3 * Copyright (C) 2002, 2003, 2005, 2006, 2007, 2008,
4 * 2009, 2010, 2011 by Larry Wall and others
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
9 * This file defines the types and macros associated with the API for
10 * manipulating scratchpads, which are used by perl to store lexical
11 * variables, op targets and constants.
14 /* offsets within a pad */
16 typedef SSize_t PADOFFSET; /* signed so that -1 is a valid value */
17 #define NOT_IN_PAD ((PADOFFSET) -1)
19 /* B.xs expects the first members of these two structs to line up
20 (xpadl_max with xpadnl_fill).
24 SSize_t xpadl_max; /* max index for which array has space */
26 PAD ** xpadlarr_alloc; /* Pointer to beginning of array of AVs.
27 Note that a 'padnamelist *' is stored
28 in the 0 index of the AV. */
31 PAD * pad_1; /* this slice of PAD * array always alloced */
32 PAD * pad_2; /* maybe unalloced */
33 } * xpadlarr_dbg; /* for use with a C debugger only */
35 U32 xpadl_id; /* Semi-unique ID, shared between clones */
36 U32 xpadl_outid; /* ID of outer pad */
40 SSize_t xpadnl_fill; /* max index in use */
41 PADNAME ** xpadnl_alloc; /* pointer to beginning of array */
42 SSize_t xpadnl_max; /* max index for which array has space */
43 PADOFFSET xpadnl_max_named; /* highest index with len > 0 */
47 /* PERL_PADNAME_MINIMAL uses less memory, but on some platforms
48 PERL_PADNAME_ALIGNED may be faster, so platform-specific hints can
49 define one or the other. */
50 #if defined(PERL_PADNAME_MINIMAL) && defined (PERL_PADNAME_ALIGNED)
51 # error PERL_PADNAME_MINIMAL and PERL_PADNAME_ALIGNED are exclusive
54 #if !defined(PERL_PADNAME_MINIMAL) && !defined(PERL_PADNAME_ALIGNED)
55 # define PERL_PADNAME_MINIMAL
58 struct padname_fieldinfo;
60 #define _PADNAME_BASE \
62 HV * xpadn_ourstash; \
64 HV * xpadn_typestash; \
67 struct padname_fieldinfo *xpadn_fieldinfo; \
79 struct padname_with_str {
80 #ifdef PERL_PADNAME_MINIMAL
83 struct padname xpadn_padname;
90 #define PADNAME_FROM_PV(s) \
91 ((PADNAME *)((s) - STRUCT_OFFSET(struct padname_with_str, xpadn_str)))
93 /* Most padnames are not field names. Keep all the field-related info in its
94 * own substructure, stored in ->xpadn_fieldinfo.
96 struct padname_fieldinfo {
97 PADOFFSET fieldix; /* index of this field within ObjectFIELDS() array */
98 HV *fieldstash; /* original class package which added this field */
99 OP *defop; /* optree fragment for defaulting expression */
103 /* a value that PL_cop_seqmax is guaranteed never to be,
104 * flagging that a lexical is being introduced, or has not yet left scope
106 #define PERL_PADSEQ_INTRO U32_MAX
107 #define COP_SEQMAX_INC \
109 (void)(PL_cop_seqmax == PERL_PADSEQ_INTRO && PL_cop_seqmax++))
112 /* B.xs needs these for the benefit of B::Deparse */
113 /* Low range end is exclusive (valid from the cop seq after this one) */
114 /* High range end is inclusive (valid up to this cop seq) */
116 #define COP_SEQ_RANGE_LOW(pn) (pn)->xpadn_low
117 #define COP_SEQ_RANGE_HIGH(pn) (pn)->xpadn_high
118 #define PARENT_PAD_INDEX(pn) (pn)->xpadn_low
119 #define PARENT_FAKELEX_FLAGS(pn) (pn)->xpadn_high
121 /* Flags set in the SvIVX field of FAKE namesvs */
123 #define PAD_FAKELEX_ANON 1 /* the lex is declared in an ANON, or ... */
124 #define PAD_FAKELEX_MULTI 2 /* the lex can be instantiated multiple times */
126 /* flags for the pad_new() function */
128 #define padnew_CLONE 1 /* this pad is for a cloned CV */
129 #define padnew_SAVE 2 /* save old globals */
130 #define padnew_SAVESUB 4 /* also save extra stuff for start of sub */
132 /* values for the pad_tidy() function */
135 padtidy_SUB, /* tidy up a pad for a sub, */
136 padtidy_SUBCLONE, /* a cloned sub, */
137 padtidy_FORMAT /* or a format */
140 /* flags for pad_add_name_pvn. */
142 #define padadd_OUR 0x01 /* our declaration. */
143 #define padadd_STATE 0x02 /* state declaration. */
144 #define padadd_NO_DUP_CHECK 0x04 /* skip warning on dups. */
145 #define padadd_STALEOK 0x08 /* allow stale lexical in active
146 * sub, but only one level up */
147 #define padadd_FIELD 0x10 /* set PADNAMEt_FIELD */
148 #define padfind_FIELD_OK 0x20 /* pad_findlex is permitted to see fields */
150 /* ASSERT_CURPAD_LEGAL and ASSERT_CURPAD_ACTIVE respectively determine
151 * whether PL_comppad and PL_curpad are consistent and whether they have
154 # define pad_peg(label)
157 # define ASSERT_CURPAD_LEGAL(label) \
159 if (PL_comppad ? (AvARRAY(PL_comppad) != PL_curpad) : (PL_curpad != 0)) \
160 Perl_croak(aTHX_ "panic: illegal pad in %s: 0x%" UVxf "[0x%" UVxf "]",\
161 label, PTR2UV(PL_comppad), PTR2UV(PL_curpad));
164 # define ASSERT_CURPAD_ACTIVE(label) \
166 if (!PL_comppad || (AvARRAY(PL_comppad) != PL_curpad)) \
167 Perl_croak(aTHX_ "panic: invalid pad in %s: 0x%" UVxf "[0x%" UVxf "]",\
168 label, PTR2UV(PL_comppad), PTR2UV(PL_curpad));
170 # define ASSERT_CURPAD_LEGAL(label)
171 # define ASSERT_CURPAD_ACTIVE(label)
176 /* Note: the following three macros are actually defined in scope.h, but
177 * they are documented here for completeness, since they directly or
178 * indirectly affect pads. */
181 =for apidoc m|void|SAVEPADSV |PADOFFSET po
182 Save a pad slot (used to restore after an iteration)
186 XXX DAPM it would make more sense to make the arg a PADOFFSET
188 =for apidoc m|void|SAVECLEARSV |SV **svp
189 Clear the pointed to pad value on scope exit. (i.e. the runtime action of
192 =for apidoc m|void|SAVECOMPPAD
193 save C<PL_comppad> and C<PL_curpad>
196 =for apidoc Amx|PAD **|PadlistARRAY|PADLIST * padlist
197 The C array of a padlist, containing the pads. Only subscript it with
198 numbers >= 1, as the 0th entry is not guaranteed to remain usable.
200 =for apidoc Amx|SSize_t|PadlistMAX|PADLIST * padlist
201 The index of the last allocated space in the padlist. Note that the last
202 pad may be in an earlier slot. Any entries following it will be C<NULL> in
205 =for apidoc Amx|PADNAMELIST *|PadlistNAMES|PADLIST * padlist
206 The names associated with pad entries.
208 =for apidoc Amx|PADNAME **|PadlistNAMESARRAY|PADLIST * padlist
209 The C array of pad names.
211 =for apidoc Amx|SSize_t|PadlistNAMESMAX|PADLIST * padlist
212 The index of the last pad name.
214 =for apidoc Amx|U32|PadlistREFCNT|PADLIST * padlist
215 The reference count of the padlist. Currently this is always 1.
217 =for apidoc Amx|PADNAME **|PadnamelistARRAY|PADNAMELIST * pnl
218 The C array of pad names.
220 =for apidoc Amx|SSize_t|PadnamelistMAX|PADNAMELIST * pnl
221 The index of the last pad name.
223 =for apidoc Amx|SSize_t|PadnamelistREFCNT|PADNAMELIST * pnl
224 The reference count of the pad name list.
226 =for apidoc Amx|void|PadnamelistREFCNT_dec|PADNAMELIST * pnl
227 Lowers the reference count of the pad name list.
229 =for apidoc Amx|SV **|PadARRAY|PAD * pad
230 The C array of pad entries.
232 =for apidoc Amx|SSize_t|PadMAX|PAD * pad
233 The index of the last pad entry.
235 =for apidoc Amx|char *|PadnamePV|PADNAME * pn
236 The name stored in the pad name struct. This returns C<NULL> for a target
239 =for apidoc Amx|STRLEN|PadnameLEN|PADNAME * pn
240 The length of the name.
242 =for apidoc Amx|bool|PadnameUTF8|PADNAME * pn
243 Whether PadnamePV is in UTF-8. Currently, this is always true.
245 =for apidoc Amx|SV *|PadnameSV|PADNAME * pn
246 Returns the pad name as a mortal SV.
248 =for apidoc m|bool|PadnameIsOUR|PADNAME * pn
249 Whether this is an "our" variable.
251 =for apidoc m|HV *|PadnameOURSTASH|PADNAME * pn
252 The stash in which this "our" variable was declared.
254 =for apidoc m|bool|PadnameOUTER|PADNAME * pn
255 Whether this entry belongs to an outer pad. Entries for which this is true
256 are often referred to as 'fake'.
258 =for apidoc m|bool|PadnameIsSTATE|PADNAME * pn
259 Whether this is a "state" variable.
261 =for apidoc m|bool|PadnameIsFIELD|PADNAME * pn
262 Whether this is a "field" variable. PADNAMEs where this is true will
263 have additional information available via C<PadnameFIELDINFO>.
265 =for apidoc m|HV *|PadnameTYPE|PADNAME * pn
266 The stash associated with a typed lexical. This returns the C<%Foo::> hash
269 =for apidoc Amx|SSize_t|PadnameREFCNT|PADNAME * pn
270 The reference count of the pad name.
272 =for apidoc Amx|PADNAME *|PadnameREFCNT_inc|PADNAME * pn
273 Increases the reference count of the pad name. Returns the pad name itself.
275 =for apidoc Amx|void|PadnameREFCNT_dec|PADNAME * pn
276 Lowers the reference count of the pad name.
279 =for apidoc m|SV *|PAD_SETSV |PADOFFSET po|SV* sv
280 Set the slot at offset C<po> in the current pad to C<sv>
282 =for apidoc m|SV *|PAD_SV |PADOFFSET po
283 Get the value at offset C<po> in the current pad
285 =for apidoc m|SV *|PAD_SVl |PADOFFSET po
286 Lightweight and lvalue version of C<PAD_SV>.
287 Get or set the value at offset C<po> in the current pad.
288 Unlike C<PAD_SV>, does not print diagnostics with -DX.
289 For internal use only.
291 =for apidoc m|SV *|PAD_BASE_SV |PADLIST padlist|PADOFFSET po
292 Get the value from slot C<po> in the base (DEPTH=1) pad of a padlist
294 =for apidoc m|void|PAD_SET_CUR |PADLIST padlist|I32 n
295 Set the current pad to be pad C<n> in the padlist, saving
296 the previous current pad. NB currently this macro expands to a string too
297 long for some compilers, so it's best to replace it with
300 PAD_SET_CUR_NOSAVE(padlist,n);
303 =for apidoc m|void|PAD_SET_CUR_NOSAVE |PADLIST padlist|I32 n
304 like PAD_SET_CUR, but without the save
306 =for apidoc m|void|PAD_SAVE_SETNULLPAD
307 Save the current pad then set it to null.
309 =for apidoc m|void|PAD_SAVE_LOCAL|PAD *opad|PAD *npad
310 Save the current pad to the local variable C<opad>, then make the
311 current pad equal to C<npad>
313 =for apidoc m|void|PAD_RESTORE_LOCAL|PAD *opad
314 Restore the old pad saved into the local variable C<opad> by C<PAD_SAVE_LOCAL()>
319 #define PadlistARRAY(pl) (pl)->xpadl_arr.xpadlarr_alloc
320 #define PadlistMAX(pl) (pl)->xpadl_max
321 #define PadlistNAMES(pl) *((PADNAMELIST **)PadlistARRAY(pl))
322 #define PadlistNAMESARRAY(pl) PadnamelistARRAY(PadlistNAMES(pl))
323 #define PadlistNAMESMAX(pl) PadnamelistMAX(PadlistNAMES(pl))
324 #define PadlistREFCNT(pl) 1 /* reserved for future use */
326 #define PadnamelistARRAY(pnl) (pnl)->xpadnl_alloc
327 #define PadnamelistMAX(pnl) (pnl)->xpadnl_fill
328 #define PadnamelistMAXNAMED(pnl) (pnl)->xpadnl_max_named
329 #define PadnamelistREFCNT(pnl) (pnl)->xpadnl_refcnt
330 #define PadnamelistREFCNT_dec(pnl) Perl_padnamelist_free(aTHX_ pnl)
332 #define PadARRAY(pad) AvARRAY(pad)
333 #define PadMAX(pad) AvFILLp(pad)
335 #define PadnamePV(pn) (pn)->xpadn_pv
336 #define PadnameLEN(pn) (pn)->xpadn_len
337 #define PadnameUTF8(pn) 1
338 #define PadnameSV(pn) \
339 newSVpvn_flags(PadnamePV(pn), PadnameLEN(pn), SVs_TEMP|SVf_UTF8)
340 #define PadnameFLAGS(pn) (pn)->xpadn_flags
341 #define PadnameIsOUR(pn) cBOOL((pn)->xpadn_ourstash)
342 #define PadnameOURSTASH(pn) (pn)->xpadn_ourstash
343 #define PadnameTYPE(pn) (pn)->xpadn_type_u.xpadn_typestash
344 #define PadnameHasTYPE(pn) cBOOL(PadnameTYPE(pn))
345 #define PadnamePROTOCV(pn) (pn)->xpadn_type_u.xpadn_protocv
346 #define PadnameREFCNT(pn) (pn)->xpadn_refcnt
347 #define PadnameREFCNT_inc(pn) Perl_padname_refcnt_inc(pn)
348 #define PadnameREFCNT_dec(pn) Perl_padname_free(aTHX_ pn)
349 #define PadnameOURSTASH_set(pn,s) (PadnameOURSTASH(pn) = (s))
350 #define PadnameTYPE_set(pn,s) (PadnameTYPE(pn) = (s))
351 #define PadnameFIELDINFO(pn) (pn)->xpadn_fieldinfo
352 #define PadnameOUTER(pn) (PadnameFLAGS(pn) & PADNAMEf_OUTER)
353 #define PadnameIsSTATE(pn) (PadnameFLAGS(pn) & PADNAMEf_STATE)
354 #define PadnameLVALUE(pn) (PadnameFLAGS(pn) & PADNAMEf_LVALUE)
355 #define PadnameIsFIELD(pn) (PadnameFLAGS(pn) & PADNAMEf_FIELD)
357 #define PadnameLVALUE_on(pn) (PadnameFLAGS(pn) |= PADNAMEf_LVALUE)
358 #define PadnameIsSTATE_on(pn) (PadnameFLAGS(pn) |= PADNAMEf_STATE)
360 #define PADNAMEf_OUTER 0x01 /* outer lexical var */
361 #define PADNAMEf_STATE 0x02 /* state var */
362 #define PADNAMEf_LVALUE 0x04 /* used as lvalue */
363 #define PADNAMEf_TYPED 0x08 /* for B; unused by core */
364 #define PADNAMEf_OUR 0x10 /* for B; unused by core */
365 #define PADNAMEf_FIELD 0x20 /* field var */
367 /* backward compatibility */
369 # define SvPAD_STATE PadnameIsSTATE
370 # define SvPAD_TYPED PadnameHasTYPE
371 # define SvPAD_OUR(pn) cBOOL(PadnameOURSTASH(pn))
372 # define SvPAD_STATE_on PadnameIsSTATE_on
373 # define SvPAD_TYPED_on(pn) (PadnameFLAGS(pn) |= PADNAMEf_TYPED)
374 # define SvPAD_OUR_on(pn) (PadnameFLAGS(pn) |= PADNAMEf_OUR)
375 # define SvOURSTASH PadnameOURSTASH
376 # define SvOURSTASH_set PadnameOURSTASH_set
377 # define SVpad_STATE PADNAMEf_STATE
378 # define SVpad_TYPED PADNAMEf_TYPED
379 # define SVpad_OUR PADNAMEf_OUR
380 # define PADNAMEt_OUTER PADNAMEf_OUTER
381 # define PADNAMEt_STATE PADNAMEf_STATE
382 # define PADNAMEt_LVALUE PADNAMEf_LVALUE
383 # define PADNAMEt_TYPED PADNAMEf_TYPED
384 # define PADNAMEt_OUR PADNAMEf_OUR
388 # define PAD_SV(po) pad_sv(po)
389 # define PAD_SETSV(po,sv) pad_setsv(po,sv)
391 # define PAD_SV(po) (PL_curpad[po])
392 # define PAD_SETSV(po,sv) PL_curpad[po] = (sv)
395 #define PAD_SVl(po) (PL_curpad[po])
397 #define PAD_BASE_SV(padlist, po) \
398 (PadlistARRAY(padlist)[1]) \
399 ? AvARRAY(MUTABLE_AV((PadlistARRAY(padlist)[1])))[po] \
403 #define PAD_SET_CUR_NOSAVE(padlist,nth) \
404 PL_comppad = (PAD*) (PadlistARRAY(padlist)[nth]); \
405 PL_curpad = AvARRAY(PL_comppad); \
406 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
407 "Pad 0x%" UVxf "[0x%" UVxf "] set_cur depth=%d\n", \
408 PTR2UV(PL_comppad), PTR2UV(PL_curpad), (int)(nth)));
411 #define PAD_SET_CUR(padlist,nth) \
413 PAD_SET_CUR_NOSAVE(padlist,nth);
416 #define PAD_SAVE_SETNULLPAD() SAVECOMPPAD(); \
417 PL_comppad = NULL; PL_curpad = NULL; \
418 DEBUG_Xv(PerlIO_printf(Perl_debug_log, "Pad set_null\n"));
420 #define PAD_SAVE_LOCAL(opad,npad) \
422 PL_comppad = (npad); \
423 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
424 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
425 "Pad 0x%" UVxf "[0x%" UVxf "] save_local\n", \
426 PTR2UV(PL_comppad), PTR2UV(PL_curpad)));
428 #define PAD_RESTORE_LOCAL(opad) \
429 assert(!opad || !SvIS_FREED(opad)); \
431 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
432 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
433 "Pad 0x%" UVxf "[0x%" UVxf "] restore_local\n", \
434 PTR2UV(PL_comppad), PTR2UV(PL_curpad)));
438 =for apidoc m|void|CX_CURPAD_SAVE|struct context
439 Save the current pad in the given context block structure.
441 =for apidoc m|SV *|CX_CURPAD_SV|struct context|PADOFFSET po
442 Access the SV at offset C<po> in the saved current pad in the given
443 context block structure (can be used as an lvalue).
448 #define CX_CURPAD_SAVE(block) (block).oldcomppad = PL_comppad
449 #define CX_CURPAD_SV(block,po) (AvARRAY(MUTABLE_AV(((block).oldcomppad)))[po])
453 =for apidoc m|U32|PAD_COMPNAME_FLAGS|PADOFFSET po
454 Return the flags for the current compiling pad name
455 at offset C<po>. Assumes a valid slot entry.
457 =for apidoc m|char *|PAD_COMPNAME_PV|PADOFFSET po
458 Return the name of the current compiling pad name
459 at offset C<po>. Assumes a valid slot entry.
461 =for apidoc m|HV *|PAD_COMPNAME_TYPE|PADOFFSET po
462 Return the type (stash) of the current compiling pad name at offset
463 C<po>. Must be a valid name. Returns null if not typed.
465 =for apidoc m|HV *|PAD_COMPNAME_OURSTASH|PADOFFSET po
466 Return the stash associated with an C<our> variable.
467 Assumes the slot entry is a valid C<our> lexical.
469 =for apidoc m|STRLEN|PAD_COMPNAME_GEN|PADOFFSET po
470 The generation number of the name at offset C<po> in the current
471 compiling pad (lvalue).
473 =for apidoc m|STRLEN|PAD_COMPNAME_GEN_set|PADOFFSET po|int gen
474 Sets the generation number of the name at offset C<po> in the current
475 ling pad (lvalue) to C<gen>.
480 #define PAD_COMPNAME(po) PAD_COMPNAME_SV(po)
481 #define PAD_COMPNAME_SV(po) (PadnamelistARRAY(PL_comppad_name)[(po)])
482 #define PAD_COMPNAME_FLAGS(po) PadnameFLAGS(PAD_COMPNAME(po))
483 #define PAD_COMPNAME_FLAGS_isOUR(po) PadnameIsOUR(PAD_COMPNAME_SV(po))
484 #define PAD_COMPNAME_PV(po) PadnamePV(PAD_COMPNAME(po))
486 #define PAD_COMPNAME_TYPE(po) PadnameTYPE(PAD_COMPNAME(po))
488 #define PAD_COMPNAME_OURSTASH(po) (PadnameOURSTASH(PAD_COMPNAME_SV(po)))
490 #define PAD_COMPNAME_GEN(po) \
491 ((STRLEN)PadnamelistARRAY(PL_comppad_name)[po]->xpadn_gen)
493 #define PAD_COMPNAME_GEN_set(po, gen) \
494 (PadnamelistARRAY(PL_comppad_name)[po]->xpadn_gen = (gen))
498 =for apidoc m|void|PAD_CLONE_VARS|PerlInterpreter *proto_perl|CLONE_PARAMS* param
499 Clone the state variables associated with running and compiling pads.
504 /* NB - we set PL_comppad to null unless it points at a value that
505 * has already been dup'ed, ie it points to part of an active padlist.
506 * Otherwise PL_comppad ends up being a leaked scalar in code like
508 * threads->create(sub { threads->create(sub {...} ) } );
509 * where the second thread dups the outer sub's comppad but not the
510 * sub's CV or padlist. */
512 #define PAD_CLONE_VARS(proto_perl, param) \
513 PL_comppad = av_dup(proto_perl->Icomppad, param); \
514 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
516 padnamelist_dup(proto_perl->Icomppad_name, param); \
517 PL_comppad_name_fill = proto_perl->Icomppad_name_fill; \
518 PL_comppad_name_floor = proto_perl->Icomppad_name_floor; \
519 PL_min_intro_pending = proto_perl->Imin_intro_pending; \
520 PL_max_intro_pending = proto_perl->Imax_intro_pending; \
521 PL_padix = proto_perl->Ipadix; \
522 PL_padix_floor = proto_perl->Ipadix_floor; \
523 PL_pad_reset_pending = proto_perl->Ipad_reset_pending; \
524 PL_cop_seqmax = proto_perl->Icop_seqmax;
527 =for apidoc Am|PADOFFSET|pad_add_name_pvs|"name"|U32 flags|HV *typestash|HV *ourstash
529 Exactly like L</pad_add_name_pvn>, but takes a literal string
530 instead of a string/length pair.
535 #define pad_add_name_pvs(name,flags,typestash,ourstash) \
536 Perl_pad_add_name_pvn(aTHX_ STR_WITH_LEN(name), flags, typestash, ourstash)
539 =for apidoc Am|PADOFFSET|pad_findmy_pvs|"name"|U32 flags
541 Exactly like L</pad_findmy_pvn>, but takes a literal string
542 instead of a string/length pair.
547 #define pad_findmy_pvs(name,flags) \
548 Perl_pad_findmy_pvn(aTHX_ STR_WITH_LEN(name), flags)
550 struct suspended_compcv
553 STRLEN padix, constpadix;
554 STRLEN comppad_name_fill;
555 STRLEN min_intro_pending, max_intro_pending;
556 bool cv_has_eval, pad_reset_pending;
559 #define resume_compcv_final(buffer) Perl_resume_compcv(aTHX_ buffer, false)
560 #define resume_compcv_and_save(buffer) Perl_resume_compcv(aTHX_ buffer, true)
563 * ex: set ts=8 sts=4 sw=4 et: