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Add itersave field to LOOP context struct
[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)->blk_loop.itervar_u.svp                               \
788                 ? isGV((c)->blk_loop.itervar_u.gv)                      \
789                     ? &GvSV((c)->blk_loop.itervar_u.gv)                 \
790                     : (SV **)&(c)->blk_loop.itervar_u.gv                \
791                 : (SV**)NULL)
792
793 #define CxLABEL(c)      (0 + CopLABEL((c)->blk_oldcop))
794 #define CxLABEL_len(c,len)      (0 + CopLABEL_len((c)->blk_oldcop, len))
795 #define CxLABEL_len_flags(c,len,flags)  (0 + CopLABEL_len_flags((c)->blk_oldcop, len, flags))
796 #define CxHASARGS(c)    (((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
797 #define CxLVAL(c)       (0 + ((c)->blk_u16 & 0xff))
798 /* POPSUB has already been performed on this context frame */
799 #define CxPOPSUB_DONE 0x100
800
801
802 #define PUSHLOOP_PLAIN(cx, s)                                           \
803         cx->blk_loop.resetsp = s - PL_stack_base;                       \
804         cx->blk_loop.my_op = cLOOP;                                     \
805         cx->blk_loop.state_u.ary.ary = NULL;                            \
806         cx->blk_loop.state_u.ary.ix = 0;                                \
807         cx->blk_loop.old_savestack_ix = PL_savestack_ix;                \
808         cx->blk_loop.itervar_u.svp = NULL;                              \
809         cx->blk_loop.itersave = NULL;
810
811 #ifdef USE_ITHREADS
812 #  define PUSHLOOP_FOR_setpad(c) (c)->blk_loop.oldcomppad = PL_comppad
813 #else
814 #  define PUSHLOOP_FOR_setpad(c) NOOP
815 #endif
816
817 #define PUSHLOOP_FOR(cx, ivar, isave, s)                                \
818         cx->blk_loop.resetsp = s - PL_stack_base;                       \
819         cx->blk_loop.my_op = cLOOP;                                     \
820         cx->blk_loop.state_u.ary.ary = NULL;                            \
821         cx->blk_loop.state_u.ary.ix = 0;                                \
822         cx->blk_loop.itervar_u.svp = (SV**)(ivar);                      \
823         cx->blk_loop.old_savestack_ix = PL_savestack_ix;                \
824         cx->blk_loop.itersave = isave;                                  \
825         PUSHLOOP_FOR_setpad(cx);
826
827 #define POPLOOP(cx)                                                     \
828         LEAVE_SCOPE(cx->blk_loop.old_savestack_ix);                     \
829         if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {                            \
830             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.cur);           \
831             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.end);           \
832         }                                                               \
833         else if (CxTYPE(cx) == CXt_LOOP_FOR)                            \
834             SvREFCNT_dec(cx->blk_loop.state_u.ary.ary);                 \
835         if (cx->blk_loop.itersave) {                                    \
836             SV **svp = (cx)->blk_loop.itervar_u.svp;                    \
837             SV *cursv;                                                  \
838             if (isGV((GV*)svp)) {                                       \
839                 svp = &GvSV((GV*)svp);                                  \
840                 cursv = *svp;                                           \
841                 *svp = cx->blk_loop.itersave;                           \
842                 SvREFCNT_dec_NN(cx->blk_loop.itersave);                 \
843             }                                                           \
844             else {                                                      \
845                 cursv = *svp;                                           \
846                 *svp = cx->blk_loop.itersave;                           \
847             }                                                           \
848             /* delayed rc-- in case of "for $x (...) { return $x }" */  \
849             sv_2mortal(cursv);                                          \
850         }                                                               \
851
852 /* given/when context */
853 struct block_givwhen {
854         OP *leave_op;
855 };
856
857 #define PUSHGIVEN(cx)                                                   \
858         cx->blk_givwhen.leave_op = cLOGOP->op_other;
859
860 #define PUSHWHEN PUSHGIVEN
861
862 /* context common to subroutines, evals and loops */
863 struct block {
864     U8          blku_type;      /* what kind of context this is */
865     U8          blku_gimme;     /* is this block running in list context? */
866     U16         blku_u16;       /* used by block_sub and block_eval (so far) */
867     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
868     COP *       blku_oldcop;    /* old curcop pointer */
869     I32         blku_oldmarksp; /* mark stack index */
870     I32         blku_oldscopesp;        /* scope stack index */
871     PMOP *      blku_oldpm;     /* values of pattern match vars */
872
873     union {
874         struct block_sub        blku_sub;
875         struct block_format     blku_format;
876         struct block_eval       blku_eval;
877         struct block_loop       blku_loop;
878         struct block_givwhen    blku_givwhen;
879     } blk_u;
880 };
881 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
882 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
883 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
884 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
885 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
886 #define blk_gimme       cx_u.cx_blk.blku_gimme
887 #define blk_u16         cx_u.cx_blk.blku_u16
888 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
889 #define blk_format      cx_u.cx_blk.blk_u.blku_format
890 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
891 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
892 #define blk_givwhen     cx_u.cx_blk.blk_u.blku_givwhen
893
894 #define DEBUG_CX(action)                                                \
895     DEBUG_l(                                                            \
896         Perl_deb(aTHX_ "CX %ld %s %s (scope %ld,%ld) at %s:%d\n",       \
897                     (long)cxstack_ix,                                   \
898                     action,                                             \
899                     PL_block_type[CxTYPE(&cxstack[cxstack_ix])],        \
900                     (long)PL_scopestack_ix,                             \
901                     (long)(cxstack[cxstack_ix].blk_oldscopesp),         \
902                     __FILE__, __LINE__));
903
904 /* Enter a block. */
905 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
906         cx->cx_type             = t,                                    \
907         cx->blk_oldsp           = sp - PL_stack_base,                   \
908         cx->blk_oldcop          = PL_curcop,                            \
909         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
910         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
911         cx->blk_oldpm           = PL_curpm,                             \
912         cx->blk_gimme           = (U8)gimme;                            \
913         DEBUG_CX("PUSH");
914
915 /* Exit a block (RETURN and LAST). */
916 #define POPBLOCK(cx,pm)                                                 \
917         DEBUG_CX("POP");                                                \
918         cx = &cxstack[cxstack_ix--],                                    \
919         newsp            = PL_stack_base + cx->blk_oldsp,               \
920         PL_curcop        = cx->blk_oldcop,                              \
921         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
922         PL_scopestack_ix = cx->blk_oldscopesp,                          \
923         pm               = cx->blk_oldpm,                               \
924         gimme            = cx->blk_gimme;
925
926 /* Continue a block elsewhere (NEXT and REDO). */
927 #define TOPBLOCK(cx)                                                    \
928         DEBUG_CX("TOP");                                                \
929         cx  = &cxstack[cxstack_ix],                                     \
930         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
931         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
932         PL_scopestack_ix = cx->blk_oldscopesp,                          \
933         PL_curpm         = cx->blk_oldpm;
934
935 /* substitution context */
936 struct subst {
937     U8          sbu_type;       /* what kind of context this is */
938     U8          sbu_rflags;
939     U16         sbu_rxtainted;  /* matches struct block */
940     I32         sbu_oldsave;
941     SSize_t     sbu_iters;
942     SSize_t     sbu_maxiters;
943     char *      sbu_orig;
944     SV *        sbu_dstr;
945     SV *        sbu_targ;
946     char *      sbu_s;
947     char *      sbu_m;
948     char *      sbu_strend;
949     void *      sbu_rxres;
950     REGEXP *    sbu_rx;
951 };
952 #define sb_iters        cx_u.cx_subst.sbu_iters
953 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
954 #define sb_rflags       cx_u.cx_subst.sbu_rflags
955 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
956 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
957 #define sb_orig         cx_u.cx_subst.sbu_orig
958 #define sb_dstr         cx_u.cx_subst.sbu_dstr
959 #define sb_targ         cx_u.cx_subst.sbu_targ
960 #define sb_s            cx_u.cx_subst.sbu_s
961 #define sb_m            cx_u.cx_subst.sbu_m
962 #define sb_strend       cx_u.cx_subst.sbu_strend
963 #define sb_rxres        cx_u.cx_subst.sbu_rxres
964 #define sb_rx           cx_u.cx_subst.sbu_rx
965
966 #ifdef PERL_CORE
967 #  define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],               \
968         cx->sb_iters            = iters,                                \
969         cx->sb_maxiters         = maxiters,                             \
970         cx->sb_rflags           = r_flags,                              \
971         cx->sb_oldsave          = oldsave,                              \
972         cx->sb_rxtainted        = rxtainted,                            \
973         cx->sb_orig             = orig,                                 \
974         cx->sb_dstr             = dstr,                                 \
975         cx->sb_targ             = targ,                                 \
976         cx->sb_s                = s,                                    \
977         cx->sb_m                = m,                                    \
978         cx->sb_strend           = strend,                               \
979         cx->sb_rxres            = NULL,                                 \
980         cx->sb_rx               = rx,                                   \
981         cx->cx_type             = CXt_SUBST | (once ? CXp_ONCE : 0);    \
982         rxres_save(&cx->sb_rxres, rx);                                  \
983         (void)ReREFCNT_inc(rx);                                         \
984         SvREFCNT_inc_void_NN(targ)
985
986 #  define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                     \
987         rxres_free(&cx->sb_rxres);                                      \
988         ReREFCNT_dec(cx->sb_rx);                                        \
989         SvREFCNT_dec_NN(cx->sb_targ)
990 #endif
991
992 #define CxONCE(cx)              ((cx)->cx_type & CXp_ONCE)
993
994 struct context {
995     union {
996         struct block    cx_blk;
997         struct subst    cx_subst;
998     } cx_u;
999 };
1000 #define cx_type cx_u.cx_subst.sbu_type
1001
1002 /* If you re-order these, there is also an array of uppercase names in perl.h
1003    and a static array of context names in pp_ctl.c  */
1004 #define CXTYPEMASK      0xf
1005 #define CXt_NULL        0
1006 #define CXt_WHEN        1
1007 #define CXt_BLOCK       2
1008 /* When micro-optimising :-) keep GIVEN next to the LOOPs, as these 5 share a
1009    jump table in pp_ctl.c
1010    The first 4 don't have a 'case' in at least one switch statement in pp_ctl.c
1011 */
1012 #define CXt_GIVEN       3
1013 /* This is first so that CXt_LOOP_FOR|CXt_LOOP_LAZYIV is CXt_LOOP_LAZYIV */
1014 #define CXt_LOOP_FOR    4
1015 #define CXt_LOOP_PLAIN  5
1016 #define CXt_LOOP_LAZYSV 6
1017 #define CXt_LOOP_LAZYIV 7
1018 #define CXt_SUB         8
1019 #define CXt_FORMAT      9
1020 #define CXt_EVAL       10
1021 #define CXt_SUBST      11
1022 /* SUBST doesn't feature in all switch statements.  */
1023
1024 /* private flags for CXt_SUB and CXt_NULL
1025    However, this is checked in many places which do not check the type, so
1026    this bit needs to be kept clear for most everything else. For reasons I
1027    haven't investigated, it can coexist with CXp_FOR_DEF */
1028 #define CXp_MULTICALL   0x10    /* part of a multicall (so don't
1029                                    tear down context on exit). */ 
1030
1031 /* private flags for CXt_SUB and CXt_FORMAT */
1032 #define CXp_HASARGS     0x20
1033 #define CXp_SUB_RE      0x40    /* code called within regex, i.e. (?{}) */
1034 #define CXp_SUB_RE_FAKE 0x80    /* fake sub CX for (?{}) in current scope */
1035
1036 /* private flags for CXt_EVAL */
1037 #define CXp_REAL        0x20    /* truly eval'', not a lookalike */
1038 #define CXp_TRYBLOCK    0x40    /* eval{}, not eval'' or similar */
1039
1040 /* private flags for CXt_LOOP */
1041 #define CXp_FOR_DEF     0x10    /* foreach using $_ */
1042 #define CXp_FOR_LVREF   0x20    /* foreach using \$var */
1043 #define CxPADLOOP(c)    ((c)->blk_loop.my_op->op_targ)
1044
1045 /* private flags for CXt_SUBST */
1046 #define CXp_ONCE        0x10    /* What was sbu_once in struct subst */
1047
1048 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
1049 #define CxTYPE_is_LOOP(c)       (((c)->cx_type & 0xC) == 0x4)
1050 #define CxMULTICALL(c)  (((c)->cx_type & CXp_MULTICALL)                 \
1051                          == CXp_MULTICALL)
1052 #define CxREALEVAL(c)   (((c)->cx_type & (CXTYPEMASK|CXp_REAL))         \
1053                          == (CXt_EVAL|CXp_REAL))
1054 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXTYPEMASK|CXp_TRYBLOCK))     \
1055                          == (CXt_EVAL|CXp_TRYBLOCK))
1056 #define CxFOREACH(c)    (CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN)
1057 #define CxFOREACHDEF(c) ((CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN) \
1058                          && ((c)->cx_type & CXp_FOR_DEF))
1059
1060 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
1061
1062 /* 
1063 =head1 "Gimme" Values
1064 */
1065
1066 /*
1067 =for apidoc AmU||G_SCALAR
1068 Used to indicate scalar context.  See C<L</GIMME_V>>, C<L</GIMME>>, and
1069 L<perlcall>.
1070
1071 =for apidoc AmU||G_ARRAY
1072 Used to indicate list context.  See C<L</GIMME_V>>, C<L</GIMME>> and
1073 L<perlcall>.
1074
1075 =for apidoc AmU||G_VOID
1076 Used to indicate void context.  See C<L</GIMME_V>> and L<perlcall>.
1077
1078 =for apidoc AmU||G_DISCARD
1079 Indicates that arguments returned from a callback should be discarded.  See
1080 L<perlcall>.
1081
1082 =for apidoc AmU||G_EVAL
1083
1084 Used to force a Perl C<eval> wrapper around a callback.  See
1085 L<perlcall>.
1086
1087 =for apidoc AmU||G_NOARGS
1088
1089 Indicates that no arguments are being sent to a callback.  See
1090 L<perlcall>.
1091
1092 =cut
1093 */
1094
1095 #define G_SCALAR        2
1096 #define G_ARRAY         3
1097 #define G_VOID          1
1098 #define G_WANT          3
1099
1100 /* extra flags for Perl_call_* routines */
1101 #define G_DISCARD       4       /* Call FREETMPS.
1102                                    Don't change this without consulting the
1103                                    hash actions codes defined in hv.h */
1104 #define G_EVAL          8       /* Assume eval {} around subroutine call. */
1105 #define G_NOARGS       16       /* Don't construct a @_ array. */
1106 #define G_KEEPERR      32       /* Warn for errors, don't overwrite $@ */
1107 #define G_NODEBUG      64       /* Disable debugging at toplevel.  */
1108 #define G_METHOD      128       /* Calling method. */
1109 #define G_FAKINGEVAL  256       /* Faking an eval context for call_sv or
1110                                    fold_constants. */
1111 #define G_UNDEF_FILL  512       /* Fill the stack with &PL_sv_undef
1112                                    A special case for UNSHIFT in
1113                                    Perl_magic_methcall().  */
1114 #define G_WRITING_TO_STDERR 1024 /* Perl_write_to_stderr() is calling
1115                                     Perl_magic_methcall().  */
1116 #define G_RE_REPARSING 0x800     /* compiling a run-time /(?{..})/ */
1117 #define G_METHOD_NAMED 4096     /* calling named method, eg without :: or ' */
1118
1119 /* flag bits for PL_in_eval */
1120 #define EVAL_NULL       0       /* not in an eval */
1121 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
1122 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
1123 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
1124 #define EVAL_INREQUIRE  8       /* The code is being required. */
1125 #define EVAL_RE_REPARSING 0x10  /* eval_sv() called with G_RE_REPARSING */
1126
1127 /* Support for switching (stack and block) contexts.
1128  * This ensures magic doesn't invalidate local stack and cx pointers.
1129  */
1130
1131 #define PERLSI_UNKNOWN          -1
1132 #define PERLSI_UNDEF            0
1133 #define PERLSI_MAIN             1
1134 #define PERLSI_MAGIC            2
1135 #define PERLSI_SORT             3
1136 #define PERLSI_SIGNAL           4
1137 #define PERLSI_OVERLOAD         5
1138 #define PERLSI_DESTROY          6
1139 #define PERLSI_WARNHOOK         7
1140 #define PERLSI_DIEHOOK          8
1141 #define PERLSI_REQUIRE          9
1142 #define PERLSI_MULTICALL       10
1143
1144 struct stackinfo {
1145     AV *                si_stack;       /* stack for current runlevel */
1146     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
1147     struct stackinfo *  si_prev;
1148     struct stackinfo *  si_next;
1149     I32                 si_cxix;        /* current context index */
1150     I32                 si_cxmax;       /* maximum allocated index */
1151     I32                 si_type;        /* type of runlevel */
1152     I32                 si_markoff;     /* offset where markstack begins for us.
1153                                          * currently used only with DEBUGGING,
1154                                          * but not #ifdef-ed for bincompat */
1155 };
1156
1157 typedef struct stackinfo PERL_SI;
1158
1159 #define cxstack         (PL_curstackinfo->si_cxstack)
1160 #define cxstack_ix      (PL_curstackinfo->si_cxix)
1161 #define cxstack_max     (PL_curstackinfo->si_cxmax)
1162
1163 #ifdef DEBUGGING
1164 #  define       SET_MARK_OFFSET \
1165     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
1166 #else
1167 #  define       SET_MARK_OFFSET NOOP
1168 #endif
1169
1170 #define PUSHSTACKi(type) \
1171     STMT_START {                                                        \
1172         PERL_SI *next = PL_curstackinfo->si_next;                       \
1173         DEBUG_l({                                                       \
1174             int i = 0; PERL_SI *p = PL_curstackinfo;                    \
1175             while (p) { i++; p = p->si_prev; }                          \
1176             Perl_deb(aTHX_ "push STACKINFO %d at %s:%d\n",              \
1177                          i, __FILE__, __LINE__);})                      \
1178         if (!next) {                                                    \
1179             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
1180             next->si_prev = PL_curstackinfo;                            \
1181             PL_curstackinfo->si_next = next;                            \
1182         }                                                               \
1183         next->si_type = type;                                           \
1184         next->si_cxix = -1;                                             \
1185         AvFILLp(next->si_stack) = 0;                                    \
1186         SWITCHSTACK(PL_curstack,next->si_stack);                        \
1187         PL_curstackinfo = next;                                         \
1188         SET_MARK_OFFSET;                                                \
1189     } STMT_END
1190
1191 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
1192
1193 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
1194  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
1195 #define POPSTACK \
1196     STMT_START {                                                        \
1197         dSP;                                                            \
1198         PERL_SI * const prev = PL_curstackinfo->si_prev;                \
1199         DEBUG_l({                                                       \
1200             int i = -1; PERL_SI *p = PL_curstackinfo;                   \
1201             while (p) { i++; p = p->si_prev; }                          \
1202             Perl_deb(aTHX_ "pop  STACKINFO %d at %s:%d\n",              \
1203                          i, __FILE__, __LINE__);})                      \
1204         if (!prev) {                                                    \
1205             Perl_croak_popstack();                                      \
1206         }                                                               \
1207         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
1208         /* don't free prev here, free them all at the END{} */          \
1209         PL_curstackinfo = prev;                                         \
1210     } STMT_END
1211
1212 #define POPSTACK_TO(s) \
1213     STMT_START {                                                        \
1214         while (PL_curstack != s) {                                      \
1215             dounwind(-1);                                               \
1216             POPSTACK;                                                   \
1217         }                                                               \
1218     } STMT_END
1219
1220 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
1221 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
1222
1223 /*
1224 =head1 Multicall Functions
1225
1226 =for apidoc Ams||dMULTICALL
1227 Declare local variables for a multicall.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1228
1229 =for apidoc Ams||PUSH_MULTICALL
1230 Opening bracket for a lightweight callback.
1231 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1232
1233 =for apidoc Ams||MULTICALL
1234 Make a lightweight callback.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1235
1236 =for apidoc Ams||POP_MULTICALL
1237 Closing bracket for a lightweight callback.
1238 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1239
1240 =cut
1241 */
1242
1243 #define dMULTICALL \
1244     SV **newsp;                 /* set by POPBLOCK */                   \
1245     PERL_CONTEXT *cx;                                                   \
1246     CV *multicall_cv;                                                   \
1247     OP *multicall_cop;                                                  \
1248     bool multicall_oldcatch;                                            \
1249     U8 hasargs = 0              /* used by PUSHSUB */
1250
1251 #define PUSH_MULTICALL(the_cv) \
1252     PUSH_MULTICALL_FLAGS(the_cv, 0)
1253
1254 /* Like PUSH_MULTICALL, but allows you to specify extra flags
1255  * for the CX stack entry (this isn't part of the public API) */
1256
1257 #define PUSH_MULTICALL_FLAGS(the_cv, flags) \
1258     STMT_START {                                                        \
1259         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1260         CV * const cv = _nOnclAshIngNamE_;                              \
1261         PADLIST * const padlist = CvPADLIST(cv);                        \
1262         multicall_oldcatch = CATCH_GET;                                 \
1263         CATCH_SET(TRUE);                                                \
1264         PUSHSTACKi(PERLSI_MULTICALL);                                   \
1265         PUSHBLOCK(cx, (CXt_SUB|CXp_MULTICALL|flags), PL_stack_sp);      \
1266         PUSHSUB(cx);                                                    \
1267         cx->blk_sub.old_savestack_ix = PL_savestack_ix;                  \
1268         SAVEVPTR(PL_op);                                                \
1269         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1270             CvDEPTH(cv)++;                                              \
1271         if (CvDEPTH(cv) >= 2) {                                         \
1272             PERL_STACK_OVERFLOW_CHECK();                                \
1273             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1274         }                                                               \
1275         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1276         multicall_cv = cv;                                              \
1277         multicall_cop = CvSTART(cv);                                    \
1278     } STMT_END
1279
1280 #define MULTICALL \
1281     STMT_START {                                                        \
1282         PL_op = multicall_cop;                                          \
1283         CALLRUNOPS(aTHX);                                               \
1284     } STMT_END
1285
1286 #define POP_MULTICALL \
1287     STMT_START {                                                        \
1288         cx = &cxstack[cxstack_ix];                                      \
1289         CvDEPTH(multicall_cv) = cx->blk_sub.olddepth;                   \
1290         LEAVESUB(multicall_cv);                                         \
1291         POPBLOCK(cx,PL_curpm);                                          \
1292         /* includes partial unrolled POPSUB(): */                       \
1293         LEAVE_SCOPE(cx->blk_sub.old_savestack_ix);                      \
1294         PL_comppad = cx->blk_sub.prevcomppad;                           \
1295         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
1296         POPSTACK;                                                       \
1297         CATCH_SET(multicall_oldcatch);                                  \
1298         SPAGAIN;                                                        \
1299     } STMT_END
1300
1301 /* Change the CV of an already-pushed MULTICALL CxSUB block.
1302  * (this isn't part of the public API) */
1303
1304 #define CHANGE_MULTICALL_FLAGS(the_cv, flags) \
1305     STMT_START {                                                        \
1306         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1307         CV * const cv = _nOnclAshIngNamE_;                              \
1308         PADLIST * const padlist = CvPADLIST(cv);                        \
1309         cx = &cxstack[cxstack_ix];                                      \
1310         assert(cx->cx_type & CXp_MULTICALL);                            \
1311         CvDEPTH(multicall_cv) = cx->blk_sub.olddepth;                   \
1312         LEAVESUB(multicall_cv);                                         \
1313         cx->cx_type = (CXt_SUB|CXp_MULTICALL|flags);                    \
1314         {                                                               \
1315             /* save a few things that we don't want PUSHSUB to zap */   \
1316             PAD * const prevcomppad = cx->blk_sub.prevcomppad;          \
1317             SSize_t old_floor = cx->blk_sub.old_tmpsfloor;              \
1318             SSize_t floor = PL_tmps_floor;                              \
1319             PUSHSUB(cx);                                                \
1320             /* undo the stuff that PUSHSUB zapped */                    \
1321             cx->blk_sub.prevcomppad = prevcomppad ;                     \
1322             cx->blk_sub.old_tmpsfloor = old_floor;                      \
1323             PL_tmps_floor = floor;                                      \
1324         }                                                               \
1325         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1326             CvDEPTH(cv)++;                                              \
1327         if (CvDEPTH(cv) >= 2) {                                         \
1328             PERL_STACK_OVERFLOW_CHECK();                                \
1329             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1330         }                                                               \
1331         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1332         multicall_cv = cv;                                              \
1333         multicall_cop = CvSTART(cv);                                    \
1334     } STMT_END
1335 /*
1336  * ex: set ts=8 sts=4 sw=4 et:
1337  */