This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
Better optimise array and hash assignment
[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
a0d0e21e
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"]
a0d0e21e
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
a0d0e21e
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 }
1166 else if (!(do_rc1 && SvREFCNT(svl) == 1) && svl != &PL_sv_undef) {
1167 assert(!SvIMMORTAL(svl));
1168 SvFLAGS(svl) |= SVf_BREAK;
1169 marked = TRUE;
1170 }
1171 else if (!marked) {
1172 /* don't check RH element if no SVf_BREAK flags set yet */
1173 if (!lcount)
1174 break;
1175 continue;
1176 }
1177 }
1178
1179 /* see if corresponding RH element needs copying */
1180
1181 assert(marked);
1182 svr = *relem;
1183 assert(svr);
1184
5c1db569 1185 if (UNLIKELY(SvFLAGS(svr) & (SVf_BREAK|SVs_GMG) || copy_all)) {
a5f48505 1186
ebc643ce
DM
1187#ifdef DEBUGGING
1188 if (fake) {
9ae0115f 1189 /* op_dump(PL_op); */
ebc643ce
DM
1190 Perl_croak(aTHX_
1191 "panic: aassign skipped needed copy of common RH elem %"
1192 UVuf, (UV)(relem - firstrelem));
1193 }
1194#endif
1195
a5f48505
DM
1196 TAINT_NOT; /* Each item is independent */
1197
1198 /* Dear TODO test in t/op/sort.t, I love you.
1199 (It's relying on a panic, not a "semi-panic" from newSVsv()
1200 and then an assertion failure below.) */
1201 if (UNLIKELY(SvIS_FREED(svr))) {
1202 Perl_croak(aTHX_ "panic: attempt to copy freed scalar %p",
1203 (void*)svr);
1204 }
1205 /* avoid break flag while copying; otherwise COW etc
1206 * disabled... */
1207 SvFLAGS(svr) &= ~SVf_BREAK;
1208 /* Not newSVsv(), as it does not allow copy-on-write,
8c1e192f
DM
1209 resulting in wasteful copies.
1210 Also, we use SV_NOSTEAL in case the SV is used more than
1211 once, e.g. (...) = (f())[0,0]
1212 Where the same SV appears twice on the RHS without a ref
1213 count bump. (Although I suspect that the SV won't be
1214 stealable here anyway - DAPM).
1215 */
a5f48505
DM
1216 *relem = sv_mortalcopy_flags(svr,
1217 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
1218 /* ... but restore afterwards in case it's needed again,
1219 * e.g. ($a,$b,$c) = (1,$a,$a)
1220 */
1221 SvFLAGS(svr) |= SVf_BREAK;
1222 }
1223
1224 if (!lcount)
1225 break;
1226 }
1227
1228 if (!marked)
1229 return;
1230
1231 /*unmark LHS */
1232
1233 while (lelem > firstlelem) {
1234 SV * const svl = *(--lelem);
1235 if (svl)
1236 SvFLAGS(svl) &= ~SVf_BREAK;
1237 }
1238}
1239
1240
1241
a0d0e21e
LW
1242PP(pp_aassign)
1243{
27da23d5 1244 dVAR; dSP;
3280af22
NIS
1245 SV **lastlelem = PL_stack_sp;
1246 SV **lastrelem = PL_stack_base + POPMARK;
1247 SV **firstrelem = PL_stack_base + POPMARK + 1;
a0d0e21e
LW
1248 SV **firstlelem = lastrelem + 1;
1249
eb578fdb
KW
1250 SV **relem;
1251 SV **lelem;
a0d0e21e 1252
eb578fdb 1253 AV *ary;
a0d0e21e 1254
1c23e2bd 1255 U8 gimme;
a0d0e21e 1256 HV *hash;
a68090fe
DM
1257 /* PL_delaymagic is restored by JUMPENV_POP on dieing, so we
1258 * only need to save locally, not on the save stack */
1259 U16 old_delaymagic = PL_delaymagic;
ebc643ce
DM
1260#ifdef DEBUGGING
1261 bool fake = 0;
1262#endif
5637b936 1263
3280af22 1264 PL_delaymagic = DM_DELAY; /* catch simultaneous items */
a0d0e21e
LW
1265
1266 /* If there's a common identifier on both sides we have to take
1267 * special care that assigning the identifier on the left doesn't
1268 * clobber a value on the right that's used later in the list.
1269 */
acdea6f0 1270
beb08a1e
TC
1271 /* at least 2 LH and RH elements, or commonality isn't an issue */
1272 if (firstlelem < lastlelem && firstrelem < lastrelem) {
5c1db569
TC
1273 for (relem = firstrelem+1; relem <= lastrelem; relem++) {
1274 if (SvGMAGICAL(*relem))
1275 goto do_scan;
1276 }
beb08a1e
TC
1277 for (lelem = firstlelem; lelem <= lastlelem; lelem++) {
1278 if (*lelem && SvSMAGICAL(*lelem))
1279 goto do_scan;
a5f48505 1280 }
beb08a1e
TC
1281 if ( PL_op->op_private & (OPpASSIGN_COMMON_SCALAR|OPpASSIGN_COMMON_RC1) ) {
1282 if (PL_op->op_private & OPpASSIGN_COMMON_RC1) {
1283 /* skip the scan if all scalars have a ref count of 1 */
1284 for (lelem = firstlelem; lelem <= lastlelem; lelem++) {
8b0c3377 1285 SV *sv = *lelem;
beb08a1e
TC
1286 if (!sv || SvREFCNT(sv) == 1)
1287 continue;
1288 if (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVAV)
1289 goto do_scan;
1290 break;
1291 }
1292 }
1293 else {
1294 do_scan:
1295 S_aassign_copy_common(aTHX_
1296 firstlelem, lastlelem, firstrelem, lastrelem
ebc643ce 1297#ifdef DEBUGGING
beb08a1e 1298 , fake
ebc643ce 1299#endif
beb08a1e
TC
1300 );
1301 }
a5f48505 1302 }
a0d0e21e 1303 }
ebc643ce
DM
1304#ifdef DEBUGGING
1305 else {
1306 /* on debugging builds, do the scan even if we've concluded we
1307 * don't need to, then panic if we find commonality. Note that the
1308 * scanner assumes at least 2 elements */
1309 if (firstlelem < lastlelem && firstrelem < lastrelem) {
1310 fake = 1;
1311 goto do_scan;
1312 }
1313 }
1314#endif
a0d0e21e 1315
a5f48505 1316 gimme = GIMME_V;
a0d0e21e
LW
1317 relem = firstrelem;
1318 lelem = firstlelem;
4608196e
RGS
1319 ary = NULL;
1320 hash = NULL;
10c8fecd 1321
8b0c3377
DM
1322 if (relem > lastrelem)
1323 goto no_relems;
1324
1325 /* first lelem loop while there are still relems */
5d9574c1 1326 while (LIKELY(lelem <= lastlelem)) {
bdaf10a5 1327 bool alias = FALSE;
8b0c3377
DM
1328 SV *lsv = *lelem++;
1329
1330 assert(relem <= lastrelem);
1331 if (UNLIKELY(!lsv)) {
bdaf10a5 1332 alias = TRUE;
8b0c3377
DM
1333 lsv = *lelem++;
1334 ASSUME(SvTYPE(lsv) == SVt_PVAV);
bdaf10a5 1335 }
a5f48505 1336
8b0c3377
DM
1337 switch (SvTYPE(lsv)) {
1338 case SVt_PVAV: {
1339 SV **svp;
1340 SSize_t i;
1341 SSize_t tmps_base;
1342 SSize_t nelems = lastrelem - relem + 1;
1343
1344 ary = MUTABLE_AV(lsv);
1345
1346 /* Assigning to an aggregate is tricky. First there is the
1347 * issue of commonality, e.g. @a = ($a[0]). Since the
1348 * stack isn't refcounted, clearing @a prior to storing
1349 * elements will free $a[0]. Similarly with
1350 * sub FETCH { $status[$_[1]] } @status = @tied[0,1];
1351 *
1352 * The way to avoid these issues is to make the copy of each
1353 * SV (and we normally store a *copy* in the array) *before*
1354 * clearing the array. But this has a problem in that
1355 * if the code croaks during copying, the not-yet-stored copies
1356 * could leak. One way to avoid this is to make all the copies
1357 * mortal, but that's quite expensive.
1358 *
1359 * The current solution to these issues is to use a chunk
1360 * of the tmps stack as a temporary refcounted-stack. SVs
1361 * will be put on there during processing to avoid leaks,
1362 * but will be removed again before the end of this block,
1363 * so free_tmps() is never normally called. Also, the
1364 * sv_refcnt of the SVs doesn't have to be manipulated, since
1365 * the ownership of 1 reference count is transferred directly
1366 * from the tmps stack to the AV when the SV is stored.
1367 *
1368 * We disarm slots in the temps stack by storing PL_sv_undef
1369 * there: it doesn't matter if that SV's refcount is
1370 * repeatedly decremented during a croak. But usually this is
1371 * only an interim measure. By the end of this code block
1372 * we try where possible to not leave any PL_sv_undef's on the
1373 * tmps stack e.g. by shuffling newer entries down.
1374 *
1375 * There is one case where we don't copy: non-magical
1376 * SvTEMP(sv)'s with a ref count of 1. The only owner of these
1377 * is on the tmps stack, so its safe to directly steal the SV
1378 * rather than copying. This is common in things like function
1379 * returns, map etc, which all return a list of such SVs.
1380 *
1381 * Note however something like @a = (f())[0,0], where there is
1382 * a danger of the same SV being shared: this avoided because
1383 * when the SV is stored as $a[0], its ref count gets bumped,
1384 * so the RC==1 test fails and the second element is copied
1385 * instead.
1386 *
1387 * We also use one slot in the tmps stack to hold an extra
1388 * ref to the array, to ensure it doesn't get prematurely
1389 * freed. Again, this is removed before the end of this block.
1390 *
1391 * Note that OPpASSIGN_COMMON_AGG is used to flag a possible
1392 * @a = ($a[0]) case, but the current implementation uses the
1393 * same algorithm regardless, so ignores that flag. (It *is*
1394 * used in the hash branch below, however).
1395 */
1396
1397 /* Reserve slots for ary, plus the elems we're about to copy,
1398 * then protect ary and temporarily void the remaining slots
1399 * with &PL_sv_undef */
1400 EXTEND_MORTAL(nelems + 1);
1401 PL_tmps_stack[++PL_tmps_ix] = SvREFCNT_inc_simple_NN(ary);
1402 tmps_base = PL_tmps_ix + 1;
1403 for (i = 0; i < nelems; i++)
1404 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
1405 PL_tmps_ix += nelems;
1406
1407 /* Make a copy of each RHS elem and save on the tmps_stack
1408 * (or pass through where we can optimise away the copy) */
1409
1410 if (UNLIKELY(alias)) {
1411 U32 lval = (gimme == G_ARRAY)
1412 ? (PL_op->op_flags & OPf_MOD || LVRET) : 0;
a5f48505 1413 for (svp = relem; svp <= lastrelem; svp++) {
8b0c3377
DM
1414 SV *rsv = *svp;
1415
1416 SvGETMAGIC(rsv);
1417 if (!SvROK(rsv))
1418 DIE(aTHX_ "Assigned value is not a reference");
1419 if (SvTYPE(SvRV(rsv)) > SVt_PVLV)
1420 /* diag_listed_as: Assigned value is not %s reference */
1421 DIE(aTHX_
1422 "Assigned value is not a SCALAR reference");
1423 if (lval)
1424 *svp = rsv = sv_mortalcopy(rsv);
1425 /* XXX else check for weak refs? */
1426 rsv = SvREFCNT_inc_NN(SvRV(rsv));
1427 assert(tmps_base <= PL_tmps_max);
1428 PL_tmps_stack[tmps_base++] = rsv;
a5f48505 1429 }
a5f48505 1430 }
8b0c3377
DM
1431 else {
1432 for (svp = relem; svp <= lastrelem; svp++) {
1433 SV *rsv = *svp;
a5f48505 1434
8b0c3377
DM
1435 if (SvTEMP(rsv) && !SvGMAGICAL(rsv) && SvREFCNT(rsv) == 1) {
1436 /* can skip the copy */
1437 SvREFCNT_inc_simple_void_NN(rsv);
1438 SvTEMP_off(rsv);
1439 }
a5f48505 1440 else {
8b0c3377
DM
1441 SV *nsv;
1442 /* do get before newSV, in case it dies and leaks */
1443 SvGETMAGIC(rsv);
1444 nsv = newSV(0);
8c1e192f
DM
1445 /* see comment in S_aassign_copy_common about
1446 * SV_NOSTEAL */
8b0c3377
DM
1447 sv_setsv_flags(nsv, rsv,
1448 (SV_DO_COW_SVSETSV|SV_NOSTEAL));
1449 rsv = *svp = nsv;
a5f48505 1450 }
8b0c3377
DM
1451
1452 assert(tmps_base <= PL_tmps_max);
1453 PL_tmps_stack[tmps_base++] = rsv;
1454 }
1455 }
1456
1457 if (SvRMAGICAL(ary) || AvFILLp(ary) >= 0) /* may be non-empty */
1458 av_clear(ary);
1459
1460 /* store in the array, the SVs that are in the tmps stack */
1461
1462 tmps_base -= nelems;
1463
1464 if (SvRMAGICAL(ary) || SvREADONLY(ary) || !AvREAL(ary)) {
1465 /* for arrays we can't cheat with, use the official API */
1466 av_extend(ary, nelems - 1);
1467 for (i = 0; i < nelems; i++) {
1468 SV **svp = &(PL_tmps_stack[tmps_base + i]);
1469 SV *rsv = *svp;
1470 /* A tied store won't take ownership of rsv, so keep
1471 * the 1 refcnt on the tmps stack; otherwise disarm
1472 * the tmps stack entry */
1473 if (av_store(ary, i, rsv))
1474 *svp = &PL_sv_undef;
1475 /* av_store() may have added set magic to rsv */;
1476 SvSETMAGIC(rsv);
1477 }
1478 /* disarm ary refcount: see comments below about leak */
1479 PL_tmps_stack[tmps_base - 1] = &PL_sv_undef;
1480 }
1481 else {
1482 /* directly access/set the guts of the AV */
1483 SSize_t fill = nelems - 1;
1484 if (fill > AvMAX(ary))
1485 av_extend_guts(ary, fill, &AvMAX(ary), &AvALLOC(ary),
1486 &AvARRAY(ary));
1487 AvFILLp(ary) = fill;
1488 Copy(&(PL_tmps_stack[tmps_base]), AvARRAY(ary), nelems, SV*);
1489 /* Quietly remove all the SVs from the tmps stack slots,
1490 * since ary has now taken ownership of the refcnt.
1491 * Also remove ary: which will now leak if we die before
1492 * the SvREFCNT_dec_NN(ary) below */
1493 if (UNLIKELY(PL_tmps_ix >= tmps_base + nelems))
1494 Move(&PL_tmps_stack[tmps_base + nelems],
1495 &PL_tmps_stack[tmps_base - 1],
1496 PL_tmps_ix - (tmps_base + nelems) + 1,
1497 SV*);
1498 PL_tmps_ix -= (nelems + 1);
1499 }
1500
5d9574c1 1501 if (UNLIKELY(PL_delaymagic & DM_ARRAY_ISA))
8b0c3377 1502 /* its assumed @ISA set magic can't die and leak ary */
ad64d0ec 1503 SvSETMAGIC(MUTABLE_SV(ary));
8b0c3377
DM
1504 SvREFCNT_dec_NN(ary);
1505
1506 relem = lastrelem + 1;
1507 goto no_relems;
a5f48505
DM
1508 }
1509
10c8fecd 1510 case SVt_PVHV: { /* normal hash */
8b0c3377
DM
1511
1512 SV **svp;
1513 bool dirty_tmps;
1514 SSize_t i;
1515 SSize_t tmps_base;
1516 SSize_t nelems = lastrelem - relem + 1;
1517
1518 hash = MUTABLE_HV(lsv);
1519
1520 if (UNLIKELY(nelems & 1)) {
1521 do_oddball(lastrelem, relem);
1522 /* we have firstlelem to reuse, it's not needed any more */
1523 *++lastrelem = &PL_sv_undef;
1524 nelems++;
1525 }
1526
1527 /* See the SVt_PVAV branch above for a long description of
1528 * how the following all works. The main difference for hashes
1529 * is that we treat keys and values separately (and have
1530 * separate loops for them): as for arrays, values are always
1531 * copied (except for the SvTEMP optimisation), since they
1532 * need to be stored in the hash; while keys are only
1533 * processed where they might get prematurely freed or
1534 * whatever. */
1535
1536 /* tmps stack slots:
1537 * * reserve a slot for the hash keepalive;
1538 * * reserve slots for the hash values we're about to copy;
1539 * * preallocate for the keys we'll possibly copy or refcount bump
1540 * later;
1541 * then protect hash and temporarily void the remaining
1542 * value slots with &PL_sv_undef */
1543 EXTEND_MORTAL(nelems + 1);
1544
1545 /* convert to number of key/value pairs */
1546 nelems >>= 1;
1547
1548 PL_tmps_stack[++PL_tmps_ix] = SvREFCNT_inc_simple_NN(hash);
1549 tmps_base = PL_tmps_ix + 1;
1550 for (i = 0; i < nelems; i++)
1551 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
1552 PL_tmps_ix += nelems;
1553
1554 /* Make a copy of each RHS hash value and save on the tmps_stack
1555 * (or pass through where we can optimise away the copy) */
1556
1557 for (svp = relem + 1; svp <= lastrelem; svp += 2) {
1558 SV *rsv = *svp;
1559
1560 if (SvTEMP(rsv) && !SvGMAGICAL(rsv) && SvREFCNT(rsv) == 1) {
1561 /* can skip the copy */
1562 SvREFCNT_inc_simple_void_NN(rsv);
1563 SvTEMP_off(rsv);
1564 }
1565 else {
1566 SV *nsv;
1567 /* do get before newSV, in case it dies and leaks */
1568 SvGETMAGIC(rsv);
1569 nsv = newSV(0);
1570 /* see comment in S_aassign_copy_common about
1571 * SV_NOSTEAL */
1572 sv_setsv_flags(nsv, rsv,
1573 (SV_DO_COW_SVSETSV|SV_NOSTEAL));
1574 rsv = *svp = nsv;
1c4ea384
RZ
1575 }
1576
8b0c3377
DM
1577 assert(tmps_base <= PL_tmps_max);
1578 PL_tmps_stack[tmps_base++] = rsv;
1579 }
1580 tmps_base -= nelems;
a5f48505 1581
a5f48505 1582
8b0c3377
DM
1583 /* possibly protect keys */
1584
1585 if (UNLIKELY(gimme == G_ARRAY)) {
1586 /* handle e.g.
1587 * @a = ((%h = ($$r, 1)), $r = "x");
1588 * $_++ for %h = (1,2,3,4);
1589 */
1590 EXTEND_MORTAL(nelems);
1591 for (svp = relem; svp <= lastrelem; svp += 2)
1592 *svp = sv_mortalcopy_flags(*svp,
1593 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
1594 }
1595 else if (PL_op->op_private & OPpASSIGN_COMMON_AGG) {
1596 /* for possible commonality, e.g.
1597 * %h = ($h{a},1)
1598 * avoid premature freeing RHS keys by mortalising
1599 * them.
1600 * For a magic element, make a copy so that its magic is
1601 * called *before* the hash is emptied (which may affect
1602 * a tied value for example).
1603 * In theory we should check for magic keys in all
1604 * cases, not just under OPpASSIGN_COMMON_AGG, but in
1605 * practice, !OPpASSIGN_COMMON_AGG implies only
1606 * constants or padtmps on the RHS.
1607 */
1608 EXTEND_MORTAL(nelems);
1609 for (svp = relem; svp <= lastrelem; svp += 2) {
1610 SV *rsv = *svp;
1611 if (UNLIKELY(SvGMAGICAL(rsv))) {
1612 SSize_t n;
a5f48505
DM
1613 *svp = sv_mortalcopy_flags(*svp,
1614 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
8b0c3377
DM
1615 /* allow other branch to continue pushing
1616 * onto tmps stack without checking each time */
1617 n = (lastrelem - relem) >> 1;
1618 EXTEND_MORTAL(n);
a5f48505 1619 }
8b0c3377
DM
1620 else
1621 PL_tmps_stack[++PL_tmps_ix] =
1622 SvREFCNT_inc_simple_NN(rsv);
a5f48505 1623 }
8b0c3377 1624 }
a5f48505 1625
8b0c3377
DM
1626 if (SvRMAGICAL(hash) || HvUSEDKEYS(hash))
1627 hv_clear(hash);
a5f48505 1628
8b0c3377
DM
1629 /* now assign the keys and values to the hash */
1630
1631 dirty_tmps = FALSE;
1632
1633 if (UNLIKELY(gimme == G_ARRAY)) {
1634 /* @a = (%h = (...)) etc */
1635 SV **svp;
1636 SV **topelem = relem;
1637
1638 for (i = 0, svp = relem; svp <= lastrelem; i++, svp++) {
1639 SV *key = *svp++;
1640 SV *val = *svp;
1641 /* remove duplicates from list we return */
1642 if (!hv_exists_ent(hash, key, 0)) {
1643 /* copy key back: possibly to an earlier
1644 * stack location if we encountered dups earlier,
1645 * The values will be updated later
1646 */
1647 *topelem = key;
1648 topelem += 2;
632b9d6f 1649 }
8b0c3377
DM
1650 /* A tied store won't take ownership of val, so keep
1651 * the 1 refcnt on the tmps stack; otherwise disarm
1652 * the tmps stack entry */
1653 if (hv_store_ent(hash, key, val, 0))
1654 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
1655 else
1656 dirty_tmps = TRUE;
1657 /* hv_store_ent() may have added set magic to val */;
1658 SvSETMAGIC(val);
1659 }
1660 if (topelem < svp) {
1c4ea384
RZ
1661 /* at this point we have removed the duplicate key/value
1662 * pairs from the stack, but the remaining values may be
1663 * wrong; i.e. with (a 1 a 2 b 3) on the stack we've removed
1664 * the (a 2), but the stack now probably contains
1665 * (a <freed> b 3), because { hv_save(a,1); hv_save(a,2) }
1666 * obliterates the earlier key. So refresh all values. */
8b0c3377
DM
1667 lastrelem = topelem - 1;
1668 while (relem < lastrelem) {
1c4ea384
RZ
1669 HE *he;
1670 he = hv_fetch_ent(hash, *relem++, 0, 0);
1671 *relem++ = (he ? HeVAL(he) : &PL_sv_undef);
1672 }
1673 }
8b0c3377
DM
1674 }
1675 else {
1676 SV **svp;
1677 for (i = 0, svp = relem; svp <= lastrelem; i++, svp++) {
1678 SV *key = *svp++;
1679 SV *val = *svp;
1680 if (hv_store_ent(hash, key, val, 0))
1681 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
1682 else
1683 dirty_tmps = TRUE;
1684 /* hv_store_ent() may have added set magic to val */;
1685 SvSETMAGIC(val);
1686 }
1687 }
1688
1689 if (dirty_tmps) {
1690 /* there are still some 'live' recounts on the tmps stack
1691 * - usually caused by storing into a tied hash. So let
1692 * free_tmps() do the proper but slow job later.
1693 * Just disarm hash refcount: see comments below about leak
1694 */
1695 PL_tmps_stack[tmps_base - 1] = &PL_sv_undef;
1696 }
1697 else {
1698 /* Quietly remove all the SVs from the tmps stack slots,
1699 * since hash has now taken ownership of the refcnt.
1700 * Also remove hash: which will now leak if we die before
1701 * the SvREFCNT_dec_NN(hash) below */
1702 if (UNLIKELY(PL_tmps_ix >= tmps_base + nelems))
1703 Move(&PL_tmps_stack[tmps_base + nelems],
1704 &PL_tmps_stack[tmps_base - 1],
1705 PL_tmps_ix - (tmps_base + nelems) + 1,
1706 SV*);
1707 PL_tmps_ix -= (nelems + 1);
1708 }
1709
1710 SvREFCNT_dec_NN(hash);
1711
1712 relem = lastrelem + 1;
1713 goto no_relems;
1714 }
1715
a0d0e21e 1716 default:
8b0c3377
DM
1717 if (!SvIMMORTAL(lsv)) {
1718 if (UNLIKELY(
1719 SvTEMP(lsv) && !SvSMAGICAL(lsv) && SvREFCNT(lsv) == 1 &&
1720 (!isGV_with_GP(lsv) || SvFAKE(lsv)) && ckWARN(WARN_MISC)
1721 ))
1722 Perl_warner(aTHX_
1723 packWARN(WARN_MISC),
1724 "Useless assignment to a temporary"
1725 );
1726 sv_setsv(lsv, *relem);
1727 *relem = lsv;
1728 SvSETMAGIC(lsv);
1729 }
1730 if (++relem > lastrelem)
1731 goto no_relems;
a0d0e21e 1732 break;
8b0c3377
DM
1733 } /* switch */
1734 } /* while */
1735
1736
1737 no_relems:
1738
1739 /* simplified lelem loop for when there are no relems left */
1740 while (LIKELY(lelem <= lastlelem)) {
1741 SV *lsv = *lelem++;
1742 if (UNLIKELY(!lsv)) {
1743 lsv = *lelem++;
1744 ASSUME(SvTYPE(lsv) == SVt_PVAV);
a0d0e21e 1745 }
8b0c3377
DM
1746
1747 switch (SvTYPE(lsv)) {
1748 case SVt_PVAV:
1749 ary = MUTABLE_AV(lsv);
1750 if (SvRMAGICAL(ary) || AvFILLp(ary) >= 0) {
1751 av_clear(ary);
1752 if (UNLIKELY(PL_delaymagic & DM_ARRAY_ISA))
1753 SvSETMAGIC(MUTABLE_SV(ary));
1754 }
1755 break;
1756
1757 case SVt_PVHV:
1758 hash = MUTABLE_HV(lsv);
1759 if (SvRMAGICAL(hash) || HvUSEDKEYS(hash))
1760 hv_clear(hash);
1761 break;
1762
1763 default:
1764 if (!SvIMMORTAL(lsv)) {
1765 sv_setsv(lsv, &PL_sv_undef);
1766 SvSETMAGIC(lsv);
1767 }
1768 break;
1769 } /* switch */
1770 } /* while */
1771
5d9574c1 1772 if (UNLIKELY(PL_delaymagic & ~DM_DELAY)) {
985213f2 1773 /* Will be used to set PL_tainting below */
dfff4baf
BF
1774 Uid_t tmp_uid = PerlProc_getuid();
1775 Uid_t tmp_euid = PerlProc_geteuid();
1776 Gid_t tmp_gid = PerlProc_getgid();
1777 Gid_t tmp_egid = PerlProc_getegid();
985213f2 1778
b469f1e0 1779 /* XXX $> et al currently silently ignore failures */
3280af22 1780 if (PL_delaymagic & DM_UID) {
a0d0e21e 1781#ifdef HAS_SETRESUID
b469f1e0
JH
1782 PERL_UNUSED_RESULT(
1783 setresuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
1784 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1,
1785 (Uid_t)-1));
56febc5e
AD
1786#else
1787# ifdef HAS_SETREUID
b469f1e0
JH
1788 PERL_UNUSED_RESULT(
1789 setreuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
1790 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1));
56febc5e
AD
1791# else
1792# ifdef HAS_SETRUID
b28d0864 1793 if ((PL_delaymagic & DM_UID) == DM_RUID) {
b469f1e0 1794 PERL_UNUSED_RESULT(setruid(PL_delaymagic_uid));
b28d0864 1795 PL_delaymagic &= ~DM_RUID;
a0d0e21e 1796 }
56febc5e
AD
1797# endif /* HAS_SETRUID */
1798# ifdef HAS_SETEUID
b28d0864 1799 if ((PL_delaymagic & DM_UID) == DM_EUID) {
b469f1e0 1800 PERL_UNUSED_RESULT(seteuid(PL_delaymagic_euid));
b28d0864 1801 PL_delaymagic &= ~DM_EUID;
a0d0e21e 1802 }
56febc5e 1803# endif /* HAS_SETEUID */
b28d0864 1804 if (PL_delaymagic & DM_UID) {
985213f2 1805 if (PL_delaymagic_uid != PL_delaymagic_euid)
cea2e8a9 1806 DIE(aTHX_ "No setreuid available");
b469f1e0 1807 PERL_UNUSED_RESULT(PerlProc_setuid(PL_delaymagic_uid));
a0d0e21e 1808 }
56febc5e
AD
1809# endif /* HAS_SETREUID */
1810#endif /* HAS_SETRESUID */
04783dc7 1811
985213f2
AB
1812 tmp_uid = PerlProc_getuid();
1813 tmp_euid = PerlProc_geteuid();
a0d0e21e 1814 }
b469f1e0 1815 /* XXX $> et al currently silently ignore failures */
3280af22 1816 if (PL_delaymagic & DM_GID) {
a0d0e21e 1817#ifdef HAS_SETRESGID
b469f1e0
JH
1818 PERL_UNUSED_RESULT(
1819 setresgid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
1820 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1,
1821 (Gid_t)-1));
56febc5e
AD
1822#else
1823# ifdef HAS_SETREGID
b469f1e0
JH
1824 PERL_UNUSED_RESULT(
1825 setregid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
1826 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1));
56febc5e
AD
1827# else
1828# ifdef HAS_SETRGID
b28d0864 1829 if ((PL_delaymagic & DM_GID) == DM_RGID) {
b469f1e0 1830 PERL_UNUSED_RESULT(setrgid(PL_delaymagic_gid));
b28d0864 1831 PL_delaymagic &= ~DM_RGID;
a0d0e21e 1832 }
56febc5e
AD
1833# endif /* HAS_SETRGID */
1834# ifdef HAS_SETEGID
b28d0864 1835 if ((PL_delaymagic & DM_GID) == DM_EGID) {
b469f1e0 1836 PERL_UNUSED_RESULT(setegid(PL_delaymagic_egid));
b28d0864 1837 PL_delaymagic &= ~DM_EGID;
a0d0e21e 1838 }
56febc5e 1839# endif /* HAS_SETEGID */
b28d0864 1840 if (PL_delaymagic & DM_GID) {
985213f2 1841 if (PL_delaymagic_gid != PL_delaymagic_egid)
cea2e8a9 1842 DIE(aTHX_ "No setregid available");
b469f1e0 1843 PERL_UNUSED_RESULT(PerlProc_setgid(PL_delaymagic_gid));
a0d0e21e 1844 }
56febc5e
AD
1845# endif /* HAS_SETREGID */
1846#endif /* HAS_SETRESGID */
04783dc7 1847
985213f2
AB
1848 tmp_gid = PerlProc_getgid();
1849 tmp_egid = PerlProc_getegid();
a0d0e21e 1850 }
284167a5 1851 TAINTING_set( TAINTING_get | (tmp_uid && (tmp_euid != tmp_uid || tmp_egid != tmp_gid)) );
9a9b5ec9
DM
1852#ifdef NO_TAINT_SUPPORT
1853 PERL_UNUSED_VAR(tmp_uid);
1854 PERL_UNUSED_VAR(tmp_euid);
1855 PERL_UNUSED_VAR(tmp_gid);
1856 PERL_UNUSED_VAR(tmp_egid);
1857#endif
a0d0e21e 1858 }
a68090fe 1859 PL_delaymagic = old_delaymagic;
54310121 1860
54310121
PP
1861 if (gimme == G_VOID)
1862 SP = firstrelem - 1;
1863 else if (gimme == G_SCALAR) {
1864 dTARGET;
1865 SP = firstrelem;
8b0c3377 1866 SETi(firstlelem - firstrelem);
54310121
PP
1867 }
1868 else {
1c4ea384 1869 if (ary || hash)
1d2b3927
HS
1870 /* note that in this case *firstlelem may have been overwritten
1871 by sv_undef in the odd hash case */
a0d0e21e 1872 SP = lastrelem;
1c4ea384 1873 else {
a0d0e21e 1874 SP = firstrelem + (lastlelem - firstlelem);
1c4ea384
RZ
1875 lelem = firstlelem + (relem - firstrelem);
1876 while (relem <= SP)
1877 *relem++ = (lelem <= lastlelem) ? *lelem++ : &PL_sv_undef;
1878 }
a0d0e21e 1879 }
08aeb9f7 1880
54310121 1881 RETURN;
a0d0e21e
LW
1882}
1883
8782bef2
GB
1884PP(pp_qr)
1885{
20b7effb 1886 dSP;
eb578fdb 1887 PMOP * const pm = cPMOP;
fe578d7f 1888 REGEXP * rx = PM_GETRE(pm);
10599a69 1889 SV * const pkg = rx ? CALLREG_PACKAGE(rx) : NULL;
c4420975 1890 SV * const rv = sv_newmortal();
d63c20f2
DM
1891 CV **cvp;
1892 CV *cv;
288b8c02
NC
1893
1894 SvUPGRADE(rv, SVt_IV);
c2123ae3
NC
1895 /* For a subroutine describing itself as "This is a hacky workaround" I'm
1896 loathe to use it here, but it seems to be the right fix. Or close.
1897 The key part appears to be that it's essential for pp_qr to return a new
1898 object (SV), which implies that there needs to be an effective way to
1899 generate a new SV from the existing SV that is pre-compiled in the
1900 optree. */
1901 SvRV_set(rv, MUTABLE_SV(reg_temp_copy(NULL, rx)));
288b8c02
NC
1902 SvROK_on(rv);
1903
8d919b0a 1904 cvp = &( ReANY((REGEXP *)SvRV(rv))->qr_anoncv);
5d9574c1 1905 if (UNLIKELY((cv = *cvp) && CvCLONE(*cvp))) {
d63c20f2 1906 *cvp = cv_clone(cv);
fc2b2dca 1907 SvREFCNT_dec_NN(cv);
d63c20f2
DM
1908 }
1909
288b8c02 1910 if (pkg) {
f815daf2 1911 HV *const stash = gv_stashsv(pkg, GV_ADD);
fc2b2dca 1912 SvREFCNT_dec_NN(pkg);
288b8c02
NC
1913 (void)sv_bless(rv, stash);
1914 }
1915
5d9574c1 1916 if (UNLIKELY(RX_ISTAINTED(rx))) {
e08e52cf 1917 SvTAINTED_on(rv);
9274aefd
DM
1918 SvTAINTED_on(SvRV(rv));
1919 }
c8c13c22 1920 XPUSHs(rv);
1921 RETURN;
8782bef2
GB
1922}
1923
a0d0e21e
LW
1924PP(pp_match)
1925{
20b7effb 1926 dSP; dTARG;
eb578fdb 1927 PMOP *pm = cPMOP;
d65afb4b 1928 PMOP *dynpm = pm;
eb578fdb 1929 const char *s;
5c144d81 1930 const char *strend;
99a90e59 1931 SSize_t curpos = 0; /* initial pos() or current $+[0] */
a0d0e21e 1932 I32 global;
7fadf4a7 1933 U8 r_flags = 0;
5c144d81 1934 const char *truebase; /* Start of string */
eb578fdb 1935 REGEXP *rx = PM_GETRE(pm);
b3eb6a9b 1936 bool rxtainted;
1c23e2bd 1937 const U8 gimme = GIMME_V;
a0d0e21e 1938 STRLEN len;
a3b680e6 1939 const I32 oldsave = PL_savestack_ix;
e60df1fa 1940 I32 had_zerolen = 0;
b1422d62 1941 MAGIC *mg = NULL;
a0d0e21e 1942
533c011a 1943 if (PL_op->op_flags & OPf_STACKED)
a0d0e21e 1944 TARG = POPs;
6ffceeb7 1945 else if (ARGTARG)
59f00321 1946 GETTARGET;
a0d0e21e 1947 else {
54b9620d 1948 TARG = DEFSV;
a0d0e21e
LW
1949 EXTEND(SP,1);
1950 }
d9f424b2 1951
c277df42 1952 PUTBACK; /* EVAL blocks need stack_sp. */
69dc4b30
FC
1953 /* Skip get-magic if this is a qr// clone, because regcomp has
1954 already done it. */
f1d31338 1955 truebase = ReANY(rx)->mother_re
69dc4b30
FC
1956 ? SvPV_nomg_const(TARG, len)
1957 : SvPV_const(TARG, len);
f1d31338 1958 if (!truebase)
2269b42e 1959 DIE(aTHX_ "panic: pp_match");
f1d31338 1960 strend = truebase + len;
284167a5
SM
1961 rxtainted = (RX_ISTAINTED(rx) ||
1962 (TAINT_get && (pm->op_pmflags & PMf_RETAINT)));
9212bbba 1963 TAINT_NOT;
a0d0e21e 1964
6c864ec2 1965 /* We need to know this in case we fail out early - pos() must be reset */
de0df3c0
MH
1966 global = dynpm->op_pmflags & PMf_GLOBAL;
1967
d65afb4b 1968 /* PMdf_USED is set after a ?? matches once */
c737faaf
YO
1969 if (
1970#ifdef USE_ITHREADS
1971 SvREADONLY(PL_regex_pad[pm->op_pmoffset])
1972#else
1973 pm->op_pmflags & PMf_USED
1974#endif
1975 ) {
e5dc5375 1976 DEBUG_r(PerlIO_printf(Perl_debug_log, "?? already matched once"));
de0df3c0 1977 goto nope;
a0d0e21e
LW
1978 }
1979
7e313637
FC
1980 /* empty pattern special-cased to use last successful pattern if
1981 possible, except for qr// */
794826f4
YO
1982 if (!ReANY(rx)->mother_re && !RX_PRELEN(rx) && PL_curpm) {
1983 if (PL_curpm == PL_reg_curpm)
31775478 1984 Perl_croak(aTHX_ "Use of the empty pattern inside of "
794826f4 1985 "a regex code block is forbidden");
3280af22 1986 pm = PL_curpm;
aaa362c4 1987 rx = PM_GETRE(pm);
a0d0e21e 1988 }
d65afb4b 1989
389ecb56 1990 if (RX_MINLEN(rx) >= 0 && (STRLEN)RX_MINLEN(rx) > len) {
75d43e96
FC
1991 DEBUG_r(PerlIO_printf(Perl_debug_log, "String shorter than min possible regex match (%"
1992 UVuf" < %"IVdf")\n",
1993 (UV)len, (IV)RX_MINLEN(rx)));
de0df3c0 1994 goto nope;
e5dc5375 1995 }
c277df42 1996
8ef97b0e 1997 /* get pos() if //g */
de0df3c0 1998 if (global) {
b1422d62 1999 mg = mg_find_mglob(TARG);
8ef97b0e 2000 if (mg && mg->mg_len >= 0) {
25fdce4a 2001 curpos = MgBYTEPOS(mg, TARG, truebase, len);
8ef97b0e
DM
2002 /* last time pos() was set, it was zero-length match */
2003 if (mg->mg_flags & MGf_MINMATCH)
2004 had_zerolen = 1;
2005 }
a0d0e21e 2006 }
8ef97b0e 2007
6e240d0b 2008#ifdef PERL_SAWAMPERSAND
a41aa44d 2009 if ( RX_NPARENS(rx)
6502e081 2010 || PL_sawampersand
6502e081 2011 || (RX_EXTFLAGS(rx) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
5b0e71e9 2012 || (dynpm->op_pmflags & PMf_KEEPCOPY)
6e240d0b
FC
2013 )
2014#endif
2015 {
6502e081
DM
2016 r_flags |= (REXEC_COPY_STR|REXEC_COPY_SKIP_PRE);
2017 /* in @a =~ /(.)/g, we iterate multiple times, but copy the buffer
2018 * only on the first iteration. Therefore we need to copy $' as well
2019 * as $&, to make the rest of the string available for captures in
2020 * subsequent iterations */
2021 if (! (global && gimme == G_ARRAY))
2022 r_flags |= REXEC_COPY_SKIP_POST;
2023 };
5b0e71e9
DM
2024#ifdef PERL_SAWAMPERSAND
2025 if (dynpm->op_pmflags & PMf_KEEPCOPY)
2026 /* handle KEEPCOPY in pmop but not rx, eg $r=qr/a/; /$r/p */
2027 r_flags &= ~(REXEC_COPY_SKIP_PRE|REXEC_COPY_SKIP_POST);
2028#endif
22e551b9 2029
f1d31338
DM
2030 s = truebase;
2031
d7be1480 2032 play_it_again:
985afbc1 2033 if (global)
03c83e26 2034 s = truebase + curpos;
f722798b 2035
77da2310 2036 if (!CALLREGEXEC(rx, (char*)s, (char *)strend, (char*)truebase,
03c83e26 2037 had_zerolen, TARG, NULL, r_flags))
03b6c93d 2038 goto nope;
77da2310
NC
2039
2040 PL_curpm = pm;
985afbc1 2041 if (dynpm->op_pmflags & PMf_ONCE)
c737faaf 2042#ifdef USE_ITHREADS
77da2310 2043 SvREADONLY_on(PL_regex_pad[dynpm->op_pmoffset]);
c737faaf 2044#else
77da2310 2045 dynpm->op_pmflags |= PMf_USED;
c737faaf 2046#endif
a0d0e21e 2047
72311751
GS
2048 if (rxtainted)
2049 RX_MATCH_TAINTED_on(rx);
2050 TAINT_IF(RX_MATCH_TAINTED(rx));
35c2ccc3
DM
2051
2052 /* update pos */
2053
2054 if (global && (gimme != G_ARRAY || (dynpm->op_pmflags & PMf_CONTINUE))) {
b1422d62 2055 if (!mg)
35c2ccc3 2056 mg = sv_magicext_mglob(TARG);
25fdce4a 2057 MgBYTEPOS_set(mg, TARG, truebase, RX_OFFS(rx)[0].end);
adf51885
DM
2058 if (RX_ZERO_LEN(rx))
2059 mg->mg_flags |= MGf_MINMATCH;
2060 else
2061 mg->mg_flags &= ~MGf_MINMATCH;
35c2ccc3
DM
2062 }
2063
bf9dff51
DM
2064 if ((!RX_NPARENS(rx) && !global) || gimme != G_ARRAY) {
2065 LEAVE_SCOPE(oldsave);
2066 RETPUSHYES;
2067 }
2068
88ab22af
DM
2069 /* push captures on stack */
2070
bf9dff51 2071 {
07bc277f 2072 const I32 nparens = RX_NPARENS(rx);
a3b680e6 2073 I32 i = (global && !nparens) ? 1 : 0;
a0d0e21e 2074
c277df42 2075 SPAGAIN; /* EVAL blocks could move the stack. */
ffc61ed2
JH
2076 EXTEND(SP, nparens + i);
2077 EXTEND_MORTAL(nparens + i);
2078 for (i = !i; i <= nparens; i++) {
a0d0e21e 2079 PUSHs(sv_newmortal());
5d9574c1
DM
2080 if (LIKELY((RX_OFFS(rx)[i].start != -1)
2081 && RX_OFFS(rx)[i].end != -1 ))
2082 {
07bc277f 2083 const I32 len = RX_OFFS(rx)[i].end - RX_OFFS(rx)[i].start;
f1d31338 2084 const char * const s = RX_OFFS(rx)[i].start + truebase;
5d9574c1
DM
2085 if (UNLIKELY(RX_OFFS(rx)[i].end < 0 || RX_OFFS(rx)[i].start < 0
2086 || len < 0 || len > strend - s))
5637ef5b
NC
2087 DIE(aTHX_ "panic: pp_match start/end pointers, i=%ld, "
2088 "start=%ld, end=%ld, s=%p, strend=%p, len=%"UVuf,
2089 (long) i, (long) RX_OFFS(rx)[i].start,
2090 (long)RX_OFFS(rx)[i].end, s, strend, (UV) len);
a0d0e21e 2091 sv_setpvn(*SP, s, len);
cce850e4 2092 if (DO_UTF8(TARG) && is_utf8_string((U8*)s, len))
a197cbdd 2093 SvUTF8_on(*SP);
a0d0e21e
LW
2094 }
2095 }
2096 if (global) {
0e0b3e82 2097 curpos = (UV)RX_OFFS(rx)[0].end;
03c83e26 2098 had_zerolen = RX_ZERO_LEN(rx);
c277df42 2099 PUTBACK; /* EVAL blocks may use stack */
cf93c79d 2100 r_flags |= REXEC_IGNOREPOS | REXEC_NOT_FIRST;
a0d0e21e
LW
2101 goto play_it_again;
2102 }
4633a7c4 2103 LEAVE_SCOPE(oldsave);
a0d0e21e
LW
2104 RETURN;
2105 }
e5964223 2106 NOT_REACHED; /* NOTREACHED */
a0d0e21e 2107
7b52d656 2108 nope:
d65afb4b 2109 if (global && !(dynpm->op_pmflags & PMf_CONTINUE)) {
b1422d62
DM
2110 if (!mg)
2111 mg = mg_find_mglob(TARG);
2112 if (mg)
2113 mg->mg_len = -1;
a0d0e21e 2114 }
4633a7c4 2115 LEAVE_SCOPE(oldsave);
a0d0e21e
LW
2116 if (gimme == G_ARRAY)
2117 RETURN;
2118 RETPUSHNO;
2119}
2120
2121OP *
864dbfa3 2122Perl_do_readline(pTHX)
a0d0e21e 2123{
20b7effb 2124 dSP; dTARGETSTACKED;
eb578fdb 2125 SV *sv;
a0d0e21e
LW
2126 STRLEN tmplen = 0;
2127 STRLEN offset;
760ac839 2128 PerlIO *fp;
eb578fdb
KW
2129 IO * const io = GvIO(PL_last_in_gv);
2130 const I32 type = PL_op->op_type;
1c23e2bd 2131 const U8 gimme = GIMME_V;
a0d0e21e 2132
6136c704 2133 if (io) {
50db69d8 2134 const MAGIC *const mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar);
6136c704 2135 if (mg) {
3e0cb5de 2136 Perl_tied_method(aTHX_ SV_CONST(READLINE), SP, MUTABLE_SV(io), mg, gimme, 0);
6136c704 2137 if (gimme == G_SCALAR) {
50db69d8
NC
2138 SPAGAIN;
2139 SvSetSV_nosteal(TARG, TOPs);
2140 SETTARG;
6136c704 2141 }
50db69d8 2142 return NORMAL;
0b7c7b4f 2143 }
e79b0511 2144 }
4608196e 2145 fp = NULL;
a0d0e21e
LW
2146 if (io) {
2147 fp = IoIFP(io);
2148 if (!fp) {
2149 if (IoFLAGS(io) & IOf_ARGV) {
2150 if (IoFLAGS(io) & IOf_START) {
a0d0e21e 2151 IoLINES(io) = 0;
b9f2b683 2152 if (av_tindex(GvAVn(PL_last_in_gv)) < 0) {
1d7c1841 2153 IoFLAGS(io) &= ~IOf_START;
d5eb9a46 2154 do_open6(PL_last_in_gv, "-", 1, NULL, NULL, 0);
4bac9ae4 2155 SvTAINTED_off(GvSVn(PL_last_in_gv)); /* previous tainting irrelevant */
76f68e9b 2156 sv_setpvs(GvSVn(PL_last_in_gv), "-");
3280af22 2157 SvSETMAGIC(GvSV(PL_last_in_gv));
a2008d6d
GS
2158 fp = IoIFP(io);
2159 goto have_fp;
a0d0e21e
LW
2160 }
2161 }
157fb5a1 2162 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
a0d0e21e 2163 if (!fp) { /* Note: fp != IoIFP(io) */
3280af22 2164 (void)do_close(PL_last_in_gv, FALSE); /* now it does*/
a0d0e21e
LW
2165 }
2166 }
0d44d22b
NC
2167 else if (type == OP_GLOB)
2168 fp = Perl_start_glob(aTHX_ POPs, io);
a0d0e21e
LW
2169 }
2170 else if (type == OP_GLOB)
2171 SP--;
7716c5c5 2172 else if (IoTYPE(io) == IoTYPE_WRONLY) {
a5390457 2173 report_wrongway_fh(PL_last_in_gv, '>');
a00b5bd3 2174 }
a0d0e21e
LW
2175 }
2176 if (!fp) {
041457d9 2177 if ((!io || !(IoFLAGS(io) & IOf_START))
de7dabb6
TC
2178 && ckWARN(WARN_CLOSED)
2179 && type != OP_GLOB)
041457d9 2180 {
de7dabb6 2181 report_evil_fh(PL_last_in_gv);
3f4520fe 2182 }
54310121 2183 if (gimme == G_SCALAR) {
79628082 2184 /* undef TARG, and push that undefined value */
ba92458f 2185 if (type != OP_RCATLINE) {
aab1202a 2186 sv_setsv(TARG,NULL);
ba92458f 2187 }
a0d0e21e
LW
2188 PUSHTARG;
2189 }
2190 RETURN;
2191 }
a2008d6d 2192 have_fp:
54310121 2193 if (gimme == G_SCALAR) {
a0d0e21e 2194 sv = TARG;
0f722b55
RGS
2195 if (type == OP_RCATLINE && SvGMAGICAL(sv))
2196 mg_get(sv);
48de12d9
RGS
2197 if (SvROK(sv)) {
2198 if (type == OP_RCATLINE)
5668452f 2199 SvPV_force_nomg_nolen(sv);
48de12d9
RGS
2200 else
2201 sv_unref(sv);
2202 }
f7877b28 2203 else if (isGV_with_GP(sv)) {
5668452f 2204 SvPV_force_nomg_nolen(sv);
f7877b28 2205 }
862a34c6 2206 SvUPGRADE(sv, SVt_PV);
a0d0e21e 2207 tmplen = SvLEN(sv); /* remember if already alloced */
e3918bb7 2208 if (!tmplen && !SvREADONLY(sv) && !SvIsCOW(sv)) {
f72e8700
JJ
2209 /* try short-buffering it. Please update t/op/readline.t
2210 * if you change the growth length.
2211 */
2212 Sv_Grow(sv, 80);
2213 }
2b5e58c4
AMS
2214 offset = 0;
2215 if (type == OP_RCATLINE && SvOK(sv)) {
2216 if (!SvPOK(sv)) {
5668452f 2217 SvPV_force_nomg_nolen(sv);
2b5e58c4 2218 }
a0d0e21e 2219 offset = SvCUR(sv);
2b5e58c4 2220 }
a0d0e21e 2221 }
54310121 2222 else {
561b68a9 2223 sv = sv_2mortal(newSV(80));
54310121
PP
2224 offset = 0;
2225 }
fbad3eb5 2226
3887d568
AP
2227 /* This should not be marked tainted if the fp is marked clean */
2228#define MAYBE_TAINT_LINE(io, sv) \
2229 if (!(IoFLAGS(io) & IOf_UNTAINT)) { \
2230 TAINT; \
2231 SvTAINTED_on(sv); \
2232 }
2233
684bef36 2234/* delay EOF state for a snarfed empty file */
fbad3eb5 2235#define SNARF_EOF(gimme,rs,io,sv) \
684bef36 2236 (gimme != G_SCALAR || SvCUR(sv) \
b9fee9ba 2237 || (IoFLAGS(io) & IOf_NOLINE) || !RsSNARF(rs))
fbad3eb5 2238
a0d0e21e 2239 for (;;) {
09e8efcc 2240 PUTBACK;
fbad3eb5 2241 if (!sv_gets(sv, fp, offset)
2d726892
TF
2242 && (type == OP_GLOB
2243 || SNARF_EOF(gimme, PL_rs, io, sv)
2244 || PerlIO_error(fp)))
fbad3eb5 2245 {
760ac839 2246 PerlIO_clearerr(fp);
a0d0e21e 2247 if (IoFLAGS(io) & IOf_ARGV) {
157fb5a1 2248 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
a0d0e21e
LW
2249 if (fp)
2250 continue;
3280af22 2251 (void)do_close(PL_last_in_gv, FALSE);
a0d0e21e
LW
2252 }
2253 else if (type == OP_GLOB) {
a2a5de95
NC
2254 if (!do_close(PL_last_in_gv, FALSE)) {
2255 Perl_ck_warner(aTHX_ packWARN(WARN_GLOB),
2256 "glob failed (child exited with status %d%s)",
2257 (int)(STATUS_CURRENT >> 8),
2258 (STATUS_CURRENT & 0x80) ? ", core dumped" : "");
4eb79ab5 2259 }
a0d0e21e 2260 }
54310121 2261 if (gimme == G_SCALAR) {
ba92458f
AE
2262 if (type != OP_RCATLINE) {
2263 SV_CHECK_THINKFIRST_COW_DROP(TARG);
0c34ef67 2264 SvOK_off(TARG);
ba92458f 2265 }
09e8efcc 2266 SPAGAIN;
a0d0e21e
LW
2267 PUSHTARG;
2268 }
3887d568 2269 MAYBE_TAINT_LINE(io, sv);
a0d0e21e
LW
2270 RETURN;
2271 }
3887d568 2272 MAYBE_TAINT_LINE(io, sv);
a0d0e21e 2273 IoLINES(io)++;
b9fee9ba 2274 IoFLAGS(io) |= IOf_NOLINE;
71be2cbc 2275 SvSETMAGIC(sv);
09e8efcc 2276 SPAGAIN;
a0d0e21e 2277 XPUSHs(sv);
a0d0e21e 2278 if (type == OP_GLOB) {
349d4f2f 2279 const char *t1;
45a23732 2280 Stat_t statbuf;
a0d0e21e 2281
3280af22 2282 if (SvCUR(sv) > 0 && SvCUR(PL_rs) > 0) {
6136c704 2283 char * const tmps = SvEND(sv) - 1;
aa07b2f6 2284 if (*tmps == *SvPVX_const(PL_rs)) {
c07a80fd 2285 *tmps = '\0';
b162af07 2286 SvCUR_set(sv, SvCUR(sv) - 1);
c07a80fd
PP
2287 }
2288 }
349d4f2f 2289 for (t1 = SvPVX_const(sv); *t1; t1++)
b51c3e77
CB
2290#ifdef __VMS
2291 if (strchr("*%?", *t1))
2292#else
7ad1e72d 2293 if (strchr("$&*(){}[]'\";\\|?<>~`", *t1))
b51c3e77 2294#endif
a0d0e21e 2295 break;
45a23732 2296 if (*t1 && PerlLIO_lstat(SvPVX_const(sv), &statbuf) < 0) {
a0d0e21e
LW
2297 (void)POPs; /* Unmatched wildcard? Chuck it... */
2298 continue;
2299 }
2d79bf7f 2300 } else if (SvUTF8(sv)) { /* OP_READLINE, OP_RCATLINE */
d4c19fe8
AL
2301 if (ckWARN(WARN_UTF8)) {
2302 const U8 * const s = (const U8*)SvPVX_const(sv) + offset;
2303 const STRLEN len = SvCUR(sv) - offset;
2304 const U8 *f;
2305
2306 if (!is_utf8_string_loc(s, len, &f))
2307 /* Emulate :encoding(utf8) warning in the same case. */
2308 Perl_warner(aTHX_ packWARN(WARN_UTF8),
2309 "utf8 \"\\x%02X\" does not map to Unicode",
2310 f < (U8*)SvEND(sv) ? *f : 0);
2311 }
a0d0e21e 2312 }
54310121 2313 if (gimme == G_ARRAY) {
a0d0e21e 2314 if (SvLEN(sv) - SvCUR(sv) > 20) {
1da4ca5f 2315 SvPV_shrink_to_cur(sv);
a0d0e21e 2316 }
561b68a9 2317 sv = sv_2mortal(newSV(80));
a0d0e21e
LW
2318 continue;
2319 }
54310121 2320 else if (gimme == G_SCALAR && !tmplen && SvLEN(sv) - SvCUR(sv) > 80) {
a0d0e21e 2321 /* try to reclaim a bit of scalar space (only on 1st alloc) */
d5b5861b
NC
2322 const STRLEN new_len
2323 = SvCUR(sv) < 60 ? 80 : SvCUR(sv)+40; /* allow some slop */
1da4ca5f 2324 SvPV_renew(sv, new_len);
a0d0e21e
LW
2325 }
2326 RETURN;
2327 }
2328}
2329
a0d0e21e
LW
2330PP(pp_helem)
2331{
20b7effb 2332 dSP;
760ac839 2333 HE* he;
ae77835f 2334 SV **svp;
c445ea15 2335 SV * const keysv = POPs;
85fbaab2 2336 HV * const hv = MUTABLE_HV(POPs);
a3b680e6
AL
2337 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2338 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
be6c24e0 2339 SV *sv;
92970b93 2340 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
d30e492c 2341 bool preeminent = TRUE;
a0d0e21e 2342
6dfc73ea
SM
2343 if (SvTYPE(hv) != SVt_PVHV)
2344 RETPUSHUNDEF;
d4c19fe8 2345
92970b93 2346 if (localizing) {
d4c19fe8
AL
2347 MAGIC *mg;
2348 HV *stash;
d30e492c
VP
2349
2350 /* If we can determine whether the element exist,
2351 * Try to preserve the existenceness of a tied hash
2352 * element by using EXISTS and DELETE if possible.
2353 * Fallback to FETCH and STORE otherwise. */
2c5f48c2 2354 if (SvCANEXISTDELETE(hv))
d30e492c 2355 preeminent = hv_exists_ent(hv, keysv, 0);
d4c19fe8 2356 }
d30e492c 2357
5f9d7e2b 2358 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
d4c19fe8 2359 svp = he ? &HeVAL(he) : NULL;
a0d0e21e 2360 if (lval) {
746f6409 2361 if (!svp || !*svp || *svp == &PL_sv_undef) {
68dc0745
PP
2362 SV* lv;
2363 SV* key2;
2d8e6c8d 2364 if (!defer) {
be2597df 2365 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2d8e6c8d 2366 }
68dc0745
PP
2367 lv = sv_newmortal();
2368 sv_upgrade(lv, SVt_PVLV);
2369 LvTYPE(lv) = 'y';
6136c704 2370 sv_magic(lv, key2 = newSVsv(keysv), PERL_MAGIC_defelem, NULL, 0);
fc2b2dca 2371 SvREFCNT_dec_NN(key2); /* sv_magic() increments refcount */
0ad694a7 2372 LvTARG(lv) = SvREFCNT_inc_simple_NN(hv);
68dc0745
PP
2373 LvTARGLEN(lv) = 1;
2374 PUSHs(lv);
2375 RETURN;
2376 }
92970b93 2377 if (localizing) {
bfcb3514 2378 if (HvNAME_get(hv) && isGV(*svp))
159b6efe 2379 save_gp(MUTABLE_GV(*svp), !(PL_op->op_flags & OPf_SPECIAL));
47cfc530
VP
2380 else if (preeminent)
2381 save_helem_flags(hv, keysv, svp,
2382 (PL_op->op_flags & OPf_SPECIAL) ? 0 : SAVEf_SETMAGIC);
2383 else
2384 SAVEHDELETE(hv, keysv);
5f05dabc 2385 }
9026059d
GG
2386 else if (PL_op->op_private & OPpDEREF) {
2387 PUSHs(vivify_ref(*svp, PL_op->op_private & OPpDEREF));
2388 RETURN;
2389 }
a0d0e21e 2390 }
746f6409 2391 sv = (svp && *svp ? *svp : &PL_sv_undef);
fd69380d
DM
2392 /* Originally this did a conditional C<sv = sv_mortalcopy(sv)>; this
2393 * was to make C<local $tied{foo} = $tied{foo}> possible.
2394 * However, it seems no longer to be needed for that purpose, and
2395 * introduced a new bug: stuff like C<while ($hash{taintedval} =~ /.../g>
2396 * would loop endlessly since the pos magic is getting set on the
2397 * mortal copy and lost. However, the copy has the effect of
2398 * triggering the get magic, and losing it altogether made things like
2399 * c<$tied{foo};> in void context no longer do get magic, which some
2400 * code relied on. Also, delayed triggering of magic on @+ and friends
2401 * meant the original regex may be out of scope by now. So as a
2402 * compromise, do the get magic here. (The MGf_GSKIP flag will stop it
2403 * being called too many times). */
39cf747a 2404 if (!lval && SvRMAGICAL(hv) && SvGMAGICAL(sv))
fd69380d 2405 mg_get(sv);
be6c24e0 2406 PUSHs(sv);
a0d0e21e
LW
2407 RETURN;
2408}
2409
fedf30e1
DM
2410
2411/* a stripped-down version of Perl_softref2xv() for use by
2412 * pp_multideref(), which doesn't use PL_op->op_flags */
2413
f9db5646 2414STATIC GV *
fedf30e1
DM
2415S_softref2xv_lite(pTHX_ SV *const sv, const char *const what,
2416 const svtype type)
2417{
2418 if (PL_op->op_private & HINT_STRICT_REFS) {
2419 if (SvOK(sv))
2420 Perl_die(aTHX_ PL_no_symref_sv, sv,
2421 (SvPOKp(sv) && SvCUR(sv)>32 ? "..." : ""), what);
2422 else
2423 Perl_die(aTHX_ PL_no_usym, what);
2424 }
2425 if (!SvOK(sv))
2426 Perl_die(aTHX_ PL_no_usym, what);
2427 return gv_fetchsv_nomg(sv, GV_ADD, type);
2428}
2429
2430
79815f56
DM
2431/* Handle one or more aggregate derefs and array/hash indexings, e.g.
2432 * $h->{foo} or $a[0]{$key}[$i] or f()->[1]
fedf30e1
DM
2433 *
2434 * op_aux points to an array of unions of UV / IV / SV* / PADOFFSET.
79815f56
DM
2435 * Each of these either contains a set of actions, or an argument, such as
2436 * an IV to use as an array index, or a lexical var to retrieve.
2437 * Several actions re stored per UV; we keep shifting new actions off the
2438 * one UV, and only reload when it becomes zero.
fedf30e1
DM
2439 */
2440
2441PP(pp_multideref)
2442{
2443 SV *sv = NULL; /* init to avoid spurious 'may be used uninitialized' */
2444 UNOP_AUX_item *items = cUNOP_AUXx(PL_op)->op_aux;
2445 UV actions = items->uv;
2446
2447 assert(actions);
2448 /* this tells find_uninit_var() where we're up to */
2449 PL_multideref_pc = items;
2450
2451 while (1) {
2452 /* there are three main classes of action; the first retrieve
2453 * the initial AV or HV from a variable or the stack; the second
2454 * does the equivalent of an unrolled (/DREFAV, rv2av, aelem),
2455 * the third an unrolled (/DREFHV, rv2hv, helem).
2456 */
2457 switch (actions & MDEREF_ACTION_MASK) {
2458
2459 case MDEREF_reload:
2460 actions = (++items)->uv;
2461 continue;
2462
2463 case MDEREF_AV_padav_aelem: /* $lex[...] */
2464 sv = PAD_SVl((++items)->pad_offset);
2465 goto do_AV_aelem;
2466
2467 case MDEREF_AV_gvav_aelem: /* $pkg[...] */
2468 sv = UNOP_AUX_item_sv(++items);
2469 assert(isGV_with_GP(sv));
2470 sv = (SV*)GvAVn((GV*)sv);
2471 goto do_AV_aelem;
2472
2473 case MDEREF_AV_pop_rv2av_aelem: /* expr->[...] */
2474 {
2475 dSP;
2476 sv = POPs;
2477 PUTBACK;
2478 goto do_AV_rv2av_aelem;
2479 }
2480
2481 case MDEREF_AV_gvsv_vivify_rv2av_aelem: /* $pkg->[...] */
2482 sv = UNOP_AUX_item_sv(++items);
2483 assert(isGV_with_GP(sv));
2484 sv = GvSVn((GV*)sv);
2485 goto do_AV_vivify_rv2av_aelem;
2486
2487 case MDEREF_AV_padsv_vivify_rv2av_aelem: /* $lex->[...] */
2488 sv = PAD_SVl((++items)->pad_offset);
2489 /* FALLTHROUGH */
2490
2491 do_AV_vivify_rv2av_aelem:
2492 case MDEREF_AV_vivify_rv2av_aelem: /* vivify, ->[...] */
2493 /* this is the OPpDEREF action normally found at the end of
2494 * ops like aelem, helem, rv2sv */
2495 sv = vivify_ref(sv, OPpDEREF_AV);
2496 /* FALLTHROUGH */
2497
2498 do_AV_rv2av_aelem:
2499 /* this is basically a copy of pp_rv2av when it just has the
2500 * sKR/1 flags */
2501 SvGETMAGIC(sv);
2502 if (LIKELY(SvROK(sv))) {
2503 if (UNLIKELY(SvAMAGIC(sv))) {
2504 sv = amagic_deref_call(sv, to_av_amg);
2505 }
2506 sv = SvRV(sv);
2507 if (UNLIKELY(SvTYPE(sv) != SVt_PVAV))
2508 DIE(aTHX_ "Not an ARRAY reference");
2509 }
2510 else if (SvTYPE(sv) != SVt_PVAV) {
2511 if (!isGV_with_GP(sv))
2512 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "an ARRAY", SVt_PVAV);
2513 sv = MUTABLE_SV(GvAVn((GV*)sv));
2514 }
2515 /* FALLTHROUGH */
2516
2517 do_AV_aelem:
2518 {
2519 /* retrieve the key; this may be either a lexical or package
2520 * var (whose index/ptr is stored as an item) or a signed
2521 * integer constant stored as an item.
2522 */
2523 SV *elemsv;
2524 IV elem = 0; /* to shut up stupid compiler warnings */
2525
2526
2527 assert(SvTYPE(sv) == SVt_PVAV);
2528
2529 switch (actions & MDEREF_INDEX_MASK) {
2530 case MDEREF_INDEX_none:
2531 goto finish;
2532 case MDEREF_INDEX_const:
2533 elem = (++items)->iv;
2534 break;
2535 case MDEREF_INDEX_padsv:
2536 elemsv = PAD_SVl((++items)->pad_offset);
2537 goto check_elem;
2538 case MDEREF_INDEX_gvsv:
2539 elemsv = UNOP_AUX_item_sv(++items);
2540 assert(isGV_with_GP(elemsv));
2541 elemsv = GvSVn((GV*)elemsv);
2542 check_elem:
2543 if (UNLIKELY(SvROK(elemsv) && !SvGAMAGIC(elemsv)
2544 && ckWARN(WARN_MISC)))
2545 Perl_warner(aTHX_ packWARN(WARN_MISC),
2546 "Use of reference \"%"SVf"\" as array index",
2547 SVfARG(elemsv));
2548 /* the only time that S_find_uninit_var() needs this
2549 * is to determine which index value triggered the
2550 * undef warning. So just update it here. Note that
2551 * since we don't save and restore this var (e.g. for
2552 * tie or overload execution), its value will be
2553 * meaningless apart from just here */
2554 PL_multideref_pc = items;
2555 elem = SvIV(elemsv);
2556 break;
2557 }
2558
2559
2560 /* this is basically a copy of pp_aelem with OPpDEREF skipped */
2561
2562 if (!(actions & MDEREF_FLAG_last)) {
2563 SV** svp = av_fetch((AV*)sv, elem, 1);
2564 if (!svp || ! (sv=*svp))
2565 DIE(aTHX_ PL_no_aelem, elem);
2566 break;
2567 }
2568
2569 if (PL_op->op_private &
2570 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
2571 {
2572 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
2573 sv = av_exists((AV*)sv, elem) ? &PL_sv_yes : &PL_sv_no;
2574 }
2575 else {
2576 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
2577 sv = av_delete((AV*)sv, elem, discard);
2578 if (discard)
2579 return NORMAL;
2580 if (!sv)
2581 sv = &PL_sv_undef;
2582 }
2583 }
2584 else {
2585 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2586 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
2587 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
2588 bool preeminent = TRUE;
2589 AV *const av = (AV*)sv;
2590 SV** svp;
2591
2592 if (UNLIKELY(localizing)) {
2593 MAGIC *mg;
2594 HV *stash;
2595
2596 /* If we can determine whether the element exist,
2597 * Try to preserve the existenceness of a tied array
2598 * element by using EXISTS and DELETE if possible.
2599 * Fallback to FETCH and STORE otherwise. */
2600 if (SvCANEXISTDELETE(av))
2601 preeminent = av_exists(av, elem);
2602 }
2603
2604 svp = av_fetch(av, elem, lval && !defer);
2605
2606 if (lval) {
2607 if (!svp || !(sv = *svp)) {
2608 IV len;
2609 if (!defer)
2610 DIE(aTHX_ PL_no_aelem, elem);
2611 len = av_tindex(av);
2612 sv = sv_2mortal(newSVavdefelem(av,
2613 /* Resolve a negative index now, unless it points
2614 * before the beginning of the array, in which
2615 * case record it for error reporting in
2616 * magic_setdefelem. */
2617 elem < 0 && len + elem >= 0
2618 ? len + elem : elem, 1));
2619 }
2620 else {
2621 if (UNLIKELY(localizing)) {
2622 if (preeminent) {
2623 save_aelem(av, elem, svp);
2624 sv = *svp; /* may have changed */
2625 }
2626 else
2627 SAVEADELETE(av, elem);
2628 }
2629 }
2630 }
2631 else {
2632 sv = (svp ? *svp : &PL_sv_undef);
2633 /* see note in pp_helem() */
2634 if (SvRMAGICAL(av) && SvGMAGICAL(sv))
2635 mg_get(sv);
2636 }
2637 }
2638
2639 }
2640 finish:
2641 {
2642 dSP;
2643 XPUSHs(sv);
2644 RETURN;
2645 }
2646 /* NOTREACHED */
2647
2648
2649
2650
2651 case MDEREF_HV_padhv_helem: /* $lex{...} */
2652 sv = PAD_SVl((++items)->pad_offset);
2653 goto do_HV_helem;
2654
2655 case MDEREF_HV_gvhv_helem: /* $pkg{...} */
2656 sv = UNOP_AUX_item_sv(++items);
2657 assert(isGV_with_GP(sv));
2658 sv = (SV*)GvHVn((GV*)sv);
2659 goto do_HV_helem;
2660
2661 case MDEREF_HV_pop_rv2hv_helem: /* expr->{...} */
2662 {
2663 dSP;
2664 sv = POPs;
2665 PUTBACK;
2666 goto do_HV_rv2hv_helem;
2667 }
2668
2669 case MDEREF_HV_gvsv_vivify_rv2hv_helem: /* $pkg->{...} */
2670 sv = UNOP_AUX_item_sv(++items);
2671 assert(isGV_with_GP(sv));
2672 sv = GvSVn((GV*)sv);
2673 goto do_HV_vivify_rv2hv_helem;
2674
2675 case MDEREF_HV_padsv_vivify_rv2hv_helem: /* $lex->{...} */
2676 sv = PAD_SVl((++items)->pad_offset);
2677 /* FALLTHROUGH */
2678
2679 do_HV_vivify_rv2hv_helem:
2680 case MDEREF_HV_vivify_rv2hv_helem: /* vivify, ->{...} */
2681 /* this is the OPpDEREF action normally found at the end of
2682 * ops like aelem, helem, rv2sv */
2683 sv = vivify_ref(sv, OPpDEREF_HV);
2684 /* FALLTHROUGH */
2685
2686 do_HV_rv2hv_helem:
2687 /* this is basically a copy of pp_rv2hv when it just has the
2688 * sKR/1 flags (and pp_rv2hv is aliased to pp_rv2av) */
2689
2690 SvGETMAGIC(sv);
2691 if (LIKELY(SvROK(sv))) {
2692 if (UNLIKELY(SvAMAGIC(sv))) {
2693 sv = amagic_deref_call(sv, to_hv_amg);
2694 }
2695 sv = SvRV(sv);
2696 if (UNLIKELY(SvTYPE(sv) != SVt_PVHV))
2697 DIE(aTHX_ "Not a HASH reference");
2698 }
2699 else if (SvTYPE(sv) != SVt_PVHV) {
2700 if (!isGV_with_GP(sv))
2701 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "a HASH", SVt_PVHV);
2702 sv = MUTABLE_SV(GvHVn((GV*)sv));
2703 }
2704 /* FALLTHROUGH */
2705
2706 do_HV_helem:
2707 {
2708 /* retrieve the key; this may be either a lexical / package
2709 * var or a string constant, whose index/ptr is stored as an
2710 * item
2711 */
2712 SV *keysv = NULL; /* to shut up stupid compiler warnings */
2713
2714 assert(SvTYPE(sv) == SVt_PVHV);
2715
2716 switch (actions & MDEREF_INDEX_MASK) {
2717 case MDEREF_INDEX_none:
2718 goto finish;
2719
2720 case MDEREF_INDEX_const:
2721 keysv = UNOP_AUX_item_sv(++items);
2722 break;
2723
2724 case MDEREF_INDEX_padsv:
2725 keysv = PAD_SVl((++items)->pad_offset);
2726 break;
2727
2728 case MDEREF_INDEX_gvsv:
2729 keysv = UNOP_AUX_item_sv(++items);
2730 keysv = GvSVn((GV*)keysv);
2731 break;
2732 }
2733
2734 /* see comment above about setting this var */
2735 PL_multideref_pc = items;
2736
2737
2738 /* ensure that candidate CONSTs have been HEKified */
2739 assert( ((actions & MDEREF_INDEX_MASK) != MDEREF_INDEX_const)
2740 || SvTYPE(keysv) >= SVt_PVMG
2741 || !SvOK(keysv)
2742 || SvROK(keysv)
2743 || SvIsCOW_shared_hash(keysv));
2744
2745 /* this is basically a copy of pp_helem with OPpDEREF skipped */
2746
2747 if (!(actions & MDEREF_FLAG_last)) {
2748 HE *he = hv_fetch_ent((HV*)sv, keysv, 1, 0);
2749 if (!he || !(sv=HeVAL(he)) || sv == &PL_sv_undef)
2750 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2751 break;
2752 }
2753
2754 if (PL_op->op_private &
2755 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
2756 {
2757 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
2758 sv = hv_exists_ent((HV*)sv, keysv, 0)
2759 ? &PL_sv_yes : &PL_sv_no;
2760 }
2761 else {
2762 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
2763 sv = hv_delete_ent((HV*)sv, keysv, discard, 0);
2764 if (discard)
2765 return NORMAL;
2766 if (!sv)
2767 sv = &PL_sv_undef;
2768 }
2769 }
2770 else {
2771 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2772 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
2773 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
2774 bool preeminent = TRUE;
2775 SV **svp;
2776 HV * const hv = (HV*)sv;
2777 HE* he;
2778
2779 if (UNLIKELY(localizing)) {
2780 MAGIC *mg;
2781 HV *stash;
2782
2783 /* If we can determine whether the element exist,
2784 * Try to preserve the existenceness of a tied hash
2785 * element by using EXISTS and DELETE if possible.
2786 * Fallback to FETCH and STORE otherwise. */
2787 if (SvCANEXISTDELETE(hv))
2788 preeminent = hv_exists_ent(hv, keysv, 0);
2789 }
2790
2791 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
2792 svp = he ? &HeVAL(he) : NULL;
2793
2794
2795 if (lval) {
2796 if (!svp || !(sv = *svp) || sv == &PL_sv_undef) {
2797 SV* lv;
2798 SV* key2;
2799 if (!defer)
2800 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2801 lv = sv_newmortal();
2802 sv_upgrade(lv, SVt_PVLV);
2803 LvTYPE(lv) = 'y';
2804 sv_magic(lv, key2 = newSVsv(keysv),
2805 PERL_MAGIC_defelem, NULL, 0);
2806 /* sv_magic() increments refcount */
2807 SvREFCNT_dec_NN(key2);
0ad694a7 2808 LvTARG(lv) = SvREFCNT_inc_simple_NN(hv);
fedf30e1
DM
2809 LvTARGLEN(lv) = 1;
2810 sv = lv;
2811 }
2812 else {
2813 if (localizing) {
2814 if (HvNAME_get(hv) && isGV(sv))
2815 save_gp(MUTABLE_GV(sv),
2816 !(PL_op->op_flags & OPf_SPECIAL));
2817 else if (preeminent) {
2818 save_helem_flags(hv, keysv, svp,
2819 (PL_op->op_flags & OPf_SPECIAL)
2820 ? 0 : SAVEf_SETMAGIC);
2821 sv = *svp; /* may have changed */
2822 }
2823 else
2824 SAVEHDELETE(hv, keysv);
2825 }
2826 }
2827 }
2828 else {
2829 sv = (svp && *svp ? *svp : &PL_sv_undef);
2830 /* see note in pp_helem() */
2831 if (SvRMAGICAL(hv) && SvGMAGICAL(sv))
2832 mg_get(sv);
2833 }
2834 }
2835 goto finish;
2836 }
2837
2838 } /* switch */
2839
2840 actions >>= MDEREF_SHIFT;
2841 } /* while */
2842 /* NOTREACHED */
2843}
2844
2845
a0d0e21e
LW
2846PP(pp_iter)
2847{
eb578fdb 2848 PERL_CONTEXT *cx;
7d6c2cef 2849 SV *oldsv;
1d7c1841 2850 SV **itersvp;
8a1f10dd 2851 SV *retsv;
a0d0e21e 2852
84f05d57
JH
2853 SV *sv;
2854 AV *av;
2855 IV ix;
2856 IV inc;
2857
4ebe6e95 2858 cx = CX_CUR();
1d7c1841 2859 itersvp = CxITERVAR(cx);
4b5c941e 2860 assert(itersvp);
a48ce6be
DM
2861
2862 switch (CxTYPE(cx)) {
17c91640 2863
b552b52c
DM
2864 case CXt_LOOP_LAZYSV: /* string increment */
2865 {
2866 SV* cur = cx->blk_loop.state_u.lazysv.cur;
2867 SV *end = cx->blk_loop.state_u.lazysv.end;
2868 /* If the maximum is !SvOK(), pp_enteriter substitutes PL_sv_no.
2869 It has SvPVX of "" and SvCUR of 0, which is what we want. */
2870 STRLEN maxlen = 0;
2871 const char *max = SvPV_const(end, maxlen);
5d9574c1 2872 if (UNLIKELY(SvNIOK(cur) || SvCUR(cur) > maxlen))
8a1f10dd 2873 goto retno;
b552b52c
DM
2874
2875 oldsv = *itersvp;
6d3ca00e
DM
2876 /* NB: on the first iteration, oldsv will have a ref count of at
2877 * least 2 (one extra from blk_loop.itersave), so the GV or pad
2878 * slot will get localised; on subsequent iterations the RC==1
2879 * optimisation may kick in and the SV will be reused. */
2880 if (oldsv && LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
b552b52c
DM
2881 /* safe to reuse old SV */
2882 sv_setsv(oldsv, cur);
a48ce6be 2883 }
b552b52c
DM
2884 else
2885 {
2886 /* we need a fresh SV every time so that loop body sees a
2887 * completely new SV for closures/references to work as
2888 * they used to */
2889 *itersvp = newSVsv(cur);
6d3ca00e 2890 SvREFCNT_dec(oldsv);
b552b52c
DM
2891 }
2892 if (strEQ(SvPVX_const(cur), max))
2893 sv_setiv(cur, 0); /* terminate next time */
2894 else
2895 sv_inc(cur);
2896 break;
2897 }
a48ce6be 2898
fcef60b4
DM
2899 case CXt_LOOP_LAZYIV: /* integer increment */
2900 {
2901 IV cur = cx->blk_loop.state_u.lazyiv.cur;
5d9574c1 2902 if (UNLIKELY(cur > cx->blk_loop.state_u.lazyiv.end))
8a1f10dd 2903 goto retno;
7f61b687 2904
fcef60b4 2905 oldsv = *itersvp;
6d3ca00e
DM
2906 /* see NB comment above */
2907 if (oldsv && LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
eaa5c2d6 2908 /* safe to reuse old SV */
47b96a1e
DM
2909
2910 if ( (SvFLAGS(oldsv) & (SVTYPEMASK|SVf_THINKFIRST|SVf_IVisUV))
2911 == SVt_IV)
2912 {
2913 /* Cheap SvIOK_only().
2914 * Assert that flags which SvIOK_only() would test or
2915 * clear can't be set, because we're SVt_IV */
2916 assert(!(SvFLAGS(oldsv) &
2917 (SVf_OOK|SVf_UTF8|(SVf_OK & ~(SVf_IOK|SVp_IOK)))));
2918 SvFLAGS(oldsv) |= (SVf_IOK|SVp_IOK);
2919 /* SvIV_set() where sv_any points to head */
2920 oldsv->sv_u.svu_iv = cur;
2921
2922 }
2923 else
2924 sv_setiv(oldsv, cur);
eaa5c2d6 2925 }
1c846c1f 2926 else
eaa5c2d6
GA
2927 {
2928 /* we need a fresh SV every time so that loop body sees a
2929 * completely new SV for closures/references to work as they
2930 * used to */
fcef60b4 2931 *itersvp = newSViv(cur);
6d3ca00e 2932 SvREFCNT_dec(oldsv);
eaa5c2d6 2933 }
a2309040 2934
5d9574c1 2935 if (UNLIKELY(cur == IV_MAX)) {
cdc1aa42
NC
2936 /* Handle end of range at IV_MAX */
2937 cx->blk_loop.state_u.lazyiv.end = IV_MIN;
2938 } else
2939 ++cx->blk_loop.state_u.lazyiv.cur;
a48ce6be 2940 break;
fcef60b4 2941 }
a48ce6be 2942
93661e56
DM
2943 case CXt_LOOP_LIST: /* for (1,2,3) */
2944
2945 assert(OPpITER_REVERSED == 2); /* so inc becomes -1 or 1 */
2946 inc = 1 - (PL_op->op_private & OPpITER_REVERSED);
2947 ix = (cx->blk_loop.state_u.stack.ix += inc);
2948 if (UNLIKELY(inc > 0
2949 ? ix > cx->blk_oldsp
2950 : ix <= cx->blk_loop.state_u.stack.basesp)
2951 )
8a1f10dd 2952 goto retno;
93661e56
DM
2953
2954 sv = PL_stack_base[ix];
2955 av = NULL;
2956 goto loop_ary_common;
2957
2958 case CXt_LOOP_ARY: /* for (@ary) */
2959
2960 av = cx->blk_loop.state_u.ary.ary;
2961 inc = 1 - (PL_op->op_private & OPpITER_REVERSED);
2962 ix = (cx->blk_loop.state_u.ary.ix += inc);
2963 if (UNLIKELY(inc > 0
2964 ? ix > AvFILL(av)
2965 : ix < 0)
2966 )
8a1f10dd 2967 goto retno;
de080daa 2968
9d1ee8e0 2969 if (UNLIKELY(SvRMAGICAL(av))) {
a8a20bb6
DM
2970 SV * const * const svp = av_fetch(av, ix, FALSE);
2971 sv = svp ? *svp : NULL;
2972 }
2973 else {
2974 sv = AvARRAY(av)[ix];
de080daa 2975 }
ef3e5ea9 2976
93661e56
DM
2977 loop_ary_common:
2978
d39c26a6
FC
2979 if (UNLIKELY(cx->cx_type & CXp_FOR_LVREF)) {
2980 SvSetMagicSV(*itersvp, sv);
2981 break;
2982 }
2983
5d9574c1
DM
2984 if (LIKELY(sv)) {
2985 if (UNLIKELY(SvIS_FREED(sv))) {
f38aa882
DM
2986 *itersvp = NULL;
2987 Perl_croak(aTHX_ "Use of freed value in iteration");
2988 }
60779a30 2989 if (SvPADTMP(sv)) {
8e079c2a 2990 sv = newSVsv(sv);
60779a30 2991 }
8e079c2a
FC
2992 else {
2993 SvTEMP_off(sv);
2994 SvREFCNT_inc_simple_void_NN(sv);
2995 }
de080daa 2996 }
93661e56 2997 else if (av) {
199f858d 2998 sv = newSVavdefelem(av, ix, 0);
de080daa 2999 }
a600f7e6
FC
3000 else
3001 sv = &PL_sv_undef;
a0d0e21e 3002
de080daa
DM
3003 oldsv = *itersvp;
3004 *itersvp = sv;
3005 SvREFCNT_dec(oldsv);
de080daa 3006 break;
a48ce6be
DM
3007
3008 default:
3009 DIE(aTHX_ "panic: pp_iter, type=%u", CxTYPE(cx));
3010 }
8a1f10dd
DM
3011
3012 retsv = &PL_sv_yes;
3013 if (0) {
3014 retno:
3015 retsv = &PL_sv_no;
3016 }
3017 /* pp_enteriter should have pre-extended the stack */
3018 assert(PL_stack_sp < PL_stack_max);
3019 *++PL_stack_sp =retsv;
3020
3021 return PL_op->op_next;
a0d0e21e
LW
3022}
3023
ef07e810
DM
3024/*
3025A description of how taint works in pattern matching and substitution.
3026
284167a5
SM
3027This is all conditional on NO_TAINT_SUPPORT not being defined. Under
3028NO_TAINT_SUPPORT, taint-related operations should become no-ops.
3029
4e19c54b 3030While the pattern is being assembled/concatenated and then compiled,
284167a5
SM
3031PL_tainted will get set (via TAINT_set) if any component of the pattern
3032is tainted, e.g. /.*$tainted/. At the end of pattern compilation,
3033the RXf_TAINTED flag is set on the pattern if PL_tainted is set (via
1738e041
DM
3034TAINT_get). It will also be set if any component of the pattern matches
3035based on locale-dependent behavior.
ef07e810 3036
0ab462a6
DM
3037When the pattern is copied, e.g. $r = qr/..../, the SV holding the ref to
3038the pattern is marked as tainted. This means that subsequent usage, such
284167a5
SM
3039as /x$r/, will set PL_tainted using TAINT_set, and thus RXf_TAINTED,
3040on the new pattern too.
ef07e810 3041
272d35c9 3042RXf_TAINTED_SEEN is used post-execution by the get magic code
ef07e810
DM
3043of $1 et al to indicate whether the returned value should be tainted.
3044It is the responsibility of the caller of the pattern (i.e. pp_match,
3045pp_subst etc) to set this flag for any other circumstances where $1 needs
3046to be tainted.
3047
3048The taint behaviour of pp_subst (and pp_substcont) is quite complex.
3049
3050There are three possible sources of taint
3051 * the source string
3052 * the pattern (both compile- and run-time, RXf_TAINTED / RXf_TAINTED_SEEN)
3053 * the replacement string (or expression under /e)
3054
3055There are four destinations of taint and they are affected by the sources
3056according to the rules below:
3057
3058 * the return value (not including /r):
3059 tainted by the source string and pattern, but only for the
3060 number-of-iterations case; boolean returns aren't tainted;
3061 * the modified string (or modified copy under /r):
3062 tainted by the source string, pattern, and replacement strings;
3063 * $1 et al:
3064 tainted by the pattern, and under 'use re "taint"', by the source
3065 string too;
3066 * PL_taint - i.e. whether subsequent code (e.g. in a /e block) is tainted:
3067 should always be unset before executing subsequent code.
3068
3069The overall action of pp_subst is:
3070
3071 * at the start, set bits in rxtainted indicating the taint status of
3072 the various sources.
3073
3074 * After each pattern execution, update the SUBST_TAINT_PAT bit in
3075 rxtainted if RXf_TAINTED_SEEN has been set, to indicate that the
3076 pattern has subsequently become tainted via locale ops.
3077
3078 * If control is being passed to pp_substcont to execute a /e block,
3079 save rxtainted in the CXt_SUBST block, for future use by
3080 pp_substcont.
3081
3082 * Whenever control is being returned to perl code (either by falling
3083 off the "end" of pp_subst/pp_substcont, or by entering a /e block),
3084 use the flag bits in rxtainted to make all the appropriate types of
0ab462a6
DM
3085 destination taint visible; e.g. set RXf_TAINTED_SEEN so that $1
3086 et al will appear tainted.
ef07e810
DM
3087
3088pp_match is just a simpler version of the above.
3089
3090*/
3091
a0d0e21e
LW
3092PP(pp_subst)
3093{
20b7effb 3094 dSP; dTARG;
eb578fdb 3095 PMOP *pm = cPMOP;
a0d0e21e 3096 PMOP *rpm = pm;
eb578fdb 3097 char *s;
a0d0e21e 3098 char *strend;
5c144d81 3099 const char *c;
a0d0e21e 3100 STRLEN clen;
3c6ef0a5
FC
3101 SSize_t iters = 0;
3102 SSize_t maxiters;
a0d0e21e 3103 bool once;
ef07e810
DM
3104 U8 rxtainted = 0; /* holds various SUBST_TAINT_* flag bits.
3105 See "how taint works" above */
a0d0e21e 3106 char *orig;
1ed74d04 3107 U8 r_flags;
eb578fdb 3108 REGEXP *rx = PM_GETRE(pm);
a0d0e21e
LW
3109 STRLEN len;
3110 int force_on_match = 0;
0bcc34c2 3111 const I32 oldsave = PL_savestack_ix;
792b2c16 3112 STRLEN slen;
26a74523 3113 bool doutf8 = FALSE; /* whether replacement is in utf8 */
db2c6cb3 3114#ifdef PERL_ANY_COW
106d9a13 3115 bool was_cow;
ed252734 3116#endif
a0714e2c 3117 SV *nsv = NULL;
b770e143 3118 /* known replacement string? */
eb578fdb 3119 SV *dstr = (pm->op_pmflags & PMf_CONST) ? POPs : NULL;
a0d0e21e 3120
f410a211
NC
3121 PERL_ASYNC_CHECK();
3122
533c011a 3123 if (PL_op->op_flags & OPf_STACKED)
a0d0e21e 3124 TARG = POPs;
6ffceeb7 3125 else if (ARGTARG)
59f00321 3126 GETTARGET;
a0d0e21e 3127 else {
54b9620d 3128 TARG = DEFSV;
a0d0e21e 3129 EXTEND(SP,1);
1c846c1f 3130 }
d9f424b2 3131
64534138 3132 SvGETMAGIC(TARG); /* must come before cow check */
db2c6cb3 3133#ifdef PERL_ANY_COW
106d9a13
DM
3134 /* note that a string might get converted to COW during matching */
3135 was_cow = cBOOL(SvIsCOW(TARG));
ed252734 3136#endif
d13a5d3b
TC
3137 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
3138#ifndef PERL_ANY_COW
3139 if (SvIsCOW(TARG))
3140 sv_force_normal_flags(TARG,0);
3141#endif
3142 if ((SvREADONLY(TARG)
3143 || ( ((SvTYPE(TARG) == SVt_PVGV && isGV_with_GP(TARG))
3144 || SvTYPE(TARG) > SVt_PVLV)
3145 && !(SvTYPE(TARG) == SVt_PVGV && SvFAKE(TARG)))))
3146 Perl_croak_no_modify();
3147 }
8ec5e241
NIS
3148 PUTBACK;
3149
6ac6605d
DM
3150 orig = SvPV_nomg(TARG, len);
3151 /* note we don't (yet) force the var into being a string; if we fail
92711104 3152 * to match, we leave as-is; on successful match however, we *will*
6ac6605d 3153 * coerce into a string, then repeat the match */
4499db73 3154 if (!SvPOKp(TARG) || SvTYPE(TARG) == SVt_PVGV || SvVOK(TARG))
a0d0e21e 3155 force_on_match = 1;
20be6587
DM
3156
3157 /* only replace once? */
3158 once = !(rpm->op_pmflags & PMf_GLOBAL);
3159
ef07e810 3160 /* See "how taint works" above */
284167a5 3161 if (TAINTING_get) {
20be6587
DM
3162 rxtainted = (
3163 (SvTAINTED(TARG) ? SUBST_TAINT_STR : 0)
284167a5 3164 | (RX_ISTAINTED(rx) ? SUBST_TAINT_PAT : 0)
20be6587
DM
3165 | ((pm->op_pmflags & PMf_RETAINT) ? SUBST_TAINT_RETAINT : 0)
3166 | ((once && !(rpm->op_pmflags & PMf_NONDESTRUCT))
3167 ? SUBST_TAINT_BOOLRET : 0));
3168 TAINT_NOT;
3169 }
a12c0f56 3170
a0d0e21e 3171 force_it:
6ac6605d
DM
3172 if (!pm || !orig)
3173 DIE(aTHX_ "panic: pp_subst, pm=%p, orig=%p", pm, orig);
a0d0e21e 3174
6ac6605d
DM
3175 strend = orig + len;
3176 slen = DO_UTF8(TARG) ? utf8_length((U8*)orig, (U8*)strend) : len;
792b2c16
JH
3177 maxiters = 2 * slen + 10; /* We can match twice at each
3178 position, once with zero-length,
3179 second time with non-zero. */
a0d0e21e 3180
794826f4
YO
3181 /* handle the empty pattern */
3182 if (!RX_PRELEN(rx) && PL_curpm && !ReANY(rx)->mother_re) {
3183 if (PL_curpm == PL_reg_curpm)
31775478 3184 Perl_croak(aTHX_ "Use of the empty pattern inside of "
794826f4 3185 "a regex code block is forbidden");
3280af22 3186 pm = PL_curpm;
aaa362c4 3187 rx = PM_GETRE(pm);
a0d0e21e 3188 }
6502e081 3189
6e240d0b 3190#ifdef PERL_SAWAMPERSAND
6502e081
DM
3191 r_flags = ( RX_NPARENS(rx)
3192 || PL_sawampersand
6502e081 3193 || (RX_EXTFLAGS(rx) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
5b0e71e9 3194 || (rpm->op_pmflags & PMf_KEEPCOPY)
6502e081
DM
3195 )
3196 ? REXEC_COPY_STR
3197 : 0;
6e240d0b
FC
3198#else
3199 r_flags = REXEC_COPY_STR;
3200#endif
7fba1cd6 3201
0395280b 3202 if (!CALLREGEXEC(rx, orig, strend, orig, 0, TARG, NULL, r_flags))
8b64c330 3203 {
5e79dfb9
DM
3204 SPAGAIN;
3205 PUSHs(rpm->op_pmflags & PMf_NONDESTRUCT ? TARG : &PL_sv_no);
3206 LEAVE_SCOPE(oldsave);
3207 RETURN;
3208 }
1754320d
FC
3209 PL_curpm = pm;
3210
71be2cbc 3211 /* known replacement string? */
f272994b 3212 if (dstr) {
8514a05a
JH
3213 /* replacement needing upgrading? */
3214 if (DO_UTF8(TARG) && !doutf8) {
db79b45b 3215 nsv = sv_newmortal();
4a176938 3216 SvSetSV(nsv, dstr);
8df0e7a2 3217 sv_utf8_upgrade(nsv);
5c144d81 3218 c = SvPV_const(nsv, clen);
4a176938
JH
3219 doutf8 = TRUE;
3220 }
3221 else {
5c144d81 3222 c = SvPV_const(dstr, clen);
4a176938 3223 doutf8 = DO_UTF8(dstr);
8514a05a 3224 }
bb933b9b
FC
3225
3226 if (SvTAINTED(dstr))
3227 rxtainted |= SUBST_TAINT_REPL;
f272994b
A
3228 }
3229 else {
6136c704 3230 c = NULL;
f272994b
A
3231 doutf8 = FALSE;
3232 }
3233
71be2cbc 3234 /* can do inplace substitution? */
ed252734 3235 if (c
db2c6cb3 3236#ifdef PERL_ANY_COW
106d9a13 3237 && !was_cow
ed252734 3238#endif
fbfb1899 3239 && (I32)clen <= RX_MINLENRET(rx)
9cefd268
FC
3240 && ( once
3241 || !(r_flags & REXEC_COPY_STR)
3242 || (!SvGMAGICAL(dstr) && !(RX_EXTFLAGS(rx) & RXf_EVAL_SEEN))
3243 )
dbc200c5 3244 && !(RX_EXTFLAGS(rx) & RXf_NO_INPLACE_SUBST)
8ca8a454
NC
3245 && (!doutf8 || SvUTF8(TARG))
3246 && !(rpm->op_pmflags & PMf_NONDESTRUCT))
8b030b38 3247 {
ec911639 3248
db2c6cb3 3249#ifdef PERL_ANY_COW
106d9a13 3250 /* string might have got converted to COW since we set was_cow */
ed252734 3251 if (SvIsCOW(TARG)) {
f7a8268c 3252 if (!force_on_match)
ed252734 3253 goto have_a_cow;
f7a8268c 3254 assert(SvVOK(TARG));
ed252734
NC
3255 }
3256#endif
71be2cbc 3257 if (force_on_match) {
6ac6605d
DM
3258 /* redo the first match, this time with the orig var
3259 * forced into being a string */
71be2cbc 3260 force_on_match = 0;
6ac6605d 3261 orig = SvPV_force_nomg(TARG, len);
71be2cbc
PP
3262 goto force_it;
3263 }
39b40493 3264
71be2cbc 3265 if (once) {
c67ab8f2 3266 char *d, *m;
20be6587
DM
3267 if (RX_MATCH_TAINTED(rx)) /* run time pattern taint, eg locale */
3268 rxtainted |= SUBST_TAINT_PAT;
07bc277f
NC
3269 m = orig + RX_OFFS(rx)[0].start;
3270 d = orig + RX_OFFS(rx)[0].end;
71be2cbc
PP
3271 s = orig;
3272 if (m - s > strend - d) { /* faster to shorten from end */
2ec7214c 3273 I32 i;
71be2cbc
PP
3274 if (clen) {
3275 Copy(c, m, clen, char);
3276 m += clen;
a0d0e21e 3277 }
71be2cbc
PP
3278 i = strend - d;
3279 if (i > 0) {
3280 Move(d, m, i, char);
3281 m += i;
a0d0e21e 3282 }
71be2cbc
PP
3283 *m = '\0';
3284 SvCUR_set(TARG, m - s);
3285 }
2ec7214c
DM
3286 else { /* faster from front */
3287 I32 i = m - s;
71be2cbc 3288 d -= clen;
2ec7214c
DM
3289 if (i > 0)
3290 Move(s, d - i, i, char);
71be2cbc 3291 sv_chop(TARG, d-i);
71be2cbc 3292 if (clen)
c947cd8d 3293 Copy(c, d, clen, char);
71be2cbc 3294 }
8ec5e241 3295 SPAGAIN;
8ca8a454 3296 PUSHs(&PL_sv_yes);
71be2cbc
PP
3297 }
3298 else {
c67ab8f2 3299 char *d, *m;
0395280b 3300 d = s = RX_OFFS(rx)[0].start + orig;
71be2cbc 3301 do {
2b25edcf 3302 I32 i;
5d9574c1 3303 if (UNLIKELY(iters++ > maxiters))
cea2e8a9 3304 DIE(aTHX_ "Substitution loop");
5d9574c1 3305 if (UNLIKELY(RX_MATCH_TAINTED(rx))) /* run time pattern taint, eg locale */
20be6587 3306 rxtainted |= SUBST_TAINT_PAT;
07bc277f 3307 m = RX_OFFS(rx)[0].start + orig;
155aba94 3308 if ((i = m - s)) {
71be2cbc
PP
3309 if (s != d)
3310 Move(s, d, i, char);
3311 d += i;
a0d0e21e 3312 }
71be2cbc
PP
3313 if (clen) {
3314 Copy(c, d, clen, char);
3315 d += clen;
3316 }
07bc277f 3317 s = RX_OFFS(rx)[0].end + orig;
7ce41e5c
FC
3318 } while (CALLREGEXEC(rx, s, strend, orig,
3319 s == m, /* don't match same null twice */
f722798b 3320 TARG, NULL,
d5e7783a 3321 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
71be2cbc 3322 if (s != d) {
2b25edcf 3323 I32 i = strend - s;
aa07b2f6 3324 SvCUR_set(TARG, d - SvPVX_const(TARG) + i);
71be2cbc 3325 Move(s, d, i+1, char); /* include the NUL */
a0d0e21e 3326 }
8ec5e241 3327 SPAGAIN;
3c6ef0a5 3328 mPUSHi(iters);
a0d0e21e
LW
3329 }
3330 }
ff6e92e8 3331 else {
1754320d 3332 bool first;
c67ab8f2 3333 char *m;
1754320d 3334 SV *repl;
a0d0e21e 3335 if (force_on_match) {
6ac6605d
DM
3336 /* redo the first match, this time with the orig var
3337 * forced into being a string */
a0d0e21e 3338 force_on_match = 0;
0c1438a1
NC
3339 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
3340 /* I feel that it should be possible to avoid this mortal copy
3341 given that the code below copies into a new destination.
3342 However, I suspect it isn't worth the complexity of
3343 unravelling the C<goto force_it> for the small number of
3344 cases where it would be viable to drop into the copy code. */
3345 TARG = sv_2mortal(newSVsv(TARG));
3346 }
6ac6605d 3347 orig = SvPV_force_nomg(TARG, len);
a0d0e21e
LW
3348 goto force_it;
3349 }
db2c6cb3 3350#ifdef PERL_ANY_COW
ed252734
NC
3351 have_a_cow:
3352#endif
20be6587
DM
3353 if (RX_MATCH_TAINTED(rx)) /* run time pattern taint, eg locale */
3354 rxtainted |= SUBST_TAINT_PAT;
1754320d 3355 repl = dstr;
0395280b
DM
3356 s = RX_OFFS(rx)[0].start + orig;
3357 dstr = newSVpvn_flags(orig, s-orig,
3358 SVs_TEMP | (DO_UTF8(TARG) ? SVf_UTF8 : 0));
a0d0e21e 3359 if (!c) {
eb578fdb 3360 PERL_CONTEXT *cx;
8ec5e241 3361 SPAGAIN;
0395280b 3362 m = orig;
20be6587
DM
3363 /* note that a whole bunch of local vars are saved here for
3364 * use by pp_substcont: here's a list of them in case you're
3365 * searching for places in this sub that uses a particular var:
3366 * iters maxiters r_flags oldsave rxtainted orig dstr targ
3367 * s m strend rx once */
490576d1 3368 CX_PUSHSUBST(cx);
20e98b0f 3369 RETURNOP(cPMOP->op_pmreplrootu.op_pmreplroot);
a0d0e21e 3370 }
1754320d 3371 first = TRUE;
a0d0e21e 3372 do {
5d9574c1 3373 if (UNLIKELY(iters++ > maxiters))
cea2e8a9 3374 DIE(aTHX_ "Substitution loop");
5d9574c1 3375 if (UNLIKELY(RX_MATCH_TAINTED(rx)))
20be6587 3376 rxtainted |= SUBST_TAINT_PAT;
07bc277f 3377 if (RX_MATCH_COPIED(rx) && RX_SUBBEG(rx) != orig) {
c67ab8f2
DM
3378 char *old_s = s;
3379 char *old_orig = orig;
6502e081 3380 assert(RX_SUBOFFSET(rx) == 0);
c67ab8f2 3381
07bc277f 3382 orig = RX_SUBBEG(rx);
c67ab8f2
DM
3383 s = orig + (old_s - old_orig);
3384 strend = s + (strend - old_s);
a0d0e21e 3385 }
07bc277f 3386 m = RX_OFFS(rx)[0].start + orig;
64534138 3387 sv_catpvn_nomg_maybeutf8(dstr, s, m - s, DO_UTF8(TARG));
07bc277f 3388 s = RX_OFFS(rx)[0].end + orig;
1754320d
FC
3389 if (first) {
3390 /* replacement already stringified */
3391 if (clen)
64534138 3392 sv_catpvn_nomg_maybeutf8(dstr, c, clen, doutf8);
1754320d
FC
3393 first = FALSE;
3394 }
3395 else {
8df0e7a2 3396 sv_catsv(dstr, repl);
5d9574c1 3397 if (UNLIKELY(SvTAINTED(repl)))
bb933b9b 3398 rxtainted |= SUBST_TAINT_REPL;
1754320d 3399 }
a0d0e21e
LW
3400 if (once)
3401 break;
ff27773b
KW
3402 } while (CALLREGEXEC(rx, s, strend, orig,
3403 s == m, /* Yields minend of 0 or 1 */
d5e7783a
DM
3404 TARG, NULL,
3405 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
aba224f7 3406 assert(strend >= s);
64534138 3407 sv_catpvn_nomg_maybeutf8(dstr, s, strend - s, DO_UTF8(TARG));
748a9306 3408
8ca8a454
NC
3409 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
3410 /* From here on down we're using the copy, and leaving the original
3411 untouched. */
3412 TARG = dstr;
3413 SPAGAIN;
3414 PUSHs(dstr);
3415 } else {
db2c6cb3 3416#ifdef PERL_ANY_COW
8ca8a454
NC
3417 /* The match may make the string COW. If so, brilliant, because
3418 that's just saved us one malloc, copy and free - the regexp has
3419 donated the old buffer, and we malloc an entirely new one, rather
3420 than the regexp malloc()ing a buffer and copying our original,
3421 only for us to throw it away here during the substitution. */
3422 if (SvIsCOW(TARG)) {
3423 sv_force_normal_flags(TARG, SV_COW_DROP_PV);
3424 } else
ed252734 3425#endif
8ca8a454
NC
3426 {
3427 SvPV_free(TARG);
3428 }
3429 SvPV_set(TARG, SvPVX(dstr));
3430 SvCUR_set(TARG, SvCUR(dstr));
3431 SvLEN_set(TARG, SvLEN(dstr));
64534138 3432 SvFLAGS(TARG) |= SvUTF8(dstr);
8ca8a454 3433 SvPV_set(dstr, NULL);
748a9306 3434
8ca8a454 3435 SPAGAIN;
3c6ef0a5 3436 mPUSHi(iters);
8ca8a454
NC
3437 }
3438 }
3439
3440 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
3441 (void)SvPOK_only_UTF8(TARG);
a0d0e21e 3442 }
20be6587 3443
ef07e810 3444 /* See "how taint works" above */
284167a5 3445 if (TAINTING_get) {
20be6587
DM
3446 if ((rxtainted & SUBST_TAINT_PAT) ||
3447 ((rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_RETAINT)) ==
3448 (SUBST_TAINT_STR|SUBST_TAINT_RETAINT))
3449 )
3450 (RX_MATCH_TAINTED_on(rx)); /* taint $1 et al */
3451
3452 if (!(rxtainted & SUBST_TAINT_BOOLRET)
3453 && (rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT))
3454 )
3455 SvTAINTED_on(TOPs); /* taint return value */
3456 else
3457 SvTAINTED_off(TOPs); /* may have got tainted earlier */
3458
3459 /* needed for mg_set below */
284167a5
SM
3460 TAINT_set(
3461 cBOOL(rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT|SUBST_TAINT_REPL))
3462 );
20be6587
DM
3463 SvTAINT(TARG);
3464 }
3465 SvSETMAGIC(TARG); /* PL_tainted must be correctly set for this mg_set */
3466 TAINT_NOT;
f1a76097
DM
3467 LEAVE_SCOPE(oldsave);
3468 RETURN;
a0d0e21e
LW
3469}
3470
3471PP(pp_grepwhile)
3472{
20b7effb 3473 dSP;
a0d0e21e
LW
3474
3475 if (SvTRUEx(POPs))
3280af22
NIS
3476 PL_stack_base[PL_markstack_ptr[-1]++] = PL_stack_base[*PL_markstack_ptr];
3477 ++*PL_markstack_ptr;
b2a2a901 3478 FREETMPS;
d343c3ef 3479 LEAVE_with_name("grep_item"); /* exit inner scope */
a0d0e21e
LW
3480
3481 /* All done yet? */
5d9574c1 3482 if (UNLIKELY(PL_stack_base + *PL_markstack_ptr > SP)) {
a0d0e21e 3483 I32 items;
1c23e2bd 3484 const U8 gimme = GIMME_V;
a0d0e21e 3485
d343c3ef 3486 LEAVE_with_name("grep"); /* exit outer scope */
a0d0e21e 3487 (void)POPMARK; /* pop src */
3280af22 3488 items = --*PL_markstack_ptr - PL_markstack_ptr[-1];
a0d0e21e 3489 (void)POPMARK; /* pop dst */
3280af22 3490 SP = PL_stack_base + POPMARK; /* pop original mark */
54310121 3491 if (gimme == G_SCALAR) {
7cc47870
RGS
3492 dTARGET;
3493 XPUSHi(items);
a0d0e21e 3494 }
54310121
PP
3495 else if (gimme == G_ARRAY)
3496 SP += items;
a0d0e21e
LW
3497 RETURN;
3498 }
3499 else {
3500 SV *src;
3501
d343c3ef 3502 ENTER_with_name("grep_item"); /* enter inner scope */
1d7c1841 3503 SAVEVPTR(PL_curpm);
a0d0e21e 3504
6cae08a8 3505 src = PL_stack_base[TOPMARK];
60779a30 3506 if (SvPADTMP(src)) {
6cae08a8 3507 src = PL_stack_base[TOPMARK] = sv_mortalcopy(src);
a0ed822e
FC
3508 PL_tmps_floor++;
3509 }
a0d0e21e 3510 SvTEMP_off(src);
ffd49c98 3511 DEFSV_set(src);
a0d0e21e
LW
3512
3513 RETURNOP(cLOGOP->op_other);
3514 }
3515}
3516
799da9d7 3517/* leave_adjust_stacks():
f7a874b8 3518 *
e02ce34b
DM
3519 * Process a scope's return args (in the range from_sp+1 .. PL_stack_sp),
3520 * positioning them at to_sp+1 onwards, and do the equivalent of a
3521 * FREEMPS and TAINT_NOT.
3522 *
f7a874b8
DM
3523 * Not intended to be called in void context.
3524 *
799da9d7
DM
3525 * When leaving a sub, eval, do{} or other scope, the things that need
3526 * doing to process the return args are:
f7a874b8 3527 * * in scalar context, only return the last arg (or PL_sv_undef if none);
799da9d7
DM
3528 * * for the types of return that return copies of their args (such
3529 * as rvalue sub return), make a mortal copy of every return arg,
3530 * except where we can optimise the copy away without it being
3531 * semantically visible;
3532 * * make sure that the arg isn't prematurely freed; in the case of an
3533 * arg not copied, this may involve mortalising it. For example, in
f7a874b8
DM
3534 * C<sub f { my $x = ...; $x }>, $x would be freed when we do
3535 * CX_LEAVE_SCOPE(cx) unless it's protected or copied.
3536 *
799da9d7
DM
3537 * What condition to use when deciding whether to pass the arg through
3538 * or make a copy, is determined by the 'pass' arg; its valid values are:
3539 * 0: rvalue sub/eval exit
3540 * 1: other rvalue scope exit
3541 * 2: :lvalue sub exit in rvalue context
3542 * 3: :lvalue sub exit in lvalue context and other lvalue scope exits
3543 *
f7a874b8 3544 * There is a big issue with doing a FREETMPS. We would like to free any
799da9d7 3545 * temps created by the last statement which the sub executed, rather than
f7a874b8
DM
3546 * leaving them for the caller. In a situation where a sub call isn't
3547 * soon followed by a nextstate (e.g. nested recursive calls, a la
3548 * fibonacci()), temps can accumulate, causing memory and performance
3549 * issues.
3550 *
3551 * On the other hand, we don't want to free any TEMPs which are keeping
799da9d7
DM
3552 * alive any return args that we skipped copying; nor do we wish to undo
3553 * any mortalising done here.
f7a874b8
DM
3554 *
3555 * The solution is to split the temps stack frame into two, with a cut
3556 * point delineating the two halves. We arrange that by the end of this
3557 * function, all the temps stack frame entries we wish to keep are in the
799da9d7 3558 * range PL_tmps_floor+1.. tmps_base-1, while the ones to free now are in
f7a874b8
DM
3559 * the range tmps_base .. PL_tmps_ix. During the course of this
3560 * function, tmps_base starts off as PL_tmps_floor+1, then increases
3561 * whenever we find or create a temp that we know should be kept. In
3562 * general the stuff above tmps_base is undecided until we reach the end,
3563 * and we may need a sort stage for that.
3564 *
3565 * To determine whether a TEMP is keeping a return arg alive, every
3566 * arg that is kept rather than copied and which has the SvTEMP flag
3567 * set, has the flag temporarily unset, to mark it. At the end we scan
799da9d7 3568 * the temps stack frame above the cut for entries without SvTEMP and
f7a874b8 3569 * keep them, while turning SvTEMP on again. Note that if we die before
799da9d7 3570 * the SvTEMPs flags are set again, its safe: at worst, subsequent use of
f7a874b8
DM
3571 * those SVs may be slightly less efficient.
3572 *
3573 * In practice various optimisations for some common cases mean we can
3574 * avoid most of the scanning and swapping about with the temps stack.
3575 */
3576
799da9d7 3577void
1c23e2bd 3578Perl_leave_adjust_stacks(pTHX_ SV **from_sp, SV **to_sp, U8 gimme, int pass)
a0d0e21e 3579{
263e0548 3580 dVAR;
20b7effb 3581 dSP;
f7a874b8
DM
3582 SSize_t tmps_base; /* lowest index into tmps stack that needs freeing now */
3583 SSize_t nargs;
3584
799da9d7
DM
3585 PERL_ARGS_ASSERT_LEAVE_ADJUST_STACKS;
3586
f7a874b8
DM
3587 TAINT_NOT;
3588
3589 if (gimme == G_ARRAY) {
e02ce34b
DM
3590 nargs = SP - from_sp;
3591 from_sp++;
f7a874b8
DM
3592 }
3593 else {
3594 assert(gimme == G_SCALAR);
e02ce34b 3595 if (UNLIKELY(from_sp >= SP)) {
f7a874b8 3596 /* no return args */
e02ce34b 3597 assert(from_sp == SP);
f7a874b8
DM
3598 EXTEND(SP, 1);
3599 *++SP = &PL_sv_undef;
e02ce34b 3600 to_sp = SP;
f7a874b8
DM
3601 nargs = 0;
3602 }
3603 else {
3604 from_sp = SP;
3605 nargs = 1;
3606 }
3607 }
3608
3609 /* common code for G_SCALAR and G_ARRAY */
3610
3611 tmps_base = PL_tmps_floor + 1;
3612
3613 assert(nargs >= 0);
3614 if (nargs) {
3615 /* pointer version of tmps_base. Not safe across temp stack
3616 * reallocs. */
3617 SV **tmps_basep;
3618
3619 EXTEND_MORTAL(nargs); /* one big extend for worst-case scenario */
3620 tmps_basep = PL_tmps_stack + tmps_base;
f7a874b8
DM
3621
3622 /* process each return arg */
3623
3624 do {
3625 SV *sv = *from_sp++;
3626
3627 assert(PL_tmps_ix + nargs < PL_tmps_max);
3645bb38
DM
3628#ifdef DEBUGGING
3629 /* PADTMPs with container set magic shouldn't appear in the
3630 * wild. This assert is more important for pp_leavesublv(),
3631 * but by testing for it here, we're more likely to catch
3632 * bad cases (what with :lvalue subs not being widely
3633 * deployed). The two issues are that for something like
3634 * sub :lvalue { $tied{foo} }
3635 * or
3636 * sub :lvalue { substr($foo,1,2) }
3637 * pp_leavesublv() will croak if the sub returns a PADTMP,
3638 * and currently functions like pp_substr() return a mortal
3639 * rather than using their PADTMP when returning a PVLV.
3640 * This is because the PVLV will hold a ref to $foo,
3641 * so $foo would get delayed in being freed while
3642 * the PADTMP SV remained in the PAD.
3643 * So if this assert fails it means either:
3644 * 1) there is pp code similar to pp_substr that is