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 index 0 is a padnamelist * */
30 PAD * pad_1; /* this slice of PAD * array always alloced */
31 PAD * pad_2; /* maybe unalloced */
32 } * xpadlarr_dbg; /* for use with a C debugger only */
34 U32 xpadl_id; /* Semi-unique ID, shared between clones */
35 U32 xpadl_outid; /* ID of outer pad */
39 SSize_t xpadnl_fill; /* max index in use */
40 PADNAME ** xpadnl_alloc; /* pointer to beginning of array */
41 SSize_t xpadnl_max; /* max index for which array has space */
42 PADOFFSET xpadnl_max_named; /* highest index with len > 0 */
46 /* PERL_PADNAME_MINIMAL uses less memory, but on some platforms
47 PERL_PADNAME_ALIGNED may be faster, so platform-specific hints can
48 define one or the other. */
49 #if defined(PERL_PADNAME_MINIMAL) && defined (PERL_PADNAME_ALIGNED)
50 # error PERL_PADNAME_MINIMAL and PERL_PADNAME_ALIGNED are exclusive
53 #if !defined(PERL_PADNAME_MINIMAL) && !defined(PERL_PADNAME_ALIGNED)
54 # define PERL_PADNAME_MINIMAL
57 #define _PADNAME_BASE \
59 HV * xpadn_ourstash; \
61 HV * xpadn_typestash; \
75 struct padname_with_str {
76 #ifdef PERL_PADNAME_MINIMAL
79 struct padname xpadn_padname;
86 #define PADNAME_FROM_PV(s) \
87 ((PADNAME *)((s) - STRUCT_OFFSET(struct padname_with_str, xpadn_str)))
90 /* a value that PL_cop_seqmax is guaranteed never to be,
91 * flagging that a lexical is being introduced, or has not yet left scope
93 #define PERL_PADSEQ_INTRO U32_MAX
94 #define COP_SEQMAX_INC \
96 (void)(PL_cop_seqmax == PERL_PADSEQ_INTRO && PL_cop_seqmax++))
99 /* B.xs needs these for the benefit of B::Deparse */
100 /* Low range end is exclusive (valid from the cop seq after this one) */
101 /* High range end is inclusive (valid up to this cop seq) */
103 #define COP_SEQ_RANGE_LOW(pn) (pn)->xpadn_low
104 #define COP_SEQ_RANGE_HIGH(pn) (pn)->xpadn_high
105 #define PARENT_PAD_INDEX(pn) (pn)->xpadn_low
106 #define PARENT_FAKELEX_FLAGS(pn) (pn)->xpadn_high
108 /* Flags set in the SvIVX field of FAKE namesvs */
110 #define PAD_FAKELEX_ANON 1 /* the lex is declared in an ANON, or ... */
111 #define PAD_FAKELEX_MULTI 2 /* the lex can be instantiated multiple times */
113 /* flags for the pad_new() function */
115 #define padnew_CLONE 1 /* this pad is for a cloned CV */
116 #define padnew_SAVE 2 /* save old globals */
117 #define padnew_SAVESUB 4 /* also save extra stuff for start of sub */
119 /* values for the pad_tidy() function */
122 padtidy_SUB, /* tidy up a pad for a sub, */
123 padtidy_SUBCLONE, /* a cloned sub, */
124 padtidy_FORMAT /* or a format */
127 /* flags for pad_add_name_pvn. */
129 #define padadd_OUR 0x01 /* our declaration. */
130 #define padadd_STATE 0x02 /* state declaration. */
131 #define padadd_NO_DUP_CHECK 0x04 /* skip warning on dups. */
132 #define padadd_STALEOK 0x08 /* allow stale lexical in active
133 * sub, but only one level up */
135 /* ASSERT_CURPAD_LEGAL and ASSERT_CURPAD_ACTIVE respectively determine
136 * whether PL_comppad and PL_curpad are consistent and whether they have
139 # define pad_peg(label)
142 # define ASSERT_CURPAD_LEGAL(label) \
144 if (PL_comppad ? (AvARRAY(PL_comppad) != PL_curpad) : (PL_curpad != 0)) \
145 Perl_croak(aTHX_ "panic: illegal pad in %s: 0x%" UVxf "[0x%" UVxf "]",\
146 label, PTR2UV(PL_comppad), PTR2UV(PL_curpad));
149 # define ASSERT_CURPAD_ACTIVE(label) \
151 if (!PL_comppad || (AvARRAY(PL_comppad) != PL_curpad)) \
152 Perl_croak(aTHX_ "panic: invalid pad in %s: 0x%" UVxf "[0x%" UVxf "]",\
153 label, PTR2UV(PL_comppad), PTR2UV(PL_curpad));
155 # define ASSERT_CURPAD_LEGAL(label)
156 # define ASSERT_CURPAD_ACTIVE(label)
161 /* Note: the following three macros are actually defined in scope.h, but
162 * they are documented here for completeness, since they directly or
163 * indirectly affect pads.
165 =for apidoc m|void|SAVEPADSV |PADOFFSET po
166 Save a pad slot (used to restore after an iteration)
170 XXX DAPM it would make more sense to make the arg a PADOFFSET
172 =for apidoc m|void|SAVECLEARSV |SV **svp
173 Clear the pointed to pad value on scope exit. (i.e. the runtime action of
176 =for apidoc m|void|SAVECOMPPAD
177 save C<PL_comppad> and C<PL_curpad>
180 =for apidoc Amx|PAD **|PadlistARRAY|PADLIST * padlist
181 The C array of a padlist, containing the pads. Only subscript it with
182 numbers >= 1, as the 0th entry is not guaranteed to remain usable.
184 =for apidoc Amx|SSize_t|PadlistMAX|PADLIST * padlist
185 The index of the last allocated space in the padlist. Note that the last
186 pad may be in an earlier slot. Any entries following it will be C<NULL> in
189 =for apidoc Amx|PADNAMELIST *|PadlistNAMES|PADLIST * padlist
190 The names associated with pad entries.
192 =for apidoc Amx|PADNAME **|PadlistNAMESARRAY|PADLIST * padlist
193 The C array of pad names.
195 =for apidoc Amx|SSize_t|PadlistNAMESMAX|PADLIST * padlist
196 The index of the last pad name.
198 =for apidoc Amx|U32|PadlistREFCNT|PADLIST * padlist
199 The reference count of the padlist. Currently this is always 1.
201 =for apidoc Amx|PADNAME **|PadnamelistARRAY|PADNAMELIST * pnl
202 The C array of pad names.
204 =for apidoc Amx|SSize_t|PadnamelistMAX|PADNAMELIST * pnl
205 The index of the last pad name.
207 =for apidoc Amx|SSize_t|PadnamelistREFCNT|PADNAMELIST * pnl
208 The reference count of the pad name list.
210 =for apidoc Amx|void|PadnamelistREFCNT_dec|PADNAMELIST * pnl
211 Lowers the reference count of the pad name list.
213 =for apidoc Amx|SV **|PadARRAY|PAD * pad
214 The C array of pad entries.
216 =for apidoc Amx|SSize_t|PadMAX|PAD * pad
217 The index of the last pad entry.
219 =for apidoc Amx|char *|PadnamePV|PADNAME * pn
220 The name stored in the pad name struct. This returns C<NULL> for a target
223 =for apidoc Amx|STRLEN|PadnameLEN|PADNAME * pn
224 The length of the name.
226 =for apidoc Amx|bool|PadnameUTF8|PADNAME * pn
227 Whether PadnamePV is in UTF-8. Currently, this is always true.
229 =for apidoc Amx|SV *|PadnameSV|PADNAME * pn
230 Returns the pad name as a mortal SV.
232 =for apidoc m|bool|PadnameIsOUR|PADNAME * pn
233 Whether this is an "our" variable.
235 =for apidoc m|HV *|PadnameOURSTASH|PADNAME * pn
236 The stash in which this "our" variable was declared.
238 =for apidoc m|bool|PadnameOUTER|PADNAME * pn
239 Whether this entry belongs to an outer pad. Entries for which this is true
240 are often referred to as 'fake'.
242 =for apidoc m|bool|PadnameIsSTATE|PADNAME * pn
243 Whether this is a "state" variable.
245 =for apidoc m|HV *|PadnameTYPE|PADNAME * pn
246 The stash associated with a typed lexical. This returns the C<%Foo::> hash
249 =for apidoc Amx|SSize_t|PadnameREFCNT|PADNAME * pn
250 The reference count of the pad name.
252 =for apidoc Amx|PADNAME *|PadnameREFCNT_inc|PADNAME * pn
253 Increases the reference count of the pad name. Returns the pad name itself.
255 =for apidoc Amx|void|PadnameREFCNT_dec|PADNAME * pn
256 Lowers the reference count of the pad name.
259 =for apidoc m|SV *|PAD_SETSV |PADOFFSET po|SV* sv
260 Set the slot at offset C<po> in the current pad to C<sv>
262 =for apidoc m|SV *|PAD_SV |PADOFFSET po
263 Get the value at offset C<po> in the current pad
265 =for apidoc m|SV *|PAD_SVl |PADOFFSET po
266 Lightweight and lvalue version of C<PAD_SV>.
267 Get or set the value at offset C<po> in the current pad.
268 Unlike C<PAD_SV>, does not print diagnostics with -DX.
269 For internal use only.
271 =for apidoc m|SV *|PAD_BASE_SV |PADLIST padlist|PADOFFSET po
272 Get the value from slot C<po> in the base (DEPTH=1) pad of a padlist
274 =for apidoc m|void|PAD_SET_CUR |PADLIST padlist|I32 n
275 Set the current pad to be pad C<n> in the padlist, saving
276 the previous current pad. NB currently this macro expands to a string too
277 long for some compilers, so it's best to replace it with
280 PAD_SET_CUR_NOSAVE(padlist,n);
283 =for apidoc m|void|PAD_SET_CUR_NOSAVE |PADLIST padlist|I32 n
284 like PAD_SET_CUR, but without the save
286 =for apidoc m|void|PAD_SAVE_SETNULLPAD
287 Save the current pad then set it to null.
289 =for apidoc m|void|PAD_SAVE_LOCAL|PAD *opad|PAD *npad
290 Save the current pad to the local variable C<opad>, then make the
291 current pad equal to C<npad>
293 =for apidoc m|void|PAD_RESTORE_LOCAL|PAD *opad
294 Restore the old pad saved into the local variable C<opad> by C<PAD_SAVE_LOCAL()>
299 #define PadlistARRAY(pl) (pl)->xpadl_arr.xpadlarr_alloc
300 #define PadlistMAX(pl) (pl)->xpadl_max
301 #define PadlistNAMES(pl) *((PADNAMELIST **)PadlistARRAY(pl))
302 #define PadlistNAMESARRAY(pl) PadnamelistARRAY(PadlistNAMES(pl))
303 #define PadlistNAMESMAX(pl) PadnamelistMAX(PadlistNAMES(pl))
304 #define PadlistREFCNT(pl) 1 /* reserved for future use */
306 #define PadnamelistARRAY(pnl) (pnl)->xpadnl_alloc
307 #define PadnamelistMAX(pnl) (pnl)->xpadnl_fill
308 #define PadnamelistMAXNAMED(pnl) (pnl)->xpadnl_max_named
309 #define PadnamelistREFCNT(pnl) (pnl)->xpadnl_refcnt
310 #define PadnamelistREFCNT_dec(pnl) Perl_padnamelist_free(aTHX_ pnl)
312 #define PadARRAY(pad) AvARRAY(pad)
313 #define PadMAX(pad) AvFILLp(pad)
315 #define PadnamePV(pn) (pn)->xpadn_pv
316 #define PadnameLEN(pn) (pn)->xpadn_len
317 #define PadnameUTF8(pn) 1
318 #define PadnameSV(pn) \
319 newSVpvn_flags(PadnamePV(pn), PadnameLEN(pn), SVs_TEMP|SVf_UTF8)
320 #define PadnameFLAGS(pn) (pn)->xpadn_flags
321 #define PadnameIsOUR(pn) cBOOL((pn)->xpadn_ourstash)
322 #define PadnameOURSTASH(pn) (pn)->xpadn_ourstash
323 #define PadnameTYPE(pn) (pn)->xpadn_type_u.xpadn_typestash
324 #define PadnameHasTYPE(pn) cBOOL(PadnameTYPE(pn))
325 #define PadnamePROTOCV(pn) (pn)->xpadn_type_u.xpadn_protocv
326 #define PadnameREFCNT(pn) (pn)->xpadn_refcnt
327 #define PadnameREFCNT_inc(pn) Perl_padname_refcnt_inc(pn)
328 #define PadnameREFCNT_dec(pn) Perl_padname_free(aTHX_ pn)
329 #define PadnameOURSTASH_set(pn,s) (PadnameOURSTASH(pn) = (s))
330 #define PadnameTYPE_set(pn,s) (PadnameTYPE(pn) = (s))
331 #define PadnameOUTER(pn) (PadnameFLAGS(pn) & PADNAMEf_OUTER)
332 #define PadnameIsSTATE(pn) (PadnameFLAGS(pn) & PADNAMEf_STATE)
333 #define PadnameLVALUE(pn) (PadnameFLAGS(pn) & PADNAMEf_LVALUE)
335 #define PadnameLVALUE_on(pn) (PadnameFLAGS(pn) |= PADNAMEf_LVALUE)
336 #define PadnameIsSTATE_on(pn) (PadnameFLAGS(pn) |= PADNAMEf_STATE)
338 #define PADNAMEf_OUTER 0x01 /* outer lexical var */
339 #define PADNAMEf_STATE 0x02 /* state var */
340 #define PADNAMEf_LVALUE 0x04 /* used as lvalue */
341 #define PADNAMEf_TYPED 0x08 /* for B; unused by core */
342 #define PADNAMEf_OUR 0x10 /* for B; unused by core */
344 /* backward compatibility */
346 # define SvPAD_STATE PadnameIsSTATE
347 # define SvPAD_TYPED PadnameHasTYPE
348 # define SvPAD_OUR(pn) cBOOL(PadnameOURSTASH(pn))
349 # define SvPAD_STATE_on PadnameIsSTATE_on
350 # define SvPAD_TYPED_on(pn) (PadnameFLAGS(pn) |= PADNAMEf_TYPED)
351 # define SvPAD_OUR_on(pn) (PadnameFLAGS(pn) |= PADNAMEf_OUR)
352 # define SvOURSTASH PadnameOURSTASH
353 # define SvOURSTASH_set PadnameOURSTASH_set
354 # define SVpad_STATE PADNAMEf_STATE
355 # define SVpad_TYPED PADNAMEf_TYPED
356 # define SVpad_OUR PADNAMEf_OUR
357 # define PADNAMEt_OUTER PADNAMEf_OUTER
358 # define PADNAMEt_STATE PADNAMEf_STATE
359 # define PADNAMEt_LVALUE PADNAMEf_LVALUE
360 # define PADNAMEt_TYPED PADNAMEf_TYPED
361 # define PADNAMEt_OUR PADNAMEf_OUR
365 # define PAD_SV(po) pad_sv(po)
366 # define PAD_SETSV(po,sv) pad_setsv(po,sv)
368 # define PAD_SV(po) (PL_curpad[po])
369 # define PAD_SETSV(po,sv) PL_curpad[po] = (sv)
372 #define PAD_SVl(po) (PL_curpad[po])
374 #define PAD_BASE_SV(padlist, po) \
375 (PadlistARRAY(padlist)[1]) \
376 ? AvARRAY(MUTABLE_AV((PadlistARRAY(padlist)[1])))[po] \
380 #define PAD_SET_CUR_NOSAVE(padlist,nth) \
381 PL_comppad = (PAD*) (PadlistARRAY(padlist)[nth]); \
382 PL_curpad = AvARRAY(PL_comppad); \
383 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
384 "Pad 0x%" UVxf "[0x%" UVxf "] set_cur depth=%d\n", \
385 PTR2UV(PL_comppad), PTR2UV(PL_curpad), (int)(nth)));
388 #define PAD_SET_CUR(padlist,nth) \
390 PAD_SET_CUR_NOSAVE(padlist,nth);
393 #define PAD_SAVE_SETNULLPAD() SAVECOMPPAD(); \
394 PL_comppad = NULL; PL_curpad = NULL; \
395 DEBUG_Xv(PerlIO_printf(Perl_debug_log, "Pad set_null\n"));
397 #define PAD_SAVE_LOCAL(opad,npad) \
399 PL_comppad = (npad); \
400 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
401 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
402 "Pad 0x%" UVxf "[0x%" UVxf "] save_local\n", \
403 PTR2UV(PL_comppad), PTR2UV(PL_curpad)));
405 #define PAD_RESTORE_LOCAL(opad) \
406 assert(!opad || !SvIS_FREED(opad)); \
408 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
409 DEBUG_Xv(PerlIO_printf(Perl_debug_log, \
410 "Pad 0x%" UVxf "[0x%" UVxf "] restore_local\n", \
411 PTR2UV(PL_comppad), PTR2UV(PL_curpad)));
415 =for apidoc m|void|CX_CURPAD_SAVE|struct context
416 Save the current pad in the given context block structure.
418 =for apidoc m|SV *|CX_CURPAD_SV|struct context|PADOFFSET po
419 Access the SV at offset C<po> in the saved current pad in the given
420 context block structure (can be used as an lvalue).
425 #define CX_CURPAD_SAVE(block) (block).oldcomppad = PL_comppad
426 #define CX_CURPAD_SV(block,po) (AvARRAY(MUTABLE_AV(((block).oldcomppad)))[po])
430 =for apidoc m|U32|PAD_COMPNAME_FLAGS|PADOFFSET po
431 Return the flags for the current compiling pad name
432 at offset C<po>. Assumes a valid slot entry.
434 =for apidoc m|char *|PAD_COMPNAME_PV|PADOFFSET po
435 Return the name of the current compiling pad name
436 at offset C<po>. Assumes a valid slot entry.
438 =for apidoc m|HV *|PAD_COMPNAME_TYPE|PADOFFSET po
439 Return the type (stash) of the current compiling pad name at offset
440 C<po>. Must be a valid name. Returns null if not typed.
442 =for apidoc m|HV *|PAD_COMPNAME_OURSTASH|PADOFFSET po
443 Return the stash associated with an C<our> variable.
444 Assumes the slot entry is a valid C<our> lexical.
446 =for apidoc m|STRLEN|PAD_COMPNAME_GEN|PADOFFSET po
447 The generation number of the name at offset C<po> in the current
448 compiling pad (lvalue).
450 =for apidoc m|STRLEN|PAD_COMPNAME_GEN_set|PADOFFSET po|int gen
451 Sets the generation number of the name at offset C<po> in the current
452 ling pad (lvalue) to C<gen>.
457 #define PAD_COMPNAME(po) PAD_COMPNAME_SV(po)
458 #define PAD_COMPNAME_SV(po) (PadnamelistARRAY(PL_comppad_name)[(po)])
459 #define PAD_COMPNAME_FLAGS(po) PadnameFLAGS(PAD_COMPNAME(po))
460 #define PAD_COMPNAME_FLAGS_isOUR(po) PadnameIsOUR(PAD_COMPNAME_SV(po))
461 #define PAD_COMPNAME_PV(po) PadnamePV(PAD_COMPNAME(po))
463 #define PAD_COMPNAME_TYPE(po) PadnameTYPE(PAD_COMPNAME(po))
465 #define PAD_COMPNAME_OURSTASH(po) (PadnameOURSTASH(PAD_COMPNAME_SV(po)))
467 #define PAD_COMPNAME_GEN(po) \
468 ((STRLEN)PadnamelistARRAY(PL_comppad_name)[po]->xpadn_gen)
470 #define PAD_COMPNAME_GEN_set(po, gen) \
471 (PadnamelistARRAY(PL_comppad_name)[po]->xpadn_gen = (gen))
475 =for apidoc m|void|PAD_CLONE_VARS|PerlInterpreter *proto_perl|CLONE_PARAMS* param
476 Clone the state variables associated with running and compiling pads.
481 /* NB - we set PL_comppad to null unless it points at a value that
482 * has already been dup'ed, ie it points to part of an active padlist.
483 * Otherwise PL_comppad ends up being a leaked scalar in code like
485 * threads->create(sub { threads->create(sub {...} ) } );
486 * where the second thread dups the outer sub's comppad but not the
487 * sub's CV or padlist. */
489 #define PAD_CLONE_VARS(proto_perl, param) \
490 PL_comppad = av_dup(proto_perl->Icomppad, param); \
491 PL_curpad = PL_comppad ? AvARRAY(PL_comppad) : NULL; \
493 padnamelist_dup(proto_perl->Icomppad_name, param); \
494 PL_comppad_name_fill = proto_perl->Icomppad_name_fill; \
495 PL_comppad_name_floor = proto_perl->Icomppad_name_floor; \
496 PL_min_intro_pending = proto_perl->Imin_intro_pending; \
497 PL_max_intro_pending = proto_perl->Imax_intro_pending; \
498 PL_padix = proto_perl->Ipadix; \
499 PL_padix_floor = proto_perl->Ipadix_floor; \
500 PL_pad_reset_pending = proto_perl->Ipad_reset_pending; \
501 PL_cop_seqmax = proto_perl->Icop_seqmax;
504 =for apidoc Am|PADOFFSET|pad_add_name_pvs|"name"|U32 flags|HV *typestash|HV *ourstash
506 Exactly like L</pad_add_name_pvn>, but takes a literal string
507 instead of a string/length pair.
512 #define pad_add_name_pvs(name,flags,typestash,ourstash) \
513 Perl_pad_add_name_pvn(aTHX_ STR_WITH_LEN(name), flags, typestash, ourstash)
516 =for apidoc Am|PADOFFSET|pad_findmy_pvs|"name"|U32 flags
518 Exactly like L</pad_findmy_pvn>, but takes a literal string
519 instead of a string/length pair.
524 #define pad_findmy_pvs(name,flags) \
525 Perl_pad_findmy_pvn(aTHX_ STR_WITH_LEN(name), flags)
528 * ex: set ts=8 sts=4 sw=4 et: