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 $x .= sprintf(...)
1056 && ( !(PL_op->op_private & OPpMULTICONCAT_FAKE)
1060 SV * const tmpsv = amagic_call(left, right, concat_amg,
1061 (nextappend ? AMGf_assign: 0));
1063 /* NB: tryAMAGICbin_MG() includes an OPpTARGET_MY test
1064 * here, which isn't needed as any implicit
1065 * assign done under OPpTARGET_MY is done after
1068 sv_setsv(left, tmpsv);
1077 /* if both args are the same magical value, make one a copy */
1078 if (left == right && SvGMAGICAL(left)) {
1079 left = sv_newmortal();
1080 /* Print the uninitialized warning now, so it includes the
1083 if (ckWARN(WARN_UNINITIALIZED))
1084 report_uninit(right);
1085 sv_setsv_flags(left, &PL_sv_no, 0);
1088 sv_setsv_flags(left, right, 0);
1093 /* nexttarg = left . right */
1094 S_do_concat(aTHX_ left, right, nexttarg, 0);
1098 SP = toparg - stack_adj + 1;
1100 /* Return the result of all RHS concats, unless this op includes
1101 * an assign ($lex = x.y.z or expr = x.y.z), in which case copy
1102 * to target (which will be $lex or expr).
1103 * If we are appending, targ will already have been appended to in
1106 && ( (PL_op->op_flags & OPf_STACKED)
1107 || (PL_op->op_private & OPpTARGET_MY))
1109 sv_setsv(targ, left);
1120 /* push the elements of av onto the stack.
1121 * Returns PL_op->op_next to allow tail-call optimisation of its callers */
1124 S_pushav(pTHX_ AV* const av)
1127 const SSize_t maxarg = AvFILL(av) + 1;
1129 if (UNLIKELY(SvRMAGICAL(av))) {
1131 for (i=0; i < (PADOFFSET)maxarg; i++) {
1132 SV ** const svp = av_fetch(av, i, FALSE);
1133 SP[i+1] = LIKELY(svp)
1135 : UNLIKELY(PL_op->op_flags & OPf_MOD)
1142 for (i=0; i < (PADOFFSET)maxarg; i++) {
1143 SV *sv = AvARRAY(av)[i];
1144 SP[i+1] = LIKELY(sv)
1146 : UNLIKELY(PL_op->op_flags & OPf_MOD)
1157 /* ($lex1,@lex2,...) or my ($lex1,@lex2,...) */
1162 PADOFFSET base = PL_op->op_targ;
1163 int count = (int)(PL_op->op_private) & OPpPADRANGE_COUNTMASK;
1164 if (PL_op->op_flags & OPf_SPECIAL) {
1165 /* fake the RHS of my ($x,$y,..) = @_ */
1167 (void)S_pushav(aTHX_ GvAVn(PL_defgv));
1171 /* note, this is only skipped for compile-time-known void cxt */
1172 if ((PL_op->op_flags & OPf_WANT) != OPf_WANT_VOID) {
1177 for (i = 0; i <count; i++)
1178 *++SP = PAD_SV(base+i);
1180 if (PL_op->op_private & OPpLVAL_INTRO) {
1181 SV **svp = &(PAD_SVl(base));
1182 const UV payload = (UV)(
1183 (base << (OPpPADRANGE_COUNTSHIFT + SAVE_TIGHT_SHIFT))
1184 | (count << SAVE_TIGHT_SHIFT)
1185 | SAVEt_CLEARPADRANGE);
1188 STATIC_ASSERT_STMT(OPpPADRANGE_COUNTMASK + 1 == (1 << OPpPADRANGE_COUNTSHIFT));
1189 assert((payload >> (OPpPADRANGE_COUNTSHIFT+SAVE_TIGHT_SHIFT))
1197 for (i = 0; i <count; i++)
1198 SvPADSTALE_off(*svp++); /* mark lexical as active */
1209 OP * const op = PL_op;
1210 /* access PL_curpad once */
1211 SV ** const padentry = &(PAD_SVl(op->op_targ));
1216 PUTBACK; /* no pop/push after this, TOPs ok */
1218 if (op->op_flags & OPf_MOD) {
1219 if (op->op_private & OPpLVAL_INTRO)
1220 if (!(op->op_private & OPpPAD_STATE))
1221 save_clearsv(padentry);
1222 if (op->op_private & OPpDEREF) {
1223 /* TOPs is equivalent to TARG here. Using TOPs (SP) rather
1224 than TARG reduces the scope of TARG, so it does not
1225 span the call to save_clearsv, resulting in smaller
1227 TOPs = vivify_ref(TOPs, op->op_private & OPpDEREF);
1237 /* pp_coreargs pushes a NULL to indicate no args passed to
1238 * CORE::readline() */
1241 tryAMAGICunTARGETlist(iter_amg, 0);
1242 PL_last_in_gv = MUTABLE_GV(*PL_stack_sp--);
1244 else PL_last_in_gv = PL_argvgv, PL_stack_sp--;
1245 if (!isGV_with_GP(PL_last_in_gv)) {
1246 if (SvROK(PL_last_in_gv) && isGV_with_GP(SvRV(PL_last_in_gv)))
1247 PL_last_in_gv = MUTABLE_GV(SvRV(PL_last_in_gv));
1250 XPUSHs(MUTABLE_SV(PL_last_in_gv));
1252 Perl_pp_rv2gv(aTHX);
1253 PL_last_in_gv = MUTABLE_GV(*PL_stack_sp--);
1254 assert((SV*)PL_last_in_gv == &PL_sv_undef || isGV_with_GP(PL_last_in_gv));
1257 return do_readline();
1265 tryAMAGICbin_MG(eq_amg, AMGf_numeric);
1269 (SvIOK_notUV(left) && SvIOK_notUV(right))
1270 ? (SvIVX(left) == SvIVX(right))
1271 : ( do_ncmp(left, right) == 0)
1277 /* also used for: pp_i_preinc() */
1281 SV *sv = *PL_stack_sp;
1283 if (LIKELY(((sv->sv_flags &
1284 (SVf_THINKFIRST|SVs_GMG|SVf_IVisUV|
1285 SVf_IOK|SVf_NOK|SVf_POK|SVp_NOK|SVp_POK|SVf_ROK))
1287 && SvIVX(sv) != IV_MAX)
1289 SvIV_set(sv, SvIVX(sv) + 1);
1291 else /* Do all the PERL_PRESERVE_IVUV and hard cases in sv_inc */
1298 /* also used for: pp_i_predec() */
1302 SV *sv = *PL_stack_sp;
1304 if (LIKELY(((sv->sv_flags &
1305 (SVf_THINKFIRST|SVs_GMG|SVf_IVisUV|
1306 SVf_IOK|SVf_NOK|SVf_POK|SVp_NOK|SVp_POK|SVf_ROK))
1308 && SvIVX(sv) != IV_MIN)
1310 SvIV_set(sv, SvIVX(sv) - 1);
1312 else /* Do all the PERL_PRESERVE_IVUV and hard cases in sv_dec */
1319 /* also used for: pp_orassign() */
1330 if (PL_op->op_type == OP_OR)
1332 RETURNOP(cLOGOP->op_other);
1337 /* also used for: pp_dor() pp_dorassign() */
1344 const int op_type = PL_op->op_type;
1345 const bool is_dor = (op_type == OP_DOR || op_type == OP_DORASSIGN);
1350 if (UNLIKELY(!sv || !SvANY(sv))) {
1351 if (op_type == OP_DOR)
1353 RETURNOP(cLOGOP->op_other);
1359 if (UNLIKELY(!sv || !SvANY(sv)))
1364 switch (SvTYPE(sv)) {
1366 if (AvMAX(sv) >= 0 || SvGMAGICAL(sv) || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
1370 if (HvARRAY(sv) || SvGMAGICAL(sv) || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
1374 if (CvROOT(sv) || CvXSUB(sv))
1387 if(op_type == OP_DOR)
1389 RETURNOP(cLOGOP->op_other);
1391 /* assuming OP_DEFINED */
1401 dSP; dATARGET; bool useleft; SV *svl, *svr;
1403 tryAMAGICbin_MG(add_amg, AMGf_assign|AMGf_numeric);
1407 #ifdef PERL_PRESERVE_IVUV
1409 /* special-case some simple common cases */
1410 if (!((svl->sv_flags|svr->sv_flags) & (SVf_IVisUV|SVs_GMG))) {
1412 U32 flags = (svl->sv_flags & svr->sv_flags);
1413 if (flags & SVf_IOK) {
1414 /* both args are simple IVs */
1419 topl = ((UV)il) >> (UVSIZE * 8 - 2);
1420 topr = ((UV)ir) >> (UVSIZE * 8 - 2);
1422 /* if both are in a range that can't under/overflow, do a
1423 * simple integer add: if the top of both numbers
1424 * are 00 or 11, then it's safe */
1425 if (!( ((topl+1) | (topr+1)) & 2)) {
1427 TARGi(il + ir, 0); /* args not GMG, so can't be tainted */
1433 else if (flags & SVf_NOK) {
1434 /* both args are NVs */
1439 #if defined(NAN_COMPARE_BROKEN) && defined(Perl_isnan)
1440 !Perl_isnan(nl) && nl == (NV)(il = (IV)nl)
1441 && !Perl_isnan(nr) && nr == (NV)(ir = (IV)nr)
1443 nl == (NV)(il = (IV)nl) && nr == (NV)(ir = (IV)nr)
1446 /* nothing was lost by converting to IVs */
1449 TARGn(nl + nr, 0); /* args not GMG, so can't be tainted */
1457 useleft = USE_LEFT(svl);
1458 /* We must see if we can perform the addition with integers if possible,
1459 as the integer code detects overflow while the NV code doesn't.
1460 If either argument hasn't had a numeric conversion yet attempt to get
1461 the IV. It's important to do this now, rather than just assuming that
1462 it's not IOK as a PV of "9223372036854775806" may not take well to NV
1463 addition, and an SV which is NOK, NV=6.0 ought to be coerced to
1464 integer in case the second argument is IV=9223372036854775806
1465 We can (now) rely on sv_2iv to do the right thing, only setting the
1466 public IOK flag if the value in the NV (or PV) slot is truly integer.
1468 A side effect is that this also aggressively prefers integer maths over
1469 fp maths for integer values.
1471 How to detect overflow?
1473 C 99 section 6.2.6.1 says
1475 The range of nonnegative values of a signed integer type is a subrange
1476 of the corresponding unsigned integer type, and the representation of
1477 the same value in each type is the same. A computation involving
1478 unsigned operands can never overflow, because a result that cannot be
1479 represented by the resulting unsigned integer type is reduced modulo
1480 the number that is one greater than the largest value that can be
1481 represented by the resulting type.
1485 which I read as "unsigned ints wrap."
1487 signed integer overflow seems to be classed as "exception condition"
1489 If an exceptional condition occurs during the evaluation of an
1490 expression (that is, if the result is not mathematically defined or not
1491 in the range of representable values for its type), the behavior is
1494 (6.5, the 5th paragraph)
1496 I had assumed that on 2s complement machines signed arithmetic would
1497 wrap, hence coded pp_add and pp_subtract on the assumption that
1498 everything perl builds on would be happy. After much wailing and
1499 gnashing of teeth it would seem that irix64 knows its ANSI spec well,
1500 knows that it doesn't need to, and doesn't. Bah. Anyway, the all-
1501 unsigned code below is actually shorter than the old code. :-)
1504 if (SvIV_please_nomg(svr)) {
1505 /* Unless the left argument is integer in range we are going to have to
1506 use NV maths. Hence only attempt to coerce the right argument if
1507 we know the left is integer. */
1514 a_valid = auvok = 1;
1515 /* left operand is undef, treat as zero. + 0 is identity,
1516 Could SETi or SETu right now, but space optimise by not adding
1517 lots of code to speed up what is probably a rarish case. */
1519 /* Left operand is defined, so is it IV? */
1520 if (SvIV_please_nomg(svl)) {
1521 if ((auvok = SvUOK(svl)))
1524 const IV aiv = SvIVX(svl);
1527 auvok = 1; /* Now acting as a sign flag. */
1536 bool result_good = 0;
1539 bool buvok = SvUOK(svr);
1544 const IV biv = SvIVX(svr);
1551 /* ?uvok if value is >= 0. basically, flagged as UV if it's +ve,
1552 else "IV" now, independent of how it came in.
1553 if a, b represents positive, A, B negative, a maps to -A etc
1558 all UV maths. negate result if A negative.
1559 add if signs same, subtract if signs differ. */
1561 if (auvok ^ buvok) {
1565 /* Must get smaller */
1570 if (result <= buv) {
1571 /* result really should be -(auv-buv). as its negation
1572 of true value, need to swap our result flag */
1589 if (result <= (UV)IV_MIN)
1590 SETi(result == (UV)IV_MIN
1591 ? IV_MIN : -(IV)result);
1593 /* result valid, but out of range for IV. */
1594 SETn( -(NV)result );
1598 } /* Overflow, drop through to NVs. */
1603 useleft = USE_LEFT(svl);
1607 NV value = SvNV_nomg(svr);
1610 /* left operand is undef, treat as zero. + 0.0 is identity. */
1614 SETn( value + SvNV_nomg(svl) );
1620 /* also used for: pp_aelemfast_lex() */
1625 AV * const av = PL_op->op_type == OP_AELEMFAST_LEX
1626 ? MUTABLE_AV(PAD_SV(PL_op->op_targ)) : GvAVn(cGVOP_gv);
1627 const U32 lval = PL_op->op_flags & OPf_MOD;
1628 const I8 key = (I8)PL_op->op_private;
1632 assert(SvTYPE(av) == SVt_PVAV);
1636 /* inlined av_fetch() for simple cases ... */
1637 if (!SvRMAGICAL(av) && key >= 0 && key <= AvFILLp(av)) {
1638 sv = AvARRAY(av)[key];
1645 /* ... else do it the hard way */
1646 svp = av_fetch(av, key, lval);
1647 sv = (svp ? *svp : &PL_sv_undef);
1649 if (UNLIKELY(!svp && lval))
1650 DIE(aTHX_ PL_no_aelem, (int)key);
1652 if (!lval && SvRMAGICAL(av) && SvGMAGICAL(sv)) /* see note in pp_helem() */
1660 dSP; dMARK; dTARGET;
1662 do_join(TARG, *MARK, MARK, SP);
1668 /* Oversized hot code. */
1670 /* also used for: pp_say() */
1674 dSP; dMARK; dORIGMARK;
1678 = (PL_op->op_flags & OPf_STACKED) ? MUTABLE_GV(*++MARK) : PL_defoutgv;
1682 && (mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar)))
1685 if (MARK == ORIGMARK) {
1686 /* If using default handle then we need to make space to
1687 * pass object as 1st arg, so move other args up ...
1691 Move(MARK, MARK + 1, (SP - MARK) + 1, SV*);
1694 return Perl_tied_method(aTHX_ SV_CONST(PRINT), mark - 1, MUTABLE_SV(io),
1696 (G_SCALAR | TIED_METHOD_ARGUMENTS_ON_STACK
1697 | (PL_op->op_type == OP_SAY
1698 ? TIED_METHOD_SAY : 0)), sp - mark);
1701 if ( gv && GvEGVx(gv) && (io = GvIO(GvEGV(gv)))
1702 && (mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar)))
1705 SETERRNO(EBADF,RMS_IFI);
1708 else if (!(fp = IoOFP(io))) {
1710 report_wrongway_fh(gv, '<');
1713 SETERRNO(EBADF,IoIFP(io)?RMS_FAC:RMS_IFI);
1717 SV * const ofs = GvSV(PL_ofsgv); /* $, */
1719 if (ofs && (SvGMAGICAL(ofs) || SvOK(ofs))) {
1720 while (MARK <= SP) {
1721 if (!do_print(*MARK, fp))
1725 /* don't use 'ofs' here - it may be invalidated by magic callbacks */
1726 if (!do_print(GvSV(PL_ofsgv), fp)) {
1734 while (MARK <= SP) {
1735 if (!do_print(*MARK, fp))
1743 if (PL_op->op_type == OP_SAY) {
1744 if (PerlIO_write(fp, "\n", 1) == 0 || PerlIO_error(fp))
1747 else if (PL_ors_sv && SvOK(PL_ors_sv))
1748 if (!do_print(PL_ors_sv, fp)) /* $\ */
1751 if (IoFLAGS(io) & IOf_FLUSH)
1752 if (PerlIO_flush(fp) == EOF)
1762 XPUSHs(&PL_sv_undef);
1767 /* do the common parts of pp_padhv() and pp_rv2hv()
1768 * It assumes the caller has done EXTEND(SP, 1) or equivalent.
1769 * 'is_keys' indicates the OPpPADHV_ISKEYS/OPpRV2HV_ISKEYS flag is set.
1770 * 'has_targ' indicates that the op has a target - this should
1771 * be a compile-time constant so that the code can constant-folded as
1775 PERL_STATIC_INLINE OP*
1776 S_padhv_rv2hv_common(pTHX_ HV *hv, U8 gimme, bool is_keys, bool has_targ)
1785 assert(PL_op->op_type == OP_PADHV || PL_op->op_type == OP_RV2HV);
1787 if (gimme == G_ARRAY) {
1793 /* 'keys %h' masquerading as '%h': reset iterator */
1794 (void)hv_iterinit(hv);
1796 if (gimme == G_VOID)
1799 is_bool = ( PL_op->op_private & OPpTRUEBOOL
1800 || ( PL_op->op_private & OPpMAYBE_TRUEBOOL
1801 && block_gimme() == G_VOID));
1802 is_tied = SvRMAGICAL(hv) && (mg = mg_find(MUTABLE_SV(hv), PERL_MAGIC_tied));
1804 if (UNLIKELY(is_tied)) {
1805 if (is_keys && !is_bool) {
1807 while (hv_iternext(hv))
1812 sv = magic_scalarpack(hv, mg);
1819 sv = i ? &PL_sv_yes : &PL_sv_zero;
1831 /* parent op should be an unused OP_KEYS whose targ we can
1836 assert(!OpHAS_SIBLING(PL_op));
1837 k = PL_op->op_sibparent;
1838 assert(k->op_type == OP_KEYS);
1839 TARG = PAD_SV(k->op_targ);
1852 /* This is also called directly by pp_lvavref. */
1857 assert(SvTYPE(TARG) == SVt_PVAV);
1858 if (UNLIKELY( PL_op->op_private & OPpLVAL_INTRO ))
1859 if (LIKELY( !(PL_op->op_private & OPpPAD_STATE) ))
1860 SAVECLEARSV(PAD_SVl(PL_op->op_targ));
1863 if (PL_op->op_flags & OPf_REF) {
1867 else if (PL_op->op_private & OPpMAYBE_LVSUB) {
1868 const I32 flags = is_lvalue_sub();
1869 if (flags && !(flags & OPpENTERSUB_INARGS)) {
1870 if (GIMME_V == G_SCALAR)
1871 /* diag_listed_as: Can't return %s to lvalue scalar context */
1872 Perl_croak(aTHX_ "Can't return array to lvalue scalar context");
1879 if (gimme == G_ARRAY)
1880 return S_pushav(aTHX_ (AV*)TARG);
1882 if (gimme == G_SCALAR) {
1883 const SSize_t maxarg = AvFILL(MUTABLE_AV(TARG)) + 1;
1886 else if (PL_op->op_private & OPpTRUEBOOL)
1900 assert(SvTYPE(TARG) == SVt_PVHV);
1901 if (UNLIKELY( PL_op->op_private & OPpLVAL_INTRO ))
1902 if (LIKELY( !(PL_op->op_private & OPpPAD_STATE) ))
1903 SAVECLEARSV(PAD_SVl(PL_op->op_targ));
1907 if (PL_op->op_flags & OPf_REF) {
1911 else if (PL_op->op_private & OPpMAYBE_LVSUB) {
1912 const I32 flags = is_lvalue_sub();
1913 if (flags && !(flags & OPpENTERSUB_INARGS)) {
1914 if (GIMME_V == G_SCALAR)
1915 /* diag_listed_as: Can't return %s to lvalue scalar context */
1916 Perl_croak(aTHX_ "Can't return hash to lvalue scalar context");
1924 return S_padhv_rv2hv_common(aTHX_ (HV*)TARG, gimme,
1925 cBOOL(PL_op->op_private & OPpPADHV_ISKEYS),
1930 /* also used for: pp_rv2hv() */
1931 /* also called directly by pp_lvavref */
1936 const U8 gimme = GIMME_V;
1937 static const char an_array[] = "an ARRAY";
1938 static const char a_hash[] = "a HASH";
1939 const bool is_pp_rv2av = PL_op->op_type == OP_RV2AV
1940 || PL_op->op_type == OP_LVAVREF;
1941 const svtype type = is_pp_rv2av ? SVt_PVAV : SVt_PVHV;
1945 if (UNLIKELY(SvAMAGIC(sv))) {
1946 sv = amagic_deref_call(sv, is_pp_rv2av ? to_av_amg : to_hv_amg);
1949 if (UNLIKELY(SvTYPE(sv) != type))
1950 /* diag_listed_as: Not an ARRAY reference */
1951 DIE(aTHX_ "Not %s reference", is_pp_rv2av ? an_array : a_hash);
1952 else if (UNLIKELY(PL_op->op_flags & OPf_MOD
1953 && PL_op->op_private & OPpLVAL_INTRO))
1954 Perl_croak(aTHX_ "%s", PL_no_localize_ref);
1956 else if (UNLIKELY(SvTYPE(sv) != type)) {
1959 if (!isGV_with_GP(sv)) {
1960 gv = Perl_softref2xv(aTHX_ sv, is_pp_rv2av ? an_array : a_hash,
1966 gv = MUTABLE_GV(sv);
1968 sv = is_pp_rv2av ? MUTABLE_SV(GvAVn(gv)) : MUTABLE_SV(GvHVn(gv));
1969 if (PL_op->op_private & OPpLVAL_INTRO)
1970 sv = is_pp_rv2av ? MUTABLE_SV(save_ary(gv)) : MUTABLE_SV(save_hash(gv));
1972 if (PL_op->op_flags & OPf_REF) {
1976 else if (UNLIKELY(PL_op->op_private & OPpMAYBE_LVSUB)) {
1977 const I32 flags = is_lvalue_sub();
1978 if (flags && !(flags & OPpENTERSUB_INARGS)) {
1979 if (gimme != G_ARRAY)
1980 goto croak_cant_return;
1987 AV *const av = MUTABLE_AV(sv);
1989 if (gimme == G_ARRAY) {
1992 return S_pushav(aTHX_ av);
1995 if (gimme == G_SCALAR) {
1996 const SSize_t maxarg = AvFILL(av) + 1;
1997 if (PL_op->op_private & OPpTRUEBOOL)
1998 SETs(maxarg ? &PL_sv_yes : &PL_sv_zero);
2007 return S_padhv_rv2hv_common(aTHX_ (HV*)sv, gimme,
2008 cBOOL(PL_op->op_private & OPpRV2HV_ISKEYS),
2014 Perl_croak(aTHX_ "Can't return %s to lvalue scalar context",
2015 is_pp_rv2av ? "array" : "hash");
2020 S_do_oddball(pTHX_ SV **oddkey, SV **firstkey)
2022 PERL_ARGS_ASSERT_DO_ODDBALL;
2025 if (ckWARN(WARN_MISC)) {
2027 if (oddkey == firstkey &&
2029 (SvTYPE(SvRV(*oddkey)) == SVt_PVAV ||
2030 SvTYPE(SvRV(*oddkey)) == SVt_PVHV))
2032 err = "Reference found where even-sized list expected";
2035 err = "Odd number of elements in hash assignment";
2036 Perl_warner(aTHX_ packWARN(WARN_MISC), "%s", err);
2043 /* Do a mark and sweep with the SVf_BREAK flag to detect elements which
2044 * are common to both the LHS and RHS of an aassign, and replace them
2045 * with copies. All these copies are made before the actual list assign is
2048 * For example in ($a,$b) = ($b,$a), assigning the value of the first RHS
2049 * element ($b) to the first LH element ($a), modifies $a; when the
2050 * second assignment is done, the second RH element now has the wrong
2051 * value. So we initially replace the RHS with ($b, mortalcopy($a)).
2052 * Note that we don't need to make a mortal copy of $b.
2054 * The algorithm below works by, for every RHS element, mark the
2055 * corresponding LHS target element with SVf_BREAK. Then if the RHS
2056 * element is found with SVf_BREAK set, it means it would have been
2057 * modified, so make a copy.
2058 * Note that by scanning both LHS and RHS in lockstep, we avoid
2059 * unnecessary copies (like $b above) compared with a naive
2060 * "mark all LHS; copy all marked RHS; unmark all LHS".
2062 * If the LHS element is a 'my' declaration' and has a refcount of 1, then
2063 * it can't be common and can be skipped.
2065 * On DEBUGGING builds it takes an extra boolean, fake. If true, it means
2066 * that we thought we didn't need to call S_aassign_copy_common(), but we
2067 * have anyway for sanity checking. If we find we need to copy, then panic.
2070 PERL_STATIC_INLINE void
2071 S_aassign_copy_common(pTHX_ SV **firstlelem, SV **lastlelem,
2072 SV **firstrelem, SV **lastrelem
2081 SSize_t lcount = lastlelem - firstlelem + 1;
2082 bool marked = FALSE; /* have we marked any LHS with SVf_BREAK ? */
2083 bool const do_rc1 = cBOOL(PL_op->op_private & OPpASSIGN_COMMON_RC1);
2084 bool copy_all = FALSE;
2086 assert(!PL_in_clean_all); /* SVf_BREAK not already in use */
2087 assert(firstlelem < lastlelem); /* at least 2 LH elements */
2088 assert(firstrelem < lastrelem); /* at least 2 RH elements */
2092 /* we never have to copy the first RH element; it can't be corrupted
2093 * by assigning something to the corresponding first LH element.
2094 * So this scan does in a loop: mark LHS[N]; test RHS[N+1]
2096 relem = firstrelem + 1;
2098 for (; relem <= lastrelem; relem++) {
2101 /* mark next LH element */
2103 if (--lcount >= 0) {
2106 if (UNLIKELY(!svl)) {/* skip AV alias marker */
2107 assert (lelem <= lastlelem);
2113 if (SvSMAGICAL(svl)) {
2116 if (SvTYPE(svl) == SVt_PVAV || SvTYPE(svl) == SVt_PVHV) {
2119 /* this LH element will consume all further args;
2120 * no need to mark any further LH elements (if any).
2121 * But we still need to scan any remaining RHS elements;
2122 * set lcount negative to distinguish from lcount == 0,
2123 * so the loop condition continues being true
2126 lelem--; /* no need to unmark this element */
2128 else if (!(do_rc1 && SvREFCNT(svl) == 1) && !SvIMMORTAL(svl)) {
2129 SvFLAGS(svl) |= SVf_BREAK;
2133 /* don't check RH element if no SVf_BREAK flags set yet */
2140 /* see if corresponding RH element needs copying */
2146 if (UNLIKELY(SvFLAGS(svr) & (SVf_BREAK|SVs_GMG) || copy_all)) {
2147 U32 brk = (SvFLAGS(svr) & SVf_BREAK);
2151 /* op_dump(PL_op); */
2153 "panic: aassign skipped needed copy of common RH elem %"
2154 UVuf, (UV)(relem - firstrelem));
2158 TAINT_NOT; /* Each item is independent */
2160 /* Dear TODO test in t/op/sort.t, I love you.
2161 (It's relying on a panic, not a "semi-panic" from newSVsv()
2162 and then an assertion failure below.) */
2163 if (UNLIKELY(SvIS_FREED(svr))) {
2164 Perl_croak(aTHX_ "panic: attempt to copy freed scalar %p",
2167 /* avoid break flag while copying; otherwise COW etc
2169 SvFLAGS(svr) &= ~SVf_BREAK;
2170 /* Not newSVsv(), as it does not allow copy-on-write,
2171 resulting in wasteful copies.
2172 Also, we use SV_NOSTEAL in case the SV is used more than
2173 once, e.g. (...) = (f())[0,0]
2174 Where the same SV appears twice on the RHS without a ref
2175 count bump. (Although I suspect that the SV won't be
2176 stealable here anyway - DAPM).
2178 *relem = sv_mortalcopy_flags(svr,
2179 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
2180 /* ... but restore afterwards in case it's needed again,
2181 * e.g. ($a,$b,$c) = (1,$a,$a)
2183 SvFLAGS(svr) |= brk;
2195 while (lelem > firstlelem) {
2196 SV * const svl = *(--lelem);
2198 SvFLAGS(svl) &= ~SVf_BREAK;
2207 SV **lastlelem = PL_stack_sp;
2208 SV **lastrelem = PL_stack_base + POPMARK;
2209 SV **firstrelem = PL_stack_base + POPMARK + 1;
2210 SV **firstlelem = lastrelem + 1;
2215 /* PL_delaymagic is restored by JUMPENV_POP on dieing, so we
2216 * only need to save locally, not on the save stack */
2217 U16 old_delaymagic = PL_delaymagic;
2222 PL_delaymagic = DM_DELAY; /* catch simultaneous items */
2224 /* If there's a common identifier on both sides we have to take
2225 * special care that assigning the identifier on the left doesn't
2226 * clobber a value on the right that's used later in the list.
2229 /* at least 2 LH and RH elements, or commonality isn't an issue */
2230 if (firstlelem < lastlelem && firstrelem < lastrelem) {
2231 for (relem = firstrelem+1; relem <= lastrelem; relem++) {
2232 if (SvGMAGICAL(*relem))
2235 for (lelem = firstlelem; lelem <= lastlelem; lelem++) {
2236 if (*lelem && SvSMAGICAL(*lelem))
2239 if ( PL_op->op_private & (OPpASSIGN_COMMON_SCALAR|OPpASSIGN_COMMON_RC1) ) {
2240 if (PL_op->op_private & OPpASSIGN_COMMON_RC1) {
2241 /* skip the scan if all scalars have a ref count of 1 */
2242 for (lelem = firstlelem; lelem <= lastlelem; lelem++) {
2244 if (!sv || SvREFCNT(sv) == 1)
2246 if (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVAV)
2253 S_aassign_copy_common(aTHX_
2254 firstlelem, lastlelem, firstrelem, lastrelem
2264 /* on debugging builds, do the scan even if we've concluded we
2265 * don't need to, then panic if we find commonality. Note that the
2266 * scanner assumes at least 2 elements */
2267 if (firstlelem < lastlelem && firstrelem < lastrelem) {
2278 if (relem > lastrelem)
2281 /* first lelem loop while there are still relems */
2282 while (LIKELY(lelem <= lastlelem)) {
2286 TAINT_NOT; /* Each item stands on its own, taintwise. */
2288 assert(relem <= lastrelem);
2289 if (UNLIKELY(!lsv)) {
2292 ASSUME(SvTYPE(lsv) == SVt_PVAV);
2295 switch (SvTYPE(lsv)) {
2300 SSize_t nelems = lastrelem - relem + 1;
2301 AV *ary = MUTABLE_AV(lsv);
2303 /* Assigning to an aggregate is tricky. First there is the
2304 * issue of commonality, e.g. @a = ($a[0]). Since the
2305 * stack isn't refcounted, clearing @a prior to storing
2306 * elements will free $a[0]. Similarly with
2307 * sub FETCH { $status[$_[1]] } @status = @tied[0,1];
2309 * The way to avoid these issues is to make the copy of each
2310 * SV (and we normally store a *copy* in the array) *before*
2311 * clearing the array. But this has a problem in that
2312 * if the code croaks during copying, the not-yet-stored copies
2313 * could leak. One way to avoid this is to make all the copies
2314 * mortal, but that's quite expensive.
2316 * The current solution to these issues is to use a chunk
2317 * of the tmps stack as a temporary refcounted-stack. SVs
2318 * will be put on there during processing to avoid leaks,
2319 * but will be removed again before the end of this block,
2320 * so free_tmps() is never normally called. Also, the
2321 * sv_refcnt of the SVs doesn't have to be manipulated, since
2322 * the ownership of 1 reference count is transferred directly
2323 * from the tmps stack to the AV when the SV is stored.
2325 * We disarm slots in the temps stack by storing PL_sv_undef
2326 * there: it doesn't matter if that SV's refcount is
2327 * repeatedly decremented during a croak. But usually this is
2328 * only an interim measure. By the end of this code block
2329 * we try where possible to not leave any PL_sv_undef's on the
2330 * tmps stack e.g. by shuffling newer entries down.
2332 * There is one case where we don't copy: non-magical
2333 * SvTEMP(sv)'s with a ref count of 1. The only owner of these
2334 * is on the tmps stack, so its safe to directly steal the SV
2335 * rather than copying. This is common in things like function
2336 * returns, map etc, which all return a list of such SVs.
2338 * Note however something like @a = (f())[0,0], where there is
2339 * a danger of the same SV being shared: this avoided because
2340 * when the SV is stored as $a[0], its ref count gets bumped,
2341 * so the RC==1 test fails and the second element is copied
2344 * We also use one slot in the tmps stack to hold an extra
2345 * ref to the array, to ensure it doesn't get prematurely
2346 * freed. Again, this is removed before the end of this block.
2348 * Note that OPpASSIGN_COMMON_AGG is used to flag a possible
2349 * @a = ($a[0]) case, but the current implementation uses the
2350 * same algorithm regardless, so ignores that flag. (It *is*
2351 * used in the hash branch below, however).
2354 /* Reserve slots for ary, plus the elems we're about to copy,
2355 * then protect ary and temporarily void the remaining slots
2356 * with &PL_sv_undef */
2357 EXTEND_MORTAL(nelems + 1);
2358 PL_tmps_stack[++PL_tmps_ix] = SvREFCNT_inc_simple_NN(ary);
2359 tmps_base = PL_tmps_ix + 1;
2360 for (i = 0; i < nelems; i++)
2361 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
2362 PL_tmps_ix += nelems;
2364 /* Make a copy of each RHS elem and save on the tmps_stack
2365 * (or pass through where we can optimise away the copy) */
2367 if (UNLIKELY(alias)) {
2368 U32 lval = (gimme == G_ARRAY)
2369 ? (PL_op->op_flags & OPf_MOD || LVRET) : 0;
2370 for (svp = relem; svp <= lastrelem; svp++) {
2375 DIE(aTHX_ "Assigned value is not a reference");
2376 if (SvTYPE(SvRV(rsv)) > SVt_PVLV)
2377 /* diag_listed_as: Assigned value is not %s reference */
2379 "Assigned value is not a SCALAR reference");
2381 *svp = rsv = sv_mortalcopy(rsv);
2382 /* XXX else check for weak refs? */
2383 rsv = SvREFCNT_inc_NN(SvRV(rsv));
2384 assert(tmps_base <= PL_tmps_max);
2385 PL_tmps_stack[tmps_base++] = rsv;
2389 for (svp = relem; svp <= lastrelem; svp++) {
2392 if (SvTEMP(rsv) && !SvGMAGICAL(rsv) && SvREFCNT(rsv) == 1) {
2393 /* can skip the copy */
2394 SvREFCNT_inc_simple_void_NN(rsv);
2399 /* do get before newSV, in case it dies and leaks */
2402 /* see comment in S_aassign_copy_common about
2404 sv_setsv_flags(nsv, rsv,
2405 (SV_DO_COW_SVSETSV|SV_NOSTEAL));
2409 assert(tmps_base <= PL_tmps_max);
2410 PL_tmps_stack[tmps_base++] = rsv;
2414 if (SvRMAGICAL(ary) || AvFILLp(ary) >= 0) /* may be non-empty */
2417 /* store in the array, the SVs that are in the tmps stack */
2419 tmps_base -= nelems;
2421 if (SvMAGICAL(ary) || SvREADONLY(ary) || !AvREAL(ary)) {
2422 /* for arrays we can't cheat with, use the official API */
2423 av_extend(ary, nelems - 1);
2424 for (i = 0; i < nelems; i++) {
2425 SV **svp = &(PL_tmps_stack[tmps_base + i]);
2427 /* A tied store won't take ownership of rsv, so keep
2428 * the 1 refcnt on the tmps stack; otherwise disarm
2429 * the tmps stack entry */
2430 if (av_store(ary, i, rsv))
2431 *svp = &PL_sv_undef;
2432 /* av_store() may have added set magic to rsv */;
2435 /* disarm ary refcount: see comments below about leak */
2436 PL_tmps_stack[tmps_base - 1] = &PL_sv_undef;
2439 /* directly access/set the guts of the AV */
2440 SSize_t fill = nelems - 1;
2441 if (fill > AvMAX(ary))
2442 av_extend_guts(ary, fill, &AvMAX(ary), &AvALLOC(ary),
2444 AvFILLp(ary) = fill;
2445 Copy(&(PL_tmps_stack[tmps_base]), AvARRAY(ary), nelems, SV*);
2446 /* Quietly remove all the SVs from the tmps stack slots,
2447 * since ary has now taken ownership of the refcnt.
2448 * Also remove ary: which will now leak if we die before
2449 * the SvREFCNT_dec_NN(ary) below */
2450 if (UNLIKELY(PL_tmps_ix >= tmps_base + nelems))
2451 Move(&PL_tmps_stack[tmps_base + nelems],
2452 &PL_tmps_stack[tmps_base - 1],
2453 PL_tmps_ix - (tmps_base + nelems) + 1,
2455 PL_tmps_ix -= (nelems + 1);
2458 if (UNLIKELY(PL_delaymagic & DM_ARRAY_ISA))
2459 /* its assumed @ISA set magic can't die and leak ary */
2460 SvSETMAGIC(MUTABLE_SV(ary));
2461 SvREFCNT_dec_NN(ary);
2463 relem = lastrelem + 1;
2467 case SVt_PVHV: { /* normal hash */
2473 SSize_t nelems = lastrelem - relem + 1;
2474 HV *hash = MUTABLE_HV(lsv);
2476 if (UNLIKELY(nelems & 1)) {
2477 do_oddball(lastrelem, relem);
2478 /* we have firstlelem to reuse, it's not needed any more */
2479 *++lastrelem = &PL_sv_undef;
2483 /* See the SVt_PVAV branch above for a long description of
2484 * how the following all works. The main difference for hashes
2485 * is that we treat keys and values separately (and have
2486 * separate loops for them): as for arrays, values are always
2487 * copied (except for the SvTEMP optimisation), since they
2488 * need to be stored in the hash; while keys are only
2489 * processed where they might get prematurely freed or
2492 /* tmps stack slots:
2493 * * reserve a slot for the hash keepalive;
2494 * * reserve slots for the hash values we're about to copy;
2495 * * preallocate for the keys we'll possibly copy or refcount bump
2497 * then protect hash and temporarily void the remaining
2498 * value slots with &PL_sv_undef */
2499 EXTEND_MORTAL(nelems + 1);
2501 /* convert to number of key/value pairs */
2504 PL_tmps_stack[++PL_tmps_ix] = SvREFCNT_inc_simple_NN(hash);
2505 tmps_base = PL_tmps_ix + 1;
2506 for (i = 0; i < nelems; i++)
2507 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
2508 PL_tmps_ix += nelems;
2510 /* Make a copy of each RHS hash value and save on the tmps_stack
2511 * (or pass through where we can optimise away the copy) */
2513 for (svp = relem + 1; svp <= lastrelem; svp += 2) {
2516 if (SvTEMP(rsv) && !SvGMAGICAL(rsv) && SvREFCNT(rsv) == 1) {
2517 /* can skip the copy */
2518 SvREFCNT_inc_simple_void_NN(rsv);
2523 /* do get before newSV, in case it dies and leaks */
2526 /* see comment in S_aassign_copy_common about
2528 sv_setsv_flags(nsv, rsv,
2529 (SV_DO_COW_SVSETSV|SV_NOSTEAL));
2533 assert(tmps_base <= PL_tmps_max);
2534 PL_tmps_stack[tmps_base++] = rsv;
2536 tmps_base -= nelems;
2539 /* possibly protect keys */
2541 if (UNLIKELY(gimme == G_ARRAY)) {
2543 * @a = ((%h = ($$r, 1)), $r = "x");
2544 * $_++ for %h = (1,2,3,4);
2546 EXTEND_MORTAL(nelems);
2547 for (svp = relem; svp <= lastrelem; svp += 2)
2548 *svp = sv_mortalcopy_flags(*svp,
2549 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
2551 else if (PL_op->op_private & OPpASSIGN_COMMON_AGG) {
2552 /* for possible commonality, e.g.
2554 * avoid premature freeing RHS keys by mortalising
2556 * For a magic element, make a copy so that its magic is
2557 * called *before* the hash is emptied (which may affect
2558 * a tied value for example).
2559 * In theory we should check for magic keys in all
2560 * cases, not just under OPpASSIGN_COMMON_AGG, but in
2561 * practice, !OPpASSIGN_COMMON_AGG implies only
2562 * constants or padtmps on the RHS.
2564 EXTEND_MORTAL(nelems);
2565 for (svp = relem; svp <= lastrelem; svp += 2) {
2567 if (UNLIKELY(SvGMAGICAL(rsv))) {
2569 *svp = sv_mortalcopy_flags(*svp,
2570 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
2571 /* allow other branch to continue pushing
2572 * onto tmps stack without checking each time */
2573 n = (lastrelem - relem) >> 1;
2577 PL_tmps_stack[++PL_tmps_ix] =
2578 SvREFCNT_inc_simple_NN(rsv);
2582 if (SvRMAGICAL(hash) || HvUSEDKEYS(hash))
2585 /* now assign the keys and values to the hash */
2589 if (UNLIKELY(gimme == G_ARRAY)) {
2590 /* @a = (%h = (...)) etc */
2592 SV **topelem = relem;
2594 for (i = 0, svp = relem; svp <= lastrelem; i++, svp++) {
2597 /* remove duplicates from list we return */
2598 if (!hv_exists_ent(hash, key, 0)) {
2599 /* copy key back: possibly to an earlier
2600 * stack location if we encountered dups earlier,
2601 * The values will be updated later
2606 /* A tied store won't take ownership of val, so keep
2607 * the 1 refcnt on the tmps stack; otherwise disarm
2608 * the tmps stack entry */
2609 if (hv_store_ent(hash, key, val, 0))
2610 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
2613 /* hv_store_ent() may have added set magic to val */;
2616 if (topelem < svp) {
2617 /* at this point we have removed the duplicate key/value
2618 * pairs from the stack, but the remaining values may be
2619 * wrong; i.e. with (a 1 a 2 b 3) on the stack we've removed
2620 * the (a 2), but the stack now probably contains
2621 * (a <freed> b 3), because { hv_save(a,1); hv_save(a,2) }
2622 * obliterates the earlier key. So refresh all values. */
2623 lastrelem = topelem - 1;
2624 while (relem < lastrelem) {
2626 he = hv_fetch_ent(hash, *relem++, 0, 0);
2627 *relem++ = (he ? HeVAL(he) : &PL_sv_undef);
2633 for (i = 0, svp = relem; svp <= lastrelem; i++, svp++) {
2636 if (hv_store_ent(hash, key, val, 0))
2637 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
2640 /* hv_store_ent() may have added set magic to val */;
2646 /* there are still some 'live' recounts on the tmps stack
2647 * - usually caused by storing into a tied hash. So let
2648 * free_tmps() do the proper but slow job later.
2649 * Just disarm hash refcount: see comments below about leak
2651 PL_tmps_stack[tmps_base - 1] = &PL_sv_undef;
2654 /* Quietly remove all the SVs from the tmps stack slots,
2655 * since hash has now taken ownership of the refcnt.
2656 * Also remove hash: which will now leak if we die before
2657 * the SvREFCNT_dec_NN(hash) below */
2658 if (UNLIKELY(PL_tmps_ix >= tmps_base + nelems))
2659 Move(&PL_tmps_stack[tmps_base + nelems],
2660 &PL_tmps_stack[tmps_base - 1],
2661 PL_tmps_ix - (tmps_base + nelems) + 1,
2663 PL_tmps_ix -= (nelems + 1);
2666 SvREFCNT_dec_NN(hash);
2668 relem = lastrelem + 1;
2673 if (!SvIMMORTAL(lsv)) {
2677 SvTEMP(lsv) && !SvSMAGICAL(lsv) && SvREFCNT(lsv) == 1 &&
2678 (!isGV_with_GP(lsv) || SvFAKE(lsv)) && ckWARN(WARN_MISC)
2681 packWARN(WARN_MISC),
2682 "Useless assignment to a temporary"
2685 /* avoid freeing $$lsv if it might be needed for further
2686 * elements, e.g. ($ref, $foo) = (1, $$ref) */
2688 && ( ((ref = SvRV(lsv)), SvREFCNT(ref)) == 1)
2689 && lelem <= lastlelem
2692 SvREFCNT_inc_simple_void_NN(ref);
2693 /* an unrolled sv_2mortal */
2695 if (UNLIKELY(ix >= PL_tmps_max))
2696 /* speculatively grow enough to cover other
2698 (void)tmps_grow_p(ix + (lastlelem - lelem));
2699 PL_tmps_stack[ix] = ref;
2702 sv_setsv(lsv, *relem);
2706 if (++relem > lastrelem)
2715 /* simplified lelem loop for when there are no relems left */
2716 while (LIKELY(lelem <= lastlelem)) {
2719 TAINT_NOT; /* Each item stands on its own, taintwise. */
2721 if (UNLIKELY(!lsv)) {
2723 ASSUME(SvTYPE(lsv) == SVt_PVAV);
2726 switch (SvTYPE(lsv)) {
2728 if (SvRMAGICAL(lsv) || AvFILLp((SV*)lsv) >= 0) {
2730 if (UNLIKELY(PL_delaymagic & DM_ARRAY_ISA))
2736 if (SvRMAGICAL(lsv) || HvUSEDKEYS((HV*)lsv))
2741 if (!SvIMMORTAL(lsv)) {
2750 TAINT_NOT; /* result of list assign isn't tainted */
2752 if (UNLIKELY(PL_delaymagic & ~DM_DELAY)) {
2753 /* Will be used to set PL_tainting below */
2754 Uid_t tmp_uid = PerlProc_getuid();
2755 Uid_t tmp_euid = PerlProc_geteuid();
2756 Gid_t tmp_gid = PerlProc_getgid();
2757 Gid_t tmp_egid = PerlProc_getegid();
2759 /* XXX $> et al currently silently ignore failures */
2760 if (PL_delaymagic & DM_UID) {
2761 #ifdef HAS_SETRESUID
2763 setresuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
2764 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1,
2766 #elif defined(HAS_SETREUID)
2768 setreuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
2769 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1));
2772 if ((PL_delaymagic & DM_UID) == DM_RUID) {
2773 PERL_UNUSED_RESULT(setruid(PL_delaymagic_uid));
2774 PL_delaymagic &= ~DM_RUID;
2776 # endif /* HAS_SETRUID */
2778 if ((PL_delaymagic & DM_UID) == DM_EUID) {
2779 PERL_UNUSED_RESULT(seteuid(PL_delaymagic_euid));
2780 PL_delaymagic &= ~DM_EUID;
2782 # endif /* HAS_SETEUID */
2783 if (PL_delaymagic & DM_UID) {
2784 if (PL_delaymagic_uid != PL_delaymagic_euid)
2785 DIE(aTHX_ "No setreuid available");
2786 PERL_UNUSED_RESULT(PerlProc_setuid(PL_delaymagic_uid));
2788 #endif /* HAS_SETRESUID */
2790 tmp_uid = PerlProc_getuid();
2791 tmp_euid = PerlProc_geteuid();
2793 /* XXX $> et al currently silently ignore failures */
2794 if (PL_delaymagic & DM_GID) {
2795 #ifdef HAS_SETRESGID
2797 setresgid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
2798 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1,
2800 #elif defined(HAS_SETREGID)
2802 setregid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
2803 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1));
2806 if ((PL_delaymagic & DM_GID) == DM_RGID) {
2807 PERL_UNUSED_RESULT(setrgid(PL_delaymagic_gid));
2808 PL_delaymagic &= ~DM_RGID;
2810 # endif /* HAS_SETRGID */
2812 if ((PL_delaymagic & DM_GID) == DM_EGID) {
2813 PERL_UNUSED_RESULT(setegid(PL_delaymagic_egid));
2814 PL_delaymagic &= ~DM_EGID;
2816 # endif /* HAS_SETEGID */
2817 if (PL_delaymagic & DM_GID) {
2818 if (PL_delaymagic_gid != PL_delaymagic_egid)
2819 DIE(aTHX_ "No setregid available");
2820 PERL_UNUSED_RESULT(PerlProc_setgid(PL_delaymagic_gid));
2822 #endif /* HAS_SETRESGID */
2824 tmp_gid = PerlProc_getgid();
2825 tmp_egid = PerlProc_getegid();
2827 TAINTING_set( TAINTING_get | (tmp_uid && (tmp_euid != tmp_uid || tmp_egid != tmp_gid)) );
2828 #ifdef NO_TAINT_SUPPORT
2829 PERL_UNUSED_VAR(tmp_uid);
2830 PERL_UNUSED_VAR(tmp_euid);
2831 PERL_UNUSED_VAR(tmp_gid);
2832 PERL_UNUSED_VAR(tmp_egid);
2835 PL_delaymagic = old_delaymagic;
2837 if (gimme == G_VOID)
2838 SP = firstrelem - 1;
2839 else if (gimme == G_SCALAR) {
2842 if (PL_op->op_private & OPpASSIGN_TRUEBOOL)
2843 SETs((firstlelem - firstrelem) ? &PL_sv_yes : &PL_sv_zero);
2846 SETi(firstlelem - firstrelem);
2858 PMOP * const pm = cPMOP;
2859 REGEXP * rx = PM_GETRE(pm);
2860 regexp *prog = ReANY(rx);
2861 SV * const pkg = RXp_ENGINE(prog)->qr_package(aTHX_ (rx));
2862 SV * const rv = sv_newmortal();
2866 SvUPGRADE(rv, SVt_IV);
2867 /* For a subroutine describing itself as "This is a hacky workaround" I'm
2868 loathe to use it here, but it seems to be the right fix. Or close.
2869 The key part appears to be that it's essential for pp_qr to return a new
2870 object (SV), which implies that there needs to be an effective way to
2871 generate a new SV from the existing SV that is pre-compiled in the
2873 SvRV_set(rv, MUTABLE_SV(reg_temp_copy(NULL, rx)));
2876 cvp = &( ReANY((REGEXP *)SvRV(rv))->qr_anoncv);
2877 if (UNLIKELY((cv = *cvp) && CvCLONE(*cvp))) {
2878 *cvp = cv_clone(cv);
2879 SvREFCNT_dec_NN(cv);
2883 HV *const stash = gv_stashsv(pkg, GV_ADD);
2884 SvREFCNT_dec_NN(pkg);
2885 (void)sv_bless(rv, stash);
2888 if (UNLIKELY(RXp_ISTAINTED(prog))) {
2890 SvTAINTED_on(SvRV(rv));
2903 SSize_t curpos = 0; /* initial pos() or current $+[0] */
2906 const char *truebase; /* Start of string */
2907 REGEXP *rx = PM_GETRE(pm);
2908 regexp *prog = ReANY(rx);
2910 const U8 gimme = GIMME_V;
2912 const I32 oldsave = PL_savestack_ix;
2913 I32 had_zerolen = 0;
2916 if (PL_op->op_flags & OPf_STACKED)
2927 PUTBACK; /* EVAL blocks need stack_sp. */
2928 /* Skip get-magic if this is a qr// clone, because regcomp has
2930 truebase = prog->mother_re
2931 ? SvPV_nomg_const(TARG, len)
2932 : SvPV_const(TARG, len);
2934 DIE(aTHX_ "panic: pp_match");
2935 strend = truebase + len;
2936 rxtainted = (RXp_ISTAINTED(prog) ||
2937 (TAINT_get && (pm->op_pmflags & PMf_RETAINT)));
2940 /* We need to know this in case we fail out early - pos() must be reset */
2941 global = dynpm->op_pmflags & PMf_GLOBAL;
2943 /* PMdf_USED is set after a ?? matches once */
2946 SvREADONLY(PL_regex_pad[pm->op_pmoffset])
2948 pm->op_pmflags & PMf_USED
2951 DEBUG_r(PerlIO_printf(Perl_debug_log, "?? already matched once"));
2955 /* handle the empty pattern */
2956 if (!RX_PRELEN(rx) && PL_curpm && !prog->mother_re) {
2957 if (PL_curpm == PL_reg_curpm) {
2958 if (PL_curpm_under) {
2959 if (PL_curpm_under == PL_reg_curpm) {
2960 Perl_croak(aTHX_ "Infinite recursion via empty pattern");
2962 pm = PL_curpm_under;
2972 if (RXp_MINLEN(prog) >= 0 && (STRLEN)RXp_MINLEN(prog) > len) {
2973 DEBUG_r(PerlIO_printf(Perl_debug_log, "String shorter than min possible regex match (%"
2974 UVuf " < %" IVdf ")\n",
2975 (UV)len, (IV)RXp_MINLEN(prog)));
2979 /* get pos() if //g */
2981 mg = mg_find_mglob(TARG);
2982 if (mg && mg->mg_len >= 0) {
2983 curpos = MgBYTEPOS(mg, TARG, truebase, len);
2984 /* last time pos() was set, it was zero-length match */
2985 if (mg->mg_flags & MGf_MINMATCH)
2990 #ifdef PERL_SAWAMPERSAND
2991 if ( RXp_NPARENS(prog)
2993 || (RXp_EXTFLAGS(prog) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
2994 || (dynpm->op_pmflags & PMf_KEEPCOPY)
2998 r_flags |= (REXEC_COPY_STR|REXEC_COPY_SKIP_PRE);
2999 /* in @a =~ /(.)/g, we iterate multiple times, but copy the buffer
3000 * only on the first iteration. Therefore we need to copy $' as well
3001 * as $&, to make the rest of the string available for captures in
3002 * subsequent iterations */
3003 if (! (global && gimme == G_ARRAY))
3004 r_flags |= REXEC_COPY_SKIP_POST;
3006 #ifdef PERL_SAWAMPERSAND
3007 if (dynpm->op_pmflags & PMf_KEEPCOPY)
3008 /* handle KEEPCOPY in pmop but not rx, eg $r=qr/a/; /$r/p */
3009 r_flags &= ~(REXEC_COPY_SKIP_PRE|REXEC_COPY_SKIP_POST);
3016 s = truebase + curpos;
3018 if (!CALLREGEXEC(rx, (char*)s, (char *)strend, (char*)truebase,
3019 had_zerolen, TARG, NULL, r_flags))
3023 if (dynpm->op_pmflags & PMf_ONCE)
3025 SvREADONLY_on(PL_regex_pad[dynpm->op_pmoffset]);
3027 dynpm->op_pmflags |= PMf_USED;
3031 RXp_MATCH_TAINTED_on(prog);
3032 TAINT_IF(RXp_MATCH_TAINTED(prog));
3036 if (global && (gimme != G_ARRAY || (dynpm->op_pmflags & PMf_CONTINUE))) {
3038 mg = sv_magicext_mglob(TARG);
3039 MgBYTEPOS_set(mg, TARG, truebase, RXp_OFFS(prog)[0].end);
3040 if (RXp_ZERO_LEN(prog))
3041 mg->mg_flags |= MGf_MINMATCH;
3043 mg->mg_flags &= ~MGf_MINMATCH;
3046 if ((!RXp_NPARENS(prog) && !global) || gimme != G_ARRAY) {
3047 LEAVE_SCOPE(oldsave);
3051 /* push captures on stack */
3054 const I32 nparens = RXp_NPARENS(prog);
3055 I32 i = (global && !nparens) ? 1 : 0;
3057 SPAGAIN; /* EVAL blocks could move the stack. */
3058 EXTEND(SP, nparens + i);
3059 EXTEND_MORTAL(nparens + i);
3060 for (i = !i; i <= nparens; i++) {
3061 PUSHs(sv_newmortal());
3062 if (LIKELY((RXp_OFFS(prog)[i].start != -1)
3063 && RXp_OFFS(prog)[i].end != -1 ))
3065 const I32 len = RXp_OFFS(prog)[i].end - RXp_OFFS(prog)[i].start;
3066 const char * const s = RXp_OFFS(prog)[i].start + truebase;
3067 if (UNLIKELY( RXp_OFFS(prog)[i].end < 0
3068 || RXp_OFFS(prog)[i].start < 0
3070 || len > strend - s)
3072 DIE(aTHX_ "panic: pp_match start/end pointers, i=%ld, "
3073 "start=%ld, end=%ld, s=%p, strend=%p, len=%" UVuf,
3074 (long) i, (long) RXp_OFFS(prog)[i].start,
3075 (long)RXp_OFFS(prog)[i].end, s, strend, (UV) len);
3076 sv_setpvn(*SP, s, len);
3077 if (DO_UTF8(TARG) && is_utf8_string((U8*)s, len))
3082 curpos = (UV)RXp_OFFS(prog)[0].end;
3083 had_zerolen = RXp_ZERO_LEN(prog);
3084 PUTBACK; /* EVAL blocks may use stack */
3085 r_flags |= REXEC_IGNOREPOS | REXEC_NOT_FIRST;
3088 LEAVE_SCOPE(oldsave);
3091 NOT_REACHED; /* NOTREACHED */
3094 if (global && !(dynpm->op_pmflags & PMf_CONTINUE)) {
3096 mg = mg_find_mglob(TARG);
3100 LEAVE_SCOPE(oldsave);
3101 if (gimme == G_ARRAY)
3107 Perl_do_readline(pTHX)
3109 dSP; dTARGETSTACKED;
3114 IO * const io = GvIO(PL_last_in_gv);
3115 const I32 type = PL_op->op_type;
3116 const U8 gimme = GIMME_V;
3119 const MAGIC *const mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar);
3121 Perl_tied_method(aTHX_ SV_CONST(READLINE), SP, MUTABLE_SV(io), mg, gimme, 0);
3122 if (gimme == G_SCALAR) {
3124 SvSetSV_nosteal(TARG, TOPs);
3134 if (IoFLAGS(io) & IOf_ARGV) {
3135 if (IoFLAGS(io) & IOf_START) {
3137 if (av_tindex(GvAVn(PL_last_in_gv)) < 0) {
3138 IoFLAGS(io) &= ~IOf_START;
3139 do_open6(PL_last_in_gv, "-", 1, NULL, NULL, 0);
3140 SvTAINTED_off(GvSVn(PL_last_in_gv)); /* previous tainting irrelevant */
3141 sv_setpvs(GvSVn(PL_last_in_gv), "-");
3142 SvSETMAGIC(GvSV(PL_last_in_gv));
3147 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
3148 if (!fp) { /* Note: fp != IoIFP(io) */
3149 (void)do_close(PL_last_in_gv, FALSE); /* now it does*/
3152 else if (type == OP_GLOB)
3153 fp = Perl_start_glob(aTHX_ POPs, io);
3155 else if (type == OP_GLOB)
3157 else if (IoTYPE(io) == IoTYPE_WRONLY) {
3158 report_wrongway_fh(PL_last_in_gv, '>');
3162 if ((!io || !(IoFLAGS(io) & IOf_START))
3163 && ckWARN(WARN_CLOSED)
3166 report_evil_fh(PL_last_in_gv);
3168 if (gimme == G_SCALAR) {
3169 /* undef TARG, and push that undefined value */
3170 if (type != OP_RCATLINE) {
3178 if (gimme == G_SCALAR) {
3180 if (type == OP_RCATLINE && SvGMAGICAL(sv))
3183 if (type == OP_RCATLINE)
3184 SvPV_force_nomg_nolen(sv);
3188 else if (isGV_with_GP(sv)) {
3189 SvPV_force_nomg_nolen(sv);
3191 SvUPGRADE(sv, SVt_PV);
3192 tmplen = SvLEN(sv); /* remember if already alloced */
3193 if (!tmplen && !SvREADONLY(sv) && !SvIsCOW(sv)) {
3194 /* try short-buffering it. Please update t/op/readline.t
3195 * if you change the growth length.
3200 if (type == OP_RCATLINE && SvOK(sv)) {
3202 SvPV_force_nomg_nolen(sv);
3208 sv = sv_2mortal(newSV(80));
3212 /* This should not be marked tainted if the fp is marked clean */
3213 #define MAYBE_TAINT_LINE(io, sv) \
3214 if (!(IoFLAGS(io) & IOf_UNTAINT)) { \
3219 /* delay EOF state for a snarfed empty file */
3220 #define SNARF_EOF(gimme,rs,io,sv) \
3221 (gimme != G_SCALAR || SvCUR(sv) \
3222 || (IoFLAGS(io) & IOf_NOLINE) || !RsSNARF(rs))
3226 if (!sv_gets(sv, fp, offset)
3228 || SNARF_EOF(gimme, PL_rs, io, sv)
3229 || PerlIO_error(fp)))
3231 PerlIO_clearerr(fp);
3232 if (IoFLAGS(io) & IOf_ARGV) {
3233 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
3236 (void)do_close(PL_last_in_gv, FALSE);
3238 else if (type == OP_GLOB) {
3239 if (!do_close(PL_last_in_gv, FALSE)) {
3240 Perl_ck_warner(aTHX_ packWARN(WARN_GLOB),
3241 "glob failed (child exited with status %d%s)",
3242 (int)(STATUS_CURRENT >> 8),
3243 (STATUS_CURRENT & 0x80) ? ", core dumped" : "");
3246 if (gimme == G_SCALAR) {
3247 if (type != OP_RCATLINE) {
3248 SV_CHECK_THINKFIRST_COW_DROP(TARG);
3254 MAYBE_TAINT_LINE(io, sv);
3257 MAYBE_TAINT_LINE(io, sv);
3259 IoFLAGS(io) |= IOf_NOLINE;
3263 if (type == OP_GLOB) {
3267 if (SvCUR(sv) > 0 && SvCUR(PL_rs) > 0) {
3268 char * const tmps = SvEND(sv) - 1;
3269 if (*tmps == *SvPVX_const(PL_rs)) {
3271 SvCUR_set(sv, SvCUR(sv) - 1);
3274 for (t1 = SvPVX_const(sv); *t1; t1++)
3276 if (strchr("*%?", *t1))
3278 if (strchr("$&*(){}[]'\";\\|?<>~`", *t1))
3281 if (*t1 && PerlLIO_lstat(SvPVX_const(sv), &statbuf) < 0) {
3282 (void)POPs; /* Unmatched wildcard? Chuck it... */
3285 } else if (SvUTF8(sv)) { /* OP_READLINE, OP_RCATLINE */
3286 if (ckWARN(WARN_UTF8)) {
3287 const U8 * const s = (const U8*)SvPVX_const(sv) + offset;
3288 const STRLEN len = SvCUR(sv) - offset;
3291 if (!is_utf8_string_loc(s, len, &f))
3292 /* Emulate :encoding(utf8) warning in the same case. */
3293 Perl_warner(aTHX_ packWARN(WARN_UTF8),
3294 "utf8 \"\\x%02X\" does not map to Unicode",
3295 f < (U8*)SvEND(sv) ? *f : 0);
3298 if (gimme == G_ARRAY) {
3299 if (SvLEN(sv) - SvCUR(sv) > 20) {
3300 SvPV_shrink_to_cur(sv);
3302 sv = sv_2mortal(newSV(80));
3305 else if (gimme == G_SCALAR && !tmplen && SvLEN(sv) - SvCUR(sv) > 80) {
3306 /* try to reclaim a bit of scalar space (only on 1st alloc) */
3307 const STRLEN new_len
3308 = SvCUR(sv) < 60 ? 80 : SvCUR(sv)+40; /* allow some slop */
3309 SvPV_renew(sv, new_len);
3320 SV * const keysv = POPs;
3321 HV * const hv = MUTABLE_HV(POPs);
3322 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
3323 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
3325 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
3326 bool preeminent = TRUE;
3328 if (SvTYPE(hv) != SVt_PVHV)
3335 /* If we can determine whether the element exist,
3336 * Try to preserve the existenceness of a tied hash
3337 * element by using EXISTS and DELETE if possible.
3338 * Fallback to FETCH and STORE otherwise. */
3339 if (SvCANEXISTDELETE(hv))
3340 preeminent = hv_exists_ent(hv, keysv, 0);
3343 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
3344 svp = he ? &HeVAL(he) : NULL;
3346 if (!svp || !*svp || *svp == &PL_sv_undef) {
3350 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
3352 lv = sv_newmortal();
3353 sv_upgrade(lv, SVt_PVLV);
3355 sv_magic(lv, key2 = newSVsv(keysv), PERL_MAGIC_defelem, NULL, 0);
3356 SvREFCNT_dec_NN(key2); /* sv_magic() increments refcount */
3357 LvTARG(lv) = SvREFCNT_inc_simple_NN(hv);
3363 if (HvNAME_get(hv) && isGV_or_RVCV(*svp))
3364 save_gp(MUTABLE_GV(*svp), !(PL_op->op_flags & OPf_SPECIAL));
3365 else if (preeminent)
3366 save_helem_flags(hv, keysv, svp,
3367 (PL_op->op_flags & OPf_SPECIAL) ? 0 : SAVEf_SETMAGIC);
3369 SAVEHDELETE(hv, keysv);
3371 else if (PL_op->op_private & OPpDEREF) {
3372 PUSHs(vivify_ref(*svp, PL_op->op_private & OPpDEREF));
3376 sv = (svp && *svp ? *svp : &PL_sv_undef);
3377 /* Originally this did a conditional C<sv = sv_mortalcopy(sv)>; this
3378 * was to make C<local $tied{foo} = $tied{foo}> possible.
3379 * However, it seems no longer to be needed for that purpose, and
3380 * introduced a new bug: stuff like C<while ($hash{taintedval} =~ /.../g>
3381 * would loop endlessly since the pos magic is getting set on the
3382 * mortal copy and lost. However, the copy has the effect of
3383 * triggering the get magic, and losing it altogether made things like
3384 * c<$tied{foo};> in void context no longer do get magic, which some
3385 * code relied on. Also, delayed triggering of magic on @+ and friends
3386 * meant the original regex may be out of scope by now. So as a
3387 * compromise, do the get magic here. (The MGf_GSKIP flag will stop it
3388 * being called too many times). */
3389 if (!lval && SvRMAGICAL(hv) && SvGMAGICAL(sv))
3396 /* a stripped-down version of Perl_softref2xv() for use by
3397 * pp_multideref(), which doesn't use PL_op->op_flags */
3400 S_softref2xv_lite(pTHX_ SV *const sv, const char *const what,
3403 if (PL_op->op_private & HINT_STRICT_REFS) {
3405 Perl_die(aTHX_ PL_no_symref_sv, sv,
3406 (SvPOKp(sv) && SvCUR(sv)>32 ? "..." : ""), what);
3408 Perl_die(aTHX_ PL_no_usym, what);
3411 Perl_die(aTHX_ PL_no_usym, what);
3412 return gv_fetchsv_nomg(sv, GV_ADD, type);
3416 /* Handle one or more aggregate derefs and array/hash indexings, e.g.
3417 * $h->{foo} or $a[0]{$key}[$i] or f()->[1]
3419 * op_aux points to an array of unions of UV / IV / SV* / PADOFFSET.
3420 * Each of these either contains a set of actions, or an argument, such as
3421 * an IV to use as an array index, or a lexical var to retrieve.
3422 * Several actions re stored per UV; we keep shifting new actions off the
3423 * one UV, and only reload when it becomes zero.
3428 SV *sv = NULL; /* init to avoid spurious 'may be used uninitialized' */
3429 UNOP_AUX_item *items = cUNOP_AUXx(PL_op)->op_aux;
3430 UV actions = items->uv;
3433 /* this tells find_uninit_var() where we're up to */
3434 PL_multideref_pc = items;
3437 /* there are three main classes of action; the first retrieve
3438 * the initial AV or HV from a variable or the stack; the second
3439 * does the equivalent of an unrolled (/DREFAV, rv2av, aelem),
3440 * the third an unrolled (/DREFHV, rv2hv, helem).
3442 switch (actions & MDEREF_ACTION_MASK) {
3445 actions = (++items)->uv;
3448 case MDEREF_AV_padav_aelem: /* $lex[...] */
3449 sv = PAD_SVl((++items)->pad_offset);
3452 case MDEREF_AV_gvav_aelem: /* $pkg[...] */
3453 sv = UNOP_AUX_item_sv(++items);
3454 assert(isGV_with_GP(sv));
3455 sv = (SV*)GvAVn((GV*)sv);
3458 case MDEREF_AV_pop_rv2av_aelem: /* expr->[...] */
3463 goto do_AV_rv2av_aelem;
3466 case MDEREF_AV_gvsv_vivify_rv2av_aelem: /* $pkg->[...] */
3467 sv = UNOP_AUX_item_sv(++items);
3468 assert(isGV_with_GP(sv));
3469 sv = GvSVn((GV*)sv);
3470 goto do_AV_vivify_rv2av_aelem;
3472 case MDEREF_AV_padsv_vivify_rv2av_aelem: /* $lex->[...] */
3473 sv = PAD_SVl((++items)->pad_offset);
3476 do_AV_vivify_rv2av_aelem:
3477 case MDEREF_AV_vivify_rv2av_aelem: /* vivify, ->[...] */
3478 /* this is the OPpDEREF action normally found at the end of
3479 * ops like aelem, helem, rv2sv */
3480 sv = vivify_ref(sv, OPpDEREF_AV);
3484 /* this is basically a copy of pp_rv2av when it just has the
3487 if (LIKELY(SvROK(sv))) {
3488 if (UNLIKELY(SvAMAGIC(sv))) {
3489 sv = amagic_deref_call(sv, to_av_amg);
3492 if (UNLIKELY(SvTYPE(sv) != SVt_PVAV))
3493 DIE(aTHX_ "Not an ARRAY reference");
3495 else if (SvTYPE(sv) != SVt_PVAV) {
3496 if (!isGV_with_GP(sv))
3497 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "an ARRAY", SVt_PVAV);
3498 sv = MUTABLE_SV(GvAVn((GV*)sv));
3504 /* retrieve the key; this may be either a lexical or package
3505 * var (whose index/ptr is stored as an item) or a signed
3506 * integer constant stored as an item.
3509 IV elem = 0; /* to shut up stupid compiler warnings */
3512 assert(SvTYPE(sv) == SVt_PVAV);
3514 switch (actions & MDEREF_INDEX_MASK) {
3515 case MDEREF_INDEX_none:
3517 case MDEREF_INDEX_const:
3518 elem = (++items)->iv;
3520 case MDEREF_INDEX_padsv:
3521 elemsv = PAD_SVl((++items)->pad_offset);
3523 case MDEREF_INDEX_gvsv:
3524 elemsv = UNOP_AUX_item_sv(++items);
3525 assert(isGV_with_GP(elemsv));
3526 elemsv = GvSVn((GV*)elemsv);
3528 if (UNLIKELY(SvROK(elemsv) && !SvGAMAGIC(elemsv)
3529 && ckWARN(WARN_MISC)))
3530 Perl_warner(aTHX_ packWARN(WARN_MISC),
3531 "Use of reference \"%" SVf "\" as array index",
3533 /* the only time that S_find_uninit_var() needs this
3534 * is to determine which index value triggered the
3535 * undef warning. So just update it here. Note that
3536 * since we don't save and restore this var (e.g. for
3537 * tie or overload execution), its value will be
3538 * meaningless apart from just here */
3539 PL_multideref_pc = items;
3540 elem = SvIV(elemsv);
3545 /* this is basically a copy of pp_aelem with OPpDEREF skipped */
3547 if (!(actions & MDEREF_FLAG_last)) {
3548 SV** svp = av_fetch((AV*)sv, elem, 1);
3549 if (!svp || ! (sv=*svp))
3550 DIE(aTHX_ PL_no_aelem, elem);
3554 if (PL_op->op_private &
3555 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
3557 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
3558 sv = av_exists((AV*)sv, elem) ? &PL_sv_yes : &PL_sv_no;
3561 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
3562 sv = av_delete((AV*)sv, elem, discard);
3570 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
3571 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
3572 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
3573 bool preeminent = TRUE;
3574 AV *const av = (AV*)sv;
3577 if (UNLIKELY(localizing)) {
3581 /* If we can determine whether the element exist,
3582 * Try to preserve the existenceness of a tied array
3583 * element by using EXISTS and DELETE if possible.
3584 * Fallback to FETCH and STORE otherwise. */
3585 if (SvCANEXISTDELETE(av))
3586 preeminent = av_exists(av, elem);
3589 svp = av_fetch(av, elem, lval && !defer);
3592 if (!svp || !(sv = *svp)) {
3595 DIE(aTHX_ PL_no_aelem, elem);
3596 len = av_tindex(av);
3597 /* Resolve a negative index that falls within
3598 * the array. Leave it negative it if falls
3599 * outside the array. */
3600 if (elem < 0 && len + elem >= 0)
3602 if (elem >= 0 && elem <= len)
3603 /* Falls within the array. */
3604 sv = av_nonelem(av,elem);
3606 /* Falls outside the array. If it is neg-
3607 ative, magic_setdefelem will use the
3608 index for error reporting. */
3609 sv = sv_2mortal(newSVavdefelem(av,elem,1));
3612 if (UNLIKELY(localizing)) {
3614 save_aelem(av, elem, svp);
3615 sv = *svp; /* may have changed */
3618 SAVEADELETE(av, elem);
3623 sv = (svp ? *svp : &PL_sv_undef);
3624 /* see note in pp_helem() */
3625 if (SvRMAGICAL(av) && SvGMAGICAL(sv))
3642 case MDEREF_HV_padhv_helem: /* $lex{...} */
3643 sv = PAD_SVl((++items)->pad_offset);
3646 case MDEREF_HV_gvhv_helem: /* $pkg{...} */
3647 sv = UNOP_AUX_item_sv(++items);
3648 assert(isGV_with_GP(sv));
3649 sv = (SV*)GvHVn((GV*)sv);
3652 case MDEREF_HV_pop_rv2hv_helem: /* expr->{...} */
3657 goto do_HV_rv2hv_helem;
3660 case MDEREF_HV_gvsv_vivify_rv2hv_helem: /* $pkg->{...} */
3661 sv = UNOP_AUX_item_sv(++items);
3662 assert(isGV_with_GP(sv));
3663 sv = GvSVn((GV*)sv);
3664 goto do_HV_vivify_rv2hv_helem;
3666 case MDEREF_HV_padsv_vivify_rv2hv_helem: /* $lex->{...} */
3667 sv = PAD_SVl((++items)->pad_offset);
3670 do_HV_vivify_rv2hv_helem:
3671 case MDEREF_HV_vivify_rv2hv_helem: /* vivify, ->{...} */
3672 /* this is the OPpDEREF action normally found at the end of
3673 * ops like aelem, helem, rv2sv */
3674 sv = vivify_ref(sv, OPpDEREF_HV);
3678 /* this is basically a copy of pp_rv2hv when it just has the
3679 * sKR/1 flags (and pp_rv2hv is aliased to pp_rv2av) */
3682 if (LIKELY(SvROK(sv))) {
3683 if (UNLIKELY(SvAMAGIC(sv))) {
3684 sv = amagic_deref_call(sv, to_hv_amg);
3687 if (UNLIKELY(SvTYPE(sv) != SVt_PVHV))
3688 DIE(aTHX_ "Not a HASH reference");
3690 else if (SvTYPE(sv) != SVt_PVHV) {
3691 if (!isGV_with_GP(sv))
3692 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "a HASH", SVt_PVHV);
3693 sv = MUTABLE_SV(GvHVn((GV*)sv));
3699 /* retrieve the key; this may be either a lexical / package
3700 * var or a string constant, whose index/ptr is stored as an
3703 SV *keysv = NULL; /* to shut up stupid compiler warnings */
3705 assert(SvTYPE(sv) == SVt_PVHV);
3707 switch (actions & MDEREF_INDEX_MASK) {
3708 case MDEREF_INDEX_none:
3711 case MDEREF_INDEX_const:
3712 keysv = UNOP_AUX_item_sv(++items);
3715 case MDEREF_INDEX_padsv:
3716 keysv = PAD_SVl((++items)->pad_offset);
3719 case MDEREF_INDEX_gvsv:
3720 keysv = UNOP_AUX_item_sv(++items);
3721 keysv = GvSVn((GV*)keysv);
3725 /* see comment above about setting this var */
3726 PL_multideref_pc = items;
3729 /* ensure that candidate CONSTs have been HEKified */
3730 assert( ((actions & MDEREF_INDEX_MASK) != MDEREF_INDEX_const)
3731 || SvTYPE(keysv) >= SVt_PVMG
3734 || SvIsCOW_shared_hash(keysv));
3736 /* this is basically a copy of pp_helem with OPpDEREF skipped */
3738 if (!(actions & MDEREF_FLAG_last)) {
3739 HE *he = hv_fetch_ent((HV*)sv, keysv, 1, 0);
3740 if (!he || !(sv=HeVAL(he)) || sv == &PL_sv_undef)
3741 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
3745 if (PL_op->op_private &
3746 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
3748 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
3749 sv = hv_exists_ent((HV*)sv, keysv, 0)
3750 ? &PL_sv_yes : &PL_sv_no;
3753 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
3754 sv = hv_delete_ent((HV*)sv, keysv, discard, 0);
3762 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
3763 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
3764 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
3765 bool preeminent = TRUE;
3767 HV * const hv = (HV*)sv;
3770 if (UNLIKELY(localizing)) {
3774 /* If we can determine whether the element exist,
3775 * Try to preserve the existenceness of a tied hash
3776 * element by using EXISTS and DELETE if possible.
3777 * Fallback to FETCH and STORE otherwise. */
3778 if (SvCANEXISTDELETE(hv))
3779 preeminent = hv_exists_ent(hv, keysv, 0);
3782 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
3783 svp = he ? &HeVAL(he) : NULL;
3787 if (!svp || !(sv = *svp) || sv == &PL_sv_undef) {
3791 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
3792 lv = sv_newmortal();
3793 sv_upgrade(lv, SVt_PVLV);
3795 sv_magic(lv, key2 = newSVsv(keysv),
3796 PERL_MAGIC_defelem, NULL, 0);
3797 /* sv_magic() increments refcount */
3798 SvREFCNT_dec_NN(key2);
3799 LvTARG(lv) = SvREFCNT_inc_simple_NN(hv);
3805 if (HvNAME_get(hv) && isGV_or_RVCV(sv))
3806 save_gp(MUTABLE_GV(sv),
3807 !(PL_op->op_flags & OPf_SPECIAL));
3808 else if (preeminent) {
3809 save_helem_flags(hv, keysv, svp,
3810 (PL_op->op_flags & OPf_SPECIAL)
3811 ? 0 : SAVEf_SETMAGIC);
3812 sv = *svp; /* may have changed */
3815 SAVEHDELETE(hv, keysv);
3820 sv = (svp && *svp ? *svp : &PL_sv_undef);
3821 /* see note in pp_helem() */
3822 if (SvRMAGICAL(hv) && SvGMAGICAL(sv))
3831 actions >>= MDEREF_SHIFT;
3849 itersvp = CxITERVAR(cx);
3852 switch (CxTYPE(cx)) {
3854 case CXt_LOOP_LAZYSV: /* string increment */
3856 SV* cur = cx->blk_loop.state_u.lazysv.cur;
3857 SV *end = cx->blk_loop.state_u.lazysv.end;
3858 /* If the maximum is !SvOK(), pp_enteriter substitutes PL_sv_no.
3859 It has SvPVX of "" and SvCUR of 0, which is what we want. */
3861 const char *max = SvPV_const(end, maxlen);
3862 if (DO_UTF8(end) && IN_UNI_8_BIT)
3863 maxlen = sv_len_utf8_nomg(end);
3864 if (UNLIKELY(SvNIOK(cur) || SvCUR(cur) > maxlen))
3868 /* NB: on the first iteration, oldsv will have a ref count of at
3869 * least 2 (one extra from blk_loop.itersave), so the GV or pad
3870 * slot will get localised; on subsequent iterations the RC==1
3871 * optimisation may kick in and the SV will be reused. */
3872 if (oldsv && LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
3873 /* safe to reuse old SV */
3874 sv_setsv(oldsv, cur);
3878 /* we need a fresh SV every time so that loop body sees a
3879 * completely new SV for closures/references to work as
3881 *itersvp = newSVsv(cur);
3882 SvREFCNT_dec(oldsv);
3884 if (strEQ(SvPVX_const(cur), max))
3885 sv_setiv(cur, 0); /* terminate next time */
3891 case CXt_LOOP_LAZYIV: /* integer increment */
3893 IV cur = cx->blk_loop.state_u.lazyiv.cur;
3894 if (UNLIKELY(cur > cx->blk_loop.state_u.lazyiv.end))
3898 /* see NB comment above */
3899 if (oldsv && LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
3900 /* safe to reuse old SV */
3902 if ( (SvFLAGS(oldsv) & (SVTYPEMASK|SVf_THINKFIRST|SVf_IVisUV))
3905 /* Cheap SvIOK_only().
3906 * Assert that flags which SvIOK_only() would test or
3907 * clear can't be set, because we're SVt_IV */
3908 assert(!(SvFLAGS(oldsv) &
3909 (SVf_OOK|SVf_UTF8|(SVf_OK & ~(SVf_IOK|SVp_IOK)))));
3910 SvFLAGS(oldsv) |= (SVf_IOK|SVp_IOK);
3911 /* SvIV_set() where sv_any points to head */
3912 oldsv->sv_u.svu_iv = cur;
3916 sv_setiv(oldsv, cur);
3920 /* we need a fresh SV every time so that loop body sees a
3921 * completely new SV for closures/references to work as they
3923 *itersvp = newSViv(cur);
3924 SvREFCNT_dec(oldsv);
3927 if (UNLIKELY(cur == IV_MAX)) {
3928 /* Handle end of range at IV_MAX */
3929 cx->blk_loop.state_u.lazyiv.end = IV_MIN;
3931 ++cx->blk_loop.state_u.lazyiv.cur;
3935 case CXt_LOOP_LIST: /* for (1,2,3) */
3937 assert(OPpITER_REVERSED == 2); /* so inc becomes -1 or 1 */
3938 inc = (IV)1 - (IV)(PL_op->op_private & OPpITER_REVERSED);
3939 ix = (cx->blk_loop.state_u.stack.ix += inc);
3940 if (UNLIKELY(inc > 0
3941 ? ix > cx->blk_oldsp
3942 : ix <= cx->blk_loop.state_u.stack.basesp)
3946 sv = PL_stack_base[ix];
3948 goto loop_ary_common;
3950 case CXt_LOOP_ARY: /* for (@ary) */
3952 av = cx->blk_loop.state_u.ary.ary;
3953 inc = (IV)1 - (IV)(PL_op->op_private & OPpITER_REVERSED);
3954 ix = (cx->blk_loop.state_u.ary.ix += inc);
3955 if (UNLIKELY(inc > 0
3961 if (UNLIKELY(SvRMAGICAL(av))) {
3962 SV * const * const svp = av_fetch(av, ix, FALSE);
3963 sv = svp ? *svp : NULL;
3966 sv = AvARRAY(av)[ix];
3971 if (UNLIKELY(cx->cx_type & CXp_FOR_LVREF)) {
3972 SvSetMagicSV(*itersvp, sv);
3977 if (UNLIKELY(SvIS_FREED(sv))) {
3979 Perl_croak(aTHX_ "Use of freed value in iteration");
3986 SvREFCNT_inc_simple_void_NN(sv);
3990 sv = newSVavdefelem(av, ix, 0);
3997 SvREFCNT_dec(oldsv);
4001 DIE(aTHX_ "panic: pp_iter, type=%u", CxTYPE(cx));
4004 /* Try to bypass pushing &PL_sv_yes and calling pp_and(); instead
4005 * jump straight to the AND op's op_other */
4006 assert(PL_op->op_next->op_type == OP_AND);
4007 if (PL_op->op_next->op_ppaddr == Perl_pp_and) {
4008 return cLOGOPx(PL_op->op_next)->op_other;
4011 /* An XS module has replaced the op_ppaddr, so fall back to the slow,
4013 /* pp_enteriter should have pre-extended the stack */
4014 EXTEND_SKIP(PL_stack_sp, 1);
4015 *++PL_stack_sp = &PL_sv_yes;
4016 return PL_op->op_next;
4020 /* Try to bypass pushing &PL_sv_no and calling pp_and(); instead
4021 * jump straight to the AND op's op_next */
4022 assert(PL_op->op_next->op_type == OP_AND);
4023 /* pp_enteriter should have pre-extended the stack */
4024 EXTEND_SKIP(PL_stack_sp, 1);
4025 /* we only need this for the rare case where the OP_AND isn't
4026 * in void context, e.g. $x = do { for (..) {...} };
4027 * (or for when an XS module has replaced the op_ppaddr)
4028 * but it's cheaper to just push it rather than testing first
4030 *++PL_stack_sp = &PL_sv_no;
4031 if (PL_op->op_next->op_ppaddr == Perl_pp_and) {
4032 return PL_op->op_next->op_next;
4035 /* An XS module has replaced the op_ppaddr, so fall back to the slow,
4037 return PL_op->op_next;
4043 A description of how taint works in pattern matching and substitution.
4045 This is all conditional on NO_TAINT_SUPPORT not being defined. Under
4046 NO_TAINT_SUPPORT, taint-related operations should become no-ops.
4048 While the pattern is being assembled/concatenated and then compiled,
4049 PL_tainted will get set (via TAINT_set) if any component of the pattern
4050 is tainted, e.g. /.*$tainted/. At the end of pattern compilation,
4051 the RXf_TAINTED flag is set on the pattern if PL_tainted is set (via
4052 TAINT_get). It will also be set if any component of the pattern matches
4053 based on locale-dependent behavior.
4055 When the pattern is copied, e.g. $r = qr/..../, the SV holding the ref to
4056 the pattern is marked as tainted. This means that subsequent usage, such
4057 as /x$r/, will set PL_tainted using TAINT_set, and thus RXf_TAINTED,
4058 on the new pattern too.
4060 RXf_TAINTED_SEEN is used post-execution by the get magic code
4061 of $1 et al to indicate whether the returned value should be tainted.
4062 It is the responsibility of the caller of the pattern (i.e. pp_match,
4063 pp_subst etc) to set this flag for any other circumstances where $1 needs
4066 The taint behaviour of pp_subst (and pp_substcont) is quite complex.
4068 There are three possible sources of taint
4070 * the pattern (both compile- and run-time, RXf_TAINTED / RXf_TAINTED_SEEN)
4071 * the replacement string (or expression under /e)
4073 There are four destinations of taint and they are affected by the sources
4074 according to the rules below:
4076 * the return value (not including /r):
4077 tainted by the source string and pattern, but only for the
4078 number-of-iterations case; boolean returns aren't tainted;
4079 * the modified string (or modified copy under /r):
4080 tainted by the source string, pattern, and replacement strings;
4082 tainted by the pattern, and under 'use re "taint"', by the source
4084 * PL_taint - i.e. whether subsequent code (e.g. in a /e block) is tainted:
4085 should always be unset before executing subsequent code.
4087 The overall action of pp_subst is:
4089 * at the start, set bits in rxtainted indicating the taint status of
4090 the various sources.
4092 * After each pattern execution, update the SUBST_TAINT_PAT bit in
4093 rxtainted if RXf_TAINTED_SEEN has been set, to indicate that the
4094 pattern has subsequently become tainted via locale ops.
4096 * If control is being passed to pp_substcont to execute a /e block,
4097 save rxtainted in the CXt_SUBST block, for future use by
4100 * Whenever control is being returned to perl code (either by falling
4101 off the "end" of pp_subst/pp_substcont, or by entering a /e block),
4102 use the flag bits in rxtainted to make all the appropriate types of
4103 destination taint visible; e.g. set RXf_TAINTED_SEEN so that $1
4104 et al will appear tainted.
4106 pp_match is just a simpler version of the above.
4122 U8 rxtainted = 0; /* holds various SUBST_TAINT_* flag bits.
4123 See "how taint works" above */
4126 REGEXP *rx = PM_GETRE(pm);
4127 regexp *prog = ReANY(rx);
4129 int force_on_match = 0;
4130 const I32 oldsave = PL_savestack_ix;
4132 bool doutf8 = FALSE; /* whether replacement is in utf8 */
4137 /* known replacement string? */
4138 SV *dstr = (pm->op_pmflags & PMf_CONST) ? POPs : NULL;
4142 if (PL_op->op_flags & OPf_STACKED)
4153 SvGETMAGIC(TARG); /* must come before cow check */
4155 /* note that a string might get converted to COW during matching */
4156 was_cow = cBOOL(SvIsCOW(TARG));
4158 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
4159 #ifndef PERL_ANY_COW
4161 sv_force_normal_flags(TARG,0);
4163 if ((SvREADONLY(TARG)
4164 || ( ((SvTYPE(TARG) == SVt_PVGV && isGV_with_GP(TARG))
4165 || SvTYPE(TARG) > SVt_PVLV)
4166 && !(SvTYPE(TARG) == SVt_PVGV && SvFAKE(TARG)))))
4167 Perl_croak_no_modify();
4171 orig = SvPV_nomg(TARG, len);
4172 /* note we don't (yet) force the var into being a string; if we fail
4173 * to match, we leave as-is; on successful match however, we *will*
4174 * coerce into a string, then repeat the match */
4175 if (!SvPOKp(TARG) || SvTYPE(TARG) == SVt_PVGV || SvVOK(TARG))
4178 /* only replace once? */
4179 once = !(rpm->op_pmflags & PMf_GLOBAL);
4181 /* See "how taint works" above */
4184 (SvTAINTED(TARG) ? SUBST_TAINT_STR : 0)
4185 | (RXp_ISTAINTED(prog) ? SUBST_TAINT_PAT : 0)
4186 | ((pm->op_pmflags & PMf_RETAINT) ? SUBST_TAINT_RETAINT : 0)
4187 | (( (once && !(rpm->op_pmflags & PMf_NONDESTRUCT))
4188 || (PL_op->op_private & OPpTRUEBOOL)) ? SUBST_TAINT_BOOLRET : 0));
4194 DIE(aTHX_ "panic: pp_subst, pm=%p, orig=%p", pm, orig);
4196 strend = orig + len;
4197 slen = DO_UTF8(TARG) ? utf8_length((U8*)orig, (U8*)strend) : len;
4198 maxiters = 2 * slen + 10; /* We can match twice at each
4199 position, once with zero-length,
4200 second time with non-zero. */
4202 /* handle the empty pattern */
4203 if (!RX_PRELEN(rx) && PL_curpm && !prog->mother_re) {
4204 if (PL_curpm == PL_reg_curpm) {
4205 if (PL_curpm_under) {
4206 if (PL_curpm_under == PL_reg_curpm) {
4207 Perl_croak(aTHX_ "Infinite recursion via empty pattern");
4209 pm = PL_curpm_under;
4219 #ifdef PERL_SAWAMPERSAND
4220 r_flags = ( RXp_NPARENS(prog)
4222 || (RXp_EXTFLAGS(prog) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
4223 || (rpm->op_pmflags & PMf_KEEPCOPY)
4228 r_flags = REXEC_COPY_STR;
4231 if (!CALLREGEXEC(rx, orig, strend, orig, 0, TARG, NULL, r_flags))
4234 PUSHs(rpm->op_pmflags & PMf_NONDESTRUCT ? TARG : &PL_sv_no);
4235 LEAVE_SCOPE(oldsave);
4240 /* known replacement string? */
4242 /* replacement needing upgrading? */
4243 if (DO_UTF8(TARG) && !doutf8) {
4244 nsv = sv_newmortal();
4246 sv_utf8_upgrade(nsv);
4247 c = SvPV_const(nsv, clen);
4251 c = SvPV_const(dstr, clen);
4252 doutf8 = DO_UTF8(dstr);
4255 if (UNLIKELY(TAINT_get))
4256 rxtainted |= SUBST_TAINT_REPL;
4263 /* can do inplace substitution? */
4268 && (I32)clen <= RXp_MINLENRET(prog)
4270 || !(r_flags & REXEC_COPY_STR)
4271 || (!SvGMAGICAL(dstr) && !(RXp_EXTFLAGS(prog) & RXf_EVAL_SEEN))
4273 && !(RXp_EXTFLAGS(prog) & RXf_NO_INPLACE_SUBST)
4274 && (!doutf8 || SvUTF8(TARG))
4275 && !(rpm->op_pmflags & PMf_NONDESTRUCT))
4279 /* string might have got converted to COW since we set was_cow */
4280 if (SvIsCOW(TARG)) {
4281 if (!force_on_match)
4283 assert(SvVOK(TARG));
4286 if (force_on_match) {
4287 /* redo the first match, this time with the orig var
4288 * forced into being a string */
4290 orig = SvPV_force_nomg(TARG, len);
4296 if (RXp_MATCH_TAINTED(prog)) /* run time pattern taint, eg locale */
4297 rxtainted |= SUBST_TAINT_PAT;
4298 m = orig + RXp_OFFS(prog)[0].start;
4299 d = orig + RXp_OFFS(prog)[0].end;
4301 if (m - s > strend - d) { /* faster to shorten from end */
4304 Copy(c, m, clen, char);
4309 Move(d, m, i, char);
4313 SvCUR_set(TARG, m - s);
4315 else { /* faster from front */
4319 Move(s, d - i, i, char);
4322 Copy(c, d, clen, char);
4329 d = s = RXp_OFFS(prog)[0].start + orig;
4332 if (UNLIKELY(iters++ > maxiters))
4333 DIE(aTHX_ "Substitution loop");
4334 /* run time pattern taint, eg locale */
4335 if (UNLIKELY(RXp_MATCH_TAINTED(prog)))
4336 rxtainted |= SUBST_TAINT_PAT;
4337 m = RXp_OFFS(prog)[0].start + orig;
4340 Move(s, d, i, char);
4344 Copy(c, d, clen, char);
4347 s = RXp_OFFS(prog)[0].end + orig;
4348 } while (CALLREGEXEC(rx, s, strend, orig,
4349 s == m, /* don't match same null twice */
4351 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
4354 SvCUR_set(TARG, d - SvPVX_const(TARG) + i);
4355 Move(s, d, i+1, char); /* include the NUL */
4359 if (PL_op->op_private & OPpTRUEBOOL)
4369 if (force_on_match) {
4370 /* redo the first match, this time with the orig var
4371 * forced into being a string */
4373 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
4374 /* I feel that it should be possible to avoid this mortal copy
4375 given that the code below copies into a new destination.
4376 However, I suspect it isn't worth the complexity of
4377 unravelling the C<goto force_it> for the small number of
4378 cases where it would be viable to drop into the copy code. */
4379 TARG = sv_2mortal(newSVsv(TARG));
4381 orig = SvPV_force_nomg(TARG, len);
4387 if (RXp_MATCH_TAINTED(prog)) /* run time pattern taint, eg locale */
4388 rxtainted |= SUBST_TAINT_PAT;
4390 s = RXp_OFFS(prog)[0].start + orig;
4391 dstr = newSVpvn_flags(orig, s-orig,
4392 SVs_TEMP | (DO_UTF8(TARG) ? SVf_UTF8 : 0));
4397 /* note that a whole bunch of local vars are saved here for
4398 * use by pp_substcont: here's a list of them in case you're
4399 * searching for places in this sub that uses a particular var:
4400 * iters maxiters r_flags oldsave rxtainted orig dstr targ
4401 * s m strend rx once */
4403 RETURNOP(cPMOP->op_pmreplrootu.op_pmreplroot);
4407 if (UNLIKELY(iters++ > maxiters))
4408 DIE(aTHX_ "Substitution loop");
4409 if (UNLIKELY(RXp_MATCH_TAINTED(prog)))
4410 rxtainted |= SUBST_TAINT_PAT;
4411 if (RXp_MATCH_COPIED(prog) && RXp_SUBBEG(prog) != orig) {
4413 char *old_orig = orig;
4414 assert(RXp_SUBOFFSET(prog) == 0);
4416 orig = RXp_SUBBEG(prog);
4417 s = orig + (old_s - old_orig);
4418 strend = s + (strend - old_s);
4420 m = RXp_OFFS(prog)[0].start + orig;
4421 sv_catpvn_nomg_maybeutf8(dstr, s, m - s, DO_UTF8(TARG));
4422 s = RXp_OFFS(prog)[0].end + orig;
4424 /* replacement already stringified */
4426 sv_catpvn_nomg_maybeutf8(dstr, c, clen, doutf8);
4430 sv_catsv(dstr, repl);
4434 } while (CALLREGEXEC(rx, s, strend, orig,
4435 s == m, /* Yields minend of 0 or 1 */
4437 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
4438 assert(strend >= s);
4439 sv_catpvn_nomg_maybeutf8(dstr, s, strend - s, DO_UTF8(TARG));
4441 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
4442 /* From here on down we're using the copy, and leaving the original
4449 /* The match may make the string COW. If so, brilliant, because
4450 that's just saved us one malloc, copy and free - the regexp has
4451 donated the old buffer, and we malloc an entirely new one, rather
4452 than the regexp malloc()ing a buffer and copying our original,
4453 only for us to throw it away here during the substitution. */
4454 if (SvIsCOW(TARG)) {
4455 sv_force_normal_flags(TARG, SV_COW_DROP_PV);
4461 SvPV_set(TARG, SvPVX(dstr));
4462 SvCUR_set(TARG, SvCUR(dstr));
4463 SvLEN_set(TARG, SvLEN(dstr));
4464 SvFLAGS(TARG) |= SvUTF8(dstr);
4465 SvPV_set(dstr, NULL);
4468 if (PL_op->op_private & OPpTRUEBOOL)
4475 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
4476 (void)SvPOK_only_UTF8(TARG);
4479 /* See "how taint works" above */
4481 if ((rxtainted & SUBST_TAINT_PAT) ||
4482 ((rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_RETAINT)) ==
4483 (SUBST_TAINT_STR|SUBST_TAINT_RETAINT))
4485 (RXp_MATCH_TAINTED_on(prog)); /* taint $1 et al */
4487 if (!(rxtainted & SUBST_TAINT_BOOLRET)
4488 && (rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT))
4490 SvTAINTED_on(TOPs); /* taint return value */
4492 SvTAINTED_off(TOPs); /* may have got tainted earlier */
4494 /* needed for mg_set below */
4496 cBOOL(rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT|SUBST_TAINT_REPL))
4500 SvSETMAGIC(TARG); /* PL_tainted must be correctly set for this mg_set */
4502 LEAVE_SCOPE(oldsave);
4512 PL_stack_base[PL_markstack_ptr[-1]++] = PL_stack_base[*PL_markstack_ptr];
4513 ++*PL_markstack_ptr;
4515 LEAVE_with_name("grep_item"); /* exit inner scope */
4518 if (UNLIKELY(PL_stack_base + *PL_markstack_ptr > SP)) {
4520 const U8 gimme = GIMME_V;
4522 LEAVE_with_name("grep"); /* exit outer scope */
4523 (void)POPMARK; /* pop src */
4524 items = --*PL_markstack_ptr - PL_markstack_ptr[-1];
4525 (void)POPMARK; /* pop dst */
4526 SP = PL_stack_base + POPMARK; /* pop original mark */
4527 if (gimme == G_SCALAR) {
4528 if (PL_op->op_private & OPpTRUEBOOL)
4529 PUSHs(items ? &PL_sv_yes : &PL_sv_zero);
4535 else if (gimme == G_ARRAY)
4542 ENTER_with_name("grep_item"); /* enter inner scope */
4545 src = PL_stack_base[TOPMARK];
4546 if (SvPADTMP(src)) {
4547 src = PL_stack_base[TOPMARK] = sv_mortalcopy(src);
4553 RETURNOP(cLOGOP->op_other);
4557 /* leave_adjust_stacks():
4559 * Process a scope's return args (in the range from_sp+1 .. PL_stack_sp),
4560 * positioning them at to_sp+1 onwards, and do the equivalent of a
4561 * FREEMPS and TAINT_NOT.
4563 * Not intended to be called in void context.
4565 * When leaving a sub, eval, do{} or other scope, the things that need
4566 * doing to process the return args are:
4567 * * in scalar context, only return the last arg (or PL_sv_undef if none);
4568 * * for the types of return that return copies of their args (such
4569 * as rvalue sub return), make a mortal copy of every return arg,
4570 * except where we can optimise the copy away without it being
4571 * semantically visible;
4572 * * make sure that the arg isn't prematurely freed; in the case of an
4573 * arg not copied, this may involve mortalising it. For example, in
4574 * C<sub f { my $x = ...; $x }>, $x would be freed when we do
4575 * CX_LEAVE_SCOPE(cx) unless it's protected or copied.
4577 * What condition to use when deciding whether to pass the arg through
4578 * or make a copy, is determined by the 'pass' arg; its valid values are:
4579 * 0: rvalue sub/eval exit
4580 * 1: other rvalue scope exit
4581 * 2: :lvalue sub exit in rvalue context
4582 * 3: :lvalue sub exit in lvalue context and other lvalue scope exits
4584 * There is a big issue with doing a FREETMPS. We would like to free any
4585 * temps created by the last statement which the sub executed, rather than
4586 * leaving them for the caller. In a situation where a sub call isn't
4587 * soon followed by a nextstate (e.g. nested recursive calls, a la
4588 * fibonacci()), temps can accumulate, causing memory and performance
4591 * On the other hand, we don't want to free any TEMPs which are keeping
4592 * alive any return args that we skipped copying; nor do we wish to undo
4593 * any mortalising done here.
4595 * The solution is to split the temps stack frame into two, with a cut
4596 * point delineating the two halves. We arrange that by the end of this
4597 * function, all the temps stack frame entries we wish to keep are in the
4598 * range PL_tmps_floor+1.. tmps_base-1, while the ones to free now are in
4599 * the range tmps_base .. PL_tmps_ix. During the course of this
4600 * function, tmps_base starts off as PL_tmps_floor+1, then increases
4601 * whenever we find or create a temp that we know should be kept. In
4602 * general the stuff above tmps_base is undecided until we reach the end,
4603 * and we may need a sort stage for that.
4605 * To determine whether a TEMP is keeping a return arg alive, every
4606 * arg that is kept rather than copied and which has the SvTEMP flag
4607 * set, has the flag temporarily unset, to mark it. At the end we scan
4608 * the temps stack frame above the cut for entries without SvTEMP and
4609 * keep them, while turning SvTEMP on again. Note that if we die before
4610 * the SvTEMPs flags are set again, its safe: at worst, subsequent use of
4611 * those SVs may be slightly less efficient.
4613 * In practice various optimisations for some common cases mean we can
4614 * avoid most of the scanning and swapping about with the temps stack.
4618 Perl_leave_adjust_stacks(pTHX_ SV **from_sp, SV **to_sp, U8 gimme, int pass)
4622 SSize_t tmps_base; /* lowest index into tmps stack that needs freeing now */
4625 PERL_ARGS_ASSERT_LEAVE_ADJUST_STACKS;
4629 if (gimme == G_ARRAY) {
4630 nargs = SP - from_sp;
4634 assert(gimme == G_SCALAR);
4635 if (UNLIKELY(from_sp >= SP)) {
4636 /* no return args */
4637 assert(from_sp == SP);
4639 *++SP = &PL_sv_undef;
4649 /* common code for G_SCALAR and G_ARRAY */
4651 tmps_base = PL_tmps_floor + 1;
4655 /* pointer version of tmps_base. Not safe across temp stack
4659 EXTEND_MORTAL(nargs); /* one big extend for worst-case scenario */
4660 tmps_basep = PL_tmps_stack + tmps_base;
4662 /* process each return arg */
4665 SV *sv = *from_sp++;
4667 assert(PL_tmps_ix + nargs < PL_tmps_max);
4669 /* PADTMPs with container set magic shouldn't appear in the
4670 * wild. This assert is more important for pp_leavesublv(),
4671 * but by testing for it here, we're more likely to catch
4672 * bad cases (what with :lvalue subs not being widely
4673 * deployed). The two issues are that for something like
4674 * sub :lvalue { $tied{foo} }
4676 * sub :lvalue { substr($foo,1,2) }
4677 * pp_leavesublv() will croak if the sub returns a PADTMP,
4678 * and currently functions like pp_substr() return a mortal
4679 * rather than using their PADTMP when returning a PVLV.
4680 * This is because the PVLV will hold a ref to $foo,
4681 * so $foo would get delayed in being freed while
4682 * the PADTMP SV remained in the PAD.
4683 * So if this assert fails it means either:
4684 * 1) there is pp code similar to pp_substr that is
4685 * returning a PADTMP instead of a mortal, and probably
4687 * 2) pp_leavesublv is making unwarranted assumptions
4688 * about always croaking on a PADTMP
4690 if (SvPADTMP(sv) && SvSMAGICAL(sv)) {
4692 for (mg = SvMAGIC(sv); mg; mg = mg->mg_moremagic) {
4693 assert(PERL_MAGIC_TYPE_IS_VALUE_MAGIC(mg->mg_type));
4699 pass == 0 ? (SvTEMP(sv) && !SvMAGICAL(sv) && SvREFCNT(sv) == 1)
4700 : pass == 1 ? ((SvTEMP(sv) || SvPADTMP(sv)) && !SvMAGICAL(sv) && SvREFCNT(sv) == 1)
4701 : pass == 2 ? (!SvPADTMP(sv))
4704 /* pass through: skip copy for logic or optimisation
4705 * reasons; instead mortalise it, except that ... */
4709 /* ... since this SV is an SvTEMP , we don't need to
4710 * re-mortalise it; instead we just need to ensure
4711 * that its existing entry in the temps stack frame
4712 * ends up below the cut and so avoids being freed
4713 * this time round. We mark it as needing to be kept
4714 * by temporarily unsetting SvTEMP; then at the end,
4715 * we shuffle any !SvTEMP entries on the tmps stack
4716 * back below the cut.
4717 * However, there's a significant chance that there's
4718 * a 1:1 correspondence between the first few (or all)
4719 * elements in the return args stack frame and those
4720 * in the temps stack frame; e,g.:
4721 * sub f { ....; map {...} .... },
4722 * or if we're exiting multiple scopes and one of the
4723 * inner scopes has already made mortal copies of each
4726 * If so, this arg sv will correspond to the next item
4727 * on the tmps stack above the cut, and so can be kept
4728 * merely by moving the cut boundary up one, rather
4729 * than messing with SvTEMP. If all args are 1:1 then
4730 * we can avoid the sorting stage below completely.
4732 * If there are no items above the cut on the tmps
4733 * stack, then the SvTEMP must comne from an item
4734 * below the cut, so there's nothing to do.
4736 if (tmps_basep <= &PL_tmps_stack[PL_tmps_ix]) {
4737 if (sv == *tmps_basep)
4743 else if (!SvPADTMP(sv)) {
4744 /* mortalise arg to avoid it being freed during save
4745 * stack unwinding. Pad tmps don't need mortalising as
4746 * they're never freed. This is the equivalent of
4747 * sv_2mortal(SvREFCNT_inc(sv)), except that:
4748 * * it assumes that the temps stack has already been
4750 * * it puts the new item at the cut rather than at
4751 * ++PL_tmps_ix, moving the previous occupant there
4754 if (!SvIMMORTAL(sv)) {
4755 SvREFCNT_inc_simple_void_NN(sv);
4757 /* Note that if there's nothing above the cut,
4758 * this copies the garbage one slot above
4759 * PL_tmps_ix onto itself. This is harmless (the
4760 * stack's already been extended), but might in
4761 * theory trigger warnings from tools like ASan
4763 PL_tmps_stack[++PL_tmps_ix] = *tmps_basep;
4769 /* Make a mortal copy of the SV.
4770 * The following code is the equivalent of sv_mortalcopy()
4772 * * it assumes the temps stack has already been extended;
4773 * * it optimises the copying for some simple SV types;
4774 * * it puts the new item at the cut rather than at
4775 * ++PL_tmps_ix, moving the previous occupant there
4778 SV *newsv = newSV(0);
4780 PL_tmps_stack[++PL_tmps_ix] = *tmps_basep;
4781 /* put it on the tmps stack early so it gets freed if we die */
4782 *tmps_basep++ = newsv;
4785 if (SvTYPE(sv) <= SVt_IV) {
4786 /* arg must be one of undef, IV/UV, or RV: skip
4787 * sv_setsv_flags() and do the copy directly */
4789 U32 srcflags = SvFLAGS(sv);
4791 assert(!SvGMAGICAL(sv));
4792 if (srcflags & (SVf_IOK|SVf_ROK)) {
4793 SET_SVANY_FOR_BODYLESS_IV(newsv);
4795 if (srcflags & SVf_ROK) {
4796 newsv->sv_u.svu_rv = SvREFCNT_inc(SvRV(sv));
4797 /* SV type plus flags */
4798 dstflags = (SVt_IV|SVf_ROK|SVs_TEMP);
4801 /* both src and dst are <= SVt_IV, so sv_any
4802 * points to the head; so access the heads
4803 * directly rather than going via sv_any.
4805 assert( &(sv->sv_u.svu_iv)
4806 == &(((XPVIV*) SvANY(sv))->xiv_iv));
4807 assert( &(newsv->sv_u.svu_iv)
4808 == &(((XPVIV*) SvANY(newsv))->xiv_iv));
4809 newsv->sv_u.svu_iv = sv->sv_u.svu_iv;
4810 /* SV type plus flags */
4811 dstflags = (SVt_IV|SVf_IOK|SVp_IOK|SVs_TEMP
4812 |(srcflags & SVf_IVisUV));
4816 assert(!(srcflags & SVf_OK));
4817 dstflags = (SVt_NULL|SVs_TEMP); /* SV type plus flags */
4819 SvFLAGS(newsv) = dstflags;
4823 /* do the full sv_setsv() */
4827 old_base = tmps_basep - PL_tmps_stack;
4829 sv_setsv_flags(newsv, sv, SV_DO_COW_SVSETSV);
4830 /* the mg_get or sv_setsv might have created new temps
4831 * or realloced the tmps stack; regrow and reload */
4832 EXTEND_MORTAL(nargs);
4833 tmps_basep = PL_tmps_stack + old_base;
4834 TAINT_NOT; /* Each item is independent */
4840 /* If there are any temps left above the cut, we need to sort
4841 * them into those to keep and those to free. The only ones to
4842 * keep are those for which we've temporarily unset SvTEMP.
4843 * Work inwards from the two ends at tmps_basep .. PL_tmps_ix,
4844 * swapping pairs as necessary. Stop when we meet in the middle.
4847 SV **top = PL_tmps_stack + PL_tmps_ix;
4848 while (tmps_basep <= top) {
4861 tmps_base = tmps_basep - PL_tmps_stack;
4864 PL_stack_sp = to_sp;
4866 /* unrolled FREETMPS() but using tmps_base-1 rather than PL_tmps_floor */
4867 while (PL_tmps_ix >= tmps_base) {
4868 SV* const sv = PL_tmps_stack[PL_tmps_ix--];
4870 PoisonWith(PL_tmps_stack + PL_tmps_ix + 1, 1, SV *, 0xAB);
4874 SvREFCNT_dec_NN(sv); /* note, can modify tmps_ix!!! */
4880 /* also tail-called by pp_return */
4890 assert(CxTYPE(cx) == CXt_SUB);
4892 if (CxMULTICALL(cx)) {
4893 /* entry zero of a stack is always PL_sv_undef, which
4894 * simplifies converting a '()' return into undef in scalar context */
4895 assert(PL_stack_sp > PL_stack_base || *PL_stack_base == &PL_sv_undef);
4899 gimme = cx->blk_gimme;
4900 oldsp = PL_stack_base + cx->blk_oldsp; /* last arg of previous frame */
4902 if (gimme == G_VOID)
4903 PL_stack_sp = oldsp;
4905 leave_adjust_stacks(oldsp, oldsp, gimme, 0);
4908 cx_popsub(cx); /* Stack values are safe: release CV and @_ ... */
4910 retop = cx->blk_sub.retop;
4917 /* clear (if possible) or abandon the current @_. If 'abandon' is true,
4918 * forces an abandon */
4921 Perl_clear_defarray(pTHX_ AV* av, bool abandon)
4923 const SSize_t fill = AvFILLp(av);
4925 PERL_ARGS_ASSERT_CLEAR_DEFARRAY;
4927 if (LIKELY(!abandon && SvREFCNT(av) == 1 && !SvMAGICAL(av))) {
4932 AV *newav = newAV();
4933 av_extend(newav, fill);
4934 AvREIFY_only(newav);
4935 PAD_SVl(0) = MUTABLE_SV(newav);
4936 SvREFCNT_dec_NN(av);
4947 I32 old_savestack_ix;
4952 /* Locate the CV to call:
4953 * - most common case: RV->CV: f(), $ref->():
4954 * note that if a sub is compiled before its caller is compiled,
4955 * the stash entry will be a ref to a CV, rather than being a GV.
4956 * - second most common case: CV: $ref->method()
4959 /* a non-magic-RV -> CV ? */
4960 if (LIKELY( (SvFLAGS(sv) & (SVf_ROK|SVs_GMG)) == SVf_ROK)) {
4961 cv = MUTABLE_CV(SvRV(sv));
4962 if (UNLIKELY(SvOBJECT(cv))) /* might be overloaded */
4966 cv = MUTABLE_CV(sv);
4969 if (UNLIKELY(SvTYPE(cv) != SVt_PVCV)) {
4970 /* handle all the weird cases */
4971 switch (SvTYPE(sv)) {
4973 if (!isGV_with_GP(sv))
4977 cv = GvCVu((const GV *)sv);
4978 if (UNLIKELY(!cv)) {
4980 cv = sv_2cv(sv, &stash, &gv, 0);
4982 old_savestack_ix = PL_savestack_ix;
4993 if (UNLIKELY(SvAMAGIC(sv))) {
4994 sv = amagic_deref_call(sv, to_cv_amg);
4995 /* Don't SPAGAIN here. */
5001 if (UNLIKELY(!SvOK(sv)))
5002 DIE(aTHX_ PL_no_usym, "a subroutine");
5004 sym = SvPV_nomg_const(sv, len);
5005 if (PL_op->op_private & HINT_STRICT_REFS)
5006 DIE(aTHX_ "Can't use string (\"%" SVf32 "\"%s) as a subroutine ref while \"strict refs\" in use", sv, len>32 ? "..." : "");
5007 cv = get_cvn_flags(sym, len, GV_ADD|SvUTF8(sv));
5010 cv = MUTABLE_CV(SvRV(sv));
5011 if (LIKELY(SvTYPE(cv) == SVt_PVCV))
5017 DIE(aTHX_ "Not a CODE reference");
5021 /* At this point we want to save PL_savestack_ix, either by doing a
5022 * cx_pushsub(), or for XS, doing an ENTER. But we don't yet know the final
5023 * CV we will be using (so we don't know whether its XS, so we can't
5024 * cx_pushsub() or ENTER yet), and determining cv may itself push stuff on
5025 * the save stack. So remember where we are currently on the save
5026 * stack, and later update the CX or scopestack entry accordingly. */
5027 old_savestack_ix = PL_savestack_ix;
5029 /* these two fields are in a union. If they ever become separate,
5030 * we have to test for both of them being null below */
5032 assert((void*)&CvROOT(cv) == (void*)&CvXSUB(cv));
5033 while (UNLIKELY(!CvROOT(cv))) {
5037 /* anonymous or undef'd function leaves us no recourse */
5038 if (CvLEXICAL(cv) && CvHASGV(cv))
5039 DIE(aTHX_ "Undefined subroutine &%" SVf " called",
5040 SVfARG(cv_name(cv, NULL, 0)));
5041 if (CvANON(cv) || !CvHASGV(cv)) {
5042 DIE(aTHX_ "Undefined subroutine called");
5045 /* autoloaded stub? */
5046 if (cv != GvCV(gv = CvGV(cv))) {
5049 /* should call AUTOLOAD now? */
5052 autogv = gv_autoload_pvn(GvSTASH(gv), GvNAME(gv), GvNAMELEN(gv),
5053 (GvNAMEUTF8(gv) ? SVf_UTF8 : 0)
5054 |(PL_op->op_flags & OPf_REF
5055 ? GV_AUTOLOAD_ISMETHOD
5057 cv = autogv ? GvCV(autogv) : NULL;
5060 sub_name = sv_newmortal();
5061 gv_efullname3(sub_name, gv, NULL);
5062 DIE(aTHX_ "Undefined subroutine &%" SVf " called", SVfARG(sub_name));
5066 /* unrolled "CvCLONE(cv) && ! CvCLONED(cv)" */
5067 if (UNLIKELY((CvFLAGS(cv) & (CVf_CLONE|CVf_CLONED)) == CVf_CLONE))
5068 DIE(aTHX_ "Closure prototype called");
5070 if (UNLIKELY((PL_op->op_private & OPpENTERSUB_DB) && GvCV(PL_DBsub)
5073 Perl_get_db_sub(aTHX_ &sv, cv);
5075 PL_curcopdb = PL_curcop;
5077 /* check for lsub that handles lvalue subroutines */
5078 cv = GvCV(gv_fetchpvs("DB::lsub", GV_ADDMULTI, SVt_PVCV));
5079 /* if lsub not found then fall back to DB::sub */
5080 if (!cv) cv = GvCV(PL_DBsub);
5082 cv = GvCV(PL_DBsub);
5085 if (!cv || (!CvXSUB(cv) && !CvSTART(cv)))
5086 DIE(aTHX_ "No DB::sub routine defined");
5089 if (!(CvISXSUB(cv))) {
5090 /* This path taken at least 75% of the time */
5097 /* keep PADTMP args alive throughout the call (we need to do this
5098 * because @_ isn't refcounted). Note that we create the mortals
5099 * in the caller's tmps frame, so they won't be freed until after
5100 * we return from the sub.
5109 *svp = sv = sv_mortalcopy(sv);
5115 cx = cx_pushblock(CXt_SUB, gimme, MARK, old_savestack_ix);
5116 hasargs = cBOOL(PL_op->op_flags & OPf_STACKED);
5117 cx_pushsub(cx, cv, PL_op->op_next, hasargs);
5119 padlist = CvPADLIST(cv);
5120 if (UNLIKELY((depth = ++CvDEPTH(cv)) >= 2))
5121 pad_push(padlist, depth);
5122 PAD_SET_CUR_NOSAVE(padlist, depth);
5123 if (LIKELY(hasargs)) {
5124 AV *const av = MUTABLE_AV(PAD_SVl(0));
5128 defavp = &GvAV(PL_defgv);
5129 cx->blk_sub.savearray = *defavp;
5130 *defavp = MUTABLE_AV(SvREFCNT_inc_simple_NN(av));
5132 /* it's the responsibility of whoever leaves a sub to ensure
5133 * that a clean, empty AV is left in pad[0]. This is normally
5134 * done by cx_popsub() */
5135 assert(!AvREAL(av) && AvFILLp(av) == -1);
5138 if (UNLIKELY(items - 1 > AvMAX(av))) {
5139 SV **ary = AvALLOC(av);
5140 Renew(ary, items, SV*);
5141 AvMAX(av) = items - 1;
5147 Copy(MARK+1,AvARRAY(av),items,SV*);
5148 AvFILLp(av) = items - 1;
5150 if (UNLIKELY((cx->blk_u16 & OPpENTERSUB_LVAL_MASK) == OPpLVAL_INTRO &&
5152 DIE(aTHX_ "Can't modify non-lvalue subroutine call of &%" SVf,
5153 SVfARG(cv_name(cv, NULL, 0)));
5154 /* warning must come *after* we fully set up the context
5155 * stuff so that __WARN__ handlers can safely dounwind()
5158 if (UNLIKELY(depth == PERL_SUB_DEPTH_WARN
5159 && ckWARN(WARN_RECURSION)
5160 && !(PERLDB_SUB && cv == GvCV(PL_DBsub))))
5161 sub_crush_depth(cv);
5162 RETURNOP(CvSTART(cv));
5165 SSize_t markix = TOPMARK;
5169 /* pretend we did the ENTER earlier */
5170 PL_scopestack[PL_scopestack_ix - 1] = old_savestack_ix;
5175 if (UNLIKELY(((PL_op->op_private
5176 & CX_PUSHSUB_GET_LVALUE_MASK(Perl_is_lvalue_sub)
5177 ) & OPpENTERSUB_LVAL_MASK) == OPpLVAL_INTRO &&
5179 DIE(aTHX_ "Can't modify non-lvalue subroutine call of &%" SVf,
5180 SVfARG(cv_name(cv, NULL, 0)));
5182 if (UNLIKELY(!(PL_op->op_flags & OPf_STACKED) && GvAV(PL_defgv))) {
5183 /* Need to copy @_ to stack. Alternative may be to
5184 * switch stack to @_, and copy return values
5185 * back. This would allow popping @_ in XSUB, e.g.. XXXX */
5186 AV * const av = GvAV(PL_defgv);
5187 const SSize_t items = AvFILL(av) + 1;
5191 const bool m = cBOOL(SvRMAGICAL(av));
5192 /* Mark is at the end of the stack. */
5194 for (; i < items; ++i)
5198 SV ** const svp = av_fetch(av, i, 0);
5199 sv = svp ? *svp : NULL;
5201 else sv = AvARRAY(av)[i];
5202 if (sv) SP[i+1] = sv;
5204 SP[i+1] = av_nonelem(av, i);
5212 SV **mark = PL_stack_base + markix;
5213 SSize_t items = SP - mark;
5216 if (*mark && SvPADTMP(*mark)) {
5217 *mark = sv_mortalcopy(*mark);
5221 /* We assume first XSUB in &DB::sub is the called one. */
5222 if (UNLIKELY(PL_curcopdb)) {
5223 SAVEVPTR(PL_curcop);
5224 PL_curcop = PL_curcopdb;
5227 /* Do we need to open block here? XXXX */
5229 /* calculate gimme here as PL_op might get changed and then not
5230 * restored until the LEAVE further down */
5231 is_scalar = (GIMME_V == G_SCALAR);
5233 /* CvXSUB(cv) must not be NULL because newXS() refuses NULL xsub address */
5235 CvXSUB(cv)(aTHX_ cv);
5237 #if defined DEBUGGING && !defined DEBUGGING_RE_ONLY
5238 /* This duplicates the check done in runops_debug(), but provides more
5239 * information in the common case of the fault being with an XSUB.
5241 * It should also catch an XSUB pushing more than it extends
5242 * in scalar context.
5244 if (PL_curstackinfo->si_stack_hwm < PL_stack_sp - PL_stack_base)
5245 Perl_croak_nocontext(
5246 "panic: XSUB %s::%s (%s) failed to extend arg stack: "
5247 "base=%p, sp=%p, hwm=%p\n",
5248 HvNAME(GvSTASH(CvGV(cv))), GvNAME(CvGV(cv)), CvFILE(cv),
5249 PL_stack_base, PL_stack_sp,
5250 PL_stack_base + PL_curstackinfo->si_stack_hwm);
5252 /* Enforce some sanity in scalar context. */
5254 SV **svp = PL_stack_base + markix + 1;
5255 if (svp != PL_stack_sp) {
5256 *svp = svp > PL_stack_sp ? &PL_sv_undef : *PL_stack_sp;
5266 Perl_sub_crush_depth(pTHX_ CV *cv)
5268 PERL_ARGS_ASSERT_SUB_CRUSH_DEPTH;
5271 Perl_warner(aTHX_ packWARN(WARN_RECURSION), "Deep recursion on anonymous subroutine");
5273 Perl_warner(aTHX_ packWARN(WARN_RECURSION), "Deep recursion on subroutine \"%" SVf "\"",
5274 SVfARG(cv_name(cv,NULL,0)));
5280 /* like croak, but report in context of caller */
5283 Perl_croak_caller(const char *pat, ...)
5287 const PERL_CONTEXT *cx = caller_cx(0, NULL);
5289 /* make error appear at call site */
5291 PL_curcop = cx->blk_oldcop;
5293 va_start(args, pat);
5295 NOT_REACHED; /* NOTREACHED */
5304 SV* const elemsv = POPs;
5305 IV elem = SvIV(elemsv);
5306 AV *const av = MUTABLE_AV(POPs);
5307 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
5308 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
5309 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
5310 bool preeminent = TRUE;
5313 if (UNLIKELY(SvROK(elemsv) && !SvGAMAGIC(elemsv) && ckWARN(WARN_MISC)))
5314 Perl_warner(aTHX_ packWARN(WARN_MISC),
5315 "Use of reference \"%" SVf "\" as array index",
5317 if (UNLIKELY(SvTYPE(av) != SVt_PVAV))
5320 if (UNLIKELY(localizing)) {
5324 /* If we can determine whether the element exist,
5325 * Try to preserve the existenceness of a tied array
5326 * element by using EXISTS and DELETE if possible.
5327 * Fallback to FETCH and STORE otherwise. */
5328 if (SvCANEXISTDELETE(av))
5329 preeminent = av_exists(av, elem);
5332 svp = av_fetch(av, elem, lval && !defer);
5334 #ifdef PERL_MALLOC_WRAP
5335 if (SvUOK(elemsv)) {
5336 const UV uv = SvUV(elemsv);
5337 elem = uv > IV_MAX ? IV_MAX : uv;
5339 else if (SvNOK(elemsv))
5340 elem = (IV)SvNV(elemsv);
5342 MEM_WRAP_CHECK_s(elem,SV*,"Out of memory during array extend");
5345 if (!svp || !*svp) {
5348 DIE(aTHX_ PL_no_aelem, elem);
5349 len = av_tindex(av);
5350 /* Resolve a negative index that falls within the array. Leave
5351 it negative it if falls outside the array. */
5352 if (elem < 0 && len + elem >= 0)
5354 if (elem >= 0 && elem <= len)
5355 /* Falls within the array. */
5356 PUSHs(av_nonelem(av,elem));
5358 /* Falls outside the array. If it is negative,
5359 magic_setdefelem will use the index for error reporting.
5361 mPUSHs(newSVavdefelem(av, elem, 1));
5364 if (UNLIKELY(localizing)) {
5366 save_aelem(av, elem, svp);
5368 SAVEADELETE(av, elem);
5370 else if (PL_op->op_private & OPpDEREF) {
5371 PUSHs(vivify_ref(*svp, PL_op->op_private & OPpDEREF));
5375 sv = (svp ? *svp : &PL_sv_undef);
5376 if (!lval && SvRMAGICAL(av) && SvGMAGICAL(sv)) /* see note in pp_helem() */
5383 Perl_vivify_ref(pTHX_ SV *sv, U32 to_what)
5385 PERL_ARGS_ASSERT_VIVIFY_REF;
5390 Perl_croak_no_modify();
5391 prepare_SV_for_RV(sv);
5394 SvRV_set(sv, newSV(0));
5397 SvRV_set(sv, MUTABLE_SV(newAV()));
5400 SvRV_set(sv, MUTABLE_SV(newHV()));
5407 if (SvGMAGICAL(sv)) {
5408 /* copy the sv without magic to prevent magic from being
5410 SV* msv = sv_newmortal();
5411 sv_setsv_nomg(msv, sv);
5417 PERL_STATIC_INLINE HV *
5418 S_opmethod_stash(pTHX_ SV* meth)
5423 SV* const sv = PL_stack_base + TOPMARK == PL_stack_sp
5424 ? (Perl_croak(aTHX_ "Can't call method \"%" SVf "\" without a "
5425 "package or object reference", SVfARG(meth)),
5427 : *(PL_stack_base + TOPMARK + 1);
5429 PERL_ARGS_ASSERT_OPMETHOD_STASH;
5433 Perl_croak(aTHX_ "Can't call method \"%" SVf "\" on an undefined value",
5436 if (UNLIKELY(SvGMAGICAL(sv))) mg_get(sv);
5437 else if (SvIsCOW_shared_hash(sv)) { /* MyClass->meth() */
5438 stash = gv_stashsv(sv, GV_CACHE_ONLY);
5439 if (stash) return stash;
5443 ob = MUTABLE_SV(SvRV(sv));
5444 else if (!SvOK(sv)) goto undefined;
5445 else if (isGV_with_GP(sv)) {
5447 Perl_croak(aTHX_ "Can't call method \"%" SVf "\" "
5448 "without a package or object reference",
5451 if (SvTYPE(ob) == SVt_PVLV && LvTYPE(ob) == 'y') {
5452 assert(!LvTARGLEN(ob));
5456 *(PL_stack_base + TOPMARK + 1) = sv_2mortal(newRV(ob));
5459 /* this isn't a reference */
5462 const char * const packname = SvPV_nomg_const(sv, packlen);
5463 const U32 packname_utf8 = SvUTF8(sv);
5464 stash = gv_stashpvn(packname, packlen, packname_utf8 | GV_CACHE_ONLY);
5465 if (stash) return stash;
5467 if (!(iogv = gv_fetchpvn_flags(
5468 packname, packlen, packname_utf8, SVt_PVIO
5470 !(ob=MUTABLE_SV(GvIO(iogv))))
5472 /* this isn't the name of a filehandle either */
5475 Perl_croak(aTHX_ "Can't call method \"%" SVf "\" "
5476 "without a package or object reference",
5479 /* assume it's a package name */
5480 stash = gv_stashpvn(packname, packlen, packname_utf8);
5481 if (stash) return stash;
5482 else return MUTABLE_HV(sv);
5484 /* it _is_ a filehandle name -- replace with a reference */
5485 *(PL_stack_base + TOPMARK + 1) = sv_2mortal(newRV(MUTABLE_SV(iogv)));
5488 /* if we got here, ob should be an object or a glob */
5489 if (!ob || !(SvOBJECT(ob)
5490 || (isGV_with_GP(ob)
5491 && (ob = MUTABLE_SV(GvIO((const GV *)ob)))
5494 Perl_croak(aTHX_ "Can't call method \"%" SVf "\" on unblessed reference",
5495 SVfARG((SvPOK(meth) && SvPVX(meth) == PL_isa_DOES)
5496 ? newSVpvs_flags("DOES", SVs_TEMP)
5508 SV* const meth = TOPs;
5511 SV* const rmeth = SvRV(meth);
5512 if (SvTYPE(rmeth) == SVt_PVCV) {
5518 stash = opmethod_stash(meth);
5520 gv = gv_fetchmethod_sv_flags(stash, meth, GV_AUTOLOAD|GV_CROAK);
5523 SETs(isGV(gv) ? MUTABLE_SV(GvCV(gv)) : MUTABLE_SV(gv));
5527 #define METHOD_CHECK_CACHE(stash,cache,meth) \
5528 const HE* const he = hv_fetch_ent(cache, meth, 0, 0); \
5530 gv = MUTABLE_GV(HeVAL(he)); \
5531 if (isGV(gv) && GvCV(gv) && (!GvCVGEN(gv) || GvCVGEN(gv) \
5532 == (PL_sub_generation + HvMROMETA(stash)->cache_gen))) \
5534 XPUSHs(MUTABLE_SV(GvCV(gv))); \
5543 SV* const meth = cMETHOPx_meth(PL_op);
5544 HV* const stash = opmethod_stash(meth);
5546 if (LIKELY(SvTYPE(stash) == SVt_PVHV)) {
5547 METHOD_CHECK_CACHE(stash, stash, meth);
5550 gv = gv_fetchmethod_sv_flags(stash, meth, GV_AUTOLOAD|GV_CROAK);
5553 XPUSHs(isGV(gv) ? MUTABLE_SV(GvCV(gv)) : MUTABLE_SV(gv));
5562 SV* const meth = cMETHOPx_meth(PL_op);
5563 HV* const stash = CopSTASH(PL_curcop);
5564 /* Actually, SUPER doesn't need real object's (or class') stash at all,
5565 * as it uses CopSTASH. However, we must ensure that object(class) is
5566 * correct (this check is done by S_opmethod_stash) */
5567 opmethod_stash(meth);
5569 if ((cache = HvMROMETA(stash)->super)) {
5570 METHOD_CHECK_CACHE(stash, cache, meth);
5573 gv = gv_fetchmethod_sv_flags(stash, meth, GV_AUTOLOAD|GV_CROAK|GV_SUPER);
5576 XPUSHs(isGV(gv) ? MUTABLE_SV(GvCV(gv)) : MUTABLE_SV(gv));
5584 SV* const meth = cMETHOPx_meth(PL_op);
5585 HV* stash = gv_stashsv(cMETHOPx_rclass(PL_op), 0);
5586 opmethod_stash(meth); /* not used but needed for error checks */
5588 if (stash) { METHOD_CHECK_CACHE(stash, stash, meth); }
5589 else stash = MUTABLE_HV(cMETHOPx_rclass(PL_op));
5591 gv = gv_fetchmethod_sv_flags(stash, meth, GV_AUTOLOAD|GV_CROAK);
5594 XPUSHs(isGV(gv) ? MUTABLE_SV(GvCV(gv)) : MUTABLE_SV(gv));
5598 PP(pp_method_redir_super)
5603 SV* const meth = cMETHOPx_meth(PL_op);
5604 HV* stash = gv_stashsv(cMETHOPx_rclass(PL_op), 0);
5605 opmethod_stash(meth); /* not used but needed for error checks */
5607 if (UNLIKELY(!stash)) stash = MUTABLE_HV(cMETHOPx_rclass(PL_op));
5608 else if ((cache = HvMROMETA(stash)->super)) {
5609 METHOD_CHECK_CACHE(stash, cache, meth);
5612 gv = gv_fetchmethod_sv_flags(stash, meth, GV_AUTOLOAD|GV_CROAK|GV_SUPER);
5615 XPUSHs(isGV(gv) ? MUTABLE_SV(GvCV(gv)) : MUTABLE_SV(gv));
5620 * ex: set ts=8 sts=4 sw=4 et: