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1/* pad.c
2 *
b5c19bd7 3 * Copyright (C) 2002,2003 by Larry Wall and others
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4 *
5 * You may distribute under the terms of either the GNU General Public
6 * License or the Artistic License, as specified in the README file.
7 *
8 * "Anyway: there was this Mr Frodo left an orphan and stranded, as you
9 * might say, among those queer Bucklanders, being brought up anyhow in
10 * Brandy Hall. A regular warren, by all accounts. Old Master Gorbadoc
11 * never had fewer than a couple of hundred relations in the place. Mr
12 * Bilbo never did a kinder deed than when he brought the lad back to
13 * live among decent folk." --the Gaffer
14 */
15
16/* XXX DAPM
17 * As of Sept 2002, this file is new and may be in a state of flux for
18 * a while. I've marked things I intent to come back and look at further
19 * with an 'XXX DAPM' comment.
20 */
21
22/*
23=head1 Pad Data Structures
24
25=for apidoc m|AV *|CvPADLIST|CV *cv
26CV's can have CvPADLIST(cv) set to point to an AV.
27
28For these purposes "forms" are a kind-of CV, eval""s are too (except they're
29not callable at will and are always thrown away after the eval"" is done
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30executing). Require'd files are simply evals without any outer lexical
31scope.
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32
33XSUBs don't have CvPADLIST set - dXSTARG fetches values from PL_curpad,
34but that is really the callers pad (a slot of which is allocated by
35every entersub).
36
37The CvPADLIST AV has does not have AvREAL set, so REFCNT of component items
f3548bdc 38is managed "manual" (mostly in pad.c) rather than normal av.c rules.
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39The items in the AV are not SVs as for a normal AV, but other AVs:
40
410'th Entry of the CvPADLIST is an AV which represents the "names" or rather
42the "static type information" for lexicals.
43
44The CvDEPTH'th entry of CvPADLIST AV is an AV which is the stack frame at that
45depth of recursion into the CV.
46The 0'th slot of a frame AV is an AV which is @_.
47other entries are storage for variables and op targets.
48
49During compilation:
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50C<PL_comppad_name> is set to the names AV.
51C<PL_comppad> is set to the frame AV for the frame CvDEPTH == 1.
52C<PL_curpad> is set to the body of the frame AV (i.e. AvARRAY(PL_comppad)).
dd2155a4 53
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54During execution, C<PL_comppad> and C<PL_curpad> refer to the live
55frame of the currently executing sub.
56
57Iterating over the names AV iterates over all possible pad
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58items. Pad slots that are SVs_PADTMP (targets/GVs/constants) end up having
59&PL_sv_undef "names" (see pad_alloc()).
60
61Only my/our variable (SVs_PADMY/SVs_PADOUR) slots get valid names.
62The rest are op targets/GVs/constants which are statically allocated
63or resolved at compile time. These don't have names by which they
64can be looked up from Perl code at run time through eval"" like
65my/our variables can be. Since they can't be looked up by "name"
66but only by their index allocated at compile time (which is usually
67in PL_op->op_targ), wasting a name SV for them doesn't make sense.
68
69The SVs in the names AV have their PV being the name of the variable.
70NV+1..IV inclusive is a range of cop_seq numbers for which the name is
71valid. For typed lexicals name SV is SVt_PVMG and SvSTASH points at the
72type. For C<our> lexicals, the type is SVt_PVGV, and GvSTASH points at the
73stash of the associated global (so that duplicate C<our> delarations in the
74same package can be detected). SvCUR is sometimes hijacked to
75store the generation number during compilation.
76
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77If SvFAKE is set on the name SV, then that slot in the frame AV is
78a REFCNT'ed reference to a lexical from "outside". In this case,
79the name SV does not use NVX and IVX to store a cop_seq range, since it is
80in scope throughout. Instead IVX stores some flags containing info about
81the real lexical (is it declared in an anon, and is it capable of being
82instantiated multiple times?), and for fake ANONs, NVX contains the index
83within the parent's pad where the lexical's value is stored, to make
84cloning quicker.
dd2155a4 85
a6d05634 86If the 'name' is '&' the corresponding entry in frame AV
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87is a CV representing a possible closure.
88(SvFAKE and name of '&' is not a meaningful combination currently but could
89become so if C<my sub foo {}> is implemented.)
90
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91Note that formats are treated as anon subs, and are cloned each time
92write is called (if necessary).
93
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94The flag SVf_PADSTALE is cleared on lexicals each time the my() is executed,
95and set on scope exit. This allows the 'Variable $x is not available' warning
96to be generated in evals, such as
97
98 { my $x = 1; sub f { eval '$x'} } f();
99
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100=cut
101*/
102
103
104#include "EXTERN.h"
105#define PERL_IN_PAD_C
106#include "perl.h"
107
108
109#define PAD_MAX 999999999
110
111
112
113/*
114=for apidoc pad_new
115
116Create a new compiling padlist, saving and updating the various global
117vars at the same time as creating the pad itself. The following flags
118can be OR'ed together:
119
120 padnew_CLONE this pad is for a cloned CV
121 padnew_SAVE save old globals
122 padnew_SAVESUB also save extra stuff for start of sub
123
124=cut
125*/
126
127PADLIST *
c7c737cb 128Perl_pad_new(pTHX_ int flags)
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129{
130 AV *padlist, *padname, *pad, *a0;
131
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132 ASSERT_CURPAD_LEGAL("pad_new");
133
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134 /* XXX DAPM really need a new SAVEt_PAD which restores all or most
135 * vars (based on flags) rather than storing vals + addresses for
136 * each individually. Also see pad_block_start.
137 * XXX DAPM Try to see whether all these conditionals are required
138 */
139
140 /* save existing state, ... */
141
142 if (flags & padnew_SAVE) {
3979c56f 143 SAVECOMPPAD();
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144 SAVESPTR(PL_comppad_name);
145 if (! (flags & padnew_CLONE)) {
146 SAVEI32(PL_padix);
147 SAVEI32(PL_comppad_name_fill);
148 SAVEI32(PL_min_intro_pending);
149 SAVEI32(PL_max_intro_pending);
b5c19bd7 150 SAVEI32(PL_cv_has_eval);
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151 if (flags & padnew_SAVESUB) {
152 SAVEI32(PL_pad_reset_pending);
153 }
154 }
155 }
156 /* XXX DAPM interestingly, PL_comppad_name_floor never seems to be
157 * saved - check at some pt that this is okay */
158
159 /* ... create new pad ... */
160
161 padlist = newAV();
162 padname = newAV();
163 pad = newAV();
164
165 if (flags & padnew_CLONE) {
166 /* XXX DAPM I dont know why cv_clone needs it
167 * doing differently yet - perhaps this separate branch can be
168 * dispensed with eventually ???
169 */
170
171 a0 = newAV(); /* will be @_ */
172 av_extend(a0, 0);
173 av_store(pad, 0, (SV*)a0);
174 AvFLAGS(a0) = AVf_REIFY;
175 }
176 else {
dd2155a4 177 av_store(pad, 0, Nullsv);
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178 }
179
180 AvREAL_off(padlist);
181 av_store(padlist, 0, (SV*)padname);
182 av_store(padlist, 1, (SV*)pad);
183
184 /* ... then update state variables */
185
186 PL_comppad_name = (AV*)(*av_fetch(padlist, 0, FALSE));
187 PL_comppad = (AV*)(*av_fetch(padlist, 1, FALSE));
188 PL_curpad = AvARRAY(PL_comppad);
189
190 if (! (flags & padnew_CLONE)) {
191 PL_comppad_name_fill = 0;
192 PL_min_intro_pending = 0;
193 PL_padix = 0;
b5c19bd7 194 PL_cv_has_eval = 0;
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195 }
196
197 DEBUG_X(PerlIO_printf(Perl_debug_log,
b5c19bd7 198 "Pad 0x%"UVxf"[0x%"UVxf"] new: compcv=0x%"UVxf
dd2155a4 199 " name=0x%"UVxf" flags=0x%"UVxf"\n",
b5c19bd7 200 PTR2UV(PL_comppad), PTR2UV(PL_curpad), PTR2UV(PL_compcv),
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201 PTR2UV(padname), (UV)flags
202 )
203 );
204
205 return (PADLIST*)padlist;
206}
207
208/*
209=for apidoc pad_undef
210
211Free the padlist associated with a CV.
212If parts of it happen to be current, we null the relevant
213PL_*pad* global vars so that we don't have any dangling references left.
214We also repoint the CvOUTSIDE of any about-to-be-orphaned
a3985cdc 215inner subs to the outer of this cv.
dd2155a4 216
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217(This function should really be called pad_free, but the name was already
218taken)
219
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220=cut
221*/
222
223void
a3985cdc 224Perl_pad_undef(pTHX_ CV* cv)
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225{
226 I32 ix;
227 PADLIST *padlist = CvPADLIST(cv);
228
229 if (!padlist)
230 return;
231 if (!SvREFCNT(CvPADLIST(cv))) /* may be during global destruction */
232 return;
233
234 DEBUG_X(PerlIO_printf(Perl_debug_log,
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235 "Pad undef: cv=0x%"UVxf" padlist=0x%"UVxf"\n",
236 PTR2UV(cv), PTR2UV(padlist))
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237 );
238
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239 /* detach any '&' anon children in the pad; if afterwards they
240 * are still live, fix up their CvOUTSIDEs to point to our outside,
241 * bypassing us. */
242 /* XXX DAPM for efficiency, we should only do this if we know we have
243 * children, or integrate this loop with general cleanup */
dd2155a4 244
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245 if (!PL_dirty) { /* don't bother during global destruction */
246 CV *outercv = CvOUTSIDE(cv);
247 U32 seq = CvOUTSIDE_SEQ(cv);
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248 AV *comppad_name = (AV*)AvARRAY(padlist)[0];
249 SV **namepad = AvARRAY(comppad_name);
250 AV *comppad = (AV*)AvARRAY(padlist)[1];
251 SV **curpad = AvARRAY(comppad);
252 for (ix = AvFILLp(comppad_name); ix > 0; ix--) {
253 SV *namesv = namepad[ix];
254 if (namesv && namesv != &PL_sv_undef
7dafbf52 255 && *SvPVX(namesv) == '&')
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256 {
257 CV *innercv = (CV*)curpad[ix];
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258 namepad[ix] = Nullsv;
259 SvREFCNT_dec(namesv);
260 curpad[ix] = Nullsv;
261 SvREFCNT_dec(innercv);
262 if (SvREFCNT(innercv) /* in use, not just a prototype */
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263 && CvOUTSIDE(innercv) == cv)
264 {
7dafbf52 265 assert(CvWEAKOUTSIDE(innercv));
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266 /* don't relink to grandfather if he's being freed */
267 if (outercv && SvREFCNT(outercv)) {
268 CvWEAKOUTSIDE_off(innercv);
269 CvOUTSIDE(innercv) = outercv;
270 CvOUTSIDE_SEQ(innercv) = seq;
271 SvREFCNT_inc(outercv);
272 }
273 else {
274 CvOUTSIDE(innercv) = Nullcv;
275 }
276
dd2155a4 277 }
9d1ce744 278
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279 }
280 }
281 }
7dafbf52 282
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283 ix = AvFILLp(padlist);
284 while (ix >= 0) {
285 SV* sv = AvARRAY(padlist)[ix--];
286 if (!sv)
287 continue;
288 if (sv == (SV*)PL_comppad_name)
289 PL_comppad_name = Nullav;
290 else if (sv == (SV*)PL_comppad) {
f3548bdc 291 PL_comppad = Null(PAD*);
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292 PL_curpad = Null(SV**);
293 }
294 SvREFCNT_dec(sv);
295 }
296 SvREFCNT_dec((SV*)CvPADLIST(cv));
297 CvPADLIST(cv) = Null(PADLIST*);
298}
299
300
301
302
303/*
304=for apidoc pad_add_name
305
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306Create a new name and associated PADMY SV in the current pad; return the
307offset.
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308If C<typestash> is valid, the name is for a typed lexical; set the
309name's stash to that value.
310If C<ourstash> is valid, it's an our lexical, set the name's
311GvSTASH to that value
312
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313If fake, it means we're cloning an existing entry
314
315=cut
316*/
317
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318PADOFFSET
319Perl_pad_add_name(pTHX_ char *name, HV* typestash, HV* ourstash, bool fake)
320{
321 PADOFFSET offset = pad_alloc(OP_PADSV, SVs_PADMY);
322 SV* namesv = NEWSV(1102, 0);
dd2155a4 323
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324 ASSERT_CURPAD_ACTIVE("pad_add_name");
325
dd2155a4 326
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327 sv_upgrade(namesv, ourstash ? SVt_PVGV : typestash ? SVt_PVMG : SVt_PVNV);
328 sv_setpv(namesv, name);
329
330 if (typestash) {
331 SvFLAGS(namesv) |= SVpad_TYPED;
332 SvSTASH(namesv) = (HV*)SvREFCNT_inc((SV*) typestash);
333 }
334 if (ourstash) {
335 SvFLAGS(namesv) |= SVpad_OUR;
336 GvSTASH(namesv) = (HV*)SvREFCNT_inc((SV*) ourstash);
337 }
338
339 av_store(PL_comppad_name, offset, namesv);
b5c19bd7 340 if (fake) {
dd2155a4 341 SvFAKE_on(namesv);
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342 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
343 "Pad addname: %ld \"%s\" FAKE\n", (long)offset, name));
344 }
dd2155a4 345 else {
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346 /* not yet introduced */
347 SvNVX(namesv) = (NV)PAD_MAX; /* min */
348 SvIVX(namesv) = 0; /* max */
349
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350 if (!PL_min_intro_pending)
351 PL_min_intro_pending = offset;
352 PL_max_intro_pending = offset;
b5c19bd7 353 /* if it's not a simple scalar, replace with an AV or HV */
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354 /* XXX DAPM since slot has been allocated, replace
355 * av_store with PL_curpad[offset] ? */
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356 if (*name == '@')
357 av_store(PL_comppad, offset, (SV*)newAV());
358 else if (*name == '%')
359 av_store(PL_comppad, offset, (SV*)newHV());
360 SvPADMY_on(PL_curpad[offset]);
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361 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
362 "Pad addname: %ld \"%s\" new lex=0x%"UVxf"\n",
363 (long)offset, name, PTR2UV(PL_curpad[offset])));
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364 }
365
366 return offset;
367}
368
369
370
371
372/*
373=for apidoc pad_alloc
374
375Allocate a new my or tmp pad entry. For a my, simply push a null SV onto
376the end of PL_comppad, but for a tmp, scan the pad from PL_padix upwards
377for a slot which has no name and and no active value.
378
379=cut
380*/
381
382/* XXX DAPM integrate alloc(), add_name() and add_anon(),
383 * or at least rationalise ??? */
384
385
386PADOFFSET
387Perl_pad_alloc(pTHX_ I32 optype, U32 tmptype)
388{
389 SV *sv;
390 I32 retval;
391
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392 ASSERT_CURPAD_ACTIVE("pad_alloc");
393
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394 if (AvARRAY(PL_comppad) != PL_curpad)
395 Perl_croak(aTHX_ "panic: pad_alloc");
396 if (PL_pad_reset_pending)
397 pad_reset();
398 if (tmptype & SVs_PADMY) {
235cc2e3 399 sv = *av_fetch(PL_comppad, AvFILLp(PL_comppad) + 1, TRUE);
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400 retval = AvFILLp(PL_comppad);
401 }
402 else {
403 SV **names = AvARRAY(PL_comppad_name);
404 SSize_t names_fill = AvFILLp(PL_comppad_name);
405 for (;;) {
406 /*
407 * "foreach" index vars temporarily become aliases to non-"my"
408 * values. Thus we must skip, not just pad values that are
409 * marked as current pad values, but also those with names.
410 */
411 /* HVDS why copy to sv here? we don't seem to use it */
412 if (++PL_padix <= names_fill &&
413 (sv = names[PL_padix]) && sv != &PL_sv_undef)
414 continue;
415 sv = *av_fetch(PL_comppad, PL_padix, TRUE);
416 if (!(SvFLAGS(sv) & (SVs_PADTMP | SVs_PADMY)) &&
417 !IS_PADGV(sv) && !IS_PADCONST(sv))
418 break;
419 }
420 retval = PL_padix;
421 }
422 SvFLAGS(sv) |= tmptype;
423 PL_curpad = AvARRAY(PL_comppad);
424
425 DEBUG_X(PerlIO_printf(Perl_debug_log,
426 "Pad 0x%"UVxf"[0x%"UVxf"] alloc: %ld for %s\n",
427 PTR2UV(PL_comppad), PTR2UV(PL_curpad), (long) retval,
428 PL_op_name[optype]));
429 return (PADOFFSET)retval;
430}
431
432/*
433=for apidoc pad_add_anon
434
435Add an anon code entry to the current compiling pad
436
437=cut
438*/
439
440PADOFFSET
441Perl_pad_add_anon(pTHX_ SV* sv, OPCODE op_type)
442{
443 PADOFFSET ix;
444 SV* name;
445
446 name = NEWSV(1106, 0);
447 sv_upgrade(name, SVt_PVNV);
448 sv_setpvn(name, "&", 1);
449 SvIVX(name) = -1;
450 SvNVX(name) = 1;
451 ix = pad_alloc(op_type, SVs_PADMY);
452 av_store(PL_comppad_name, ix, name);
f3548bdc 453 /* XXX DAPM use PL_curpad[] ? */
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454 av_store(PL_comppad, ix, sv);
455 SvPADMY_on(sv);
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456
457 /* to avoid ref loops, we never have parent + child referencing each
458 * other simultaneously */
459 if (CvOUTSIDE((CV*)sv)) {
460 assert(!CvWEAKOUTSIDE((CV*)sv));
461 CvWEAKOUTSIDE_on((CV*)sv);
462 SvREFCNT_dec(CvOUTSIDE((CV*)sv));
463 }
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464 return ix;
465}
466
467
468
469/*
470=for apidoc pad_check_dup
471
472Check for duplicate declarations: report any of:
473 * a my in the current scope with the same name;
474 * an our (anywhere in the pad) with the same name and the same stash
475 as C<ourstash>
476C<is_our> indicates that the name to check is an 'our' declaration
477
478=cut
479*/
480
481/* XXX DAPM integrate this into pad_add_name ??? */
482
483void
484Perl_pad_check_dup(pTHX_ char *name, bool is_our, HV *ourstash)
485{
486 SV **svp, *sv;
487 PADOFFSET top, off;
488
f3548bdc 489 ASSERT_CURPAD_ACTIVE("pad_check_dup");
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490 if (!ckWARN(WARN_MISC) || AvFILLp(PL_comppad_name) < 0)
491 return; /* nothing to check */
492
493 svp = AvARRAY(PL_comppad_name);
494 top = AvFILLp(PL_comppad_name);
495 /* check the current scope */
496 /* XXX DAPM - why the (I32) cast - shouldn't we ensure they're the same
497 * type ? */
498 for (off = top; (I32)off > PL_comppad_name_floor; off--) {
499 if ((sv = svp[off])
500 && sv != &PL_sv_undef
ee6cee0c 501 && !SvFAKE(sv)
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502 && (SvIVX(sv) == PAD_MAX || SvIVX(sv) == 0)
503 && (!is_our
504 || ((SvFLAGS(sv) & SVpad_OUR) && GvSTASH(sv) == ourstash))
505 && strEQ(name, SvPVX(sv)))
506 {
507 Perl_warner(aTHX_ packWARN(WARN_MISC),
508 "\"%s\" variable %s masks earlier declaration in same %s",
509 (is_our ? "our" : "my"),
510 name,
511 (SvIVX(sv) == PAD_MAX ? "scope" : "statement"));
512 --off;
513 break;
514 }
515 }
516 /* check the rest of the pad */
517 if (is_our) {
518 do {
519 if ((sv = svp[off])
520 && sv != &PL_sv_undef
ee6cee0c 521 && !SvFAKE(sv)
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522 && (SvIVX(sv) == PAD_MAX || SvIVX(sv) == 0)
523 && ((SvFLAGS(sv) & SVpad_OUR) && GvSTASH(sv) == ourstash)
524 && strEQ(name, SvPVX(sv)))
525 {
526 Perl_warner(aTHX_ packWARN(WARN_MISC),
527 "\"our\" variable %s redeclared", name);
528 Perl_warner(aTHX_ packWARN(WARN_MISC),
529 "\t(Did you mean \"local\" instead of \"our\"?)\n");
530 break;
531 }
532 } while ( off-- > 0 );
533 }
534}
535
536
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537/*
538=for apidoc pad_findmy
539
540Given a lexical name, try to find its offset, first in the current pad,
541or failing that, in the pads of any lexically enclosing subs (including
542the complications introduced by eval). If the name is found in an outer pad,
543then a fake entry is added to the current pad.
544Returns the offset in the current pad, or NOT_IN_PAD on failure.
545
546=cut
547*/
548
549PADOFFSET
550Perl_pad_findmy(pTHX_ char *name)
551{
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552 SV *out_sv;
553 int out_flags;
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554 I32 offset;
555 AV *nameav;
556 SV **name_svp;
dd2155a4 557
929a0744 558 offset = pad_findlex(name, PL_compcv, PL_cop_seqmax, 1,
b5c19bd7 559 Null(SV**), &out_sv, &out_flags);
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560 if (offset != NOT_IN_PAD)
561 return offset;
562
563 /* look for an our that's being introduced; this allows
564 * our $foo = 0 unless defined $foo;
565 * to not give a warning. (Yes, this is a hack) */
566
567 nameav = (AV*)AvARRAY(CvPADLIST(PL_compcv))[0];
568 name_svp = AvARRAY(nameav);
569 for (offset = AvFILLp(nameav); offset > 0; offset--) {
570 SV *namesv = name_svp[offset];
571 if (namesv && namesv != &PL_sv_undef
572 && !SvFAKE(namesv)
573 && (SvFLAGS(namesv) & SVpad_OUR)
574 && strEQ(SvPVX(namesv), name)
4cf4a199 575 && U_32(SvNVX(namesv)) == PAD_MAX /* min */
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576 )
577 return offset;
578 }
579 return NOT_IN_PAD;
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580}
581
582
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583/*
584=for apidoc pad_findlex
585
586Find a named lexical anywhere in a chain of nested pads. Add fake entries
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587in the inner pads if it's found in an outer one.
588
589Returns the offset in the bottom pad of the lex or the fake lex.
590cv is the CV in which to start the search, and seq is the current cop_seq
591to match against. If warn is true, print appropriate warnings. The out_*
592vars return values, and so are pointers to where the returned values
593should be stored. out_capture, if non-null, requests that the innermost
594instance of the lexical is captured; out_name_sv is set to the innermost
595matched namesv or fake namesv; out_flags returns the flags normally
596associated with the IVX field of a fake namesv.
597
598Note that pad_findlex() is recursive; it recurses up the chain of CVs,
599then comes back down, adding fake entries as it goes. It has to be this way
600because fake namesvs in anon protoypes have to store in NVX the index into
601the parent pad.
dd2155a4
DM
602
603=cut
604*/
605
b5c19bd7
DM
606/* Flags set in the SvIVX field of FAKE namesvs */
607
608#define PAD_FAKELEX_ANON 1 /* the lex is declared in an ANON, or ... */
609#define PAD_FAKELEX_MULTI 2 /* the lex can be instantiated multiple times */
610
611/* the CV has finished being compiled. This is not a sufficient test for
612 * all CVs (eg XSUBs), but suffices for the CVs found in a lexical chain */
613#define CvCOMPILED(cv) CvROOT(cv)
614
71f882da
DM
615/* the CV does late binding of its lexicals */
616#define CvLATE(cv) (CvANON(cv) || SvTYPE(cv) == SVt_PVFM)
617
b5c19bd7 618
dd2155a4 619STATIC PADOFFSET
b5c19bd7
DM
620S_pad_findlex(pTHX_ char *name, CV* cv, U32 seq, int warn,
621 SV** out_capture, SV** out_name_sv, int *out_flags)
dd2155a4 622{
b5c19bd7
DM
623 I32 offset, new_offset;
624 SV *new_capture;
625 SV **new_capturep;
626 AV *padlist = CvPADLIST(cv);
dd2155a4 627
b5c19bd7 628 *out_flags = 0;
a3985cdc 629
b5c19bd7
DM
630 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
631 "Pad findlex cv=0x%"UVxf" searching \"%s\" seq=%d%s\n",
632 PTR2UV(cv), name, (int)seq, out_capture ? " capturing" : "" ));
dd2155a4 633
b5c19bd7 634 /* first, search this pad */
dd2155a4 635
b5c19bd7
DM
636 if (padlist) { /* not an undef CV */
637 I32 fake_offset = 0;
638 AV *nameav = (AV*)AvARRAY(padlist)[0];
639 SV **name_svp = AvARRAY(nameav);
ee6cee0c 640
b5c19bd7
DM
641 for (offset = AvFILLp(nameav); offset > 0; offset--) {
642 SV *namesv = name_svp[offset];
643 if (namesv && namesv != &PL_sv_undef
644 && strEQ(SvPVX(namesv), name))
645 {
646 if (SvFAKE(namesv))
647 fake_offset = offset; /* in case we don't find a real one */
4cf4a199
JH
648 else if ( seq > U_32(SvNVX(namesv)) /* min */
649 && seq <= (U32)SvIVX(namesv)) /* max */
b5c19bd7 650 break;
ee6cee0c
DM
651 }
652 }
653
b5c19bd7
DM
654 if (offset > 0 || fake_offset > 0 ) { /* a match! */
655 if (offset > 0) { /* not fake */
656 fake_offset = 0;
657 *out_name_sv = name_svp[offset]; /* return the namesv */
658
659 /* set PAD_FAKELEX_MULTI if this lex can have multiple
660 * instances. For now, we just test !CvUNIQUE(cv), but
661 * ideally, we should detect my's declared within loops
662 * etc - this would allow a wider range of 'not stayed
663 * shared' warnings. We also treated alreadly-compiled
664 * lexes as not multi as viewed from evals. */
665
666 *out_flags = CvANON(cv) ?
667 PAD_FAKELEX_ANON :
668 (!CvUNIQUE(cv) && ! CvCOMPILED(cv))
669 ? PAD_FAKELEX_MULTI : 0;
670
671 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
672 "Pad findlex cv=0x%"UVxf" matched: offset=%ld (%ld,%ld)\n",
4cf4a199 673 PTR2UV(cv), (long)offset, (long)U_32(SvNVX(*out_name_sv)),
b5c19bd7
DM
674 (long)SvIVX(*out_name_sv)));
675 }
676 else { /* fake match */
677 offset = fake_offset;
678 *out_name_sv = name_svp[offset]; /* return the namesv */
679 *out_flags = SvIVX(*out_name_sv);
680 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
19a5c512 681 "Pad findlex cv=0x%"UVxf" matched: offset=%ld flags=0x%lx index=%lu\n",
b5c19bd7
DM
682 PTR2UV(cv), (long)offset, (unsigned long)*out_flags,
683 (unsigned long)SvNVX(*out_name_sv)
684 ));
685 }
dd2155a4 686
b5c19bd7 687 /* return the lex? */
dd2155a4 688
b5c19bd7 689 if (out_capture) {
dd2155a4 690
b5c19bd7
DM
691 /* our ? */
692 if ((SvFLAGS(*out_name_sv) & SVpad_OUR)) {
693 *out_capture = Nullsv;
694 return offset;
695 }
ee6cee0c 696
b5c19bd7
DM
697 /* trying to capture from an anon prototype? */
698 if (CvCOMPILED(cv)
699 ? CvANON(cv) && CvCLONE(cv) && !CvCLONED(cv)
700 : *out_flags & PAD_FAKELEX_ANON)
701 {
702 if (warn && ckWARN(WARN_CLOSURE))
703 Perl_warner(aTHX_ packWARN(WARN_CLOSURE),
704 "Variable \"%s\" is not available", name);
705 *out_capture = Nullsv;
706 }
ee6cee0c 707
b5c19bd7
DM
708 /* real value */
709 else {
710 int newwarn = warn;
711 if (!CvCOMPILED(cv) && (*out_flags & PAD_FAKELEX_MULTI)
712 && warn && ckWARN(WARN_CLOSURE)) {
713 newwarn = 0;
714 Perl_warner(aTHX_ packWARN(WARN_CLOSURE),
715 "Variable \"%s\" will not stay shared", name);
716 }
dd2155a4 717
b5c19bd7
DM
718 if (fake_offset && CvANON(cv)
719 && CvCLONE(cv) &&!CvCLONED(cv))
720 {
721 SV *n;
722 /* not yet caught - look further up */
723 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
724 "Pad findlex cv=0x%"UVxf" chasing lex in outer pad\n",
725 PTR2UV(cv)));
726 n = *out_name_sv;
727 pad_findlex(name, CvOUTSIDE(cv), CvOUTSIDE_SEQ(cv),
728 newwarn, out_capture, out_name_sv, out_flags);
729 *out_name_sv = n;
730 return offset;
dd2155a4 731 }
b5c19bd7
DM
732
733 *out_capture = AvARRAY((AV*)AvARRAY(padlist)[
734 CvDEPTH(cv) ? CvDEPTH(cv) : 1])[offset];
735 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
736 "Pad findlex cv=0x%"UVxf" found lex=0x%"UVxf"\n",
19a5c512 737 PTR2UV(cv), PTR2UV(*out_capture)));
b5c19bd7
DM
738
739 if (SvPADSTALE(*out_capture)) {
740 if (ckWARN(WARN_CLOSURE))
ee6cee0c 741 Perl_warner(aTHX_ packWARN(WARN_CLOSURE),
b5c19bd7
DM
742 "Variable \"%s\" is not available", name);
743 *out_capture = Nullsv;
dd2155a4
DM
744 }
745 }
b5c19bd7
DM
746 if (!*out_capture) {
747 if (*name == '@')
748 *out_capture = sv_2mortal((SV*)newAV());
749 else if (*name == '%')
750 *out_capture = sv_2mortal((SV*)newHV());
751 else
752 *out_capture = sv_newmortal();
753 }
dd2155a4 754 }
b5c19bd7
DM
755
756 return offset;
ee6cee0c 757 }
b5c19bd7
DM
758 }
759
760 /* it's not in this pad - try above */
761
762 if (!CvOUTSIDE(cv))
763 return NOT_IN_PAD;
764
765 /* out_capture non-null means caller wants us to capture lex; in
71f882da 766 * addition we capture ourselves unless it's an ANON/format */
b5c19bd7 767 new_capturep = out_capture ? out_capture :
71f882da 768 CvLATE(cv) ? Null(SV**) : &new_capture;
b5c19bd7
DM
769
770 offset = pad_findlex(name, CvOUTSIDE(cv), CvOUTSIDE_SEQ(cv), 1,
771 new_capturep, out_name_sv, out_flags);
772 if (offset == NOT_IN_PAD)
773 return NOT_IN_PAD;
774
775 /* found in an outer CV. Add appropriate fake entry to this pad */
776
777 /* don't add new fake entries (via eval) to CVs that we have already
778 * finished compiling, or to undef CVs */
779 if (CvCOMPILED(cv) || !padlist)
780 return 0; /* this dummy (and invalid) value isnt used by the caller */
781
782 {
783 SV *new_namesv;
784 AV *ocomppad_name = PL_comppad_name;
785 PAD *ocomppad = PL_comppad;
786 PL_comppad_name = (AV*)AvARRAY(padlist)[0];
787 PL_comppad = (AV*)AvARRAY(padlist)[1];
788 PL_curpad = AvARRAY(PL_comppad);
789
790 new_offset = pad_add_name(
791 SvPVX(*out_name_sv),
792 (SvFLAGS(*out_name_sv) & SVpad_TYPED)
793 ? SvSTASH(*out_name_sv) : Nullhv,
794 (SvFLAGS(*out_name_sv) & SVpad_OUR)
795 ? GvSTASH(*out_name_sv) : Nullhv,
796 1 /* fake */
797 );
798
799 new_namesv = AvARRAY(PL_comppad_name)[new_offset];
800 SvIVX(new_namesv) = *out_flags;
801
802 SvNVX(new_namesv) = (NV)0;
803 if (SvFLAGS(new_namesv) & SVpad_OUR) {
804 /* do nothing */
805 }
71f882da 806 else if (CvLATE(cv)) {
b5c19bd7
DM
807 /* delayed creation - just note the offset within parent pad */
808 SvNVX(new_namesv) = (NV)offset;
809 CvCLONE_on(cv);
810 }
811 else {
812 /* immediate creation - capture outer value right now */
813 av_store(PL_comppad, new_offset, SvREFCNT_inc(*new_capturep));
814 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
815 "Pad findlex cv=0x%"UVxf" saved captured sv 0x%"UVxf" at offset %ld\n",
816 PTR2UV(cv), PTR2UV(*new_capturep), (long)new_offset));
dd2155a4 817 }
b5c19bd7
DM
818 *out_name_sv = new_namesv;
819 *out_flags = SvIVX(new_namesv);
820
821 PL_comppad_name = ocomppad_name;
822 PL_comppad = ocomppad;
823 PL_curpad = ocomppad ? AvARRAY(ocomppad) : Null(SV **);
dd2155a4 824 }
b5c19bd7 825 return new_offset;
dd2155a4
DM
826}
827
b5c19bd7 828
dd2155a4
DM
829/*
830=for apidoc pad_sv
831
832Get the value at offset po in the current pad.
833Use macro PAD_SV instead of calling this function directly.
834
835=cut
836*/
837
838
839SV *
840Perl_pad_sv(pTHX_ PADOFFSET po)
841{
f3548bdc 842 ASSERT_CURPAD_ACTIVE("pad_sv");
dd2155a4 843
dd2155a4
DM
844 if (!po)
845 Perl_croak(aTHX_ "panic: pad_sv po");
dd2155a4
DM
846 DEBUG_X(PerlIO_printf(Perl_debug_log,
847 "Pad 0x%"UVxf"[0x%"UVxf"] sv: %ld sv=0x%"UVxf"\n",
f3548bdc 848 PTR2UV(PL_comppad), PTR2UV(PL_curpad), (long)po, PTR2UV(PL_curpad[po]))
dd2155a4
DM
849 );
850 return PL_curpad[po];
851}
852
853
854/*
855=for apidoc pad_setsv
856
857Set the entry at offset po in the current pad to sv.
858Use the macro PAD_SETSV() rather than calling this function directly.
859
860=cut
861*/
862
863#ifdef DEBUGGING
864void
865Perl_pad_setsv(pTHX_ PADOFFSET po, SV* sv)
866{
f3548bdc 867 ASSERT_CURPAD_ACTIVE("pad_setsv");
dd2155a4
DM
868
869 DEBUG_X(PerlIO_printf(Perl_debug_log,
870 "Pad 0x%"UVxf"[0x%"UVxf"] setsv: %ld sv=0x%"UVxf"\n",
f3548bdc 871 PTR2UV(PL_comppad), PTR2UV(PL_curpad), (long)po, PTR2UV(sv))
dd2155a4
DM
872 );
873 PL_curpad[po] = sv;
874}
875#endif
876
877
878
879/*
880=for apidoc pad_block_start
881
882Update the pad compilation state variables on entry to a new block
883
884=cut
885*/
886
887/* XXX DAPM perhaps:
888 * - integrate this in general state-saving routine ???
889 * - combine with the state-saving going on in pad_new ???
890 * - introduce a new SAVE type that does all this in one go ?
891 */
892
893void
894Perl_pad_block_start(pTHX_ int full)
895{
f3548bdc 896 ASSERT_CURPAD_ACTIVE("pad_block_start");
dd2155a4
DM
897 SAVEI32(PL_comppad_name_floor);
898 PL_comppad_name_floor = AvFILLp(PL_comppad_name);
899 if (full)
900 PL_comppad_name_fill = PL_comppad_name_floor;
901 if (PL_comppad_name_floor < 0)
902 PL_comppad_name_floor = 0;
903 SAVEI32(PL_min_intro_pending);
904 SAVEI32(PL_max_intro_pending);
905 PL_min_intro_pending = 0;
906 SAVEI32(PL_comppad_name_fill);
907 SAVEI32(PL_padix_floor);
908 PL_padix_floor = PL_padix;
909 PL_pad_reset_pending = FALSE;
910}
911
912
913/*
914=for apidoc intro_my
915
916"Introduce" my variables to visible status.
917
918=cut
919*/
920
921U32
922Perl_intro_my(pTHX)
923{
924 SV **svp;
925 SV *sv;
926 I32 i;
927
f3548bdc 928 ASSERT_CURPAD_ACTIVE("intro_my");
dd2155a4
DM
929 if (! PL_min_intro_pending)
930 return PL_cop_seqmax;
931
932 svp = AvARRAY(PL_comppad_name);
933 for (i = PL_min_intro_pending; i <= PL_max_intro_pending; i++) {
ee6cee0c
DM
934 if ((sv = svp[i]) && sv != &PL_sv_undef
935 && !SvFAKE(sv) && !SvIVX(sv))
936 {
dd2155a4
DM
937 SvIVX(sv) = PAD_MAX; /* Don't know scope end yet. */
938 SvNVX(sv) = (NV)PL_cop_seqmax;
939 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
b5c19bd7 940 "Pad intromy: %ld \"%s\", (%ld,%ld)\n",
dd2155a4 941 (long)i, SvPVX(sv),
4cf4a199 942 (long)U_32(SvNVX(sv)), (long)SvIVX(sv))
dd2155a4
DM
943 );
944 }
945 }
946 PL_min_intro_pending = 0;
947 PL_comppad_name_fill = PL_max_intro_pending; /* Needn't search higher */
948 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
949 "Pad intromy: seq -> %ld\n", (long)(PL_cop_seqmax+1)));
950
951 return PL_cop_seqmax++;
952}
953
954/*
955=for apidoc pad_leavemy
956
957Cleanup at end of scope during compilation: set the max seq number for
958lexicals in this scope and warn of any lexicals that never got introduced.
959
960=cut
961*/
962
963void
964Perl_pad_leavemy(pTHX)
965{
966 I32 off;
967 SV **svp = AvARRAY(PL_comppad_name);
968 SV *sv;
969
970 PL_pad_reset_pending = FALSE;
971
f3548bdc 972 ASSERT_CURPAD_ACTIVE("pad_leavemy");
dd2155a4
DM
973 if (PL_min_intro_pending && PL_comppad_name_fill < PL_min_intro_pending) {
974 for (off = PL_max_intro_pending; off >= PL_min_intro_pending; off--) {
ee6cee0c
DM
975 if ((sv = svp[off]) && sv != &PL_sv_undef
976 && !SvFAKE(sv) && ckWARN_d(WARN_INTERNAL))
dd2155a4 977 Perl_warner(aTHX_ packWARN(WARN_INTERNAL),
35c1215d 978 "%"SVf" never introduced", sv);
dd2155a4
DM
979 }
980 }
981 /* "Deintroduce" my variables that are leaving with this scope. */
982 for (off = AvFILLp(PL_comppad_name); off > PL_comppad_name_fill; off--) {
ee6cee0c
DM
983 if ((sv = svp[off]) && sv != &PL_sv_undef
984 && !SvFAKE(sv) && SvIVX(sv) == PAD_MAX)
985 {
dd2155a4
DM
986 SvIVX(sv) = PL_cop_seqmax;
987 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
b5c19bd7 988 "Pad leavemy: %ld \"%s\", (%ld,%ld)\n",
dd2155a4 989 (long)off, SvPVX(sv),
4cf4a199 990 (long)U_32(SvNVX(sv)), (long)SvIVX(sv))
dd2155a4
DM
991 );
992 }
993 }
994 PL_cop_seqmax++;
995 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
996 "Pad leavemy: seq = %ld\n", (long)PL_cop_seqmax));
997}
998
999
1000/*
1001=for apidoc pad_swipe
1002
1003Abandon the tmp in the current pad at offset po and replace with a
1004new one.
1005
1006=cut
1007*/
1008
1009void
1010Perl_pad_swipe(pTHX_ PADOFFSET po, bool refadjust)
1011{
f3548bdc 1012 ASSERT_CURPAD_LEGAL("pad_swipe");
dd2155a4
DM
1013 if (!PL_curpad)
1014 return;
1015 if (AvARRAY(PL_comppad) != PL_curpad)
1016 Perl_croak(aTHX_ "panic: pad_swipe curpad");
1017 if (!po)
1018 Perl_croak(aTHX_ "panic: pad_swipe po");
1019
1020 DEBUG_X(PerlIO_printf(Perl_debug_log,
1021 "Pad 0x%"UVxf"[0x%"UVxf"] swipe: %ld\n",
1022 PTR2UV(PL_comppad), PTR2UV(PL_curpad), (long)po));
1023
1024 if (PL_curpad[po])
1025 SvPADTMP_off(PL_curpad[po]);
1026 if (refadjust)
1027 SvREFCNT_dec(PL_curpad[po]);
1028
1029 PL_curpad[po] = NEWSV(1107,0);
1030 SvPADTMP_on(PL_curpad[po]);
1031 if ((I32)po < PL_padix)
1032 PL_padix = po - 1;
1033}
1034
1035
1036/*
1037=for apidoc pad_reset
1038
1039Mark all the current temporaries for reuse
1040
1041=cut
1042*/
1043
1044/* XXX pad_reset() is currently disabled because it results in serious bugs.
1045 * It causes pad temp TARGs to be shared between OPs. Since TARGs are pushed
1046 * on the stack by OPs that use them, there are several ways to get an alias
1047 * to a shared TARG. Such an alias will change randomly and unpredictably.
1048 * We avoid doing this until we can think of a Better Way.
1049 * GSAR 97-10-29 */
1050void
1051Perl_pad_reset(pTHX)
1052{
1053#ifdef USE_BROKEN_PAD_RESET
1054 register I32 po;
1055
1056 if (AvARRAY(PL_comppad) != PL_curpad)
1057 Perl_croak(aTHX_ "panic: pad_reset curpad");
1058
1059 DEBUG_X(PerlIO_printf(Perl_debug_log,
1060 "Pad 0x%"UVxf"[0x%"UVxf"] reset: padix %ld -> %ld",
1061 PTR2UV(PL_comppad), PTR2UV(PL_curpad),
1062 (long)PL_padix, (long)PL_padix_floor
1063 )
1064 );
1065
1066 if (!PL_tainting) { /* Can't mix tainted and non-tainted temporaries. */
1067 for (po = AvMAX(PL_comppad); po > PL_padix_floor; po--) {
1068 if (PL_curpad[po] && !SvIMMORTAL(PL_curpad[po]))
1069 SvPADTMP_off(PL_curpad[po]);
1070 }
1071 PL_padix = PL_padix_floor;
1072 }
1073#endif
1074 PL_pad_reset_pending = FALSE;
1075}
1076
1077
1078/*
1079=for apidoc pad_tidy
1080
1081Tidy up a pad after we've finished compiling it:
1082 * remove most stuff from the pads of anonsub prototypes;
1083 * give it a @_;
1084 * mark tmps as such.
1085
1086=cut
1087*/
1088
1089/* XXX DAPM surely most of this stuff should be done properly
1090 * at the right time beforehand, rather than going around afterwards
1091 * cleaning up our mistakes ???
1092 */
1093
1094void
1095Perl_pad_tidy(pTHX_ padtidy_type type)
1096{
1097 PADOFFSET ix;
b5c19bd7 1098 CV *cv;
dd2155a4 1099
f3548bdc 1100 ASSERT_CURPAD_ACTIVE("pad_tidy");
b5c19bd7
DM
1101
1102 /* If this CV has had any 'eval-capable' ops planted in it
1103 * (ie it contains eval '...', //ee, /$var/ or /(?{..})/), Then any
1104 * anon prototypes in the chain of CVs should be marked as cloneable,
1105 * so that for example the eval's CV in C<< sub { eval '$x' } >> gets
1106 * the right CvOUTSIDE.
1107 * If running with -d, *any* sub may potentially have an eval
1108 * excuted within it.
1109 */
1110
1111 if (PL_cv_has_eval || PL_perldb) {
1112 for (cv = PL_compcv ;cv; cv = CvOUTSIDE(cv)) {
1113 if (cv != PL_compcv && CvCOMPILED(cv))
1114 break; /* no need to mark already-compiled code */
1115 if (CvANON(cv)) {
1116 DEBUG_Xv(PerlIO_printf(Perl_debug_log,
1117 "Pad clone on cv=0x%"UVxf"\n", PTR2UV(cv)));
1118 CvCLONE_on(cv);
1119 }
1120 }
1121 }
1122
dd2155a4
DM
1123 /* extend curpad to match namepad */
1124 if (AvFILLp(PL_comppad_name) < AvFILLp(PL_comppad))
1125 av_store(PL_comppad_name, AvFILLp(PL_comppad), Nullsv);
1126
1127 if (type == padtidy_SUBCLONE) {
1128 SV **namep = AvARRAY(PL_comppad_name);
b5c19bd7 1129
dd2155a4
DM
1130 for (ix = AvFILLp(PL_comppad); ix > 0; ix--) {
1131 SV *namesv;
1132
1133 if (SvIMMORTAL(PL_curpad[ix]) || IS_PADGV(PL_curpad[ix]) || IS_PADCONST(PL_curpad[ix]))
1134 continue;
1135 /*
1136 * The only things that a clonable function needs in its
b5c19bd7 1137 * pad are anonymous subs.
dd2155a4
DM
1138 * The rest are created anew during cloning.
1139 */
1140 if (!((namesv = namep[ix]) != Nullsv &&
1141 namesv != &PL_sv_undef &&
b5c19bd7 1142 *SvPVX(namesv) == '&'))
dd2155a4
DM
1143 {
1144 SvREFCNT_dec(PL_curpad[ix]);
1145 PL_curpad[ix] = Nullsv;
1146 }
1147 }
1148 }
1149 else if (type == padtidy_SUB) {
1150 /* XXX DAPM this same bit of code keeps appearing !!! Rationalise? */
1151 AV *av = newAV(); /* Will be @_ */
1152 av_extend(av, 0);
1153 av_store(PL_comppad, 0, (SV*)av);
1154 AvFLAGS(av) = AVf_REIFY;
1155 }
1156
1157 /* XXX DAPM rationalise these two similar branches */
1158
1159 if (type == padtidy_SUB) {
1160 for (ix = AvFILLp(PL_comppad); ix > 0; ix--) {
1161 if (SvIMMORTAL(PL_curpad[ix]) || IS_PADGV(PL_curpad[ix]) || IS_PADCONST(PL_curpad[ix]))
1162 continue;
1163 if (!SvPADMY(PL_curpad[ix]))
1164 SvPADTMP_on(PL_curpad[ix]);
1165 }
1166 }
1167 else if (type == padtidy_FORMAT) {
1168 for (ix = AvFILLp(PL_comppad); ix > 0; ix--) {
1169 if (!SvPADMY(PL_curpad[ix]) && !SvIMMORTAL(PL_curpad[ix]))
1170 SvPADTMP_on(PL_curpad[ix]);
1171 }
1172 }
f3548bdc 1173 PL_curpad = AvARRAY(PL_comppad);
dd2155a4
DM
1174}
1175
1176
1177/*
1178=for apidoc pad_free
1179
1180Free the SV at offet po in the current pad.
1181
1182=cut
1183*/
1184
1185/* XXX DAPM integrate with pad_swipe ???? */
1186void
1187Perl_pad_free(pTHX_ PADOFFSET po)
1188{
f3548bdc 1189 ASSERT_CURPAD_LEGAL("pad_free");
dd2155a4
DM
1190 if (!PL_curpad)
1191 return;
1192 if (AvARRAY(PL_comppad) != PL_curpad)
1193 Perl_croak(aTHX_ "panic: pad_free curpad");
1194 if (!po)
1195 Perl_croak(aTHX_ "panic: pad_free po");
1196
1197 DEBUG_X(PerlIO_printf(Perl_debug_log,
1198 "Pad 0x%"UVxf"[0x%"UVxf"] free: %ld\n",
1199 PTR2UV(PL_comppad), PTR2UV(PL_curpad), (long)po)
1200 );
1201
1202 if (PL_curpad[po] && PL_curpad[po] != &PL_sv_undef) {
1203 SvPADTMP_off(PL_curpad[po]);
1204#ifdef USE_ITHREADS
7e736055
HS
1205 /* SV could be a shared hash key (eg bugid #19022) */
1206 if (
dd2155a4 1207#ifdef PERL_COPY_ON_WRITE
7e736055
HS
1208 !SvIsCOW(PL_curpad[po])
1209#else
1210 !SvFAKE(PL_curpad[po])
dd2155a4 1211#endif
7e736055 1212 )
dd2155a4 1213 SvREADONLY_off(PL_curpad[po]); /* could be a freed constant */
dd2155a4
DM
1214#endif
1215 }
1216 if ((I32)po < PL_padix)
1217 PL_padix = po - 1;
1218}
1219
1220
1221
1222/*
1223=for apidoc do_dump_pad
1224
1225Dump the contents of a padlist
1226
1227=cut
1228*/
1229
1230void
1231Perl_do_dump_pad(pTHX_ I32 level, PerlIO *file, PADLIST *padlist, int full)
1232{
1233 AV *pad_name;
1234 AV *pad;
1235 SV **pname;
1236 SV **ppad;
1237 SV *namesv;
1238 I32 ix;
1239
1240 if (!padlist) {
1241 return;
1242 }
1243 pad_name = (AV*)*av_fetch((AV*)padlist, 0, FALSE);
1244 pad = (AV*)*av_fetch((AV*)padlist, 1, FALSE);
1245 pname = AvARRAY(pad_name);
1246 ppad = AvARRAY(pad);
1247 Perl_dump_indent(aTHX_ level, file,
1248 "PADNAME = 0x%"UVxf"(0x%"UVxf") PAD = 0x%"UVxf"(0x%"UVxf")\n",
1249 PTR2UV(pad_name), PTR2UV(pname), PTR2UV(pad), PTR2UV(ppad)
1250 );
1251
1252 for (ix = 1; ix <= AvFILLp(pad_name); ix++) {
1253 namesv = pname[ix];
1254 if (namesv && namesv == &PL_sv_undef) {
1255 namesv = Nullsv;
1256 }
1257 if (namesv) {
ee6cee0c
DM
1258 if (SvFAKE(namesv))
1259 Perl_dump_indent(aTHX_ level+1, file,
b5c19bd7 1260 "%2d. 0x%"UVxf"<%lu> FAKE \"%s\" flags=0x%x index=%lu\n",
ee6cee0c
DM
1261 (int) ix,
1262 PTR2UV(ppad[ix]),
1263 (unsigned long) (ppad[ix] ? SvREFCNT(ppad[ix]) : 0),
b5c19bd7
DM
1264 SvPVX(namesv),
1265 (unsigned long)SvIVX(namesv),
1266 (unsigned long)SvNVX(namesv)
1267
ee6cee0c
DM
1268 );
1269 else
1270 Perl_dump_indent(aTHX_ level+1, file,
b5c19bd7 1271 "%2d. 0x%"UVxf"<%lu> (%ld,%ld) \"%s\"\n",
ee6cee0c
DM
1272 (int) ix,
1273 PTR2UV(ppad[ix]),
1274 (unsigned long) (ppad[ix] ? SvREFCNT(ppad[ix]) : 0),
4cf4a199 1275 (long)U_32(SvNVX(namesv)),
b5c19bd7 1276 (long)SvIVX(namesv),
e9d09c08 1277 SvPVX(namesv)
ee6cee0c 1278 );
dd2155a4
DM
1279 }
1280 else if (full) {
1281 Perl_dump_indent(aTHX_ level+1, file,
1282 "%2d. 0x%"UVxf"<%lu>\n",
1283 (int) ix,
1284 PTR2UV(ppad[ix]),
1285 (unsigned long) (ppad[ix] ? SvREFCNT(ppad[ix]) : 0)
1286 );
1287 }
1288 }
1289}
1290
1291
1292
1293/*
1294=for apidoc cv_dump
1295
1296dump the contents of a CV
1297
1298=cut
1299*/
1300
1301#ifdef DEBUGGING
1302STATIC void
1303S_cv_dump(pTHX_ CV *cv, char *title)
1304{
1305 CV *outside = CvOUTSIDE(cv);
1306 AV* padlist = CvPADLIST(cv);
1307
1308 PerlIO_printf(Perl_debug_log,
1309 " %s: CV=0x%"UVxf" (%s), OUTSIDE=0x%"UVxf" (%s)\n",
1310 title,
1311 PTR2UV(cv),
1312 (CvANON(cv) ? "ANON"
71f882da 1313 : (SvTYPE(cv) == SVt_PVFM) ? "FORMAT"
dd2155a4
DM
1314 : (cv == PL_main_cv) ? "MAIN"
1315 : CvUNIQUE(cv) ? "UNIQUE"
1316 : CvGV(cv) ? GvNAME(CvGV(cv)) : "UNDEFINED"),
1317 PTR2UV(outside),
1318 (!outside ? "null"
1319 : CvANON(outside) ? "ANON"
1320 : (outside == PL_main_cv) ? "MAIN"
1321 : CvUNIQUE(outside) ? "UNIQUE"
1322 : CvGV(outside) ? GvNAME(CvGV(outside)) : "UNDEFINED"));
1323
1324 PerlIO_printf(Perl_debug_log,
1325 " PADLIST = 0x%"UVxf"\n", PTR2UV(padlist));
1326 do_dump_pad(1, Perl_debug_log, padlist, 1);
1327}
1328#endif /* DEBUGGING */
1329
1330
1331
1332
1333
1334/*
1335=for apidoc cv_clone
1336
1337Clone a CV: make a new CV which points to the same code etc, but which
1338has a newly-created pad built by copying the prototype pad and capturing
1339any outer lexicals.
1340
1341=cut
1342*/
1343
1344CV *
1345Perl_cv_clone(pTHX_ CV *proto)
1346{
dd2155a4
DM
1347 I32 ix;
1348 AV* protopadlist = CvPADLIST(proto);
1349 AV* protopad_name = (AV*)*av_fetch(protopadlist, 0, FALSE);
1350 AV* protopad = (AV*)*av_fetch(protopadlist, 1, FALSE);
1351 SV** pname = AvARRAY(protopad_name);
1352 SV** ppad = AvARRAY(protopad);
1353 I32 fname = AvFILLp(protopad_name);
1354 I32 fpad = AvFILLp(protopad);
1355 AV* comppadlist;
1356 CV* cv;
b5c19bd7
DM
1357 SV** outpad;
1358 CV* outside;
71f882da 1359 long depth;
dd2155a4
DM
1360
1361 assert(!CvUNIQUE(proto));
1362
71f882da
DM
1363 /* Since cloneable anon subs can be nested, CvOUTSIDE may point
1364 * to a prototype; we instead want the cloned parent who called us.
1365 * Note that in general for formats, CvOUTSIDE != find_runcv */
1366
1367 outside = CvOUTSIDE(proto);
1368 if (outside && CvCLONE(outside) && ! CvCLONED(outside))
1369 outside = find_runcv(NULL);
1370 depth = CvDEPTH(outside);
1371 assert(depth || SvTYPE(proto) == SVt_PVFM);
1372 if (!depth)
1373 depth = 1;
b5c19bd7
DM
1374 assert(CvPADLIST(outside));
1375
dd2155a4
DM
1376 ENTER;
1377 SAVESPTR(PL_compcv);
1378
1379 cv = PL_compcv = (CV*)NEWSV(1104, 0);
1380 sv_upgrade((SV *)cv, SvTYPE(proto));
7dafbf52 1381 CvFLAGS(cv) = CvFLAGS(proto) & ~(CVf_CLONE|CVf_WEAKOUTSIDE);
dd2155a4
DM
1382 CvCLONED_on(cv);
1383
dd2155a4
DM
1384#ifdef USE_ITHREADS
1385 CvFILE(cv) = CvXSUB(proto) ? CvFILE(proto)
1386 : savepv(CvFILE(proto));
1387#else
1388 CvFILE(cv) = CvFILE(proto);
1389#endif
1390 CvGV(cv) = CvGV(proto);
1391 CvSTASH(cv) = CvSTASH(proto);
1392 CvROOT(cv) = OpREFCNT_inc(CvROOT(proto));
1393 CvSTART(cv) = CvSTART(proto);
b5c19bd7
DM
1394 CvOUTSIDE(cv) = (CV*)SvREFCNT_inc(outside);
1395 CvOUTSIDE_SEQ(cv) = CvOUTSIDE_SEQ(proto);
dd2155a4
DM
1396
1397 if (SvPOK(proto))
1398 sv_setpvn((SV*)cv, SvPVX(proto), SvCUR(proto));
1399
1400 CvPADLIST(cv) = comppadlist = pad_new(padnew_CLONE|padnew_SAVE);
1401
b5c19bd7 1402 av_fill(PL_comppad, fpad);
dd2155a4
DM
1403 for (ix = fname; ix >= 0; ix--)
1404 av_store(PL_comppad_name, ix, SvREFCNT_inc(pname[ix]));
1405
dd2155a4
DM
1406 PL_curpad = AvARRAY(PL_comppad);
1407
71f882da 1408 outpad = AvARRAY(AvARRAY(CvPADLIST(outside))[depth]);
b5c19bd7 1409
dd2155a4
DM
1410 for (ix = fpad; ix > 0; ix--) {
1411 SV* namesv = (ix <= fname) ? pname[ix] : Nullsv;
71f882da
DM
1412 SV *sv = Nullsv;
1413 if (namesv && namesv != &PL_sv_undef) { /* lexical */
b5c19bd7 1414 if (SvFAKE(namesv)) { /* lexical from outside? */
71f882da
DM
1415 sv = outpad[(I32)SvNVX(namesv)];
1416 assert(sv);
1417 /* formats may have an inactive parent */
1418 if (SvTYPE(proto) == SVt_PVFM && SvPADSTALE(sv)) {
1419 if (ckWARN(WARN_CLOSURE))
1420 Perl_warner(aTHX_ packWARN(WARN_CLOSURE),
1421 "Variable \"%s\" is not available", SvPVX(namesv));
1422 sv = Nullsv;
1423 }
1424 else {
1425 assert(!SvPADSTALE(sv));
1426 sv = SvREFCNT_inc(sv);
1427 }
dd2155a4 1428 }
71f882da 1429 if (!sv) {
b5c19bd7
DM
1430 char *name = SvPVX(namesv);
1431 if (*name == '&')
dd2155a4 1432 sv = SvREFCNT_inc(ppad[ix]);
dd2155a4
DM
1433 else if (*name == '@')
1434 sv = (SV*)newAV();
1435 else if (*name == '%')
1436 sv = (SV*)newHV();
1437 else
1438 sv = NEWSV(0, 0);
235cc2e3 1439 SvPADMY_on(sv);
dd2155a4
DM
1440 }
1441 }
1442 else if (IS_PADGV(ppad[ix]) || IS_PADCONST(ppad[ix])) {
71f882da 1443 sv = SvREFCNT_inc(ppad[ix]);
dd2155a4
DM
1444 }
1445 else {
b5c19bd7 1446 sv = NEWSV(0, 0);
dd2155a4 1447 SvPADTMP_on(sv);
dd2155a4 1448 }
71f882da 1449 PL_curpad[ix] = sv;
dd2155a4
DM
1450 }
1451
dd2155a4
DM
1452 DEBUG_Xv(
1453 PerlIO_printf(Perl_debug_log, "\nPad CV clone\n");
1454 cv_dump(outside, "Outside");
1455 cv_dump(proto, "Proto");
1456 cv_dump(cv, "To");
1457 );
1458
1459 LEAVE;
1460
1461 if (CvCONST(cv)) {
b5c19bd7
DM
1462 /* Constant sub () { $x } closing over $x - see lib/constant.pm:
1463 * The prototype was marked as a candiate for const-ization,
1464 * so try to grab the current const value, and if successful,
1465 * turn into a const sub:
1466 */
dd2155a4 1467 SV* const_sv = op_const_sv(CvSTART(cv), cv);
b5c19bd7
DM
1468 if (const_sv) {
1469 SvREFCNT_dec(cv);
1470 cv = newCONSTSUB(CvSTASH(proto), 0, const_sv);
1471 }
1472 else {
1473 CvCONST_off(cv);
1474 }
dd2155a4
DM
1475 }
1476
1477 return cv;
1478}
1479
1480
1481/*
1482=for apidoc pad_fixup_inner_anons
1483
1484For any anon CVs in the pad, change CvOUTSIDE of that CV from
7dafbf52
DM
1485old_cv to new_cv if necessary. Needed when a newly-compiled CV has to be
1486moved to a pre-existing CV struct.
dd2155a4
DM
1487
1488=cut
1489*/
1490
1491void
1492Perl_pad_fixup_inner_anons(pTHX_ PADLIST *padlist, CV *old_cv, CV *new_cv)
1493{
1494 I32 ix;
1495 AV *comppad_name = (AV*)AvARRAY(padlist)[0];
1496 AV *comppad = (AV*)AvARRAY(padlist)[1];
1497 SV **namepad = AvARRAY(comppad_name);
1498 SV **curpad = AvARRAY(comppad);
1499 for (ix = AvFILLp(comppad_name); ix > 0; ix--) {
1500 SV *namesv = namepad[ix];
1501 if (namesv && namesv != &PL_sv_undef
1502 && *SvPVX(namesv) == '&')
1503 {
1504 CV *innercv = (CV*)curpad[ix];
7dafbf52
DM
1505 assert(CvWEAKOUTSIDE(innercv));
1506 assert(CvOUTSIDE(innercv) == old_cv);
1507 CvOUTSIDE(innercv) = new_cv;
dd2155a4
DM
1508 }
1509 }
1510}
1511
7dafbf52 1512
dd2155a4
DM
1513/*
1514=for apidoc pad_push
1515
1516Push a new pad frame onto the padlist, unless there's already a pad at
1517this depth, in which case don't bother creating a new one.
1518If has_args is true, give the new pad an @_ in slot zero.
1519
1520=cut
1521*/
1522
1523void
1524Perl_pad_push(pTHX_ PADLIST *padlist, int depth, int has_args)
1525{
1526 if (depth <= AvFILLp(padlist))
1527 return;
1528
1529 {
1530 SV** svp = AvARRAY(padlist);
1531 AV *newpad = newAV();
1532 SV **oldpad = AvARRAY(svp[depth-1]);
1533 I32 ix = AvFILLp((AV*)svp[1]);
1534 I32 names_fill = AvFILLp((AV*)svp[0]);
1535 SV** names = AvARRAY(svp[0]);
1536 SV* sv;
1537 for ( ;ix > 0; ix--) {
1538 if (names_fill >= ix && names[ix] != &PL_sv_undef) {
1539 char *name = SvPVX(names[ix]);
1540 if ((SvFLAGS(names[ix]) & SVf_FAKE) || *name == '&') {
1541 /* outer lexical or anon code */
1542 av_store(newpad, ix, SvREFCNT_inc(oldpad[ix]));
1543 }
1544 else { /* our own lexical */
1545 if (*name == '@')
1546 av_store(newpad, ix, sv = (SV*)newAV());
1547 else if (*name == '%')
1548 av_store(newpad, ix, sv = (SV*)newHV());
1549 else
1550 av_store(newpad, ix, sv = NEWSV(0, 0));
1551 SvPADMY_on(sv);
1552 }
1553 }
1554 else if (IS_PADGV(oldpad[ix]) || IS_PADCONST(oldpad[ix])) {
1555 av_store(newpad, ix, sv = SvREFCNT_inc(oldpad[ix]));
1556 }
1557 else {
1558 /* save temporaries on recursion? */
1559 av_store(newpad, ix, sv = NEWSV(0, 0));
1560 SvPADTMP_on(sv);
1561 }
1562 }
1563 if (has_args) {
1564 AV* av = newAV();
1565 av_extend(av, 0);
1566 av_store(newpad, 0, (SV*)av);
1567 AvFLAGS(av) = AVf_REIFY;
1568 }
1569 av_store(padlist, depth, (SV*)newpad);
1570 AvFILLp(padlist) = depth;
1571 }
1572}