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add CXp_FOR_PAD, CXp_FOR_GV flags
[perl5.git] / cop.h
1 /*    cop.h
2  *
3  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4  *    2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 by Larry Wall and others
5  *
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.
8  *
9  * Control ops (cops) are one of the two ops OP_NEXTSTATE and OP_DBSTATE,
10  * that (loosely speaking) are statement separators.
11  * They hold information important for lexical state and error reporting.
12  * At run time, PL_curcop is set to point to the most recently executed cop,
13  * and thus can be used to determine our current state.
14  */
15
16 /* A jmpenv packages the state required to perform a proper non-local jump.
17  * Note that there is a PL_start_env initialized when perl starts, and
18  * PL_top_env points to this initially, so PL_top_env should always be
19  * non-null.
20  *
21  * Existence of a non-null PL_top_env->je_prev implies it is valid to call
22  * longjmp() at that runlevel (we make sure PL_start_env.je_prev is always
23  * null to ensure this).
24  *
25  * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
26  * establish a local jmpenv to handle exception traps.  Care must be taken
27  * to restore the previous value of je_mustcatch before exiting the
28  * stack frame iff JMPENV_PUSH was not called in that stack frame.
29  * GSAR 97-03-27
30  */
31
32 struct jmpenv {
33     struct jmpenv *     je_prev;
34     Sigjmp_buf          je_buf;         /* uninit if je_prev is NULL */
35     int                 je_ret;         /* last exception thrown */
36     bool                je_mustcatch;   /* need to call longjmp()? */
37     U16                 je_old_delaymagic; /* saved PL_delaymagic */
38 };
39
40 typedef struct jmpenv JMPENV;
41
42 /*
43  * How to build the first jmpenv.
44  *
45  * top_env needs to be non-zero. It points to an area
46  * in which longjmp() stuff is stored, as C callstack
47  * info there at least is thread specific this has to
48  * be per-thread. Otherwise a 'die' in a thread gives
49  * that thread the C stack of last thread to do an eval {}!
50  */
51
52 #define JMPENV_BOOTSTRAP \
53     STMT_START {                                \
54         PERL_POISON_EXPR(PoisonNew(&PL_start_env, 1, JMPENV));\
55         PL_top_env = &PL_start_env;             \
56         PL_start_env.je_prev = NULL;            \
57         PL_start_env.je_ret = -1;               \
58         PL_start_env.je_mustcatch = TRUE;       \
59         PL_start_env.je_old_delaymagic = 0;     \
60     } STMT_END
61
62 /*
63  *   PERL_FLEXIBLE_EXCEPTIONS
64  * 
65  * All the flexible exceptions code has been removed.
66  * See the following threads for details:
67  *
68  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2004-07/msg00378.html
69  * 
70  * Joshua's original patches (which weren't applied) and discussion:
71  * 
72  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01396.html
73  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01489.html
74  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01491.html
75  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01608.html
76  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02144.html
77  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02998.html
78  * 
79  * Chip's reworked patch and discussion:
80  * 
81  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-03/msg00520.html
82  * 
83  * The flaw in these patches (which went unnoticed at the time) was
84  * that they moved some code that could potentially die() out of the
85  * region protected by the setjmp()s.  This caused exceptions within
86  * END blocks and such to not be handled by the correct setjmp().
87  * 
88  * The original patches that introduces flexible exceptions were:
89  *
90  * http://perl5.git.perl.org/perl.git/commit/312caa8e97f1c7ee342a9895c2f0e749625b4929
91  * http://perl5.git.perl.org/perl.git/commit/14dd3ad8c9bf82cf09798a22cc89a9862dfd6d1a                                        
92  *  
93  */
94
95 #define dJMPENV         JMPENV cur_env
96
97 #define JMPENV_PUSH(v) \
98     STMT_START {                                                        \
99         DEBUG_l({                                                       \
100             int i = 0; JMPENV *p = PL_top_env;                          \
101             while (p) { i++; p = p->je_prev; }                          \
102             Perl_deb(aTHX_ "JUMPENV_PUSH level=%d at %s:%d\n",          \
103                          i,  __FILE__, __LINE__);})                     \
104         cur_env.je_prev = PL_top_env;                                   \
105         cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK);              \
106         PL_top_env = &cur_env;                                          \
107         cur_env.je_mustcatch = FALSE;                                   \
108         cur_env.je_old_delaymagic = PL_delaymagic;                      \
109         (v) = cur_env.je_ret;                                           \
110     } STMT_END
111
112 #define JMPENV_POP \
113     STMT_START {                                                        \
114         DEBUG_l({                                                       \
115             int i = -1; JMPENV *p = PL_top_env;                         \
116             while (p) { i++; p = p->je_prev; }                          \
117             Perl_deb(aTHX_ "JUMPENV_POP level=%d at %s:%d\n",           \
118                          i, __FILE__, __LINE__);})                      \
119         assert(PL_top_env == &cur_env);                                 \
120         PL_delaymagic = cur_env.je_old_delaymagic;                      \
121         PL_top_env = cur_env.je_prev;                                   \
122     } STMT_END
123
124 #define JMPENV_JUMP(v) \
125     STMT_START {                                                \
126         DEBUG_l({                                               \
127             int i = -1; JMPENV *p = PL_top_env;                 \
128             while (p) { i++; p = p->je_prev; }                  \
129             Perl_deb(aTHX_ "JUMPENV_JUMP(%d) level=%d at %s:%d\n", \
130                          (int)v, i, __FILE__, __LINE__);})      \
131         if (PL_top_env->je_prev)                                \
132             PerlProc_longjmp(PL_top_env->je_buf, (v));          \
133         if ((v) == 2)                                           \
134             PerlProc_exit(STATUS_EXIT);                         \
135         PerlIO_printf(PerlIO_stderr(), "panic: top_env, v=%d\n", (int)v); \
136         PerlProc_exit(1);                                       \
137     } STMT_END
138
139 #define CATCH_GET               (PL_top_env->je_mustcatch)
140 #define CATCH_SET(v) \
141     STMT_START {                                                        \
142         DEBUG_l(                                                        \
143             Perl_deb(aTHX_                                              \
144                 "JUMPLEVEL set catch %d => %d (for %p) at %s:%d\n",     \
145                  PL_top_env->je_mustcatch, v, (void*)PL_top_env,        \
146                  __FILE__, __LINE__);)                                  \
147         PL_top_env->je_mustcatch = (v);                                 \
148     } STMT_END
149
150 /*
151 =head1 COP Hint Hashes
152 */
153
154 typedef struct refcounted_he COPHH;
155
156 #define COPHH_KEY_UTF8 REFCOUNTED_HE_KEY_UTF8
157
158 /*
159 =for apidoc Amx|SV *|cophh_fetch_pvn|const COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
160
161 Look up the entry in the cop hints hash C<cophh> with the key specified by
162 C<keypv> and C<keylen>.  If C<flags> has the C<COPHH_KEY_UTF8> bit set,
163 the key octets are interpreted as UTF-8, otherwise they are interpreted
164 as Latin-1.  C<hash> is a precomputed hash of the key string, or zero if
165 it has not been precomputed.  Returns a mortal scalar copy of the value
166 associated with the key, or C<&PL_sv_placeholder> if there is no value
167 associated with the key.
168
169 =cut
170 */
171
172 #define cophh_fetch_pvn(cophh, keypv, keylen, hash, flags) \
173     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, keypv, keylen, hash, flags)
174
175 /*
176 =for apidoc Amx|SV *|cophh_fetch_pvs|const COPHH *cophh|const char *key|U32 flags
177
178 Like L</cophh_fetch_pvn>, but takes a literal string instead of a
179 string/length pair, and no precomputed hash.
180
181 =cut
182 */
183
184 #define cophh_fetch_pvs(cophh, key, flags) \
185     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, flags)
186
187 /*
188 =for apidoc Amx|SV *|cophh_fetch_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
189
190 Like L</cophh_fetch_pvn>, but takes a nul-terminated string instead of
191 a string/length pair.
192
193 =cut
194 */
195
196 #define cophh_fetch_pv(cophh, key, hash, flags) \
197     Perl_refcounted_he_fetch_pv(aTHX_ cophh, key, hash, flags)
198
199 /*
200 =for apidoc Amx|SV *|cophh_fetch_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
201
202 Like L</cophh_fetch_pvn>, but takes a Perl scalar instead of a
203 string/length pair.
204
205 =cut
206 */
207
208 #define cophh_fetch_sv(cophh, key, hash, flags) \
209     Perl_refcounted_he_fetch_sv(aTHX_ cophh, key, hash, flags)
210
211 /*
212 =for apidoc Amx|HV *|cophh_2hv|const COPHH *cophh|U32 flags
213
214 Generates and returns a standard Perl hash representing the full set of
215 key/value pairs in the cop hints hash C<cophh>.  C<flags> is currently
216 unused and must be zero.
217
218 =cut
219 */
220
221 #define cophh_2hv(cophh, flags) \
222     Perl_refcounted_he_chain_2hv(aTHX_ cophh, flags)
223
224 /*
225 =for apidoc Amx|COPHH *|cophh_copy|COPHH *cophh
226
227 Make and return a complete copy of the cop hints hash C<cophh>.
228
229 =cut
230 */
231
232 #define cophh_copy(cophh) Perl_refcounted_he_inc(aTHX_ cophh)
233
234 /*
235 =for apidoc Amx|void|cophh_free|COPHH *cophh
236
237 Discard the cop hints hash C<cophh>, freeing all resources associated
238 with it.
239
240 =cut
241 */
242
243 #define cophh_free(cophh) Perl_refcounted_he_free(aTHX_ cophh)
244
245 /*
246 =for apidoc Amx|COPHH *|cophh_new_empty
247
248 Generate and return a fresh cop hints hash containing no entries.
249
250 =cut
251 */
252
253 #define cophh_new_empty() ((COPHH *)NULL)
254
255 /*
256 =for apidoc Amx|COPHH *|cophh_store_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|SV *value|U32 flags
257
258 Stores a value, associated with a key, in the cop hints hash C<cophh>,
259 and returns the modified hash.  The returned hash pointer is in general
260 not the same as the hash pointer that was passed in.  The input hash is
261 consumed by the function, and the pointer to it must not be subsequently
262 used.  Use L</cophh_copy> if you need both hashes.
263
264 The key is specified by C<keypv> and C<keylen>.  If C<flags> has the
265 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
266 otherwise they are interpreted as Latin-1.  C<hash> is a precomputed
267 hash of the key string, or zero if it has not been precomputed.
268
269 C<value> is the scalar value to store for this key.  C<value> is copied
270 by this function, which thus does not take ownership of any reference
271 to it, and later changes to the scalar will not be reflected in the
272 value visible in the cop hints hash.  Complex types of scalar will not
273 be stored with referential integrity, but will be coerced to strings.
274
275 =cut
276 */
277
278 #define cophh_store_pvn(cophh, keypv, keylen, hash, value, flags) \
279     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, value, flags)
280
281 /*
282 =for apidoc Amx|COPHH *|cophh_store_pvs|const COPHH *cophh|const char *key|SV *value|U32 flags
283
284 Like L</cophh_store_pvn>, but takes a literal string instead of a
285 string/length pair, and no precomputed hash.
286
287 =cut
288 */
289
290 #define cophh_store_pvs(cophh, key, value, flags) \
291     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, value, flags)
292
293 /*
294 =for apidoc Amx|COPHH *|cophh_store_pv|const COPHH *cophh|const char *key|U32 hash|SV *value|U32 flags
295
296 Like L</cophh_store_pvn>, but takes a nul-terminated string instead of
297 a string/length pair.
298
299 =cut
300 */
301
302 #define cophh_store_pv(cophh, key, hash, value, flags) \
303     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, value, flags)
304
305 /*
306 =for apidoc Amx|COPHH *|cophh_store_sv|const COPHH *cophh|SV *key|U32 hash|SV *value|U32 flags
307
308 Like L</cophh_store_pvn>, but takes a Perl scalar instead of a
309 string/length pair.
310
311 =cut
312 */
313
314 #define cophh_store_sv(cophh, key, hash, value, flags) \
315     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, value, flags)
316
317 /*
318 =for apidoc Amx|COPHH *|cophh_delete_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
319
320 Delete a key and its associated value from the cop hints hash C<cophh>,
321 and returns the modified hash.  The returned hash pointer is in general
322 not the same as the hash pointer that was passed in.  The input hash is
323 consumed by the function, and the pointer to it must not be subsequently
324 used.  Use L</cophh_copy> if you need both hashes.
325
326 The key is specified by C<keypv> and C<keylen>.  If C<flags> has the
327 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
328 otherwise they are interpreted as Latin-1.  C<hash> is a precomputed
329 hash of the key string, or zero if it has not been precomputed.
330
331 =cut
332 */
333
334 #define cophh_delete_pvn(cophh, keypv, keylen, hash, flags) \
335     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, \
336         (SV *)NULL, flags)
337
338 /*
339 =for apidoc Amx|COPHH *|cophh_delete_pvs|const COPHH *cophh|const char *key|U32 flags
340
341 Like L</cophh_delete_pvn>, but takes a literal string instead of a
342 string/length pair, and no precomputed hash.
343
344 =cut
345 */
346
347 #define cophh_delete_pvs(cophh, key, flags) \
348     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, \
349         (SV *)NULL, flags)
350
351 /*
352 =for apidoc Amx|COPHH *|cophh_delete_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
353
354 Like L</cophh_delete_pvn>, but takes a nul-terminated string instead of
355 a string/length pair.
356
357 =cut
358 */
359
360 #define cophh_delete_pv(cophh, key, hash, flags) \
361     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
362
363 /*
364 =for apidoc Amx|COPHH *|cophh_delete_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
365
366 Like L</cophh_delete_pvn>, but takes a Perl scalar instead of a
367 string/length pair.
368
369 =cut
370 */
371
372 #define cophh_delete_sv(cophh, key, hash, flags) \
373     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
374
375 #include "mydtrace.h"
376
377 struct cop {
378     BASEOP
379     /* On LP64 putting this here takes advantage of the fact that BASEOP isn't
380        an exact multiple of 8 bytes to save structure padding.  */
381     line_t      cop_line;       /* line # of this command */
382     /* label for this construct is now stored in cop_hints_hash */
383 #ifdef USE_ITHREADS
384     PADOFFSET   cop_stashoff;   /* offset into PL_stashpad, for the
385                                    package the line was compiled in */
386     char *      cop_file;       /* file name the following line # is from */
387 #else
388     HV *        cop_stash;      /* package line was compiled in */
389     GV *        cop_filegv;     /* file the following line # is from */
390 #endif
391     U32         cop_hints;      /* hints bits from pragmata */
392     U32         cop_seq;        /* parse sequence number */
393     /* Beware. mg.c and warnings.pl assume the type of this is STRLEN *:  */
394     STRLEN *    cop_warnings;   /* lexical warnings bitmask */
395     /* compile time state of %^H.  See the comment in op.c for how this is
396        used to recreate a hash to return from caller.  */
397     COPHH *     cop_hints_hash;
398 };
399
400 #ifdef USE_ITHREADS
401 #  define CopFILE(c)            ((c)->cop_file)
402 #  define CopFILEGV(c)          (CopFILE(c) \
403                                  ? gv_fetchfile(CopFILE(c)) : NULL)
404                                  
405 #  ifdef NETWARE
406 #    define CopFILE_set(c,pv)   ((c)->cop_file = savepv(pv))
407 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savepvn((pv),(l)))
408 #  else
409 #    define CopFILE_set(c,pv)   ((c)->cop_file = savesharedpv(pv))
410 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savesharedpvn((pv),(l)))
411 #  endif
412
413 #  define CopFILESV(c)          (CopFILE(c) \
414                                  ? GvSV(gv_fetchfile(CopFILE(c))) : NULL)
415 #  define CopFILEAV(c)          (CopFILE(c) \
416                                  ? GvAV(gv_fetchfile(CopFILE(c))) : NULL)
417 #  define CopFILEAVx(c)         (assert_(CopFILE(c)) \
418                                    GvAV(gv_fetchfile(CopFILE(c))))
419
420 #  define CopSTASH(c)           PL_stashpad[(c)->cop_stashoff]
421 #  define CopSTASH_set(c,hv)    ((c)->cop_stashoff = (hv)               \
422                                     ? alloccopstash(hv)                 \
423                                     : 0)
424 #  ifdef NETWARE
425 #    define CopFILE_free(c) SAVECOPFILE_FREE(c)
426 #  else
427 #    define CopFILE_free(c)     (PerlMemShared_free(CopFILE(c)),(CopFILE(c) = NULL))
428 #  endif
429 #else
430 #  define CopFILEGV(c)          ((c)->cop_filegv)
431 #  define CopFILEGV_set(c,gv)   ((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
432 #  define CopFILE_set(c,pv)     CopFILEGV_set((c), gv_fetchfile(pv))
433 #  define CopFILE_setn(c,pv,l)  CopFILEGV_set((c), gv_fetchfile_flags((pv),(l),0))
434 #  define CopFILESV(c)          (CopFILEGV(c) ? GvSV(CopFILEGV(c)) : NULL)
435 #  define CopFILEAV(c)          (CopFILEGV(c) ? GvAV(CopFILEGV(c)) : NULL)
436 #  ifdef DEBUGGING
437 #    define CopFILEAVx(c)       (assert(CopFILEGV(c)), GvAV(CopFILEGV(c)))
438 #  else
439 #    define CopFILEAVx(c)       (GvAV(CopFILEGV(c)))
440 # endif
441 #  define CopFILE(c)            (CopFILEGV(c) \
442                                     ? GvNAME(CopFILEGV(c))+2 : NULL)
443 #  define CopSTASH(c)           ((c)->cop_stash)
444 #  define CopSTASH_set(c,hv)    ((c)->cop_stash = (hv))
445 #  define CopFILE_free(c)       (SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = NULL))
446
447 #endif /* USE_ITHREADS */
448
449 #define CopSTASHPV(c)           (CopSTASH(c) ? HvNAME_get(CopSTASH(c)) : NULL)
450    /* cop_stash is not refcounted */
451 #define CopSTASHPV_set(c,pv)    CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
452 #define CopSTASH_eq(c,hv)       (CopSTASH(c) == (hv))
453
454 #define CopHINTHASH_get(c)      ((COPHH*)((c)->cop_hints_hash))
455 #define CopHINTHASH_set(c,h)    ((c)->cop_hints_hash = (h))
456
457 /*
458 =head1 COP Hint Reading
459 */
460
461 /*
462 =for apidoc Am|SV *|cop_hints_fetch_pvn|const COP *cop|const char *keypv|STRLEN keylen|U32 hash|U32 flags
463
464 Look up the hint entry in the cop C<cop> with the key specified by
465 C<keypv> and C<keylen>.  If C<flags> has the C<COPHH_KEY_UTF8> bit set,
466 the key octets are interpreted as UTF-8, otherwise they are interpreted
467 as Latin-1.  C<hash> is a precomputed hash of the key string, or zero if
468 it has not been precomputed.  Returns a mortal scalar copy of the value
469 associated with the key, or C<&PL_sv_placeholder> if there is no value
470 associated with the key.
471
472 =cut
473 */
474
475 #define cop_hints_fetch_pvn(cop, keypv, keylen, hash, flags) \
476     cophh_fetch_pvn(CopHINTHASH_get(cop), keypv, keylen, hash, flags)
477
478 /*
479 =for apidoc Am|SV *|cop_hints_fetch_pvs|const COP *cop|const char *key|U32 flags
480
481 Like L</cop_hints_fetch_pvn>, but takes a literal string instead of a
482 string/length pair, and no precomputed hash.
483
484 =cut
485 */
486
487 #define cop_hints_fetch_pvs(cop, key, flags) \
488     cophh_fetch_pvs(CopHINTHASH_get(cop), key, flags)
489
490 /*
491 =for apidoc Am|SV *|cop_hints_fetch_pv|const COP *cop|const char *key|U32 hash|U32 flags
492
493 Like L</cop_hints_fetch_pvn>, but takes a nul-terminated string instead
494 of a string/length pair.
495
496 =cut
497 */
498
499 #define cop_hints_fetch_pv(cop, key, hash, flags) \
500     cophh_fetch_pv(CopHINTHASH_get(cop), key, hash, flags)
501
502 /*
503 =for apidoc Am|SV *|cop_hints_fetch_sv|const COP *cop|SV *key|U32 hash|U32 flags
504
505 Like L</cop_hints_fetch_pvn>, but takes a Perl scalar instead of a
506 string/length pair.
507
508 =cut
509 */
510
511 #define cop_hints_fetch_sv(cop, key, hash, flags) \
512     cophh_fetch_sv(CopHINTHASH_get(cop), key, hash, flags)
513
514 /*
515 =for apidoc Am|HV *|cop_hints_2hv|const COP *cop|U32 flags
516
517 Generates and returns a standard Perl hash representing the full set of
518 hint entries in the cop C<cop>.  C<flags> is currently unused and must
519 be zero.
520
521 =cut
522 */
523
524 #define cop_hints_2hv(cop, flags) \
525     cophh_2hv(CopHINTHASH_get(cop), flags)
526
527 #define CopLABEL(c)  Perl_cop_fetch_label(aTHX_ (c), NULL, NULL)
528 #define CopLABEL_len(c,len)  Perl_cop_fetch_label(aTHX_ (c), len, NULL)
529 #define CopLABEL_len_flags(c,len,flags)  Perl_cop_fetch_label(aTHX_ (c), len, flags)
530 #define CopLABEL_alloc(pv)      ((pv)?savepv(pv):NULL)
531
532 #define CopSTASH_ne(c,hv)       (!CopSTASH_eq(c,hv))
533 #define CopLINE(c)              ((c)->cop_line)
534 #define CopLINE_inc(c)          (++CopLINE(c))
535 #define CopLINE_dec(c)          (--CopLINE(c))
536 #define CopLINE_set(c,l)        (CopLINE(c) = (l))
537
538 /* OutCopFILE() is CopFILE for output (caller, die, warn, etc.) */
539 #define OutCopFILE(c) CopFILE(c)
540
541 #define CopHINTS_get(c)         ((c)->cop_hints + 0)
542 #define CopHINTS_set(c, h)      STMT_START {                            \
543                                     (c)->cop_hints = (h);               \
544                                 } STMT_END
545
546 /*
547  * Here we have some enormously heavy (or at least ponderous) wizardry.
548  */
549
550 /* subroutine context */
551 struct block_sub {
552     OP *        retop;  /* op to execute on exit from sub */
553     I32         old_savestack_ix; /* saved PL_savestack_ix (also CXt_NULL) */
554     SSize_t     old_tmpsfloor; /* also used in CXt_NULL sort block */
555     /* Above here is the same for sub, format and eval.  */
556     PAD         *prevcomppad; /* the caller's PL_comppad */
557     CV *        cv;
558     /* Above here is the same for sub and format.  */
559     I32         olddepth;
560     AV          *savearray;
561 };
562
563
564 /* format context */
565 struct block_format {
566     OP *        retop;  /* op to execute on exit from sub */
567     I32         old_savestack_ix; /* saved PL_savestack_ix (also CXt_NULL) */
568     SSize_t     old_tmpsfloor; /* also used in CXt_NULL sort block */
569     /* Above here is the same for sub, format and eval.  */
570     PAD         *prevcomppad; /* the caller's PL_comppad */
571     CV *        cv;
572     /* Above here is the same for sub and format.  */
573     GV *        gv;
574     GV *        dfoutgv;
575 };
576
577 /* base for the next two macros. Don't use directly.
578  * The context frame holds a reference to the CV so that it can't be
579  * freed while we're executing it */
580
581 #define PUSHSUB_BASE(cx)                                                \
582         ENTRY_PROBE(CvNAMED(cv)                                         \
583                         ? HEK_KEY(CvNAME_HEK(cv))                       \
584                         : GvENAME(CvGV(cv)),                            \
585                 CopFILE((const COP *)CvSTART(cv)),                      \
586                 CopLINE((const COP *)CvSTART(cv)),                      \
587                 CopSTASHPV((const COP *)CvSTART(cv)));                  \
588                                                                         \
589         cx->blk_sub.cv = cv;                                            \
590         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
591         cx->blk_sub.prevcomppad = PL_comppad;                           \
592         cx->cx_type |= (hasargs) ? CXp_HASARGS : 0;                     \
593         cx->blk_sub.retop = NULL;                                       \
594         SvREFCNT_inc_simple_void_NN(cv);                                \
595         cx->blk_sub.old_tmpsfloor = PL_tmps_floor;                      \
596         PL_tmps_floor = PL_tmps_ix;
597
598 #define PUSHSUB_GET_LVALUE_MASK(func) \
599         /* If the context is indeterminate, then only the lvalue */     \
600         /* flags that the caller also has are applicable.        */     \
601         (                                                               \
602            (PL_op->op_flags & OPf_WANT)                                 \
603                ? OPpENTERSUB_LVAL_MASK                                  \
604                : !(PL_op->op_private & OPpENTERSUB_LVAL_MASK)           \
605                    ? 0 : (U8)func(aTHX)                                 \
606         )
607
608 #define PUSHSUB(cx)                                                     \
609     {                                                                   \
610         U8 phlags = PUSHSUB_GET_LVALUE_MASK(Perl_was_lvalue_sub);       \
611         PUSHSUB_BASE(cx)                                                \
612         cx->blk_u16 = PL_op->op_private &                               \
613                           (phlags|OPpDEREF);                            \
614     }
615
616 /* variant for use by OP_DBSTATE, where op_private holds hint bits */
617 #define PUSHSUB_DB(cx)                                                  \
618         PUSHSUB_BASE(cx)                                                \
619         cx->blk_u16 = 0;
620
621
622 #define PUSHFORMAT(cx, retop)                                           \
623         cx->blk_format.cv = cv;                                         \
624         cx->blk_format.gv = gv;                                         \
625         cx->blk_format.retop = (retop);                                 \
626         cx->blk_format.dfoutgv = PL_defoutgv;                           \
627         cx->blk_format.prevcomppad = PL_comppad;                        \
628         cx->blk_u16 = 0;                                                \
629         cx->blk_format.old_savestack_ix = PL_savestack_ix;                 \
630         cx->blk_format.old_tmpsfloor = PL_tmps_floor;                      \
631         PL_tmps_floor = PL_tmps_ix;                                     \
632         SvREFCNT_inc_simple_void_NN(cv);                                \
633         CvDEPTH(cv)++;                                                  \
634         SvREFCNT_inc_void(cx->blk_format.dfoutgv)
635
636 /* Restore old @_ */
637 #define POP_SAVEARRAY()                                         \
638     STMT_START {                                                        \
639         AV *av = GvAV(PL_defgv);                                        \
640         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
641         SvREFCNT_dec(av);                                               \
642     } STMT_END
643
644 /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
645  * leave any (a fast av_clear(ary), basically) */
646 #define CLEAR_ARGARRAY(ary) \
647     STMT_START {                                                        \
648         AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary);                      \
649         AvARRAY(ary) = AvALLOC(ary);                                    \
650         AvFILLp(ary) = -1;                                              \
651     } STMT_END
652
653 #define POPSUB(cx,sv)                                                   \
654     STMT_START {                                                        \
655         LEAVE_SCOPE(cx->blk_sub.old_savestack_ix);                      \
656         if (!(cx->blk_u16 & CxPOPSUB_DONE)) {                           \
657         cx->blk_u16 |= CxPOPSUB_DONE;                                   \
658         RETURN_PROBE(CvNAMED(cx->blk_sub.cv)                            \
659                         ? HEK_KEY(CvNAME_HEK(cx->blk_sub.cv))           \
660                         : GvENAME(CvGV(cx->blk_sub.cv)),                \
661                 CopFILE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
662                 CopLINE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
663                 CopSTASHPV((COP*)CvSTART((const CV*)cx->blk_sub.cv)));  \
664                                                                         \
665         if (CxHASARGS(cx)) {                                            \
666             AV *av;                                                     \
667             assert(AvARRAY(MUTABLE_AV(                                  \
668                 PadlistARRAY(CvPADLIST(cx->blk_sub.cv))[                \
669                         CvDEPTH(cx->blk_sub.cv)])) == PL_curpad);       \
670             POP_SAVEARRAY();                                            \
671             /* abandon @_ if it got reified */                          \
672             av = MUTABLE_AV(PAD_SVl(0));                                \
673             if (UNLIKELY(AvREAL(av)))                                   \
674                 clear_defarray(av, 0);                                  \
675             else {                                                      \
676                 CLEAR_ARGARRAY(av);                                     \
677             }                                                           \
678         }                                                               \
679         }                                                               \
680         PL_tmps_floor = cx->blk_sub.old_tmpsfloor;                      \
681         PL_comppad = cx->blk_sub.prevcomppad;                           \
682         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
683         sv = MUTABLE_SV(cx->blk_sub.cv);                                \
684         CvDEPTH((const CV*)sv) = cx->blk_sub.olddepth;                  \
685     } STMT_END
686
687 #define LEAVESUB(sv)                                                    \
688     STMT_START {                                                        \
689         SvREFCNT_dec(sv);                                               \
690     } STMT_END
691
692 #define POPFORMAT(cx)                                                   \
693     STMT_START {                                                        \
694         LEAVE_SCOPE(cx->blk_format.old_savestack_ix);                   \
695         if (!(cx->blk_u16 & CxPOPSUB_DONE)) {                           \
696         CV * const cv = cx->blk_format.cv;                              \
697         GV * const dfuot = cx->blk_format.dfoutgv;                      \
698         cx->blk_u16 |= CxPOPSUB_DONE;                                   \
699         PL_tmps_floor = cx->blk_format.old_tmpsfloor;                      \
700         setdefout(dfuot);                                               \
701         PL_comppad = cx->blk_format.prevcomppad;                        \
702         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
703         --CvDEPTH(cv);                                                  \
704         SvREFCNT_dec_NN(cx->blk_format.cv);                             \
705         SvREFCNT_dec_NN(dfuot);                                         \
706         }                                                               \
707     } STMT_END
708
709 /* eval context */
710 struct block_eval {
711     OP *        retop;  /* op to execute on exit from eval */
712     I32         old_savestack_ix; /* saved PL_savestack_ix (also CXt_NULL) */
713     SSize_t     old_tmpsfloor; /* also used in CXt_NULL sort block */
714     /* Above here is the same for sub, format and eval.  */
715     SV *        old_namesv;
716     OP *        old_eval_root;
717     SV *        cur_text;
718     CV *        cv;
719     JMPENV *    cur_top_env; /* value of PL_top_env when eval CX created */
720 };
721
722 /* If we ever need more than 512 op types, change the shift from 7.
723    blku_gimme is actually also only 2 bits, so could be merged with something.
724 */
725
726 #define CxOLD_IN_EVAL(cx)       (((cx)->blk_u16) & 0x7F)
727 #define CxOLD_OP_TYPE(cx)       (((cx)->blk_u16) >> 7)
728
729 #define PUSHEVAL(cx,n)                                                  \
730     STMT_START {                                                        \
731         assert(!(PL_in_eval & ~0x7F));                                  \
732         assert(!(PL_op->op_type & ~0x1FF));                             \
733         cx->blk_u16 = (PL_in_eval & 0x7F) | ((U16)PL_op->op_type << 7); \
734         cx->blk_eval.old_tmpsfloor = PL_tmps_floor;                     \
735         PL_tmps_floor = PL_tmps_ix;                                     \
736         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : NULL);            \
737         cx->blk_eval.old_eval_root = PL_eval_root;                      \
738         cx->blk_eval.cur_text = PL_parser ? PL_parser->linestr : NULL;  \
739         cx->blk_eval.cv = NULL; /* set by doeval(), as applicable */    \
740         cx->blk_eval.retop = NULL;                                      \
741         cx->blk_eval.cur_top_env = PL_top_env;                          \
742     } STMT_END
743
744 #define POPEVAL(cx)                                                     \
745     STMT_START {                                                        \
746         PL_in_eval = CxOLD_IN_EVAL(cx);                                 \
747         optype = CxOLD_OP_TYPE(cx);                                     \
748         PL_eval_root = cx->blk_eval.old_eval_root;                      \
749         if (cx->blk_eval.cur_text && SvSCREAM(cx->blk_eval.cur_text))   \
750             SvREFCNT_dec_NN(cx->blk_eval.cur_text);                     \
751         if (cx->blk_eval.old_namesv)                                    \
752             sv_2mortal(cx->blk_eval.old_namesv);                        \
753     } STMT_END
754
755 /* loop context */
756 struct block_loop {
757     I32         resetsp;
758     I32         old_savestack_ix; /* saved PL_savestack_ix (also CXt_NULL) */
759     LOOP *      my_op;  /* My op, that contains redo, next and last ops.  */
760     union {     /* different ways of locating the iteration variable */
761         SV      **svp; /* for lexicals: address of pad slot */
762         GV      *gv;   /* for package vars */
763     } itervar_u;
764     SV          *itersave; /* the original iteration var */
765     union {
766         struct { /* valid if type is LOOP_FOR or LOOP_PLAIN (but {NULL,0})*/
767             AV * ary; /* use the stack if this is NULL */
768             IV ix;
769         } ary;
770         struct { /* valid if type is LOOP_LAZYIV */
771             IV cur;
772             IV end;
773         } lazyiv;
774         struct { /* valid if type if LOOP_LAZYSV */
775             SV * cur;
776             SV * end; /* maxiumum value (or minimum in reverse) */
777         } lazysv;
778     } state_u;
779 #ifdef USE_ITHREADS
780     PAD *oldcomppad; /* needed to map itervar_u.svp during thread clone */
781 #endif
782 };
783
784 #define CxITERVAR(c)                                    \
785         (CxPADLOOP(c)                                   \
786             ? (c)->blk_loop.itervar_u.svp               \
787             : ((c)->cx_type & CXp_FOR_GV)               \
788                 ? &GvSV((c)->blk_loop.itervar_u.gv)     \
789                 : (SV **)&(c)->blk_loop.itervar_u.gv)
790
791 #define CxLABEL(c)      (0 + CopLABEL((c)->blk_oldcop))
792 #define CxLABEL_len(c,len)      (0 + CopLABEL_len((c)->blk_oldcop, len))
793 #define CxLABEL_len_flags(c,len,flags)  (0 + CopLABEL_len_flags((c)->blk_oldcop, len, flags))
794 #define CxHASARGS(c)    (((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
795 #define CxLVAL(c)       (0 + ((c)->blk_u16 & 0xff))
796 /* POPSUB has already been performed on this context frame */
797 #define CxPOPSUB_DONE 0x100
798
799
800 #define PUSHLOOP_PLAIN(cx, s)                                           \
801         cx->blk_loop.resetsp = s - PL_stack_base;                       \
802         cx->blk_loop.my_op = cLOOP;                                     \
803         cx->blk_loop.state_u.ary.ary = NULL;                            \
804         cx->blk_loop.state_u.ary.ix = 0;                                \
805         cx->blk_loop.old_savestack_ix = PL_savestack_ix;                \
806         cx->blk_loop.itervar_u.svp = NULL;                              \
807         cx->blk_loop.itersave = NULL;
808
809 #ifdef USE_ITHREADS
810 #  define PUSHLOOP_FOR_setpad(c) (c)->blk_loop.oldcomppad = PL_comppad
811 #else
812 #  define PUSHLOOP_FOR_setpad(c) NOOP
813 #endif
814
815 #define PUSHLOOP_FOR(cx, ivar, isave, s)                                \
816         cx->blk_loop.resetsp = s - PL_stack_base;                       \
817         cx->blk_loop.my_op = cLOOP;                                     \
818         cx->blk_loop.state_u.ary.ary = NULL;                            \
819         cx->blk_loop.state_u.ary.ix = 0;                                \
820         cx->blk_loop.itervar_u.svp = (SV**)(ivar);                      \
821         cx->blk_loop.old_savestack_ix = PL_savestack_ix;                \
822         cx->blk_loop.itersave = isave;                                  \
823         PUSHLOOP_FOR_setpad(cx);
824
825 #define POPLOOP(cx)                                                     \
826         LEAVE_SCOPE(cx->blk_loop.old_savestack_ix);                     \
827         if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {                            \
828             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.cur);           \
829             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.end);           \
830         }                                                               \
831         else if (CxTYPE(cx) == CXt_LOOP_FOR)                            \
832             SvREFCNT_dec(cx->blk_loop.state_u.ary.ary);                 \
833         if (cx->cx_type & (CXp_FOR_PAD|CXp_FOR_GV)) {                   \
834             SV **svp = (cx)->blk_loop.itervar_u.svp;                    \
835             SV *cursv;                                                  \
836             if ((cx->cx_type & CXp_FOR_GV)) {                           \
837                 svp = &GvSV((GV*)svp);                                  \
838                 cursv = *svp;                                           \
839                 *svp = cx->blk_loop.itersave;                           \
840             }                                                           \
841             else {                                                      \
842                 cursv = *svp;                                           \
843                 *svp = cx->blk_loop.itersave;                           \
844             }                                                           \
845             SvREFCNT_dec(cursv);                                        \
846         }
847
848 /* given/when context */
849 struct block_givwhen {
850         OP *leave_op;
851 };
852
853 #define PUSHGIVEN(cx)                                                   \
854         cx->blk_givwhen.leave_op = cLOGOP->op_other;
855
856 #define PUSHWHEN PUSHGIVEN
857
858 /* context common to subroutines, evals and loops */
859 struct block {
860     U8          blku_type;      /* what kind of context this is */
861     U8          blku_gimme;     /* is this block running in list context? */
862     U16         blku_u16;       /* used by block_sub and block_eval (so far) */
863     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
864     COP *       blku_oldcop;    /* old curcop pointer */
865     I32         blku_oldmarksp; /* mark stack index */
866     I32         blku_oldscopesp;        /* scope stack index */
867     PMOP *      blku_oldpm;     /* values of pattern match vars */
868
869     union {
870         struct block_sub        blku_sub;
871         struct block_format     blku_format;
872         struct block_eval       blku_eval;
873         struct block_loop       blku_loop;
874         struct block_givwhen    blku_givwhen;
875     } blk_u;
876 };
877 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
878 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
879 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
880 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
881 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
882 #define blk_gimme       cx_u.cx_blk.blku_gimme
883 #define blk_u16         cx_u.cx_blk.blku_u16
884 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
885 #define blk_format      cx_u.cx_blk.blk_u.blku_format
886 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
887 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
888 #define blk_givwhen     cx_u.cx_blk.blk_u.blku_givwhen
889
890 #define DEBUG_CX(action)                                                \
891     DEBUG_l(                                                            \
892         Perl_deb(aTHX_ "CX %ld %s %s (scope %ld,%ld) at %s:%d\n",       \
893                     (long)cxstack_ix,                                   \
894                     action,                                             \
895                     PL_block_type[CxTYPE(&cxstack[cxstack_ix])],        \
896                     (long)PL_scopestack_ix,                             \
897                     (long)(cxstack[cxstack_ix].blk_oldscopesp),         \
898                     __FILE__, __LINE__));
899
900 /* Enter a block. */
901 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
902         cx->cx_type             = t,                                    \
903         cx->blk_oldsp           = sp - PL_stack_base,                   \
904         cx->blk_oldcop          = PL_curcop,                            \
905         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
906         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
907         cx->blk_oldpm           = PL_curpm,                             \
908         cx->blk_gimme           = (U8)gimme;                            \
909         DEBUG_CX("PUSH");
910
911 /* Exit a block (RETURN and LAST). */
912 #define POPBLOCK(cx,pm)                                                 \
913         DEBUG_CX("POP");                                                \
914         cx = &cxstack[cxstack_ix--],                                    \
915         newsp            = PL_stack_base + cx->blk_oldsp,               \
916         PL_curcop        = cx->blk_oldcop,                              \
917         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
918         PL_scopestack_ix = cx->blk_oldscopesp,                          \
919         pm               = cx->blk_oldpm,                               \
920         gimme            = cx->blk_gimme;
921
922 /* Continue a block elsewhere (NEXT and REDO). */
923 #define TOPBLOCK(cx)                                                    \
924         DEBUG_CX("TOP");                                                \
925         cx  = &cxstack[cxstack_ix],                                     \
926         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
927         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
928         PL_scopestack_ix = cx->blk_oldscopesp,                          \
929         PL_curpm         = cx->blk_oldpm;
930
931 /* substitution context */
932 struct subst {
933     U8          sbu_type;       /* what kind of context this is */
934     U8          sbu_rflags;
935     U16         sbu_rxtainted;  /* matches struct block */
936     I32         sbu_oldsave;
937     SSize_t     sbu_iters;
938     SSize_t     sbu_maxiters;
939     char *      sbu_orig;
940     SV *        sbu_dstr;
941     SV *        sbu_targ;
942     char *      sbu_s;
943     char *      sbu_m;
944     char *      sbu_strend;
945     void *      sbu_rxres;
946     REGEXP *    sbu_rx;
947 };
948 #define sb_iters        cx_u.cx_subst.sbu_iters
949 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
950 #define sb_rflags       cx_u.cx_subst.sbu_rflags
951 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
952 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
953 #define sb_orig         cx_u.cx_subst.sbu_orig
954 #define sb_dstr         cx_u.cx_subst.sbu_dstr
955 #define sb_targ         cx_u.cx_subst.sbu_targ
956 #define sb_s            cx_u.cx_subst.sbu_s
957 #define sb_m            cx_u.cx_subst.sbu_m
958 #define sb_strend       cx_u.cx_subst.sbu_strend
959 #define sb_rxres        cx_u.cx_subst.sbu_rxres
960 #define sb_rx           cx_u.cx_subst.sbu_rx
961
962 #ifdef PERL_CORE
963 #  define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],               \
964         cx->sb_iters            = iters,                                \
965         cx->sb_maxiters         = maxiters,                             \
966         cx->sb_rflags           = r_flags,                              \
967         cx->sb_oldsave          = oldsave,                              \
968         cx->sb_rxtainted        = rxtainted,                            \
969         cx->sb_orig             = orig,                                 \
970         cx->sb_dstr             = dstr,                                 \
971         cx->sb_targ             = targ,                                 \
972         cx->sb_s                = s,                                    \
973         cx->sb_m                = m,                                    \
974         cx->sb_strend           = strend,                               \
975         cx->sb_rxres            = NULL,                                 \
976         cx->sb_rx               = rx,                                   \
977         cx->cx_type             = CXt_SUBST | (once ? CXp_ONCE : 0);    \
978         rxres_save(&cx->sb_rxres, rx);                                  \
979         (void)ReREFCNT_inc(rx);                                         \
980         SvREFCNT_inc_void_NN(targ)
981
982 #  define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                     \
983         rxres_free(&cx->sb_rxres);                                      \
984         ReREFCNT_dec(cx->sb_rx);                                        \
985         SvREFCNT_dec_NN(cx->sb_targ)
986 #endif
987
988 #define CxONCE(cx)              ((cx)->cx_type & CXp_ONCE)
989
990 struct context {
991     union {
992         struct block    cx_blk;
993         struct subst    cx_subst;
994     } cx_u;
995 };
996 #define cx_type cx_u.cx_subst.sbu_type
997
998 /* If you re-order these, there is also an array of uppercase names in perl.h
999    and a static array of context names in pp_ctl.c  */
1000 #define CXTYPEMASK      0xf
1001 #define CXt_NULL        0
1002 #define CXt_WHEN        1
1003 #define CXt_BLOCK       2
1004 /* When micro-optimising :-) keep GIVEN next to the LOOPs, as these 5 share a
1005    jump table in pp_ctl.c
1006    The first 4 don't have a 'case' in at least one switch statement in pp_ctl.c
1007 */
1008 #define CXt_GIVEN       3
1009 /* This is first so that CXt_LOOP_FOR|CXt_LOOP_LAZYIV is CXt_LOOP_LAZYIV */
1010 #define CXt_LOOP_FOR    4
1011 #define CXt_LOOP_PLAIN  5
1012 #define CXt_LOOP_LAZYSV 6
1013 #define CXt_LOOP_LAZYIV 7
1014 #define CXt_SUB         8
1015 #define CXt_FORMAT      9
1016 #define CXt_EVAL       10
1017 #define CXt_SUBST      11
1018 /* SUBST doesn't feature in all switch statements.  */
1019
1020 /* private flags for CXt_SUB and CXt_NULL
1021    However, this is checked in many places which do not check the type, so
1022    this bit needs to be kept clear for most everything else. For reasons I
1023    haven't investigated, it can coexist with CXp_FOR_DEF */
1024 #define CXp_MULTICALL   0x10    /* part of a multicall (so don't
1025                                    tear down context on exit). */ 
1026
1027 /* private flags for CXt_SUB and CXt_FORMAT */
1028 #define CXp_HASARGS     0x20
1029 #define CXp_SUB_RE      0x40    /* code called within regex, i.e. (?{}) */
1030 #define CXp_SUB_RE_FAKE 0x80    /* fake sub CX for (?{}) in current scope */
1031
1032 /* private flags for CXt_EVAL */
1033 #define CXp_REAL        0x20    /* truly eval'', not a lookalike */
1034 #define CXp_TRYBLOCK    0x40    /* eval{}, not eval'' or similar */
1035
1036 /* private flags for CXt_LOOP */
1037 #define CXp_FOR_DEF     0x10    /* foreach using $_ */
1038 #define CXp_FOR_LVREF   0x20    /* foreach using \$var */
1039 #define CXp_FOR_GV      0x40    /* foreach using package var */
1040 #define CXp_FOR_PAD     0x80    /* foreach using lexical var */
1041 #define CxPADLOOP(c)    ((c)->cx_type & CXp_FOR_PAD)
1042
1043 /* private flags for CXt_SUBST */
1044 #define CXp_ONCE        0x10    /* What was sbu_once in struct subst */
1045
1046 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
1047 #define CxTYPE_is_LOOP(c)       (((c)->cx_type & 0xC) == 0x4)
1048 #define CxMULTICALL(c)  (((c)->cx_type & CXp_MULTICALL)                 \
1049                          == CXp_MULTICALL)
1050 #define CxREALEVAL(c)   (((c)->cx_type & (CXTYPEMASK|CXp_REAL))         \
1051                          == (CXt_EVAL|CXp_REAL))
1052 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXTYPEMASK|CXp_TRYBLOCK))     \
1053                          == (CXt_EVAL|CXp_TRYBLOCK))
1054 #define CxFOREACH(c)    (CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN)
1055 #define CxFOREACHDEF(c) ((CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN) \
1056                          && ((c)->cx_type & CXp_FOR_DEF))
1057
1058 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
1059
1060 /* 
1061 =head1 "Gimme" Values
1062 */
1063
1064 /*
1065 =for apidoc AmU||G_SCALAR
1066 Used to indicate scalar context.  See C<L</GIMME_V>>, C<L</GIMME>>, and
1067 L<perlcall>.
1068
1069 =for apidoc AmU||G_ARRAY
1070 Used to indicate list context.  See C<L</GIMME_V>>, C<L</GIMME>> and
1071 L<perlcall>.
1072
1073 =for apidoc AmU||G_VOID
1074 Used to indicate void context.  See C<L</GIMME_V>> and L<perlcall>.
1075
1076 =for apidoc AmU||G_DISCARD
1077 Indicates that arguments returned from a callback should be discarded.  See
1078 L<perlcall>.
1079
1080 =for apidoc AmU||G_EVAL
1081
1082 Used to force a Perl C<eval> wrapper around a callback.  See
1083 L<perlcall>.
1084
1085 =for apidoc AmU||G_NOARGS
1086
1087 Indicates that no arguments are being sent to a callback.  See
1088 L<perlcall>.
1089
1090 =cut
1091 */
1092
1093 #define G_SCALAR        2
1094 #define G_ARRAY         3
1095 #define G_VOID          1
1096 #define G_WANT          3
1097
1098 /* extra flags for Perl_call_* routines */
1099 #define G_DISCARD       4       /* Call FREETMPS.
1100                                    Don't change this without consulting the
1101                                    hash actions codes defined in hv.h */
1102 #define G_EVAL          8       /* Assume eval {} around subroutine call. */
1103 #define G_NOARGS       16       /* Don't construct a @_ array. */
1104 #define G_KEEPERR      32       /* Warn for errors, don't overwrite $@ */
1105 #define G_NODEBUG      64       /* Disable debugging at toplevel.  */
1106 #define G_METHOD      128       /* Calling method. */
1107 #define G_FAKINGEVAL  256       /* Faking an eval context for call_sv or
1108                                    fold_constants. */
1109 #define G_UNDEF_FILL  512       /* Fill the stack with &PL_sv_undef
1110                                    A special case for UNSHIFT in
1111                                    Perl_magic_methcall().  */
1112 #define G_WRITING_TO_STDERR 1024 /* Perl_write_to_stderr() is calling
1113                                     Perl_magic_methcall().  */
1114 #define G_RE_REPARSING 0x800     /* compiling a run-time /(?{..})/ */
1115 #define G_METHOD_NAMED 4096     /* calling named method, eg without :: or ' */
1116
1117 /* flag bits for PL_in_eval */
1118 #define EVAL_NULL       0       /* not in an eval */
1119 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
1120 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
1121 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
1122 #define EVAL_INREQUIRE  8       /* The code is being required. */
1123 #define EVAL_RE_REPARSING 0x10  /* eval_sv() called with G_RE_REPARSING */
1124
1125 /* Support for switching (stack and block) contexts.
1126  * This ensures magic doesn't invalidate local stack and cx pointers.
1127  */
1128
1129 #define PERLSI_UNKNOWN          -1
1130 #define PERLSI_UNDEF            0
1131 #define PERLSI_MAIN             1
1132 #define PERLSI_MAGIC            2
1133 #define PERLSI_SORT             3
1134 #define PERLSI_SIGNAL           4
1135 #define PERLSI_OVERLOAD         5
1136 #define PERLSI_DESTROY          6
1137 #define PERLSI_WARNHOOK         7
1138 #define PERLSI_DIEHOOK          8
1139 #define PERLSI_REQUIRE          9
1140 #define PERLSI_MULTICALL       10
1141
1142 struct stackinfo {
1143     AV *                si_stack;       /* stack for current runlevel */
1144     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
1145     struct stackinfo *  si_prev;
1146     struct stackinfo *  si_next;
1147     I32                 si_cxix;        /* current context index */
1148     I32                 si_cxmax;       /* maximum allocated index */
1149     I32                 si_type;        /* type of runlevel */
1150     I32                 si_markoff;     /* offset where markstack begins for us.
1151                                          * currently used only with DEBUGGING,
1152                                          * but not #ifdef-ed for bincompat */
1153 };
1154
1155 typedef struct stackinfo PERL_SI;
1156
1157 #define cxstack         (PL_curstackinfo->si_cxstack)
1158 #define cxstack_ix      (PL_curstackinfo->si_cxix)
1159 #define cxstack_max     (PL_curstackinfo->si_cxmax)
1160
1161 #ifdef DEBUGGING
1162 #  define       SET_MARK_OFFSET \
1163     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
1164 #else
1165 #  define       SET_MARK_OFFSET NOOP
1166 #endif
1167
1168 #define PUSHSTACKi(type) \
1169     STMT_START {                                                        \
1170         PERL_SI *next = PL_curstackinfo->si_next;                       \
1171         DEBUG_l({                                                       \
1172             int i = 0; PERL_SI *p = PL_curstackinfo;                    \
1173             while (p) { i++; p = p->si_prev; }                          \
1174             Perl_deb(aTHX_ "push STACKINFO %d at %s:%d\n",              \
1175                          i, __FILE__, __LINE__);})                      \
1176         if (!next) {                                                    \
1177             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
1178             next->si_prev = PL_curstackinfo;                            \
1179             PL_curstackinfo->si_next = next;                            \
1180         }                                                               \
1181         next->si_type = type;                                           \
1182         next->si_cxix = -1;                                             \
1183         AvFILLp(next->si_stack) = 0;                                    \
1184         SWITCHSTACK(PL_curstack,next->si_stack);                        \
1185         PL_curstackinfo = next;                                         \
1186         SET_MARK_OFFSET;                                                \
1187     } STMT_END
1188
1189 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
1190
1191 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
1192  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
1193 #define POPSTACK \
1194     STMT_START {                                                        \
1195         dSP;                                                            \
1196         PERL_SI * const prev = PL_curstackinfo->si_prev;                \
1197         DEBUG_l({                                                       \
1198             int i = -1; PERL_SI *p = PL_curstackinfo;                   \
1199             while (p) { i++; p = p->si_prev; }                          \
1200             Perl_deb(aTHX_ "pop  STACKINFO %d at %s:%d\n",              \
1201                          i, __FILE__, __LINE__);})                      \
1202         if (!prev) {                                                    \
1203             Perl_croak_popstack();                                      \
1204         }                                                               \
1205         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
1206         /* don't free prev here, free them all at the END{} */          \
1207         PL_curstackinfo = prev;                                         \
1208     } STMT_END
1209
1210 #define POPSTACK_TO(s) \
1211     STMT_START {                                                        \
1212         while (PL_curstack != s) {                                      \
1213             dounwind(-1);                                               \
1214             POPSTACK;                                                   \
1215         }                                                               \
1216     } STMT_END
1217
1218 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
1219 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
1220
1221 /*
1222 =head1 Multicall Functions
1223
1224 =for apidoc Ams||dMULTICALL
1225 Declare local variables for a multicall.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1226
1227 =for apidoc Ams||PUSH_MULTICALL
1228 Opening bracket for a lightweight callback.
1229 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1230
1231 =for apidoc Ams||MULTICALL
1232 Make a lightweight callback.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1233
1234 =for apidoc Ams||POP_MULTICALL
1235 Closing bracket for a lightweight callback.
1236 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1237
1238 =cut
1239 */
1240
1241 #define dMULTICALL \
1242     SV **newsp;                 /* set by POPBLOCK */                   \
1243     PERL_CONTEXT *cx;                                                   \
1244     CV *multicall_cv;                                                   \
1245     OP *multicall_cop;                                                  \
1246     bool multicall_oldcatch;                                            \
1247     U8 hasargs = 0              /* used by PUSHSUB */
1248
1249 #define PUSH_MULTICALL(the_cv) \
1250     PUSH_MULTICALL_FLAGS(the_cv, 0)
1251
1252 /* Like PUSH_MULTICALL, but allows you to specify extra flags
1253  * for the CX stack entry (this isn't part of the public API) */
1254
1255 #define PUSH_MULTICALL_FLAGS(the_cv, flags) \
1256     STMT_START {                                                        \
1257         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1258         CV * const cv = _nOnclAshIngNamE_;                              \
1259         PADLIST * const padlist = CvPADLIST(cv);                        \
1260         multicall_oldcatch = CATCH_GET;                                 \
1261         CATCH_SET(TRUE);                                                \
1262         PUSHSTACKi(PERLSI_MULTICALL);                                   \
1263         PUSHBLOCK(cx, (CXt_SUB|CXp_MULTICALL|flags), PL_stack_sp);      \
1264         PUSHSUB(cx);                                                    \
1265         cx->blk_sub.old_savestack_ix = PL_savestack_ix;                  \
1266         SAVEVPTR(PL_op);                                                \
1267         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1268             CvDEPTH(cv)++;                                              \
1269         if (CvDEPTH(cv) >= 2) {                                         \
1270             PERL_STACK_OVERFLOW_CHECK();                                \
1271             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1272         }                                                               \
1273         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1274         multicall_cv = cv;                                              \
1275         multicall_cop = CvSTART(cv);                                    \
1276     } STMT_END
1277
1278 #define MULTICALL \
1279     STMT_START {                                                        \
1280         PL_op = multicall_cop;                                          \
1281         CALLRUNOPS(aTHX);                                               \
1282     } STMT_END
1283
1284 #define POP_MULTICALL \
1285     STMT_START {                                                        \
1286         cx = &cxstack[cxstack_ix];                                      \
1287         CvDEPTH(multicall_cv) = cx->blk_sub.olddepth;                   \
1288         LEAVESUB(multicall_cv);                                         \
1289         POPBLOCK(cx,PL_curpm);                                          \
1290         /* includes partial unrolled POPSUB(): */                       \
1291         LEAVE_SCOPE(cx->blk_sub.old_savestack_ix);                      \
1292         PL_comppad = cx->blk_sub.prevcomppad;                           \
1293         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
1294         POPSTACK;                                                       \
1295         CATCH_SET(multicall_oldcatch);                                  \
1296         SPAGAIN;                                                        \
1297     } STMT_END
1298
1299 /* Change the CV of an already-pushed MULTICALL CxSUB block.
1300  * (this isn't part of the public API) */
1301
1302 #define CHANGE_MULTICALL_FLAGS(the_cv, flags) \
1303     STMT_START {                                                        \
1304         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1305         CV * const cv = _nOnclAshIngNamE_;                              \
1306         PADLIST * const padlist = CvPADLIST(cv);                        \
1307         cx = &cxstack[cxstack_ix];                                      \
1308         assert(cx->cx_type & CXp_MULTICALL);                            \
1309         CvDEPTH(multicall_cv) = cx->blk_sub.olddepth;                   \
1310         LEAVESUB(multicall_cv);                                         \
1311         cx->cx_type = (CXt_SUB|CXp_MULTICALL|flags);                    \
1312         {                                                               \
1313             /* save a few things that we don't want PUSHSUB to zap */   \
1314             PAD * const prevcomppad = cx->blk_sub.prevcomppad;          \
1315             SSize_t old_floor = cx->blk_sub.old_tmpsfloor;              \
1316             SSize_t floor = PL_tmps_floor;                              \
1317             PUSHSUB(cx);                                                \
1318             /* undo the stuff that PUSHSUB zapped */                    \
1319             cx->blk_sub.prevcomppad = prevcomppad ;                     \
1320             cx->blk_sub.old_tmpsfloor = old_floor;                      \
1321             PL_tmps_floor = floor;                                      \
1322         }                                                               \
1323         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1324             CvDEPTH(cv)++;                                              \
1325         if (CvDEPTH(cv) >= 2) {                                         \
1326             PERL_STACK_OVERFLOW_CHECK();                                \
1327             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1328         }                                                               \
1329         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1330         multicall_cv = cv;                                              \
1331         multicall_cop = CvSTART(cv);                                    \
1332     } STMT_END
1333 /*
1334  * ex: set ts=8 sts=4 sw=4 et:
1335  */