+ dupsv = sv_dup(sv, ¶m);
+
+ if (stashes) {
+ av_undef(stashes);
+ SvREFCNT_dec(stashes);
+ }
+
+ return SvREFCNT_inc(dupsv);
+}
+
+STATIC void rep_ptable_clone(pTHX_ ptable_ent *ent, void *ud_) {
+ my_cxt_t *ud = ud_;
+ rep_hint_t *h1 = ent->val;
+ rep_hint_t *h2;
+
+ if (ud->owner == aTHX)
+ return;
+
+ h2 = PerlMemShared_malloc(sizeof *h2);
+ h2->comp = rep_clone(h1->comp, ud->owner);
+ SvREFCNT_inc(h2->comp);
+ h2->exec = rep_clone(h1->exec, ud->owner);
+ SvREFCNT_inc(h2->exec);
+#if REP_WORKAROUND_REQUIRE_PROPAGATION
+ h2->requires = h1->requires;
+#endif
+
+ ptable_store(ud->tbl, ent->key, h2);
+}
+
+STATIC void rep_thread_cleanup(pTHX_ void *);
+
+STATIC void rep_thread_cleanup(pTHX_ void *ud) {
+ int *level = ud;
+
+ if (*level) {
+ *level = 0;
+ LEAVE;
+ SAVEDESTRUCTOR_X(rep_thread_cleanup, level);
+ ENTER;
+ } else {
+ dMY_CXT;
+ PerlMemShared_free(level);
+ ptable_free(MY_CXT.tbl);
+ }
+}
+
+#endif /* REP_THREADSAFE */
+
+STATIC SV *rep_validate_callback(SV *code) {
+ if (!SvROK(code))
+ return NULL;
+
+ code = SvRV(code);
+ if (SvTYPE(code) < SVt_PVCV)
+ return NULL;
+
+ return SvREFCNT_inc_simple_NN(code);
+}
+
+STATIC SV *rep_tag(pTHX_ SV *comp, SV *exec) {
+#define rep_tag(C, E) rep_tag(aTHX_ (C), (E))
+ rep_hint_t *h;
+ dMY_CXT;
+
+ h = PerlMemShared_malloc(sizeof *h);
+
+ h->comp = rep_validate_callback(comp);
+ h->exec = rep_validate_callback(exec);
+
+#if REP_WORKAROUND_REQUIRE_PROPAGATION
+ {
+ const PERL_SI *si;
+ I32 requires = 0;
+
+ for (si = PL_curstackinfo; si; si = si->si_prev) {
+ I32 cxix;
+
+ for (cxix = si->si_cxix; cxix >= 0; --cxix) {
+ const PERL_CONTEXT *cx = si->si_cxstack + cxix;
+
+ if (CxTYPE(cx) == CXt_EVAL && cx->blk_eval.old_op_type == OP_REQUIRE)
+ ++requires;
+ }
+ }
+
+ h->requires = requires;
+ }
+#endif
+
+#if REP_THREADSAFE
+ /* We only need for the key to be an unique tag for looking up the value later.
+ * Allocated memory provides convenient unique identifiers, so that's why we
+ * use the hint as the key itself. */
+ ptable_store(MY_CXT.tbl, h, h);
+#endif /* REP_THREADSAFE */
+
+ return newSViv(PTR2IV(h));
+}
+
+STATIC const rep_hint_t *rep_detag(pTHX_ const SV *hint) {
+#define rep_detag(H) rep_detag(aTHX_ (H))
+ rep_hint_t *h;
+ dMY_CXT;
+
+ if (!(hint && SvIOK(hint)))
+ return NULL;
+
+ h = INT2PTR(rep_hint_t *, SvIVX(hint));
+#if REP_THREADSAFE
+ h = ptable_fetch(MY_CXT.tbl, h);
+#endif /* REP_THREADSAFE */
+
+#if REP_WORKAROUND_REQUIRE_PROPAGATION
+ {
+ const PERL_SI *si;
+ I32 requires = 0;
+
+ for (si = PL_curstackinfo; si; si = si->si_prev) {
+ I32 cxix;
+
+ for (cxix = si->si_cxix; cxix >= 0; --cxix) {
+ const PERL_CONTEXT *cx = si->si_cxstack + cxix;
+
+ if (CxTYPE(cx) == CXt_EVAL && cx->blk_eval.old_op_type == OP_REQUIRE
+ && ++requires > h->requires)
+ return NULL;
+ }
+ }
+ }
+#endif
+
+ return h;
+}
+
+STATIC U32 rep_hash = 0;
+
+STATIC const rep_hint_t *rep_hint(pTHX) {
+#define rep_hint() rep_hint(aTHX)
+ SV *hint;
+
+ /* We already require 5.9.5 for the regexp engine API. */
+ hint = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
+ NULL,
+ __PACKAGE__, __PACKAGE_LEN__,
+ 0,
+ rep_hash);
+
+ return rep_detag(hint);