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