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[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)))
1042 SETs(HvUSEDKEYS(sv) ? &PL_sv_yes : sv_2mortal(newSViv(0)));
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
DM
1710 if (!SvIMMORTAL(lsv)) {
1711 if (UNLIKELY(
1712 SvTEMP(lsv) && !SvSMAGICAL(lsv) && SvREFCNT(lsv) == 1 &&
1713 (!isGV_with_GP(lsv) || SvFAKE(lsv)) && ckWARN(WARN_MISC)
1714 ))
1715 Perl_warner(aTHX_
1716 packWARN(WARN_MISC),
1717 "Useless assignment to a temporary"
1718 );
1719 sv_setsv(lsv, *relem);
1720 *relem = lsv;
1721 SvSETMAGIC(lsv);
1722 }
1723 if (++relem > lastrelem)
1724 goto no_relems;
a0d0e21e 1725 break;
8b0c3377
DM
1726 } /* switch */
1727 } /* while */
1728
1729
1730 no_relems:
1731
1732 /* simplified lelem loop for when there are no relems left */
1733 while (LIKELY(lelem <= lastlelem)) {
1734 SV *lsv = *lelem++;
c73f612f
DM
1735
1736 TAINT_NOT; /* Each item stands on its own, taintwise. */
1737
8b0c3377
DM
1738 if (UNLIKELY(!lsv)) {
1739 lsv = *lelem++;
1740 ASSUME(SvTYPE(lsv) == SVt_PVAV);
a0d0e21e 1741 }
8b0c3377
DM
1742
1743 switch (SvTYPE(lsv)) {
1744 case SVt_PVAV:
b09ed995
DM
1745 if (SvRMAGICAL(lsv) || AvFILLp((SV*)lsv) >= 0) {
1746 av_clear((AV*)lsv);
8b0c3377 1747 if (UNLIKELY(PL_delaymagic & DM_ARRAY_ISA))
b09ed995 1748 SvSETMAGIC(lsv);
8b0c3377
DM
1749 }
1750 break;
1751
1752 case SVt_PVHV:
b09ed995
DM
1753 if (SvRMAGICAL(lsv) || HvUSEDKEYS((HV*)lsv))
1754 hv_clear((HV*)lsv);
8b0c3377
DM
1755 break;
1756
1757 default:
1758 if (!SvIMMORTAL(lsv)) {
1759 sv_setsv(lsv, &PL_sv_undef);
1760 SvSETMAGIC(lsv);
b09ed995 1761 *relem++ = lsv;
8b0c3377
DM
1762 }
1763 break;
1764 } /* switch */
1765 } /* while */
1766
c73f612f
DM
1767 TAINT_NOT; /* result of list assign isn't tainted */
1768
5d9574c1 1769 if (UNLIKELY(PL_delaymagic & ~DM_DELAY)) {
985213f2 1770 /* Will be used to set PL_tainting below */
dfff4baf
BF
1771 Uid_t tmp_uid = PerlProc_getuid();
1772 Uid_t tmp_euid = PerlProc_geteuid();
1773 Gid_t tmp_gid = PerlProc_getgid();
1774 Gid_t tmp_egid = PerlProc_getegid();
985213f2 1775
b469f1e0 1776 /* XXX $> et al currently silently ignore failures */
3280af22 1777 if (PL_delaymagic & DM_UID) {
a0d0e21e 1778#ifdef HAS_SETRESUID
b469f1e0
JH
1779 PERL_UNUSED_RESULT(
1780 setresuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
1781 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1,
1782 (Uid_t)-1));
56febc5e
AD
1783#else
1784# ifdef HAS_SETREUID
b469f1e0
JH
1785 PERL_UNUSED_RESULT(
1786 setreuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
1787 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1));
56febc5e
AD
1788# else
1789# ifdef HAS_SETRUID
b28d0864 1790 if ((PL_delaymagic & DM_UID) == DM_RUID) {
b469f1e0 1791 PERL_UNUSED_RESULT(setruid(PL_delaymagic_uid));
b28d0864 1792 PL_delaymagic &= ~DM_RUID;
a0d0e21e 1793 }
56febc5e
AD
1794# endif /* HAS_SETRUID */
1795# ifdef HAS_SETEUID
b28d0864 1796 if ((PL_delaymagic & DM_UID) == DM_EUID) {
b469f1e0 1797 PERL_UNUSED_RESULT(seteuid(PL_delaymagic_euid));
b28d0864 1798 PL_delaymagic &= ~DM_EUID;
a0d0e21e 1799 }
56febc5e 1800# endif /* HAS_SETEUID */
b28d0864 1801 if (PL_delaymagic & DM_UID) {
985213f2 1802 if (PL_delaymagic_uid != PL_delaymagic_euid)
cea2e8a9 1803 DIE(aTHX_ "No setreuid available");
b469f1e0 1804 PERL_UNUSED_RESULT(PerlProc_setuid(PL_delaymagic_uid));
a0d0e21e 1805 }
56febc5e
AD
1806# endif /* HAS_SETREUID */
1807#endif /* HAS_SETRESUID */
04783dc7 1808
985213f2
AB
1809 tmp_uid = PerlProc_getuid();
1810 tmp_euid = PerlProc_geteuid();
a0d0e21e 1811 }
b469f1e0 1812 /* XXX $> et al currently silently ignore failures */
3280af22 1813 if (PL_delaymagic & DM_GID) {
a0d0e21e 1814#ifdef HAS_SETRESGID
b469f1e0
JH
1815 PERL_UNUSED_RESULT(
1816 setresgid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
1817 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1,
1818 (Gid_t)-1));
56febc5e
AD
1819#else
1820# ifdef HAS_SETREGID
b469f1e0
JH
1821 PERL_UNUSED_RESULT(
1822 setregid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
1823 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1));
56febc5e
AD
1824# else
1825# ifdef HAS_SETRGID
b28d0864 1826 if ((PL_delaymagic & DM_GID) == DM_RGID) {
b469f1e0 1827 PERL_UNUSED_RESULT(setrgid(PL_delaymagic_gid));
b28d0864 1828 PL_delaymagic &= ~DM_RGID;
a0d0e21e 1829 }
56febc5e
AD
1830# endif /* HAS_SETRGID */
1831# ifdef HAS_SETEGID
b28d0864 1832 if ((PL_delaymagic & DM_GID) == DM_EGID) {
b469f1e0 1833 PERL_UNUSED_RESULT(setegid(PL_delaymagic_egid));
b28d0864 1834 PL_delaymagic &= ~DM_EGID;
a0d0e21e 1835 }
56febc5e 1836# endif /* HAS_SETEGID */
b28d0864 1837 if (PL_delaymagic & DM_GID) {
985213f2 1838 if (PL_delaymagic_gid != PL_delaymagic_egid)
cea2e8a9 1839 DIE(aTHX_ "No setregid available");
b469f1e0 1840 PERL_UNUSED_RESULT(PerlProc_setgid(PL_delaymagic_gid));
a0d0e21e 1841 }
56febc5e
AD
1842# endif /* HAS_SETREGID */
1843#endif /* HAS_SETRESGID */
04783dc7 1844
985213f2
AB
1845 tmp_gid = PerlProc_getgid();
1846 tmp_egid = PerlProc_getegid();
a0d0e21e 1847 }
284167a5 1848 TAINTING_set( TAINTING_get | (tmp_uid && (tmp_euid != tmp_uid || tmp_egid != tmp_gid)) );
9a9b5ec9
DM
1849#ifdef NO_TAINT_SUPPORT
1850 PERL_UNUSED_VAR(tmp_uid);
1851 PERL_UNUSED_VAR(tmp_euid);
1852 PERL_UNUSED_VAR(tmp_gid);
1853 PERL_UNUSED_VAR(tmp_egid);
1854#endif
a0d0e21e 1855 }
a68090fe 1856 PL_delaymagic = old_delaymagic;
54310121 1857
54310121
PP
1858 if (gimme == G_VOID)
1859 SP = firstrelem - 1;
1860 else if (gimme == G_SCALAR) {
1861 dTARGET;
1862 SP = firstrelem;
b09ed995 1863 EXTEND(SP,1);
8b0c3377 1864 SETi(firstlelem - firstrelem);
54310121 1865 }
b09ed995
DM
1866 else
1867 SP = relem - 1;
08aeb9f7 1868
54310121 1869 RETURN;
a0d0e21e
LW
1870}
1871
8782bef2
GB
1872PP(pp_qr)
1873{
20b7effb 1874 dSP;
eb578fdb 1875 PMOP * const pm = cPMOP;
fe578d7f 1876 REGEXP * rx = PM_GETRE(pm);
10599a69 1877 SV * const pkg = rx ? CALLREG_PACKAGE(rx) : NULL;
c4420975 1878 SV * const rv = sv_newmortal();
d63c20f2
DM
1879 CV **cvp;
1880 CV *cv;
288b8c02
NC
1881
1882 SvUPGRADE(rv, SVt_IV);
c2123ae3
NC
1883 /* For a subroutine describing itself as "This is a hacky workaround" I'm
1884 loathe to use it here, but it seems to be the right fix. Or close.
1885 The key part appears to be that it's essential for pp_qr to return a new
1886 object (SV), which implies that there needs to be an effective way to
1887 generate a new SV from the existing SV that is pre-compiled in the
1888 optree. */
1889 SvRV_set(rv, MUTABLE_SV(reg_temp_copy(NULL, rx)));
288b8c02
NC
1890 SvROK_on(rv);
1891
8d919b0a 1892 cvp = &( ReANY((REGEXP *)SvRV(rv))->qr_anoncv);
5d9574c1 1893 if (UNLIKELY((cv = *cvp) && CvCLONE(*cvp))) {
d63c20f2 1894 *cvp = cv_clone(cv);
fc2b2dca 1895 SvREFCNT_dec_NN(cv);
d63c20f2
DM
1896 }
1897
288b8c02 1898 if (pkg) {
f815daf2 1899 HV *const stash = gv_stashsv(pkg, GV_ADD);
fc2b2dca 1900 SvREFCNT_dec_NN(pkg);
288b8c02
NC
1901 (void)sv_bless(rv, stash);
1902 }
1903
5d9574c1 1904 if (UNLIKELY(RX_ISTAINTED(rx))) {
e08e52cf 1905 SvTAINTED_on(rv);
9274aefd
DM
1906 SvTAINTED_on(SvRV(rv));
1907 }
c8c13c22 1908 XPUSHs(rv);
1909 RETURN;
8782bef2
GB
1910}
1911
a0d0e21e
LW
1912PP(pp_match)
1913{
20b7effb 1914 dSP; dTARG;
eb578fdb 1915 PMOP *pm = cPMOP;
d65afb4b 1916 PMOP *dynpm = pm;
eb578fdb 1917 const char *s;
5c144d81 1918 const char *strend;
99a90e59 1919 SSize_t curpos = 0; /* initial pos() or current $+[0] */
a0d0e21e 1920 I32 global;
7fadf4a7 1921 U8 r_flags = 0;
5c144d81 1922 const char *truebase; /* Start of string */
eb578fdb 1923 REGEXP *rx = PM_GETRE(pm);
b3eb6a9b 1924 bool rxtainted;
1c23e2bd 1925 const U8 gimme = GIMME_V;
a0d0e21e 1926 STRLEN len;
a3b680e6 1927 const I32 oldsave = PL_savestack_ix;
e60df1fa 1928 I32 had_zerolen = 0;
b1422d62 1929 MAGIC *mg = NULL;
a0d0e21e 1930
533c011a 1931 if (PL_op->op_flags & OPf_STACKED)
a0d0e21e 1932 TARG = POPs;
6ffceeb7 1933 else if (ARGTARG)
59f00321 1934 GETTARGET;
a0d0e21e 1935 else {
54b9620d 1936 TARG = DEFSV;
a0d0e21e
LW
1937 EXTEND(SP,1);
1938 }
d9f424b2 1939
c277df42 1940 PUTBACK; /* EVAL blocks need stack_sp. */
69dc4b30
FC
1941 /* Skip get-magic if this is a qr// clone, because regcomp has
1942 already done it. */
f1d31338 1943 truebase = ReANY(rx)->mother_re
69dc4b30
FC
1944 ? SvPV_nomg_const(TARG, len)
1945 : SvPV_const(TARG, len);
f1d31338 1946 if (!truebase)
2269b42e 1947 DIE(aTHX_ "panic: pp_match");
f1d31338 1948 strend = truebase + len;
284167a5
SM
1949 rxtainted = (RX_ISTAINTED(rx) ||
1950 (TAINT_get && (pm->op_pmflags & PMf_RETAINT)));
9212bbba 1951 TAINT_NOT;
a0d0e21e 1952
6c864ec2 1953 /* We need to know this in case we fail out early - pos() must be reset */
de0df3c0
MH
1954 global = dynpm->op_pmflags & PMf_GLOBAL;
1955
d65afb4b 1956 /* PMdf_USED is set after a ?? matches once */
c737faaf
YO
1957 if (
1958#ifdef USE_ITHREADS
1959 SvREADONLY(PL_regex_pad[pm->op_pmoffset])
1960#else
1961 pm->op_pmflags & PMf_USED
1962#endif
1963 ) {
e5dc5375 1964 DEBUG_r(PerlIO_printf(Perl_debug_log, "?? already matched once"));
de0df3c0 1965 goto nope;
a0d0e21e
LW
1966 }
1967
5585e758
YO
1968 /* handle the empty pattern */
1969 if (!RX_PRELEN(rx) && PL_curpm && !ReANY(rx)->mother_re) {
1970 if (PL_curpm == PL_reg_curpm) {
1971 if (PL_curpm_under) {
1972 if (PL_curpm_under == PL_reg_curpm) {
1973 Perl_croak(aTHX_ "Infinite recursion via empty pattern");
1974 } else {
1975 pm = PL_curpm_under;
1976 }
1977 }
1978 } else {
1979 pm = PL_curpm;
1980 }
1981 rx = PM_GETRE(pm);
a0d0e21e 1982 }
d65afb4b 1983
389ecb56 1984 if (RX_MINLEN(rx) >= 0 && (STRLEN)RX_MINLEN(rx) > len) {
75d43e96 1985 DEBUG_r(PerlIO_printf(Perl_debug_log, "String shorter than min possible regex match (%"
147e3846 1986 UVuf " < %" IVdf ")\n",
75d43e96 1987 (UV)len, (IV)RX_MINLEN(rx)));
de0df3c0 1988 goto nope;
e5dc5375 1989 }
c277df42 1990
8ef97b0e 1991 /* get pos() if //g */
de0df3c0 1992 if (global) {
b1422d62 1993 mg = mg_find_mglob(TARG);
8ef97b0e 1994 if (mg && mg->mg_len >= 0) {
25fdce4a 1995 curpos = MgBYTEPOS(mg, TARG, truebase, len);
8ef97b0e
DM
1996 /* last time pos() was set, it was zero-length match */
1997 if (mg->mg_flags & MGf_MINMATCH)
1998 had_zerolen = 1;
1999 }
a0d0e21e 2000 }
8ef97b0e 2001
6e240d0b 2002#ifdef PERL_SAWAMPERSAND
a41aa44d 2003 if ( RX_NPARENS(rx)
6502e081 2004 || PL_sawampersand
6502e081 2005 || (RX_EXTFLAGS(rx) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
5b0e71e9 2006 || (dynpm->op_pmflags & PMf_KEEPCOPY)
6e240d0b
FC
2007 )
2008#endif
2009 {
6502e081
DM
2010 r_flags |= (REXEC_COPY_STR|REXEC_COPY_SKIP_PRE);
2011 /* in @a =~ /(.)/g, we iterate multiple times, but copy the buffer
2012 * only on the first iteration. Therefore we need to copy $' as well
2013 * as $&, to make the rest of the string available for captures in
2014 * subsequent iterations */
2015 if (! (global && gimme == G_ARRAY))
2016 r_flags |= REXEC_COPY_SKIP_POST;
2017 };
5b0e71e9
DM
2018#ifdef PERL_SAWAMPERSAND
2019 if (dynpm->op_pmflags & PMf_KEEPCOPY)
2020 /* handle KEEPCOPY in pmop but not rx, eg $r=qr/a/; /$r/p */
2021 r_flags &= ~(REXEC_COPY_SKIP_PRE|REXEC_COPY_SKIP_POST);
2022#endif
22e551b9 2023
f1d31338
DM
2024 s = truebase;
2025
d7be1480 2026 play_it_again:
985afbc1 2027 if (global)
03c83e26 2028 s = truebase + curpos;
f722798b 2029
77da2310 2030 if (!CALLREGEXEC(rx, (char*)s, (char *)strend, (char*)truebase,
03c83e26 2031 had_zerolen, TARG, NULL, r_flags))
03b6c93d 2032 goto nope;
77da2310
NC
2033
2034 PL_curpm = pm;
985afbc1 2035 if (dynpm->op_pmflags & PMf_ONCE)
c737faaf 2036#ifdef USE_ITHREADS
77da2310 2037 SvREADONLY_on(PL_regex_pad[dynpm->op_pmoffset]);
c737faaf 2038#else
77da2310 2039 dynpm->op_pmflags |= PMf_USED;
c737faaf 2040#endif
a0d0e21e 2041
72311751
GS
2042 if (rxtainted)
2043 RX_MATCH_TAINTED_on(rx);
2044 TAINT_IF(RX_MATCH_TAINTED(rx));
35c2ccc3
DM
2045
2046 /* update pos */
2047
2048 if (global && (gimme != G_ARRAY || (dynpm->op_pmflags & PMf_CONTINUE))) {
b1422d62 2049 if (!mg)
35c2ccc3 2050 mg = sv_magicext_mglob(TARG);
25fdce4a 2051 MgBYTEPOS_set(mg, TARG, truebase, RX_OFFS(rx)[0].end);
adf51885
DM
2052 if (RX_ZERO_LEN(rx))
2053 mg->mg_flags |= MGf_MINMATCH;
2054 else
2055 mg->mg_flags &= ~MGf_MINMATCH;
35c2ccc3
DM
2056 }
2057
bf9dff51
DM
2058 if ((!RX_NPARENS(rx) && !global) || gimme != G_ARRAY) {
2059 LEAVE_SCOPE(oldsave);
2060 RETPUSHYES;
2061 }
2062
88ab22af
DM
2063 /* push captures on stack */
2064
bf9dff51 2065 {
07bc277f 2066 const I32 nparens = RX_NPARENS(rx);
a3b680e6 2067 I32 i = (global && !nparens) ? 1 : 0;
a0d0e21e 2068
c277df42 2069 SPAGAIN; /* EVAL blocks could move the stack. */
ffc61ed2
JH
2070 EXTEND(SP, nparens + i);
2071 EXTEND_MORTAL(nparens + i);
2072 for (i = !i; i <= nparens; i++) {
a0d0e21e 2073 PUSHs(sv_newmortal());
5d9574c1
DM
2074 if (LIKELY((RX_OFFS(rx)[i].start != -1)
2075 && RX_OFFS(rx)[i].end != -1 ))
2076 {
07bc277f 2077 const I32 len = RX_OFFS(rx)[i].end - RX_OFFS(rx)[i].start;
f1d31338 2078 const char * const s = RX_OFFS(rx)[i].start + truebase;
5d9574c1
DM
2079 if (UNLIKELY(RX_OFFS(rx)[i].end < 0 || RX_OFFS(rx)[i].start < 0
2080 || len < 0 || len > strend - s))
5637ef5b 2081 DIE(aTHX_ "panic: pp_match start/end pointers, i=%ld, "
147e3846 2082 "start=%ld, end=%ld, s=%p, strend=%p, len=%" UVuf,
5637ef5b
NC
2083 (long) i, (long) RX_OFFS(rx)[i].start,
2084 (long)RX_OFFS(rx)[i].end, s, strend, (UV) len);
a0d0e21e 2085 sv_setpvn(*SP, s, len);
cce850e4 2086 if (DO_UTF8(TARG) && is_utf8_string((U8*)s, len))
a197cbdd 2087 SvUTF8_on(*SP);
a0d0e21e
LW
2088 }
2089 }
2090 if (global) {
0e0b3e82 2091 curpos = (UV)RX_OFFS(rx)[0].end;
03c83e26 2092 had_zerolen = RX_ZERO_LEN(rx);
c277df42 2093 PUTBACK; /* EVAL blocks may use stack */
cf93c79d 2094 r_flags |= REXEC_IGNOREPOS | REXEC_NOT_FIRST;
a0d0e21e
LW
2095 goto play_it_again;
2096 }
4633a7c4 2097 LEAVE_SCOPE(oldsave);
a0d0e21e
LW
2098 RETURN;
2099 }
e5964223 2100 NOT_REACHED; /* NOTREACHED */
a0d0e21e 2101
7b52d656 2102 nope:
d65afb4b 2103 if (global && !(dynpm->op_pmflags & PMf_CONTINUE)) {
b1422d62
DM
2104 if (!mg)
2105 mg = mg_find_mglob(TARG);
2106 if (mg)
2107 mg->mg_len = -1;
a0d0e21e 2108 }
4633a7c4 2109 LEAVE_SCOPE(oldsave);
a0d0e21e
LW
2110 if (gimme == G_ARRAY)
2111 RETURN;
2112 RETPUSHNO;
2113}
2114
2115OP *
864dbfa3 2116Perl_do_readline(pTHX)
a0d0e21e 2117{
20b7effb 2118 dSP; dTARGETSTACKED;
eb578fdb 2119 SV *sv;
a0d0e21e
LW
2120 STRLEN tmplen = 0;
2121 STRLEN offset;
760ac839 2122 PerlIO *fp;
eb578fdb
KW
2123 IO * const io = GvIO(PL_last_in_gv);
2124 const I32 type = PL_op->op_type;
1c23e2bd 2125 const U8 gimme = GIMME_V;
a0d0e21e 2126
6136c704 2127 if (io) {
50db69d8 2128 const MAGIC *const mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar);
6136c704 2129 if (mg) {
3e0cb5de 2130 Perl_tied_method(aTHX_ SV_CONST(READLINE), SP, MUTABLE_SV(io), mg, gimme, 0);
6136c704 2131 if (gimme == G_SCALAR) {
50db69d8
NC
2132 SPAGAIN;
2133 SvSetSV_nosteal(TARG, TOPs);
2134 SETTARG;
6136c704 2135 }
50db69d8 2136 return NORMAL;
0b7c7b4f 2137 }
e79b0511 2138 }
4608196e 2139 fp = NULL;
a0d0e21e
LW
2140 if (io) {
2141 fp = IoIFP(io);
2142 if (!fp) {
2143 if (IoFLAGS(io) & IOf_ARGV) {
2144 if (IoFLAGS(io) & IOf_START) {
a0d0e21e 2145 IoLINES(io) = 0;
b9f2b683 2146 if (av_tindex(GvAVn(PL_last_in_gv)) < 0) {
1d7c1841 2147 IoFLAGS(io) &= ~IOf_START;
d5eb9a46 2148 do_open6(PL_last_in_gv, "-", 1, NULL, NULL, 0);
4bac9ae4 2149 SvTAINTED_off(GvSVn(PL_last_in_gv)); /* previous tainting irrelevant */
76f68e9b 2150 sv_setpvs(GvSVn(PL_last_in_gv), "-");
3280af22 2151 SvSETMAGIC(GvSV(PL_last_in_gv));
a2008d6d
GS
2152 fp = IoIFP(io);
2153 goto have_fp;
a0d0e21e
LW
2154 }
2155 }
157fb5a1 2156 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
a0d0e21e 2157 if (!fp) { /* Note: fp != IoIFP(io) */
3280af22 2158 (void)do_close(PL_last_in_gv, FALSE); /* now it does*/
a0d0e21e
LW
2159 }
2160 }
0d44d22b
NC
2161 else if (type == OP_GLOB)
2162 fp = Perl_start_glob(aTHX_ POPs, io);
a0d0e21e
LW
2163 }
2164 else if (type == OP_GLOB)
2165 SP--;
7716c5c5 2166 else if (IoTYPE(io) == IoTYPE_WRONLY) {
a5390457 2167 report_wrongway_fh(PL_last_in_gv, '>');
a00b5bd3 2168 }
a0d0e21e
LW
2169 }
2170 if (!fp) {
041457d9 2171 if ((!io || !(IoFLAGS(io) & IOf_START))
de7dabb6
TC
2172 && ckWARN(WARN_CLOSED)
2173 && type != OP_GLOB)
041457d9 2174 {
de7dabb6 2175 report_evil_fh(PL_last_in_gv);
3f4520fe 2176 }
54310121 2177 if (gimme == G_SCALAR) {
79628082 2178 /* undef TARG, and push that undefined value */
ba92458f 2179 if (type != OP_RCATLINE) {
aab1202a 2180 sv_setsv(TARG,NULL);
ba92458f 2181 }
a0d0e21e
LW
2182 PUSHTARG;
2183 }
2184 RETURN;
2185 }
a2008d6d 2186 have_fp:
54310121 2187 if (gimme == G_SCALAR) {
a0d0e21e 2188 sv = TARG;
0f722b55
RGS
2189 if (type == OP_RCATLINE && SvGMAGICAL(sv))
2190 mg_get(sv);
48de12d9
RGS
2191 if (SvROK(sv)) {
2192 if (type == OP_RCATLINE)
5668452f 2193 SvPV_force_nomg_nolen(sv);
48de12d9
RGS
2194 else
2195 sv_unref(sv);
2196 }
f7877b28 2197 else if (isGV_with_GP(sv)) {
5668452f 2198 SvPV_force_nomg_nolen(sv);
f7877b28 2199 }
862a34c6 2200 SvUPGRADE(sv, SVt_PV);
a0d0e21e 2201 tmplen = SvLEN(sv); /* remember if already alloced */
e3918bb7 2202 if (!tmplen && !SvREADONLY(sv) && !SvIsCOW(sv)) {
f72e8700
JJ
2203 /* try short-buffering it. Please update t/op/readline.t
2204 * if you change the growth length.
2205 */
2206 Sv_Grow(sv, 80);
2207 }
2b5e58c4
AMS
2208 offset = 0;
2209 if (type == OP_RCATLINE && SvOK(sv)) {
2210 if (!SvPOK(sv)) {
5668452f 2211 SvPV_force_nomg_nolen(sv);
2b5e58c4 2212 }
a0d0e21e 2213 offset = SvCUR(sv);
2b5e58c4 2214 }
a0d0e21e 2215 }
54310121 2216 else {
561b68a9 2217 sv = sv_2mortal(newSV(80));
54310121
PP
2218 offset = 0;
2219 }
fbad3eb5 2220
3887d568
AP
2221 /* This should not be marked tainted if the fp is marked clean */
2222#define MAYBE_TAINT_LINE(io, sv) \
2223 if (!(IoFLAGS(io) & IOf_UNTAINT)) { \
2224 TAINT; \
2225 SvTAINTED_on(sv); \
2226 }
2227
684bef36 2228/* delay EOF state for a snarfed empty file */
fbad3eb5 2229#define SNARF_EOF(gimme,rs,io,sv) \
684bef36 2230 (gimme != G_SCALAR || SvCUR(sv) \
b9fee9ba 2231 || (IoFLAGS(io) & IOf_NOLINE) || !RsSNARF(rs))
fbad3eb5 2232
a0d0e21e 2233 for (;;) {
09e8efcc 2234 PUTBACK;
fbad3eb5 2235 if (!sv_gets(sv, fp, offset)
2d726892
TF
2236 && (type == OP_GLOB
2237 || SNARF_EOF(gimme, PL_rs, io, sv)
2238 || PerlIO_error(fp)))
fbad3eb5 2239 {
760ac839 2240 PerlIO_clearerr(fp);
a0d0e21e 2241 if (IoFLAGS(io) & IOf_ARGV) {
157fb5a1 2242 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
a0d0e21e
LW
2243 if (fp)
2244 continue;
3280af22 2245 (void)do_close(PL_last_in_gv, FALSE);
a0d0e21e
LW
2246 }
2247 else if (type == OP_GLOB) {
a2a5de95
NC
2248 if (!do_close(PL_last_in_gv, FALSE)) {
2249 Perl_ck_warner(aTHX_ packWARN(WARN_GLOB),
2250 "glob failed (child exited with status %d%s)",
2251 (int)(STATUS_CURRENT >> 8),
2252 (STATUS_CURRENT & 0x80) ? ", core dumped" : "");
4eb79ab5 2253 }
a0d0e21e 2254 }
54310121 2255 if (gimme == G_SCALAR) {
ba92458f
AE
2256 if (type != OP_RCATLINE) {
2257 SV_CHECK_THINKFIRST_COW_DROP(TARG);
0c34ef67 2258 SvOK_off(TARG);
ba92458f 2259 }
09e8efcc 2260 SPAGAIN;
a0d0e21e
LW
2261 PUSHTARG;
2262 }
3887d568 2263 MAYBE_TAINT_LINE(io, sv);
a0d0e21e
LW
2264 RETURN;
2265 }
3887d568 2266 MAYBE_TAINT_LINE(io, sv);
a0d0e21e 2267 IoLINES(io)++;
b9fee9ba 2268 IoFLAGS(io) |= IOf_NOLINE;
71be2cbc 2269 SvSETMAGIC(sv);
09e8efcc 2270 SPAGAIN;
a0d0e21e 2271 XPUSHs(sv);
a0d0e21e 2272 if (type == OP_GLOB) {
349d4f2f 2273 const char *t1;
45a23732 2274 Stat_t statbuf;
a0d0e21e 2275
3280af22 2276 if (SvCUR(sv) > 0 && SvCUR(PL_rs) > 0) {
6136c704 2277 char * const tmps = SvEND(sv) - 1;
aa07b2f6 2278 if (*tmps == *SvPVX_const(PL_rs)) {
c07a80fd 2279 *tmps = '\0';
b162af07 2280 SvCUR_set(sv, SvCUR(sv) - 1);
c07a80fd
PP
2281 }
2282 }
349d4f2f 2283 for (t1 = SvPVX_const(sv); *t1; t1++)
b51c3e77
CB
2284#ifdef __VMS
2285 if (strchr("*%?", *t1))
2286#else
7ad1e72d 2287 if (strchr("$&*(){}[]'\";\\|?<>~`", *t1))
b51c3e77 2288#endif
a0d0e21e 2289 break;
45a23732 2290 if (*t1 && PerlLIO_lstat(SvPVX_const(sv), &statbuf) < 0) {
a0d0e21e
LW
2291 (void)POPs; /* Unmatched wildcard? Chuck it... */
2292 continue;
2293 }
2d79bf7f 2294 } else if (SvUTF8(sv)) { /* OP_READLINE, OP_RCATLINE */
d4c19fe8
AL
2295 if (ckWARN(WARN_UTF8)) {
2296 const U8 * const s = (const U8*)SvPVX_const(sv) + offset;
2297 const STRLEN len = SvCUR(sv) - offset;
2298 const U8 *f;
2299
2300 if (!is_utf8_string_loc(s, len, &f))
2301 /* Emulate :encoding(utf8) warning in the same case. */
2302 Perl_warner(aTHX_ packWARN(WARN_UTF8),
2303 "utf8 \"\\x%02X\" does not map to Unicode",
2304 f < (U8*)SvEND(sv) ? *f : 0);
2305 }
a0d0e21e 2306 }
54310121 2307 if (gimme == G_ARRAY) {
a0d0e21e 2308 if (SvLEN(sv) - SvCUR(sv) > 20) {
1da4ca5f 2309 SvPV_shrink_to_cur(sv);
a0d0e21e 2310 }
561b68a9 2311 sv = sv_2mortal(newSV(80));
a0d0e21e
LW
2312 continue;
2313 }
54310121 2314 else if (gimme == G_SCALAR && !tmplen && SvLEN(sv) - SvCUR(sv) > 80) {
a0d0e21e 2315 /* try to reclaim a bit of scalar space (only on 1st alloc) */
d5b5861b
NC
2316 const STRLEN new_len
2317 = SvCUR(sv) < 60 ? 80 : SvCUR(sv)+40; /* allow some slop */
1da4ca5f 2318 SvPV_renew(sv, new_len);
a0d0e21e
LW
2319 }
2320 RETURN;
2321 }
2322}
2323
a0d0e21e
LW
2324PP(pp_helem)
2325{
20b7effb 2326 dSP;
760ac839 2327 HE* he;
ae77835f 2328 SV **svp;
c445ea15 2329 SV * const keysv = POPs;
85fbaab2 2330 HV * const hv = MUTABLE_HV(POPs);
a3b680e6
AL
2331 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2332 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
be6c24e0 2333 SV *sv;
92970b93 2334 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
d30e492c 2335 bool preeminent = TRUE;
a0d0e21e 2336
6dfc73ea
SM
2337 if (SvTYPE(hv) != SVt_PVHV)
2338 RETPUSHUNDEF;
d4c19fe8 2339
92970b93 2340 if (localizing) {
d4c19fe8
AL
2341 MAGIC *mg;
2342 HV *stash;
d30e492c
VP
2343
2344 /* If we can determine whether the element exist,
2345 * Try to preserve the existenceness of a tied hash
2346 * element by using EXISTS and DELETE if possible.
2347 * Fallback to FETCH and STORE otherwise. */
2c5f48c2 2348 if (SvCANEXISTDELETE(hv))
d30e492c 2349 preeminent = hv_exists_ent(hv, keysv, 0);
d4c19fe8 2350 }
d30e492c 2351
5f9d7e2b 2352 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
d4c19fe8 2353 svp = he ? &HeVAL(he) : NULL;
a0d0e21e 2354 if (lval) {
746f6409 2355 if (!svp || !*svp || *svp == &PL_sv_undef) {
68dc0745
PP
2356 SV* lv;
2357 SV* key2;
2d8e6c8d 2358 if (!defer) {
be2597df 2359 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2d8e6c8d 2360 }
68dc0745
PP
2361 lv = sv_newmortal();
2362 sv_upgrade(lv, SVt_PVLV);
2363 LvTYPE(lv) = 'y';
6136c704 2364 sv_magic(lv, key2 = newSVsv(keysv), PERL_MAGIC_defelem, NULL, 0);
fc2b2dca 2365 SvREFCNT_dec_NN(key2); /* sv_magic() increments refcount */
0ad694a7 2366 LvTARG(lv) = SvREFCNT_inc_simple_NN(hv);
68dc0745
PP
2367 LvTARGLEN(lv) = 1;
2368 PUSHs(lv);
2369 RETURN;
2370 }
92970b93 2371 if (localizing) {
bfcb3514 2372 if (HvNAME_get(hv) && isGV(*svp))
159b6efe 2373 save_gp(MUTABLE_GV(*svp), !(PL_op->op_flags & OPf_SPECIAL));
47cfc530
VP
2374 else if (preeminent)
2375 save_helem_flags(hv, keysv, svp,
2376 (PL_op->op_flags & OPf_SPECIAL) ? 0 : SAVEf_SETMAGIC);
2377 else
2378 SAVEHDELETE(hv, keysv);
5f05dabc 2379 }
9026059d
GG
2380 else if (PL_op->op_private & OPpDEREF) {
2381 PUSHs(vivify_ref(*svp, PL_op->op_private & OPpDEREF));
2382 RETURN;
2383 }
a0d0e21e 2384 }
746f6409 2385 sv = (svp && *svp ? *svp : &PL_sv_undef);
fd69380d
DM
2386 /* Originally this did a conditional C<sv = sv_mortalcopy(sv)>; this
2387 * was to make C<local $tied{foo} = $tied{foo}> possible.
2388 * However, it seems no longer to be needed for that purpose, and
2389 * introduced a new bug: stuff like C<while ($hash{taintedval} =~ /.../g>
2390 * would loop endlessly since the pos magic is getting set on the
2391 * mortal copy and lost. However, the copy has the effect of
2392 * triggering the get magic, and losing it altogether made things like
2393 * c<$tied{foo};> in void context no longer do get magic, which some
2394 * code relied on. Also, delayed triggering of magic on @+ and friends
2395 * meant the original regex may be out of scope by now. So as a
2396 * compromise, do the get magic here. (The MGf_GSKIP flag will stop it
2397 * being called too many times). */
39cf747a 2398 if (!lval && SvRMAGICAL(hv) && SvGMAGICAL(sv))
fd69380d 2399 mg_get(sv);
be6c24e0 2400 PUSHs(sv);
a0d0e21e
LW
2401 RETURN;
2402}
2403
fedf30e1
DM
2404
2405/* a stripped-down version of Perl_softref2xv() for use by
2406 * pp_multideref(), which doesn't use PL_op->op_flags */
2407
f9db5646 2408STATIC GV *
fedf30e1
DM
2409S_softref2xv_lite(pTHX_ SV *const sv, const char *const what,
2410 const svtype type)
2411{
2412 if (PL_op->op_private & HINT_STRICT_REFS) {
2413 if (SvOK(sv))
2414 Perl_die(aTHX_ PL_no_symref_sv, sv,
2415 (SvPOKp(sv) && SvCUR(sv)>32 ? "..." : ""), what);
2416 else
2417 Perl_die(aTHX_ PL_no_usym, what);
2418 }
2419 if (!SvOK(sv))
2420 Perl_die(aTHX_ PL_no_usym, what);
2421 return gv_fetchsv_nomg(sv, GV_ADD, type);
2422}
2423
2424
79815f56
DM
2425/* Handle one or more aggregate derefs and array/hash indexings, e.g.
2426 * $h->{foo} or $a[0]{$key}[$i] or f()->[1]
fedf30e1
DM
2427 *
2428 * op_aux points to an array of unions of UV / IV / SV* / PADOFFSET.
79815f56
DM
2429 * Each of these either contains a set of actions, or an argument, such as
2430 * an IV to use as an array index, or a lexical var to retrieve.
2431 * Several actions re stored per UV; we keep shifting new actions off the
2432 * one UV, and only reload when it becomes zero.
fedf30e1
DM
2433 */
2434
2435PP(pp_multideref)
2436{
2437 SV *sv = NULL; /* init to avoid spurious 'may be used uninitialized' */
2438 UNOP_AUX_item *items = cUNOP_AUXx(PL_op)->op_aux;
2439 UV actions = items->uv;
2440
2441 assert(actions);
2442 /* this tells find_uninit_var() where we're up to */
2443 PL_multideref_pc = items;
2444
2445 while (1) {
2446 /* there are three main classes of action; the first retrieve
2447 * the initial AV or HV from a variable or the stack; the second
2448 * does the equivalent of an unrolled (/DREFAV, rv2av, aelem),
2449 * the third an unrolled (/DREFHV, rv2hv, helem).
2450 */
2451 switch (actions & MDEREF_ACTION_MASK) {
2452
2453 case MDEREF_reload:
2454 actions = (++items)->uv;
2455 continue;
2456
2457 case MDEREF_AV_padav_aelem: /* $lex[...] */
2458 sv = PAD_SVl((++items)->pad_offset);
2459 goto do_AV_aelem;
2460
2461 case MDEREF_AV_gvav_aelem: /* $pkg[...] */
2462 sv = UNOP_AUX_item_sv(++items);
2463 assert(isGV_with_GP(sv));
2464 sv = (SV*)GvAVn((GV*)sv);
2465 goto do_AV_aelem;
2466
2467 case MDEREF_AV_pop_rv2av_aelem: /* expr->[...] */
2468 {
2469 dSP;
2470 sv = POPs;
2471 PUTBACK;
2472 goto do_AV_rv2av_aelem;
2473 }
2474
2475 case MDEREF_AV_gvsv_vivify_rv2av_aelem: /* $pkg->[...] */
2476 sv = UNOP_AUX_item_sv(++items);
2477 assert(isGV_with_GP(sv));
2478 sv = GvSVn((GV*)sv);
2479 goto do_AV_vivify_rv2av_aelem;
2480
2481 case MDEREF_AV_padsv_vivify_rv2av_aelem: /* $lex->[...] */
2482 sv = PAD_SVl((++items)->pad_offset);
2483 /* FALLTHROUGH */
2484
2485 do_AV_vivify_rv2av_aelem:
2486 case MDEREF_AV_vivify_rv2av_aelem: /* vivify, ->[...] */
2487 /* this is the OPpDEREF action normally found at the end of
2488 * ops like aelem, helem, rv2sv */
2489 sv = vivify_ref(sv, OPpDEREF_AV);
2490 /* FALLTHROUGH */
2491
2492 do_AV_rv2av_aelem:
2493 /* this is basically a copy of pp_rv2av when it just has the
2494 * sKR/1 flags */
2495 SvGETMAGIC(sv);
2496 if (LIKELY(SvROK(sv))) {
2497 if (UNLIKELY(SvAMAGIC(sv))) {
2498 sv = amagic_deref_call(sv, to_av_amg);
2499 }
2500 sv = SvRV(sv);
2501 if (UNLIKELY(SvTYPE(sv) != SVt_PVAV))
2502 DIE(aTHX_ "Not an ARRAY reference");
2503 }
2504 else if (SvTYPE(sv) != SVt_PVAV) {
2505 if (!isGV_with_GP(sv))
2506 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "an ARRAY", SVt_PVAV);
2507 sv = MUTABLE_SV(GvAVn((GV*)sv));
2508 }
2509 /* FALLTHROUGH */
2510
2511 do_AV_aelem:
2512 {
2513 /* retrieve the key; this may be either a lexical or package
2514 * var (whose index/ptr is stored as an item) or a signed
2515 * integer constant stored as an item.
2516 */
2517 SV *elemsv;
2518 IV elem = 0; /* to shut up stupid compiler warnings */
2519
2520
2521 assert(SvTYPE(sv) == SVt_PVAV);
2522
2523 switch (actions & MDEREF_INDEX_MASK) {
2524 case MDEREF_INDEX_none:
2525 goto finish;
2526 case MDEREF_INDEX_const:
2527 elem = (++items)->iv;
2528 break;
2529 case MDEREF_INDEX_padsv:
2530 elemsv = PAD_SVl((++items)->pad_offset);
2531 goto check_elem;
2532 case MDEREF_INDEX_gvsv:
2533 elemsv = UNOP_AUX_item_sv(++items);
2534 assert(isGV_with_GP(elemsv));
2535 elemsv = GvSVn((GV*)elemsv);
2536 check_elem:
2537 if (UNLIKELY(SvROK(elemsv) && !SvGAMAGIC(elemsv)
2538 && ckWARN(WARN_MISC)))
2539 Perl_warner(aTHX_ packWARN(WARN_MISC),
147e3846 2540 "Use of reference \"%" SVf "\" as array index",
fedf30e1
DM
2541 SVfARG(elemsv));
2542 /* the only time that S_find_uninit_var() needs this
2543 * is to determine which index value triggered the
2544 * undef warning. So just update it here. Note that
2545 * since we don't save and restore this var (e.g. for
2546 * tie or overload execution), its value will be
2547 * meaningless apart from just here */
2548 PL_multideref_pc = items;
2549 elem = SvIV(elemsv);
2550 break;
2551 }
2552
2553
2554 /* this is basically a copy of pp_aelem with OPpDEREF skipped */
2555
2556 if (!(actions & MDEREF_FLAG_last)) {
2557 SV** svp = av_fetch((AV*)sv, elem, 1);
2558 if (!svp || ! (sv=*svp))
2559 DIE(aTHX_ PL_no_aelem, elem);
2560 break;
2561 }
2562
2563 if (PL_op->op_private &
2564 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
2565 {
2566 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
2567 sv = av_exists((AV*)sv, elem) ? &PL_sv_yes : &PL_sv_no;
2568 }
2569 else {
2570 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
2571 sv = av_delete((AV*)sv, elem, discard);
2572 if (discard)
2573 return NORMAL;
2574 if (!sv)
2575 sv = &PL_sv_undef;
2576 }
2577 }
2578 else {
2579 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2580 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
2581 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
2582 bool preeminent = TRUE;
2583 AV *const av = (AV*)sv;
2584 SV** svp;
2585
2586 if (UNLIKELY(localizing)) {
2587 MAGIC *mg;
2588 HV *stash;
2589
2590 /* If we can determine whether the element exist,
2591 * Try to preserve the existenceness of a tied array
2592 * element by using EXISTS and DELETE if possible.
2593 * Fallback to FETCH and STORE otherwise. */
2594 if (SvCANEXISTDELETE(av))
2595 preeminent = av_exists(av, elem);
2596 }
2597
2598 svp = av_fetch(av, elem, lval && !defer);
2599
2600 if (lval) {
2601 if (!svp || !(sv = *svp)) {
2602 IV len;
2603 if (!defer)
2604 DIE(aTHX_ PL_no_aelem, elem);
2605 len = av_tindex(av);
2606 sv = sv_2mortal(newSVavdefelem(av,
2607 /* Resolve a negative index now, unless it points
2608 * before the beginning of the array, in which
2609 * case record it for error reporting in
2610 * magic_setdefelem. */
2611 elem < 0 && len + elem >= 0
2612 ? len + elem : elem, 1));
2613 }
2614 else {
2615 if (UNLIKELY(localizing)) {
2616 if (preeminent) {
2617 save_aelem(av, elem, svp);
2618 sv = *svp; /* may have changed */
2619 }
2620 else
2621 SAVEADELETE(av, elem);
2622 }
2623 }
2624 }
2625 else {
2626 sv = (svp ? *svp : &PL_sv_undef);
2627 /* see note in pp_helem() */
2628 if (SvRMAGICAL(av) && SvGMAGICAL(sv))
2629 mg_get(sv);
2630 }
2631 }
2632
2633 }
2634 finish:
2635 {
2636 dSP;
2637 XPUSHs(sv);
2638 RETURN;
2639 }
2640 /* NOTREACHED */
2641
2642
2643
2644
2645 case MDEREF_HV_padhv_helem: /* $lex{...} */
2646 sv = PAD_SVl((++items)->pad_offset);
2647 goto do_HV_helem;
2648
2649 case MDEREF_HV_gvhv_helem: /* $pkg{...} */
2650 sv = UNOP_AUX_item_sv(++items);
2651 assert(isGV_with_GP(sv));
2652 sv = (SV*)GvHVn((GV*)sv);
2653 goto do_HV_helem;
2654
2655 case MDEREF_HV_pop_rv2hv_helem: /* expr->{...} */
2656 {
2657 dSP;
2658 sv = POPs;
2659 PUTBACK;
2660 goto do_HV_rv2hv_helem;
2661 }
2662
2663 case MDEREF_HV_gvsv_vivify_rv2hv_helem: /* $pkg->{...} */
2664 sv = UNOP_AUX_item_sv(++items);
2665 assert(isGV_with_GP(sv));
2666 sv = GvSVn((GV*)sv);
2667 goto do_HV_vivify_rv2hv_helem;
2668
2669 case MDEREF_HV_padsv_vivify_rv2hv_helem: /* $lex->{...} */
2670 sv = PAD_SVl((++items)->pad_offset);
2671 /* FALLTHROUGH */
2672
2673 do_HV_vivify_rv2hv_helem:
2674 case MDEREF_HV_vivify_rv2hv_helem: /* vivify, ->{...} */
2675 /* this is the OPpDEREF action normally found at the end of
2676 * ops like aelem, helem, rv2sv */
2677 sv = vivify_ref(sv, OPpDEREF_HV);
2678 /* FALLTHROUGH */
2679
2680 do_HV_rv2hv_helem:
2681 /* this is basically a copy of pp_rv2hv when it just has the
2682 * sKR/1 flags (and pp_rv2hv is aliased to pp_rv2av) */
2683
2684 SvGETMAGIC(sv);
2685 if (LIKELY(SvROK(sv))) {
2686 if (UNLIKELY(SvAMAGIC(sv))) {
2687 sv = amagic_deref_call(sv, to_hv_amg);
2688 }
2689 sv = SvRV(sv);
2690 if (UNLIKELY(SvTYPE(sv) != SVt_PVHV))
2691 DIE(aTHX_ "Not a HASH reference");
2692 }
2693 else if (SvTYPE(sv) != SVt_PVHV) {
2694 if (!isGV_with_GP(sv))
2695 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "a HASH", SVt_PVHV);
2696 sv = MUTABLE_SV(GvHVn((GV*)sv));
2697 }
2698 /* FALLTHROUGH */
2699
2700 do_HV_helem:
2701 {
2702 /* retrieve the key; this may be either a lexical / package
2703 * var or a string constant, whose index/ptr is stored as an
2704 * item
2705 */
2706 SV *keysv = NULL; /* to shut up stupid compiler warnings */
2707
2708 assert(SvTYPE(sv) == SVt_PVHV);
2709
2710 switch (actions & MDEREF_INDEX_MASK) {
2711 case MDEREF_INDEX_none:
2712 goto finish;
2713
2714 case MDEREF_INDEX_const:
2715 keysv = UNOP_AUX_item_sv(++items);
2716 break;
2717
2718 case MDEREF_INDEX_padsv:
2719 keysv = PAD_SVl((++items)->pad_offset);
2720 break;
2721
2722 case MDEREF_INDEX_gvsv:
2723 keysv = UNOP_AUX_item_sv(++items);
2724 keysv = GvSVn((GV*)keysv);
2725 break;
2726 }
2727
2728 /* see comment above about setting this var */
2729 PL_multideref_pc = items;
2730
2731
2732 /* ensure that candidate CONSTs have been HEKified */
2733 assert( ((actions & MDEREF_INDEX_MASK) != MDEREF_INDEX_const)
2734 || SvTYPE(keysv) >= SVt_PVMG
2735 || !SvOK(keysv)
2736 || SvROK(keysv)
2737 || SvIsCOW_shared_hash(keysv));
2738
2739 /* this is basically a copy of pp_helem with OPpDEREF skipped */
2740
2741 if (!(actions & MDEREF_FLAG_last)) {
2742 HE *he = hv_fetch_ent((HV*)sv, keysv, 1, 0);
2743 if (!he || !(sv=HeVAL(he)) || sv == &PL_sv_undef)
2744 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2745 break;
2746 }
2747
2748 if (PL_op->op_private &
2749 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
2750 {
2751 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
2752 sv = hv_exists_ent((HV*)sv, keysv, 0)
2753 ? &PL_sv_yes : &PL_sv_no;
2754 }
2755 else {
2756 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
2757 sv = hv_delete_ent((HV*)sv, keysv, discard, 0);
2758 if (discard)
2759 return NORMAL;
2760 if (!sv)
2761 sv = &PL_sv_undef;
2762 }
2763 }
2764 else {
2765 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2766 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
2767 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
2768 bool preeminent = TRUE;
2769 SV **svp;
2770 HV * const hv = (HV*)sv;
2771 HE* he;
2772
2773 if (UNLIKELY(localizing)) {
2774 MAGIC *mg;
2775 HV *stash;
2776
2777 /* If we can determine whether the element exist,
2778 * Try to preserve the existenceness of a tied hash
2779 * element by using EXISTS and DELETE if possible.
2780 * Fallback to FETCH and STORE otherwise. */
2781 if (SvCANEXISTDELETE(hv))
2782 preeminent = hv_exists_ent(hv, keysv, 0);
2783 }
2784
2785 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
2786 svp = he ? &HeVAL(he) : NULL;
2787
2788
2789 if (lval) {
2790 if (!svp || !(sv = *svp) || sv == &PL_sv_undef) {
2791 SV* lv;
2792 SV* key2;
2793 if (!defer)
2794 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2795 lv = sv_newmortal();
2796 sv_upgrade(lv, SVt_PVLV);
2797 LvTYPE(lv) = 'y';
2798 sv_magic(lv, key2 = newSVsv(keysv),
2799 PERL_MAGIC_defelem, NULL, 0);
2800 /* sv_magic() increments refcount */
2801 SvREFCNT_dec_NN(key2);
0ad694a7 2802 LvTARG(lv) = SvREFCNT_inc_simple_NN(hv);
fedf30e1
DM
2803 LvTARGLEN(lv) = 1;
2804 sv = lv;
2805 }
2806 else {
2807 if (localizing) {
2808 if (HvNAME_get(hv) && isGV(sv))
2809 save_gp(MUTABLE_GV(sv),
2810 !(PL_op->op_flags & OPf_SPECIAL));
2811 else if (preeminent) {
2812 save_helem_flags(hv, keysv, svp,
2813 (PL_op->op_flags & OPf_SPECIAL)
2814 ? 0 : SAVEf_SETMAGIC);
2815 sv = *svp; /* may have changed */
2816 }
2817 else
2818 SAVEHDELETE(hv, keysv);
2819 }
2820 }
2821 }
2822 else {
2823 sv = (svp && *svp ? *svp : &PL_sv_undef);
2824 /* see note in pp_helem() */
2825 if (SvRMAGICAL(hv) && SvGMAGICAL(sv))
2826 mg_get(sv);
2827 }
2828 }
2829 goto finish;
2830 }
2831
2832 } /* switch */
2833
2834 actions >>= MDEREF_SHIFT;
2835 } /* while */
2836 /* NOTREACHED */
2837}
2838
2839
a0d0e21e
LW
2840PP(pp_iter)
2841{
eb578fdb 2842 PERL_CONTEXT *cx;
7d6c2cef 2843 SV *oldsv;
1d7c1841 2844 SV **itersvp;
8a1f10dd 2845 SV *retsv;
a0d0e21e 2846
84f05d57
JH
2847 SV *sv;
2848 AV *av;
2849 IV ix;
2850 IV inc;
2851
4ebe6e95 2852 cx = CX_CUR();
1d7c1841 2853 itersvp = CxITERVAR(cx);
4b5c941e 2854 assert(itersvp);
a48ce6be
DM
2855
2856 switch (CxTYPE(cx)) {
17c91640 2857
b552b52c
DM
2858 case CXt_LOOP_LAZYSV: /* string increment */
2859 {
2860 SV* cur = cx->blk_loop.state_u.lazysv.cur;
2861 SV *end = cx->blk_loop.state_u.lazysv.end;
2862 /* If the maximum is !SvOK(), pp_enteriter substitutes PL_sv_no.
2863 It has SvPVX of "" and SvCUR of 0, which is what we want. */
2864 STRLEN maxlen = 0;
2865 const char *max = SvPV_const(end, maxlen);
5d9574c1 2866 if (UNLIKELY(SvNIOK(cur) || SvCUR(cur) > maxlen))
8a1f10dd 2867 goto retno;
b552b52c
DM
2868
2869 oldsv = *itersvp;
6d3ca00e
DM
2870 /* NB: on the first iteration, oldsv will have a ref count of at
2871 * least 2 (one extra from blk_loop.itersave), so the GV or pad
2872 * slot will get localised; on subsequent iterations the RC==1
2873 * optimisation may kick in and the SV will be reused. */
2874 if (oldsv && LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
b552b52c
DM
2875 /* safe to reuse old SV */
2876 sv_setsv(oldsv, cur);
a48ce6be 2877 }
b552b52c
DM
2878 else
2879 {
2880 /* we need a fresh SV every time so that loop body sees a
2881 * completely new SV for closures/references to work as
2882 * they used to */
2883 *itersvp = newSVsv(cur);
6d3ca00e 2884 SvREFCNT_dec(oldsv);
b552b52c
DM
2885 }
2886 if (strEQ(SvPVX_const(cur), max))
2887 sv_setiv(cur, 0); /* terminate next time */
2888 else
2889 sv_inc(cur);
2890 break;
2891 }
a48ce6be 2892
fcef60b4
DM
2893 case CXt_LOOP_LAZYIV: /* integer increment */
2894 {
2895 IV cur = cx->blk_loop.state_u.lazyiv.cur;
5d9574c1 2896 if (UNLIKELY(cur > cx->blk_loop.state_u.lazyiv.end))
8a1f10dd 2897 goto retno;
7f61b687 2898
fcef60b4 2899 oldsv = *itersvp;
6d3ca00e
DM
2900 /* see NB comment above */
2901 if (oldsv && LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
eaa5c2d6 2902 /* safe to reuse old SV */
47b96a1e
DM
2903
2904 if ( (SvFLAGS(oldsv) & (SVTYPEMASK|SVf_THINKFIRST|SVf_IVisUV))
2905 == SVt_IV)
2906 {
2907 /* Cheap SvIOK_only().
2908 * Assert that flags which SvIOK_only() would test or
2909 * clear can't be set, because we're SVt_IV */
2910 assert(!(SvFLAGS(oldsv) &
2911 (SVf_OOK|SVf_UTF8|(SVf_OK & ~(SVf_IOK|SVp_IOK)))));
2912 SvFLAGS(oldsv) |= (SVf_IOK|SVp_IOK);
2913 /* SvIV_set() where sv_any points to head */
2914 oldsv->sv_u.svu_iv = cur;
2915
2916 }
2917 else
2918 sv_setiv(oldsv, cur);
eaa5c2d6 2919 }
1c846c1f 2920 else
eaa5c2d6
GA
2921 {
2922 /* we need a fresh SV every time so that loop body sees a
2923 * completely new SV for closures/references to work as they
2924 * used to */
fcef60b4 2925 *itersvp = newSViv(cur);
6d3ca00e 2926 SvREFCNT_dec(oldsv);
eaa5c2d6 2927 }
a2309040 2928
5d9574c1 2929 if (UNLIKELY(cur == IV_MAX)) {
cdc1aa42
NC
2930 /* Handle end of range at IV_MAX */
2931 cx->blk_loop.state_u.lazyiv.end = IV_MIN;
2932 } else
2933 ++cx->blk_loop.state_u.lazyiv.cur;
a48ce6be 2934 break;
fcef60b4 2935 }
a48ce6be 2936
93661e56
DM
2937 case CXt_LOOP_LIST: /* for (1,2,3) */
2938
2939 assert(OPpITER_REVERSED == 2); /* so inc becomes -1 or 1 */
2940 inc = 1 - (PL_op->op_private & OPpITER_REVERSED);
2941 ix = (cx->blk_loop.state_u.stack.ix += inc);
2942 if (UNLIKELY(inc > 0
2943 ? ix > cx->blk_oldsp
2944 : ix <= cx->blk_loop.state_u.stack.basesp)
2945 )
8a1f10dd 2946 goto retno;
93661e56
DM
2947
2948 sv = PL_stack_base[ix];
2949 av = NULL;
2950 goto loop_ary_common;
2951
2952 case CXt_LOOP_ARY: /* for (@ary) */
2953
2954 av = cx->blk_loop.state_u.ary.ary;
2955 inc = 1 - (PL_op->op_private & OPpITER_REVERSED);
2956 ix = (cx->blk_loop.state_u.ary.ix += inc);
2957 if (UNLIKELY(inc > 0
2958 ? ix > AvFILL(av)
2959 : ix < 0)
2960 )
8a1f10dd 2961 goto retno;
de080daa 2962
9d1ee8e0 2963 if (UNLIKELY(SvRMAGICAL(av))) {
a8a20bb6
DM
2964 SV * const * const svp = av_fetch(av, ix, FALSE);
2965 sv = svp ? *svp : NULL;
2966 }
2967 else {
2968 sv = AvARRAY(av)[ix];
de080daa 2969 }
ef3e5ea9 2970
93661e56
DM
2971 loop_ary_common:
2972
d39c26a6
FC
2973 if (UNLIKELY(cx->cx_type & CXp_FOR_LVREF)) {
2974 SvSetMagicSV(*itersvp, sv);
2975 break;
2976 }
2977
5d9574c1
DM
2978 if (LIKELY(sv)) {
2979 if (UNLIKELY(SvIS_FREED(sv))) {
f38aa882
DM
2980 *itersvp = NULL;
2981 Perl_croak(aTHX_ "Use of freed value in iteration");
2982 }
60779a30 2983 if (SvPADTMP(sv)) {
8e079c2a 2984 sv = newSVsv(sv);
60779a30 2985 }
8e079c2a
FC
2986 else {
2987 SvTEMP_off(sv);
2988 SvREFCNT_inc_simple_void_NN(sv);
2989 }
de080daa 2990 }
93661e56 2991 else if (av) {
199f858d 2992 sv = newSVavdefelem(av, ix, 0);
de080daa 2993 }
a600f7e6
FC
2994 else
2995 sv = &PL_sv_undef;
a0d0e21e 2996
de080daa
DM
2997 oldsv = *itersvp;
2998 *itersvp = sv;
2999 SvREFCNT_dec(oldsv);
de080daa 3000 break;
a48ce6be
DM
3001
3002 default:
3003 DIE(aTHX_ "panic: pp_iter, type=%u", CxTYPE(cx));
3004 }
8a1f10dd
DM
3005
3006 retsv = &PL_sv_yes;
3007 if (0) {
3008 retno:
3009 retsv = &PL_sv_no;
3010 }
3011 /* pp_enteriter should have pre-extended the stack */
3012 assert(PL_stack_sp < PL_stack_max);
3013 *++PL_stack_sp =retsv;
3014
3015 return PL_op->op_next;
a0d0e21e
LW
3016}
3017
ef07e810
DM
3018/*
3019A description of how taint works in pattern matching and substitution.
3020
284167a5
SM
3021This is all conditional on NO_TAINT_SUPPORT not being defined. Under
3022NO_TAINT_SUPPORT, taint-related operations should become no-ops.
3023
4e19c54b 3024While the pattern is being assembled/concatenated and then compiled,
284167a5
SM
3025PL_tainted will get set (via TAINT_set) if any component of the pattern
3026is tainted, e.g. /.*$tainted/. At the end of pattern compilation,
3027the RXf_TAINTED flag is set on the pattern if PL_tainted is set (via
1738e041
DM
3028TAINT_get). It will also be set if any component of the pattern matches
3029based on locale-dependent behavior.
ef07e810 3030
0ab462a6
DM
3031When the pattern is copied, e.g. $r = qr/..../, the SV holding the ref to
3032the pattern is marked as tainted. This means that subsequent usage, such
284167a5
SM
3033as /x$r/, will set PL_tainted using TAINT_set, and thus RXf_TAINTED,
3034on the new pattern too.
ef07e810 3035
272d35c9 3036RXf_TAINTED_SEEN is used post-execution by the get magic code
ef07e810
DM
3037of $1 et al to indicate whether the returned value should be tainted.
3038It is the responsibility of the caller of the pattern (i.e. pp_match,
3039pp_subst etc) to set this flag for any other circumstances where $1 needs
3040to be tainted.
3041
3042The taint behaviour of pp_subst (and pp_substcont) is quite complex.
3043
3044There are three possible sources of taint
3045 * the source string
3046 * the pattern (both compile- and run-time, RXf_TAINTED / RXf_TAINTED_SEEN)
3047 * the replacement string (or expression under /e)
3048
3049There are four destinations of taint and they are affected by the sources
3050according to the rules below:
3051
3052 * the return value (not including /r):
3053 tainted by the source string and pattern, but only for the
3054 number-of-iterations case; boolean returns aren't tainted;
3055 * the modified string (or modified copy under /r):
3056 tainted by the source string, pattern, and replacement strings;
3057 * $1 et al:
3058 tainted by the pattern, and under 'use re "taint"', by the source
3059 string too;
3060 * PL_taint - i.e. whether subsequent code (e.g. in a /e block) is tainted:
3061 should always be unset before executing subsequent code.
3062
3063The overall action of pp_subst is:
3064
3065 * at the start, set bits in rxtainted indicating the taint status of
3066 the various sources.
3067
3068 * After each pattern execution, update the SUBST_TAINT_PAT bit in
3069 rxtainted if RXf_TAINTED_SEEN has been set, to indicate that the
3070 pattern has subsequently become tainted via locale ops.
3071
3072 * If control is being passed to pp_substcont to execute a /e block,
3073 save rxtainted in the CXt_SUBST block, for future use by
3074 pp_substcont.
3075
3076 * Whenever control is being returned to perl code (either by falling
3077 off the "end" of pp_subst/pp_substcont, or by entering a /e block),
3078 use the flag bits in rxtainted to make all the appropriate types of
0ab462a6
DM
3079 destination taint visible; e.g. set RXf_TAINTED_SEEN so that $1
3080 et al will appear tainted.
ef07e810
DM
3081
3082pp_match is just a simpler version of the above.
3083
3084*/
3085
a0d0e21e
LW
3086PP(pp_subst)
3087{
20b7effb 3088 dSP; dTARG;
eb578fdb 3089 PMOP *pm = cPMOP;
a0d0e21e 3090 PMOP *rpm = pm;
eb578fdb 3091 char *s;
a0d0e21e 3092 char *strend;
5c144d81 3093 const char *c;
a0d0e21e 3094 STRLEN clen;
3c6ef0a5
FC
3095 SSize_t iters = 0;
3096 SSize_t maxiters;
a0d0e21e 3097 bool once;
ef07e810
DM
3098 U8 rxtainted = 0; /* holds various SUBST_TAINT_* flag bits.
3099 See "how taint works" above */
a0d0e21e 3100 char *orig;
1ed74d04 3101 U8 r_flags;
eb578fdb 3102 REGEXP *rx = PM_GETRE(pm);
a0d0e21e
LW
3103 STRLEN len;
3104 int force_on_match = 0;
0bcc34c2 3105 const I32 oldsave = PL_savestack_ix;
792b2c16 3106 STRLEN slen;
26a74523 3107 bool doutf8 = FALSE; /* whether replacement is in utf8 */
db2c6cb3 3108#ifdef PERL_ANY_COW
106d9a13 3109 bool was_cow;
ed252734 3110#endif
a0714e2c 3111 SV *nsv = NULL;
b770e143 3112 /* known replacement string? */
eb578fdb 3113 SV *dstr = (pm->op_pmflags & PMf_CONST) ? POPs : NULL;
a0d0e21e 3114
f410a211
NC
3115 PERL_ASYNC_CHECK();
3116
533c011a 3117 if (PL_op->op_flags & OPf_STACKED)
a0d0e21e 3118 TARG = POPs;
6ffceeb7 3119 else if (ARGTARG)
59f00321 3120 GETTARGET;
a0d0e21e 3121 else {
54b9620d 3122 TARG = DEFSV;
a0d0e21e 3123 EXTEND(SP,1);
1c846c1f 3124 }
d9f424b2 3125
64534138 3126 SvGETMAGIC(TARG); /* must come before cow check */
db2c6cb3 3127#ifdef PERL_ANY_COW
106d9a13
DM
3128 /* note that a string might get converted to COW during matching */
3129 was_cow = cBOOL(SvIsCOW(TARG));
ed252734 3130#endif
d13a5d3b
TC
3131 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
3132#ifndef PERL_ANY_COW
3133 if (SvIsCOW(TARG))
3134 sv_force_normal_flags(TARG,0);
3135#endif
3136 if ((SvREADONLY(TARG)
3137 || ( ((SvTYPE(TARG) == SVt_PVGV && isGV_with_GP(TARG))
3138 || SvTYPE(TARG) > SVt_PVLV)
3139 && !(SvTYPE(TARG) == SVt_PVGV && SvFAKE(TARG)))))
3140 Perl_croak_no_modify();
3141 }
8ec5e241
NIS
3142 PUTBACK;
3143
6ac6605d
DM
3144 orig = SvPV_nomg(TARG, len);
3145 /* note we don't (yet) force the var into being a string; if we fail
92711104 3146 * to match, we leave as-is; on successful match however, we *will*
6ac6605d 3147 * coerce into a string, then repeat the match */
4499db73 3148 if (!SvPOKp(TARG) || SvTYPE(TARG) == SVt_PVGV || SvVOK(TARG))
a0d0e21e 3149 force_on_match = 1;
20be6587
DM
3150
3151 /* only replace once? */
3152 once = !(rpm->op_pmflags & PMf_GLOBAL);
3153
ef07e810 3154 /* See "how taint works" above */
284167a5 3155 if (TAINTING_get) {
20be6587
DM
3156 rxtainted = (
3157 (SvTAINTED(TARG) ? SUBST_TAINT_STR : 0)
284167a5 3158 | (RX_ISTAINTED(rx) ? SUBST_TAINT_PAT : 0)
20be6587
DM
3159 | ((pm->op_pmflags & PMf_RETAINT) ? SUBST_TAINT_RETAINT : 0)
3160 | ((once && !(rpm->op_pmflags & PMf_NONDESTRUCT))
3161 ? SUBST_TAINT_BOOLRET : 0));
3162 TAINT_NOT;
3163 }
a12c0f56 3164
a0d0e21e 3165 force_it:
6ac6605d
DM
3166 if (!pm || !orig)
3167 DIE(aTHX_ "panic: pp_subst, pm=%p, orig=%p", pm, orig);
a0d0e21e 3168
6ac6605d
DM
3169 strend = orig + len;
3170 slen = DO_UTF8(TARG) ? utf8_length((U8*)orig, (U8*)strend) : len;
792b2c16
JH
3171 maxiters = 2 * slen + 10; /* We can match twice at each
3172 position, once with zero-length,
3173 second time with non-zero. */
a0d0e21e 3174
794826f4
YO
3175 /* handle the empty pattern */
3176 if (!RX_PRELEN(rx) && PL_curpm && !ReANY(rx)->mother_re) {
5585e758
YO
3177 if (PL_curpm == PL_reg_curpm) {
3178 if (PL_curpm_under) {
3179 if (PL_curpm_under == PL_reg_curpm) {
3180 Perl_croak(aTHX_ "Infinite recursion via empty pattern");
3181 } else {
3182 pm = PL_curpm_under;
3183 }
3184 }
3185 } else {
3186 pm = PL_curpm;
3187 }
3188 rx = PM_GETRE(pm);
a0d0e21e 3189 }
6502e081 3190
6e240d0b 3191#ifdef PERL_SAWAMPERSAND
6502e081
DM
3192 r_flags = ( RX_NPARENS(rx)
3193 || PL_sawampersand
6502e081 3194 || (RX_EXTFLAGS(rx) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
5b0e71e9 3195 || (rpm->op_pmflags & PMf_KEEPCOPY)
6502e081
DM
3196 )
3197 ? REXEC_COPY_STR
3198 : 0;
6e240d0b
FC
3199#else
3200 r_flags = REXEC_COPY_STR;
3201#endif
7fba1cd6 3202
0395280b 3203 if (!CALLREGEXEC(rx, orig, strend, orig, 0, TARG, NULL, r_flags))
8b64c330 3204 {
5e79dfb9
DM
3205 SPAGAIN;
3206 PUSHs(rpm->op_pmflags & PMf_NONDESTRUCT ? TARG : &PL_sv_no);
3207 LEAVE_SCOPE(oldsave);
3208 RETURN;
3209 }
1754320d
FC
3210 PL_curpm = pm;
3211
71be2cbc 3212 /* known replacement string? */
f272994b 3213 if (dstr) {
8514a05a
JH
3214 /* replacement needing upgrading? */
3215 if (DO_UTF8(TARG) && !doutf8) {
db79b45b 3216 nsv = sv_newmortal();
4a176938 3217 SvSetSV(nsv, dstr);
8df0e7a2 3218 sv_utf8_upgrade(nsv);
5c144d81 3219 c = SvPV_const(nsv, clen);
4a176938
JH
3220 doutf8 = TRUE;
3221 }
3222 else {
5c144d81 3223 c = SvPV_const(dstr, clen);
4a176938 3224 doutf8 = DO_UTF8(dstr);
8514a05a 3225 }
bb933b9b
FC
3226
3227 if (SvTAINTED(dstr))
3228 rxtainted |= SUBST_TAINT_REPL;
f272994b
A
3229 }
3230 else {
6136c704 3231 c = NULL;
f272994b
A
3232 doutf8 = FALSE;
3233 }
3234
71be2cbc 3235 /* can do inplace substitution? */
ed252734 3236 if (c
db2c6cb3 3237#ifdef PERL_ANY_COW
106d9a13 3238 && !was_cow
ed252734 3239#endif
fbfb1899 3240 && (I32)clen <= RX_MINLENRET(rx)
9cefd268
FC
3241 && ( once
3242 || !(r_flags & REXEC_COPY_STR)
3243 || (!SvGMAGICAL(dstr) && !(RX_EXTFLAGS(rx) & RXf_EVAL_SEEN))
3244 )
dbc200c5 3245 && !(RX_EXTFLAGS(rx) & RXf_NO_INPLACE_SUBST)
8ca8a454
NC
3246 && (!doutf8 || SvUTF8(TARG))
3247 && !(rpm->op_pmflags & PMf_NONDESTRUCT))
8b030b38 3248 {
ec911639 3249
db2c6cb3 3250#ifdef PERL_ANY_COW
106d9a13 3251 /* string might have got converted to COW since we set was_cow */
ed252734 3252 if (SvIsCOW(TARG)) {
f7a8268c 3253 if (!force_on_match)
ed252734 3254 goto have_a_cow;
f7a8268c 3255 assert(SvVOK(TARG));
ed252734
NC
3256 }
3257#endif
71be2cbc 3258 if (force_on_match) {
6ac6605d
DM
3259 /* redo the first match, this time with the orig var
3260 * forced into being a string */
71be2cbc 3261 force_on_match = 0;
6ac6605d 3262 orig = SvPV_force_nomg(TARG, len);
71be2cbc
PP
3263 goto force_it;
3264 }
39b40493 3265
71be2cbc 3266 if (once) {
c67ab8f2 3267 char *d, *m;
20be6587
DM
3268 if (RX_MATCH_TAINTED(rx)) /* run time pattern taint, eg locale */
3269 rxtainted |= SUBST_TAINT_PAT;
07bc277f
NC
3270 m = orig + RX_OFFS(rx)[0].start;
3271 d = orig + RX_OFFS(rx)[0].end;
71be2cbc
PP
3272 s = orig;
3273 if (m - s > strend - d) { /* faster to shorten from end */
2ec7214c 3274 I32 i;
71be2cbc
PP
3275 if (clen) {
3276 Copy(c, m, clen, char);
3277 m += clen;
a0d0e21e 3278 }
71be2cbc
PP
3279 i = strend - d;
3280 if (i > 0) {
3281 Move(d, m, i, char);
3282 m += i;
a0d0e21e 3283 }
71be2cbc
PP
3284 *m = '\0';
3285 SvCUR_set(TARG, m - s);
3286 }
2ec7214c
DM
3287 else { /* faster from front */
3288 I32 i = m - s;
71be2cbc 3289 d -= clen;
2ec7214c
DM
3290 if (i > 0)
3291 Move(s, d - i, i, char);
71be2cbc 3292 sv_chop(TARG, d-i);
71be2cbc 3293 if (clen)
c947cd8d 3294 Copy(c, d, clen, char);
71be2cbc 3295 }
8ec5e241 3296 SPAGAIN;
8ca8a454 3297 PUSHs(&PL_sv_yes);
71be2cbc
PP
3298 }
3299 else {
c67ab8f2 3300 char *d, *m;
0395280b 3301 d = s = RX_OFFS(rx)[0].start + orig;
71be2cbc 3302 do {
2b25edcf 3303 I32 i;
5d9574c1 3304 if (UNLIKELY(iters++ > maxiters))
cea2e8a9 3305 DIE(aTHX_ "Substitution loop");
5d9574c1 3306 if (UNLIKELY(RX_MATCH_TAINTED(rx))) /* run time pattern taint, eg locale */
20be6587 3307 rxtainted |= SUBST_TAINT_PAT;
07bc277f 3308 m = RX_OFFS(rx)[0].start + orig;
155aba94 3309 if ((i = m - s)) {
71be2cbc
PP
3310 if (s != d)
3311 Move(s, d, i, char);
3312 d += i;
a0d0e21e 3313 }
71be2cbc
PP
3314 if (clen) {
3315 Copy(c, d, clen, char);
3316 d += clen;
3317 }
07bc277f 3318 s = RX_OFFS(rx)[0].end + orig;
7ce41e5c
FC
3319 } while (CALLREGEXEC(rx, s, strend, orig,
3320 s == m, /* don't match same null twice */
f722798b 3321 TARG, NULL,
d5e7783a 3322 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
71be2cbc 3323 if (s != d) {
2b25edcf 3324 I32 i = strend - s;
aa07b2f6 3325 SvCUR_set(TARG, d - SvPVX_const(TARG) + i);
71be2cbc 3326 Move(s, d, i+1, char); /* include the NUL */
a0d0e21e 3327 }
8ec5e241 3328 SPAGAIN;
3c6ef0a5 3329 mPUSHi(iters);
a0d0e21e
LW
3330 }
3331 }
ff6e92e8 3332 else {
1754320d 3333 bool first;
c67ab8f2 3334 char *m;
1754320d 3335 SV *repl;
a0d0e21e 3336 if (force_on_match) {
6ac6605d
DM
3337 /* redo the first match, this time with the orig var
3338 * forced into being a string */
a0d0e21e 3339 force_on_match = 0;
0c1438a1
NC
3340 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
3341 /* I feel that it should be possible to avoid this mortal copy
3342 given that the code below copies into a new destination.
3343 However, I suspect it isn't worth the complexity of
3344 unravelling the C<goto force_it> for the small number of
3345 cases where it would be viable to drop into the copy code. */
3346 TARG = sv_2mortal(newSVsv(TARG));
3347 }
6ac6605d 3348 orig = SvPV_force_nomg(TARG, len);
a0d0e21e
LW
3349 goto force_it;
3350 }
db2c6cb3 3351#ifdef PERL_ANY_COW
ed252734
NC
3352 have_a_cow:
3353#endif
20be6587
DM
3354 if (RX_MATCH_TAINTED(rx)) /* run time pattern taint, eg locale */
3355 rxtainted |= SUBST_TAINT_PAT;
1754320d 3356 repl = dstr;
0395280b
DM
3357 s = RX_OFFS(rx)[0].start + orig;
3358 dstr = newSVpvn_flags(orig, s-orig,
3359 SVs_TEMP | (DO_UTF8(TARG) ? SVf_UTF8 : 0));
a0d0e21e 3360 if (!c) {
eb578fdb 3361 PERL_CONTEXT *cx;
8ec5e241 3362 SPAGAIN;
0395280b 3363 m = orig;
20be6587
DM
3364 /* note that a whole bunch of local vars are saved here for
3365 * use by pp_substcont: here's a list of them in case you're
3366 * searching for places in this sub that uses a particular var:
3367 * iters maxiters r_flags oldsave rxtainted orig dstr targ
3368 * s m strend rx once */
490576d1 3369 CX_PUSHSUBST(cx);
20e98b0f 3370 RETURNOP(cPMOP->op_pmreplrootu.op_pmreplroot);
a0d0e21e 3371 }
1754320d 3372 first = TRUE;
a0d0e21e 3373 do {
5d9574c1 3374 if (UNLIKELY(iters++ > maxiters))
cea2e8a9 3375 DIE(aTHX_ "Substitution loop");
5d9574c1 3376 if (UNLIKELY(RX_MATCH_TAINTED(rx)))
20be6587 3377 rxtainted |= SUBST_TAINT_PAT;
07bc277f 3378 if (RX_MATCH_COPIED(rx) && RX_SUBBEG(rx) != orig) {
c67ab8f2
DM
3379 char *old_s = s;
3380 char *old_orig = orig;
6502e081 3381 assert(RX_SUBOFFSET(rx) == 0);
c67ab8f2 3382
07bc277f 3383 orig = RX_SUBBEG(rx);
c67ab8f2
DM
3384 s = orig + (old_s - old_orig);
3385 strend = s + (strend - old_s);
a0d0e21e 3386 }
07bc277f 3387 m = RX_OFFS(rx)[0].start + orig;
64534138 3388 sv_catpvn_nomg_maybeutf8(dstr, s, m - s, DO_UTF8(TARG));
07bc277f 3389 s = RX_OFFS(rx)[0].end + orig;
1754320d
FC
3390 if (first) {
3391 /* replacement already stringified */
3392 if (clen)
64534138 3393 sv_catpvn_nomg_maybeutf8(dstr, c, clen, doutf8);
1754320d
FC
3394 first = FALSE;
3395 }
3396 else {
8df0e7a2 3397 sv_catsv(dstr, repl);
5d9574c1 3398 if (UNLIKELY(SvTAINTED(repl)))
bb933b9b 3399 rxtainted |= SUBST_TAINT_REPL;
1754320d 3400 }
a0d0e21e
LW
3401 if (once)
3402 break;
ff27773b
KW
3403 } while (CALLREGEXEC(rx, s, strend, orig,
3404 s == m, /* Yields minend of 0 or 1 */
d5e7783a
DM
3405 TARG, NULL,
3406 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
aba224f7 3407 assert(strend >= s);
64534138 3408 sv_catpvn_nomg_maybeutf8(dstr, s, strend - s, DO_UTF8(TARG));
748a9306 3409
8ca8a454
NC
3410 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
3411 /* From here on down we're using the copy, and leaving the original
3412 untouched. */
3413 TARG = dstr;
3414 SPAGAIN;
3415 PUSHs(dstr);
3416 } else {
db2c6cb3 3417#ifdef PERL_ANY_COW
8ca8a454
NC
3418 /* The match may make the string COW. If so, brilliant, because
3419 that's just saved us one malloc, copy and free - the regexp has
3420 donated the old buffer, and we malloc an entirely new one, rather
3421 than the regexp malloc()ing a buffer and copying our original,
3422 only for us to throw it away here during the substitution. */
3423 if (SvIsCOW(TARG)) {
3424 sv_force_normal_flags(TARG, SV_COW_DROP_PV);
3425 } else
ed252734 3426#endif
8ca8a454
NC
3427 {
3428 SvPV_free(TARG);
3429 }
3430 SvPV_set(TARG, SvPVX(dstr));
3431 SvCUR_set(TARG, SvCUR(dstr));
3432 SvLEN_set(TARG, SvLEN(dstr));
64534138 3433 SvFLAGS(TARG) |= SvUTF8(dstr);
8ca8a454 3434 SvPV_set(dstr, NULL);
748a9306 3435
8ca8a454 3436 SPAGAIN;
3c6ef0a5 3437 mPUSHi(iters);
8ca8a454
NC
3438 }
3439 }
3440
3441 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
3442 (void)SvPOK_only_UTF8(TARG);
a0d0e21e 3443 }
20be6587 3444
ef07e810 3445 /* See "how taint works" above */
284167a5 3446 if (TAINTING_get) {
20be6587
DM
3447 if ((rxtainted & SUBST_TAINT_PAT) ||
3448 ((rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_RETAINT)) ==
3449 (SUBST_TAINT_STR|SUBST_TAINT_RETAINT))
3450 )
3451 (RX_MATCH_TAINTED_on(rx)); /* taint $1 et al */
3452
3453 if (!(rxtainted & SUBST_TAINT_BOOLRET)
3454 && (rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT))
3455 )
3456 SvTAINTED_on(TOPs); /* taint return value */
3457 else
3458 SvTAINTED_off(TOPs); /* may have got tainted earlier */
3459
3460 /* needed for mg_set below */
284167a5
SM
3461 TAINT_set(
3462 cBOOL(rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT|SUBST_TAINT_REPL))
3463 );
20be6587
DM
3464 SvTAINT(TARG);
3465 }
3466 SvSETMAGIC(TARG); /* PL_tainted must be correctly set for this mg_set */
3467 TAINT_NOT;
f1a76097
DM
3468 LEAVE_SCOPE(oldsave);
3469 RETURN;
a0d0e21e
LW
3470}
3471
3472PP(pp_grepwhile)
3473{
20b7effb 3474 dSP;
a0d0e21e
LW
3475
3476 if (SvTRUEx(POPs))
3280af22
NIS
3477 PL_stack_base[PL_markstack_ptr[-1]++] = PL_stack_base[*PL_markstack_ptr];
3478 ++*PL_markstack_ptr;
b2a2a901 3479 FREETMPS;
d343c3ef 3480 LEAVE_with_name("grep_item"); /* exit inner scope */
a0d0e21e
LW
3481
3482 /* All done yet? */
5d9574c1 3483 if (UNLIKELY(PL_stack_base + *PL_markstack_ptr > SP)) {
a0d0e21e 3484 I32 items;
1c23e2bd 3485 const U8 gimme = GIMME_V;
a0d0e21e 3486
d343c3ef 3487 LEAVE_with_name("grep"); /* exit outer scope */
a0d0e21e 3488 (void)POPMARK; /* pop src */
3280af22 3489 items = --*PL_markstack_ptr - PL_markstack_ptr[-1];
a0d0e21e 3490 (void)POPMARK; /* pop dst */
3280af22 3491 SP = PL_stack_base + POPMARK; /* pop original mark */
54310121 3492 if (gimme == G_SCALAR) {
7cc47870
RGS
3493 dTARGET;
3494 XPUSHi(items);
a0d0e21e 3495 }
54310121
PP
3496 else if (gimme == G_ARRAY)
3497 SP += items;
a0d0e21e
LW
3498 RETURN;
3499 }
3500 else {
3501 SV *src;
3502
d343c3ef 3503 ENTER_with_name("grep_item"); /* enter inner scope */
1d7c1841 3504 SAVEVPTR(PL_curpm);
a0d0e21e 3505
6cae08a8 3506 src = PL_stack_base[TOPMARK];
60779a30 3507 if (SvPADTMP(src)) {
6cae08a8 3508 src = PL_stack_base[TOPMARK] = sv_mortalcopy(src);
a0ed822e
FC
3509 PL_tmps_floor++;
3510 }
a0d0e21e 3511 SvTEMP_off(src);
ffd49c98 3512 DEFSV_set(src);
a0d0e21e
LW
3513
3514 RETURNOP(cLOGOP->op_other);
3515 }
3516}
3517
799da9d7 3518/* leave_adjust_stacks():
f7a874b8 3519 *
e02ce34b
DM
3520 * Process a scope's return args (in the range from_sp+1 .. PL_stack_sp),
3521 * positioning them at to_sp+1 onwards, and do the equivalent of a
3522 * FREEMPS and TAINT_NOT.
3523 *
f7a874b8
DM
3524 * Not intended to be called in void context.
3525 *
799da9d7
DM
3526 * When leaving a sub, eval, do{} or other scope, the things that need
3527 * doing to process the return args are:
f7a874b8 3528 * * in scalar context, only return the last arg (or PL_sv_undef if none);
799da9d7
DM
3529 * * for the types of return that return copies of their args (such
3530 * as rvalue sub return), make a mortal copy of every return arg,
3531 * except where we can optimise the copy away without it being
3532 * semantically visible;
3533 * * make sure that the arg isn't prematurely freed; in the case of an
3534 * arg not copied, this may involve mortalising it. For example, in
f7a874b8
DM
3535 * C<sub f { my $x = ...; $x }>, $x would be freed when we do
3536 * CX_LEAVE_SCOPE(cx) unless it's protected or copied.
3537 *
799da9d7
DM
3538 * What condition to use when deciding whether to pass the arg through
3539 * or make a copy, is determined by the 'pass' arg; its valid values are:
3540 * 0: rvalue sub/eval exit
3541 * 1: other rvalue scope exit
3542 * 2: :lvalue sub exit in rvalue context
3543 * 3: :lvalue sub exit in lvalue context and other lvalue scope exits
3544 *
f7a874b8 3545 * There is a big issue with doing a FREETMPS. We would like to free any
799da9d7 3546 * temps created by the last statement which the sub executed, rather than
f7a874b8
DM
3547 * leaving them for the caller. In a situation where a sub call isn't
3548 * soon followed by a nextstate (e.g. nested recursive calls, a la
3549 * fibonacci()), temps can accumulate, causing memory and performance
3550 * issues.
3551 *
3552 * On the other hand, we don't want to free any TEMPs which are keeping
799da9d7
DM
3553 * alive any return args that we skipped copying; nor do we wish to undo
3554 * any mortalising done here.
f7a874b8
DM
3555 *
3556 * The solution is to split the temps stack frame into two, with a cut
3557 * point delineating the two halves. We arrange that by the end of this
3558 * function, all the temps stack frame entries we wish to keep are in the
799da9d7 3559 * range PL_tmps_floor+1.. tmps_base-1, while the ones to free now are in
f7a874b8
DM
3560 * the range tmps_base .. PL_tmps_ix. During the course of this
3561 * function, tmps_base starts off as PL_tmps_floor+1, then increases
3562 * whenever we find or create a temp that we know should be kept. In
3563 * general the stuff above tmps_base is undecided until we reach the end,
3564 * and we may need a sort stage for that.
3565 *
3566 * To determine whether a TEMP is keeping a return arg alive, every
3567 * arg that is kept rather than copied and which has the SvTEMP flag
3568 * set, has the flag temporarily unset, to mark it. At the end we scan
799da9d7 3569 * the temps stack frame above the cut for entries without SvTEMP and
f7a874b8 3570 * keep them, while turning SvTEMP on again. Note that if we die before
799da9d7 3571 * the SvTEMPs flags are set again, its safe: at worst, subsequent use of
f7a874b8
DM
3572 * those SVs may be slightly less efficient.
3573 *
3574 * In practice various optimisations for some common cases mean we can
3575 * avoid most of the scanning and swapping about with the temps stack.
3576 */
3577
799da9d7 3578void
1c23e2bd 3579Perl_leave_adjust_stacks(pTHX_ SV **from_sp, SV **to_sp, U8 gimme, int pass)
a0d0e21e 3580{
263e0548 3581 dVAR;
20b7effb 3582 dSP;
f7a874b8
DM
3583 SSize_t tmps_base; /* lowest index into tmps stack that needs freeing now */
3584 SSize_t nargs;
3585
799da9d7
DM
3586 PERL_ARGS_ASSERT_LEAVE_ADJUST_STACKS;
3587
f7a874b8
DM
3588 TAINT_NOT;
3589
3590 if (gimme == G_ARRAY) {
e02ce34b
DM
3591 nargs = SP - from_sp;
3592 from_sp++;
f7a874b8
DM
3593 }
3594 else {
3595 assert(gimme == G_SCALAR);
e02ce34b 3596 if (UNLIKELY(from_sp >= SP)) {
f7a874b8 3597 /* no return args */
e02ce34b 3598 assert(from_sp == SP);
f7a874b8
DM
3599 EXTEND(SP, 1);
3600 *++SP = &PL_sv_undef;
e02ce34b 3601 to_sp = SP;
f7a874b8
DM
3602 nargs = 0;
3603 }
3604 else {
3605 from_sp = SP;
3606 nargs = 1;
3607 }
3608 }
3609
3610 /* common code for G_SCALAR and G_ARRAY */
3611
3612 tmps_base = PL_tmps_floor + 1;
3613
3614 assert(nargs >= 0);
3615 if (nargs) {
3616 /* pointer version of tmps_base. Not safe across temp stack
3617 * reallocs. */
3618 SV **tmps_basep;
3619
3620 EXTEND_MORTAL(nargs); /* one big extend for worst-case scenario */
3621 tmps_basep = PL_tmps_stack + tmps_base;
f7a874b8
DM
3622
3623 /* process each return arg */
3624
3625 do {
3626 SV *sv = *from_sp++;
3627
3628 assert(PL_tmps_ix + nargs < PL_tmps_max);
3645bb38
DM
3629#ifdef DEBUGGING
3630 /* PADTMPs with container set magic shouldn't appear in the
3631 * wild. This assert is more important for pp_leavesublv(),
3632 * but by testing for it here, we're more likely to catch
3633 * bad cases (what with :lvalue subs not being widely
3634 * deployed). The two issues are that for something like
3635 * sub :lvalue { $tied{foo} }
3636 * or
3637 * sub :lvalue { substr($foo,1,2) }
3638 * pp_leavesublv() will croak if the sub returns a PADTMP,