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[perl5.git] / op.c
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4b88f280 1#line 2 "op.c"
a0d0e21e 2/* op.c
79072805 3 *
1129b882
NC
4 * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
5 * 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 by Larry Wall and others
79072805
LW
6 *
7 * You may distribute under the terms of either the GNU General Public
8 * License or the Artistic License, as specified in the README file.
9 *
a0d0e21e
LW
10 */
11
12/*
4ac71550
TC
13 * 'You see: Mr. Drogo, he married poor Miss Primula Brandybuck. She was
14 * our Mr. Bilbo's first cousin on the mother's side (her mother being the
15 * youngest of the Old Took's daughters); and Mr. Drogo was his second
16 * cousin. So Mr. Frodo is his first *and* second cousin, once removed
17 * either way, as the saying is, if you follow me.' --the Gaffer
18 *
19 * [p.23 of _The Lord of the Rings_, I/i: "A Long-Expected Party"]
79072805
LW
20 */
21
166f8a29
DM
22/* This file contains the functions that create, manipulate and optimize
23 * the OP structures that hold a compiled perl program.
24 *
25 * A Perl program is compiled into a tree of OPs. Each op contains
26 * structural pointers (eg to its siblings and the next op in the
27 * execution sequence), a pointer to the function that would execute the
28 * op, plus any data specific to that op. For example, an OP_CONST op
29 * points to the pp_const() function and to an SV containing the constant
30 * value. When pp_const() is executed, its job is to push that SV onto the
31 * stack.
32 *
33 * OPs are mainly created by the newFOO() functions, which are mainly
34 * called from the parser (in perly.y) as the code is parsed. For example
35 * the Perl code $a + $b * $c would cause the equivalent of the following
36 * to be called (oversimplifying a bit):
37 *
38 * newBINOP(OP_ADD, flags,
39 * newSVREF($a),
40 * newBINOP(OP_MULTIPLY, flags, newSVREF($b), newSVREF($c))
41 * )
42 *
43 * Note that during the build of miniperl, a temporary copy of this file
44 * is made, called opmini.c.
45 */
ccfc67b7 46
61b743bb
DM
47/*
48Perl's compiler is essentially a 3-pass compiler with interleaved phases:
49
50 A bottom-up pass
51 A top-down pass
52 An execution-order pass
53
54The bottom-up pass is represented by all the "newOP" routines and
55the ck_ routines. The bottom-upness is actually driven by yacc.
56So at the point that a ck_ routine fires, we have no idea what the
57context is, either upward in the syntax tree, or either forward or
58backward in the execution order. (The bottom-up parser builds that
59part of the execution order it knows about, but if you follow the "next"
60links around, you'll find it's actually a closed loop through the
ef9da979 61top level node.)
61b743bb
DM
62
63Whenever the bottom-up parser gets to a node that supplies context to
64its components, it invokes that portion of the top-down pass that applies
65to that part of the subtree (and marks the top node as processed, so
66if a node further up supplies context, it doesn't have to take the
67plunge again). As a particular subcase of this, as the new node is
68built, it takes all the closed execution loops of its subcomponents
69and links them into a new closed loop for the higher level node. But
70it's still not the real execution order.
71
72The actual execution order is not known till we get a grammar reduction
73to a top-level unit like a subroutine or file that will be called by
74"name" rather than via a "next" pointer. At that point, we can call
75into peep() to do that code's portion of the 3rd pass. It has to be
76recursive, but it's recursive on basic blocks, not on tree nodes.
77*/
78
06e0342d 79/* To implement user lexical pragmas, there needs to be a way at run time to
b3ca2e83
NC
80 get the compile time state of %^H for that block. Storing %^H in every
81 block (or even COP) would be very expensive, so a different approach is
82 taken. The (running) state of %^H is serialised into a tree of HE-like
83 structs. Stores into %^H are chained onto the current leaf as a struct
84 refcounted_he * with the key and the value. Deletes from %^H are saved
85 with a value of PL_sv_placeholder. The state of %^H at any point can be
86 turned back into a regular HV by walking back up the tree from that point's
06e0342d 87 leaf, ignoring any key you've already seen (placeholder or not), storing
b3ca2e83
NC
88 the rest into the HV structure, then removing the placeholders. Hence
89 memory is only used to store the %^H deltas from the enclosing COP, rather
90 than the entire %^H on each COP.
91
92 To cause actions on %^H to write out the serialisation records, it has
93 magic type 'H'. This magic (itself) does nothing, but its presence causes
94 the values to gain magic type 'h', which has entries for set and clear.
c28fe1ec 95 C<Perl_magic_sethint> updates C<PL_compiling.cop_hints_hash> with a store
34795b44 96 record, with deletes written by C<Perl_magic_clearhint>. C<SAVEHINTS>
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97 saves the current C<PL_compiling.cop_hints_hash> on the save stack, so that
98 it will be correctly restored when any inner compiling scope is exited.
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99*/
100
79072805 101#include "EXTERN.h"
864dbfa3 102#define PERL_IN_OP_C
79072805 103#include "perl.h"
77ca0c92 104#include "keywords.h"
2846acbf 105#include "feature.h"
74529a43 106#include "regcomp.h"
79072805 107
16c91539 108#define CALL_PEEP(o) PL_peepp(aTHX_ o)
1a0a2ba9 109#define CALL_RPEEP(o) PL_rpeepp(aTHX_ o)
16c91539 110#define CALL_OPFREEHOOK(o) if (PL_opfreehook) PL_opfreehook(aTHX_ o)
a2efc822 111
8be227ab
FC
112/* See the explanatory comments above struct opslab in op.h. */
113
7aef8e5b 114#ifdef PERL_DEBUG_READONLY_OPS
3107b51f
FC
115# define PERL_SLAB_SIZE 128
116# define PERL_MAX_SLAB_SIZE 4096
117# include <sys/mman.h>
7aef8e5b 118#endif
3107b51f 119
7aef8e5b 120#ifndef PERL_SLAB_SIZE
8be227ab 121# define PERL_SLAB_SIZE 64
7aef8e5b
FC
122#endif
123#ifndef PERL_MAX_SLAB_SIZE
e6cee8c0 124# define PERL_MAX_SLAB_SIZE 2048
7aef8e5b 125#endif
8be227ab
FC
126
127/* rounds up to nearest pointer */
7aef8e5b
FC
128#define SIZE_TO_PSIZE(x) (((x) + sizeof(I32 *) - 1)/sizeof(I32 *))
129#define DIFF(o,p) ((size_t)((I32 **)(p) - (I32**)(o)))
8be227ab
FC
130
131static OPSLAB *
132S_new_slab(pTHX_ size_t sz)
133{
7aef8e5b 134#ifdef PERL_DEBUG_READONLY_OPS
3107b51f
FC
135 OPSLAB *slab = (OPSLAB *) mmap(0, sz * sizeof(I32 *),
136 PROT_READ|PROT_WRITE,
137 MAP_ANON|MAP_PRIVATE, -1, 0);
138 DEBUG_m(PerlIO_printf(Perl_debug_log, "mapped %lu at %p\n",
139 (unsigned long) sz, slab));
140 if (slab == MAP_FAILED) {
141 perror("mmap failed");
142 abort();
143 }
144 slab->opslab_size = (U16)sz;
7aef8e5b 145#else
8be227ab 146 OPSLAB *slab = (OPSLAB *)PerlMemShared_calloc(sz, sizeof(I32 *));
7aef8e5b 147#endif
8be227ab
FC
148 slab->opslab_first = (OPSLOT *)((I32 **)slab + sz - 1);
149 return slab;
150}
151
e7372881
FC
152/* requires double parens and aTHX_ */
153#define DEBUG_S_warn(args) \
154 DEBUG_S( \
155 PerlIO_printf(Perl_debug_log, "%s", SvPVx_nolen(Perl_mess args)) \
156 )
157
8be227ab
FC
158void *
159Perl_Slab_Alloc(pTHX_ size_t sz)
160{
161 dVAR;
162 OPSLAB *slab;
163 OPSLAB *slab2;
164 OPSLOT *slot;
165 OP *o;
5cb52f30 166 size_t opsz, space;
8be227ab 167
2073970f
NC
168 /* We only allocate ops from the slab during subroutine compilation.
169 We find the slab via PL_compcv, hence that must be non-NULL. It could
170 also be pointing to a subroutine which is now fully set up (CvROOT()
171 pointing to the top of the optree for that sub), or a subroutine
172 which isn't using the slab allocator. If our sanity checks aren't met,
173 don't use a slab, but allocate the OP directly from the heap. */
8be227ab
FC
174 if (!PL_compcv || CvROOT(PL_compcv)
175 || (CvSTART(PL_compcv) && !CvSLABBED(PL_compcv)))
176 return PerlMemShared_calloc(1, sz);
177
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NC
178 /* While the subroutine is under construction, the slabs are accessed via
179 CvSTART(), to avoid needing to expand PVCV by one pointer for something
180 unneeded at runtime. Once a subroutine is constructed, the slabs are
181 accessed via CvROOT(). So if CvSTART() is NULL, no slab has been
182 allocated yet. See the commit message for 8be227ab5eaa23f2 for more
183 details. */
184 if (!CvSTART(PL_compcv)) {
8be227ab
FC
185 CvSTART(PL_compcv) =
186 (OP *)(slab = S_new_slab(aTHX_ PERL_SLAB_SIZE));
187 CvSLABBED_on(PL_compcv);
188 slab->opslab_refcnt = 2; /* one for the CV; one for the new OP */
189 }
190 else ++(slab = (OPSLAB *)CvSTART(PL_compcv))->opslab_refcnt;
191
5cb52f30
FC
192 opsz = SIZE_TO_PSIZE(sz);
193 sz = opsz + OPSLOT_HEADER_P;
8be227ab 194
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NC
195 /* The slabs maintain a free list of OPs. In particular, constant folding
196 will free up OPs, so it makes sense to re-use them where possible. A
197 freed up slot is used in preference to a new allocation. */
8be227ab
FC
198 if (slab->opslab_freed) {
199 OP **too = &slab->opslab_freed;
200 o = *too;
e7372881 201 DEBUG_S_warn((aTHX_ "found free op at %p, slab %p", o, slab));
8be227ab 202 while (o && DIFF(OpSLOT(o), OpSLOT(o)->opslot_next) < sz) {
e7372881 203 DEBUG_S_warn((aTHX_ "Alas! too small"));
8be227ab 204 o = *(too = &o->op_next);
94b67eb2 205 if (o) { DEBUG_S_warn((aTHX_ "found another free op at %p", o)); }
8be227ab
FC
206 }
207 if (o) {
208 *too = o->op_next;
5cb52f30 209 Zero(o, opsz, I32 *);
8be227ab
FC
210 o->op_slabbed = 1;
211 return (void *)o;
212 }
213 }
214
7aef8e5b 215#define INIT_OPSLOT \
8be227ab
FC
216 slot->opslot_slab = slab; \
217 slot->opslot_next = slab2->opslab_first; \
218 slab2->opslab_first = slot; \
219 o = &slot->opslot_op; \
220 o->op_slabbed = 1
221
222 /* The partially-filled slab is next in the chain. */
223 slab2 = slab->opslab_next ? slab->opslab_next : slab;
224 if ((space = DIFF(&slab2->opslab_slots, slab2->opslab_first)) < sz) {
225 /* Remaining space is too small. */
226
8be227ab
FC
227 /* If we can fit a BASEOP, add it to the free chain, so as not
228 to waste it. */
229 if (space >= SIZE_TO_PSIZE(sizeof(OP)) + OPSLOT_HEADER_P) {
230 slot = &slab2->opslab_slots;
231 INIT_OPSLOT;
232 o->op_type = OP_FREED;
233 o->op_next = slab->opslab_freed;
234 slab->opslab_freed = o;
235 }
236
237 /* Create a new slab. Make this one twice as big. */
238 slot = slab2->opslab_first;
239 while (slot->opslot_next) slot = slot->opslot_next;
af7751f6
FC
240 slab2 = S_new_slab(aTHX_
241 (DIFF(slab2, slot)+1)*2 > PERL_MAX_SLAB_SIZE
e6cee8c0 242 ? PERL_MAX_SLAB_SIZE
af7751f6 243 : (DIFF(slab2, slot)+1)*2);
9963ffa2
FC
244 slab2->opslab_next = slab->opslab_next;
245 slab->opslab_next = slab2;
8be227ab
FC
246 }
247 assert(DIFF(&slab2->opslab_slots, slab2->opslab_first) >= sz);
248
249 /* Create a new op slot */
250 slot = (OPSLOT *)((I32 **)slab2->opslab_first - sz);
251 assert(slot >= &slab2->opslab_slots);
51c777ca
FC
252 if (DIFF(&slab2->opslab_slots, slot)
253 < SIZE_TO_PSIZE(sizeof(OP)) + OPSLOT_HEADER_P)
254 slot = &slab2->opslab_slots;
8be227ab 255 INIT_OPSLOT;
e7372881 256 DEBUG_S_warn((aTHX_ "allocating op at %p, slab %p", o, slab));
8be227ab
FC
257 return (void *)o;
258}
259
7aef8e5b 260#undef INIT_OPSLOT
8be227ab 261
7aef8e5b 262#ifdef PERL_DEBUG_READONLY_OPS
3107b51f
FC
263void
264Perl_Slab_to_ro(pTHX_ OPSLAB *slab)
265{
266 PERL_ARGS_ASSERT_SLAB_TO_RO;
267
268 if (slab->opslab_readonly) return;
269 slab->opslab_readonly = 1;
270 for (; slab; slab = slab->opslab_next) {
271 /*DEBUG_U(PerlIO_printf(Perl_debug_log,"mprotect ->ro %lu at %p\n",
272 (unsigned long) slab->opslab_size, slab));*/
273 if (mprotect(slab, slab->opslab_size * sizeof(I32 *), PROT_READ))
274 Perl_warn(aTHX_ "mprotect for %p %lu failed with %d", slab,
275 (unsigned long)slab->opslab_size, errno);
276 }
277}
278
7bbbc3c0
NC
279void
280Perl_Slab_to_rw(pTHX_ OPSLAB *const slab)
3107b51f 281{
3107b51f
FC
282 OPSLAB *slab2;
283
284 PERL_ARGS_ASSERT_SLAB_TO_RW;
285
3107b51f
FC
286 if (!slab->opslab_readonly) return;
287 slab2 = slab;
288 for (; slab2; slab2 = slab2->opslab_next) {
289 /*DEBUG_U(PerlIO_printf(Perl_debug_log,"mprotect ->rw %lu at %p\n",
290 (unsigned long) size, slab2));*/
291 if (mprotect((void *)slab2, slab2->opslab_size * sizeof(I32 *),
292 PROT_READ|PROT_WRITE)) {
293 Perl_warn(aTHX_ "mprotect RW for %p %lu failed with %d", slab,
294 (unsigned long)slab2->opslab_size, errno);
295 }
296 }
297 slab->opslab_readonly = 0;
298}
299
300#else
9e4d7a13 301# define Slab_to_rw(op) NOOP
3107b51f
FC
302#endif
303
8be227ab
FC
304/* This cannot possibly be right, but it was copied from the old slab
305 allocator, to which it was originally added, without explanation, in
306 commit 083fcd5. */
7aef8e5b 307#ifdef NETWARE
8be227ab 308# define PerlMemShared PerlMem
7aef8e5b 309#endif
8be227ab
FC
310
311void
312Perl_Slab_Free(pTHX_ void *op)
313{
20429ba0 314 dVAR;
8be227ab
FC
315 OP * const o = (OP *)op;
316 OPSLAB *slab;
317
318 PERL_ARGS_ASSERT_SLAB_FREE;
319
320 if (!o->op_slabbed) {
90840c5d
RU
321 if (!o->op_static)
322 PerlMemShared_free(op);
8be227ab
FC
323 return;
324 }
325
326 slab = OpSLAB(o);
327 /* If this op is already freed, our refcount will get screwy. */
328 assert(o->op_type != OP_FREED);
329 o->op_type = OP_FREED;
330 o->op_next = slab->opslab_freed;
331 slab->opslab_freed = o;
e7372881 332 DEBUG_S_warn((aTHX_ "free op at %p, recorded in slab %p", o, slab));
8be227ab
FC
333 OpslabREFCNT_dec_padok(slab);
334}
335
336void
337Perl_opslab_free_nopad(pTHX_ OPSLAB *slab)
338{
339 dVAR;
340 const bool havepad = !!PL_comppad;
341 PERL_ARGS_ASSERT_OPSLAB_FREE_NOPAD;
342 if (havepad) {
343 ENTER;
344 PAD_SAVE_SETNULLPAD();
345 }
346 opslab_free(slab);
347 if (havepad) LEAVE;
348}
349
350void
351Perl_opslab_free(pTHX_ OPSLAB *slab)
352{
20429ba0 353 dVAR;
8be227ab
FC
354 OPSLAB *slab2;
355 PERL_ARGS_ASSERT_OPSLAB_FREE;
e7372881 356 DEBUG_S_warn((aTHX_ "freeing slab %p", slab));
8be227ab
FC
357 assert(slab->opslab_refcnt == 1);
358 for (; slab; slab = slab2) {
359 slab2 = slab->opslab_next;
7aef8e5b 360#ifdef DEBUGGING
8be227ab 361 slab->opslab_refcnt = ~(size_t)0;
7aef8e5b
FC
362#endif
363#ifdef PERL_DEBUG_READONLY_OPS
3107b51f
FC
364 DEBUG_m(PerlIO_printf(Perl_debug_log, "Deallocate slab at %p\n",
365 slab));
366 if (munmap(slab, slab->opslab_size * sizeof(I32 *))) {
367 perror("munmap failed");
368 abort();
369 }
7aef8e5b 370#else
8be227ab 371 PerlMemShared_free(slab);
7aef8e5b 372#endif
8be227ab
FC
373 }
374}
375
376void
377Perl_opslab_force_free(pTHX_ OPSLAB *slab)
378{
379 OPSLAB *slab2;
380 OPSLOT *slot;
7aef8e5b 381#ifdef DEBUGGING
8be227ab 382 size_t savestack_count = 0;
7aef8e5b 383#endif
8be227ab
FC
384 PERL_ARGS_ASSERT_OPSLAB_FORCE_FREE;
385 slab2 = slab;
386 do {
387 for (slot = slab2->opslab_first;
388 slot->opslot_next;
389 slot = slot->opslot_next) {
390 if (slot->opslot_op.op_type != OP_FREED
391 && !(slot->opslot_op.op_savefree
7aef8e5b 392#ifdef DEBUGGING
8be227ab 393 && ++savestack_count
7aef8e5b 394#endif
8be227ab
FC
395 )
396 ) {
397 assert(slot->opslot_op.op_slabbed);
8be227ab 398 op_free(&slot->opslot_op);
3bf28c7e 399 if (slab->opslab_refcnt == 1) goto free;
8be227ab
FC
400 }
401 }
402 } while ((slab2 = slab2->opslab_next));
403 /* > 1 because the CV still holds a reference count. */
404 if (slab->opslab_refcnt > 1) { /* still referenced by the savestack */
7aef8e5b 405#ifdef DEBUGGING
8be227ab 406 assert(savestack_count == slab->opslab_refcnt-1);
7aef8e5b 407#endif
ee5ee853
FC
408 /* Remove the CV’s reference count. */
409 slab->opslab_refcnt--;
8be227ab
FC
410 return;
411 }
412 free:
413 opslab_free(slab);
414}
415
3107b51f
FC
416#ifdef PERL_DEBUG_READONLY_OPS
417OP *
418Perl_op_refcnt_inc(pTHX_ OP *o)
419{
420 if(o) {
372eab01
NC
421 OPSLAB *const slab = o->op_slabbed ? OpSLAB(o) : NULL;
422 if (slab && slab->opslab_readonly) {
83519873 423 Slab_to_rw(slab);
372eab01
NC
424 ++o->op_targ;
425 Slab_to_ro(slab);
426 } else {
427 ++o->op_targ;
428 }
3107b51f
FC
429 }
430 return o;
431
432}
433
434PADOFFSET
435Perl_op_refcnt_dec(pTHX_ OP *o)
436{
372eab01
NC
437 PADOFFSET result;
438 OPSLAB *const slab = o->op_slabbed ? OpSLAB(o) : NULL;
439
3107b51f 440 PERL_ARGS_ASSERT_OP_REFCNT_DEC;
372eab01
NC
441
442 if (slab && slab->opslab_readonly) {
83519873 443 Slab_to_rw(slab);
372eab01
NC
444 result = --o->op_targ;
445 Slab_to_ro(slab);
446 } else {
447 result = --o->op_targ;
448 }
449 return result;
3107b51f
FC
450}
451#endif
e50aee73 452/*
ce6f1cbc 453 * In the following definition, the ", (OP*)0" is just to make the compiler
a5f75d66 454 * think the expression is of the right type: croak actually does a Siglongjmp.
e50aee73 455 */
11343788 456#define CHECKOP(type,o) \
ce6f1cbc 457 ((PL_op_mask && PL_op_mask[type]) \
5dc0d613 458 ? ( op_free((OP*)o), \
cb77fdf0 459 Perl_croak(aTHX_ "'%s' trapped by operation mask", PL_op_desc[type]), \
ce6f1cbc 460 (OP*)0 ) \
16c91539 461 : PL_check[type](aTHX_ (OP*)o))
e50aee73 462
e6438c1a 463#define RETURN_UNLIMITED_NUMBER (PERL_INT_MAX / 2)
c53d7c7d 464
cba5a3b0
DG
465#define CHANGE_TYPE(o,type) \
466 STMT_START { \
467 o->op_type = (OPCODE)type; \
468 o->op_ppaddr = PL_ppaddr[type]; \
469 } STMT_END
470
ce16c625 471STATIC SV*
cea2e8a9 472S_gv_ename(pTHX_ GV *gv)
4633a7c4 473{
46c461b5 474 SV* const tmpsv = sv_newmortal();
7918f24d
NC
475
476 PERL_ARGS_ASSERT_GV_ENAME;
477
bd61b366 478 gv_efullname3(tmpsv, gv, NULL);
ce16c625 479 return tmpsv;
4633a7c4
LW
480}
481
76e3520e 482STATIC OP *
cea2e8a9 483S_no_fh_allowed(pTHX_ OP *o)
79072805 484{
7918f24d
NC
485 PERL_ARGS_ASSERT_NO_FH_ALLOWED;
486
cea2e8a9 487 yyerror(Perl_form(aTHX_ "Missing comma after first argument to %s function",
53e06cf0 488 OP_DESC(o)));
11343788 489 return o;
79072805
LW
490}
491
76e3520e 492STATIC OP *
ce16c625 493S_too_few_arguments_sv(pTHX_ OP *o, SV *namesv, U32 flags)
79072805 494{
ce16c625
BF
495 PERL_ARGS_ASSERT_TOO_FEW_ARGUMENTS_SV;
496 yyerror_pv(Perl_form(aTHX_ "Not enough arguments for %"SVf, namesv),
497 SvUTF8(namesv) | flags);
498 return o;
499}
500
501STATIC OP *
502S_too_few_arguments_pv(pTHX_ OP *o, const char* name, U32 flags)
503{
504 PERL_ARGS_ASSERT_TOO_FEW_ARGUMENTS_PV;
505 yyerror_pv(Perl_form(aTHX_ "Not enough arguments for %s", name), flags);
506 return o;
507}
508
509STATIC OP *
510S_too_many_arguments_pv(pTHX_ OP *o, const char *name, U32 flags)
511{
512 PERL_ARGS_ASSERT_TOO_MANY_ARGUMENTS_PV;
7918f24d 513
ce16c625 514 yyerror_pv(Perl_form(aTHX_ "Too many arguments for %s", name), flags);
11343788 515 return o;
79072805
LW
516}
517
76e3520e 518STATIC OP *
ce16c625 519S_too_many_arguments_sv(pTHX_ OP *o, SV *namesv, U32 flags)
79072805 520{
ce16c625 521 PERL_ARGS_ASSERT_TOO_MANY_ARGUMENTS_SV;
7918f24d 522
ce16c625
BF
523 yyerror_pv(Perl_form(aTHX_ "Too many arguments for %"SVf, SVfARG(namesv)),
524 SvUTF8(namesv) | flags);
11343788 525 return o;
79072805
LW
526}
527
76e3520e 528STATIC void
ce16c625 529S_bad_type_pv(pTHX_ I32 n, const char *t, const char *name, U32 flags, const OP *kid)
8990e307 530{
ce16c625
BF
531 PERL_ARGS_ASSERT_BAD_TYPE_PV;
532
533 yyerror_pv(Perl_form(aTHX_ "Type of arg %d to %s must be %s (not %s)",
534 (int)n, name, t, OP_DESC(kid)), flags);
535}
7918f24d 536
ce16c625 537STATIC void
7b3b0904 538S_bad_type_gv(pTHX_ I32 n, const char *t, GV *gv, U32 flags, const OP *kid)
ce16c625 539{
7b3b0904
FC
540 SV * const namesv = gv_ename(gv);
541 PERL_ARGS_ASSERT_BAD_TYPE_GV;
ce16c625
BF
542
543 yyerror_pv(Perl_form(aTHX_ "Type of arg %d to %"SVf" must be %s (not %s)",
544 (int)n, SVfARG(namesv), t, OP_DESC(kid)), SvUTF8(namesv) | flags);
8990e307
LW
545}
546
7a52d87a 547STATIC void
eb796c7f 548S_no_bareword_allowed(pTHX_ OP *o)
7a52d87a 549{
7918f24d
NC
550 PERL_ARGS_ASSERT_NO_BAREWORD_ALLOWED;
551
eb8433b7
NC
552 if (PL_madskills)
553 return; /* various ok barewords are hidden in extra OP_NULL */
5a844595 554 qerror(Perl_mess(aTHX_
35c1215d 555 "Bareword \"%"SVf"\" not allowed while \"strict subs\" in use",
be2597df 556 SVfARG(cSVOPo_sv)));
eb796c7f 557 o->op_private &= ~OPpCONST_STRICT; /* prevent warning twice about the same OP */
7a52d87a
GS
558}
559
79072805
LW
560/* "register" allocation */
561
562PADOFFSET
d6447115 563Perl_allocmy(pTHX_ const char *const name, const STRLEN len, const U32 flags)
93a17b20 564{
97aff369 565 dVAR;
a0d0e21e 566 PADOFFSET off;
12bd6ede 567 const bool is_our = (PL_parser->in_my == KEY_our);
a0d0e21e 568
7918f24d
NC
569 PERL_ARGS_ASSERT_ALLOCMY;
570
48d0d1be 571 if (flags & ~SVf_UTF8)
d6447115
NC
572 Perl_croak(aTHX_ "panic: allocmy illegal flag bits 0x%" UVxf,
573 (UV)flags);
574
575 /* Until we're using the length for real, cross check that we're being
576 told the truth. */
577 assert(strlen(name) == len);
578
59f00321 579 /* complain about "my $<special_var>" etc etc */
d6447115 580 if (len &&
3edf23ff 581 !(is_our ||
155aba94 582 isALPHA(name[1]) ||
b14845b4 583 ((flags & SVf_UTF8) && isIDFIRST_utf8((U8 *)name+1)) ||
d6447115 584 (name[1] == '_' && (*name == '$' || len > 2))))
834a4ddd 585 {
6b58708b 586 /* name[2] is true if strlen(name) > 2 */
b14845b4
FC
587 if (!(flags & SVf_UTF8 && UTF8_IS_START(name[1]))
588 && (!isPRINT(name[1]) || strchr("\t\n\r\f", name[1]))) {
d6447115
NC
589 yyerror(Perl_form(aTHX_ "Can't use global %c^%c%.*s in \"%s\"",
590 name[0], toCTRL(name[1]), (int)(len - 2), name + 2,
aab6a793 591 PL_parser->in_my == KEY_state ? "state" : "my"));
d1544d85 592 } else {
ce16c625
BF
593 yyerror_pv(Perl_form(aTHX_ "Can't use global %.*s in \"%s\"", (int) len, name,
594 PL_parser->in_my == KEY_state ? "state" : "my"), flags & SVf_UTF8);
46fc3d4c 595 }
a0d0e21e 596 }
4055dbce
RS
597 else if (len == 2 && name[1] == '_' && !is_our)
598 /* diag_listed_as: Use of my $_ is experimental */
599 Perl_ck_warner_d(aTHX_ packWARN(WARN_EXPERIMENTAL__LEXICAL_TOPIC),
600 "Use of %s $_ is experimental",
601 PL_parser->in_my == KEY_state
602 ? "state"
603 : "my");
748a9306 604
dd2155a4 605 /* allocate a spare slot and store the name in that slot */
93a17b20 606
cc76b5cc 607 off = pad_add_name_pvn(name, len,
48d0d1be
BF
608 (is_our ? padadd_OUR :
609 PL_parser->in_my == KEY_state ? padadd_STATE : 0)
610 | ( flags & SVf_UTF8 ? SVf_UTF8 : 0 ),
12bd6ede 611 PL_parser->in_my_stash,
3edf23ff 612 (is_our
133706a6
RGS
613 /* $_ is always in main::, even with our */
614 ? (PL_curstash && !strEQ(name,"$_") ? PL_curstash : PL_defstash)
5c284bb0 615 : NULL
cca43f78 616 )
dd2155a4 617 );
a74073ad
DM
618 /* anon sub prototypes contains state vars should always be cloned,
619 * otherwise the state var would be shared between anon subs */
620
621 if (PL_parser->in_my == KEY_state && CvANON(PL_compcv))
622 CvCLONE_on(PL_compcv);
623
dd2155a4 624 return off;
79072805
LW
625}
626
c0b8aebd
FC
627/*
628=for apidoc alloccopstash
629
630Available only under threaded builds, this function allocates an entry in
631C<PL_stashpad> for the stash passed to it.
632
633=cut
634*/
635
d4d03940
FC
636#ifdef USE_ITHREADS
637PADOFFSET
1dc74fdb 638Perl_alloccopstash(pTHX_ HV *hv)
d4d03940
FC
639{
640 PADOFFSET off = 0, o = 1;
641 bool found_slot = FALSE;
642
1dc74fdb
FC
643 PERL_ARGS_ASSERT_ALLOCCOPSTASH;
644
645 if (PL_stashpad[PL_stashpadix] == hv) return PL_stashpadix;
d4d03940 646
1dc74fdb
FC
647 for (; o < PL_stashpadmax; ++o) {
648 if (PL_stashpad[o] == hv) return PL_stashpadix = o;
649 if (!PL_stashpad[o] || SvTYPE(PL_stashpad[o]) != SVt_PVHV)
d4d03940
FC
650 found_slot = TRUE, off = o;
651 }
652 if (!found_slot) {
1dc74fdb
FC
653 Renew(PL_stashpad, PL_stashpadmax + 10, HV *);
654 Zero(PL_stashpad + PL_stashpadmax, 10, HV *);
655 off = PL_stashpadmax;
656 PL_stashpadmax += 10;
d4d03940
FC
657 }
658
1dc74fdb 659 PL_stashpad[PL_stashpadix = off] = hv;
d4d03940
FC
660 return off;
661}
662#endif
663
d2c837a0
DM
664/* free the body of an op without examining its contents.
665 * Always use this rather than FreeOp directly */
666
4136a0f7 667static void
d2c837a0
DM
668S_op_destroy(pTHX_ OP *o)
669{
d2c837a0
DM
670 FreeOp(o);
671}
672
79072805
LW
673/* Destructor */
674
675void
864dbfa3 676Perl_op_free(pTHX_ OP *o)
79072805 677{
27da23d5 678 dVAR;
acb36ea4 679 OPCODE type;
79072805 680
8be227ab
FC
681 /* Though ops may be freed twice, freeing the op after its slab is a
682 big no-no. */
683 assert(!o || !o->op_slabbed || OpSLAB(o)->opslab_refcnt != ~(size_t)0);
8be227ab
FC
684 /* During the forced freeing of ops after compilation failure, kidops
685 may be freed before their parents. */
686 if (!o || o->op_type == OP_FREED)
79072805
LW
687 return;
688
67566ccd 689 type = o->op_type;
7934575e 690 if (o->op_private & OPpREFCOUNTED) {
67566ccd 691 switch (type) {
7934575e
GS
692 case OP_LEAVESUB:
693 case OP_LEAVESUBLV:
694 case OP_LEAVEEVAL:
695 case OP_LEAVE:
696 case OP_SCOPE:
697 case OP_LEAVEWRITE:
67566ccd
AL
698 {
699 PADOFFSET refcnt;
7934575e 700 OP_REFCNT_LOCK;
4026c95a 701 refcnt = OpREFCNT_dec(o);
7934575e 702 OP_REFCNT_UNLOCK;
bfd0ff22
NC
703 if (refcnt) {
704 /* Need to find and remove any pattern match ops from the list
705 we maintain for reset(). */
706 find_and_forget_pmops(o);
4026c95a 707 return;
67566ccd 708 }
bfd0ff22 709 }
7934575e
GS
710 break;
711 default:
712 break;
713 }
714 }
715
f37b8c3f
VP
716 /* Call the op_free hook if it has been set. Do it now so that it's called
717 * at the right time for refcounted ops, but still before all of the kids
718 * are freed. */
719 CALL_OPFREEHOOK(o);
720
11343788 721 if (o->op_flags & OPf_KIDS) {
eb578fdb 722 OP *kid, *nextkid;
11343788 723 for (kid = cUNOPo->op_first; kid; kid = nextkid) {
85e6fe83 724 nextkid = kid->op_sibling; /* Get before next freeing kid */
79072805 725 op_free(kid);
85e6fe83 726 }
79072805 727 }
513f78f7
FC
728 if (type == OP_NULL)
729 type = (OPCODE)o->op_targ;
acb36ea4 730
9e4d7a13
NC
731 if (o->op_slabbed)
732 Slab_to_rw(OpSLAB(o));
fc97af9c 733
acb36ea4
GS
734 /* COP* is not cleared by op_clear() so that we may track line
735 * numbers etc even after null() */
513f78f7 736 if (type == OP_NEXTSTATE || type == OP_DBSTATE) {
acb36ea4 737 cop_free((COP*)o);
3235b7a3 738 }
acb36ea4
GS
739
740 op_clear(o);
238a4c30 741 FreeOp(o);
4d494880
DM
742#ifdef DEBUG_LEAKING_SCALARS
743 if (PL_op == o)
5f66b61c 744 PL_op = NULL;
4d494880 745#endif
acb36ea4 746}
79072805 747
93c66552
DM
748void
749Perl_op_clear(pTHX_ OP *o)
acb36ea4 750{
13137afc 751
27da23d5 752 dVAR;
7918f24d
NC
753
754 PERL_ARGS_ASSERT_OP_CLEAR;
755
eb8433b7 756#ifdef PERL_MAD
df31c78c
NC
757 mad_free(o->op_madprop);
758 o->op_madprop = 0;
eb8433b7
NC
759#endif
760
761 retry:
11343788 762 switch (o->op_type) {
acb36ea4 763 case OP_NULL: /* Was holding old type, if any. */
eb8433b7 764 if (PL_madskills && o->op_targ != OP_NULL) {
61a59f30 765 o->op_type = (Optype)o->op_targ;
eb8433b7
NC
766 o->op_targ = 0;
767 goto retry;
768 }
4d193d44 769 case OP_ENTERTRY:
acb36ea4 770 case OP_ENTEREVAL: /* Was holding hints. */
acb36ea4 771 o->op_targ = 0;
a0d0e21e 772 break;
a6006777 773 default:
ac4c12e7 774 if (!(o->op_flags & OPf_REF)
ef69c8fc 775 || (PL_check[o->op_type] != Perl_ck_ftst))
a6006777
PP
776 break;
777 /* FALL THROUGH */
463ee0b2 778 case OP_GVSV:
79072805 779 case OP_GV:
a6006777 780 case OP_AELEMFAST:
93bad3fd 781 {
f7461760
Z
782 GV *gv = (o->op_type == OP_GV || o->op_type == OP_GVSV)
783#ifdef USE_ITHREADS
784 && PL_curpad
785#endif
786 ? cGVOPo_gv : NULL;
b327b36f
NC
787 /* It's possible during global destruction that the GV is freed
788 before the optree. Whilst the SvREFCNT_inc is happy to bump from
789 0 to 1 on a freed SV, the corresponding SvREFCNT_dec from 1 to 0
790 will trigger an assertion failure, because the entry to sv_clear
791 checks that the scalar is not already freed. A check of for
792 !SvIS_FREED(gv) turns out to be invalid, because during global
793 destruction the reference count can be forced down to zero
794 (with SVf_BREAK set). In which case raising to 1 and then
795 dropping to 0 triggers cleanup before it should happen. I
796 *think* that this might actually be a general, systematic,
797 weakness of the whole idea of SVf_BREAK, in that code *is*
798 allowed to raise and lower references during global destruction,
799 so any *valid* code that happens to do this during global
800 destruction might well trigger premature cleanup. */
801 bool still_valid = gv && SvREFCNT(gv);
802
803 if (still_valid)
804 SvREFCNT_inc_simple_void(gv);
350de78d 805#ifdef USE_ITHREADS
6a077020
DM
806 if (cPADOPo->op_padix > 0) {
807 /* No GvIN_PAD_off(cGVOPo_gv) here, because other references
808 * may still exist on the pad */
809 pad_swipe(cPADOPo->op_padix, TRUE);
810 cPADOPo->op_padix = 0;
811 }
350de78d 812#else
6a077020 813 SvREFCNT_dec(cSVOPo->op_sv);
a0714e2c 814 cSVOPo->op_sv = NULL;
350de78d 815#endif
b327b36f 816 if (still_valid) {
f7461760 817 int try_downgrade = SvREFCNT(gv) == 2;
fc2b2dca 818 SvREFCNT_dec_NN(gv);
f7461760
Z
819 if (try_downgrade)
820 gv_try_downgrade(gv);
821 }
6a077020 822 }
79072805 823 break;
a1ae71d2 824 case OP_METHOD_NAMED:
79072805 825 case OP_CONST:
996c9baa 826 case OP_HINTSEVAL:
11343788 827 SvREFCNT_dec(cSVOPo->op_sv);
a0714e2c 828 cSVOPo->op_sv = NULL;
3b1c21fa
AB
829#ifdef USE_ITHREADS
830 /** Bug #15654
831 Even if op_clear does a pad_free for the target of the op,
6a077020 832 pad_free doesn't actually remove the sv that exists in the pad;
3b1c21fa
AB
833 instead it lives on. This results in that it could be reused as
834 a target later on when the pad was reallocated.
835 **/
836 if(o->op_targ) {
837 pad_swipe(o->op_targ,1);
838 o->op_targ = 0;
839 }
840#endif
79072805 841 break;
c9df4fda 842 case OP_DUMP:
748a9306
LW
843 case OP_GOTO:
844 case OP_NEXT:
845 case OP_LAST:
846 case OP_REDO:
11343788 847 if (o->op_flags & (OPf_SPECIAL|OPf_STACKED|OPf_KIDS))
748a9306
LW
848 break;
849 /* FALL THROUGH */
a0d0e21e 850 case OP_TRANS:
bb16bae8 851 case OP_TRANSR:
acb36ea4 852 if (o->op_private & (OPpTRANS_FROM_UTF|OPpTRANS_TO_UTF)) {
99a1d0d1 853 assert(o->op_type == OP_TRANS || o->op_type == OP_TRANSR);
043e41b8
DM
854#ifdef USE_ITHREADS
855 if (cPADOPo->op_padix > 0) {
856 pad_swipe(cPADOPo->op_padix, TRUE);
857 cPADOPo->op_padix = 0;
858 }
859#else
a0ed51b3 860 SvREFCNT_dec(cSVOPo->op_sv);
a0714e2c 861 cSVOPo->op_sv = NULL;
043e41b8 862#endif
acb36ea4
GS
863 }
864 else {
ea71c68d 865 PerlMemShared_free(cPVOPo->op_pv);
bd61b366 866 cPVOPo->op_pv = NULL;
acb36ea4 867 }
a0d0e21e
LW
868 break;
869 case OP_SUBST:
20e98b0f 870 op_free(cPMOPo->op_pmreplrootu.op_pmreplroot);
971a9dd3 871 goto clear_pmop;
748a9306 872 case OP_PUSHRE:
971a9dd3 873#ifdef USE_ITHREADS
20e98b0f 874 if (cPMOPo->op_pmreplrootu.op_pmtargetoff) {
dd2155a4
DM
875 /* No GvIN_PAD_off here, because other references may still
876 * exist on the pad */
20e98b0f 877 pad_swipe(cPMOPo->op_pmreplrootu.op_pmtargetoff, TRUE);
971a9dd3
GS
878 }
879#else
ad64d0ec 880 SvREFCNT_dec(MUTABLE_SV(cPMOPo->op_pmreplrootu.op_pmtargetgv));
971a9dd3
GS
881#endif
882 /* FALL THROUGH */
a0d0e21e 883 case OP_MATCH:
8782bef2 884 case OP_QR:
971a9dd3 885clear_pmop:
867940b8
DM
886 if (!(cPMOPo->op_pmflags & PMf_CODELIST_PRIVATE))
887 op_free(cPMOPo->op_code_list);
68e2671b 888 cPMOPo->op_code_list = NULL;
23083432 889 forget_pmop(cPMOPo);
20e98b0f 890 cPMOPo->op_pmreplrootu.op_pmreplroot = NULL;
9cddf794
NC
891 /* we use the same protection as the "SAFE" version of the PM_ macros
892 * here since sv_clean_all might release some PMOPs
5f8cb046
DM
893 * after PL_regex_padav has been cleared
894 * and the clearing of PL_regex_padav needs to
895 * happen before sv_clean_all
896 */
13137afc
AB
897#ifdef USE_ITHREADS
898 if(PL_regex_pad) { /* We could be in destruction */
402d2eb1 899 const IV offset = (cPMOPo)->op_pmoffset;
9cddf794 900 ReREFCNT_dec(PM_GETRE(cPMOPo));
402d2eb1
NC
901 PL_regex_pad[offset] = &PL_sv_undef;
902 sv_catpvn_nomg(PL_regex_pad[0], (const char *)&offset,
903 sizeof(offset));
13137afc 904 }
9cddf794
NC
905#else
906 ReREFCNT_dec(PM_GETRE(cPMOPo));
907 PM_SETRE(cPMOPo, NULL);
1eb1540c 908#endif
13137afc 909
a0d0e21e 910 break;
79072805
LW
911 }
912
743e66e6 913 if (o->op_targ > 0) {
11343788 914 pad_free(o->op_targ);
743e66e6
GS
915 o->op_targ = 0;
916 }
79072805
LW
917}
918
76e3520e 919STATIC void
3eb57f73
HS
920S_cop_free(pTHX_ COP* cop)
921{
7918f24d
NC
922 PERL_ARGS_ASSERT_COP_FREE;
923
05ec9bb3 924 CopFILE_free(cop);
0453d815 925 if (! specialWARN(cop->cop_warnings))
72dc9ed5 926 PerlMemShared_free(cop->cop_warnings);
20439bc7 927 cophh_free(CopHINTHASH_get(cop));
515abc43
FC
928 if (PL_curcop == cop)
929 PL_curcop = NULL;
3eb57f73
HS
930}
931
c2b1997a 932STATIC void
c4bd3ae5 933S_forget_pmop(pTHX_ PMOP *const o
c4bd3ae5 934 )
c2b1997a
NC
935{
936 HV * const pmstash = PmopSTASH(o);
7918f24d
NC
937
938 PERL_ARGS_ASSERT_FORGET_PMOP;
939
e39a6381 940 if (pmstash && !SvIS_FREED(pmstash) && SvMAGICAL(pmstash)) {
ad64d0ec 941 MAGIC * const mg = mg_find((const SV *)pmstash, PERL_MAGIC_symtab);
c2b1997a
NC
942 if (mg) {
943 PMOP **const array = (PMOP**) mg->mg_ptr;
944 U32 count = mg->mg_len / sizeof(PMOP**);
945 U32 i = count;
946
947 while (i--) {
948 if (array[i] == o) {
949 /* Found it. Move the entry at the end to overwrite it. */
950 array[i] = array[--count];
951 mg->mg_len = count * sizeof(PMOP**);
952 /* Could realloc smaller at this point always, but probably
953 not worth it. Probably worth free()ing if we're the
954 last. */
955 if(!count) {
956 Safefree(mg->mg_ptr);
957 mg->mg_ptr = NULL;
958 }
959 break;
960 }
961 }
962 }
963 }
1cdf7faf
NC
964 if (PL_curpm == o)
965 PL_curpm = NULL;
c2b1997a
NC
966}
967
bfd0ff22
NC
968STATIC void
969S_find_and_forget_pmops(pTHX_ OP *o)
970{
7918f24d
NC
971 PERL_ARGS_ASSERT_FIND_AND_FORGET_PMOPS;
972
bfd0ff22
NC
973 if (o->op_flags & OPf_KIDS) {
974 OP *kid = cUNOPo->op_first;
975 while (kid) {
976 switch (kid->op_type) {
977 case OP_SUBST:
978 case OP_PUSHRE:
979 case OP_MATCH:
980 case OP_QR:
23083432 981 forget_pmop((PMOP*)kid);
bfd0ff22
NC
982 }
983 find_and_forget_pmops(kid);
984 kid = kid->op_sibling;
985 }
986 }
987}
988
93c66552
DM
989void
990Perl_op_null(pTHX_ OP *o)
8990e307 991{
27da23d5 992 dVAR;
7918f24d
NC
993
994 PERL_ARGS_ASSERT_OP_NULL;
995
acb36ea4
GS
996 if (o->op_type == OP_NULL)
997 return;
eb8433b7
NC
998 if (!PL_madskills)
999 op_clear(o);
11343788
MB
1000 o->op_targ = o->op_type;
1001 o->op_type = OP_NULL;
22c35a8c 1002 o->op_ppaddr = PL_ppaddr[OP_NULL];
8990e307
LW
1003}
1004
4026c95a
SH
1005void
1006Perl_op_refcnt_lock(pTHX)
1007{
27da23d5 1008 dVAR;
96a5add6 1009 PERL_UNUSED_CONTEXT;
4026c95a
SH
1010 OP_REFCNT_LOCK;
1011}
1012
1013void
1014Perl_op_refcnt_unlock(pTHX)
1015{
27da23d5 1016 dVAR;
96a5add6 1017 PERL_UNUSED_CONTEXT;
4026c95a
SH
1018 OP_REFCNT_UNLOCK;
1019}
1020
79072805
LW
1021/* Contextualizers */
1022
d9088386
Z
1023/*
1024=for apidoc Am|OP *|op_contextualize|OP *o|I32 context
1025
1026Applies a syntactic context to an op tree representing an expression.
1027I<o> is the op tree, and I<context> must be C<G_SCALAR>, C<G_ARRAY>,
1028or C<G_VOID> to specify the context to apply. The modified op tree
1029is returned.
1030
1031=cut
1032*/
1033
1034OP *
1035Perl_op_contextualize(pTHX_ OP *o, I32 context)
1036{
1037 PERL_ARGS_ASSERT_OP_CONTEXTUALIZE;
1038 switch (context) {
1039 case G_SCALAR: return scalar(o);
1040 case G_ARRAY: return list(o);
1041 case G_VOID: return scalarvoid(o);
1042 default:
5637ef5b
NC
1043 Perl_croak(aTHX_ "panic: op_contextualize bad context %ld",
1044 (long) context);
d9088386
Z
1045 return o;
1046 }
1047}
1048
5983a79d
BM
1049/*
1050=head1 Optree Manipulation Functions
79072805 1051
5983a79d
BM
1052=for apidoc Am|OP*|op_linklist|OP *o
1053This function is the implementation of the L</LINKLIST> macro. It should
1054not be called directly.
1055
1056=cut
1057*/
1058
1059OP *
1060Perl_op_linklist(pTHX_ OP *o)
79072805 1061{
3edf23ff 1062 OP *first;
79072805 1063
5983a79d 1064 PERL_ARGS_ASSERT_OP_LINKLIST;
7918f24d 1065
11343788
MB
1066 if (o->op_next)
1067 return o->op_next;
79072805
LW
1068
1069 /* establish postfix order */
3edf23ff
AL
1070 first = cUNOPo->op_first;
1071 if (first) {
eb578fdb 1072 OP *kid;
3edf23ff
AL
1073 o->op_next = LINKLIST(first);
1074 kid = first;
1075 for (;;) {
1076 if (kid->op_sibling) {
79072805 1077 kid->op_next = LINKLIST(kid->op_sibling);
3edf23ff
AL
1078 kid = kid->op_sibling;
1079 } else {
11343788 1080 kid->op_next = o;
3edf23ff
AL
1081 break;
1082 }
79072805
LW
1083 }
1084 }
1085 else
11343788 1086 o->op_next = o;
79072805 1087
11343788 1088 return o->op_next;
79072805
LW
1089}
1090
1f676739 1091static OP *
2dd5337b 1092S_scalarkids(pTHX_ OP *o)
79072805 1093{
11343788 1094 if (o && o->op_flags & OPf_KIDS) {
bfed75c6 1095 OP *kid;
11343788 1096 for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling)
79072805
LW
1097 scalar(kid);
1098 }
11343788 1099 return o;
79072805
LW
1100}
1101
76e3520e 1102STATIC OP *
cea2e8a9 1103S_scalarboolean(pTHX_ OP *o)
8990e307 1104{
97aff369 1105 dVAR;
7918f24d
NC
1106
1107 PERL_ARGS_ASSERT_SCALARBOOLEAN;
1108
6b7c6d95
FC
1109 if (o->op_type == OP_SASSIGN && cBINOPo->op_first->op_type == OP_CONST
1110 && !(cBINOPo->op_first->op_flags & OPf_SPECIAL)) {
d008e5eb 1111 if (ckWARN(WARN_SYNTAX)) {
6867be6d 1112 const line_t oldline = CopLINE(PL_curcop);
a0d0e21e 1113
2b7cddde
NC
1114 if (PL_parser && PL_parser->copline != NOLINE) {
1115 /* This ensures that warnings are reported at the first line
1116 of the conditional, not the last. */
53a7735b 1117 CopLINE_set(PL_curcop, PL_parser->copline);
2b7cddde 1118 }
9014280d 1119 Perl_warner(aTHX_ packWARN(WARN_SYNTAX), "Found = in conditional, should be ==");
57843af0 1120 CopLINE_set(PL_curcop, oldline);
d008e5eb 1121 }
a0d0e21e 1122 }
11343788 1123 return scalar(o);
8990e307
LW
1124}
1125
0920b7fa
FC
1126static SV *
1127S_op_varname(pTHX_ const OP *o)
1128{
1129 assert(o);
1130 assert(o->op_type == OP_PADAV || o->op_type == OP_RV2AV ||
1131 o->op_type == OP_PADHV || o->op_type == OP_RV2HV);
1132 {
1133 const char funny = o->op_type == OP_PADAV
1134 || o->op_type == OP_RV2AV ? '@' : '%';
1135 if (o->op_type == OP_RV2AV || o->op_type == OP_RV2HV) {
1136 GV *gv;
1137 if (cUNOPo->op_first->op_type != OP_GV
1138 || !(gv = cGVOPx_gv(cUNOPo->op_first)))
1139 return NULL;
1140 return varname(gv, funny, 0, NULL, 0, 1);
1141 }
1142 return
1143 varname(MUTABLE_GV(PL_compcv), funny, o->op_targ, NULL, 0, 1);
1144 }
1145}
1146
429a2555
FC
1147static void
1148S_scalar_slice_warning(pTHX_ const OP *o)
1149{
1150 OP *kid;
1151 const char lbrack =
1152 o->op_type == OP_KVHSLICE || o->op_type == OP_HSLICE ? '{' : '[';
1153 const char rbrack =
1154 o->op_type == OP_KVHSLICE || o->op_type == OP_HSLICE ? '}' : ']';
1155 const char funny =
1156 o->op_type == OP_ASLICE || o->op_type == OP_HSLICE ? '@' : '%';
1157 SV *name;
1158 SV *keysv;
1159 const char *key = NULL;
1160
1161 if (!(o->op_private & OPpSLICEWARNING))
1162 return;
1163 if (PL_parser && PL_parser->error_count)
1164 /* This warning can be nonsensical when there is a syntax error. */
1165 return;
1166
1167 kid = cLISTOPo->op_first;
1168 kid = kid->op_sibling; /* get past pushmark */
1169 /* weed out false positives: any ops that can return lists */
1170 switch (kid->op_type) {
1171 case OP_BACKTICK:
1172 case OP_GLOB:
1173 case OP_READLINE:
1174 case OP_MATCH:
1175 case OP_RV2AV:
1176 case OP_EACH:
1177 case OP_VALUES:
1178 case OP_KEYS:
1179 case OP_SPLIT:
1180 case OP_LIST:
1181 case OP_SORT:
1182 case OP_REVERSE:
1183 case OP_ENTERSUB:
1184 case OP_CALLER:
1185 case OP_LSTAT:
1186 case OP_STAT:
1187 case OP_READDIR:
1188 case OP_SYSTEM:
1189 case OP_TMS:
1190 case OP_LOCALTIME:
1191 case OP_GMTIME:
1192 case OP_ENTEREVAL:
1193 case OP_REACH:
1194 case OP_RKEYS:
1195 case OP_RVALUES:
1196 return;
1197 }
1198 assert(kid->op_sibling);
1199 name = S_op_varname(aTHX_ kid->op_sibling);
1200 if (!name) /* XS module fiddling with the op tree */
1201 return;
1202 if (kid->op_type == OP_CONST) {
1203 keysv = kSVOP_sv;
1204 if (SvPOK(kSVOP_sv)) {
1205 SV *sv = keysv;
1206 keysv = sv_newmortal();
1207 pv_pretty(keysv, SvPVX_const(sv), SvCUR(sv), 32, NULL, NULL,
1208 PERL_PV_PRETTY_DUMP |PERL_PV_ESCAPE_UNI_DETECT);
1209 }
1210 else if (!SvOK(keysv))
1211 key = "undef";
1212 }
1213 else key = "...";
1214 assert(SvPOK(name));
1215 sv_chop(name,SvPVX(name)+1);
1216 if (key)
1217 /* diag_listed_as: Scalar value %%s[%s] better written as $%s[%s] */
1218 Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
1219 "Scalar value %c%"SVf"%c%s%c better written as $%"SVf
1220 "%c%s%c",
1221 funny, SVfARG(name), lbrack, key, rbrack, SVfARG(name),
1222 lbrack, key, rbrack);
1223 else
1224 /* diag_listed_as: Scalar value %%s[%s] better written as $%s[%s] */
1225 Perl_warner(aTHX_ packWARN(WARN_SYNTAX),
1226 "Scalar value %c%"SVf"%c%"SVf"%c better written as $%"
1227 SVf"%c%"SVf"%c",
1228 funny, SVfARG(name), lbrack, keysv, rbrack,
1229 SVfARG(name), lbrack, keysv, rbrack);
1230}
1231
8990e307 1232OP *
864dbfa3 1233Perl_scalar(pTHX_ OP *o)
79072805 1234{
27da23d5 1235 dVAR;
79072805
LW
1236 OP *kid;
1237
a0d0e21e 1238 /* assumes no premature commitment */
13765c85
DM
1239 if (!o || (PL_parser && PL_parser->error_count)
1240 || (o->op_flags & OPf_WANT)
5dc0d613 1241 || o->op_type == OP_RETURN)
7e363e51 1242 {
11343788 1243 return o;
7e363e51 1244 }
79072805 1245
5dc0d613 1246 o->op_flags = (o->op_flags & ~OPf_WANT) | OPf_WANT_SCALAR;
79072805 1247
11343788 1248 switch (o->op_type) {
79072805 1249 case OP_REPEAT:
11343788 1250 scalar(cBINOPo->op_first);
8990e307 1251 break;
79072805
LW
1252 case OP_OR:
1253 case OP_AND:
1254 case OP_COND_EXPR:
11343788 1255 for (kid = cUNOPo->op_first->op_sibling; kid; kid = kid->op_sibling)
8990e307 1256 scalar(kid);
79072805 1257 break;
a0d0e21e 1258 /* FALL THROUGH */
a6d8037e 1259 case OP_SPLIT:
79072805 1260 case OP_MATCH:
8782bef2 1261 case OP_QR:
79072805
LW
1262 case OP_SUBST:
1263 case OP_NULL:
8990e307 1264 default:
11343788
MB
1265 if (o->op_flags & OPf_KIDS) {
1266 for (kid = cUNOPo->op_first; kid; kid = kid->op_sibling)
8990e307
LW
1267 scalar(kid);
1268 }
79072805
LW
1269 break;
1270 case OP_LEAVE:
1271 case OP_LEAVETRY:
5dc0d613 1272 kid = cLISTOPo->op_first;
54310121 1273 scalar(kid);
25b991bf
VP
1274 kid = kid->op_sibling;
1275 do_kids:
1276 while (kid) {
1277 OP *sib = kid->op_sibling;
c08f093b
VP
1278 if (sib && kid->op_type != OP_LEAVEWHEN)
1279 scalarvoid(kid);
1280 else
54310121 1281 scalar(kid);
25b991bf 1282 kid = sib;
54310121 1283 }
11206fdd 1284 PL_curcop = &PL_compiling;
54310121 1285 break;
748a9306 1286 case OP_SCOPE:
79072805 1287 case OP_LINESEQ:
8990e307 1288 case OP_LIST:
25b991bf
VP
1289 kid = cLISTOPo->op_first;
1290 goto do_kids;
a801c63c 1291 case OP_SORT:
a2a5de95 1292 Perl_ck_warner(aTHX_ packWARN(WARN_VOID), "Useless use of sort in scalar context");
553e7bb0 1293 break;
95a31aad
FC
1294 case OP_KVHSLICE:
1295 case OP_KVASLICE:
429a2555 1296 S_scalar_slice_warning(aTHX_ o);
79072805 1297 }
11343788 1298 return o;
79072805
LW
1299}
1300
1301OP *
864dbfa3 1302Perl_scalarvoid(pTHX_ OP *o)
79072805 1303{
27da23d5 1304 dVAR;
79072805 1305 OP *kid;
095b19d1 1306 SV *useless_sv = NULL;
c445ea15 1307 const char* useless = NULL;
8990e307 1308 SV* sv;
2ebea0a1
GS
1309 U8 want;
1310
7918f24d
NC
1311 PERL_ARGS_ASSERT_SCALARVOID;
1312
eb8433b7
NC
1313 /* trailing mad null ops don't count as "there" for void processing */
1314 if (PL_madskills &&
1315 o->op_type != OP_NULL &&
1316 o->op_sibling &&
1317 o->op_sibling->op_type == OP_NULL)
1318 {
1319 OP *sib;
1320 for (sib = o->op_sibling;
1321 sib && sib->op_type == OP_NULL;
1322 sib = sib->op_sibling) ;
1323
1324 if (!sib)
1325 return o;
1326 }
1327
acb36ea4 1328 if (o->op_type == OP_NEXTSTATE
acb36ea4
GS
1329 || o->op_type == OP_DBSTATE
1330 || (o->op_type == OP_NULL && (o->op_targ == OP_NEXTSTATE
acb36ea4 1331 || o->op_targ == OP_DBSTATE)))
2ebea0a1 1332 PL_curcop = (COP*)o; /* for warning below */
79072805 1333
54310121 1334 /* assumes no premature commitment */
2ebea0a1 1335 want = o->op_flags & OPf_WANT;
13765c85
DM
1336 if ((want && want != OPf_WANT_SCALAR)
1337 || (PL_parser && PL_parser->error_count)
25b991bf 1338 || o->op_type == OP_RETURN || o->op_type == OP_REQUIRE || o->op_type == OP_LEAVEWHEN)
7e363e51 1339 {
11343788 1340 return o;
7e363e51 1341 }
79072805 1342
b162f9ea 1343 if ((o->op_private & OPpTARGET_MY)
7e363e51
GS
1344 && (PL_opargs[o->op_type] & OA_TARGLEX))/* OPp share the meaning */
1345 {
b162f9ea 1346 return scalar(o); /* As if inside SASSIGN */
7e363e51 1347 }
1c846c1f 1348
5dc0d613 1349 o->op_flags = (o->op_flags & ~OPf_WANT) | OPf_WANT_VOID;
79072805 1350
11343788 1351 switch (o->op_type) {
79072805 1352 default:
22c35a8c 1353 if (!(PL_opargs[o->op_type] & OA_FOLDCONST))
8990e307 1354 break;
36477c24
PP
1355 /* FALL THROUGH */
1356 case OP_REPEAT:
11343788 1357 if (o->op_flags & OPf_STACKED)
8990e307 1358 break;
5d82c453
GA
1359 goto func_ops;
1360 case OP_SUBSTR:
1361 if (o->op_private == 4)
1362 break;
8990e307
LW
1363 /* FALL THROUGH */
1364 case OP_GVSV:
1365 case OP_WANTARRAY:
1366 case OP_GV:
74295f0b 1367 case OP_SMARTMATCH:
8990e307
LW
1368 case OP_PADSV:
1369 case OP_PADAV:
1370 case OP_PADHV:
1371 case OP_PADANY:
1372 case OP_AV2ARYLEN:
8990e307 1373 case OP_REF:
a0d0e21e
LW
1374 case OP_REFGEN:
1375 case OP_SREFGEN:
8990e307
LW
1376 case OP_DEFINED:
1377 case OP_HEX:
1378 case OP_OCT:
1379 case OP_LENGTH:
8990e307
LW
1380 case OP_VEC:
1381 case OP_INDEX:
1382 case OP_RINDEX:
1383 case OP_SPRINTF:
1384 case OP_AELEM:
1385 case OP_AELEMFAST:
93bad3fd 1386 case OP_AELEMFAST_LEX:
8990e307 1387 case OP_ASLICE:
6dd3e0f2 1388 case OP_KVASLICE:
8990e307
LW
1389 case OP_HELEM:
1390 case OP_HSLICE:
5cae3edb 1391 case OP_KVHSLICE:
8990e307
LW
1392 case OP_UNPACK:
1393 case OP_PACK:
8990e307
LW
1394 case OP_JOIN:
1395 case OP_LSLICE:
1396 case OP_ANONLIST:
1397 case OP_ANONHASH:
1398 case OP_SORT:
1399 case OP_REVERSE:
1400 case OP_RANGE:
1401 case OP_FLIP:
1402 case OP_FLOP:
1403 case OP_CALLER:
1404 case OP_FILENO:
1405 case OP_EOF:
1406 case OP_TELL:
1407 case OP_GETSOCKNAME:
1408 case OP_GETPEERNAME:
1409 case OP_READLINK:
1410 case OP_TELLDIR:
1411 case OP_GETPPID:
1412 case OP_GETPGRP:
1413 case OP_GETPRIORITY:
1414 case OP_TIME:
1415 case OP_TMS:
1416 case OP_LOCALTIME:
1417 case OP_GMTIME:
1418 case OP_GHBYNAME:
1419 case OP_GHBYADDR:
1420 case OP_GHOSTENT:
1421 case OP_GNBYNAME:
1422 case OP_GNBYADDR:
1423 case OP_GNETENT:
1424 case OP_GPBYNAME:
1425 case OP_GPBYNUMBER:
1426 case OP_GPROTOENT:
1427 case OP_GSBYNAME:
1428 case OP_GSBYPORT:
1429 case OP_GSERVENT:
1430 case OP_GPWNAM:
1431 case OP_GPWUID:
1432 case OP_GGRNAM:
1433 case OP_GGRGID:
1434 case OP_GETLOGIN:
78e1b766 1435 case OP_PROTOTYPE:
703227f5 1436 case OP_RUNCV:
5d82c453 1437 func_ops:
64aac5a9 1438 if (!(o->op_private & (OPpLVAL_INTRO|OPpOUR_INTRO)))
74295f0b 1439 /* Otherwise it's "Useless use of grep iterator" */
f5df4782 1440 useless = OP_DESC(o);
75068674
RGS
1441 break;
1442
1443 case OP_SPLIT:
1444 kid = cLISTOPo->op_first;
1445 if (kid && kid->op_type == OP_PUSHRE
1446#ifdef USE_ITHREADS
1447 && !((PMOP*)kid)->op_pmreplrootu.op_pmtargetoff)
1448#else
1449 && !((PMOP*)kid)->op_pmreplrootu.op_pmtargetgv)
1450#endif
1451 useless = OP_DESC(o);
8990e307
LW
1452 break;
1453
9f82cd5f
YST
1454 case OP_NOT:
1455 kid = cUNOPo->op_first;
1456 if (kid->op_type != OP_MATCH && kid->op_type != OP_SUBST &&
bb16bae8 1457 kid->op_type != OP_TRANS && kid->op_type != OP_TRANSR) {
9f82cd5f
YST
1458 goto func_ops;
1459 }
1460 useless = "negative pattern binding (!~)";
1461 break;
1462
4f4d7508
DC
1463 case OP_SUBST:
1464 if (cPMOPo->op_pmflags & PMf_NONDESTRUCT)
8db9069c 1465 useless = "non-destructive substitution (s///r)";
4f4d7508
DC
1466 break;
1467
bb16bae8
FC
1468 case OP_TRANSR:
1469 useless = "non-destructive transliteration (tr///r)";
1470 break;
1471
8990e307
LW
1472 case OP_RV2GV:
1473 case OP_RV2SV:
1474 case OP_RV2AV:
1475 case OP_RV2HV:
192587c2 1476 if (!(o->op_private & (OPpLVAL_INTRO|OPpOUR_INTRO)) &&
11343788 1477 (!o->op_sibling || o->op_sibling->op_type != OP_READLINE))
8990e307
LW
1478 useless = "a variable";
1479 break;
79072805
LW
1480
1481 case OP_CONST:
7766f137 1482 sv = cSVOPo_sv;
7a52d87a
GS
1483 if (cSVOPo->op_private & OPpCONST_STRICT)
1484 no_bareword_allowed(o);
1485 else {
d008e5eb 1486 if (ckWARN(WARN_VOID)) {
e7fec78e 1487 /* don't warn on optimised away booleans, eg
b5a930ec 1488 * use constant Foo, 5; Foo || print; */
e7fec78e 1489 if (cSVOPo->op_private & OPpCONST_SHORTCIRCUIT)
d4c19fe8 1490 useless = NULL;
960b4253
MG
1491 /* the constants 0 and 1 are permitted as they are
1492 conventionally used as dummies in constructs like
1493 1 while some_condition_with_side_effects; */
e7fec78e 1494 else if (SvNIOK(sv) && (SvNV(sv) == 0.0 || SvNV(sv) == 1.0))
d4c19fe8 1495 useless = NULL;
d008e5eb 1496 else if (SvPOK(sv)) {
1e3f3188
KW
1497 SV * const dsv = newSVpvs("");
1498 useless_sv
1499 = Perl_newSVpvf(aTHX_
1500 "a constant (%s)",
1501 pv_pretty(dsv, SvPVX_const(sv),
1502 SvCUR(sv), 32, NULL, NULL,
1503 PERL_PV_PRETTY_DUMP
1504 | PERL_PV_ESCAPE_NOCLEAR
1505 | PERL_PV_ESCAPE_UNI_DETECT));
1506 SvREFCNT_dec_NN(dsv);
d008e5eb 1507 }
919f76a3 1508 else if (SvOK(sv)) {
095b19d1 1509 useless_sv = Perl_newSVpvf(aTHX_ "a constant (%"SVf")", sv);
919f76a3
RGS
1510 }
1511 else
1512 useless = "a constant (undef)";
8990e307
LW
1513 }
1514 }
93c66552 1515 op_null(o); /* don't execute or even remember it */
79072805
LW
1516 break;
1517
1518 case OP_POSTINC:
11343788 1519 o->op_type = OP_PREINC; /* pre-increment is faster */
22c35a8c 1520 o->op_ppaddr = PL_ppaddr[OP_PREINC];
79072805
LW
1521 break;
1522
1523 case OP_POSTDEC:
11343788 1524 o->op_type = OP_PREDEC; /* pre-decrement is faster */
22c35a8c 1525 o->op_ppaddr = PL_ppaddr[OP_PREDEC];
79072805
LW
1526 break;
1527
679d6c4e
HS
1528 case OP_I_POSTINC:
1529 o->op_type = OP_I_PREINC; /* pre-increment is faster */
1530 o->op_ppaddr = PL_ppaddr[OP_I_PREINC];
1531 break;
1532
1533 case OP_I_POSTDEC:
1534 o->op_type = OP_I_PREDEC; /* pre-decrement is faster */
1535 o->op_ppaddr = PL_ppaddr[OP_I_PREDEC];
1536 break;
1537
f2f8fd84
GG
1538 case OP_SASSIGN: {
1539 OP *rv2gv;
1540 UNOP *refgen, *rv2cv;
1541 LISTOP *exlist;
1542
1543 if ((o->op_private & ~OPpASSIGN_BACKWARDS) != 2)
1544 break;
1545
1546 rv2gv = ((BINOP *)o)->op_last;
1547 if (!rv2gv || rv2gv->op_type != OP_RV2GV)
1548 break;
1549
1550 refgen = (UNOP *)((BINOP *)o)->op_first;
1551
1552 if (!refgen || refgen->op_type != OP_REFGEN)
1553 break;
1554
1555 exlist = (LISTOP *)refgen->op_first;
1556 if (!exlist || exlist->op_type != OP_NULL
1557 || exlist->op_targ != OP_LIST)
1558 break;
1559
1560 if (exlist->op_first->op_type != OP_PUSHMARK)
1561 break;
1562
1563 rv2cv = (UNOP*)exlist->op_last;
1564
1565 if (rv2cv->op_type != OP_RV2CV)
1566 break;
1567
1568 assert ((rv2gv->op_private & OPpDONT_INIT_GV) == 0);
1569 assert ((o->op_private & OPpASSIGN_CV_TO_GV) == 0);
1570 assert ((rv2cv->op_private & OPpMAY_RETURN_CONSTANT) == 0);
1571
1572 o->op_private |= OPpASSIGN_CV_TO_GV;
1573 rv2gv->op_private |= OPpDONT_INIT_GV;
1574 rv2cv->op_private |= OPpMAY_RETURN_CONSTANT;
1575
1576 break;
1577 }
1578
540dd770
GG
1579 case OP_AASSIGN: {
1580 inplace_aassign(o);
1581 break;
1582 }
1583
79072805
LW
1584 case OP_OR:
1585 case OP_AND:
edbe35ea
VP
1586 kid = cLOGOPo->op_first;
1587 if (kid->op_type == OP_NOT
1588 && (kid->op_flags & OPf_KIDS)
1589 && !PL_madskills) {
1590 if (o->op_type == OP_AND) {
1591 o->op_type = OP_OR;
1592 o->op_ppaddr = PL_ppaddr[OP_OR];
1593 } else {
1594 o->op_type = OP_AND;
1595 o->op_ppaddr = PL_ppaddr[OP_AND];
1596 }
1597 op_null(kid);
1598 }
1599
c963b151 1600 case OP_DOR:
79072805 1601 case OP_COND_EXPR:
0d863452
RH
1602 case OP_ENTERGIVEN:
1603 case OP_ENTERWHEN:
11343788 1604 for (kid = cUNOPo->op_first->op_sibling; kid; kid = kid->op_sibling)
79072805
LW
1605 scalarvoid(kid);
1606 break;
5aabfad6 1607
a0d0e21e 1608 case OP_NULL:
11343788 1609 if (o->op_flags & OPf_STACKED)
a0d0e21e 1610 break;
5aabfad6 1611 /* FALL THROUGH */
2ebea0a1
GS
1612 case OP_NEXTSTATE:
1613 case OP_DBSTATE:
79072805
LW
1614 case OP_ENTERTRY:
1615 case OP_ENTER:
11343788 1616 if (!(o->op_flags & OPf_KIDS))
79072805 1617 break;
54310121 1618 /* FALL THROUGH */
463ee0b2 1619 case OP_SCOPE:
79072805
LW
1620 case OP_LEAVE:
1621 case OP_LEAVETRY:
a0d0e21e 1622 case OP_LEAVELOOP:
79072805 1623 case OP_LINESEQ:
79072805 1624 case OP_LIST:
0d863452
RH
1625 case OP_LEAVEGIVEN:
1626 case OP_LEAVEWHEN:
11343788 1627 for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling)
79072805
LW
1628 scalarvoid(kid);
1629 break;
c90c0ff4 1630 case OP_ENTEREVAL:
5196be3e 1631 scalarkids(o);
c90c0ff4 1632 break;
d6483035 1633 case OP_SCALAR:
5196be3e 1634 return scalar(o);
79072805 1635 }
095b19d1
NC
1636
1637 if (useless_sv) {
1638 /* mortalise it, in case warnings are fatal. */
1639 Perl_ck_warner(aTHX_ packWARN(WARN_VOID),
1640 "Useless use of %"SVf" in void context",
1641 sv_2mortal(useless_sv));
1642 }
1643 else if (useless) {
1644 Perl_ck_warner(aTHX_ packWARN(WARN_VOID),
1645 "Useless use of %s in void context",
1646 useless);
1647 }
11343788 1648 return o;
79072805
LW
1649}
1650
1f676739 1651static OP *
412da003 1652S_listkids(pTHX_ OP *o)
79072805 1653{
11343788 1654 if (o && o->op_flags & OPf_KIDS) {
6867be6d 1655 OP *kid;
11343788 1656 for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling)
79072805
LW
1657 list(kid);
1658 }
11343788 1659 return o;
79072805
LW
1660}
1661
1662OP *
864dbfa3 1663Perl_list(pTHX_ OP *o)
79072805 1664{
27da23d5 1665 dVAR;
79072805
LW
1666 OP *kid;
1667
a0d0e21e 1668 /* assumes no premature commitment */
13765c85
DM
1669 if (!o || (o->op_flags & OPf_WANT)
1670 || (PL_parser && PL_parser->error_count)
5dc0d613 1671 || o->op_type == OP_RETURN)
7e363e51 1672 {
11343788 1673 return o;
7e363e51 1674 }
79072805 1675
b162f9ea 1676 if ((o->op_private & OPpTARGET_MY)
7e363e51
GS
1677 && (PL_opargs[o->op_type] & OA_TARGLEX))/* OPp share the meaning */
1678 {
b162f9ea 1679 return o; /* As if inside SASSIGN */
7e363e51 1680 }
1c846c1f 1681
5dc0d613 1682 o->op_flags = (o->op_flags & ~OPf_WANT) | OPf_WANT_LIST;
79072805 1683
11343788 1684 switch (o->op_type) {
79072805
LW
1685 case OP_FLOP:
1686 case OP_REPEAT:
11343788 1687 list(cBINOPo->op_first);
79072805
LW
1688 break;
1689 case OP_OR:
1690 case OP_AND:
1691 case OP_COND_EXPR:
11343788 1692 for (kid = cUNOPo->op_first->op_sibling; kid; kid = kid->op_sibling)
79072805
LW
1693 list(kid);
1694 break;
1695 default:
1696 case OP_MATCH:
8782bef2 1697 case OP_QR:
79072805
LW
1698 case OP_SUBST:
1699 case OP_NULL:
11343788 1700 if (!(o->op_flags & OPf_KIDS))
79072805 1701 break;
11343788
MB
1702 if (!o->op_next && cUNOPo->op_first->op_type == OP_FLOP) {
1703 list(cBINOPo->op_first);
1704 return gen_constant_list(o);
79072805
LW
1705 }
1706 case OP_LIST:
11343788 1707 listkids(o);
79072805
LW
1708 break;
1709 case OP_LEAVE:
1710 case OP_LEAVETRY:
5dc0d613 1711 kid = cLISTOPo->op_first;
54310121 1712 list(kid);
25b991bf
VP
1713 kid = kid->op_sibling;
1714 do_kids:
1715 while (kid) {
1716 OP *sib = kid->op_sibling;
c08f093b
VP
1717 if (sib && kid->op_type != OP_LEAVEWHEN)
1718 scalarvoid(kid);
1719 else
54310121 1720 list(kid);
25b991bf 1721 kid = sib;
54310121 1722 }
11206fdd 1723 PL_curcop = &PL_compiling;
54310121 1724 break;
748a9306 1725 case OP_SCOPE:
79072805 1726 case OP_LINESEQ:
25b991bf
VP
1727 kid = cLISTOPo->op_first;
1728 goto do_kids;
79072805 1729 }
11343788 1730 return o;
79072805
LW
1731}
1732
1f676739 1733static OP *
2dd5337b 1734S_scalarseq(pTHX_ OP *o)
79072805 1735{
97aff369 1736 dVAR;
11343788 1737 if (o) {
1496a290
AL
1738 const OPCODE type = o->op_type;
1739
1740 if (type == OP_LINESEQ || type == OP_SCOPE ||
1741 type == OP_LEAVE || type == OP_LEAVETRY)
463ee0b2 1742 {
6867be6d 1743 OP *kid;
11343788 1744 for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling) {
ed6116ce 1745 if (kid->op_sibling) {
463ee0b2 1746 scalarvoid(kid);
ed6116ce 1747 }
463ee0b2 1748 }
3280af22 1749 PL_curcop = &PL_compiling;
79072805 1750 }
11343788 1751 o->op_flags &= ~OPf_PARENS;
3280af22 1752 if (PL_hints & HINT_BLOCK_SCOPE)
11343788 1753 o->op_flags |= OPf_PARENS;
79072805 1754 }
8990e307 1755 else
11343788
MB
1756 o = newOP(OP_STUB, 0);
1757 return o;
79072805
LW
1758}
1759
76e3520e 1760STATIC OP *
cea2e8a9 1761S_modkids(pTHX_ OP *o, I32 type)
79072805 1762{
11343788 1763 if (o && o->op_flags & OPf_KIDS) {
6867be6d 1764 OP *kid;
11343788 1765 for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling)
3ad73efd 1766 op_lvalue(kid, type);
79072805 1767 }
11343788 1768 return o;
79072805
LW
1769}
1770
3ad73efd 1771/*
d164302a
GG
1772=for apidoc finalize_optree
1773
1774This function finalizes the optree. Should be called directly after
1775the complete optree is built. It does some additional
1776checking which can't be done in the normal ck_xxx functions and makes
1777the tree thread-safe.
1778
1779=cut
1780*/
1781void
1782Perl_finalize_optree(pTHX_ OP* o)
1783{
1784 PERL_ARGS_ASSERT_FINALIZE_OPTREE;
1785
1786 ENTER;
1787 SAVEVPTR(PL_curcop);
1788
1789 finalize_op(o);
1790
1791 LEAVE;
1792}
1793
60dde6b2 1794STATIC void
d164302a
GG
1795S_finalize_op(pTHX_ OP* o)
1796{
1797 PERL_ARGS_ASSERT_FINALIZE_OP;
1798
1799#if defined(PERL_MAD) && defined(USE_ITHREADS)
1800 {
1801 /* Make sure mad ops are also thread-safe */
1802 MADPROP *mp = o->op_madprop;
1803 while (mp) {
1804 if (mp->mad_type == MAD_OP && mp->mad_vlen) {
1805 OP *prop_op = (OP *) mp->mad_val;
1806 /* We only need "Relocate sv to the pad for thread safety.", but this
1807 easiest way to make sure it traverses everything */
4dc304e0
FC
1808 if (prop_op->op_type == OP_CONST)
1809 cSVOPx(prop_op)->op_private &= ~OPpCONST_STRICT;
d164302a
GG
1810 finalize_op(prop_op);
1811 }
1812 mp = mp->mad_next;
1813 }
1814 }
1815#endif
1816
1817 switch (o->op_type) {
1818 case OP_NEXTSTATE:
1819 case OP_DBSTATE:
1820 PL_curcop = ((COP*)o); /* for warnings */
1821 break;
1822 case OP_EXEC:
ea31ed66
GG
1823 if ( o->op_sibling
1824 && (o->op_sibling->op_type == OP_NEXTSTATE || o->op_sibling->op_type == OP_DBSTATE)
573d2b1a 1825 && ckWARN(WARN_EXEC))
d164302a 1826 {
ea31ed66
GG
1827 if (o->op_sibling->op_sibling) {
1828 const OPCODE type = o->op_sibling->op_sibling->op_type;
d164302a
GG
1829 if (type != OP_EXIT && type != OP_WARN && type != OP_DIE) {
1830 const line_t oldline = CopLINE(PL_curcop);
ea31ed66 1831 CopLINE_set(PL_curcop, CopLINE((COP*)o->op_sibling));
d164302a
GG
1832 Perl_warner(aTHX_ packWARN(WARN_EXEC),
1833 "Statement unlikely to be reached");
1834 Perl_warner(aTHX_ packWARN(WARN_EXEC),
1835 "\t(Maybe you meant system() when you said exec()?)\n");
1836 CopLINE_set(PL_curcop, oldline);
1837 }
1838 }
1839 }
1840 break;
1841
1842 case OP_GV:
1843 if ((o->op_private & OPpEARLY_CV) && ckWARN(WARN_PROTOTYPE)) {
1844 GV * const gv = cGVOPo_gv;
1845 if (SvTYPE(gv) == SVt_PVGV && GvCV(gv) && SvPVX_const(GvCV(gv))) {
1846 /* XXX could check prototype here instead of just carping */
1847 SV * const sv = sv_newmortal();
1848 gv_efullname3(sv, gv, NULL);
1849 Perl_warner(aTHX_ packWARN(WARN_PROTOTYPE),
1850 "%"SVf"() called too early to check prototype",
1851 SVfARG(sv));
1852 }
1853 }
1854 break;
1855
1856 case OP_CONST:
eb796c7f
GG
1857 if (cSVOPo->op_private & OPpCONST_STRICT)
1858 no_bareword_allowed(o);
1859 /* FALLTHROUGH */
d164302a
GG
1860#ifdef USE_ITHREADS
1861 case OP_HINTSEVAL:
1862 case OP_METHOD_NAMED:
1863 /* Relocate sv to the pad for thread safety.
1864 * Despite being a "constant", the SV is written to,
1865 * for reference counts, sv_upgrade() etc. */
1866 if (cSVOPo->op_sv) {
325e1816 1867 const PADOFFSET ix = pad_alloc(OP_CONST, SVf_READONLY);
d054cdb0
FC
1868 SvREFCNT_dec(PAD_SVl(ix));
1869 PAD_SETSV(ix, cSVOPo->op_sv);
1870 /* XXX I don't know how this isn't readonly already. */
1871 if (!SvIsCOW(PAD_SVl(ix))) SvREADONLY_on(PAD_SVl(ix));
d164302a
GG
1872 cSVOPo->op_sv = NULL;
1873 o->op_targ = ix;
1874 }
1875#endif
1876 break;
1877
1878 case OP_HELEM: {
1879 UNOP *rop;
1880 SV *lexname;
1881 GV **fields;
1882 SV **svp, *sv;
1883 const char *key = NULL;
1884 STRLEN keylen;
1885
1886 if (((BINOP*)o)->op_last->op_type != OP_CONST)
1887 break;
1888
1889 /* Make the CONST have a shared SV */
1890 svp = cSVOPx_svp(((BINOP*)o)->op_last);
54ac81a4 1891 if ((!SvIsCOW_shared_hash(sv = *svp))
649c173f 1892 && SvTYPE(sv) < SVt_PVMG && SvOK(sv) && !SvROK(sv)) {
d164302a
GG
1893 key = SvPV_const(sv, keylen);
1894 lexname = newSVpvn_share(key,
1895 SvUTF8(sv) ? -(I32)keylen : (I32)keylen,
1896 0);
fc2b2dca 1897 SvREFCNT_dec_NN(sv);
d164302a
GG
1898 *svp = lexname;
1899 }
1900
1901 if ((o->op_private & (OPpLVAL_INTRO)))
1902 break;
1903
1904 rop = (UNOP*)((BINOP*)o)->op_first;
1905 if (rop->op_type != OP_RV2HV || rop->op_first->op_type != OP_PADSV)
1906 break;
1907 lexname = *av_fetch(PL_comppad_name, rop->op_first->op_targ, TRUE);
1908 if (!SvPAD_TYPED(lexname))
1909 break;
1910 fields = (GV**)hv_fetchs(SvSTASH(lexname), "FIELDS", FALSE);
1911 if (!fields || !GvHV(*fields))
1912 break;
1913 key = SvPV_const(*svp, keylen);
1914 if (!hv_fetch(GvHV(*fields), key,
1915 SvUTF8(*svp) ? -(I32)keylen : (I32)keylen, FALSE)) {
ce16c625 1916 Perl_croak(aTHX_ "No such class field \"%"SVf"\" "
84cf752c 1917 "in variable %"SVf" of type %"HEKf,
ce16c625 1918 SVfARG(*svp), SVfARG(lexname),
84cf752c 1919 HEKfARG(HvNAME_HEK(SvSTASH(lexname))));
d164302a
GG
1920 }
1921 break;
1922 }
1923
1924 case OP_HSLICE: {
1925 UNOP *rop;
1926 SV *lexname;
1927 GV **fields;
1928 SV **svp;
1929 const char *key;
1930 STRLEN keylen;
1931 SVOP *first_key_op, *key_op;
1932
429a2555
FC
1933 S_scalar_slice_warning(aTHX_ o);
1934
d164302a
GG
1935 if ((o->op_private & (OPpLVAL_INTRO))
1936 /* I bet there's always a pushmark... */
1937 || ((LISTOP*)o)->op_first->op_sibling->op_type != OP_LIST)
1938 /* hmmm, no optimization if list contains only one key. */
1939 break;
1940 rop = (UNOP*)((LISTOP*)o)->op_last;
1941 if (rop->op_type != OP_RV2HV)
1942 break;
1943 if (rop->op_first->op_type == OP_PADSV)
1944 /* @$hash{qw(keys here)} */
1945 rop = (UNOP*)rop->op_first;
1946 else {
1947 /* @{$hash}{qw(keys here)} */
1948 if (rop->op_first->op_type == OP_SCOPE
1949 && cLISTOPx(rop->op_first)->op_last->op_type == OP_PADSV)
1950 {
1951 rop = (UNOP*)cLISTOPx(rop->op_first)->op_last;
1952 }
1953 else
1954 break;
1955 }
1956
1957 lexname = *av_fetch(PL_comppad_name, rop->op_targ, TRUE);
1958 if (!SvPAD_TYPED(lexname))
1959 break;
1960 fields = (GV**)hv_fetchs(SvSTASH(lexname), "FIELDS", FALSE);
1961 if (!fields || !GvHV(*fields))
1962 break;
1963 /* Again guessing that the pushmark can be jumped over.... */
1964 first_key_op = (SVOP*)((LISTOP*)((LISTOP*)o)->op_first->op_sibling)
1965 ->op_first->op_sibling;
1966 for (key_op = first_key_op; key_op;
1967 key_op = (SVOP*)key_op->op_sibling) {
1968 if (key_op->op_type != OP_CONST)
1969 continue;
1970 svp = cSVOPx_svp(key_op);
1971 key = SvPV_const(*svp, keylen);
1972 if (!hv_fetch(GvHV(*fields), key,
1973 SvUTF8(*svp) ? -(I32)keylen : (I32)keylen, FALSE)) {
ce16c625 1974 Perl_croak(aTHX_ "No such class field \"%"SVf"\" "
84cf752c 1975 "in variable %"SVf" of type %"HEKf,
ce16c625 1976 SVfARG(*svp), SVfARG(lexname),
84cf752c 1977 HEKfARG(HvNAME_HEK(SvSTASH(lexname))));
d164302a
GG
1978 }
1979 }
1980 break;
1981 }
429a2555
FC
1982 case OP_ASLICE:
1983 S_scalar_slice_warning(aTHX_ o);
1984 break;
a7fd8ef6 1985
d164302a
GG
1986 case OP_SUBST: {
1987 if (cPMOPo->op_pmreplrootu.op_pmreplroot)
1988 finalize_op(cPMOPo->op_pmreplrootu.op_pmreplroot);
1989 break;
1990 }
1991 default:
1992 break;
1993 }
1994
1995 if (o->op_flags & OPf_KIDS) {
1996 OP *kid;
1997 for (kid = cUNOPo->op_first; kid; kid = kid->op_sibling)
1998 finalize_op(kid);
1999 }
2000}
2001
2002/*
3ad73efd
Z
2003=for apidoc Amx|OP *|op_lvalue|OP *o|I32 type
2004
2005Propagate lvalue ("modifiable") context to an op and its children.
2006I<type> represents the context type, roughly based on the type of op that
2007would do the modifying, although C<local()> is represented by OP_NULL,
2008because it has no op type of its own (it is signalled by a flag on
001c3c51
FC
2009the lvalue op).
2010
2011This function detects things that can't be modified, such as C<$x+1>, and
2012generates errors for them. For example, C<$x+1 = 2> would cause it to be
2013called with an op of type OP_ADD and a C<type> argument of OP_SASSIGN.
2014
2015It also flags things that need to behave specially in an lvalue context,
2016such as C<$$x = 5> which might have to vivify a reference in C<$x>.
3ad73efd
Z
2017
2018=cut
2019*/
ddeae0f1 2020
79072805 2021OP *
d3d7d28f 2022Perl_op_lvalue_flags(pTHX_ OP *o, I32 type, U32 flags)
79072805 2023{
27da23d5 2024 dVAR;
79072805 2025 OP *kid;
ddeae0f1
DM
2026 /* -1 = error on localize, 0 = ignore localize, 1 = ok to localize */
2027 int localize = -1;
79072805 2028
13765c85 2029 if (!o || (PL_parser && PL_parser->error_count))
11343788 2030 return o;
79072805 2031
b162f9ea 2032 if ((o->op_private & OPpTARGET_MY)
7e363e51
GS
2033 && (PL_opargs[o->op_type] & OA_TARGLEX))/* OPp share the meaning */
2034 {
b162f9ea 2035 return o;
7e363e51 2036 }
1c846c1f 2037
5c906035
GG
2038 assert( (o->op_flags & OPf_WANT) != OPf_WANT_VOID );
2039
69974ce6
FC
2040 if (type == OP_PRTF || type == OP_SPRINTF) type = OP_ENTERSUB;
2041
11343788 2042 switch (o->op_type) {
68dc0745 2043 case OP_UNDEF:
3280af22 2044 PL_modcount++;
5dc0d613 2045 return o;
5f05dabc 2046 case OP_STUB:
58bde88d 2047 if ((o->op_flags & OPf_PARENS) || PL_madskills)
5f05dabc
PP
2048 break;
2049 goto nomod;
a0d0e21e 2050 case OP_ENTERSUB:
f79aa60b 2051 if ((type == OP_UNDEF || type == OP_REFGEN || type == OP_LOCK) &&
11343788
MB
2052 !(o->op_flags & OPf_STACKED)) {
2053 o->op_type = OP_RV2CV; /* entersub => rv2cv */
767eda44
FC
2054 /* Both ENTERSUB and RV2CV use this bit, but for different pur-
2055 poses, so we need it clear. */
e26df76a 2056 o->op_private &= ~1;
22c35a8c 2057 o->op_ppaddr = PL_ppaddr[OP_RV2CV];
11343788 2058 assert(cUNOPo->op_first->op_type == OP_NULL);
93c66552 2059 op_null(((LISTOP*)cUNOPo->op_first)->op_first);/* disable pushmark */
79072805
LW
2060 break;
2061 }
cd06dffe 2062 else { /* lvalue subroutine call */
777d9014
FC
2063 o->op_private |= OPpLVAL_INTRO
2064 |(OPpENTERSUB_INARGS * (type == OP_LEAVESUBLV));
e6438c1a 2065 PL_modcount = RETURN_UNLIMITED_NUMBER;
4978d6d9 2066 if (type == OP_GREPSTART || type == OP_ENTERSUB || type == OP_REFGEN) {
d0887bf3 2067 /* Potential lvalue context: */
cd06dffe
GS
2068 o->op_private |= OPpENTERSUB_INARGS;
2069 break;
2070 }
2071 else { /* Compile-time error message: */
2072 OP *kid = cUNOPo->op_first;
2073 CV *cv;
cd06dffe 2074
3ea285d1
AL
2075 if (kid->op_type != OP_PUSHMARK) {
2076 if (kid->op_type != OP_NULL || kid->op_targ != OP_LIST)
2077 Perl_croak(aTHX_
2078 "panic: unexpected lvalue entersub "
2079 "args: type/targ %ld:%"UVuf,
2080 (long)kid->op_type, (UV)kid->op_targ);
2081 kid = kLISTOP->op_first;
2082 }
cd06dffe
GS
2083 while (kid->op_sibling)
2084 kid = kid->op_sibling;
2085 if (!(kid->op_type == OP_NULL && kid->op_targ == OP_RV2CV)) {
cd06dffe
GS
2086 break; /* Postpone until runtime */
2087 }
b2ffa427 2088
cd06dffe
GS
2089 kid = kUNOP->op_first;
2090 if (kid->op_type == OP_NULL && kid->op_targ == OP_RV2SV)
2091 kid = kUNOP->op_first;
b2ffa427 2092 if (kid->op_type == OP_NULL)
cd06dffe
GS
2093 Perl_croak(aTHX_
2094 "Unexpected constant lvalue entersub "
55140b79 2095 "entry via type/targ %ld:%"UVuf,
3d811634 2096 (long)kid->op_type, (UV)kid->op_targ);
cd06dffe 2097 if (kid->op_type != OP_GV) {
cd06dffe
GS
2098 break;
2099 }
b2ffa427 2100
638eceb6 2101 cv = GvCV(kGVOP_gv);
1c846c1f 2102 if (!cv)
da1dff94 2103 break;
cd06dffe
GS
2104 if (CvLVALUE(cv))
2105 break;
2106 }
2107 }
79072805
LW
2108 /* FALL THROUGH */
2109 default:
a0d0e21e 2110 nomod:
f5d552b4 2111 if (flags & OP_LVALUE_NO_CROAK) return NULL;
6fbb66d6 2112 /* grep, foreach, subcalls, refgen */
145b2bbb
FC
2113 if (type == OP_GREPSTART || type == OP_ENTERSUB
2114 || type == OP_REFGEN || type == OP_LEAVESUBLV)
a0d0e21e 2115 break;
cea2e8a9 2116 yyerror(Perl_form(aTHX_ "Can't modify %s in %s",
638bc118 2117 (o->op_type == OP_NULL && (o->op_flags & OPf_SPECIAL)
cd06dffe
GS
2118 ? "do block"
2119 : (o->op_type == OP_ENTERSUB
2120 ? "non-lvalue subroutine call"
53e06cf0 2121 : OP_DESC(o))),
22c35a8c 2122 type ? PL_op_desc[type] : "local"));
11343788 2123 return o;
79072805 2124
a0d0e21e
LW
2125 case OP_PREINC:
2126 case OP_PREDEC:
2127 case OP_POW:
2128 case OP_MULTIPLY:
2129 case OP_DIVIDE:
2130 case OP_MODULO:
2131 case OP_REPEAT:
2132 case OP_ADD:
2133 case OP_SUBTRACT:
2134 case OP_CONCAT:
2135 case OP_LEFT_SHIFT:
2136 case OP_RIGHT_SHIFT:
2137 case OP_BIT_AND:
2138 case OP_BIT_XOR:
2139 case OP_BIT_OR:
2140 case OP_I_MULTIPLY:
2141 case OP_I_DIVIDE:
2142 case OP_I_MODULO:
2143 case OP_I_ADD:
2144 case OP_I_SUBTRACT:
11343788 2145 if (!(o->op_flags & OPf_STACKED))
a0d0e21e 2146 goto nomod;
3280af22 2147 PL_modcount++;
a0d0e21e 2148 break;
b2ffa427 2149
79072805 2150 case OP_COND_EXPR:
ddeae0f1 2151 localize = 1;
11343788 2152 for (kid = cUNOPo->op_first->op_sibling; kid; kid = kid->op_sibling)
3ad73efd 2153 op_lvalue(kid, type);
79072805
LW
2154 break;
2155
2156 case OP_RV2AV:
2157 case OP_RV2HV:
11343788 2158 if (type == OP_REFGEN && o->op_flags & OPf_PARENS) {
e6438c1a 2159 PL_modcount = RETURN_UNLIMITED_NUMBER;
11343788 2160 return o; /* Treat \(@foo) like ordinary list. */
748a9306
LW
2161 }
2162 /* FALL THROUGH */
79072805 2163 case OP_RV2GV:
5dc0d613 2164 if (scalar_mod_type(o, type))
3fe9a6f1 2165 goto nomod;
11343788 2166 ref(cUNOPo->op_first, o->op_type);
79072805 2167 /* FALL THROUGH */
79072805
LW
2168 case OP_ASLICE:
2169 case OP_HSLICE:
ddeae0f1 2170 localize = 1;
78f9721b
SM
2171 /* FALL THROUGH */
2172 case OP_AASSIGN:
631dbaa2
FC
2173 if (type == OP_LEAVESUBLV)
2174 o->op_private |= OPpMAYBE_LVSUB;
2175 /* FALL THROUGH */
93a17b20
LW
2176 case OP_NEXTSTATE:
2177 case OP_DBSTATE:
e6438c1a 2178 PL_modcount = RETURN_UNLIMITED_NUMBER;
79072805 2179 break;
5cae3edb 2180 case OP_KVHSLICE:
6dd3e0f2 2181 case OP_KVASLICE:
5cae3edb
RZ
2182 if (type == OP_LEAVESUBLV)
2183 o->op_private |= OPpMAYBE_LVSUB;
2184 goto nomod;
28c5b5bc
RGS
2185 case OP_AV2ARYLEN:
2186 PL_hints |= HINT_BLOCK_SCOPE;
2187 if (type == OP_LEAVESUBLV)
2188 o->op_private |= OPpMAYBE_LVSUB;
2189 PL_modcount++;
2190 break;
463ee0b2 2191 case OP_RV2SV:
aeea060c 2192 ref(cUNOPo->op_first, o->op_type);
ddeae0f1 2193 localize = 1;
463ee0b2 2194 /* FALL THROUGH */
79072805 2195 case OP_GV:
3280af22 2196 PL_hints |= HINT_BLOCK_SCOPE;
463ee0b2 2197 case OP_SASSIGN:
bf4b1e52
GS
2198 case OP_ANDASSIGN:
2199 case OP_ORASSIGN:
c963b151 2200 case OP_DORASSIGN:
ddeae0f1
DM
2201 PL_modcount++;
2202 break;
2203
8990e307 2204 case OP_AELEMFAST:
93bad3fd 2205 case OP_AELEMFAST_LEX:
6a077020 2206 localize = -1;
3280af22 2207 PL_modcount++;
8990e307
LW
2208 break;
2209
748a9306
LW
2210 case OP_PADAV:
2211 case OP_PADHV:
e6438c1a 2212 PL_modcount = RETURN_UNLIMITED_NUMBER;
5196be3e
MB
2213 if (type == OP_REFGEN && o->op_flags & OPf_PARENS)
2214 return o; /* Treat \(@foo) like ordinary list. */
2215 if (scalar_mod_type(o, type))
3fe9a6f1 2216 goto nomod;
78f9721b
SM
2217 if (type == OP_LEAVESUBLV)
2218 o->op_private |= OPpMAYBE_LVSUB;
748a9306
LW
2219 /* FALL THROUGH */
2220 case OP_PADSV:
3280af22 2221 PL_modcount++;
ddeae0f1 2222 if (!type) /* local() */
5ede95a0
BF
2223 Perl_croak(aTHX_ "Can't localize lexical variable %"SVf,
2224 PAD_COMPNAME_SV(o->op_targ));
463ee0b2
LW
2225 break;
2226
748a9306 2227 case OP_PUSHMARK:
ddeae0f1 2228 localize = 0;
748a9306 2229 break;
b2ffa427 2230
69969c6f 2231 case OP_KEYS:
d8065907 2232 case OP_RKEYS:
fad4a2e4 2233 if (type != OP_SASSIGN && type != OP_LEAVESUBLV)
69969c6f 2234 goto nomod;
5d82c453
GA
2235 goto lvalue_func;
2236 case OP_SUBSTR:
2237 if (o->op_private == 4) /* don't allow 4 arg substr as lvalue */
2238 goto nomod;
5f05dabc 2239 /* FALL THROUGH */
a0d0e21e 2240 case OP_POS:
463ee0b2 2241 case OP_VEC:
fad4a2e4 2242 lvalue_func:
78f9721b
SM
2243 if (type == OP_LEAVESUBLV)
2244 o->op_private |= OPpMAYBE_LVSUB;
11343788 2245 if (o->op_flags & OPf_KIDS)
3ad73efd 2246 op_lvalue(cBINOPo->op_first->op_sibling, type);
463ee0b2 2247 break;
a0d0e21e 2248
463ee0b2
LW
2249 case OP_AELEM:
2250 case OP_HELEM:
11343788 2251 ref(cBINOPo->op_first, o->op_type);
68dc0745 2252 if (type == OP_ENTERSUB &&
5dc0d613
MB
2253 !(o->op_private & (OPpLVAL_INTRO | OPpDEREF)))
2254 o->op_private |= OPpLVAL_DEFER;
78f9721b
SM
2255 if (type == OP_LEAVESUBLV)
2256 o->op_private |= OPpMAYBE_LVSUB;
ddeae0f1 2257 localize = 1;
3280af22 2258 PL_modcount++;
463ee0b2
LW
2259 break;
2260
2261 case OP_SCOPE:
2262 case OP_LEAVE:
2263 case OP_ENTER:
78f9721b 2264 case OP_LINESEQ:
ddeae0f1 2265 localize = 0;
11343788 2266 if (o->op_flags & OPf_KIDS)
3ad73efd 2267 op_lvalue(cLISTOPo->op_last, type);
a0d0e21e
LW
2268 break;
2269
2270 case OP_NULL:
ddeae0f1 2271 localize = 0;
638bc118
GS
2272 if (o->op_flags & OPf_SPECIAL) /* do BLOCK */
2273 goto nomod;
2274 else if (!(o->op_flags & OPf_KIDS))
463ee0b2 2275 break;
11343788 2276 if (o->op_targ != OP_LIST) {
3ad73efd 2277 op_lvalue(cBINOPo->op_first, type);
a0d0e21e
LW
2278 break;
2279 }
2280 /* FALL THROUGH */
463ee0b2 2281 case OP_LIST:
ddeae0f1 2282 localize = 0;
11343788 2283 for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling)
5c906035
GG
2284 /* elements might be in void context because the list is
2285 in scalar context or because they are attribute sub calls */
2286 if ( (kid->op_flags & OPf_WANT) != OPf_WANT_VOID )
2287 op_lvalue(kid, type);
463ee0b2 2288 break;
78f9721b
SM
2289
2290 case OP_RETURN:
2291 if (type != OP_LEAVESUBLV)
2292 goto nomod;
3ad73efd 2293 break; /* op_lvalue()ing was handled by ck_return() */
1efec5ed
FC
2294
2295 case OP_COREARGS:
2296 return o;
463ee0b2 2297 }
58d95175 2298
8be1be90
AMS
2299 /* [20011101.069] File test operators interpret OPf_REF to mean that
2300 their argument is a filehandle; thus \stat(".") should not set
2301 it. AMS 20011102 */
2302 if (type == OP_REFGEN &&
ef69c8fc 2303 PL_check[o->op_type] == Perl_ck_ftst)
8be1be90
AMS
2304 return o;
2305
2306 if (type != OP_LEAVESUBLV)
2307 o->op_flags |= OPf_MOD;
2308
2309 if (type == OP_AASSIGN || type == OP_SASSIGN)
2310 o->op_flags |= OPf_SPECIAL|OPf_REF;
ddeae0f1
DM
2311 else if (!type) { /* local() */
2312 switch (localize) {
2313 case 1:
2314 o->op_private |= OPpLVAL_INTRO;
2315 o->op_flags &= ~OPf_SPECIAL;
2316 PL_hints |= HINT_BLOCK_SCOPE;
2317 break;
2318 case 0:
2319 break;
2320 case -1:
a2a5de95
NC
2321 Perl_ck_warner(aTHX_ packWARN(WARN_SYNTAX),
2322 "Useless localization of %s", OP_DESC(o));
ddeae0f1 2323 }
463ee0b2 2324 }
8be1be90
AMS
2325 else if (type != OP_GREPSTART && type != OP_ENTERSUB
2326 && type != OP_LEAVESUBLV)
2327 o->op_flags |= OPf_REF;
11343788 2328 return o;
463ee0b2
LW
2329}
2330
864dbfa3 2331STATIC bool
5f66b61c 2332S_scalar_mod_type(const OP *o, I32 type)
3fe9a6f1
PP
2333{
2334 switch (type) {
32a60974 2335 case OP_POS:
3fe9a6f1 2336 case OP_SASSIGN:
1efec5ed 2337 if (o && o->op_type == OP_RV2GV)
3fe9a6f1
PP
2338 return FALSE;
2339 /* FALL THROUGH */
2340 case OP_PREINC:
2341 case OP_PREDEC:
2342 case OP_POSTINC:
2343 case OP_POSTDEC:
2344 case OP_I_PREINC:
2345 case OP_I_PREDEC:
2346 case OP_I_POSTINC:
2347 case OP_I_POSTDEC:
2348 case OP_POW:
2349 case OP_MULTIPLY:
2350 case OP_DIVIDE:
2351 case OP_MODULO:
2352 case OP_REPEAT:
2353 case OP_ADD:
2354 case OP_SUBTRACT:
2355 case OP_I_MULTIPLY:
2356 case OP_I_DIVIDE:
2357 case OP_I_MODULO:
2358 case OP_I_ADD:
2359 case OP_I_SUBTRACT:
2360 case OP_LEFT_SHIFT:
2361 case OP_RIGHT_SHIFT:
2362 case OP_BIT_AND:
2363 case OP_BIT_XOR:
2364 case OP_BIT_OR:
2365 case OP_CONCAT:
2366 case OP_SUBST:
2367 case OP_TRANS:
bb16bae8 2368 case OP_TRANSR:
49e9fbe6
GS
2369 case OP_READ:
2370 case OP_SYSREAD:
2371 case OP_RECV:
bf4b1e52
GS
2372 case OP_ANDASSIGN:
2373 case OP_ORASSIGN:
410d09fe 2374 case OP_DORASSIGN:
3fe9a6f1
PP
2375 return TRUE;
2376 default:
2377 return FALSE;
2378 }
2379}
2380
35cd451c 2381STATIC bool
5f66b61c 2382S_is_handle_constructor(const OP *o, I32 numargs)
35cd451c 2383{
7918f24d
NC
2384 PERL_ARGS_ASSERT_IS_HANDLE_CONSTRUCTOR;
2385
35cd451c
GS
2386 switch (o->op_type) {
2387 case OP_PIPE_OP:
2388 case OP_SOCKPAIR:
504618e9 2389 if (numargs == 2)
35cd451c
GS
2390 return TRUE;
2391 /* FALL THROUGH */
2392 case OP_SYSOPEN:
2393 case OP_OPEN:
ded8aa31 2394 case OP_SELECT: /* XXX c.f. SelectSaver.pm */
35cd451c
GS
2395 case OP_SOCKET:
2396 case OP_OPEN_DIR:
2397 case OP_ACCEPT:
504618e9 2398 if (numargs == 1)
35cd451c 2399 return TRUE;
5f66b61c 2400 /* FALLTHROUGH */
35cd451c
GS
2401 default:
2402 return FALSE;
2403 }
2404}
2405
0d86688d
NC
2406static OP *
2407S_refkids(pTHX_ OP *o, I32 type)
463ee0b2 2408{
11343788 2409 if (o && o->op_flags & OPf_KIDS) {
6867be6d 2410 OP *kid;
11343788 2411 for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling)
463ee0b2
LW
2412 ref(kid, type);
2413 }
11343788 2414 return o;
463ee0b2
LW
2415}
2416
2417OP *
e4c5ccf3 2418Perl_doref(pTHX_ OP *o, I32 type, bool set_op_ref)
463ee0b2 2419{
27da23d5 2420 dVAR;
463ee0b2 2421 OP *kid;
463ee0b2 2422
7918f24d
NC
2423 PERL_ARGS_ASSERT_DOREF;
2424
13765c85 2425 if (!o || (PL_parser && PL_parser->error_count))
11343788 2426 return o;
463ee0b2 2427
11343788 2428 switch (o->op_type) {
a0d0e21e 2429 case OP_ENTERSUB:
f4df43b5 2430 if ((type == OP_EXISTS || type == OP_DEFINED) &&
11343788
MB
2431 !(o->op_flags & OPf_STACKED)) {
2432 o->op_type = OP_RV2CV; /* entersub => rv2cv */
22c35a8c 2433 o->op_ppaddr = PL_ppaddr[OP_RV2CV];
11343788 2434 assert(cUNOPo->op_first->op_type == OP_NULL);
93c66552 2435 op_null(((LISTOP*)cUNOPo->op_first)->op_first); /* disable pushmark */
11343788 2436 o->op_flags |= OPf_SPECIAL;
e26df76a 2437 o->op_private &= ~1;
8990e307 2438 }
767eda44 2439 else if (type == OP_RV2SV || type == OP_RV2AV || type == OP_RV2HV){
0e9700df
GG
2440 o->op_private |= (type == OP_RV2AV ? OPpDEREF_AV
2441 : type == OP_RV2HV ? OPpDEREF_HV
2442 : OPpDEREF_SV);
767eda44
FC
2443 o->op_flags |= OPf_MOD;
2444 }
2445
8990e307 2446 break;
aeea060c 2447
463ee0b2 2448 case OP_COND_EXPR:
11343788 2449 for (kid = cUNOPo->op_first->op_sibling; kid; kid = kid->op_sibling)
e4c5ccf3 2450 doref(kid, type, set_op_ref);
463ee0b2 2451 break;
8990e307 2452 case OP_RV2SV:
35cd451c
GS
2453 if (type == OP_DEFINED)
2454 o->op_flags |= OPf_SPECIAL; /* don't create GV */
e4c5ccf3 2455 doref(cUNOPo->op_first, o->op_type, set_op_ref);
4633a7c4
LW
2456 /* FALL THROUGH */
2457 case OP_PADSV:
5f05dabc 2458 if (type == OP_RV2SV || type == OP_RV2AV || type == OP_RV2HV) {
5dc0d613
MB
2459 o->op_private |= (type == OP_RV2AV ? OPpDEREF_AV
2460 : type == OP_RV2HV ? OPpDEREF_HV
2461 : OPpDEREF_SV);
11343788 2462 o->op_flags |= OPf_MOD;
a0d0e21e 2463 }
8990e307 2464 break;
1c846c1f 2465
463ee0b2
LW
2466 case OP_RV2AV:
2467 case OP_RV2HV:
e4c5ccf3
RH
2468 if (set_op_ref)
2469 o->op_flags |= OPf_REF;
8990e307 2470 /* FALL THROUGH */
463ee0b2 2471 case OP_RV2GV:
35cd451c
GS
2472 if (type == OP_DEFINED)
2473 o->op_flags |= OPf_SPECIAL; /* don't create GV */
e4c5ccf3 2474 doref(cUNOPo->op_first, o->op_type, set_op_ref);
463ee0b2 2475 break;
8990e307 2476
463ee0b2
LW
2477 case OP_PADAV:
2478 case OP_PADHV:
e4c5ccf3
RH
2479 if (set_op_ref)
2480 o->op_flags |= OPf_REF;
79072805 2481 break;
aeea060c 2482
8990e307 2483 case OP_SCALAR:
79072805 2484 case OP_NULL:
518618af 2485 if (!(o->op_flags & OPf_KIDS) || type == OP_DEFINED)
463ee0b2 2486 break;
e4c5ccf3 2487 doref(cBINOPo->op_first, type, set_op_ref);
79072805
LW
2488 break;
2489 case OP_AELEM:
2490 case OP_HELEM:
e4c5ccf3 2491 doref(cBINOPo->op_first, o->op_type, set_op_ref);
5f05dabc 2492 if (type == OP_RV2SV || type == OP_RV2AV || type == OP_RV2HV) {
5dc0d613
MB
2493 o->op_private |= (type == OP_RV2AV ? OPpDEREF_AV
2494 : type == OP_RV2HV ? OPpDEREF_HV
2495 : OPpDEREF_SV);
11343788 2496 o->op_flags |= OPf_MOD;
8990e307 2497 }
79072805
LW
2498 break;
2499
463ee0b2 2500 case OP_SCOPE:
79072805 2501 case OP_LEAVE:
e4c5ccf3
RH
2502 set_op_ref = FALSE;
2503 /* FALL THROUGH */
79072805 2504 case OP_ENTER:
8990e307 2505 case OP_LIST:
11343788 2506 if (!(o->op_flags & OPf_KIDS))
79072805 2507 break;
e4c5ccf3 2508 doref(cLISTOPo->op_last, type, set_op_ref);
79072805 2509 break;
a0d0e21e
LW
2510 default:
2511 break;
79072805 2512 }
11343788 2513 return scalar(o);
8990e307 2514
79072805
LW
2515}
2516
09bef843
SB
2517STATIC OP *
2518S_dup_attrlist(pTHX_ OP *o)
2519{
97aff369 2520 dVAR;
0bd48802 2521 OP *rop;
09bef843 2522
7918f24d
NC
2523 PERL_ARGS_ASSERT_DUP_ATTRLIST;
2524
09bef843
SB
2525 /* An attrlist is either a simple OP_CONST or an OP_LIST with kids,
2526 * where the first kid is OP_PUSHMARK and the remaining ones
2527 * are OP_CONST. We need to push the OP_CONST values.
2528 */
2529 if (o->op_type == OP_CONST)
b37c2d43 2530 rop = newSVOP(OP_CONST, o->op_flags, SvREFCNT_inc_NN(cSVOPo->op_sv));
eb8433b7
NC
2531#ifdef PERL_MAD
2532 else if (o->op_type == OP_NULL)
1d866c12 2533 rop = NULL;
eb8433b7 2534#endif
09bef843
SB
2535 else {
2536 assert((o->op_type == OP_LIST) && (o->op_flags & OPf_KIDS));
5f66b61c 2537 rop = NULL;
09bef843
SB
2538 for (o = cLISTOPo->op_first; o; o=o->op_sibling) {
2539 if (o->op_type == OP_CONST)
2fcb4757 2540 rop = op_append_elem(OP_LIST, rop,
09bef843 2541 newSVOP(OP_CONST, o->op_flags,
b37c2d43 2542 SvREFCNT_inc_NN(cSVOPo->op_sv)));
09bef843
SB
2543 }
2544 }
2545 return rop;
2546}
2547
2548STATIC void
ad0dc73b 2549S_apply_attrs(pTHX_ HV *stash, SV *target, OP *attrs)
09bef843 2550{
27da23d5 2551 dVAR;
ad0dc73b 2552 SV * const stashsv = stash ? newSVhek(HvNAME_HEK(stash)) : &PL_sv_no;
09bef843 2553
7918f24d
NC
2554 PERL_ARGS_ASSERT_APPLY_ATTRS;
2555
09bef843
SB
2556 /* fake up C<use attributes $pkg,$rv,@attrs> */
2557 ENTER; /* need to protect against side-effects of 'use' */
e4783991 2558
09bef843 2559#define ATTRSMODULE "attributes"
95f0a2f1
SB
2560#define ATTRSMODULE_PM "attributes.pm"
2561
ad0dc73b 2562 Perl_load_module(aTHX_ PERL_LOADMOD_IMPORT_OPS,
6136c704
AL
2563 newSVpvs(ATTRSMODULE),
2564 NULL,
2fcb4757 2565 op_prepend_elem(OP_LIST,
95f0a2f1 2566 newSVOP(OP_CONST, 0, stashsv),
2fcb4757 2567 op_prepend_elem(OP_LIST,
95f0a2f1
SB
2568 newSVOP(OP_CONST, 0,
2569 newRV(target)),
2570 dup_attrlist(attrs))));
09bef843
SB
2571 LEAVE;
2572}
2573
95f0a2f1
SB
2574STATIC void
2575S_apply_attrs_my(pTHX_ HV *stash, OP *target, OP *attrs, OP **imopsp)
2576{
97aff369 2577 dVAR;
95f0a2f1 2578 OP *pack, *imop, *arg;
ad0dc73b 2579 SV *meth, *stashsv, **svp;
95f0a2f1 2580
7918f24d
NC
2581 PERL_ARGS_ASSERT_APPLY_ATTRS_MY;
2582
95f0a2f1
SB
2583 if (!attrs)
2584 return;
2585
2586 assert(target->op_type == OP_PADSV ||
2587 target->op_type == OP_PADHV ||
2588 target->op_type == OP_PADAV);
2589
2590 /* Ensure that attributes.pm is loaded. */
ad0dc73b
FC
2591 ENTER; /* need to protect against side-effects of 'use' */
2592 /* Don't force the C<use> if we don't need it. */
2593 svp = hv_fetchs(GvHVn(PL_incgv), ATTRSMODULE_PM, FALSE);
2594 if (svp && *svp != &PL_sv_undef)
2595 NOOP; /* already in %INC */
2596 else
2597 Perl_load_module(aTHX_ PERL_LOADMOD_NOIMPORT,
2598 newSVpvs(ATTRSMODULE), NULL);
2599 LEAVE;
95f0a2f1
SB
2600
2601 /* Need package name for method call. */
6136c704 2602 pack = newSVOP(OP_CONST, 0, newSVpvs(ATTRSMODULE));
95f0a2f1
SB
2603
2604 /* Build up the real arg-list. */
5aaec2b4
NC
2605 stashsv = stash ? newSVhek(HvNAME_HEK(stash)) : &PL_sv_no;
2606
95f0a2f1
SB
2607 arg = newOP(OP_PADSV, 0);
2608 arg->op_targ = target->op_targ;
2fcb4757 2609 arg = op_prepend_elem(OP_LIST,
95f0a2f1 2610 newSVOP(OP_CONST, 0, stashsv),
2fcb4757 2611 op_prepend_elem(OP_LIST,
95f0a2f1 2612 newUNOP(OP_REFGEN, 0,
3ad73efd 2613 op_lvalue(arg, OP_REFGEN)),
95f0a2f1
SB
2614 dup_attrlist(attrs)));
2615
2616 /* Fake up a method call to import */
18916d0d 2617 meth = newSVpvs_share("import");
95f0a2f1 2618 imop = convert(OP_ENTERSUB, OPf_STACKED|OPf_SPECIAL|OPf_WANT_VOID,
2fcb4757
Z
2619 op_append_elem(OP_LIST,
2620 op_prepend_elem(OP_LIST, pack, list(arg)),
95f0a2f1 2621 newSVOP(OP_METHOD_NAMED, 0, meth)));
95f0a2f1
SB
2622
2623 /* Combine the ops. */
2fcb4757 2624 *imopsp = op_append_elem(OP_LIST, *imopsp, imop);
95f0a2f1
SB
2625}
2626
2627/*
2628=notfor apidoc apply_attrs_string
2629
2630Attempts to apply a list of attributes specified by the C<attrstr> and
2631C<len> arguments to the subroutine identified by the C<cv> argument which
2632is expected to be associated with the package identified by the C<stashpv>
2633argument (see L<attributes>). It gets this wrong, though, in that it
2634does not correctly identify the boundaries of the individual attribute
2635specifications within C<attrstr>. This is not really intended for the
2636public API, but has to be listed here for systems such as AIX which
2637need an explicit export list for symbols. (It's called from XS code
2638in support of the C<ATTRS:> keyword from F<xsubpp>.) Patches to fix it
2639to respect attribute syntax properly would be welcome.
2640
2641=cut
2642*/
2643
be3174d2 2644void
6867be6d
AL
2645Perl_apply_attrs_string(pTHX_ const char *stashpv, CV *cv,
2646 const char *attrstr, STRLEN len)
be3174d2 2647{
5f66b61c 2648 OP *attrs = NULL;
be3174d2 2649
7918f24d
NC
2650 PERL_ARGS_ASSERT_APPLY_ATTRS_STRING;
2651
be3174d2
GS
2652 if (!len) {
2653 len = strlen(attrstr);
2654 }
2655
2656 while (len) {
2657 for (; isSPACE(*attrstr) && len; --len, ++attrstr) ;
2658 if (len) {
890ce7af 2659 const char * const sstr = attrstr;
be3174d2 2660 for (; !isSPACE(*attrstr) && len; --len, ++attrstr) ;
2fcb4757 2661 attrs = op_append_elem(OP_LIST, attrs,
be3174d2
GS
2662 newSVOP(OP_CONST, 0,
2663 newSVpvn(sstr, attrstr-sstr)));
2664 }
2665 }
2666
2667 Perl_load_module(aTHX_ PERL_LOADMOD_IMPORT_OPS,
6136c704 2668 newSVpvs(ATTRSMODULE),
2fcb4757 2669 NULL, op_prepend_elem(OP_LIST,
be3174d2 2670 newSVOP(OP_CONST, 0, newSVpv(stashpv,0)),
2fcb4757 2671 op_prepend_elem(OP_LIST,
be3174d2 2672 newSVOP(OP_CONST, 0,
ad64d0ec 2673 newRV(MUTABLE_SV(cv))),
be3174d2
GS
2674 attrs)));
2675}
2676
09bef843 2677STATIC OP *
95f0a2f1 2678S_my_kid(pTHX_ OP *o, OP *attrs, OP **imopsp)
93a17b20 2679{
97aff369 2680 dVAR;
93a17b20 2681 I32 type;
a1fba7eb 2682 const bool stately = PL_parser && PL_parser->in_my == KEY_state;
93a17b20 2683
7918f24d
NC
2684 PERL_ARGS_ASSERT_MY_KID;
2685
13765c85 2686 if (!o || (PL_parser && PL_parser->error_count))
11343788 2687 return o;
93a17b20 2688
bc61e325 2689 type = o->op_type;
eb8433b7
NC
2690 if (PL_madskills && type == OP_NULL && o->op_flags & OPf_KIDS) {
2691 (void)my_kid(cUNOPo->op_first, attrs, imopsp);
2692 return o;
2693 }
2694
93a17b20 2695 if (type == OP_LIST) {
6867be6d 2696 OP *kid;
11343788 2697 for (kid = cLISTOPo->op_first; kid; kid = kid->op_sibling)
95f0a2f1 2698 my_kid(kid, attrs, imopsp);
0865059d 2699 return o;
8b8c1fb9 2700 } else if (type == OP_UNDEF || type == OP_STUB) {
7766148a 2701 return o;
77ca0c92
LW
2702 } else if (type == OP_RV2SV || /* "our" declaration */
2703 type == OP_RV2AV ||
2704 type == OP_RV2HV) { /* XXX does this let anything illegal in? */
1ce0b88c 2705 if (cUNOPo->op_first->op_type != OP_GV) { /* MJD 20011224 */
fab01b8e 2706 yyerror(Perl_form(aTHX_ "Can't declare %s in \"%s\"",
952306ac 2707 OP_DESC(o),
12bd6ede
DM
2708 PL_parser->in_my == KEY_our
2709 ? "our"
2710 : PL_parser->in_my == KEY_state ? "state" : "my"));
1ce0b88c 2711 } else if (attrs) {
551405c4 2712 GV * const gv = cGVOPx_gv(cUNOPo->op_first);
12bd6ede
DM
2713 PL_parser->in_my = FALSE;
2714 PL_parser->in_my_stash = NULL;
1ce0b88c
RGS
2715 apply_attrs(GvSTASH(gv),
2716 (type == OP_RV2SV ? GvSV(gv) :
ad64d0ec
NC
2717 type == OP_RV2AV ? MUTABLE_SV(GvAV(gv)) :
2718 type == OP_RV2HV ? MUTABLE_SV(GvHV(gv)) : MUTABLE_SV(gv)),
ad0dc73b 2719 attrs);
1ce0b88c 2720 }
192587c2 2721 o->op_private |= OPpOUR_INTRO;
77ca0c92 2722 return o;
95f0a2f1
SB
2723 }
2724 else if (type != OP_PADSV &&
93a17b20
LW
2725 type != OP_PADAV &&
2726 type != OP_PADHV &&
2727 type != OP_PUSHMARK)
2728 {
eb64745e 2729 yyerror(Perl_form(aTHX_ "Can't declare %s in \"%s\"",
53e06cf0 2730 OP_DESC(o),
12bd6ede
DM
2731 PL_parser->in_my == KEY_our
2732 ? "our"
2733 : PL_parser->in_my == KEY_state ? "state" : "my"));
11343788 2734 return o;
93a17b20 2735 }
09bef843
SB
2736 else if (attrs && type != OP_PUSHMARK) {
2737 HV *stash;
09bef843 2738
12bd6ede
DM
2739 PL_parser->in_my = FALSE;
2740 PL_parser->in_my_stash = NULL;
eb64745e 2741
09bef843 2742 /* check for C<my Dog $spot> when deciding package */
dd2155a4
DM
2743 stash = PAD_COMPNAME_TYPE(o->op_targ);
2744 if (!stash)
09bef843 2745 stash = PL_curstash;
95f0a2f1 2746 apply_attrs_my(stash, o, attrs, imopsp);
09bef843 2747 }
11343788
MB
2748 o->op_flags |= OPf_MOD;
2749 o->op_private |= OPpLVAL_INTRO;
a1fba7eb 2750 if (stately)
952306ac 2751 o->op_private |= OPpPAD_STATE;
11343788 2752 return o;
93a17b20
LW
2753}
2754
2755OP *
09bef843
SB
2756Perl_my_attrs(pTHX_ OP *o, OP *attrs)
2757{
97aff369 2758 dVAR;
0bd48802 2759 OP *rops;
95f0a2f1
SB
2760 int maybe_scalar = 0;
2761
7918f24d
NC
2762 PERL_ARGS_ASSERT_MY_ATTRS;
2763
d2be0de5 2764/* [perl #17376]: this appears to be premature, and results in code such as
c754c3d7 2765 C< our(%x); > executing in list mode rather than void mode */
d2be0de5 2766#if 0
09bef843
SB
2767 if (o->op_flags & OPf_PARENS)
2768 list(o);
95f0a2f1
SB
2769 else
2770 maybe_scalar = 1;
d2be0de5
YST
2771#else
2772 maybe_scalar = 1;
2773#endif
09bef843
SB
2774 if (attrs)
2775 SAVEFREEOP(attrs);
5f66b61c 2776 rops = NULL;
95f0a2f1
SB
2777 o = my_kid(o, attrs, &rops);
2778 if (rops) {
2779 if (maybe_scalar && o->op_type == OP_PADSV) {
2fcb4757 2780 o = scalar(op_append_list(OP_LIST, rops, o));
95f0a2f1
SB
2781 o->op_private |= OPpLVAL_INTRO;
2782 }
f5d1ed10
FC
2783 else {
2784 /* The listop in rops might have a pushmark at the beginning,
2785 which will mess up list assignment. */
2786 LISTOP * const lrops = (LISTOP *)rops; /* for brevity */
2787 if (rops->op_type == OP_LIST &&
2788 lrops->op_first && lrops->op_first->op_type == OP_PUSHMARK)
2789 {
2790 OP * const pushmark = lrops->op_first;
2791 lrops->op_first = pushmark->op_sibling;
2792 op_free(pushmark);
2793 }
2fcb4757 2794 o = op_append_list(OP_LIST, o, rops);
f5d1ed10 2795 }
95f0a2f1 2796 }
12bd6ede
DM
2797 PL_parser->in_my = FALSE;
2798 PL_parser->in_my_stash = NULL;
eb64745e 2799 return o;
09bef843
SB
2800}
2801
2802OP *
864dbfa3 2803Perl_sawparens(pTHX_ OP *o)
79072805 2804{
96a5add6 2805 PERL_UNUSED_CONTEXT;
79072805
LW
2806 if (o)
2807 o->op_flags |= OPf_PARENS;
2808 return o;
2809}
2810
2811OP *
864dbfa3 2812Perl_bind_match(pTHX_ I32 type, OP *left, OP *right)
79072805 2813{
11343788 2814 OP *o;
59f00321 2815 bool ismatchop = 0;
1496a290
AL
2816 const OPCODE ltype = left->op_type;
2817 const OPCODE rtype = right->op_type;
79072805 2818
7918f24d
NC
2819 PERL_ARGS_ASSERT_BIND_MATCH;
2820
1496a290
AL
2821 if ( (ltype == OP_RV2AV || ltype == OP_RV2HV || ltype == OP_PADAV
2822 || ltype == OP_PADHV) && ckWARN(WARN_MISC))
041457d9 2823 {
1496a290 2824 const char * const desc
bb16bae8
FC
2825 = PL_op_desc[(
2826 rtype == OP_SUBST || rtype == OP_TRANS
2827 || rtype == OP_TRANSR
2828 )
666ea192 2829 ? (int)rtype : OP_MATCH];
c6771ab6 2830 const bool isary = ltype == OP_RV2AV || ltype == OP_PADAV;
c6771ab6 2831 SV * const name =
0920b7fa 2832 S_op_varname(aTHX_ left);
c6771ab6
FC
2833 if (name)
2834 Perl_warner(aTHX_ packWARN(WARN_MISC),
2835 "Applying %s to %"SVf" will act on scalar(%"SVf")",
2836 desc, name, name);
2837 else {
2838 const char * const sample = (isary
666ea192 2839 ? "@array" : "%hash");
c6771ab6 2840 Perl_warner(aTHX_ packWARN(WARN_MISC),
1c846c1f 2841 "Applying %s to %s will act on scalar(%s)",
599cee73 2842 desc, sample, sample);
c6771ab6 2843 }
2ae324a7
PP
2844 }
2845
1496a290 2846 if (rtype == OP_CONST &&
5cc9e5c9
RH
2847 cSVOPx(right)->op_private & OPpCONST_BARE &&
2848 cSVOPx(right)->op_private & OPpCONST_STRICT)
2849 {
2850 no_bareword_allowed(right);
2851 }
2852
bb16bae8 2853 /* !~ doesn't make sense with /r, so error on it for now */
4f4d7508
DC
2854 if (rtype == OP_SUBST && (cPMOPx(right)->op_pmflags & PMf_NONDESTRUCT) &&
2855 type == OP_NOT)
2856 yyerror("Using !~ with s///r doesn't make sense");
bb16bae8
FC
2857 if (rtype == OP_TRANSR && type == OP_NOT)
2858 yyerror("Using !~ with tr///r doesn't make sense");
4f4d7508 2859
2474a784
FC
2860 ismatchop = (rtype == OP_MATCH ||
2861 rtype == OP_SUBST ||
bb16bae8 2862 rtype == OP_TRANS || rtype == OP_TRANSR)
2474a784 2863 && !(right->op_flags & OPf_SPECIAL);
59f00321
RGS
2864 if (ismatchop && right->op_private & OPpTARGET_MY) {
2865 right->op_targ = 0;
2866 right->op_private &= ~OPpTARGET_MY;
2867 }
2868 if (!(right->op_flags & OPf_STACKED) && ismatchop) {
1496a290
AL
2869 OP *newleft;
2870
79072805 2871 right->op_flags |= OPf_STACKED;
bb16bae8 2872 if (rtype != OP_MATCH && rtype != OP_TRANSR &&
1496a290 2873 ! (rtype == OP_TRANS &&
4f4d7508
DC
2874 right->op_private & OPpTRANS_IDENTICAL) &&
2875 ! (rtype == OP_SUBST &&
2876 (cPMOPx(right)->op_pmflags & PMf_NONDESTRUCT)))
3ad73efd 2877 newleft = op_lvalue(left, rtype);
1496a290
AL
2878 else
2879 newleft = left;
bb16bae8 2880 if (right->op_type == OP_TRANS || right->op_type == OP_TRANSR)
1496a290 2881 o = newBINOP(OP_NULL, OPf_STACKED, scalar(newleft), right);
79072805 2882 else
2fcb4757 2883 o = op_prepend_elem(rtype, scalar(newleft), right);
79072805 2884 if (type == OP_NOT)
11343788
MB
2885 return newUNOP(OP_NOT, 0, scalar(o));
2886 return o;
79072805
LW
2887 }
2888 else
2889 return bind_match(type, left,
d63c20f2 2890 pmruntime(newPMOP(OP_MATCH, 0), right, 0, 0));
79072805
LW
2891}
2892
2893OP *
864dbfa3 2894Perl_invert(pTHX_ OP *o)
79072805 2895{
11343788 2896 if (!o)
1d866c12 2897 return NULL;
11343788 2898 return newUNOP(OP_NOT, OPf_SPECIAL, scalar(o));
79072805
LW
2899}
2900
3ad73efd
Z
2901/*
2902=for apidoc Amx|OP *|op_scope|OP *o
2903
2904Wraps up an op tree with some additional ops so that at runtime a dynamic
2905scope will be created. The original ops run in the new dynamic scope,
2906and then, provided that they exit normally, the scope will be unwound.
2907The additional ops used to create and unwind the dynamic scope will
2908normally be an C<enter>/C<leave> pair, but a C<scope> op may be used
2909instead if the ops are simple enough to not need the full dynamic scope
2910structure.
2911
2912=cut
2913*/
2914
79072805 2915OP *
3ad73efd 2916Perl_op_scope(pTHX_ OP *o)
79072805 2917{
27da23d5 2918 dVAR;
79072805 2919 if (o) {
284167a5 2920 if (o->op_flags & OPf_PARENS || PERLDB_NOOPT || TAINTING_get) {
2fcb4757 2921 o = op_prepend_elem(OP_LINESEQ, newOP(OP_ENTER, 0), o);
463ee0b2 2922 o->op_type = OP_LEAVE;
22c35a8c 2923 o->op_ppaddr = PL_ppaddr[OP_LEAVE];
463ee0b2 2924 }
fdb22418
HS
2925 else if (o->op_type == OP_LINESEQ) {
2926 OP *kid;
2927 o->op_type = OP_SCOPE;
2928 o->op_ppaddr = PL_ppaddr[OP_SCOPE];
2929 kid = ((LISTOP*)o)->op_first;
59110972 2930 if (kid->op_type == OP_NEXTSTATE || kid->op_type == OP_DBSTATE) {
fdb22418 2931 op_null(kid);
59110972
RH
2932
2933 /* The following deals with things like 'do {1 for 1}' */
2934 kid = kid->op_sibling;
2935 if (kid &&
2936 (kid->op_type == OP_NEXTSTATE || kid->op_type == OP_DBSTATE))
2937 op_null(kid);
2938 }
463ee0b2 2939 }
fdb22418 2940 else
5f66b61c 2941 o = newLISTOP(OP_SCOPE, 0, o, NULL);
79072805
LW
2942 }
2943 return o;
2944}
1930840b 2945
705fe0e5
FC
2946OP *
2947Perl_op_unscope(pTHX_ OP *o)
2948{
2949 if (o && o->op_type == OP_LINESEQ) {
2950 OP *kid = cLISTOPo->op_first;
2951 for(; kid; kid = kid->op_sibling)
2952 if (kid->op_type == OP_NEXTSTATE || kid->op_type == OP_DBSTATE)
2953 op_null(kid);
2954 }
2955 return o;
2956}
2957
a0d0e21e 2958int
864dbfa3 2959Perl_block_start(pTHX_ int full)
79072805 2960{
97aff369 2961 dVAR;
73d840c0 2962 const int retval = PL_savestack_ix;
1930840b 2963
dd2155a4 2964 pad_block_start(full);
b3ac6de7 2965 SAVEHINTS();
3280af22 2966 PL_hints &= ~HINT_BLOCK_SCOPE;
68da3b2f 2967 SAVECOMPILEWARNINGS();
72dc9ed5 2968 PL_compiling.cop_warnings = DUP_WARNINGS(PL_compiling.cop_warnings);
1930840b 2969
a88d97bf 2970 CALL_BLOCK_HOOKS(bhk_start, full);
1930840b 2971
a0d0e21e
LW
2972 return retval;
2973}
2974
2975OP*
864dbfa3 2976Perl_block_end(pTHX_ I32 floor, OP *seq)
a0d0e21e 2977{
97aff369 2978 dVAR;
6867be6d 2979 const int needblockscope = PL_hints & HINT_BLOCK_SCOPE;
1930840b 2980 OP* retval = scalarseq(seq);
6d5c2147 2981 OP *o;
1930840b 2982
a88d97bf 2983 CALL_BLOCK_HOOKS(bhk_pre_end, &retval);
1930840b 2984
e9818f4e 2985 LEAVE_SCOPE(floor);
a0d0e21e 2986 if (needblockscope)
3280af22 2987 PL_hints |= HINT_BLOCK_SCOPE; /* propagate out */
6d5c2147
FC
2988 o = pad_leavemy();
2989
2990 if (o) {
2991 /* pad_leavemy has created a sequence of introcv ops for all my
2992 subs declared in the block. We have to replicate that list with
2993 clonecv ops, to deal with this situation:
2994
2995 sub {
2996 my sub s1;
2997 my sub s2;
2998 sub s1 { state sub foo { \&s2 } }
2999 }->()
3000
3001 Originally, I was going to have introcv clone the CV and turn
3002 off the stale flag. Since &s1 is declared before &s2, the
3003 introcv op for &s1 is executed (on sub entry) before the one for
3004 &s2. But the &foo sub inside &s1 (which is cloned when &s1 is
3005 cloned, since it is a state sub) closes over &s2 and expects
3006 to see it in its outer CV’s pad. If the introcv op clones &s1,
3007 then &s2 is still marked stale. Since &s1 is not active, and
3008 &foo closes over &s1’s implicit entry for &s2, we get a ‘Varia-
3009 ble will not stay shared’ warning. Because it is the same stub
3010 that will be used when the introcv op for &s2 is executed, clos-
3011 ing over it is safe. Hence, we have to turn off the stale flag
3012 on all lexical subs in the block before we clone any of them.
3013 Hence, having introcv clone the sub cannot work. So we create a
3014 list of ops like this:
3015
3016 lineseq
3017 |
3018 +-- introcv
3019 |
3020 +-- introcv
3021 |
3022 +-- introcv
3023 |
3024 .
3025 .
3026 .
3027 |
3028 +-- clonecv
3029 |
3030 +-- clonecv
3031 |
3032 +-- clonecv
3033 |
3034 .
3035 .
3036 .
3037 */
3038 OP *kid = o->op_flags & OPf_KIDS ? cLISTOPo->op_first : o;
3039 OP * const last = o->op_flags & OPf_KIDS ? cLISTOPo->op_last : o;
3040 for (;; kid = kid->op_sibling) {
3041 OP *newkid = newOP(OP_CLONECV, 0);
3042 newkid->op_targ = kid->op_targ;
3043 o = op_append_elem(OP_LINESEQ, o, newkid);
3044 if (kid == last) break;
3045 }
3046 retval = op_prepend_elem(OP_LINESEQ, o, retval);
3047 }
1930840b 3048
a88d97bf 3049 CALL_BLOCK_HOOKS(bhk_post_end, &retval);
1930840b 3050
a0d0e21e
LW
3051 return retval;
3052}
3053
fd85fad2
BM
3054/*
3055=head1 Compile-time scope hooks
3056
3e4ddde5 3057=for apidoc Aox||blockhook_register
fd85fad2
BM
3058
3059Register a set of hooks to be called when the Perl lexical scope changes
3060at compile time. See L<perlguts/"Compile-time scope hooks">.
3061
3062=cut
3063*/
3064
bb6c22e7
BM
3065void
3066Perl_blockhook_register(pTHX_ BHK *hk)
3067{
3068 PERL_ARGS_ASSERT_BLOCKHOOK_REGISTER;
3069
3070 Perl_av_create_and_push(aTHX_ &PL_blockhooks, newSViv(PTR2IV(hk)));
3071}
3072
76e3520e 3073STATIC OP *
cea2e8a9 3074S_newDEFSVOP(pTHX)
54b9620d 3075{
97aff369 3076 dVAR;
cc76b5cc 3077 const PADOFFSET offset = pad_findmy_pvs("$_", 0);
00b1698f 3078 if (offset == NOT_IN_PAD || PAD_COMPNAME_FLAGS_isOUR(offset)) {
59f00321
RGS
3079 return newSVREF(newGVOP(OP_GV, 0, PL_defgv));
3080 }
3081 else {
551405c4 3082 OP * const o = newOP(OP_PADSV, 0);
59f00321
RGS
3083 o->op_targ = offset;
3084 return o;
3085 }
54b9620d
MB
3086}
3087
a0d0e21e 3088void
864dbfa3 3089Perl_newPROG(pTHX_ OP *o)
a0d0e21e 3090{
97aff369 3091 dVAR;
7918f24d
NC
3092
3093 PERL_ARGS_ASSERT_NEWPROG;
3094
3280af22 3095 if (PL_in_eval) {
86a64801 3096 PERL_CONTEXT *cx;
63429d50 3097 I32 i;
b295d113
TH
3098 if (PL_eval_root)
3099 return;
faef0170
HS
3100 PL_eval_root = newUNOP(OP_LEAVEEVAL,
3101 ((PL_in_eval & EVAL_KEEPERR)
3102 ? OPf_SPECIAL : 0), o);
86a64801
GG
3103
3104 cx = &cxstack[cxstack_ix];
3105 assert(CxTYPE(cx) == CXt_EVAL);
3106
3107 if ((cx->blk_gimme & G_WANT) == G_VOID)
3108 scalarvoid(PL_eval_root);
3109 else if ((cx->blk_gimme & G_WANT) == G_ARRAY)
3110 list(PL_eval_root);
3111 else
3112 scalar(PL_eval_root);
3113
5983a79d 3114 PL_eval_start = op_linklist(PL_eval_root);
7934575e
GS
3115 PL_eval_root->op_private |= OPpREFCOUNTED;
3116 OpREFCNT_set(PL_eval_root, 1);
3280af22 3117 PL_eval_root->op_next = 0;
63429d50
FC
3118 i = PL_savestack_ix;
3119 SAVEFREEOP(o);
3120 ENTER;
a2efc822 3121 CALL_PEEP(PL_eval_start);
86a64801 3122 finalize_optree(PL_eval_root);
63429d50
FC
3123 LEAVE;
3124 PL_savestack_ix = i;
a0d0e21e
LW
3125 }
3126 else {
6be89cf9 3127 if (o->op_type == OP_STUB) {
22e660b4
NC
3128 /* This block is entered if nothing is compiled for the main
3129 program. This will be the case for an genuinely empty main
3130 program, or one which only has BEGIN blocks etc, so already
3131 run and freed.
3132
3133 Historically (5.000) the guard above was !o. However, commit
3134 f8a08f7b8bd67b28 (Jun 2001), integrated to blead as
3135 c71fccf11fde0068, changed perly.y so that newPROG() is now
3136 called with the output of block_end(), which returns a new
3137 OP_STUB for the case of an empty optree. ByteLoader (and
3138 maybe other things) also take this path, because they set up
3139 PL_main_start and PL_main_root directly, without generating an
3140 optree.
8b31d4e4
NC
3141
3142 If the parsing the main program aborts (due to parse errors,
3143 or due to BEGIN or similar calling exit), then newPROG()
3144 isn't even called, and hence this code path and its cleanups
3145 are skipped. This shouldn't make a make a difference:
3146 * a non-zero return from perl_parse is a failure, and
3147 perl_destruct() should be called immediately.
3148 * however, if exit(0) is called during the parse, then
3149 perl_parse() returns 0, and perl_run() is called. As
3150 PL_main_start will be NULL, perl_run() will return
3151 promptly, and the exit code will remain 0.
22e660b4
NC
3152 */
3153
6be89cf9
AE
3154 PL_comppad_name = 0;
3155 PL_compcv = 0;
d2c837a0 3156 S_op_destroy(aTHX_ o);
a0d0e21e 3157 return;
6be89cf9 3158 }
3ad73efd 3159 PL_main_root = op_scope(sawparens(scalarvoid(o)));
3280af22
NIS
3160 PL_curcop = &PL_compiling;
3161 PL_main_start = LINKLIST(PL_main_root);
7934575e
GS
3162 PL_main_root->op_private |= OPpREFCOUNTED;
3163 OpREFCNT_set(PL_main_root, 1);
3280af22 3164 PL_main_root->op_next = 0;
a2efc822 3165 CALL_PEEP(PL_main_start);
d164302a 3166 finalize_optree(PL_main_root);
8be227ab 3167 cv_forget_slab(PL_compcv);
3280af22 3168 PL_compcv = 0;
3841441e 3169
4fdae800 3170 /* Register with debugger */
84902520 3171 if (PERLDB_INTER) {
b96d8cd9 3172 CV * const cv = get_cvs("DB::postponed", 0);
3841441e
CS
3173 if (cv) {
3174 dSP;
924508f0 3175 PUSHMARK(SP);
ad64d0ec 3176 XPUSHs(MUTABLE_SV(CopFILEGV(&PL_compiling)));
3841441e 3177 PUTBACK;
ad64d0ec 3178 call_sv(MUTABLE_SV(cv), G_DISCARD);
3841441e
CS
3179 }
3180 }
79072805 3181 }
79072805
LW
3182}
3183
3184OP *
864dbfa3 3185Perl_localize(pTHX_ OP *o, I32 lex)
79072805 3186{
97aff369 3187 dVAR;
7918f24d
NC
3188
3189 PERL_ARGS_ASSERT_LOCALIZE;
3190
79072805 3191 if (o->op_flags & OPf_PARENS)
d2be0de5
YST
3192/* [perl #17376]: this appears to be premature, and results in code such as
3193 C< our(%x); > executing in list mode rather than void mode */
3194#if 0
79072805 3195 list(o);
d2be0de5 3196#else
6f207bd3 3197 NOOP;
d2be0de5 3198#endif
8990e307 3199 else {
f06b5848
DM
3200 if ( PL_parser->bufptr > PL_parser->oldbufptr
3201 && PL_parser->bufptr[-1] == ','
041457d9 3202 && ckWARN(WARN_PARENTHESIS))
64420d0d 3203 {
f06b5848 3204 char *s = PL_parser->bufptr;
bac662ee 3205 bool sigil = FALSE;
64420d0d 3206
8473848f 3207 /* some heuristics to detect a potential error */
bac662ee 3208 while (*s && (strchr(", \t\n", *s)))
64420d0d 3209 s++;
8473848f 3210
bac662ee
ST
3211 while (1) {
3212 if (*s && strchr("@$%*", *s) && *++s
0eb30aeb 3213 && (isWORDCHAR(*s) || UTF8_IS_CONTINUED(*s))) {
bac662ee
ST
3214 s++;
3215 sigil = TRUE;
0eb30aeb 3216 while (*s && (isWORDCHAR(*s) || UTF8_IS_CONTINUED(*s)))
bac662ee
ST
3217 s++;
3218 while (*s && (strchr(", \t\n", *s)))
3219 s++;
3220 }
3221 else
3222 break;
3223 }
3224 if (sigil && (*s == ';' || *s == '=')) {
3225 Perl_warner(aTHX_ packWARN(WARN_PARENTHESIS),
8473848f 3226 "Parentheses missing around \"%s\" list",
12bd6ede
DM
3227 lex
3228 ? (PL_parser->in_my == KEY_our
3229 ? "our"
3230 : PL_parser->in_my == KEY_state
3231 ? "state"
3232 : "my")
3233 : "local");
8473848f 3234 }
8990e307
LW
3235 }
3236 }
93a17b20 3237 if (lex)
eb64745e 3238 o = my(o);
93a17b20 3239 else
3ad73efd 3240 o = op_lvalue(o, OP_NULL); /* a bit kludgey */
12bd6ede
DM
3241 PL_parser->in_my = FALSE;
3242 PL_parser->in_my_stash = NULL;
eb64745e 3243 return o;
79072805
LW
3244}
3245
3246OP *
864dbfa3 3247Perl_jmaybe(pTHX_ OP *o)
79072805 3248{
7918f24d
NC
3249 PERL_ARGS_ASSERT_JMAYBE;
3250
79072805 3251 if (o->op_type == OP_LIST) {
fafc274c 3252 OP * const o2
d4c19fe8 3253 = newSVREF(newGVOP(OP_GV, 0, gv_fetchpvs(";", GV_ADD|GV_NOTQUAL, SVt_PV)));
2fcb4757 3254 o = convert(OP_JOIN, 0, op_prepend_elem(OP_LIST, o2, o));
79072805
LW
3255 }
3256 return o;
3257}
3258
985b9e54
GG
3259PERL_STATIC_INLINE OP *
3260S_op_std_init(pTHX_ OP *o)
3261{
3262 I32 type = o->op_type;
3263
3264 PERL_ARGS_ASSERT_OP_STD_INIT;
3265
3266 if (PL_opargs[type] & OA_RETSCALAR)
3267 scalar(o);
3268 if (PL_opargs[type] & OA_TARGET && !o->op_targ)
3269 o->op_targ = pad_alloc(type, SVs_PADTMP);
3270
3271 return o;
3272}
3273
3274PERL_STATIC_INLINE OP *
3275S_op_integerize(pTHX_ OP *o)
3276{
3277 I32 type = o->op_type;
3278
3279 PERL_ARGS_ASSERT_OP_INTEGERIZE;
3280
077da62f
FC
3281 /* integerize op. */
3282 if ((PL_opargs[type] & OA_OTHERINT) && (PL_hints & HINT_INTEGER))
985b9e54 3283 {
f5f19483 3284 dVAR;
985b9e54
GG
3285 o->op_ppaddr = PL_ppaddr[type = ++(o->op_type)];
3286 }
3287
3288 if (type == OP_NEGATE)
3289 /* XXX might want a ck_negate() for this */
3290 cUNOPo->op_first->op_private &= ~OPpCONST_STRICT;
3291
3292 return o;
3293}
3294
1f676739 3295static OP *
5aaab254 3296S_fold_constants(pTHX_ OP *o)
79072805 3297{
27da23d5 3298 dVAR;
eb578fdb 3299 OP * VOL curop;
eb8433b7 3300 OP *newop;
8ea43dc8 3301 VOL I32 type = o->op_type;
e3cbe32f 3302 SV * VOL sv = NULL;
b7f7fd0b
NC
3303 int ret = 0;
3304 I32 oldscope;
3305 OP *old_next;
5f2d9966
DM
3306 SV * const oldwarnhook = PL_warnhook;
3307 SV * const olddiehook = PL_diehook;
c427f4d2 3308 COP not_compiling;
b7f7fd0b 3309 dJMPENV;
79072805 3310
7918f24d
NC
3311 PERL_ARGS_ASSERT_FOLD_CONSTANTS;
3312
22c35a8c 3313 if (!(PL_opargs[type] & OA_FOLDCONST))
79072805
LW
3314 goto nope;
3315
de939608 3316 switch (type) {
de939608
CS
3317 case OP_UCFIRST:
3318 case OP_LCFIRST:
3319 case OP_UC:
3320 case OP_LC:
7ccde120 3321 case OP_FC:
69dcf70c
MB
3322 case OP_SLT:
3323 case OP_SGT:
3324 case OP_SLE:
3325 case OP_SGE:
3326 case OP_SCMP:
b3fd6149 3327 case OP_SPRINTF:
2de3dbcc 3328 /* XXX what about the numeric ops? */
82ad65bb 3329 if (IN_LOCALE_COMPILETIME)
de939608 3330 goto nope;
553e7bb0 3331 break;
dd9a6ccf
FC
3332 case OP_PACK:
3333 if (!cLISTOPo->op_first->op_sibling
3334 || cLISTOPo->op_first->op_sibling->op_type != OP_CONST)
3335 goto nope;
3336 {
3337 SV * const sv = cSVOPx_sv(cLISTOPo->op_first->op_sibling);
3338 if (!SvPOK(sv) || SvGMAGICAL(sv)) goto nope;
3339 {
3340 const char *s = SvPVX_const(sv);
3341 while (s < SvEND(sv)) {
3342 if (*s == 'p' || *s == 'P') goto nope;
3343 s++;
3344 }
3345 }
3346 }
3347 break;
baed7faa
FC
3348 case OP_REPEAT:
3349 if (o->op_private & OPpREPEAT_DOLIST) goto nope;
de939608
CS
3350 }
3351
13765c85 3352 if (PL_parser && PL_parser->error_count)
a0d0e21e
LW
3353 goto nope; /* Don't try to run w/ errors */
3354
79072805 3355 for (curop = LINKLIST(o); curop != o; curop = LINKLIST(curop)) {
1496a290
AL
3356 const OPCODE type = curop->op_type;
3357 if ((type != OP_CONST || (curop->op_private & OPpCONST_BARE)) &&
3358 type != OP_LIST &&
3359 type != OP_SCALAR &&
3360 type != OP_NULL &&
3361 type != OP_PUSHMARK)
7a52d87a 3362 {
79072805
LW
3363 goto nope;
3364 }
3365 }
3366
3367 curop = LINKLIST(o);
b7f7fd0b 3368 old_next = o->op_next;
79072805 3369 o->op_next = 0;
533c011a 3370 PL_op = curop;
b7f7fd0b
NC
3371
3372 oldscope = PL_scopestack_ix;
edb2152a 3373 create_eval_scope(G_FAKINGEVAL);
b7f7fd0b 3374
c427f4d2
NC
3375 /* Verify that we don't need to save it: */
3376 assert(PL_curcop == &PL_compiling);
3377 StructCopy(&PL_compiling, &not_compiling, COP);
3378 PL_curcop = &not_compiling;
3379 /* The above ensures that we run with all the correct hints of the
3380 currently compiling COP, but that IN_PERL_RUNTIME is not true. */
3381 assert(IN_PERL_RUNTIME);
5f2d9966
DM
3382 PL_warnhook = PERL_WARNHOOK_FATAL;
3383 PL_diehook = NULL;
b7f7fd0b
NC
3384 JMPENV_PUSH(ret);
3385
3386 switch (ret) {
3387 case 0:
3388 CALLRUNOPS(aTHX);
3389 sv = *(PL_stack_sp--);
523a0f0c
NC
3390 if (o->op_targ && sv == PAD_SV(o->op_targ)) { /* grab pad temp? */
3391#ifdef PERL_MAD
3392 /* Can't simply swipe the SV from the pad, because that relies on
3393 the op being freed "real soon now". Under MAD, this doesn't
3394 happen (see the #ifdef below). */
3395 sv = newSVsv(sv);
3396#else
b7f7fd0b 3397 pad_swipe(o->op_targ, FALSE);
523a0f0c
NC
3398#endif
3399 }
b7f7fd0b
NC
3400 else if (SvTEMP(sv)) { /* grab mortal temp? */
3401 SvREFCNT_inc_simple_void(sv);
3402 SvTEMP_off(sv);
3403 }
ba610af8 3404 else { assert(SvIMMORTAL(sv)); }
b7f7fd0b
NC
3405 break;
3406 case 3:
3407 /* Something tried to die. Abandon constant folding. */
3408 /* Pretend the error never happened. */
ab69dbc2 3409 CLEAR_ERRSV();
b7f7fd0b
NC
3410 o->op_next = old_next;
3411 break;
3412 default:
3413 JMPENV_POP;
5f2d9966
DM
3414 /* Don't expect 1 (setjmp failed) or 2 (something called my_exit) */
3415 PL_warnhook = oldwarnhook;
3416 PL_diehook = olddiehook;
3417 /* XXX note that this croak may fail as we've already blown away
3418 * the stack - eg any nested evals */
b7f7fd0b
NC
3419 Perl_croak(aTHX_ "panic: fold_constants JMPENV_PUSH returned %d", ret);
3420 }
b7f7fd0b 3421 JMPENV_POP;
5f2d9966
DM
3422 PL_warnhook = oldwarnhook;
3423 PL_diehook = olddiehook;
c427f4d2 3424 PL_curcop = &PL_compiling;
edb2152a
NC
3425
3426 if (PL_scopestack_ix > oldscope)
3427 delete_eval_scope();
eb8433b7 3428
b7f7fd0b
NC
3429 if (ret)
3430 goto nope;
3431
eb8433b7 3432#ifndef PERL_MAD
79072805 3433 op_free(o);
eb8433b7 3434#endif
de5e01c2 3435 assert(sv);
07a05c08
FC
3436 if (type == OP_STRINGIFY) SvPADTMP_off(sv);
3437 else if (!SvIMMORTAL(sv)) SvPADTMP_on(sv);
79072805 3438 if (type == OP_RV2GV)
159b6efe 3439 newop = newGVOP(OP_GV, 0, MUTABLE_GV(sv));
eb8433b7 3440 else
3513c740 3441 {
cc2ebcd7 3442 newop = newSVOP(OP_CONST, OPpCONST_FOLDED<<8, MUTABLE_SV(sv));
3513c740
NT
3443 newop->op_folded = 1;
3444 }
eb8433b7
NC
3445 op_getmad(o,newop,'f');
3446 return newop;
aeea060c 3447
b7f7fd0b 3448 nope:
79072805
LW
3449 return o;
3450}
3451
1f676739 3452static OP *
5aaab254 3453S_gen_constant_list(pTHX_ OP *o)
79072805 3454{
27da23d5 3455 dVAR;
eb578fdb 3456 OP *curop;
e8eb279c 3457 const SSize_t oldtmps_floor = PL_tmps_floor;
5608dcc6
FC
3458 SV **svp;
3459 AV *av;
79072805 3460
a0d0e21e 3461 list(o);
13765c85 3462 if (PL_parser && PL_parser->error_count)
a0d0e21e
LW
3463 return o; /* Don't attempt to run with errors */
3464
533c011a 3465 PL_op = curop = LINKLIST(o);
a0d0e21e 3466 o->op_next = 0;
a2efc822 3467 CALL_PEEP(curop);
897d3989 3468 Perl_pp_pushmark(aTHX);
cea2e8a9 3469 CALLRUNOPS(aTHX);
533c011a 3470 PL_op = curop;
78c72037
NC
3471 assert (!(curop->op_flags & OPf_SPECIAL));
3472 assert(curop->op_type == OP_RANGE);
897d3989 3473 Perl_pp_anonlist(aTHX);
3280af22 3474 PL_tmps_floor = oldtmps_floor;
79072805
LW
3475
3476 o->op_type = OP_RV2AV;
22c35a8c 3477 o->op_ppaddr = PL_ppaddr[OP_RV2AV];
fb53bbb2
SG
3478 o->op_flags &= ~OPf_REF; /* treat \(1..2) like an ordinary list */
3479 o->op_flags |= OPf_PARENS; /* and flatten \(1..2,3) */
1a0a2ba9 3480 o->op_opt = 0; /* needs to be revisited in rpeep() */
79072805 3481 curop = ((UNOP*)o)->op_first;
5608dcc6
FC
3482 av = (AV *)SvREFCNT_inc_NN(*PL_stack_sp--);
3483 ((UNOP*)o)->op_first = newSVOP(OP_CONST, 0, (SV *)av);
3484 if (AvFILLp(av) != -1)
3485 for (svp = AvARRAY(av) + AvFILLp(av); svp >= AvARRAY(av); --svp)
3486 SvPADTMP_on(*svp);
eb8433b7
NC
3487#ifdef PERL_MAD
3488 op_getmad(curop,o,'O');
3489#else
79072805 3490 op_free(curop);
eb8433b7 3491#endif
5983a79d 3492 LINKLIST(o);
79072805
LW
3493 return list(o);
3494}
3495
3496OP *
864dbfa3 3497Perl_convert(pTHX_ I32 type, I32 flags, OP *o)
79072805 3498{
27da23d5 3499 dVAR;
d67594ff 3500 if (type < 0) type = -type, flags |= OPf_SPECIAL;
11343788 3501 if (!o || o->op_type != OP_LIST)
5f66b61c 3502 o = newLISTOP(OP_LIST, 0, o, NULL);
748a9306 3503 else
5dc0d613 3504 o->op_flags &= ~OPf_WANT;
79072805 3505
22c35a8c 3506 if (!(PL_opargs[type] & OA_MARK))
93c66552 3507 op_null(cLISTOPo->op_first);
bf0571fd
FC
3508 else {
3509 OP * const kid2 = cLISTOPo->op_first->op_sibling;
3510 if (kid2 && kid2->op_type == OP_COREARGS) {
3511 op_null(cLISTOPo->op_first);
3512 kid2->op_private |= OPpCOREARGS_PUSHMARK;
3513 }
3514 }
8990e307 3515
eb160463 3516 o->op_type = (OPCODE)type;
22c35a8c 3517 o->op_ppaddr = PL_ppaddr[type];
11343788 3518 o->op_flags |= flags;
79072805 3519
11343788 3520 o = CHECKOP(type, o);
fe2774ed 3521 if (o->op_type != (unsigned)type)
11343788 3522 return o;
79072805 3523
985b9e54 3524 return fold_constants(op_integerize(op_std_init(o)));
79072805
LW
3525}
3526
2fcb4757
Z
3527/*
3528=head1 Optree Manipulation Functions
3529*/
3530
79072805
LW
3531/* List constructors */
3532
2fcb4757
Z
3533/*
3534=for apidoc Am|OP *|op_append_elem|I32 optype|OP *first|OP *last
3535
3536Append an item to the list of ops contained directly within a list-type
3537op, returning the lengthened list. I<first> is the list-type op,
3538and I<last> is the op to append to the list. I<optype> specifies the
3539intended opcode for the list. If I<first> is not already a list of the
3540right type, it will be upgraded into one. If either I<first> or I<last>
3541is null, the other is returned unchanged.
3542
3543=cut
3544*/
3545
79072805 3546OP *
2fcb4757 3547Perl_op_append_elem(pTHX_ I32 type, OP *first, OP *last)
79072805
LW
3548{
3549 if (!first)
3550 return last;
8990e307
LW
3551
3552 if (!last)
79072805 3553 return first;
8990e307 3554
fe2774ed 3555 if (first->op_type != (unsigned)type
155aba94
GS
3556 || (type == OP_LIST && (first->op_flags & OPf_PARENS)))
3557 {
3558 return newLISTOP(type, 0, first, last);
3559 }
79072805 3560
a0d0e21e
LW
3561 if (first->op_flags & OPf_KIDS)
3562 ((LISTOP*)first)->op_last->op_sibling = last;
3563 else {
3564 first->op_flags |= OPf_KIDS;
3565 ((LISTOP*)first)->op_first = last;
3566 }
3567 ((LISTOP*)first)->op_last = last;
a0d0e21e 3568 return first;
79072805
LW
3569}
3570
2fcb4757
Z
3571/*
3572=for apidoc Am|OP *|op_append_list|I32 optype|OP *first|OP *last
3573
3574Concatenate the lists of ops contained directly within two list-type ops,
3575returning the combined list. I<first> and I<last> are the list-type ops
3576to concatenate. I<optype> specifies the intended opcode for the list.
3577If either I<first> or I<last> is not already a list of the right type,
3578it will be upgraded into one. If either I<first> or I<last> is null,
3579the other is returned unchanged.
3580
3581=cut
3582*/
3583
79072805 3584OP *
2fcb4757 3585Perl_op_append_list(pTHX_ I32 type, OP *first, OP *last)
79072805
LW
3586{
3587 if (!first)
2fcb4757 3588 return last;
8990e307
LW
3589
3590 if (!last)
2fcb4757 3591 return first;
8990e307 3592
fe2774ed 3593 if (first->op_type != (unsigned)type)
2fcb4757 3594 return op_prepend_elem(type, first, last);
8990e307 3595
fe2774ed 3596 if (last->op_type != (unsigned)type)
2fcb4757 3597 return op_append_elem(type, first, last);
79072805 3598
2fcb4757
Z
3599 ((LISTOP*)first)->op_last->op_sibling = ((LISTOP*)last)->op_first;
3600 ((LISTOP*)first)->op_last = ((LISTOP*)last)->op_last;
117dada2 3601 first->op_flags |= (last->op_flags & OPf_KIDS);
1c846c1f 3602
eb8433b7 3603#ifdef PERL_MAD
2fcb4757
Z
3604 if (((LISTOP*)last)->op_first && first->op_madprop) {
3605 MADPROP *mp = ((LISTOP*)last)->op_first->op_madprop;
eb8433b7
NC
3606 if (mp) {
3607 while (mp->mad_next)
3608 mp = mp->mad_next;
3609 mp->mad_next = first->op_madprop;
3610 }
3611 else {
2fcb4757 3612 ((LISTOP*)last)->op_first->op_madprop = first->op_madprop;
eb8433b7
NC
3613 }
3614 }
3615 first->op_madprop = last->op_madprop;
3616 last->op_madprop = 0;
3617#endif
3618
2fcb4757 3619 S_op_destroy(aTHX_ last);
238a4c30 3620
2fcb4757 3621 return first;
79072805
LW
3622}
3623
2fcb4757
Z
3624/*
3625=for apidoc Am|OP *|op_prepend_elem|I32 optype|OP *first|OP *last
3626
3627Prepend an item to the list of ops contained directly within a list-type
3628op, returning the lengthened list. I<first> is the op to prepend to the
3629list, and I<last> is the list-type op. I<optype> specifies the intended
3630opcode for the list. If I<last> is not already a list of the right type,
3631it will be upgraded into one. If either I<first> or I<last> is null,
3632</