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     union {
 765         struct { /* valid if type is LOOP_FOR or LOOP_PLAIN (but {NULL,0})*/
 766             AV * ary; /* use the stack if this is NULL */
 767             IV ix;
 768         } ary;
 769         struct { /* valid if type is LOOP_LAZYIV */
 770             IV cur;
 771             IV end;
 772         } lazyiv;
 773         struct { /* valid if type if LOOP_LAZYSV */
 774             SV * cur;
 775             SV * end; /* maxiumum value (or minimum in reverse) */
 776         } lazysv;
 777     } state_u;
 778 #ifdef USE_ITHREADS
 779     PAD *oldcomppad; /* needed to map itervar_u.svp during thread clone */
 780 #endif
 781 };
 782
 783 #define CxITERVAR(c)                                                    \
 784         (CxPADLOOP(c)                                                   \
 785             ? (c)->blk_loop.itervar_u.svp                               \
 786             : (c)->blk_loop.itervar_u.svp                               \
 787                 ? isGV((c)->blk_loop.itervar_u.gv)                      \
 788                     ? &GvSV((c)->blk_loop.itervar_u.gv)                 \
 789                     : (SV **)&(c)->blk_loop.itervar_u.gv                \
 790                 : (SV**)NULL)
 791
 792 #define CxLABEL(c)      (0 + CopLABEL((c)->blk_oldcop))
 793 #define CxLABEL_len(c,len)      (0 + CopLABEL_len((c)->blk_oldcop, len))
 794 #define CxLABEL_len_flags(c,len,flags)  (0 + CopLABEL_len_flags((c)->blk_oldcop, len, flags))
 795 #define CxHASARGS(c)    (((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
 796 #define CxLVAL(c)       (0 + ((c)->blk_u16 & 0xff))
 797 /* POPSUB has already been performed on this context frame */
 798 #define CxPOPSUB_DONE 0x100
 799
 800
 801 #define PUSHLOOP_PLAIN(cx, s)                                           \
 802         cx->blk_loop.resetsp = s - PL_stack_base;                       \
 803         cx->blk_loop.my_op = cLOOP;                                     \
 804         cx->blk_loop.state_u.ary.ary = NULL;                            \
 805         cx->blk_loop.state_u.ary.ix = 0;                                \
 806         cx->blk_loop.old_savestack_ix = PL_savestack_ix;                \
 807         cx->blk_loop.itervar_u.svp = 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, 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         PUSHLOOP_FOR_setpad(cx);
 823
 824 #define POPLOOP(cx)                                                     \
 825         LEAVE_SCOPE(cx->blk_loop.old_savestack_ix);                     \
 826         if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {                            \
 827             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.cur);           \
 828             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.end);           \
 829         }                                                               \
 830         if (CxTYPE(cx) == CXt_LOOP_FOR)                                 \
 831             SvREFCNT_dec(cx->blk_loop.state_u.ary.ary);
 832
 833 /* given/when context */
 834 struct block_givwhen {
 835         OP *leave_op;
 836 };
 837
 838 #define PUSHGIVEN(cx)                                                   \
 839         cx->blk_givwhen.leave_op = cLOGOP->op_other;
 840
 841 #define PUSHWHEN PUSHGIVEN
 842
 843 /* context common to subroutines, evals and loops */
 844 struct block {
 845     U8          blku_type;      /* what kind of context this is */
 846     U8          blku_gimme;     /* is this block running in list context? */
 847     U16         blku_u16;       /* used by block_sub and block_eval (so far) */
 848     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
 849     COP *       blku_oldcop;    /* old curcop pointer */
 850     I32         blku_oldmarksp; /* mark stack index */
 851     I32         blku_oldscopesp;        /* scope stack index */
 852     PMOP *      blku_oldpm;     /* values of pattern match vars */
 853
 854     union {
 855         struct block_sub        blku_sub;
 856         struct block_format     blku_format;
 857         struct block_eval       blku_eval;
 858         struct block_loop       blku_loop;
 859         struct block_givwhen    blku_givwhen;
 860     } blk_u;
 861 };
 862 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
 863 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
 864 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
 865 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
 866 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
 867 #define blk_gimme       cx_u.cx_blk.blku_gimme
 868 #define blk_u16         cx_u.cx_blk.blku_u16
 869 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
 870 #define blk_format      cx_u.cx_blk.blk_u.blku_format
 871 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
 872 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
 873 #define blk_givwhen     cx_u.cx_blk.blk_u.blku_givwhen
 874
 875 #define DEBUG_CX(action)                                                \
 876     DEBUG_l(                                                            \
 877         Perl_deb(aTHX_ "CX %ld %s %s (scope %ld,%ld) at %s:%d\n",       \
 878                     (long)cxstack_ix,                                   \
 879                     action,                                             \
 880                     PL_block_type[CxTYPE(&cxstack[cxstack_ix])],        \
 881                     (long)PL_scopestack_ix,                             \
 882                     (long)(cxstack[cxstack_ix].blk_oldscopesp),         \
 883                     __FILE__, __LINE__));
 884
 885 /* Enter a block. */
 886 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
 887         cx->cx_type             = t,                                    \
 888         cx->blk_oldsp           = sp - PL_stack_base,                   \
 889         cx->blk_oldcop          = PL_curcop,                            \
 890         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
 891         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
 892         cx->blk_oldpm           = PL_curpm,                             \
 893         cx->blk_gimme           = (U8)gimme;                            \
 894         DEBUG_CX("PUSH");
 895
 896 /* Exit a block (RETURN and LAST). */
 897 #define POPBLOCK(cx,pm)                                                 \
 898         DEBUG_CX("POP");                                                \
 899         cx = &cxstack[cxstack_ix--],                                    \
 900         newsp            = PL_stack_base + cx->blk_oldsp,               \
 901         PL_curcop        = cx->blk_oldcop,                              \
 902         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 903         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 904         pm               = cx->blk_oldpm,                               \
 905         gimme            = cx->blk_gimme;
 906
 907 /* Continue a block elsewhere (NEXT and REDO). */
 908 #define TOPBLOCK(cx)                                                    \
 909         DEBUG_CX("TOP");                                                \
 910         cx  = &cxstack[cxstack_ix],                                     \
 911         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
 912         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 913         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 914         PL_curpm         = cx->blk_oldpm;
 915
 916 /* substitution context */
 917 struct subst {
 918     U8          sbu_type;       /* what kind of context this is */
 919     U8          sbu_rflags;
 920     U16         sbu_rxtainted;  /* matches struct block */
 921     I32         sbu_oldsave;
 922     SSize_t     sbu_iters;
 923     SSize_t     sbu_maxiters;
 924     char *      sbu_orig;
 925     SV *        sbu_dstr;
 926     SV *        sbu_targ;
 927     char *      sbu_s;
 928     char *      sbu_m;
 929     char *      sbu_strend;
 930     void *      sbu_rxres;
 931     REGEXP *    sbu_rx;
 932 };
 933 #define sb_iters        cx_u.cx_subst.sbu_iters
 934 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
 935 #define sb_rflags       cx_u.cx_subst.sbu_rflags
 936 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
 937 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
 938 #define sb_orig         cx_u.cx_subst.sbu_orig
 939 #define sb_dstr         cx_u.cx_subst.sbu_dstr
 940 #define sb_targ         cx_u.cx_subst.sbu_targ
 941 #define sb_s            cx_u.cx_subst.sbu_s
 942 #define sb_m            cx_u.cx_subst.sbu_m
 943 #define sb_strend       cx_u.cx_subst.sbu_strend
 944 #define sb_rxres        cx_u.cx_subst.sbu_rxres
 945 #define sb_rx           cx_u.cx_subst.sbu_rx
 946
 947 #ifdef PERL_CORE
 948 #  define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],               \
 949         cx->sb_iters            = iters,                                \
 950         cx->sb_maxiters         = maxiters,                             \
 951         cx->sb_rflags           = r_flags,                              \
 952         cx->sb_oldsave          = oldsave,                              \
 953         cx->sb_rxtainted        = rxtainted,                            \
 954         cx->sb_orig             = orig,                                 \
 955         cx->sb_dstr             = dstr,                                 \
 956         cx->sb_targ             = targ,                                 \
 957         cx->sb_s                = s,                                    \
 958         cx->sb_m                = m,                                    \
 959         cx->sb_strend           = strend,                               \
 960         cx->sb_rxres            = NULL,                                 \
 961         cx->sb_rx               = rx,                                   \
 962         cx->cx_type             = CXt_SUBST | (once ? CXp_ONCE : 0);    \
 963         rxres_save(&cx->sb_rxres, rx);                                  \
 964         (void)ReREFCNT_inc(rx);                                         \
 965         SvREFCNT_inc_void_NN(targ)
 966
 967 #  define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                     \
 968         rxres_free(&cx->sb_rxres);                                      \
 969         ReREFCNT_dec(cx->sb_rx);                                        \
 970         SvREFCNT_dec_NN(cx->sb_targ)
 971 #endif
 972
 973 #define CxONCE(cx)              ((cx)->cx_type & CXp_ONCE)
 974
 975 struct context {
 976     union {
 977         struct block    cx_blk;
 978         struct subst    cx_subst;
 979     } cx_u;
 980 };
 981 #define cx_type cx_u.cx_subst.sbu_type
 982
 983 /* If you re-order these, there is also an array of uppercase names in perl.h
 984    and a static array of context names in pp_ctl.c  */
 985 #define CXTYPEMASK      0xf
 986 #define CXt_NULL        0
 987 #define CXt_WHEN        1
 988 #define CXt_BLOCK       2
 989 /* When micro-optimising :-) keep GIVEN next to the LOOPs, as these 5 share a
 990    jump table in pp_ctl.c
 991    The first 4 don't have a 'case' in at least one switch statement in pp_ctl.c
 992 */
 993 #define CXt_GIVEN       3
 994 /* This is first so that CXt_LOOP_FOR|CXt_LOOP_LAZYIV is CXt_LOOP_LAZYIV */
 995 #define CXt_LOOP_FOR    4
 996 #define CXt_LOOP_PLAIN  5
 997 #define CXt_LOOP_LAZYSV 6
 998 #define CXt_LOOP_LAZYIV 7
 999 #define CXt_SUB         8
1000 #define CXt_FORMAT      9
1001 #define CXt_EVAL       10
1002 #define CXt_SUBST      11
1003 /* SUBST doesn't feature in all switch statements.  */
1004
1005 /* private flags for CXt_SUB and CXt_NULL
1006    However, this is checked in many places which do not check the type, so
1007    this bit needs to be kept clear for most everything else. For reasons I
1008    haven't investigated, it can coexist with CXp_FOR_DEF */
1009 #define CXp_MULTICALL   0x10    /* part of a multicall (so don't
1010                                    tear down context on exit). */
1011
1012 /* private flags for CXt_SUB and CXt_FORMAT */
1013 #define CXp_HASARGS     0x20
1014 #define CXp_SUB_RE      0x40    /* code called within regex, i.e. (?{}) */
1015 #define CXp_SUB_RE_FAKE 0x80    /* fake sub CX for (?{}) in current scope */
1016
1017 /* private flags for CXt_EVAL */
1018 #define CXp_REAL        0x20    /* truly eval'', not a lookalike */
1019 #define CXp_TRYBLOCK    0x40    /* eval{}, not eval'' or similar */
1020
1021 /* private flags for CXt_LOOP */
1022 #define CXp_FOR_DEF     0x10    /* foreach using $_ */
1023 #define CXp_FOR_LVREF   0x20    /* foreach using \$var */
1024 #define CxPADLOOP(c)    ((c)->blk_loop.my_op->op_targ)
1025
1026 /* private flags for CXt_SUBST */
1027 #define CXp_ONCE        0x10    /* What was sbu_once in struct subst */
1028
1029 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
1030 #define CxTYPE_is_LOOP(c)       (((c)->cx_type & 0xC) == 0x4)
1031 #define CxMULTICALL(c)  (((c)->cx_type & CXp_MULTICALL)                 \
1032                          == CXp_MULTICALL)
1033 #define CxREALEVAL(c)   (((c)->cx_type & (CXTYPEMASK|CXp_REAL))         \
1034                          == (CXt_EVAL|CXp_REAL))
1035 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXTYPEMASK|CXp_TRYBLOCK))     \
1036                          == (CXt_EVAL|CXp_TRYBLOCK))
1037 #define CxFOREACH(c)    (CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN)
1038 #define CxFOREACHDEF(c) ((CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN) \
1039                          && ((c)->cx_type & CXp_FOR_DEF))
1040
1041 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
1042
1043 /*
1044 =head1 "Gimme" Values
1045 */
1046
1047 /*
1048 =for apidoc AmU||G_SCALAR
1049 Used to indicate scalar context.  See C<L</GIMME_V>>, C<L</GIMME>>, and
1050 L<perlcall>.
1051
1052 =for apidoc AmU||G_ARRAY
1053 Used to indicate list context.  See C<L</GIMME_V>>, C<L</GIMME>> and
1054 L<perlcall>.
1055
1056 =for apidoc AmU||G_VOID
1057 Used to indicate void context.  See C<L</GIMME_V>> and L<perlcall>.
1058
1059 =for apidoc AmU||G_DISCARD
1060 Indicates that arguments returned from a callback should be discarded.  See
1061 L<perlcall>.
1062
1063 =for apidoc AmU||G_EVAL
1064
1065 Used to force a Perl C<eval> wrapper around a callback.  See
1066 L<perlcall>.
1067
1068 =for apidoc AmU||G_NOARGS
1069
1070 Indicates that no arguments are being sent to a callback.  See
1071 L<perlcall>.
1072
1073 =cut
1074 */
1075
1076 #define G_SCALAR        2
1077 #define G_ARRAY         3
1078 #define G_VOID          1
1079 #define G_WANT          3
1080
1081 /* extra flags for Perl_call_* routines */
1082 #define G_DISCARD       4       /* Call FREETMPS.
1083                                    Don't change this without consulting the
1084                                    hash actions codes defined in hv.h */
1085 #define G_EVAL          8       /* Assume eval {} around subroutine call. */
1086 #define G_NOARGS       16       /* Don't construct a @_ array. */
1087 #define G_KEEPERR      32       /* Warn for errors, don't overwrite $@ */
1088 #define G_NODEBUG      64       /* Disable debugging at toplevel.  */
1089 #define G_METHOD      128       /* Calling method. */
1090 #define G_FAKINGEVAL  256       /* Faking an eval context for call_sv or
1091                                    fold_constants. */
1092 #define G_UNDEF_FILL  512       /* Fill the stack with &PL_sv_undef
1093                                    A special case for UNSHIFT in
1094                                    Perl_magic_methcall().  */
1095 #define G_WRITING_TO_STDERR 1024 /* Perl_write_to_stderr() is calling
1096                                     Perl_magic_methcall().  */
1097 #define G_RE_REPARSING 0x800     /* compiling a run-time /(?{..})/ */
1098 #define G_METHOD_NAMED 4096     /* calling named method, eg without :: or ' */
1099
1100 /* flag bits for PL_in_eval */
1101 #define EVAL_NULL       0       /* not in an eval */
1102 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
1103 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
1104 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
1105 #define EVAL_INREQUIRE  8       /* The code is being required. */
1106 #define EVAL_RE_REPARSING 0x10  /* eval_sv() called with G_RE_REPARSING */
1107
1108 /* Support for switching (stack and block) contexts.
1109  * This ensures magic doesn't invalidate local stack and cx pointers.
1110  */
1111
1112 #define PERLSI_UNKNOWN          -1
1113 #define PERLSI_UNDEF            0
1114 #define PERLSI_MAIN             1
1115 #define PERLSI_MAGIC            2
1116 #define PERLSI_SORT             3
1117 #define PERLSI_SIGNAL           4
1118 #define PERLSI_OVERLOAD         5
1119 #define PERLSI_DESTROY          6
1120 #define PERLSI_WARNHOOK         7
1121 #define PERLSI_DIEHOOK          8
1122 #define PERLSI_REQUIRE          9
1123 #define PERLSI_MULTICALL       10
1124
1125 struct stackinfo {
1126     AV *                si_stack;       /* stack for current runlevel */
1127     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
1128     struct stackinfo *  si_prev;
1129     struct stackinfo *  si_next;
1130     I32                 si_cxix;        /* current context index */
1131     I32                 si_cxmax;       /* maximum allocated index */
1132     I32                 si_type;        /* type of runlevel */
1133     I32                 si_markoff;     /* offset where markstack begins for us.
1134                                          * currently used only with DEBUGGING,
1135                                          * but not #ifdef-ed for bincompat */
1136 };
1137
1138 typedef struct stackinfo PERL_SI;
1139
1140 #define cxstack         (PL_curstackinfo->si_cxstack)
1141 #define cxstack_ix      (PL_curstackinfo->si_cxix)
1142 #define cxstack_max     (PL_curstackinfo->si_cxmax)
1143
1144 #ifdef DEBUGGING
1145 #  define       SET_MARK_OFFSET \
1146     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
1147 #else
1148 #  define       SET_MARK_OFFSET NOOP
1149 #endif
1150
1151 #define PUSHSTACKi(type) \
1152     STMT_START {                                                        \
1153         PERL_SI *next = PL_curstackinfo->si_next;                       \
1154         DEBUG_l({                                                       \
1155             int i = 0; PERL_SI *p = PL_curstackinfo;                    \
1156             while (p) { i++; p = p->si_prev; }                          \
1157             Perl_deb(aTHX_ "push STACKINFO %d at %s:%d\n",              \
1158                          i, __FILE__, __LINE__);})                      \
1159         if (!next) {                                                    \
1160             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
1161             next->si_prev = PL_curstackinfo;                            \
1162             PL_curstackinfo->si_next = next;                            \
1163         }                                                               \
1164         next->si_type = type;                                           \
1165         next->si_cxix = -1;                                             \
1166         AvFILLp(next->si_stack) = 0;                                    \
1167         SWITCHSTACK(PL_curstack,next->si_stack);                        \
1168         PL_curstackinfo = next;                                         \
1169         SET_MARK_OFFSET;                                                \
1170     } STMT_END
1171
1172 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
1173
1174 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
1175  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
1176 #define POPSTACK \
1177     STMT_START {                                                        \
1178         dSP;                                                            \
1179         PERL_SI * const prev = PL_curstackinfo->si_prev;                \
1180         DEBUG_l({                                                       \
1181             int i = -1; PERL_SI *p = PL_curstackinfo;                   \
1182             while (p) { i++; p = p->si_prev; }                          \
1183             Perl_deb(aTHX_ "pop  STACKINFO %d at %s:%d\n",              \
1184                          i, __FILE__, __LINE__);})                      \
1185         if (!prev) {                                                    \
1186             Perl_croak_popstack();                                      \
1187         }                                                               \
1188         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
1189         /* don't free prev here, free them all at the END{} */          \
1190         PL_curstackinfo = prev;                                         \
1191     } STMT_END
1192
1193 #define POPSTACK_TO(s) \
1194     STMT_START {                                                        \
1195         while (PL_curstack != s) {                                      \
1196             dounwind(-1);                                               \
1197             POPSTACK;                                                   \
1198         }                                                               \
1199     } STMT_END
1200
1201 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
1202 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
1203
1204 /*
1205 =head1 Multicall Functions
1206
1207 =for apidoc Ams||dMULTICALL
1208 Declare local variables for a multicall.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1209
1210 =for apidoc Ams||PUSH_MULTICALL
1211 Opening bracket for a lightweight callback.
1212 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1213
1214 =for apidoc Ams||MULTICALL
1215 Make a lightweight callback.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1216
1217 =for apidoc Ams||POP_MULTICALL
1218 Closing bracket for a lightweight callback.
1219 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1220
1221 =cut
1222 */
1223
1224 #define dMULTICALL \
1225     SV **newsp;                 /* set by POPBLOCK */                   \
1226     PERL_CONTEXT *cx;                                                   \
1227     CV *multicall_cv;                                                   \
1228     OP *multicall_cop;                                                  \
1229     bool multicall_oldcatch;                                            \
1230     U8 hasargs = 0              /* used by PUSHSUB */
1231
1232 #define PUSH_MULTICALL(the_cv) \
1233     PUSH_MULTICALL_FLAGS(the_cv, 0)
1234
1235 /* Like PUSH_MULTICALL, but allows you to specify extra flags
1236  * for the CX stack entry (this isn't part of the public API) */
1237
1238 #define PUSH_MULTICALL_FLAGS(the_cv, flags) \
1239     STMT_START {                                                        \
1240         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1241         CV * const cv = _nOnclAshIngNamE_;                              \
1242         PADLIST * const padlist = CvPADLIST(cv);                        \
1243         multicall_oldcatch = CATCH_GET;                                 \
1244         CATCH_SET(TRUE);                                                \
1245         PUSHSTACKi(PERLSI_MULTICALL);                                   \
1246         PUSHBLOCK(cx, (CXt_SUB|CXp_MULTICALL|flags), PL_stack_sp);      \
1247         PUSHSUB(cx);                                                    \
1248         cx->blk_sub.old_savestack_ix = PL_savestack_ix;                  \
1249         SAVEVPTR(PL_op);                                                \
1250         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1251             CvDEPTH(cv)++;                                              \
1252         if (CvDEPTH(cv) >= 2) {                                         \
1253             PERL_STACK_OVERFLOW_CHECK();                                \
1254             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1255         }                                                               \
1256         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1257         multicall_cv = cv;                                              \
1258         multicall_cop = CvSTART(cv);                                    \
1259     } STMT_END
1260
1261 #define MULTICALL \
1262     STMT_START {                                                        \
1263         PL_op = multicall_cop;                                          \
1264         CALLRUNOPS(aTHX);                                               \
1265     } STMT_END
1266
1267 #define POP_MULTICALL \
1268     STMT_START {                                                        \
1269         cx = &cxstack[cxstack_ix];                                      \
1270         CvDEPTH(multicall_cv) = cx->blk_sub.olddepth;                   \
1271         LEAVESUB(multicall_cv);                                         \
1272         POPBLOCK(cx,PL_curpm);                                          \
1273         /* includes partial unrolled POPSUB(): */                       \
1274         LEAVE_SCOPE(cx->blk_sub.old_savestack_ix);                      \
1275         PL_comppad = cx->blk_sub.prevcomppad;                           \
1276         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
1277         POPSTACK;                                                       \
1278         CATCH_SET(multicall_oldcatch);                                  \
1279         SPAGAIN;                                                        \
1280     } STMT_END
1281
1282 /* Change the CV of an already-pushed MULTICALL CxSUB block.
1283  * (this isn't part of the public API) */
1284
1285 #define CHANGE_MULTICALL_FLAGS(the_cv, flags) \
1286     STMT_START {                                                        \
1287         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1288         CV * const cv = _nOnclAshIngNamE_;                              \
1289         PADLIST * const padlist = CvPADLIST(cv);                        \
1290         cx = &cxstack[cxstack_ix];                                      \
1291         assert(cx->cx_type & CXp_MULTICALL);                            \
1292         CvDEPTH(multicall_cv) = cx->blk_sub.olddepth;                   \
1293         LEAVESUB(multicall_cv);                                         \
1294         cx->cx_type = (CXt_SUB|CXp_MULTICALL|flags);                    \
1295         {                                                               \
1296             /* save a few things that we don't want PUSHSUB to zap */   \
1297             PAD * const prevcomppad = cx->blk_sub.prevcomppad;          \
1298             SSize_t old_floor = cx->blk_sub.old_tmpsfloor;              \
1299             SSize_t floor = PL_tmps_floor;                              \
1300             PUSHSUB(cx);                                                \
1301             /* undo the stuff that PUSHSUB zapped */                    \
1302             cx->blk_sub.prevcomppad = prevcomppad ;                     \
1303             cx->blk_sub.old_tmpsfloor = old_floor;                      \
1304             PL_tmps_floor = floor;                                      \
1305         }                                                               \
1306         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1307             CvDEPTH(cv)++;                                              \
1308         if (CvDEPTH(cv) >= 2) {                                         \
1309             PERL_STACK_OVERFLOW_CHECK();                                \
1310             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1311         }                                                               \
1312         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1313         multicall_cv = cv;                                              \
1314         multicall_cop = CvSTART(cv);                                    \
1315     } STMT_END
1316 /*
1317  * ex: set ts=8 sts=4 sw=4 et:
1318  */