OP proxy_op;
} su_unwind_storage;
+/* --- yield() global storage ---------------------------------------------- */
+
+typedef struct {
+ I32 cxix;
+ I32 items;
+ SV **savesp;
+ UNOP leave_op;
+ OP proxy_op;
+} su_yield_storage;
+
/* --- uplevel() data tokens and global storage ---------------------------- */
#define SU_UPLEVEL_HIJACKS_RUNOPS SU_HAS_PERL(5, 8, 0)
typedef struct {
char *stack_placeholder;
su_unwind_storage unwind_storage;
+ su_yield_storage yield_storage;
su_uplevel_storage uplevel_storage;
su_uid_storage uid_storage;
} my_cxt_t;
/* --- Pop a context back -------------------------------------------------- */
-#if SU_DEBUG
-# ifdef DEBUGGING
-# define SU_CXNAME(C) PL_block_type[CxTYPE(C)]
-# else
-# define SU_CXNAME(C) "XXX"
-# endif
+#if SU_DEBUG && defined(DEBUGGING)
+# define SU_CXNAME(C) PL_block_type[CxTYPE(C)]
+#else
+# define SU_CXNAME(C) "XXX"
#endif
STATIC void su_pop(pTHX_ void *ud) {
PL_op = &(MY_CXT.unwind_storage.proxy_op);
}
+/* --- Yield --------------------------------------------------------------- */
+
+#if SU_HAS_PERL(5, 10, 0)
+# define SU_RETOP_SUB(C) ((C)->blk_sub.retop)
+# define SU_RETOP_EVAL(C) ((C)->blk_eval.retop)
+# define SU_RETOP_LOOP(C) ((C)->blk_loop.my_op->op_lastop->op_next)
+# define SU_RETOP_GIVEN(C) ((C)->blk_givwhen.leave_op->op_next)
+#else
+# define SU_RETOP_SUB(C) ((C)->blk_oldretsp > 0 ? PL_retstack[(C)->blk_oldretsp - 1] : NULL)
+# define SU_RETOP_EVAL(C) SU_RETOP_SUB(C)
+# define SU_RETOP_LOOP(C) ((C)->blk_loop.last_op->op_next)
+#endif
+
+STATIC void su_yield(pTHX_ void *ud_) {
+ dMY_CXT;
+ PERL_CONTEXT *cx;
+ I32 cxix = MY_CXT.yield_storage.cxix;
+ I32 items = MY_CXT.yield_storage.items - 1;
+ SV **savesp = MY_CXT.yield_storage.savesp;
+ opcode type = OP_NULL;
+ U8 flags = 0;
+ OP *next;
+
+ PERL_UNUSED_VAR(ud_);
+
+ if (savesp)
+ PL_stack_sp = savesp;
+
+ cx = cxstack + cxix;
+ switch (CxTYPE(cx)) {
+ case CXt_BLOCK: {
+ I32 i, cur = cxstack_ix, n = 1;
+ OP *o = NULL;
+ /* Is this actually a given/when block? This may occur only when yield was
+ * called with HERE (or nothing) as the context. */
+#if SU_HAS_PERL(5, 10, 0)
+ if (cxix > 0) {
+ PERL_CONTEXT *prev = cx - 1;
+ U8 type = CxTYPE(prev);
+ if ((type == CXt_GIVEN || type == CXt_WHEN)
+ && (prev->blk_oldcop == cx->blk_oldcop)) {
+ cxix--;
+ cx = prev;
+ if (type == CXt_GIVEN)
+ goto cxt_given;
+ else
+ goto cxt_when;
+ }
+ }
+#endif
+ type = OP_LEAVE;
+ next = NULL;
+ /* Bare blocks (that appear as do { ... } blocks, map { ... } blocks or
+ * constant folded blcoks) don't need to save the op to return to anywhere
+ * since 'last' isn't supposed to work inside them. So we climb higher in
+ * the context stack until we reach a context that has a return op (i.e. a
+ * sub, an eval, a format or a real loop), recording how many blocks we
+ * crossed. Then we follow the op_next chain until we get to the leave op
+ * that closes the original block, which we are assured to reach since
+ * everything is static (the blocks we have crossed cannot be evals or
+ * subroutine calls). */
+ for (i = cxix + 1; i <= cur; ++i) {
+ PERL_CONTEXT *cx2 = cxstack + i;
+ switch (CxTYPE(cx2)) {
+ case CXt_BLOCK:
+ ++n;
+ break;
+ case CXt_SUB:
+ case CXt_FORMAT:
+ o = SU_RETOP_SUB(cx2);
+ break;
+ case CXt_EVAL:
+ o = SU_RETOP_EVAL(cx2);
+ break;
+#if SU_HAS_PERL(5, 11, 0)
+ case CXt_LOOP_FOR:
+ case CXt_LOOP_PLAIN:
+ case CXt_LOOP_LAZYSV:
+ case CXt_LOOP_LAZYIV:
+#else
+ case CXt_LOOP:
+#endif
+ o = SU_RETOP_LOOP(cx2);
+ break;
+ }
+ if (o)
+ break;
+ }
+ if (!o)
+ o = PL_op;
+ while (n && o) {
+ /* We may find other enter/leave blocks on our way to the matching leave.
+ * Make sure the depth is incremented/decremented appropriately. */
+ if (o->op_type == OP_ENTER) {
+ ++n;
+ } else if (o->op_type == OP_LEAVE) {
+ --n;
+ if (!n) {
+ next = o->op_next;
+ break;
+ }
+ }
+ o = o->op_next;
+ }
+ break;
+ }
+ case CXt_SUB:
+ case CXt_FORMAT:
+ type = OP_LEAVESUB;
+ next = SU_RETOP_SUB(cx);
+ break;
+ case CXt_EVAL:
+ type = CxTRYBLOCK(cx) ? OP_LEAVETRY : OP_LEAVEEVAL;
+ next = SU_RETOP_EVAL(cx);
+ break;
+#if SU_HAS_PERL(5, 11, 0)
+ case CXt_LOOP_FOR:
+ case CXt_LOOP_PLAIN:
+ case CXt_LOOP_LAZYSV:
+ case CXt_LOOP_LAZYIV:
+#else
+ case CXt_LOOP:
+#endif
+ type = OP_LEAVELOOP;
+ next = SU_RETOP_LOOP(cx);
+ break;
+#if SU_HAS_PERL(5, 10, 0)
+ case CXt_GIVEN:
+cxt_given:
+ type = OP_LEAVEGIVEN;
+ next = SU_RETOP_GIVEN(cx);
+ break;
+ case CXt_WHEN:
+cxt_when:
+#if SU_HAS_PERL(5, 15, 1)
+ type = OP_LEAVEWHEN;
+#else
+ type = OP_BREAK;
+ flags |= OPf_SPECIAL;
+#endif
+ next = NULL;
+ break;
+#endif
+ case CXt_SUBST:
+ croak("yield() cannot target a substitution context");
+ break;
+ default:
+ croak("yield() don't know how to leave a %s context", SU_CXNAME(cxstack + cxix));
+ break;
+ }
+
+ if (cxstack_ix > cxix)
+ dounwind(cxix);
+
+ /* Hide the level */
+ if (items >= 0)
+ PL_stack_sp--;
+ else
+ items = 0;
+
+ /* Copy the arguments passed to yield() where the leave op expects to find
+ * them. */
+ if (items)
+ Move(PL_stack_sp - items + 1, PL_stack_base + cx->blk_oldsp + 1, items, SV *);
+ PL_stack_sp = PL_stack_base + cx->blk_oldsp + items;
+
+ flags |= OP_GIMME_REVERSE(cx->blk_gimme);
+
+ MY_CXT.yield_storage.leave_op.op_type = type;
+ MY_CXT.yield_storage.leave_op.op_ppaddr = PL_ppaddr[type];
+ MY_CXT.yield_storage.leave_op.op_flags = flags;
+ MY_CXT.yield_storage.leave_op.op_next = next;
+
+ PL_op = (OP *) &(MY_CXT.yield_storage.leave_op);
+ PL_op = PL_op->op_ppaddr(aTHX);
+
+ MY_CXT.yield_storage.proxy_op.op_next = PL_op;
+ PL_op = &(MY_CXT.yield_storage.proxy_op);
+}
+
/* --- Uplevel ------------------------------------------------------------- */
#define SU_UPLEVEL_SAVE(f, t) STMT_START { sud->old_##f = PL_##f; PL_##f = (t); } STMT_END
MY_CXT.unwind_storage.proxy_op.op_type = OP_STUB;
MY_CXT.unwind_storage.proxy_op.op_ppaddr = NULL;
+ Zero(&(MY_CXT.yield_storage.leave_op), 1, UNOP);
+ MY_CXT.yield_storage.leave_op.op_type = OP_STUB;
+ MY_CXT.yield_storage.leave_op.op_ppaddr = NULL;
+
+ Zero(&(MY_CXT.yield_storage.proxy_op), 1, OP);
+ MY_CXT.yield_storage.proxy_op.op_type = OP_STUB;
+ MY_CXT.yield_storage.proxy_op.op_ppaddr = NULL;
+
MY_CXT.uplevel_storage.top = NULL;
MY_CXT.uplevel_storage.root = NULL;
MY_CXT.uplevel_storage.count = 0;
croak("Can't return outside a subroutine");
}
+XS(XS_Scope__Upper_yield); /* prototype to pass -Wmissing-prototypes */
+
+XS(XS_Scope__Upper_yield) {
+#ifdef dVAR
+ dVAR; dXSARGS;
+#else
+ dXSARGS;
+#endif
+ dMY_CXT;
+ I32 cxix;
+
+ PERL_UNUSED_VAR(cv); /* -W */
+ PERL_UNUSED_VAR(ax); /* -Wall */
+
+ SU_GET_CONTEXT(0, items - 1, su_context_here());
+ MY_CXT.yield_storage.cxix = cxix;
+ MY_CXT.yield_storage.items = items;
+ /* See XS_Scope__Upper_unwind */
+ if (GIMME_V == G_SCALAR) {
+ MY_CXT.yield_storage.savesp = PL_stack_sp;
+ PL_stack_sp = PL_stack_base + PL_markstack_ptr[1] + 1;
+ } else {
+ MY_CXT.yield_storage.savesp = NULL;
+ }
+ SAVEDESTRUCTOR_X(su_yield, NULL);
+ return;
+}
+
MODULE = Scope::Upper PACKAGE = Scope::Upper
PROTOTYPES: ENABLE
newCONSTSUB(stash, "SU_THREADSAFE", newSVuv(SU_THREADSAFE));
newXSproto("Scope::Upper::unwind", XS_Scope__Upper_unwind, file, NULL);
+ newXSproto("Scope::Upper::yield", XS_Scope__Upper_yield, file, NULL);
su_setup();
}
projects / perl / modules / Scope-Upper.git / blobdiff