File Coverage

File:autovivification.xs
Coverage:98.2%

linestmtbrancondsubpodtimecode
1/* This file is part of the autovivification Perl module.
2 * See http://search.cpan.org/dist/autovivification/ */
3
4#define PERL_NO_GET_CONTEXT
5#include "EXTERN.h"
6#include "perl.h"
7#include "XSUB.h"
8
9#define __PACKAGE__ "autovivification"
10#define __PACKAGE_LEN__ (sizeof(__PACKAGE__)-1)
11
12/* --- Compatibility wrappers ---------------------------------------------- */
13
14#ifndef HvNAME_get
15# define HvNAME_get(H) HvNAME(H)
16#endif
17
18#ifndef HvNAMELEN_get
19# define HvNAMELEN_get(H) strlen(HvNAME_get(H))
20#endif
21
22#define A_HAS_PERL(R, V, S) (PERL_REVISION > (R) || (PERL_REVISION == (R) && (PERL_VERSION > (V) || (PERL_VERSION == (V) && (PERL_SUBVERSION >= (S))))))
23
24#ifndef A_WORKAROUND_REQUIRE_PROPAGATION
25# define A_WORKAROUND_REQUIRE_PROPAGATION !A_HAS_PERL(5, 10, 1)
26#endif
27
28#ifndef A_HAS_RPEEP
29# define A_HAS_RPEEP A_HAS_PERL(5, 13, 5)
30#endif
31
32/* ... Thread safety and multiplicity ...................................... */
33
34/* Always safe when the workaround isn't needed */
35#if !A_WORKAROUND_REQUIRE_PROPAGATION
36# undef A_FORKSAFE
37# define A_FORKSAFE 1
38/* Otherwise, safe unless Makefile.PL says it's Win32 */
39#elif !defined(A_FORKSAFE)
40# define A_FORKSAFE 1
41#endif
42
43#ifndef A_MULTIPLICITY
44# if defined(MULTIPLICITY) || defined(PERL_IMPLICIT_CONTEXT)
45# define A_MULTIPLICITY 1
46# else
47# define A_MULTIPLICITY 0
48# endif
49#endif
50
51#ifndef tTHX
52# define tTHX PerlInterpreter*
53#endif
54
55#if A_MULTIPLICITY && defined(USE_ITHREADS) && defined(dMY_CXT) && defined(MY_CXT) && defined(START_MY_CXT) && defined(MY_CXT_INIT) && (defined(MY_CXT_CLONE) || defined(dMY_CXT_SV))
56# define A_THREADSAFE 1
57# ifndef MY_CXT_CLONE
58# define MY_CXT_CLONE \
59    dMY_CXT_SV; \
60    my_cxt_t *my_cxtp = (my_cxt_t*)SvPVX(newSV(sizeof(my_cxt_t)-1)); \
61    Copy(INT2PTR(my_cxt_t*, SvUV(my_cxt_sv)), my_cxtp, 1, my_cxt_t); \
62    sv_setuv(my_cxt_sv, PTR2UV(my_cxtp))
63# endif
64#else
65# define A_THREADSAFE 0
66# undef dMY_CXT
67# define dMY_CXT dNOOP
68# undef MY_CXT
69# define MY_CXT a_globaldata
70# undef START_MY_CXT
71# define START_MY_CXT STATIC my_cxt_t MY_CXT;
72# undef MY_CXT_INIT
73# define MY_CXT_INIT NOOP
74# undef MY_CXT_CLONE
75# define MY_CXT_CLONE NOOP
76#endif
77
78/* --- Helpers ------------------------------------------------------------- */
79
80/* ... Thread-safe hints ................................................... */
81
82#if A_WORKAROUND_REQUIRE_PROPAGATION
83
84typedef struct {
85 U32 bits;
86 IV require_tag;
87} a_hint_t;
88
89#define A_HINT_FREE(H) PerlMemShared_free(H)
90
91#if A_THREADSAFE
92
93#define PTABLE_NAME ptable_hints
94#define PTABLE_VAL_FREE(V) A_HINT_FREE(V)
95
96#define pPTBL pTHX
97#define pPTBL_ pTHX_
98#define aPTBL aTHX
99#define aPTBL_ aTHX_
100
101#include "ptable.h"
102
103#define ptable_hints_store(T, K, V) ptable_hints_store(aTHX_ (T), (K), (V))
104#define ptable_hints_free(T) ptable_hints_free(aTHX_ (T))
105
106#endif /* A_THREADSAFE */
107
108#endif /* A_WORKAROUND_REQUIRE_PROPAGATION */
109
110#define PTABLE_NAME ptable_seen
111#define PTABLE_VAL_FREE(V) NOOP
112
113#include "ptable.h"
114
115/* PerlMemShared_free() needs the [ap]PTBLMS_? default values */
116#define ptable_seen_store(T, K, V) ptable_seen_store(aPTBLMS_ (T), (K), (V))
117#define ptable_seen_clear(T) ptable_seen_clear(aPTBLMS_ (T))
118#define ptable_seen_free(T) ptable_seen_free(aPTBLMS_ (T))
119
120#define MY_CXT_KEY __PACKAGE__ "::_guts" XS_VERSION
121
122typedef struct {
123#if A_THREADSAFE && A_WORKAROUND_REQUIRE_PROPAGATION
124 ptable *tbl; /* It really is a ptable_hints */
125 tTHX owner;
126#endif /* A_THREADSAFE && A_WORKAROUND_REQUIRE_PROPAGATION */
127 ptable *seen; /* It really is a ptable_seen */
128} my_cxt_t;
129
130START_MY_CXT
131
132#if A_THREADSAFE
133
134#if A_WORKAROUND_REQUIRE_PROPAGATION
135
136typedef struct {
137 ptable *tbl;
138#if A_HAS_PERL(5, 13, 2)
139 CLONE_PARAMS *params;
140#else
141 CLONE_PARAMS params;
142#endif
143} a_ptable_clone_ud;
144
145#if A_HAS_PERL(5, 13, 2)
146# define a_ptable_clone_ud_init(U, T, O) \
147   (U).tbl = (T); \
148   (U).params = Perl_clone_params_new((O), aTHX)
149# define a_ptable_clone_ud_deinit(U) Perl_clone_params_del((U).params)
150# define a_dup_inc(S, U) SvREFCNT_inc(sv_dup((S), (U)->params))
151#else
152# define a_ptable_clone_ud_init(U, T, O) \
153   (U).tbl = (T); \
154   (U).params.stashes = newAV(); \
155   (U).params.flags = 0; \
156   (U).params.proto_perl = (O)
157# define a_ptable_clone_ud_deinit(U) SvREFCNT_dec((U).params.stashes)
158# define a_dup_inc(S, U) SvREFCNT_inc(sv_dup((S), &((U)->params)))
159#endif
160
161STATIC void a_ptable_clone(pTHX_ ptable_ent *ent, void *ud_) {
162 a_ptable_clone_ud *ud = ud_;
163 a_hint_t *h1 = ent->val;
164 a_hint_t *h2;
165
166 h2 = PerlMemShared_malloc(sizeof *h2);
167 h2->bits = h1->bits;
168 h2->require_tag = PTR2IV(a_dup_inc(INT2PTR(SV *, h1->require_tag), ud));
169
170 ptable_hints_store(ud->tbl, ent->key, h2);
171}
172
173#endif /* A_WORKAROUND_REQUIRE_PROPAGATION */
174
175#include "reap.h"
176
177STATIC void a_thread_cleanup(pTHX_ void *ud) {
178 dMY_CXT;
179
180#if A_WORKAROUND_REQUIRE_PROPAGATION
181 ptable_hints_free(MY_CXT.tbl);
182#endif /* A_WORKAROUND_REQUIRE_PROPAGATION */
183 ptable_seen_free(MY_CXT.seen);
184}
185
186#endif /* A_THREADSAFE */
187
188#if A_WORKAROUND_REQUIRE_PROPAGATION
189
190STATIC IV a_require_tag(pTHX) {
191#define a_require_tag() a_require_tag(aTHX)
192 const CV *cv, *outside;
193
194 cv = PL_compcv;
195
196 if (!cv) {
197  /* If for some reason the pragma is operational at run-time, try to discover
198   * the current cv in use. */
199  const PERL_SI *si;
200
201  for (si = PL_curstackinfo; si; si = si->si_prev) {
202   I32 cxix;
203
204   for (cxix = si->si_cxix; cxix >= 0; --cxix) {
205    const PERL_CONTEXT *cx = si->si_cxstack + cxix;
206
207    switch (CxTYPE(cx)) {
208     case CXt_SUB:
209     case CXt_FORMAT:
210      /* The propagation workaround is only needed up to 5.10.0 and at that
211       * time format and sub contexts were still identical. And even later the
212       * cv members offsets should have been kept the same. */
213      cv = cx->blk_sub.cv;
214      goto get_enclosing_cv;
215     case CXt_EVAL:
216      cv = cx->blk_eval.cv;
217      goto get_enclosing_cv;
218     default:
219      break;
220    }
221   }
222  }
223
224  cv = PL_main_cv;
225 }
226
227get_enclosing_cv:
228 for (outside = CvOUTSIDE(cv); outside; outside = CvOUTSIDE(cv))
229  cv = outside;
230
231 return PTR2IV(cv);
232}
233
234STATIC SV *a_tag(pTHX_ UV bits) {
235#define a_tag(B) a_tag(aTHX_ (B))
236 a_hint_t *h;
237
238 h = PerlMemShared_malloc(sizeof *h);
239 h->bits = bits;
240 h->require_tag = a_require_tag();
241
242#if A_THREADSAFE
243 {
244  dMY_CXT;
245  /* We only need for the key to be an unique tag for looking up the value later
246   * Allocated memory provides convenient unique identifiers, so that's why we
247   * use the hint as the key itself. */
248  ptable_hints_store(MY_CXT.tbl, h, h);
249 }
250#endif /* A_THREADSAFE */
251
252 return newSViv(PTR2IV(h));
253}
254
255STATIC UV a_detag(pTHX_ const SV *hint) {
256#define a_detag(H) a_detag(aTHX_ (H))
257 a_hint_t *h;
258
259 if (!(hint && SvIOK(hint)))
260  return 0;
261
262 h = INT2PTR(a_hint_t *, SvIVX(hint));
263#if A_THREADSAFE
264 {
265  dMY_CXT;
266  h = ptable_fetch(MY_CXT.tbl, h);
267 }
268#endif /* A_THREADSAFE */
269
270 if (a_require_tag() != h->require_tag)
271  return 0;
272
273 return h->bits;
274}
275
276#else /* A_WORKAROUND_REQUIRE_PROPAGATION */
277
278#define a_tag(B) newSVuv(B)
279/* PVs fetched from the hints chain have their SvLEN set to zero, so get the UV
280 * from a copy. */
281#define a_detag(H) \
282 ((H) \
283  ? (SvIOK(H) \
284     ? SvUVX(H) \
285     : (SvPOK(H) \
286        ? sv_2uv(SvLEN(H) ? (H) : sv_mortalcopy(H)) \
287        : 0 \
288       ) \
289     ) \
290  : 0)
291
292#endif /* !A_WORKAROUND_REQUIRE_PROPAGATION */
293
294/* Used both for hints and op flags */
295#define A_HINT_STRICT 1
296#define A_HINT_WARN 2
297#define A_HINT_FETCH 4
298#define A_HINT_STORE 8
299#define A_HINT_EXISTS 16
300#define A_HINT_DELETE 32
301#define A_HINT_NOTIFY (A_HINT_STRICT|A_HINT_WARN)
302#define A_HINT_DO (A_HINT_FETCH|A_HINT_STORE|A_HINT_EXISTS|A_HINT_DELETE)
303#define A_HINT_MASK (A_HINT_NOTIFY|A_HINT_DO)
304
305/* Only used in op flags */
306#define A_HINT_ROOT 64
307#define A_HINT_DEREF 128
308
309STATIC U32 a_hash = 0;
310
311
291184
STATIC UV a_hint(pTHX) {
312#define a_hint() a_hint(aTHX)
313 SV *hint;
314#ifdef cop_hints_fetch_pvn
315
291184
 hint = cop_hints_fetch_pvn(PL_curcop, __PACKAGE__, __PACKAGE_LEN__, a_hash, 0);
316#elif A_HAS_PERL(5, 9, 5)
317 hint = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
318                                       NULL,
319                                       __PACKAGE__, __PACKAGE_LEN__,
320                                       0,
321                                       a_hash);
322#else
323 SV **val = hv_fetch(GvHV(PL_hintgv), __PACKAGE__, __PACKAGE_LEN__, a_hash);
324 if (!val)
325  return 0;
326 hint = *val;
327#endif
328
291184
 return a_detag(hint);
329}
330
331/* ... op => info map ...................................................... */
332
333typedef struct {
334 OP *(*old_pp)(pTHX);
335 UV flags;
336 void *next;
337} a_op_info;
338
339#define PTABLE_NAME ptable_map
340#define PTABLE_VAL_FREE(V) PerlMemShared_free(V)
341
342#include "ptable.h"
343
344/* PerlMemShared_free() needs the [ap]PTBLMS_? default values */
345#define ptable_map_store(T, K, V) ptable_map_store(aPTBLMS_ (T), (K), (V))
346#define ptable_map_delete(T, K) ptable_map_delete(aPTBLMS_ (T), (K))
347
348STATIC ptable *a_op_map = NULL;
349
350#ifdef USE_ITHREADS
351
352#define dA_MAP_THX a_op_info a_op_map_tmp_oi
353
354STATIC perl_mutex a_op_map_mutex;
355
356#define A_LOCK(M) MUTEX_LOCK(M)
357#define A_UNLOCK(M) MUTEX_UNLOCK(M)
358
359STATIC const a_op_info *a_map_fetch(const OP *o, a_op_info *oi) {
360 const a_op_info *val;
361
362 A_LOCK(&a_op_map_mutex);
363
364 val = ptable_fetch(a_op_map, o);
365 if (val) {
366  *oi = *val;
367  val = oi;
368 }
369
370 A_UNLOCK(&a_op_map_mutex);
371
372 return val;
373}
374
375#define a_map_fetch(O) a_map_fetch((O), &a_op_map_tmp_oi)
376
377#else /* USE_ITHREADS */
378
379#define dA_MAP_THX dNOOP
380
381#define A_LOCK(M) NOOP
382#define A_UNLOCK(M) NOOP
383
384#define a_map_fetch(O) ptable_fetch(a_op_map, (O))
385
386#endif /* !USE_ITHREADS */
387
388
39219
STATIC const a_op_info *a_map_store_locked(pPTBLMS_ const OP *o, OP *(*old_pp)(pTHX), void *next, UV flags) {
389#define a_map_store_locked(O, PP, N, F) a_map_store_locked(aPTBLMS_ (O), (PP), (N), (F))
390 a_op_info *oi;
391
392
39219
 if (!(oi = ptable_fetch(a_op_map, o))) {
393
35778
  oi = PerlMemShared_malloc(sizeof *oi);
394
35778
  ptable_map_store(a_op_map, o, oi);
395 }
396
397
39219
 oi->old_pp = old_pp;
398
39219
 oi->next = next;
399
39219
 oi->flags = flags;
400
401
39219
 return oi;
402}
403
404
3003
STATIC void a_map_store(pPTBLMS_ const OP *o, OP *(*old_pp)(pTHX), void *next, UV flags) {
405#define a_map_store(O, PP, N, F) a_map_store(aPTBLMS_ (O), (PP), (N), (F))
406 A_LOCK(&a_op_map_mutex);
407
408
3003
 a_map_store_locked(o, old_pp, next, flags);
409
410 A_UNLOCK(&a_op_map_mutex);
411
3003
}
412
413
252160
STATIC void a_map_delete(pTHX_ const OP *o) {
414#define a_map_delete(O) a_map_delete(aTHX_ (O))
415 A_LOCK(&a_op_map_mutex);
416
417
252160
 ptable_map_delete(a_op_map, o);
418
419 A_UNLOCK(&a_op_map_mutex);
420
252160
}
421
422
49750
STATIC const OP *a_map_descend(const OP *o) {
423
49750
 switch (PL_opargs[o->op_type] & OA_CLASS_MASK) {
424  case OA_BASEOP:
425  case OA_UNOP:
426  case OA_BINOP:
427  case OA_BASEOP_OR_UNOP:
428
48642
   return cUNOPo->op_first;
429  case OA_LIST:
430  case OA_LISTOP:
431
1108
   return cLISTOPo->op_last;
432 }
433
434
49750
 return NULL;
435}
436
437
36216
STATIC void a_map_store_root(pPTBLMS_ const OP *root, OP *(*old_pp)(pTHX), UV flags) {
438#define a_map_store_root(R, PP, F) a_map_store_root(aPTBLMS_ (R), (PP), (F))
439 const a_op_info *roi;
440 a_op_info *oi;
441
36216
 const OP *o = root;
442
443 A_LOCK(&a_op_map_mutex);
444
445
36216
 roi = a_map_store_locked(o, old_pp, (OP *) root, flags | A_HINT_ROOT);
446
447
68431
 while (o->op_flags & OPf_KIDS) {
448
32215
  o = a_map_descend(o);
449
32215
  if (!o)
450
0
   break;
451
32215
  if ((oi = ptable_fetch(a_op_map, o))) {
452
23272
   oi->flags &= ~A_HINT_ROOT;
453
23272
   oi->next = (a_op_info *) roi;
454
23272
   break;
455  }
456 }
457
458 A_UNLOCK(&a_op_map_mutex);
459
460 return;
461}
462
463
4079
STATIC void a_map_update_flags_topdown(const OP *root, UV flags) {
464 a_op_info *oi;
465
4079
 const OP *o = root;
466
467 A_LOCK(&a_op_map_mutex);
468
469
4079
 flags &= ~A_HINT_ROOT;
470
471 do {
472
21614
  if ((oi = ptable_fetch(a_op_map, o)))
473
12740
   oi->flags = (oi->flags & A_HINT_ROOT) | flags;
474
21614
  if (!(o->op_flags & OPf_KIDS))
475
4079
   break;
476
17535
  o = a_map_descend(o);
477
21614
 } while (o);
478
479 A_UNLOCK(&a_op_map_mutex);
480
481 return;
482}
483
484#define a_map_cancel(R) a_map_update_flags_topdown((R), 0)
485
486
4082
STATIC void a_map_update_flags_bottomup(const OP *o, UV flags, UV rflags) {
487 a_op_info *oi;
488
489 A_LOCK(&a_op_map_mutex);
490
491
4082
 flags &= ~A_HINT_ROOT;
492
4082
 rflags |= A_HINT_ROOT;
493
494
4082
 oi = ptable_fetch(a_op_map, o);
495
12144
 while (!(oi->flags & A_HINT_ROOT)) {
496
8062
  oi->flags = flags;
497
8062
  oi = oi->next;
498 }
499
4082
 oi->flags = rflags;
500
501 A_UNLOCK(&a_op_map_mutex);
502
503 return;
504}
505
506/* ... Decide whether this expression should be autovivified or not ........ */
507
508
4082
STATIC UV a_map_resolve(const OP *o, const a_op_info *oi) {
509
4082
 UV flags = 0, rflags;
510 const OP *root;
511
4082
 const a_op_info *roi = oi;
512
513
12144
 while (!(roi->flags & A_HINT_ROOT))
514
8062
  roi = roi->next;
515
4082
 if (!roi)
516
0
  goto cancel;
517
518
4082
 rflags = roi->flags & ~A_HINT_ROOT;
519
4082
 if (!rflags)
520
0
  goto cancel;
521
522
4082
 root = roi->next;
523
4082
 if (root->op_flags & OPf_MOD) {
524
2348
  if (rflags & A_HINT_STORE)
525
540
   flags = (A_HINT_STORE|A_HINT_DEREF);
526
1734
 } else if (rflags & A_HINT_FETCH)
527
600
   flags = (A_HINT_FETCH|A_HINT_DEREF);
528
529
4082
 if (!flags) {
530cancel:
531
2942
  a_map_update_flags_bottomup(o, 0, 0);
532
2942
  return 0;
533 }
534
535
1140
 flags |= (rflags & A_HINT_NOTIFY);
536
1140
 a_map_update_flags_bottomup(o, flags, 0);
537
538
4082
 return oi->flags & A_HINT_ROOT ? 0 : flags;
539}
540
541/* ... Inspired from pp_defined() .......................................... */
542
543
11624
STATIC int a_undef(pTHX_ SV *sv) {
544#define a_undef(S) a_undef(aTHX_ (S))
545
11624
 switch (SvTYPE(sv)) {
546  case SVt_NULL:
547
5671
   return 1;
548  case SVt_PVAV:
549
1448
   if (AvMAX(sv) >= 0 || SvGMAGICAL(sv)
550
1124
                      || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
551
324
    return 0;
552
1124
   break;
553  case SVt_PVHV:
554
217
   if (HvARRAY(sv) || SvGMAGICAL(sv)
555
36
                   || (SvRMAGICAL(sv) && mg_find(sv, PERL_MAGIC_tied)))
556
181
    return 0;
557
36
   break;
558  default:
559
4288
   SvGETMAGIC(sv);
560
4288
   if (SvOK(sv))
561
3148
    return 0;
562 }
563
564
11624
 return 1;
565}
566
567/* --- PP functions -------------------------------------------------------- */
568
569/* Be aware that we restore PL_op->op_ppaddr from the pointer table old_pp
570 * value, another extension might have saved our pp replacement as the ppaddr
571 * for this op, so this doesn't ensure that our function will never be called
572 * again. That's why we don't remove the op info from our map, so that it can
573 * still run correctly if required. */
574
575/* ... pp_rv2av ............................................................ */
576
577
4040
STATIC OP *a_pp_rv2av(pTHX) {
578 dA_MAP_THX;
579 const a_op_info *oi;
580
4040
 dSP;
581
582
4040
 oi = a_map_fetch(PL_op);
583
584
4040
 if (oi->flags & A_HINT_DEREF) {
585
4040
  if (a_undef(TOPs)) {
586   /* We always need to push an empty array to fool the pp_aelem() that comes
587    * later. */
588   SV *av;
589
2759
   POPs;
590
2759
   av = sv_2mortal((SV *) newAV());
591
2759
   PUSHs(av);
592
2759
   RETURN;
593  }
594 }
595
596
4040
 return oi->old_pp(aTHX);
597}
598
599/* ... pp_rv2hv ............................................................ */
600
601
3174
STATIC OP *a_pp_rv2hv_simple(pTHX) {
602 dA_MAP_THX;
603 const a_op_info *oi;
604
3174
 dSP;
605
606
3174
 oi = a_map_fetch(PL_op);
607
608
3174
 if (oi->flags & A_HINT_DEREF) {
609
3174
  if (a_undef(TOPs))
610
2141
   RETURN;
611 }
612
613
3174
 return oi->old_pp(aTHX);
614}
615
616
436
STATIC OP *a_pp_rv2hv(pTHX) {
617 dA_MAP_THX;
618 const a_op_info *oi;
619
436
 dSP;
620
621
436
 oi = a_map_fetch(PL_op);
622
623
436
 if (oi->flags & A_HINT_DEREF) {
624
436
  if (a_undef(TOPs)) {
625   SV *hv;
626
412
   POPs;
627
412
   hv = sv_2mortal((SV *) newHV());
628
412
   PUSHs(hv);
629
412
   RETURN;
630  }
631 }
632
633
436
 return oi->old_pp(aTHX);
634}
635
636/* ... pp_deref (aelem,helem,rv2sv,padsv) .................................. */
637
638
8726
STATIC OP *a_pp_deref(pTHX) {
639 dA_MAP_THX;
640 const a_op_info *oi;
641 UV flags;
642
8726
 dSP;
643
644
8726
 oi = a_map_fetch(PL_op);
645
646
8726
 flags = oi->flags;
647
8726
 if (flags & A_HINT_DEREF) {
648  OP *o;
649
650
8726
  o = oi->old_pp(aTHX);
651
652
8726
  if (flags & (A_HINT_NOTIFY|A_HINT_STORE)) {
653
1311
   SPAGAIN;
654
1311
   if (a_undef(TOPs)) {
655
501
    if (flags & A_HINT_STRICT)
656
338
     croak("Reference vivification forbidden");
657
163
    else if (flags & A_HINT_WARN)
658
1
      warn("Reference was vivified");
659    else /* A_HINT_STORE */
660
162
     croak("Can't vivify reference");
661   }
662  }
663
664
8226
  return o;
665 }
666
667
8226
 return oi->old_pp(aTHX);
668}
669
670/* ... pp_root (exists,delete,keys,values) ................................. */
671
672
360
STATIC OP *a_pp_root_unop(pTHX) {
673
360
 dSP;
674
675
360
 if (a_undef(TOPs)) {
676
288
  POPs;
677  /* Can only be reached by keys or values */
678
288
  if (GIMME_V == G_SCALAR) {
679
144
   dTARGET;
680
144
   PUSHi(0);
681  }
682
288
  RETURN;
683 }
684
685 {
686  dA_MAP_THX;
687
72
  const a_op_info *oi = a_map_fetch(PL_op);
688
360
  return oi->old_pp(aTHX);
689 }
690}
691
692
2303
STATIC OP *a_pp_root_binop(pTHX) {
693
2303
 dSP;
694
695
2303
 if (a_undef(TOPm1s)) {
696
1870
  POPs;
697
1870
  POPs;
698
1870
  if (PL_op->op_type == OP_EXISTS)
699
935
   RETPUSHNO;
700  else
701
935
   RETPUSHUNDEF;
702 }
703
704 {
705  dA_MAP_THX;
706
433
  const a_op_info *oi = a_map_fetch(PL_op);
707
2303
  return oi->old_pp(aTHX);
708 }
709}
710
711/* --- Check functions ----------------------------------------------------- */
712
713
8536
STATIC void a_recheck_rv2xv(pTHX_ OP *o, OPCODE type, OP *(*new_pp)(pTHX)) {
714#define a_recheck_rv2xv(O, T, PP) a_recheck_rv2xv(aTHX_ (O), (T), (PP))
715
716
8536
 if (o->op_type == type && o->op_ppaddr != new_pp
717
2503
                        && cUNOPo->op_first->op_type != OP_GV) {
718  dA_MAP_THX;
719
1534
  const a_op_info *oi = a_map_fetch(o);
720
1534
  if (oi) {
721
1534
   a_map_store(o, o->op_ppaddr, oi->next, oi->flags);
722
8536
   o->op_ppaddr = new_pp;
723  }
724 }
725
726 return;
727}
728
729/* ... ck_pad{any,sv} ...................................................... */
730
731/* Sadly, the padsv OPs we are interested in don't trigger the padsv check
732 * function, but are instead manually mutated from a padany. So we store
733 * the op entry in the op map in the padany check function, and we set their
734 * op_ppaddr member in our peephole optimizer replacement below. */
735
736STATIC OP *(*a_old_ck_padany)(pTHX_ OP *) = 0;
737
738
139021
STATIC OP *a_ck_padany(pTHX_ OP *o) {
739 UV hint;
740
741
139021
 o = a_old_ck_padany(aTHX_ o);
742
743
139021
 hint = a_hint();
744
139021
 if (hint & A_HINT_DO)
745
7270
  a_map_store_root(o, o->op_ppaddr, hint);
746 else
747
131751
  a_map_delete(o);
748
749
139021
 return o;
750}
751
752STATIC OP *(*a_old_ck_padsv)(pTHX_ OP *) = 0;
753
754
2
STATIC OP *a_ck_padsv(pTHX_ OP *o) {
755 UV hint;
756
757
2
 o = a_old_ck_padsv(aTHX_ o);
758
759
2
 hint = a_hint();
760
2
 if (hint & A_HINT_DO) {
761
1
  a_map_store_root(o, o->op_ppaddr, hint);
762
1
  o->op_ppaddr = a_pp_deref;
763 } else
764
1
  a_map_delete(o);
765
766
2
 return o;
767}
768
769/* ... ck_deref (aelem,helem,rv2sv) ........................................ */
770
771/* Those ops appear both at the root and inside an expression but there's no
772 * way to distinguish both situations. Worse, we can't even know if we are in a
773 * modifying context, so the expression can't be resolved yet. It will be at the
774 * first invocation of a_pp_deref() for this expression. */
775
776STATIC OP *(*a_old_ck_aelem)(pTHX_ OP *) = 0;
777STATIC OP *(*a_old_ck_helem)(pTHX_ OP *) = 0;
778STATIC OP *(*a_old_ck_rv2sv)(pTHX_ OP *) = 0;
779
780
133646
STATIC OP *a_ck_deref(pTHX_ OP *o) {
781
133646
 OP * (*old_ck)(pTHX_ OP *o) = 0;
782
133646
 UV hint = a_hint();
783
784
133646
 switch (o->op_type) {
785  case OP_AELEM:
786
65341
   old_ck = a_old_ck_aelem;
787
65341
   if ((hint & A_HINT_DO) && !(hint & A_HINT_STRICT))
788
6277
    a_recheck_rv2xv(cUNOPo->op_first, OP_RV2AV, a_pp_rv2av);
789
65341
   break;
790  case OP_HELEM:
791
15957
   old_ck = a_old_ck_helem;
792
15957
   if ((hint & A_HINT_DO) && !(hint & A_HINT_STRICT))
793
2132
    a_recheck_rv2xv(cUNOPo->op_first, OP_RV2HV, a_pp_rv2hv_simple);
794
15957
   break;
795  case OP_RV2SV:
796
52348
   old_ck = a_old_ck_rv2sv;
797
52348
   break;
798 }
799
133646
 o = old_ck(aTHX_ o);
800
801
133646
 if (hint & A_HINT_DO) {
802
22965
  a_map_store_root(o, o->op_ppaddr, hint);
803
22965
  o->op_ppaddr = a_pp_deref;
804 } else
805
110681
  a_map_delete(o);
806
807
133646
 return o;
808}
809
810/* ... ck_rv2xv (rv2av,rv2hv) .............................................. */
811
812/* Those ops also appear both inisde and at the root, hence the caveats for
813 * a_ck_deref() still apply here. Since a padsv/rv2sv must appear before a
814 * rv2[ah]v, resolution is handled by the first call to a_pp_deref() in the
815 * expression. */
816
817STATIC OP *(*a_old_ck_rv2av)(pTHX_ OP *) = 0;
818STATIC OP *(*a_old_ck_rv2hv)(pTHX_ OP *) = 0;
819
820
29463
STATIC OP *a_ck_rv2xv(pTHX_ OP *o) {
821
29463
 OP * (*old_ck)(pTHX_ OP *o) = 0;
822
29463
 OP * (*new_pp)(pTHX) = 0;
823 UV hint;
824
825
29463
 switch (o->op_type) {
826
22514
  case OP_RV2AV: old_ck = a_old_ck_rv2av; new_pp = a_pp_rv2av; break;
827
6949
  case OP_RV2HV: old_ck = a_old_ck_rv2hv; new_pp = a_pp_rv2hv_simple; break;
828 }
829
29463
 o = old_ck(aTHX_ o);
830
831
29463
 if (cUNOPo->op_first->op_type == OP_GV)
832
15795
  return o;
833
834
13668
 hint = a_hint();
835
13668
 if (hint & A_HINT_DO && !(hint & A_HINT_STRICT)) {
836
4332
  a_map_store_root(o, o->op_ppaddr, hint);
837
4332
  o->op_ppaddr = new_pp;
838 } else
839
9336
  a_map_delete(o);
840
841
29463
 return o;
842}
843
844/* ... ck_xslice (aslice,hslice) ........................................... */
845
846/* I think those are only found at the root, but there's nothing that really
847 * prevent them to be inside the expression too. We only need to update the
848 * root so that the rest of the expression will see the right context when
849 * resolving. That's why we don't replace the ppaddr. */
850
851STATIC OP *(*a_old_ck_aslice)(pTHX_ OP *) = 0;
852STATIC OP *(*a_old_ck_hslice)(pTHX_ OP *) = 0;
853
854
431
STATIC OP *a_ck_xslice(pTHX_ OP *o) {
855
431
 OP * (*old_ck)(pTHX_ OP *o) = 0;
856
431
 UV hint = a_hint();
857
858
431
 switch (o->op_type) {
859  case OP_ASLICE:
860
286
   old_ck = a_old_ck_aslice;
861
286
   break;
862  case OP_HSLICE:
863
145
   old_ck = a_old_ck_hslice;
864
145
   if (hint & A_HINT_DO)
865
127
    a_recheck_rv2xv(cUNOPo->op_first->op_sibling, OP_RV2HV, a_pp_rv2hv);
866
145
   break;
867 }
868
431
 o = old_ck(aTHX_ o);
869
870
431
 if (hint & A_HINT_DO) {
871
377
  a_map_store_root(o, 0, hint);
872 } else
873
54
  a_map_delete(o);
874
875
431
 return o;
876}
877
878/* ... ck_root (exists,delete,keys,values) ................................. */
879
880/* Those ops are only found at the root of a dereferencing expression. We can
881 * then resolve at compile time if vivification must take place or not. */
882
883STATIC OP *(*a_old_ck_exists)(pTHX_ OP *) = 0;
884STATIC OP *(*a_old_ck_delete)(pTHX_ OP *) = 0;
885STATIC OP *(*a_old_ck_keys) (pTHX_ OP *) = 0;
886STATIC OP *(*a_old_ck_values)(pTHX_ OP *) = 0;
887
888
4416
STATIC OP *a_ck_root(pTHX_ OP *o) {
889
4416
 OP * (*old_ck)(pTHX_ OP *o) = 0;
890
4416
 OP * (*new_pp)(pTHX) = 0;
891
4416
 bool enabled = FALSE;
892
4416
 UV hint = a_hint();
893
894
4416
 switch (o->op_type) {
895  case OP_EXISTS:
896
1665
   old_ck = a_old_ck_exists;
897
1665
   new_pp = a_pp_root_binop;
898
1665
   enabled = hint & A_HINT_EXISTS;
899
1665
   break;
900  case OP_DELETE:
901
1620
   old_ck = a_old_ck_delete;
902
1620
   new_pp = a_pp_root_binop;
903
1620
   enabled = hint & A_HINT_DELETE;
904
1620
   break;
905  case OP_KEYS:
906
567
   old_ck = a_old_ck_keys;
907
567
   new_pp = a_pp_root_unop;
908
567
   enabled = hint & A_HINT_FETCH;
909
567
   break;
910  case OP_VALUES:
911
564
   old_ck = a_old_ck_values;
912
564
   new_pp = a_pp_root_unop;
913
564
   enabled = hint & A_HINT_FETCH;
914
564
   break;
915 }
916
4416
 o = old_ck(aTHX_ o);
917
918
4416
 if (hint & A_HINT_DO) {
919
4079
  if (enabled) {
920
1271
   a_map_update_flags_topdown(o, hint | A_HINT_DEREF);
921
1271
   a_map_store_root(o, o->op_ppaddr, hint);
922
1271
   o->op_ppaddr = new_pp;
923  } else {
924
2808
   a_map_cancel(o);
925  }
926 } else
927
337
  a_map_delete(o);
928
929
4416
 return o;
930}
931
932/* ... Our peephole optimizer .............................................. */
933
934STATIC peep_t a_old_peep = 0; /* This is actually the rpeep past 5.13.5 */
935
936STATIC void a_peep_rec(pTHX_ OP *o, ptable *seen);
937
938
49617
STATIC void a_peep_rec(pTHX_ OP *o, ptable *seen) {
939#define a_peep_rec(O) a_peep_rec(aTHX_ (O), seen)
940
1714614
 for (; o; o = o->op_next) {
941  dA_MAP_THX;
942
1665000
  const a_op_info *oi = NULL;
943
1665000
  UV flags = 0;
944
945
1665000
  if (ptable_fetch(seen, o))
946
3
   break;
947
1664997
  ptable_seen_store(seen, o, o);
948
949
1664997
  switch (o->op_type) {
950   case OP_PADSV:
951
120283
    if (o->op_ppaddr != a_pp_deref) {
952
120253
     oi = a_map_fetch(o);
953
120253
     if (oi && (oi->flags & A_HINT_DO)) {
954
1469
      a_map_store(o, o->op_ppaddr, oi->next, oi->flags);
955
1469
      o->op_ppaddr = a_pp_deref;
956     }
957    }
958    /* FALLTHROUGH */
959   case OP_AELEM:
960   case OP_AELEMFAST:
961   case OP_HELEM:
962   case OP_RV2SV:
963
233390
    if (o->op_ppaddr != a_pp_deref)
964
220346
     break;
965
13044
    oi = a_map_fetch(o);
966
13044
    if (!oi)
967
0
     break;
968
13044
    flags = oi->flags;
969
13044
    if (!(flags & A_HINT_DEREF)
970
11098
        && (flags & A_HINT_DO)
971
4166
        && (o->op_private & OPpDEREF || flags & A_HINT_ROOT)) {
972     /* Decide if the expression must autovivify or not. */
973
4082
     flags = a_map_resolve(o, oi);
974    }
975
13044
    if (flags & A_HINT_DEREF)
976
2949
     o->op_private = ((o->op_private & ~OPpDEREF) | OPpLVAL_DEFER);
977    else
978
10095
     o->op_ppaddr = oi->old_pp;
979
13044
    break;
980   case OP_RV2AV:
981   case OP_RV2HV:
982
47046
    if ( o->op_ppaddr != a_pp_rv2av
983
43293
        && o->op_ppaddr != a_pp_rv2hv
984
43201
        && o->op_ppaddr != a_pp_rv2hv_simple)
985
41193
     break;
986
5853
    oi = a_map_fetch(o);
987
5853
    if (!oi)
988
0
     break;
989
5853
    if (!(oi->flags & A_HINT_DEREF))
990
3915
     o->op_ppaddr = oi->old_pp;
991
5853
    break;
992#if !A_HAS_RPEEP
993   case OP_MAPWHILE:
994   case OP_GREPWHILE:
995   case OP_AND:
996   case OP_OR:
997   case OP_ANDASSIGN:
998   case OP_ORASSIGN:
999   case OP_COND_EXPR:
1000   case OP_RANGE:
1001# if A_HAS_PERL(5, 10, 0)
1002   case OP_ONCE:
1003   case OP_DOR:
1004   case OP_DORASSIGN:
1005# endif
1006    a_peep_rec(cLOGOPo->op_other);
1007    break;
1008   case OP_ENTERLOOP:
1009   case OP_ENTERITER:
1010    a_peep_rec(cLOOPo->op_redoop);
1011    a_peep_rec(cLOOPo->op_nextop);
1012    a_peep_rec(cLOOPo->op_lastop);
1013    break;
1014# if A_HAS_PERL(5, 9, 5)
1015   case OP_SUBST:
1016    a_peep_rec(cPMOPo->op_pmstashstartu.op_pmreplstart);
1017    break;
1018# else
1019   case OP_QR:
1020   case OP_MATCH:
1021   case OP_SUBST:
1022    a_peep_rec(cPMOPo->op_pmreplstart);
1023    break;
1024# endif
1025#endif /* !A_HAS_RPEEP */
1026   default:
1027
1384561
    break;
1028  }
1029 }
1030
49617
}
1031
1032
49617
STATIC void a_peep(pTHX_ OP *o) {
1033 dMY_CXT;
1034
49617
 ptable *seen = MY_CXT.seen;
1035
1036
49617
 a_old_peep(aTHX_ o);
1037
1038
49617
 ptable_seen_clear(seen);
1039
49617
 a_peep_rec(o);
1040
49617
 ptable_seen_clear(seen);
1041
49617
}
1042
1043/* --- Interpreter setup/teardown ------------------------------------------ */
1044
1045STATIC U32 a_initialized = 0;
1046
1047
15
STATIC void a_teardown(pTHX_ void *root) {
1048
1049
15
 if (!a_initialized)
1050
0
  return;
1051
1052#if A_MULTIPLICITY
1053 if (aTHX != root)
1054  return;
1055#endif
1056
1057 {
1058  dMY_CXT;
1059# if A_THREADSAFE && A_WORKAROUND_REQUIRE_PROPAGATION
1060  ptable_hints_free(MY_CXT.tbl);
1061# endif /* A_THREADSAFE && A_WORKAROUND_REQUIRE_PROPAGATION */
1062
15
  ptable_seen_free(MY_CXT.seen);
1063 }
1064
1065
15
 PL_check[OP_PADANY] = MEMBER_TO_FPTR(a_old_ck_padany);
1066
15
 a_old_ck_padany = 0;
1067
15
 PL_check[OP_PADSV] = MEMBER_TO_FPTR(a_old_ck_padsv);
1068
15
 a_old_ck_padsv = 0;
1069
1070
15
 PL_check[OP_AELEM] = MEMBER_TO_FPTR(a_old_ck_aelem);
1071
15
 a_old_ck_aelem = 0;
1072
15
 PL_check[OP_HELEM] = MEMBER_TO_FPTR(a_old_ck_helem);
1073
15
 a_old_ck_helem = 0;
1074
15
 PL_check[OP_RV2SV] = MEMBER_TO_FPTR(a_old_ck_rv2sv);
1075
15
 a_old_ck_rv2sv = 0;
1076
1077
15
 PL_check[OP_RV2AV] = MEMBER_TO_FPTR(a_old_ck_rv2av);
1078
15
 a_old_ck_rv2av = 0;
1079
15
 PL_check[OP_RV2HV] = MEMBER_TO_FPTR(a_old_ck_rv2hv);
1080
15
 a_old_ck_rv2hv = 0;
1081
1082
15
 PL_check[OP_ASLICE] = MEMBER_TO_FPTR(a_old_ck_aslice);
1083
15
 a_old_ck_aslice = 0;
1084
15
 PL_check[OP_HSLICE] = MEMBER_TO_FPTR(a_old_ck_hslice);
1085
15
 a_old_ck_hslice = 0;
1086
1087
15
 PL_check[OP_EXISTS] = MEMBER_TO_FPTR(a_old_ck_exists);
1088
15
 a_old_ck_exists = 0;
1089
15
 PL_check[OP_DELETE] = MEMBER_TO_FPTR(a_old_ck_delete);
1090
15
 a_old_ck_delete = 0;
1091
15
 PL_check[OP_KEYS] = MEMBER_TO_FPTR(a_old_ck_keys);
1092
15
 a_old_ck_keys = 0;
1093
15
 PL_check[OP_VALUES] = MEMBER_TO_FPTR(a_old_ck_values);
1094
15
 a_old_ck_values = 0;
1095
1096#if A_HAS_RPEEP
1097
15
 PL_rpeepp = a_old_peep;
1098#else
1099 PL_peepp = a_old_peep;
1100#endif
1101
15
 a_old_peep = 0;
1102
1103
15
 a_initialized = 0;
1104}
1105
1106
15
STATIC void a_setup(pTHX) {
1107#define a_setup() a_setup(aTHX)
1108
15
 if (a_initialized)
1109
0
  return;
1110
1111 {
1112  MY_CXT_INIT;
1113# if A_THREADSAFE && A_WORKAROUND_REQUIRE_PROPAGATION
1114  MY_CXT.tbl = ptable_new();
1115  MY_CXT.owner = aTHX;
1116# endif /* A_THREADSAFE && A_WORKAROUND_REQUIRE_PROPAGATION */
1117
15
  MY_CXT.seen = ptable_new();
1118 }
1119
1120
15
 a_old_ck_padany = PL_check[OP_PADANY];
1121
15
 PL_check[OP_PADANY] = MEMBER_TO_FPTR(a_ck_padany);
1122
15
 a_old_ck_padsv = PL_check[OP_PADSV];
1123
15
 PL_check[OP_PADSV] = MEMBER_TO_FPTR(a_ck_padsv);
1124
1125
15
 a_old_ck_aelem = PL_check[OP_AELEM];
1126
15
 PL_check[OP_AELEM] = MEMBER_TO_FPTR(a_ck_deref);
1127
15
 a_old_ck_helem = PL_check[OP_HELEM];
1128
15
 PL_check[OP_HELEM] = MEMBER_TO_FPTR(a_ck_deref);
1129
15
 a_old_ck_rv2sv = PL_check[OP_RV2SV];
1130
15
 PL_check[OP_RV2SV] = MEMBER_TO_FPTR(a_ck_deref);
1131
1132
15
 a_old_ck_rv2av = PL_check[OP_RV2AV];
1133
15
 PL_check[OP_RV2AV] = MEMBER_TO_FPTR(a_ck_rv2xv);
1134
15
 a_old_ck_rv2hv = PL_check[OP_RV2HV];
1135
15
 PL_check[OP_RV2HV] = MEMBER_TO_FPTR(a_ck_rv2xv);
1136
1137
15
 a_old_ck_aslice = PL_check[OP_ASLICE];
1138
15
 PL_check[OP_ASLICE] = MEMBER_TO_FPTR(a_ck_xslice);
1139
15
 a_old_ck_hslice = PL_check[OP_HSLICE];
1140
15
 PL_check[OP_HSLICE] = MEMBER_TO_FPTR(a_ck_xslice);
1141
1142
15
 a_old_ck_exists = PL_check[OP_EXISTS];
1143
15
 PL_check[OP_EXISTS] = MEMBER_TO_FPTR(a_ck_root);
1144
15
 a_old_ck_delete = PL_check[OP_DELETE];
1145
15
 PL_check[OP_DELETE] = MEMBER_TO_FPTR(a_ck_root);
1146
15
 a_old_ck_keys = PL_check[OP_KEYS];
1147
15
 PL_check[OP_KEYS] = MEMBER_TO_FPTR(a_ck_root);
1148
15
 a_old_ck_values = PL_check[OP_VALUES];
1149
15
 PL_check[OP_VALUES] = MEMBER_TO_FPTR(a_ck_root);
1150
1151#if A_HAS_RPEEP
1152
15
 a_old_peep = PL_rpeepp;
1153
15
 PL_rpeepp = a_peep;
1154#else
1155 a_old_peep = PL_peepp;
1156 PL_peepp = a_peep;
1157#endif
1158
1159#if A_MULTIPLICITY
1160 call_atexit(a_teardown, aTHX);
1161#else
1162
15
 call_atexit(a_teardown, NULL);
1163#endif
1164
1165
15
 a_initialized = 1;
1166}
1167
1168STATIC U32 a_booted = 0;
1169
1170/* --- XS ------------------------------------------------------------------ */
1171
1172MODULE = autovivification PACKAGE = autovivification
1173
1174PROTOTYPES: ENABLE
1175
1176BOOT:
1177{
1178
15
 if (!a_booted++) {
1179  HV *stash;
1180
1181
15
  a_op_map = ptable_new();
1182#ifdef USE_ITHREADS
1183  MUTEX_INIT(&a_op_map_mutex);
1184#endif
1185
1186
255
  PERL_HASH(a_hash, __PACKAGE__, __PACKAGE_LEN__);
1187
1188
15
  stash = gv_stashpvn(__PACKAGE__, __PACKAGE_LEN__, 1);
1189
15
  newCONSTSUB(stash, "A_HINT_STRICT", newSVuv(A_HINT_STRICT));
1190
15
  newCONSTSUB(stash, "A_HINT_WARN", newSVuv(A_HINT_WARN));
1191
15
  newCONSTSUB(stash, "A_HINT_FETCH", newSVuv(A_HINT_FETCH));
1192
15
  newCONSTSUB(stash, "A_HINT_STORE", newSVuv(A_HINT_STORE));
1193
15
  newCONSTSUB(stash, "A_HINT_EXISTS", newSVuv(A_HINT_EXISTS));
1194
15
  newCONSTSUB(stash, "A_HINT_DELETE", newSVuv(A_HINT_DELETE));
1195
15
  newCONSTSUB(stash, "A_HINT_MASK", newSVuv(A_HINT_MASK));
1196
15
  newCONSTSUB(stash, "A_THREADSAFE", newSVuv(A_THREADSAFE));
1197
15
  newCONSTSUB(stash, "A_FORKSAFE", newSVuv(A_FORKSAFE));
1198 }
1199
1200
15
 a_setup();
1201}
1202
1203#if A_THREADSAFE
1204
1205void
1206CLONE(...)
1207PROTOTYPE: DISABLE
1208PREINIT:
1209#if A_WORKAROUND_REQUIRE_PROPAGATION
1210 ptable *t;
1211#endif
1212 ptable *s;
1213PPCODE:
1214 {
1215  dMY_CXT;
1216#if A_WORKAROUND_REQUIRE_PROPAGATION
1217  {
1218   a_ptable_clone_ud ud;
1219
1220   t = ptable_new();
1221   a_ptable_clone_ud_init(ud, t, MY_CXT.owner);
1222   ptable_walk(MY_CXT.tbl, a_ptable_clone, &ud);
1223   a_ptable_clone_ud_deinit(ud);
1224  }
1225#endif
1226  s = ptable_new();
1227 }
1228 {
1229  MY_CXT_CLONE;
1230#if A_WORKAROUND_REQUIRE_PROPAGATION
1231  MY_CXT.tbl = t;
1232  MY_CXT.owner = aTHX;
1233#endif
1234  MY_CXT.seen = s;
1235 }
1236 reap(3, a_thread_cleanup, NULL);
1237 XSRETURN(0);
1238
1239#endif /* A_THREADSAFE */
1240
1241SV *
1242_tag(SV *hint)
1243PROTOTYPE: $
1244CODE:
1245
12381
 RETVAL = a_tag(SvOK(hint) ? SvUV(hint) : 0);
1246OUTPUT:
1247 RETVAL
1248
1249SV *
1250_detag(SV *tag)
1251PROTOTYPE: $
1252CODE:
1253
12380
 if (!SvOK(tag))
1254
8771
  XSRETURN_UNDEF;
1255
3609
 RETVAL = newSVuv(a_detag(tag));
1256OUTPUT:
1257 RETVAL