else {
-               ret->check_utf8 = ret->float_utf8;
-           }
-       }
-    }
-
-    RXp_PAREN_NAMES(ret) = hv_dup_inc(RXp_PAREN_NAMES(ret), param);
-
-    if (ret->pprivate)
-       RXi_SET(ret,CALLREGDUPE_PVT(dstr,param));
-
-    if (RX_MATCH_COPIED(dstr))
-       ret->subbeg  = SAVEPVN(ret->subbeg, ret->sublen);
-    else
-       ret->subbeg = NULL;
-#ifdef PERL_OLD_COPY_ON_WRITE
-    ret->saved_copy = NULL;
-#endif
-
-    if (ret->mother_re) {
-       if (SvPVX_const(dstr) == SvPVX_const(ret->mother_re)) {
-           /* Our storage points directly to our mother regexp, but that's
-              1: a buffer in a different thread
-              2: something we no longer hold a reference on
-              so we need to copy it locally.  */
-           /* Note we need to sue SvCUR() on our mother_re, because it, in
-              turn, may well be pointing to its own mother_re.  */
-           SvPV_set(dstr, SAVEPVN(SvPVX_const(ret->mother_re),
-                                  SvCUR(ret->mother_re)+1));
-           SvLEN_set(dstr, SvCUR(ret->mother_re)+1);
-       }
-       ret->mother_re      = NULL;
-    }
-    ret->gofs = 0;
-}
-#endif /* PERL_IN_XSUB_RE */
-
-/*
-   regdupe_internal()
-   
-   This is the internal complement to regdupe() which is used to copy
-   the structure pointed to by the *pprivate pointer in the regexp.
-   This is the core version of the extension overridable cloning hook.
-   The regexp structure being duplicated will be copied by perl prior
-   to this and will be provided as the regexp *r argument, however 
-   with the /old/ structures pprivate pointer value. Thus this routine
-   may override any copying normally done by perl.
-   
-   It returns a pointer to the new regexp_internal structure.
-*/
-
-void *
-Perl_regdupe_internal(pTHX_ REGEXP * const rx, CLONE_PARAMS *param)
-{
-    dVAR;
-    struct regexp *const r = (struct regexp *)SvANY(rx);
-    regexp_internal *reti;
-    int len, npar;
-    RXi_GET_DECL(r,ri);
-
-    PERL_ARGS_ASSERT_REGDUPE_INTERNAL;
-    
-    npar = r->nparens+1;
-    len = ProgLen(ri);
-    
-    Newxc(reti, sizeof(regexp_internal) + len*sizeof(regnode), char, regexp_internal);
-    Copy(ri->program, reti->program, len+1, regnode);
-    
-
-    reti->regstclass = NULL;
-
-    if (ri->data) {
-       struct reg_data *d;
-        const int count = ri->data->count;
-       int i;
-
-       Newxc(d, sizeof(struct reg_data) + count*sizeof(void *),
-               char, struct reg_data);
-       Newx(d->what, count, U8);
-
-       d->count = count;
-       for (i = 0; i < count; i++) {
-           d->what[i] = ri->data->what[i];
-           switch (d->what[i]) {
-               /* legal options are one of: sSfpontTua
-                  see also regcomp.h and pregfree() */
-           case 'a': /* actually an AV, but the dup function is identical.  */
-           case 's':
-           case 'S':
-           case 'p': /* actually an AV, but the dup function is identical.  */
-           case 'u': /* actually an HV, but the dup function is identical.  */
-               d->data[i] = sv_dup_inc((const SV *)ri->data->data[i], param);
-               break;
-           case 'f':
-               /* This is cheating. */
-               Newx(d->data[i], 1, struct regnode_charclass_class);
-               StructCopy(ri->data->data[i], d->data[i],
-                           struct regnode_charclass_class);
-               reti->regstclass = (regnode*)d->data[i];
-               break;
-           case 'o':
-               /* Compiled op trees are readonly and in shared memory,
-                  and can thus be shared without duplication. */
-               OP_REFCNT_LOCK;
-               d->data[i] = (void*)OpREFCNT_inc((OP*)ri->data->data[i]);
-               OP_REFCNT_UNLOCK;
-               break;
-           case 'T':
-               /* Trie stclasses are readonly and can thus be shared
-                * without duplication. We free the stclass in pregfree
-                * when the corresponding reg_ac_data struct is freed.
-                */
-               reti->regstclass= ri->regstclass;
-               /* Fall through */
-           case 't':
-               OP_REFCNT_LOCK;
-               ((reg_trie_data*)ri->data->data[i])->refcount++;
-               OP_REFCNT_UNLOCK;
-               /* Fall through */
-           case 'n':
-               d->data[i] = ri->data->data[i];
-               break;
-            default:
-               Perl_croak(aTHX_ "panic: re_dup unknown data code '%c'", ri->data->what[i]);
-           }
-       }
-
-       reti->data = d;
-    }
-    else
-       reti->data = NULL;
-
-    reti->name_list_idx = ri->name_list_idx;
-
-#ifdef RE_TRACK_PATTERN_OFFSETS
-    if (ri->u.offsets) {
-        Newx(reti->u.offsets, 2*len+1, U32);
-        Copy(ri->u.offsets, reti->u.offsets, 2*len+1, U32);
-    }
-#else
-    SetProgLen(reti,len);
-#endif
-
-    return (void*)reti;
-}
-
-#endif    /* USE_ITHREADS */
-
-#ifndef PERL_IN_XSUB_RE
-
-/*
- - regnext - dig the "next" pointer out of a node
- */
-regnode *
-Perl_regnext(pTHX_ register regnode *p)
-{
-    dVAR;
-    register I32 offset;
-
-    if (!p)
-       return(NULL);
-
-    if (OP(p) > REGNODE_MAX) {         /* regnode.type is unsigned */
-       Perl_croak(aTHX_ "Corrupted regexp opcode %d > %d", (int)OP(p), (int)REGNODE_MAX);
-    }
-
-    offset = (reg_off_by_arg[OP(p)] ? ARG(p) : NEXT_OFF(p));
-    if (offset == 0)
-       return(NULL);
-
-    return(p+offset);
-}
-#endif
-
-STATIC void    
-S_re_croak2(pTHX_ const char* pat1,const char* pat2,...)
-{
-    va_list args;
-    STRLEN l1 = strlen(pat1);
-    STRLEN l2 = strlen(pat2);
-    char buf[512];
-    SV *msv;
-    const char *message;
-
-    PERL_ARGS_ASSERT_RE_CROAK2;
-
-    if (l1 > 510)
-       l1 = 510;
-    if (l1 + l2 > 510)
-       l2 = 510 - l1;
-    Copy(pat1, buf, l1 , char);
-    Copy(pat2, buf + l1, l2 , char);
-    buf[l1 + l2] = '\n';
-    buf[l1 + l2 + 1] = '\0';
-#ifdef I_STDARG
-    /* ANSI variant takes additional second argument */
-    va_start(args, pat2);
-#else
-    va_start(args);
-#endif
-    msv = vmess(buf, &args);
-    va_end(args);
-    message = SvPV_const(msv,l1);
-    if (l1 > 512)
-       l1 = 512;
-    Copy(message, buf, l1 , char);
-    buf[l1-1] = '\0';                  /* Overwrite \n */
-    Perl_croak(aTHX_ "%s", buf);
-}
-
-/* XXX Here's a total kludge.  But we need to re-enter for swash routines. */
-
-#ifndef PERL_IN_XSUB_RE
-void
-Perl_save_re_context(pTHX)
-{
-    dVAR;
-
-    struct re_save_state *state;
-
-    SAVEVPTR(PL_curcop);
-    SSGROW(SAVESTACK_ALLOC_FOR_RE_SAVE_STATE + 1);
-
-    state = (struct re_save_state *)(PL_savestack + PL_savestack_ix);
-    PL_savestack_ix += SAVESTACK_ALLOC_FOR_RE_SAVE_STATE;
-    SSPUSHUV(SAVEt_RE_STATE);
-
-    Copy(&PL_reg_state, state, 1, struct re_save_state);
-
-    PL_reg_start_tmp = 0;
-    PL_reg_start_tmpl = 0;
-    PL_reg_oldsaved = NULL;
-    PL_reg_oldsavedlen = 0;
-    PL_reg_maxiter = 0;
-    PL_reg_leftiter = 0;
-    PL_reg_poscache = NULL;
-    PL_reg_poscache_size = 0;
-#ifdef PERL_OLD_COPY_ON_WRITE
-    PL_nrs = NULL;
-#endif
-
-    /* Save $1..$n (#18107: UTF-8 s/(\w+)/uc($1)/e); AMS 20021106. */
-    if (PL_curpm) {
-       const REGEXP * const rx = PM_GETRE(PL_curpm);
-       if (rx) {
-           U32 i;
-           for (i = 1; i <= RX_NPARENS(rx); i++) {
-               char digits[TYPE_CHARS(long)];
-               const STRLEN len = my_snprintf(digits, sizeof(digits), "%lu", (long)i);
-               GV *const *const gvp
-                   = (GV**)hv_fetch(PL_defstash, digits, len, 0);
-
-               if (gvp) {
-                   GV * const gv = *gvp;
-                   if (SvTYPE(gv) == SVt_PVGV && GvSV(gv))
-                       save_scalar(gv);
-               }
-           }
-       }
-    }
-}
-#endif
-
-static void
-clear_re(pTHX_ void *r)
-{
-    dVAR;
-    ReREFCNT_dec((REGEXP *)r);
-}
-
-#ifdef DEBUGGING
-
-STATIC void
-S_put_byte(pTHX_ SV *sv, int c)
-{
-    PERL_ARGS_ASSERT_PUT_BYTE;
-
-    /* Our definition of isPRINT() ignores locales, so only bytes that are
-       not part of UTF-8 are considered printable. I assume that the same
-       holds for UTF-EBCDIC.
-       Also, code point 255 is not printable in either (it's E0 in EBCDIC,
-       which Wikipedia says:
-
-       EO, or Eight Ones, is an 8-bit EBCDIC character code represented as all
-       ones (binary 1111 1111, hexadecimal FF). It is similar, but not
-       identical, to the ASCII delete (DEL) or rubout control character.
-       ) So the old condition can be simplified to !isPRINT(c)  */
-    if (!isPRINT(c)) {
-       if (c < 256) {
-           Perl_sv_catpvf(aTHX_ sv, "\\x%02x", c);
-       }
-       else {
-           Perl_sv_catpvf(aTHX_ sv, "\\x{%x}", c);
-       }
-    }
-    else {
-       const char string = c;
-       if (c == '-' || c == ']' || c == '\\' || c == '^')
-           sv_catpvs(sv, "\\");
-       sv_catpvn(sv, &string, 1);
-    }
-}
-
-
-#define CLEAR_OPTSTART \
-    if (optstart) STMT_START { \
-           DEBUG_OPTIMISE_r(PerlIO_printf(Perl_debug_log, " (%"IVdf" nodes)\n", (IV)(node - optstart))); \
-           optstart=NULL; \
-    } STMT_END
-
-#define DUMPUNTIL(b,e) CLEAR_OPTSTART; node=dumpuntil(r,start,(b),(e),last,sv,indent+1,depth+1);
-
-STATIC const regnode *
-S_dumpuntil(pTHX_ const regexp *r, const regnode *start, const regnode *node,
-           const regnode *last, const regnode *plast, 
-           SV* sv, I32 indent, U32 depth)
-{
-    dVAR;
-    register U8 op = PSEUDO;   /* Arbitrary non-END op. */
-    register const regnode *next;
-    const regnode *optstart= NULL;
-    
-    RXi_GET_DECL(r,ri);
-    GET_RE_DEBUG_FLAGS_DECL;
-
-    PERL_ARGS_ASSERT_DUMPUNTIL;
-
-#ifdef DEBUG_DUMPUNTIL
-    PerlIO_printf(Perl_debug_log, "--- %d : %d - %d - %d\n",indent,node-start,
-        last ? last-start : 0,plast ? plast-start : 0);
-#endif
-            
-    if (plast && plast < last) 
-        last= plast;
-
-    while (PL_regkind[op] != END && (!last || node < last)) {
-       /* While that wasn't END last time... */
-       NODE_ALIGN(node);
-       op = OP(node);
-       if (op == CLOSE || op == WHILEM)
-           indent--;
-       next = regnext((regnode *)node);
-
-       /* Where, what. */
-       if (OP(node) == OPTIMIZED) {
-           if (!optstart && RE_DEBUG_FLAG(RE_DEBUG_COMPILE_OPTIMISE))
-               optstart = node;
-           else
-               goto after_print;
-       } else
-           CLEAR_OPTSTART;
-       
-       regprop(r, sv, node);
-       PerlIO_printf(Perl_debug_log, "%4"IVdf":%*s%s", (IV)(node - start),
-                     (int)(2*indent + 1), "", SvPVX_const(sv));
-        
-        if (OP(node) != OPTIMIZED) {                 
-            if (next == NULL)          /* Next ptr. */
-                PerlIO_printf(Perl_debug_log, " (0)");
-            else if (PL_regkind[(U8)op] == BRANCH && PL_regkind[OP(next)] != BRANCH )
-                PerlIO_printf(Perl_debug_log, " (FAIL)");
-            else 
-                PerlIO_printf(Perl_debug_log, " (%"IVdf")", (IV)(next - start));
-            (void)PerlIO_putc(Perl_debug_log, '\n'); 
-        }
-        
-      after_print:
-       if (PL_regkind[(U8)op] == BRANCHJ) {
-           assert(next);
-           {
-                register const regnode *nnode = (OP(next) == LONGJMP
-                                            ? regnext((regnode *)next)
-                                            : next);
-                if (last && nnode > last)
-                    nnode = last;
-                DUMPUNTIL(NEXTOPER(NEXTOPER(node)), nnode);
-           }
-       }
-       else if (PL_regkind[(U8)op] == BRANCH) {
-           assert(next);
-           DUMPUNTIL(NEXTOPER(node), next);
-       }
-       else if ( PL_regkind[(U8)op]  == TRIE ) {
-           const regnode *this_trie = node;
-           const char op = OP(node);
-            const U32 n = ARG(node);
-           const reg_ac_data * const ac = op>=AHOCORASICK ?
-               (reg_ac_data *)ri->data->data[n] :
-               NULL;
-           const reg_trie_data * const trie =
-               (reg_trie_data*)ri->data->data[op<AHOCORASICK ? n : ac->trie];
-#ifdef DEBUGGING
-           AV *const trie_words = MUTABLE_AV(ri->data->data[n + TRIE_WORDS_OFFSET]);
-#endif
-           const regnode *nextbranch= NULL;
-           I32 word_idx;
-            sv_setpvs(sv, "");
-           for (word_idx= 0; word_idx < (I32)trie->wordcount; word_idx++) {
-               SV ** const elem_ptr = av_fetch(trie_words,word_idx,0);
-               
-                PerlIO_printf(Perl_debug_log, "%*s%s ",
-                   (int)(2*(indent+3)), "",
-                    elem_ptr ? pv_pretty(sv, SvPV_nolen_const(*elem_ptr), SvCUR(*elem_ptr), 60,
-                           PL_colors[0], PL_colors[1],
-                           (SvUTF8(*elem_ptr) ? PERL_PV_ESCAPE_UNI : 0) |
-                           PERL_PV_PRETTY_ELLIPSES    |
-                           PERL_PV_PRETTY_LTGT
-                            )
-                            : "???"
-                );
-                if (trie->jump) {
-                    U16 dist= trie->jump[word_idx+1];
-                   PerlIO_printf(Perl_debug_log, "(%"UVuf")\n",
-                                 (UV)((dist ? this_trie + dist : next) - start));
-                    if (dist) {
-                        if (!nextbranch)
-                            nextbranch= this_trie + trie->jump[0];    
-                       DUMPUNTIL(this_trie + dist, nextbranch);
-                    }
-                    if (nextbranch && PL_regkind[OP(nextbranch)]==BRANCH)
-                        nextbranch= regnext((regnode *)nextbranch);
-                } else {
-                    PerlIO_printf(Perl_debug_log, "\n");
-               }
-           }
-           if (last && next > last)
-               node= last;
-           else
-               node= next;
-       }
-       else if ( op == CURLY ) {   /* "next" might be very big: optimizer */
-           DUMPUNTIL(NEXTOPER(node) + EXTRA_STEP_2ARGS,
-                    NEXTOPER(node) + EXTRA_STEP_2ARGS + 1);
-       }
-       else if (PL_regkind[(U8)op] == CURLY && op != CURLYX) {
-           assert(next);
-           DUMPUNTIL(NEXTOPER(node) + EXTRA_STEP_2ARGS, next);
-       }
-       else if ( op == PLUS || op == STAR) {
-           DUMPUNTIL(NEXTOPER(node), NEXTOPER(node) + 1);
-       }
-       else if (PL_regkind[(U8)op] == ANYOF) {
-           /* arglen 1 + class block */
-           node += 1 + ((ANYOF_FLAGS(node) & ANYOF_CLASS)
-                   ? ANYOF_CLASS_SKIP : ANYOF_SKIP);
-           node = NEXTOPER(node);
-       }
-       else if (PL_regkind[(U8)op] == EXACT) {
-            /* Literal string, where present. */
-           node += NODE_SZ_STR(node) - 1;
-           node = NEXTOPER(node);
-       }
-       else {
-           node = NEXTOPER(node);
-           node += regarglen[(U8)op];
-       }
-       if (op == CURLYX || op == OPEN)
-           indent++;
-    }
-    CLEAR_OPTSTART;
-#ifdef DEBUG_DUMPUNTIL    
-    PerlIO_printf(Perl_debug_log, "--- %d\n", (int)indent);
-#endif
-    return node;
-}
-
-#endif /* DEBUGGING */
-
-/*
- * Local variables:
- * c-indentation-style: bsd
- * c-basic-offset: 4
- * indent-tabs-mode: t
- * End:
- *
- * ex: set ts=8 sts=4 sw=4 noet:
- */