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fix PAD_COMPNAME_GEN documentation
[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"]
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LW
19 */
20
166f8a29
DM
21/* This file contains 'hot' pp ("push/pop") functions that
22 * execute the opcodes that make up a perl program. A typical pp function
23 * expects to find its arguments on the stack, and usually pushes its
24 * results onto the stack, hence the 'pp' terminology. Each OP structure
25 * contains a pointer to the relevant pp_foo() function.
26 *
27 * By 'hot', we mean common ops whose execution speed is critical.
28 * By gathering them together into a single file, we encourage
29 * CPU cache hits on hot code. Also it could be taken as a warning not to
30 * change any code in this file unless you're sure it won't affect
31 * performance.
32 */
33
a0d0e21e 34#include "EXTERN.h"
864dbfa3 35#define PERL_IN_PP_HOT_C
a0d0e21e
LW
36#include "perl.h"
37
38/* Hot code. */
39
40PP(pp_const)
41{
39644a26 42 dSP;
996c9baa 43 XPUSHs(cSVOP_sv);
a0d0e21e
LW
44 RETURN;
45}
46
47PP(pp_nextstate)
48{
533c011a 49 PL_curcop = (COP*)PL_op;
a0d0e21e 50 TAINT_NOT; /* Each statement is presumed innocent */
3280af22 51 PL_stack_sp = PL_stack_base + cxstack[cxstack_ix].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));
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LW
65 RETURN;
66}
67
b1c05ba5
DM
68
69/* also used for: pp_lineseq() pp_regcmaybe() pp_scalar() pp_scope() */
70
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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);
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LW
81 return NORMAL;
82}
83
84PP(pp_stringify)
85{
20b7effb 86 dSP; dTARGET;
4cc783ef
DD
87 SV * const sv = TOPs;
88 SETs(TARG);
89 sv_copypv(TARG, sv);
90 SvSETMAGIC(TARG);
91 /* no PUTBACK, SETs doesn't inc/dec SP */
92 return NORMAL;
a0d0e21e
LW
93}
94
95PP(pp_gv)
96{
20b7effb 97 dSP;
ad64d0ec 98 XPUSHs(MUTABLE_SV(cGVOP_gv));
a0d0e21e
LW
99 RETURN;
100}
101
b1c05ba5
DM
102
103/* also used for: pp_andassign() */
104
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LW
105PP(pp_and)
106{
f410a211 107 PERL_ASYNC_CHECK();
4cc783ef
DD
108 {
109 /* SP is not used to remove a variable that is saved across the
110 sv_2bool_flags call in SvTRUE_NN, if a RISC/CISC or low/high machine
111 register or load/store vs direct mem ops macro is introduced, this
112 should be a define block between direct PL_stack_sp and dSP operations,
113 presently, using PL_stack_sp is bias towards CISC cpus */
114 SV * const sv = *PL_stack_sp;
115 if (!SvTRUE_NN(sv))
116 return NORMAL;
117 else {
118 if (PL_op->op_type == OP_AND)
119 --PL_stack_sp;
120 return cLOGOP->op_other;
121 }
a0d0e21e
LW
122 }
123}
124
125PP(pp_sassign)
126{
20b7effb 127 dSP;
3e75a3c4
RU
128 /* sassign keeps its args in the optree traditionally backwards.
129 So we pop them differently.
130 */
131 SV *left = POPs; SV *right = TOPs;
748a9306 132
533c011a 133 if (PL_op->op_private & OPpASSIGN_BACKWARDS) {
0bd48802
AL
134 SV * const temp = left;
135 left = right; right = temp;
a0d0e21e 136 }
5d9574c1 137 if (TAINTING_get && UNLIKELY(TAINT_get) && !SvTAINTED(right))
a0d0e21e 138 TAINT_NOT;
5d9574c1
DM
139 if (UNLIKELY(PL_op->op_private & OPpASSIGN_CV_TO_GV)) {
140 /* *foo =\&bar */
3e75a3c4 141 SV * const cv = SvRV(right);
e26df76a 142 const U32 cv_type = SvTYPE(cv);
3e75a3c4 143 const bool is_gv = isGV_with_GP(left);
6136c704 144 const bool got_coderef = cv_type == SVt_PVCV || cv_type == SVt_PVFM;
e26df76a
NC
145
146 if (!got_coderef) {
147 assert(SvROK(cv));
148 }
149
3e75a3c4
RU
150 /* Can do the optimisation if left (LVALUE) is not a typeglob,
151 right (RVALUE) is a reference to something, and we're in void
e26df76a 152 context. */
13be902c 153 if (!got_coderef && !is_gv && GIMME_V == G_VOID) {
e26df76a 154 /* Is the target symbol table currently empty? */
3e75a3c4 155 GV * const gv = gv_fetchsv_nomg(left, GV_NOINIT, SVt_PVGV);
bb112e5a 156 if (SvTYPE(gv) != SVt_PVGV && !SvOK(gv)) {
e26df76a
NC
157 /* Good. Create a new proxy constant subroutine in the target.
158 The gv becomes a(nother) reference to the constant. */
159 SV *const value = SvRV(cv);
160
ad64d0ec 161 SvUPGRADE(MUTABLE_SV(gv), SVt_IV);
1ccdb730 162 SvPCS_IMPORTED_on(gv);
e26df76a 163 SvRV_set(gv, value);
b37c2d43 164 SvREFCNT_inc_simple_void(value);
3e75a3c4 165 SETs(left);
e26df76a
NC
166 RETURN;
167 }
168 }
169
170 /* Need to fix things up. */
13be902c 171 if (!is_gv) {
e26df76a 172 /* Need to fix GV. */
3e75a3c4 173 left = MUTABLE_SV(gv_fetchsv_nomg(left,GV_ADD, SVt_PVGV));
e26df76a
NC
174 }
175
176 if (!got_coderef) {
177 /* We've been returned a constant rather than a full subroutine,
178 but they expect a subroutine reference to apply. */
53a42478 179 if (SvROK(cv)) {
d343c3ef 180 ENTER_with_name("sassign_coderef");
53a42478
NC
181 SvREFCNT_inc_void(SvRV(cv));
182 /* newCONSTSUB takes a reference count on the passed in SV
183 from us. We set the name to NULL, otherwise we get into
184 all sorts of fun as the reference to our new sub is
185 donated to the GV that we're about to assign to.
186 */
3e75a3c4 187 SvRV_set(right, MUTABLE_SV(newCONSTSUB(GvSTASH(left), NULL,
ad64d0ec 188 SvRV(cv))));
fc2b2dca 189 SvREFCNT_dec_NN(cv);
d343c3ef 190 LEAVE_with_name("sassign_coderef");
53a42478
NC
191 } else {
192 /* What can happen for the corner case *{"BONK"} = \&{"BONK"};
193 is that
194 First: ops for \&{"BONK"}; return us the constant in the
195 symbol table
196 Second: ops for *{"BONK"} cause that symbol table entry
197 (and our reference to it) to be upgraded from RV
198 to typeblob)
199 Thirdly: We get here. cv is actually PVGV now, and its
200 GvCV() is actually the subroutine we're looking for
201
202 So change the reference so that it points to the subroutine
203 of that typeglob, as that's what they were after all along.
204 */
159b6efe 205 GV *const upgraded = MUTABLE_GV(cv);
53a42478
NC
206 CV *const source = GvCV(upgraded);
207
208 assert(source);
209 assert(CvFLAGS(source) & CVf_CONST);
210
211 SvREFCNT_inc_void(source);
fc2b2dca 212 SvREFCNT_dec_NN(upgraded);
3e75a3c4 213 SvRV_set(right, MUTABLE_SV(source));
53a42478 214 }
e26df76a 215 }
53a42478 216
e26df76a 217 }
8fe85e3f 218 if (
5d9574c1 219 UNLIKELY(SvTEMP(left)) && !SvSMAGICAL(left) && SvREFCNT(left) == 1 &&
3e75a3c4 220 (!isGV_with_GP(left) || SvFAKE(left)) && ckWARN(WARN_MISC)
8fe85e3f
FC
221 )
222 Perl_warner(aTHX_
223 packWARN(WARN_MISC), "Useless assignment to a temporary"
224 );
3e75a3c4
RU
225 SvSetMagicSV(left, right);
226 SETs(left);
a0d0e21e
LW
227 RETURN;
228}
229
230PP(pp_cond_expr)
231{
20b7effb 232 dSP;
f410a211 233 PERL_ASYNC_CHECK();
a0d0e21e 234 if (SvTRUEx(POPs))
1a67a97c 235 RETURNOP(cLOGOP->op_other);
a0d0e21e 236 else
1a67a97c 237 RETURNOP(cLOGOP->op_next);
a0d0e21e
LW
238}
239
240PP(pp_unstack)
241{
8f3964af 242 PERL_ASYNC_CHECK();
a0d0e21e 243 TAINT_NOT; /* Each statement is presumed innocent */
3280af22 244 PL_stack_sp = PL_stack_base + cxstack[cxstack_ix].blk_oldsp;
a0d0e21e 245 FREETMPS;
eae48c89
Z
246 if (!(PL_op->op_flags & OPf_SPECIAL)) {
247 I32 oldsave = PL_scopestack[PL_scopestack_ix - 1];
248 LEAVE_SCOPE(oldsave);
249 }
a0d0e21e
LW
250 return NORMAL;
251}
252
a0d0e21e
LW
253PP(pp_concat)
254{
20b7effb 255 dSP; dATARGET; tryAMAGICbin_MG(concat_amg, AMGf_assign);
748a9306
LW
256 {
257 dPOPTOPssrl;
8d6d96c1
HS
258 bool lbyte;
259 STRLEN rlen;
d4c19fe8 260 const char *rpv = NULL;
a6b599c7 261 bool rbyte = FALSE;
a9c4fd4e 262 bool rcopied = FALSE;
8d6d96c1 263
6f1401dc
DM
264 if (TARG == right && right != left) { /* $r = $l.$r */
265 rpv = SvPV_nomg_const(right, rlen);
c75ab21a 266 rbyte = !DO_UTF8(right);
59cd0e26 267 right = newSVpvn_flags(rpv, rlen, SVs_TEMP);
349d4f2f 268 rpv = SvPV_const(right, rlen); /* no point setting UTF-8 here */
db79b45b 269 rcopied = TRUE;
8d6d96c1 270 }
7889fe52 271
89734059 272 if (TARG != left) { /* not $l .= $r */
a9c4fd4e 273 STRLEN llen;
6f1401dc 274 const char* const lpv = SvPV_nomg_const(left, llen);
90f5826e 275 lbyte = !DO_UTF8(left);
8d6d96c1
HS
276 sv_setpvn(TARG, lpv, llen);
277 if (!lbyte)
278 SvUTF8_on(TARG);
279 else
280 SvUTF8_off(TARG);
281 }
18ea7bf2
SM
282 else { /* $l .= $r and left == TARG */
283 if (!SvOK(left)) {
89734059 284 if (left == right && ckWARN(WARN_UNINITIALIZED)) /* $l .= $l */
c75ab21a 285 report_uninit(right);
76f68e9b 286 sv_setpvs(left, "");
c75ab21a 287 }
18ea7bf2
SM
288 else {
289 SvPV_force_nomg_nolen(left);
290 }
583a5589 291 lbyte = !DO_UTF8(left);
90f5826e 292 if (IN_BYTES)
18ea7bf2 293 SvUTF8_off(left);
8d6d96c1 294 }
a12c0f56 295
c75ab21a 296 if (!rcopied) {
6f1401dc 297 rpv = SvPV_nomg_const(right, rlen);
c75ab21a
RH
298 rbyte = !DO_UTF8(right);
299 }
8d6d96c1
HS
300 if (lbyte != rbyte) {
301 if (lbyte)
302 sv_utf8_upgrade_nomg(TARG);
303 else {
db79b45b 304 if (!rcopied)
59cd0e26 305 right = newSVpvn_flags(rpv, rlen, SVs_TEMP);
8d6d96c1 306 sv_utf8_upgrade_nomg(right);
6f1401dc 307 rpv = SvPV_nomg_const(right, rlen);
69b47968 308 }
a0d0e21e 309 }
8d6d96c1 310 sv_catpvn_nomg(TARG, rpv, rlen);
43ebc500 311
a0d0e21e
LW
312 SETTARG;
313 RETURN;
748a9306 314 }
a0d0e21e
LW
315}
316
d5524600
DM
317/* push the elements of av onto the stack.
318 * XXX Note that padav has similar code but without the mg_get().
319 * I suspect that the mg_get is no longer needed, but while padav
320 * differs, it can't share this function */
321
f9ae8fb6 322STATIC void
d5524600
DM
323S_pushav(pTHX_ AV* const av)
324{
325 dSP;
c70927a6 326 const SSize_t maxarg = AvFILL(av) + 1;
d5524600 327 EXTEND(SP, maxarg);
5d9574c1 328 if (UNLIKELY(SvRMAGICAL(av))) {
c70927a6
FC
329 PADOFFSET i;
330 for (i=0; i < (PADOFFSET)maxarg; i++) {
d5524600
DM
331 SV ** const svp = av_fetch(av, i, FALSE);
332 /* See note in pp_helem, and bug id #27839 */
333 SP[i+1] = svp
334 ? SvGMAGICAL(*svp) ? (mg_get(*svp), *svp) : *svp
335 : &PL_sv_undef;
336 }
337 }
338 else {
c70927a6
FC
339 PADOFFSET i;
340 for (i=0; i < (PADOFFSET)maxarg; i++) {
ce0d59fd 341 SV * const sv = AvARRAY(av)[i];
5d9574c1 342 SP[i+1] = LIKELY(sv) ? sv : &PL_sv_undef;
ce0d59fd 343 }
d5524600
DM
344 }
345 SP += maxarg;
346 PUTBACK;
347}
348
349
a7fd8ef6
DM
350/* ($lex1,@lex2,...) or my ($lex1,@lex2,...) */
351
352PP(pp_padrange)
353{
20b7effb 354 dSP;
a7fd8ef6
DM
355 PADOFFSET base = PL_op->op_targ;
356 int count = (int)(PL_op->op_private) & OPpPADRANGE_COUNTMASK;
357 int i;
d5524600
DM
358 if (PL_op->op_flags & OPf_SPECIAL) {
359 /* fake the RHS of my ($x,$y,..) = @_ */
360 PUSHMARK(SP);
361 S_pushav(aTHX_ GvAVn(PL_defgv));
362 SPAGAIN;
363 }
364
a7fd8ef6
DM
365 /* note, this is only skipped for compile-time-known void cxt */
366 if ((PL_op->op_flags & OPf_WANT) != OPf_WANT_VOID) {
367 EXTEND(SP, count);
368 PUSHMARK(SP);
369 for (i = 0; i <count; i++)
370 *++SP = PAD_SV(base+i);
371 }
372 if (PL_op->op_private & OPpLVAL_INTRO) {
4e09461c
DM
373 SV **svp = &(PAD_SVl(base));
374 const UV payload = (UV)(
375 (base << (OPpPADRANGE_COUNTSHIFT + SAVE_TIGHT_SHIFT))
376 | (count << SAVE_TIGHT_SHIFT)
377 | SAVEt_CLEARPADRANGE);
6d59e610 378 STATIC_ASSERT_STMT(OPpPADRANGE_COUNTMASK + 1 == (1 << OPpPADRANGE_COUNTSHIFT));
4e09461c 379 assert((payload >> (OPpPADRANGE_COUNTSHIFT+SAVE_TIGHT_SHIFT)) == base);
a3444cc5
DM
380 {
381 dSS_ADD;
382 SS_ADD_UV(payload);
383 SS_ADD_END(1);
384 }
4e09461c 385
a7fd8ef6 386 for (i = 0; i <count; i++)
4e09461c 387 SvPADSTALE_off(*svp++); /* mark lexical as active */
a7fd8ef6
DM
388 }
389 RETURN;
390}
391
392
a0d0e21e
LW
393PP(pp_padsv)
394{
20b7effb 395 dSP;
6c28b496
DD
396 EXTEND(SP, 1);
397 {
398 OP * const op = PL_op;
399 /* access PL_curpad once */
400 SV ** const padentry = &(PAD_SVl(op->op_targ));
401 {
402 dTARG;
403 TARG = *padentry;
404 PUSHs(TARG);
405 PUTBACK; /* no pop/push after this, TOPs ok */
8ec5e241 406 }
6c28b496
DD
407 if (op->op_flags & OPf_MOD) {
408 if (op->op_private & OPpLVAL_INTRO)
409 if (!(op->op_private & OPpPAD_STATE))
410 save_clearsv(padentry);
411 if (op->op_private & OPpDEREF) {
8f90a16d
FC
412 /* TOPs is equivalent to TARG here. Using TOPs (SP) rather
413 than TARG reduces the scope of TARG, so it does not
414 span the call to save_clearsv, resulting in smaller
415 machine code. */
6c28b496
DD
416 TOPs = vivify_ref(TOPs, op->op_private & OPpDEREF);
417 }
418 }
419 return op->op_next;
4633a7c4 420 }
a0d0e21e
LW
421}
422
423PP(pp_readline)
424{
30901a8a
FC
425 dSP;
426 if (TOPs) {
427 SvGETMAGIC(TOPs);
fc99edcf 428 tryAMAGICunTARGETlist(iter_amg, 0);
30901a8a
FC
429 PL_last_in_gv = MUTABLE_GV(*PL_stack_sp--);
430 }
431 else PL_last_in_gv = PL_argvgv, PL_stack_sp--;
6e592b3a
BM
432 if (!isGV_with_GP(PL_last_in_gv)) {
433 if (SvROK(PL_last_in_gv) && isGV_with_GP(SvRV(PL_last_in_gv)))
159b6efe 434 PL_last_in_gv = MUTABLE_GV(SvRV(PL_last_in_gv));
8efb3254 435 else {
f5284f61 436 dSP;
ad64d0ec 437 XPUSHs(MUTABLE_SV(PL_last_in_gv));
f5284f61 438 PUTBACK;
897d3989 439 Perl_pp_rv2gv(aTHX);
159b6efe 440 PL_last_in_gv = MUTABLE_GV(*PL_stack_sp--);
84ee769f
FC
441 if (PL_last_in_gv == (GV *)&PL_sv_undef)
442 PL_last_in_gv = NULL;
443 else
444 assert(isGV_with_GP(PL_last_in_gv));
f5284f61
IZ
445 }
446 }
a0d0e21e
LW
447 return do_readline();
448}
449
450PP(pp_eq)
451{
20b7effb 452 dSP;
33efebe6
DM
453 SV *left, *right;
454
a42d0242 455 tryAMAGICbin_MG(eq_amg, AMGf_set|AMGf_numeric);
33efebe6
DM
456 right = POPs;
457 left = TOPs;
458 SETs(boolSV(
459 (SvIOK_notUV(left) && SvIOK_notUV(right))
460 ? (SvIVX(left) == SvIVX(right))
461 : ( do_ncmp(left, right) == 0)
462 ));
463 RETURN;
a0d0e21e
LW
464}
465
b1c05ba5
DM
466
467/* also used for: pp_i_predec() pp_i_preinc() pp_predec() */
468
a0d0e21e
LW
469PP(pp_preinc)
470{
20b7effb 471 dSP;
17058fe0
FC
472 const bool inc =
473 PL_op->op_type == OP_PREINC || PL_op->op_type == OP_I_PREINC;
5d9574c1 474 if (UNLIKELY(SvTYPE(TOPs) >= SVt_PVAV || (isGV_with_GP(TOPs) && !SvFAKE(TOPs))))
cb077ed2 475 Perl_croak_no_modify();
5d9574c1 476 if (LIKELY(!SvREADONLY(TOPs) && !SvGMAGICAL(TOPs) && SvIOK_notUV(TOPs) && !SvNOK(TOPs) && !SvPOK(TOPs))
17058fe0 477 && SvIVX(TOPs) != (inc ? IV_MAX : IV_MIN))
55497cff 478 {
17058fe0 479 SvIV_set(TOPs, SvIVX(TOPs) + (inc ? 1 : -1));
55497cff 480 SvFLAGS(TOPs) &= ~(SVp_NOK|SVp_POK);
748a9306 481 }
28e5dec8 482 else /* Do all the PERL_PRESERVE_IVUV conditionals in sv_inc */
17058fe0
FC
483 if (inc) sv_inc(TOPs);
484 else sv_dec(TOPs);
a0d0e21e
LW
485 SvSETMAGIC(TOPs);
486 return NORMAL;
487}
488
b1c05ba5
DM
489
490/* also used for: pp_orassign() */
491
a0d0e21e
LW
492PP(pp_or)
493{
20b7effb 494 dSP;
f410a211 495 PERL_ASYNC_CHECK();
a0d0e21e
LW
496 if (SvTRUE(TOPs))
497 RETURN;
498 else {
c960fc3b
SP
499 if (PL_op->op_type == OP_OR)
500 --SP;
a0d0e21e
LW
501 RETURNOP(cLOGOP->op_other);
502 }
503}
504
b1c05ba5
DM
505
506/* also used for: pp_dor() pp_dorassign() */
507
25a55bd7 508PP(pp_defined)
c963b151 509{
20b7effb 510 dSP;
eb578fdb 511 SV* sv;
6136c704 512 bool defined;
25a55bd7 513 const int op_type = PL_op->op_type;
ea5195b7 514 const bool is_dor = (op_type == OP_DOR || op_type == OP_DORASSIGN);
c963b151 515
6136c704 516 if (is_dor) {
f410a211 517 PERL_ASYNC_CHECK();
25a55bd7 518 sv = TOPs;
5d9574c1 519 if (UNLIKELY(!sv || !SvANY(sv))) {
2bd49cfc
NC
520 if (op_type == OP_DOR)
521 --SP;
25a55bd7
SP
522 RETURNOP(cLOGOP->op_other);
523 }
b7c44293
RGS
524 }
525 else {
526 /* OP_DEFINED */
25a55bd7 527 sv = POPs;
5d9574c1 528 if (UNLIKELY(!sv || !SvANY(sv)))
25a55bd7 529 RETPUSHNO;
b7c44293 530 }
25a55bd7 531
6136c704 532 defined = FALSE;
c963b151
BD
533 switch (SvTYPE(sv)) {
534 case SVt_PVAV:
535 if (AvMAX(sv) >= 0 || SvGMAGICAL(sv) || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
25a55bd7 536 defined = TRUE;
c963b151
BD
537 break;
538 case SVt_PVHV:
539 if (HvARRAY(sv) || SvGMAGICAL(sv) || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
25a55bd7 540 defined = TRUE;
c963b151
BD
541 break;
542 case SVt_PVCV:
543 if (CvROOT(sv) || CvXSUB(sv))
25a55bd7 544 defined = TRUE;
c963b151
BD
545 break;
546 default:
5b295bef 547 SvGETMAGIC(sv);
c963b151 548 if (SvOK(sv))
25a55bd7 549 defined = TRUE;
6136c704 550 break;
c963b151 551 }
6136c704
AL
552
553 if (is_dor) {
c960fc3b
SP
554 if(defined)
555 RETURN;
556 if(op_type == OP_DOR)
557 --SP;
25a55bd7 558 RETURNOP(cLOGOP->op_other);
25a55bd7 559 }
d9aa96a4
SP
560 /* assuming OP_DEFINED */
561 if(defined)
562 RETPUSHYES;
563 RETPUSHNO;
c963b151
BD
564}
565
a0d0e21e
LW
566PP(pp_add)
567{
20b7effb 568 dSP; dATARGET; bool useleft; SV *svl, *svr;
6f1401dc
DM
569 tryAMAGICbin_MG(add_amg, AMGf_assign|AMGf_numeric);
570 svr = TOPs;
571 svl = TOPm1s;
572
800401ee 573 useleft = USE_LEFT(svl);
28e5dec8
JH
574#ifdef PERL_PRESERVE_IVUV
575 /* We must see if we can perform the addition with integers if possible,
576 as the integer code detects overflow while the NV code doesn't.
577 If either argument hasn't had a numeric conversion yet attempt to get
578 the IV. It's important to do this now, rather than just assuming that
579 it's not IOK as a PV of "9223372036854775806" may not take well to NV
580 addition, and an SV which is NOK, NV=6.0 ought to be coerced to
581 integer in case the second argument is IV=9223372036854775806
582 We can (now) rely on sv_2iv to do the right thing, only setting the
583 public IOK flag if the value in the NV (or PV) slot is truly integer.
584
585 A side effect is that this also aggressively prefers integer maths over
7dca457a
NC
586 fp maths for integer values.
587
a00b5bd3 588 How to detect overflow?
7dca457a
NC
589
590 C 99 section 6.2.6.1 says
591
592 The range of nonnegative values of a signed integer type is a subrange
593 of the corresponding unsigned integer type, and the representation of
594 the same value in each type is the same. A computation involving
595 unsigned operands can never overflow, because a result that cannot be
596 represented by the resulting unsigned integer type is reduced modulo
597 the number that is one greater than the largest value that can be
598 represented by the resulting type.
599
600 (the 9th paragraph)
601
602 which I read as "unsigned ints wrap."
603
604 signed integer overflow seems to be classed as "exception condition"
605
606 If an exceptional condition occurs during the evaluation of an
607 expression (that is, if the result is not mathematically defined or not
608 in the range of representable values for its type), the behavior is
609 undefined.
610
611 (6.5, the 5th paragraph)
612
613 I had assumed that on 2s complement machines signed arithmetic would
614 wrap, hence coded pp_add and pp_subtract on the assumption that
615 everything perl builds on would be happy. After much wailing and
616 gnashing of teeth it would seem that irix64 knows its ANSI spec well,
617 knows that it doesn't need to, and doesn't. Bah. Anyway, the all-
618 unsigned code below is actually shorter than the old code. :-)
619 */
620
01f91bf2 621 if (SvIV_please_nomg(svr)) {
28e5dec8
JH
622 /* Unless the left argument is integer in range we are going to have to
623 use NV maths. Hence only attempt to coerce the right argument if
624 we know the left is integer. */
eb578fdb 625 UV auv = 0;
9c5ffd7c 626 bool auvok = FALSE;
7dca457a
NC
627 bool a_valid = 0;
628
28e5dec8 629 if (!useleft) {
7dca457a
NC
630 auv = 0;
631 a_valid = auvok = 1;
632 /* left operand is undef, treat as zero. + 0 is identity,
633 Could SETi or SETu right now, but space optimise by not adding
634 lots of code to speed up what is probably a rarish case. */
635 } else {
636 /* Left operand is defined, so is it IV? */
01f91bf2 637 if (SvIV_please_nomg(svl)) {
800401ee
JH
638 if ((auvok = SvUOK(svl)))
639 auv = SvUVX(svl);
7dca457a 640 else {
eb578fdb 641 const IV aiv = SvIVX(svl);
7dca457a
NC
642 if (aiv >= 0) {
643 auv = aiv;
644 auvok = 1; /* Now acting as a sign flag. */
53e2bfb7
DM
645 } else {
646 auv = (aiv == IV_MIN) ? (UV)aiv : (UV)(-aiv);
7dca457a
NC
647 }
648 }
649 a_valid = 1;
28e5dec8
JH
650 }
651 }
7dca457a
NC
652 if (a_valid) {
653 bool result_good = 0;
654 UV result;
eb578fdb 655 UV buv;
800401ee 656 bool buvok = SvUOK(svr);
a00b5bd3 657
7dca457a 658 if (buvok)
800401ee 659 buv = SvUVX(svr);
7dca457a 660 else {
eb578fdb 661 const IV biv = SvIVX(svr);
7dca457a
NC
662 if (biv >= 0) {
663 buv = biv;
664 buvok = 1;
665 } else
53e2bfb7 666 buv = (biv == IV_MIN) ? (UV)biv : (UV)(-biv);
7dca457a
NC
667 }
668 /* ?uvok if value is >= 0. basically, flagged as UV if it's +ve,
602f51c4 669 else "IV" now, independent of how it came in.
7dca457a
NC
670 if a, b represents positive, A, B negative, a maps to -A etc
671 a + b => (a + b)
672 A + b => -(a - b)
673 a + B => (a - b)
674 A + B => -(a + b)
675 all UV maths. negate result if A negative.
676 add if signs same, subtract if signs differ. */
677
678 if (auvok ^ buvok) {
679 /* Signs differ. */
680 if (auv >= buv) {
681 result = auv - buv;
682 /* Must get smaller */
683 if (result <= auv)
684 result_good = 1;
685 } else {
686 result = buv - auv;
687 if (result <= buv) {
688 /* result really should be -(auv-buv). as its negation
689 of true value, need to swap our result flag */
690 auvok = !auvok;
691 result_good = 1;
28e5dec8
JH
692 }
693 }
7dca457a
NC
694 } else {
695 /* Signs same */
696 result = auv + buv;
697 if (result >= auv)
698 result_good = 1;
699 }
700 if (result_good) {
701 SP--;
702 if (auvok)
28e5dec8 703 SETu( result );
7dca457a
NC
704 else {
705 /* Negate result */
706 if (result <= (UV)IV_MIN)
53e2bfb7
DM
707 SETi(result == (UV)IV_MIN
708 ? IV_MIN : -(IV)result);
7dca457a
NC
709 else {
710 /* result valid, but out of range for IV. */
711 SETn( -(NV)result );
28e5dec8
JH
712 }
713 }
7dca457a
NC
714 RETURN;
715 } /* Overflow, drop through to NVs. */
28e5dec8
JH
716 }
717 }
718#endif
a0d0e21e 719 {
6f1401dc 720 NV value = SvNV_nomg(svr);
4efa5a16 721 (void)POPs;
28e5dec8
JH
722 if (!useleft) {
723 /* left operand is undef, treat as zero. + 0.0 is identity. */
724 SETn(value);
725 RETURN;
726 }
6f1401dc 727 SETn( value + SvNV_nomg(svl) );
28e5dec8 728 RETURN;
a0d0e21e
LW
729 }
730}
731
b1c05ba5
DM
732
733/* also used for: pp_aelemfast_lex() */
734
a0d0e21e
LW
735PP(pp_aelemfast)
736{
20b7effb 737 dSP;
93bad3fd 738 AV * const av = PL_op->op_type == OP_AELEMFAST_LEX
8f878375 739 ? MUTABLE_AV(PAD_SV(PL_op->op_targ)) : GvAVn(cGVOP_gv);
a3b680e6 740 const U32 lval = PL_op->op_flags & OPf_MOD;
b024352e 741 SV** const svp = av_fetch(av, (I8)PL_op->op_private, lval);
3280af22 742 SV *sv = (svp ? *svp : &PL_sv_undef);
b024352e
DM
743
744 if (UNLIKELY(!svp && lval))
745 DIE(aTHX_ PL_no_aelem, (int)(I8)PL_op->op_private);
746
6ff81951 747 EXTEND(SP, 1);
39cf747a 748 if (!lval && SvRMAGICAL(av) && SvGMAGICAL(sv)) /* see note in pp_helem() */
fd69380d 749 mg_get(sv);
be6c24e0 750 PUSHs(sv);
a0d0e21e
LW
751 RETURN;
752}
753
754PP(pp_join)
755{
20b7effb 756 dSP; dMARK; dTARGET;
a0d0e21e
LW
757 MARK++;
758 do_join(TARG, *MARK, MARK, SP);
759 SP = MARK;
760 SETs(TARG);
761 RETURN;
762}
763
764PP(pp_pushre)
765{
20b7effb 766 dSP;
44a8e56a
PP
767#ifdef DEBUGGING
768 /*
769 * We ass_u_me that LvTARGOFF() comes first, and that two STRLENs
770 * will be enough to hold an OP*.
771 */
c4420975 772 SV* const sv = sv_newmortal();
44a8e56a
PP
773 sv_upgrade(sv, SVt_PVLV);
774 LvTYPE(sv) = '/';
533c011a 775 Copy(&PL_op, &LvTARGOFF(sv), 1, OP*);
44a8e56a
PP
776 XPUSHs(sv);
777#else
ad64d0ec 778 XPUSHs(MUTABLE_SV(PL_op));
44a8e56a 779#endif
a0d0e21e
LW
780 RETURN;
781}
782
783/* Oversized hot code. */
784
b1c05ba5
DM
785/* also used for: pp_say() */
786
a0d0e21e
LW
787PP(pp_print)
788{
20b7effb 789 dSP; dMARK; dORIGMARK;
eb578fdb 790 PerlIO *fp;
236988e4 791 MAGIC *mg;
159b6efe
NC
792 GV * const gv
793 = (PL_op->op_flags & OPf_STACKED) ? MUTABLE_GV(*++MARK) : PL_defoutgv;
9c9f25b8 794 IO *io = GvIO(gv);
5b468f54 795
9c9f25b8 796 if (io
ad64d0ec 797 && (mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar)))
5b468f54 798 {
01bb7c6d 799 had_magic:
68dc0745 800 if (MARK == ORIGMARK) {
1c846c1f 801 /* If using default handle then we need to make space to
a60c0954
NIS
802 * pass object as 1st arg, so move other args up ...
803 */
4352c267 804 MEXTEND(SP, 1);
68dc0745
PP
805 ++MARK;
806 Move(MARK, MARK + 1, (SP - MARK) + 1, SV*);
807 ++SP;
808 }
3e0cb5de 809 return Perl_tied_method(aTHX_ SV_CONST(PRINT), mark - 1, MUTABLE_SV(io),
94bc412f
NC
810 mg,
811 (G_SCALAR | TIED_METHOD_ARGUMENTS_ON_STACK
812 | (PL_op->op_type == OP_SAY
813 ? TIED_METHOD_SAY : 0)), sp - mark);
236988e4 814 }
9c9f25b8 815 if (!io) {
68b590d9 816 if ( gv && GvEGVx(gv) && (io = GvIO(GvEGV(gv)))
ad64d0ec 817 && (mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar)))
01bb7c6d 818 goto had_magic;
51087808 819 report_evil_fh(gv);
93189314 820 SETERRNO(EBADF,RMS_IFI);
a0d0e21e
LW
821 goto just_say_no;
822 }
823 else if (!(fp = IoOFP(io))) {
7716c5c5
NC
824 if (IoIFP(io))
825 report_wrongway_fh(gv, '<');
51087808 826 else
7716c5c5 827 report_evil_fh(gv);
93189314 828 SETERRNO(EBADF,IoIFP(io)?RMS_FAC:RMS_IFI);
a0d0e21e
LW
829 goto just_say_no;
830 }
831 else {
e23d9e2f 832 SV * const ofs = GvSV(PL_ofsgv); /* $, */
a0d0e21e 833 MARK++;
e23d9e2f 834 if (ofs && (SvGMAGICAL(ofs) || SvOK(ofs))) {
a0d0e21e
LW
835 while (MARK <= SP) {
836 if (!do_print(*MARK, fp))
837 break;
838 MARK++;
839 if (MARK <= SP) {
e23d9e2f
CS
840 /* don't use 'ofs' here - it may be invalidated by magic callbacks */
841 if (!do_print(GvSV(PL_ofsgv), fp)) {
a0d0e21e
LW
842 MARK--;
843 break;
844 }
845 }
846 }
847 }
848 else {
849 while (MARK <= SP) {
850 if (!do_print(*MARK, fp))
851 break;
852 MARK++;
853 }
854 }
855 if (MARK <= SP)
856 goto just_say_no;
857 else {
cfc4a7da
GA
858 if (PL_op->op_type == OP_SAY) {
859 if (PerlIO_write(fp, "\n", 1) == 0 || PerlIO_error(fp))
860 goto just_say_no;
861 }
862 else if (PL_ors_sv && SvOK(PL_ors_sv))
7889fe52 863 if (!do_print(PL_ors_sv, fp)) /* $\ */
a0d0e21e
LW
864 goto just_say_no;
865
866 if (IoFLAGS(io) & IOf_FLUSH)
760ac839 867 if (PerlIO_flush(fp) == EOF)
a0d0e21e
LW
868 goto just_say_no;
869 }
870 }
871 SP = ORIGMARK;
e52fd6f4 872 XPUSHs(&PL_sv_yes);
a0d0e21e
LW
873 RETURN;
874
875 just_say_no:
876 SP = ORIGMARK;
e52fd6f4 877 XPUSHs(&PL_sv_undef);
a0d0e21e
LW
878 RETURN;
879}
880
b1c05ba5
DM
881
882/* also used for: pp_rv2hv() */
bdaf10a5 883/* also called directly by pp_lvavref */
b1c05ba5 884
a0d0e21e
LW
885PP(pp_rv2av)
886{
20b7effb 887 dSP; dTOPss;
cde874ca 888 const I32 gimme = GIMME_V;
13c59d41
MH
889 static const char an_array[] = "an ARRAY";
890 static const char a_hash[] = "a HASH";
bdaf10a5
FC
891 const bool is_pp_rv2av = PL_op->op_type == OP_RV2AV
892 || PL_op->op_type == OP_LVAVREF;
d83b45b8 893 const svtype type = is_pp_rv2av ? SVt_PVAV : SVt_PVHV;
a0d0e21e 894
9026059d 895 SvGETMAGIC(sv);
a0d0e21e 896 if (SvROK(sv)) {
5d9574c1 897 if (UNLIKELY(SvAMAGIC(sv))) {
93d7320b 898 sv = amagic_deref_call(sv, is_pp_rv2av ? to_av_amg : to_hv_amg);
93d7320b 899 }
17ab7946 900 sv = SvRV(sv);
5d9574c1 901 if (UNLIKELY(SvTYPE(sv) != type))
dcbac5bb 902 /* diag_listed_as: Not an ARRAY reference */
13c59d41 903 DIE(aTHX_ "Not %s reference", is_pp_rv2av ? an_array : a_hash);
5d9574c1
DM
904 else if (UNLIKELY(PL_op->op_flags & OPf_MOD
905 && PL_op->op_private & OPpLVAL_INTRO))
3da99855 906 Perl_croak(aTHX_ "%s", PL_no_localize_ref);
a0d0e21e 907 }
5d9574c1 908 else if (UNLIKELY(SvTYPE(sv) != type)) {
67955e0c 909 GV *gv;
1c846c1f 910
6e592b3a 911 if (!isGV_with_GP(sv)) {
13c59d41 912 gv = Perl_softref2xv(aTHX_ sv, is_pp_rv2av ? an_array : a_hash,
dc3c76f8
NC
913 type, &sp);
914 if (!gv)
915 RETURN;
35cd451c
GS
916 }
917 else {
159b6efe 918 gv = MUTABLE_GV(sv);
a0d0e21e 919 }
ad64d0ec 920 sv = is_pp_rv2av ? MUTABLE_SV(GvAVn(gv)) : MUTABLE_SV(GvHVn(gv));
533c011a 921 if (PL_op->op_private & OPpLVAL_INTRO)
ad64d0ec 922 sv = is_pp_rv2av ? MUTABLE_SV(save_ary(gv)) : MUTABLE_SV(save_hash(gv));
9f527363
FC
923 }
924 if (PL_op->op_flags & OPf_REF) {
17ab7946 925 SETs(sv);
a0d0e21e 926 RETURN;
9f527363 927 }
5d9574c1 928 else if (UNLIKELY(PL_op->op_private & OPpMAYBE_LVSUB)) {
40c94d11
FC
929 const I32 flags = is_lvalue_sub();
930 if (flags && !(flags & OPpENTERSUB_INARGS)) {
cde874ca 931 if (gimme != G_ARRAY)
042560a6 932 goto croak_cant_return;
17ab7946 933 SETs(sv);
78f9721b 934 RETURN;
40c94d11 935 }
a0d0e21e
LW
936 }
937
17ab7946 938 if (is_pp_rv2av) {
502c6561 939 AV *const av = MUTABLE_AV(sv);
636fe681 940 /* The guts of pp_rv2av */
96913b52 941 if (gimme == G_ARRAY) {
d5524600
DM
942 SP--;
943 PUTBACK;
944 S_pushav(aTHX_ av);
945 SPAGAIN;
1c846c1f 946 }
96913b52
VP
947 else if (gimme == G_SCALAR) {
948 dTARGET;
c70927a6 949 const SSize_t maxarg = AvFILL(av) + 1;
96913b52 950 SETi(maxarg);
93965878 951 }
17ab7946
NC
952 } else {
953 /* The guts of pp_rv2hv */
96913b52
VP
954 if (gimme == G_ARRAY) { /* array wanted */
955 *PL_stack_sp = sv;
981b7185 956 return Perl_do_kv(aTHX);
96913b52 957 }
c8fe3bdf 958 else if ((PL_op->op_private & OPpTRUEBOOL
adc42c31 959 || ( PL_op->op_private & OPpMAYBE_TRUEBOOL
c8fe3bdf
FC
960 && block_gimme() == G_VOID ))
961 && (!SvRMAGICAL(sv) || !mg_find(sv, PERL_MAGIC_tied)))
962 SETs(HvUSEDKEYS(sv) ? &PL_sv_yes : sv_2mortal(newSViv(0)));
96913b52 963 else if (gimme == G_SCALAR) {
1a8bdda9 964 dTARG;
96913b52 965 TARG = Perl_hv_scalar(aTHX_ MUTABLE_HV(sv));
96913b52
VP
966 SETTARG;
967 }
17ab7946 968 }
be85d344 969 RETURN;
042560a6
NC
970
971 croak_cant_return:
972 Perl_croak(aTHX_ "Can't return %s to lvalue scalar context",
973 is_pp_rv2av ? "array" : "hash");
77e217c6 974 RETURN;
a0d0e21e
LW
975}
976
10c8fecd 977STATIC void
fb8f4cf8 978S_do_oddball(pTHX_ SV **oddkey, SV **firstkey)
10c8fecd 979{
7918f24d
NC
980 PERL_ARGS_ASSERT_DO_ODDBALL;
981
fb8f4cf8 982 if (*oddkey) {
6d822dc4 983 if (ckWARN(WARN_MISC)) {
a3b680e6 984 const char *err;
fb8f4cf8
RZ
985 if (oddkey == firstkey &&
986 SvROK(*oddkey) &&
987 (SvTYPE(SvRV(*oddkey)) == SVt_PVAV ||
988 SvTYPE(SvRV(*oddkey)) == SVt_PVHV))
10c8fecd 989 {
a3b680e6 990 err = "Reference found where even-sized list expected";
10c8fecd
GS
991 }
992 else
a3b680e6 993 err = "Odd number of elements in hash assignment";
f1f66076 994 Perl_warner(aTHX_ packWARN(WARN_MISC), "%s", err);
10c8fecd 995 }
6d822dc4 996
10c8fecd
GS
997 }
998}
999
a5f48505
DM
1000
1001/* Do a mark and sweep with the SVf_BREAK flag to detect elements which
1002 * are common to both the LHS and RHS of an aassign, and replace them
1003 * with copies. All these copies are made before the actual list assign is
1004 * done.
1005 *
1006 * For example in ($a,$b) = ($b,$a), assigning the value of the first RHS
1007 * element ($b) to the first LH element ($a), modifies $a; when the
1008 * second assignment is done, the second RH element now has the wrong
1009 * value. So we initially replace the RHS with ($b, mortalcopy($a)).
1010 * Note that we don't need to make a mortal copy of $b.
1011 *
1012 * The algorithm below works by, for every RHS element, mark the
1013 * corresponding LHS target element with SVf_BREAK. Then if the RHS
1014 * element is found with SVf_BREAK set, it means it would have been
1015 * modified, so make a copy.
1016 * Note that by scanning both LHS and RHS in lockstep, we avoid
1017 * unnecessary copies (like $b above) compared with a naive
1018 * "mark all LHS; copy all marked RHS; unmark all LHS".
1019 *
1020 * If the LHS element is a 'my' declaration' and has a refcount of 1, then
1021 * it can't be common and can be skipped.
1022 */
1023
1024PERL_STATIC_INLINE void
1025S_aassign_copy_common(pTHX_ SV **firstlelem, SV **lastlelem,
1026 SV **firstrelem, SV **lastrelem)
1027{
1028 dVAR;
1029 SV **relem;
1030 SV **lelem;
1031 SSize_t lcount = lastlelem - firstlelem + 1;
1032 bool marked = FALSE; /* have we marked any LHS with SVf_BREAK ? */
1033 bool const do_rc1 = cBOOL(PL_op->op_private & OPpASSIGN_COMMON_RC1);
1034
1035 assert(!PL_in_clean_all); /* SVf_BREAK not already in use */
1036 assert(firstlelem < lastlelem); /* at least 2 LH elements */
1037 assert(firstrelem < lastrelem); /* at least 2 RH elements */
1038
1039 /* we never have to copy the first RH element; it can't be corrupted
1040 * by assigning something to the corresponding first LH element.
1041 * So this scan does in a loop: mark LHS[N]; test RHS[N+1]
1042 */
1043 firstrelem++;
1044
1045 lelem = firstlelem;
1046 relem = firstrelem;
1047
1048 for (; relem <= lastrelem; relem++) {
1049 SV *svr;
1050
1051 /* mark next LH element */
1052
1053 if (--lcount >= 0) {
1054 SV *svl = *lelem++;
1055
1056 if (UNLIKELY(!svl)) {/* skip AV alias marker */
1057 assert (lelem <= lastlelem);
1058 svl = *lelem++;
1059 lcount--;
1060 }
1061
1062 assert(svl);
1063 if (SvTYPE(svl) == SVt_PVAV || SvTYPE(svl) == SVt_PVHV) {
1064 if (!marked)
1065 return;
1066 /* this LH element will consume all further args;
1067 * no need to mark any further LH elements (if any).
1068 * But we still need to scan any remaining RHS elements;
1069 * set lcount negative to distinguish from lcount == 0,
1070 * so the loop condition continues being true
1071 */
1072 lcount = -1;
1073 lelem--; /* no need to unmark this element */
1074 }
1075 else if (!(do_rc1 && SvREFCNT(svl) == 1) && svl != &PL_sv_undef) {
1076 assert(!SvIMMORTAL(svl));
1077 SvFLAGS(svl) |= SVf_BREAK;
1078 marked = TRUE;
1079 }
1080 else if (!marked) {
1081 /* don't check RH element if no SVf_BREAK flags set yet */
1082 if (!lcount)
1083 break;
1084 continue;
1085 }
1086 }
1087
1088 /* see if corresponding RH element needs copying */
1089
1090 assert(marked);
1091 svr = *relem;
1092 assert(svr);
1093
1094 if (UNLIKELY(SvFLAGS(svr) & SVf_BREAK)) {
1095
1096 TAINT_NOT; /* Each item is independent */
1097
1098 /* Dear TODO test in t/op/sort.t, I love you.
1099 (It's relying on a panic, not a "semi-panic" from newSVsv()
1100 and then an assertion failure below.) */
1101 if (UNLIKELY(SvIS_FREED(svr))) {
1102 Perl_croak(aTHX_ "panic: attempt to copy freed scalar %p",
1103 (void*)svr);
1104 }
1105 /* avoid break flag while copying; otherwise COW etc
1106 * disabled... */
1107 SvFLAGS(svr) &= ~SVf_BREAK;
1108 /* Not newSVsv(), as it does not allow copy-on-write,
1109 resulting in wasteful copies. We need a second copy of
1110 a temp here, hence the SV_NOSTEAL. */
1111 *relem = sv_mortalcopy_flags(svr,
1112 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
1113 /* ... but restore afterwards in case it's needed again,
1114 * e.g. ($a,$b,$c) = (1,$a,$a)
1115 */
1116 SvFLAGS(svr) |= SVf_BREAK;
1117 }
1118
1119 if (!lcount)
1120 break;
1121 }
1122
1123 if (!marked)
1124 return;
1125
1126 /*unmark LHS */
1127
1128 while (lelem > firstlelem) {
1129 SV * const svl = *(--lelem);
1130 if (svl)
1131 SvFLAGS(svl) &= ~SVf_BREAK;
1132 }
1133}
1134
1135
1136
a0d0e21e
LW
1137PP(pp_aassign)
1138{
27da23d5 1139 dVAR; dSP;
3280af22
NIS
1140 SV **lastlelem = PL_stack_sp;
1141 SV **lastrelem = PL_stack_base + POPMARK;
1142 SV **firstrelem = PL_stack_base + POPMARK + 1;
a0d0e21e
LW
1143 SV **firstlelem = lastrelem + 1;
1144
eb578fdb
KW
1145 SV **relem;
1146 SV **lelem;
a0d0e21e 1147
eb578fdb
KW
1148 SV *sv;
1149 AV *ary;
a0d0e21e 1150
54310121 1151 I32 gimme;
a0d0e21e 1152 HV *hash;
c70927a6 1153 SSize_t i;
a0d0e21e 1154 int magic;
a5f48505 1155 U32 lval;
5637b936 1156
3280af22 1157 PL_delaymagic = DM_DELAY; /* catch simultaneous items */
a0d0e21e
LW
1158
1159 /* If there's a common identifier on both sides we have to take
1160 * special care that assigning the identifier on the left doesn't
1161 * clobber a value on the right that's used later in the list.
1162 */
acdea6f0 1163
a5f48505
DM
1164 if ( (PL_op->op_private & (OPpASSIGN_COMMON_SCALAR|OPpASSIGN_COMMON_RC1))
1165 /* at least 2 LH and RH elements, or commonality isn't an issue */
1166 && (firstlelem < lastlelem && firstrelem < lastrelem)
acdea6f0 1167 ) {
a5f48505
DM
1168 if (PL_op->op_private & OPpASSIGN_COMMON_RC1) {
1169 /* skip the scan if all scalars have a ref count of 1 */
1170 for (lelem = firstlelem; lelem <= lastlelem; lelem++) {
1171 sv = *lelem;
1172 if (!sv || SvREFCNT(sv) == 1)
1173 continue;
1174 if (SvTYPE(sv) != SVt_PVAV && SvTYPE(sv) != SVt_PVAV)
1175 goto do_scan;
1176 break;
1177 }
1178 }
1179 else {
1180 do_scan:
1181 S_aassign_copy_common(aTHX_
1182 firstlelem, lastlelem, firstrelem, lastrelem);
1183 }
a0d0e21e
LW
1184 }
1185
a5f48505
DM
1186 gimme = GIMME_V;
1187 lval = (gimme == G_ARRAY) ? (PL_op->op_flags & OPf_MOD || LVRET) : 0;
1188
a0d0e21e
LW
1189 relem = firstrelem;
1190 lelem = firstlelem;
4608196e
RGS
1191 ary = NULL;
1192 hash = NULL;
10c8fecd 1193
5d9574c1 1194 while (LIKELY(lelem <= lastlelem)) {
bdaf10a5 1195 bool alias = FALSE;
bbce6d69 1196 TAINT_NOT; /* Each item stands on its own, taintwise. */
a0d0e21e 1197 sv = *lelem++;
bdaf10a5
FC
1198 if (UNLIKELY(!sv)) {
1199 alias = TRUE;
1200 sv = *lelem++;
1201 ASSUME(SvTYPE(sv) == SVt_PVAV);
1202 }
a0d0e21e 1203 switch (SvTYPE(sv)) {
a5f48505
DM
1204 case SVt_PVAV: {
1205 bool already_copied = FALSE;
60edcf09 1206 ary = MUTABLE_AV(sv);
748a9306 1207 magic = SvMAGICAL(ary) != 0;
60edcf09
FC
1208 ENTER;
1209 SAVEFREESV(SvREFCNT_inc_simple_NN(sv));
a5f48505
DM
1210
1211 /* We need to clear ary. The is a danger that if we do this,
1212 * elements on the RHS may be prematurely freed, e.g.
1213 * @a = ($a[0]);
1214 * In the case of possible commonality, make a copy of each
1215 * RHS SV *before* clearing the array, and add a reference
1216 * from the tmps stack, so that it doesn't leak on death.
1217 * Otherwise, make a copy of each RHS SV only as we're storing
1218 * it into the array - that way we don't have to worry about
1219 * it being leaked if we die, but don't incur the cost of
1220 * mortalising everything.
1221 */
1222
1223 if ( (PL_op->op_private & OPpASSIGN_COMMON_AGG)
1224 && (relem <= lastrelem)
1225 && (magic || AvFILL(ary) != -1))
1226 {
1227 SV **svp;
1228 EXTEND_MORTAL(lastrelem - relem + 1);
1229 for (svp = relem; svp <= lastrelem; svp++) {
1230 *svp = sv_mortalcopy_flags(*svp,
1231 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
1232 TAINT_NOT;
1233 }
1234 already_copied = TRUE;
1235 }
1236
1237 av_clear(ary);
7e42bd57 1238 av_extend(ary, lastrelem - relem);
a0d0e21e
LW
1239 i = 0;
1240 while (relem <= lastrelem) { /* gobble up all the rest */
5117ca91 1241 SV **didstore;
bdaf10a5 1242 if (LIKELY(!alias)) {
a5f48505
DM
1243 if (already_copied)
1244 sv = *relem;
1245 else {
1246 if (LIKELY(*relem))
1247 /* before newSV, in case it dies */
1248 SvGETMAGIC(*relem);
1249 sv = newSV(0);
1250 sv_setsv_nomg(sv, *relem);
1251 *relem = sv;
1252 }
bdaf10a5
FC
1253 }
1254 else {
a5f48505
DM
1255 if (!already_copied)
1256 SvGETMAGIC(*relem);
bdaf10a5
FC
1257 if (!SvROK(*relem))
1258 DIE(aTHX_ "Assigned value is not a reference");
1259 if (SvTYPE(SvRV(*relem)) > SVt_PVLV)
1260 /* diag_listed_as: Assigned value is not %s reference */
1261 DIE(aTHX_
1262 "Assigned value is not a SCALAR reference");
a5f48505 1263 if (lval && !already_copied)
bdaf10a5
FC
1264 *relem = sv_mortalcopy(*relem);
1265 /* XXX else check for weak refs? */
1266 sv = SvREFCNT_inc_simple_NN(SvRV(*relem));
1267 }
1268 relem++;
a5f48505
DM
1269 if (already_copied)
1270 SvREFCNT_inc_simple_NN(sv); /* undo mortal free */
5117ca91
GS
1271 didstore = av_store(ary,i++,sv);
1272 if (magic) {
18024492
FC
1273 if (!didstore)
1274 sv_2mortal(sv);
8ef24240 1275 if (SvSMAGICAL(sv))
fb73857a 1276 mg_set(sv);
5117ca91 1277 }
bbce6d69 1278 TAINT_NOT;
a0d0e21e 1279 }
5d9574c1 1280 if (UNLIKELY(PL_delaymagic & DM_ARRAY_ISA))
ad64d0ec 1281 SvSETMAGIC(MUTABLE_SV(ary));
60edcf09 1282 LEAVE;
a0d0e21e 1283 break;
a5f48505
DM
1284 }
1285
10c8fecd 1286 case SVt_PVHV: { /* normal hash */
a0d0e21e 1287 SV *tmpstr;
1c4ea384
RZ
1288 int odd;
1289 int duplicates = 0;
45960564 1290 SV** topelem = relem;
1c4ea384 1291 SV **firsthashrelem = relem;
a5f48505 1292 bool already_copied = FALSE;
a0d0e21e 1293
60edcf09 1294 hash = MUTABLE_HV(sv);
748a9306 1295 magic = SvMAGICAL(hash) != 0;
1c4ea384
RZ
1296
1297 odd = ((lastrelem - firsthashrelem)&1)? 0 : 1;
5d9574c1 1298 if (UNLIKELY(odd)) {
fb8f4cf8 1299 do_oddball(lastrelem, firsthashrelem);
1d2b3927
HS
1300 /* we have firstlelem to reuse, it's not needed anymore
1301 */
1c4ea384
RZ
1302 *(lastrelem+1) = &PL_sv_undef;
1303 }
1304
60edcf09
FC
1305 ENTER;
1306 SAVEFREESV(SvREFCNT_inc_simple_NN(sv));
a5f48505
DM
1307
1308 /* We need to clear hash. The is a danger that if we do this,
1309 * elements on the RHS may be prematurely freed, e.g.
1310 * %h = (foo => $h{bar});
1311 * In the case of possible commonality, make a copy of each
1312 * RHS SV *before* clearing the hash, and add a reference
1313 * from the tmps stack, so that it doesn't leak on death.
1314 */
1315
1316 if ( (PL_op->op_private & OPpASSIGN_COMMON_AGG)
1317 && (relem <= lastrelem)
1318 && (magic || HvUSEDKEYS(hash)))
1319 {
1320 SV **svp;
1321 EXTEND_MORTAL(lastrelem - relem + 1);
1322 for (svp = relem; svp <= lastrelem; svp++) {
1323 *svp = sv_mortalcopy_flags(*svp,
1324 SV_GMAGIC|SV_DO_COW_SVSETSV|SV_NOSTEAL);
1325 TAINT_NOT;
1326 }
1327 already_copied = TRUE;
1328 }
1329
a0d0e21e 1330 hv_clear(hash);
a5f48505 1331
5d9574c1 1332 while (LIKELY(relem < lastrelem+odd)) { /* gobble up all the rest */
5117ca91 1333 HE *didstore;
1c4ea384 1334 assert(*relem);
632b9d6f
FC
1335 /* Copy the key if aassign is called in lvalue context,
1336 to avoid having the next op modify our rhs. Copy
1337 it also if it is gmagical, lest it make the
1338 hv_store_ent call below croak, leaking the value. */
a5f48505 1339 sv = (lval || SvGMAGICAL(*relem)) && !already_copied
632b9d6f
FC
1340 ? sv_mortalcopy(*relem)
1341 : *relem;
45960564 1342 relem++;
1c4ea384 1343 assert(*relem);
a5f48505
DM
1344 if (already_copied)
1345 tmpstr = *relem++;
1346 else {
1347 SvGETMAGIC(*relem);
1348 tmpstr = newSV(0);
1349 sv_setsv_nomg(tmpstr,*relem++); /* value */
1350 }
1351
a88bf2bc 1352 if (gimme == G_ARRAY) {
45960564
DM
1353 if (hv_exists_ent(hash, sv, 0))
1354 /* key overwrites an existing entry */
1355 duplicates += 2;
a88bf2bc 1356 else {
45960564 1357 /* copy element back: possibly to an earlier
1d2b3927
HS
1358 * stack location if we encountered dups earlier,
1359 * possibly to a later stack location if odd */
45960564
DM
1360 *topelem++ = sv;
1361 *topelem++ = tmpstr;
1362 }
1363 }
a5f48505
DM
1364 if (already_copied)
1365 SvREFCNT_inc_simple_NN(tmpstr); /* undo mortal free */
5117ca91 1366 didstore = hv_store_ent(hash,sv,tmpstr,0);
632b9d6f
FC
1367 if (magic) {
1368 if (!didstore) sv_2mortal(tmpstr);
1369 SvSETMAGIC(tmpstr);
1370 }
bbce6d69 1371 TAINT_NOT;
8e07c86e 1372 }
60edcf09 1373 LEAVE;
1c4ea384
RZ
1374 if (duplicates && gimme == G_ARRAY) {
1375 /* at this point we have removed the duplicate key/value
1376 * pairs from the stack, but the remaining values may be
1377 * wrong; i.e. with (a 1 a 2 b 3) on the stack we've removed
1378 * the (a 2), but the stack now probably contains
1379 * (a <freed> b 3), because { hv_save(a,1); hv_save(a,2) }
1380 * obliterates the earlier key. So refresh all values. */
1381 lastrelem -= duplicates;
1382 relem = firsthashrelem;
1383 while (relem < lastrelem+odd) {
1384 HE *he;
1385 he = hv_fetch_ent(hash, *relem++, 0, 0);
1386 *relem++ = (he ? HeVAL(he) : &PL_sv_undef);
1387 }
1388 }
1389 if (odd && gimme == G_ARRAY) lastrelem++;
a0d0e21e
LW
1390 }
1391 break;
1392 default:
6fc92669
GS
1393 if (SvIMMORTAL(sv)) {
1394 if (relem <= lastrelem)
1395 relem++;
1396 break;
a0d0e21e
LW
1397 }
1398 if (relem <= lastrelem) {
5d9574c1 1399 if (UNLIKELY(
1c70fb82
FC
1400 SvTEMP(sv) && !SvSMAGICAL(sv) && SvREFCNT(sv) == 1 &&
1401 (!isGV_with_GP(sv) || SvFAKE(sv)) && ckWARN(WARN_MISC)
5d9574c1 1402 ))
1c70fb82
FC
1403 Perl_warner(aTHX_
1404 packWARN(WARN_MISC),
1405 "Useless assignment to a temporary"
1406 );
a0d0e21e
LW
1407 sv_setsv(sv, *relem);
1408 *(relem++) = sv;
1409 }
1410 else
3280af22 1411 sv_setsv(sv, &PL_sv_undef);
8ef24240 1412 SvSETMAGIC(sv);
a0d0e21e
LW
1413 break;
1414 }
1415 }
5d9574c1 1416 if (UNLIKELY(PL_delaymagic & ~DM_DELAY)) {
985213f2 1417 /* Will be used to set PL_tainting below */
dfff4baf
BF
1418 Uid_t tmp_uid = PerlProc_getuid();
1419 Uid_t tmp_euid = PerlProc_geteuid();
1420 Gid_t tmp_gid = PerlProc_getgid();
1421 Gid_t tmp_egid = PerlProc_getegid();
985213f2 1422
b469f1e0 1423 /* XXX $> et al currently silently ignore failures */
3280af22 1424 if (PL_delaymagic & DM_UID) {
a0d0e21e 1425#ifdef HAS_SETRESUID
b469f1e0
JH
1426 PERL_UNUSED_RESULT(
1427 setresuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
1428 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1,
1429 (Uid_t)-1));
56febc5e
AD
1430#else
1431# ifdef HAS_SETREUID
b469f1e0
JH
1432 PERL_UNUSED_RESULT(
1433 setreuid((PL_delaymagic & DM_RUID) ? PL_delaymagic_uid : (Uid_t)-1,
1434 (PL_delaymagic & DM_EUID) ? PL_delaymagic_euid : (Uid_t)-1));
56febc5e
AD
1435# else
1436# ifdef HAS_SETRUID
b28d0864 1437 if ((PL_delaymagic & DM_UID) == DM_RUID) {
b469f1e0 1438 PERL_UNUSED_RESULT(setruid(PL_delaymagic_uid));
b28d0864 1439 PL_delaymagic &= ~DM_RUID;
a0d0e21e 1440 }
56febc5e
AD
1441# endif /* HAS_SETRUID */
1442# ifdef HAS_SETEUID
b28d0864 1443 if ((PL_delaymagic & DM_UID) == DM_EUID) {
b469f1e0 1444 PERL_UNUSED_RESULT(seteuid(PL_delaymagic_euid));
b28d0864 1445 PL_delaymagic &= ~DM_EUID;
a0d0e21e 1446 }
56febc5e 1447# endif /* HAS_SETEUID */
b28d0864 1448 if (PL_delaymagic & DM_UID) {
985213f2 1449 if (PL_delaymagic_uid != PL_delaymagic_euid)
cea2e8a9 1450 DIE(aTHX_ "No setreuid available");
b469f1e0 1451 PERL_UNUSED_RESULT(PerlProc_setuid(PL_delaymagic_uid));
a0d0e21e 1452 }
56febc5e
AD
1453# endif /* HAS_SETREUID */
1454#endif /* HAS_SETRESUID */
04783dc7 1455
985213f2
AB
1456 tmp_uid = PerlProc_getuid();
1457 tmp_euid = PerlProc_geteuid();
a0d0e21e 1458 }
b469f1e0 1459 /* XXX $> et al currently silently ignore failures */
3280af22 1460 if (PL_delaymagic & DM_GID) {
a0d0e21e 1461#ifdef HAS_SETRESGID
b469f1e0
JH
1462 PERL_UNUSED_RESULT(
1463 setresgid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
1464 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1,
1465 (Gid_t)-1));
56febc5e
AD
1466#else
1467# ifdef HAS_SETREGID
b469f1e0
JH
1468 PERL_UNUSED_RESULT(
1469 setregid((PL_delaymagic & DM_RGID) ? PL_delaymagic_gid : (Gid_t)-1,
1470 (PL_delaymagic & DM_EGID) ? PL_delaymagic_egid : (Gid_t)-1));
56febc5e
AD
1471# else
1472# ifdef HAS_SETRGID
b28d0864 1473 if ((PL_delaymagic & DM_GID) == DM_RGID) {
b469f1e0 1474 PERL_UNUSED_RESULT(setrgid(PL_delaymagic_gid));
b28d0864 1475 PL_delaymagic &= ~DM_RGID;
a0d0e21e 1476 }
56febc5e
AD
1477# endif /* HAS_SETRGID */
1478# ifdef HAS_SETEGID
b28d0864 1479 if ((PL_delaymagic & DM_GID) == DM_EGID) {
b469f1e0 1480 PERL_UNUSED_RESULT(setegid(PL_delaymagic_egid));
b28d0864 1481 PL_delaymagic &= ~DM_EGID;
a0d0e21e 1482 }
56febc5e 1483# endif /* HAS_SETEGID */
b28d0864 1484 if (PL_delaymagic & DM_GID) {
985213f2 1485 if (PL_delaymagic_gid != PL_delaymagic_egid)
cea2e8a9 1486 DIE(aTHX_ "No setregid available");
b469f1e0 1487 PERL_UNUSED_RESULT(PerlProc_setgid(PL_delaymagic_gid));
a0d0e21e 1488 }
56febc5e
AD
1489# endif /* HAS_SETREGID */
1490#endif /* HAS_SETRESGID */
04783dc7 1491
985213f2
AB
1492 tmp_gid = PerlProc_getgid();
1493 tmp_egid = PerlProc_getegid();
a0d0e21e 1494 }
284167a5 1495 TAINTING_set( TAINTING_get | (tmp_uid && (tmp_euid != tmp_uid || tmp_egid != tmp_gid)) );
9a9b5ec9
DM
1496#ifdef NO_TAINT_SUPPORT
1497 PERL_UNUSED_VAR(tmp_uid);
1498 PERL_UNUSED_VAR(tmp_euid);
1499 PERL_UNUSED_VAR(tmp_gid);
1500 PERL_UNUSED_VAR(tmp_egid);
1501#endif
a0d0e21e 1502 }
3280af22 1503 PL_delaymagic = 0;
54310121 1504
54310121
PP
1505 if (gimme == G_VOID)
1506 SP = firstrelem - 1;
1507 else if (gimme == G_SCALAR) {
1508 dTARGET;
1509 SP = firstrelem;
231cbeb2 1510 SETi(lastrelem - firstrelem + 1);
54310121
PP
1511 }
1512 else {
1c4ea384 1513 if (ary || hash)
1d2b3927
HS
1514 /* note that in this case *firstlelem may have been overwritten
1515 by sv_undef in the odd hash case */
a0d0e21e 1516 SP = lastrelem;
1c4ea384 1517 else {
a0d0e21e 1518 SP = firstrelem + (lastlelem - firstlelem);
1c4ea384
RZ
1519 lelem = firstlelem + (relem - firstrelem);
1520 while (relem <= SP)
1521 *relem++ = (lelem <= lastlelem) ? *lelem++ : &PL_sv_undef;
1522 }
a0d0e21e 1523 }
08aeb9f7 1524
54310121 1525 RETURN;
a0d0e21e
LW
1526}
1527
8782bef2
GB
1528PP(pp_qr)
1529{
20b7effb 1530 dSP;
eb578fdb 1531 PMOP * const pm = cPMOP;
fe578d7f 1532 REGEXP * rx = PM_GETRE(pm);
10599a69 1533 SV * const pkg = rx ? CALLREG_PACKAGE(rx) : NULL;
c4420975 1534 SV * const rv = sv_newmortal();
d63c20f2
DM
1535 CV **cvp;
1536 CV *cv;
288b8c02
NC
1537
1538 SvUPGRADE(rv, SVt_IV);
c2123ae3
NC
1539 /* For a subroutine describing itself as "This is a hacky workaround" I'm
1540 loathe to use it here, but it seems to be the right fix. Or close.
1541 The key part appears to be that it's essential for pp_qr to return a new
1542 object (SV), which implies that there needs to be an effective way to
1543 generate a new SV from the existing SV that is pre-compiled in the
1544 optree. */
1545 SvRV_set(rv, MUTABLE_SV(reg_temp_copy(NULL, rx)));
288b8c02
NC
1546 SvROK_on(rv);
1547
8d919b0a 1548 cvp = &( ReANY((REGEXP *)SvRV(rv))->qr_anoncv);
5d9574c1 1549 if (UNLIKELY((cv = *cvp) && CvCLONE(*cvp))) {
d63c20f2 1550 *cvp = cv_clone(cv);
fc2b2dca 1551 SvREFCNT_dec_NN(cv);
d63c20f2
DM
1552 }
1553
288b8c02 1554 if (pkg) {
f815daf2 1555 HV *const stash = gv_stashsv(pkg, GV_ADD);
fc2b2dca 1556 SvREFCNT_dec_NN(pkg);
288b8c02
NC
1557 (void)sv_bless(rv, stash);
1558 }
1559
5d9574c1 1560 if (UNLIKELY(RX_ISTAINTED(rx))) {
e08e52cf 1561 SvTAINTED_on(rv);
9274aefd
DM
1562 SvTAINTED_on(SvRV(rv));
1563 }
c8c13c22 1564 XPUSHs(rv);
1565 RETURN;
8782bef2
GB
1566}
1567
a0d0e21e
LW
1568PP(pp_match)
1569{
20b7effb 1570 dSP; dTARG;
eb578fdb 1571 PMOP *pm = cPMOP;
d65afb4b 1572 PMOP *dynpm = pm;
eb578fdb 1573 const char *s;
5c144d81 1574 const char *strend;
99a90e59 1575 SSize_t curpos = 0; /* initial pos() or current $+[0] */
a0d0e21e 1576 I32 global;
7fadf4a7 1577 U8 r_flags = 0;
5c144d81 1578 const char *truebase; /* Start of string */
eb578fdb 1579 REGEXP *rx = PM_GETRE(pm);
b3eb6a9b 1580 bool rxtainted;
82334630 1581 const I32 gimme = GIMME_V;
a0d0e21e 1582 STRLEN len;
a3b680e6 1583 const I32 oldsave = PL_savestack_ix;
e60df1fa 1584 I32 had_zerolen = 0;
b1422d62 1585 MAGIC *mg = NULL;
a0d0e21e 1586
533c011a 1587 if (PL_op->op_flags & OPf_STACKED)
a0d0e21e 1588 TARG = POPs;
6ffceeb7 1589 else if (ARGTARG)
59f00321 1590 GETTARGET;
a0d0e21e 1591 else {
54b9620d 1592 TARG = DEFSV;
a0d0e21e
LW
1593 EXTEND(SP,1);
1594 }
d9f424b2 1595
c277df42 1596 PUTBACK; /* EVAL blocks need stack_sp. */
69dc4b30
FC
1597 /* Skip get-magic if this is a qr// clone, because regcomp has
1598 already done it. */
f1d31338 1599 truebase = ReANY(rx)->mother_re
69dc4b30
FC
1600 ? SvPV_nomg_const(TARG, len)
1601 : SvPV_const(TARG, len);
f1d31338 1602 if (!truebase)
2269b42e 1603 DIE(aTHX_ "panic: pp_match");
f1d31338 1604 strend = truebase + len;
284167a5
SM
1605 rxtainted = (RX_ISTAINTED(rx) ||
1606 (TAINT_get && (pm->op_pmflags & PMf_RETAINT)));
9212bbba 1607 TAINT_NOT;
a0d0e21e 1608
6c864ec2 1609 /* We need to know this in case we fail out early - pos() must be reset */
de0df3c0
MH
1610 global = dynpm->op_pmflags & PMf_GLOBAL;
1611
d65afb4b 1612 /* PMdf_USED is set after a ?? matches once */
c737faaf
YO
1613 if (
1614#ifdef USE_ITHREADS
1615 SvREADONLY(PL_regex_pad[pm->op_pmoffset])
1616#else
1617 pm->op_pmflags & PMf_USED
1618#endif
1619 ) {
e5dc5375 1620 DEBUG_r(PerlIO_printf(Perl_debug_log, "?? already matched once"));
de0df3c0 1621 goto nope;
a0d0e21e
LW
1622 }
1623
7e313637
FC
1624 /* empty pattern special-cased to use last successful pattern if
1625 possible, except for qr// */
8d919b0a 1626 if (!ReANY(rx)->mother_re && !RX_PRELEN(rx)
7e313637 1627 && PL_curpm) {
3280af22 1628 pm = PL_curpm;
aaa362c4 1629 rx = PM_GETRE(pm);
a0d0e21e 1630 }
d65afb4b 1631
389ecb56 1632 if (RX_MINLEN(rx) >= 0 && (STRLEN)RX_MINLEN(rx) > len) {
75d43e96
FC
1633 DEBUG_r(PerlIO_printf(Perl_debug_log, "String shorter than min possible regex match (%"
1634 UVuf" < %"IVdf")\n",
1635 (UV)len, (IV)RX_MINLEN(rx)));
de0df3c0 1636 goto nope;
e5dc5375 1637 }
c277df42 1638
8ef97b0e 1639 /* get pos() if //g */
de0df3c0 1640 if (global) {
b1422d62 1641 mg = mg_find_mglob(TARG);
8ef97b0e 1642 if (mg && mg->mg_len >= 0) {
25fdce4a 1643 curpos = MgBYTEPOS(mg, TARG, truebase, len);
8ef97b0e
DM
1644 /* last time pos() was set, it was zero-length match */
1645 if (mg->mg_flags & MGf_MINMATCH)
1646 had_zerolen = 1;
1647 }
a0d0e21e 1648 }
8ef97b0e 1649
6e240d0b 1650#ifdef PERL_SAWAMPERSAND
a41aa44d 1651 if ( RX_NPARENS(rx)
6502e081 1652 || PL_sawampersand
6502e081 1653 || (RX_EXTFLAGS(rx) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
5b0e71e9 1654 || (dynpm->op_pmflags & PMf_KEEPCOPY)
6e240d0b
FC
1655 )
1656#endif
1657 {
6502e081
DM
1658 r_flags |= (REXEC_COPY_STR|REXEC_COPY_SKIP_PRE);
1659 /* in @a =~ /(.)/g, we iterate multiple times, but copy the buffer
1660 * only on the first iteration. Therefore we need to copy $' as well
1661 * as $&, to make the rest of the string available for captures in
1662 * subsequent iterations */
1663 if (! (global && gimme == G_ARRAY))
1664 r_flags |= REXEC_COPY_SKIP_POST;
1665 };
5b0e71e9
DM
1666#ifdef PERL_SAWAMPERSAND
1667 if (dynpm->op_pmflags & PMf_KEEPCOPY)
1668 /* handle KEEPCOPY in pmop but not rx, eg $r=qr/a/; /$r/p */
1669 r_flags &= ~(REXEC_COPY_SKIP_PRE|REXEC_COPY_SKIP_POST);
1670#endif
22e551b9 1671
f1d31338
DM
1672 s = truebase;
1673
d7be1480 1674 play_it_again:
985afbc1 1675 if (global)
03c83e26 1676 s = truebase + curpos;
f722798b 1677
77da2310 1678 if (!CALLREGEXEC(rx, (char*)s, (char *)strend, (char*)truebase,
03c83e26 1679 had_zerolen, TARG, NULL, r_flags))
03b6c93d 1680 goto nope;
77da2310
NC
1681
1682 PL_curpm = pm;
985afbc1 1683 if (dynpm->op_pmflags & PMf_ONCE)
c737faaf 1684#ifdef USE_ITHREADS
77da2310 1685 SvREADONLY_on(PL_regex_pad[dynpm->op_pmoffset]);
c737faaf 1686#else
77da2310 1687 dynpm->op_pmflags |= PMf_USED;
c737faaf 1688#endif
a0d0e21e 1689
72311751
GS
1690 if (rxtainted)
1691 RX_MATCH_TAINTED_on(rx);
1692 TAINT_IF(RX_MATCH_TAINTED(rx));
35c2ccc3
DM
1693
1694 /* update pos */
1695
1696 if (global && (gimme != G_ARRAY || (dynpm->op_pmflags & PMf_CONTINUE))) {
b1422d62 1697 if (!mg)
35c2ccc3 1698 mg = sv_magicext_mglob(TARG);
25fdce4a 1699 MgBYTEPOS_set(mg, TARG, truebase, RX_OFFS(rx)[0].end);
adf51885
DM
1700 if (RX_ZERO_LEN(rx))
1701 mg->mg_flags |= MGf_MINMATCH;
1702 else
1703 mg->mg_flags &= ~MGf_MINMATCH;
35c2ccc3
DM
1704 }
1705
bf9dff51
DM
1706 if ((!RX_NPARENS(rx) && !global) || gimme != G_ARRAY) {
1707 LEAVE_SCOPE(oldsave);
1708 RETPUSHYES;
1709 }
1710
88ab22af
DM
1711 /* push captures on stack */
1712
bf9dff51 1713 {
07bc277f 1714 const I32 nparens = RX_NPARENS(rx);
a3b680e6 1715 I32 i = (global && !nparens) ? 1 : 0;
a0d0e21e 1716
c277df42 1717 SPAGAIN; /* EVAL blocks could move the stack. */
ffc61ed2
JH
1718 EXTEND(SP, nparens + i);
1719 EXTEND_MORTAL(nparens + i);
1720 for (i = !i; i <= nparens; i++) {
a0d0e21e 1721 PUSHs(sv_newmortal());
5d9574c1
DM
1722 if (LIKELY((RX_OFFS(rx)[i].start != -1)
1723 && RX_OFFS(rx)[i].end != -1 ))
1724 {
07bc277f 1725 const I32 len = RX_OFFS(rx)[i].end - RX_OFFS(rx)[i].start;
f1d31338 1726 const char * const s = RX_OFFS(rx)[i].start + truebase;
5d9574c1
DM
1727 if (UNLIKELY(RX_OFFS(rx)[i].end < 0 || RX_OFFS(rx)[i].start < 0
1728 || len < 0 || len > strend - s))
5637ef5b
NC
1729 DIE(aTHX_ "panic: pp_match start/end pointers, i=%ld, "
1730 "start=%ld, end=%ld, s=%p, strend=%p, len=%"UVuf,
1731 (long) i, (long) RX_OFFS(rx)[i].start,
1732 (long)RX_OFFS(rx)[i].end, s, strend, (UV) len);
a0d0e21e 1733 sv_setpvn(*SP, s, len);
cce850e4 1734 if (DO_UTF8(TARG) && is_utf8_string((U8*)s, len))
a197cbdd 1735 SvUTF8_on(*SP);
a0d0e21e
LW
1736 }
1737 }
1738 if (global) {
0e0b3e82 1739 curpos = (UV)RX_OFFS(rx)[0].end;
03c83e26 1740 had_zerolen = RX_ZERO_LEN(rx);
c277df42 1741 PUTBACK; /* EVAL blocks may use stack */
cf93c79d 1742 r_flags |= REXEC_IGNOREPOS | REXEC_NOT_FIRST;
a0d0e21e
LW
1743 goto play_it_again;
1744 }
4633a7c4 1745 LEAVE_SCOPE(oldsave);
a0d0e21e
LW
1746 RETURN;
1747 }
e5964223 1748 NOT_REACHED; /* NOTREACHED */
a0d0e21e 1749
7b52d656 1750 nope:
d65afb4b 1751 if (global && !(dynpm->op_pmflags & PMf_CONTINUE)) {
b1422d62
DM
1752 if (!mg)
1753 mg = mg_find_mglob(TARG);
1754 if (mg)
1755 mg->mg_len = -1;
a0d0e21e 1756 }
4633a7c4 1757 LEAVE_SCOPE(oldsave);
a0d0e21e
LW
1758 if (gimme == G_ARRAY)
1759 RETURN;
1760 RETPUSHNO;
1761}
1762
1763OP *
864dbfa3 1764Perl_do_readline(pTHX)
a0d0e21e 1765{
20b7effb 1766 dSP; dTARGETSTACKED;
eb578fdb 1767 SV *sv;
a0d0e21e
LW
1768 STRLEN tmplen = 0;
1769 STRLEN offset;
760ac839 1770 PerlIO *fp;
eb578fdb
KW
1771 IO * const io = GvIO(PL_last_in_gv);
1772 const I32 type = PL_op->op_type;
a3b680e6 1773 const I32 gimme = GIMME_V;
a0d0e21e 1774
6136c704 1775 if (io) {
50db69d8 1776 const MAGIC *const mg = SvTIED_mg((const SV *)io, PERL_MAGIC_tiedscalar);
6136c704 1777 if (mg) {
3e0cb5de 1778 Perl_tied_method(aTHX_ SV_CONST(READLINE), SP, MUTABLE_SV(io), mg, gimme, 0);
6136c704 1779 if (gimme == G_SCALAR) {
50db69d8
NC
1780 SPAGAIN;
1781 SvSetSV_nosteal(TARG, TOPs);
1782 SETTARG;
6136c704 1783 }
50db69d8 1784 return NORMAL;
0b7c7b4f 1785 }
e79b0511 1786 }
4608196e 1787 fp = NULL;
a0d0e21e
LW
1788 if (io) {
1789 fp = IoIFP(io);
1790 if (!fp) {
1791 if (IoFLAGS(io) & IOf_ARGV) {
1792 if (IoFLAGS(io) & IOf_START) {
a0d0e21e 1793 IoLINES(io) = 0;
b9f2b683 1794 if (av_tindex(GvAVn(PL_last_in_gv)) < 0) {
1d7c1841 1795 IoFLAGS(io) &= ~IOf_START;
d5eb9a46 1796 do_open6(PL_last_in_gv, "-", 1, NULL, NULL, 0);
4bac9ae4 1797 SvTAINTED_off(GvSVn(PL_last_in_gv)); /* previous tainting irrelevant */
76f68e9b 1798 sv_setpvs(GvSVn(PL_last_in_gv), "-");
3280af22 1799 SvSETMAGIC(GvSV(PL_last_in_gv));
a2008d6d
GS
1800 fp = IoIFP(io);
1801 goto have_fp;
a0d0e21e
LW
1802 }
1803 }
157fb5a1 1804 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
a0d0e21e 1805 if (!fp) { /* Note: fp != IoIFP(io) */
3280af22 1806 (void)do_close(PL_last_in_gv, FALSE); /* now it does*/
a0d0e21e
LW
1807 }
1808 }
0d44d22b
NC
1809 else if (type == OP_GLOB)
1810 fp = Perl_start_glob(aTHX_ POPs, io);
a0d0e21e
LW
1811 }
1812 else if (type == OP_GLOB)
1813 SP--;
7716c5c5 1814 else if (IoTYPE(io) == IoTYPE_WRONLY) {
a5390457 1815 report_wrongway_fh(PL_last_in_gv, '>');
a00b5bd3 1816 }
a0d0e21e
LW
1817 }
1818 if (!fp) {
041457d9 1819 if ((!io || !(IoFLAGS(io) & IOf_START))
de7dabb6
TC
1820 && ckWARN(WARN_CLOSED)
1821 && type != OP_GLOB)
041457d9 1822 {
de7dabb6 1823 report_evil_fh(PL_last_in_gv);
3f4520fe 1824 }
54310121 1825 if (gimme == G_SCALAR) {
79628082 1826 /* undef TARG, and push that undefined value */
ba92458f 1827 if (type != OP_RCATLINE) {
aab1202a 1828 sv_setsv(TARG,NULL);
ba92458f 1829 }
a0d0e21e
LW
1830 PUSHTARG;
1831 }
1832 RETURN;
1833 }
a2008d6d 1834 have_fp:
54310121 1835 if (gimme == G_SCALAR) {
a0d0e21e 1836 sv = TARG;
0f722b55
RGS
1837 if (type == OP_RCATLINE && SvGMAGICAL(sv))
1838 mg_get(sv);
48de12d9
RGS
1839 if (SvROK(sv)) {
1840 if (type == OP_RCATLINE)
5668452f 1841 SvPV_force_nomg_nolen(sv);
48de12d9
RGS
1842 else
1843 sv_unref(sv);
1844 }
f7877b28 1845 else if (isGV_with_GP(sv)) {
5668452f 1846 SvPV_force_nomg_nolen(sv);
f7877b28 1847 }
862a34c6 1848 SvUPGRADE(sv, SVt_PV);
a0d0e21e 1849 tmplen = SvLEN(sv); /* remember if already alloced */
e3918bb7 1850 if (!tmplen && !SvREADONLY(sv) && !SvIsCOW(sv)) {
f72e8700
JJ
1851 /* try short-buffering it. Please update t/op/readline.t
1852 * if you change the growth length.
1853 */
1854 Sv_Grow(sv, 80);
1855 }
2b5e58c4
AMS
1856 offset = 0;
1857 if (type == OP_RCATLINE && SvOK(sv)) {
1858 if (!SvPOK(sv)) {
5668452f 1859 SvPV_force_nomg_nolen(sv);
2b5e58c4 1860 }
a0d0e21e 1861 offset = SvCUR(sv);
2b5e58c4 1862 }
a0d0e21e 1863 }
54310121 1864 else {
561b68a9 1865 sv = sv_2mortal(newSV(80));
54310121
PP
1866 offset = 0;
1867 }
fbad3eb5 1868
3887d568
AP
1869 /* This should not be marked tainted if the fp is marked clean */
1870#define MAYBE_TAINT_LINE(io, sv) \
1871 if (!(IoFLAGS(io) & IOf_UNTAINT)) { \
1872 TAINT; \
1873 SvTAINTED_on(sv); \
1874 }
1875
684bef36 1876/* delay EOF state for a snarfed empty file */
fbad3eb5 1877#define SNARF_EOF(gimme,rs,io,sv) \
684bef36 1878 (gimme != G_SCALAR || SvCUR(sv) \
b9fee9ba 1879 || (IoFLAGS(io) & IOf_NOLINE) || !RsSNARF(rs))
fbad3eb5 1880
a0d0e21e 1881 for (;;) {
09e8efcc 1882 PUTBACK;
fbad3eb5 1883 if (!sv_gets(sv, fp, offset)
2d726892
TF
1884 && (type == OP_GLOB
1885 || SNARF_EOF(gimme, PL_rs, io, sv)
1886 || PerlIO_error(fp)))
fbad3eb5 1887 {
760ac839 1888 PerlIO_clearerr(fp);
a0d0e21e 1889 if (IoFLAGS(io) & IOf_ARGV) {
157fb5a1 1890 fp = nextargv(PL_last_in_gv, PL_op->op_flags & OPf_SPECIAL);
a0d0e21e
LW
1891 if (fp)
1892 continue;
3280af22 1893 (void)do_close(PL_last_in_gv, FALSE);
a0d0e21e
LW
1894 }
1895 else if (type == OP_GLOB) {
a2a5de95
NC
1896 if (!do_close(PL_last_in_gv, FALSE)) {
1897 Perl_ck_warner(aTHX_ packWARN(WARN_GLOB),
1898 "glob failed (child exited with status %d%s)",
1899 (int)(STATUS_CURRENT >> 8),
1900 (STATUS_CURRENT & 0x80) ? ", core dumped" : "");
4eb79ab5 1901 }
a0d0e21e 1902 }
54310121 1903 if (gimme == G_SCALAR) {
ba92458f
AE
1904 if (type != OP_RCATLINE) {
1905 SV_CHECK_THINKFIRST_COW_DROP(TARG);
0c34ef67 1906 SvOK_off(TARG);
ba92458f 1907 }
09e8efcc 1908 SPAGAIN;
a0d0e21e
LW
1909 PUSHTARG;
1910 }
3887d568 1911 MAYBE_TAINT_LINE(io, sv);
a0d0e21e
LW
1912 RETURN;
1913 }
3887d568 1914 MAYBE_TAINT_LINE(io, sv);
a0d0e21e 1915 IoLINES(io)++;
b9fee9ba 1916 IoFLAGS(io) |= IOf_NOLINE;
71be2cbc 1917 SvSETMAGIC(sv);
09e8efcc 1918 SPAGAIN;
a0d0e21e 1919 XPUSHs(sv);
a0d0e21e 1920 if (type == OP_GLOB) {
349d4f2f 1921 const char *t1;
a0d0e21e 1922
3280af22 1923 if (SvCUR(sv) > 0 && SvCUR(PL_rs) > 0) {
6136c704 1924 char * const tmps = SvEND(sv) - 1;
aa07b2f6 1925 if (*tmps == *SvPVX_const(PL_rs)) {
c07a80fd 1926 *tmps = '\0';
b162af07 1927 SvCUR_set(sv, SvCUR(sv) - 1);
c07a80fd
PP
1928 }
1929 }
349d4f2f 1930 for (t1 = SvPVX_const(sv); *t1; t1++)
b51c3e77
CB
1931#ifdef __VMS
1932 if (strchr("*%?", *t1))
1933#else
7ad1e72d 1934 if (strchr("$&*(){}[]'\";\\|?<>~`", *t1))
b51c3e77 1935#endif
a0d0e21e 1936 break;
349d4f2f 1937 if (*t1 && PerlLIO_lstat(SvPVX_const(sv), &PL_statbuf) < 0) {
a0d0e21e
LW
1938 (void)POPs; /* Unmatched wildcard? Chuck it... */
1939 continue;
1940 }
2d79bf7f 1941 } else if (SvUTF8(sv)) { /* OP_READLINE, OP_RCATLINE */
d4c19fe8
AL
1942 if (ckWARN(WARN_UTF8)) {
1943 const U8 * const s = (const U8*)SvPVX_const(sv) + offset;
1944 const STRLEN len = SvCUR(sv) - offset;
1945 const U8 *f;
1946
1947 if (!is_utf8_string_loc(s, len, &f))
1948 /* Emulate :encoding(utf8) warning in the same case. */
1949 Perl_warner(aTHX_ packWARN(WARN_UTF8),
1950 "utf8 \"\\x%02X\" does not map to Unicode",
1951 f < (U8*)SvEND(sv) ? *f : 0);
1952 }
a0d0e21e 1953 }
54310121 1954 if (gimme == G_ARRAY) {
a0d0e21e 1955 if (SvLEN(sv) - SvCUR(sv) > 20) {
1da4ca5f 1956 SvPV_shrink_to_cur(sv);
a0d0e21e 1957 }
561b68a9 1958 sv = sv_2mortal(newSV(80));
a0d0e21e
LW
1959 continue;
1960 }
54310121 1961 else if (gimme == G_SCALAR && !tmplen && SvLEN(sv) - SvCUR(sv) > 80) {
a0d0e21e 1962 /* try to reclaim a bit of scalar space (only on 1st alloc) */
d5b5861b
NC
1963 const STRLEN new_len
1964 = SvCUR(sv) < 60 ? 80 : SvCUR(sv)+40; /* allow some slop */
1da4ca5f 1965 SvPV_renew(sv, new_len);
a0d0e21e
LW
1966 }
1967 RETURN;
1968 }
1969}
1970
a0d0e21e
LW
1971PP(pp_helem)
1972{
20b7effb 1973 dSP;
760ac839 1974 HE* he;
ae77835f 1975 SV **svp;
c445ea15 1976 SV * const keysv = POPs;
85fbaab2 1977 HV * const hv = MUTABLE_HV(POPs);
a3b680e6
AL
1978 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
1979 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
be6c24e0 1980 SV *sv;
92970b93 1981 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
d30e492c 1982 bool preeminent = TRUE;
a0d0e21e 1983
6dfc73ea
SM
1984 if (SvTYPE(hv) != SVt_PVHV)
1985 RETPUSHUNDEF;
d4c19fe8 1986
92970b93 1987 if (localizing) {
d4c19fe8
AL
1988 MAGIC *mg;
1989 HV *stash;
d30e492c
VP
1990
1991 /* If we can determine whether the element exist,
1992 * Try to preserve the existenceness of a tied hash
1993 * element by using EXISTS and DELETE if possible.
1994 * Fallback to FETCH and STORE otherwise. */
2c5f48c2 1995 if (SvCANEXISTDELETE(hv))
d30e492c 1996 preeminent = hv_exists_ent(hv, keysv, 0);
d4c19fe8 1997 }
d30e492c 1998
5f9d7e2b 1999 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
d4c19fe8 2000 svp = he ? &HeVAL(he) : NULL;
a0d0e21e 2001 if (lval) {
746f6409 2002 if (!svp || !*svp || *svp == &PL_sv_undef) {
68dc0745
PP
2003 SV* lv;
2004 SV* key2;
2d8e6c8d 2005 if (!defer) {
be2597df 2006 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2d8e6c8d 2007 }
68dc0745
PP
2008 lv = sv_newmortal();
2009 sv_upgrade(lv, SVt_PVLV);
2010 LvTYPE(lv) = 'y';
6136c704 2011 sv_magic(lv, key2 = newSVsv(keysv), PERL_MAGIC_defelem, NULL, 0);
fc2b2dca 2012 SvREFCNT_dec_NN(key2); /* sv_magic() increments refcount */
b37c2d43 2013 LvTARG(lv) = SvREFCNT_inc_simple(hv);
68dc0745
PP
2014 LvTARGLEN(lv) = 1;
2015 PUSHs(lv);
2016 RETURN;
2017 }
92970b93 2018 if (localizing) {
bfcb3514 2019 if (HvNAME_get(hv) && isGV(*svp))
159b6efe 2020 save_gp(MUTABLE_GV(*svp), !(PL_op->op_flags & OPf_SPECIAL));
47cfc530
VP
2021 else if (preeminent)
2022 save_helem_flags(hv, keysv, svp,
2023 (PL_op->op_flags & OPf_SPECIAL) ? 0 : SAVEf_SETMAGIC);
2024 else
2025 SAVEHDELETE(hv, keysv);
5f05dabc 2026 }
9026059d
GG
2027 else if (PL_op->op_private & OPpDEREF) {
2028 PUSHs(vivify_ref(*svp, PL_op->op_private & OPpDEREF));
2029 RETURN;
2030 }
a0d0e21e 2031 }
746f6409 2032 sv = (svp && *svp ? *svp : &PL_sv_undef);
fd69380d
DM
2033 /* Originally this did a conditional C<sv = sv_mortalcopy(sv)>; this
2034 * was to make C<local $tied{foo} = $tied{foo}> possible.
2035 * However, it seems no longer to be needed for that purpose, and
2036 * introduced a new bug: stuff like C<while ($hash{taintedval} =~ /.../g>
2037 * would loop endlessly since the pos magic is getting set on the
2038 * mortal copy and lost. However, the copy has the effect of
2039 * triggering the get magic, and losing it altogether made things like
2040 * c<$tied{foo};> in void context no longer do get magic, which some
2041 * code relied on. Also, delayed triggering of magic on @+ and friends
2042 * meant the original regex may be out of scope by now. So as a
2043 * compromise, do the get magic here. (The MGf_GSKIP flag will stop it
2044 * being called too many times). */
39cf747a 2045 if (!lval && SvRMAGICAL(hv) && SvGMAGICAL(sv))
fd69380d 2046 mg_get(sv);
be6c24e0 2047 PUSHs(sv);
a0d0e21e
LW
2048 RETURN;
2049}
2050
fedf30e1
DM
2051
2052/* a stripped-down version of Perl_softref2xv() for use by
2053 * pp_multideref(), which doesn't use PL_op->op_flags */
2054
2055GV *
2056S_softref2xv_lite(pTHX_ SV *const sv, const char *const what,
2057 const svtype type)
2058{
2059 if (PL_op->op_private & HINT_STRICT_REFS) {
2060 if (SvOK(sv))
2061 Perl_die(aTHX_ PL_no_symref_sv, sv,
2062 (SvPOKp(sv) && SvCUR(sv)>32 ? "..." : ""), what);
2063 else
2064 Perl_die(aTHX_ PL_no_usym, what);
2065 }
2066 if (!SvOK(sv))
2067 Perl_die(aTHX_ PL_no_usym, what);
2068 return gv_fetchsv_nomg(sv, GV_ADD, type);
2069}
2070
2071
79815f56
DM
2072/* Handle one or more aggregate derefs and array/hash indexings, e.g.
2073 * $h->{foo} or $a[0]{$key}[$i] or f()->[1]
fedf30e1
DM
2074 *
2075 * op_aux points to an array of unions of UV / IV / SV* / PADOFFSET.
79815f56
DM
2076 * Each of these either contains a set of actions, or an argument, such as
2077 * an IV to use as an array index, or a lexical var to retrieve.
2078 * Several actions re stored per UV; we keep shifting new actions off the
2079 * one UV, and only reload when it becomes zero.
fedf30e1
DM
2080 */
2081
2082PP(pp_multideref)
2083{
2084 SV *sv = NULL; /* init to avoid spurious 'may be used uninitialized' */
2085 UNOP_AUX_item *items = cUNOP_AUXx(PL_op)->op_aux;
2086 UV actions = items->uv;
2087
2088 assert(actions);
2089 /* this tells find_uninit_var() where we're up to */
2090 PL_multideref_pc = items;
2091
2092 while (1) {
2093 /* there are three main classes of action; the first retrieve
2094 * the initial AV or HV from a variable or the stack; the second
2095 * does the equivalent of an unrolled (/DREFAV, rv2av, aelem),
2096 * the third an unrolled (/DREFHV, rv2hv, helem).
2097 */
2098 switch (actions & MDEREF_ACTION_MASK) {
2099
2100 case MDEREF_reload:
2101 actions = (++items)->uv;
2102 continue;
2103
2104 case MDEREF_AV_padav_aelem: /* $lex[...] */
2105 sv = PAD_SVl((++items)->pad_offset);
2106 goto do_AV_aelem;
2107
2108 case MDEREF_AV_gvav_aelem: /* $pkg[...] */
2109 sv = UNOP_AUX_item_sv(++items);
2110 assert(isGV_with_GP(sv));
2111 sv = (SV*)GvAVn((GV*)sv);
2112 goto do_AV_aelem;
2113
2114 case MDEREF_AV_pop_rv2av_aelem: /* expr->[...] */
2115 {
2116 dSP;
2117 sv = POPs;
2118 PUTBACK;
2119 goto do_AV_rv2av_aelem;
2120 }
2121
2122 case MDEREF_AV_gvsv_vivify_rv2av_aelem: /* $pkg->[...] */
2123 sv = UNOP_AUX_item_sv(++items);
2124 assert(isGV_with_GP(sv));
2125 sv = GvSVn((GV*)sv);
2126 goto do_AV_vivify_rv2av_aelem;
2127
2128 case MDEREF_AV_padsv_vivify_rv2av_aelem: /* $lex->[...] */
2129 sv = PAD_SVl((++items)->pad_offset);
2130 /* FALLTHROUGH */
2131
2132 do_AV_vivify_rv2av_aelem:
2133 case MDEREF_AV_vivify_rv2av_aelem: /* vivify, ->[...] */
2134 /* this is the OPpDEREF action normally found at the end of
2135 * ops like aelem, helem, rv2sv */
2136 sv = vivify_ref(sv, OPpDEREF_AV);
2137 /* FALLTHROUGH */
2138
2139 do_AV_rv2av_aelem:
2140 /* this is basically a copy of pp_rv2av when it just has the
2141 * sKR/1 flags */
2142 SvGETMAGIC(sv);
2143 if (LIKELY(SvROK(sv))) {
2144 if (UNLIKELY(SvAMAGIC(sv))) {
2145 sv = amagic_deref_call(sv, to_av_amg);
2146 }
2147 sv = SvRV(sv);
2148 if (UNLIKELY(SvTYPE(sv) != SVt_PVAV))
2149 DIE(aTHX_ "Not an ARRAY reference");
2150 }
2151 else if (SvTYPE(sv) != SVt_PVAV) {
2152 if (!isGV_with_GP(sv))
2153 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "an ARRAY", SVt_PVAV);
2154 sv = MUTABLE_SV(GvAVn((GV*)sv));
2155 }
2156 /* FALLTHROUGH */
2157
2158 do_AV_aelem:
2159 {
2160 /* retrieve the key; this may be either a lexical or package
2161 * var (whose index/ptr is stored as an item) or a signed
2162 * integer constant stored as an item.
2163 */
2164 SV *elemsv;
2165 IV elem = 0; /* to shut up stupid compiler warnings */
2166
2167
2168 assert(SvTYPE(sv) == SVt_PVAV);
2169
2170 switch (actions & MDEREF_INDEX_MASK) {
2171 case MDEREF_INDEX_none:
2172 goto finish;
2173 case MDEREF_INDEX_const:
2174 elem = (++items)->iv;
2175 break;
2176 case MDEREF_INDEX_padsv:
2177 elemsv = PAD_SVl((++items)->pad_offset);
2178 goto check_elem;
2179 case MDEREF_INDEX_gvsv:
2180 elemsv = UNOP_AUX_item_sv(++items);
2181 assert(isGV_with_GP(elemsv));
2182 elemsv = GvSVn((GV*)elemsv);
2183 check_elem:
2184 if (UNLIKELY(SvROK(elemsv) && !SvGAMAGIC(elemsv)
2185 && ckWARN(WARN_MISC)))
2186 Perl_warner(aTHX_ packWARN(WARN_MISC),
2187 "Use of reference \"%"SVf"\" as array index",
2188 SVfARG(elemsv));
2189 /* the only time that S_find_uninit_var() needs this
2190 * is to determine which index value triggered the
2191 * undef warning. So just update it here. Note that
2192 * since we don't save and restore this var (e.g. for
2193 * tie or overload execution), its value will be
2194 * meaningless apart from just here */
2195 PL_multideref_pc = items;
2196 elem = SvIV(elemsv);
2197 break;
2198 }
2199
2200
2201 /* this is basically a copy of pp_aelem with OPpDEREF skipped */
2202
2203 if (!(actions & MDEREF_FLAG_last)) {
2204 SV** svp = av_fetch((AV*)sv, elem, 1);
2205 if (!svp || ! (sv=*svp))
2206 DIE(aTHX_ PL_no_aelem, elem);
2207 break;
2208 }
2209
2210 if (PL_op->op_private &
2211 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
2212 {
2213 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
2214 sv = av_exists((AV*)sv, elem) ? &PL_sv_yes : &PL_sv_no;
2215 }
2216 else {
2217 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
2218 sv = av_delete((AV*)sv, elem, discard);
2219 if (discard)
2220 return NORMAL;
2221 if (!sv)
2222 sv = &PL_sv_undef;
2223 }
2224 }
2225 else {
2226 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2227 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
2228 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
2229 bool preeminent = TRUE;
2230 AV *const av = (AV*)sv;
2231 SV** svp;
2232
2233 if (UNLIKELY(localizing)) {
2234 MAGIC *mg;
2235 HV *stash;
2236
2237 /* If we can determine whether the element exist,
2238 * Try to preserve the existenceness of a tied array
2239 * element by using EXISTS and DELETE if possible.
2240 * Fallback to FETCH and STORE otherwise. */
2241 if (SvCANEXISTDELETE(av))
2242 preeminent = av_exists(av, elem);
2243 }
2244
2245 svp = av_fetch(av, elem, lval && !defer);
2246
2247 if (lval) {
2248 if (!svp || !(sv = *svp)) {
2249 IV len;
2250 if (!defer)
2251 DIE(aTHX_ PL_no_aelem, elem);
2252 len = av_tindex(av);
2253 sv = sv_2mortal(newSVavdefelem(av,
2254 /* Resolve a negative index now, unless it points
2255 * before the beginning of the array, in which
2256 * case record it for error reporting in
2257 * magic_setdefelem. */
2258 elem < 0 && len + elem >= 0
2259 ? len + elem : elem, 1));
2260 }
2261 else {
2262 if (UNLIKELY(localizing)) {
2263 if (preeminent) {
2264 save_aelem(av, elem, svp);
2265 sv = *svp; /* may have changed */
2266 }
2267 else
2268 SAVEADELETE(av, elem);
2269 }
2270 }
2271 }
2272 else {
2273 sv = (svp ? *svp : &PL_sv_undef);
2274 /* see note in pp_helem() */
2275 if (SvRMAGICAL(av) && SvGMAGICAL(sv))
2276 mg_get(sv);
2277 }
2278 }
2279
2280 }
2281 finish:
2282 {
2283 dSP;
2284 XPUSHs(sv);
2285 RETURN;
2286 }
2287 /* NOTREACHED */
2288
2289
2290
2291
2292 case MDEREF_HV_padhv_helem: /* $lex{...} */
2293 sv = PAD_SVl((++items)->pad_offset);
2294 goto do_HV_helem;
2295
2296 case MDEREF_HV_gvhv_helem: /* $pkg{...} */
2297 sv = UNOP_AUX_item_sv(++items);
2298 assert(isGV_with_GP(sv));
2299 sv = (SV*)GvHVn((GV*)sv);
2300 goto do_HV_helem;
2301
2302 case MDEREF_HV_pop_rv2hv_helem: /* expr->{...} */
2303 {
2304 dSP;
2305 sv = POPs;
2306 PUTBACK;
2307 goto do_HV_rv2hv_helem;
2308 }
2309
2310 case MDEREF_HV_gvsv_vivify_rv2hv_helem: /* $pkg->{...} */
2311 sv = UNOP_AUX_item_sv(++items);
2312 assert(isGV_with_GP(sv));
2313 sv = GvSVn((GV*)sv);
2314 goto do_HV_vivify_rv2hv_helem;
2315
2316 case MDEREF_HV_padsv_vivify_rv2hv_helem: /* $lex->{...} */
2317 sv = PAD_SVl((++items)->pad_offset);
2318 /* FALLTHROUGH */
2319
2320 do_HV_vivify_rv2hv_helem:
2321 case MDEREF_HV_vivify_rv2hv_helem: /* vivify, ->{...} */
2322 /* this is the OPpDEREF action normally found at the end of
2323 * ops like aelem, helem, rv2sv */
2324 sv = vivify_ref(sv, OPpDEREF_HV);
2325 /* FALLTHROUGH */
2326
2327 do_HV_rv2hv_helem:
2328 /* this is basically a copy of pp_rv2hv when it just has the
2329 * sKR/1 flags (and pp_rv2hv is aliased to pp_rv2av) */
2330
2331 SvGETMAGIC(sv);
2332 if (LIKELY(SvROK(sv))) {
2333 if (UNLIKELY(SvAMAGIC(sv))) {
2334 sv = amagic_deref_call(sv, to_hv_amg);
2335 }
2336 sv = SvRV(sv);
2337 if (UNLIKELY(SvTYPE(sv) != SVt_PVHV))
2338 DIE(aTHX_ "Not a HASH reference");
2339 }
2340 else if (SvTYPE(sv) != SVt_PVHV) {
2341 if (!isGV_with_GP(sv))
2342 sv = (SV*)S_softref2xv_lite(aTHX_ sv, "a HASH", SVt_PVHV);
2343 sv = MUTABLE_SV(GvHVn((GV*)sv));
2344 }
2345 /* FALLTHROUGH */
2346
2347 do_HV_helem:
2348 {
2349 /* retrieve the key; this may be either a lexical / package
2350 * var or a string constant, whose index/ptr is stored as an
2351 * item
2352 */
2353 SV *keysv = NULL; /* to shut up stupid compiler warnings */
2354
2355 assert(SvTYPE(sv) == SVt_PVHV);
2356
2357 switch (actions & MDEREF_INDEX_MASK) {
2358 case MDEREF_INDEX_none:
2359 goto finish;
2360
2361 case MDEREF_INDEX_const:
2362 keysv = UNOP_AUX_item_sv(++items);
2363 break;
2364
2365 case MDEREF_INDEX_padsv:
2366 keysv = PAD_SVl((++items)->pad_offset);
2367 break;
2368
2369 case MDEREF_INDEX_gvsv:
2370 keysv = UNOP_AUX_item_sv(++items);
2371 keysv = GvSVn((GV*)keysv);
2372 break;
2373 }
2374
2375 /* see comment above about setting this var */
2376 PL_multideref_pc = items;
2377
2378
2379 /* ensure that candidate CONSTs have been HEKified */
2380 assert( ((actions & MDEREF_INDEX_MASK) != MDEREF_INDEX_const)
2381 || SvTYPE(keysv) >= SVt_PVMG
2382 || !SvOK(keysv)
2383 || SvROK(keysv)
2384 || SvIsCOW_shared_hash(keysv));
2385
2386 /* this is basically a copy of pp_helem with OPpDEREF skipped */
2387
2388 if (!(actions & MDEREF_FLAG_last)) {
2389 HE *he = hv_fetch_ent((HV*)sv, keysv, 1, 0);
2390 if (!he || !(sv=HeVAL(he)) || sv == &PL_sv_undef)
2391 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2392 break;
2393 }
2394
2395 if (PL_op->op_private &
2396 (OPpMULTIDEREF_EXISTS|OPpMULTIDEREF_DELETE))
2397 {
2398 if (PL_op->op_private & OPpMULTIDEREF_EXISTS) {
2399 sv = hv_exists_ent((HV*)sv, keysv, 0)
2400 ? &PL_sv_yes : &PL_sv_no;
2401 }
2402 else {
2403 I32 discard = (GIMME_V == G_VOID) ? G_DISCARD : 0;
2404 sv = hv_delete_ent((HV*)sv, keysv, discard, 0);
2405 if (discard)
2406 return NORMAL;
2407 if (!sv)
2408 sv = &PL_sv_undef;
2409 }
2410 }
2411 else {
2412 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
2413 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
2414 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
2415 bool preeminent = TRUE;
2416 SV **svp;
2417 HV * const hv = (HV*)sv;
2418 HE* he;
2419
2420 if (UNLIKELY(localizing)) {
2421 MAGIC *mg;
2422 HV *stash;
2423
2424 /* If we can determine whether the element exist,
2425 * Try to preserve the existenceness of a tied hash
2426 * element by using EXISTS and DELETE if possible.
2427 * Fallback to FETCH and STORE otherwise. */
2428 if (SvCANEXISTDELETE(hv))
2429 preeminent = hv_exists_ent(hv, keysv, 0);
2430 }
2431
2432 he = hv_fetch_ent(hv, keysv, lval && !defer, 0);
2433 svp = he ? &HeVAL(he) : NULL;
2434
2435
2436 if (lval) {
2437 if (!svp || !(sv = *svp) || sv == &PL_sv_undef) {
2438 SV* lv;
2439 SV* key2;
2440 if (!defer)
2441 DIE(aTHX_ PL_no_helem_sv, SVfARG(keysv));
2442 lv = sv_newmortal();
2443 sv_upgrade(lv, SVt_PVLV);
2444 LvTYPE(lv) = 'y';
2445 sv_magic(lv, key2 = newSVsv(keysv),
2446 PERL_MAGIC_defelem, NULL, 0);
2447 /* sv_magic() increments refcount */
2448 SvREFCNT_dec_NN(key2);
2449 LvTARG(lv) = SvREFCNT_inc_simple(hv);
2450 LvTARGLEN(lv) = 1;
2451 sv = lv;
2452 }
2453 else {
2454 if (localizing) {
2455 if (HvNAME_get(hv) && isGV(sv))
2456 save_gp(MUTABLE_GV(sv),
2457 !(PL_op->op_flags & OPf_SPECIAL));
2458 else if (preeminent) {
2459 save_helem_flags(hv, keysv, svp,
2460 (PL_op->op_flags & OPf_SPECIAL)
2461 ? 0 : SAVEf_SETMAGIC);
2462 sv = *svp; /* may have changed */
2463 }
2464 else
2465 SAVEHDELETE(hv, keysv);
2466 }
2467 }
2468 }
2469 else {
2470 sv = (svp && *svp ? *svp : &PL_sv_undef);
2471 /* see note in pp_helem() */
2472 if (SvRMAGICAL(hv) && SvGMAGICAL(sv))
2473 mg_get(sv);
2474 }
2475 }
2476 goto finish;
2477 }
2478
2479 } /* switch */
2480
2481 actions >>= MDEREF_SHIFT;
2482 } /* while */
2483 /* NOTREACHED */
2484}
2485
2486
a0d0e21e
LW
2487PP(pp_iter)
2488{
20b7effb 2489 dSP;
eb578fdb 2490 PERL_CONTEXT *cx;
7d6c2cef 2491 SV *oldsv;
1d7c1841 2492 SV **itersvp;
a0d0e21e 2493
924508f0 2494 EXTEND(SP, 1);
a0d0e21e 2495 cx = &cxstack[cxstack_ix];
1d7c1841 2496 itersvp = CxITERVAR(cx);
a48ce6be
DM
2497
2498 switch (CxTYPE(cx)) {
17c91640 2499
b552b52c
DM
2500 case CXt_LOOP_LAZYSV: /* string increment */
2501 {
2502 SV* cur = cx->blk_loop.state_u.lazysv.cur;
2503 SV *end = cx->blk_loop.state_u.lazysv.end;
2504 /* If the maximum is !SvOK(), pp_enteriter substitutes PL_sv_no.
2505 It has SvPVX of "" and SvCUR of 0, which is what we want. */
2506 STRLEN maxlen = 0;
2507 const char *max = SvPV_const(end, maxlen);
5d9574c1 2508 if (UNLIKELY(SvNIOK(cur) || SvCUR(cur) > maxlen))
b552b52c
DM
2509 RETPUSHNO;
2510
2511 oldsv = *itersvp;
5d9574c1 2512 if (LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
b552b52c
DM
2513 /* safe to reuse old SV */
2514 sv_setsv(oldsv, cur);
a48ce6be 2515 }
b552b52c
DM
2516 else
2517 {
2518 /* we need a fresh SV every time so that loop body sees a
2519 * completely new SV for closures/references to work as
2520 * they used to */
2521 *itersvp = newSVsv(cur);
fc2b2dca 2522 SvREFCNT_dec_NN(oldsv);
b552b52c
DM
2523 }
2524 if (strEQ(SvPVX_const(cur), max))
2525 sv_setiv(cur, 0); /* terminate next time */
2526 else
2527 sv_inc(cur);
2528 break;
2529 }
a48ce6be 2530
fcef60b4
DM
2531 case CXt_LOOP_LAZYIV: /* integer increment */
2532 {
2533 IV cur = cx->blk_loop.state_u.lazyiv.cur;
5d9574c1 2534 if (UNLIKELY(cur > cx->blk_loop.state_u.lazyiv.end))
89ea2908 2535 RETPUSHNO;
7f61b687 2536
fcef60b4 2537 oldsv = *itersvp;
3db8f154 2538 /* don't risk potential race */
5d9574c1 2539 if (LIKELY(SvREFCNT(oldsv) == 1 && !SvMAGICAL(oldsv))) {
eaa5c2d6 2540 /* safe to reuse old SV */
fcef60b4 2541 sv_setiv(oldsv, cur);
eaa5c2d6 2542 }
1c846c1f 2543 else
eaa5c2d6
GA
2544 {
2545 /* we need a fresh SV every time so that loop body sees a
2546 * completely new SV for closures/references to work as they
2547 * used to */
fcef60b4 2548 *itersvp = newSViv(cur);
fc2b2dca 2549 SvREFCNT_dec_NN(oldsv);
eaa5c2d6 2550 }
a2309040 2551
5d9574c1 2552 if (UNLIKELY(cur == IV_MAX)) {
cdc1aa42
NC
2553 /* Handle end of range at IV_MAX */
2554 cx->blk_loop.state_u.lazyiv.end = IV_MIN;
2555 } else
2556 ++cx->blk_loop.state_u.lazyiv.cur;
a48ce6be 2557 break;
fcef60b4 2558 }
a48ce6be 2559
b552b52c 2560 case CXt_LOOP_FOR: /* iterate array */
7d6c2cef 2561 {
89ea2908 2562
7d6c2cef
DM
2563 AV *av = cx->blk_loop.state_u.ary.ary;
2564 SV *sv;
2565 bool av_is_stack = FALSE;
a8a20bb6 2566 IV ix;
7d6c2cef 2567
de080daa
DM
2568 if (!av) {
2569 av_is_stack = TRUE;
2570 av = PL_curstack;
2571 }
2572 if (PL_op->op_private & OPpITER_REVERSED) {
a8a20bb6 2573 ix = --cx->blk_loop.state_u.ary.ix;
5d9574c1 2574 if (UNLIKELY(ix <= (av_is_stack ? cx->blk_loop.resetsp : -1)))
de080daa 2575 RETPUSHNO;
de080daa
DM
2576 }
2577 else {
a8a20bb6 2578 ix = ++cx->blk_loop.state_u.ary.ix;
5d9574c1 2579 if (UNLIKELY(ix > (av_is_stack ? cx->blk_oldsp : AvFILL(av))))
de080daa 2580 RETPUSHNO;
a8a20bb6 2581 }
de080daa 2582
5d9574c1 2583 if (UNLIKELY(SvMAGICAL(av) || AvREIFY(av))) {
a8a20bb6
DM
2584 SV * const * const svp = av_fetch(av, ix, FALSE);
2585 sv = svp ? *svp : NULL;
2586 }
2587 else {
2588 sv = AvARRAY(av)[ix];
de080daa 2589 }
ef3e5ea9 2590
d39c26a6
FC
2591 if (UNLIKELY(cx->cx_type & CXp_FOR_LVREF)) {
2592 SvSetMagicSV(*itersvp, sv);
2593 break;
2594 }
2595
5d9574c1
DM
2596 if (LIKELY(sv)) {
2597 if (UNLIKELY(SvIS_FREED(sv))) {
f38aa882
DM
2598 *itersvp = NULL;
2599 Perl_croak(aTHX_ "Use of freed value in iteration");
2600 }
60779a30 2601 if (SvPADTMP(sv)) {
8e079c2a 2602 sv = newSVsv(sv);
60779a30 2603 }
8e079c2a
FC
2604 else {
2605 SvTEMP_off(sv);
2606 SvREFCNT_inc_simple_void_NN(sv);
2607 }
de080daa 2608 }
a600f7e6 2609 else if (!av_is_stack) {
199f858d 2610 sv = newSVavdefelem(av, ix, 0);
de080daa 2611 }
a600f7e6
FC
2612 else
2613 sv = &PL_sv_undef;
a0d0e21e 2614
de080daa
DM
2615 oldsv = *itersvp;
2616 *itersvp = sv;
2617 SvREFCNT_dec(oldsv);
de080daa 2618 break;
7d6c2cef 2619 }
a48ce6be
DM
2620
2621 default:
2622 DIE(aTHX_ "panic: pp_iter, type=%u", CxTYPE(cx));
2623 }
b552b52c 2624 RETPUSHYES;
a0d0e21e
LW
2625}
2626
ef07e810
DM
2627/*
2628A description of how taint works in pattern matching and substitution.
2629
284167a5
SM
2630This is all conditional on NO_TAINT_SUPPORT not being defined. Under
2631NO_TAINT_SUPPORT, taint-related operations should become no-ops.
2632
4e19c54b 2633While the pattern is being assembled/concatenated and then compiled,
284167a5
SM
2634PL_tainted will get set (via TAINT_set) if any component of the pattern
2635is tainted, e.g. /.*$tainted/. At the end of pattern compilation,
2636the RXf_TAINTED flag is set on the pattern if PL_tainted is set (via
1738e041
DM
2637TAINT_get). It will also be set if any component of the pattern matches
2638based on locale-dependent behavior.
ef07e810 2639
0ab462a6
DM
2640When the pattern is copied, e.g. $r = qr/..../, the SV holding the ref to
2641the pattern is marked as tainted. This means that subsequent usage, such
284167a5
SM
2642as /x$r/, will set PL_tainted using TAINT_set, and thus RXf_TAINTED,
2643on the new pattern too.
ef07e810 2644
272d35c9 2645RXf_TAINTED_SEEN is used post-execution by the get magic code
ef07e810
DM
2646of $1 et al to indicate whether the returned value should be tainted.
2647It is the responsibility of the caller of the pattern (i.e. pp_match,
2648pp_subst etc) to set this flag for any other circumstances where $1 needs
2649to be tainted.
2650
2651The taint behaviour of pp_subst (and pp_substcont) is quite complex.
2652
2653There are three possible sources of taint
2654 * the source string
2655 * the pattern (both compile- and run-time, RXf_TAINTED / RXf_TAINTED_SEEN)
2656 * the replacement string (or expression under /e)
2657
2658There are four destinations of taint and they are affected by the sources
2659according to the rules below:
2660
2661 * the return value (not including /r):
2662 tainted by the source string and pattern, but only for the
2663 number-of-iterations case; boolean returns aren't tainted;
2664 * the modified string (or modified copy under /r):
2665 tainted by the source string, pattern, and replacement strings;
2666 * $1 et al:
2667 tainted by the pattern, and under 'use re "taint"', by the source
2668 string too;
2669 * PL_taint - i.e. whether subsequent code (e.g. in a /e block) is tainted:
2670 should always be unset before executing subsequent code.
2671
2672The overall action of pp_subst is:
2673
2674 * at the start, set bits in rxtainted indicating the taint status of
2675 the various sources.
2676
2677 * After each pattern execution, update the SUBST_TAINT_PAT bit in
2678 rxtainted if RXf_TAINTED_SEEN has been set, to indicate that the
2679 pattern has subsequently become tainted via locale ops.
2680
2681 * If control is being passed to pp_substcont to execute a /e block,
2682 save rxtainted in the CXt_SUBST block, for future use by
2683 pp_substcont.
2684
2685 * Whenever control is being returned to perl code (either by falling
2686 off the "end" of pp_subst/pp_substcont, or by entering a /e block),
2687 use the flag bits in rxtainted to make all the appropriate types of
0ab462a6
DM
2688 destination taint visible; e.g. set RXf_TAINTED_SEEN so that $1
2689 et al will appear tainted.
ef07e810
DM
2690
2691pp_match is just a simpler version of the above.
2692
2693*/
2694
a0d0e21e
LW
2695PP(pp_subst)
2696{
20b7effb 2697 dSP; dTARG;
eb578fdb 2698 PMOP *pm = cPMOP;
a0d0e21e 2699 PMOP *rpm = pm;
eb578fdb 2700 char *s;
a0d0e21e 2701 char *strend;
5c144d81 2702 const char *c;
a0d0e21e 2703 STRLEN clen;
3c6ef0a5
FC
2704 SSize_t iters = 0;
2705 SSize_t maxiters;
a0d0e21e 2706 bool once;
ef07e810
DM
2707 U8 rxtainted = 0; /* holds various SUBST_TAINT_* flag bits.
2708 See "how taint works" above */
a0d0e21e 2709 char *orig;
1ed74d04 2710 U8 r_flags;
eb578fdb 2711 REGEXP *rx = PM_GETRE(pm);
a0d0e21e
LW
2712 STRLEN len;
2713 int force_on_match = 0;
0bcc34c2 2714 const I32 oldsave = PL_savestack_ix;
792b2c16 2715 STRLEN slen;
26a74523 2716 bool doutf8 = FALSE; /* whether replacement is in utf8 */
db2c6cb3 2717#ifdef PERL_ANY_COW
ed252734
NC
2718 bool is_cow;
2719#endif
a0714e2c 2720 SV *nsv = NULL;
b770e143 2721 /* known replacement string? */
eb578fdb 2722 SV *dstr = (pm->op_pmflags & PMf_CONST) ? POPs : NULL;
a0d0e21e 2723
f410a211
NC
2724 PERL_ASYNC_CHECK();
2725
533c011a 2726 if (PL_op->op_flags & OPf_STACKED)
a0d0e21e 2727 TARG = POPs;
6ffceeb7 2728 else if (ARGTARG)
59f00321 2729 GETTARGET;
a0d0e21e 2730 else {
54b9620d 2731 TARG = DEFSV;
a0d0e21e 2732 EXTEND(SP,1);
1c846c1f 2733 }
d9f424b2 2734
64534138 2735 SvGETMAGIC(TARG); /* must come before cow check */
db2c6cb3 2736#ifdef PERL_ANY_COW
ed252734
NC
2737 /* Awooga. Awooga. "bool" types that are actually char are dangerous,
2738 because they make integers such as 256 "false". */
2739 is_cow = SvIsCOW(TARG) ? TRUE : FALSE;
2740#else
765f542d
NC
2741 if (SvIsCOW(TARG))
2742 sv_force_normal_flags(TARG,0);
ed252734 2743#endif
8ca8a454 2744 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)
8ca8a454
NC
2745 && (SvREADONLY(TARG)
2746 || ( ((SvTYPE(TARG) == SVt_PVGV && isGV_with_GP(TARG))
2747 || SvTYPE(TARG) > SVt_PVLV)
2748 && !(SvTYPE(TARG) == SVt_PVGV && SvFAKE(TARG)))))
cb077ed2 2749 Perl_croak_no_modify();
8ec5e241
NIS
2750 PUTBACK;
2751
6ac6605d
DM
2752 orig = SvPV_nomg(TARG, len);
2753 /* note we don't (yet) force the var into being a string; if we fail
2754 * to match, we leave as-is; on successful match howeverm, we *will*
2755 * coerce into a string, then repeat the match */
4499db73 2756 if (!SvPOKp(TARG) || SvTYPE(TARG) == SVt_PVGV || SvVOK(TARG))
a0d0e21e 2757 force_on_match = 1;
20be6587
DM
2758
2759 /* only replace once? */
2760 once = !(rpm->op_pmflags & PMf_GLOBAL);
2761
ef07e810 2762 /* See "how taint works" above */
284167a5 2763 if (TAINTING_get) {
20be6587
DM
2764 rxtainted = (
2765 (SvTAINTED(TARG) ? SUBST_TAINT_STR : 0)
284167a5 2766 | (RX_ISTAINTED(rx) ? SUBST_TAINT_PAT : 0)
20be6587
DM
2767 | ((pm->op_pmflags & PMf_RETAINT) ? SUBST_TAINT_RETAINT : 0)
2768 | ((once && !(rpm->op_pmflags & PMf_NONDESTRUCT))
2769 ? SUBST_TAINT_BOOLRET : 0));
2770 TAINT_NOT;
2771 }
a12c0f56 2772
a0d0e21e 2773 force_it:
6ac6605d
DM
2774 if (!pm || !orig)
2775 DIE(aTHX_ "panic: pp_subst, pm=%p, orig=%p", pm, orig);
a0d0e21e 2776
6ac6605d
DM
2777 strend = orig + len;
2778 slen = DO_UTF8(TARG) ? utf8_length((U8*)orig, (U8*)strend) : len;
792b2c16
JH
2779 maxiters = 2 * slen + 10; /* We can match twice at each
2780 position, once with zero-length,
2781 second time with non-zero. */
a0d0e21e 2782
6a97c51d 2783 if (!RX_PRELEN(rx) && PL_curpm
8d919b0a 2784 && !ReANY(rx)->mother_re) {
3280af22 2785 pm = PL_curpm;
aaa362c4 2786 rx = PM_GETRE(pm);
a0d0e21e 2787 }
6502e081 2788
6e240d0b 2789#ifdef PERL_SAWAMPERSAND
6502e081
DM
2790 r_flags = ( RX_NPARENS(rx)
2791 || PL_sawampersand
6502e081 2792 || (RX_EXTFLAGS(rx) & (RXf_EVAL_SEEN|RXf_PMf_KEEPCOPY))
5b0e71e9 2793 || (rpm->op_pmflags & PMf_KEEPCOPY)
6502e081
DM
2794 )
2795 ? REXEC_COPY_STR
2796 : 0;
6e240d0b
FC
2797#else
2798 r_flags = REXEC_COPY_STR;
2799#endif
7fba1cd6 2800
0395280b 2801 if (!CALLREGEXEC(rx, orig, strend, orig, 0, TARG, NULL, r_flags))
8b64c330 2802 {
5e79dfb9
DM
2803 SPAGAIN;
2804 PUSHs(rpm->op_pmflags & PMf_NONDESTRUCT ? TARG : &PL_sv_no);
2805 LEAVE_SCOPE(oldsave);
2806 RETURN;
2807 }
1754320d
FC
2808 PL_curpm = pm;
2809
71be2cbc 2810 /* known replacement string? */
f272994b 2811 if (dstr) {
8514a05a
JH
2812 /* replacement needing upgrading? */
2813 if (DO_UTF8(TARG) && !doutf8) {
db79b45b 2814 nsv = sv_newmortal();
4a176938 2815 SvSetSV(nsv, dstr);
47e13f24 2816 if (IN_ENCODING)
ad2de1b2 2817 sv_recode_to_utf8(nsv, _get_encoding());
8514a05a
JH
2818 else
2819 sv_utf8_upgrade(nsv);
5c144d81 2820 c = SvPV_const(nsv, clen);
4a176938
JH
2821 doutf8 = TRUE;
2822 }
2823 else {
5c144d81 2824 c = SvPV_const(dstr, clen);
4a176938 2825 doutf8 = DO_UTF8(dstr);
8514a05a 2826 }
bb933b9b
FC
2827
2828 if (SvTAINTED(dstr))
2829 rxtainted |= SUBST_TAINT_REPL;
f272994b
A
2830 }
2831 else {
6136c704 2832 c = NULL;
f272994b
A
2833 doutf8 = FALSE;
2834 }
2835
71be2cbc 2836 /* can do inplace substitution? */
ed252734 2837 if (c
db2c6cb3 2838#ifdef PERL_ANY_COW
ed252734
NC
2839 && !is_cow
2840#endif
fbfb1899 2841 && (I32)clen <= RX_MINLENRET(rx)
9cefd268
FC
2842 && ( once
2843 || !(r_flags & REXEC_COPY_STR)
2844 || (!SvGMAGICAL(dstr) && !(RX_EXTFLAGS(rx) & RXf_EVAL_SEEN))
2845 )
dbc200c5 2846 && !(RX_EXTFLAGS(rx) & RXf_NO_INPLACE_SUBST)
8ca8a454
NC
2847 && (!doutf8 || SvUTF8(TARG))
2848 && !(rpm->op_pmflags & PMf_NONDESTRUCT))
8b030b38 2849 {
ec911639 2850
db2c6cb3 2851#ifdef PERL_ANY_COW
ed252734 2852 if (SvIsCOW(TARG)) {
f7a8268c 2853 if (!force_on_match)
ed252734 2854 goto have_a_cow;
f7a8268c 2855 assert(SvVOK(TARG));
ed252734
NC
2856 }
2857#endif
71be2cbc 2858 if (force_on_match) {
6ac6605d
DM
2859 /* redo the first match, this time with the orig var
2860 * forced into being a string */
71be2cbc 2861 force_on_match = 0;
6ac6605d 2862 orig = SvPV_force_nomg(TARG, len);
71be2cbc
PP
2863 goto force_it;
2864 }
39b40493 2865
71be2cbc 2866 if (once) {
c67ab8f2 2867 char *d, *m;
20be6587
DM
2868 if (RX_MATCH_TAINTED(rx)) /* run time pattern taint, eg locale */
2869 rxtainted |= SUBST_TAINT_PAT;
07bc277f
NC
2870 m = orig + RX_OFFS(rx)[0].start;
2871 d = orig + RX_OFFS(rx)[0].end;
71be2cbc
PP
2872 s = orig;
2873 if (m - s > strend - d) { /* faster to shorten from end */
2ec7214c 2874 I32 i;
71be2cbc
PP
2875 if (clen) {
2876 Copy(c, m, clen, char);
2877 m += clen;
a0d0e21e 2878 }
71be2cbc
PP
2879 i = strend - d;
2880 if (i > 0) {
2881 Move(d, m, i, char);
2882 m += i;
a0d0e21e 2883 }
71be2cbc
PP
2884 *m = '\0';
2885 SvCUR_set(TARG, m - s);
2886 }
2ec7214c
DM
2887 else { /* faster from front */
2888 I32 i = m - s;
71be2cbc 2889 d -= clen;
2ec7214c
DM
2890 if (i > 0)
2891 Move(s, d - i, i, char);
71be2cbc 2892 sv_chop(TARG, d-i);
71be2cbc 2893 if (clen)
c947cd8d 2894 Copy(c, d, clen, char);
71be2cbc 2895 }
8ec5e241 2896 SPAGAIN;
8ca8a454 2897 PUSHs(&PL_sv_yes);
71be2cbc
PP
2898 }
2899 else {
c67ab8f2 2900 char *d, *m;
0395280b 2901 d = s = RX_OFFS(rx)[0].start + orig;
71be2cbc 2902 do {
2b25edcf 2903 I32 i;
5d9574c1 2904 if (UNLIKELY(iters++ > maxiters))
cea2e8a9 2905 DIE(aTHX_ "Substitution loop");
5d9574c1 2906 if (UNLIKELY(RX_MATCH_TAINTED(rx))) /* run time pattern taint, eg locale */
20be6587 2907 rxtainted |= SUBST_TAINT_PAT;
07bc277f 2908 m = RX_OFFS(rx)[0].start + orig;
155aba94 2909 if ((i = m - s)) {
71be2cbc
PP
2910 if (s != d)
2911 Move(s, d, i, char);
2912 d += i;
a0d0e21e 2913 }
71be2cbc
PP
2914 if (clen) {
2915 Copy(c, d, clen, char);
2916 d += clen;
2917 }
07bc277f 2918 s = RX_OFFS(rx)[0].end + orig;
7ce41e5c
FC
2919 } while (CALLREGEXEC(rx, s, strend, orig,
2920 s == m, /* don't match same null twice */
f722798b 2921 TARG, NULL,
d5e7783a 2922 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
71be2cbc 2923 if (s != d) {
2b25edcf 2924 I32 i = strend - s;
aa07b2f6 2925 SvCUR_set(TARG, d - SvPVX_const(TARG) + i);
71be2cbc 2926 Move(s, d, i+1, char); /* include the NUL */
a0d0e21e 2927 }
8ec5e241 2928 SPAGAIN;
3c6ef0a5 2929 mPUSHi(iters);
a0d0e21e
LW
2930 }
2931 }
ff6e92e8 2932 else {
1754320d 2933 bool first;
c67ab8f2 2934 char *m;
1754320d 2935 SV *repl;
a0d0e21e 2936 if (force_on_match) {
6ac6605d
DM
2937 /* redo the first match, this time with the orig var
2938 * forced into being a string */
a0d0e21e 2939 force_on_match = 0;
0c1438a1
NC
2940 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
2941 /* I feel that it should be possible to avoid this mortal copy
2942 given that the code below copies into a new destination.
2943 However, I suspect it isn't worth the complexity of
2944 unravelling the C<goto force_it> for the small number of
2945 cases where it would be viable to drop into the copy code. */
2946 TARG = sv_2mortal(newSVsv(TARG));
2947 }
6ac6605d 2948 orig = SvPV_force_nomg(TARG, len);
a0d0e21e
LW
2949 goto force_it;
2950 }
db2c6cb3 2951#ifdef PERL_ANY_COW
ed252734
NC
2952 have_a_cow:
2953#endif
20be6587
DM
2954 if (RX_MATCH_TAINTED(rx)) /* run time pattern taint, eg locale */
2955 rxtainted |= SUBST_TAINT_PAT;
1754320d 2956 repl = dstr;
0395280b
DM
2957 s = RX_OFFS(rx)[0].start + orig;
2958 dstr = newSVpvn_flags(orig, s-orig,
2959 SVs_TEMP | (DO_UTF8(TARG) ? SVf_UTF8 : 0));
a0d0e21e 2960 if (!c) {
eb578fdb 2961 PERL_CONTEXT *cx;
8ec5e241 2962 SPAGAIN;
0395280b 2963 m = orig;
20be6587
DM
2964 /* note that a whole bunch of local vars are saved here for
2965 * use by pp_substcont: here's a list of them in case you're
2966 * searching for places in this sub that uses a particular var:
2967 * iters maxiters r_flags oldsave rxtainted orig dstr targ
2968 * s m strend rx once */
a0d0e21e 2969 PUSHSUBST(cx);
20e98b0f 2970 RETURNOP(cPMOP->op_pmreplrootu.op_pmreplroot);
a0d0e21e 2971 }
1754320d 2972 first = TRUE;
a0d0e21e 2973 do {
5d9574c1 2974 if (UNLIKELY(iters++ > maxiters))
cea2e8a9 2975 DIE(aTHX_ "Substitution loop");
5d9574c1 2976 if (UNLIKELY(RX_MATCH_TAINTED(rx)))
20be6587 2977 rxtainted |= SUBST_TAINT_PAT;
07bc277f 2978 if (RX_MATCH_COPIED(rx) && RX_SUBBEG(rx) != orig) {
c67ab8f2
DM
2979 char *old_s = s;
2980 char *old_orig = orig;
6502e081 2981 assert(RX_SUBOFFSET(rx) == 0);
c67ab8f2 2982
07bc277f 2983 orig = RX_SUBBEG(rx);
c67ab8f2
DM
2984 s = orig + (old_s - old_orig);
2985 strend = s + (strend - old_s);
a0d0e21e 2986 }
07bc277f 2987 m = RX_OFFS(rx)[0].start + orig;
64534138 2988 sv_catpvn_nomg_maybeutf8(dstr, s, m - s, DO_UTF8(TARG));
07bc277f 2989 s = RX_OFFS(rx)[0].end + orig;
1754320d
FC
2990 if (first) {
2991 /* replacement already stringified */
2992 if (clen)
64534138 2993 sv_catpvn_nomg_maybeutf8(dstr, c, clen, doutf8);
1754320d
FC
2994 first = FALSE;
2995 }
2996 else {
47e13f24 2997 if (IN_ENCODING) {
1754320d
FC
2998 if (!nsv) nsv = sv_newmortal();
2999 sv_copypv(nsv, repl);
ad2de1b2 3000 if (!DO_UTF8(nsv)) sv_recode_to_utf8(nsv, _get_encoding());
1754320d
FC
3001 sv_catsv(dstr, nsv);
3002 }
3003 else sv_catsv(dstr, repl);
5d9574c1 3004 if (UNLIKELY(SvTAINTED(repl)))
bb933b9b 3005 rxtainted |= SUBST_TAINT_REPL;
1754320d 3006 }
a0d0e21e
LW
3007 if (once)
3008 break;
f9f4320a 3009 } while (CALLREGEXEC(rx, s, strend, orig, s == m,
d5e7783a
DM
3010 TARG, NULL,
3011 REXEC_NOT_FIRST|REXEC_IGNOREPOS|REXEC_FAIL_ON_UNDERFLOW));
64534138 3012 sv_catpvn_nomg_maybeutf8(dstr, s, strend - s, DO_UTF8(TARG));
748a9306 3013
8ca8a454
NC
3014 if (rpm->op_pmflags & PMf_NONDESTRUCT) {
3015 /* From here on down we're using the copy, and leaving the original
3016 untouched. */
3017 TARG = dstr;
3018 SPAGAIN;
3019 PUSHs(dstr);
3020 } else {
db2c6cb3 3021#ifdef PERL_ANY_COW
8ca8a454
NC
3022 /* The match may make the string COW. If so, brilliant, because
3023 that's just saved us one malloc, copy and free - the regexp has
3024 donated the old buffer, and we malloc an entirely new one, rather
3025 than the regexp malloc()ing a buffer and copying our original,
3026 only for us to throw it away here during the substitution. */
3027 if (SvIsCOW(TARG)) {
3028 sv_force_normal_flags(TARG, SV_COW_DROP_PV);
3029 } else
ed252734 3030#endif
8ca8a454
NC
3031 {
3032 SvPV_free(TARG);
3033 }
3034 SvPV_set(TARG, SvPVX(dstr));
3035 SvCUR_set(TARG, SvCUR(dstr));
3036 SvLEN_set(TARG, SvLEN(dstr));
64534138 3037 SvFLAGS(TARG) |= SvUTF8(dstr);
8ca8a454 3038 SvPV_set(dstr, NULL);
748a9306 3039
8ca8a454 3040 SPAGAIN;
3c6ef0a5 3041 mPUSHi(iters);
8ca8a454
NC
3042 }
3043 }
3044
3045 if (!(rpm->op_pmflags & PMf_NONDESTRUCT)) {
3046 (void)SvPOK_only_UTF8(TARG);
a0d0e21e 3047 }
20be6587 3048
ef07e810 3049 /* See "how taint works" above */
284167a5 3050 if (TAINTING_get) {
20be6587
DM
3051 if ((rxtainted & SUBST_TAINT_PAT) ||
3052 ((rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_RETAINT)) ==
3053 (SUBST_TAINT_STR|SUBST_TAINT_RETAINT))
3054 )
3055 (RX_MATCH_TAINTED_on(rx)); /* taint $1 et al */
3056
3057 if (!(rxtainted & SUBST_TAINT_BOOLRET)
3058 && (rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT))
3059 )
3060 SvTAINTED_on(TOPs); /* taint return value */
3061 else
3062 SvTAINTED_off(TOPs); /* may have got tainted earlier */
3063
3064 /* needed for mg_set below */
284167a5
SM
3065 TAINT_set(
3066 cBOOL(rxtainted & (SUBST_TAINT_STR|SUBST_TAINT_PAT|SUBST_TAINT_REPL))
3067 );
20be6587
DM
3068 SvTAINT(TARG);
3069 }
3070 SvSETMAGIC(TARG); /* PL_tainted must be correctly set for this mg_set */
3071 TAINT_NOT;
f1a76097
DM
3072 LEAVE_SCOPE(oldsave);
3073 RETURN;
a0d0e21e
LW
3074}
3075
3076PP(pp_grepwhile)
3077{
20b7effb 3078 dSP;
a0d0e21e
LW
3079
3080 if (SvTRUEx(POPs))
3280af22
NIS
3081 PL_stack_base[PL_markstack_ptr[-1]++] = PL_stack_base[*PL_markstack_ptr];
3082 ++*PL_markstack_ptr;
b2a2a901 3083 FREETMPS;
d343c3ef 3084 LEAVE_with_name("grep_item"); /* exit inner scope */
a0d0e21e
LW
3085
3086 /* All done yet? */
5d9574c1 3087 if (UNLIKELY(PL_stack_base + *PL_markstack_ptr > SP)) {
a0d0e21e 3088 I32 items;
c4420975 3089 const I32 gimme = GIMME_V;
a0d0e21e 3090
d343c3ef 3091 LEAVE_with_name("grep"); /* exit outer scope */
a0d0e21e 3092 (void)POPMARK; /* pop src */
3280af22 3093 items = --*PL_markstack_ptr - PL_markstack_ptr[-1];
a0d0e21e 3094 (void)POPMARK; /* pop dst */
3280af22 3095 SP = PL_stack_base + POPMARK; /* pop original mark */
54310121 3096 if (gimme == G_SCALAR) {
7cc47870 3097 if (PL_op->op_private & OPpGREP_LEX) {
c4420975 3098 SV* const sv = sv_newmortal();
7cc47870
RGS
3099 sv_setiv(sv, items);
3100 PUSHs(sv);
3101 }
3102 else {
3103 dTARGET;
3104 XPUSHi(items);
3105 }
a0d0e21e 3106 }
54310121
PP
3107 else if (gimme == G_ARRAY)
3108 SP += items;
a0d0e21e
LW
3109 RETURN;
3110 }
3111 else {
3112 SV *src;
3113
d343c3ef 3114 ENTER_with_name("grep_item"); /* enter inner scope */
1d7c1841 3115 SAVEVPTR(PL_curpm);
a0d0e21e 3116
3280af22 3117 src = PL_stack_base[*PL_markstack_ptr];
60779a30 3118 if (SvPADTMP(src)) {
a0ed822e
FC
3119 src = PL_stack_base[*PL_markstack_ptr] = sv_mortalcopy(src);
3120 PL_tmps_floor++;
3121 }
a0d0e21e 3122 SvTEMP_off(src);
59f00321
RGS
3123 if (PL_op->op_private & OPpGREP_LEX)
3124 PAD_SVl(PL_op->op_targ) = src;
3125 else
414bf5ae 3126 DEFSV_set(src);
a0d0e21e
LW
3127
3128 RETURNOP(cLOGOP->op_other);
3129 }
3130}
3131
3132PP(pp_leavesub)
3133{
20b7effb 3134 dSP;
a0d0e21e
LW
3135 SV **mark;
3136 SV **newsp;
3137 PMOP *newpm;
3138 I32 gimme;
eb578fdb 3139 PERL_CONTEXT *cx;
b0d9ce38 3140 SV *sv;
a0d0e21e 3141
1f0ba93b
DM
3142 if (CxMULTICALL(&cxstack[cxstack_ix])) {
3143 /* entry zero of a stack is always PL_sv_undef, which
3144 * simplifies converting a '()' return into undef in scalar context */
3145 assert(PL_stack_sp > PL_stack_base || *PL_stack_base == &PL_sv_undef);
9850bf21 3146 return 0;
1f0ba93b 3147 }
9850bf21 3148
a0d0e21e 3149 POPBLOCK(cx,newpm);
5dd42e15 3150 cxstack_ix++; /* temporarily protect top context */
1c846c1f 3151
a1f49e72 3152 TAINT_NOT;
a0d0e21e
LW
3153 if (gimme == G_SCALAR) {
3154 MARK = newsp + 1;
5d9574c1 3155 if (LIKELY(MARK <= SP)) {
a8bba7fa 3156 if (cx->blk_sub.cv && CvDEPTH(cx->blk_sub.cv) > 1) {
6f48390a
FC
3157 if (SvTEMP(TOPs) && SvREFCNT(TOPs) == 1
3158 && !SvMAGICAL(TOPs)) {
a29cdaf0
IZ
3159 *MARK = SvREFCNT_inc(TOPs);
3160 FREETMPS;
3161 sv_2mortal(*MARK);
cd06dffe
GS
3162 }
3163 else {
959e3673 3164 sv = SvREFCNT_inc(TOPs); /* FREETMPS could clobber it */
a29cdaf0 3165 FREETMPS;
959e3673 3166 *MARK = sv_mortalcopy(sv);
fc2b2dca 3167 SvREFCNT_dec_NN(sv);
a29cdaf0 3168 }
cd06dffe 3169 }
6f48390a
FC
3170 else if (SvTEMP(TOPs) && SvREFCNT(TOPs) == 1
3171 && !SvMAGICAL(TOPs)) {
767eda44 3172 *MARK = TOPs;
767eda44 3173 }
cd06dffe 3174 else
767eda44 3175 *MARK = sv_mortalcopy(TOPs);
cd06dffe
GS
3176 }
3177 else {
f86702cc 3178 MEXTEND(MARK, 0);
3280af22 3179 *MARK = &PL_sv_undef;
a0d0e21e
LW
3180 }
3181 SP = MARK;
3182 }
54310121 3183 else if (gimme == G_ARRAY) {
f86702cc 3184 for (MARK = newsp + 1; MARK <= SP; MARK++) {
6f48390a
FC
3185 if (!SvTEMP(*MARK) || SvREFCNT(*MARK) != 1
3186 || SvMAGICAL(*MARK)) {
f86702cc 3187 *MARK = sv_mortalcopy(*MARK);
a1f49e72
CS
3188 TAINT_NOT; /* Each item is independent */
3189 }
f86702cc 3190 }
a0d0e21e 3191 }
f86702cc 3192 PUTBACK;
1c846c1f 3193
a57c6685 3194 LEAVE;
b0d9ce38 3195 POPSUB(cx,sv); /* Stack values are safe: release CV and @_ ... */
25375124 3196 cxstack_ix--;
3280af22 3197 PL_curpm = newpm; /* ... and pop $1 et al */
a0d0e21e 3198
b0d9ce38 3199 LEAVESUB(sv);
f39bc417 3200 return cx->blk_sub.retop;
a0d0e21e
LW
3201}
3202
3203PP(pp_entersub)
3204{
20b7effb 3205 dSP; dPOPss;
a0d0e21e 3206 GV *gv;
eb578fdb
KW
3207 CV *cv;
3208 PERL_CONTEXT *cx;
5d94fbed 3209 I32 gimme;
a9c4fd4e 3210 const bool hasargs = (PL_op->op_flags & OPf_STACKED) != 0;
a0d0e21e 3211
f5719c02 3212 if (UNLIKELY(!sv))
cea2e8a9 3213 DIE(aTHX_ "Not a CODE reference");
f5719c02
DM
3214 /* This is overwhelmingly the most common case: */
3215 if (!LIKELY(SvTYPE(sv) == SVt_PVGV && (cv = GvCVu((const GV *)sv)))) {
313107ce
DM
3216 switch (SvTYPE(sv)) {
3217 case SVt_PVGV:
3218 we_have_a_glob:
3219 if (!(cv = GvCVu((const GV *)sv))) {
3220 HV *stash;
3221 cv = sv_2cv(sv, &stash, &gv, 0);
3222 }
3223 if (!cv) {
3224 ENTER;
3225 SAVETMPS;
3226 goto try_autoload;
3227 }
3228 break;
3229 case SVt_PVLV:
3230 if(isGV_with_GP(sv)) goto we_have_a_glob;
924ba076 3231 /* FALLTHROUGH */
313107ce
DM
3232 default:
3233 if (sv == &PL_sv_yes) { /* unfound import, ignore */
3234 if (hasargs)
3235 SP = PL_stack_base + POPMARK;
3236 else
3237 (void)POPMARK;
3238 RETURN;
3239 }
3240 SvGETMAGIC(sv);
3241 if (SvROK(sv)) {
3242 if (SvAMAGIC(sv)) {
3243 sv = amagic_deref_call(sv, to_cv_amg);
3244 /* Don't SPAGAIN here. */
3245 }
3246 }
3247 else {
3248 const char *sym;
3249 STRLEN len;
3250 if (!SvOK(sv))
3251 DIE(aTHX_ PL_no_usym, "a subroutine");
3252 sym = SvPV_nomg_const(sv, len);
3253 if (PL_op->op_private & HINT_STRICT_REFS)
3254 DIE(aTHX_ "Can't use string (\"%" SVf32 "\"%s) as a subroutine ref while \"strict refs\" in use", sv, len>32 ? "..." : "");
3255 cv = get_cvn_flags(sym, len, GV_ADD|SvUTF8(sv));
3256 break;
3257 }
3258 cv = MUTABLE_CV(SvRV(sv));
3259 if (SvTYPE(cv) == SVt_PVCV)
3260 break;
924ba076 3261 /* FALLTHROUGH */
313107ce
DM
3262 case SVt_PVHV:
3263 case SVt_PVAV:
3264 DIE(aTHX_ "Not a CODE reference");
3265 /* This is the second most common case: */
3266 case SVt_PVCV:
3267 cv = MUTABLE_CV(sv);
3268 break;
3269 }
f5719c02 3270 }
a0d0e21e 3271
a57c6685 3272 ENTER;
a0d0e21e
LW
3273
3274 retry:
f5719c02 3275 if (UNLIKELY(CvCLONE(cv) && ! CvCLONED(cv)))
541ed3a9 3276 DIE(aTHX_ "Closure prototype called");
f5719c02 3277 if (UNLIKELY(!CvROOT(cv) && !CvXSUB(cv))) {
2f349aa0
NC
3278 GV* autogv;
3279 SV* sub_name;
3280
3281 /* anonymous or undef'd function leaves us no recourse */
ae77754a
FC
3282 if (CvLEXICAL(cv) && CvHASGV(cv))
3283 DIE(aTHX_ "Undefined subroutine &%"SVf" called",
ecf05a58 3284 SVfARG(cv_name(cv, NULL, 0)));
ae77754a 3285 if (CvANON(cv) || !CvHASGV(cv)) {
2f349aa0 3286 DIE(aTHX_ "Undefined subroutine called");
7d2057d8 3287 }
2f349aa0
NC
3288
3289 /* autoloaded stub? */
ae77754a 3290 if (cv != GvCV(gv = CvGV(cv))) {
2f349aa0
NC
3291 cv = GvCV(gv);
3292 }
3293 /* should call AUTOLOAD now? */
3294 else {
7b52d656 3295 try_autoload:
d1089224
BF
3296 if ((autogv = gv_autoload_pvn(GvSTASH(gv), GvNAME(gv), GvNAMELEN(gv),
3297 GvNAMEUTF8(gv) ? SVf_UTF8 : 0)))
2f349aa0
NC
3298 {
3299 cv = GvCV(autogv);
3300 }
2f349aa0 3301 else {
c220e1a1 3302 sorry:
2f349aa0 3303 sub_name = sv_newmortal();
6136c704 3304 gv_efullname3(sub_name, gv, NULL);
be2597df 3305 DIE(aTHX_ "Undefined subroutine &%"SVf" called", SVfARG(sub_name));
2f349aa0
NC
3306 }
3307 }
3308 if (!cv)
c220e1a1 3309 goto sorry;
2f349aa0 3310 goto retry;
a0d0e21e
LW
3311 }
3312
f5719c02
DM
3313 if (UNLIKELY((PL_op->op_private & OPpENTERSUB_DB) && GvCV(PL_DBsub)
3314 && !CvNODEBUG(cv)))
3315 {
005a8a35 3316 Perl_get_db_sub(aTHX_ &sv, cv);
a9ef256d
NC
3317 if (CvISXSUB(cv))
3318 PL_curcopdb = PL_curcop;
1ad62f64 3319 if (CvLVALUE(cv)) {
3320 /* check for lsub that handles lvalue subroutines */
07b605e5 3321 cv = GvCV(gv_fetchpvs("DB::lsub", GV_ADDMULTI, SVt_PVCV));
1ad62f64 3322 /* if lsub not found then fall back to DB::sub */
3323 if (!cv) cv = GvCV(PL_DBsub);
3324 } else {
3325 cv = GvCV(PL_DBsub);
3326 }
a9ef256d 3327
ccafdc96
RGS
3328 if (!cv || (!CvXSUB(cv) && !CvSTART(cv)))
3329 DIE(aTHX_ "No DB::sub routine defined");
67caa1fe 3330 }
a0d0e21e 3331
f5719c02
DM
3332 gimme = GIMME_V;
3333
aed2304a 3334 if (!(CvISXSUB(cv))) {
f1025168 3335 /* This path taken at least 75% of the time */
a0d0e21e 3336 dMARK;
b70d5558 3337 PADLIST * const padlist = CvPADLIST(cv);
3689ad62 3338 I32 depth;
f5719c02 3339
a0d0e21e
LW
3340 PUSHBLOCK(cx, CXt_SUB, MARK);
3341 PUSHSUB(cx);
f39bc417 3342 cx->blk_sub.retop = PL_op->op_next;
3689ad62 3343 if (UNLIKELY((depth = ++CvDEPTH(cv)) >= 2)) {
3a76ca88 3344 PERL_STACK_OVERFLOW_CHECK();
3689ad62 3345 pad_push(padlist, depth);
a0d0e21e 3346 }
3a76ca88 3347 SAVECOMPPAD();
3689ad62 3348 PAD_SET_CUR_NOSAVE(padlist, depth);
f5719c02 3349 if (LIKELY(hasargs)) {
10533ace 3350 AV *const av = MUTABLE_AV(PAD_SVl(0));
bdf02c57
DM
3351 SSize_t items;
3352 AV **defavp;
3353
f5719c02 3354 if (UNLIKELY(AvREAL(av))) {
221373f0
GS
3355 /* @_ is normally not REAL--this should only ever
3356 * happen when DB::sub() calls things that modify @_ */
3357 av_clear(av);
3358 AvREAL_off(av);
3359 AvREIFY_on(av);
3360 }
bdf02c57
DM
3361 defavp = &GvAV(PL_defgv);
3362 cx->blk_sub.savearray = *defavp;
3363 *defavp = MUTABLE_AV(SvREFCNT_inc_simple_NN(av));
dd2155a4 3364 CX_CURPAD_SAVE(cx->blk_sub);
6d4ff0d2 3365 cx->blk_sub.argarray = av;
bdf02c57 3366 items = SP - MARK;
a0d0e21e 3367
f5719c02 3368 if (UNLIKELY(items - 1 > AvMAX(av))) {
77d27ef6
SF
3369 SV **ary = AvALLOC(av);
3370 AvMAX(av) = items - 1;
3371 Renew(ary, items, SV*);
3372 AvALLOC(av) = ary;
3373 AvARRAY(av) = ary;
3374 }
3375
bdf02c57 3376 Copy(MARK+1,AvARRAY(av),items,SV*);
93965878 3377 AvFILLp(av) = items - 1;
1c846c1f 3378
b479c9f2 3379 MARK = AvARRAY(av);
a0d0e21e
LW
3380 while (items--) {
3381 if (*MARK)
b479c9f2 3382 {
60779a30 3383 if (SvPADTMP(*MARK)) {
b479c9f2 3384 *MARK = sv_mortalcopy(*MARK);
60779a30 3385 }
a0d0e21e 3386 SvTEMP_off(*MARK);
b479c9f2 3387 }
a0d0e21e
LW
3388 MARK++;
3389 }
3390 }
b479c9f2 3391 SAVETMPS;
f5719c02
DM
3392 if (UNLIKELY((cx->blk_u16 & OPpENTERSUB_LVAL_MASK) == OPpLVAL_INTRO &&
3393 !CvLVALUE(cv)))
da1dff94 3394 DIE(aTHX_ "Can't modify non-lvalue subroutine call");
4a925ff6
GS
3395 /* warning must come *after* we fully set up the context
3396 * stuff so that __WARN__ handlers can safely dounwind()
3397 * if they want to
3398 */
3689ad62 3399 if (UNLIKELY(depth == PERL_SUB_DEPTH_WARN
f5719c02
DM
3400 && ckWARN(WARN_RECURSION)
3401 && !(PERLDB_SUB && cv == GvCV(PL_DBsub))))
4a925ff6 3402 sub_crush_depth(cv);
a0d0e21e
LW
3403 RETURNOP(CvSTART(cv));
3404 }
f1025168 3405 else {
de935cc9 3406 SSize_t markix = TOPMARK;
f1025168 3407
b479c9f2 3408 SAVETMPS;
3a76ca88 3409 PUTBACK;
f1025168 3410
f5719c02 3411 if (UNLIKELY(((PL_op->op_private
4587c532
FC
3412 & PUSHSUB_GET_LVALUE_MASK(Perl_is_lvalue_sub)
3413 ) & OPpENTERSUB_LVAL_MASK) == OPpLVAL_INTRO &&
f5719c02 3414 !CvLVALUE(cv)))
4587c532
FC
3415 DIE(aTHX_ "Can't modify non-lvalue subroutine call");
3416
f5719c02 3417 if (UNLIKELY(!hasargs && GvAV(PL_defgv))) {
3a76ca88
RGS
3418 /* Need to copy @_ to stack. Alternative may be to
3419 * switch stack to @_, and copy return values
3420 * back. This would allow popping @_ in XSUB, e.g.. XXXX */
3421 AV * const av = GvAV(PL_defgv);
ad39f3a2 3422 const SSize_t items = AvFILL(av) + 1;
3a76ca88
RGS
3423
3424 if (items) {
dd2a7f90 3425 SSize_t i = 0;
ad39f3a2 3426 const bool m = cBOOL(SvRMAGICAL(av));
3a76ca88
RGS
3427 /* Mark is at the end of the stack. */
3428 EXTEND(SP, items);
dd2a7f90 3429 for (; i < items; ++i)
ad39f3a2
FC
3430 {
3431 SV *sv;
3432 if (m) {
3433 SV ** const svp = av_fetch(av, i, 0);
3434 sv = svp ? *svp : NULL;
3435 }
3436 else sv = AvARRAY(av)[i];
3437 if (sv) SP[i+1] = sv;
dd2a7f90 3438 else {
199f858d 3439 SP[i+1] = newSVavdefelem(av, i, 1);
dd2a7f90 3440 }
ad39f3a2 3441 }
3a76ca88
RGS
3442 SP += items;
3443 PUTBACK ;
3444 }
3445 }
3455055f
FC
3446 else {
3447 SV **mark = PL_stack_base + markix;
de935cc9 3448 SSize_t items = SP - mark;
3455055f
FC
3449 while (items--) {
3450 mark++;
60779a30 3451 if (*mark && SvPADTMP(*mark)) {
3455055f 3452 *mark = sv_mortalcopy(*mark);
60779a30 3453 }
3455055f
FC
3454 }
3455 }
3a76ca88 3456 /* We assume first XSUB in &DB::sub is the called one. */
f5719c02 3457 if (UNLIKELY(PL_curcopdb)) {
3a76ca88
RGS
3458 SAVEVPTR(PL_curcop);
3459 PL_curcop = PL_curcopdb;
3460 PL_curcopdb = NULL;
3461 }
3462 /* Do we need to open block here? XXXX */
72df79cf 3463
3464 /* CvXSUB(cv) must not be NULL because newXS() refuses NULL xsub address */
3465 assert(CvXSUB(cv));
16c91539 3466 CvXSUB(cv)(aTHX_ cv);
3a76ca88
RGS
3467
3468 /* Enforce some sanity in scalar context. */
89a18b40
DM
3469 if (gimme == G_SCALAR) {
3470 SV **svp = PL_stack_base + markix + 1;
3471 if (svp != PL_stack_sp) {
3472 *svp = svp > PL_stack_sp ? &PL_sv_undef : *PL_stack_sp;
3473 PL_stack_sp = svp;
3474 }
3a76ca88 3475 }
a57c6685 3476 LEAVE;
f1025168
NC
3477 return NORMAL;
3478 }
a0d0e21e
LW
3479}
3480
44a8e56a 3481void
864dbfa3 3482Perl_sub_crush_depth(pTHX_ CV *cv)
44a8e56a 3483{
7918f24d
NC
3484 PERL_ARGS_ASSERT_SUB_CRUSH_DEPTH;
3485
44a8e56a 3486 if (CvANON(cv))
9014280d 3487 Perl_warner(aTHX_ packWARN(WARN_RECURSION), "Deep recursion on anonymous subroutine");
44a8e56a 3488 else {
35c1215d 3489 Perl_warner(aTHX_ packWARN(WARN_RECURSION), "Deep recursion on subroutine \"%"SVf"\"",
ecf05a58 3490 SVfARG(cv_name(cv,NULL,0)));
44a8e56a
PP
3491 }
3492}
3493
a0d0e21e
LW
3494PP(pp_aelem)
3495{
20b7effb 3496 dSP;
a0d0e21e 3497 SV** svp;
a3b680e6 3498 SV* const elemsv = POPs;
d804643f 3499 IV elem = SvIV(elemsv);
502c6561 3500 AV *const av = MUTABLE_AV(POPs);
e1ec3a88 3501 const U32 lval = PL_op->op_flags & OPf_MOD || LVRET;
bbfdc870 3502 const U32 defer = PL_op->op_private & OPpLVAL_DEFER;
4ad10a0b
VP
3503 const bool localizing = PL_op->op_private & OPpLVAL_INTRO;
3504 bool preeminent = TRUE;
be6c24e0 3505 SV *sv;
a0d0e21e 3506
5d9574c1 3507 if (UNLIKELY(SvROK(elemsv) && !SvGAMAGIC(elemsv) && ckWARN(WARN_MISC)))
95b63a38
JH
3508 Perl_warner(aTHX_ packWARN(WARN_MISC),
3509 "Use of reference \"%"SVf"\" as array index",
be2597df 3510 SVfARG(elemsv));
5d9574c1 3511 if (UNLIKELY(SvTYPE(av) != SVt_PVAV))
a0d0e21e 3512 RETPUSHUNDEF;
4ad10a0b 3513
5d9574c1 3514 if (UNLIKELY(localizing)) {
4ad10a0b
VP
3515 MAGIC *mg;
3516 HV *stash;
3517
3518 /* If we can determine whether the element exist,
3519 * Try to preserve the existenceness of a tied array
3520 * element by using EXISTS and DELETE if possible.
3521 * Fallback to FETCH and STORE otherwise. */
3522 if (SvCANEXISTDELETE(av))
3523 preeminent = av_exists(av, elem);
3524 }
3525
68dc0745 3526 svp = av_fetch(av, elem, lval && !defer);
a0d0e21e 3527 if (lval) {
2b573ace 3528#ifdef PERL_MALLOC_WRAP