3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4 * 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
12 * Then he heard Merry change the note, and up went the Horn-cry of Buckland,
15 * Awake! Awake! Fear, Fire, Foes! Awake!
18 * [p.1007 of _The Lord of the Rings_, VI/viii: "The Scouring of the Shire"]
21 /* This file contains 'hot' pp ("push/pop") functions that
22 * execute the opcodes that make up a perl program. A typical pp function
23 * expects to find its arguments on the stack, and usually pushes its
24 * results onto the stack, hence the 'pp' terminology. Each OP structure
25 * contains a pointer to the relevant pp_foo() function.
27 * By 'hot', we mean common ops whose execution speed is critical.
28 * By gathering them together into a single file, we encourage
29 * CPU cache hits on hot code. Also it could be taken as a warning not to
30 * change any code in this file unless you're sure it won't affect
35 #define PERL_IN_PP_HOT_C
49 PL_curcop = (COP*)PL_op;
50 TAINT_NOT; /* Each statement is presumed innocent */
51 PL_stack_sp = PL_stack_base + CX_CUR()->blk_oldsp;
61 if (UNLIKELY(PL_op->op_private & OPpLVAL_INTRO))
62 PUSHs(save_scalar(cGVOP_gv));
64 PUSHs(GvSVn(cGVOP_gv));
69 /* also used for: pp_lineseq() pp_regcmaybe() pp_scalar() pp_scope() */
76 /* This is sometimes called directly by pp_coreargs, pp_grepstart and
80 PUSHMARK(PL_stack_sp);
91 /* no PUTBACK, SETs doesn't inc/dec SP */
98 XPUSHs(MUTABLE_SV(cGVOP_gv));
103 /* also used for: pp_andassign() */
109 /* SP is not used to remove a variable that is saved across the
110 sv_2bool_flags call in SvTRUE_NN, if a RISC/CISC or low/high machine
111 register or load/store vs direct mem ops macro is introduced, this
112 should be a define block between direct PL_stack_sp and dSP operations,
113 presently, using PL_stack_sp is bias towards CISC cpus */
114 SV * const sv = *PL_stack_sp;
118 if (PL_op->op_type == OP_AND)
120 return cLOGOP->op_other;
128 /* sassign keeps its args in the optree traditionally backwards.
129 So we pop them differently.
131 SV *left = POPs; SV *right = TOPs;
133 if (PL_op->op_private & OPpASSIGN_BACKWARDS) { /* {or,and,dor}assign */
134 SV * const temp = left;
135 left = right; right = temp;
137 assert(TAINTING_get || !TAINT_get);
138 if (UNLIKELY(TAINT_get) && !SvTAINTED(right))
140 if (UNLIKELY(PL_op->op_private & OPpASSIGN_CV_TO_GV)) {
142 SV * const cv = SvRV(right);
143 const U32 cv_type = SvTYPE(cv);
144 const bool is_gv = isGV_with_GP(left);
145 const bool got_coderef = cv_type == SVt_PVCV || cv_type == SVt_PVFM;
151 /* Can do the optimisation if left (LVALUE) is not a typeglob,
152 right (RVALUE) is a reference to something, and we're in void
154 if (!got_coderef && !is_gv && GIMME_V == G_VOID) {
155 /* Is the target symbol table currently empty? */
156 GV * const gv = gv_fetchsv_nomg(left, GV_NOINIT, SVt_PVGV);
157 if (SvTYPE(gv) != SVt_PVGV && !SvOK(gv)) {
158 /* Good. Create a new proxy constant subroutine in the target.
159 The gv becomes a(nother) reference to the constant. */
160 SV *const value = SvRV(cv);
162 SvUPGRADE(MUTABLE_SV(gv), SVt_IV);
163 SvPCS_IMPORTED_on(gv);
165 SvREFCNT_inc_simple_void(value);
171 /* Need to fix things up. */
173 /* Need to fix GV. */
174 left = MUTABLE_SV(gv_fetchsv_nomg(left,GV_ADD, SVt_PVGV));
178 /* We've been returned a constant rather than a full subroutine,
179 but they expect a subroutine reference to apply. */
181 ENTER_with_name("sassign_coderef");
182 SvREFCNT_inc_void(SvRV(cv));
183 /* newCONSTSUB takes a reference count on the passed in SV
184 from us. We set the name to NULL, otherwise we get into
185 all sorts of fun as the reference to our new sub is
186 donated to the GV that we're about to assign to.
188 SvRV_set(right, MUTABLE_SV(newCONSTSUB(GvSTASH(left), NULL,
191 LEAVE_with_name("sassign_coderef");
193 /* What can happen for the corner case *{"BONK"} = \&{"BONK"};
195 First: ops for \&{"BONK"}; return us the constant in the
197 Second: ops for *{"BONK"} cause that symbol table entry
198 (and our reference to it) to be upgraded from RV
200 Thirdly: We get here. cv is actually PVGV now, and its
201 GvCV() is actually the subroutine we're looking for
203 So change the reference so that it points to the subroutine
204 of that typeglob, as that's what they were after all along.
206 GV *const upgraded = MUTABLE_GV(cv);
207 CV *const source = GvCV(upgraded);
210 assert(CvFLAGS(source) & CVf_CONST);
212 SvREFCNT_inc_simple_void_NN(source);
213 SvREFCNT_dec_NN(upgraded);
214 SvRV_set(right, MUTABLE_SV(source));
220 UNLIKELY(SvTEMP(left)) && !SvSMAGICAL(left) && SvREFCNT(left) == 1 &&
221 (!isGV_with_GP(left) || SvFAKE(left)) && ckWARN(WARN_MISC)
224 packWARN(WARN_MISC), "Useless assignment to a temporary"
226 SvSetMagicSV(left, right);
238 RETURNOP(SvTRUE_NN(sv) ? cLOGOP->op_other : cLOGOP->op_next);
245 TAINT_NOT; /* Each statement is presumed innocent */
247 PL_stack_sp = PL_stack_base + cx->blk_oldsp;
249 if (!(PL_op->op_flags & OPf_SPECIAL)) {
250 assert(CxTYPE(cx) == CXt_BLOCK || CxTYPE_is_LOOP(cx));
257 /* The main body of pp_concat, not including the magic/overload and
259 * It does targ = left . right.
260 * Moved into a separate function so that pp_multiconcat() can use it
264 PERL_STATIC_INLINE void
265 S_do_concat(pTHX_ SV *left, SV *right, SV *targ, U8 targmy)
269 const char *rpv = NULL;
271 bool rcopied = FALSE;
273 if (TARG == right && right != left) { /* $r = $l.$r */
274 rpv = SvPV_nomg_const(right, rlen);
275 rbyte = !DO_UTF8(right);
276 right = newSVpvn_flags(rpv, rlen, SVs_TEMP);
277 rpv = SvPV_const(right, rlen); /* no point setting UTF-8 here */
281 if (TARG != left) { /* not $l .= $r */
283 const char* const lpv = SvPV_nomg_const(left, llen);
284 lbyte = !DO_UTF8(left);
285 sv_setpvn(TARG, lpv, llen);
291 else { /* $l .= $r and left == TARG */
293 if ((left == right /* $l .= $l */
294 || targmy) /* $l = $l . $r */
295 && ckWARN(WARN_UNINITIALIZED)
301 SvPV_force_nomg_nolen(left);
303 lbyte = !DO_UTF8(left);
309 rpv = SvPV_nomg_const(right, rlen);
310 rbyte = !DO_UTF8(right);
312 if (lbyte != rbyte) {
314 sv_utf8_upgrade_nomg(TARG);
317 right = newSVpvn_flags(rpv, rlen, SVs_TEMP);
318 sv_utf8_upgrade_nomg(right);
319 rpv = SvPV_nomg_const(right, rlen);
322 sv_catpvn_nomg(TARG, rpv, rlen);
329 dSP; dATARGET; tryAMAGICbin_MG(concat_amg, AMGf_assign);
332 S_do_concat(aTHX_ left, right, targ, PL_op->op_private & OPpTARGET_MY);
341 Concatenate one or more args, possibly interleaved with constant string
342 segments. The result may be assigned to, or appended to, a variable or
345 Several op_flags and/or op_private bits indicate what the target is, and
346 whether it's appended to. Valid permutations are:
348 - (PADTMP) = (A.B.C....)
349 OPpTARGET_MY $lex = (A.B.C....)
350 OPpTARGET_MY,OPpLVAL_INTRO my $lex = (A.B.C....)
351 OPpTARGET_MY,OPpMULTICONCAT_APPEND $lex .= (A.B.C....)
352 OPf_STACKED expr = (A.B.C....)
353 OPf_STACKED,OPpMULTICONCAT_APPEND expr .= (A.B.C....)
355 Other combinations like (A.B).(C.D) are not optimised into a multiconcat
356 op, as it's too hard to get the correct ordering of ties, overload etc.
360 OPpMULTICONCAT_FAKE: not a real concat, instead an optimised
361 sprintf "...%s...". Don't call '.'
362 overloading: only use '""' overloading.
364 OPpMULTICONCAT_STRINGIFY: the RHS was of the form
365 "...$a...$b..." rather than
366 "..." . $a . "..." . $b . "..."
368 An OP_MULTICONCAT is of type UNOP_AUX. The fixed slots of the aux array are
369 defined with PERL_MULTICONCAT_IX_FOO constants, where:
372 FOO index description
373 -------- ----- ----------------------------------
374 NARGS 0 number of arguments
375 PLAIN_PV 1 non-utf8 constant string
376 PLAIN_LEN 2 non-utf8 constant string length
377 UTF8_PV 3 utf8 constant string
378 UTF8_LEN 4 utf8 constant string length
379 LENGTHS 5 first of nargs+1 const segment lengths
381 The idea is that a general string concatenation will have a fixed (known
382 at compile time) number of variable args, interspersed with constant
383 strings, e.g. "a=$a b=$b\n"
385 All the constant string segments "a=", " b=" and "\n" are stored as a
386 single string "a= b=\n", pointed to from the PLAIN_PV/UTF8_PV slot, along
387 with a series of segment lengths: e.g. 2,3,1. In the case where the
388 constant string is plain but has a different utf8 representation, both
389 variants are stored, and two sets of (nargs+1) segments lengths are stored
390 in the slots beginning at PERL_MULTICONCAT_IX_LENGTHS.
392 A segment length of -1 indicates that there is no constant string at that
393 point; this distinguishes between e.g. ($a . $b) and ($a . "" . $b), which
394 have differing overloading behaviour.
401 SV *targ; /* The SV to be assigned or appended to */
402 char *targ_pv; /* where within SvPVX(targ) we're writing to */
403 STRLEN targ_len; /* SvCUR(targ) */
404 SV **toparg; /* the highest arg position on the stack */
405 UNOP_AUX_item *aux; /* PL_op->op_aux buffer */
406 UNOP_AUX_item *const_lens; /* the segment length array part of aux */
407 const char *const_pv; /* the current segment of the const string buf */
408 SSize_t nargs; /* how many args were expected */
409 SSize_t stack_adj; /* how much to adjust SP on return */
410 STRLEN grow; /* final size of destination string (targ) */
411 UV targ_count; /* how many times targ has appeared on the RHS */
412 bool is_append; /* OPpMULTICONCAT_APPEND flag is set */
413 bool slow_concat; /* args too complex for quick concat */
414 U32 dst_utf8; /* the result will be utf8 (indicate this with
415 SVf_UTF8 in a U32, rather than using bool,
416 for ease of testing and setting) */
417 /* for each arg, holds the result of an SvPV() call */
418 struct multiconcat_svpv {
422 *targ_chain, /* chain of slots where targ has appeared on RHS */
423 *svpv_p, /* ptr for looping through svpv_buf */
424 *svpv_base, /* first slot (may be greater than svpv_buf), */
425 *svpv_end, /* and slot after highest result so far, of: */
426 svpv_buf[PERL_MULTICONCAT_MAXARG]; /* buf for storing SvPV() results */
428 aux = cUNOP_AUXx(PL_op)->op_aux;
429 stack_adj = nargs = aux[PERL_MULTICONCAT_IX_NARGS].ssize;
430 is_append = cBOOL(PL_op->op_private & OPpMULTICONCAT_APPEND);
432 /* get targ from the stack or pad */
434 if (PL_op->op_flags & OPf_STACKED) {
436 /* for 'expr .= ...', expr is the bottom item on the stack */
441 /* for 'expr = ...', expr is the top item on the stack */
445 SV **svp = &(PAD_SVl(PL_op->op_targ));
447 if (PL_op->op_private & OPpLVAL_INTRO) {
448 assert(PL_op->op_private & OPpTARGET_MY);
452 /* $lex .= "const" doesn't cause anything to be pushed */
458 grow = 1; /* allow for '\0' at minimum */
463 /* only utf8 variants of the const strings? */
464 dst_utf8 = aux[PERL_MULTICONCAT_IX_PLAIN_PV].pv ? 0 : SVf_UTF8;
467 /* --------------------------------------------------------------
470 * stringify (i.e. SvPV()) every arg and store the resultant pv/len/utf8
471 * triplets in svpv_buf[]. Also increment 'grow' by the args' lengths.
473 * utf8 is indicated by storing a negative length.
475 * Where an arg is actually targ, the stringification is deferred:
476 * the length is set to 0, and the slot is added to targ_chain.
478 * If a magic, overloaded, or otherwise weird arg is found, which
479 * might have side effects when stringified, the loop is abandoned and
480 * we goto a code block where a more basic 'emulate calling
481 * pp_cpncat() on each arg in turn' is done.
484 for (; SP <= toparg; SP++, svpv_end++) {
489 assert(svpv_end - svpv_buf < PERL_MULTICONCAT_MAXARG);
493 /* this if/else chain is arranged so that common/simple cases
494 * take few conditionals */
496 if (LIKELY((SvFLAGS(sv) & (SVs_GMG|SVf_ROK|SVf_POK)) == SVf_POK)) {
497 /* common case: sv is a simple non-magical PV */
499 /* targ appears on RHS.
500 * Delay storing PV pointer; instead, add slot to targ_chain
501 * so it can be populated later, after targ has been grown and
502 * we know its final SvPVX() address.
505 svpv_end->len = 0; /* zerojng here means we can skip
506 updating later if targ_len == 0 */
507 svpv_end->pv = (char*)targ_chain;
508 targ_chain = svpv_end;
514 svpv_end->pv = SvPVX(sv);
516 else if (UNLIKELY(SvFLAGS(sv) & (SVs_GMG|SVf_ROK)))
517 /* may have side effects: tie, overload etc.
518 * Abandon 'stringify everything first' and handle
519 * args in strict order. Note that already-stringified args
520 * will be reprocessed, which is safe because the each first
521 * stringification would have been idempotent.
524 else if (SvNIOK(sv)) {
527 /* stringify general valid scalar */
528 svpv_end->pv = sv_2pv_flags(sv, &len, 0);
530 else if (!SvOK(sv)) {
531 if (ckWARN(WARN_UNINITIALIZED))
532 /* an undef value in the presence of warnings may trigger
535 svpv_end->pv = (char*)"";
539 goto do_magical; /* something weird */
541 utf8 = (SvFLAGS(sv) & SVf_UTF8);
543 ASSUME(len < SSize_t_MAX);
544 svpv_end->len = utf8 ? -(SSize_t)len : (SSize_t)len;
548 /* --------------------------------------------------------------
553 * if targ appears on the RHS or is appended to, force stringify it;
554 * otherwise set it to "". Then set targ_len.
558 /* abandon quick route if using targ might have side effects */
559 if (UNLIKELY(SvFLAGS(targ) & (SVs_GMG|SVf_ROK)))
565 SvPV_force_nomg_nolen(targ);
566 targ_utf8 = SvFLAGS(targ) & SVf_UTF8;
567 if (UNLIKELY(dst_utf8 & ~targ_utf8)) {
568 if (LIKELY(!IN_BYTES))
569 sv_utf8_upgrade_nomg(targ);
572 dst_utf8 |= targ_utf8;
574 targ_len = SvCUR(targ);
575 grow += targ_len * (targ_count + is_append);
578 else if (ckWARN(WARN_UNINITIALIZED))
579 /* warning might have side effects */
581 /* the undef targ will be silently SvPVCLEAR()ed below */
583 else if (UNLIKELY(SvTYPE(targ) >= SVt_REGEXP)) {
584 /* Assigning to some weird LHS type. Don't force the LHS to be an
585 * empty string; instead, do things 'long hand' by using the
586 * overload code path, which concats to a TEMP sv and does
587 * sv_catsv() calls rather than COPY()s. This ensures that even
588 * bizarre code like this doesn't break or crash:
590 * (which makes the 'F' typeglob an alias to the
591 * '*main::F*main::F' typeglob).
596 /* targ was found on RHS.
597 * Force stringify it, using the same code as the append branch
598 * above, except that we don't need the magic/overload/undef
599 * checks as these will already have been done in the phase 1
604 /* unrolled SvPVCLEAR() - mostly: no need to grow or set SvCUR() to 0;
605 * those will be done later. */
606 SV_CHECK_THINKFIRST_COW_DROP(targ);
607 SvUPGRADE(targ, SVt_PV);
608 SvFLAGS(targ) &= ~(SVf_OK|SVf_IVisUV|SVf_UTF8);
609 SvFLAGS(targ) |= (SVf_POK|SVp_POK|dst_utf8);
613 /* --------------------------------------------------------------
616 * UTF-8 tweaks and grow targ:
618 * Now that we know the length and utf8-ness of both the targ and
619 * args, grow targ to the size needed to accumulate all the args, based
620 * on whether targ appears on the RHS, whether we're appending, and
621 * whether any non-utf8 args expand in size if converted to utf8.
623 * For the latter, if dst_utf8 we scan non-utf8 args looking for
624 * variant chars, and adjust the svpv->len value of those args to the
625 * utf8 size and negate it to flag them. At the same time we un-negate
626 * the lens of any utf8 args since after this phase we no longer care
627 * whether an arg is utf8 or not.
629 * Finally, initialise const_lens and const_pv based on utf8ness.
630 * Note that there are 3 permutations:
632 * * If the constant string is invariant whether utf8 or not (e.g. "abc"),
633 * then aux[PERL_MULTICONCAT_IX_PLAIN_PV/LEN] are the same as
634 * aux[PERL_MULTICONCAT_IX_UTF8_PV/LEN] and there is one set of
637 * * If the string is fully utf8, e.g. "\x{100}", then
638 * aux[PERL_MULTICONCAT_IX_PLAIN_PV/LEN] == (NULL,0) and there is
639 * one set of segment lengths.
641 * * If the string has different plain and utf8 representations
642 * (e.g. "\x80"), then then aux[PERL_MULTICONCAT_IX_PLAIN_PV/LEN]]
643 * holds the plain rep, while aux[PERL_MULTICONCAT_IX_UTF8_PV/LEN]
644 * holds the utf8 rep, and there are 2 sets of segment lengths,
645 * with the utf8 set following after the plain set.
647 * On entry to this section the (pv,len) pairs in svpv_buf have the
648 * following meanings:
649 * (pv, len) a plain string
650 * (pv, -len) a utf8 string
651 * (NULL, 0) left-most targ \ linked together R-to-L
652 * (next, 0) other targ / in targ_chain
655 /* turn off utf8 handling if 'use bytes' is in scope */
656 if (UNLIKELY(dst_utf8 && IN_BYTES)) {
659 /* undo all the negative lengths which flag utf8-ness */
660 for (svpv_p = svpv_buf; svpv_p < svpv_end; svpv_p++) {
661 SSize_t len = svpv_p->len;
667 /* grow += total of lengths of constant string segments */
670 len = aux[dst_utf8 ? PERL_MULTICONCAT_IX_UTF8_LEN
671 : PERL_MULTICONCAT_IX_PLAIN_LEN].ssize;
672 slow_concat = cBOOL(len);
676 const_lens = aux + PERL_MULTICONCAT_IX_LENGTHS;
679 const_pv = aux[PERL_MULTICONCAT_IX_UTF8_PV].pv;
680 if ( aux[PERL_MULTICONCAT_IX_PLAIN_PV].pv
681 && const_pv != aux[PERL_MULTICONCAT_IX_PLAIN_PV].pv)
682 /* separate sets of lengths for plain and utf8 */
683 const_lens += nargs + 1;
685 /* If the result is utf8 but some of the args aren't,
686 * calculate how much extra growth is needed for all the chars
687 * which will expand to two utf8 bytes.
688 * Also, if the growth is non-zero, negate the length to indicate
689 * that this this is a variant string. Conversely, un-negate the
690 * length on utf8 args (which was only needed to flag non-utf8
691 * args in this loop */
692 for (svpv_p = svpv_buf; svpv_p < svpv_end; svpv_p++) {
701 extra = variant_under_utf8_count((U8 *) svpv_p->pv,
702 (U8 *) svpv_p->pv + len);
703 if (UNLIKELY(extra)) {
705 /* -ve len indicates special handling */
706 svpv_p->len = -(len + extra);
712 const_pv = aux[PERL_MULTICONCAT_IX_PLAIN_PV].pv;
714 /* unrolled SvGROW(), except don't check for SVf_IsCOW, which should
715 * already have been dropped */
716 assert(!SvIsCOW(targ));
717 targ_pv = (SvLEN(targ) < (grow) ? sv_grow(targ,grow) : SvPVX(targ));
720 /* --------------------------------------------------------------
723 * Now that targ has been grown, we know the final address of the targ
724 * PVX, if needed. Preserve / move targ contents if appending or if
725 * targ appears on RHS.
727 * Also update svpv_buf slots in targ_chain.
729 * Don't bother with any of this if the target length is zero:
730 * targ_len is set to zero unless we're appending or targ appears on
731 * RHS. And even if it is, we can optimise by skipping this chunk of
732 * code for zero targ_len. In the latter case, we don't need to update
733 * the slots in targ_chain with the (zero length) target string, since
734 * we set the len in such slots to 0 earlier, and since the Copy() is
735 * skipped on zero length, it doesn't matter what svpv_p->pv contains.
737 * On entry to this section the (pv,len) pairs in svpv_buf have the
738 * following meanings:
739 * (pv, len) a pure-plain or utf8 string
740 * (pv, -(len+extra)) a plain string which will expand by 'extra'
741 * bytes when converted to utf8
742 * (NULL, 0) left-most targ \ linked together R-to-L
743 * (next, 0) other targ / in targ_chain
745 * On exit, the targ contents will have been moved to the
746 * earliest place they are needed (e.g. $x = "abc$x" will shift them
747 * 3 bytes, while $x .= ... will leave them at the beginning);
748 * and dst_pv will point to the location within SvPVX(targ) where the
749 * next arg should be copied.
752 svpv_base = svpv_buf;
755 struct multiconcat_svpv *tc_stop;
756 char *targ_buf = targ_pv; /* ptr to original targ string */
758 assert(is_append || targ_count);
765 /* The targ appears on RHS, e.g. '$t = $a . $t . $t'.
766 * Move the current contents of targ to the first
767 * position where it's needed, and use that as the src buffer
768 * for any further uses (such as the second RHS $t above).
769 * In calculating the first position, we need to sum the
770 * lengths of all consts and args before that.
773 UNOP_AUX_item *lens = const_lens;
774 /* length of first const string segment */
775 STRLEN offset = lens->ssize > 0 ? lens->ssize : 0;
783 break; /* the first targ argument */
784 /* add lengths of the next arg and const string segment */
786 if (len < 0) /* variant args have this */
788 offset += (STRLEN)len;
789 len = (++lens)->ssize;
790 offset += (len >= 0) ? (STRLEN)len : 0;
792 /* all args and consts so far are empty; update
793 * the start position for the concat later */
798 assert(svpv_p < svpv_end);
803 Move(targ_pv, targ_buf, targ_len, char);
804 /* a negative length implies don't Copy(), but do increment */
805 svpv_p->len = -((SSize_t)targ_len);
809 /* skip the first targ copy */
815 /* Don't populate the first targ slot in the loop below; it's
816 * either not used because we advanced svpv_base beyond it, or
817 * we already stored the special -targ_len value in it
822 /* populate slots in svpv_buf representing targ on RHS */
823 while (targ_chain != tc_stop) {
824 struct multiconcat_svpv *p = targ_chain;
825 targ_chain = (struct multiconcat_svpv *)(p->pv);
827 p->len = (SSize_t)targ_len;
832 /* --------------------------------------------------------------
835 * Append all the args in svpv_buf, plus the const strings, to targ.
837 * On entry to this section the (pv,len) pairs in svpv_buf have the
838 * following meanings:
839 * (pv, len) a pure-plain or utf8 string (which may be targ)
840 * (pv, -(len+extra)) a plain string which will expand by 'extra'
841 * bytes when converted to utf8
842 * (0, -len) left-most targ, whose content has already
843 * been copied. Just advance targ_pv by len.
846 /* If there are no constant strings and no special case args
847 * (svpv_p->len < 0), use a simpler, more efficient concat loop
850 for (svpv_p = svpv_base; svpv_p < svpv_end; svpv_p++) {
851 SSize_t len = svpv_p->len;
854 Copy(svpv_p->pv, targ_pv, len, char);
857 const_lens += (svpv_end - svpv_base + 1);
860 /* Note that we iterate the loop nargs+1 times: to append nargs
861 * arguments and nargs+1 constant strings. For example, "-$a-$b-"
863 svpv_p = svpv_base - 1;
866 SSize_t len = (const_lens++)->ssize;
868 /* append next const string segment */
870 Copy(const_pv, targ_pv, len, char);
875 if (++svpv_p == svpv_end)
878 /* append next arg */
881 if (LIKELY(len > 0)) {
882 Copy(svpv_p->pv, targ_pv, len, char);
885 else if (UNLIKELY(len < 0)) {
886 /* negative length indicates two special cases */
887 const char *p = svpv_p->pv;
890 /* copy plain-but-variant pv to a utf8 targ */
891 char * end_pv = targ_pv + len;
893 while (targ_pv < end_pv) {
895 append_utf8_from_native_byte(c, (U8**)&targ_pv);
899 /* arg is already-copied targ */
907 SvCUR_set(targ, targ_pv - SvPVX(targ));
908 assert(grow >= SvCUR(targ) + 1);
909 assert(SvLEN(targ) >= SvCUR(targ) + 1);
911 /* --------------------------------------------------------------
922 /* --------------------------------------------------------------
925 * We only get here if any of the args (or targ too in the case of
926 * append) have something which might cause side effects, such
927 * as magic, overload, or an undef value in the presence of warnings.
928 * In that case, any earlier attempt to stringify the args will have
929 * been abandoned, and we come here instead.
931 * Here, we concat each arg in turn the old-fashioned way: essentially
932 * emulating pp_concat() in a loop. This means that all the weird edge
933 * cases will be handled correctly, if not necessarily speedily.
935 * Note that some args may already have been stringified - those are
936 * processed again, which is safe, since only args without side-effects
937 * were stringified earlier.
949 const char *cpv = aux[PERL_MULTICONCAT_IX_PLAIN_PV].pv;
950 UNOP_AUX_item *lens = aux + PERL_MULTICONCAT_IX_LENGTHS;
951 Size_t arg_count = 0; /* how many args have been processed */
954 cpv = aux[PERL_MULTICONCAT_IX_UTF8_PV].pv;
958 svp = toparg - nargs + 1;
962 * plus possible nargs+1 consts,
963 * plus, if appending, a final targ in an extra last iteration
967 for (i = 0; i <= n; i++) {
970 /* if necessary, stringify the final RHS result in
971 * something like $targ .= "$a$b$c" - simulating
975 && (PL_op->op_private &OPpMULTICONCAT_STRINGIFY)
977 /* extra conditions for backwards compatibility:
978 * probably incorrect, but keep the existing behaviour
979 * for now. The rules are:
980 * $x = "$ov" single arg: stringify;
981 * $x = "$ov$y" multiple args: don't stringify,
982 * $lex = "$ov$y$z" except TARGMY with at least 2 concats
987 && (PL_op->op_private & OPpTARGET_MY)
988 && !(PL_op->op_private & OPpLVAL_INTRO)
993 SV *tmp = sv_newmortal();
994 sv_copypv(tmp, left);
999 /* do one extra iteration to handle $targ in $targ .= ... */
1000 if (i == n && !is_append)
1003 /* get the next arg SV or regen the next const SV */
1004 len = lens[i >> 1].ssize;
1006 /* handle the final targ .= (....) */
1011 right = svp[(i >> 1)];
1013 continue; /* no const in this position */
1015 right = newSVpvn_flags(cpv, len, (utf8 | SVs_TEMP));
1021 if (arg_count <= 1) {
1023 continue; /* need at least two SVs to concat together */
1026 if (arg_count == 2 && i < n) {
1027 /* for the first concat, create a mortal acting like the
1028 * padtmp from OP_CONST. In later iterations this will
1030 nexttarg = sv_newmortal();
1038 /* Handle possible overloading.
1039 * This is basically an unrolled
1040 * tryAMAGICbin_MG(concat_amg, AMGf_assign);
1042 * Perl_try_amagic_bin()
1043 * call, but using left and right rather than SP[-1], SP[0],
1044 * and not relying on OPf_STACKED implying .=
1047 if ((SvFLAGS(left)|SvFLAGS(right)) & (SVf_ROK|SVs_GMG)) {
1052 if ((SvAMAGIC(left) || SvAMAGIC(right))
1053 /* sprintf doesn't do concat overloading,
1054 * but allow for $x .= sprintf(...)
1056 && ( !(PL_op->op_private & OPpMULTICONCAT_FAKE)
1060 SV * const tmpsv = amagic_call(left, right, concat_amg,
1061 (nextappend ? AMGf_assign: 0));
1063 /* NB: tryAMAGICbin_MG() includes an SvPADMY test
1064 * here, which isn;t needed as any implicit
1065 * assign does under OPpTARGET_MY is done after
1068 sv_setsv(left, tmpsv);
1077 /* if both args are the same magical value, make one a copy */
1078 if (left == right && SvGMAGICAL(left)) {
1079 left = sv_newmortal();
1080 /* Print the uninitialized warning now, so it includes the
1083 if (ckWARN(WARN_UNINITIALIZED))
1084 report_uninit(right);
1085 sv_setsv_flags(left, &PL_sv_no, 0);
1088 sv_setsv_flags(left, right, 0);
1093 /* nexttarg = left . right */
1094 S_do_concat(aTHX_ left, right, nexttarg, 0);
1098 SP = toparg - stack_adj + 1;
1100 /* Assign result of all RHS concats (left) to LHS (targ).
1101 * If we are appending, targ will already have been appended to in
1106 sv_setsv(targ, left);
1115 /* push the elements of av onto the stack.
1116 * Returns PL_op->op_next to allow tail-call optimisation of its callers */
1119 S_pushav(pTHX_ AV* const av)
1122 const SSize_t maxarg = AvFILL(av) + 1;
1124 if (UNLIKELY(SvRMAGICAL(av))) {
1126 for (i=0; i < (PADOFFSET)maxarg; i++) {
1127 SV ** const svp = av_fetch(av, i, FALSE);
1128 SP[i+1] = LIKELY(svp)
1130 : UNLIKELY(PL_op->op_flags & OPf_MOD)
1137 for (i=0; i < (PADOFFSET)maxarg; i++) {
1138 SV *sv = AvARRAY(av)[i];
1139 SP[i+1] = LIKELY(sv)
1141 : UNLIKELY(PL_op->op_flags & OPf_MOD)
1152 /* ($lex1,@lex2,...) or my ($lex1,@lex2,...) */
1157 PADOFFSET base = PL_op->op_targ;
1158 int count = (int)(PL_op->op_private) & OPpPADRANGE_COUNTMASK;
1159 if (PL_op->op_flags & OPf_SPECIAL) {
1160 /* fake the RHS of my ($x,$y,..) = @_ */
1162 (void)S_pushav(aTHX_ GvAVn(PL_defgv));
1166 /* note, this is only skipped for compile-time-known void cxt */
1167 if ((PL_op->op_flags & OPf_WANT) != OPf_WANT_VOID) {
1172 for (i = 0; i <count; i++)
1173 *++SP = PAD_SV(base+i);
1175 if (PL_op->op_private & OPpLVAL_INTRO) {
1176 SV **svp = &(PAD_SVl(base));
1177 const UV payload = (UV)(
1178 (base << (OPpPADRANGE_COUNTSHIFT + SAVE_TIGHT_SHIFT))
1179 | (count << SAVE_TIGHT_SHIFT)
1180 | SAVEt_CLEARPADRANGE);
1183 STATIC_ASSERT_STMT(OPpPADRANGE_COUNTMASK + 1 == (1 << OPpPADRANGE_COUNTSHIFT));
1184 assert((payload >> (OPpPADRANGE_COUNTSHIFT+SAVE_TIGHT_SHIFT))
1192 for (i = 0; i <count; i++)
1193 SvPADSTALE_off(*svp++); /* mark lexical as active */
1204 OP * const op = PL_op;
1205 /* access PL_curpad once */
1206 SV ** const padentry = &(PAD_SVl(op->op_targ));
1211 PUTBACK; /* no pop/push after this, TOPs ok */
1213 if (op->op_flags & OPf_MOD) {
1214 if (op->op_private & OPpLVAL_INTRO)
1215 if (!(op->op_private & OPpPAD_STATE))
1216 save_clearsv(padentry);
1217 if (op->op_private & OPpDEREF) {
1218 /* TOPs is equivalent to TARG here. Using TOPs (SP) rather
1219 than TARG reduces the scope of TARG, so it does not
1220 span the call to save_clearsv, resulting in smaller
1222 TOPs = vivify_ref(TOPs, op->op_private & OPpDEREF);
1232 /* pp_coreargs pushes a NULL to indicate no args passed to
1233 * CORE::readline() */
1236 tryAMAGICunTARGETlist(iter_amg, 0);
1237 PL_last_in_gv = MUTABLE_GV(*PL_stack_sp--);
1239 else PL_last_in_gv = PL_argvgv, PL_stack_sp--;
1240 if (!isGV_with_GP(PL_last_in_gv)) {
1241 if (SvROK(PL_last_in_gv) && isGV_with_GP(SvRV(PL_last_in_gv)))
1242 PL_last_in_gv = MUTABLE_GV(SvRV(PL_last_in_gv));
1245 XPUSHs(MUTABLE_SV(PL_last_in_gv));
1247 Perl_pp_rv2gv(aTHX);
1248 PL_last_in_gv = MUTABLE_GV(*PL_stack_sp--);
1249 assert((SV*)PL_last_in_gv == &PL_sv_undef || isGV_with_GP(PL_last_in_gv));
1252 return do_readline();
1260 tryAMAGICbin_MG(eq_amg, AMGf_set|AMGf_numeric);
1264 (SvIOK_notUV(left) && SvIOK_notUV(right))
1265 ? (SvIVX(left) == SvIVX(right))
1266 : ( do_ncmp(left, right) == 0)
1272 /* also used for: pp_i_preinc() */
1276 SV *sv = *PL_stack_sp;
1278 if (LIKELY(((sv->sv_flags &
1279 (SVf_THINKFIRST|SVs_GMG|SVf_IVisUV|
1280 SVf_IOK|SVf_NOK|SVf_POK|SVp_NOK|SVp_POK|SVf_ROK))
1282 && SvIVX(sv) != IV_MAX)
1284 SvIV_set(sv, SvIVX(sv) + 1);
1286 else /* Do all the PERL_PRESERVE_IVUV and hard cases in sv_inc */
1293 /* also used for: pp_i_predec() */
1297 SV *sv = *PL_stack_sp;
1299 if (LIKELY(((sv->sv_flags &
1300 (SVf_THINKFIRST|SVs_GMG|SVf_IVisUV|
1301 SVf_IOK|SVf_NOK|SVf_POK|SVp_NOK|SVp_POK|SVf_ROK))
1303 && SvIVX(sv) != IV_MIN)
1305 SvIV_set(sv, SvIVX(sv) - 1);
1307 else /* Do all the PERL_PRESERVE_IVUV and hard cases in sv_dec */
1314 /* also used for: pp_orassign() */
1325 if (PL_op->op_type == OP_OR)
1327 RETURNOP(cLOGOP->op_other);
1332 /* also used for: pp_dor() pp_dorassign() */
1339 const int op_type = PL_op->op_type;
1340 const bool is_dor = (op_type == OP_DOR || op_type == OP_DORASSIGN);
1345 if (UNLIKELY(!sv || !SvANY(sv))) {
1346 if (op_type == OP_DOR)
1348 RETURNOP(cLOGOP->op_other);
1354 if (UNLIKELY(!sv || !SvANY(sv)))
1359 switch (SvTYPE(sv)) {
1361 if (AvMAX(sv) >= 0 || SvGMAGICAL(sv) || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
1365 if (HvARRAY(sv) || SvGMAGICAL(sv) || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
1369 if (CvROOT(sv) || CvXSUB(sv))
1382 if(op_type == OP_DOR)
1384 RETURNOP(cLOGOP->op_other);
1386 /* assuming OP_DEFINED */
1396 dSP; dATARGET; bool useleft; SV *svl, *svr;
1398 tryAMAGICbin_MG(add_amg, AMGf_assign|AMGf_numeric);
1402 #ifdef PERL_PRESERVE_IVUV
1404 /* special-case some simple common cases */
1405 if (!((svl->sv_flags|svr->sv_flags) & (SVf_IVisUV|SVs_GMG))) {
1407 U32 flags = (svl->sv_flags & svr->sv_flags);
1408 if (flags & SVf_IOK) {
1409 /* both args are simple IVs */
1414 topl = ((UV)il) >> (UVSIZE * 8 - 2);
1415 topr = ((UV)ir) >> (UVSIZE * 8 - 2);
1417 /* if both are in a range that can't under/overflow, do a
1418 * simple integer add: if the top of both numbers
1419 * are 00 or 11, then it's safe */
1420 if (!( ((topl+1) | (topr+1)) & 2)) {
1422 TARGi(il + ir, 0); /* args not GMG, so can't be tainted */
1428 else if (flags & SVf_NOK) {
1429 /* both args are NVs */
1434 #if defined(NAN_COMPARE_BROKEN) && defined(Perl_isnan)
1435 !Perl_isnan(nl) && nl == (NV)(il = (IV)nl)
1436 && !Perl_isnan(nr) && nr == (NV)(ir = (IV)nr)
1438 nl == (NV)(il = (IV)nl) && nr == (NV)(ir = (IV)nr)
1441 /* nothing was lost by converting to IVs */
1444 TARGn(nl + nr, 0); /* args not GMG, so can't be tainted */
1452 useleft = USE_LEFT(svl);
1453 /* We must see if we can perform the addition with integers if possible,
1454 as the integer code detects overflow while the NV code doesn't.
1455 If either argument hasn't had a numeric conversion yet attempt to get
1456 the IV. It's important to do this now, rather than just assuming that
1457 it's not IOK as a PV of "9223372036854775806" may not take well to NV
1458 addition, and an SV which is NOK, NV=6.0 ought to be coerced to
1459 integer in case the second argument is IV=9223372036854775806
1460 We can (now) rely on sv_2iv to do the right thing, only setting the
1461 public IOK flag if the value in the NV (or PV) slot is truly integer.
1463 A side effect is that this also aggressively prefers integer maths over
1464 fp maths for integer values.
1466 How to detect overflow?
1468 C 99 section 6.2.6.1 says
1470 The range of nonnegative values of a signed integer type is a subrange
1471 of the corresponding unsigned integer type, and the representation of
1472 the same value in each type is the same. A computation involving
1473 unsigned operands can never overflow, because a result that cannot be
1474 represented by the resulting unsigned integer type is reduced modulo
1475 the number that is one greater than the largest value that can be
1476 represented by the resulting type.
1480 which I read as "unsigned ints wrap."
1482 signed integer overflow seems to be classed as "exception condition"
1484 If an exceptional condition occurs during the evaluation of an
1485 expression (that is, if the result is not mathematically defined or not
1486 in the range of representable values for its type), the behavior is
1489 (6.5, the 5th paragraph)
1491 I had assumed that on 2s complement machines signed arithmetic would
1492 wrap, hence coded pp_add and pp_subtract on the assumption that
1493 everything perl builds on would be happy. After much wailing and
1494 gnashing of teeth it would seem that irix64 knows its ANSI spec well,
1495 knows that it doesn't need to, and doesn't. Bah. Anyway, the all-
1496 unsigned code below is actually shorter than the old code. :-)
1499 if (SvIV_please_nomg(svr)) {
1500 /* Unless the left argument is integer in range we are going to have to
1501 use NV maths. Hence only attempt to coerce the right argument if
1502 we know the left is integer. */
1509 a_valid = auvok = 1;
1510 /* left operand is undef, treat as zero. + 0 is identity,
1511 Could SETi or SETu right now, but space optimise by not adding
1512 lots of code to speed up what is probably a rarish case. */
1514 /* Left operand is defined, so is it IV? */
1515 if (SvIV_please_nomg(svl)) {
1516 if ((auvok = SvUOK(svl)))
1519 const IV aiv = SvIVX(svl);
1522 auvok = 1; /* Now acting as a sign flag. */
1524 auv = (aiv == IV_MIN) ? (UV)aiv : (UV)(-aiv);
1531 bool result_good = 0;
1534 bool buvok = SvUOK(svr);
1539 const IV biv = SvIVX(svr);
1544 buv = (biv == IV_MIN) ? (UV)biv : (UV)(-biv);
1546 /* ?uvok if value is >= 0. basically, flagged as UV if it's +ve,
1547 else "IV" now, independent of how it came in.
1548 if a, b represents positive, A, B negative, a maps to -A etc
1553 all UV maths. negate result if A negative.
1554 add if signs same, subtract if signs differ. */
1556 if (auvok ^ buvok) {
1560 /* Must get smaller */
1565 if (result <= buv) {
1566 /* result really should be -(auv-buv). as its negation
1567 of true value, need to swap our result flag */
1584 if (result <= (UV)IV_MIN)
1585 SETi(result == (UV)IV_MIN
1586 ? IV_MIN : -(IV)result);
1588 /* result valid, but out of range for IV. */
1589 SETn( -(NV)result );
1593 } /* Overflow, drop through to NVs. */
1598 useleft = USE_LEFT(svl);
1602 NV value = SvNV_nomg(svr);
1605 /* left operand is undef, treat as zero. + 0.0 is identity. */
1609 SETn( value + SvNV_nomg(svl) );
1615 /* also used for: pp_aelemfast_lex() */
1620 AV * const av = PL_op->op_type == OP_AELEMFAST_LEX
1621 ? MUTABLE_AV(PAD_SV(PL_op->op_targ)) : GvAVn(cGVOP_gv);
1622 const U32 lval = PL_op->op_flags & OPf_MOD;
1623 const I8 key = (I8)PL_op->op_private;
1627 assert(SvTYPE(av) == SVt_PVAV);
1631 /* inlined av_fetch() for simple cases ... */
1632 if (!SvRMAGICAL(av) && key >= 0 && key <= AvFILLp(av)) {
1633 sv = AvARRAY(av)[key];
1640 /* ... else do it the hard way */
1641 svp = av_fetch(av, key, lval);
1642 sv = (svp ? *svp : &PL_sv_undef);
1644 if (UNLIKELY(!svp && lval))
1645 DIE(aTHX_ PL_no_aelem, (int)key);
1647 if (!lval && SvRMAGICAL(av) && SvGMAGICAL(sv)) /* see note in pp_helem() */
1655 dSP; dMARK; dTARGET;
1657 do_join(TARG, *MARK, MARK, SP);
1663 /* Oversized hot code. */
1665 /* also used for: pp_say() */
1669 dSP; dMARK; dORIGMARK;
1673 = (PL_op->op_flags & OPf_STACKED) ? MUTABLE_GV(*++MARK) : PL_defoutgv;
1677 && (mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar)))
1680 if (MARK == ORIGMARK) {
1681 /* If using default handle then we need to make space to
1682 * pass object as 1st arg, so move other args up ...
1686 Move(MARK, MARK + 1, (SP - MARK) + 1, SV*);
1689 return Perl_tied_method(aTHX_ SV_CONST(PRINT), mark - 1, MUTABLE_SV(io),
1691 (G_SCALAR | TIED_METHOD_ARGUMENTS_ON_STACK
1692 | (PL_op->op_type == OP_SAY
1693 ? TIED_METHOD_SAY : 0)), sp - mark);
1696 if ( gv && GvEGVx(gv) && (io = GvIO(GvEGV(gv)))
1697 && (mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar)))
1700 SETERRNO(EBADF,RMS_IFI);
1703 else if (!(fp = IoOFP(io))) {
1705 report_wrongway_fh(gv, '<');
1708 SETERRNO(EBADF,IoIFP(io)?RMS_FAC:RMS_IFI);
1712 SV * const ofs = GvSV(PL_ofsgv); /* $, */
1714 if (ofs && (SvGMAGICAL(ofs) || SvOK(ofs))) {
1715 while (MARK <= SP) {
1716 if (!do_print(*MARK, fp))
1720 /* don't use 'ofs' here - it may be invalidated by magic callbacks */
1721 if (!do_print(GvSV(PL_ofsgv), fp)) {
1729 while (MARK <= SP) {
1730 if (!do_print(*MARK, fp))
1738 if (PL_op->op_type == OP_SAY) {
1739 if (PerlIO_write(fp, "\n", 1) == 0 || PerlIO_error(fp))
1742 else if (PL_ors_sv && SvOK(PL_ors_sv))
1743 if (!do_print(PL_ors_sv, fp)) /* $\ */
1746 if (IoFLAGS(io) & IOf_FLUSH)
1747 if (PerlIO_flush(fp) == EOF)
1757 XPUSHs(&PL_sv_undef);
1762 /* do the common parts of pp_padhv() and pp_rv2hv()
1763 * It assumes the caller has done EXTEND(SP, 1) or equivalent.
1764 * 'is_keys' indicates the OPpPADHV_ISKEYS/OPpRV2HV_ISKEYS flag is set.
1765 * 'has_targ' indicates that the op has a target - this should
1766 * be a compile-time constant so that the code can constant-folded as
1770 PERL_STATIC_INLINE OP*
1771 S_padhv_rv2hv_common(pTHX_ HV *hv, U8 gimme, bool is_keys, bool has_targ)
1780 assert(PL_op->op_type == OP_PADHV || PL_op->op_type == OP_RV2HV);
1782 if (gimme == G_ARRAY) {
1788 /* 'keys %h' masquerading as '%h': reset iterator */
1789 (void)hv_iterinit(hv);
1791 if (gimme == G_VOID)
1794 is_bool = ( PL_op->op_private & OPpTRUEBOOL
1795 || ( PL_op->op_private & OPpMAYBE_TRUEBOOL
1796 && block_gimme() == G_VOID));
1797 is_tied = SvRMAGICAL(hv) && (mg = mg_find(MUTABLE_SV(hv), PERL_MAGIC_tied));
1799 if (UNLIKELY(is_tied)) {
1800 if (is_keys && !is_bool) {
1802 while (hv_iternext(hv))
1807 sv = magic_scalarpack(hv, mg);
1814 sv = i ? &PL_sv_yes : &PL_sv_zero;
1825 #ifdef PERL_OP_PARENT
1827 /* parent op should be an unused OP_KEYS whose targ we can
1832 assert(!OpHAS_SIBLING(PL_op));
1833 k = PL_op->op_sibparent;
1834 assert(k->op_type == OP_KEYS);
1835 TARG = PAD_SV(k->op_targ);
1849 /* This is also called directly by pp_lvavref. */
1854 assert(SvTYPE(TARG) == SVt_PVAV);
1855 if (UNLIKELY( PL_op->op_private & OPpLVAL_INTRO ))
1856 if (LIKELY( !(PL_op->op_private & OPpPAD_STATE) ))
1857 SAVECLEARSV(PAD_SVl(PL_op->op_targ));
1860 if (PL_op->op_flags & OPf_REF) {
1864 else if (PL_op->op_private & OPpMAYBE_LVSUB) {
1865 const I32 flags = is_lvalue_sub();
1866 if (flags && !(flags & OPpENTERSUB_INARGS)) {
1867 if (GIMME_V == G_SCALAR)
1868 /* diag_listed_as: Can't return %s to lvalue scalar context */
1869 Perl_croak(aTHX_ "Can't return array to lvalue scalar context");
1876 if (gimme == G_ARRAY)
1877 return S_pushav(aTHX_ (AV*)TARG);
1879 if (gimme == G_SCALAR) {
1880 const SSize_t maxarg = AvFILL(MUTABLE_AV(TARG)) + 1;
1883 else if (PL_op->op_private & OPpTRUEBOOL)
1897 assert(SvTYPE(TARG) == SVt_PVHV);
1898 if (UNLIKELY( PL_op->op_private & OPpLVAL_INTRO ))
1899 if (LIKELY( !(PL_op->op_private & OPpPAD_STATE) ))
1900 SAVECLEARSV(PAD_SVl(PL_op->op_targ));
1904 if (PL_op->op_flags & OPf_REF) {
1908 else if (PL_op->op_private & OPpMAYBE_LVSUB) {
1909 const I32 flags = is_lvalue_sub();
1910 if (flags && !(flags & OPpENTERSUB_INARGS)) {
1911 if (GIMME_V == G_SCALAR)
1912 /* diag_listed_as: Can't return %s to lvalue scalar context */
1913 Perl_croak(aTHX_ "Can't return hash to lvalue scalar context");
1921 return S_padhv_rv2hv_common(aTHX_ (HV*)TARG, gimme,
1922 cBOOL(PL_op->op_private & OPpPADHV_ISKEYS),
1927 /* also used for: pp_rv2hv() */
1928 /* also called directly by pp_lvavref */
1933 const U8 gimme = GIMME_V;
1934 static const char an_array[] = "an ARRAY";
1935 static const char a_hash[] = "a HASH";
1936 const bool is_pp_rv2av = PL_op->op_type == OP_RV2AV
1937 || PL_op->op_type == OP_LVAVREF;
1938 const svtype type = is_pp_rv2av ? SVt_PVAV : SVt_PVHV;
1942 if (UNLIKELY(SvAMAGIC(sv))) {
1943 sv = amagic_deref_call(sv, is_pp_rv2av ? to_av_amg : to_hv_amg);
1946 if (UNLIKELY(SvTYPE(sv) != type))
1947 /* diag_listed_as: Not an ARRAY reference */
1948 DIE(aTHX_ "Not %s reference", is_pp_rv2av ? an_array : a_hash);
1949 else if (UNLIKELY(PL_op->op_flags & OPf_MOD
1950 && PL_op->op_private & OPpLVAL_INTRO))
1951 Perl_croak(aTHX_ "%s", PL_no_localize_ref);
1953 else if (UNLIKELY(SvTYPE(sv) != type)) {
1956 if (!isGV_with_GP(sv)) {
1957 gv = Perl_softref2xv(aTHX_ sv, is_pp_rv2av ? an_array : a_hash,
1963 gv = MUTABLE_GV(sv);
1965 sv = is_pp_rv2av ? MUTABLE_SV(GvAVn(gv)) : MUTABLE_SV(GvHVn(gv));
1966 if (PL_op->op_private & OPpLVAL_INTRO)
1967 sv = is_pp_rv2av ? MUTABLE_SV(save_ary(gv)) : MUTABLE_SV(save_hash(gv));
1969 if (PL_op->op_flags & OPf_REF) {
1973 else if (UNLIKELY(PL_op->op_private & OPpMAYBE_LVSUB)) {
1974 const I32 flags = is_lvalue_sub();
1975 if (flags && !(flags & OPpENTERSUB_INARGS)) {
1976 if (gimme != G_ARRAY)
1977 goto croak_cant_return;
1984 AV *const av = MUTABLE_AV(sv);
1986 if (gimme == G_ARRAY) {
1989 return S_pushav(aTHX_ av);
1992 if (gimme == G_SCALAR) {
1993 const SSize_t maxarg = AvFILL(av) + 1;
1994 if (PL_op->op_private & OPpTRUEBOOL)
1995 SETs(maxarg ? &PL_sv_yes : &PL_sv_zero);
2004 return S_padhv_rv2hv_common(aTHX_ (HV*)sv, gimme,
2005 cBOOL(PL_op->op_private & OPpRV2HV_ISKEYS),
2011 Perl_croak(aTHX_ "Can't return %s to lvalue scalar context",
2012 is_pp_rv2av ? "array" : "hash");
2017 S_do_oddball(pTHX_ SV **oddkey, SV **firstkey)
2019 PERL_ARGS_ASSERT_DO_ODDBALL;
2022 if (ckWARN(WARN_MISC)) {
2024 if (oddkey == firstkey &&
2026 (SvTYPE(SvRV(*oddkey)) == SVt_PVAV ||
2027 SvTYPE(SvRV(*oddkey)) == SVt_PVHV))
2029 err = "Reference found where even-sized list expected";
2032 err = "Odd number of elements in hash assignment";
2033 Perl_warner(aTHX_ packWARN(WARN_MISC), "%s", err);
2040 /* Do a mark and sweep with the SVf_BREAK flag to detect elements which
2041 * are common to both the LHS and RHS of an aassign, and replace them
2042 * with copies. All these copies are made before the actual list assign is
2045 * For example in ($a,$b) = ($b,$a), assigning the value of the first RHS
2046 * element ($b) to the first LH element ($a), modifies $a; when the
2047 * second assignment is done, the second RH element now has the wrong
2048 * value. So we initially replace the RHS with ($b, mortalcopy($a)).
2049 * Note that we don't need to make a mortal copy of $b.
2051 * The algorithm below works by, for every RHS element, mark the
2052 * corresponding LHS target element with SVf_BREAK. Then if the RHS
2053 * element is found with SVf_BREAK set, it means it would have been
2054 * modified, so make a copy.
2055 * Note that by scanning both LHS and RHS in lockstep, we avoid
2056 * unnecessary copies (like $b above) compared with a naive
2057 * "mark all LHS; copy all marked RHS; unmark all LHS".
2059 * If the LHS element is a 'my' declaration' and has a refcount of 1, then
2060 * it can't be common and can be skipped.
2062 * On DEBUGGING builds it takes an extra boolean, fake. If true, it means
2063 * that we thought we didn't need to call S_aassign_copy_common(), but we
2064 * have anyway for sanity checking. If we find we need to copy, then panic.
2067 PERL_STATIC_INLINE void
2068 S_aassign_copy_common(pTHX_ SV **firstlelem, SV **lastlelem,
2069 SV **firstrelem, SV **lastrelem
2078 SSize_t lcount = lastlelem - firstlelem + 1;
2079 bool marked = FALSE; /* have we marked any LHS with SVf_BREAK ? */
2080 bool const do_rc1 = cBOOL(PL_op->op_private & OPpASSIGN_COMMON_RC1);
2081 bool copy_all = FALSE;
2083 assert(!PL_in_clean_all); /* SVf_BREAK not already in use */
2084 assert(firstlelem < lastlelem); /* at least 2 LH elements */
2085 assert(firstrelem < lastrelem); /* at least 2 RH elements */
2089 /* we never have to copy the first RH element; it can't be corrupted
2090 * by assigning something to the corresponding first LH element.
2091 * So this scan does in a loop: mark LHS[N]; test RHS[N+1]
2093 relem = firstrelem + 1;
2095 for (; relem <= lastrelem; relem++) {
2098 /* mark next LH element */
2100 if (--lcount >= 0) {
2103 if (UNLIKELY(!svl)) {/* skip AV alias marker */
2104 assert (lelem <= lastlelem);
2110 if (SvSMAGICAL(svl)) {
2113 if (SvTYPE(svl) == SVt_PVAV || SvTYPE(svl) == SVt_PVHV) {
2116 /* this LH element will consume all further args;
2117 * no need to mark any further LH elements (if any).
2118 * But we still need to scan any remaining RHS elements;
2119 * set lcount negative to distinguish from lcount == 0,
2120 * so the loop condition continues being true
2123 lelem--; /* no need to unmark this element */
2125 else if (!(do_rc1 && SvREFCNT(svl) == 1) && !SvIMMORTAL(svl)) {
2126 SvFLAGS(svl) |= SVf_BREAK;
2130 /* don't check RH element if no SVf_BREAK flags set yet */
2137 /* see if corresponding RH element needs copying */
2143 if (UNLIKELY(SvFLAGS(svr) & (SVf_BREAK|SVs_GMG) || copy_all)) {
2144 U32 brk = (SvFLAGS(svr) & SVf_BREAK);
2148 /* op_dump(PL_op); */
2150 "panic: aassign skipped needed copy of common RH elem %"
2151 UVuf, (UV)(relem - firstrelem));
2155 TAINT_NOT; /* Each item is independent */
2157 /* Dear TODO test in t/op/sort.t, I love you.
2158 (It's relying on a panic, not a "semi-panic" from newSVsv()
2159 and then an assertion failure below.) */
2160 if (UNLIKELY(SvIS_FREED(svr))) {
2161 Perl_croak(aTHX_ "panic: attempt to copy freed scalar %p",
2164 /* avoid break flag while copying; otherwise COW etc
2166 SvFLAGS(svr) &= ~SVf_BREAK;
2167 /* Not newSVsv(), as it does not allow copy-on-write,
2168 resulting in wasteful copies.
2169 Also, we use SV_NOSTEAL in case the SV is used more than
2170 once, e.g. (...) = (f())[0,0]
2171 Where the same SV appears twice on the RHS without a ref
2172 count bump. (Although I suspect that the SV won't be
2173 stealable here anyway - DAPM).
2175 *relem = sv_mortalcopy_flags(svr,
2176 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
2177 /* ... but restore afterwards in case it's needed again,
2178 * e.g. ($a,$b,$c) = (1,$a,$a)
2180 SvFLAGS(svr) |= brk;
2192 while (lelem > firstlelem) {
2193 SV * const svl = *(--lelem);
2195 SvFLAGS(svl) &= ~SVf_BREAK;
2204 SV **lastlelem = PL_stack_sp;
2205 SV **lastrelem = PL_stack_base + POPMARK;
2206 SV **firstrelem = PL_stack_base + POPMARK + 1;
2207 SV **firstlelem = lastrelem + 1;
2212 /* PL_delaymagic is restored by JUMPENV_POP on dieing, so we
2213 * only need to save locally, not on the save stack */
2214 U16 old_delaymagic = PL_delaymagic;
2219 PL_delaymagic = DM_DELAY; /* catch simultaneous items */
2221 /* If there's a common identifier on both sides we have to take
2222 * special care that assigning the identifier on the left doesn't
2223 * clobber a value on the right that's used later in the list.
2226 /* at least 2 LH and RH elements, or commonality isn't an issue */
2227 if (firstlelem < lastlelem && firstrelem < lastrelem) {
2228 for (relem = firstrelem+1; relem <= lastrelem; relem++) {
2229 if (SvGMAGICAL(*relem))
2232 for (lelem = firstlelem; lelem <= lastlelem; lelem++) {
2233 if (*lelem && SvSMAGICAL(*lelem))
2236 if ( PL_op->op_private & (OPpASSIGN_COMMON_SCALAR|OPpASSIGN_COMMON_RC1) ) {
2237 if (PL_op->op_private & OPpASSIGN_COMMON_RC1) {
2238 /* skip the scan if all scalars have a ref count of 1 */
2239 for (lelem = firstlelem; lelem <= lastlelem; lelem++) {
2241 if (!sv || SvREFCNT(sv) == 1)
2243 if (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVAV)
2250 S_aassign_copy_common(aTHX_
2251 firstlelem, lastlelem, firstrelem, lastrelem
2261 /* on debugging builds, do the scan even if we've concluded we
2262 * don't need to, then panic if we find commonality. Note that the
2263 * scanner assumes at least 2 elements */
2264 if (firstlelem < lastlelem && firstrelem < lastrelem) {
2275 if (relem > lastrelem)
2278 /* first lelem loop while there are still relems */
2279 while (LIKELY(lelem <= lastlelem)) {
2283 TAINT_NOT; /* Each item stands on its own, taintwise. */
2285 assert(relem <= lastrelem);
2286 if (UNLIKELY(!lsv)) {
2289 ASSUME(SvTYPE(lsv) == SVt_PVAV);
2292 switch (SvTYPE(lsv)) {
2297 SSize_t nelems = lastrelem - relem + 1;
2298 AV *ary = MUTABLE_AV(lsv);
2300 /* Assigning to an aggregate is tricky. First there is the
2301 * issue of commonality, e.g. @a = ($a[0]). Since the
2302 * stack isn't refcounted, clearing @a prior to storing
2303 * elements will free $a[0]. Similarly with
2304 * sub FETCH { $status[$_[1]] } @status = @tied[0,1];
2306 * The way to avoid these issues is to make the copy of each
2307 * SV (and we normally store a *copy* in the array) *before*
2308 * clearing the array. But this has a problem in that
2309 * if the code croaks during copying, the not-yet-stored copies
2310 * could leak. One way to avoid this is to make all the copies
2311 * mortal, but that's quite expensive.
2313 * The current solution to these issues is to use a chunk
2314 * of the tmps stack as a temporary refcounted-stack. SVs
2315 * will be put on there during processing to avoid leaks,
2316 * but will be removed again before the end of this block,
2317 * so free_tmps() is never normally called. Also, the
2318 * sv_refcnt of the SVs doesn't have to be manipulated, since
2319 * the ownership of 1 reference count is transferred directly
2320 * from the tmps stack to the AV when the SV is stored.
2322 * We disarm slots in the temps stack by storing PL_sv_undef
2323 * there: it doesn't matter if that SV's refcount is
2324 * repeatedly decremented during a croak. But usually this is
2325 * only an interim measure. By the end of this code block
2326 * we try where possible to not leave any PL_sv_undef's on the
2327 * tmps stack e.g. by shuffling newer entries down.
2329 * There is one case where we don't copy: non-magical
2330 * SvTEMP(sv)'s with a ref count of 1. The only owner of these
2331 * is on the tmps stack, so its safe to directly steal the SV
2332 * rather than copying. This is common in things like function
2333 * returns, map etc, which all return a list of such SVs.
2335 * Note however something like @a = (f())[0,0], where there is
2336 * a danger of the same SV being shared: this avoided because
2337 * when the SV is stored as $a[0], its ref count gets bumped,
2338 * so the RC==1 test fails and the second element is copied
2341 * We also use one slot in the tmps stack to hold an extra
2342 * ref to the array, to ensure it doesn't get prematurely
2343 * freed. Again, this is removed before the end of this block.
2345 * Note that OPpASSIGN_COMMON_AGG is used to flag a possible
2346 * @a = ($a[0]) case, but the current implementation uses the
2347 * same algorithm regardless, so ignores that flag. (It *is*
2348 * used in the hash branch below, however).
2351 /* Reserve slots for ary, plus the elems we're about to copy,
2352 * then protect ary and temporarily void the remaining slots
2353 * with &PL_sv_undef */
2354 EXTEND_MORTAL(nelems + 1);
2355 PL_tmps_stack[++PL_tmps_ix] = SvREFCNT_inc_simple_NN(ary);
2356 tmps_base = PL_tmps_ix + 1;
2357 for (i = 0; i < nelems; i++)
2358 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
2359 PL_tmps_ix += nelems;
2361 /* Make a copy of each RHS elem and save on the tmps_stack
2362 * (or pass through where we can optimise away the copy) */
2364 if (UNLIKELY(alias)) {
2365 U32 lval = (gimme == G_ARRAY)
2366 ? (PL_op->op_flags & OPf_MOD || LVRET) : 0;
2367 for (svp = relem; svp <= lastrelem; svp++) {
2372 DIE(aTHX_ "Assigned value is not a reference");
2373 if (SvTYPE(SvRV(rsv)) > SVt_PVLV)
2374 /* diag_listed_as: Assigned value is not %s reference */
2376 "Assigned value is not a SCALAR reference");
2378 *svp = rsv = sv_mortalcopy(rsv);
2379 /* XXX else check for weak refs? */
2380 rsv = SvREFCNT_inc_NN(SvRV(rsv));
2381 assert(tmps_base <= PL_tmps_max);
2382 PL_tmps_stack[tmps_base++] = rsv;
2386 for (svp = relem; svp <= lastrelem; svp++) {
2389 if (SvTEMP(rsv) && !SvGMAGICAL(rsv) && SvREFCNT(rsv) == 1) {
2390 /* can skip the copy */
2391 SvREFCNT_inc_simple_void_NN(rsv);
2396 /* do get before newSV, in case it dies and leaks */
2399 /* see comment in S_aassign_copy_common about
2401 sv_setsv_flags(nsv, rsv,
2402 (SV_DO_COW_SVSETSV|SV_NOSTEAL));
2406 assert(tmps_base <= PL_tmps_max);
2407 PL_tmps_stack[tmps_base++] = rsv;
2411 if (SvRMAGICAL(ary) || AvFILLp(ary) >= 0) /* may be non-empty */
2414 /* store in the array, the SVs that are in the tmps stack */
2416 tmps_base -= nelems;
2418 if (SvMAGICAL(ary) || SvREADONLY(ary) || !AvREAL(ary)) {
2419 /* for arrays we can't cheat with, use the official API */
2420 av_extend(ary, nelems - 1);
2421 for (i = 0; i < nelems; i++) {
2422 SV **svp = &(PL_tmps_stack[tmps_base + i]);
2424 /* A tied store won't take ownership of rsv, so keep
2425 * the 1 refcnt on the tmps stack; otherwise disarm
2426 * the tmps stack entry */
2427 if (av_store(ary, i, rsv))
2428 *svp = &PL_sv_undef;
2429 /* av_store() may have added set magic to rsv */;
2432 /* disarm ary refcount: see comments below about leak */
2433 PL_tmps_stack[tmps_base - 1] = &PL_sv_undef;
2436 /* directly access/set the guts of the AV */
2437 SSize_t fill = nelems - 1;
2438 if (fill > AvMAX(ary))
2439 av_extend_guts(ary, fill, &AvMAX(ary), &AvALLOC(ary),
2441 AvFILLp(ary) = fill;
2442 Copy(&(PL_tmps_stack[tmps_base]), AvARRAY(ary), nelems, SV*);
2443 /* Quietly remove all the SVs from the tmps stack slots,
2444 * since ary has now taken ownership of the refcnt.
2445 * Also remove ary: which will now leak if we die before
2446 * the SvREFCNT_dec_NN(ary) below */
2447 if (UNLIKELY(PL_tmps_ix >= tmps_base + nelems))
2448 Move(&PL_tmps_stack[tmps_base + nelems],
2449 &PL_tmps_stack[tmps_base - 1],
2450 PL_tmps_ix - (tmps_base + nelems) + 1,
2452 PL_tmps_ix -= (nelems + 1);
2455 if (UNLIKELY(PL_delaymagic & DM_ARRAY_ISA))
2456 /* its assumed @ISA set magic can't die and leak ary */
2457 SvSETMAGIC(MUTABLE_SV(ary));
2458 SvREFCNT_dec_NN(ary);
2460 relem = lastrelem + 1;
2464 case SVt_PVHV: { /* normal hash */
2470 SSize_t nelems = lastrelem - relem + 1;
2471 HV *hash = MUTABLE_HV(lsv);
2473 if (UNLIKELY(nelems & 1)) {
2474 do_oddball(lastrelem, relem);
2475 /* we have firstlelem to reuse, it's not needed any more */
2476 *++lastrelem = &PL_sv_undef;
2480 /* See the SVt_PVAV branch above for a long description of
2481 * how the following all works. The main difference for hashes
2482 * is that we treat keys and values separately (and have
2483 * separate loops for them): as for arrays, values are always
2484 * copied (except for the SvTEMP optimisation), since they
2485 * need to be stored in the hash; while keys are only
2486 * processed where they might get prematurely freed or
2489 /* tmps stack slots:
2490 * * reserve a slot for the hash keepalive;
2491 * * reserve slots for the hash values we're about to copy;
2492 * * preallocate for the keys we'll possibly copy or refcount bump
2494 * then protect hash and temporarily void the remaining
2495 * value slots with &PL_sv_undef */
2496 EXTEND_MORTAL(nelems + 1);
2498 /* convert to number of key/value pairs */
2501 PL_tmps_stack[++PL_tmps_ix] = SvREFCNT_inc_simple_NN(hash);
2502 tmps_base = PL_tmps_ix + 1;
2503 for (i = 0; i < nelems; i++)
2504 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
2505 PL_tmps_ix += nelems;
2507 /* Make a copy of each RHS hash value and save on the tmps_stack
2508 * (or pass through where we can optimise away the copy) */
2510 for (svp = relem + 1; svp <= lastrelem; svp += 2) {
2513 if (SvTEMP(rsv) && !SvGMAGICAL(rsv) && SvREFCNT(rsv) == 1) {
2514 /* can skip the copy */
2515 SvREFCNT_inc_simple_void_NN(rsv);
2520 /* do get before newSV, in case it dies and leaks */
2523 /* see comment in S_aassign_copy_common about
2525 sv_setsv_flags(nsv, rsv,
2526 (SV_DO_COW_SVSETSV|SV_NOSTEAL));
2530 assert(tmps_base <= PL_tmps_max);
2531 PL_tmps_stack[tmps_base++] = rsv;
2533 tmps_base -= nelems;
2536 /* possibly protect keys */
2538 if (UNLIKELY(gimme == G_ARRAY)) {
2540 * @a = ((%h = ($$r, 1)), $r = "x");
2541 * $_++ for %h = (1,2,3,4);
2543 EXTEND_MORTAL(nelems);
2544 for (svp = relem; svp <= lastrelem; svp += 2)
2545 *svp = sv_mortalcopy_flags(*svp,
2546 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
2548 else if (PL_op->op_private & OPpASSIGN_COMMON_AGG) {
2549 /* for possible commonality, e.g.
2551 * avoid premature freeing RHS keys by mortalising
2553 * For a magic element, make a copy so that its magic is
2554 * called *before* the hash is emptied (which may affect
2555 * a tied value for example).
2556 * In theory we should check for magic keys in all
2557 * cases, not just under OPpASSIGN_COMMON_AGG, but in
2558 * practice, !OPpASSIGN_COMMON_AGG implies only
2559 * constants or padtmps on the RHS.
2561 EXTEND_MORTAL(nelems);
2562 for (svp = relem; svp <= lastrelem; svp += 2) {
2564 if (UNLIKELY(SvGMAGICAL(rsv))) {
2566 *svp = sv_mortalcopy_flags(*svp,
2567 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
2568 /* allow other branch to continue pushing
2569 * onto tmps stack without checking each time */
2570 n = (lastrelem - relem) >> 1;
2574 PL_tmps_stack[++PL_tmps_ix] =
2575 SvREFCNT_inc_simple_NN(rsv);
2579 if (SvRMAGICAL(hash) || HvUSEDKEYS(hash))
2582 /* now assign the keys and values to the hash */
2586 if (UNLIKELY(gimme == G_ARRAY)) {
2587 /* @a = (%h = (...)) etc */
2589 SV **topelem = relem;
2591 for (i = 0, svp = relem; svp <= lastrelem; i++, svp++) {
2594 /* remove duplicates from list we return */
2595 if (!hv_exists_ent(hash, key, 0)) {
2596 /* copy key back: possibly to an earlier
2597 * stack location if we encountered dups earlier,
2598 * The values will be updated later
2603 /* A tied store won't take ownership of val, so keep
2604 * the 1 refcnt on the tmps stack; otherwise disarm
2605 * the tmps stack entry */
2606 if (hv_store_ent(hash, key, val, 0))
2607 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
2610 /* hv_store_ent() may have added set magic to val */;
2613 if (topelem < svp) {
2614 /* at this point we have removed the duplicate key/value
2615 * pairs from the stack, but the remaining values may be
2616 * wrong; i.e. with (a 1 a 2 b 3) on the stack we've removed
2617 * the (a 2), but the stack now probably contains
2618 * (a <freed> b 3), because { hv_save(a,1); hv_save(a,2) }
2619 * obliterates the earlier key. So refresh all values. */
2620 lastrelem = topelem - 1;
2621 while (relem < lastrelem) {
2623 he = hv_fetch_ent(hash, *relem++, 0, 0);
2624 *relem++ = (he ? HeVAL(he) : &PL_sv_undef);
2630 for (i = 0, svp = relem; svp <= lastrelem; i++, svp++) {
2633 if (hv_store_ent(hash, key, val, 0))
2634 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
2637 /* hv_store_ent() may have added set magic to val */;
2643 /* there are still some 'live' recounts on the tmps stack
2644 * - usually caused by storing into a tied hash. So let
2645 * free_tmps() do the proper but slow job later.
2646 * Just disarm hash refcount: see comments below about leak
2648 PL_tmps_stack[tmps_base - 1] = &PL_sv_undef;
2651 /* Quietly remove all the SVs from the tmps stack slots,
2652 * since hash has now taken ownership of the refcnt.
2653 * Also remove hash: which will now leak if we die before
2654 * the SvREFCNT_dec_NN(hash) below */
2655 if (UNLIKELY(PL_tmps_ix >= tmps_base + nelems))
2656 Move(&PL_tmps_stack[tmps_base + nelems],
2657 &PL_tmps_stack[tmps_base - 1],
2658 PL_tmps_ix - (tmps_base + nelems) + 1,
2660 PL_tmps_ix -= (nelems + 1);
2663 SvREFCNT_dec_NN(hash);
2665 relem = lastrelem + 1;
2670 if (!SvIMMORTAL(lsv)) {
2674 SvTEMP(lsv) && !SvSMAGICAL(lsv) && SvREFCNT(lsv) == 1 &&
2675 (!isGV_with_GP(lsv) || SvFAKE(lsv)) && ckWARN(WARN_MISC)
2678 packWARN(WARN_MISC),
2679 "Useless assignment to a temporary"
2682 /* avoid freeing $$lsv if it might be needed for further
2683 * elements, e.g. ($ref, $foo) = (1, $$ref) */
2685 && ( ((ref = SvRV(lsv)), SvREFCNT(ref)) == 1)
2686 && lelem <= lastlelem
2689 SvREFCNT_inc_simple_void_NN(ref);
2690 /* an unrolled sv_2mortal */
2692 if (UNLIKELY(ix >= PL_tmps_max))
2693 /* speculatively grow enough to cover other
2695 (void)tmps_grow_p(ix + (lastlelem - lelem));
2696 PL_tmps_stack[ix] = ref;
2699 sv_setsv(lsv, *relem);
2703 if (++relem > lastrelem)
2712 /* simplified lelem loop for when there are no relems left */
2713 while (LIKELY(lelem <= lastlelem)) {
2716 TAINT_NOT; /* Each item stands on its own, taintwise. */
2718 if (UNLIKELY(!lsv)) {
2720 ASSUME(SvTYPE(lsv) == SVt_PVAV);
2723 switch (SvTYPE(lsv)) {
2725 if (SvRMAGICAL(lsv) || AvFILLp((SV*)lsv) >= 0) {
2727 if (UNLIKELY(PL_delaymagic & DM_ARRAY_ISA))
2733 if (SvRMAGICAL(lsv) || HvUSEDKEYS((HV*)lsv))
2738 if (!SvIMMORTAL(lsv)) {
2747 TAINT_NOT; /* result of list assign isn't tainted */
2749 if (UNLIKELY(PL_delaymagic & ~DM_DELAY)) {
2750 /* Will be used to set PL_tainting below */
2751 Uid_t tmp_uid = PerlProc_getuid();
2752 Uid_t tmp_euid = PerlProc_geteuid();
2753 Gid_t tmp_gid = PerlProc_getgid();
2754 Gid_t tmp_egid = PerlProc_getegid();
2756 /* XXX $> et al currently silently ignore failures */
2757 if (PL_delaymagic & DM_UID) {
2758 #ifdef HAS_SETRESUID
2760 setresuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
2761 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1,
2763 #elif defined(HAS_SETREUID)
2765 setreuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
2766 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1));
2769 if ((PL_delaymagic & DM_UID) == DM_RUID) {
2770 PERL_UNUSED_RESULT(setruid(PL_delaymagic_uid));
2771 PL_delaymagic &= ~DM_RUID;
2773 # endif /* HAS_SETRUID */
2775 if ((PL_delaymagic & DM_UID) == DM_EUID) {
2776 PERL_UNUSED_RESULT(seteuid(PL_delaymagic_euid));
2777 PL_delaymagic &= ~DM_EUID;
2779 # endif /* HAS_SETEUID */
2780 if (PL_delaymagic & DM_UID) {
2781 if (PL_delaymagic_uid != PL_delaymagic_euid)
2782 DIE(aTHX_ "No setreuid available");
2783 PERL_UNUSED_RESULT(PerlProc_setuid(PL_delaymagic_uid));
2785 #endif /* HAS_SETRESUID */
2787 tmp_uid = PerlProc_getuid();
2788 tmp_euid = PerlProc_geteuid();
2790 /* XXX $> et al currently silently ignore failures */
2791 if (PL_delaymagic & DM_GID) {
2792 #ifdef HAS_SETRESGID
2794 setresgid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
2795 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1,
2797 #elif defined(HAS_SETREGID)
2799 setregid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
2800 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1));
2803 if ((PL_delaymagic & DM_GID) == DM_RGID) {
2804 PERL_UNUSED_RESULT(setrgid(PL_delaymagic_gid));
2805 PL_delaymagic &= ~DM_RGID;
2807 # endif /* HAS_SETRGID */
2809 if ((PL_delaymagic & DM_GID) == DM_EGID) {
2810 PERL_UNUSED_RESULT(setegid(PL_delaymagic_egid));
2811 PL_delaymagic &= ~DM_EGID;
2813 # endif /* HAS_SETEGID */
2814 if (PL_delaymagic & DM_GID) {
2815 if (PL_delaymagic_gid != PL_delaymagic_egid)
2816 DIE(aTHX_ "No setregid available");
2817 PERL_UNUSED_RESULT(PerlProc_setgid(PL_delaymagic_gid));
2819 #endif /* HAS_SETRESGID */
2821 tmp_gid = PerlProc_getgid();
2822 tmp_egid = PerlProc_getegid();
2824 TAINTING_set( TAINTING_get | (tmp_uid && (tmp_euid != tmp_uid || tmp_egid != tmp_gid)) );
2825 #ifdef NO_TAINT_SUPPORT
2826 PERL_UNUSED_VAR(tmp_uid);
2827 PERL_UNUSED_VAR(tmp_euid);
2828 PERL_UNUSED_VAR(tmp_gid);
2829 PERL_UNUSED_VAR(tmp_egid);
2832 PL_delaymagic = old_delaymagic;
2834 if (gimme == G_VOID)
2835 SP = firstrelem - 1;
2836 else if (gimme == G_SCALAR) {
2839 if (PL_op->op_private & OPpASSIGN_TRUEBOOL)
2840 SETs((firstlelem - firstrelem) ? &PL_sv_yes : &PL_sv_zero);
2843 SETi(firstlelem - firstrelem);
2855 PMOP * const pm = cPMOP;
2856 REGEXP * rx = PM_GETRE(pm);
2857 regexp *prog = ReANY(rx);
2858 SV * const pkg = RXp_ENGINE(prog)->qr_package(aTHX_ (rx));
2859 SV * const rv = sv_newmortal();
2863 SvUPGRADE(rv, SVt_IV);
2864 /* For a subroutine describing itself as "This is a hacky workaround" I'm
2865 loathe to use it here, but it seems to be the right fix. Or close.
2866 The key part appears to be that it's essential for pp_qr to return a new
2867 object (SV), which implies that there needs to be an effective way to
2868 generate a new SV from the existing SV that is pre-compiled in the
2870 SvRV_set(rv, MUTABLE_SV(reg_temp_copy(NULL, rx)));
2873 cvp = &( ReANY((REGEXP *)SvRV(rv))->qr_anoncv);
2874 if (UNLIKELY((cv = *cvp) && CvCLONE(*cvp))) {
2875 *cvp = cv_clone(cv);
2876 SvREFCNT_dec_NN(cv);
2880 HV *const stash = gv_stashsv(pkg, GV_ADD);
2881 SvREFCNT_dec_NN(pkg);
2882 (void)sv_bless(rv, stash);
2885 if (UNLIKELY(RXp_ISTAINTED(prog))) {
2887 SvTAINTED_on(SvRV(rv));
2900 SSize_t curpos = 0; /* initial pos() or current $+[0] */
2903 const char *truebase; /* Start of string */
2904 REGEXP *rx = PM_GETRE(pm);
2905 regexp *prog = ReANY(rx);
2907 const U8 gimme = GIMME_V;
2909 const I32 oldsave = PL_savestack_ix;
2910 I32 had_zerolen = 0;
2913 if (PL_op->op_flags & OPf_STACKED)
2924 PUTBACK; /* EVAL blocks need stack_sp. */
2925 /* Skip get-magic if this is a qr// clone, because regcomp has
2927 truebase = prog->mother_re
2928 ? SvPV_nomg_const(TARG, len)
2929 : SvPV_const(TARG, len);
2931 DIE(aTHX_ "panic: pp_match");
2932 strend = truebase + len;
2933 rxtainted = (RXp_ISTAINTED(prog) ||
2934 (TAINT_get && (pm->op_pmflags & PMf_RETAINT)));
2937 /* We need to know this in case we fail out early - pos() must be reset */
2938 global = dynpm->op_pmflags & PMf_GLOBAL;
2940 /* PMdf_USED is set after a ?? matches once */
2943 SvREADONLY(PL_regex_pad[pm->op_pmoffset])
2945 pm->op_pmflags & PMf_USED
2948 DEBUG_r(PerlIO_printf(Perl_debug_log, "?? already matched once"));
2952 /* handle the empty pattern */
2953 if (!RX_PRELEN(rx) && PL_curpm && !prog->mother_re) {
2954 if (PL_curpm == PL_reg_curpm) {
2955 if (PL_curpm_under) {
2956 if (PL_curpm_under == PL_reg_curpm) {
2957 Perl_croak(aTHX_ "Infinite recursion via empty pattern");
2959 pm = PL_curpm_under;
2969 if (RXp_MINLEN(prog) >= 0 && (STRLEN)RXp_MINLEN(prog) > len) {
2970 DEBUG_r(PerlIO_printf(Perl_debug_log, "String shorter than min possible regex match (%"
2971 UVuf " < %" IVdf ")\n",
2972 (UV)len, (IV)RXp_MINLEN(prog)));
2976 /* get pos() if //g */
2978 mg = mg_find_mglob(TARG);
2979 if (mg && mg->mg_len >= 0) {
2980 curpos = MgBYTEPOS(mg, TARG, truebase, len);
2981 /* last time pos() was set, it was zero-length match */
2982 if (mg->mg_flags & MGf_MINMATCH)
2987 #ifdef PERL_SAWAMPERSAND
2988 if ( RXp_NPARENS(prog)
2990 || (RXp_EXTFLAGS(prog) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
2991 || (dynpm->op_pmflags & PMf_KEEPCOPY)
2995 r_flags |= (REXEC_COPY_STR|REXEC_COPY_SKIP_PRE);
2996 /* in @a =~ /(.)/g, we iterate multiple times, but copy the buffer
2997 * only on the first iteration. Therefore we need to copy $' as well
2998 * as $&, to make the rest of the string available for captures in
2999 * subsequent iterations */
3000 if (! (global && gimme == G_ARRAY))
3001 r_flags |= REXEC_COPY_SKIP_POST;
3003 #ifdef PERL_SAWAMPERSAND
3004 if (dynpm->op_pmflags & PMf_KEEPCOPY)
3005 /* handle KEEPCOPY in pmop but not rx, eg $r=qr/a/; /$r/p */
3006 r_flags &= ~(REXEC_COPY_SKIP_PRE|REXEC_COPY_SKIP_POST);
3013 s = truebase + curpos;
3015 if (!CALLREGEXEC(rx, (char*)s, (char *)strend, (char*)truebase,
3016 had_zerolen, TARG, NULL, r_flags))
3020 if (dynpm->op_pmflags & PMf_ONCE)
3022 SvREADONLY_on(PL_regex_pad[dynpm->op_pmoffset]);
3024 dynpm->op_pmflags |= PMf_USED;
3028 RXp_MATCH_TAINTED_on(prog);
3029 TAINT_IF(RXp_MATCH_TAINTED(prog));
3033 if (global && (gimme != G_ARRAY || (dynpm->op_pmflags & PMf_CONTINUE))) {
3035 mg = sv_magicext_mglob(TARG);
3036 MgBYTEPOS_set(mg, TARG, truebase, RXp_OFFS(prog)[0].end);
3037 if (RXp_ZERO_LEN(prog))
3038 mg->mg_flags |= MGf_MINMATCH;
3040 mg->mg_flags &= ~MGf_MINMATCH;
3043 if ((!RXp_NPARENS(prog) && !global) || gimme != G_ARRAY) {
3044 LEAVE_SCOPE(oldsave);
3048 /* push captures on stack */
3051 const I32 nparens = RXp_NPARENS(prog);
3052 I32 i = (global && !nparens) ? 1 : 0;
3054 SPAGAIN; /* EVAL blocks could move the stack. */
3055 EXTEND(SP, nparens + i);
3056 EXTEND_MORTAL(nparens + i);
3057 for (i = !i; i <= nparens; i++) {
3058 PUSHs(sv_newmortal());
3059 if (LIKELY((RXp_OFFS(prog)[i].start != -1)
3060 && RXp_OFFS(prog)[i].end != -1 ))
3062 const I32 len = RXp_OFFS(prog)[i].end - RXp_OFFS(prog)[i].start;
3063 const char * const s = RXp_OFFS(prog)[i].start + truebase;
3064 if (UNLIKELY( RXp_OFFS(prog)[i].end < 0
3065 || RXp_OFFS(prog)[i].start < 0
3067 || len > strend - s)
3069 DIE(aTHX_ "panic: pp_match start/end pointers, i=%ld, "
3070 "start=%ld, end=%ld, s=%p, strend=%p, len=%" UVuf,
3071 (long) i, (long) RXp_OFFS(prog)[i].start,
3072 (long)RXp_OFFS(prog)[i].end, s, strend, (UV) len);
3073 sv_setpvn(*SP, s, len);
3074 if (DO_UTF8(TARG) && is_utf8_string((U8*)s, len))
3079 curpos = (UV)RXp_OFFS(prog)[0].end;
3080 had_zerolen = RXp_ZERO_LEN(prog);
3081 PUTBACK; /* EVAL blocks may use stack */
3082 r_flags |= REXEC_IGNOREPOS | REXEC_NOT_FIRST;
3085 LEAVE_SCOPE(oldsave);
3088 NOT_REACHED; /* NOTREACHED */
3091 if (global && !(dynpm->op_pmflags & PMf_CONTINUE)) {
3093 mg = mg_find_mglob(TARG);
3097 LEAVE_SCOPE(oldsave);
3098 if (gimme == G_ARRAY)
3104 Perl_do_readline(pTHX)
3106 dSP; dTARGETSTACKED;
3111 IO * const io = GvIO(PL_last_in_gv);
3112 const I32 type = PL_op->op_type;
3113 const U8 gimme = GIMME_V;
3116 const MAGIC *const mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar);
3118 Perl_tied_method(aTHX_ SV_CONST(READLINE), SP, MUTABLE_SV(io), mg, gimme, 0);
3119 if (gimme == G_SCALAR) {
3121 SvSetSV_nosteal(TARG, TOPs);
3131 if (IoFLAGS(io) & IOf_ARGV) {
3132 if (IoFLAGS(io) & IOf_START) {
3134 if (av_tindex(GvAVn(PL_last_in_gv)) < 0) {
3135 IoFLAGS(io) &= ~IOf_START;
3136 do_open6(PL_last_in_gv, "-", 1, NULL, NULL, 0);
3137 SvTAINTED_off(GvSVn(PL_last_in_gv)); /* previous tainting irrelevant */
3138 sv_setpvs(GvSVn(PL_last_in_gv), "-");
3139 SvSETMAGIC(GvSV(PL_last_in_gv));
3144 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
3145 if (!fp) { /* Note: fp != IoIFP(io) */
3146 (void)do_close(PL_last_in_gv, FALSE); /* now it does*/
3149 else if (type == OP_GLOB)
3150 fp = Perl_start_glob(aTHX_ POPs, io);
3152 else if (type == OP_GLOB)
3154 else if (IoTYPE(io) == IoTYPE_WRONLY) {
3155 report_wrongway_fh(PL_last_in_gv, '>');
3159 if ((!io || !(IoFLAGS(io) & IOf_START))
3160 && ckWARN(WARN_CLOSED)
3163 report_evil_fh(PL_last_in_gv);
3165 if (gimme == G_SCALAR) {
3166 /* undef TARG, and push that undefined value */
3167 if (type != OP_RCATLINE) {
3175 if (gimme == G_SCALAR) {
3177 if (type == OP_RCATLINE && SvGMAGICAL(sv))
3180 if (type == OP_RCATLINE)
3181 SvPV_force_nomg_nolen(sv);
3185 else if (isGV_with_GP(sv)) {
3186 SvPV_force_nomg_nolen(sv);
3188 SvUPGRADE(sv, SVt_PV);
3189 tmplen = SvLEN(sv); /* remember if already alloced */
3190 if (!tmplen && !SvREADONLY(sv) && !SvIsCOW(sv)) {
3191 /* try short-buffering it. Please update t/op/readline.t
3192 * if you change the growth length.
3197 if (type == OP_RCATLINE && SvOK(sv)) {
3199 SvPV_force_nomg_nolen(sv);
3205 sv = sv_2mortal(newSV(80));
3209 /* This should not be marked tainted if the fp is marked clean */
3210 #define MAYBE_TAINT_LINE(io, sv) \
3211 if (!(IoFLAGS(io) & IOf_UNTAINT)) { \
3216 /* delay EOF state for a snarfed empty file */
3217 #define SNARF_EOF(gimme,rs,io,sv) \
3218 (gimme != G_SCALAR || SvCUR(sv) \
3219 || (IoFLAGS(io) & IOf_NOLINE) || !RsSNARF(rs))
3223 if (!sv_gets(sv, fp, offset)
3225 || SNARF_EOF(gimme, PL_rs, io, sv)
3226 || PerlIO_error(fp)))
3228 PerlIO_clearerr(fp);
3229 if (IoFLAGS(io) & IOf_ARGV) {
3230 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
3233 (void)do_close(PL_last_in_gv, FALSE);
3235 else if (type == OP_GLOB) {
3236 if (!do_close(PL_last_in_gv, FALSE)) {
3237 Perl_ck_warner(aTHX_ packWARN(WARN_GLOB),
3238 "glob failed (child exited with status %d%s)",
3239 (int)(STATUS_CURRENT >> 8),
3240 (STATUS_CURRENT & 0x80) ? ", core dumped" : "");
3243 if (gimme == G_SCALAR) {
3244 if (type != OP_RCATLINE) {
3245 SV_CHECK_THINKFIRST_COW_DROP(TARG);
3251 MAYBE_TAINT_LINE(io, sv);
3254 MAYBE_TAINT_LINE(io, sv);
3256 IoFLAGS(io) |= IOf_NOLINE;
3260 if (type == OP_GLOB) {
3264 if (SvCUR(sv) > 0 && SvCUR(PL_rs) > 0) {
3265 char * const tmps = SvEND(sv) - 1;
3266 if (*tmps == *SvPVX_const(PL_rs)) {
3268 SvCUR_set(sv, SvCUR(sv) - 1);
3271 for (t1 = SvPVX_const(sv); *t1; t1++)
3273 if (strchr("*%?", *t1))
3275 if (strchr("$&*(){}[]'\";\\|?<>~`", *t1))
3278 if (*t1 && PerlLIO_lstat(SvPVX_const(sv), &statbuf) < 0) {
3279 (void)POPs; /* Unmatched wildcard? Chuck it... */
3282 } else if (SvUTF8(sv)) { /* OP_READLINE, OP_RCATLINE */
3283 if (ckWARN(WARN_UTF8)) {
3284 const U8 * const s = (const U8*)SvPVX_const(sv) + offset;
3285 const STRLEN len = SvCUR(sv) - offset;
3288 if (!is_utf8_string_loc(s, len, &f))
3289 /* Emulate :encoding(utf8) warning in the same case. */
3290 Perl_warner(aTHX_ packWARN(WARN_UTF8),
3291 "utf8 \"\\x%02X\" does not map to Unicode",
3292 f < (U8*)SvEND(sv) ? *f : 0);
3295 if (gimme == G_ARRAY) {
3296 if (SvLEN(sv) - SvCUR(sv) > 20) {
3297 SvPV_shrink_to_cur(sv);
3299 sv = sv_2mortal(newSV(80));
3302 else if (gimme == G_SCALAR && !tmplen && SvLEN(sv) - SvCUR(sv) > 80) {
3303 /* try to reclaim a bit of scalar space (only on 1st alloc) */
3304 const STRLEN new_len
3305 = SvCUR(sv) < 60 ? 80 : SvCUR(sv)+40; /* allow some slop */
3306 SvPV_renew(sv, new_len);
3317 SV * const keysv = POPs;
3318 HV * const hv = MUTABLE_HV(POPs);
3319 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
3320 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
3322 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
3323 bool preeminent = TRUE;
3325 if (SvTYPE(hv) != SVt_PVHV)
3332 /* If we can determine whether the element exist,
3333 * Try to preserve the existenceness of a tied hash
3334 * element by using EXISTS and DELETE if possible.
3335 * Fallback to FETCH and STORE otherwise. */
3336 if (SvCANEXISTDELETE(hv))
3337 preeminent = hv_exists_ent(hv, keysv, 0);
3340 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
3341 svp = he ? &HeVAL(he) : NULL;
3343 if (!svp || !*svp || *svp == &PL_sv_undef) {
3347 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
3349 lv = sv_newmortal();
3350 sv_upgrade(lv, SVt_PVLV);
3352 sv_magic(lv, key2 = newSVsv(keysv), PERL_MAGIC_defelem, NULL, 0);
3353 SvREFCNT_dec_NN(key2); /* sv_magic() increments refcount */
3354 LvTARG(lv) = SvREFCNT_inc_simple_NN(hv);
3360 if (HvNAME_get(hv) && isGV_or_RVCV(*svp))
3361 save_gp(MUTABLE_GV(*svp), !(PL_op->op_flags & OPf_SPECIAL));
3362 else if (preeminent)
3363 save_helem_flags(hv, keysv, svp,
3364 (PL_op->op_flags & OPf_SPECIAL) ? 0 : SAVEf_SETMAGIC);
3366 SAVEHDELETE(hv, keysv);
3368 else if (PL_op->op_private & OPpDEREF) {
3369 PUSHs(vivify_ref(*svp, PL_op->op_private & OPpDEREF));
3373 sv = (svp && *svp ? *svp : &PL_sv_undef);
3374 /* Originally this did a conditional C<sv = sv_mortalcopy(sv)>; this
3375 * was to make C<local $tied{foo} = $tied{foo}> possible.
3376 * However, it seems no longer to be needed for that purpose, and
3377 * introduced a new bug: stuff like C<while ($hash{taintedval} =~ /.../g>
3378 * would loop endlessly since the pos magic is getting set on the
3379 * mortal copy and lost. However, the copy has the effect of
3380 * triggering the get magic, and losing it altogether made things like
3381 * c<$tied{foo};> in void context no longer do get magic, which some
3382 * code relied on. Also, delayed triggering of magic on @+ and friends
3383 * meant the original regex may be out of scope by now. So as a
3384 * compromise, do the get magic here. (The MGf_GSKIP flag will stop it
3385 * being called too many times). */
3386 if (!lval && SvRMAGICAL(hv) && SvGMAGICAL(sv))
3393 /* a stripped-down version of Perl_softref2xv() for use by
3394 * pp_multideref(), which doesn't use PL_op->op_flags */
3397 S_softref2xv_lite(pTHX_ SV *const sv, const char *const what,
3400 if (PL_op->op_private & HINT_STRICT_REFS) {
3402 Perl_die(aTHX_ PL_no_symref_sv, sv,
3403 (SvPOKp(sv) && SvCUR(sv)>32 ? "..." : ""), what);
3405 Perl_die(aTHX_ PL_no_usym, what);
3408 Perl_die(aTHX_ PL_no_usym, what);
3409 return gv_fetchsv_nomg(sv, GV_ADD, type);
3413 /* Handle one or more aggregate derefs and array/hash indexings, e.g.
3414 * $h->{foo} or $a[0]{$key}[$i] or f()->[1]
3416 * op_aux points to an array of unions of UV / IV / SV* / PADOFFSET.
3417 * Each of these either contains a set of actions, or an argument, such as
3418 * an IV to use as an array index, or a lexical var to retrieve.
3419 * Several actions re stored per UV; we keep shifting new actions off the
3420 * one UV, and only reload when it becomes zero.
3425 SV *sv = NULL; /* init to avoid spurious 'may be used uninitialized' */
3426 UNOP_AUX_item *items = cUNOP_AUXx(PL_op)->op_aux;
3427 UV actions = items->uv;
3430 /* this tells find_uninit_var() where we're up to */
3431 PL_multideref_pc = items;
3434 /* there are three main classes of action; the first retrieve
3435 * the initial AV or HV from a variable or the stack; the second
3436 * does the equivalent of an unrolled (/DREFAV, rv2av, aelem),
3437 * the third an unrolled (/DREFHV, rv2hv, helem).
3439 switch (actions & MDEREF_ACTION_MASK) {
3442 actions = (++items)->uv;
3445 case MDEREF_AV_padav_aelem: /* $lex[...] */
3446 sv = PAD_SVl((++items)->pad_offset);
3449 case MDEREF_AV_gvav_aelem: /* $pkg[...] */
3450 sv = UNOP_AUX_item_sv(++items);
3451 assert(isGV_with_GP(sv));
3452 sv = (SV*)GvAVn((GV*)sv);
3455 case MDEREF_AV_pop_rv2av_aelem: /* expr->[...] */
3460 goto do_AV_rv2av_aelem;
3463 case MDEREF_AV_gvsv_vivify_rv2av_aelem: /* $pkg->[...] */
3464 sv = UNOP_AUX_item_sv(++items);
3465 assert(isGV_with_GP(sv));
3466 sv = GvSVn((GV*)sv);
3467 goto do_AV_vivify_rv2av_aelem;
3469 case MDEREF_AV_padsv_vivify_rv2av_aelem: /* $lex->[...] */
3470 sv = PAD_SVl((++items)->pad_offset);
3473 do_AV_vivify_rv2av_aelem:
3474 case MDEREF_AV_vivify_rv2av_aelem: /* vivify, ->[...] */
3475 /* this is the OPpDEREF action normally found at the end of
3476 * ops like aelem, helem, rv2sv */
3477 sv = vivify_ref(sv, OPpDEREF_AV);
3481 /* this is basically a copy of pp_rv2av when it just has the
3484 if (LIKELY(SvROK(sv))) {
3485 if (UNLIKELY(SvAMAGIC(sv))) {
3486 sv = amagic_deref_call(sv, to_av_amg);
3489 if (UNLIKELY(SvTYPE(sv) != SVt_PVAV))
3490 DIE(aTHX_ "Not an ARRAY reference");
3492 else if (SvTYPE(sv) != SVt_PVAV) {
3493 if (!isGV_with_GP(sv))
3494 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "an ARRAY", SVt_PVAV);
3495 sv = MUTABLE_SV(GvAVn((GV*)sv));
3501 /* retrieve the key; this may be either a lexical or package
3502 * var (whose index/ptr is stored as an item) or a signed
3503 * integer constant stored as an item.
3506 IV elem = 0; /* to shut up stupid compiler warnings */
3509 assert(SvTYPE(sv) == SVt_PVAV);
3511 switch (actions & MDEREF_INDEX_MASK) {
3512 case MDEREF_INDEX_none:
3514 case MDEREF_INDEX_const:
3515 elem = (++items)->iv;
3517 case MDEREF_INDEX_padsv:
3518 elemsv = PAD_SVl((++items)->pad_offset);
3520 case MDEREF_INDEX_gvsv:
3521 elemsv = UNOP_AUX_item_sv(++items);
3522 assert(isGV_with_GP(elemsv));
3523 elemsv = GvSVn((GV*)elemsv);
3525 if (UNLIKELY(SvROK(elemsv) && !SvGAMAGIC(elemsv)
3526 && ckWARN(WARN_MISC)))
3527 Perl_warner(aTHX_ packWARN(WARN_MISC),
3528 "Use of reference \"%" SVf "\" as array index",
3530 /* the only time that S_find_uninit_var() needs this
3531 * is to determine which index value triggered the
3532 * undef warning. So just update it here. Note that
3533 * since we don't save and restore this var (e.g. for
3534 * tie or overload execution), its value will be
3535 * meaningless apart from just here */
3536 PL_multideref_pc = items;
3537 elem = SvIV(elemsv);
3542 /* this is basically a copy of pp_aelem with OPpDEREF skipped */
3544 if (!(actions & MDEREF_FLAG_last)) {
3545 SV** svp = av_fetch((AV*)sv, elem, 1);
3546 if (!svp || ! (sv=*svp))
3547 DIE(aTHX_ PL_no_aelem, elem);
3551 if (PL_op->op_private &
3552 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
3554 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
3555 sv = av_exists((AV*)sv, elem) ? &PL_sv_yes : &PL_sv_no;
3558 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
3559 sv = av_delete((AV*)sv, elem, discard);
3567 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
3568 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
3569 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
3570 bool preeminent = TRUE;
3571 AV *const av = (AV*)sv;
3574 if (UNLIKELY(localizing)) {
3578 /* If we can determine whether the element exist,
3579 * Try to preserve the existenceness of a tied array
3580 * element by using EXISTS and DELETE if possible.
3581 * Fallback to FETCH and STORE otherwise. */
3582 if (SvCANEXISTDELETE(av))
3583 preeminent = av_exists(av, elem);
3586 svp = av_fetch(av, elem, lval && !defer);
3589 if (!svp || !(sv = *svp)) {
3592 DIE(aTHX_ PL_no_aelem, elem);
3593 len = av_tindex(av);
3594 /* Resolve a negative index that falls within
3595 * the array. Leave it negative it if falls
3596 * outside the array. */
3597 if (elem < 0 && len + elem >= 0)
3599 if (elem >= 0 && elem <= len)
3600 /* Falls within the array. */
3601 sv = av_nonelem(av,elem);
3603 /* Falls outside the array. If it is neg-
3604 ative, magic_setdefelem will use the
3605 index for error reporting. */
3606 sv = sv_2mortal(newSVavdefelem(av,elem,1));
3609 if (UNLIKELY(localizing)) {
3611 save_aelem(av, elem, svp);
3612 sv = *svp; /* may have changed */
3615 SAVEADELETE(av, elem);
3620 sv = (svp ? *svp : &PL_sv_undef);
3621 /* see note in pp_helem() */
3622 if (SvRMAGICAL(av) && SvGMAGICAL(sv))
3639 case MDEREF_HV_padhv_helem: /* $lex{...} */
3640 sv = PAD_SVl((++items)->pad_offset);
3643 case MDEREF_HV_gvhv_helem: /* $pkg{...} */
3644 sv = UNOP_AUX_item_sv(++items);
3645 assert(isGV_with_GP(sv));
3646 sv = (SV*)GvHVn((GV*)sv);
3649 case MDEREF_HV_pop_rv2hv_helem: /* expr->{...} */
3654 goto do_HV_rv2hv_helem;
3657 case MDEREF_HV_gvsv_vivify_rv2hv_helem: /* $pkg->{...} */
3658 sv = UNOP_AUX_item_sv(++items);
3659 assert(isGV_with_GP(sv));
3660 sv = GvSVn((GV*)sv);
3661 goto do_HV_vivify_rv2hv_helem;
3663 case MDEREF_HV_padsv_vivify_rv2hv_helem: /* $lex->{...} */
3664 sv = PAD_SVl((++items)->pad_offset);
3667 do_HV_vivify_rv2hv_helem:
3668 case MDEREF_HV_vivify_rv2hv_helem: /* vivify, ->{...} */
3669 /* this is the OPpDEREF action normally found at the end of
3670 * ops like aelem, helem, rv2sv */
3671 sv = vivify_ref(sv, OPpDEREF_HV);
3675 /* this is basically a copy of pp_rv2hv when it just has the
3676 * sKR/1 flags (and pp_rv2hv is aliased to pp_rv2av) */
3679 if (LIKELY(SvROK(sv))) {
3680 if (UNLIKELY(SvAMAGIC(sv))) {
3681 sv = amagic_deref_call(sv, to_hv_amg);
3684 if (UNLIKELY(SvTYPE(sv) != SVt_PVHV))
3685 DIE(aTHX_ "Not a HASH reference");
3687 else if (SvTYPE(sv) != SVt_PVHV) {
3688 if (!isGV_with_GP(sv))
3689 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "a HASH", SVt_PVHV);
3690 sv = MUTABLE_SV(GvHVn((GV*)sv));
3696 /* retrieve the key; this may be either a lexical / package
3697 * var or a string constant, whose index/ptr is stored as an
3700 SV *keysv = NULL; /* to shut up stupid compiler warnings */
3702 assert(SvTYPE(sv) == SVt_PVHV);
3704 switch (actions & MDEREF_INDEX_MASK) {
3705 case MDEREF_INDEX_none:
3708 case MDEREF_INDEX_const:
3709 keysv = UNOP_AUX_item_sv(++items);
3712 case MDEREF_INDEX_padsv:
3713 keysv = PAD_SVl((++items)->pad_offset);
3716 case MDEREF_INDEX_gvsv:
3717 keysv = UNOP_AUX_item_sv(++items);
3718 keysv = GvSVn((GV*)keysv);
3722 /* see comment above about setting this var */
3723 PL_multideref_pc = items;
3726 /* ensure that candidate CONSTs have been HEKified */
3727 assert( ((actions & MDEREF_INDEX_MASK) != MDEREF_INDEX_const)
3728 || SvTYPE(keysv) >= SVt_PVMG
3731 || SvIsCOW_shared_hash(keysv));
3733 /* this is basically a copy of pp_helem with OPpDEREF skipped */
3735 if (!(actions & MDEREF_FLAG_last)) {
3736 HE *he = hv_fetch_ent((HV*)sv, keysv, 1, 0);
3737 if (!he || !(sv=HeVAL(he)) || sv == &PL_sv_undef)
3738 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
3742 if (PL_op->op_private &
3743 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
3745 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
3746 sv = hv_exists_ent((HV*)sv, keysv, 0)
3747 ? &PL_sv_yes : &PL_sv_no;
3750 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
3751 sv = hv_delete_ent((HV*)sv, keysv, discard, 0);
3759 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
3760 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
3761 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
3762 bool preeminent = TRUE;
3764 HV * const hv = (HV*)sv;
3767 if (UNLIKELY(localizing)) {
3771 /* If we can determine whether the element exist,
3772 * Try to preserve the existenceness of a tied hash
3773 * element by using EXISTS and DELETE if possible.
3774 * Fallback to FETCH and STORE otherwise. */
3775 if (SvCANEXISTDELETE(hv))
3776 preeminent = hv_exists_ent(hv, keysv, 0);
3779 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
3780 svp = he ? &HeVAL(he) : NULL;
3784 if (!svp || !(sv = *svp) || sv == &PL_sv_undef) {
3788 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
3789 lv = sv_newmortal();
3790 sv_upgrade(lv, SVt_PVLV);
3792 sv_magic(lv, key2 = newSVsv(keysv),
3793 PERL_MAGIC_defelem, NULL, 0);
3794 /* sv_magic() increments refcount */
3795 SvREFCNT_dec_NN(key2);
3796 LvTARG(lv) = SvREFCNT_inc_simple_NN(hv);
3802 if (HvNAME_get(hv) && isGV_or_RVCV(sv))
3803 save_gp(MUTABLE_GV(sv),
3804 !(PL_op->op_flags & OPf_SPECIAL));
3805 else if (preeminent) {
3806 save_helem_flags(hv, keysv, svp,
3807 (PL_op->op_flags & OPf_SPECIAL)
3808 ? 0 : SAVEf_SETMAGIC);
3809 sv = *svp; /* may have changed */
3812 SAVEHDELETE(hv, keysv);
3817 sv = (svp && *svp ? *svp : &PL_sv_undef);
3818 /* see note in pp_helem() */
3819 if (SvRMAGICAL(hv) && SvGMAGICAL(sv))
3828 actions >>= MDEREF_SHIFT;
3846 itersvp = CxITERVAR(cx);
3849 switch (CxTYPE(cx)) {
3851 case CXt_LOOP_LAZYSV: /* string increment */
3853 SV* cur = cx->blk_loop.state_u.lazysv.cur;
3854 SV *end = cx->blk_loop.state_u.lazysv.end;
3855 /* If the maximum is !SvOK(), pp_enteriter substitutes PL_sv_no.
3856 It has SvPVX of "" and SvCUR of 0, which is what we want. */
3858 const char *max = SvPV_const(end, maxlen);
3859 if (DO_UTF8(end) && IN_UNI_8_BIT)
3860 maxlen = sv_len_utf8_nomg(end);
3861 if (UNLIKELY(SvNIOK(cur) || SvCUR(cur) > maxlen))
3865 /* NB: on the first iteration, oldsv will have a ref count of at
3866 * least 2 (one extra from blk_loop.itersave), so the GV or pad
3867 * slot will get localised; on subsequent iterations the RC==1
3868 * optimisation may kick in and the SV will be reused. */
3869 if (oldsv && LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
3870 /* safe to reuse old SV */
3871 sv_setsv(oldsv, cur);
3875 /* we need a fresh SV every time so that loop body sees a
3876 * completely new SV for closures/references to work as
3878 *itersvp = newSVsv(cur);
3879 SvREFCNT_dec(oldsv);
3881 if (strEQ(SvPVX_const(cur), max))
3882 sv_setiv(cur, 0); /* terminate next time */
3888 case CXt_LOOP_LAZYIV: /* integer increment */
3890 IV cur = cx->blk_loop.state_u.lazyiv.cur;
3891 if (UNLIKELY(cur > cx->blk_loop.state_u.lazyiv.end))
3895 /* see NB comment above */
3896 if (oldsv && LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
3897 /* safe to reuse old SV */
3899 if ( (SvFLAGS(oldsv) & (SVTYPEMASK|SVf_THINKFIRST|SVf_IVisUV))
3902 /* Cheap SvIOK_only().
3903 * Assert that flags which SvIOK_only() would test or
3904 * clear can't be set, because we're SVt_IV */
3905 assert(!(SvFLAGS(oldsv) &
3906 (SVf_OOK|SVf_UTF8|(SVf_OK & ~(SVf_IOK|SVp_IOK)))));
3907 SvFLAGS(oldsv) |= (SVf_IOK|SVp_IOK);
3908 /* SvIV_set() where sv_any points to head */
3909 oldsv->sv_u.svu_iv = cur;
3913 sv_setiv(oldsv, cur);
3917 /* we need a fresh SV every time so that loop body sees a
3918 * completely new SV for closures/references to work as they
3920 *itersvp = newSViv(cur);
3921 SvREFCNT_dec(oldsv);
3924 if (UNLIKELY(cur == IV_MAX)) {
3925 /* Handle end of range at IV_MAX */
3926 cx->blk_loop.state_u.lazyiv.end = IV_MIN;
3928 ++cx->blk_loop.state_u.lazyiv.cur;
3932 case CXt_LOOP_LIST: /* for (1,2,3) */
3934 assert(OPpITER_REVERSED == 2); /* so inc becomes -1 or 1 */
3935 inc = (IV)1 - (IV)(PL_op->op_private & OPpITER_REVERSED);
3936 ix = (cx->blk_loop.state_u.stack.ix += inc);
3937 if (UNLIKELY(inc > 0
3938 ? ix > cx->blk_oldsp
3939 : ix <= cx->blk_loop.state_u.stack.basesp)
3943 sv = PL_stack_base[ix];
3945 goto loop_ary_common;
3947 case CXt_LOOP_ARY: /* for (@ary) */
3949 av = cx->blk_loop.state_u.ary.ary;
3950 inc = (IV)1 - (IV)(PL_op->op_private & OPpITER_REVERSED);
3951 ix = (cx->blk_loop.state_u.ary.ix += inc);
3952 if (UNLIKELY(inc > 0
3958 if (UNLIKELY(SvRMAGICAL(av))) {
3959 SV * const * const svp = av_fetch(av, ix, FALSE);
3960 sv = svp ? *svp : NULL;
3963 sv = AvARRAY(av)[ix];
3968 if (UNLIKELY(cx->cx_type & CXp_FOR_LVREF)) {
3969 SvSetMagicSV(*itersvp, sv);
3974 if (UNLIKELY(SvIS_FREED(sv))) {
3976 Perl_croak(aTHX_ "Use of freed value in iteration");
3983 SvREFCNT_inc_simple_void_NN(sv);
3987 sv = newSVavdefelem(av, ix, 0);
3994 SvREFCNT_dec(oldsv);
3998 DIE(aTHX_ "panic: pp_iter, type=%u", CxTYPE(cx));
4001 /* Try to bypass pushing &PL_sv_yes and calling pp_and(); instead
4002 * jump straight to the AND op's op_other */
4003 assert(PL_op->op_next->op_type == OP_AND);
4004 if (PL_op->op_next->op_ppaddr == Perl_pp_and) {
4005 return cLOGOPx(PL_op->op_next)->op_other;
4008 /* An XS module has replaced the op_ppaddr, so fall back to the slow,
4010 /* pp_enteriter should have pre-extended the stack */
4011 EXTEND_SKIP(PL_stack_sp, 1);
4012 *++PL_stack_sp = &PL_sv_yes;
4013 return PL_op->op_next;
4017 /* Try to bypass pushing &PL_sv_no and calling pp_and(); instead
4018 * jump straight to the AND op's op_next */
4019 assert(PL_op->op_next->op_type == OP_AND);
4020 /* pp_enteriter should have pre-extended the stack */
4021 EXTEND_SKIP(PL_stack_sp, 1);
4022 /* we only need this for the rare case where the OP_AND isn't
4023 * in void context, e.g. $x = do { for (..) {...} };
4024 * (or for when an XS module has replaced the op_ppaddr)
4025 * but it's cheaper to just push it rather than testing first
4027 *++PL_stack_sp = &PL_sv_no;
4028 if (PL_op->op_next->op_ppaddr == Perl_pp_and) {
4029 return PL_op->op_next->op_next;
4032 /* An XS module has replaced the op_ppaddr, so fall back to the slow,
4034 return PL_op->op_next;
4040 A description of how taint works in pattern matching and substitution.
4042 This is all conditional on NO_TAINT_SUPPORT not being defined. Under
4043 NO_TAINT_SUPPORT, taint-related operations should become no-ops.
4045 While the pattern is being assembled/concatenated and then compiled,
4046 PL_tainted will get set (via TAINT_set) if any component of the pattern
4047 is tainted, e.g. /.*$tainted/. At the end of pattern compilation,
4048 the RXf_TAINTED flag is set on the pattern if PL_tainted is set (via
4049 TAINT_get). It will also be set if any component of the pattern matches
4050 based on locale-dependent behavior.
4052 When the pattern is copied, e.g. $r = qr/..../, the SV holding the ref to
4053 the pattern is marked as tainted. This means that subsequent usage, such
4054 as /x$r/, will set PL_tainted using TAINT_set, and thus RXf_TAINTED,
4055 on the new pattern too.
4057 RXf_TAINTED_SEEN is used post-execution by the get magic code
4058 of $1 et al to indicate whether the returned value should be tainted.
4059 It is the responsibility of the caller of the pattern (i.e. pp_match,
4060 pp_subst etc) to set this flag for any other circumstances where $1 needs
4063 The taint behaviour of pp_subst (and pp_substcont) is quite complex.
4065 There are three possible sources of taint
4067 * the pattern (both compile- and run-time, RXf_TAINTED / RXf_TAINTED_SEEN)
4068 * the replacement string (or expression under /e)
4070 There are four destinations of taint and they are affected by the sources
4071 according to the rules below:
4073 * the return value (not including /r):
4074 tainted by the source string and pattern, but only for the
4075 number-of-iterations case; boolean returns aren't tainted;
4076 * the modified string (or modified copy under /r):
4077 tainted by the source string, pattern, and replacement strings;
4079 tainted by the pattern, and under 'use re "taint"', by the source
4081 * PL_taint - i.e. whether subsequent code (e.g. in a /e block) is tainted:
4082 should always be unset before executing subsequent code.
4084 The overall action of pp_subst is:
4086 * at the start, set bits in rxtainted indicating the taint status of
4087 the various sources.
4089 * After each pattern execution, update the SUBST_TAINT_PAT bit in
4090 rxtainted if RXf_TAINTED_SEEN has been set, to indicate that the
4091 pattern has subsequently become tainted via locale ops.
4093 * If control is being passed to pp_substcont to execute a /e block,
4094 save rxtainted in the CXt_SUBST block, for future use by
4097 * Whenever control is being returned to perl code (either by falling
4098 off the "end" of pp_subst/pp_substcont, or by entering a /e block),
4099 use the flag bits in rxtainted to make all the appropriate types of
4100 destination taint visible; e.g. set RXf_TAINTED_SEEN so that $1
4101 et al will appear tainted.
4103 pp_match is just a simpler version of the above.
4119 U8 rxtainted = 0; /* holds various SUBST_TAINT_* flag bits.
4120 See "how taint works" above */
4123 REGEXP *rx = PM_GETRE(pm);
4124 regexp *prog = ReANY(rx);
4126 int force_on_match = 0;
4127 const I32 oldsave = PL_savestack_ix;
4129 bool doutf8 = FALSE; /* whether replacement is in utf8 */
4134 /* known replacement string? */
4135 SV *dstr = (pm->op_pmflags & PMf_CONST) ? POPs : NULL;
4139 if (PL_op->op_flags & OPf_STACKED)
4150 SvGETMAGIC(TARG); /* must come before cow check */
4152 /* note that a string might get converted to COW during matching */
4153 was_cow = cBOOL(SvIsCOW(TARG));
4155 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
4156 #ifndef PERL_ANY_COW
4158 sv_force_normal_flags(TARG,0);
4160 if ((SvREADONLY(TARG)
4161 || ( ((SvTYPE(TARG) == SVt_PVGV && isGV_with_GP(TARG))
4162 || SvTYPE(TARG) > SVt_PVLV)
4163 && !(SvTYPE(TARG) == SVt_PVGV && SvFAKE(TARG)))))
4164 Perl_croak_no_modify();
4168 orig = SvPV_nomg(TARG, len);
4169 /* note we don't (yet) force the var into being a string; if we fail
4170 * to match, we leave as-is; on successful match however, we *will*
4171 * coerce into a string, then repeat the match */
4172 if (!SvPOKp(TARG) || SvTYPE(TARG) == SVt_PVGV || SvVOK(TARG))
4175 /* only replace once? */
4176 once = !(rpm->op_pmflags & PMf_GLOBAL);
4178 /* See "how taint works" above */
4181 (SvTAINTED(TARG) ? SUBST_TAINT_STR : 0)
4182 | (RXp_ISTAINTED(prog) ? SUBST_TAINT_PAT : 0)
4183 | ((pm->op_pmflags & PMf_RETAINT) ? SUBST_TAINT_RETAINT : 0)
4184 | (( (once && !(rpm->op_pmflags & PMf_NONDESTRUCT))
4185 || (PL_op->op_private & OPpTRUEBOOL)) ? SUBST_TAINT_BOOLRET : 0));
4191 DIE(aTHX_ "panic: pp_subst, pm=%p, orig=%p", pm, orig);
4193 strend = orig + len;
4194 slen = DO_UTF8(TARG) ? utf8_length((U8*)orig, (U8*)strend) : len;
4195 maxiters = 2 * slen + 10; /* We can match twice at each
4196 position, once with zero-length,
4197 second time with non-zero. */
4199 /* handle the empty pattern */
4200 if (!RX_PRELEN(rx) && PL_curpm && !prog->mother_re) {
4201 if (PL_curpm == PL_reg_curpm) {
4202 if (PL_curpm_under) {
4203 if (PL_curpm_under == PL_reg_curpm) {
4204 Perl_croak(aTHX_ "Infinite recursion via empty pattern");
4206 pm = PL_curpm_under;
4216 #ifdef PERL_SAWAMPERSAND
4217 r_flags = ( RXp_NPARENS(prog)
4219 || (RXp_EXTFLAGS(prog) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
4220 || (rpm->op_pmflags & PMf_KEEPCOPY)
4225 r_flags = REXEC_COPY_STR;
4228 if (!CALLREGEXEC(rx, orig, strend, orig, 0, TARG, NULL, r_flags))
4231 PUSHs(rpm->op_pmflags & PMf_NONDESTRUCT ? TARG : &PL_sv_no);
4232 LEAVE_SCOPE(oldsave);
4237 /* known replacement string? */
4239 /* replacement needing upgrading? */
4240 if (DO_UTF8(TARG) && !doutf8) {
4241 nsv = sv_newmortal();
4243 sv_utf8_upgrade(nsv);
4244 c = SvPV_const(nsv, clen);
4248 c = SvPV_const(dstr, clen);
4249 doutf8 = DO_UTF8(dstr);
4252 if (UNLIKELY(TAINT_get))
4253 rxtainted |= SUBST_TAINT_REPL;
4260 /* can do inplace substitution? */
4265 && (I32)clen <= RXp_MINLENRET(prog)
4267 || !(r_flags & REXEC_COPY_STR)
4268 || (!SvGMAGICAL(dstr) && !(RXp_EXTFLAGS(prog) & RXf_EVAL_SEEN))
4270 && !(RXp_EXTFLAGS(prog) & RXf_NO_INPLACE_SUBST)
4271 && (!doutf8 || SvUTF8(TARG))
4272 && !(rpm->op_pmflags & PMf_NONDESTRUCT))
4276 /* string might have got converted to COW since we set was_cow */
4277 if (SvIsCOW(TARG)) {
4278 if (!force_on_match)
4280 assert(SvVOK(TARG));
4283 if (force_on_match) {
4284 /* redo the first match, this time with the orig var
4285 * forced into being a string */
4287 orig = SvPV_force_nomg(TARG, len);
4293 if (RXp_MATCH_TAINTED(prog)) /* run time pattern taint, eg locale */
4294 rxtainted |= SUBST_TAINT_PAT;
4295 m = orig + RXp_OFFS(prog)[0].start;
4296 d = orig + RXp_OFFS(prog)[0].end;
4298 if (m - s > strend - d) { /* faster to shorten from end */
4301 Copy(c, m, clen, char);
4306 Move(d, m, i, char);
4310 SvCUR_set(TARG, m - s);
4312 else { /* faster from front */
4316 Move(s, d - i, i, char);
4319 Copy(c, d, clen, char);
4326 d = s = RXp_OFFS(prog)[0].start + orig;
4329 if (UNLIKELY(iters++ > maxiters))
4330 DIE(aTHX_ "Substitution loop");
4331 /* run time pattern taint, eg locale */
4332 if (UNLIKELY(RXp_MATCH_TAINTED(prog)))
4333 rxtainted |= SUBST_TAINT_PAT;
4334 m = RXp_OFFS(prog)[0].start + orig;
4337 Move(s, d, i, char);
4341 Copy(c, d, clen, char);
4344 s = RXp_OFFS(prog)[0].end + orig;
4345 } while (CALLREGEXEC(rx, s, strend, orig,
4346 s == m, /* don't match same null twice */
4348 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
4351 SvCUR_set(TARG, d - SvPVX_const(TARG) + i);
4352 Move(s, d, i+1, char); /* include the NUL */
4356 if (PL_op->op_private & OPpTRUEBOOL)
4366 if (force_on_match) {
4367 /* redo the first match, this time with the orig var
4368 * forced into being a string */
4370 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
4371 /* I feel that it should be possible to avoid this mortal copy
4372 given that the code below copies into a new destination.
4373 However, I suspect it isn't worth the complexity of
4374 unravelling the C<goto force_it> for the small number of
4375 cases where it would be viable to drop into the copy code. */
4376 TARG = sv_2mortal(newSVsv(TARG));
4378 orig = SvPV_force_nomg(TARG, len);
4384 if (RXp_MATCH_TAINTED(prog)) /* run time pattern taint, eg locale */
4385 rxtainted |= SUBST_TAINT_PAT;
4387 s = RXp_OFFS(prog)[0].start + orig;
4388 dstr = newSVpvn_flags(orig, s-orig,
4389 SVs_TEMP | (DO_UTF8(TARG) ? SVf_UTF8 : 0));
4394 /* note that a whole bunch of local vars are saved here for
4395 * use by pp_substcont: here's a list of them in case you're
4396 * searching for places in this sub that uses a particular var:
4397 * iters maxiters r_flags oldsave rxtainted orig dstr targ
4398 * s m strend rx once */
4400 RETURNOP(cPMOP->op_pmreplrootu.op_pmreplroot);
4404 if (UNLIKELY(iters++ > maxiters))
4405 DIE(aTHX_ "Substitution loop");
4406 if (UNLIKELY(RXp_MATCH_TAINTED(prog)))
4407 rxtainted |= SUBST_TAINT_PAT;
4408 if (RXp_MATCH_COPIED(prog) && RXp_SUBBEG(prog) != orig) {
4410 char *old_orig = orig;
4411 assert(RXp_SUBOFFSET(prog) == 0);
4413 orig = RXp_SUBBEG(prog);
4414 s = orig + (old_s - old_orig);
4415 strend = s + (strend - old_s);
4417 m = RXp_OFFS(prog)[0].start + orig;
4418 sv_catpvn_nomg_maybeutf8(dstr, s, m - s, DO_UTF8(TARG));
4419 s = RXp_OFFS(prog)[0].end + orig;
4421 /* replacement already stringified */
4423 sv_catpvn_nomg_maybeutf8(dstr, c, clen, doutf8);
4427 sv_catsv(dstr, repl);
4431 } while (CALLREGEXEC(rx, s, strend, orig,
4432 s == m, /* Yields minend of 0 or 1 */
4434 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
4435 assert(strend >= s);
4436 sv_catpvn_nomg_maybeutf8(dstr, s, strend - s, DO_UTF8(TARG));
4438 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
4439 /* From here on down we're using the copy, and leaving the original
4446 /* The match may make the string COW. If so, brilliant, because
4447 that's just saved us one malloc, copy and free - the regexp has
4448 donated the old buffer, and we malloc an entirely new one, rather
4449 than the regexp malloc()ing a buffer and copying our original,
4450 only for us to throw it away here during the substitution. */
4451 if (SvIsCOW(TARG)) {
4452 sv_force_normal_flags(TARG, SV_COW_DROP_PV);
4458 SvPV_set(TARG, SvPVX(dstr));
4459 SvCUR_set(TARG, SvCUR(dstr));
4460 SvLEN_set(TARG, SvLEN(dstr));
4461 SvFLAGS(TARG) |= SvUTF8(dstr);
4462 SvPV_set(dstr, NULL);
4465 if (PL_op->op_private & OPpTRUEBOOL)
4472 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
4473 (void)SvPOK_only_UTF8(TARG);
4476 /* See "how taint works" above */
4478 if ((rxtainted & SUBST_TAINT_PAT) ||
4479 ((rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_RETAINT)) ==
4480 (SUBST_TAINT_STR|SUBST_TAINT_RETAINT))
4482 (RXp_MATCH_TAINTED_on(prog)); /* taint $1 et al */
4484 if (!(rxtainted & SUBST_TAINT_BOOLRET)
4485 && (rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT))
4487 SvTAINTED_on(TOPs); /* taint return value */
4489 SvTAINTED_off(TOPs); /* may have got tainted earlier */
4491 /* needed for mg_set below */
4493 cBOOL(rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT|SUBST_TAINT_REPL))
4497 SvSETMAGIC(TARG); /* PL_tainted must be correctly set for this mg_set */
4499 LEAVE_SCOPE(oldsave);
4509 PL_stack_base[PL_markstack_ptr[-1]++] = PL_stack_base[*PL_markstack_ptr];
4510 ++*PL_markstack_ptr;
4512 LEAVE_with_name("grep_item"); /* exit inner scope */
4515 if (UNLIKELY(PL_stack_base + *PL_markstack_ptr > SP)) {
4517 const U8 gimme = GIMME_V;
4519 LEAVE_with_name("grep"); /* exit outer scope */
4520 (void)POPMARK; /* pop src */
4521 items = --*PL_markstack_ptr - PL_markstack_ptr[-1];
4522 (void)POPMARK; /* pop dst */
4523 SP = PL_stack_base + POPMARK; /* pop original mark */
4524 if (gimme == G_SCALAR) {
4525 if (PL_op->op_private & OPpTRUEBOOL)
4526 PUSHs(items ? &PL_sv_yes : &PL_sv_zero);
4532 else if (gimme == G_ARRAY)
4539 ENTER_with_name("grep_item"); /* enter inner scope */
4542 src = PL_stack_base[TOPMARK];
4543 if (SvPADTMP(src)) {
4544 src = PL_stack_base[TOPMARK] = sv_mortalcopy(src);
4550 RETURNOP(cLOGOP->op_other);
4554 /* leave_adjust_stacks():
4556 * Process a scope's return args (in the range from_sp+1 .. PL_stack_sp),
4557 * positioning them at to_sp+1 onwards, and do the equivalent of a
4558 * FREEMPS and TAINT_NOT.
4560 * Not intended to be called in void context.
4562 * When leaving a sub, eval, do{} or other scope, the things that need
4563 * doing to process the return args are:
4564 * * in scalar context, only return the last arg (or PL_sv_undef if none);
4565 * * for the types of return that return copies of their args (such
4566 * as rvalue sub return), make a mortal copy of every return arg,
4567 * except where we can optimise the copy away without it being
4568 * semantically visible;
4569 * * make sure that the arg isn't prematurely freed; in the case of an
4570 * arg not copied, this may involve mortalising it. For example, in
4571 * C<sub f { my $x = ...; $x }>, $x would be freed when we do
4572 * CX_LEAVE_SCOPE(cx) unless it's protected or copied.
4574 * What condition to use when deciding whether to pass the arg through
4575 * or make a copy, is determined by the 'pass' arg; its valid values are:
4576 * 0: rvalue sub/eval exit
4577 * 1: other rvalue scope exit
4578 * 2: :lvalue sub exit in rvalue context
4579 * 3: :lvalue sub exit in lvalue context and other lvalue scope exits
4581 * There is a big issue with doing a FREETMPS. We would like to free any
4582 * temps created by the last statement which the sub executed, rather than
4583 * leaving them for the caller. In a situation where a sub call isn't
4584 * soon followed by a nextstate (e.g. nested recursive calls, a la
4585 * fibonacci()), temps can accumulate, causing memory and performance
4588 * On the other hand, we don't want to free any TEMPs which are keeping
4589 * alive any return args that we skipped copying; nor do we wish to undo
4590 * any mortalising done here.
4592 * The solution is to split the temps stack frame into two, with a cut
4593 * point delineating the two halves. We arrange that by the end of this
4594 * function, all the temps stack frame entries we wish to keep are in the
4595 * range PL_tmps_floor+1.. tmps_base-1, while the ones to free now are in
4596 * the range tmps_base .. PL_tmps_ix. During the course of this
4597 * function, tmps_base starts off as PL_tmps_floor+1, then increases
4598 * whenever we find or create a temp that we know should be kept. In
4599 * general the stuff above tmps_base is undecided until we reach the end,
4600 * and we may need a sort stage for that.
4602 * To determine whether a TEMP is keeping a return arg alive, every
4603 * arg that is kept rather than copied and which has the SvTEMP flag
4604 * set, has the flag temporarily unset, to mark it. At the end we scan
4605 * the temps stack frame above the cut for entries without SvTEMP and
4606 * keep them, while turning SvTEMP on again. Note that if we die before
4607 * the SvTEMPs flags are set again, its safe: at worst, subsequent use of
4608 * those SVs may be slightly less efficient.
4610 * In practice various optimisations for some common cases mean we can
4611 * avoid most of the scanning and swapping about with the temps stack.
4615 Perl_leave_adjust_stacks(pTHX_ SV **from_sp, SV **to_sp, U8 gimme, int pass)
4619 SSize_t tmps_base; /* lowest index into tmps stack that needs freeing now */
4622 PERL_ARGS_ASSERT_LEAVE_ADJUST_STACKS;
4626 if (gimme == G_ARRAY) {
4627 nargs = SP - from_sp;
4631 assert(gimme == G_SCALAR);
4632 if (UNLIKELY(from_sp >= SP)) {
4633 /* no return args */
4634 assert(from_sp == SP);
4636 *++SP = &PL_sv_undef;
4646 /* common code for G_SCALAR and G_ARRAY */
4648 tmps_base = PL_tmps_floor + 1;
4652 /* pointer version of tmps_base. Not safe across temp stack
4656 EXTEND_MORTAL(nargs); /* one big extend for worst-case scenario */
4657 tmps_basep = PL_tmps_stack + tmps_base;
4659 /* process each return arg */
4662 SV *sv = *from_sp++;
4664 assert(PL_tmps_ix + nargs < PL_tmps_max);
4666 /* PADTMPs with container set magic shouldn't appear in the
4667 * wild. This assert is more important for pp_leavesublv(),
4668 * but by testing for it here, we're more likely to catch
4669 * bad cases (what with :lvalue subs not being widely
4670 * deployed). The two issues are that for something like
4671 * sub :lvalue { $tied{foo} }
4673 * sub :lvalue { substr($foo,1,2) }
4674 * pp_leavesublv() will croak if the sub returns a PADTMP,
4675 * and currently functions like pp_substr() return a mortal
4676 * rather than using their PADTMP when returning a PVLV.
4677 * This is because the PVLV will hold a ref to $foo,
4678 * so $foo would get delayed in being freed while
4679 * the PADTMP SV remained in the PAD.
4680 * So if this assert fails it means either:
4681 * 1) there is pp code similar to pp_substr that is
4682 * returning a PADTMP instead of a mortal, and probably
4684 * 2) pp_leavesublv is making unwarranted assumptions
4685 * about always croaking on a PADTMP
4687 if (SvPADTMP(sv) && SvSMAGICAL(sv)) {
4689 for (mg = SvMAGIC(sv); mg; mg = mg->mg_moremagic) {
4690 assert(PERL_MAGIC_TYPE_IS_VALUE_MAGIC(mg->mg_type));
4696 pass == 0 ? (SvTEMP(sv) && !SvMAGICAL(sv) && SvREFCNT(sv) == 1)
4697 : pass == 1 ? ((SvTEMP(sv) || SvPADTMP(sv)) && !SvMAGICAL(sv) && SvREFCNT(sv) == 1)
4698 : pass == 2 ? (!SvPADTMP(sv))
4701 /* pass through: skip copy for logic or optimisation
4702 * reasons; instead mortalise it, except that ... */
4706 /* ... since this SV is an SvTEMP , we don't need to
4707 * re-mortalise it; instead we just need to ensure
4708 * that its existing entry in the temps stack frame
4709 * ends up below the cut and so avoids being freed
4710 * this time round. We mark it as needing to be kept
4711 * by temporarily unsetting SvTEMP; then at the end,
4712 * we shuffle any !SvTEMP entries on the tmps stack
4713 * back below the cut.
4714 * However, there's a significant chance that there's
4715 * a 1:1 correspondence between the first few (or all)
4716 * elements in the return args stack frame and those
4717 * in the temps stack frame; e,g.:
4718 * sub f { ....; map {...} .... },
4719 * or if we're exiting multiple scopes and one of the
4720 * inner scopes has already made mortal copies of each
4723 * If so, this arg sv will correspond to the next item
4724 * on the tmps stack above the cut, and so can be kept
4725 * merely by moving the cut boundary up one, rather
4726 * than messing with SvTEMP. If all args are 1:1 then
4727 * we can avoid the sorting stage below completely.
4729 * If there are no items above the cut on the tmps
4730 * stack, then the SvTEMP must comne from an item
4731 * below the cut, so there's nothing to do.
4733 if (tmps_basep <= &PL_tmps_stack[PL_tmps_ix]) {
4734 if (sv == *tmps_basep)
4740 else if (!SvPADTMP(sv)) {
4741 /* mortalise arg to avoid it being freed during save
4742 * stack unwinding. Pad tmps don't need mortalising as
4743 * they're never freed. This is the equivalent of
4744 * sv_2mortal(SvREFCNT_inc(sv)), except that:
4745 * * it assumes that the temps stack has already been
4747 * * it puts the new item at the cut rather than at
4748 * ++PL_tmps_ix, moving the previous occupant there
4751 if (!SvIMMORTAL(sv)) {
4752 SvREFCNT_inc_simple_void_NN(sv);
4754 /* Note that if there's nothing above the cut,
4755 * this copies the garbage one slot above
4756 * PL_tmps_ix onto itself. This is harmless (the
4757 * stack's already been extended), but might in
4758 * theory trigger warnings from tools like ASan
4760 PL_tmps_stack[++PL_tmps_ix] = *tmps_basep;
4766 /* Make a mortal copy of the SV.
4767 * The following code is the equivalent of sv_mortalcopy()
4769 * * it assumes the temps stack has already been extended;
4770 * * it optimises the copying for some simple SV types;
4771 * * it puts the new item at the cut rather than at
4772 * ++PL_tmps_ix, moving the previous occupant there
4775 SV *newsv = newSV(0);
4777 PL_tmps_stack[++PL_tmps_ix] = *tmps_basep;
4778 /* put it on the tmps stack early so it gets freed if we die */
4779 *tmps_basep++ = newsv;
4782 if (SvTYPE(sv) <= SVt_IV) {
4783 /* arg must be one of undef, IV/UV, or RV: skip
4784 * sv_setsv_flags() and do the copy directly */
4786 U32 srcflags = SvFLAGS(sv);
4788 assert(!SvGMAGICAL(sv));
4789 if (srcflags & (SVf_IOK|SVf_ROK)) {
4790 SET_SVANY_FOR_BODYLESS_IV(newsv);
4792 if (srcflags & SVf_ROK) {
4793 newsv->sv_u.svu_rv = SvREFCNT_inc(SvRV(sv));
4794 /* SV type plus flags */
4795 dstflags = (SVt_IV|SVf_ROK|SVs_TEMP);
4798 /* both src and dst are <= SVt_IV, so sv_any
4799 * points to the head; so access the heads
4800 * directly rather than going via sv_any.
4802 assert( &(sv->sv_u.svu_iv)
4803 == &(((XPVIV*) SvANY(sv))->xiv_iv));
4804 assert( &(newsv->sv_u.svu_iv)
4805 == &(((XPVIV*) SvANY(newsv))->xiv_iv));
4806 newsv->sv_u.svu_iv = sv->sv_u.svu_iv;
4807 /* SV type plus flags */
4808 dstflags = (SVt_IV|SVf_IOK|SVp_IOK|SVs_TEMP
4809 |(srcflags & SVf_IVisUV));
4813 assert(!(srcflags & SVf_OK));
4814 dstflags = (SVt_NULL|SVs_TEMP); /* SV type plus flags */
4816 SvFLAGS(newsv) = dstflags;
4820 /* do the full sv_setsv() */
4824 old_base = tmps_basep - PL_tmps_stack;
4826 sv_setsv_flags(newsv, sv, SV_DO_COW_SVSETSV);
4827 /* the mg_get or sv_setsv might have created new temps
4828 * or realloced the tmps stack; regrow and reload */
4829 EXTEND_MORTAL(nargs);
4830 tmps_basep = PL_tmps_stack + old_base;
4831 TAINT_NOT; /* Each item is independent */
4837 /* If there are any temps left above the cut, we need to sort
4838 * them into those to keep and those to free. The only ones to
4839 * keep are those for which we've temporarily unset SvTEMP.
4840 * Work inwards from the two ends at tmps_basep .. PL_tmps_ix,
4841 * swapping pairs as necessary. Stop when we meet in the middle.
4844 SV **top = PL_tmps_stack + PL_tmps_ix;
4845 while (tmps_basep <= top) {
4858 tmps_base = tmps_basep - PL_tmps_stack;
4861 PL_stack_sp = to_sp;
4863 /* unrolled FREETMPS() but using tmps_base-1 rather than PL_tmps_floor */
4864 while (PL_tmps_ix >= tmps_base) {
4865 SV* const sv = PL_tmps_stack[PL_tmps_ix--];
4867 PoisonWith(PL_tmps_stack + PL_tmps_ix + 1, 1, SV *, 0xAB);
4871 SvREFCNT_dec_NN(sv); /* note, can modify tmps_ix!!! */
4877 /* also tail-called by pp_return */
4887 assert(CxTYPE(cx) == CXt_SUB);
4889 if (CxMULTICALL(cx)) {
4890 /* entry zero of a stack is always PL_sv_undef, which
4891 * simplifies converting a '()' return into undef in scalar context */
4892 assert(PL_stack_sp > PL_stack_base || *PL_stack_base == &PL_sv_undef);
4896 gimme = cx->blk_gimme;
4897 oldsp = PL_stack_base + cx->blk_oldsp; /* last arg of previous frame */
4899 if (gimme == G_VOID)
4900 PL_stack_sp = oldsp;
4902 leave_adjust_stacks(oldsp, oldsp, gimme, 0);
4905 cx_popsub(cx); /* Stack values are safe: release CV and @_ ... */
4907 retop = cx->blk_sub.retop;
4914 /* clear (if possible) or abandon the current @_. If 'abandon' is true,
4915 * forces an abandon */
4918 Perl_clear_defarray(pTHX_ AV* av, bool abandon)
4920 const SSize_t fill = AvFILLp(av);
4922 PERL_ARGS_ASSERT_CLEAR_DEFARRAY;
4924 if (LIKELY(!abandon && SvREFCNT(av) == 1 && !SvMAGICAL(av))) {
4929 AV *newav = newAV();
4930 av_extend(newav, fill);
4931 AvREIFY_only(newav);
4932 PAD_SVl(0) = MUTABLE_SV(newav);
4933 SvREFCNT_dec_NN(av);
4944 I32 old_savestack_ix;
4949 /* Locate the CV to call:
4950 * - most common case: RV->CV: f(), $ref->():
4951 * note that if a sub is compiled before its caller is compiled,
4952 * the stash entry will be a ref to a CV, rather than being a GV.
4953 * - second most common case: CV: $ref->method()
4956 /* a non-magic-RV -> CV ? */
4957 if (LIKELY( (SvFLAGS(sv) & (SVf_ROK|SVs_GMG)) == SVf_ROK)) {
4958 cv = MUTABLE_CV(SvRV(sv));
4959 if (UNLIKELY(SvOBJECT(cv))) /* might be overloaded */
4963 cv = MUTABLE_CV(sv);
4966 if (UNLIKELY(SvTYPE(cv) != SVt_PVCV)) {
4967 /* handle all the weird cases */
4968 switch (SvTYPE(sv)) {
4970 if (!isGV_with_GP(sv))
4974 cv = GvCVu((const GV *)sv);
4975 if (UNLIKELY(!cv)) {
4977 cv = sv_2cv(sv, &stash, &gv, 0);
4979 old_savestack_ix = PL_savestack_ix;
4990 if (UNLIKELY(SvAMAGIC(sv))) {
4991 sv = amagic_deref_call(sv, to_cv_amg);
4992 /* Don't SPAGAIN here. */
4998 if (UNLIKELY(!SvOK(sv)))
4999 DIE(aTHX_ PL_no_usym, "a subroutine");
5001 sym = SvPV_nomg_const(sv, len);
5002 if (PL_op->op_private & HINT_STRICT_REFS)
5003 DIE(aTHX_ "Can't use string (\"%" SVf32 "\"%s) as a subroutine ref while \"strict refs\" in use", sv, len>32 ? "..." : "");
5004 cv = get_cvn_flags(sym, len, GV_ADD|SvUTF8(sv));
5007 cv = MUTABLE_CV(SvRV(sv));
5008 if (LIKELY(SvTYPE(cv) == SVt_PVCV))
5014 DIE(aTHX_ "Not a CODE reference");
5018 /* At this point we want to save PL_savestack_ix, either by doing a
5019 * cx_pushsub(), or for XS, doing an ENTER. But we don't yet know the final
5020 * CV we will be using (so we don't know whether its XS, so we can't
5021 * cx_pushsub() or ENTER yet), and determining cv may itself push stuff on
5022 * the save stack. So remember where we are currently on the save
5023 * stack, and later update the CX or scopestack entry accordingly. */
5024 old_savestack_ix = PL_savestack_ix;
5026 /* these two fields are in a union. If they ever become separate,
5027 * we have to test for both of them being null below */
5029 assert((void*)&CvROOT(cv) == (void*)&CvXSUB(cv));
5030 while (UNLIKELY(!CvROOT(cv))) {
5034 /* anonymous or undef'd function leaves us no recourse */
5035 if (CvLEXICAL(cv) && CvHASGV(cv))
5036 DIE(aTHX_ "Undefined subroutine &%" SVf " called",
5037 SVfARG(cv_name(cv, NULL, 0)));
5038 if (CvANON(cv) || !CvHASGV(cv)) {
5039 DIE(aTHX_ "Undefined subroutine called");
5042 /* autoloaded stub? */
5043 if (cv != GvCV(gv = CvGV(cv))) {
5046 /* should call AUTOLOAD now? */
5049 autogv = gv_autoload_pvn(GvSTASH(gv), GvNAME(gv), GvNAMELEN(gv),
5050 (GvNAMEUTF8(gv) ? SVf_UTF8 : 0)
5051 |(PL_op->op_flags & OPf_REF
5052 ? GV_AUTOLOAD_ISMETHOD
5054 cv = autogv ? GvCV(autogv) : NULL;
5057 sub_name = sv_newmortal();
5058 gv_efullname3(sub_name, gv, NULL);
5059 DIE(aTHX_ "Undefined subroutine &%" SVf " called", SVfARG(sub_name));
5063 /* unrolled "CvCLONE(cv) && ! CvCLONED(cv)" */
5064 if (UNLIKELY((CvFLAGS(cv) & (CVf_CLONE|CVf_CLONED)) == CVf_CLONE))
5065 DIE(aTHX_ "Closure prototype called");
5067 if (UNLIKELY((PL_op->op_private & OPpENTERSUB_DB) && GvCV(PL_DBsub)
5070 Perl_get_db_sub(aTHX_ &sv, cv);
5072 PL_curcopdb = PL_curcop;
5074 /* check for lsub that handles lvalue subroutines */
5075 cv = GvCV(gv_fetchpvs("DB::lsub", GV_ADDMULTI, SVt_PVCV));
5076 /* if lsub not found then fall back to DB::sub */
5077 if (!cv) cv = GvCV(PL_DBsub);
5079 cv = GvCV(PL_DBsub);
5082 if (!cv || (!CvXSUB(cv) && !CvSTART(cv)))
5083 DIE(aTHX_ "No DB::sub routine defined");
5086 if (!(CvISXSUB(cv))) {
5087 /* This path taken at least 75% of the time */
5094 /* keep PADTMP args alive throughout the call (we need to do this
5095 * because @_ isn't refcounted). Note that we create the mortals
5096 * in the caller's tmps frame, so they won't be freed until after
5097 * we return from the sub.
5106 *svp = sv = sv_mortalcopy(sv);
5112 cx = cx_pushblock(CXt_SUB, gimme, MARK, old_savestack_ix);
5113 hasargs = cBOOL(PL_op->op_flags & OPf_STACKED);
5114 cx_pushsub(cx, cv, PL_op->op_next, hasargs);
5116 padlist = CvPADLIST(cv);
5117 if (UNLIKELY((depth = ++CvDEPTH(cv)) >= 2))
5118 pad_push(padlist, depth);
5119 PAD_SET_CUR_NOSAVE(padlist, depth);
5120 if (LIKELY(hasargs)) {
5121 AV *const av = MUTABLE_AV(PAD_SVl(0));
5125 defavp = &GvAV(PL_defgv);
5126 cx->blk_sub.savearray = *defavp;
5127 *defavp = MUTABLE_AV(SvREFCNT_inc_simple_NN(av));
5129 /* it's the responsibility of whoever leaves a sub to ensure
5130 * that a clean, empty AV is left in pad[0]. This is normally
5131 * done by cx_popsub() */
5132 assert(!AvREAL(av) && AvFILLp(av) == -1);
5135 if (UNLIKELY(items - 1 > AvMAX(av))) {
5136 SV **ary = AvALLOC(av);
5137 Renew(ary, items, SV*);
5138 AvMAX(av) = items - 1;
5144 Copy(MARK+1,AvARRAY(av),items,SV*);
5145 AvFILLp(av) = items - 1;
5147 if (UNLIKELY((cx->blk_u16 & OPpENTERSUB_LVAL_MASK) == OPpLVAL_INTRO &&
5149 DIE(aTHX_ "Can't modify non-lvalue subroutine call of &%" SVf,
5150 SVfARG(cv_name(cv, NULL, 0)));
5151 /* warning must come *after* we fully set up the context
5152 * stuff so that __WARN__ handlers can safely dounwind()
5155 if (UNLIKELY(depth == PERL_SUB_DEPTH_WARN
5156 && ckWARN(WARN_RECURSION)
5157 && !(PERLDB_SUB && cv == GvCV(PL_DBsub))))
5158 sub_crush_depth(cv);
5159 RETURNOP(CvSTART(cv));
5162 SSize_t markix = TOPMARK;
5166 /* pretend we did the ENTER earlier */
5167 PL_scopestack[PL_scopestack_ix - 1] = old_savestack_ix;
5172 if (UNLIKELY(((PL_op->op_private
5173 & CX_PUSHSUB_GET_LVALUE_MASK(Perl_is_lvalue_sub)
5174 ) & OPpENTERSUB_LVAL_MASK) == OPpLVAL_INTRO &&
5176 DIE(aTHX_ "Can't modify non-lvalue subroutine call of &%" SVf,
5177 SVfARG(cv_name(cv, NULL, 0)));
5179 if (UNLIKELY(!(PL_op->op_flags & OPf_STACKED) && GvAV(PL_defgv))) {
5180 /* Need to copy @_ to stack. Alternative may be to
5181 * switch stack to @_, and copy return values
5182 * back. This would allow popping @_ in XSUB, e.g.. XXXX */
5183 AV * const av = GvAV(PL_defgv);
5184 const SSize_t items = AvFILL(av) + 1;
5188 const bool m = cBOOL(SvRMAGICAL(av));
5189 /* Mark is at the end of the stack. */
5191 for (; i < items; ++i)
5195 SV ** const svp = av_fetch(av, i, 0);
5196 sv = svp ? *svp : NULL;
5198 else sv = AvARRAY(av)[i];
5199 if (sv) SP[i+1] = sv;
5201 SP[i+1] = av_nonelem(av, i);
5209 SV **mark = PL_stack_base + markix;
5210 SSize_t items = SP - mark;
5213 if (*mark && SvPADTMP(*mark)) {
5214 *mark = sv_mortalcopy(*mark);
5218 /* We assume first XSUB in &DB::sub is the called one. */
5219 if (UNLIKELY(PL_curcopdb)) {
5220 SAVEVPTR(PL_curcop);
5221 PL_curcop = PL_curcopdb;
5224 /* Do we need to open block here? XXXX */
5226 /* calculate gimme here as PL_op might get changed and then not
5227 * restored until the LEAVE further down */
5228 is_scalar = (GIMME_V == G_SCALAR);
5230 /* CvXSUB(cv) must not be NULL because newXS() refuses NULL xsub address */
5232 CvXSUB(cv)(aTHX_ cv);
5234 #if defined DEBUGGING && !defined DEBUGGING_RE_ONLY
5235 /* This duplicates the check done in runops_debug(), but provides more
5236 * information in the common case of the fault being with an XSUB.
5238 * It should also catch an XSUB pushing more than it extends
5239 * in scalar context.
5241 if (PL_curstackinfo->si_stack_hwm < PL_stack_sp - PL_stack_base)
5242 Perl_croak_nocontext(
5243 "panic: XSUB %s::%s (%s) failed to extend arg stack: "
5244 "base=%p, sp=%p, hwm=%p\n",
5245 HvNAME(GvSTASH(CvGV(cv))), GvNAME(CvGV(cv)), CvFILE(cv),
5246 PL_stack_base, PL_stack_sp,
5247 PL_stack_base + PL_curstackinfo->si_stack_hwm);
5249 /* Enforce some sanity in scalar context. */
5251 SV **svp = PL_stack_base + markix + 1;
5252 if (svp != PL_stack_sp) {
5253 *svp = svp > PL_stack_sp ? &PL_sv_undef : *PL_stack_sp;
5263 Perl_sub_crush_depth(pTHX_ CV *cv)
5265 PERL_ARGS_ASSERT_SUB_CRUSH_DEPTH;
5268 Perl_warner(aTHX_ packWARN(WARN_RECURSION), "Deep recursion on anonymous subroutine");
5270 Perl_warner(aTHX_ packWARN(WARN_RECURSION), "Deep recursion on subroutine \"%" SVf "\"",
5271 SVfARG(cv_name(cv,NULL,0)));
5277 /* like croak, but report in context of caller */
5280 Perl_croak_caller(const char *pat, ...)
5284 const PERL_CONTEXT *cx = caller_cx(0, NULL);
5286 /* make error appear at call site */
5288 PL_curcop = cx->blk_oldcop;
5290 va_start(args, pat);
5292 NOT_REACHED; /* NOTREACHED */
5301 SV* const elemsv = POPs;
5302 IV elem = SvIV(elemsv);
5303 AV *const av = MUTABLE_AV(POPs);
5304 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
5305 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
5306 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
5307 bool preeminent = TRUE;
5310 if (UNLIKELY(SvROK(elemsv) && !SvGAMAGIC(elemsv) && ckWARN(WARN_MISC)))
5311 Perl_warner(aTHX_ packWARN(WARN_MISC),
5312 "Use of reference \"%" SVf "\" as array index",
5314 if (UNLIKELY(SvTYPE(av) != SVt_PVAV))
5317 if (UNLIKELY(localizing)) {
5321 /* If we can determine whether the element exist,
5322 * Try to preserve the existenceness of a tied array
5323 * element by using EXISTS and DELETE if possible.
5324 * Fallback to FETCH and STORE otherwise. */
5325 if (SvCANEXISTDELETE(av))
5326 preeminent = av_exists(av, elem);
5329 svp = av_fetch(av, elem, lval && !defer);
5331 #ifdef PERL_MALLOC_WRAP
5332 if (SvUOK(elemsv)) {
5333 const UV uv = SvUV(elemsv);
5334 elem = uv > IV_MAX ? IV_MAX : uv;
5336 else if (SvNOK(elemsv))
5337 elem = (IV)SvNV(elemsv);
5339 MEM_WRAP_CHECK_s(elem,SV*,"Out of memory during array extend");
5342 if (!svp || !*svp) {
5345 DIE(aTHX_ PL_no_aelem, elem);
5346 len = av_tindex(av);
5347 /* Resolve a negative index that falls within the array. Leave
5348 it negative it if falls outside the array. */
5349 if (elem < 0 && len + elem >= 0)
5351 if (elem >= 0 && elem <= len)
5352 /* Falls within the array. */
5353 PUSHs(av_nonelem(av,elem));
5355 /* Falls outside the array. If it is negative,
5356 magic_setdefelem will use the index for error reporting.
5358 mPUSHs(newSVavdefelem(av, elem, 1));
5361 if (UNLIKELY(localizing)) {
5363 save_aelem(av, elem, svp);
5365 SAVEADELETE(av, elem);
5367 else if (PL_op->op_private & OPpDEREF) {
5368 PUSHs(vivify_ref(*svp, PL_op->op_private & OPpDEREF));
5372 sv = (svp ? *svp : &PL_sv_undef);
5373 if (!lval && SvRMAGICAL(av) && SvGMAGICAL(sv)) /* see note in pp_helem() */
5380 Perl_vivify_ref(pTHX_ SV *sv, U32 to_what)
5382 PERL_ARGS_ASSERT_VIVIFY_REF;
5387 Perl_croak_no_modify();
5388 prepare_SV_for_RV(sv);
5391 SvRV_set(sv, newSV(0));
5394 SvRV_set(sv, MUTABLE_SV(newAV()));
5397 SvRV_set(sv, MUTABLE_SV(newHV()));
5404 if (SvGMAGICAL(sv)) {
5405 /* copy the sv without magic to prevent magic from being
5407 SV* msv = sv_newmortal();
5408 sv_setsv_nomg(msv, sv);
5414 PERL_STATIC_INLINE HV *
5415 S_opmethod_stash(pTHX_ SV* meth)
5420 SV* const sv = PL_stack_base + TOPMARK == PL_stack_sp
5421 ? (Perl_croak(aTHX_ "Can't call method \"%" SVf "\" without a "
5422 "package or object reference", SVfARG(meth)),
5424 : *(PL_stack_base + TOPMARK + 1);
5426 PERL_ARGS_ASSERT_OPMETHOD_STASH;
5430 Perl_croak(aTHX_ "Can't call method \"%" SVf "\" on an undefined value",
5433 if (UNLIKELY(SvGMAGICAL(sv))) mg_get(sv);
5434 else if (SvIsCOW_shared_hash(sv)) { /* MyClass->meth() */
5435 stash = gv_stashsv(sv, GV_CACHE_ONLY);
5436 if (stash) return stash;
5440 ob = MUTABLE_SV(SvRV(sv));
5441 else if (!SvOK(sv)) goto undefined;
5442 else if (isGV_with_GP(sv)) {
5444 Perl_croak(aTHX_ "Can't call method \"%" SVf "\" "
5445 "without a package or object reference",
5448 if (SvTYPE(ob) == SVt_PVLV && LvTYPE(ob) == 'y') {
5449 assert(!LvTARGLEN(ob));
5453 *(PL_stack_base + TOPMARK + 1) = sv_2mortal(newRV(ob));
5456 /* this isn't a reference */
5459 const char * const packname = SvPV_nomg_const(sv, packlen);
5460 const U32 packname_utf8 = SvUTF8(sv);
5461 stash = gv_stashpvn(packname, packlen, packname_utf8 | GV_CACHE_ONLY);
5462 if (stash) return stash;
5464 if (!(iogv = gv_fetchpvn_flags(
5465 packname, packlen, packname_utf8, SVt_PVIO
5467 !(ob=MUTABLE_SV(GvIO(iogv))))
5469 /* this isn't the name of a filehandle either */
5472 Perl_croak(aTHX_ "Can't call method \"%" SVf "\" "
5473 "without a package or object reference",
5476 /* assume it's a package name */
5477 stash = gv_stashpvn(packname, packlen, packname_utf8);
5478 if (stash) return stash;
5479 else return MUTABLE_HV(sv);
5481 /* it _is_ a filehandle name -- replace with a reference */
5482 *(PL_stack_base + TOPMARK + 1) = sv_2mortal(newRV(MUTABLE_SV(iogv)));
5485 /* if we got here, ob should be an object or a glob */
5486 if (!ob || !(SvOBJECT(ob)
5487 || (isGV_with_GP(ob)
5488 && (ob = MUTABLE_SV(GvIO((const GV *)ob)))
5491 Perl_croak(aTHX_ "Can't call method \"%" SVf "\" on unblessed reference",
5492 SVfARG((SvPOK(meth) && SvPVX(meth) == PL_isa_DOES)
5493 ? newSVpvs_flags("DOES", SVs_TEMP)
5505 SV* const meth = TOPs;
5508 SV* const rmeth = SvRV(meth);
5509 if (SvTYPE(rmeth) == SVt_PVCV) {
5515 stash = opmethod_stash(meth);
5517 gv = gv_fetchmethod_sv_flags(stash, meth, GV_AUTOLOAD|GV_CROAK);
5520 SETs(isGV(gv) ? MUTABLE_SV(GvCV(gv)) : MUTABLE_SV(gv));
5524 #define METHOD_CHECK_CACHE(stash,cache,meth) \
5525 const HE* const he = hv_fetch_ent(cache, meth, 0, 0); \
5527 gv = MUTABLE_GV(HeVAL(he)); \
5528 if (isGV(gv) && GvCV(gv) && (!GvCVGEN(gv) || GvCVGEN(gv) \
5529 == (PL_sub_generation + HvMROMETA(stash)->cache_gen))) \
5531 XPUSHs(MUTABLE_SV(GvCV(gv))); \
5540 SV* const meth = cMETHOPx_meth(PL_op);
5541 HV* const stash = opmethod_stash(meth);
5543 if (LIKELY(SvTYPE(stash) == SVt_PVHV)) {
5544 METHOD_CHECK_CACHE(stash, stash, meth);
5547 gv = gv_fetchmethod_sv_flags(stash, meth, GV_AUTOLOAD|GV_CROAK);
5550 XPUSHs(isGV(gv) ? MUTABLE_SV(GvCV(gv)) : MUTABLE_SV(gv));
5559 SV* const meth = cMETHOPx_meth(PL_op);
5560 HV* const stash = CopSTASH(PL_curcop);
5561 /* Actually, SUPER doesn't need real object's (or class') stash at all,
5562 * as it uses CopSTASH. However, we must ensure that object(class) is
5563 * correct (this check is done by S_opmethod_stash) */
5564 opmethod_stash(meth);
5566 if ((cache = HvMROMETA(stash)->super)) {
5567 METHOD_CHECK_CACHE(stash, cache, meth);
5570 gv = gv_fetchmethod_sv_flags(stash, meth, GV_AUTOLOAD|GV_CROAK|GV_SUPER);
5573 XPUSHs(isGV(gv) ? MUTABLE_SV(GvCV(gv)) : MUTABLE_SV(gv));
5581 SV* const meth = cMETHOPx_meth(PL_op);
5582 HV* stash = gv_stashsv(cMETHOPx_rclass(PL_op), 0);
5583 opmethod_stash(meth); /* not used but needed for error checks */
5585 if (stash) { METHOD_CHECK_CACHE(stash, stash, meth); }
5586 else stash = MUTABLE_HV(cMETHOPx_rclass(PL_op));
5588 gv = gv_fetchmethod_sv_flags(stash, meth, GV_AUTOLOAD|GV_CROAK);
5591 XPUSHs(isGV(gv) ? MUTABLE_SV(GvCV(gv)) : MUTABLE_SV(gv));
5595 PP(pp_method_redir_super)
5600 SV* const meth = cMETHOPx_meth(PL_op);
5601 HV* stash = gv_stashsv(cMETHOPx_rclass(PL_op), 0);
5602 opmethod_stash(meth); /* not used but needed for error checks */
5604 if (UNLIKELY(!stash)) stash = MUTABLE_HV(cMETHOPx_rclass(PL_op));
5605 else if ((cache = HvMROMETA(stash)->super)) {
5606 METHOD_CHECK_CACHE(stash, cache, meth);
5609 gv = gv_fetchmethod_sv_flags(stash, meth, GV_AUTOLOAD|GV_CROAK|GV_SUPER);
5612 XPUSHs(isGV(gv) ? MUTABLE_SV(GvCV(gv)) : MUTABLE_SV(gv));
5617 * ex: set ts=8 sts=4 sw=4 et: