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[perl5.git] / pp_hot.c
CommitLineData
a0d0e21e
LW
1/* pp_hot.c
2 *
1129b882
NC
3 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4 * 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
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;
1c23e2bd 1252 U8 gimme;
a68090fe
DM
1253 /* PL_delaymagic is restored by JUMPENV_POP on dieing, so we
1254 * only need to save locally, not on the save stack */
1255 U16 old_delaymagic = PL_delaymagic;
ebc643ce
DM
1256#ifdef DEBUGGING
1257 bool fake = 0;
1258#endif
5637b936 1259
3280af22 1260 PL_delaymagic = DM_DELAY; /* catch simultaneous items */
a0d0e21e
LW
1261
1262 /* If there's a common identifier on both sides we have to take
1263 * special care that assigning the identifier on the left doesn't
1264 * clobber a value on the right that's used later in the list.
1265 */
acdea6f0 1266
beb08a1e
TC
1267 /* at least 2 LH and RH elements, or commonality isn't an issue */
1268 if (firstlelem < lastlelem && firstrelem < lastrelem) {
5c1db569
TC
1269 for (relem = firstrelem+1; relem <= lastrelem; relem++) {
1270 if (SvGMAGICAL(*relem))
1271 goto do_scan;
1272 }
beb08a1e
TC
1273 for (lelem = firstlelem; lelem <= lastlelem; lelem++) {
1274 if (*lelem && SvSMAGICAL(*lelem))
1275 goto do_scan;
a5f48505 1276 }
beb08a1e
TC
1277 if ( PL_op->op_private & (OPpASSIGN_COMMON_SCALAR|OPpASSIGN_COMMON_RC1) ) {
1278 if (PL_op->op_private & OPpASSIGN_COMMON_RC1) {
1279 /* skip the scan if all scalars have a ref count of 1 */
1280 for (lelem = firstlelem; lelem <= lastlelem; lelem++) {
8b0c3377 1281 SV *sv = *lelem;
beb08a1e
TC
1282 if (!sv || SvREFCNT(sv) == 1)
1283 continue;
1284 if (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVAV)
1285 goto do_scan;
1286 break;
1287 }
1288 }
1289 else {
1290 do_scan:
1291 S_aassign_copy_common(aTHX_
1292 firstlelem, lastlelem, firstrelem, lastrelem
ebc643ce 1293#ifdef DEBUGGING
beb08a1e 1294 , fake
ebc643ce 1295#endif
beb08a1e
TC
1296 );
1297 }
a5f48505 1298 }
a0d0e21e 1299 }
ebc643ce
DM
1300#ifdef DEBUGGING
1301 else {
1302 /* on debugging builds, do the scan even if we've concluded we
1303 * don't need to, then panic if we find commonality. Note that the
1304 * scanner assumes at least 2 elements */
1305 if (firstlelem < lastlelem && firstrelem < lastrelem) {
1306 fake = 1;
1307 goto do_scan;
1308 }
1309 }
1310#endif
a0d0e21e 1311
a5f48505 1312 gimme = GIMME_V;
a0d0e21e
LW
1313 relem = firstrelem;
1314 lelem = firstlelem;
10c8fecd 1315
8b0c3377
DM
1316 if (relem > lastrelem)
1317 goto no_relems;
1318
1319 /* first lelem loop while there are still relems */
5d9574c1 1320 while (LIKELY(lelem <= lastlelem)) {
bdaf10a5 1321 bool alias = FALSE;
8b0c3377
DM
1322 SV *lsv = *lelem++;
1323
1324 assert(relem <= lastrelem);
1325 if (UNLIKELY(!lsv)) {
bdaf10a5 1326 alias = TRUE;
8b0c3377
DM
1327 lsv = *lelem++;
1328 ASSUME(SvTYPE(lsv) == SVt_PVAV);
bdaf10a5 1329 }
a5f48505 1330
8b0c3377
DM
1331 switch (SvTYPE(lsv)) {
1332 case SVt_PVAV: {
1333 SV **svp;
1334 SSize_t i;
1335 SSize_t tmps_base;
1336 SSize_t nelems = lastrelem - relem + 1;
b09ed995 1337 AV *ary = MUTABLE_AV(lsv);
8b0c3377
DM
1338
1339 /* Assigning to an aggregate is tricky. First there is the
1340 * issue of commonality, e.g. @a = ($a[0]). Since the
1341 * stack isn't refcounted, clearing @a prior to storing
1342 * elements will free $a[0]. Similarly with
1343 * sub FETCH { $status[$_[1]] } @status = @tied[0,1];
1344 *
1345 * The way to avoid these issues is to make the copy of each
1346 * SV (and we normally store a *copy* in the array) *before*
1347 * clearing the array. But this has a problem in that
1348 * if the code croaks during copying, the not-yet-stored copies
1349 * could leak. One way to avoid this is to make all the copies
1350 * mortal, but that's quite expensive.
1351 *
1352 * The current solution to these issues is to use a chunk
1353 * of the tmps stack as a temporary refcounted-stack. SVs
1354 * will be put on there during processing to avoid leaks,
1355 * but will be removed again before the end of this block,
1356 * so free_tmps() is never normally called. Also, the
1357 * sv_refcnt of the SVs doesn't have to be manipulated, since
1358 * the ownership of 1 reference count is transferred directly
1359 * from the tmps stack to the AV when the SV is stored.
1360 *
1361 * We disarm slots in the temps stack by storing PL_sv_undef
1362 * there: it doesn't matter if that SV's refcount is
1363 * repeatedly decremented during a croak. But usually this is
1364 * only an interim measure. By the end of this code block
1365 * we try where possible to not leave any PL_sv_undef's on the
1366 * tmps stack e.g. by shuffling newer entries down.
1367 *
1368 * There is one case where we don't copy: non-magical
1369 * SvTEMP(sv)'s with a ref count of 1. The only owner of these
1370 * is on the tmps stack, so its safe to directly steal the SV
1371 * rather than copying. This is common in things like function
1372 * returns, map etc, which all return a list of such SVs.
1373 *
1374 * Note however something like @a = (f())[0,0], where there is
1375 * a danger of the same SV being shared: this avoided because
1376 * when the SV is stored as $a[0], its ref count gets bumped,
1377 * so the RC==1 test fails and the second element is copied
1378 * instead.
1379 *
1380 * We also use one slot in the tmps stack to hold an extra
1381 * ref to the array, to ensure it doesn't get prematurely
1382 * freed. Again, this is removed before the end of this block.
1383 *
1384 * Note that OPpASSIGN_COMMON_AGG is used to flag a possible
1385 * @a = ($a[0]) case, but the current implementation uses the
1386 * same algorithm regardless, so ignores that flag. (It *is*
1387 * used in the hash branch below, however).
1388 */
1389
1390 /* Reserve slots for ary, plus the elems we're about to copy,
1391 * then protect ary and temporarily void the remaining slots
1392 * with &PL_sv_undef */
1393 EXTEND_MORTAL(nelems + 1);
1394 PL_tmps_stack[++PL_tmps_ix] = SvREFCNT_inc_simple_NN(ary);
1395 tmps_base = PL_tmps_ix + 1;
1396 for (i = 0; i < nelems; i++)
1397 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
1398 PL_tmps_ix += nelems;
1399
1400 /* Make a copy of each RHS elem and save on the tmps_stack
1401 * (or pass through where we can optimise away the copy) */
1402
1403 if (UNLIKELY(alias)) {
1404 U32 lval = (gimme == G_ARRAY)
1405 ? (PL_op->op_flags & OPf_MOD || LVRET) : 0;
a5f48505 1406 for (svp = relem; svp <= lastrelem; svp++) {
8b0c3377
DM
1407 SV *rsv = *svp;
1408
1409 SvGETMAGIC(rsv);
1410 if (!SvROK(rsv))
1411 DIE(aTHX_ "Assigned value is not a reference");
1412 if (SvTYPE(SvRV(rsv)) > SVt_PVLV)
1413 /* diag_listed_as: Assigned value is not %s reference */
1414 DIE(aTHX_
1415 "Assigned value is not a SCALAR reference");
1416 if (lval)
1417 *svp = rsv = sv_mortalcopy(rsv);
1418 /* XXX else check for weak refs? */
1419 rsv = SvREFCNT_inc_NN(SvRV(rsv));
1420 assert(tmps_base <= PL_tmps_max);
1421 PL_tmps_stack[tmps_base++] = rsv;
a5f48505 1422 }
a5f48505 1423 }
8b0c3377
DM
1424 else {
1425 for (svp = relem; svp <= lastrelem; svp++) {
1426 SV *rsv = *svp;
a5f48505 1427
8b0c3377
DM
1428 if (SvTEMP(rsv) && !SvGMAGICAL(rsv) && SvREFCNT(rsv) == 1) {
1429 /* can skip the copy */
1430 SvREFCNT_inc_simple_void_NN(rsv);
1431 SvTEMP_off(rsv);
1432 }
a5f48505 1433 else {
8b0c3377
DM
1434 SV *nsv;
1435 /* do get before newSV, in case it dies and leaks */
1436 SvGETMAGIC(rsv);
1437 nsv = newSV(0);
8c1e192f
DM
1438 /* see comment in S_aassign_copy_common about
1439 * SV_NOSTEAL */
8b0c3377
DM
1440 sv_setsv_flags(nsv, rsv,
1441 (SV_DO_COW_SVSETSV|SV_NOSTEAL));
1442 rsv = *svp = nsv;
a5f48505 1443 }
8b0c3377
DM
1444
1445 assert(tmps_base <= PL_tmps_max);
1446 PL_tmps_stack[tmps_base++] = rsv;
1447 }
1448 }
1449
1450 if (SvRMAGICAL(ary) || AvFILLp(ary) >= 0) /* may be non-empty */
1451 av_clear(ary);
1452
1453 /* store in the array, the SVs that are in the tmps stack */
1454
1455 tmps_base -= nelems;
1456
1457 if (SvRMAGICAL(ary) || SvREADONLY(ary) || !AvREAL(ary)) {
1458 /* for arrays we can't cheat with, use the official API */
1459 av_extend(ary, nelems - 1);
1460 for (i = 0; i < nelems; i++) {
1461 SV **svp = &(PL_tmps_stack[tmps_base + i]);
1462 SV *rsv = *svp;
1463 /* A tied store won't take ownership of rsv, so keep
1464 * the 1 refcnt on the tmps stack; otherwise disarm
1465 * the tmps stack entry */
1466 if (av_store(ary, i, rsv))
1467 *svp = &PL_sv_undef;
1468 /* av_store() may have added set magic to rsv */;
1469 SvSETMAGIC(rsv);
1470 }
1471 /* disarm ary refcount: see comments below about leak */
1472 PL_tmps_stack[tmps_base - 1] = &PL_sv_undef;
1473 }
1474 else {
1475 /* directly access/set the guts of the AV */
1476 SSize_t fill = nelems - 1;
1477 if (fill > AvMAX(ary))
1478 av_extend_guts(ary, fill, &AvMAX(ary), &AvALLOC(ary),
1479 &AvARRAY(ary));
1480 AvFILLp(ary) = fill;
1481 Copy(&(PL_tmps_stack[tmps_base]), AvARRAY(ary), nelems, SV*);
1482 /* Quietly remove all the SVs from the tmps stack slots,
1483 * since ary has now taken ownership of the refcnt.
1484 * Also remove ary: which will now leak if we die before
1485 * the SvREFCNT_dec_NN(ary) below */
1486 if (UNLIKELY(PL_tmps_ix >= tmps_base + nelems))
1487 Move(&PL_tmps_stack[tmps_base + nelems],
1488 &PL_tmps_stack[tmps_base - 1],
1489 PL_tmps_ix - (tmps_base + nelems) + 1,
1490 SV*);
1491 PL_tmps_ix -= (nelems + 1);
1492 }
1493
5d9574c1 1494 if (UNLIKELY(PL_delaymagic & DM_ARRAY_ISA))
8b0c3377 1495 /* its assumed @ISA set magic can't die and leak ary */
ad64d0ec 1496 SvSETMAGIC(MUTABLE_SV(ary));
8b0c3377
DM
1497 SvREFCNT_dec_NN(ary);
1498
1499 relem = lastrelem + 1;
1500 goto no_relems;
a5f48505
DM
1501 }
1502
10c8fecd 1503 case SVt_PVHV: { /* normal hash */
8b0c3377
DM
1504
1505 SV **svp;
1506 bool dirty_tmps;
1507 SSize_t i;
1508 SSize_t tmps_base;
1509 SSize_t nelems = lastrelem - relem + 1;
b09ed995 1510 HV *hash = MUTABLE_HV(lsv);
8b0c3377
DM
1511
1512 if (UNLIKELY(nelems & 1)) {
1513 do_oddball(lastrelem, relem);
1514 /* we have firstlelem to reuse, it's not needed any more */
1515 *++lastrelem = &PL_sv_undef;
1516 nelems++;
1517 }
1518
1519 /* See the SVt_PVAV branch above for a long description of
1520 * how the following all works. The main difference for hashes
1521 * is that we treat keys and values separately (and have
1522 * separate loops for them): as for arrays, values are always
1523 * copied (except for the SvTEMP optimisation), since they
1524 * need to be stored in the hash; while keys are only
1525 * processed where they might get prematurely freed or
1526 * whatever. */
1527
1528 /* tmps stack slots:
1529 * * reserve a slot for the hash keepalive;
1530 * * reserve slots for the hash values we're about to copy;
1531 * * preallocate for the keys we'll possibly copy or refcount bump
1532 * later;
1533 * then protect hash and temporarily void the remaining
1534 * value slots with &PL_sv_undef */
1535 EXTEND_MORTAL(nelems + 1);
1536
1537 /* convert to number of key/value pairs */
1538 nelems >>= 1;
1539
1540 PL_tmps_stack[++PL_tmps_ix] = SvREFCNT_inc_simple_NN(hash);
1541 tmps_base = PL_tmps_ix + 1;
1542 for (i = 0; i < nelems; i++)
1543 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
1544 PL_tmps_ix += nelems;
1545
1546 /* Make a copy of each RHS hash value and save on the tmps_stack
1547 * (or pass through where we can optimise away the copy) */
1548
1549 for (svp = relem + 1; svp <= lastrelem; svp += 2) {
1550 SV *rsv = *svp;
1551
1552 if (SvTEMP(rsv) && !SvGMAGICAL(rsv) && SvREFCNT(rsv) == 1) {
1553 /* can skip the copy */
1554 SvREFCNT_inc_simple_void_NN(rsv);
1555 SvTEMP_off(rsv);
1556 }
1557 else {
1558 SV *nsv;
1559 /* do get before newSV, in case it dies and leaks */
1560 SvGETMAGIC(rsv);
1561 nsv = newSV(0);
1562 /* see comment in S_aassign_copy_common about
1563 * SV_NOSTEAL */
1564 sv_setsv_flags(nsv, rsv,
1565 (SV_DO_COW_SVSETSV|SV_NOSTEAL));
1566 rsv = *svp = nsv;
1c4ea384
RZ
1567 }
1568
8b0c3377
DM
1569 assert(tmps_base <= PL_tmps_max);
1570 PL_tmps_stack[tmps_base++] = rsv;
1571 }
1572 tmps_base -= nelems;
a5f48505 1573
a5f48505 1574
8b0c3377
DM
1575 /* possibly protect keys */
1576
1577 if (UNLIKELY(gimme == G_ARRAY)) {
1578 /* handle e.g.
1579 * @a = ((%h = ($$r, 1)), $r = "x");
1580 * $_++ for %h = (1,2,3,4);
1581 */
1582 EXTEND_MORTAL(nelems);
1583 for (svp = relem; svp <= lastrelem; svp += 2)
1584 *svp = sv_mortalcopy_flags(*svp,
1585 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
1586 }
1587 else if (PL_op->op_private & OPpASSIGN_COMMON_AGG) {
1588 /* for possible commonality, e.g.
1589 * %h = ($h{a},1)
1590 * avoid premature freeing RHS keys by mortalising
1591 * them.
1592 * For a magic element, make a copy so that its magic is
1593 * called *before* the hash is emptied (which may affect
1594 * a tied value for example).
1595 * In theory we should check for magic keys in all
1596 * cases, not just under OPpASSIGN_COMMON_AGG, but in
1597 * practice, !OPpASSIGN_COMMON_AGG implies only
1598 * constants or padtmps on the RHS.
1599 */
1600 EXTEND_MORTAL(nelems);
1601 for (svp = relem; svp <= lastrelem; svp += 2) {
1602 SV *rsv = *svp;
1603 if (UNLIKELY(SvGMAGICAL(rsv))) {
1604 SSize_t n;
a5f48505
DM
1605 *svp = sv_mortalcopy_flags(*svp,
1606 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
8b0c3377
DM
1607 /* allow other branch to continue pushing
1608 * onto tmps stack without checking each time */
1609 n = (lastrelem - relem) >> 1;
1610 EXTEND_MORTAL(n);
a5f48505 1611 }
8b0c3377
DM
1612 else
1613 PL_tmps_stack[++PL_tmps_ix] =
1614 SvREFCNT_inc_simple_NN(rsv);
a5f48505 1615 }
8b0c3377 1616 }
a5f48505 1617
8b0c3377
DM
1618 if (SvRMAGICAL(hash) || HvUSEDKEYS(hash))
1619 hv_clear(hash);
a5f48505 1620
8b0c3377
DM
1621 /* now assign the keys and values to the hash */
1622
1623 dirty_tmps = FALSE;
1624
1625 if (UNLIKELY(gimme == G_ARRAY)) {
1626 /* @a = (%h = (...)) etc */
1627 SV **svp;
1628 SV **topelem = relem;
1629
1630 for (i = 0, svp = relem; svp <= lastrelem; i++, svp++) {
1631 SV *key = *svp++;
1632 SV *val = *svp;
1633 /* remove duplicates from list we return */
1634 if (!hv_exists_ent(hash, key, 0)) {
1635 /* copy key back: possibly to an earlier
1636 * stack location if we encountered dups earlier,
1637 * The values will be updated later
1638 */
1639 *topelem = key;
1640 topelem += 2;
632b9d6f 1641 }
8b0c3377
DM
1642 /* A tied store won't take ownership of val, so keep
1643 * the 1 refcnt on the tmps stack; otherwise disarm
1644 * the tmps stack entry */
1645 if (hv_store_ent(hash, key, val, 0))
1646 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
1647 else
1648 dirty_tmps = TRUE;
1649 /* hv_store_ent() may have added set magic to val */;
1650 SvSETMAGIC(val);
1651 }
1652 if (topelem < svp) {
1c4ea384
RZ
1653 /* at this point we have removed the duplicate key/value
1654 * pairs from the stack, but the remaining values may be
1655 * wrong; i.e. with (a 1 a 2 b 3) on the stack we've removed
1656 * the (a 2), but the stack now probably contains
1657 * (a <freed> b 3), because { hv_save(a,1); hv_save(a,2) }
1658 * obliterates the earlier key. So refresh all values. */
8b0c3377
DM
1659 lastrelem = topelem - 1;
1660 while (relem < lastrelem) {
1c4ea384
RZ
1661 HE *he;
1662 he = hv_fetch_ent(hash, *relem++, 0, 0);
1663 *relem++ = (he ? HeVAL(he) : &PL_sv_undef);
1664 }
1665 }
8b0c3377
DM
1666 }
1667 else {
1668 SV **svp;
1669 for (i = 0, svp = relem; svp <= lastrelem; i++, svp++) {
1670 SV *key = *svp++;
1671 SV *val = *svp;
1672 if (hv_store_ent(hash, key, val, 0))
1673 PL_tmps_stack[tmps_base + i] = &PL_sv_undef;
1674 else
1675 dirty_tmps = TRUE;
1676 /* hv_store_ent() may have added set magic to val */;
1677 SvSETMAGIC(val);
1678 }
1679 }
1680
1681 if (dirty_tmps) {
1682 /* there are still some 'live' recounts on the tmps stack
1683 * - usually caused by storing into a tied hash. So let
1684 * free_tmps() do the proper but slow job later.
1685 * Just disarm hash refcount: see comments below about leak
1686 */
1687 PL_tmps_stack[tmps_base - 1] = &PL_sv_undef;
1688 }
1689 else {
1690 /* Quietly remove all the SVs from the tmps stack slots,
1691 * since hash has now taken ownership of the refcnt.
1692 * Also remove hash: which will now leak if we die before
1693 * the SvREFCNT_dec_NN(hash) below */
1694 if (UNLIKELY(PL_tmps_ix >= tmps_base + nelems))
1695 Move(&PL_tmps_stack[tmps_base + nelems],
1696 &PL_tmps_stack[tmps_base - 1],
1697 PL_tmps_ix - (tmps_base + nelems) + 1,
1698 SV*);
1699 PL_tmps_ix -= (nelems + 1);
1700 }
1701
1702 SvREFCNT_dec_NN(hash);
1703
1704 relem = lastrelem + 1;
1705 goto no_relems;
1706 }
1707
a0d0e21e 1708 default:
8b0c3377
DM
1709 if (!SvIMMORTAL(lsv)) {
1710 if (UNLIKELY(
1711 SvTEMP(lsv) && !SvSMAGICAL(lsv) && SvREFCNT(lsv) == 1 &&
1712 (!isGV_with_GP(lsv) || SvFAKE(lsv)) && ckWARN(WARN_MISC)
1713 ))
1714 Perl_warner(aTHX_
1715 packWARN(WARN_MISC),
1716 "Useless assignment to a temporary"
1717 );
1718 sv_setsv(lsv, *relem);
1719 *relem = lsv;
1720 SvSETMAGIC(lsv);
1721 }
1722 if (++relem > lastrelem)
1723 goto no_relems;
a0d0e21e 1724 break;
8b0c3377
DM
1725 } /* switch */
1726 } /* while */
1727
1728
1729 no_relems:
1730
1731 /* simplified lelem loop for when there are no relems left */
1732 while (LIKELY(lelem <= lastlelem)) {
1733 SV *lsv = *lelem++;
1734 if (UNLIKELY(!lsv)) {
1735 lsv = *lelem++;
1736 ASSUME(SvTYPE(lsv) == SVt_PVAV);
a0d0e21e 1737 }
8b0c3377
DM
1738
1739 switch (SvTYPE(lsv)) {
1740 case SVt_PVAV:
b09ed995
DM
1741 if (SvRMAGICAL(lsv) || AvFILLp((SV*)lsv) >= 0) {
1742 av_clear((AV*)lsv);
8b0c3377 1743 if (UNLIKELY(PL_delaymagic & DM_ARRAY_ISA))
b09ed995 1744 SvSETMAGIC(lsv);
8b0c3377
DM
1745 }
1746 break;
1747
1748 case SVt_PVHV:
b09ed995
DM
1749 if (SvRMAGICAL(lsv) || HvUSEDKEYS((HV*)lsv))
1750 hv_clear((HV*)lsv);
8b0c3377
DM
1751 break;
1752
1753 default:
1754 if (!SvIMMORTAL(lsv)) {
1755 sv_setsv(lsv, &PL_sv_undef);
1756 SvSETMAGIC(lsv);
b09ed995 1757 *relem++ = lsv;
8b0c3377
DM
1758 }
1759 break;
1760 } /* switch */
1761 } /* while */
1762
5d9574c1 1763 if (UNLIKELY(PL_delaymagic & ~DM_DELAY)) {
985213f2 1764 /* Will be used to set PL_tainting below */
dfff4baf
BF
1765 Uid_t tmp_uid = PerlProc_getuid();
1766 Uid_t tmp_euid = PerlProc_geteuid();
1767 Gid_t tmp_gid = PerlProc_getgid();
1768 Gid_t tmp_egid = PerlProc_getegid();
985213f2 1769
b469f1e0 1770 /* XXX $> et al currently silently ignore failures */
3280af22 1771 if (PL_delaymagic & DM_UID) {
a0d0e21e 1772#ifdef HAS_SETRESUID
b469f1e0
JH
1773 PERL_UNUSED_RESULT(
1774 setresuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
1775 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1,
1776 (Uid_t)-1));
56febc5e
AD
1777#else
1778# ifdef HAS_SETREUID
b469f1e0
JH
1779 PERL_UNUSED_RESULT(
1780 setreuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
1781 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1));
56febc5e
AD
1782# else
1783# ifdef HAS_SETRUID
b28d0864 1784 if ((PL_delaymagic & DM_UID) == DM_RUID) {
b469f1e0 1785 PERL_UNUSED_RESULT(setruid(PL_delaymagic_uid));
b28d0864 1786 PL_delaymagic &= ~DM_RUID;
a0d0e21e 1787 }
56febc5e
AD
1788# endif /* HAS_SETRUID */
1789# ifdef HAS_SETEUID
b28d0864 1790 if ((PL_delaymagic & DM_UID) == DM_EUID) {
b469f1e0 1791 PERL_UNUSED_RESULT(seteuid(PL_delaymagic_euid));
b28d0864 1792 PL_delaymagic &= ~DM_EUID;
a0d0e21e 1793 }
56febc5e 1794# endif /* HAS_SETEUID */
b28d0864 1795 if (PL_delaymagic & DM_UID) {
985213f2 1796 if (PL_delaymagic_uid != PL_delaymagic_euid)
cea2e8a9 1797 DIE(aTHX_ "No setreuid available");
b469f1e0 1798 PERL_UNUSED_RESULT(PerlProc_setuid(PL_delaymagic_uid));
a0d0e21e 1799 }
56febc5e
AD
1800# endif /* HAS_SETREUID */
1801#endif /* HAS_SETRESUID */
04783dc7 1802
985213f2
AB
1803 tmp_uid = PerlProc_getuid();
1804 tmp_euid = PerlProc_geteuid();
a0d0e21e 1805 }
b469f1e0 1806 /* XXX $> et al currently silently ignore failures */
3280af22 1807 if (PL_delaymagic & DM_GID) {
a0d0e21e 1808#ifdef HAS_SETRESGID
b469f1e0
JH
1809 PERL_UNUSED_RESULT(
1810 setresgid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
1811 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1,
1812 (Gid_t)-1));
56febc5e
AD
1813#else
1814# ifdef HAS_SETREGID
b469f1e0
JH
1815 PERL_UNUSED_RESULT(
1816 setregid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
1817 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1));
56febc5e
AD
1818# else
1819# ifdef HAS_SETRGID
b28d0864 1820 if ((PL_delaymagic & DM_GID) == DM_RGID) {
b469f1e0 1821 PERL_UNUSED_RESULT(setrgid(PL_delaymagic_gid));
b28d0864 1822 PL_delaymagic &= ~DM_RGID;
a0d0e21e 1823 }
56febc5e
AD
1824# endif /* HAS_SETRGID */
1825# ifdef HAS_SETEGID
b28d0864 1826 if ((PL_delaymagic & DM_GID) == DM_EGID) {
b469f1e0 1827 PERL_UNUSED_RESULT(setegid(PL_delaymagic_egid));
b28d0864 1828 PL_delaymagic &= ~DM_EGID;
a0d0e21e 1829 }
56febc5e 1830# endif /* HAS_SETEGID */
b28d0864 1831 if (PL_delaymagic & DM_GID) {
985213f2 1832 if (PL_delaymagic_gid != PL_delaymagic_egid)
cea2e8a9 1833 DIE(aTHX_ "No setregid available");
b469f1e0 1834 PERL_UNUSED_RESULT(PerlProc_setgid(PL_delaymagic_gid));
a0d0e21e 1835 }
56febc5e
AD
1836# endif /* HAS_SETREGID */
1837#endif /* HAS_SETRESGID */
04783dc7 1838
985213f2
AB
1839 tmp_gid = PerlProc_getgid();
1840 tmp_egid = PerlProc_getegid();
a0d0e21e 1841 }
284167a5 1842 TAINTING_set( TAINTING_get | (tmp_uid && (tmp_euid != tmp_uid || tmp_egid != tmp_gid)) );
9a9b5ec9
DM
1843#ifdef NO_TAINT_SUPPORT
1844 PERL_UNUSED_VAR(tmp_uid);
1845 PERL_UNUSED_VAR(tmp_euid);
1846 PERL_UNUSED_VAR(tmp_gid);
1847 PERL_UNUSED_VAR(tmp_egid);
1848#endif
a0d0e21e 1849 }
a68090fe 1850 PL_delaymagic = old_delaymagic;
54310121 1851
54310121
PP
1852 if (gimme == G_VOID)
1853 SP = firstrelem - 1;
1854 else if (gimme == G_SCALAR) {
1855 dTARGET;
1856 SP = firstrelem;
b09ed995 1857 EXTEND(SP,1);
8b0c3377 1858 SETi(firstlelem - firstrelem);
54310121 1859 }
b09ed995
DM
1860 else
1861 SP = relem - 1;
08aeb9f7 1862
54310121 1863 RETURN;
a0d0e21e
LW
1864}
1865
8782bef2
GB
1866PP(pp_qr)
1867{
20b7effb 1868 dSP;
eb578fdb 1869 PMOP * const pm = cPMOP;
fe578d7f 1870 REGEXP * rx = PM_GETRE(pm);
10599a69 1871 SV * const pkg = rx ? CALLREG_PACKAGE(rx) : NULL;
c4420975 1872 SV * const rv = sv_newmortal();
d63c20f2
DM
1873 CV **cvp;
1874 CV *cv;
288b8c02
NC
1875
1876 SvUPGRADE(rv, SVt_IV);
c2123ae3
NC
1877 /* For a subroutine describing itself as "This is a hacky workaround" I'm
1878 loathe to use it here, but it seems to be the right fix. Or close.
1879 The key part appears to be that it's essential for pp_qr to return a new
1880 object (SV), which implies that there needs to be an effective way to
1881 generate a new SV from the existing SV that is pre-compiled in the
1882 optree. */
1883 SvRV_set(rv, MUTABLE_SV(reg_temp_copy(NULL, rx)));
288b8c02
NC
1884 SvROK_on(rv);
1885
8d919b0a 1886 cvp = &( ReANY((REGEXP *)SvRV(rv))->qr_anoncv);
5d9574c1 1887 if (UNLIKELY((cv = *cvp) && CvCLONE(*cvp))) {
d63c20f2 1888 *cvp = cv_clone(cv);
fc2b2dca 1889 SvREFCNT_dec_NN(cv);
d63c20f2
DM
1890 }
1891
288b8c02 1892 if (pkg) {
f815daf2 1893 HV *const stash = gv_stashsv(pkg, GV_ADD);
fc2b2dca 1894 SvREFCNT_dec_NN(pkg);
288b8c02
NC
1895 (void)sv_bless(rv, stash);
1896 }
1897
5d9574c1 1898 if (UNLIKELY(RX_ISTAINTED(rx))) {
e08e52cf 1899 SvTAINTED_on(rv);
9274aefd
DM
1900 SvTAINTED_on(SvRV(rv));
1901 }
c8c13c22 1902 XPUSHs(rv);
1903 RETURN;
8782bef2
GB
1904}
1905
a0d0e21e
LW
1906PP(pp_match)
1907{
20b7effb 1908 dSP; dTARG;
eb578fdb 1909 PMOP *pm = cPMOP;
d65afb4b 1910 PMOP *dynpm = pm;
eb578fdb 1911 const char *s;
5c144d81 1912 const char *strend;
99a90e59 1913 SSize_t curpos = 0; /* initial pos() or current $+[0] */
a0d0e21e 1914 I32 global;
7fadf4a7 1915 U8 r_flags = 0;
5c144d81 1916 const char *truebase; /* Start of string */
eb578fdb 1917 REGEXP *rx = PM_GETRE(pm);
b3eb6a9b 1918 bool rxtainted;
1c23e2bd 1919 const U8 gimme = GIMME_V;
a0d0e21e 1920 STRLEN len;
a3b680e6 1921 const I32 oldsave = PL_savestack_ix;
e60df1fa 1922 I32 had_zerolen = 0;
b1422d62 1923 MAGIC *mg = NULL;
a0d0e21e 1924
533c011a 1925 if (PL_op->op_flags & OPf_STACKED)
a0d0e21e 1926 TARG = POPs;
6ffceeb7 1927 else if (ARGTARG)
59f00321 1928 GETTARGET;
a0d0e21e 1929 else {
54b9620d 1930 TARG = DEFSV;
a0d0e21e
LW
1931 EXTEND(SP,1);
1932 }
d9f424b2 1933
c277df42 1934 PUTBACK; /* EVAL blocks need stack_sp. */
69dc4b30
FC
1935 /* Skip get-magic if this is a qr// clone, because regcomp has
1936 already done it. */
f1d31338 1937 truebase = ReANY(rx)->mother_re
69dc4b30
FC
1938 ? SvPV_nomg_const(TARG, len)
1939 : SvPV_const(TARG, len);
f1d31338 1940 if (!truebase)
2269b42e 1941 DIE(aTHX_ "panic: pp_match");
f1d31338 1942 strend = truebase + len;
284167a5
SM
1943 rxtainted = (RX_ISTAINTED(rx) ||
1944 (TAINT_get && (pm->op_pmflags & PMf_RETAINT)));
9212bbba 1945 TAINT_NOT;
a0d0e21e 1946
6c864ec2 1947 /* We need to know this in case we fail out early - pos() must be reset */
de0df3c0
MH
1948 global = dynpm->op_pmflags & PMf_GLOBAL;
1949
d65afb4b 1950 /* PMdf_USED is set after a ?? matches once */
c737faaf
YO
1951 if (
1952#ifdef USE_ITHREADS
1953 SvREADONLY(PL_regex_pad[pm->op_pmoffset])
1954#else
1955 pm->op_pmflags & PMf_USED
1956#endif
1957 ) {
e5dc5375 1958 DEBUG_r(PerlIO_printf(Perl_debug_log, "?? already matched once"));
de0df3c0 1959 goto nope;
a0d0e21e
LW
1960 }
1961
7e313637
FC
1962 /* empty pattern special-cased to use last successful pattern if
1963 possible, except for qr// */
794826f4
YO
1964 if (!ReANY(rx)->mother_re && !RX_PRELEN(rx) && PL_curpm) {
1965 if (PL_curpm == PL_reg_curpm)
31775478 1966 Perl_croak(aTHX_ "Use of the empty pattern inside of "
794826f4 1967 "a regex code block is forbidden");
3280af22 1968 pm = PL_curpm;
aaa362c4 1969 rx = PM_GETRE(pm);
a0d0e21e 1970 }
d65afb4b 1971
389ecb56 1972 if (RX_MINLEN(rx) >= 0 && (STRLEN)RX_MINLEN(rx) > len) {
75d43e96
FC
1973 DEBUG_r(PerlIO_printf(Perl_debug_log, "String shorter than min possible regex match (%"
1974 UVuf" < %"IVdf")\n",
1975 (UV)len, (IV)RX_MINLEN(rx)));
de0df3c0 1976 goto nope;
e5dc5375 1977 }
c277df42 1978
8ef97b0e 1979 /* get pos() if //g */
de0df3c0 1980 if (global) {
b1422d62 1981 mg = mg_find_mglob(TARG);
8ef97b0e 1982 if (mg && mg->mg_len >= 0) {
25fdce4a 1983 curpos = MgBYTEPOS(mg, TARG, truebase, len);
8ef97b0e
DM
1984 /* last time pos() was set, it was zero-length match */
1985 if (mg->mg_flags & MGf_MINMATCH)
1986 had_zerolen = 1;
1987 }
a0d0e21e 1988 }
8ef97b0e 1989
6e240d0b 1990#ifdef PERL_SAWAMPERSAND
a41aa44d 1991 if ( RX_NPARENS(rx)
6502e081 1992 || PL_sawampersand
6502e081 1993 || (RX_EXTFLAGS(rx) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
5b0e71e9 1994 || (dynpm->op_pmflags & PMf_KEEPCOPY)
6e240d0b
FC
1995 )
1996#endif
1997 {
6502e081
DM
1998 r_flags |= (REXEC_COPY_STR|REXEC_COPY_SKIP_PRE);
1999 /* in @a =~ /(.)/g, we iterate multiple times, but copy the buffer
2000 * only on the first iteration. Therefore we need to copy $' as well
2001 * as $&, to make the rest of the string available for captures in
2002 * subsequent iterations */
2003 if (! (global && gimme == G_ARRAY))
2004 r_flags |= REXEC_COPY_SKIP_POST;
2005 };
5b0e71e9
DM
2006#ifdef PERL_SAWAMPERSAND
2007 if (dynpm->op_pmflags & PMf_KEEPCOPY)
2008 /* handle KEEPCOPY in pmop but not rx, eg $r=qr/a/; /$r/p */
2009 r_flags &= ~(REXEC_COPY_SKIP_PRE|REXEC_COPY_SKIP_POST);
2010#endif
22e551b9 2011
f1d31338
DM
2012 s = truebase;
2013
d7be1480 2014 play_it_again:
985afbc1 2015 if (global)
03c83e26 2016 s = truebase + curpos;
f722798b 2017
77da2310 2018 if (!CALLREGEXEC(rx, (char*)s, (char *)strend, (char*)truebase,
03c83e26 2019 had_zerolen, TARG, NULL, r_flags))
03b6c93d 2020 goto nope;
77da2310
NC
2021
2022 PL_curpm = pm;
985afbc1 2023 if (dynpm->op_pmflags & PMf_ONCE)
c737faaf 2024#ifdef USE_ITHREADS
77da2310 2025 SvREADONLY_on(PL_regex_pad[dynpm->op_pmoffset]);
c737faaf 2026#else
77da2310 2027 dynpm->op_pmflags |= PMf_USED;
c737faaf 2028#endif
a0d0e21e 2029
72311751
GS
2030 if (rxtainted)
2031 RX_MATCH_TAINTED_on(rx);
2032 TAINT_IF(RX_MATCH_TAINTED(rx));
35c2ccc3
DM
2033
2034 /* update pos */
2035
2036 if (global && (gimme != G_ARRAY || (dynpm->op_pmflags & PMf_CONTINUE))) {
b1422d62 2037 if (!mg)
35c2ccc3 2038 mg = sv_magicext_mglob(TARG);
25fdce4a 2039 MgBYTEPOS_set(mg, TARG, truebase, RX_OFFS(rx)[0].end);
adf51885
DM
2040 if (RX_ZERO_LEN(rx))
2041 mg->mg_flags |= MGf_MINMATCH;
2042 else
2043 mg->mg_flags &= ~MGf_MINMATCH;
35c2ccc3
DM
2044 }
2045
bf9dff51
DM
2046 if ((!RX_NPARENS(rx) && !global) || gimme != G_ARRAY) {
2047 LEAVE_SCOPE(oldsave);
2048 RETPUSHYES;
2049 }
2050
88ab22af
DM
2051 /* push captures on stack */
2052
bf9dff51 2053 {
07bc277f 2054 const I32 nparens = RX_NPARENS(rx);
a3b680e6 2055 I32 i = (global && !nparens) ? 1 : 0;
a0d0e21e 2056
c277df42 2057 SPAGAIN; /* EVAL blocks could move the stack. */
ffc61ed2
JH
2058 EXTEND(SP, nparens + i);
2059 EXTEND_MORTAL(nparens + i);
2060 for (i = !i; i <= nparens; i++) {
a0d0e21e 2061 PUSHs(sv_newmortal());
5d9574c1
DM
2062 if (LIKELY((RX_OFFS(rx)[i].start != -1)
2063 && RX_OFFS(rx)[i].end != -1 ))
2064 {
07bc277f 2065 const I32 len = RX_OFFS(rx)[i].end - RX_OFFS(rx)[i].start;
f1d31338 2066 const char * const s = RX_OFFS(rx)[i].start + truebase;
5d9574c1
DM
2067 if (UNLIKELY(RX_OFFS(rx)[i].end < 0 || RX_OFFS(rx)[i].start < 0
2068 || len < 0 || len > strend - s))
5637ef5b
NC
2069 DIE(aTHX_ "panic: pp_match start/end pointers, i=%ld, "
2070 "start=%ld, end=%ld, s=%p, strend=%p, len=%"UVuf,
2071 (long) i, (long) RX_OFFS(rx)[i].start,
2072 (long)RX_OFFS(rx)[i].end, s, strend, (UV) len);
a0d0e21e 2073 sv_setpvn(*SP, s, len);
cce850e4 2074 if (DO_UTF8(TARG) && is_utf8_string((U8*)s, len))
a197cbdd 2075 SvUTF8_on(*SP);
a0d0e21e
LW
2076 }
2077 }
2078 if (global) {
0e0b3e82 2079 curpos = (UV)RX_OFFS(rx)[0].end;
03c83e26 2080 had_zerolen = RX_ZERO_LEN(rx);
c277df42 2081 PUTBACK; /* EVAL blocks may use stack */
cf93c79d 2082 r_flags |= REXEC_IGNOREPOS | REXEC_NOT_FIRST;
a0d0e21e
LW
2083 goto play_it_again;
2084 }
4633a7c4 2085 LEAVE_SCOPE(oldsave);
a0d0e21e
LW
2086 RETURN;
2087 }
e5964223 2088 NOT_REACHED; /* NOTREACHED */
a0d0e21e 2089
7b52d656 2090 nope:
d65afb4b 2091 if (global && !(dynpm->op_pmflags & PMf_CONTINUE)) {
b1422d62
DM
2092 if (!mg)
2093 mg = mg_find_mglob(TARG);
2094 if (mg)
2095 mg->mg_len = -1;
a0d0e21e 2096 }
4633a7c4 2097 LEAVE_SCOPE(oldsave);
a0d0e21e
LW
2098 if (gimme == G_ARRAY)
2099 RETURN;
2100 RETPUSHNO;
2101}
2102
2103OP *
864dbfa3 2104Perl_do_readline(pTHX)
a0d0e21e 2105{
20b7effb 2106 dSP; dTARGETSTACKED;
eb578fdb 2107 SV *sv;
a0d0e21e
LW
2108 STRLEN tmplen = 0;
2109 STRLEN offset;
760ac839 2110 PerlIO *fp;
eb578fdb
KW
2111 IO * const io = GvIO(PL_last_in_gv);
2112 const I32 type = PL_op->op_type;
1c23e2bd 2113 const U8 gimme = GIMME_V;
a0d0e21e 2114
6136c704 2115 if (io) {
50db69d8 2116 const MAGIC *const mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar);
6136c704 2117 if (mg) {
3e0cb5de 2118 Perl_tied_method(aTHX_ SV_CONST(READLINE), SP, MUTABLE_SV(io), mg, gimme, 0);
6136c704 2119 if (gimme == G_SCALAR) {
50db69d8
NC
2120 SPAGAIN;
2121 SvSetSV_nosteal(TARG, TOPs);
2122 SETTARG;
6136c704 2123 }
50db69d8 2124 return NORMAL;
0b7c7b4f 2125 }
e79b0511 2126 }
4608196e 2127 fp = NULL;
a0d0e21e
LW
2128 if (io) {
2129 fp = IoIFP(io);
2130 if (!fp) {
2131 if (IoFLAGS(io) & IOf_ARGV) {
2132 if (IoFLAGS(io) & IOf_START) {
a0d0e21e 2133 IoLINES(io) = 0;
b9f2b683 2134 if (av_tindex(GvAVn(PL_last_in_gv)) < 0) {
1d7c1841 2135 IoFLAGS(io) &= ~IOf_START;
d5eb9a46 2136 do_open6(PL_last_in_gv, "-", 1, NULL, NULL, 0);
4bac9ae4 2137 SvTAINTED_off(GvSVn(PL_last_in_gv)); /* previous tainting irrelevant */
76f68e9b 2138 sv_setpvs(GvSVn(PL_last_in_gv), "-");
3280af22 2139 SvSETMAGIC(GvSV(PL_last_in_gv));
a2008d6d
GS
2140 fp = IoIFP(io);
2141 goto have_fp;
a0d0e21e
LW
2142 }
2143 }
157fb5a1 2144 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
a0d0e21e 2145 if (!fp) { /* Note: fp != IoIFP(io) */
3280af22 2146 (void)do_close(PL_last_in_gv, FALSE); /* now it does*/
a0d0e21e
LW
2147 }
2148 }
0d44d22b
NC
2149 else if (type == OP_GLOB)
2150 fp = Perl_start_glob(aTHX_ POPs, io);
a0d0e21e
LW
2151 }
2152 else if (type == OP_GLOB)
2153 SP--;
7716c5c5 2154 else if (IoTYPE(io) == IoTYPE_WRONLY) {
a5390457 2155 report_wrongway_fh(PL_last_in_gv, '>');
a00b5bd3 2156 }
a0d0e21e
LW
2157 }
2158 if (!fp) {
041457d9 2159 if ((!io || !(IoFLAGS(io) & IOf_START))
de7dabb6
TC
2160 && ckWARN(WARN_CLOSED)
2161 && type != OP_GLOB)
041457d9 2162 {
de7dabb6 2163 report_evil_fh(PL_last_in_gv);
3f4520fe 2164 }
54310121 2165 if (gimme == G_SCALAR) {
79628082 2166 /* undef TARG, and push that undefined value */
ba92458f 2167 if (type != OP_RCATLINE) {
aab1202a 2168 sv_setsv(TARG,NULL);
ba92458f 2169 }
a0d0e21e
LW
2170 PUSHTARG;
2171 }
2172 RETURN;
2173 }
a2008d6d 2174 have_fp:
54310121 2175 if (gimme == G_SCALAR) {
a0d0e21e 2176 sv = TARG;
0f722b55
RGS
2177 if (type == OP_RCATLINE && SvGMAGICAL(sv))
2178 mg_get(sv);
48de12d9
RGS
2179 if (SvROK(sv)) {
2180 if (type == OP_RCATLINE)
5668452f 2181 SvPV_force_nomg_nolen(sv);
48de12d9
RGS
2182 else
2183 sv_unref(sv);
2184 }
f7877b28 2185 else if (isGV_with_GP(sv)) {
5668452f 2186 SvPV_force_nomg_nolen(sv);
f7877b28 2187 }
862a34c6 2188 SvUPGRADE(sv, SVt_PV);
a0d0e21e 2189 tmplen = SvLEN(sv); /* remember if already alloced */
e3918bb7 2190 if (!tmplen && !SvREADONLY(sv) && !SvIsCOW(sv)) {
f72e8700
JJ
2191 /* try short-buffering it. Please update t/op/readline.t
2192 * if you change the growth length.
2193 */
2194 Sv_Grow(sv, 80);
2195 }
2b5e58c4
AMS
2196 offset = 0;
2197 if (type == OP_RCATLINE && SvOK(sv)) {
2198 if (!SvPOK(sv)) {
5668452f 2199 SvPV_force_nomg_nolen(sv);
2b5e58c4 2200 }
a0d0e21e 2201 offset = SvCUR(sv);
2b5e58c4 2202 }
a0d0e21e 2203 }
54310121 2204 else {
561b68a9 2205 sv = sv_2mortal(newSV(80));
54310121
PP
2206 offset = 0;
2207 }
fbad3eb5 2208
3887d568
AP
2209 /* This should not be marked tainted if the fp is marked clean */
2210#define MAYBE_TAINT_LINE(io, sv) \
2211 if (!(IoFLAGS(io) & IOf_UNTAINT)) { \
2212 TAINT; \
2213 SvTAINTED_on(sv); \
2214 }
2215
684bef36 2216/* delay EOF state for a snarfed empty file */
fbad3eb5 2217#define SNARF_EOF(gimme,rs,io,sv) \
684bef36 2218 (gimme != G_SCALAR || SvCUR(sv) \
b9fee9ba 2219 || (IoFLAGS(io) & IOf_NOLINE) || !RsSNARF(rs))
fbad3eb5 2220
a0d0e21e 2221 for (;;) {
09e8efcc 2222 PUTBACK;
fbad3eb5 2223 if (!sv_gets(sv, fp, offset)
2d726892
TF
2224 && (type == OP_GLOB
2225 || SNARF_EOF(gimme, PL_rs, io, sv)
2226 || PerlIO_error(fp)))
fbad3eb5 2227 {
760ac839 2228 PerlIO_clearerr(fp);
a0d0e21e 2229 if (IoFLAGS(io) & IOf_ARGV) {
157fb5a1 2230 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
a0d0e21e
LW
2231 if (fp)
2232 continue;
3280af22 2233 (void)do_close(PL_last_in_gv, FALSE);
a0d0e21e
LW
2234 }
2235 else if (type == OP_GLOB) {
a2a5de95
NC
2236 if (!do_close(PL_last_in_gv, FALSE)) {
2237 Perl_ck_warner(aTHX_ packWARN(WARN_GLOB),
2238 "glob failed (child exited with status %d%s)",
2239 (int)(STATUS_CURRENT >> 8),
2240 (STATUS_CURRENT & 0x80) ? ", core dumped" : "");
4eb79ab5 2241 }
a0d0e21e 2242 }
54310121 2243 if (gimme == G_SCALAR) {
ba92458f
AE
2244 if (type != OP_RCATLINE) {
2245 SV_CHECK_THINKFIRST_COW_DROP(TARG);
0c34ef67 2246 SvOK_off(TARG);
ba92458f 2247 }
09e8efcc 2248 SPAGAIN;
a0d0e21e
LW
2249 PUSHTARG;
2250 }
3887d568 2251 MAYBE_TAINT_LINE(io, sv);
a0d0e21e
LW
2252 RETURN;
2253 }
3887d568 2254 MAYBE_TAINT_LINE(io, sv);
a0d0e21e 2255 IoLINES(io)++;
b9fee9ba 2256 IoFLAGS(io) |= IOf_NOLINE;
71be2cbc 2257 SvSETMAGIC(sv);
09e8efcc 2258 SPAGAIN;
a0d0e21e 2259 XPUSHs(sv);
a0d0e21e 2260 if (type == OP_GLOB) {
349d4f2f 2261 const char *t1;
45a23732 2262 Stat_t statbuf;
a0d0e21e 2263
3280af22 2264 if (SvCUR(sv) > 0 && SvCUR(PL_rs) > 0) {
6136c704 2265 char * const tmps = SvEND(sv) - 1;
aa07b2f6 2266 if (*tmps == *SvPVX_const(PL_rs)) {
c07a80fd 2267 *tmps = '\0';
b162af07 2268 SvCUR_set(sv, SvCUR(sv) - 1);
c07a80fd
PP
2269 }
2270 }
349d4f2f 2271 for (t1 = SvPVX_const(sv); *t1; t1++)
b51c3e77
CB
2272#ifdef __VMS
2273 if (strchr("*%?", *t1))
2274#else
7ad1e72d 2275 if (strchr("$&*(){}[]'\";\\|?<>~`", *t1))
b51c3e77 2276#endif
a0d0e21e 2277 break;
45a23732 2278 if (*t1 && PerlLIO_lstat(SvPVX_const(sv), &statbuf) < 0) {
a0d0e21e
LW
2279 (void)POPs; /* Unmatched wildcard? Chuck it... */
2280 continue;
2281 }
2d79bf7f 2282 } else if (SvUTF8(sv)) { /* OP_READLINE, OP_RCATLINE */
d4c19fe8
AL
2283 if (ckWARN(WARN_UTF8)) {
2284 const U8 * const s = (const U8*)SvPVX_const(sv) + offset;
2285 const STRLEN len = SvCUR(sv) - offset;
2286 const U8 *f;
2287
2288 if (!is_utf8_string_loc(s, len, &f))
2289 /* Emulate :encoding(utf8) warning in the same case. */
2290 Perl_warner(aTHX_ packWARN(WARN_UTF8),
2291 "utf8 \"\\x%02X\" does not map to Unicode",
2292 f < (U8*)SvEND(sv) ? *f : 0);
2293 }
a0d0e21e 2294 }
54310121 2295 if (gimme == G_ARRAY) {
a0d0e21e 2296 if (SvLEN(sv) - SvCUR(sv) > 20) {
1da4ca5f 2297 SvPV_shrink_to_cur(sv);
a0d0e21e 2298 }
561b68a9 2299 sv = sv_2mortal(newSV(80));
a0d0e21e
LW
2300 continue;
2301 }
54310121 2302 else if (gimme == G_SCALAR && !tmplen && SvLEN(sv) - SvCUR(sv) > 80) {
a0d0e21e 2303 /* try to reclaim a bit of scalar space (only on 1st alloc) */
d5b5861b
NC
2304 const STRLEN new_len
2305 = SvCUR(sv) < 60 ? 80 : SvCUR(sv)+40; /* allow some slop */
1da4ca5f 2306 SvPV_renew(sv, new_len);
a0d0e21e
LW
2307 }
2308 RETURN;
2309 }
2310}
2311
a0d0e21e
LW
2312PP(pp_helem)
2313{
20b7effb 2314 dSP;
760ac839 2315 HE* he;
ae77835f 2316 SV **svp;
c445ea15 2317 SV * const keysv = POPs;
85fbaab2 2318 HV * const hv = MUTABLE_HV(POPs);
a3b680e6
AL
2319 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2320 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
be6c24e0 2321 SV *sv;
92970b93 2322 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
d30e492c 2323 bool preeminent = TRUE;
a0d0e21e 2324
6dfc73ea
SM
2325 if (SvTYPE(hv) != SVt_PVHV)
2326 RETPUSHUNDEF;
d4c19fe8 2327
92970b93 2328 if (localizing) {
d4c19fe8
AL
2329 MAGIC *mg;
2330 HV *stash;
d30e492c
VP
2331
2332 /* If we can determine whether the element exist,
2333 * Try to preserve the existenceness of a tied hash
2334 * element by using EXISTS and DELETE if possible.
2335 * Fallback to FETCH and STORE otherwise. */
2c5f48c2 2336 if (SvCANEXISTDELETE(hv))
d30e492c 2337 preeminent = hv_exists_ent(hv, keysv, 0);
d4c19fe8 2338 }
d30e492c 2339
5f9d7e2b 2340 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
d4c19fe8 2341 svp = he ? &HeVAL(he) : NULL;
a0d0e21e 2342 if (lval) {
746f6409 2343 if (!svp || !*svp || *svp == &PL_sv_undef) {
68dc0745
PP
2344 SV* lv;
2345 SV* key2;
2d8e6c8d 2346 if (!defer) {
be2597df 2347 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2d8e6c8d 2348 }
68dc0745
PP
2349 lv = sv_newmortal();
2350 sv_upgrade(lv, SVt_PVLV);
2351 LvTYPE(lv) = 'y';
6136c704 2352 sv_magic(lv, key2 = newSVsv(keysv), PERL_MAGIC_defelem, NULL, 0);
fc2b2dca 2353 SvREFCNT_dec_NN(key2); /* sv_magic() increments refcount */
0ad694a7 2354 LvTARG(lv) = SvREFCNT_inc_simple_NN(hv);
68dc0745
PP
2355 LvTARGLEN(lv) = 1;
2356 PUSHs(lv);
2357 RETURN;
2358 }
92970b93 2359 if (localizing) {
bfcb3514 2360 if (HvNAME_get(hv) && isGV(*svp))
159b6efe 2361 save_gp(MUTABLE_GV(*svp), !(PL_op->op_flags & OPf_SPECIAL));
47cfc530
VP
2362 else if (preeminent)
2363 save_helem_flags(hv, keysv, svp,
2364 (PL_op->op_flags & OPf_SPECIAL) ? 0 : SAVEf_SETMAGIC);
2365 else
2366 SAVEHDELETE(hv, keysv);
5f05dabc 2367 }
9026059d
GG
2368 else if (PL_op->op_private & OPpDEREF) {
2369 PUSHs(vivify_ref(*svp, PL_op->op_private & OPpDEREF));
2370 RETURN;
2371 }
a0d0e21e 2372 }
746f6409 2373 sv = (svp && *svp ? *svp : &PL_sv_undef);
fd69380d
DM
2374 /* Originally this did a conditional C<sv = sv_mortalcopy(sv)>; this
2375 * was to make C<local $tied{foo} = $tied{foo}> possible.
2376 * However, it seems no longer to be needed for that purpose, and
2377 * introduced a new bug: stuff like C<while ($hash{taintedval} =~ /.../g>
2378 * would loop endlessly since the pos magic is getting set on the
2379 * mortal copy and lost. However, the copy has the effect of
2380 * triggering the get magic, and losing it altogether made things like
2381 * c<$tied{foo};> in void context no longer do get magic, which some
2382 * code relied on. Also, delayed triggering of magic on @+ and friends
2383 * meant the original regex may be out of scope by now. So as a
2384 * compromise, do the get magic here. (The MGf_GSKIP flag will stop it
2385 * being called too many times). */
39cf747a 2386 if (!lval && SvRMAGICAL(hv) && SvGMAGICAL(sv))
fd69380d 2387 mg_get(sv);
be6c24e0 2388 PUSHs(sv);
a0d0e21e
LW
2389 RETURN;
2390}
2391
fedf30e1
DM
2392
2393/* a stripped-down version of Perl_softref2xv() for use by
2394 * pp_multideref(), which doesn't use PL_op->op_flags */
2395
f9db5646 2396STATIC GV *
fedf30e1
DM
2397S_softref2xv_lite(pTHX_ SV *const sv, const char *const what,
2398 const svtype type)
2399{
2400 if (PL_op->op_private & HINT_STRICT_REFS) {
2401 if (SvOK(sv))
2402 Perl_die(aTHX_ PL_no_symref_sv, sv,
2403 (SvPOKp(sv) && SvCUR(sv)>32 ? "..." : ""), what);
2404 else
2405 Perl_die(aTHX_ PL_no_usym, what);
2406 }
2407 if (!SvOK(sv))
2408 Perl_die(aTHX_ PL_no_usym, what);
2409 return gv_fetchsv_nomg(sv, GV_ADD, type);
2410}
2411
2412
79815f56
DM
2413/* Handle one or more aggregate derefs and array/hash indexings, e.g.
2414 * $h->{foo} or $a[0]{$key}[$i] or f()->[1]
fedf30e1
DM
2415 *
2416 * op_aux points to an array of unions of UV / IV / SV* / PADOFFSET.
79815f56
DM
2417 * Each of these either contains a set of actions, or an argument, such as
2418 * an IV to use as an array index, or a lexical var to retrieve.
2419 * Several actions re stored per UV; we keep shifting new actions off the
2420 * one UV, and only reload when it becomes zero.
fedf30e1
DM
2421 */
2422
2423PP(pp_multideref)
2424{
2425 SV *sv = NULL; /* init to avoid spurious 'may be used uninitialized' */
2426 UNOP_AUX_item *items = cUNOP_AUXx(PL_op)->op_aux;
2427 UV actions = items->uv;
2428
2429 assert(actions);
2430 /* this tells find_uninit_var() where we're up to */
2431 PL_multideref_pc = items;
2432
2433 while (1) {
2434 /* there are three main classes of action; the first retrieve
2435 * the initial AV or HV from a variable or the stack; the second
2436 * does the equivalent of an unrolled (/DREFAV, rv2av, aelem),
2437 * the third an unrolled (/DREFHV, rv2hv, helem).
2438 */
2439 switch (actions & MDEREF_ACTION_MASK) {
2440
2441 case MDEREF_reload:
2442 actions = (++items)->uv;
2443 continue;
2444
2445 case MDEREF_AV_padav_aelem: /* $lex[...] */
2446 sv = PAD_SVl((++items)->pad_offset);
2447 goto do_AV_aelem;
2448
2449 case MDEREF_AV_gvav_aelem: /* $pkg[...] */
2450 sv = UNOP_AUX_item_sv(++items);
2451 assert(isGV_with_GP(sv));
2452 sv = (SV*)GvAVn((GV*)sv);
2453 goto do_AV_aelem;
2454
2455 case MDEREF_AV_pop_rv2av_aelem: /* expr->[...] */
2456 {
2457 dSP;
2458 sv = POPs;
2459 PUTBACK;
2460 goto do_AV_rv2av_aelem;
2461 }
2462
2463 case MDEREF_AV_gvsv_vivify_rv2av_aelem: /* $pkg->[...] */
2464 sv = UNOP_AUX_item_sv(++items);
2465 assert(isGV_with_GP(sv));
2466 sv = GvSVn((GV*)sv);
2467 goto do_AV_vivify_rv2av_aelem;
2468
2469 case MDEREF_AV_padsv_vivify_rv2av_aelem: /* $lex->[...] */
2470 sv = PAD_SVl((++items)->pad_offset);
2471 /* FALLTHROUGH */
2472
2473 do_AV_vivify_rv2av_aelem:
2474 case MDEREF_AV_vivify_rv2av_aelem: /* vivify, ->[...] */
2475 /* this is the OPpDEREF action normally found at the end of
2476 * ops like aelem, helem, rv2sv */
2477 sv = vivify_ref(sv, OPpDEREF_AV);
2478 /* FALLTHROUGH */
2479
2480 do_AV_rv2av_aelem:
2481 /* this is basically a copy of pp_rv2av when it just has the
2482 * sKR/1 flags */
2483 SvGETMAGIC(sv);
2484 if (LIKELY(SvROK(sv))) {
2485 if (UNLIKELY(SvAMAGIC(sv))) {
2486 sv = amagic_deref_call(sv, to_av_amg);
2487 }
2488 sv = SvRV(sv);
2489 if (UNLIKELY(SvTYPE(sv) != SVt_PVAV))
2490 DIE(aTHX_ "Not an ARRAY reference");
2491 }
2492 else if (SvTYPE(sv) != SVt_PVAV) {
2493 if (!isGV_with_GP(sv))
2494 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "an ARRAY", SVt_PVAV);
2495 sv = MUTABLE_SV(GvAVn((GV*)sv));
2496 }
2497 /* FALLTHROUGH */
2498
2499 do_AV_aelem:
2500 {
2501 /* retrieve the key; this may be either a lexical or package
2502 * var (whose index/ptr is stored as an item) or a signed
2503 * integer constant stored as an item.
2504 */
2505 SV *elemsv;
2506 IV elem = 0; /* to shut up stupid compiler warnings */
2507
2508
2509 assert(SvTYPE(sv) == SVt_PVAV);
2510
2511 switch (actions & MDEREF_INDEX_MASK) {
2512 case MDEREF_INDEX_none:
2513 goto finish;
2514 case MDEREF_INDEX_const:
2515 elem = (++items)->iv;
2516 break;
2517 case MDEREF_INDEX_padsv:
2518 elemsv = PAD_SVl((++items)->pad_offset);
2519 goto check_elem;
2520 case MDEREF_INDEX_gvsv:
2521 elemsv = UNOP_AUX_item_sv(++items);
2522 assert(isGV_with_GP(elemsv));
2523 elemsv = GvSVn((GV*)elemsv);
2524 check_elem:
2525 if (UNLIKELY(SvROK(elemsv) && !SvGAMAGIC(elemsv)
2526 && ckWARN(WARN_MISC)))
2527 Perl_warner(aTHX_ packWARN(WARN_MISC),
2528 "Use of reference \"%"SVf"\" as array index",
2529 SVfARG(elemsv));
2530 /* the only time that S_find_uninit_var() needs this
2531 * is to determine which index value triggered the
2532 * undef warning. So just update it here. Note that
2533 * since we don't save and restore this var (e.g. for
2534 * tie or overload execution), its value will be
2535 * meaningless apart from just here */
2536 PL_multideref_pc = items;
2537 elem = SvIV(elemsv);
2538 break;
2539 }
2540
2541
2542 /* this is basically a copy of pp_aelem with OPpDEREF skipped */
2543
2544 if (!(actions & MDEREF_FLAG_last)) {
2545 SV** svp = av_fetch((AV*)sv, elem, 1);
2546 if (!svp || ! (sv=*svp))
2547 DIE(aTHX_ PL_no_aelem, elem);
2548 break;
2549 }
2550
2551 if (PL_op->op_private &
2552 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
2553 {
2554 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
2555 sv = av_exists((AV*)sv, elem) ? &PL_sv_yes : &PL_sv_no;
2556 }
2557 else {
2558 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
2559 sv = av_delete((AV*)sv, elem, discard);
2560 if (discard)
2561 return NORMAL;
2562 if (!sv)
2563 sv = &PL_sv_undef;
2564 }
2565 }
2566 else {
2567 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2568 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
2569 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
2570 bool preeminent = TRUE;
2571 AV *const av = (AV*)sv;
2572 SV** svp;
2573
2574 if (UNLIKELY(localizing)) {
2575 MAGIC *mg;
2576 HV *stash;
2577
2578 /* If we can determine whether the element exist,
2579 * Try to preserve the existenceness of a tied array
2580 * element by using EXISTS and DELETE if possible.
2581 * Fallback to FETCH and STORE otherwise. */
2582 if (SvCANEXISTDELETE(av))
2583 preeminent = av_exists(av, elem);
2584 }
2585
2586 svp = av_fetch(av, elem, lval && !defer);
2587
2588 if (lval) {
2589 if (!svp || !(sv = *svp)) {
2590 IV len;
2591 if (!defer)
2592 DIE(aTHX_ PL_no_aelem, elem);
2593 len = av_tindex(av);
2594 sv = sv_2mortal(newSVavdefelem(av,
2595 /* Resolve a negative index now, unless it points
2596 * before the beginning of the array, in which
2597 * case record it for error reporting in
2598 * magic_setdefelem. */
2599 elem < 0 && len + elem >= 0
2600 ? len + elem : elem, 1));
2601 }
2602 else {
2603 if (UNLIKELY(localizing)) {
2604 if (preeminent) {
2605 save_aelem(av, elem, svp);
2606 sv = *svp; /* may have changed */
2607 }
2608 else
2609 SAVEADELETE(av, elem);
2610 }
2611 }
2612 }
2613 else {
2614 sv = (svp ? *svp : &PL_sv_undef);
2615 /* see note in pp_helem() */
2616 if (SvRMAGICAL(av) && SvGMAGICAL(sv))
2617 mg_get(sv);
2618 }
2619 }
2620
2621 }
2622 finish:
2623 {
2624 dSP;
2625 XPUSHs(sv);
2626 RETURN;
2627 }
2628 /* NOTREACHED */
2629
2630
2631
2632
2633 case MDEREF_HV_padhv_helem: /* $lex{...} */
2634 sv = PAD_SVl((++items)->pad_offset);
2635 goto do_HV_helem;
2636
2637 case MDEREF_HV_gvhv_helem: /* $pkg{...} */
2638 sv = UNOP_AUX_item_sv(++items);
2639 assert(isGV_with_GP(sv));
2640 sv = (SV*)GvHVn((GV*)sv);
2641 goto do_HV_helem;
2642
2643 case MDEREF_HV_pop_rv2hv_helem: /* expr->{...} */
2644 {
2645 dSP;
2646 sv = POPs;
2647 PUTBACK;
2648 goto do_HV_rv2hv_helem;
2649 }
2650
2651 case MDEREF_HV_gvsv_vivify_rv2hv_helem: /* $pkg->{...} */
2652 sv = UNOP_AUX_item_sv(++items);
2653 assert(isGV_with_GP(sv));
2654 sv = GvSVn((GV*)sv);
2655 goto do_HV_vivify_rv2hv_helem;
2656
2657 case MDEREF_HV_padsv_vivify_rv2hv_helem: /* $lex->{...} */
2658 sv = PAD_SVl((++items)->pad_offset);
2659 /* FALLTHROUGH */
2660
2661 do_HV_vivify_rv2hv_helem:
2662 case MDEREF_HV_vivify_rv2hv_helem: /* vivify, ->{...} */
2663 /* this is the OPpDEREF action normally found at the end of
2664 * ops like aelem, helem, rv2sv */
2665 sv = vivify_ref(sv, OPpDEREF_HV);
2666 /* FALLTHROUGH */
2667
2668 do_HV_rv2hv_helem:
2669 /* this is basically a copy of pp_rv2hv when it just has the
2670 * sKR/1 flags (and pp_rv2hv is aliased to pp_rv2av) */
2671
2672 SvGETMAGIC(sv);
2673 if (LIKELY(SvROK(sv))) {
2674 if (UNLIKELY(SvAMAGIC(sv))) {
2675 sv = amagic_deref_call(sv, to_hv_amg);
2676 }
2677 sv = SvRV(sv);
2678 if (UNLIKELY(SvTYPE(sv) != SVt_PVHV))
2679 DIE(aTHX_ "Not a HASH reference");
2680 }
2681 else if (SvTYPE(sv) != SVt_PVHV) {
2682 if (!isGV_with_GP(sv))
2683 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "a HASH", SVt_PVHV);
2684 sv = MUTABLE_SV(GvHVn((GV*)sv));
2685 }
2686 /* FALLTHROUGH */
2687
2688 do_HV_helem:
2689 {
2690 /* retrieve the key; this may be either a lexical / package
2691 * var or a string constant, whose index/ptr is stored as an
2692 * item
2693 */
2694 SV *keysv = NULL; /* to shut up stupid compiler warnings */
2695
2696 assert(SvTYPE(sv) == SVt_PVHV);
2697
2698 switch (actions & MDEREF_INDEX_MASK) {
2699 case MDEREF_INDEX_none:
2700 goto finish;
2701
2702 case MDEREF_INDEX_const:
2703 keysv = UNOP_AUX_item_sv(++items);
2704 break;
2705
2706 case MDEREF_INDEX_padsv:
2707 keysv = PAD_SVl((++items)->pad_offset);
2708 break;
2709
2710 case MDEREF_INDEX_gvsv:
2711 keysv = UNOP_AUX_item_sv(++items);
2712 keysv = GvSVn((GV*)keysv);
2713 break;
2714 }
2715
2716 /* see comment above about setting this var */
2717 PL_multideref_pc = items;
2718
2719
2720 /* ensure that candidate CONSTs have been HEKified */
2721 assert( ((actions & MDEREF_INDEX_MASK) != MDEREF_INDEX_const)
2722 || SvTYPE(keysv) >= SVt_PVMG
2723 || !SvOK(keysv)
2724 || SvROK(keysv)
2725 || SvIsCOW_shared_hash(keysv));
2726
2727 /* this is basically a copy of pp_helem with OPpDEREF skipped */
2728
2729 if (!(actions & MDEREF_FLAG_last)) {
2730 HE *he = hv_fetch_ent((HV*)sv, keysv, 1, 0);
2731 if (!he || !(sv=HeVAL(he)) || sv == &PL_sv_undef)
2732 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2733 break;
2734 }
2735
2736 if (PL_op->op_private &
2737 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
2738 {
2739 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
2740 sv = hv_exists_ent((HV*)sv, keysv, 0)
2741 ? &PL_sv_yes : &PL_sv_no;
2742 }
2743 else {
2744 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
2745 sv = hv_delete_ent((HV*)sv, keysv, discard, 0);
2746 if (discard)
2747 return NORMAL;
2748 if (!sv)
2749 sv = &PL_sv_undef;
2750 }
2751 }
2752 else {
2753 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2754 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
2755 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
2756 bool preeminent = TRUE;
2757 SV **svp;
2758 HV * const hv = (HV*)sv;
2759 HE* he;
2760
2761 if (UNLIKELY(localizing)) {
2762 MAGIC *mg;
2763 HV *stash;
2764
2765 /* If we can determine whether the element exist,
2766 * Try to preserve the existenceness of a tied hash
2767 * element by using EXISTS and DELETE if possible.
2768 * Fallback to FETCH and STORE otherwise. */
2769 if (SvCANEXISTDELETE(hv))
2770 preeminent = hv_exists_ent(hv, keysv, 0);
2771 }
2772
2773 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
2774 svp = he ? &HeVAL(he) : NULL;
2775
2776
2777 if (lval) {
2778 if (!svp || !(sv = *svp) || sv == &PL_sv_undef) {
2779 SV* lv;
2780 SV* key2;
2781 if (!defer)
2782 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2783 lv = sv_newmortal();
2784 sv_upgrade(lv, SVt_PVLV);
2785 LvTYPE(lv) = 'y';
2786 sv_magic(lv, key2 = newSVsv(keysv),
2787 PERL_MAGIC_defelem, NULL, 0);
2788 /* sv_magic() increments refcount */
2789 SvREFCNT_dec_NN(key2);
0ad694a7 2790 LvTARG(lv) = SvREFCNT_inc_simple_NN(hv);
fedf30e1
DM
2791 LvTARGLEN(lv) = 1;
2792 sv = lv;
2793 }
2794 else {
2795 if (localizing) {
2796 if (HvNAME_get(hv) && isGV(sv))
2797 save_gp(MUTABLE_GV(sv),
2798 !(PL_op->op_flags & OPf_SPECIAL));
2799 else if (preeminent) {
2800 save_helem_flags(hv, keysv, svp,
2801 (PL_op->op_flags & OPf_SPECIAL)
2802 ? 0 : SAVEf_SETMAGIC);
2803 sv = *svp; /* may have changed */
2804 }
2805 else
2806 SAVEHDELETE(hv, keysv);
2807 }
2808 }
2809 }
2810 else {
2811 sv = (svp && *svp ? *svp : &PL_sv_undef);
2812 /* see note in pp_helem() */
2813 if (SvRMAGICAL(hv) && SvGMAGICAL(sv))
2814 mg_get(sv);
2815 }
2816 }
2817 goto finish;
2818 }
2819
2820 } /* switch */
2821
2822 actions >>= MDEREF_SHIFT;
2823 } /* while */
2824 /* NOTREACHED */
2825}
2826
2827
a0d0e21e
LW
2828PP(pp_iter)
2829{
eb578fdb 2830 PERL_CONTEXT *cx;
7d6c2cef 2831 SV *oldsv;
1d7c1841 2832 SV **itersvp;
8a1f10dd 2833 SV *retsv;
a0d0e21e 2834
84f05d57
JH
2835 SV *sv;
2836 AV *av;
2837 IV ix;
2838 IV inc;
2839
4ebe6e95 2840 cx = CX_CUR();
1d7c1841 2841 itersvp = CxITERVAR(cx);
4b5c941e 2842 assert(itersvp);
a48ce6be
DM
2843
2844 switch (CxTYPE(cx)) {
17c91640 2845
b552b52c
DM
2846 case CXt_LOOP_LAZYSV: /* string increment */
2847 {
2848 SV* cur = cx->blk_loop.state_u.lazysv.cur;
2849 SV *end = cx->blk_loop.state_u.lazysv.end;
2850 /* If the maximum is !SvOK(), pp_enteriter substitutes PL_sv_no.
2851 It has SvPVX of "" and SvCUR of 0, which is what we want. */
2852 STRLEN maxlen = 0;
2853 const char *max = SvPV_const(end, maxlen);
5d9574c1 2854 if (UNLIKELY(SvNIOK(cur) || SvCUR(cur) > maxlen))
8a1f10dd 2855 goto retno;
b552b52c
DM
2856
2857 oldsv = *itersvp;
6d3ca00e
DM
2858 /* NB: on the first iteration, oldsv will have a ref count of at
2859 * least 2 (one extra from blk_loop.itersave), so the GV or pad
2860 * slot will get localised; on subsequent iterations the RC==1
2861 * optimisation may kick in and the SV will be reused. */
2862 if (oldsv && LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
b552b52c
DM
2863 /* safe to reuse old SV */
2864 sv_setsv(oldsv, cur);
a48ce6be 2865 }
b552b52c
DM
2866 else
2867 {
2868 /* we need a fresh SV every time so that loop body sees a
2869 * completely new SV for closures/references to work as
2870 * they used to */
2871 *itersvp = newSVsv(cur);
6d3ca00e 2872 SvREFCNT_dec(oldsv);
b552b52c
DM
2873 }
2874 if (strEQ(SvPVX_const(cur), max))
2875 sv_setiv(cur, 0); /* terminate next time */
2876 else
2877 sv_inc(cur);
2878 break;
2879 }
a48ce6be 2880
fcef60b4
DM
2881 case CXt_LOOP_LAZYIV: /* integer increment */
2882 {
2883 IV cur = cx->blk_loop.state_u.lazyiv.cur;
5d9574c1 2884 if (UNLIKELY(cur > cx->blk_loop.state_u.lazyiv.end))
8a1f10dd 2885 goto retno;
7f61b687 2886
fcef60b4 2887 oldsv = *itersvp;
6d3ca00e
DM
2888 /* see NB comment above */
2889 if (oldsv && LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
eaa5c2d6 2890 /* safe to reuse old SV */
47b96a1e
DM
2891
2892 if ( (SvFLAGS(oldsv) & (SVTYPEMASK|SVf_THINKFIRST|SVf_IVisUV))
2893 == SVt_IV)
2894 {
2895 /* Cheap SvIOK_only().
2896 * Assert that flags which SvIOK_only() would test or
2897 * clear can't be set, because we're SVt_IV */
2898 assert(!(SvFLAGS(oldsv) &
2899 (SVf_OOK|SVf_UTF8|(SVf_OK & ~(SVf_IOK|SVp_IOK)))));
2900 SvFLAGS(oldsv) |= (SVf_IOK|SVp_IOK);
2901 /* SvIV_set() where sv_any points to head */
2902 oldsv->sv_u.svu_iv = cur;
2903
2904 }
2905 else
2906 sv_setiv(oldsv, cur);
eaa5c2d6 2907 }
1c846c1f 2908 else
eaa5c2d6
GA
2909 {
2910 /* we need a fresh SV every time so that loop body sees a
2911 * completely new SV for closures/references to work as they
2912 * used to */
fcef60b4 2913 *itersvp = newSViv(cur);
6d3ca00e 2914 SvREFCNT_dec(oldsv);
eaa5c2d6 2915 }
a2309040 2916
5d9574c1 2917 if (UNLIKELY(cur == IV_MAX)) {
cdc1aa42
NC
2918 /* Handle end of range at IV_MAX */
2919 cx->blk_loop.state_u.lazyiv.end = IV_MIN;
2920 } else
2921 ++cx->blk_loop.state_u.lazyiv.cur;
a48ce6be 2922 break;
fcef60b4 2923 }
a48ce6be 2924
93661e56
DM
2925 case CXt_LOOP_LIST: /* for (1,2,3) */
2926
2927 assert(OPpITER_REVERSED == 2); /* so inc becomes -1 or 1 */
2928 inc = 1 - (PL_op->op_private & OPpITER_REVERSED);
2929 ix = (cx->blk_loop.state_u.stack.ix += inc);
2930 if (UNLIKELY(inc > 0
2931 ? ix > cx->blk_oldsp
2932 : ix <= cx->blk_loop.state_u.stack.basesp)
2933 )
8a1f10dd 2934 goto retno;
93661e56
DM
2935
2936 sv = PL_stack_base[ix];
2937 av = NULL;
2938 goto loop_ary_common;
2939
2940 case CXt_LOOP_ARY: /* for (@ary) */
2941
2942 av = cx->blk_loop.state_u.ary.ary;
2943 inc = 1 - (PL_op->op_private & OPpITER_REVERSED);
2944 ix = (cx->blk_loop.state_u.ary.ix += inc);
2945 if (UNLIKELY(inc > 0
2946 ? ix > AvFILL(av)
2947 : ix < 0)
2948 )
8a1f10dd 2949 goto retno;
de080daa 2950
9d1ee8e0 2951 if (UNLIKELY(SvRMAGICAL(av))) {
a8a20bb6
DM
2952 SV * const * const svp = av_fetch(av, ix, FALSE);
2953 sv = svp ? *svp : NULL;
2954 }
2955 else {
2956 sv = AvARRAY(av)[ix];
de080daa 2957 }
ef3e5ea9 2958
93661e56
DM
2959 loop_ary_common:
2960
d39c26a6
FC
2961 if (UNLIKELY(cx->cx_type & CXp_FOR_LVREF)) {
2962 SvSetMagicSV(*itersvp, sv);
2963 break;
2964 }
2965
5d9574c1
DM
2966 if (LIKELY(sv)) {
2967 if (UNLIKELY(SvIS_FREED(sv))) {
f38aa882
DM
2968 *itersvp = NULL;
2969 Perl_croak(aTHX_ "Use of freed value in iteration");
2970 }
60779a30 2971 if (SvPADTMP(sv)) {
8e079c2a 2972 sv = newSVsv(sv);
60779a30 2973 }
8e079c2a
FC
2974 else {
2975 SvTEMP_off(sv);
2976 SvREFCNT_inc_simple_void_NN(sv);
2977 }
de080daa 2978 }
93661e56 2979 else if (av) {
199f858d 2980 sv = newSVavdefelem(av, ix, 0);
de080daa 2981 }
a600f7e6
FC
2982 else
2983 sv = &PL_sv_undef;
a0d0e21e 2984
de080daa
DM
2985 oldsv = *itersvp;
2986 *itersvp = sv;
2987 SvREFCNT_dec(oldsv);
de080daa 2988 break;
a48ce6be
DM
2989
2990 default:
2991 DIE(aTHX_ "panic: pp_iter, type=%u", CxTYPE(cx));
2992 }
8a1f10dd
DM
2993
2994 retsv = &PL_sv_yes;
2995 if (0) {
2996 retno:
2997 retsv = &PL_sv_no;
2998 }
2999 /* pp_enteriter should have pre-extended the stack */
3000 assert(PL_stack_sp < PL_stack_max);
3001 *++PL_stack_sp =retsv;
3002
3003 return PL_op->op_next;
a0d0e21e
LW
3004}
3005
ef07e810
DM
3006/*
3007A description of how taint works in pattern matching and substitution.
3008
284167a5
SM
3009This is all conditional on NO_TAINT_SUPPORT not being defined. Under
3010NO_TAINT_SUPPORT, taint-related operations should become no-ops.
3011
4e19c54b 3012While the pattern is being assembled/concatenated and then compiled,
284167a5
SM
3013PL_tainted will get set (via TAINT_set) if any component of the pattern
3014is tainted, e.g. /.*$tainted/. At the end of pattern compilation,
3015the RXf_TAINTED flag is set on the pattern if PL_tainted is set (via
1738e041
DM
3016TAINT_get). It will also be set if any component of the pattern matches
3017based on locale-dependent behavior.
ef07e810 3018
0ab462a6
DM
3019When the pattern is copied, e.g. $r = qr/..../, the SV holding the ref to
3020the pattern is marked as tainted. This means that subsequent usage, such
284167a5
SM
3021as /x$r/, will set PL_tainted using TAINT_set, and thus RXf_TAINTED,
3022on the new pattern too.
ef07e810 3023
272d35c9 3024RXf_TAINTED_SEEN is used post-execution by the get magic code
ef07e810
DM
3025of $1 et al to indicate whether the returned value should be tainted.
3026It is the responsibility of the caller of the pattern (i.e. pp_match,
3027pp_subst etc) to set this flag for any other circumstances where $1 needs
3028to be tainted.
3029
3030The taint behaviour of pp_subst (and pp_substcont) is quite complex.
3031
3032There are three possible sources of taint
3033 * the source string
3034 * the pattern (both compile- and run-time, RXf_TAINTED / RXf_TAINTED_SEEN)
3035 * the replacement string (or expression under /e)
3036
3037There are four destinations of taint and they are affected by the sources
3038according to the rules below:
3039
3040 * the return value (not including /r):
3041 tainted by the source string and pattern, but only for the
3042 number-of-iterations case; boolean returns aren't tainted;
3043 * the modified string (or modified copy under /r):
3044 tainted by the source string, pattern, and replacement strings;
3045 * $1 et al:
3046 tainted by the pattern, and under 'use re "taint"', by the source
3047 string too;
3048 * PL_taint - i.e. whether subsequent code (e.g. in a /e block) is tainted:
3049 should always be unset before executing subsequent code.
3050
3051The overall action of pp_subst is:
3052
3053 * at the start, set bits in rxtainted indicating the taint status of
3054 the various sources.
3055
3056 * After each pattern execution, update the SUBST_TAINT_PAT bit in
3057 rxtainted if RXf_TAINTED_SEEN has been set, to indicate that the
3058 pattern has subsequently become tainted via locale ops.
3059
3060 * If control is being passed to pp_substcont to execute a /e block,
3061 save rxtainted in the CXt_SUBST block, for future use by
3062 pp_substcont.
3063
3064 * Whenever control is being returned to perl code (either by falling
3065 off the "end" of pp_subst/pp_substcont, or by entering a /e block),
3066 use the flag bits in rxtainted to make all the appropriate types of
0ab462a6
DM
3067 destination taint visible; e.g. set RXf_TAINTED_SEEN so that $1
3068 et al will appear tainted.
ef07e810
DM
3069
3070pp_match is just a simpler version of the above.
3071
3072*/
3073
a0d0e21e
LW
3074PP(pp_subst)
3075{
20b7effb 3076 dSP; dTARG;
eb578fdb 3077 PMOP *pm = cPMOP;
a0d0e21e 3078 PMOP *rpm = pm;
eb578fdb 3079 char *s;
a0d0e21e 3080 char *strend;
5c144d81 3081 const char *c;
a0d0e21e 3082 STRLEN clen;
3c6ef0a5
FC
3083 SSize_t iters = 0;
3084 SSize_t maxiters;
a0d0e21e 3085 bool once;
ef07e810
DM
3086 U8 rxtainted = 0; /* holds various SUBST_TAINT_* flag bits.
3087 See "how taint works" above */
a0d0e21e 3088 char *orig;
1ed74d04 3089 U8 r_flags;
eb578fdb 3090 REGEXP *rx = PM_GETRE(pm);
a0d0e21e
LW
3091 STRLEN len;
3092 int force_on_match = 0;
0bcc34c2 3093 const I32 oldsave = PL_savestack_ix;
792b2c16 3094 STRLEN slen;
26a74523 3095 bool doutf8 = FALSE; /* whether replacement is in utf8 */
db2c6cb3 3096#ifdef PERL_ANY_COW
106d9a13 3097 bool was_cow;
ed252734 3098#endif
a0714e2c 3099 SV *nsv = NULL;
b770e143 3100 /* known replacement string? */
eb578fdb 3101 SV *dstr = (pm->op_pmflags & PMf_CONST) ? POPs : NULL;
a0d0e21e 3102
f410a211
NC
3103 PERL_ASYNC_CHECK();
3104
533c011a 3105 if (PL_op->op_flags & OPf_STACKED)
a0d0e21e 3106 TARG = POPs;
6ffceeb7 3107 else if (ARGTARG)
59f00321 3108 GETTARGET;
a0d0e21e 3109 else {
54b9620d 3110 TARG = DEFSV;
a0d0e21e 3111 EXTEND(SP,1);
1c846c1f 3112 }
d9f424b2 3113
64534138 3114 SvGETMAGIC(TARG); /* must come before cow check */
db2c6cb3 3115#ifdef PERL_ANY_COW
106d9a13
DM
3116 /* note that a string might get converted to COW during matching */
3117 was_cow = cBOOL(SvIsCOW(TARG));
ed252734 3118#endif
d13a5d3b
TC
3119 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
3120#ifndef PERL_ANY_COW
3121 if (SvIsCOW(TARG))
3122 sv_force_normal_flags(TARG,0);
3123#endif
3124 if ((SvREADONLY(TARG)
3125 || ( ((SvTYPE(TARG) == SVt_PVGV && isGV_with_GP(TARG))
3126 || SvTYPE(TARG) > SVt_PVLV)
3127 && !(SvTYPE(TARG) == SVt_PVGV && SvFAKE(TARG)))))
3128 Perl_croak_no_modify();
3129 }
8ec5e241
NIS
3130 PUTBACK;
3131
6ac6605d
DM
3132 orig = SvPV_nomg(TARG, len);
3133 /* note we don't (yet) force the var into being a string; if we fail
92711104 3134 * to match, we leave as-is; on successful match however, we *will*
6ac6605d 3135 * coerce into a string, then repeat the match */
4499db73 3136 if (!SvPOKp(TARG) || SvTYPE(TARG) == SVt_PVGV || SvVOK(TARG))
a0d0e21e 3137 force_on_match = 1;
20be6587
DM
3138
3139 /* only replace once? */
3140 once = !(rpm->op_pmflags & PMf_GLOBAL);
3141
ef07e810 3142 /* See "how taint works" above */
284167a5 3143 if (TAINTING_get) {
20be6587
DM
3144 rxtainted = (
3145 (SvTAINTED(TARG) ? SUBST_TAINT_STR : 0)
284167a5 3146 | (RX_ISTAINTED(rx) ? SUBST_TAINT_PAT : 0)
20be6587
DM
3147 | ((pm->op_pmflags & PMf_RETAINT) ? SUBST_TAINT_RETAINT : 0)
3148 | ((once && !(rpm->op_pmflags & PMf_NONDESTRUCT))
3149 ? SUBST_TAINT_BOOLRET : 0));
3150 TAINT_NOT;
3151 }
a12c0f56 3152
a0d0e21e 3153 force_it:
6ac6605d
DM
3154 if (!pm || !orig)
3155 DIE(aTHX_ "panic: pp_subst, pm=%p, orig=%p", pm, orig);
a0d0e21e 3156
6ac6605d
DM
3157 strend = orig + len;
3158 slen = DO_UTF8(TARG) ? utf8_length((U8*)orig, (U8*)strend) : len;
792b2c16
JH
3159 maxiters = 2 * slen + 10; /* We can match twice at each
3160 position, once with zero-length,
3161 second time with non-zero. */
a0d0e21e 3162
794826f4
YO
3163 /* handle the empty pattern */
3164 if (!RX_PRELEN(rx) && PL_curpm && !ReANY(rx)->mother_re) {
3165 if (PL_curpm == PL_reg_curpm)
31775478 3166 Perl_croak(aTHX_ "Use of the empty pattern inside of "
794826f4 3167 "a regex code block is forbidden");
3280af22 3168 pm = PL_curpm;
aaa362c4 3169 rx = PM_GETRE(pm);
a0d0e21e 3170 }
6502e081 3171
6e240d0b 3172#ifdef PERL_SAWAMPERSAND
6502e081
DM
3173 r_flags = ( RX_NPARENS(rx)
3174 || PL_sawampersand
6502e081 3175 || (RX_EXTFLAGS(rx) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
5b0e71e9 3176 || (rpm->op_pmflags & PMf_KEEPCOPY)
6502e081
DM
3177 )
3178 ? REXEC_COPY_STR
3179 : 0;
6e240d0b
FC
3180#else
3181 r_flags = REXEC_COPY_STR;
3182#endif
7fba1cd6 3183
0395280b 3184 if (!CALLREGEXEC(rx, orig, strend, orig, 0, TARG, NULL, r_flags))
8b64c330 3185 {
5e79dfb9
DM
3186 SPAGAIN;
3187 PUSHs(rpm->op_pmflags & PMf_NONDESTRUCT ? TARG : &PL_sv_no);
3188 LEAVE_SCOPE(oldsave);
3189 RETURN;
3190 }
1754320d
FC
3191 PL_curpm = pm;
3192
71be2cbc 3193 /* known replacement string? */
f272994b 3194 if (dstr) {
8514a05a
JH
3195 /* replacement needing upgrading? */
3196 if (DO_UTF8(TARG) && !doutf8) {
db79b45b 3197 nsv = sv_newmortal();
4a176938 3198 SvSetSV(nsv, dstr);
8df0e7a2 3199 sv_utf8_upgrade(nsv);
5c144d81 3200 c = SvPV_const(nsv, clen);
4a176938
JH
3201 doutf8 = TRUE;
3202 }
3203 else {
5c144d81 3204 c = SvPV_const(dstr, clen);
4a176938 3205 doutf8 = DO_UTF8(dstr);
8514a05a 3206 }
bb933b9b
FC
3207
3208 if (SvTAINTED(dstr))
3209 rxtainted |= SUBST_TAINT_REPL;
f272994b
A
3210 }
3211 else {
6136c704 3212 c = NULL;
f272994b
A
3213 doutf8 = FALSE;
3214 }
3215
71be2cbc 3216 /* can do inplace substitution? */
ed252734 3217 if (c
db2c6cb3 3218#ifdef PERL_ANY_COW
106d9a13 3219 && !was_cow
ed252734 3220#endif
fbfb1899 3221 && (I32)clen <= RX_MINLENRET(rx)
9cefd268
FC
3222 && ( once
3223 || !(r_flags & REXEC_COPY_STR)
3224 || (!SvGMAGICAL(dstr) && !(RX_EXTFLAGS(rx) & RXf_EVAL_SEEN))
3225 )
dbc200c5 3226 && !(RX_EXTFLAGS(rx) & RXf_NO_INPLACE_SUBST)
8ca8a454
NC
3227 && (!doutf8 || SvUTF8(TARG))
3228 && !(rpm->op_pmflags & PMf_NONDESTRUCT))
8b030b38 3229 {
ec911639 3230
db2c6cb3 3231#ifdef PERL_ANY_COW
106d9a13 3232 /* string might have got converted to COW since we set was_cow */
ed252734 3233 if (SvIsCOW(TARG)) {
f7a8268c 3234 if (!force_on_match)
ed252734 3235 goto have_a_cow;
f7a8268c 3236 assert(SvVOK(TARG));
ed252734
NC
3237 }
3238#endif
71be2cbc 3239 if (force_on_match) {
6ac6605d
DM
3240 /* redo the first match, this time with the orig var
3241 * forced into being a string */
71be2cbc 3242 force_on_match = 0;
6ac6605d 3243 orig = SvPV_force_nomg(TARG, len);
71be2cbc
PP
3244 goto force_it;
3245 }
39b40493 3246
71be2cbc 3247 if (once) {
c67ab8f2 3248 char *d, *m;
20be6587
DM
3249 if (RX_MATCH_TAINTED(rx)) /* run time pattern taint, eg locale */
3250 rxtainted |= SUBST_TAINT_PAT;
07bc277f
NC
3251 m = orig + RX_OFFS(rx)[0].start;
3252 d = orig + RX_OFFS(rx)[0].end;
71be2cbc
PP
3253 s = orig;
3254 if (m - s > strend - d) { /* faster to shorten from end */
2ec7214c 3255 I32 i;
71be2cbc
PP
3256 if (clen) {
3257 Copy(c, m, clen, char);
3258 m += clen;
a0d0e21e 3259 }
71be2cbc
PP
3260 i = strend - d;
3261 if (i > 0) {
3262 Move(d, m, i, char);
3263 m += i;
a0d0e21e 3264 }
71be2cbc
PP
3265 *m = '\0';
3266 SvCUR_set(TARG, m - s);
3267 }
2ec7214c
DM
3268 else { /* faster from front */
3269 I32 i = m - s;
71be2cbc 3270 d -= clen;
2ec7214c
DM
3271 if (i > 0)
3272 Move(s, d - i, i, char);
71be2cbc 3273 sv_chop(TARG, d-i);
71be2cbc 3274 if (clen)
c947cd8d 3275 Copy(c, d, clen, char);
71be2cbc 3276 }
8ec5e241 3277 SPAGAIN;
8ca8a454 3278 PUSHs(&PL_sv_yes);
71be2cbc
PP
3279 }
3280 else {
c67ab8f2 3281 char *d, *m;
0395280b 3282 d = s = RX_OFFS(rx)[0].start + orig;
71be2cbc 3283 do {
2b25edcf 3284 I32 i;
5d9574c1 3285 if (UNLIKELY(iters++ > maxiters))
cea2e8a9 3286 DIE(aTHX_ "Substitution loop");
5d9574c1 3287 if (UNLIKELY(RX_MATCH_TAINTED(rx))) /* run time pattern taint, eg locale */
20be6587 3288 rxtainted |= SUBST_TAINT_PAT;
07bc277f 3289 m = RX_OFFS(rx)[0].start + orig;
155aba94 3290 if ((i = m - s)) {
71be2cbc
PP
3291 if (s != d)
3292 Move(s, d, i, char);
3293 d += i;
a0d0e21e 3294 }
71be2cbc
PP
3295 if (clen) {
3296 Copy(c, d, clen, char);
3297 d += clen;
3298 }
07bc277f 3299 s = RX_OFFS(rx)[0].end + orig;
7ce41e5c
FC
3300 } while (CALLREGEXEC(rx, s, strend, orig,
3301 s == m, /* don't match same null twice */
f722798b 3302 TARG, NULL,
d5e7783a 3303 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
71be2cbc 3304 if (s != d) {
2b25edcf 3305 I32 i = strend - s;
aa07b2f6 3306 SvCUR_set(TARG, d - SvPVX_const(TARG) + i);
71be2cbc 3307 Move(s, d, i+1, char); /* include the NUL */
a0d0e21e 3308 }
8ec5e241 3309 SPAGAIN;
3c6ef0a5 3310 mPUSHi(iters);
a0d0e21e
LW
3311 }
3312 }
ff6e92e8 3313 else {
1754320d 3314 bool first;
c67ab8f2 3315 char *m;
1754320d 3316 SV *repl;
a0d0e21e 3317 if (force_on_match) {
6ac6605d
DM
3318 /* redo the first match, this time with the orig var
3319 * forced into being a string */
a0d0e21e 3320 force_on_match = 0;
0c1438a1
NC
3321 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
3322 /* I feel that it should be possible to avoid this mortal copy
3323 given that the code below copies into a new destination.
3324 However, I suspect it isn't worth the complexity of
3325 unravelling the C<goto force_it> for the small number of
3326 cases where it would be viable to drop into the copy code. */
3327 TARG = sv_2mortal(newSVsv(TARG));
3328 }
6ac6605d 3329 orig = SvPV_force_nomg(TARG, len);
a0d0e21e
LW
3330 goto force_it;
3331 }
db2c6cb3 3332#ifdef PERL_ANY_COW
ed252734
NC
3333 have_a_cow:
3334#endif
20be6587
DM
3335 if (RX_MATCH_TAINTED(rx)) /* run time pattern taint, eg locale */
3336 rxtainted |= SUBST_TAINT_PAT;
1754320d 3337 repl = dstr;
0395280b
DM
3338 s = RX_OFFS(rx)[0].start + orig;
3339 dstr = newSVpvn_flags(orig, s-orig,
3340 SVs_TEMP | (DO_UTF8(TARG) ? SVf_UTF8 : 0));
a0d0e21e 3341 if (!c) {
eb578fdb 3342 PERL_CONTEXT *cx;
8ec5e241 3343 SPAGAIN;
0395280b 3344 m = orig;
20be6587
DM
3345 /* note that a whole bunch of local vars are saved here for
3346 * use by pp_substcont: here's a list of them in case you're
3347 * searching for places in this sub that uses a particular var:
3348 * iters maxiters r_flags oldsave rxtainted orig dstr targ
3349 * s m strend rx once */
490576d1 3350 CX_PUSHSUBST(cx);
20e98b0f 3351 RETURNOP(cPMOP->op_pmreplrootu.op_pmreplroot);
a0d0e21e 3352 }
1754320d 3353 first = TRUE;
a0d0e21e 3354 do {
5d9574c1 3355 if (UNLIKELY(iters++ > maxiters))
cea2e8a9 3356 DIE(aTHX_ "Substitution loop");
5d9574c1 3357 if (UNLIKELY(RX_MATCH_TAINTED(rx)))
20be6587 3358 rxtainted |= SUBST_TAINT_PAT;
07bc277f 3359 if (RX_MATCH_COPIED(rx) && RX_SUBBEG(rx) != orig) {
c67ab8f2
DM
3360 char *old_s = s;
3361 char *old_orig = orig;
6502e081 3362 assert(RX_SUBOFFSET(rx) == 0);
c67ab8f2 3363
07bc277f 3364 orig = RX_SUBBEG(rx);
c67ab8f2
DM
3365 s = orig + (old_s - old_orig);
3366 strend = s + (strend - old_s);
a0d0e21e 3367 }
07bc277f 3368 m = RX_OFFS(rx)[0].start + orig;
64534138 3369 sv_catpvn_nomg_maybeutf8(dstr, s, m - s, DO_UTF8(TARG));
07bc277f 3370 s = RX_OFFS(rx)[0].end + orig;
1754320d
FC
3371 if (first) {
3372 /* replacement already stringified */
3373 if (clen)
64534138 3374 sv_catpvn_nomg_maybeutf8(dstr, c, clen, doutf8);
1754320d
FC
3375 first = FALSE;
3376 }
3377 else {
8df0e7a2 3378 sv_catsv(dstr, repl);
5d9574c1 3379 if (UNLIKELY(SvTAINTED(repl)))
bb933b9b 3380 rxtainted |= SUBST_TAINT_REPL;
1754320d 3381 }
a0d0e21e
LW
3382 if (once)
3383 break;
ff27773b
KW
3384 } while (CALLREGEXEC(rx, s, strend, orig,
3385 s == m, /* Yields minend of 0 or 1 */
d5e7783a
DM
3386 TARG, NULL,
3387 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
aba224f7 3388 assert(strend >= s);
64534138 3389 sv_catpvn_nomg_maybeutf8(dstr, s, strend - s, DO_UTF8(TARG));
748a9306 3390
8ca8a454
NC
3391 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
3392 /* From here on down we're using the copy, and leaving the original
3393 untouched. */
3394 TARG = dstr;
3395 SPAGAIN;
3396 PUSHs(dstr);
3397 } else {
db2c6cb3 3398#ifdef PERL_ANY_COW
8ca8a454
NC
3399 /* The match may make the string COW. If so, brilliant, because
3400 that's just saved us one malloc, copy and free - the regexp has
3401 donated the old buffer, and we malloc an entirely new one, rather
3402 than the regexp malloc()ing a buffer and copying our original,
3403 only for us to throw it away here during the substitution. */
3404 if (SvIsCOW(TARG)) {
3405 sv_force_normal_flags(TARG, SV_COW_DROP_PV);
3406 } else
ed252734 3407#endif
8ca8a454
NC
3408 {
3409 SvPV_free(TARG);
3410 }
3411 SvPV_set(TARG, SvPVX(dstr));
3412 SvCUR_set(TARG, SvCUR(dstr));
3413 SvLEN_set(TARG, SvLEN(dstr));
64534138 3414 SvFLAGS(TARG) |= SvUTF8(dstr);
8ca8a454 3415 SvPV_set(dstr, NULL);
748a9306 3416
8ca8a454 3417 SPAGAIN;
3c6ef0a5 3418 mPUSHi(iters);
8ca8a454
NC
3419 }
3420 }
3421
3422 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
3423 (void)SvPOK_only_UTF8(TARG);
a0d0e21e 3424 }
20be6587 3425
ef07e810 3426 /* See "how taint works" above */
284167a5 3427 if (TAINTING_get) {
20be6587
DM
3428 if ((rxtainted & SUBST_TAINT_PAT) ||
3429 ((rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_RETAINT)) ==
3430 (SUBST_TAINT_STR|SUBST_TAINT_RETAINT))
3431 )
3432 (RX_MATCH_TAINTED_on(rx)); /* taint $1 et al */
3433
3434 if (!(rxtainted & SUBST_TAINT_BOOLRET)
3435 && (rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT))
3436 )
3437 SvTAINTED_on(TOPs); /* taint return value */
3438 else
3439 SvTAINTED_off(TOPs); /* may have got tainted earlier */
3440
3441 /* needed for mg_set below */
284167a5
SM
3442 TAINT_set(
3443 cBOOL(rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT|SUBST_TAINT_REPL))
3444 );
20be6587
DM
3445 SvTAINT(TARG);
3446 }
3447 SvSETMAGIC(TARG); /* PL_tainted must be correctly set for this mg_set */
3448 TAINT_NOT;
f1a76097
DM
3449 LEAVE_SCOPE(oldsave);
3450 RETURN;
a0d0e21e
LW
3451}
3452
3453PP(pp_grepwhile)
3454{
20b7effb 3455 dSP;
a0d0e21e
LW
3456
3457 if (SvTRUEx(POPs))
3280af22
NIS
3458 PL_stack_base[PL_markstack_ptr[-1]++] = PL_stack_base[*PL_markstack_ptr];
3459 ++*PL_markstack_ptr;
b2a2a901 3460 FREETMPS;
d343c3ef 3461 LEAVE_with_name("grep_item"); /* exit inner scope */
a0d0e21e
LW
3462
3463 /* All done yet? */
5d9574c1 3464 if (UNLIKELY(PL_stack_base + *PL_markstack_ptr > SP)) {
a0d0e21e 3465 I32 items;
1c23e2bd 3466 const U8 gimme = GIMME_V;
a0d0e21e 3467
d343c3ef 3468 LEAVE_with_name("grep"); /* exit outer scope */
a0d0e21e 3469 (void)POPMARK; /* pop src */
3280af22 3470 items = --*PL_markstack_ptr - PL_markstack_ptr[-1];
a0d0e21e 3471 (void)POPMARK; /* pop dst */
3280af22 3472 SP = PL_stack_base + POPMARK; /* pop original mark */
54310121 3473 if (gimme == G_SCALAR) {
7cc47870
RGS
3474 dTARGET;
3475 XPUSHi(items);
a0d0e21e 3476 }
54310121
PP
3477 else if (gimme == G_ARRAY)
3478 SP += items;
a0d0e21e
LW
3479 RETURN;
3480 }
3481 else {
3482 SV *src;
3483
d343c3ef 3484 ENTER_with_name("grep_item"); /* enter inner scope */
1d7c1841 3485 SAVEVPTR(PL_curpm);
a0d0e21e 3486
6cae08a8 3487 src = PL_stack_base[TOPMARK];
60779a30 3488 if (SvPADTMP(src)) {
6cae08a8 3489 src = PL_stack_base[TOPMARK] = sv_mortalcopy(src);
a0ed822e
FC
3490 PL_tmps_floor++;
3491 }
a0d0e21e 3492 SvTEMP_off(src);
ffd49c98 3493 DEFSV_set(src);
a0d0e21e
LW
3494
3495 RETURNOP(cLOGOP->op_other);
3496 }
3497}
3498
799da9d7 3499/* leave_adjust_stacks():
f7a874b8 3500 *
e02ce34b
DM
3501 * Process a scope's return args (in the range from_sp+1 .. PL_stack_sp),
3502 * positioning them at to_sp+1 onwards, and do the equivalent of a
3503 * FREEMPS and TAINT_NOT.
3504 *
f7a874b8
DM
3505 * Not intended to be called in void context.
3506 *
799da9d7
DM
3507 * When leaving a sub, eval, do{} or other scope, the things that need
3508 * doing to process the return args are:
f7a874b8 3509 * * in scalar context, only return the last arg (or PL_sv_undef if none);
799da9d7
DM
3510 * * for the types of return that return copies of their args (such
3511 * as rvalue sub return), make a mortal copy of every return arg,
3512 * except where we can optimise the copy away without it being
3513 * semantically visible;
3514 * * make sure that the arg isn't prematurely freed; in the case of an
3515 * arg not copied, this may involve mortalising it. For example, in
f7a874b8
DM
3516 * C<sub f { my $x = ...; $x }>, $x would be freed when we do
3517 * CX_LEAVE_SCOPE(cx) unless it's protected or copied.
3518 *
799da9d7
DM
3519 * What condition to use when deciding whether to pass the arg through
3520 * or make a copy, is determined by the 'pass' arg; its valid values are:
3521 * 0: rvalue sub/eval exit
3522 * 1: other rvalue scope exit
3523 * 2: :lvalue sub exit in rvalue context
3524 * 3: :lvalue sub exit in lvalue context and other lvalue scope exits
3525 *
f7a874b8 3526 * There is a big issue with doing a FREETMPS. We would like to free any
799da9d7 3527 * temps created by the last statement which the sub executed, rather than
f7a874b8
DM
3528 * leaving them for the caller. In a situation where a sub call isn't
3529 * soon followed by a nextstate (e.g. nested recursive calls, a la
3530 * fibonacci()), temps can accumulate, causing memory and performance
3531 * issues.
3532 *
3533 * On the other hand, we don't want to free any TEMPs which are keeping
799da9d7
DM
3534 * alive any return args that we skipped copying; nor do we wish to undo
3535 * any mortalising done here.
f7a874b8
DM
3536 *
3537 * The solution is to split the temps stack frame into two, with a cut
3538 * point delineating the two halves. We arrange that by the end of this
3539 * function, all the temps stack frame entries we wish to keep are in the
799da9d7 3540 * range PL_tmps_floor+1.. tmps_base-1, while the ones to free now are in
f7a874b8
DM
3541 * the range tmps_base .. PL_tmps_ix. During the course of this
3542 * function, tmps_base starts off as PL_tmps_floor+1, then increases
3543 * whenever we find or create a temp that we know should be kept. In
3544 * general the stuff above tmps_base is undecided until we reach the end,
3545 * and we may need a sort stage for that.
3546 *
3547 * To determine whether a TEMP is keeping a return arg alive, every
3548 * arg that is kept rather than copied and which has the SvTEMP flag
3549 * set, has the flag temporarily unset, to mark it. At the end we scan
799da9d7 3550 * the temps stack frame above the cut for entries without SvTEMP and
f7a874b8 3551 * keep them, while turning SvTEMP on again. Note that if we die before
799da9d7 3552 * the SvTEMPs flags are set again, its safe: at worst, subsequent use of
f7a874b8
DM
3553 * those SVs may be slightly less efficient.
3554 *
3555 * In practice various optimisations for some common cases mean we can
3556 * avoid most of the scanning and swapping about with the temps stack.
3557 */
3558
799da9d7 3559void
1c23e2bd 3560Perl_leave_adjust_stacks(pTHX_ SV **from_sp, SV **to_sp, U8 gimme, int pass)
a0d0e21e 3561{
263e0548 3562 dVAR;
20b7effb 3563 dSP;
f7a874b8
DM
3564 SSize_t tmps_base; /* lowest index into tmps stack that needs freeing now */
3565 SSize_t nargs;
3566
799da9d7
DM
3567 PERL_ARGS_ASSERT_LEAVE_ADJUST_STACKS;
3568
f7a874b8
DM
3569 TAINT_NOT;
3570
3571 if (gimme == G_ARRAY) {
e02ce34b
DM
3572 nargs = SP - from_sp;
3573 from_sp++;
f7a874b8
DM
3574 }
3575 else {
3576 assert(gimme == G_SCALAR);
e02ce34b 3577 if (UNLIKELY(from_sp >= SP)) {
f7a874b8 3578 /* no return args */
e02ce34b 3579 assert(from_sp == SP);
f7a874b8
DM
3580 EXTEND(SP, 1);
3581 *++SP = &PL_sv_undef;
e02ce34b 3582 to_sp = SP;
f7a874b8
DM
3583 nargs = 0;
3584 }
3585 else {
3586 from_sp = SP;
3587 nargs = 1;
3588 }
3589 }
3590
3591 /* common code for G_SCALAR and G_ARRAY */
3592
3593 tmps_base = PL_tmps_floor + 1;
3594
3595 assert(nargs >= 0);
3596 if (nargs) {
3597 /* pointer version of tmps_base. Not safe across temp stack
3598 * reallocs. */
3599 SV **tmps_basep;
3600
3601 EXTEND_MORTAL(nargs); /* one big extend for worst-case scenario */
3602 tmps_basep = PL_tmps_stack + tmps_base;
f7a874b8
DM
3603
3604 /* process each return arg */
3605
3606 do {
3607 SV *sv = *from_sp++;
3608
3609 assert(PL_tmps_ix + nargs < PL_tmps_max);
3645bb38
DM
3610#ifdef DEBUGGING
3611 /* PADTMPs with container set magic shouldn't appear in the
3612 * wild. This assert is more important for pp_leavesublv(),
3613 * but by testing for it here, we're more likely to catch
3614 * bad cases (what with :lvalue subs not being widely
3615 * deployed). The two issues are that for something like
3616 * sub :lvalue { $tied{foo} }
3617 * or
3618 * sub :lvalue { substr($foo,1,2) }
3619 * pp_leavesublv() will croak if the sub returns a PADTMP,
3620 * and currently functions like pp_substr() return a mortal
3621 * rather than using their PADTMP when returning a PVLV.
3622 * This is because the PVLV will hold a ref to $foo,
3623 * so $foo would get delayed in being freed while
3624 * the PADTMP SV remained in the PAD.
3625 * So if this assert fails it means either:
3626 * 1) there is pp code similar to pp_substr that is
3627 * returning a PADTMP instead of a mortal, and probably
3628 * needs fixing, or
5d9c1c9a 3629 * 2) pp_leavesublv is making unwarranted assumptions
3645bb38
DM
3630 * about always croaking on a PADTMP
3631 */
3632 if (SvPADTMP(sv) && SvSMAGICAL(sv)) {
3633 MAGIC *mg;
3634 for (mg = SvMAGIC(sv); mg; mg = mg->mg_moremagic) {
3635 assert(PERL_MAGIC_TYPE_IS_VALUE_MAGIC(mg->mg_type));
3636 }
3637 }
3638#endif
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