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Improve handling pattern compilation errors
[perl5.git] / pp_hot.c
CommitLineData
a0d0e21e
LW
1/* pp_hot.c
2 *
1129b882
NC
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
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LW
5 *
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.
8 *
9 */
10
11/*
12 * Then he heard Merry change the note, and up went the Horn-cry of Buckland,
13 * shaking the air.
14 *
4ac71550
TC
15 * Awake! Awake! Fear, Fire, Foes! Awake!
16 * Fire, Foes! Awake!
17 *
18 * [p.1007 of _The Lord of the Rings_, VI/viii: "The Scouring of the Shire"]
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LW
19 */
20
166f8a29
DM
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.
26 *
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
31 * performance.
32 */
33
a0d0e21e 34#include "EXTERN.h"
864dbfa3 35#define PERL_IN_PP_HOT_C
a0d0e21e
LW
36#include "perl.h"
37
38/* Hot code. */
39
40PP(pp_const)
41{
39644a26 42 dSP;
996c9baa 43 XPUSHs(cSVOP_sv);
a0d0e21e
LW
44 RETURN;
45}
46
47PP(pp_nextstate)
48{
533c011a 49 PL_curcop = (COP*)PL_op;
a0d0e21e 50 TAINT_NOT; /* Each statement is presumed innocent */
4ebe6e95 51 PL_stack_sp = PL_stack_base + CX_CUR()->blk_oldsp;
a0d0e21e 52 FREETMPS;
f410a211 53 PERL_ASYNC_CHECK();
a0d0e21e
LW
54 return NORMAL;
55}
56
57PP(pp_gvsv)
58{
39644a26 59 dSP;
924508f0 60 EXTEND(SP,1);
5d9574c1 61 if (UNLIKELY(PL_op->op_private & OPpLVAL_INTRO))
1d7c1841 62 PUSHs(save_scalar(cGVOP_gv));
a0d0e21e 63 else
c69033f2 64 PUSHs(GvSVn(cGVOP_gv));
a0d0e21e
LW
65 RETURN;
66}
67
b1c05ba5
DM
68
69/* also used for: pp_lineseq() pp_regcmaybe() pp_scalar() pp_scope() */
70
a0d0e21e
LW
71PP(pp_null)
72{
73 return NORMAL;
74}
75
3dd9d4e4
FC
76/* This is sometimes called directly by pp_coreargs, pp_grepstart and
77 amagic_call. */
a0d0e21e
LW
78PP(pp_pushmark)
79{
3280af22 80 PUSHMARK(PL_stack_sp);
a0d0e21e
LW
81 return NORMAL;
82}
83
84PP(pp_stringify)
85{
20b7effb 86 dSP; dTARGET;
4cc783ef
DD
87 SV * const sv = TOPs;
88 SETs(TARG);
89 sv_copypv(TARG, sv);
90 SvSETMAGIC(TARG);
91 /* no PUTBACK, SETs doesn't inc/dec SP */
92 return NORMAL;
a0d0e21e
LW
93}
94
95PP(pp_gv)
96{
20b7effb 97 dSP;
ad64d0ec 98 XPUSHs(MUTABLE_SV(cGVOP_gv));
a0d0e21e
LW
99 RETURN;
100}
101
b1c05ba5
DM
102
103/* also used for: pp_andassign() */
104
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LW
105PP(pp_and)
106{
f410a211 107 PERL_ASYNC_CHECK();
4cc783ef
DD
108 {
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;
115 if (!SvTRUE_NN(sv))
116 return NORMAL;
117 else {
118 if (PL_op->op_type == OP_AND)
119 --PL_stack_sp;
120 return cLOGOP->op_other;
121 }
a0d0e21e
LW
122 }
123}
124
125PP(pp_sassign)
126{
20b7effb 127 dSP;
3e75a3c4
RU
128 /* sassign keeps its args in the optree traditionally backwards.
129 So we pop them differently.
130 */
131 SV *left = POPs; SV *right = TOPs;
748a9306 132
354eabfa 133 if (PL_op->op_private & OPpASSIGN_BACKWARDS) { /* {or,and,dor}assign */
0bd48802
AL
134 SV * const temp = left;
135 left = right; right = temp;
a0d0e21e 136 }
d48c660d
DM
137 assert(TAINTING_get || !TAINT_get);
138 if (UNLIKELY(TAINT_get) && !SvTAINTED(right))
a0d0e21e 139 TAINT_NOT;
5d9574c1
DM
140 if (UNLIKELY(PL_op->op_private & OPpASSIGN_CV_TO_GV)) {
141 /* *foo =\&bar */
3e75a3c4 142 SV * const cv = SvRV(right);
e26df76a 143 const U32 cv_type = SvTYPE(cv);
3e75a3c4 144 const bool is_gv = isGV_with_GP(left);
6136c704 145 const bool got_coderef = cv_type == SVt_PVCV || cv_type == SVt_PVFM;
e26df76a
NC
146
147 if (!got_coderef) {
148 assert(SvROK(cv));
149 }
150
3e75a3c4
RU
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
e26df76a 153 context. */
13be902c 154 if (!got_coderef && !is_gv && GIMME_V == G_VOID) {
e26df76a 155 /* Is the target symbol table currently empty? */
3e75a3c4 156 GV * const gv = gv_fetchsv_nomg(left, GV_NOINIT, SVt_PVGV);
bb112e5a 157 if (SvTYPE(gv) != SVt_PVGV && !SvOK(gv)) {
e26df76a
NC
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);
161
ad64d0ec 162 SvUPGRADE(MUTABLE_SV(gv), SVt_IV);
1ccdb730 163 SvPCS_IMPORTED_on(gv);
e26df76a 164 SvRV_set(gv, value);
b37c2d43 165 SvREFCNT_inc_simple_void(value);
3e75a3c4 166 SETs(left);
e26df76a
NC
167 RETURN;
168 }
169 }
170
171 /* Need to fix things up. */
13be902c 172 if (!is_gv) {
e26df76a 173 /* Need to fix GV. */
3e75a3c4 174 left = MUTABLE_SV(gv_fetchsv_nomg(left,GV_ADD, SVt_PVGV));
e26df76a
NC
175 }
176
177 if (!got_coderef) {
178 /* We've been returned a constant rather than a full subroutine,
179 but they expect a subroutine reference to apply. */
53a42478 180 if (SvROK(cv)) {
d343c3ef 181 ENTER_with_name("sassign_coderef");
53a42478
NC
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.
187 */
3e75a3c4 188 SvRV_set(right, MUTABLE_SV(newCONSTSUB(GvSTASH(left), NULL,
ad64d0ec 189 SvRV(cv))));
fc2b2dca 190 SvREFCNT_dec_NN(cv);
d343c3ef 191 LEAVE_with_name("sassign_coderef");
53a42478
NC
192 } else {
193 /* What can happen for the corner case *{"BONK"} = \&{"BONK"};
194 is that
195 First: ops for \&{"BONK"}; return us the constant in the
196 symbol table
197 Second: ops for *{"BONK"} cause that symbol table entry
198 (and our reference to it) to be upgraded from RV
199 to typeblob)
200 Thirdly: We get here. cv is actually PVGV now, and its
201 GvCV() is actually the subroutine we're looking for
202
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.
205 */
159b6efe 206 GV *const upgraded = MUTABLE_GV(cv);
53a42478
NC
207 CV *const source = GvCV(upgraded);
208
209 assert(source);
210 assert(CvFLAGS(source) & CVf_CONST);
211
0ad694a7 212 SvREFCNT_inc_simple_void_NN(source);
fc2b2dca 213 SvREFCNT_dec_NN(upgraded);
3e75a3c4 214 SvRV_set(right, MUTABLE_SV(source));
53a42478 215 }
e26df76a 216 }
53a42478 217
e26df76a 218 }
8fe85e3f 219 if (
5d9574c1 220 UNLIKELY(SvTEMP(left)) && !SvSMAGICAL(left) && SvREFCNT(left) == 1 &&
3e75a3c4 221 (!isGV_with_GP(left) || SvFAKE(left)) && ckWARN(WARN_MISC)
8fe85e3f
FC
222 )
223 Perl_warner(aTHX_
224 packWARN(WARN_MISC), "Useless assignment to a temporary"
225 );
3e75a3c4
RU
226 SvSetMagicSV(left, right);
227 SETs(left);
a0d0e21e
LW
228 RETURN;
229}
230
231PP(pp_cond_expr)
232{
20b7effb 233 dSP;
f410a211 234 PERL_ASYNC_CHECK();
a0d0e21e 235 if (SvTRUEx(POPs))
1a67a97c 236 RETURNOP(cLOGOP->op_other);
a0d0e21e 237 else
1a67a97c 238 RETURNOP(cLOGOP->op_next);
a0d0e21e
LW
239}
240
241PP(pp_unstack)
242{
f5319de9 243 PERL_CONTEXT *cx;
8f3964af 244 PERL_ASYNC_CHECK();
a0d0e21e 245 TAINT_NOT; /* Each statement is presumed innocent */
4ebe6e95 246 cx = CX_CUR();
f5319de9 247 PL_stack_sp = PL_stack_base + cx->blk_oldsp;
a0d0e21e 248 FREETMPS;
eae48c89 249 if (!(PL_op->op_flags & OPf_SPECIAL)) {
93661e56 250 assert(CxTYPE(cx) == CXt_BLOCK || CxTYPE_is_LOOP(cx));
dfe0f39b 251 CX_LEAVE_SCOPE(cx);
eae48c89 252 }
a0d0e21e
LW
253 return NORMAL;
254}
255
a0d0e21e
LW
256PP(pp_concat)
257{
20b7effb 258 dSP; dATARGET; tryAMAGICbin_MG(concat_amg, AMGf_assign);
748a9306
LW
259 {
260 dPOPTOPssrl;
8d6d96c1
HS
261 bool lbyte;
262 STRLEN rlen;
d4c19fe8 263 const char *rpv = NULL;
a6b599c7 264 bool rbyte = FALSE;
a9c4fd4e 265 bool rcopied = FALSE;
8d6d96c1 266
6f1401dc
DM
267 if (TARG == right && right != left) { /* $r = $l.$r */
268 rpv = SvPV_nomg_const(right, rlen);
c75ab21a 269 rbyte = !DO_UTF8(right);
59cd0e26 270 right = newSVpvn_flags(rpv, rlen, SVs_TEMP);
349d4f2f 271 rpv = SvPV_const(right, rlen); /* no point setting UTF-8 here */
db79b45b 272 rcopied = TRUE;
8d6d96c1 273 }
7889fe52 274
89734059 275 if (TARG != left) { /* not $l .= $r */
a9c4fd4e 276 STRLEN llen;
6f1401dc 277 const char* const lpv = SvPV_nomg_const(left, llen);
90f5826e 278 lbyte = !DO_UTF8(left);
8d6d96c1
HS
279 sv_setpvn(TARG, lpv, llen);
280 if (!lbyte)
281 SvUTF8_on(TARG);
282 else
283 SvUTF8_off(TARG);
284 }
18ea7bf2
SM
285 else { /* $l .= $r and left == TARG */
286 if (!SvOK(left)) {
51f69a24
AC
287 if ((left == right /* $l .= $l */
288 || (PL_op->op_private & OPpTARGET_MY)) /* $l = $l . $r */
289 && ckWARN(WARN_UNINITIALIZED)
290 )
291 report_uninit(left);
adf14ec6 292 SvPVCLEAR(left);
c75ab21a 293 }
18ea7bf2
SM
294 else {
295 SvPV_force_nomg_nolen(left);
296 }
583a5589 297 lbyte = !DO_UTF8(left);
90f5826e 298 if (IN_BYTES)
18ea7bf2 299 SvUTF8_off(left);
8d6d96c1 300 }
a12c0f56 301
c75ab21a 302 if (!rcopied) {
6f1401dc 303 rpv = SvPV_nomg_const(right, rlen);
c75ab21a
RH
304 rbyte = !DO_UTF8(right);
305 }
8d6d96c1
HS
306 if (lbyte != rbyte) {
307 if (lbyte)
308 sv_utf8_upgrade_nomg(TARG);
309 else {
db79b45b 310 if (!rcopied)
59cd0e26 311 right = newSVpvn_flags(rpv, rlen, SVs_TEMP);
8d6d96c1 312 sv_utf8_upgrade_nomg(right);
6f1401dc 313 rpv = SvPV_nomg_const(right, rlen);
69b47968 314 }
a0d0e21e 315 }
8d6d96c1 316 sv_catpvn_nomg(TARG, rpv, rlen);
43ebc500 317
a0d0e21e
LW
318 SETTARG;
319 RETURN;
748a9306 320 }
a0d0e21e
LW
321}
322
d5524600
DM
323/* push the elements of av onto the stack.
324 * XXX Note that padav has similar code but without the mg_get().
325 * I suspect that the mg_get is no longer needed, but while padav
326 * differs, it can't share this function */
327
f9ae8fb6 328STATIC void
d5524600
DM
329S_pushav(pTHX_ AV* const av)
330{
331 dSP;
c70927a6 332 const SSize_t maxarg = AvFILL(av) + 1;
d5524600 333 EXTEND(SP, maxarg);
5d9574c1 334 if (UNLIKELY(SvRMAGICAL(av))) {
c70927a6
FC
335 PADOFFSET i;
336 for (i=0; i < (PADOFFSET)maxarg; i++) {
d5524600
DM
337 SV ** const svp = av_fetch(av, i, FALSE);
338 /* See note in pp_helem, and bug id #27839 */
339 SP[i+1] = svp
340 ? SvGMAGICAL(*svp) ? (mg_get(*svp), *svp) : *svp
341 : &PL_sv_undef;
342 }
343 }
344 else {
c70927a6
FC
345 PADOFFSET i;
346 for (i=0; i < (PADOFFSET)maxarg; i++) {
ce0d59fd 347 SV * const sv = AvARRAY(av)[i];
5d9574c1 348 SP[i+1] = LIKELY(sv) ? sv : &PL_sv_undef;
ce0d59fd 349 }
d5524600
DM
350 }
351 SP += maxarg;
352 PUTBACK;
353}
354
355
a7fd8ef6
DM
356/* ($lex1,@lex2,...) or my ($lex1,@lex2,...) */
357
358PP(pp_padrange)
359{
20b7effb 360 dSP;
a7fd8ef6
DM
361 PADOFFSET base = PL_op->op_targ;
362 int count = (int)(PL_op->op_private) & OPpPADRANGE_COUNTMASK;
363 int i;
d5524600
DM
364 if (PL_op->op_flags & OPf_SPECIAL) {
365 /* fake the RHS of my ($x,$y,..) = @_ */
366 PUSHMARK(SP);
367 S_pushav(aTHX_ GvAVn(PL_defgv));
368 SPAGAIN;
369 }
370
a7fd8ef6
DM
371 /* note, this is only skipped for compile-time-known void cxt */
372 if ((PL_op->op_flags & OPf_WANT) != OPf_WANT_VOID) {
373 EXTEND(SP, count);
374 PUSHMARK(SP);
375 for (i = 0; i <count; i++)
376 *++SP = PAD_SV(base+i);
377 }
378 if (PL_op->op_private & OPpLVAL_INTRO) {
4e09461c
DM
379 SV **svp = &(PAD_SVl(base));
380 const UV payload = (UV)(
381 (base << (OPpPADRANGE_COUNTSHIFT + SAVE_TIGHT_SHIFT))
382 | (count << SAVE_TIGHT_SHIFT)
383 | SAVEt_CLEARPADRANGE);
6d59e610 384 STATIC_ASSERT_STMT(OPpPADRANGE_COUNTMASK + 1 == (1 << OPpPADRANGE_COUNTSHIFT));
d081a355
DM
385 assert((payload >> (OPpPADRANGE_COUNTSHIFT+SAVE_TIGHT_SHIFT))
386 == (Size_t)base);
a3444cc5
DM
387 {
388 dSS_ADD;
389 SS_ADD_UV(payload);
390 SS_ADD_END(1);
391 }
4e09461c 392
a7fd8ef6 393 for (i = 0; i <count; i++)
4e09461c 394 SvPADSTALE_off(*svp++); /* mark lexical as active */
a7fd8ef6
DM
395 }
396 RETURN;
397}
398
399
a0d0e21e
LW
400PP(pp_padsv)
401{
20b7effb 402 dSP;
6c28b496
DD
403 EXTEND(SP, 1);
404 {
405 OP * const op = PL_op;
406 /* access PL_curpad once */
407 SV ** const padentry = &(PAD_SVl(op->op_targ));
408 {
409 dTARG;
410 TARG = *padentry;
411 PUSHs(TARG);
412 PUTBACK; /* no pop/push after this, TOPs ok */
8ec5e241 413 }
6c28b496
DD
414 if (op->op_flags & OPf_MOD) {
415 if (op->op_private & OPpLVAL_INTRO)
416 if (!(op->op_private & OPpPAD_STATE))
417 save_clearsv(padentry);
418 if (op->op_private & OPpDEREF) {
8f90a16d
FC
419 /* TOPs is equivalent to TARG here. Using TOPs (SP) rather
420 than TARG reduces the scope of TARG, so it does not
421 span the call to save_clearsv, resulting in smaller
422 machine code. */
6c28b496
DD
423 TOPs = vivify_ref(TOPs, op->op_private & OPpDEREF);
424 }
425 }
426 return op->op_next;
4633a7c4 427 }
a0d0e21e
LW
428}
429
430PP(pp_readline)
431{
30901a8a
FC
432 dSP;
433 if (TOPs) {
434 SvGETMAGIC(TOPs);
fc99edcf 435 tryAMAGICunTARGETlist(iter_amg, 0);
30901a8a
FC
436 PL_last_in_gv = MUTABLE_GV(*PL_stack_sp--);
437 }
438 else PL_last_in_gv = PL_argvgv, PL_stack_sp--;
6e592b3a
BM
439 if (!isGV_with_GP(PL_last_in_gv)) {
440 if (SvROK(PL_last_in_gv) && isGV_with_GP(SvRV(PL_last_in_gv)))
159b6efe 441 PL_last_in_gv = MUTABLE_GV(SvRV(PL_last_in_gv));
8efb3254 442 else {
f5284f61 443 dSP;
ad64d0ec 444 XPUSHs(MUTABLE_SV(PL_last_in_gv));
f5284f61 445 PUTBACK;
897d3989 446 Perl_pp_rv2gv(aTHX);
159b6efe 447 PL_last_in_gv = MUTABLE_GV(*PL_stack_sp--);
84ee769f
FC
448 if (PL_last_in_gv == (GV *)&PL_sv_undef)
449 PL_last_in_gv = NULL;
450 else
451 assert(isGV_with_GP(PL_last_in_gv));
f5284f61
IZ
452 }
453 }
a0d0e21e
LW
454 return do_readline();
455}
456
457PP(pp_eq)
458{
20b7effb 459 dSP;
33efebe6
DM
460 SV *left, *right;
461
a42d0242 462 tryAMAGICbin_MG(eq_amg, AMGf_set|AMGf_numeric);
33efebe6
DM
463 right = POPs;
464 left = TOPs;
465 SETs(boolSV(
466 (SvIOK_notUV(left) && SvIOK_notUV(right))
467 ? (SvIVX(left) == SvIVX(right))
468 : ( do_ncmp(left, right) == 0)
469 ));
470 RETURN;
a0d0e21e
LW
471}
472
b1c05ba5 473
4c2c3128 474/* also used for: pp_i_preinc() */
b1c05ba5 475
a0d0e21e
LW
476PP(pp_preinc)
477{
4c2c3128
DM
478 SV *sv = *PL_stack_sp;
479
480 if (LIKELY(((sv->sv_flags &
481 (SVf_THINKFIRST|SVs_GMG|SVf_IVisUV|
482 SVf_IOK|SVf_NOK|SVf_POK|SVp_NOK|SVp_POK|SVf_ROK))
483 == SVf_IOK))
484 && SvIVX(sv) != IV_MAX)
485 {
486 SvIV_set(sv, SvIVX(sv) + 1);
487 }
488 else /* Do all the PERL_PRESERVE_IVUV and hard cases in sv_inc */
489 sv_inc(sv);
490 SvSETMAGIC(sv);
491 return NORMAL;
492}
493
494
495/* also used for: pp_i_predec() */
496
497PP(pp_predec)
498{
499 SV *sv = *PL_stack_sp;
500
501 if (LIKELY(((sv->sv_flags &
502 (SVf_THINKFIRST|SVs_GMG|SVf_IVisUV|
503 SVf_IOK|SVf_NOK|SVf_POK|SVp_NOK|SVp_POK|SVf_ROK))
504 == SVf_IOK))
505 && SvIVX(sv) != IV_MIN)
55497cff 506 {
4c2c3128 507 SvIV_set(sv, SvIVX(sv) - 1);
748a9306 508 }
4c2c3128
DM
509 else /* Do all the PERL_PRESERVE_IVUV and hard cases in sv_dec */
510 sv_dec(sv);
511 SvSETMAGIC(sv);
a0d0e21e
LW
512 return NORMAL;
513}
514
b1c05ba5
DM
515
516/* also used for: pp_orassign() */
517
a0d0e21e
LW
518PP(pp_or)
519{
20b7effb 520 dSP;
f410a211 521 PERL_ASYNC_CHECK();
a0d0e21e
LW
522 if (SvTRUE(TOPs))
523 RETURN;
524 else {
c960fc3b
SP
525 if (PL_op->op_type == OP_OR)
526 --SP;
a0d0e21e
LW
527 RETURNOP(cLOGOP->op_other);
528 }
529}
530
b1c05ba5
DM
531
532/* also used for: pp_dor() pp_dorassign() */
533
25a55bd7 534PP(pp_defined)
c963b151 535{
20b7effb 536 dSP;
eb578fdb 537 SV* sv;
6136c704 538 bool defined;
25a55bd7 539 const int op_type = PL_op->op_type;
ea5195b7 540 const bool is_dor = (op_type == OP_DOR || op_type == OP_DORASSIGN);
c963b151 541
6136c704 542 if (is_dor) {
f410a211 543 PERL_ASYNC_CHECK();
25a55bd7 544 sv = TOPs;
5d9574c1 545 if (UNLIKELY(!sv || !SvANY(sv))) {
2bd49cfc
NC
546 if (op_type == OP_DOR)
547 --SP;
25a55bd7
SP
548 RETURNOP(cLOGOP->op_other);
549 }
b7c44293
RGS
550 }
551 else {
552 /* OP_DEFINED */
25a55bd7 553 sv = POPs;
5d9574c1 554 if (UNLIKELY(!sv || !SvANY(sv)))
25a55bd7 555 RETPUSHNO;
b7c44293 556 }
25a55bd7 557
6136c704 558 defined = FALSE;
c963b151
BD
559 switch (SvTYPE(sv)) {
560 case SVt_PVAV:
561 if (AvMAX(sv) >= 0 || SvGMAGICAL(sv) || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
25a55bd7 562 defined = TRUE;
c963b151
BD
563 break;
564 case SVt_PVHV:
565 if (HvARRAY(sv) || SvGMAGICAL(sv) || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
25a55bd7 566 defined = TRUE;
c963b151
BD
567 break;
568 case SVt_PVCV:
569 if (CvROOT(sv) || CvXSUB(sv))
25a55bd7 570 defined = TRUE;
c963b151
BD
571 break;
572 default:
5b295bef 573 SvGETMAGIC(sv);
c963b151 574 if (SvOK(sv))
25a55bd7 575 defined = TRUE;
6136c704 576 break;
c963b151 577 }
6136c704
AL
578
579 if (is_dor) {
c960fc3b
SP
580 if(defined)
581 RETURN;
582 if(op_type == OP_DOR)
583 --SP;
25a55bd7 584 RETURNOP(cLOGOP->op_other);
25a55bd7 585 }
d9aa96a4
SP
586 /* assuming OP_DEFINED */
587 if(defined)
588 RETPUSHYES;
589 RETPUSHNO;
c963b151
BD
590}
591
230ee21f
DM
592
593
a0d0e21e
LW
594PP(pp_add)
595{
20b7effb 596 dSP; dATARGET; bool useleft; SV *svl, *svr;
230ee21f 597
6f1401dc
DM
598 tryAMAGICbin_MG(add_amg, AMGf_assign|AMGf_numeric);
599 svr = TOPs;
600 svl = TOPm1s;
601
28e5dec8 602#ifdef PERL_PRESERVE_IVUV
230ee21f
DM
603
604 /* special-case some simple common cases */
605 if (!((svl->sv_flags|svr->sv_flags) & (SVf_IVisUV|SVs_GMG))) {
606 IV il, ir;
607 U32 flags = (svl->sv_flags & svr->sv_flags);
608 if (flags & SVf_IOK) {
609 /* both args are simple IVs */
610 UV topl, topr;
611 il = SvIVX(svl);
612 ir = SvIVX(svr);
613 do_iv:
614 topl = ((UV)il) >> (UVSIZE * 8 - 2);
615 topr = ((UV)ir) >> (UVSIZE * 8 - 2);
616
617 /* if both are in a range that can't under/overflow, do a
618 * simple integer add: if the top of both numbers
619 * are 00 or 11, then it's safe */
620 if (!( ((topl+1) | (topr+1)) & 2)) {
621 SP--;
622 TARGi(il + ir, 0); /* args not GMG, so can't be tainted */
623 SETs(TARG);
624 RETURN;
625 }
626 goto generic;
627 }
628 else if (flags & SVf_NOK) {
629 /* both args are NVs */
630 NV nl = SvNVX(svl);
631 NV nr = SvNVX(svr);
632
3336af0b
DD
633 if (
634#if defined(NAN_COMPARE_BROKEN) && defined(Perl_isnan)
635 !Perl_isnan(nl) && nl == (NV)(il = (IV)nl)
636 && !Perl_isnan(nr) && nr == (NV)(ir = (IV)nr)
637#else
638 nl == (NV)(il = (IV)nl) && nr == (NV)(ir = (IV)nr)
639#endif
640 )
230ee21f
DM
641 /* nothing was lost by converting to IVs */
642 goto do_iv;
643 SP--;
644 TARGn(nl + nr, 0); /* args not GMG, so can't be tainted */
645 SETs(TARG);
646 RETURN;
647 }
648 }
649
650 generic:
651
652 useleft = USE_LEFT(svl);
28e5dec8
JH
653 /* We must see if we can perform the addition with integers if possible,
654 as the integer code detects overflow while the NV code doesn't.
655 If either argument hasn't had a numeric conversion yet attempt to get
656 the IV. It's important to do this now, rather than just assuming that
657 it's not IOK as a PV of "9223372036854775806" may not take well to NV
658 addition, and an SV which is NOK, NV=6.0 ought to be coerced to
659 integer in case the second argument is IV=9223372036854775806
660 We can (now) rely on sv_2iv to do the right thing, only setting the
661 public IOK flag if the value in the NV (or PV) slot is truly integer.
662
663 A side effect is that this also aggressively prefers integer maths over
7dca457a
NC
664 fp maths for integer values.
665
a00b5bd3 666 How to detect overflow?
7dca457a
NC
667
668 C 99 section 6.2.6.1 says
669
670 The range of nonnegative values of a signed integer type is a subrange
671 of the corresponding unsigned integer type, and the representation of
672 the same value in each type is the same. A computation involving
673 unsigned operands can never overflow, because a result that cannot be
674 represented by the resulting unsigned integer type is reduced modulo
675 the number that is one greater than the largest value that can be
676 represented by the resulting type.
677
678 (the 9th paragraph)
679
680 which I read as "unsigned ints wrap."
681
682 signed integer overflow seems to be classed as "exception condition"
683
684 If an exceptional condition occurs during the evaluation of an
685 expression (that is, if the result is not mathematically defined or not
686 in the range of representable values for its type), the behavior is
687 undefined.
688
689 (6.5, the 5th paragraph)
690
691 I had assumed that on 2s complement machines signed arithmetic would
692 wrap, hence coded pp_add and pp_subtract on the assumption that
693 everything perl builds on would be happy. After much wailing and
694 gnashing of teeth it would seem that irix64 knows its ANSI spec well,
695 knows that it doesn't need to, and doesn't. Bah. Anyway, the all-
696 unsigned code below is actually shorter than the old code. :-)
697 */
698
01f91bf2 699 if (SvIV_please_nomg(svr)) {
28e5dec8
JH
700 /* Unless the left argument is integer in range we are going to have to
701 use NV maths. Hence only attempt to coerce the right argument if
702 we know the left is integer. */
eb578fdb 703 UV auv = 0;
9c5ffd7c 704 bool auvok = FALSE;
7dca457a
NC
705 bool a_valid = 0;
706
28e5dec8 707 if (!useleft) {
7dca457a
NC
708 auv = 0;
709 a_valid = auvok = 1;
710 /* left operand is undef, treat as zero. + 0 is identity,
711 Could SETi or SETu right now, but space optimise by not adding
712 lots of code to speed up what is probably a rarish case. */
713 } else {
714 /* Left operand is defined, so is it IV? */
01f91bf2 715 if (SvIV_please_nomg(svl)) {
800401ee
JH
716 if ((auvok = SvUOK(svl)))
717 auv = SvUVX(svl);
7dca457a 718 else {
eb578fdb 719 const IV aiv = SvIVX(svl);
7dca457a
NC
720 if (aiv >= 0) {
721 auv = aiv;
722 auvok = 1; /* Now acting as a sign flag. */
53e2bfb7
DM
723 } else {
724 auv = (aiv == IV_MIN) ? (UV)aiv : (UV)(-aiv);
7dca457a
NC
725 }
726 }
727 a_valid = 1;
28e5dec8
JH
728 }
729 }
7dca457a
NC
730 if (a_valid) {
731 bool result_good = 0;
732 UV result;
eb578fdb 733 UV buv;
800401ee 734 bool buvok = SvUOK(svr);
a00b5bd3 735
7dca457a 736 if (buvok)
800401ee 737 buv = SvUVX(svr);
7dca457a 738 else {
eb578fdb 739 const IV biv = SvIVX(svr);
7dca457a
NC
740 if (biv >= 0) {
741 buv = biv;
742 buvok = 1;
743 } else
53e2bfb7 744 buv = (biv == IV_MIN) ? (UV)biv : (UV)(-biv);
7dca457a
NC
745 }
746 /* ?uvok if value is >= 0. basically, flagged as UV if it's +ve,
602f51c4 747 else "IV" now, independent of how it came in.
7dca457a
NC
748 if a, b represents positive, A, B negative, a maps to -A etc
749 a + b => (a + b)
750 A + b => -(a - b)
751 a + B => (a - b)
752 A + B => -(a + b)
753 all UV maths. negate result if A negative.
754 add if signs same, subtract if signs differ. */
755
756 if (auvok ^ buvok) {
757 /* Signs differ. */
758 if (auv >= buv) {
759 result = auv - buv;
760 /* Must get smaller */
761 if (result <= auv)
762 result_good = 1;
763 } else {
764 result = buv - auv;
765 if (result <= buv) {
766 /* result really should be -(auv-buv). as its negation
767 of true value, need to swap our result flag */
768 auvok = !auvok;
769 result_good = 1;
28e5dec8
JH
770 }
771 }
7dca457a
NC
772 } else {
773 /* Signs same */
774 result = auv + buv;
775 if (result >= auv)
776 result_good = 1;
777 }
778 if (result_good) {
779 SP--;
780 if (auvok)
28e5dec8 781 SETu( result );
7dca457a
NC
782 else {
783 /* Negate result */
784 if (result <= (UV)IV_MIN)
53e2bfb7
DM
785 SETi(result == (UV)IV_MIN
786 ? IV_MIN : -(IV)result);
7dca457a
NC
787 else {
788 /* result valid, but out of range for IV. */
789 SETn( -(NV)result );
28e5dec8
JH
790 }
791 }
7dca457a
NC
792 RETURN;
793 } /* Overflow, drop through to NVs. */
28e5dec8
JH
794 }
795 }
230ee21f
DM
796
797#else
798 useleft = USE_LEFT(svl);
28e5dec8 799#endif
230ee21f 800
a0d0e21e 801 {
6f1401dc 802 NV value = SvNV_nomg(svr);
4efa5a16 803 (void)POPs;
28e5dec8
JH
804 if (!useleft) {
805 /* left operand is undef, treat as zero. + 0.0 is identity. */
806 SETn(value);
807 RETURN;
808 }
6f1401dc 809 SETn( value + SvNV_nomg(svl) );
28e5dec8 810 RETURN;
a0d0e21e
LW
811 }
812}
813
b1c05ba5
DM
814
815/* also used for: pp_aelemfast_lex() */
816
a0d0e21e
LW
817PP(pp_aelemfast)
818{
20b7effb 819 dSP;
93bad3fd 820 AV * const av = PL_op->op_type == OP_AELEMFAST_LEX
8f878375 821 ? MUTABLE_AV(PAD_SV(PL_op->op_targ)) : GvAVn(cGVOP_gv);
a3b680e6 822 const U32 lval = PL_op->op_flags & OPf_MOD;
7e169e84
DM
823 const I8 key = (I8)PL_op->op_private;
824 SV** svp;
825 SV *sv;
826
827 assert(SvTYPE(av) == SVt_PVAV);
828
f4484b87
DM
829 EXTEND(SP, 1);
830
7e169e84
DM
831 /* inlined av_fetch() for simple cases ... */
832 if (!SvRMAGICAL(av) && key >= 0 && key <= AvFILLp(av)) {
833 sv = AvARRAY(av)[key];
9fb994be 834 if (sv) {
7e169e84
DM
835 PUSHs(sv);
836 RETURN;
837 }
838 }
839
840 /* ... else do it the hard way */
841 svp = av_fetch(av, key, lval);
842 sv = (svp ? *svp : &PL_sv_undef);
b024352e
DM
843
844 if (UNLIKELY(!svp && lval))
7e169e84 845 DIE(aTHX_ PL_no_aelem, (int)key);
b024352e 846
39cf747a 847 if (!lval && SvRMAGICAL(av) && SvGMAGICAL(sv)) /* see note in pp_helem() */
fd69380d 848 mg_get(sv);
be6c24e0 849 PUSHs(sv);
a0d0e21e
LW
850 RETURN;
851}
852
853PP(pp_join)
854{
20b7effb 855 dSP; dMARK; dTARGET;
a0d0e21e
LW
856 MARK++;
857 do_join(TARG, *MARK, MARK, SP);
858 SP = MARK;
859 SETs(TARG);
860 RETURN;
861}
862
a0d0e21e
LW
863/* Oversized hot code. */
864
b1c05ba5
DM
865/* also used for: pp_say() */
866
a0d0e21e
LW
867PP(pp_print)
868{
20b7effb 869 dSP; dMARK; dORIGMARK;
eb578fdb 870 PerlIO *fp;
236988e4 871 MAGIC *mg;
159b6efe
NC
872 GV * const gv
873 = (PL_op->op_flags & OPf_STACKED) ? MUTABLE_GV(*++MARK) : PL_defoutgv;
9c9f25b8 874 IO *io = GvIO(gv);
5b468f54 875
9c9f25b8 876 if (io
ad64d0ec 877 && (mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar)))
5b468f54 878 {
01bb7c6d 879 had_magic:
68dc0745 880 if (MARK == ORIGMARK) {
1c846c1f 881 /* If using default handle then we need to make space to
a60c0954
NIS
882 * pass object as 1st arg, so move other args up ...
883 */
4352c267 884 MEXTEND(SP, 1);
68dc0745
PP
885 ++MARK;
886 Move(MARK, MARK + 1, (SP - MARK) + 1, SV*);
887 ++SP;
888 }
3e0cb5de 889 return Perl_tied_method(aTHX_ SV_CONST(PRINT), mark - 1, MUTABLE_SV(io),
94bc412f
NC
890 mg,
891 (G_SCALAR | TIED_METHOD_ARGUMENTS_ON_STACK
892 | (PL_op->op_type == OP_SAY
893 ? TIED_METHOD_SAY : 0)), sp - mark);
236988e4 894 }
9c9f25b8 895 if (!io) {
68b590d9 896 if ( gv && GvEGVx(gv) && (io = GvIO(GvEGV(gv)))
ad64d0ec 897 && (mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar)))
01bb7c6d 898 goto had_magic;
51087808 899 report_evil_fh(gv);
93189314 900 SETERRNO(EBADF,RMS_IFI);
a0d0e21e
LW
901 goto just_say_no;
902 }
903 else if (!(fp = IoOFP(io))) {
7716c5c5
NC
904 if (IoIFP(io))
905 report_wrongway_fh(gv, '<');
51087808 906 else
7716c5c5 907 report_evil_fh(gv);
93189314 908 SETERRNO(EBADF,IoIFP(io)?RMS_FAC:RMS_IFI);
a0d0e21e
LW
909 goto just_say_no;
910 }
911 else {
e23d9e2f 912 SV * const ofs = GvSV(PL_ofsgv); /* $, */
a0d0e21e 913 MARK++;
e23d9e2f 914 if (ofs && (SvGMAGICAL(ofs) || SvOK(ofs))) {
a0d0e21e
LW
915 while (MARK <= SP) {
916 if (!do_print(*MARK, fp))
917 break;
918 MARK++;
919 if (MARK <= SP) {
e23d9e2f
CS
920 /* don't use 'ofs' here - it may be invalidated by magic callbacks */
921 if (!do_print(GvSV(PL_ofsgv), fp)) {
a0d0e21e
LW
922 MARK--;
923 break;
924 }
925 }
926 }
927 }
928 else {
929 while (MARK <= SP) {
930 if (!do_print(*MARK, fp))
931 break;
932 MARK++;
933 }
934 }
935 if (MARK <= SP)
936 goto just_say_no;
937 else {
cfc4a7da
GA
938 if (PL_op->op_type == OP_SAY) {
939 if (PerlIO_write(fp, "\n", 1) == 0 || PerlIO_error(fp))
940 goto just_say_no;
941 }
942 else if (PL_ors_sv && SvOK(PL_ors_sv))
7889fe52 943 if (!do_print(PL_ors_sv, fp)) /* $\ */
a0d0e21e
LW
944 goto just_say_no;
945
946 if (IoFLAGS(io) & IOf_FLUSH)
760ac839 947 if (PerlIO_flush(fp) == EOF)
a0d0e21e
LW
948 goto just_say_no;
949 }
950 }
951 SP = ORIGMARK;
e52fd6f4 952 XPUSHs(&PL_sv_yes);
a0d0e21e
LW
953 RETURN;
954
955 just_say_no:
956 SP = ORIGMARK;
e52fd6f4 957 XPUSHs(&PL_sv_undef);
a0d0e21e
LW
958 RETURN;
959}
960
b1c05ba5
DM
961
962/* also used for: pp_rv2hv() */
bdaf10a5 963/* also called directly by pp_lvavref */
b1c05ba5 964
a0d0e21e
LW
965PP(pp_rv2av)
966{
20b7effb 967 dSP; dTOPss;
1c23e2bd 968 const U8 gimme = GIMME_V;
13c59d41
MH
969 static const char an_array[] = "an ARRAY";
970 static const char a_hash[] = "a HASH";
bdaf10a5
FC
971 const bool is_pp_rv2av = PL_op->op_type == OP_RV2AV
972 || PL_op->op_type == OP_LVAVREF;
d83b45b8 973 const svtype type = is_pp_rv2av ? SVt_PVAV : SVt_PVHV;
a0d0e21e 974
9026059d 975 SvGETMAGIC(sv);
a0d0e21e 976 if (SvROK(sv)) {
5d9574c1 977 if (UNLIKELY(SvAMAGIC(sv))) {
93d7320b 978 sv = amagic_deref_call(sv, is_pp_rv2av ? to_av_amg : to_hv_amg);
93d7320b 979 }
17ab7946 980 sv = SvRV(sv);
5d9574c1 981 if (UNLIKELY(SvTYPE(sv) != type))
dcbac5bb 982 /* diag_listed_as: Not an ARRAY reference */
13c59d41 983 DIE(aTHX_ "Not %s reference", is_pp_rv2av ? an_array : a_hash);
5d9574c1
DM
984 else if (UNLIKELY(PL_op->op_flags & OPf_MOD
985 && PL_op->op_private & OPpLVAL_INTRO))
3da99855 986 Perl_croak(aTHX_ "%s", PL_no_localize_ref);
a0d0e21e 987 }
5d9574c1 988 else if (UNLIKELY(SvTYPE(sv) != type)) {
67955e0c 989 GV *gv;
1c846c1f 990
6e592b3a 991 if (!isGV_with_GP(sv)) {
13c59d41 992 gv = Perl_softref2xv(aTHX_ sv, is_pp_rv2av ? an_array : a_hash,
dc3c76f8
NC
993 type, &sp);
994 if (!gv)
995 RETURN;
35cd451c
GS
996 }
997 else {
159b6efe 998 gv = MUTABLE_GV(sv);
a0d0e21e 999 }
ad64d0ec 1000 sv = is_pp_rv2av ? MUTABLE_SV(GvAVn(gv)) : MUTABLE_SV(GvHVn(gv));
533c011a 1001 if (PL_op->op_private & OPpLVAL_INTRO)
ad64d0ec 1002 sv = is_pp_rv2av ? MUTABLE_SV(save_ary(gv)) : MUTABLE_SV(save_hash(gv));
9f527363
FC
1003 }
1004 if (PL_op->op_flags & OPf_REF) {
17ab7946 1005 SETs(sv);
a0d0e21e 1006 RETURN;
9f527363 1007 }
5d9574c1 1008 else if (UNLIKELY(PL_op->op_private & OPpMAYBE_LVSUB)) {
40c94d11
FC
1009 const I32 flags = is_lvalue_sub();
1010 if (flags && !(flags & OPpENTERSUB_INARGS)) {
cde874ca 1011 if (gimme != G_ARRAY)
042560a6 1012 goto croak_cant_return;
17ab7946 1013 SETs(sv);
78f9721b 1014 RETURN;
40c94d11 1015 }
a0d0e21e
LW
1016 }
1017
17ab7946 1018 if (is_pp_rv2av) {
502c6561 1019 AV *const av = MUTABLE_AV(sv);
636fe681 1020 /* The guts of pp_rv2av */
96913b52 1021 if (gimme == G_ARRAY) {
d5524600
DM
1022 SP--;
1023 PUTBACK;
1024 S_pushav(aTHX_ av);
1025 SPAGAIN;
1c846c1f 1026 }
96913b52
VP
1027 else if (gimme == G_SCALAR) {
1028 dTARGET;
c70927a6 1029 const SSize_t maxarg = AvFILL(av) + 1;
96913b52 1030 SETi(maxarg);
93965878 1031 }
17ab7946
NC
1032 } else {
1033 /* The guts of pp_rv2hv */
96913b52
VP
1034 if (gimme == G_ARRAY) { /* array wanted */
1035 *PL_stack_sp = sv;
981b7185 1036 return Perl_do_kv(aTHX);
96913b52 1037 }
c8fe3bdf 1038 else if ((PL_op->op_private & OPpTRUEBOOL
adc42c31 1039 || ( PL_op->op_private & OPpMAYBE_TRUEBOOL
c8fe3bdf
FC
1040 && block_gimme() == G_VOID ))
1041 && (!SvRMAGICAL(sv) || !mg_find(sv, PERL_MAGIC_tied)))
1186f821 1042 SETs(HvUSEDKEYS(MUTABLE_HV(sv)) ? &PL_sv_yes : &PL_sv_no);
96913b52 1043 else if (gimme == G_SCALAR) {
1a8bdda9 1044 dTARG;
96913b52 1045 TARG = Perl_hv_scalar(aTHX_ MUTABLE_HV(sv));
96913b52
VP
1046 SETTARG;
1047 }
17ab7946 1048 }
be85d344 1049 RETURN;
042560a6
NC
1050
1051 croak_cant_return:
1052 Perl_croak(aTHX_ "Can't return %s to lvalue scalar context",
1053 is_pp_rv2av ? "array" : "hash");
77e217c6 1054 RETURN;
a0d0e21e
LW
1055}
1056
10c8fecd 1057STATIC void
fb8f4cf8 1058S_do_oddball(pTHX_ SV **oddkey, SV **firstkey)
10c8fecd 1059{
7918f24d
NC
1060 PERL_ARGS_ASSERT_DO_ODDBALL;
1061
fb8f4cf8 1062 if (*oddkey) {
6d822dc4 1063 if (ckWARN(WARN_MISC)) {
a3b680e6 1064 const char *err;
fb8f4cf8
RZ
1065 if (oddkey == firstkey &&
1066 SvROK(*oddkey) &&
1067 (SvTYPE(SvRV(*oddkey)) == SVt_PVAV ||
1068 SvTYPE(SvRV(*oddkey)) == SVt_PVHV))
10c8fecd 1069 {
a3b680e6 1070 err = "Reference found where even-sized list expected";
10c8fecd
GS
1071 }
1072 else
a3b680e6 1073 err = "Odd number of elements in hash assignment";
f1f66076 1074 Perl_warner(aTHX_ packWARN(WARN_MISC), "%s", err);
10c8fecd 1075 }
6d822dc4 1076
10c8fecd
GS
1077 }
1078}
1079
a5f48505
DM
1080
1081/* Do a mark and sweep with the SVf_BREAK flag to detect elements which
1082 * are common to both the LHS and RHS of an aassign, and replace them
1083 * with copies. All these copies are made before the actual list assign is
1084 * done.
1085 *
1086 * For example in ($a,$b) = ($b,$a), assigning the value of the first RHS
1087 * element ($b) to the first LH element ($a), modifies $a; when the
1088 * second assignment is done, the second RH element now has the wrong
1089 * value. So we initially replace the RHS with ($b, mortalcopy($a)).
1090 * Note that we don't need to make a mortal copy of $b.
1091 *
1092 * The algorithm below works by, for every RHS element, mark the
1093 * corresponding LHS target element with SVf_BREAK. Then if the RHS
1094 * element is found with SVf_BREAK set, it means it would have been
1095 * modified, so make a copy.
1096 * Note that by scanning both LHS and RHS in lockstep, we avoid
1097 * unnecessary copies (like $b above) compared with a naive
1098 * "mark all LHS; copy all marked RHS; unmark all LHS".
1099 *
1100 * If the LHS element is a 'my' declaration' and has a refcount of 1, then
1101 * it can't be common and can be skipped.
ebc643ce
DM
1102 *
1103 * On DEBUGGING builds it takes an extra boolean, fake. If true, it means
1104 * that we thought we didn't need to call S_aassign_copy_common(), but we
1105 * have anyway for sanity checking. If we find we need to copy, then panic.
a5f48505
DM
1106 */
1107
1108PERL_STATIC_INLINE void
1109S_aassign_copy_common(pTHX_ SV **firstlelem, SV **lastlelem,
ebc643ce
DM
1110 SV **firstrelem, SV **lastrelem
1111#ifdef DEBUGGING
1112 , bool fake
1113#endif
1114)
a5f48505
DM
1115{
1116 dVAR;
1117 SV **relem;
1118 SV **lelem;
1119 SSize_t lcount = lastlelem - firstlelem + 1;
1120 bool marked = FALSE; /* have we marked any LHS with SVf_BREAK ? */
1121 bool const do_rc1 = cBOOL(PL_op->op_private & OPpASSIGN_COMMON_RC1);
beb08a1e 1122 bool copy_all = FALSE;
a5f48505
DM
1123
1124 assert(!PL_in_clean_all); /* SVf_BREAK not already in use */
1125 assert(firstlelem < lastlelem); /* at least 2 LH elements */
1126 assert(firstrelem < lastrelem); /* at least 2 RH elements */
1127
ebc643ce
DM
1128
1129 lelem = firstlelem;
a5f48505
DM
1130 /* we never have to copy the first RH element; it can't be corrupted
1131 * by assigning something to the corresponding first LH element.
1132 * So this scan does in a loop: mark LHS[N]; test RHS[N+1]
1133 */
ebc643ce 1134 relem = firstrelem + 1;
a5f48505
DM
1135
1136 for (; relem <= lastrelem; relem++) {
1137 SV *svr;
1138
1139 /* mark next LH element */
1140
1141 if (--lcount >= 0) {
1142 SV *svl = *lelem++;
1143
1144 if (UNLIKELY(!svl)) {/* skip AV alias marker */
1145 assert (lelem <= lastlelem);
1146 svl = *lelem++;
1147 lcount--;
1148 }
1149
1150 assert(svl);
beb08a1e
TC
1151 if (SvSMAGICAL(svl)) {
1152 copy_all = TRUE;
1153 }
a5f48505
DM
1154 if (SvTYPE(svl) == SVt_PVAV || SvTYPE(svl) == SVt_PVHV) {
1155 if (!marked)
1156 return;
1157 /* this LH element will consume all further args;
1158 * no need to mark any further LH elements (if any).
1159 * But we still need to scan any remaining RHS elements;
1160 * set lcount negative to distinguish from lcount == 0,
1161 * so the loop condition continues being true
1162 */
1163 lcount = -1;
1164 lelem--; /* no need to unmark this element */
1165 }
94a5f659 1166 else if (!(do_rc1 && SvREFCNT(svl) == 1) && !SvIMMORTAL(svl)) {
a5f48505
DM
1167 SvFLAGS(svl) |= SVf_BREAK;
1168 marked = TRUE;
1169 }
1170 else if (!marked) {
1171 /* don't check RH element if no SVf_BREAK flags set yet */
1172 if (!lcount)
1173 break;
1174 continue;
1175 }
1176 }
1177
1178 /* see if corresponding RH element needs copying */
1179
1180 assert(marked);
1181 svr = *relem;
1182 assert(svr);
1183
5c1db569 1184 if (UNLIKELY(SvFLAGS(svr) & (SVf_BREAK|SVs_GMG) || copy_all)) {
a5f48505 1185
ebc643ce
DM
1186#ifdef DEBUGGING
1187 if (fake) {
9ae0115f 1188 /* op_dump(PL_op); */
ebc643ce
DM
1189 Perl_croak(aTHX_
1190 "panic: aassign skipped needed copy of common RH elem %"
1191 UVuf, (UV)(relem - firstrelem));
1192 }
1193#endif
1194
a5f48505
DM
1195 TAINT_NOT; /* Each item is independent */
1196
1197 /* Dear TODO test in t/op/sort.t, I love you.
1198 (It's relying on a panic, not a "semi-panic" from newSVsv()
1199 and then an assertion failure below.) */
1200 if (UNLIKELY(SvIS_FREED(svr))) {
1201 Perl_croak(aTHX_ "panic: attempt to copy freed scalar %p",
1202 (void*)svr);
1203 }
1204 /* avoid break flag while copying; otherwise COW etc
1205 * disabled... */
1206 SvFLAGS(svr) &= ~SVf_BREAK;
1207 /* Not newSVsv(), as it does not allow copy-on-write,
8c1e192f
DM
1208 resulting in wasteful copies.
1209 Also, we use SV_NOSTEAL in case the SV is used more than
1210 once, e.g. (...) = (f())[0,0]
1211 Where the same SV appears twice on the RHS without a ref
1212 count bump. (Although I suspect that the SV won't be
1213 stealable here anyway - DAPM).
1214 */
a5f48505
DM
1215 *relem = sv_mortalcopy_flags(svr,
1216 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
1217 /* ... but restore afterwards in case it's needed again,
1218 * e.g. ($a,$b,$c) = (1,$a,$a)
1219 */
1220 SvFLAGS(svr) |= SVf_BREAK;
1221 }
1222
1223 if (!lcount)
1224 break;
1225 }
1226
1227 if (!marked)
1228 return;
1229
1230 /*unmark LHS */
1231
1232 while (lelem > firstlelem) {
1233 SV * const svl = *(--lelem);
1234 if (svl)
1235 SvFLAGS(svl) &= ~SVf_BREAK;
1236 }
1237}
1238
1239
1240
a0d0e21e
LW
1241PP(pp_aassign)
1242{
27da23d5 1243 dVAR; dSP;
3280af22
NIS
1244 SV **lastlelem = PL_stack_sp;
1245 SV **lastrelem = PL_stack_base + POPMARK;
1246 SV **firstrelem = PL_stack_base + POPMARK + 1;
a0d0e21e
LW
1247 SV **firstlelem = lastrelem + 1;
1248
eb578fdb
KW
1249 SV **relem;
1250 SV **lelem;
1c23e2bd 1251 U8 gimme;
a68090fe
DM
1252 /* PL_delaymagic is restored by JUMPENV_POP on dieing, so we
1253 * only need to save locally, not on the save stack */
1254 U16 old_delaymagic = PL_delaymagic;
ebc643ce
DM
1255#ifdef DEBUGGING
1256 bool fake = 0;
1257#endif
5637b936 1258
3280af22 1259 PL_delaymagic = DM_DELAY; /* catch simultaneous items */
a0d0e21e
LW
1260
1261 /* If there's a common identifier on both sides we have to take
1262 * special care that assigning the identifier on the left doesn't
1263 * clobber a value on the right that's used later in the list.
1264 */
acdea6f0 1265
beb08a1e
TC
1266 /* at least 2 LH and RH elements, or commonality isn't an issue */
1267 if (firstlelem < lastlelem && firstrelem < lastrelem) {
5c1db569
TC
1268 for (relem = firstrelem+1; relem <= lastrelem; relem++) {
1269 if (SvGMAGICAL(*relem))
1270 goto do_scan;
1271 }
beb08a1e
TC
1272 for (lelem = firstlelem; lelem <= lastlelem; lelem++) {
1273 if (*lelem && SvSMAGICAL(*lelem))
1274 goto do_scan;
a5f48505 1275 }
beb08a1e
TC
1276 if ( PL_op->op_private & (OPpASSIGN_COMMON_SCALAR|OPpASSIGN_COMMON_RC1) ) {
1277 if (PL_op->op_private & OPpASSIGN_COMMON_RC1) {
1278 /* skip the scan if all scalars have a ref count of 1 */
1279 for (lelem = firstlelem; lelem <= lastlelem; lelem++) {
8b0c3377 1280 SV *sv = *lelem;
beb08a1e
TC
1281 if (!sv || SvREFCNT(sv) == 1)
1282 continue;
1283 if (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVAV)
1284 goto do_scan;
1285 break;
1286 }
1287 }
1288 else {
1289 do_scan:
1290 S_aassign_copy_common(aTHX_
1291 firstlelem, lastlelem, firstrelem, lastrelem
ebc643ce 1292#ifdef DEBUGGING
beb08a1e 1293 , fake
ebc643ce 1294#endif
beb08a1e
TC
1295 );
1296 }
a5f48505 1297 }
a0d0e21e 1298 }
ebc643ce
DM
1299#ifdef DEBUGGING
1300 else {
1301 /* on debugging builds, do the scan even if we've concluded we
1302 * don't need to, then panic if we find commonality. Note that the
1303 * scanner assumes at least 2 elements */
1304 if (firstlelem < lastlelem && firstrelem < lastrelem) {
1305 fake = 1;
1306 goto do_scan;
1307 }
1308 }
1309#endif
a0d0e21e 1310
a5f48505 1311 gimme = GIMME_V;
a0d0e21e
LW
1312 relem = firstrelem;
1313 lelem = firstlelem;
10c8fecd 1314
8b0c3377
DM
1315 if (relem > lastrelem)
1316 goto no_relems;
1317
1318 /* first lelem loop while there are still relems */
5d9574c1 1319 while (LIKELY(lelem <= lastlelem)) {
bdaf10a5 1320 bool alias = FALSE;
8b0c3377
DM
1321 SV *lsv = *lelem++;
1322
c73f612f
DM
1323 TAINT_NOT; /* Each item stands on its own, taintwise. */
1324
8b0c3377
DM
1325 assert(relem <= lastrelem);
1326 if (UNLIKELY(!lsv)) {
bdaf10a5 1327 alias = TRUE;
8b0c3377
DM
1328 lsv = *lelem++;
1329 ASSUME(SvTYPE(lsv) == SVt_PVAV);
bdaf10a5 1330 }
a5f48505 1331
8b0c3377
DM
1332 switch (SvTYPE(lsv)) {
1333 case SVt_PVAV: {
1334 SV **svp;
1335 SSize_t i;
1336 SSize_t tmps_base;
1337 SSize_t nelems = lastrelem - relem + 1;
b09ed995 1338 AV *ary = MUTABLE_AV(lsv);
8b0c3377
DM
1339
1340 /* Assigning to an aggregate is tricky. First there is the
1341 * issue of commonality, e.g. @a = ($a[0]). Since the
1342 * stack isn't refcounted, clearing @a prior to storing
1343 * elements will free $a[0]. Similarly with
1344 * sub FETCH { $status[$_[1]] } @status = @tied[0,1];
1345 *
1346 * The way to avoid these issues is to make the copy of each
1347 * SV (and we normally store a *copy* in the array) *before*
1348 * clearing the array. But this has a problem in that
1349 * if the code croaks during copying, the not-yet-stored copies
1350 * could leak. One way to avoid this is to make all the copies
1351 * mortal, but that's quite expensive.
1352 *
1353 * The current solution to these issues is to use a chunk
1354 * of the tmps stack as a temporary refcounted-stack. SVs
1355 * will be put on there during processing to avoid leaks,
1356 * but will be removed again before the end of this block,
1357 * so free_tmps() is never normally called. Also, the
1358 * sv_refcnt of the SVs doesn't have to be manipulated, since
1359 * the ownership of 1 reference count is transferred directly
1360 * from the tmps stack to the AV when the SV is stored.
1361 *
1362 * We disarm slots in the temps stack by storing PL_sv_undef
1363 * there: it doesn't matter if that SV's refcount is
1364 * repeatedly decremented during a croak. But usually this is
1365 * only an interim measure. By the end of this code block
1366 * we try where possible to not leave any PL_sv_undef's on the
1367 * tmps stack e.g. by shuffling newer entries down.
1368 *
1369 * There is one case where we don't copy: non-magical
1370 * SvTEMP(sv)'s with a ref count of 1. The only owner of these
1371 * is on the tmps stack, so its safe to directly steal the SV
1372 * rather than copying. This is common in things like function
1373 * returns, map etc, which all return a list of such SVs.
1374 *
1375 * Note however something like @a = (f())[0,0], where there is
1376 * a danger of the same SV being shared: this avoided because
1377 * when the SV is stored as $a[0], its ref count gets bumped,
1378 * so the RC==1 test fails and the second element is copied
1379 * instead.
1380 *
1381 * We also use one slot in the tmps stack to hold an extra
1382 * ref to the array, to ensure it doesn't get prematurely
1383 * freed. Again, this is removed before the end of this block.
1384 *
1385 * Note that OPpASSIGN_COMMON_AGG is used to flag a possible
1386 * @a = ($a[0]) case, but the current implementation uses the
1387 * same algorithm regardless, so ignores that flag. (It *is*
1388 * used in the hash branch below, however).
1389 */
1390
1391 /* Reserve slots for ary, plus the elems we're about to copy,
1392 * then protect ary and temporarily void the remaining slots
1393 * with &PL_sv_undef */
1394 EXTEND_MORTAL(nelems + 1);
1395 PL_tmps_stack[++PL_tmps_ix] = SvREFCNT_inc_simple_NN(ary);
1396 tmps_base = PL_tmps_ix + 1;
1397 for (i = 0; i < nelems; i++)
1398 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
1399 PL_tmps_ix += nelems;
1400
1401 /* Make a copy of each RHS elem and save on the tmps_stack
1402 * (or pass through where we can optimise away the copy) */
1403
1404 if (UNLIKELY(alias)) {
1405 U32 lval = (gimme == G_ARRAY)
1406 ? (PL_op->op_flags & OPf_MOD || LVRET) : 0;
a5f48505 1407 for (svp = relem; svp <= lastrelem; svp++) {
8b0c3377
DM
1408 SV *rsv = *svp;
1409
1410 SvGETMAGIC(rsv);
1411 if (!SvROK(rsv))
1412 DIE(aTHX_ "Assigned value is not a reference");
1413 if (SvTYPE(SvRV(rsv)) > SVt_PVLV)
1414 /* diag_listed_as: Assigned value is not %s reference */
1415 DIE(aTHX_
1416 "Assigned value is not a SCALAR reference");
1417 if (lval)
1418 *svp = rsv = sv_mortalcopy(rsv);
1419 /* XXX else check for weak refs? */
1420 rsv = SvREFCNT_inc_NN(SvRV(rsv));
1421 assert(tmps_base <= PL_tmps_max);
1422 PL_tmps_stack[tmps_base++] = rsv;
a5f48505 1423 }
a5f48505 1424 }
8b0c3377
DM
1425 else {
1426 for (svp = relem; svp <= lastrelem; svp++) {
1427 SV *rsv = *svp;
a5f48505 1428
8b0c3377
DM
1429 if (SvTEMP(rsv) && !SvGMAGICAL(rsv) && SvREFCNT(rsv) == 1) {
1430 /* can skip the copy */
1431 SvREFCNT_inc_simple_void_NN(rsv);
1432 SvTEMP_off(rsv);
1433 }
a5f48505 1434 else {
8b0c3377
DM
1435 SV *nsv;
1436 /* do get before newSV, in case it dies and leaks */
1437 SvGETMAGIC(rsv);
1438 nsv = newSV(0);
8c1e192f
DM
1439 /* see comment in S_aassign_copy_common about
1440 * SV_NOSTEAL */
8b0c3377
DM
1441 sv_setsv_flags(nsv, rsv,
1442 (SV_DO_COW_SVSETSV|SV_NOSTEAL));
1443 rsv = *svp = nsv;
a5f48505 1444 }
8b0c3377
DM
1445
1446 assert(tmps_base <= PL_tmps_max);
1447 PL_tmps_stack[tmps_base++] = rsv;
1448 }
1449 }
1450
1451 if (SvRMAGICAL(ary) || AvFILLp(ary) >= 0) /* may be non-empty */
1452 av_clear(ary);
1453
1454 /* store in the array, the SVs that are in the tmps stack */
1455
1456 tmps_base -= nelems;
1457
80c1439f 1458 if (SvMAGICAL(ary) || SvREADONLY(ary) || !AvREAL(ary)) {
8b0c3377
DM
1459 /* for arrays we can't cheat with, use the official API */
1460 av_extend(ary, nelems - 1);
1461 for (i = 0; i < nelems; i++) {
1462 SV **svp = &(PL_tmps_stack[tmps_base + i]);
1463 SV *rsv = *svp;
1464 /* A tied store won't take ownership of rsv, so keep
1465 * the 1 refcnt on the tmps stack; otherwise disarm
1466 * the tmps stack entry */
1467 if (av_store(ary, i, rsv))
1468 *svp = &PL_sv_undef;
1469 /* av_store() may have added set magic to rsv */;
1470 SvSETMAGIC(rsv);
1471 }
1472 /* disarm ary refcount: see comments below about leak */
1473 PL_tmps_stack[tmps_base - 1] = &PL_sv_undef;
1474 }
1475 else {
1476 /* directly access/set the guts of the AV */
1477 SSize_t fill = nelems - 1;
1478 if (fill > AvMAX(ary))
1479 av_extend_guts(ary, fill, &AvMAX(ary), &AvALLOC(ary),
1480 &AvARRAY(ary));
1481 AvFILLp(ary) = fill;
1482 Copy(&(PL_tmps_stack[tmps_base]), AvARRAY(ary), nelems, SV*);
1483 /* Quietly remove all the SVs from the tmps stack slots,
1484 * since ary has now taken ownership of the refcnt.
1485 * Also remove ary: which will now leak if we die before
1486 * the SvREFCNT_dec_NN(ary) below */
1487 if (UNLIKELY(PL_tmps_ix >= tmps_base + nelems))
1488 Move(&PL_tmps_stack[tmps_base + nelems],
1489 &PL_tmps_stack[tmps_base - 1],
1490 PL_tmps_ix - (tmps_base + nelems) + 1,
1491 SV*);
1492 PL_tmps_ix -= (nelems + 1);
1493 }
1494
5d9574c1 1495 if (UNLIKELY(PL_delaymagic & DM_ARRAY_ISA))
8b0c3377 1496 /* its assumed @ISA set magic can't die and leak ary */
ad64d0ec 1497 SvSETMAGIC(MUTABLE_SV(ary));
8b0c3377
DM
1498 SvREFCNT_dec_NN(ary);
1499
1500 relem = lastrelem + 1;
1501 goto no_relems;
a5f48505
DM
1502 }
1503
10c8fecd 1504 case SVt_PVHV: { /* normal hash */
8b0c3377
DM
1505
1506 SV **svp;
1507 bool dirty_tmps;
1508 SSize_t i;
1509 SSize_t tmps_base;
1510 SSize_t nelems = lastrelem - relem + 1;
b09ed995 1511 HV *hash = MUTABLE_HV(lsv);
8b0c3377
DM
1512
1513 if (UNLIKELY(nelems & 1)) {
1514 do_oddball(lastrelem, relem);
1515 /* we have firstlelem to reuse, it's not needed any more */
1516 *++lastrelem = &PL_sv_undef;
1517 nelems++;
1518 }
1519
1520 /* See the SVt_PVAV branch above for a long description of
1521 * how the following all works. The main difference for hashes
1522 * is that we treat keys and values separately (and have
1523 * separate loops for them): as for arrays, values are always
1524 * copied (except for the SvTEMP optimisation), since they
1525 * need to be stored in the hash; while keys are only
1526 * processed where they might get prematurely freed or
1527 * whatever. */
1528
1529 /* tmps stack slots:
1530 * * reserve a slot for the hash keepalive;
1531 * * reserve slots for the hash values we're about to copy;
1532 * * preallocate for the keys we'll possibly copy or refcount bump
1533 * later;
1534 * then protect hash and temporarily void the remaining
1535 * value slots with &PL_sv_undef */
1536 EXTEND_MORTAL(nelems + 1);
1537
1538 /* convert to number of key/value pairs */
1539 nelems >>= 1;
1540
1541 PL_tmps_stack[++PL_tmps_ix] = SvREFCNT_inc_simple_NN(hash);
1542 tmps_base = PL_tmps_ix + 1;
1543 for (i = 0; i < nelems; i++)
1544 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
1545 PL_tmps_ix += nelems;
1546
1547 /* Make a copy of each RHS hash value and save on the tmps_stack
1548 * (or pass through where we can optimise away the copy) */
1549
1550 for (svp = relem + 1; svp <= lastrelem; svp += 2) {
1551 SV *rsv = *svp;
1552
1553 if (SvTEMP(rsv) && !SvGMAGICAL(rsv) && SvREFCNT(rsv) == 1) {
1554 /* can skip the copy */
1555 SvREFCNT_inc_simple_void_NN(rsv);
1556 SvTEMP_off(rsv);
1557 }
1558 else {
1559 SV *nsv;
1560 /* do get before newSV, in case it dies and leaks */
1561 SvGETMAGIC(rsv);
1562 nsv = newSV(0);
1563 /* see comment in S_aassign_copy_common about
1564 * SV_NOSTEAL */
1565 sv_setsv_flags(nsv, rsv,
1566 (SV_DO_COW_SVSETSV|SV_NOSTEAL));
1567 rsv = *svp = nsv;
1c4ea384
RZ
1568 }
1569
8b0c3377
DM
1570 assert(tmps_base <= PL_tmps_max);
1571 PL_tmps_stack[tmps_base++] = rsv;
1572 }
1573 tmps_base -= nelems;
a5f48505 1574
a5f48505 1575
8b0c3377
DM
1576 /* possibly protect keys */
1577
1578 if (UNLIKELY(gimme == G_ARRAY)) {
1579 /* handle e.g.
1580 * @a = ((%h = ($$r, 1)), $r = "x");
1581 * $_++ for %h = (1,2,3,4);
1582 */
1583 EXTEND_MORTAL(nelems);
1584 for (svp = relem; svp <= lastrelem; svp += 2)
1585 *svp = sv_mortalcopy_flags(*svp,
1586 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
1587 }
1588 else if (PL_op->op_private & OPpASSIGN_COMMON_AGG) {
1589 /* for possible commonality, e.g.
1590 * %h = ($h{a},1)
1591 * avoid premature freeing RHS keys by mortalising
1592 * them.
1593 * For a magic element, make a copy so that its magic is
1594 * called *before* the hash is emptied (which may affect
1595 * a tied value for example).
1596 * In theory we should check for magic keys in all
1597 * cases, not just under OPpASSIGN_COMMON_AGG, but in
1598 * practice, !OPpASSIGN_COMMON_AGG implies only
1599 * constants or padtmps on the RHS.
1600 */
1601 EXTEND_MORTAL(nelems);
1602 for (svp = relem; svp <= lastrelem; svp += 2) {
1603 SV *rsv = *svp;
1604 if (UNLIKELY(SvGMAGICAL(rsv))) {
1605 SSize_t n;
a5f48505
DM
1606 *svp = sv_mortalcopy_flags(*svp,
1607 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
8b0c3377
DM
1608 /* allow other branch to continue pushing
1609 * onto tmps stack without checking each time */
1610 n = (lastrelem - relem) >> 1;
1611 EXTEND_MORTAL(n);
a5f48505 1612 }
8b0c3377
DM
1613 else
1614 PL_tmps_stack[++PL_tmps_ix] =
1615 SvREFCNT_inc_simple_NN(rsv);
a5f48505 1616 }
8b0c3377 1617 }
a5f48505 1618
8b0c3377
DM
1619 if (SvRMAGICAL(hash) || HvUSEDKEYS(hash))
1620 hv_clear(hash);
a5f48505 1621
8b0c3377
DM
1622 /* now assign the keys and values to the hash */
1623
1624 dirty_tmps = FALSE;
1625
1626 if (UNLIKELY(gimme == G_ARRAY)) {
1627 /* @a = (%h = (...)) etc */
1628 SV **svp;
1629 SV **topelem = relem;
1630
1631 for (i = 0, svp = relem; svp <= lastrelem; i++, svp++) {
1632 SV *key = *svp++;
1633 SV *val = *svp;
1634 /* remove duplicates from list we return */
1635 if (!hv_exists_ent(hash, key, 0)) {
1636 /* copy key back: possibly to an earlier
1637 * stack location if we encountered dups earlier,
1638 * The values will be updated later
1639 */
1640 *topelem = key;
1641 topelem += 2;
632b9d6f 1642 }
8b0c3377
DM
1643 /* A tied store won't take ownership of val, so keep
1644 * the 1 refcnt on the tmps stack; otherwise disarm
1645 * the tmps stack entry */
1646 if (hv_store_ent(hash, key, val, 0))
1647 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
1648 else
1649 dirty_tmps = TRUE;
1650 /* hv_store_ent() may have added set magic to val */;
1651 SvSETMAGIC(val);
1652 }
1653 if (topelem < svp) {
1c4ea384
RZ
1654 /* at this point we have removed the duplicate key/value
1655 * pairs from the stack, but the remaining values may be
1656 * wrong; i.e. with (a 1 a 2 b 3) on the stack we've removed
1657 * the (a 2), but the stack now probably contains
1658 * (a <freed> b 3), because { hv_save(a,1); hv_save(a,2) }
1659 * obliterates the earlier key. So refresh all values. */
8b0c3377
DM
1660 lastrelem = topelem - 1;
1661 while (relem < lastrelem) {
1c4ea384
RZ
1662 HE *he;
1663 he = hv_fetch_ent(hash, *relem++, 0, 0);
1664 *relem++ = (he ? HeVAL(he) : &PL_sv_undef);
1665 }
1666 }
8b0c3377
DM
1667 }
1668 else {
1669 SV **svp;
1670 for (i = 0, svp = relem; svp <= lastrelem; i++, svp++) {
1671 SV *key = *svp++;
1672 SV *val = *svp;
1673 if (hv_store_ent(hash, key, val, 0))
1674 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
1675 else
1676 dirty_tmps = TRUE;
1677 /* hv_store_ent() may have added set magic to val */;
1678 SvSETMAGIC(val);
1679 }
1680 }
1681
1682 if (dirty_tmps) {
1683 /* there are still some 'live' recounts on the tmps stack
1684 * - usually caused by storing into a tied hash. So let
1685 * free_tmps() do the proper but slow job later.
1686 * Just disarm hash refcount: see comments below about leak
1687 */
1688 PL_tmps_stack[tmps_base - 1] = &PL_sv_undef;
1689 }
1690 else {
1691 /* Quietly remove all the SVs from the tmps stack slots,
1692 * since hash has now taken ownership of the refcnt.
1693 * Also remove hash: which will now leak if we die before
1694 * the SvREFCNT_dec_NN(hash) below */
1695 if (UNLIKELY(PL_tmps_ix >= tmps_base + nelems))
1696 Move(&PL_tmps_stack[tmps_base + nelems],
1697 &PL_tmps_stack[tmps_base - 1],
1698 PL_tmps_ix - (tmps_base + nelems) + 1,
1699 SV*);
1700 PL_tmps_ix -= (nelems + 1);
1701 }
1702
1703 SvREFCNT_dec_NN(hash);
1704
1705 relem = lastrelem + 1;
1706 goto no_relems;
1707 }
1708
a0d0e21e 1709 default:
8b0c3377 1710 if (!SvIMMORTAL(lsv)) {
d24e3eb1
DM
1711 SV *ref;
1712
8b0c3377
DM
1713 if (UNLIKELY(
1714 SvTEMP(lsv) && !SvSMAGICAL(lsv) && SvREFCNT(lsv) == 1 &&
1715 (!isGV_with_GP(lsv) || SvFAKE(lsv)) && ckWARN(WARN_MISC)
1716 ))
1717 Perl_warner(aTHX_
1718 packWARN(WARN_MISC),
1719 "Useless assignment to a temporary"
1720 );
d24e3eb1
DM
1721
1722 /* avoid freeing $$lsv if it might be needed for further
1723 * elements, e.g. ($ref, $foo) = (1, $$ref) */
1724 if ( SvROK(lsv)
1725 && ( ((ref = SvRV(lsv)), SvREFCNT(ref)) == 1)
1726 && lelem <= lastlelem
1727 ) {
1728 SSize_t ix;
1729 SvREFCNT_inc_simple_void_NN(ref);
1730 /* an unrolled sv_2mortal */
1731 ix = ++PL_tmps_ix;
1732 if (UNLIKELY(ix >= PL_tmps_max))
1733 /* speculatively grow enough to cover other
1734 * possible refs */
1735 ix = tmps_grow_p(ix + (lastlelem - lelem));
1736 PL_tmps_stack[ix] = ref;
1737 }
1738
8b0c3377
DM
1739 sv_setsv(lsv, *relem);
1740 *relem = lsv;
1741 SvSETMAGIC(lsv);
1742 }
1743 if (++relem > lastrelem)
1744 goto no_relems;
a0d0e21e 1745 break;
8b0c3377
DM
1746 } /* switch */
1747 } /* while */
1748
1749
1750 no_relems:
1751
1752 /* simplified lelem loop for when there are no relems left */
1753 while (LIKELY(lelem <= lastlelem)) {
1754 SV *lsv = *lelem++;
c73f612f
DM
1755
1756 TAINT_NOT; /* Each item stands on its own, taintwise. */
1757
8b0c3377
DM
1758 if (UNLIKELY(!lsv)) {
1759 lsv = *lelem++;
1760 ASSUME(SvTYPE(lsv) == SVt_PVAV);
a0d0e21e 1761 }
8b0c3377
DM
1762
1763 switch (SvTYPE(lsv)) {
1764 case SVt_PVAV:
b09ed995
DM
1765 if (SvRMAGICAL(lsv) || AvFILLp((SV*)lsv) >= 0) {
1766 av_clear((AV*)lsv);
8b0c3377 1767 if (UNLIKELY(PL_delaymagic & DM_ARRAY_ISA))
b09ed995 1768 SvSETMAGIC(lsv);
8b0c3377
DM
1769 }
1770 break;
1771
1772 case SVt_PVHV:
b09ed995
DM
1773 if (SvRMAGICAL(lsv) || HvUSEDKEYS((HV*)lsv))
1774 hv_clear((HV*)lsv);
8b0c3377
DM
1775 break;
1776
1777 default:
1778 if (!SvIMMORTAL(lsv)) {
e03e82a0 1779 sv_set_undef(lsv);
8b0c3377 1780 SvSETMAGIC(lsv);
b09ed995 1781 *relem++ = lsv;
8b0c3377
DM
1782 }
1783 break;
1784 } /* switch */
1785 } /* while */
1786
c73f612f
DM
1787 TAINT_NOT; /* result of list assign isn't tainted */
1788
5d9574c1 1789 if (UNLIKELY(PL_delaymagic & ~DM_DELAY)) {
985213f2 1790 /* Will be used to set PL_tainting below */
dfff4baf
BF
1791 Uid_t tmp_uid = PerlProc_getuid();
1792 Uid_t tmp_euid = PerlProc_geteuid();
1793 Gid_t tmp_gid = PerlProc_getgid();
1794 Gid_t tmp_egid = PerlProc_getegid();
985213f2 1795
b469f1e0 1796 /* XXX $> et al currently silently ignore failures */
3280af22 1797 if (PL_delaymagic & DM_UID) {
a0d0e21e 1798#ifdef HAS_SETRESUID
b469f1e0
JH
1799 PERL_UNUSED_RESULT(
1800 setresuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
1801 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1,
1802 (Uid_t)-1));
56febc5e
AD
1803#else
1804# ifdef HAS_SETREUID
b469f1e0
JH
1805 PERL_UNUSED_RESULT(
1806 setreuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
1807 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1));
56febc5e
AD
1808# else
1809# ifdef HAS_SETRUID
b28d0864 1810 if ((PL_delaymagic & DM_UID) == DM_RUID) {
b469f1e0 1811 PERL_UNUSED_RESULT(setruid(PL_delaymagic_uid));
b28d0864 1812 PL_delaymagic &= ~DM_RUID;
a0d0e21e 1813 }
56febc5e
AD
1814# endif /* HAS_SETRUID */
1815# ifdef HAS_SETEUID
b28d0864 1816 if ((PL_delaymagic & DM_UID) == DM_EUID) {
b469f1e0 1817 PERL_UNUSED_RESULT(seteuid(PL_delaymagic_euid));
b28d0864 1818 PL_delaymagic &= ~DM_EUID;
a0d0e21e 1819 }
56febc5e 1820# endif /* HAS_SETEUID */
b28d0864 1821 if (PL_delaymagic & DM_UID) {
985213f2 1822 if (PL_delaymagic_uid != PL_delaymagic_euid)
cea2e8a9 1823 DIE(aTHX_ "No setreuid available");
b469f1e0 1824 PERL_UNUSED_RESULT(PerlProc_setuid(PL_delaymagic_uid));
a0d0e21e 1825 }
56febc5e
AD
1826# endif /* HAS_SETREUID */
1827#endif /* HAS_SETRESUID */
04783dc7 1828
985213f2
AB
1829 tmp_uid = PerlProc_getuid();
1830 tmp_euid = PerlProc_geteuid();
a0d0e21e 1831 }
b469f1e0 1832 /* XXX $> et al currently silently ignore failures */
3280af22 1833 if (PL_delaymagic & DM_GID) {
a0d0e21e 1834#ifdef HAS_SETRESGID
b469f1e0
JH
1835 PERL_UNUSED_RESULT(
1836 setresgid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
1837 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1,
1838 (Gid_t)-1));
56febc5e
AD
1839#else
1840# ifdef HAS_SETREGID
b469f1e0
JH
1841 PERL_UNUSED_RESULT(
1842 setregid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
1843 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1));
56febc5e
AD
1844# else
1845# ifdef HAS_SETRGID
b28d0864 1846 if ((PL_delaymagic & DM_GID) == DM_RGID) {
b469f1e0 1847 PERL_UNUSED_RESULT(setrgid(PL_delaymagic_gid));
b28d0864 1848 PL_delaymagic &= ~DM_RGID;
a0d0e21e 1849 }
56febc5e
AD
1850# endif /* HAS_SETRGID */
1851# ifdef HAS_SETEGID
b28d0864 1852 if ((PL_delaymagic & DM_GID) == DM_EGID) {
b469f1e0 1853 PERL_UNUSED_RESULT(setegid(PL_delaymagic_egid));
b28d0864 1854 PL_delaymagic &= ~DM_EGID;
a0d0e21e 1855 }
56febc5e 1856# endif /* HAS_SETEGID */
b28d0864 1857 if (PL_delaymagic & DM_GID) {
985213f2 1858 if (PL_delaymagic_gid != PL_delaymagic_egid)
cea2e8a9 1859 DIE(aTHX_ "No setregid available");
b469f1e0 1860 PERL_UNUSED_RESULT(PerlProc_setgid(PL_delaymagic_gid));
a0d0e21e 1861 }
56febc5e
AD
1862# endif /* HAS_SETREGID */
1863#endif /* HAS_SETRESGID */
04783dc7 1864
985213f2
AB
1865 tmp_gid = PerlProc_getgid();
1866 tmp_egid = PerlProc_getegid();
a0d0e21e 1867 }
284167a5 1868 TAINTING_set( TAINTING_get | (tmp_uid && (tmp_euid != tmp_uid || tmp_egid != tmp_gid)) );
9a9b5ec9
DM
1869#ifdef NO_TAINT_SUPPORT
1870 PERL_UNUSED_VAR(tmp_uid);
1871 PERL_UNUSED_VAR(tmp_euid);
1872 PERL_UNUSED_VAR(tmp_gid);
1873 PERL_UNUSED_VAR(tmp_egid);
1874#endif
a0d0e21e 1875 }
a68090fe 1876 PL_delaymagic = old_delaymagic;
54310121 1877
54310121
PP
1878 if (gimme == G_VOID)
1879 SP = firstrelem - 1;
1880 else if (gimme == G_SCALAR) {
1881 dTARGET;
1882 SP = firstrelem;
b09ed995 1883 EXTEND(SP,1);
8b0c3377 1884 SETi(firstlelem - firstrelem);
54310121 1885 }
b09ed995
DM
1886 else
1887 SP = relem - 1;
08aeb9f7 1888
54310121 1889 RETURN;
a0d0e21e
LW
1890}
1891
8782bef2
GB
1892PP(pp_qr)
1893{
20b7effb 1894 dSP;
eb578fdb 1895 PMOP * const pm = cPMOP;
fe578d7f 1896 REGEXP * rx = PM_GETRE(pm);
10599a69 1897 SV * const pkg = rx ? CALLREG_PACKAGE(rx) : NULL;
c4420975 1898 SV * const rv = sv_newmortal();
d63c20f2
DM
1899 CV **cvp;
1900 CV *cv;
288b8c02
NC
1901
1902 SvUPGRADE(rv, SVt_IV);
c2123ae3
NC
1903 /* For a subroutine describing itself as "This is a hacky workaround" I'm
1904 loathe to use it here, but it seems to be the right fix. Or close.
1905 The key part appears to be that it's essential for pp_qr to return a new
1906 object (SV), which implies that there needs to be an effective way to
1907 generate a new SV from the existing SV that is pre-compiled in the
1908 optree. */
1909 SvRV_set(rv, MUTABLE_SV(reg_temp_copy(NULL, rx)));
288b8c02
NC
1910 SvROK_on(rv);
1911
8d919b0a 1912 cvp = &( ReANY((REGEXP *)SvRV(rv))->qr_anoncv);
5d9574c1 1913 if (UNLIKELY((cv = *cvp) && CvCLONE(*cvp))) {
d63c20f2 1914 *cvp = cv_clone(cv);
fc2b2dca 1915 SvREFCNT_dec_NN(cv);
d63c20f2
DM
1916 }
1917
288b8c02 1918 if (pkg) {
f815daf2 1919 HV *const stash = gv_stashsv(pkg, GV_ADD);
fc2b2dca 1920 SvREFCNT_dec_NN(pkg);
288b8c02
NC
1921 (void)sv_bless(rv, stash);
1922 }
1923
5d9574c1 1924 if (UNLIKELY(RX_ISTAINTED(rx))) {
e08e52cf 1925 SvTAINTED_on(rv);
9274aefd
DM
1926 SvTAINTED_on(SvRV(rv));
1927 }
c8c13c22 1928 XPUSHs(rv);
1929 RETURN;
8782bef2
GB
1930}
1931
a0d0e21e
LW
1932PP(pp_match)
1933{
20b7effb 1934 dSP; dTARG;
eb578fdb 1935 PMOP *pm = cPMOP;
d65afb4b 1936 PMOP *dynpm = pm;
eb578fdb 1937 const char *s;
5c144d81 1938 const char *strend;
99a90e59 1939 SSize_t curpos = 0; /* initial pos() or current $+[0] */
a0d0e21e 1940 I32 global;
7fadf4a7 1941 U8 r_flags = 0;
5c144d81 1942 const char *truebase; /* Start of string */
eb578fdb 1943 REGEXP *rx = PM_GETRE(pm);
b3eb6a9b 1944 bool rxtainted;
1c23e2bd 1945 const U8 gimme = GIMME_V;
a0d0e21e 1946 STRLEN len;
a3b680e6 1947 const I32 oldsave = PL_savestack_ix;
e60df1fa 1948 I32 had_zerolen = 0;
b1422d62 1949 MAGIC *mg = NULL;
a0d0e21e 1950
533c011a 1951 if (PL_op->op_flags & OPf_STACKED)
a0d0e21e 1952 TARG = POPs;
6ffceeb7 1953 else if (ARGTARG)
59f00321 1954 GETTARGET;
a0d0e21e 1955 else {
54b9620d 1956 TARG = DEFSV;
a0d0e21e
LW
1957 EXTEND(SP,1);
1958 }
d9f424b2 1959
c277df42 1960 PUTBACK; /* EVAL blocks need stack_sp. */
69dc4b30
FC
1961 /* Skip get-magic if this is a qr// clone, because regcomp has
1962 already done it. */
f1d31338 1963 truebase = ReANY(rx)->mother_re
69dc4b30
FC
1964 ? SvPV_nomg_const(TARG, len)
1965 : SvPV_const(TARG, len);
f1d31338 1966 if (!truebase)
2269b42e 1967 DIE(aTHX_ "panic: pp_match");
f1d31338 1968 strend = truebase + len;
284167a5
SM
1969 rxtainted = (RX_ISTAINTED(rx) ||
1970 (TAINT_get && (pm->op_pmflags & PMf_RETAINT)));
9212bbba 1971 TAINT_NOT;
a0d0e21e 1972
6c864ec2 1973 /* We need to know this in case we fail out early - pos() must be reset */
de0df3c0
MH
1974 global = dynpm->op_pmflags & PMf_GLOBAL;
1975
d65afb4b 1976 /* PMdf_USED is set after a ?? matches once */
c737faaf
YO
1977 if (
1978#ifdef USE_ITHREADS
1979 SvREADONLY(PL_regex_pad[pm->op_pmoffset])
1980#else
1981 pm->op_pmflags & PMf_USED
1982#endif
1983 ) {
e5dc5375 1984 DEBUG_r(PerlIO_printf(Perl_debug_log, "?? already matched once"));
de0df3c0 1985 goto nope;
a0d0e21e
LW
1986 }
1987
5585e758
YO
1988 /* handle the empty pattern */
1989 if (!RX_PRELEN(rx) && PL_curpm && !ReANY(rx)->mother_re) {
1990 if (PL_curpm == PL_reg_curpm) {
1991 if (PL_curpm_under) {
1992 if (PL_curpm_under == PL_reg_curpm) {
1993 Perl_croak(aTHX_ "Infinite recursion via empty pattern");
1994 } else {
1995 pm = PL_curpm_under;
1996 }
1997 }
1998 } else {
1999 pm = PL_curpm;
2000 }
2001 rx = PM_GETRE(pm);
a0d0e21e 2002 }
d65afb4b 2003
389ecb56 2004 if (RX_MINLEN(rx) >= 0 && (STRLEN)RX_MINLEN(rx) > len) {
75d43e96 2005 DEBUG_r(PerlIO_printf(Perl_debug_log, "String shorter than min possible regex match (%"
147e3846 2006 UVuf " < %" IVdf ")\n",
75d43e96 2007 (UV)len, (IV)RX_MINLEN(rx)));
de0df3c0 2008 goto nope;
e5dc5375 2009 }
c277df42 2010
8ef97b0e 2011 /* get pos() if //g */
de0df3c0 2012 if (global) {
b1422d62 2013 mg = mg_find_mglob(TARG);
8ef97b0e 2014 if (mg && mg->mg_len >= 0) {
25fdce4a 2015 curpos = MgBYTEPOS(mg, TARG, truebase, len);
8ef97b0e
DM
2016 /* last time pos() was set, it was zero-length match */
2017 if (mg->mg_flags & MGf_MINMATCH)
2018 had_zerolen = 1;
2019 }
a0d0e21e 2020 }
8ef97b0e 2021
6e240d0b 2022#ifdef PERL_SAWAMPERSAND
a41aa44d 2023 if ( RX_NPARENS(rx)
6502e081 2024 || PL_sawampersand
6502e081 2025 || (RX_EXTFLAGS(rx) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
5b0e71e9 2026 || (dynpm->op_pmflags & PMf_KEEPCOPY)
6e240d0b
FC
2027 )
2028#endif
2029 {
6502e081
DM
2030 r_flags |= (REXEC_COPY_STR|REXEC_COPY_SKIP_PRE);
2031 /* in @a =~ /(.)/g, we iterate multiple times, but copy the buffer
2032 * only on the first iteration. Therefore we need to copy $' as well
2033 * as $&, to make the rest of the string available for captures in
2034 * subsequent iterations */
2035 if (! (global && gimme == G_ARRAY))
2036 r_flags |= REXEC_COPY_SKIP_POST;
2037 };
5b0e71e9
DM
2038#ifdef PERL_SAWAMPERSAND
2039 if (dynpm->op_pmflags & PMf_KEEPCOPY)
2040 /* handle KEEPCOPY in pmop but not rx, eg $r=qr/a/; /$r/p */
2041 r_flags &= ~(REXEC_COPY_SKIP_PRE|REXEC_COPY_SKIP_POST);
2042#endif
22e551b9 2043
f1d31338
DM
2044 s = truebase;
2045
d7be1480 2046 play_it_again:
985afbc1 2047 if (global)
03c83e26 2048 s = truebase + curpos;
f722798b 2049
77da2310 2050 if (!CALLREGEXEC(rx, (char*)s, (char *)strend, (char*)truebase,
03c83e26 2051 had_zerolen, TARG, NULL, r_flags))
03b6c93d 2052 goto nope;
77da2310
NC
2053
2054 PL_curpm = pm;
985afbc1 2055 if (dynpm->op_pmflags & PMf_ONCE)
c737faaf 2056#ifdef USE_ITHREADS
77da2310 2057 SvREADONLY_on(PL_regex_pad[dynpm->op_pmoffset]);
c737faaf 2058#else
77da2310 2059 dynpm->op_pmflags |= PMf_USED;
c737faaf 2060#endif
a0d0e21e 2061
72311751
GS
2062 if (rxtainted)
2063 RX_MATCH_TAINTED_on(rx);
2064 TAINT_IF(RX_MATCH_TAINTED(rx));
35c2ccc3
DM
2065
2066 /* update pos */
2067
2068 if (global && (gimme != G_ARRAY || (dynpm->op_pmflags & PMf_CONTINUE))) {
b1422d62 2069 if (!mg)
35c2ccc3 2070 mg = sv_magicext_mglob(TARG);
25fdce4a 2071 MgBYTEPOS_set(mg, TARG, truebase, RX_OFFS(rx)[0].end);
adf51885
DM
2072 if (RX_ZERO_LEN(rx))
2073 mg->mg_flags |= MGf_MINMATCH;
2074 else
2075 mg->mg_flags &= ~MGf_MINMATCH;
35c2ccc3
DM
2076 }
2077
bf9dff51
DM
2078 if ((!RX_NPARENS(rx) && !global) || gimme != G_ARRAY) {
2079 LEAVE_SCOPE(oldsave);
2080 RETPUSHYES;
2081 }
2082
88ab22af
DM
2083 /* push captures on stack */
2084
bf9dff51 2085 {
07bc277f 2086 const I32 nparens = RX_NPARENS(rx);
a3b680e6 2087 I32 i = (global && !nparens) ? 1 : 0;
a0d0e21e 2088
c277df42 2089 SPAGAIN; /* EVAL blocks could move the stack. */
ffc61ed2
JH
2090 EXTEND(SP, nparens + i);
2091 EXTEND_MORTAL(nparens + i);
2092 for (i = !i; i <= nparens; i++) {
a0d0e21e 2093 PUSHs(sv_newmortal());
5d9574c1
DM
2094 if (LIKELY((RX_OFFS(rx)[i].start != -1)
2095 && RX_OFFS(rx)[i].end != -1 ))
2096 {
07bc277f 2097 const I32 len = RX_OFFS(rx)[i].end - RX_OFFS(rx)[i].start;
f1d31338 2098 const char * const s = RX_OFFS(rx)[i].start + truebase;
5d9574c1
DM
2099 if (UNLIKELY(RX_OFFS(rx)[i].end < 0 || RX_OFFS(rx)[i].start < 0
2100 || len < 0 || len > strend - s))
5637ef5b 2101 DIE(aTHX_ "panic: pp_match start/end pointers, i=%ld, "
147e3846 2102 "start=%ld, end=%ld, s=%p, strend=%p, len=%" UVuf,
5637ef5b
NC
2103 (long) i, (long) RX_OFFS(rx)[i].start,
2104 (long)RX_OFFS(rx)[i].end, s, strend, (UV) len);
a0d0e21e 2105 sv_setpvn(*SP, s, len);
cce850e4 2106 if (DO_UTF8(TARG) && is_utf8_string((U8*)s, len))
a197cbdd 2107 SvUTF8_on(*SP);
a0d0e21e
LW
2108 }
2109 }
2110 if (global) {
0e0b3e82 2111 curpos = (UV)RX_OFFS(rx)[0].end;
03c83e26 2112 had_zerolen = RX_ZERO_LEN(rx);
c277df42 2113 PUTBACK; /* EVAL blocks may use stack */
cf93c79d 2114 r_flags |= REXEC_IGNOREPOS | REXEC_NOT_FIRST;
a0d0e21e
LW
2115 goto play_it_again;
2116 }
4633a7c4 2117 LEAVE_SCOPE(oldsave);
a0d0e21e
LW
2118 RETURN;
2119 }
e5964223 2120 NOT_REACHED; /* NOTREACHED */
a0d0e21e 2121
7b52d656 2122 nope:
d65afb4b 2123 if (global && !(dynpm->op_pmflags & PMf_CONTINUE)) {
b1422d62
DM
2124 if (!mg)
2125 mg = mg_find_mglob(TARG);
2126 if (mg)
2127 mg->mg_len = -1;
a0d0e21e 2128 }
4633a7c4 2129 LEAVE_SCOPE(oldsave);
a0d0e21e
LW
2130 if (gimme == G_ARRAY)
2131 RETURN;
2132 RETPUSHNO;
2133}
2134
2135OP *
864dbfa3 2136Perl_do_readline(pTHX)
a0d0e21e 2137{
20b7effb 2138 dSP; dTARGETSTACKED;
eb578fdb 2139 SV *sv;
a0d0e21e
LW
2140 STRLEN tmplen = 0;
2141 STRLEN offset;
760ac839 2142 PerlIO *fp;
eb578fdb
KW
2143 IO * const io = GvIO(PL_last_in_gv);
2144 const I32 type = PL_op->op_type;
1c23e2bd 2145 const U8 gimme = GIMME_V;
a0d0e21e 2146
6136c704 2147 if (io) {
50db69d8 2148 const MAGIC *const mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar);
6136c704 2149 if (mg) {
3e0cb5de 2150 Perl_tied_method(aTHX_ SV_CONST(READLINE), SP, MUTABLE_SV(io), mg, gimme, 0);
6136c704 2151 if (gimme == G_SCALAR) {
50db69d8
NC
2152 SPAGAIN;
2153 SvSetSV_nosteal(TARG, TOPs);
2154 SETTARG;
6136c704 2155 }
50db69d8 2156 return NORMAL;
0b7c7b4f 2157 }
e79b0511 2158 }
4608196e 2159 fp = NULL;
a0d0e21e
LW
2160 if (io) {
2161 fp = IoIFP(io);
2162 if (!fp) {
2163 if (IoFLAGS(io) & IOf_ARGV) {
2164 if (IoFLAGS(io) & IOf_START) {
a0d0e21e 2165 IoLINES(io) = 0;
b9f2b683 2166 if (av_tindex(GvAVn(PL_last_in_gv)) < 0) {
1d7c1841 2167 IoFLAGS(io) &= ~IOf_START;
d5eb9a46 2168 do_open6(PL_last_in_gv, "-", 1, NULL, NULL, 0);
4bac9ae4 2169 SvTAINTED_off(GvSVn(PL_last_in_gv)); /* previous tainting irrelevant */
76f68e9b 2170 sv_setpvs(GvSVn(PL_last_in_gv), "-");
3280af22 2171 SvSETMAGIC(GvSV(PL_last_in_gv));
a2008d6d
GS
2172 fp = IoIFP(io);
2173 goto have_fp;
a0d0e21e
LW
2174 }
2175 }
157fb5a1 2176 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
a0d0e21e 2177 if (!fp) { /* Note: fp != IoIFP(io) */
3280af22 2178 (void)do_close(PL_last_in_gv, FALSE); /* now it does*/
a0d0e21e
LW
2179 }
2180 }
0d44d22b
NC
2181 else if (type == OP_GLOB)
2182 fp = Perl_start_glob(aTHX_ POPs, io);
a0d0e21e
LW
2183 }
2184 else if (type == OP_GLOB)
2185 SP--;
7716c5c5 2186 else if (IoTYPE(io) == IoTYPE_WRONLY) {
a5390457 2187 report_wrongway_fh(PL_last_in_gv, '>');
a00b5bd3 2188 }
a0d0e21e
LW
2189 }
2190 if (!fp) {
041457d9 2191 if ((!io || !(IoFLAGS(io) & IOf_START))
de7dabb6
TC
2192 && ckWARN(WARN_CLOSED)
2193 && type != OP_GLOB)
041457d9 2194 {
de7dabb6 2195 report_evil_fh(PL_last_in_gv);
3f4520fe 2196 }
54310121 2197 if (gimme == G_SCALAR) {
79628082 2198 /* undef TARG, and push that undefined value */
ba92458f 2199 if (type != OP_RCATLINE) {
aab1202a 2200 sv_setsv(TARG,NULL);
ba92458f 2201 }
a0d0e21e
LW
2202 PUSHTARG;
2203 }
2204 RETURN;
2205 }
a2008d6d 2206 have_fp:
54310121 2207 if (gimme == G_SCALAR) {
a0d0e21e 2208 sv = TARG;
0f722b55
RGS
2209 if (type == OP_RCATLINE && SvGMAGICAL(sv))
2210 mg_get(sv);
48de12d9
RGS
2211 if (SvROK(sv)) {
2212 if (type == OP_RCATLINE)
5668452f 2213 SvPV_force_nomg_nolen(sv);
48de12d9
RGS
2214 else
2215 sv_unref(sv);
2216 }
f7877b28 2217 else if (isGV_with_GP(sv)) {
5668452f 2218 SvPV_force_nomg_nolen(sv);
f7877b28 2219 }
862a34c6 2220 SvUPGRADE(sv, SVt_PV);
a0d0e21e 2221 tmplen = SvLEN(sv); /* remember if already alloced */
e3918bb7 2222 if (!tmplen && !SvREADONLY(sv) && !SvIsCOW(sv)) {
f72e8700
JJ
2223 /* try short-buffering it. Please update t/op/readline.t
2224 * if you change the growth length.
2225 */
2226 Sv_Grow(sv, 80);
2227 }
2b5e58c4
AMS
2228 offset = 0;
2229 if (type == OP_RCATLINE && SvOK(sv)) {
2230 if (!SvPOK(sv)) {
5668452f 2231 SvPV_force_nomg_nolen(sv);
2b5e58c4 2232 }
a0d0e21e 2233 offset = SvCUR(sv);
2b5e58c4 2234 }
a0d0e21e 2235 }
54310121 2236 else {
561b68a9 2237 sv = sv_2mortal(newSV(80));
54310121
PP
2238 offset = 0;
2239 }
fbad3eb5 2240
3887d568
AP
2241 /* This should not be marked tainted if the fp is marked clean */
2242#define MAYBE_TAINT_LINE(io, sv) \
2243 if (!(IoFLAGS(io) & IOf_UNTAINT)) { \
2244 TAINT; \
2245 SvTAINTED_on(sv); \
2246 }
2247
684bef36 2248/* delay EOF state for a snarfed empty file */
fbad3eb5 2249#define SNARF_EOF(gimme,rs,io,sv) \
684bef36 2250 (gimme != G_SCALAR || SvCUR(sv) \
b9fee9ba 2251 || (IoFLAGS(io) & IOf_NOLINE) || !RsSNARF(rs))
fbad3eb5 2252
a0d0e21e 2253 for (;;) {
09e8efcc 2254 PUTBACK;
fbad3eb5 2255 if (!sv_gets(sv, fp, offset)
2d726892
TF
2256 && (type == OP_GLOB
2257 || SNARF_EOF(gimme, PL_rs, io, sv)
2258 || PerlIO_error(fp)))
fbad3eb5 2259 {
760ac839 2260 PerlIO_clearerr(fp);
a0d0e21e 2261 if (IoFLAGS(io) & IOf_ARGV) {
157fb5a1 2262 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
a0d0e21e
LW
2263 if (fp)
2264 continue;
3280af22 2265 (void)do_close(PL_last_in_gv, FALSE);
a0d0e21e
LW
2266 }
2267 else if (type == OP_GLOB) {
a2a5de95
NC
2268 if (!do_close(PL_last_in_gv, FALSE)) {
2269 Perl_ck_warner(aTHX_ packWARN(WARN_GLOB),
2270 "glob failed (child exited with status %d%s)",
2271 (int)(STATUS_CURRENT >> 8),
2272 (STATUS_CURRENT & 0x80) ? ", core dumped" : "");
4eb79ab5 2273 }
a0d0e21e 2274 }
54310121 2275 if (gimme == G_SCALAR) {
ba92458f
AE
2276 if (type != OP_RCATLINE) {
2277 SV_CHECK_THINKFIRST_COW_DROP(TARG);
0c34ef67 2278 SvOK_off(TARG);
ba92458f 2279 }
09e8efcc 2280 SPAGAIN;
a0d0e21e
LW
2281 PUSHTARG;
2282 }
3887d568 2283 MAYBE_TAINT_LINE(io, sv);
a0d0e21e
LW
2284 RETURN;
2285 }
3887d568 2286 MAYBE_TAINT_LINE(io, sv);
a0d0e21e 2287 IoLINES(io)++;
b9fee9ba 2288 IoFLAGS(io) |= IOf_NOLINE;
71be2cbc 2289 SvSETMAGIC(sv);
09e8efcc 2290 SPAGAIN;
a0d0e21e 2291 XPUSHs(sv);
a0d0e21e 2292 if (type == OP_GLOB) {
349d4f2f 2293 const char *t1;
45a23732 2294 Stat_t statbuf;
a0d0e21e 2295
3280af22 2296 if (SvCUR(sv) > 0 && SvCUR(PL_rs) > 0) {
6136c704 2297 char * const tmps = SvEND(sv) - 1;
aa07b2f6 2298 if (*tmps == *SvPVX_const(PL_rs)) {
c07a80fd 2299 *tmps = '\0';
b162af07 2300 SvCUR_set(sv, SvCUR(sv) - 1);
c07a80fd
PP
2301 }
2302 }
349d4f2f 2303 for (t1 = SvPVX_const(sv); *t1; t1++)
b51c3e77
CB
2304#ifdef __VMS
2305 if (strchr("*%?", *t1))
2306#else
7ad1e72d 2307 if (strchr("$&*(){}[]'\";\\|?<>~`", *t1))
b51c3e77 2308#endif
a0d0e21e 2309 break;
45a23732 2310 if (*t1 && PerlLIO_lstat(SvPVX_const(sv), &statbuf) < 0) {
a0d0e21e
LW
2311 (void)POPs; /* Unmatched wildcard? Chuck it... */
2312 continue;
2313 }
2d79bf7f 2314 } else if (SvUTF8(sv)) { /* OP_READLINE, OP_RCATLINE */
d4c19fe8
AL
2315 if (ckWARN(WARN_UTF8)) {
2316 const U8 * const s = (const U8*)SvPVX_const(sv) + offset;
2317 const STRLEN len = SvCUR(sv) - offset;
2318 const U8 *f;
2319
2320 if (!is_utf8_string_loc(s, len, &f))
2321 /* Emulate :encoding(utf8) warning in the same case. */
2322 Perl_warner(aTHX_ packWARN(WARN_UTF8),
2323 "utf8 \"\\x%02X\" does not map to Unicode",
2324 f < (U8*)SvEND(sv) ? *f : 0);
2325 }
a0d0e21e 2326 }
54310121 2327 if (gimme == G_ARRAY) {
a0d0e21e 2328 if (SvLEN(sv) - SvCUR(sv) > 20) {
1da4ca5f 2329 SvPV_shrink_to_cur(sv);
a0d0e21e 2330 }
561b68a9 2331 sv = sv_2mortal(newSV(80));
a0d0e21e
LW
2332 continue;
2333 }
54310121 2334 else if (gimme == G_SCALAR && !tmplen && SvLEN(sv) - SvCUR(sv) > 80) {
a0d0e21e 2335 /* try to reclaim a bit of scalar space (only on 1st alloc) */
d5b5861b
NC
2336 const STRLEN new_len
2337 = SvCUR(sv) < 60 ? 80 : SvCUR(sv)+40; /* allow some slop */
1da4ca5f 2338 SvPV_renew(sv, new_len);
a0d0e21e
LW
2339 }
2340 RETURN;
2341 }
2342}
2343
a0d0e21e
LW
2344PP(pp_helem)
2345{
20b7effb 2346 dSP;
760ac839 2347 HE* he;
ae77835f 2348 SV **svp;
c445ea15 2349 SV * const keysv = POPs;
85fbaab2 2350 HV * const hv = MUTABLE_HV(POPs);
a3b680e6
AL
2351 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2352 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
be6c24e0 2353 SV *sv;
92970b93 2354 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
d30e492c 2355 bool preeminent = TRUE;
a0d0e21e 2356
6dfc73ea
SM
2357 if (SvTYPE(hv) != SVt_PVHV)
2358 RETPUSHUNDEF;
d4c19fe8 2359
92970b93 2360 if (localizing) {
d4c19fe8
AL
2361 MAGIC *mg;
2362 HV *stash;
d30e492c
VP
2363
2364 /* If we can determine whether the element exist,
2365 * Try to preserve the existenceness of a tied hash
2366 * element by using EXISTS and DELETE if possible.
2367 * Fallback to FETCH and STORE otherwise. */
2c5f48c2 2368 if (SvCANEXISTDELETE(hv))
d30e492c 2369 preeminent = hv_exists_ent(hv, keysv, 0);
d4c19fe8 2370 }
d30e492c 2371
5f9d7e2b 2372 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
d4c19fe8 2373 svp = he ? &HeVAL(he) : NULL;
a0d0e21e 2374 if (lval) {
746f6409 2375 if (!svp || !*svp || *svp == &PL_sv_undef) {
68dc0745
PP
2376 SV* lv;
2377 SV* key2;
2d8e6c8d 2378 if (!defer) {
be2597df 2379 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2d8e6c8d 2380 }
68dc0745
PP
2381 lv = sv_newmortal();
2382 sv_upgrade(lv, SVt_PVLV);
2383 LvTYPE(lv) = 'y';
6136c704 2384 sv_magic(lv, key2 = newSVsv(keysv), PERL_MAGIC_defelem, NULL, 0);
fc2b2dca 2385 SvREFCNT_dec_NN(key2); /* sv_magic() increments refcount */
0ad694a7 2386 LvTARG(lv) = SvREFCNT_inc_simple_NN(hv);
68dc0745
PP
2387 LvTARGLEN(lv) = 1;
2388 PUSHs(lv);
2389 RETURN;
2390 }
92970b93 2391 if (localizing) {
bfcb3514 2392 if (HvNAME_get(hv) && isGV(*svp))
159b6efe 2393 save_gp(MUTABLE_GV(*svp), !(PL_op->op_flags & OPf_SPECIAL));
47cfc530
VP
2394 else if (preeminent)
2395 save_helem_flags(hv, keysv, svp,
2396 (PL_op->op_flags & OPf_SPECIAL) ? 0 : SAVEf_SETMAGIC);
2397 else
2398 SAVEHDELETE(hv, keysv);
5f05dabc 2399 }
9026059d
GG
2400 else if (PL_op->op_private & OPpDEREF) {
2401 PUSHs(vivify_ref(*svp, PL_op->op_private & OPpDEREF));
2402 RETURN;
2403 }
a0d0e21e 2404 }
746f6409 2405 sv = (svp && *svp ? *svp : &PL_sv_undef);
fd69380d
DM
2406 /* Originally this did a conditional C<sv = sv_mortalcopy(sv)>; this
2407 * was to make C<local $tied{foo} = $tied{foo}> possible.
2408 * However, it seems no longer to be needed for that purpose, and
2409 * introduced a new bug: stuff like C<while ($hash{taintedval} =~ /.../g>
2410 * would loop endlessly since the pos magic is getting set on the
2411 * mortal copy and lost. However, the copy has the effect of
2412 * triggering the get magic, and losing it altogether made things like
2413 * c<$tied{foo};> in void context no longer do get magic, which some
2414 * code relied on. Also, delayed triggering of magic on @+ and friends
2415 * meant the original regex may be out of scope by now. So as a
2416 * compromise, do the get magic here. (The MGf_GSKIP flag will stop it
2417 * being called too many times). */
39cf747a 2418 if (!lval && SvRMAGICAL(hv) && SvGMAGICAL(sv))
fd69380d 2419 mg_get(sv);
be6c24e0 2420 PUSHs(sv);
a0d0e21e
LW
2421 RETURN;
2422}
2423
fedf30e1
DM
2424
2425/* a stripped-down version of Perl_softref2xv() for use by
2426 * pp_multideref(), which doesn't use PL_op->op_flags */
2427
f9db5646 2428STATIC GV *
fedf30e1
DM
2429S_softref2xv_lite(pTHX_ SV *const sv, const char *const what,
2430 const svtype type)
2431{
2432 if (PL_op->op_private & HINT_STRICT_REFS) {
2433 if (SvOK(sv))
2434 Perl_die(aTHX_ PL_no_symref_sv, sv,
2435 (SvPOKp(sv) && SvCUR(sv)>32 ? "..." : ""), what);
2436 else
2437 Perl_die(aTHX_ PL_no_usym, what);
2438 }
2439 if (!SvOK(sv))
2440 Perl_die(aTHX_ PL_no_usym, what);
2441 return gv_fetchsv_nomg(sv, GV_ADD, type);
2442}
2443
2444
79815f56
DM
2445/* Handle one or more aggregate derefs and array/hash indexings, e.g.
2446 * $h->{foo} or $a[0]{$key}[$i] or f()->[1]
fedf30e1
DM
2447 *
2448 * op_aux points to an array of unions of UV / IV / SV* / PADOFFSET.
79815f56
DM
2449 * Each of these either contains a set of actions, or an argument, such as
2450 * an IV to use as an array index, or a lexical var to retrieve.
2451 * Several actions re stored per UV; we keep shifting new actions off the
2452 * one UV, and only reload when it becomes zero.
fedf30e1
DM
2453 */
2454
2455PP(pp_multideref)
2456{
2457 SV *sv = NULL; /* init to avoid spurious 'may be used uninitialized' */
2458 UNOP_AUX_item *items = cUNOP_AUXx(PL_op)->op_aux;
2459 UV actions = items->uv;
2460
2461 assert(actions);
2462 /* this tells find_uninit_var() where we're up to */
2463 PL_multideref_pc = items;
2464
2465 while (1) {
2466 /* there are three main classes of action; the first retrieve
2467 * the initial AV or HV from a variable or the stack; the second
2468 * does the equivalent of an unrolled (/DREFAV, rv2av, aelem),
2469 * the third an unrolled (/DREFHV, rv2hv, helem).
2470 */
2471 switch (actions & MDEREF_ACTION_MASK) {
2472
2473 case MDEREF_reload:
2474 actions = (++items)->uv;
2475 continue;
2476
2477 case MDEREF_AV_padav_aelem: /* $lex[...] */
2478 sv = PAD_SVl((++items)->pad_offset);
2479 goto do_AV_aelem;
2480
2481 case MDEREF_AV_gvav_aelem: /* $pkg[...] */
2482 sv = UNOP_AUX_item_sv(++items);
2483 assert(isGV_with_GP(sv));
2484 sv = (SV*)GvAVn((GV*)sv);
2485 goto do_AV_aelem;
2486
2487 case MDEREF_AV_pop_rv2av_aelem: /* expr->[...] */
2488 {
2489 dSP;
2490 sv = POPs;
2491 PUTBACK;
2492 goto do_AV_rv2av_aelem;
2493 }
2494
2495 case MDEREF_AV_gvsv_vivify_rv2av_aelem: /* $pkg->[...] */
2496 sv = UNOP_AUX_item_sv(++items);
2497 assert(isGV_with_GP(sv));
2498 sv = GvSVn((GV*)sv);
2499 goto do_AV_vivify_rv2av_aelem;
2500
2501 case MDEREF_AV_padsv_vivify_rv2av_aelem: /* $lex->[...] */
2502 sv = PAD_SVl((++items)->pad_offset);
2503 /* FALLTHROUGH */
2504
2505 do_AV_vivify_rv2av_aelem:
2506 case MDEREF_AV_vivify_rv2av_aelem: /* vivify, ->[...] */
2507 /* this is the OPpDEREF action normally found at the end of
2508 * ops like aelem, helem, rv2sv */
2509 sv = vivify_ref(sv, OPpDEREF_AV);
2510 /* FALLTHROUGH */
2511
2512 do_AV_rv2av_aelem:
2513 /* this is basically a copy of pp_rv2av when it just has the
2514 * sKR/1 flags */
2515 SvGETMAGIC(sv);
2516 if (LIKELY(SvROK(sv))) {
2517 if (UNLIKELY(SvAMAGIC(sv))) {
2518 sv = amagic_deref_call(sv, to_av_amg);
2519 }
2520 sv = SvRV(sv);
2521 if (UNLIKELY(SvTYPE(sv) != SVt_PVAV))
2522 DIE(aTHX_ "Not an ARRAY reference");
2523 }
2524 else if (SvTYPE(sv) != SVt_PVAV) {
2525 if (!isGV_with_GP(sv))
2526 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "an ARRAY", SVt_PVAV);
2527 sv = MUTABLE_SV(GvAVn((GV*)sv));
2528 }
2529 /* FALLTHROUGH */
2530
2531 do_AV_aelem:
2532 {
2533 /* retrieve the key; this may be either a lexical or package
2534 * var (whose index/ptr is stored as an item) or a signed
2535 * integer constant stored as an item.
2536 */
2537 SV *elemsv;
2538 IV elem = 0; /* to shut up stupid compiler warnings */
2539
2540
2541 assert(SvTYPE(sv) == SVt_PVAV);
2542
2543 switch (actions & MDEREF_INDEX_MASK) {
2544 case MDEREF_INDEX_none:
2545 goto finish;
2546 case MDEREF_INDEX_const:
2547 elem = (++items)->iv;
2548 break;
2549 case MDEREF_INDEX_padsv:
2550 elemsv = PAD_SVl((++items)->pad_offset);
2551 goto check_elem;
2552 case MDEREF_INDEX_gvsv:
2553 elemsv = UNOP_AUX_item_sv(++items);
2554 assert(isGV_with_GP(elemsv));
2555 elemsv = GvSVn((GV*)elemsv);
2556 check_elem:
2557 if (UNLIKELY(SvROK(elemsv) && !SvGAMAGIC(elemsv)
2558 && ckWARN(WARN_MISC)))
2559 Perl_warner(aTHX_ packWARN(WARN_MISC),
147e3846 2560 "Use of reference \"%" SVf "\" as array index",
fedf30e1
DM
2561 SVfARG(elemsv));
2562 /* the only time that S_find_uninit_var() needs this
2563 * is to determine which index value triggered the
2564 * undef warning. So just update it here. Note that
2565 * since we don't save and restore this var (e.g. for
2566 * tie or overload execution), its value will be
2567 * meaningless apart from just here */
2568 PL_multideref_pc = items;
2569 elem = SvIV(elemsv);
2570 break;
2571 }
2572
2573
2574 /* this is basically a copy of pp_aelem with OPpDEREF skipped */
2575
2576 if (!(actions & MDEREF_FLAG_last)) {
2577 SV** svp = av_fetch((AV*)sv, elem, 1);
2578 if (!svp || ! (sv=*svp))
2579 DIE(aTHX_ PL_no_aelem, elem);
2580 break;
2581 }
2582
2583 if (PL_op->op_private &
2584 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
2585 {
2586 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
2587 sv = av_exists((AV*)sv, elem) ? &PL_sv_yes : &PL_sv_no;
2588 }
2589 else {
2590 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
2591 sv = av_delete((AV*)sv, elem, discard);
2592 if (discard)
2593 return NORMAL;
2594 if (!sv)
2595 sv = &PL_sv_undef;
2596 }
2597 }
2598 else {
2599 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2600 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
2601 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
2602 bool preeminent = TRUE;
2603 AV *const av = (AV*)sv;
2604 SV** svp;
2605
2606 if (UNLIKELY(localizing)) {
2607 MAGIC *mg;
2608 HV *stash;
2609
2610 /* If we can determine whether the element exist,
2611 * Try to preserve the existenceness of a tied array
2612 * element by using EXISTS and DELETE if possible.
2613 * Fallback to FETCH and STORE otherwise. */
2614 if (SvCANEXISTDELETE(av))
2615 preeminent = av_exists(av, elem);
2616 }
2617
2618 svp = av_fetch(av, elem, lval && !defer);
2619
2620 if (lval) {
2621 if (!svp || !(sv = *svp)) {
2622 IV len;
2623 if (!defer)
2624 DIE(aTHX_ PL_no_aelem, elem);
2625 len = av_tindex(av);
2626 sv = sv_2mortal(newSVavdefelem(av,
2627 /* Resolve a negative index now, unless it points
2628 * before the beginning of the array, in which
2629 * case record it for error reporting in
2630 * magic_setdefelem. */
2631 elem < 0 && len + elem >= 0
2632 ? len + elem : elem, 1));
2633 }
2634 else {
2635 if (UNLIKELY(localizing)) {
2636 if (preeminent) {
2637 save_aelem(av, elem, svp);
2638 sv = *svp; /* may have changed */
2639 }
2640 else
2641 SAVEADELETE(av, elem);
2642 }
2643 }
2644 }
2645 else {
2646 sv = (svp ? *svp : &PL_sv_undef);
2647 /* see note in pp_helem() */
2648 if (SvRMAGICAL(av) && SvGMAGICAL(sv))
2649 mg_get(sv);
2650 }
2651 }
2652
2653 }
2654 finish:
2655 {
2656 dSP;
2657 XPUSHs(sv);
2658 RETURN;
2659 }
2660 /* NOTREACHED */
2661
2662
2663
2664
2665 case MDEREF_HV_padhv_helem: /* $lex{...} */
2666 sv = PAD_SVl((++items)->pad_offset);
2667 goto do_HV_helem;
2668
2669 case MDEREF_HV_gvhv_helem: /* $pkg{...} */
2670 sv = UNOP_AUX_item_sv(++items);
2671 assert(isGV_with_GP(sv));
2672 sv = (SV*)GvHVn((GV*)sv);
2673 goto do_HV_helem;
2674
2675 case MDEREF_HV_pop_rv2hv_helem: /* expr->{...} */
2676 {
2677 dSP;
2678 sv = POPs;
2679 PUTBACK;
2680 goto do_HV_rv2hv_helem;
2681 }
2682
2683 case MDEREF_HV_gvsv_vivify_rv2hv_helem: /* $pkg->{...} */
2684 sv = UNOP_AUX_item_sv(++items);
2685 assert(isGV_with_GP(sv));
2686 sv = GvSVn((GV*)sv);
2687 goto do_HV_vivify_rv2hv_helem;
2688
2689 case MDEREF_HV_padsv_vivify_rv2hv_helem: /* $lex->{...} */
2690 sv = PAD_SVl((++items)->pad_offset);
2691 /* FALLTHROUGH */
2692
2693 do_HV_vivify_rv2hv_helem:
2694 case MDEREF_HV_vivify_rv2hv_helem: /* vivify, ->{...} */
2695 /* this is the OPpDEREF action normally found at the end of
2696 * ops like aelem, helem, rv2sv */
2697 sv = vivify_ref(sv, OPpDEREF_HV);
2698 /* FALLTHROUGH */
2699
2700 do_HV_rv2hv_helem:
2701 /* this is basically a copy of pp_rv2hv when it just has the
2702 * sKR/1 flags (and pp_rv2hv is aliased to pp_rv2av) */
2703
2704 SvGETMAGIC(sv);
2705 if (LIKELY(SvROK(sv))) {
2706 if (UNLIKELY(SvAMAGIC(sv))) {
2707 sv = amagic_deref_call(sv, to_hv_amg);
2708 }
2709 sv = SvRV(sv);
2710 if (UNLIKELY(SvTYPE(sv) != SVt_PVHV))
2711 DIE(aTHX_ "Not a HASH reference");
2712 }
2713 else if (SvTYPE(sv) != SVt_PVHV) {
2714 if (!isGV_with_GP(sv))
2715 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "a HASH", SVt_PVHV);
2716 sv = MUTABLE_SV(GvHVn((GV*)sv));
2717 }
2718 /* FALLTHROUGH */
2719
2720 do_HV_helem:
2721 {
2722 /* retrieve the key; this may be either a lexical / package
2723 * var or a string constant, whose index/ptr is stored as an
2724 * item
2725 */
2726 SV *keysv = NULL; /* to shut up stupid compiler warnings */
2727
2728 assert(SvTYPE(sv) == SVt_PVHV);
2729
2730 switch (actions & MDEREF_INDEX_MASK) {
2731 case MDEREF_INDEX_none:
2732 goto finish;
2733
2734 case MDEREF_INDEX_const:
2735 keysv = UNOP_AUX_item_sv(++items);
2736 break;
2737
2738 case MDEREF_INDEX_padsv:
2739 keysv = PAD_SVl((++items)->pad_offset);
2740 break;
2741
2742 case MDEREF_INDEX_gvsv:
2743 keysv = UNOP_AUX_item_sv(++items);
2744 keysv = GvSVn((GV*)keysv);
2745 break;
2746 }
2747
2748 /* see comment above about setting this var */
2749 PL_multideref_pc = items;
2750
2751
2752 /* ensure that candidate CONSTs have been HEKified */
2753 assert( ((actions & MDEREF_INDEX_MASK) != MDEREF_INDEX_const)
2754 || SvTYPE(keysv) >= SVt_PVMG
2755 || !SvOK(keysv)
2756 || SvROK(keysv)
2757 || SvIsCOW_shared_hash(keysv));
2758
2759 /* this is basically a copy of pp_helem with OPpDEREF skipped */
2760
2761 if (!(actions & MDEREF_FLAG_last)) {
2762 HE *he = hv_fetch_ent((HV*)sv, keysv, 1, 0);
2763 if (!he || !(sv=HeVAL(he)) || sv == &PL_sv_undef)
2764 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2765 break;
2766 }
2767
2768 if (PL_op->op_private &
2769 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
2770 {
2771 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
2772 sv = hv_exists_ent((HV*)sv, keysv, 0)
2773 ? &PL_sv_yes : &PL_sv_no;
2774 }
2775 else {
2776 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
2777 sv = hv_delete_ent((HV*)sv, keysv, discard, 0);
2778 if (discard)
2779 return NORMAL;
2780 if (!sv)
2781 sv = &PL_sv_undef;
2782 }
2783 }
2784 else {
2785 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2786 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
2787 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
2788 bool preeminent = TRUE;
2789 SV **svp;
2790 HV * const hv = (HV*)sv;
2791 HE* he;
2792
2793 if (UNLIKELY(localizing)) {
2794 MAGIC *mg;
2795 HV *stash;
2796
2797 /* If we can determine whether the element exist,
2798 * Try to preserve the existenceness of a tied hash
2799 * element by using EXISTS and DELETE if possible.
2800 * Fallback to FETCH and STORE otherwise. */
2801 if (SvCANEXISTDELETE(hv))
2802 preeminent = hv_exists_ent(hv, keysv, 0);
2803 }
2804
2805 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
2806 svp = he ? &HeVAL(he) : NULL;
2807
2808
2809 if (lval) {
2810 if (!svp || !(sv = *svp) || sv == &PL_sv_undef) {
2811 SV* lv;
2812 SV* key2;
2813 if (!defer)
2814 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2815 lv = sv_newmortal();
2816 sv_upgrade(lv, SVt_PVLV);
2817 LvTYPE(lv) = 'y';
2818 sv_magic(lv, key2 = newSVsv(keysv),
2819 PERL_MAGIC_defelem, NULL, 0);
2820 /* sv_magic() increments refcount */
2821 SvREFCNT_dec_NN(key2);
0ad694a7 2822 LvTARG(lv) = SvREFCNT_inc_simple_NN(hv);
fedf30e1
DM
2823 LvTARGLEN(lv) = 1;
2824 sv = lv;
2825 }
2826 else {
2827 if (localizing) {
2828 if (HvNAME_get(hv) && isGV(sv))
2829 save_gp(MUTABLE_GV(sv),
2830 !(PL_op->op_flags & OPf_SPECIAL));
2831 else if (preeminent) {
2832 save_helem_flags(hv, keysv, svp,
2833 (PL_op->op_flags & OPf_SPECIAL)
2834 ? 0 : SAVEf_SETMAGIC);
2835 sv = *svp; /* may have changed */
2836 }
2837 else
2838 SAVEHDELETE(hv, keysv);
2839 }
2840 }
2841 }
2842 else {
2843 sv = (svp && *svp ? *svp : &PL_sv_undef);
2844 /* see note in pp_helem() */
2845 if (SvRMAGICAL(hv) && SvGMAGICAL(sv))
2846 mg_get(sv);
2847 }
2848 }
2849 goto finish;
2850 }
2851
2852 } /* switch */
2853
2854 actions >>= MDEREF_SHIFT;
2855 } /* while */
2856 /* NOTREACHED */
2857}
2858
2859
a0d0e21e
LW
2860PP(pp_iter)
2861{
eb578fdb 2862 PERL_CONTEXT *cx;
7d6c2cef 2863 SV *oldsv;
1d7c1841 2864 SV **itersvp;
8a1f10dd 2865 SV *retsv;
a0d0e21e 2866
84f05d57
JH
2867 SV *sv;
2868 AV *av;
2869 IV ix;
2870 IV inc;
2871
4ebe6e95 2872 cx = CX_CUR();
1d7c1841 2873 itersvp = CxITERVAR(cx);
4b5c941e 2874 assert(itersvp);
a48ce6be
DM
2875
2876 switch (CxTYPE(cx)) {
17c91640 2877
b552b52c
DM
2878 case CXt_LOOP_LAZYSV: /* string increment */
2879 {
2880 SV* cur = cx->blk_loop.state_u.lazysv.cur;
2881 SV *end = cx->blk_loop.state_u.lazysv.end;
2882 /* If the maximum is !SvOK(), pp_enteriter substitutes PL_sv_no.
2883 It has SvPVX of "" and SvCUR of 0, which is what we want. */
2884 STRLEN maxlen = 0;
2885 const char *max = SvPV_const(end, maxlen);
d6c970c7
AC
2886 if (DO_UTF8(end) && IN_UNI_8_BIT)
2887 maxlen = sv_len_utf8_nomg(end);
5d9574c1 2888 if (UNLIKELY(SvNIOK(cur) || SvCUR(cur) > maxlen))
8a1f10dd 2889 goto retno;
b552b52c
DM
2890
2891 oldsv = *itersvp;
6d3ca00e
DM
2892 /* NB: on the first iteration, oldsv will have a ref count of at
2893 * least 2 (one extra from blk_loop.itersave), so the GV or pad
2894 * slot will get localised; on subsequent iterations the RC==1
2895 * optimisation may kick in and the SV will be reused. */
2896 if (oldsv && LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
b552b52c
DM
2897 /* safe to reuse old SV */
2898 sv_setsv(oldsv, cur);
a48ce6be 2899 }
b552b52c
DM
2900 else
2901 {
2902 /* we need a fresh SV every time so that loop body sees a
2903 * completely new SV for closures/references to work as
2904 * they used to */
2905 *itersvp = newSVsv(cur);
6d3ca00e 2906 SvREFCNT_dec(oldsv);
b552b52c
DM
2907 }
2908 if (strEQ(SvPVX_const(cur), max))
2909 sv_setiv(cur, 0); /* terminate next time */
2910 else
2911 sv_inc(cur);
2912 break;
2913 }
a48ce6be 2914
fcef60b4
DM
2915 case CXt_LOOP_LAZYIV: /* integer increment */
2916 {
2917 IV cur = cx->blk_loop.state_u.lazyiv.cur;
5d9574c1 2918 if (UNLIKELY(cur > cx->blk_loop.state_u.lazyiv.end))
8a1f10dd 2919 goto retno;
7f61b687 2920
fcef60b4 2921 oldsv = *itersvp;
6d3ca00e
DM
2922 /* see NB comment above */
2923 if (oldsv && LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
eaa5c2d6 2924 /* safe to reuse old SV */
47b96a1e
DM
2925
2926 if ( (SvFLAGS(oldsv) & (SVTYPEMASK|SVf_THINKFIRST|SVf_IVisUV))
2927 == SVt_IV)
2928 {
2929 /* Cheap SvIOK_only().
2930 * Assert that flags which SvIOK_only() would test or
2931 * clear can't be set, because we're SVt_IV */
2932 assert(!(SvFLAGS(oldsv) &
2933 (SVf_OOK|SVf_UTF8|(SVf_OK & ~(SVf_IOK|SVp_IOK)))));
2934 SvFLAGS(oldsv) |= (SVf_IOK|SVp_IOK);
2935 /* SvIV_set() where sv_any points to head */
2936 oldsv->sv_u.svu_iv = cur;
2937
2938 }
2939 else
2940 sv_setiv(oldsv, cur);
eaa5c2d6 2941 }
1c846c1f 2942 else
eaa5c2d6
GA
2943 {
2944 /* we need a fresh SV every time so that loop body sees a
2945 * completely new SV for closures/references to work as they
2946 * used to */
fcef60b4 2947 *itersvp = newSViv(cur);
6d3ca00e 2948 SvREFCNT_dec(oldsv);
eaa5c2d6 2949 }
a2309040 2950
5d9574c1 2951 if (UNLIKELY(cur == IV_MAX)) {
cdc1aa42
NC
2952 /* Handle end of range at IV_MAX */
2953 cx->blk_loop.state_u.lazyiv.end = IV_MIN;
2954 } else
2955 ++cx->blk_loop.state_u.lazyiv.cur;
a48ce6be 2956 break;
fcef60b4 2957 }
a48ce6be 2958
93661e56
DM
2959 case CXt_LOOP_LIST: /* for (1,2,3) */
2960
2961 assert(OPpITER_REVERSED == 2); /* so inc becomes -1 or 1 */
2962 inc = 1 - (PL_op->op_private & OPpITER_REVERSED);
2963 ix = (cx->blk_loop.state_u.stack.ix += inc);
2964 if (UNLIKELY(inc > 0
2965 ? ix > cx->blk_oldsp
2966 : ix <= cx->blk_loop.state_u.stack.basesp)
2967 )
8a1f10dd 2968 goto retno;
93661e56
DM
2969
2970 sv = PL_stack_base[ix];
2971 av = NULL;
2972 goto loop_ary_common;
2973
2974 case CXt_LOOP_ARY: /* for (@ary) */
2975
2976 av = cx->blk_loop.state_u.ary.ary;
2977 inc = 1 - (PL_op->op_private & OPpITER_REVERSED);
2978 ix = (cx->blk_loop.state_u.ary.ix += inc);
2979 if (UNLIKELY(inc > 0
2980 ? ix > AvFILL(av)
2981 : ix < 0)
2982 )
8a1f10dd 2983 goto retno;
de080daa 2984
9d1ee8e0 2985 if (UNLIKELY(SvRMAGICAL(av))) {
a8a20bb6
DM
2986 SV * const * const svp = av_fetch(av, ix, FALSE);
2987 sv = svp ? *svp : NULL;
2988 }
2989 else {
2990 sv = AvARRAY(av)[ix];
de080daa 2991 }
ef3e5ea9 2992
93661e56
DM
2993 loop_ary_common:
2994
d39c26a6
FC
2995 if (UNLIKELY(cx->cx_type & CXp_FOR_LVREF)) {
2996 SvSetMagicSV(*itersvp, sv);
2997 break;
2998 }
2999
5d9574c1
DM
3000 if (LIKELY(sv)) {
3001 if (UNLIKELY(SvIS_FREED(sv))) {
f38aa882
DM
3002 *itersvp = NULL;
3003 Perl_croak(aTHX_ "Use of freed value in iteration");
3004 }
60779a30 3005 if (SvPADTMP(sv)) {
8e079c2a 3006 sv = newSVsv(sv);
60779a30 3007 }
8e079c2a
FC
3008 else {
3009 SvTEMP_off(sv);
3010 SvREFCNT_inc_simple_void_NN(sv);
3011 }
de080daa 3012 }
93661e56 3013 else if (av) {
199f858d 3014 sv = newSVavdefelem(av, ix, 0);
de080daa 3015 }
a600f7e6
FC
3016 else
3017 sv = &PL_sv_undef;
a0d0e21e 3018
de080daa
DM
3019 oldsv = *itersvp;
3020 *itersvp = sv;
3021 SvREFCNT_dec(oldsv);
de080daa 3022 break;
a48ce6be
DM
3023
3024 default:
3025 DIE(aTHX_ "panic: pp_iter, type=%u", CxTYPE(cx));
3026 }
8a1f10dd
DM
3027
3028 retsv = &PL_sv_yes;
3029 if (0) {
3030 retno:
3031 retsv = &PL_sv_no;
3032 }
3033 /* pp_enteriter should have pre-extended the stack */
3034 assert(PL_stack_sp < PL_stack_max);
3035 *++PL_stack_sp =retsv;
3036
3037 return PL_op->op_next;
a0d0e21e
LW
3038}
3039
ef07e810
DM
3040/*
3041A description of how taint works in pattern matching and substitution.
3042
284167a5
SM
3043This is all conditional on NO_TAINT_SUPPORT not being defined. Under
3044NO_TAINT_SUPPORT, taint-related operations should become no-ops.
3045
4e19c54b 3046While the pattern is being assembled/concatenated and then compiled,
284167a5
SM
3047PL_tainted will get set (via TAINT_set) if any component of the pattern
3048is tainted, e.g. /.*$tainted/. At the end of pattern compilation,
3049the RXf_TAINTED flag is set on the pattern if PL_tainted is set (via
1738e041
DM
3050TAINT_get). It will also be set if any component of the pattern matches
3051based on locale-dependent behavior.
ef07e810 3052
0ab462a6
DM
3053When the pattern is copied, e.g. $r = qr/..../, the SV holding the ref to
3054the pattern is marked as tainted. This means that subsequent usage, such
284167a5
SM
3055as /x$r/, will set PL_tainted using TAINT_set, and thus RXf_TAINTED,
3056on the new pattern too.
ef07e810 3057
272d35c9 3058RXf_TAINTED_SEEN is used post-execution by the get magic code
ef07e810
DM
3059of $1 et al to indicate whether the returned value should be tainted.
3060It is the responsibility of the caller of the pattern (i.e. pp_match,
3061pp_subst etc) to set this flag for any other circumstances where $1 needs
3062to be tainted.
3063
3064The taint behaviour of pp_subst (and pp_substcont) is quite complex.
3065
3066There are three possible sources of taint
3067 * the source string
3068 * the pattern (both compile- and run-time, RXf_TAINTED / RXf_TAINTED_SEEN)
3069 * the replacement string (or expression under /e)
3070
3071There are four destinations of taint and they are affected by the sources
3072according to the rules below:
3073
3074 * the return value (not including /r):
3075 tainted by the source string and pattern, but only for the
3076 number-of-iterations case; boolean returns aren't tainted;
3077 * the modified string (or modified copy under /r):
3078 tainted by the source string, pattern, and replacement strings;
3079 * $1 et al:
3080 tainted by the pattern, and under 'use re "taint"', by the source
3081 string too;
3082 * PL_taint - i.e. whether subsequent code (e.g. in a /e block) is tainted:
3083 should always be unset before executing subsequent code.
3084
3085The overall action of pp_subst is:
3086
3087 * at the start, set bits in rxtainted indicating the taint status of
3088 the various sources.
3089
3090 * After each pattern execution, update the SUBST_TAINT_PAT bit in
3091 rxtainted if RXf_TAINTED_SEEN has been set, to indicate that the
3092 pattern has subsequently become tainted via locale ops.
3093
3094 * If control is being passed to pp_substcont to execute a /e block,
3095 save rxtainted in the CXt_SUBST block, for future use by
3096 pp_substcont.
3097
3098 * Whenever control is being returned to perl code (either by falling
3099 off the "end" of pp_subst/pp_substcont, or by entering a /e block),
3100 use the flag bits in rxtainted to make all the appropriate types of
0ab462a6
DM
3101 destination taint visible; e.g. set RXf_TAINTED_SEEN so that $1
3102 et al will appear tainted.
ef07e810
DM
3103
3104pp_match is just a simpler version of the above.
3105
3106*/
3107
a0d0e21e
LW
3108PP(pp_subst)
3109{
20b7effb 3110 dSP; dTARG;
eb578fdb 3111 PMOP *pm = cPMOP;
a0d0e21e 3112 PMOP *rpm = pm;
eb578fdb 3113 char *s;
a0d0e21e 3114 char *strend;
5c144d81 3115 const char *c;
a0d0e21e 3116 STRLEN clen;
3c6ef0a5
FC
3117 SSize_t iters = 0;
3118 SSize_t maxiters;
a0d0e21e 3119 bool once;
ef07e810
DM
3120 U8 rxtainted = 0; /* holds various SUBST_TAINT_* flag bits.
3121 See "how taint works" above */
a0d0e21e 3122 char *orig;
1ed74d04 3123 U8 r_flags;
eb578fdb 3124 REGEXP *rx = PM_GETRE(pm);
a0d0e21e
LW
3125 STRLEN len;
3126 int force_on_match = 0;
0bcc34c2 3127 const I32 oldsave = PL_savestack_ix;
792b2c16 3128 STRLEN slen;
26a74523 3129 bool doutf8 = FALSE; /* whether replacement is in utf8 */
db2c6cb3 3130#ifdef PERL_ANY_COW
106d9a13 3131 bool was_cow;
ed252734 3132#endif
a0714e2c 3133 SV *nsv = NULL;
b770e143 3134 /* known replacement string? */
eb578fdb 3135 SV *dstr = (pm->op_pmflags & PMf_CONST) ? POPs : NULL;
a0d0e21e 3136
f410a211
NC
3137 PERL_ASYNC_CHECK();
3138
533c011a 3139 if (PL_op->op_flags & OPf_STACKED)
a0d0e21e 3140 TARG = POPs;
6ffceeb7 3141 else if (ARGTARG)
59f00321 3142 GETTARGET;
a0d0e21e 3143 else {
54b9620d 3144 TARG = DEFSV;
a0d0e21e 3145 EXTEND(SP,1);
1c846c1f 3146 }
d9f424b2 3147
64534138 3148 SvGETMAGIC(TARG); /* must come before cow check */
db2c6cb3 3149#ifdef PERL_ANY_COW
106d9a13
DM
3150 /* note that a string might get converted to COW during matching */
3151 was_cow = cBOOL(SvIsCOW(TARG));
ed252734 3152#endif
d13a5d3b
TC
3153 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
3154#ifndef PERL_ANY_COW
3155 if (SvIsCOW(TARG))
3156 sv_force_normal_flags(TARG,0);
3157#endif
3158 if ((SvREADONLY(TARG)
3159 || ( ((SvTYPE(TARG) == SVt_PVGV && isGV_with_GP(TARG))
3160 || SvTYPE(TARG) > SVt_PVLV)
3161 && !(SvTYPE(TARG) == SVt_PVGV && SvFAKE(TARG)))))
3162 Perl_croak_no_modify();
3163 }
8ec5e241
NIS
3164 PUTBACK;
3165
6ac6605d
DM
3166 orig = SvPV_nomg(TARG, len);
3167 /* note we don't (yet) force the var into being a string; if we fail
92711104 3168 * to match, we leave as-is; on successful match however, we *will*
6ac6605d 3169 * coerce into a string, then repeat the match */
4499db73 3170 if (!SvPOKp(TARG) || SvTYPE(TARG) == SVt_PVGV || SvVOK(TARG))
a0d0e21e 3171 force_on_match = 1;
20be6587
DM
3172
3173 /* only replace once? */
3174 once = !(rpm->op_pmflags & PMf_GLOBAL);
3175
ef07e810 3176 /* See "how taint works" above */
284167a5 3177 if (TAINTING_get) {
20be6587
DM
3178 rxtainted = (
3179 (SvTAINTED(TARG) ? SUBST_TAINT_STR : 0)
284167a5 3180 | (RX_ISTAINTED(rx) ? SUBST_TAINT_PAT : 0)
20be6587
DM
3181 | ((pm->op_pmflags & PMf_RETAINT) ? SUBST_TAINT_RETAINT : 0)
3182 | ((once && !(rpm->op_pmflags & PMf_NONDESTRUCT))
3183 ? SUBST_TAINT_BOOLRET : 0));
3184 TAINT_NOT;
3185 }
a12c0f56 3186
a0d0e21e 3187 force_it:
6ac6605d
DM
3188 if (!pm || !orig)
3189 DIE(aTHX_ "panic: pp_subst, pm=%p, orig=%p", pm, orig);
a0d0e21e 3190
6ac6605d
DM
3191 strend = orig + len;
3192 slen = DO_UTF8(TARG) ? utf8_length((U8*)orig, (U8*)strend) : len;
792b2c16
JH
3193 maxiters = 2 * slen + 10; /* We can match twice at each
3194 position, once with zero-length,
3195 second time with non-zero. */
a0d0e21e 3196
794826f4
YO
3197 /* handle the empty pattern */
3198 if (!RX_PRELEN(rx) && PL_curpm && !ReANY(rx)->mother_re) {
5585e758
YO
3199 if (PL_curpm == PL_reg_curpm) {
3200 if (PL_curpm_under) {
3201 if (PL_curpm_under == PL_reg_curpm) {
3202 Perl_croak(aTHX_ "Infinite recursion via empty pattern");
3203 } else {
3204 pm = PL_curpm_under;
3205 }
3206 }
3207 } else {
3208 pm = PL_curpm;
3209 }
3210 rx = PM_GETRE(pm);
a0d0e21e 3211 }
6502e081 3212
6e240d0b 3213#ifdef PERL_SAWAMPERSAND
6502e081
DM
3214 r_flags = ( RX_NPARENS(rx)
3215 || PL_sawampersand
6502e081 3216 || (RX_EXTFLAGS(rx) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
5b0e71e9 3217 || (rpm->op_pmflags & PMf_KEEPCOPY)
6502e081
DM
3218 )
3219 ? REXEC_COPY_STR
3220 : 0;
6e240d0b
FC
3221#else
3222 r_flags = REXEC_COPY_STR;
3223#endif
7fba1cd6 3224
0395280b 3225 if (!CALLREGEXEC(rx, orig, strend, orig, 0, TARG, NULL, r_flags))
8b64c330 3226 {
5e79dfb9
DM
3227 SPAGAIN;
3228 PUSHs(rpm->op_pmflags & PMf_NONDESTRUCT ? TARG : &PL_sv_no);
3229 LEAVE_SCOPE(oldsave);
3230 RETURN;
3231 }
1754320d
FC
3232 PL_curpm = pm;
3233
71be2cbc 3234 /* known replacement string? */
f272994b 3235 if (dstr) {
8514a05a
JH
3236 /* replacement needing upgrading? */
3237 if (DO_UTF8(TARG) && !doutf8) {
db79b45b 3238 nsv = sv_newmortal();
4a176938 3239 SvSetSV(nsv, dstr);
8df0e7a2 3240 sv_utf8_upgrade(nsv);
5c144d81 3241 c = SvPV_const(nsv, clen);
4a176938
JH
3242 doutf8 = TRUE;
3243 }
3244 else {
5c144d81 3245 c = SvPV_const(dstr, clen);
4a176938 3246 doutf8 = DO_UTF8(dstr);
8514a05a 3247 }
bb933b9b
FC
3248
3249 if (SvTAINTED(dstr))
3250 rxtainted |= SUBST_TAINT_REPL;
f272994b
A
3251 }
3252 else {
6136c704 3253 c = NULL;
f272994b
A
3254 doutf8 = FALSE;
3255 }
3256
71be2cbc 3257 /* can do inplace substitution? */
ed252734 3258 if (c
db2c6cb3 3259#ifdef PERL_ANY_COW
106d9a13 3260 && !was_cow
ed252734 3261#endif
fbfb1899 3262 && (I32)clen <= RX_MINLENRET(rx)
9cefd268
FC
3263 && ( once
3264 || !(r_flags & REXEC_COPY_STR)
3265 || (!SvGMAGICAL(dstr) && !(RX_EXTFLAGS(rx) & RXf_EVAL_SEEN))
3266 )
dbc200c5 3267 && !(RX_EXTFLAGS(rx) & RXf_NO_INPLACE_SUBST)
8ca8a454
NC
3268 && (!doutf8 || SvUTF8(TARG))
3269 && !(rpm->op_pmflags & PMf_NONDESTRUCT))
8b030b38 3270 {
ec911639 3271
db2c6cb3 3272#ifdef PERL_ANY_COW
106d9a13 3273 /* string might have got converted to COW since we set was_cow */
ed252734 3274 if (SvIsCOW(TARG)) {
f7a8268c 3275 if (!force_on_match)
ed252734 3276 goto have_a_cow;
f7a8268c 3277 assert(SvVOK(TARG));
ed252734
NC
3278 }
3279#endif
71be2cbc 3280 if (force_on_match) {
6ac6605d
DM
3281 /* redo the first match, this time with the orig var
3282 * forced into being a string */
71be2cbc 3283 force_on_match = 0;
6ac6605d 3284 orig = SvPV_force_nomg(TARG, len);
71be2cbc
PP
3285 goto force_it;
3286 }
39b40493 3287
71be2cbc 3288 if (once) {
c67ab8f2 3289 char *d, *m;
20be6587
DM
3290 if (RX_MATCH_TAINTED(rx)) /* run time pattern taint, eg locale */
3291 rxtainted |= SUBST_TAINT_PAT;
07bc277f
NC
3292 m = orig + RX_OFFS(rx)[0].start;
3293 d = orig + RX_OFFS(rx)[0].end;
71be2cbc
PP
3294 s = orig;
3295 if (m - s > strend - d) { /* faster to shorten from end */
2ec7214c 3296 I32 i;
71be2cbc
PP
3297 if (clen) {
3298 Copy(c, m, clen, char);
3299 m += clen;
a0d0e21e 3300 }
71be2cbc
PP
3301 i = strend - d;
3302 if (i > 0) {
3303 Move(d, m, i, char);
3304 m += i;
a0d0e21e 3305 }
71be2cbc
PP
3306 *m = '\0';
3307 SvCUR_set(TARG, m - s);
3308 }
2ec7214c
DM
3309 else { /* faster from front */
3310 I32 i = m - s;
71be2cbc 3311 d -= clen;
2ec7214c
DM
3312 if (i > 0)
3313 Move(s, d - i, i, char);
71be2cbc 3314 sv_chop(TARG, d-i);
71be2cbc 3315 if (clen)
c947cd8d 3316 Copy(c, d, clen, char);
71be2cbc 3317 }
8ec5e241 3318 SPAGAIN;
8ca8a454 3319 PUSHs(&PL_sv_yes);
71be2cbc
PP
3320 }
3321 else {
c67ab8f2 3322 char *d, *m;
0395280b 3323 d = s = RX_OFFS(rx)[0].start + orig;
71be2cbc 3324 do {
2b25edcf 3325 I32 i;
5d9574c1 3326 if (UNLIKELY(iters++ > maxiters))
cea2e8a9 3327 DIE(aTHX_ "Substitution loop");
5d9574c1 3328 if (UNLIKELY(RX_MATCH_TAINTED(rx))) /* run time pattern taint, eg locale */
20be6587 3329 rxtainted |= SUBST_TAINT_PAT;
07bc277f 3330 m = RX_OFFS(rx)[0].start + orig;
155aba94 3331 if ((i = m - s)) {
71be2cbc
PP
3332 if (s != d)
3333 Move(s, d, i, char);
3334 d += i;
a0d0e21e 3335 }
71be2cbc
PP
3336 if (clen) {
3337 Copy(c, d, clen, char);
3338 d += clen;
3339 }
07bc277f 3340 s = RX_OFFS(rx)[0].end + orig;
7ce41e5c
FC
3341 } while (CALLREGEXEC(rx, s, strend, orig,
3342 s == m, /* don't match same null twice */
f722798b 3343 TARG, NULL,
d5e7783a 3344 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
71be2cbc 3345 if (s != d) {
2b25edcf 3346 I32 i = strend - s;
aa07b2f6 3347 SvCUR_set(TARG, d - SvPVX_const(TARG) + i);
71be2cbc 3348 Move(s, d, i+1, char); /* include the NUL */
a0d0e21e 3349 }
8ec5e241 3350 SPAGAIN;
3c6ef0a5 3351 mPUSHi(iters);
a0d0e21e
LW
3352 }
3353 }
ff6e92e8 3354 else {
1754320d 3355 bool first;
c67ab8f2 3356 char *m;
1754320d 3357 SV *repl;
a0d0e21e 3358 if (force_on_match) {
6ac6605d
DM
3359 /* redo the first match, this time with the orig var
3360 * forced into being a string */
a0d0e21e 3361 force_on_match = 0;
0c1438a1
NC
3362 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
3363 /* I feel that it should be possible to avoid this mortal copy
3364 given that the code below copies into a new destination.
3365 However, I suspect it isn't worth the complexity of
3366 unravelling the C<goto force_it> for the small number of
3367 cases where it would be viable to drop into the copy code. */
3368 TARG = sv_2mortal(newSVsv(TARG));
3369 }
6ac6605d 3370 orig = SvPV_force_nomg(TARG, len);
a0d0e21e
LW
3371 goto force_it;
3372 }
db2c6cb3 3373#ifdef PERL_ANY_COW
ed252734
NC
3374 have_a_cow:
3375#endif
20be6587
DM
3376 if (RX_MATCH_TAINTED(rx)) /* run time pattern taint, eg locale */
3377 rxtainted |= SUBST_TAINT_PAT;
1754320d 3378 repl = dstr;
0395280b
DM
3379 s = RX_OFFS(rx)[0].start + orig;
3380 dstr = newSVpvn_flags(orig, s-orig,
3381 SVs_TEMP | (DO_UTF8(TARG) ? SVf_UTF8 : 0));
a0d0e21e 3382 if (!c) {
eb578fdb 3383 PERL_CONTEXT *cx;
8ec5e241 3384 SPAGAIN;
0395280b 3385 m = orig;
20be6587
DM
3386 /* note that a whole bunch of local vars are saved here for
3387 * use by pp_substcont: here's a list of them in case you're
3388 * searching for places in this sub that uses a particular var:
3389 * iters maxiters r_flags oldsave rxtainted orig dstr targ
3390 * s m strend rx once */
490576d1 3391 CX_PUSHSUBST(cx);
20e98b0f 3392 RETURNOP(cPMOP->op_pmreplrootu.op_pmreplroot);
a0d0e21e 3393 }
1754320d 3394 first = TRUE;
a0d0e21e 3395 do {
5d9574c1 3396 if (UNLIKELY(iters++ > maxiters))
cea2e8a9 3397 DIE(aTHX_ "Substitution loop");
5d9574c1 3398 if (UNLIKELY(RX_MATCH_TAINTED(rx)))
20be6587 3399 rxtainted |= SUBST_TAINT_PAT;
07bc277f 3400 if (RX_MATCH_COPIED(rx) && RX_SUBBEG(rx) != orig) {
c67ab8f2
DM
3401 char *old_s = s;
3402 char *old_orig = orig;
6502e081 3403 assert(RX_SUBOFFSET(rx) == 0);
c67ab8f2 3404
07bc277f 3405 orig = RX_SUBBEG(rx);
c67ab8f2
DM
3406 s = orig + (old_s - old_orig);
3407 strend = s + (strend - old_s);
a0d0e21e 3408 }
07bc277f 3409 m = RX_OFFS(rx)[0].start + orig;
64534138 3410 sv_catpvn_nomg_maybeutf8(dstr, s, m - s, DO_UTF8(TARG));
07bc277f 3411 s = RX_OFFS(rx)[0].end + orig;
1754320d
FC
3412 if (first) {
3413 /* replacement already stringified */
3414 if (clen)
64534138 3415 sv_catpvn_nomg_maybeutf8(dstr, c, clen, doutf8);
1754320d
FC
3416 first = FALSE;
3417 }
3418 else {
8df0e7a2 3419 sv_catsv(dstr, repl);
5d9574c1 3420 if (UNLIKELY(SvTAINTED(repl)))
bb933b9b 3421 rxtainted |= SUBST_TAINT_REPL;
1754320d 3422 }
a0d0e21e
LW
3423 if (once)
3424 break;
ff27773b
KW
3425 } while (CALLREGEXEC(rx, s, strend, orig,
3426 s == m, /* Yields minend of 0 or 1 */
d5e7783a
DM
3427 TARG, NULL,
3428 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
aba224f7 3429 assert(strend >= s);
64534138 3430 sv_catpvn_nomg_maybeutf8(dstr, s, strend - s, DO_UTF8(TARG));
748a9306 3431
8ca8a454
NC
3432 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
3433 /* From here on down we're using the copy, and leaving the original
3434 untouched. */
3435 TARG = dstr;
3436 SPAGAIN;
3437 PUSHs(dstr);
3438 } else {
db2c6cb3 3439#ifdef PERL_ANY_COW
8ca8a454
NC
3440 /* The match may make the string COW. If so, brilliant, because
3441 that's just saved us one malloc, copy and free - the regexp has
3442 donated the old buffer, and we malloc an entirely new one, rather
3443 than the regexp malloc()ing a buffer and copying our original,
3444 only for us to throw it away here during the substitution. */
3445 if (SvIsCOW(TARG)) {
3446 sv_force_normal_flags(TARG, SV_COW_DROP_PV);
3447 } else
ed252734 3448#endif
8ca8a454
NC
3449 {
3450 SvPV_free(TARG);
3451 }
3452 SvPV_set(TARG, SvPVX(dstr));
3453 SvCUR_set(TARG, SvCUR(dstr));
3454 SvLEN_set(TARG, SvLEN(dstr));
64534138 3455 SvFLAGS(TARG) |= SvUTF8(dstr);
8ca8a454 3456 SvPV_set(dstr, NULL);
748a9306 3457
8ca8a454 3458 SPAGAIN;
3c6ef0a5 3459 mPUSHi(iters);
8ca8a454
NC
3460 }
3461 }
3462
3463 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
3464 (void)SvPOK_only_UTF8(TARG);
a0d0e21e 3465 }
20be6587 3466
ef07e810 3467 /* See "how taint works" above */
284167a5 3468 if (TAINTING_get) {
20be6587
DM
3469 if ((rxtainted & SUBST_TAINT_PAT) ||
3470 ((rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_RETAINT)) ==
3471 (SUBST_TAINT_STR|SUBST_TAINT_RETAINT))
3472 )
3473 (RX_MATCH_TAINTED_on(rx)); /* taint $1 et al */
3474
3475 if (!(rxtainted & SUBST_TAINT_BOOLRET)
3476 && (rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT))
3477 )
3478 SvTAINTED_on(TOPs); /* taint return value */
3479 else
3480 SvTAINTED_off(TOPs); /* may have got tainted earlier */
3481
3482 /* needed for mg_set below */
284167a5
SM
3483 TAINT_set(
3484 cBOOL(rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT|SUBST_TAINT_REPL))
3485 );
20be6587
DM
3486 SvTAINT(TARG);
3487 }
3488 SvSETMAGIC(TARG); /* PL_tainted must be correctly set for this mg_set */
3489 TAINT_NOT;
f1a76097
DM
3490 LEAVE_SCOPE(oldsave);
3491 RETURN;
a0d0e21e
LW
3492}
3493
3494PP(pp_grepwhile)
3495{
20b7effb 3496 dSP;
a0d0e21e
LW
3497
3498 if (SvTRUEx(POPs))
3280af22
NIS
3499 PL_stack_base[PL_markstack_ptr[-1]++] = PL_stack_base[*PL_markstack_ptr];
3500 ++*PL_markstack_ptr;
b2a2a901 3501 FREETMPS;
d343c3ef 3502 LEAVE_with_name("grep_item"); /* exit inner scope */
a0d0e21e
LW
3503
3504 /* All done yet? */
5d9574c1 3505 if (UNLIKELY(PL_stack_base + *PL_markstack_ptr > SP)) {
a0d0e21e 3506 I32 items;
1c23e2bd 3507 const U8 gimme = GIMME_V;
a0d0e21e 3508
d343c3ef 3509 LEAVE_with_name("grep"); /* exit outer scope */
a0d0e21e 3510 (void)POPMARK; /* pop src */
3280af22 3511 items = --*PL_markstack_ptr - PL_markstack_ptr[-1];
a0d0e21e 3512 (void)POPMARK; /* pop dst */
3280af22 3513 SP = PL_stack_base + POPMARK; /* pop original mark */
54310121 3514 if (gimme == G_SCALAR) {
7cc47870
RGS
3515 dTARGET;
3516 XPUSHi(items);
a0d0e21e 3517 }
54310121
PP
3518 else if (gimme == G_ARRAY)
3519 SP += items;
a0d0e21e
LW
3520 RETURN;
3521 }
3522 else {
3523 SV *src;
3524
d343c3ef 3525 ENTER_with_name("grep_item"); /* enter inner scope */
1d7c1841 3526 SAVEVPTR(PL_curpm);
a0d0e21e 3527
6cae08a8 3528 src = PL_stack_base[TOPMARK];
60779a30 3529 if (SvPADTMP(src)) {
6cae08a8 3530 src = PL_stack_base[TOPMARK] = sv_mortalcopy(src);
a0ed822e
FC
3531 PL_tmps_floor++;
3532 }
a0d0e21e 3533 SvTEMP_off(src);
ffd49c98 3534 DEFSV_set(src);
a0d0e21e
LW
3535
3536 RETURNOP(cLOGOP->op_other);
3537 }
3538}
3539
799da9d7 3540/* leave_adjust_stacks():
f7a874b8 3541 *
e02ce34b
DM
3542 * Process a scope's return args (in the range from_sp+1 .. PL_stack_sp),
3543 * positioning them at to_sp+1 onwards, and do the equivalent of a
3544 * FREEMPS and TAINT_NOT.
3545 *
f7a874b8
DM
3546 * Not intended to be called in void context.
3547 *
799da9d7
DM
3548 * When leaving a sub, eval, do{} or other scope, the things that need
3549 * doing to process the return args are:
f7a874b8 3550 * * in scalar context, only return the last arg (or PL_sv_undef if none);
799da9d7
DM
3551 * * for the types of return that return copies of their args (such
3552 * as rvalue sub return), make a mortal copy of every return arg,
3553 * except where we can optimise the copy away without it being
3554 * semantically visible;
3555 * * make sure that the arg isn't prematurely freed; in the case of an
3556 * arg not copied, this may involve mortalising it. For example, in
f7a874b8
DM
3557 * C<sub f { my $x = ...; $x }>, $x would be freed when we do
3558 * CX_LEAVE_SCOPE(cx) unless it's protected or copied.
3559 *
799da9d7
DM
3560 * What condition to use when deciding whether to pass the arg through
3561 * or make a copy, is determined by the 'pass' arg; its valid values are:
3562 * 0: rvalue sub/eval exit
3563 * 1: other rvalue scope exit
3564 * 2: :lvalue sub exit in rvalue context
3565 * 3: :lvalue sub exit in lvalue context and other lvalue scope exits
3566 *
f7a874b8 3567 * There is a big issue with doing a FREETMPS. We would like to free any
799da9d7 3568 * temps created by the last statement which the sub executed, rather than
f7a874b8
DM
3569 * leaving them for the caller. In a situation where a sub call isn't
3570 * soon followed by a nextstate (e.g. nested recursive calls, a la
3571 * fibonacci()), temps can accumulate, causing memory and performance
3572 * issues.
3573 *
3574 * On the other hand, we don't want to free any TEMPs which are keeping
799da9d7
DM
3575 * alive any return args that we skipped copying; nor do we wish to undo
3576 * any mortalising done here.
f7a874b8
DM
3577 *
3578 * The solution is to split the temps stack frame into two, with a cut
3579 * point delineating the two halves. We arrange that by the end of this
3580 * function, all the temps stack frame entries we wish to keep are in the
799da9d7 3581 * range PL_tmps_floor+1.. tmps_base-1, while the ones to free now are in
f7a874b8
DM
3582 * the range tmps_base .. PL_tmps_ix. During the course of this
3583 * function, tmps_base starts off as PL_tmps_floor+1, then increases
3584 * whenever we find or create a temp that we know should be kept. In
3585 * general the stuff above tmps_base is undecided until we reach the end,
3586 * and we may need a sort stage for that.
3587 *
3588 * To determine whether a TEMP is keeping a return arg alive, every
3589 * arg that is kept rather than copied and which has the SvTEMP flag
3590 * set, has the flag temporarily unset, to mark it. At the end we scan
799da9d7 3591 * the temps stack frame above the cut for entries without SvTEMP and
f7a874b8 3592 * keep them, while turning SvTEMP on again. Note that if we die before
799da9d7 3593 * the SvTEMPs flags are set again, its safe: at worst, subsequent use of
f7a874b8
DM
3594 * those SVs may be slightly less efficient.
3595 *
3596 * In practice various optimisations for some common cases mean we can
3597 * avoid most of the scanning and swapping about with the temps stack.
3598 */
3599
799da9d7 3600void
1c23e2bd 3601Perl_leave_adjust_stacks(pTHX_ SV **from_sp, SV **to_sp, U8 gimme, int pass)
a0d0e21e 3602{
263e0548 3603 dVAR;
20b7effb 3604 dSP;
f7a874b8
DM
3605 SSize_t tmps_base; /* lowest index into tmps stack that needs freeing now */
3606 SSize_t nargs;
3607
799da9d7
DM
3608 PERL_ARGS_ASSERT_LEAVE_ADJUST_STACKS;
3609
f7a874b8
DM
3610 TAINT_NOT;
3611
3612 if (gimme == G_ARRAY) {
e02ce34b
DM
3613 nargs = SP - from_sp;
3614 from_sp++;
f7a874b8
DM
3615 }
3616 else {
3617 assert(gimme == G_SCALAR);
e02ce34b 3618 if (UNLIKELY(from_sp >= SP)) {
f7a874b8 3619 /* no return args */
e02ce34b 3620 assert(from_sp == SP);
f7a874b8
DM
3621 EXTEND(SP, 1);
3622 *++SP = &PL_sv_undef;
e02ce34b 3623 to_sp = SP;
f7a874b8
DM
3624 nargs = 0;
3625 }
3626 else {
3627 from_sp = SP;
3628 nargs = 1;
3629 }
3630 }
3631
3632 /* common code for G_SCALAR and G_ARRAY */
3633
3634 tmps_base = PL_tmps_floor + 1;
3635