regcomp.c

   1 /*    regcomp.c
   2  */
   3
   4 /*
   5  * "A fair jaw-cracker dwarf-language must be."  --Samwise Gamgee
   6  */
   7
   8 /* NOTE: this is derived from Henry Spencer's regexp code, and should not
   9  * confused with the original package (see point 3 below).  Thanks, Henry!
  10  */
  11
  12 /* Additional note: this code is very heavily munged from Henry's version
  13  * in places.  In some spots I've traded clarity for efficiency, so don't
  14  * blame Henry for some of the lack of readability.
  15  */
  16
  17 /* The names of the functions have been changed from regcomp and
  18  * regexec to  pregcomp and pregexec in order to avoid conflicts
  19  * with the POSIX routines of the same names.
  20 */
  21
  22 #ifdef PERL_EXT_RE_BUILD
  23 /* need to replace pregcomp et al, so enable that */
  24 #  ifndef PERL_IN_XSUB_RE
  25 #    define PERL_IN_XSUB_RE
  26 #  endif
  27 /* need access to debugger hooks */
  28 #  if defined(PERL_EXT_RE_DEBUG) && !defined(DEBUGGING)
  29 #    define DEBUGGING
  30 #  endif
  31 #endif
  32
  33 #ifdef PERL_IN_XSUB_RE
  34 /* We *really* need to overwrite these symbols: */
  35 #  define Perl_pregcomp my_regcomp
  36 #  define Perl_regdump my_regdump
  37 #  define Perl_regprop my_regprop
  38 #  define Perl_pregfree my_regfree
  39 #  define Perl_re_intuit_string my_re_intuit_string
  40 /* *These* symbols are masked to allow static link. */
  41 #  define Perl_regnext my_regnext
  42 #  define Perl_save_re_context my_save_re_context
  43 #  define Perl_reginitcolors my_reginitcolors
  44
  45 #  define PERL_NO_GET_CONTEXT
  46 #endif
  47
  48 /*SUPPRESS 112*/
  49 /*
  50  * pregcomp and pregexec -- regsub and regerror are not used in perl
  51  *
  52  *      Copyright (c) 1986 by University of Toronto.
  53  *      Written by Henry Spencer.  Not derived from licensed software.
  54  *
  55  *      Permission is granted to anyone to use this software for any
  56  *      purpose on any computer system, and to redistribute it freely,
  57  *      subject to the following restrictions:
  58  *
  59  *      1. The author is not responsible for the consequences of use of
  60  *              this software, no matter how awful, even if they arise
  61  *              from defects in it.
  62  *
  63  *      2. The origin of this software must not be misrepresented, either
  64  *              by explicit claim or by omission.
  65  *
  66  *      3. Altered versions must be plainly marked as such, and must not
  67  *              be misrepresented as being the original software.
  68  *
  69  *
  70  ****    Alterations to Henry's code are...
  71  ****
  72  ****    Copyright (c) 1991-2001, Larry Wall
  73  ****
  74  ****    You may distribute under the terms of either the GNU General Public
  75  ****    License or the Artistic License, as specified in the README file.
  76
  77  *
  78  * Beware that some of this code is subtly aware of the way operator
  79  * precedence is structured in regular expressions.  Serious changes in
  80  * regular-expression syntax might require a total rethink.
  81  */
  82 #include "EXTERN.h"
  83 #define PERL_IN_REGCOMP_C
  84 #include "perl.h"
  85
  86 #ifdef PERL_IN_XSUB_RE
  87 #  if defined(PERL_CAPI) || defined(PERL_OBJECT)
  88 #    include "XSUB.h"
  89 #  endif
  90 #else
  91 #  include "INTERN.h"
  92 #endif
  93
  94 #define REG_COMP_C
  95 #include "regcomp.h"
  96
  97 #ifdef op
  98 #undef op
  99 #endif /* op */
 100
 101 #ifdef MSDOS
 102 # if defined(BUGGY_MSC6)
 103  /* MSC 6.00A breaks on op/regexp.t test 85 unless we turn this off */
 104  # pragma optimize("a",off)
 105  /* But MSC 6.00A is happy with 'w', for aliases only across function calls*/
 106  # pragma optimize("w",on )
 107 # endif /* BUGGY_MSC6 */
 108 #endif /* MSDOS */
 109
 110 #ifndef STATIC
 111 #define STATIC  static
 112 #endif
 113
 114 typedef struct RExC_state_t {
 115     U16         flags16;                /* are we folding, multilining? */
 116     char        *precomp;               /* uncompiled string. */
 117     regexp      *rx;
 118     char        *start;                 /* Start of input for compile */
 119     char        *end;                   /* End of input for compile */
 120     char        *parse;                 /* Input-scan pointer. */
 121     I32         whilem_seen;            /* number of WHILEM in this expr */
 122     regnode     *emit_start;            /* Start of emitted-code area */
 123     regnode     *emit;                  /* Code-emit pointer; &regdummy = don't = compiling */
 124     I32         naughty;                /* How bad is this pattern? */
 125     I32         sawback;                /* Did we see \1, ...? */
 126     U32         seen;
 127     I32         size;                   /* Code size. */
 128     I32         npar;                   /* () count. */
 129     I32         extralen;
 130     I32         seen_zerolen;
 131     I32         seen_evals;
 132     I32         utf8;
 133 #if ADD_TO_REGEXEC
 134     char        *starttry;              /* -Dr: where regtry was called. */
 135 #define RExC_starttry   (pRExC_state->starttry)
 136 #endif
 137 } RExC_state_t;
 138
 139 #define RExC_flags16    (pRExC_state->flags16)
 140 #define RExC_precomp    (pRExC_state->precomp)
 141 #define RExC_rx         (pRExC_state->rx)
 142 #define RExC_start      (pRExC_state->start)
 143 #define RExC_end        (pRExC_state->end)
 144 #define RExC_parse      (pRExC_state->parse)
 145 #define RExC_whilem_seen        (pRExC_state->whilem_seen)
 146 #define RExC_offsets    (pRExC_state->rx->offsets) /* I am not like the others */
 147 #define RExC_emit       (pRExC_state->emit)
 148 #define RExC_emit_start (pRExC_state->emit_start)
 149 #define RExC_naughty    (pRExC_state->naughty)
 150 #define RExC_sawback    (pRExC_state->sawback)
 151 #define RExC_seen       (pRExC_state->seen)
 152 #define RExC_size       (pRExC_state->size)
 153 #define RExC_npar       (pRExC_state->npar)
 154 #define RExC_extralen   (pRExC_state->extralen)
 155 #define RExC_seen_zerolen       (pRExC_state->seen_zerolen)
 156 #define RExC_seen_evals (pRExC_state->seen_evals)
 157 #define RExC_utf8       (pRExC_state->utf8)
 158
 159 #define ISMULT1(c)      ((c) == '*' || (c) == '+' || (c) == '?')
 160 #define ISMULT2(s)      ((*s) == '*' || (*s) == '+' || (*s) == '?' || \
 161         ((*s) == '{' && regcurly(s)))
 162
 163 #ifdef SPSTART
 164 #undef SPSTART          /* dratted cpp namespace... */
 165 #endif
 166 /*
 167  * Flags to be passed up and down.
 168  */
 169 #define WORST           0       /* Worst case. */
 170 #define HASWIDTH        0x1     /* Known to match non-null strings. */
 171 #define SIMPLE          0x2     /* Simple enough to be STAR/PLUS operand. */
 172 #define SPSTART         0x4     /* Starts with * or +. */
 173 #define TRYAGAIN        0x8     /* Weeded out a declaration. */
 174
 175 /* Length of a variant. */
 176
 177 typedef struct scan_data_t {
 178     I32 len_min;
 179     I32 len_delta;
 180     I32 pos_min;
 181     I32 pos_delta;
 182     SV *last_found;
 183     I32 last_end;                       /* min value, <0 unless valid. */
 184     I32 last_start_min;
 185     I32 last_start_max;
 186     SV **longest;                       /* Either &l_fixed, or &l_float. */
 187     SV *longest_fixed;
 188     I32 offset_fixed;
 189     SV *longest_float;
 190     I32 offset_float_min;
 191     I32 offset_float_max;
 192     I32 flags;
 193     I32 whilem_c;
 194     I32 *last_closep;
 195     struct regnode_charclass_class *start_class;
 196 } scan_data_t;
 197
 198 /*
 199  * Forward declarations for pregcomp()'s friends.
 200  */
 201
 202 static scan_data_t zero_scan_data = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
 203                                       0, 0, 0, 0, 0, 0};
 204
 205 #define SF_BEFORE_EOL           (SF_BEFORE_SEOL|SF_BEFORE_MEOL)
 206 #define SF_BEFORE_SEOL          0x1
 207 #define SF_BEFORE_MEOL          0x2
 208 #define SF_FIX_BEFORE_EOL       (SF_FIX_BEFORE_SEOL|SF_FIX_BEFORE_MEOL)
 209 #define SF_FL_BEFORE_EOL        (SF_FL_BEFORE_SEOL|SF_FL_BEFORE_MEOL)
 210
 211 #ifdef NO_UNARY_PLUS
 212 #  define SF_FIX_SHIFT_EOL      (0+2)
 213 #  define SF_FL_SHIFT_EOL               (0+4)
 214 #else
 215 #  define SF_FIX_SHIFT_EOL      (+2)
 216 #  define SF_FL_SHIFT_EOL               (+4)
 217 #endif
 218
 219 #define SF_FIX_BEFORE_SEOL      (SF_BEFORE_SEOL << SF_FIX_SHIFT_EOL)
 220 #define SF_FIX_BEFORE_MEOL      (SF_BEFORE_MEOL << SF_FIX_SHIFT_EOL)
 221
 222 #define SF_FL_BEFORE_SEOL       (SF_BEFORE_SEOL << SF_FL_SHIFT_EOL)
 223 #define SF_FL_BEFORE_MEOL       (SF_BEFORE_MEOL << SF_FL_SHIFT_EOL) /* 0x20 */
 224 #define SF_IS_INF               0x40
 225 #define SF_HAS_PAR              0x80
 226 #define SF_IN_PAR               0x100
 227 #define SF_HAS_EVAL             0x200
 228 #define SCF_DO_SUBSTR           0x400
 229 #define SCF_DO_STCLASS_AND      0x0800
 230 #define SCF_DO_STCLASS_OR       0x1000
 231 #define SCF_DO_STCLASS          (SCF_DO_STCLASS_AND|SCF_DO_STCLASS_OR)
 232 #define SCF_WHILEM_VISITED_POS  0x2000
 233
 234 #define UTF RExC_utf8
 235 #define LOC (RExC_flags16 & PMf_LOCALE)
 236 #define FOLD (RExC_flags16 & PMf_FOLD)
 237
 238 #define OOB_UNICODE             12345678
 239 #define OOB_NAMEDCLASS          -1
 240
 241 #define CHR_SVLEN(sv) (UTF ? sv_len_utf8(sv) : SvCUR(sv))
 242 #define CHR_DIST(a,b) (UTF ? utf8_distance(a,b) : a - b)
 243
 244
 245 /* length of regex to show in messages that don't mark a position within */
 246 #define RegexLengthToShowInErrorMessages 127
 247
 248 /*
 249  * If MARKER[12] are adjusted, be sure to adjust the constants at the top
 250  * of t/op/regmesg.t, the tests in t/op/re_tests, and those in
 251  * op/pragma/warn/regcomp.
 252  */
 253 #define MARKER1 "<-- HERE"    /* marker as it appears in the description */
 254 #define MARKER2 " <-- HERE "  /* marker as it appears within the regex */
 255
 256 #define REPORT_LOCATION " in regex; marked by " MARKER1 " in m/%.*s" MARKER2 "%s/"
 257
 258 /*
 259  * Calls SAVEDESTRUCTOR_X if needed, then calls Perl_croak with the given
 260  * arg. Show regex, up to a maximum length. If it's too long, chop and add
 261  * "...".
 262  */
 263 #define FAIL(msg)                                                             \
 264     STMT_START {                                                             \
 265         char *ellipses = "";                                                 \
 266         unsigned len = strlen(RExC_precomp);                                \
 267                                                                              \
 268         if (!SIZE_ONLY)                                                      \
 269             SAVEDESTRUCTOR_X(clear_re,(void*)RExC_rx);                 \
 270                                                                              \
 271         if (len > RegexLengthToShowInErrorMessages) {                        \
 272             /* chop 10 shorter than the max, to ensure meaning of "..." */   \
 273             len = RegexLengthToShowInErrorMessages - 10;                     \
 274             ellipses = "...";                                                \
 275         }                                                                    \
 276         Perl_croak(aTHX_ "%s in regex m/%.*s%s/",                            \
 277                    msg, (int)len, RExC_precomp, ellipses);                  \
 278     } STMT_END
 279
 280 /*
 281  * Calls SAVEDESTRUCTOR_X if needed, then calls Perl_croak with the given
 282  * args. Show regex, up to a maximum length. If it's too long, chop and add
 283  * "...".
 284  */
 285 #define FAIL2(pat,msg)                                                        \
 286     STMT_START {                                                             \
 287         char *ellipses = "";                                                 \
 288         unsigned len = strlen(RExC_precomp);                                \
 289                                                                              \
 290         if (!SIZE_ONLY)                                                      \
 291             SAVEDESTRUCTOR_X(clear_re,(void*)RExC_rx);                 \
 292                                                                              \
 293         if (len > RegexLengthToShowInErrorMessages) {                        \
 294             /* chop 10 shorter than the max, to ensure meaning of "..." */   \
 295             len = RegexLengthToShowInErrorMessages - 10;                     \
 296             ellipses = "...";                                                \
 297         }                                                                    \
 298         S_re_croak2(aTHX_ pat, " in regex m/%.*s%s/",                        \
 299                     msg, (int)len, RExC_precomp, ellipses);                \
 300     } STMT_END
 301
 302
 303 /*
 304  * Simple_vFAIL -- like FAIL, but marks the current location in the scan
 305  */
 306 #define Simple_vFAIL(m)                                                      \
 307     STMT_START {                                                             \
 308       unsigned offset = strlen(RExC_precomp)-(RExC_end-RExC_parse); \
 309                                                                              \
 310       Perl_croak(aTHX_ "%s" REPORT_LOCATION,               \
 311                  m, (int)offset, RExC_precomp, RExC_precomp + offset);     \
 312     } STMT_END
 313
 314 /*
 315  * Calls SAVEDESTRUCTOR_X if needed, then Simple_vFAIL()
 316  */
 317 #define vFAIL(m)                                                             \
 318     STMT_START {                                                             \
 319       if (!SIZE_ONLY)                                                        \
 320             SAVEDESTRUCTOR_X(clear_re,(void*)RExC_rx);                 \
 321       Simple_vFAIL(m);                                                       \
 322     } STMT_END
 323
 324 /*
 325  * Like Simple_vFAIL(), but accepts two arguments.
 326  */
 327 #define Simple_vFAIL2(m,a1)                                                  \
 328     STMT_START {                                                             \
 329       unsigned offset = strlen(RExC_precomp)-(RExC_end-RExC_parse); \
 330                                                                              \
 331       S_re_croak2(aTHX_ m, REPORT_LOCATION, a1,       \
 332                   (int)offset, RExC_precomp, RExC_precomp + offset);       \
 333     } STMT_END
 334
 335 /*
 336  * Calls SAVEDESTRUCTOR_X if needed, then Simple_vFAIL2().
 337  */
 338 #define vFAIL2(m,a1)                                                         \
 339     STMT_START {                                                             \
 340       if (!SIZE_ONLY)                                                        \
 341             SAVEDESTRUCTOR_X(clear_re,(void*)RExC_rx);                 \
 342       Simple_vFAIL2(m, a1);                                                  \
 343     } STMT_END
 344
 345
 346 /*
 347  * Like Simple_vFAIL(), but accepts three arguments.
 348  */
 349 #define Simple_vFAIL3(m, a1, a2)                                             \
 350     STMT_START {                                                             \
 351       unsigned offset = strlen(RExC_precomp)-(RExC_end-RExC_parse); \
 352                                                                              \
 353       S_re_croak2(aTHX_ m, REPORT_LOCATION, a1, a2,   \
 354                   (int)offset, RExC_precomp, RExC_precomp + offset);       \
 355     } STMT_END
 356
 357 /*
 358  * Calls SAVEDESTRUCTOR_X if needed, then Simple_vFAIL3().
 359  */
 360 #define vFAIL3(m,a1,a2)                                                      \
 361     STMT_START {                                                             \
 362       if (!SIZE_ONLY)                                                        \
 363             SAVEDESTRUCTOR_X(clear_re,(void*)RExC_rx);                 \
 364       Simple_vFAIL3(m, a1, a2);                                              \
 365     } STMT_END
 366
 367 /*
 368  * Like Simple_vFAIL(), but accepts four arguments.
 369  */
 370 #define Simple_vFAIL4(m, a1, a2, a3)                                         \
 371     STMT_START {                                                             \
 372       unsigned offset = strlen(RExC_precomp)-(RExC_end-RExC_parse); \
 373                                                                              \
 374       S_re_croak2(aTHX_ m, REPORT_LOCATION, a1, a2, a3,\
 375                   (int)offset, RExC_precomp, RExC_precomp + offset);       \
 376     } STMT_END
 377
 378 /*
 379  * Like Simple_vFAIL(), but accepts five arguments.
 380  */
 381 #define Simple_vFAIL5(m, a1, a2, a3, a4)                                     \
 382     STMT_START {                                                             \
 383       unsigned offset = strlen(RExC_precomp)-(RExC_end-RExC_parse); \
 384       S_re_croak2(aTHX_ m, REPORT_LOCATION, a1, a2, a3, a4,\
 385                   (int)offset, RExC_precomp, RExC_precomp + offset);       \
 386     } STMT_END
 387
 388
 389 #define vWARN(loc,m)                                                         \
 390     STMT_START {                                                             \
 391         unsigned offset = strlen(RExC_precomp)-(RExC_end-(loc));          \
 392         Perl_warner(aTHX_ WARN_REGEXP, "%s" REPORT_LOCATION,\
 393                  m, (int)offset, RExC_precomp, RExC_precomp + offset);          \
 394     } STMT_END                                                               \
 395
 396 #define vWARNdep(loc,m)                                                         \
 397     STMT_START {                                                             \
 398         unsigned offset = strlen(RExC_precomp)-(RExC_end-(loc));          \
 399         int warn_cat = ckWARN(WARN_REGEXP) ? WARN_REGEXP : WARN_DEPRECATED;  \
 400         Perl_warner(aTHX_ warn_cat, "%s" REPORT_LOCATION,\
 401                  m, (int)offset, RExC_precomp, RExC_precomp + offset);          \
 402     } STMT_END                                                               \
 403
 404
 405 #define vWARN2(loc, m, a1)                                                   \
 406     STMT_START {                                                             \
 407         unsigned offset = strlen(RExC_precomp)-(RExC_end-(loc));          \
 408         Perl_warner(aTHX_ WARN_REGEXP, m REPORT_LOCATION,\
 409                  a1,                                                         \
 410                  (int)offset, RExC_precomp, RExC_precomp + offset);        \
 411     } STMT_END
 412
 413 #define vWARN3(loc, m, a1, a2)                                               \
 414     STMT_START {                                                             \
 415       unsigned offset = strlen(RExC_precomp) - (RExC_end - (loc));        \
 416         Perl_warner(aTHX_ WARN_REGEXP, m REPORT_LOCATION,                    \
 417                  a1, a2,                                                     \
 418                  (int)offset, RExC_precomp, RExC_precomp + offset);        \
 419     } STMT_END
 420
 421 #define vWARN4(loc, m, a1, a2, a3)                                           \
 422     STMT_START {                                                             \
 423       unsigned offset = strlen(RExC_precomp)-(RExC_end-(loc));            \
 424         Perl_warner(aTHX_ WARN_REGEXP, m REPORT_LOCATION,\
 425                  a1, a2, a3,                                                 \
 426                  (int)offset, RExC_precomp, RExC_precomp + offset);        \
 427     } STMT_END
 428
 429 /* used for the parse_flags section for (?c) -- japhy */
 430 #define vWARN5(loc, m, a1, a2, a3, a4)                                       \
 431   STMT_START {                                                   \
 432       unsigned offset = strlen(RExC_precomp)-(RExC_end-(loc));   \
 433         Perl_warner(aTHX_ WARN_REGEXP, m REPORT_LOCATION,      \
 434                  a1, a2, a3, a4,                                 \
 435                  (int)offset, RExC_precomp, RExC_precomp + offset);  \
 436     } STMT_END
 437
 438
 439 /* Allow for side effects in s */
 440 #define REGC(c,s) STMT_START { if (!SIZE_ONLY) *(s) = (c); else (void)(s);} STMT_END
 441
 442 /* Macros for recording node offsets.   20001227 mjd@plover.com
 443  * Nodes are numbered 1, 2, 3, 4.  Node #n's position is recorded in
 444  * element 2*n-1 of the array.  Element #2n holds the byte length node #n.
 445  * Element 0 holds the number n.
 446  */
 447
 448 #define MJD_OFFSET_DEBUG(x)
 449 /* #define MJD_OFFSET_DEBUG(x) fprintf x */
 450
 451
 452 #  define Set_Node_Offset_To_R(node,byte)                           \
 453    STMT_START {                                        \
 454      if (! SIZE_ONLY) {                                  \
 455        if((node) < 0) {                   \
 456          Perl_croak(aTHX_ "value of node is %d in Offset macro", node); \
 457        } else {                                                        \
 458          RExC_offsets[2*(node)-1] = (byte);                               \
 459        }                                                               \
 460      }                                                                 \
 461    } STMT_END
 462
 463 #  define Set_Node_Offset(node,byte) Set_Node_Offset_To_R((node)-RExC_emit_start, (byte)-RExC_start)
 464 #  define Set_Cur_Node_Offset Set_Node_Offset(RExC_emit, RExC_parse)
 465
 466 #  define Set_Node_Length_To_R(node,len)                            \
 467    STMT_START {                                        \
 468      if (! SIZE_ONLY) {                                  \
 469        MJD_OFFSET_DEBUG((stderr, "** (%d) size of node %d is %d.\n", __LINE__, (node), (len))); \
 470        if((node) < 0) {                   \
 471          Perl_croak(aTHX_ "value of node is %d in Length macro", node); \
 472        } else {                                                        \
 473          RExC_offsets[2*(node)] = (len);                               \
 474        }                                                               \
 475      }                                                                 \
 476    } STMT_END
 477
 478 #  define Set_Node_Length(node,len) Set_Node_Length_To_R((node)-RExC_emit_start, len)
 479 #  define Set_Cur_Node_Length(len)  Set_Node_Length(RExC_emit, len)
 480 #  define Set_Node_Cur_Length(node)   Set_Node_Length(node, RExC_parse - parse_start)
 481
 482 /* Get offsets and lengths */
 483 #define Node_Offset(n) (RExC_offsets[2*((n)-RExC_emit_start)-1])
 484 #define Node_Length(n) (RExC_offsets[2*((n)-RExC_emit_start)])
 485
 486 static void clear_re(pTHXo_ void *r);
 487
 488 /* Mark that we cannot extend a found fixed substring at this point.
 489    Updata the longest found anchored substring and the longest found
 490    floating substrings if needed. */
 491
 492 STATIC void
 493 S_scan_commit(pTHX_ RExC_state_t *pRExC_state, scan_data_t *data)
 494 {
 495     STRLEN l = CHR_SVLEN(data->last_found);
 496     STRLEN old_l = CHR_SVLEN(*data->longest);
 497
 498     if ((l >= old_l) && ((l > old_l) || (data->flags & SF_BEFORE_EOL))) {
 499         sv_setsv(*data->longest, data->last_found);
 500         if (*data->longest == data->longest_fixed) {
 501             data->offset_fixed = l ? data->last_start_min : data->pos_min;
 502             if (data->flags & SF_BEFORE_EOL)
 503                 data->flags
 504                     |= ((data->flags & SF_BEFORE_EOL) << SF_FIX_SHIFT_EOL);
 505             else
 506                 data->flags &= ~SF_FIX_BEFORE_EOL;
 507         }
 508         else {
 509             data->offset_float_min = l ? data->last_start_min : data->pos_min;
 510             data->offset_float_max = (l
 511                                       ? data->last_start_max
 512                                       : data->pos_min + data->pos_delta);
 513             if (data->flags & SF_BEFORE_EOL)
 514                 data->flags
 515                     |= ((data->flags & SF_BEFORE_EOL) << SF_FL_SHIFT_EOL);
 516             else
 517                 data->flags &= ~SF_FL_BEFORE_EOL;
 518         }
 519     }
 520     SvCUR_set(data->last_found, 0);
 521     data->last_end = -1;
 522     data->flags &= ~SF_BEFORE_EOL;
 523 }
 524
 525 /* Can match anything (initialization) */
 526 STATIC void
 527 S_cl_anything(pTHX_ RExC_state_t *pRExC_state, struct regnode_charclass_class *cl)
 528 {
 529     int value;
 530
 531     ANYOF_CLASS_ZERO(cl);
 532     for (value = 0; value < 256; ++value)
 533         ANYOF_BITMAP_SET(cl, value);
 534     cl->flags = ANYOF_EOS|ANYOF_UNICODE_ALL;
 535     if (LOC)
 536         cl->flags |= ANYOF_LOCALE;
 537 }
 538
 539 /* Can match anything (initialization) */
 540 STATIC int
 541 S_cl_is_anything(pTHX_ struct regnode_charclass_class *cl)
 542 {
 543     int value;
 544
 545     for (value = 0; value <= ANYOF_MAX; value += 2)
 546         if (ANYOF_CLASS_TEST(cl, value) && ANYOF_CLASS_TEST(cl, value + 1))
 547             return 1;
 548     if (!(cl->flags & ANYOF_UNICODE_ALL))
 549         return 0;
 550     for (value = 0; value < 256; ++value)
 551         if (!ANYOF_BITMAP_TEST(cl, value))
 552             return 0;
 553     return 1;
 554 }
 555
 556 /* Can match anything (initialization) */
 557 STATIC void
 558 S_cl_init(pTHX_ RExC_state_t *pRExC_state, struct regnode_charclass_class *cl)
 559 {
 560     Zero(cl, 1, struct regnode_charclass_class);
 561     cl->type = ANYOF;
 562     cl_anything(pRExC_state, cl);
 563 }
 564
 565 STATIC void
 566 S_cl_init_zero(pTHX_ RExC_state_t *pRExC_state, struct regnode_charclass_class *cl)
 567 {
 568     Zero(cl, 1, struct regnode_charclass_class);
 569     cl->type = ANYOF;
 570     cl_anything(pRExC_state, cl);
 571     if (LOC)
 572         cl->flags |= ANYOF_LOCALE;
 573 }
 574
 575 /* 'And' a given class with another one.  Can create false positives */
 576 /* We assume that cl is not inverted */
 577 STATIC void
 578 S_cl_and(pTHX_ struct regnode_charclass_class *cl,
 579          struct regnode_charclass_class *and_with)
 580 {
 581     if (!(and_with->flags & ANYOF_CLASS)
 582         && !(cl->flags & ANYOF_CLASS)
 583         && (and_with->flags & ANYOF_LOCALE) == (cl->flags & ANYOF_LOCALE)
 584         && !(and_with->flags & ANYOF_FOLD)
 585         && !(cl->flags & ANYOF_FOLD)) {
 586         int i;
 587
 588         if (and_with->flags & ANYOF_INVERT)
 589             for (i = 0; i < ANYOF_BITMAP_SIZE; i++)
 590                 cl->bitmap[i] &= ~and_with->bitmap[i];
 591         else
 592             for (i = 0; i < ANYOF_BITMAP_SIZE; i++)
 593                 cl->bitmap[i] &= and_with->bitmap[i];
 594     } /* XXXX: logic is complicated otherwise, leave it along for a moment. */
 595     if (!(and_with->flags & ANYOF_EOS))
 596         cl->flags &= ~ANYOF_EOS;
 597
 598     if (cl->flags & ANYOF_UNICODE_ALL && and_with->flags & ANYOF_UNICODE) {
 599         cl->flags &= ~ANYOF_UNICODE_ALL;
 600         cl->flags |= ANYOF_UNICODE;
 601         ARG_SET(cl, ARG(and_with));
 602     }
 603     if (!(and_with->flags & ANYOF_UNICODE_ALL))
 604         cl->flags &= ~ANYOF_UNICODE_ALL;
 605     if (!(and_with->flags & (ANYOF_UNICODE|ANYOF_UNICODE_ALL)))
 606         cl->flags &= ~ANYOF_UNICODE;
 607 }
 608
 609 /* 'OR' a given class with another one.  Can create false positives */
 610 /* We assume that cl is not inverted */
 611 STATIC void
 612 S_cl_or(pTHX_ RExC_state_t *pRExC_state, struct regnode_charclass_class *cl, struct regnode_charclass_class *or_with)
 613 {
 614     if (or_with->flags & ANYOF_INVERT) {
 615         /* We do not use
 616          * (B1 | CL1) | (!B2 & !CL2) = (B1 | !B2 & !CL2) | (CL1 | (!B2 & !CL2))
 617          *   <= (B1 | !B2) | (CL1 | !CL2)
 618          * which is wasteful if CL2 is small, but we ignore CL2:
 619          *   (B1 | CL1) | (!B2 & !CL2) <= (B1 | CL1) | !B2 = (B1 | !B2) | CL1
 620          * XXXX Can we handle case-fold?  Unclear:
 621          *   (OK1(i) | OK1(i')) | !(OK1(i) | OK1(i')) =
 622          *   (OK1(i) | OK1(i')) | (!OK1(i) & !OK1(i'))
 623          */
 624         if ( (or_with->flags & ANYOF_LOCALE) == (cl->flags & ANYOF_LOCALE)
 625              && !(or_with->flags & ANYOF_FOLD)
 626              && !(cl->flags & ANYOF_FOLD) ) {
 627             int i;
 628
 629             for (i = 0; i < ANYOF_BITMAP_SIZE; i++)
 630                 cl->bitmap[i] |= ~or_with->bitmap[i];
 631         } /* XXXX: logic is complicated otherwise */
 632         else {
 633             cl_anything(pRExC_state, cl);
 634         }
 635     } else {
 636         /* (B1 | CL1) | (B2 | CL2) = (B1 | B2) | (CL1 | CL2)) */
 637         if ( (or_with->flags & ANYOF_LOCALE) == (cl->flags & ANYOF_LOCALE)
 638              && (!(or_with->flags & ANYOF_FOLD)
 639                  || (cl->flags & ANYOF_FOLD)) ) {
 640             int i;
 641
 642             /* OR char bitmap and class bitmap separately */
 643             for (i = 0; i < ANYOF_BITMAP_SIZE; i++)
 644                 cl->bitmap[i] |= or_with->bitmap[i];
 645             if (or_with->flags & ANYOF_CLASS) {
 646                 for (i = 0; i < ANYOF_CLASSBITMAP_SIZE; i++)
 647                     cl->classflags[i] |= or_with->classflags[i];
 648                 cl->flags |= ANYOF_CLASS;
 649             }
 650         }
 651         else { /* XXXX: logic is complicated, leave it along for a moment. */
 652             cl_anything(pRExC_state, cl);
 653         }
 654     }
 655     if (or_with->flags & ANYOF_EOS)
 656         cl->flags |= ANYOF_EOS;
 657
 658     if (cl->flags & ANYOF_UNICODE && or_with->flags & ANYOF_UNICODE &&
 659         ARG(cl) != ARG(or_with)) {
 660         cl->flags |= ANYOF_UNICODE_ALL;
 661         cl->flags &= ~ANYOF_UNICODE;
 662     }
 663     if (or_with->flags & ANYOF_UNICODE_ALL) {
 664         cl->flags |= ANYOF_UNICODE_ALL;
 665         cl->flags &= ~ANYOF_UNICODE;
 666     }
 667 }
 668
 669 /* REx optimizer.  Converts nodes into quickier variants "in place".
 670    Finds fixed substrings.  */
 671
 672 /* Stops at toplevel WHILEM as well as at `last'. At end *scanp is set
 673    to the position after last scanned or to NULL. */
 674
 675 STATIC I32
 676 S_study_chunk(pTHX_ RExC_state_t *pRExC_state, regnode **scanp, I32 *deltap, regnode *last, scan_data_t *data, U32 flags)
 677                         /* scanp: Start here (read-write). */
 678                         /* deltap: Write maxlen-minlen here. */
 679                         /* last: Stop before this one. */
 680 {
 681     I32 min = 0, pars = 0, code;
 682     regnode *scan = *scanp, *next;
 683     I32 delta = 0;
 684     int is_inf = (flags & SCF_DO_SUBSTR) && (data->flags & SF_IS_INF);
 685     int is_inf_internal = 0;            /* The studied chunk is infinite */
 686     I32 is_par = OP(scan) == OPEN ? ARG(scan) : 0;
 687     scan_data_t data_fake;
 688     struct regnode_charclass_class and_with; /* Valid if flags & SCF_DO_STCLASS_OR */
 689
 690     while (scan && OP(scan) != END && scan < last) {
 691         /* Peephole optimizer: */
 692
 693         if (PL_regkind[(U8)OP(scan)] == EXACT) {
 694             /* Merge several consecutive EXACTish nodes into one. */
 695             regnode *n = regnext(scan);
 696             U32 stringok = 1;
 697 #ifdef DEBUGGING
 698             regnode *stop = scan;
 699 #endif
 700
 701             next = scan + NODE_SZ_STR(scan);
 702             /* Skip NOTHING, merge EXACT*. */
 703             while (n &&
 704                    ( PL_regkind[(U8)OP(n)] == NOTHING ||
 705                      (stringok && (OP(n) == OP(scan))))
 706                    && NEXT_OFF(n)
 707                    && NEXT_OFF(scan) + NEXT_OFF(n) < I16_MAX) {
 708                 if (OP(n) == TAIL || n > next)
 709                     stringok = 0;
 710                 if (PL_regkind[(U8)OP(n)] == NOTHING) {
 711                     NEXT_OFF(scan) += NEXT_OFF(n);
 712                     next = n + NODE_STEP_REGNODE;
 713 #ifdef DEBUGGING
 714                     if (stringok)
 715                         stop = n;
 716 #endif
 717                     n = regnext(n);
 718                 }
 719                 else if (stringok) {
 720                     int oldl = STR_LEN(scan);
 721                     regnode *nnext = regnext(n);
 722
 723                     if (oldl + STR_LEN(n) > U8_MAX)
 724                         break;
 725                     NEXT_OFF(scan) += NEXT_OFF(n);
 726                     STR_LEN(scan) += STR_LEN(n);
 727                     next = n + NODE_SZ_STR(n);
 728                     /* Now we can overwrite *n : */
 729                     Move(STRING(n), STRING(scan) + oldl, STR_LEN(n), char);
 730 #ifdef DEBUGGING
 731                     stop = next - 1;
 732 #endif
 733                     n = nnext;
 734                 }
 735             }
 736 #ifdef DEBUGGING
 737             /* Allow dumping */
 738             n = scan + NODE_SZ_STR(scan);
 739             while (n <= stop) {
 740                 if (PL_regkind[(U8)OP(n)] != NOTHING || OP(n) == NOTHING) {
 741                     OP(n) = OPTIMIZED;
 742                     NEXT_OFF(n) = 0;
 743                 }
 744                 n++;
 745             }
 746 #endif
 747         }
 748         /* Follow the next-chain of the current node and optimize
 749            away all the NOTHINGs from it.  */
 750         if (OP(scan) != CURLYX) {
 751             int max = (reg_off_by_arg[OP(scan)]
 752                        ? I32_MAX
 753                        /* I32 may be smaller than U16 on CRAYs! */
 754                        : (I32_MAX < U16_MAX ? I32_MAX : U16_MAX));
 755             int off = (reg_off_by_arg[OP(scan)] ? ARG(scan) : NEXT_OFF(scan));
 756             int noff;
 757             regnode *n = scan;
 758
 759             /* Skip NOTHING and LONGJMP. */
 760             while ((n = regnext(n))
 761                    && ((PL_regkind[(U8)OP(n)] == NOTHING && (noff = NEXT_OFF(n)))
 762                        || ((OP(n) == LONGJMP) && (noff = ARG(n))))
 763                    && off + noff < max)
 764                 off += noff;
 765             if (reg_off_by_arg[OP(scan)])
 766                 ARG(scan) = off;
 767             else
 768                 NEXT_OFF(scan) = off;
 769         }
 770         /* The principal pseudo-switch.  Cannot be a switch, since we
 771            look into several different things.  */
 772         if (OP(scan) == BRANCH || OP(scan) == BRANCHJ
 773                    || OP(scan) == IFTHEN || OP(scan) == SUSPEND) {
 774             next = regnext(scan);
 775             code = OP(scan);
 776
 777             if (OP(next) == code || code == IFTHEN || code == SUSPEND) {
 778                 I32 max1 = 0, min1 = I32_MAX, num = 0;
 779                 struct regnode_charclass_class accum;
 780
 781                 if (flags & SCF_DO_SUBSTR) /* XXXX Add !SUSPEND? */
 782                     scan_commit(pRExC_state, data); /* Cannot merge strings after this. */
 783                 if (flags & SCF_DO_STCLASS)
 784                     cl_init_zero(pRExC_state, &accum);
 785                 while (OP(scan) == code) {
 786                     I32 deltanext, minnext, f = 0, fake;
 787                     struct regnode_charclass_class this_class;
 788
 789                     num++;
 790                     data_fake.flags = 0;
 791                     if (data) {
 792                         data_fake.whilem_c = data->whilem_c;
 793                         data_fake.last_closep = data->last_closep;
 794                     }
 795                     else
 796                         data_fake.last_closep = &fake;
 797                     next = regnext(scan);
 798                     scan = NEXTOPER(scan);
 799                     if (code != BRANCH)
 800                         scan = NEXTOPER(scan);
 801                     if (flags & SCF_DO_STCLASS) {
 802                         cl_init(pRExC_state, &this_class);
 803                         data_fake.start_class = &this_class;
 804                         f = SCF_DO_STCLASS_AND;
 805                     }
 806                     if (flags & SCF_WHILEM_VISITED_POS)
 807                         f |= SCF_WHILEM_VISITED_POS;
 808                     /* we suppose the run is continuous, last=next...*/
 809                     minnext = study_chunk(pRExC_state, &scan, &deltanext,
 810                                           next, &data_fake, f);
 811                     if (min1 > minnext)
 812                         min1 = minnext;
 813                     if (max1 < minnext + deltanext)
 814                         max1 = minnext + deltanext;
 815                     if (deltanext == I32_MAX)
 816                         is_inf = is_inf_internal = 1;
 817                     scan = next;
 818                     if (data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
 819                         pars++;
 820                     if (data && (data_fake.flags & SF_HAS_EVAL))
 821                         data->flags |= SF_HAS_EVAL;
 822                     if (data)
 823                         data->whilem_c = data_fake.whilem_c;
 824                     if (flags & SCF_DO_STCLASS)
 825                         cl_or(pRExC_state, &accum, &this_class);
 826                     if (code == SUSPEND)
 827                         break;
 828                 }
 829                 if (code == IFTHEN && num < 2) /* Empty ELSE branch */
 830                     min1 = 0;
 831                 if (flags & SCF_DO_SUBSTR) {
 832                     data->pos_min += min1;
 833                     data->pos_delta += max1 - min1;
 834                     if (max1 != min1 || is_inf)
 835                         data->longest = &(data->longest_float);
 836                 }
 837                 min += min1;
 838                 delta += max1 - min1;
 839                 if (flags & SCF_DO_STCLASS_OR) {
 840                     cl_or(pRExC_state, data->start_class, &accum);
 841                     if (min1) {
 842                         cl_and(data->start_class, &and_with);
 843                         flags &= ~SCF_DO_STCLASS;
 844                     }
 845                 }
 846                 else if (flags & SCF_DO_STCLASS_AND) {
 847                     if (min1) {
 848                         cl_and(data->start_class, &accum);
 849                         flags &= ~SCF_DO_STCLASS;
 850                     }
 851                     else {
 852                         /* Switch to OR mode: cache the old value of
 853                          * data->start_class */
 854                         StructCopy(data->start_class, &and_with,
 855                                    struct regnode_charclass_class);
 856                         flags &= ~SCF_DO_STCLASS_AND;
 857                         StructCopy(&accum, data->start_class,
 858                                    struct regnode_charclass_class);
 859                         flags |= SCF_DO_STCLASS_OR;
 860                         data->start_class->flags |= ANYOF_EOS;
 861                     }
 862                 }
 863             }
 864             else if (code == BRANCHJ)   /* single branch is optimized. */
 865                 scan = NEXTOPER(NEXTOPER(scan));
 866             else                        /* single branch is optimized. */
 867                 scan = NEXTOPER(scan);
 868             continue;
 869         }
 870         else if (OP(scan) == EXACT) {
 871             I32 l = STR_LEN(scan);
 872             UV uc = *((U8*)STRING(scan));
 873             if (UTF) {
 874                 U8 *s = (U8*)STRING(scan);
 875                 l = utf8_length(s, s + l);
 876                 uc = utf8_to_uvchr(s, NULL);
 877             }
 878             min += l;
 879             if (flags & SCF_DO_SUBSTR) { /* Update longest substr. */
 880                 /* The code below prefers earlier match for fixed
 881                    offset, later match for variable offset.  */
 882                 if (data->last_end == -1) { /* Update the start info. */
 883                     data->last_start_min = data->pos_min;
 884                     data->last_start_max = is_inf
 885                         ? I32_MAX : data->pos_min + data->pos_delta;
 886                 }
 887                 sv_catpvn(data->last_found, STRING(scan), STR_LEN(scan));
 888                 data->last_end = data->pos_min + l;
 889                 data->pos_min += l; /* As in the first entry. */
 890                 data->flags &= ~SF_BEFORE_EOL;
 891             }
 892             if (flags & SCF_DO_STCLASS_AND) {
 893                 /* Check whether it is compatible with what we know already! */
 894                 int compat = 1;
 895
 896                 if (uc >= 0x100 ||
 897                     (!(data->start_class->flags & (ANYOF_CLASS | ANYOF_LOCALE))
 898                     && !ANYOF_BITMAP_TEST(data->start_class, uc)
 899                     && (!(data->start_class->flags & ANYOF_FOLD)
 900                         || !ANYOF_BITMAP_TEST(data->start_class, PL_fold[uc])))
 901                     )
 902                     compat = 0;
 903                 ANYOF_CLASS_ZERO(data->start_class);
 904                 ANYOF_BITMAP_ZERO(data->start_class);
 905                 if (compat)
 906                     ANYOF_BITMAP_SET(data->start_class, uc);
 907                 data->start_class->flags &= ~ANYOF_EOS;
 908                 if (uc < 0x100)
 909                   data->start_class->flags &= ~ANYOF_UNICODE_ALL;
 910             }
 911             else if (flags & SCF_DO_STCLASS_OR) {
 912                 /* false positive possible if the class is case-folded */
 913                 if (uc < 0x100)
 914                     ANYOF_BITMAP_SET(data->start_class, uc);
 915                 else
 916                     data->start_class->flags |= ANYOF_UNICODE_ALL;
 917                 data->start_class->flags &= ~ANYOF_EOS;
 918                 cl_and(data->start_class, &and_with);
 919             }
 920             flags &= ~SCF_DO_STCLASS;
 921         }
 922         else if (PL_regkind[(U8)OP(scan)] == EXACT) { /* But OP != EXACT! */
 923             I32 l = STR_LEN(scan);
 924             UV uc = *((U8*)STRING(scan));
 925
 926             /* Search for fixed substrings supports EXACT only. */
 927             if (flags & SCF_DO_SUBSTR)
 928                 scan_commit(pRExC_state, data);
 929             if (UTF) {
 930                 U8 *s = (U8 *)STRING(scan);
 931                 l = utf8_length(s, s + l);
 932                 uc = utf8_to_uvchr(s, NULL);
 933             }
 934             min += l;
 935             if (data && (flags & SCF_DO_SUBSTR))
 936                 data->pos_min += l;
 937             if (flags & SCF_DO_STCLASS_AND) {
 938                 /* Check whether it is compatible with what we know already! */
 939                 int compat = 1;
 940
 941                 if (uc >= 0x100 ||
 942                     (!(data->start_class->flags & (ANYOF_CLASS | ANYOF_LOCALE))
 943                     && !ANYOF_BITMAP_TEST(data->start_class, uc)
 944                      && !ANYOF_BITMAP_TEST(data->start_class, PL_fold[uc])))
 945                     compat = 0;
 946                 ANYOF_CLASS_ZERO(data->start_class);
 947                 ANYOF_BITMAP_ZERO(data->start_class);
 948                 if (compat) {
 949                     ANYOF_BITMAP_SET(data->start_class, uc);
 950                     data->start_class->flags &= ~ANYOF_EOS;
 951                     data->start_class->flags |= ANYOF_FOLD;
 952                     if (OP(scan) == EXACTFL)
 953                         data->start_class->flags |= ANYOF_LOCALE;
 954                 }
 955             }
 956             else if (flags & SCF_DO_STCLASS_OR) {
 957                 if (data->start_class->flags & ANYOF_FOLD) {
 958                     /* false positive possible if the class is case-folded.
 959                        Assume that the locale settings are the same... */
 960                     if (uc < 0x100)
 961                         ANYOF_BITMAP_SET(data->start_class, uc);
 962                     data->start_class->flags &= ~ANYOF_EOS;
 963                 }
 964                 cl_and(data->start_class, &and_with);
 965             }
 966             flags &= ~SCF_DO_STCLASS;
 967         }
 968         else if (strchr((char*)PL_varies,OP(scan))) {
 969             I32 mincount, maxcount, minnext, deltanext, fl = 0;
 970             I32 f = flags, pos_before = 0;
 971             regnode *oscan = scan;
 972             struct regnode_charclass_class this_class;
 973             struct regnode_charclass_class *oclass = NULL;
 974
 975             switch (PL_regkind[(U8)OP(scan)]) {
 976             case WHILEM:                /* End of (?:...)* . */
 977                 scan = NEXTOPER(scan);
 978                 goto finish;
 979             case PLUS:
 980                 if (flags & (SCF_DO_SUBSTR | SCF_DO_STCLASS)) {
 981                     next = NEXTOPER(scan);
 982                     if (OP(next) == EXACT || (flags & SCF_DO_STCLASS)) {
 983                         mincount = 1;
 984                         maxcount = REG_INFTY;
 985                         next = regnext(scan);
 986                         scan = NEXTOPER(scan);
 987                         goto do_curly;
 988                     }
 989                 }
 990                 if (flags & SCF_DO_SUBSTR)
 991                     data->pos_min++;
 992                 min++;
 993                 /* Fall through. */
 994             case STAR:
 995                 if (flags & SCF_DO_STCLASS) {
 996                     mincount = 0;
 997                     maxcount = REG_INFTY;
 998                     next = regnext(scan);
 999                     scan = NEXTOPER(scan);
1000                     goto do_curly;
1001                 }
1002                 is_inf = is_inf_internal = 1;
1003                 scan = regnext(scan);
1004                 if (flags & SCF_DO_SUBSTR) {
1005                     scan_commit(pRExC_state, data); /* Cannot extend fixed substrings */
1006                     data->longest = &(data->longest_float);
1007                 }
1008                 goto optimize_curly_tail;
1009             case CURLY:
1010                 mincount = ARG1(scan);
1011                 maxcount = ARG2(scan);
1012                 next = regnext(scan);
1013                 if (OP(scan) == CURLYX) {
1014                     I32 lp = (data ? *(data->last_closep) : 0);
1015
1016                     scan->flags = ((lp <= U8_MAX) ? lp : U8_MAX);
1017                 }
1018                 scan = NEXTOPER(scan) + EXTRA_STEP_2ARGS;
1019               do_curly:
1020                 if (flags & SCF_DO_SUBSTR) {
1021                     if (mincount == 0) scan_commit(pRExC_state,data); /* Cannot extend fixed substrings */
1022                     pos_before = data->pos_min;
1023                 }
1024                 if (data) {
1025                     fl = data->flags;
1026                     data->flags &= ~(SF_HAS_PAR|SF_IN_PAR|SF_HAS_EVAL);
1027                     if (is_inf)
1028                         data->flags |= SF_IS_INF;
1029                 }
1030                 if (flags & SCF_DO_STCLASS) {
1031                     cl_init(pRExC_state, &this_class);
1032                     oclass = data->start_class;
1033                     data->start_class = &this_class;
1034                     f |= SCF_DO_STCLASS_AND;
1035                     f &= ~SCF_DO_STCLASS_OR;
1036                 }
1037                 /* These are the cases when once a subexpression
1038                    fails at a particular position, it cannot succeed
1039                    even after backtracking at the enclosing scope.
1040
1041                    XXXX what if minimal match and we are at the
1042                         initial run of {n,m}? */
1043                 if ((mincount != maxcount - 1) && (maxcount != REG_INFTY))
1044                     f &= ~SCF_WHILEM_VISITED_POS;
1045
1046                 /* This will finish on WHILEM, setting scan, or on NULL: */
1047                 minnext = study_chunk(pRExC_state, &scan, &deltanext, last, data,
1048                                       mincount == 0
1049                                         ? (f & ~SCF_DO_SUBSTR) : f);
1050
1051                 if (flags & SCF_DO_STCLASS)
1052                     data->start_class = oclass;
1053                 if (mincount == 0 || minnext == 0) {
1054                     if (flags & SCF_DO_STCLASS_OR) {
1055                         cl_or(pRExC_state, data->start_class, &this_class);
1056                     }
1057                     else if (flags & SCF_DO_STCLASS_AND) {
1058                         /* Switch to OR mode: cache the old value of
1059                          * data->start_class */
1060                         StructCopy(data->start_class, &and_with,
1061                                    struct regnode_charclass_class);
1062                         flags &= ~SCF_DO_STCLASS_AND;
1063                         StructCopy(&this_class, data->start_class,
1064                                    struct regnode_charclass_class);
1065                         flags |= SCF_DO_STCLASS_OR;
1066                         data->start_class->flags |= ANYOF_EOS;
1067                     }
1068                 } else {                /* Non-zero len */
1069                     if (flags & SCF_DO_STCLASS_OR) {
1070                         cl_or(pRExC_state, data->start_class, &this_class);
1071                         cl_and(data->start_class, &and_with);
1072                     }
1073                     else if (flags & SCF_DO_STCLASS_AND)
1074                         cl_and(data->start_class, &this_class);
1075                     flags &= ~SCF_DO_STCLASS;
1076                 }
1077                 if (!scan)              /* It was not CURLYX, but CURLY. */
1078                     scan = next;
1079                 if (ckWARN(WARN_REGEXP) && (minnext + deltanext == 0)
1080                     && data && !(data->flags & (SF_HAS_PAR|SF_IN_PAR))
1081                     && maxcount <= REG_INFTY/3) /* Complement check for big count */
1082                 {
1083                     vWARN(RExC_parse,
1084                           "Quantifier unexpected on zero-length expression");
1085                 }
1086
1087                 min += minnext * mincount;
1088                 is_inf_internal |= ((maxcount == REG_INFTY
1089                                      && (minnext + deltanext) > 0)
1090                                     || deltanext == I32_MAX);
1091                 is_inf |= is_inf_internal;
1092                 delta += (minnext + deltanext) * maxcount - minnext * mincount;
1093
1094                 /* Try powerful optimization CURLYX => CURLYN. */
1095                 if (  OP(oscan) == CURLYX && data
1096                       && data->flags & SF_IN_PAR
1097                       && !(data->flags & SF_HAS_EVAL)
1098                       && !deltanext && minnext == 1 ) {
1099                     /* Try to optimize to CURLYN.  */
1100                     regnode *nxt = NEXTOPER(oscan) + EXTRA_STEP_2ARGS;
1101                     regnode *nxt1 = nxt, *nxt2;
1102
1103                     /* Skip open. */
1104                     nxt = regnext(nxt);
1105                     if (!strchr((char*)PL_simple,OP(nxt))
1106                         && !(PL_regkind[(U8)OP(nxt)] == EXACT
1107                              && STR_LEN(nxt) == 1))
1108                         goto nogo;
1109                     nxt2 = nxt;
1110                     nxt = regnext(nxt);
1111                     if (OP(nxt) != CLOSE)
1112                         goto nogo;
1113                     /* Now we know that nxt2 is the only contents: */
1114                     oscan->flags = ARG(nxt);
1115                     OP(oscan) = CURLYN;
1116                     OP(nxt1) = NOTHING; /* was OPEN. */
1117 #ifdef DEBUGGING
1118                     OP(nxt1 + 1) = OPTIMIZED; /* was count. */
1119                     NEXT_OFF(nxt1+ 1) = 0; /* just for consistancy. */
1120                     NEXT_OFF(nxt2) = 0; /* just for consistancy with CURLY. */
1121                     OP(nxt) = OPTIMIZED;        /* was CLOSE. */
1122                     OP(nxt + 1) = OPTIMIZED; /* was count. */
1123                     NEXT_OFF(nxt+ 1) = 0; /* just for consistancy. */
1124 #endif
1125                 }
1126               nogo:
1127
1128                 /* Try optimization CURLYX => CURLYM. */
1129                 if (  OP(oscan) == CURLYX && data
1130                       && !(data->flags & SF_HAS_PAR)
1131                       && !(data->flags & SF_HAS_EVAL)
1132                       && !deltanext  ) {
1133                     /* XXXX How to optimize if data == 0? */
1134                     /* Optimize to a simpler form.  */
1135                     regnode *nxt = NEXTOPER(oscan) + EXTRA_STEP_2ARGS; /* OPEN */
1136                     regnode *nxt2;
1137
1138                     OP(oscan) = CURLYM;
1139                     while ( (nxt2 = regnext(nxt)) /* skip over embedded stuff*/
1140                             && (OP(nxt2) != WHILEM))
1141                         nxt = nxt2;
1142                     OP(nxt2)  = SUCCEED; /* Whas WHILEM */
1143                     /* Need to optimize away parenths. */
1144                     if (data->flags & SF_IN_PAR) {
1145                         /* Set the parenth number.  */
1146                         regnode *nxt1 = NEXTOPER(oscan) + EXTRA_STEP_2ARGS; /* OPEN*/
1147
1148                         if (OP(nxt) != CLOSE)
1149                             FAIL("Panic opt close");
1150                         oscan->flags = ARG(nxt);
1151                         OP(nxt1) = OPTIMIZED;   /* was OPEN. */
1152                         OP(nxt) = OPTIMIZED;    /* was CLOSE. */
1153 #ifdef DEBUGGING
1154                         OP(nxt1 + 1) = OPTIMIZED; /* was count. */
1155                         OP(nxt + 1) = OPTIMIZED; /* was count. */
1156                         NEXT_OFF(nxt1 + 1) = 0; /* just for consistancy. */
1157                         NEXT_OFF(nxt + 1) = 0; /* just for consistancy. */
1158 #endif
1159 #if 0
1160                         while ( nxt1 && (OP(nxt1) != WHILEM)) {
1161                             regnode *nnxt = regnext(nxt1);
1162
1163                             if (nnxt == nxt) {
1164                                 if (reg_off_by_arg[OP(nxt1)])
1165                                     ARG_SET(nxt1, nxt2 - nxt1);
1166                                 else if (nxt2 - nxt1 < U16_MAX)
1167                                     NEXT_OFF(nxt1) = nxt2 - nxt1;
1168                                 else
1169                                     OP(nxt) = NOTHING;  /* Cannot beautify */
1170                             }
1171                             nxt1 = nnxt;
1172                         }
1173 #endif
1174                         /* Optimize again: */
1175                         study_chunk(pRExC_state, &nxt1, &deltanext, nxt,
1176                                     NULL, 0);
1177                     }
1178                     else
1179                         oscan->flags = 0;
1180                 }
1181                 else if ((OP(oscan) == CURLYX)
1182                          && (flags & SCF_WHILEM_VISITED_POS)
1183                          /* See the comment on a similar expression above.
1184                             However, this time it not a subexpression
1185                             we care about, but the expression itself. */
1186                          && (maxcount == REG_INFTY)
1187                          && data && ++data->whilem_c < 16) {
1188                     /* This stays as CURLYX, we can put the count/of pair. */
1189                     /* Find WHILEM (as in regexec.c) */
1190                     regnode *nxt = oscan + NEXT_OFF(oscan);
1191
1192                     if (OP(PREVOPER(nxt)) == NOTHING) /* LONGJMP */
1193                         nxt += ARG(nxt);
1194                     PREVOPER(nxt)->flags = data->whilem_c
1195                         | (RExC_whilem_seen << 4); /* On WHILEM */
1196                 }
1197                 if (data && fl & (SF_HAS_PAR|SF_IN_PAR))
1198                     pars++;
1199                 if (flags & SCF_DO_SUBSTR) {
1200                     SV *last_str = Nullsv;
1201                     int counted = mincount != 0;
1202
1203                     if (data->last_end > 0 && mincount != 0) { /* Ends with a string. */
1204                         I32 b = pos_before >= data->last_start_min
1205                             ? pos_before : data->last_start_min;
1206                         STRLEN l;
1207                         char *s = SvPV(data->last_found, l);
1208                         I32 old = b - data->last_start_min;
1209
1210                         if (UTF)
1211                             old = utf8_hop((U8*)s, old) - (U8*)s;
1212
1213                         l -= old;
1214                         /* Get the added string: */
1215                         last_str = newSVpvn(s  + old, l);
1216                         if (deltanext == 0 && pos_before == b) {
1217                             /* What was added is a constant string */
1218                             if (mincount > 1) {
1219                                 SvGROW(last_str, (mincount * l) + 1);
1220                                 repeatcpy(SvPVX(last_str) + l,
1221                                           SvPVX(last_str), l, mincount - 1);
1222                                 SvCUR(last_str) *= mincount;
1223                                 /* Add additional parts. */
1224                                 SvCUR_set(data->last_found,
1225                                           SvCUR(data->last_found) - l);
1226                                 sv_catsv(data->last_found, last_str);
1227                                 data->last_end += l * (mincount - 1);
1228                             }
1229                         } else {
1230                             /* start offset must point into the last copy */
1231                             data->last_start_min += minnext * (mincount - 1);
1232                             data->last_start_max += is_inf ? 0 : (maxcount - 1)
1233                                 * (minnext + data->pos_delta);
1234                         }
1235                     }
1236                     /* It is counted once already... */
1237                     data->pos_min += minnext * (mincount - counted);
1238                     data->pos_delta += - counted * deltanext +
1239                         (minnext + deltanext) * maxcount - minnext * mincount;
1240                     if (mincount != maxcount) {
1241                          /* Cannot extend fixed substrings found inside
1242                             the group.  */
1243                         scan_commit(pRExC_state,data);
1244                         if (mincount && last_str) {
1245                             sv_setsv(data->last_found, last_str);
1246                             data->last_end = data->pos_min;
1247                             data->last_start_min =
1248                                 data->pos_min - CHR_SVLEN(last_str);
1249                             data->last_start_max = is_inf
1250                                 ? I32_MAX
1251                                 : data->pos_min + data->pos_delta
1252                                 - CHR_SVLEN(last_str);
1253                         }
1254                         data->longest = &(data->longest_float);
1255                     }
1256                     SvREFCNT_dec(last_str);
1257                 }
1258                 if (data && (fl & SF_HAS_EVAL))
1259                     data->flags |= SF_HAS_EVAL;
1260               optimize_curly_tail:
1261                 if (OP(oscan) != CURLYX) {
1262                     while (PL_regkind[(U8)OP(next = regnext(oscan))] == NOTHING
1263                            && NEXT_OFF(next))
1264                         NEXT_OFF(oscan) += NEXT_OFF(next);
1265                 }
1266                 continue;
1267             default:                    /* REF and CLUMP only? */
1268                 if (flags & SCF_DO_SUBSTR) {
1269                     scan_commit(pRExC_state,data);      /* Cannot expect anything... */
1270                     data->longest = &(data->longest_float);
1271                 }
1272                 is_inf = is_inf_internal = 1;
1273                 if (flags & SCF_DO_STCLASS_OR)
1274                     cl_anything(pRExC_state, data->start_class);
1275                 flags &= ~SCF_DO_STCLASS;
1276                 break;
1277             }
1278         }
1279         else if (strchr((char*)PL_simple,OP(scan))) {
1280             int value = 0;
1281
1282             if (flags & SCF_DO_SUBSTR) {
1283                 scan_commit(pRExC_state,data);
1284                 data->pos_min++;
1285             }
1286             min++;
1287             if (flags & SCF_DO_STCLASS) {
1288                 data->start_class->flags &= ~ANYOF_EOS; /* No match on empty */
1289
1290                 /* Some of the logic below assumes that switching
1291                    locale on will only add false positives. */
1292                 switch (PL_regkind[(U8)OP(scan)]) {
1293                 case SANY:
1294                 default:
1295                   do_default:
1296                     /* Perl_croak(aTHX_ "panic: unexpected simple REx opcode %d", OP(scan)); */
1297                     if (flags & SCF_DO_STCLASS_OR) /* Allow everything */
1298                         cl_anything(pRExC_state, data->start_class);
1299                     break;
1300                 case REG_ANY:
1301                     if (OP(scan) == SANY)
1302                         goto do_default;
1303                     if (flags & SCF_DO_STCLASS_OR) { /* Everything but \n */
1304                         value = (ANYOF_BITMAP_TEST(data->start_class,'\n')
1305                                  || (data->start_class->flags & ANYOF_CLASS));
1306                         cl_anything(pRExC_state, data->start_class);
1307                     }
1308                     if (flags & SCF_DO_STCLASS_AND || !value)
1309                         ANYOF_BITMAP_CLEAR(data->start_class,'\n');
1310                     break;
1311                 case ANYOF:
1312                     if (flags & SCF_DO_STCLASS_AND)
1313                         cl_and(data->start_class,
1314                                (struct regnode_charclass_class*)scan);
1315                     else
1316                         cl_or(pRExC_state, data->start_class,
1317                               (struct regnode_charclass_class*)scan);
1318                     break;
1319                 case ALNUM:
1320                     if (flags & SCF_DO_STCLASS_AND) {
1321                         if (!(data->start_class->flags & ANYOF_LOCALE)) {
1322                             ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NALNUM);
1323                             for (value = 0; value < 256; value++)
1324                                 if (!isALNUM(value))
1325                                     ANYOF_BITMAP_CLEAR(data->start_class, value);
1326                         }
1327                     }
1328                     else {
1329                         if (data->start_class->flags & ANYOF_LOCALE)
1330                             ANYOF_CLASS_SET(data->start_class,ANYOF_ALNUM);
1331                         else {
1332                             for (value = 0; value < 256; value++)
1333                                 if (isALNUM(value))
1334                                     ANYOF_BITMAP_SET(data->start_class, value);
1335                         }
1336                     }
1337                     break;
1338                 case ALNUML:
1339                     if (flags & SCF_DO_STCLASS_AND) {
1340                         if (data->start_class->flags & ANYOF_LOCALE)
1341                             ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NALNUM);
1342                     }
1343                     else {
1344                         ANYOF_CLASS_SET(data->start_class,ANYOF_ALNUM);
1345                         data->start_class->flags |= ANYOF_LOCALE;
1346                     }
1347                     break;
1348                 case NALNUM:
1349                     if (flags & SCF_DO_STCLASS_AND) {
1350                         if (!(data->start_class->flags & ANYOF_LOCALE)) {
1351                             ANYOF_CLASS_CLEAR(data->start_class,ANYOF_ALNUM);
1352                             for (value = 0; value < 256; value++)
1353                                 if (isALNUM(value))
1354                                     ANYOF_BITMAP_CLEAR(data->start_class, value);
1355                         }
1356                     }
1357                     else {
1358                         if (data->start_class->flags & ANYOF_LOCALE)
1359                             ANYOF_CLASS_SET(data->start_class,ANYOF_NALNUM);
1360                         else {
1361                             for (value = 0; value < 256; value++)
1362                                 if (!isALNUM(value))
1363                                     ANYOF_BITMAP_SET(data->start_class, value);
1364                         }
1365                     }
1366                     break;
1367                 case NALNUML:
1368                     if (flags & SCF_DO_STCLASS_AND) {
1369                         if (data->start_class->flags & ANYOF_LOCALE)
1370                             ANYOF_CLASS_CLEAR(data->start_class,ANYOF_ALNUM);
1371                     }
1372                     else {
1373                         data->start_class->flags |= ANYOF_LOCALE;
1374                         ANYOF_CLASS_SET(data->start_class,ANYOF_NALNUM);
1375                     }
1376                     break;
1377                 case SPACE:
1378                     if (flags & SCF_DO_STCLASS_AND) {
1379                         if (!(data->start_class->flags & ANYOF_LOCALE)) {
1380                             ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NSPACE);
1381                             for (value = 0; value < 256; value++)
1382                                 if (!isSPACE(value))
1383                                     ANYOF_BITMAP_CLEAR(data->start_class, value);
1384                         }
1385                     }
1386                     else {
1387                         if (data->start_class->flags & ANYOF_LOCALE)
1388                             ANYOF_CLASS_SET(data->start_class,ANYOF_SPACE);
1389                         else {
1390                             for (value = 0; value < 256; value++)
1391                                 if (isSPACE(value))
1392                                     ANYOF_BITMAP_SET(data->start_class, value);
1393                         }
1394                     }
1395                     break;
1396                 case SPACEL:
1397                     if (flags & SCF_DO_STCLASS_AND) {
1398                         if (data->start_class->flags & ANYOF_LOCALE)
1399                             ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NSPACE);
1400                     }
1401                     else {
1402                         data->start_class->flags |= ANYOF_LOCALE;
1403                         ANYOF_CLASS_SET(data->start_class,ANYOF_SPACE);
1404                     }
1405                     break;
1406                 case NSPACE:
1407                     if (flags & SCF_DO_STCLASS_AND) {
1408                         if (!(data->start_class->flags & ANYOF_LOCALE)) {
1409                             ANYOF_CLASS_CLEAR(data->start_class,ANYOF_SPACE);
1410                             for (value = 0; value < 256; value++)
1411                                 if (isSPACE(value))
1412                                     ANYOF_BITMAP_CLEAR(data->start_class, value);
1413                         }
1414                     }
1415                     else {
1416                         if (data->start_class->flags & ANYOF_LOCALE)
1417                             ANYOF_CLASS_SET(data->start_class,ANYOF_NSPACE);
1418                         else {
1419                             for (value = 0; value < 256; value++)
1420                                 if (!isSPACE(value))
1421                                     ANYOF_BITMAP_SET(data->start_class, value);
1422                         }
1423                     }
1424                     break;
1425                 case NSPACEL:
1426                     if (flags & SCF_DO_STCLASS_AND) {
1427                         if (data->start_class->flags & ANYOF_LOCALE) {
1428                             ANYOF_CLASS_CLEAR(data->start_class,ANYOF_SPACE);
1429                             for (value = 0; value < 256; value++)
1430                                 if (!isSPACE(value))
1431                                     ANYOF_BITMAP_CLEAR(data->start_class, value);
1432                         }
1433                     }
1434                     else {
1435                         data->start_class->flags |= ANYOF_LOCALE;
1436                         ANYOF_CLASS_SET(data->start_class,ANYOF_NSPACE);
1437                     }
1438                     break;
1439                 case DIGIT:
1440                     if (flags & SCF_DO_STCLASS_AND) {
1441                         ANYOF_CLASS_CLEAR(data->start_class,ANYOF_NDIGIT);
1442                         for (value = 0; value < 256; value++)
1443                             if (!isDIGIT(value))
1444                                 ANYOF_BITMAP_CLEAR(data->start_class, value);
1445                     }
1446                     else {
1447                         if (data->start_class->flags & ANYOF_LOCALE)
1448                             ANYOF_CLASS_SET(data->start_class,ANYOF_DIGIT);
1449                         else {
1450                             for (value = 0; value < 256; value++)
1451                                 if (isDIGIT(value))
1452                                     ANYOF_BITMAP_SET(data->start_class, value);
1453                         }
1454                     }
1455                     break;
1456                 case NDIGIT:
1457                     if (flags & SCF_DO_STCLASS_AND) {
1458                         ANYOF_CLASS_CLEAR(data->start_class,ANYOF_DIGIT);
1459                         for (value = 0; value < 256; value++)
1460                             if (isDIGIT(value))
1461                                 ANYOF_BITMAP_CLEAR(data->start_class, value);
1462                     }
1463                     else {
1464                         if (data->start_class->flags & ANYOF_LOCALE)
1465                             ANYOF_CLASS_SET(data->start_class,ANYOF_NDIGIT);
1466                         else {
1467                             for (value = 0; value < 256; value++)
1468                                 if (!isDIGIT(value))
1469                                     ANYOF_BITMAP_SET(data->start_class, value);
1470                         }
1471                     }
1472                     break;
1473                 }
1474                 if (flags & SCF_DO_STCLASS_OR)
1475                     cl_and(data->start_class, &and_with);
1476                 flags &= ~SCF_DO_STCLASS;
1477             }
1478         }
1479         else if (PL_regkind[(U8)OP(scan)] == EOL && flags & SCF_DO_SUBSTR) {
1480             data->flags |= (OP(scan) == MEOL
1481                             ? SF_BEFORE_MEOL
1482                             : SF_BEFORE_SEOL);
1483         }
1484         else if (  PL_regkind[(U8)OP(scan)] == BRANCHJ
1485                  /* Lookbehind, or need to calculate parens/evals/stclass: */
1486                    && (scan->flags || data || (flags & SCF_DO_STCLASS))
1487                    && (OP(scan) == IFMATCH || OP(scan) == UNLESSM)) {
1488             /* Lookahead/lookbehind */
1489             I32 deltanext, minnext, fake = 0;
1490             regnode *nscan;
1491             struct regnode_charclass_class intrnl;
1492             int f = 0;
1493
1494             data_fake.flags = 0;
1495             if (data) {
1496                 data_fake.whilem_c = data->whilem_c;
1497                 data_fake.last_closep = data->last_closep;
1498             }
1499             else
1500                 data_fake.last_closep = &fake;
1501             if ( flags & SCF_DO_STCLASS && !scan->flags
1502                  && OP(scan) == IFMATCH ) { /* Lookahead */
1503                 cl_init(pRExC_state, &intrnl);
1504                 data_fake.start_class = &intrnl;
1505                 f |= SCF_DO_STCLASS_AND;
1506             }
1507             if (flags & SCF_WHILEM_VISITED_POS)
1508                 f |= SCF_WHILEM_VISITED_POS;
1509             next = regnext(scan);
1510             nscan = NEXTOPER(NEXTOPER(scan));
1511             minnext = study_chunk(pRExC_state, &nscan, &deltanext, last, &data_fake, f);
1512             if (scan->flags) {
1513                 if (deltanext) {
1514                     vFAIL("Variable length lookbehind not implemented");
1515                 }
1516                 else if (minnext > U8_MAX) {
1517                     vFAIL2("Lookbehind longer than %"UVuf" not implemented", (UV)U8_MAX);
1518                 }
1519                 scan->flags = minnext;
1520             }
1521             if (data && data_fake.flags & (SF_HAS_PAR|SF_IN_PAR))
1522                 pars++;
1523             if (data && (data_fake.flags & SF_HAS_EVAL))
1524                 data->flags |= SF_HAS_EVAL;
1525             if (data)
1526                 data->whilem_c = data_fake.whilem_c;
1527             if (f & SCF_DO_STCLASS_AND) {
1528                 int was = (data->start_class->flags & ANYOF_EOS);
1529
1530                 cl_and(data->start_class, &intrnl);
1531                 if (was)
1532                     data->start_class->flags |= ANYOF_EOS;
1533             }
1534         }
1535         else if (OP(scan) == OPEN) {
1536             pars++;
1537         }
1538         else if (OP(scan) == CLOSE) {
1539             if (ARG(scan) == is_par) {
1540                 next = regnext(scan);
1541
1542                 if ( next && (OP(next) != WHILEM) && next < last)
1543                     is_par = 0;         /* Disable optimization */
1544             }
1545             if (data)
1546                 *(data->last_closep) = ARG(scan);
1547         }
1548         else if (OP(scan) == EVAL) {
1549                 if (data)
1550                     data->flags |= SF_HAS_EVAL;
1551         }
1552         else if (OP(scan) == LOGICAL && scan->flags == 2) { /* Embedded follows */
1553                 if (flags & SCF_DO_SUBSTR) {
1554                     scan_commit(pRExC_state,data);
1555                     data->longest = &(data->longest_float);
1556                 }
1557                 is_inf = is_inf_internal = 1;
1558                 if (flags & SCF_DO_STCLASS_OR) /* Allow everything */
1559                     cl_anything(pRExC_state, data->start_class);
1560                 flags &= ~SCF_DO_STCLASS;
1561         }
1562         /* Else: zero-length, ignore. */
1563         scan = regnext(scan);
1564     }
1565
1566   finish:
1567     *scanp = scan;
1568     *deltap = is_inf_internal ? I32_MAX : delta;
1569     if (flags & SCF_DO_SUBSTR && is_inf)
1570         data->pos_delta = I32_MAX - data->pos_min;
1571     if (is_par > U8_MAX)
1572         is_par = 0;
1573     if (is_par && pars==1 && data) {
1574         data->flags |= SF_IN_PAR;
1575         data->flags &= ~SF_HAS_PAR;
1576     }
1577     else if (pars && data) {
1578         data->flags |= SF_HAS_PAR;
1579         data->flags &= ~SF_IN_PAR;
1580     }
1581     if (flags & SCF_DO_STCLASS_OR)
1582         cl_and(data->start_class, &and_with);
1583     return min;
1584 }
1585
1586 STATIC I32
1587 S_add_data(pTHX_ RExC_state_t *pRExC_state, I32 n, char *s)
1588 {
1589     if (RExC_rx->data) {
1590         Renewc(RExC_rx->data,
1591                sizeof(*RExC_rx->data) + sizeof(void*) * (RExC_rx->data->count + n - 1),
1592                char, struct reg_data);
1593         Renew(RExC_rx->data->what, RExC_rx->data->count + n, U8);
1594         RExC_rx->data->count += n;
1595     }
1596     else {
1597         Newc(1207, RExC_rx->data, sizeof(*RExC_rx->data) + sizeof(void*) * (n - 1),
1598              char, struct reg_data);
1599         New(1208, RExC_rx->data->what, n, U8);
1600         RExC_rx->data->count = n;
1601     }
1602     Copy(s, RExC_rx->data->what + RExC_rx->data->count - n, n, U8);
1603     return RExC_rx->data->count - n;
1604 }
1605
1606 void
1607 Perl_reginitcolors(pTHX)
1608 {
1609     int i = 0;
1610     char *s = PerlEnv_getenv("PERL_RE_COLORS");
1611
1612     if (s) {
1613         PL_colors[0] = s = savepv(s);
1614         while (++i < 6) {
1615             s = strchr(s, '\t');
1616             if (s) {
1617                 *s = '\0';
1618                 PL_colors[i] = ++s;
1619             }
1620             else
1621                 PL_colors[i] = s = "";
1622         }
1623     } else {
1624         while (i < 6)
1625             PL_colors[i++] = "";
1626     }
1627     PL_colorset = 1;
1628 }
1629
1630
1631 /*
1632  - pregcomp - compile a regular expression into internal code
1633  *
1634  * We can't allocate space until we know how big the compiled form will be,
1635  * but we can't compile it (and thus know how big it is) until we've got a
1636  * place to put the code.  So we cheat:  we compile it twice, once with code
1637  * generation turned off and size counting turned on, and once "for real".
1638  * This also means that we don't allocate space until we are sure that the
1639  * thing really will compile successfully, and we never have to move the
1640  * code and thus invalidate pointers into it.  (Note that it has to be in
1641  * one piece because free() must be able to free it all.) [NB: not true in perl]
1642  *
1643  * Beware that the optimization-preparation code in here knows about some
1644  * of the structure of the compiled regexp.  [I'll say.]
1645  */
1646 regexp *
1647 Perl_pregcomp(pTHX_ char *exp, char *xend, PMOP *pm)
1648 {
1649     register regexp *r;
1650     regnode *scan;
1651     regnode *first;
1652     I32 flags;
1653     I32 minlen = 0;
1654     I32 sawplus = 0;
1655     I32 sawopen = 0;
1656     scan_data_t data;
1657     RExC_state_t RExC_state;
1658     RExC_state_t *pRExC_state = &RExC_state;
1659
1660     if (exp == NULL)
1661         FAIL("NULL regexp argument");
1662
1663     /* XXXX This looks very suspicious... */
1664     if (pm->op_pmdynflags & PMdf_CMP_UTF8)
1665         RExC_utf8 = 1;
1666     else
1667         RExC_utf8 = 0;
1668
1669     RExC_precomp = exp;
1670     DEBUG_r(if (!PL_colorset) reginitcolors());
1671     DEBUG_r(PerlIO_printf(Perl_debug_log, "%sCompiling REx%s `%s%*s%s'\n",
1672                       PL_colors[4],PL_colors[5],PL_colors[0],
1673                       (int)(xend - exp), RExC_precomp, PL_colors[1]));
1674     RExC_flags16 = pm->op_pmflags;
1675     RExC_sawback = 0;
1676
1677     RExC_seen = 0;
1678     RExC_seen_zerolen = *exp == '^' ? -1 : 0;
1679     RExC_seen_evals = 0;
1680     RExC_extralen = 0;
1681
1682     /* First pass: determine size, legality. */
1683     RExC_parse = exp;
1684     RExC_start = exp;
1685     RExC_end = xend;
1686     RExC_naughty = 0;
1687     RExC_npar = 1;
1688     RExC_size = 0L;
1689     RExC_emit = &PL_regdummy;
1690     RExC_whilem_seen = 0;
1691 #if 0 /* REGC() is (currently) a NOP at the first pass.
1692        * Clever compilers notice this and complain. --jhi */
1693     REGC((U8)REG_MAGIC, (char*)RExC_emit);
1694 #endif
1695     if (reg(pRExC_state, 0, &flags) == NULL) {
1696         RExC_precomp = Nullch;
1697         return(NULL);
1698     }
1699     DEBUG_r(PerlIO_printf(Perl_debug_log, "size %"IVdf" ", (IV)RExC_size));
1700
1701     /* Small enough for pointer-storage convention?
1702        If extralen==0, this means that we will not need long jumps. */
1703     if (RExC_size >= 0x10000L && RExC_extralen)
1704         RExC_size += RExC_extralen;
1705     else
1706         RExC_extralen = 0;
1707     if (RExC_whilem_seen > 15)
1708         RExC_whilem_seen = 15;
1709
1710     /* Allocate space and initialize. */
1711     Newc(1001, r, sizeof(regexp) + (unsigned)RExC_size * sizeof(regnode),
1712          char, regexp);
1713     if (r == NULL)
1714         FAIL("Regexp out of space");
1715
1716 #ifdef DEBUGGING
1717     /* avoid reading uninitialized memory in DEBUGGING code in study_chunk() */
1718     Zero(r, sizeof(regexp) + (unsigned)RExC_size * sizeof(regnode), char);
1719 #endif
1720     r->refcnt = 1;
1721     r->prelen = xend - exp;
1722     r->precomp = savepvn(RExC_precomp, r->prelen);
1723     r->subbeg = NULL;
1724     r->reganch = pm->op_pmflags & PMf_COMPILETIME;
1725     r->nparens = RExC_npar - 1; /* set early to validate backrefs */
1726
1727     r->substrs = 0;                     /* Useful during FAIL. */
1728     r->startp = 0;                      /* Useful during FAIL. */
1729     r->endp = 0;                        /* Useful during FAIL. */
1730
1731     Newz(1304, r->offsets, 2*RExC_size+1, U32); /* MJD 20001228 */
1732     if (r->offsets) {
1733       r->offsets[0] = RExC_size;
1734     }
1735     DEBUG_r(PerlIO_printf(Perl_debug_log,
1736                           "%s %"UVuf" bytes for offset annotations.\n",
1737                           r->offsets ? "Got" : "Couldn't get",
1738                           (UV)((2*RExC_size+1) * sizeof(U32))));
1739
1740     RExC_rx = r;
1741
1742     /* Second pass: emit code. */
1743     RExC_parse = exp;
1744     RExC_end = xend;
1745     RExC_naughty = 0;
1746     RExC_npar = 1;
1747     RExC_emit_start = r->program;
1748     RExC_emit = r->program;
1749     /* Store the count of eval-groups for security checks: */
1750     RExC_emit->next_off = ((RExC_seen_evals > U16_MAX) ? U16_MAX : RExC_seen_evals);
1751     REGC((U8)REG_MAGIC, (char*) RExC_emit++);
1752     r->data = 0;
1753     if (reg(pRExC_state, 0, &flags) == NULL)
1754         return(NULL);
1755
1756     /* Dig out information for optimizations. */
1757     r->reganch = pm->op_pmflags & PMf_COMPILETIME; /* Again? */
1758     pm->op_pmflags = RExC_flags16;
1759     if (UTF)
1760         r->reganch |= ROPT_UTF8;
1761     r->regstclass = NULL;
1762     if (RExC_naughty >= 10)     /* Probably an expensive pattern. */
1763         r->reganch |= ROPT_NAUGHTY;
1764     scan = r->program + 1;              /* First BRANCH. */
1765
1766     /* XXXX To minimize changes to RE engine we always allocate
1767        3-units-long substrs field. */
1768     Newz(1004, r->substrs, 1, struct reg_substr_data);
1769
1770     StructCopy(&zero_scan_data, &data, scan_data_t);
1771     /* XXXX Should not we check for something else?  Usually it is OPEN1... */
1772     if (OP(scan) != BRANCH) {   /* Only one top-level choice. */
1773         I32 fake;
1774         STRLEN longest_float_length, longest_fixed_length;
1775         struct regnode_charclass_class ch_class;
1776         int stclass_flag;
1777         I32 last_close = 0;
1778
1779         first = scan;
1780         /* Skip introductions and multiplicators >= 1. */
1781         while ((OP(first) == OPEN && (sawopen = 1)) ||
1782                /* An OR of *one* alternative - should not happen now. */
1783             (OP(first) == BRANCH && OP(regnext(first)) != BRANCH) ||
1784             (OP(first) == PLUS) ||
1785             (OP(first) == MINMOD) ||
1786                /* An {n,m} with n>0 */
1787             (PL_regkind[(U8)OP(first)] == CURLY && ARG1(first) > 0) ) {
1788                 if (OP(first) == PLUS)
1789                     sawplus = 1;
1790                 else
1791                     first += regarglen[(U8)OP(first)];
1792                 first = NEXTOPER(first);
1793         }
1794
1795         /* Starting-point info. */
1796       again:
1797         if (PL_regkind[(U8)OP(first)] == EXACT) {
1798             if (OP(first) == EXACT)
1799                 ;       /* Empty, get anchored substr later. */
1800             else if ((OP(first) == EXACTF || OP(first) == EXACTFL))
1801                 r->regstclass = first;
1802         }
1803         else if (strchr((char*)PL_simple,OP(first)))
1804             r->regstclass = first;
1805         else if (PL_regkind[(U8)OP(first)] == BOUND ||
1806                  PL_regkind[(U8)OP(first)] == NBOUND)
1807             r->regstclass = first;
1808         else if (PL_regkind[(U8)OP(first)] == BOL) {
1809             r->reganch |= (OP(first) == MBOL
1810                            ? ROPT_ANCH_MBOL
1811                            : (OP(first) == SBOL
1812                               ? ROPT_ANCH_SBOL
1813                               : ROPT_ANCH_BOL));
1814             first = NEXTOPER(first);
1815             goto again;
1816         }
1817         else if (OP(first) == GPOS) {
1818             r->reganch |= ROPT_ANCH_GPOS;
1819             first = NEXTOPER(first);
1820             goto again;
1821         }
1822         else if ((OP(first) == STAR &&
1823             PL_regkind[(U8)OP(NEXTOPER(first))] == REG_ANY) &&
1824             !(r->reganch & ROPT_ANCH) )
1825         {
1826             /* turn .* into ^.* with an implied $*=1 */
1827             int type = OP(NEXTOPER(first));
1828
1829             if (type == REG_ANY)
1830                 type = ROPT_ANCH_MBOL;
1831             else
1832                 type = ROPT_ANCH_SBOL;
1833
1834             r->reganch |= type | ROPT_IMPLICIT;
1835             first = NEXTOPER(first);
1836             goto again;
1837         }
1838         if (sawplus && (!sawopen || !RExC_sawback)
1839             && !(RExC_seen & REG_SEEN_EVAL)) /* May examine pos and $& */
1840             /* x+ must match at the 1st pos of run of x's */
1841             r->reganch |= ROPT_SKIP;
1842
1843         /* Scan is after the zeroth branch, first is atomic matcher. */
1844         DEBUG_r(PerlIO_printf(Perl_debug_log, "first at %"IVdf"\n",
1845                               (IV)(first - scan + 1)));
1846         /*
1847         * If there's something expensive in the r.e., find the
1848         * longest literal string that must appear and make it the
1849         * regmust.  Resolve ties in favor of later strings, since
1850         * the regstart check works with the beginning of the r.e.
1851         * and avoiding duplication strengthens checking.  Not a
1852         * strong reason, but sufficient in the absence of others.
1853         * [Now we resolve ties in favor of the earlier string if
1854         * it happens that c_offset_min has been invalidated, since the
1855         * earlier string may buy us something the later one won't.]
1856         */
1857         minlen = 0;
1858
1859         data.longest_fixed = newSVpvn("",0);
1860         data.longest_float = newSVpvn("",0);
1861         data.last_found = newSVpvn("",0);
1862         data.longest = &(data.longest_fixed);
1863         first = scan;
1864         if (!r->regstclass) {
1865             cl_init(pRExC_state, &ch_class);
1866             data.start_class = &ch_class;
1867             stclass_flag = SCF_DO_STCLASS_AND;
1868         } else                          /* XXXX Check for BOUND? */
1869             stclass_flag = 0;
1870         data.last_closep = &last_close;
1871
1872         minlen = study_chunk(pRExC_state, &first, &fake, scan + RExC_size, /* Up to end */
1873                              &data, SCF_DO_SUBSTR | SCF_WHILEM_VISITED_POS | stclass_flag);
1874         if ( RExC_npar == 1 && data.longest == &(data.longest_fixed)
1875              && data.last_start_min == 0 && data.last_end > 0
1876              && !RExC_seen_zerolen
1877              && (!(RExC_seen & REG_SEEN_GPOS) || (r->reganch & ROPT_ANCH_GPOS)))
1878             r->reganch |= ROPT_CHECK_ALL;
1879         scan_commit(pRExC_state, &data);
1880         SvREFCNT_dec(data.last_found);
1881
1882         longest_float_length = CHR_SVLEN(data.longest_float);
1883         if (longest_float_length
1884             || (data.flags & SF_FL_BEFORE_EOL
1885                 && (!(data.flags & SF_FL_BEFORE_MEOL)
1886                     || (RExC_flags16 & PMf_MULTILINE)))) {
1887             int t;
1888
1889             if (SvCUR(data.longest_fixed)                       /* ok to leave SvCUR */
1890                 && data.offset_fixed == data.offset_float_min
1891                 && SvCUR(data.longest_fixed) == SvCUR(data.longest_float))
1892                     goto remove_float;          /* As in (a)+. */
1893
1894             r->float_substr = data.longest_float;
1895             r->float_min_offset = data.offset_float_min;
1896             r->float_max_offset = data.offset_float_max;
1897             t = (data.flags & SF_FL_BEFORE_EOL /* Can't have SEOL and MULTI */
1898                        && (!(data.flags & SF_FL_BEFORE_MEOL)
1899                            || (RExC_flags16 & PMf_MULTILINE)));
1900             fbm_compile(r->float_substr, t ? FBMcf_TAIL : 0);
1901         }
1902         else {
1903           remove_float:
1904             r->float_substr = Nullsv;
1905             SvREFCNT_dec(data.longest_float);
1906             longest_float_length = 0;
1907         }
1908
1909         longest_fixed_length = CHR_SVLEN(data.longest_fixed);
1910         if (longest_fixed_length
1911             || (data.flags & SF_FIX_BEFORE_EOL /* Cannot have SEOL and MULTI */
1912                 && (!(data.flags & SF_FIX_BEFORE_MEOL)
1913                     || (RExC_flags16 & PMf_MULTILINE)))) {
1914             int t;
1915
1916             r->anchored_substr = data.longest_fixed;
1917             r->anchored_offset = data.offset_fixed;
1918             t = (data.flags & SF_FIX_BEFORE_EOL /* Can't have SEOL and MULTI */
1919                  && (!(data.flags & SF_FIX_BEFORE_MEOL)
1920                      || (RExC_flags16 & PMf_MULTILINE)));
1921             fbm_compile(r->anchored_substr, t ? FBMcf_TAIL : 0);
1922         }
1923         else {
1924             r->anchored_substr = Nullsv;
1925             SvREFCNT_dec(data.longest_fixed);
1926             longest_fixed_length = 0;
1927         }
1928         if (r->regstclass
1929             && (OP(r->regstclass) == REG_ANY || OP(r->regstclass) == SANY))
1930             r->regstclass = NULL;
1931         if ((!r->anchored_substr || r->anchored_offset) && stclass_flag
1932             && !(data.start_class->flags & ANYOF_EOS)
1933             && !cl_is_anything(data.start_class)) {
1934             I32 n = add_data(pRExC_state, 1, "f");
1935
1936             New(1006, RExC_rx->data->data[n], 1,
1937                 struct regnode_charclass_class);
1938             StructCopy(data.start_class,
1939                        (struct regnode_charclass_class*)RExC_rx->data->data[n],
1940                        struct regnode_charclass_class);
1941             r->regstclass = (regnode*)RExC_rx->data->data[n];
1942             r->reganch &= ~ROPT_SKIP;   /* Used in find_byclass(). */
1943             PL_regdata = r->data; /* for regprop() */
1944             DEBUG_r({ SV *sv = sv_newmortal();
1945                       regprop(sv, (regnode*)data.start_class);
1946                       PerlIO_printf(Perl_debug_log,
1947                                     "synthetic stclass `%s'.\n",
1948                                     SvPVX(sv));});
1949         }
1950
1951         /* A temporary algorithm prefers floated substr to fixed one to dig more info. */
1952         if (longest_fixed_length > longest_float_length) {
1953             r->check_substr = r->anchored_substr;
1954             r->check_offset_min = r->check_offset_max = r->anchored_offset;
1955             if (r->reganch & ROPT_ANCH_SINGLE)
1956                 r->reganch |= ROPT_NOSCAN;
1957         }
1958         else {
1959             r->check_substr = r->float_substr;
1960             r->check_offset_min = data.offset_float_min;
1961             r->check_offset_max = data.offset_float_max;
1962         }
1963         /* XXXX Currently intuiting is not compatible with ANCH_GPOS.
1964            This should be changed ASAP!  */
1965         if (r->check_substr && !(r->reganch & ROPT_ANCH_GPOS)) {
1966             r->reganch |= RE_USE_INTUIT;
1967             if (SvTAIL(r->check_substr))
1968                 r->reganch |= RE_INTUIT_TAIL;
1969         }
1970     }
1971     else {
1972         /* Several toplevels. Best we can is to set minlen. */
1973         I32 fake;
1974         struct regnode_charclass_class ch_class;
1975         I32 last_close = 0;
1976
1977         DEBUG_r(PerlIO_printf(Perl_debug_log, "\n"));
1978         scan = r->program + 1;
1979         cl_init(pRExC_state, &ch_class);
1980         data.start_class = &ch_class;
1981         data.last_closep = &last_close;
1982         minlen = study_chunk(pRExC_state, &scan, &fake, scan + RExC_size, &data, SCF_DO_STCLASS_AND|SCF_WHILEM_VISITED_POS);
1983         r->check_substr = r->anchored_substr = r->float_substr = Nullsv;
1984         if (!(data.start_class->flags & ANYOF_EOS)
1985             && !cl_is_anything(data.start_class)) {
1986             I32 n = add_data(pRExC_state, 1, "f");
1987
1988             New(1006, RExC_rx->data->data[n], 1,
1989                 struct regnode_charclass_class);
1990             StructCopy(data.start_class,
1991                        (struct regnode_charclass_class*)RExC_rx->data->data[n],
1992                        struct regnode_charclass_class);
1993             r->regstclass = (regnode*)RExC_rx->data->data[n];
1994             r->reganch &= ~ROPT_SKIP;   /* Used in find_byclass(). */
1995             DEBUG_r({ SV* sv = sv_newmortal();
1996                       regprop(sv, (regnode*)data.start_class);
1997                       PerlIO_printf(Perl_debug_log,
1998                                     "synthetic stclass `%s'.\n",
1999                                     SvPVX(sv));});
2000         }
2001     }
2002
2003     r->minlen = minlen;
2004     if (RExC_seen & REG_SEEN_GPOS)
2005         r->reganch |= ROPT_GPOS_SEEN;
2006     if (RExC_seen & REG_SEEN_LOOKBEHIND)
2007         r->reganch |= ROPT_LOOKBEHIND_SEEN;
2008     if (RExC_seen & REG_SEEN_EVAL)
2009         r->reganch |= ROPT_EVAL_SEEN;
2010     if (RExC_seen & REG_SEEN_SANY)
2011         r->reganch |= ROPT_SANY_SEEN;
2012     Newz(1002, r->startp, RExC_npar, I32);
2013     Newz(1002, r->endp, RExC_npar, I32);
2014     PL_regdata = r->data; /* for regprop() */
2015     DEBUG_r(regdump(r));
2016     return(r);
2017 }
2018
2019 /*
2020  - reg - regular expression, i.e. main body or parenthesized thing
2021  *
2022  * Caller must absorb opening parenthesis.
2023  *
2024  * Combining parenthesis handling with the base level of regular expression
2025  * is a trifle forced, but the need to tie the tails of the branches to what
2026  * follows makes it hard to avoid.
2027  */
2028 STATIC regnode *
2029 S_reg(pTHX_ RExC_state_t *pRExC_state, I32 paren, I32 *flagp)
2030     /* paren: Parenthesized? 0=top, 1=(, inside: changed to letter. */
2031 {
2032     register regnode *ret;              /* Will be the head of the group. */
2033     register regnode *br;
2034     register regnode *lastbr;
2035     register regnode *ender = 0;
2036     register I32 parno = 0;
2037     I32 flags, oregflags = RExC_flags16, have_branch = 0, open = 0;
2038
2039     /* for (?g), (?gc), and (?o) warnings; warning
2040        about (?c) will warn about (?g) -- japhy    */
2041
2042     I32 wastedflags = 0x00,
2043         wasted_o    = 0x01,
2044         wasted_g    = 0x02,
2045         wasted_gc   = 0x02 | 0x04,
2046         wasted_c    = 0x04;
2047
2048     char * parse_start = RExC_parse; /* MJD */
2049     char *oregcomp_parse = RExC_parse;
2050     char c;
2051
2052     *flagp = 0;                         /* Tentatively. */
2053
2054
2055     /* Make an OPEN node, if parenthesized. */
2056     if (paren) {
2057         if (*RExC_parse == '?') { /* (?...) */
2058             U16 posflags = 0, negflags = 0;
2059             U16 *flagsp = &posflags;
2060             int logical = 0;
2061             char *seqstart = RExC_parse;
2062
2063             RExC_parse++;
2064             paren = *RExC_parse++;
2065             ret = NULL;                 /* For look-ahead/behind. */
2066             switch (paren) {
2067             case '<':           /* (?<...) */
2068                 RExC_seen |= REG_SEEN_LOOKBEHIND;
2069                 if (*RExC_parse == '!')
2070                     paren = ',';
2071                 if (*RExC_parse != '=' && *RExC_parse != '!')
2072                     goto unknown;
2073                 RExC_parse++;
2074             case '=':           /* (?=...) */
2075             case '!':           /* (?!...) */
2076                 RExC_seen_zerolen++;
2077             case ':':           /* (?:...) */
2078             case '>':           /* (?>...) */
2079                 break;
2080             case '$':           /* (?$...) */
2081             case '@':           /* (?@...) */
2082                 vFAIL2("Sequence (?%c...) not implemented", (int)paren);
2083                 break;
2084             case '#':           /* (?#...) */
2085                 while (*RExC_parse && *RExC_parse != ')')
2086                     RExC_parse++;
2087                 if (*RExC_parse != ')')
2088                     FAIL("Sequence (?#... not terminated");
2089                 nextchar(pRExC_state);
2090                 *flagp = TRYAGAIN;
2091                 return NULL;
2092             case 'p':           /* (?p...) */
2093                 if (SIZE_ONLY && ckWARN2(WARN_DEPRECATED, WARN_REGEXP))
2094                     vWARNdep(RExC_parse, "(?p{}) is deprecated - use (??{})");
2095                 /* FALL THROUGH*/
2096             case '?':           /* (??...) */
2097                 logical = 1;
2098                 paren = *RExC_parse++;
2099                 /* FALL THROUGH */
2100             case '{':           /* (?{...}) */
2101             {
2102                 I32 count = 1, n = 0;
2103                 char c;
2104                 char *s = RExC_parse;
2105                 SV *sv;
2106                 OP_4tree *sop, *rop;
2107
2108                 RExC_seen_zerolen++;
2109                 RExC_seen |= REG_SEEN_EVAL;
2110                 while (count && (c = *RExC_parse)) {
2111                     if (c == '\\' && RExC_parse[1])
2112                         RExC_parse++;
2113                     else if (c == '{')
2114                         count++;
2115                     else if (c == '}')
2116                         count--;
2117                     RExC_parse++;
2118                 }
2119                 if (*RExC_parse != ')')
2120                 {
2121                     RExC_parse = s;
2122                     vFAIL("Sequence (?{...}) not terminated or not {}-balanced");
2123                 }
2124                 if (!SIZE_ONLY) {
2125                     AV *av;
2126
2127                     if (RExC_parse - 1 - s)
2128                         sv = newSVpvn(s, RExC_parse - 1 - s);
2129                     else
2130                         sv = newSVpvn("", 0);
2131
2132                     ENTER;
2133                     Perl_save_re_context(aTHX);
2134                     rop = sv_compile_2op(sv, &sop, "re", &av);
2135                     LEAVE;
2136
2137                     n = add_data(pRExC_state, 3, "nop");
2138                     RExC_rx->data->data[n] = (void*)rop;
2139                     RExC_rx->data->data[n+1] = (void*)sop;
2140                     RExC_rx->data->data[n+2] = (void*)av;
2141                     SvREFCNT_dec(sv);
2142                 }
2143                 else {                                          /* First pass */
2144                     if (PL_reginterp_cnt < ++RExC_seen_evals
2145                         && PL_curcop != &PL_compiling)
2146                         /* No compiled RE interpolated, has runtime
2147                            components ===> unsafe.  */
2148                         FAIL("Eval-group not allowed at runtime, use re 'eval'");
2149                     if (PL_tainting && PL_tainted)
2150                         FAIL("Eval-group in insecure regular expression");
2151                 }
2152
2153                 nextchar(pRExC_state);
2154                 if (logical) {
2155                     ret = reg_node(pRExC_state, LOGICAL);
2156                     if (!SIZE_ONLY)
2157                         ret->flags = 2;
2158                     regtail(pRExC_state, ret, reganode(pRExC_state, EVAL, n));
2159                     /* deal with the length of this later - MJD */
2160                     return ret;
2161                 }
2162                 return reganode(pRExC_state, EVAL, n);
2163             }
2164             case '(':           /* (?(?{...})...) and (?(?=...)...) */
2165             {
2166                 if (RExC_parse[0] == '?') {        /* (?(?...)) */
2167                     if (RExC_parse[1] == '=' || RExC_parse[1] == '!'
2168                         || RExC_parse[1] == '<'
2169                         || RExC_parse[1] == '{') { /* Lookahead or eval. */
2170                         I32 flag;
2171
2172                         ret = reg_node(pRExC_state, LOGICAL);
2173                         if (!SIZE_ONLY)
2174                             ret->flags = 1;
2175                         regtail(pRExC_state, ret, reg(pRExC_state, 1, &flag));
2176                         goto insert_if;
2177                     }
2178                 }
2179                 else if (RExC_parse[0] >= '1' && RExC_parse[0] <= '9' ) {
2180                     /* (?(1)...) */
2181                     parno = atoi(RExC_parse++);
2182
2183                     while (isDIGIT(*RExC_parse))
2184                         RExC_parse++;
2185                     ret = reganode(pRExC_state, GROUPP, parno);
2186
2187                     if ((c = *nextchar(pRExC_state)) != ')')
2188                         vFAIL("Switch condition not recognized");
2189                   insert_if:
2190                     regtail(pRExC_state, ret, reganode(pRExC_state, IFTHEN, 0));
2191                     br = regbranch(pRExC_state, &flags, 1);
2192                     if (br == NULL)
2193                         br = reganode(pRExC_state, LONGJMP, 0);
2194                     else
2195                         regtail(pRExC_state, br, reganode(pRExC_state, LONGJMP, 0));
2196                     c = *nextchar(pRExC_state);
2197                     if (flags&HASWIDTH)
2198                         *flagp |= HASWIDTH;
2199                     if (c == '|') {
2200                         lastbr = reganode(pRExC_state, IFTHEN, 0); /* Fake one for optimizer. */
2201                         regbranch(pRExC_state, &flags, 1);
2202                         regtail(pRExC_state, ret, lastbr);
2203                         if (flags&HASWIDTH)
2204                             *flagp |= HASWIDTH;
2205                         c = *nextchar(pRExC_state);
2206                     }
2207                     else
2208                         lastbr = NULL;
2209                     if (c != ')')
2210                         vFAIL("Switch (?(condition)... contains too many branches");
2211                     ender = reg_node(pRExC_state, TAIL);
2212                     regtail(pRExC_state, br, ender);
2213                     if (lastbr) {
2214                         regtail(pRExC_state, lastbr, ender);
2215                         regtail(pRExC_state, NEXTOPER(NEXTOPER(lastbr)), ender);
2216                     }
2217                     else
2218                         regtail(pRExC_state, ret, ender);
2219                     return ret;
2220                 }
2221                 else {
2222                     vFAIL2("Unknown switch condition (?(%.2s", RExC_parse);
2223                 }
2224             }
2225             case 0:
2226                 RExC_parse--; /* for vFAIL to print correctly */
2227                 vFAIL("Sequence (? incomplete");
2228                 break;
2229             default:
2230                 --RExC_parse;
2231               parse_flags:      /* (?i) */
2232                 while (*RExC_parse && strchr("iogcmsx", *RExC_parse)) {
2233                     /* (?g), (?gc) and (?o) are useless here
2234                        and must be globally applied -- japhy */
2235
2236                     if (*RExC_parse == 'o' || *RExC_parse == 'g') {
2237                         if (SIZE_ONLY && ckWARN(WARN_REGEXP)) {
2238                             I32 wflagbit = *RExC_parse == 'o' ? wasted_o : wasted_g;
2239                             if (! (wastedflags & wflagbit) ) {
2240                                 wastedflags |= wflagbit;
2241                                 vWARN5(
2242                                     RExC_parse + 1,
2243                                     "Useless (%s%c) - %suse /%c modifier",
2244                                     flagsp == &negflags ? "?-" : "?",
2245                                     *RExC_parse,
2246                                     flagsp == &negflags ? "don't " : "",
2247                                     *RExC_parse
2248                                 );
2249                             }
2250                         }
2251                     }
2252                     else if (*RExC_parse == 'c') {
2253                         if (SIZE_ONLY && ckWARN(WARN_REGEXP)) {
2254                             if (! (wastedflags & wasted_c) ) {
2255                                 wastedflags |= wasted_gc;
2256                                 vWARN3(
2257                                     RExC_parse + 1,
2258                                     "Useless (%sc) - %suse /gc modifier",
2259                                     flagsp == &negflags ? "?-" : "?",
2260                                     flagsp == &negflags ? "don't " : ""
2261                                 );
2262                             }
2263                         }
2264                     }
2265                     else { pmflag(flagsp, *RExC_parse); }
2266
2267                     ++RExC_parse;
2268                 }
2269                 if (*RExC_parse == '-') {
2270                     flagsp = &negflags;
2271                     wastedflags = 0;  /* reset so (?g-c) warns twice */
2272                     ++RExC_parse;
2273                     goto parse_flags;
2274                 }
2275                 RExC_flags16 |= posflags;
2276                 RExC_flags16 &= ~negflags;
2277                 if (*RExC_parse == ':') {
2278                     RExC_parse++;
2279                     paren = ':';
2280                     break;
2281                 }
2282               unknown:
2283                 if (*RExC_parse != ')') {
2284                     RExC_parse++;
2285                     vFAIL3("Sequence (%.*s...) not recognized", RExC_parse-seqstart, seqstart);
2286                 }
2287                 nextchar(pRExC_state);
2288                 *flagp = TRYAGAIN;
2289                 return NULL;
2290             }
2291         }
2292         else {                  /* (...) */
2293             parno = RExC_npar;
2294             RExC_npar++;
2295             ret = reganode(pRExC_state, OPEN, parno);
2296             Set_Node_Length(ret, 1); /* MJD */
2297             Set_Node_Offset(ret, RExC_parse); /* MJD */
2298             open = 1;
2299         }
2300     }
2301     else                        /* ! paren */
2302         ret = NULL;
2303
2304     /* Pick up the branches, linking them together. */
2305     parse_start = RExC_parse;   /* MJD */
2306     br = regbranch(pRExC_state, &flags, 1);
2307     /*     branch_len = (paren != 0); */
2308
2309     if (br == NULL)
2310         return(NULL);
2311     if (*RExC_parse == '|') {
2312         if (!SIZE_ONLY && RExC_extralen) {
2313             reginsert(pRExC_state, BRANCHJ, br);
2314         }
2315         else {                  /* MJD */
2316             reginsert(pRExC_state, BRANCH, br);
2317             Set_Node_Length(br, paren != 0);
2318             Set_Node_Offset_To_R(br-RExC_emit_start, parse_start-RExC_start);
2319         }
2320         have_branch = 1;
2321         if (SIZE_ONLY)
2322             RExC_extralen += 1;         /* For BRANCHJ-BRANCH. */
2323     }
2324     else if (paren == ':') {
2325         *flagp |= flags&SIMPLE;
2326     }
2327     if (open) {                         /* Starts with OPEN. */
2328         regtail(pRExC_state, ret, br);          /* OPEN -> first. */
2329     }
2330     else if (paren != '?')              /* Not Conditional */
2331         ret = br;
2332     if (flags&HASWIDTH)
2333         *flagp |= HASWIDTH;
2334     *flagp |= flags&SPSTART;
2335     lastbr = br;
2336     while (*RExC_parse == '|') {
2337         if (!SIZE_ONLY && RExC_extralen) {
2338             ender = reganode(pRExC_state, LONGJMP,0);
2339             regtail(pRExC_state, NEXTOPER(NEXTOPER(lastbr)), ender); /* Append to the previous. */
2340         }
2341         if (SIZE_ONLY)
2342             RExC_extralen += 2;         /* Account for LONGJMP. */
2343         nextchar(pRExC_state);
2344         br = regbranch(pRExC_state, &flags, 0);
2345
2346         if (br == NULL)
2347             return(NULL);
2348         regtail(pRExC_state, lastbr, br);               /* BRANCH -> BRANCH. */
2349         lastbr = br;
2350         if (flags&HASWIDTH)
2351             *flagp |= HASWIDTH;
2352         *flagp |= flags&SPSTART;
2353     }
2354
2355     if (have_branch || paren != ':') {
2356         /* Make a closing node, and hook it on the end. */
2357         switch (paren) {
2358         case ':':
2359             ender = reg_node(pRExC_state, TAIL);
2360             break;
2361         case 1:
2362             ender = reganode(pRExC_state, CLOSE, parno);
2363             Set_Node_Offset(ender,RExC_parse+1); /* MJD */
2364             Set_Node_Length(ender,1); /* MJD */
2365             break;
2366         case '<':
2367         case ',':
2368         case '=':
2369         case '!':
2370             *flagp &= ~HASWIDTH;
2371             /* FALL THROUGH */
2372         case '>':
2373             ender = reg_node(pRExC_state, SUCCEED);
2374             break;
2375         case 0:
2376             ender = reg_node(pRExC_state, END);
2377             break;
2378         }
2379         regtail(pRExC_state, lastbr, ender);
2380
2381         if (have_branch) {
2382             /* Hook the tails of the branches to the closing node. */
2383             for (br = ret; br != NULL; br = regnext(br)) {
2384                 regoptail(pRExC_state, br, ender);
2385             }
2386         }
2387     }
2388
2389     {
2390         char *p;
2391         static char parens[] = "=!<,>";
2392
2393         if (paren && (p = strchr(parens, paren))) {
2394             int node = ((p - parens) % 2) ? UNLESSM : IFMATCH;
2395             int flag = (p - parens) > 1;
2396
2397             if (paren == '>')
2398                 node = SUSPEND, flag = 0;
2399             reginsert(pRExC_state, node,ret);
2400             ret->flags = flag;
2401             regtail(pRExC_state, ret, reg_node(pRExC_state, TAIL));
2402         }
2403     }
2404
2405     /* Check for proper termination. */
2406     if (paren) {
2407         RExC_flags16 = oregflags;
2408         if (RExC_parse >= RExC_end || *nextchar(pRExC_state) != ')') {
2409             RExC_parse = oregcomp_parse;
2410             vFAIL("Unmatched (");
2411         }
2412     }
2413     else if (!paren && RExC_parse < RExC_end) {
2414         if (*RExC_parse == ')') {
2415             RExC_parse++;
2416             vFAIL("Unmatched )");
2417         }
2418         else
2419             FAIL("Junk on end of regexp");      /* "Can't happen". */
2420         /* NOTREACHED */
2421     }
2422
2423     return(ret);
2424 }
2425
2426 /*
2427  - regbranch - one alternative of an | operator
2428  *
2429  * Implements the concatenation operator.
2430  */
2431 STATIC regnode *
2432 S_regbranch(pTHX_ RExC_state_t *pRExC_state, I32 *flagp, I32 first)
2433 {
2434     register regnode *ret;
2435     register regnode *chain = NULL;
2436     register regnode *latest;
2437     I32 flags = 0, c = 0;
2438
2439     if (first)
2440         ret = NULL;
2441     else {
2442         if (!SIZE_ONLY && RExC_extralen)
2443             ret = reganode(pRExC_state, BRANCHJ,0);
2444         else {
2445             ret = reg_node(pRExC_state, BRANCH);
2446             Set_Node_Length(ret, 1);
2447         }
2448     }
2449
2450     if (!first && SIZE_ONLY)
2451         RExC_extralen += 1;                     /* BRANCHJ */
2452
2453     *flagp = WORST;                     /* Tentatively. */
2454
2455     RExC_parse--;
2456     nextchar(pRExC_state);
2457     while (RExC_parse < RExC_end && *RExC_parse != '|' && *RExC_parse != ')') {
2458         flags &= ~TRYAGAIN;
2459         latest = regpiece(pRExC_state, &flags);
2460         if (latest == NULL) {
2461             if (flags & TRYAGAIN)
2462                 continue;
2463             return(NULL);
2464         }
2465         else if (ret == NULL)
2466             ret = latest;
2467         *flagp |= flags&HASWIDTH;
2468         if (chain == NULL)      /* First piece. */
2469             *flagp |= flags&SPSTART;
2470         else {
2471             RExC_naughty++;
2472             regtail(pRExC_state, chain, latest);
2473         }
2474         chain = latest;
2475         c++;
2476     }
2477     if (chain == NULL) {        /* Loop ran zero times. */
2478         chain = reg_node(pRExC_state, NOTHING);
2479         if (ret == NULL)
2480             ret = chain;
2481     }
2482     if (c == 1) {
2483         *flagp |= flags&SIMPLE;
2484     }
2485
2486     return(ret);
2487 }
2488
2489 /*
2490  - regpiece - something followed by possible [*+?]
2491  *
2492  * Note that the branching code sequences used for ? and the general cases
2493  * of * and + are somewhat optimized:  they use the same NOTHING node as
2494  * both the endmarker for their branch list and the body of the last branch.
2495  * It might seem that this node could be dispensed with entirely, but the
2496  * endmarker role is not redundant.
2497  */
2498 STATIC regnode *
2499 S_regpiece(pTHX_ RExC_state_t *pRExC_state, I32 *flagp)
2500 {
2501     register regnode *ret;
2502     register char op;
2503     register char *next;
2504     I32 flags;
2505     char *origparse = RExC_parse;
2506     char *maxpos;
2507     I32 min;
2508     I32 max = REG_INFTY;
2509     char *parse_start;
2510
2511     ret = regatom(pRExC_state, &flags);
2512     if (ret == NULL) {
2513         if (flags & TRYAGAIN)
2514             *flagp |= TRYAGAIN;
2515         return(NULL);
2516     }
2517
2518     op = *RExC_parse;
2519
2520     if (op == '{' && regcurly(RExC_parse)) {
2521         parse_start = RExC_parse; /* MJD */
2522         next = RExC_parse + 1;
2523         maxpos = Nullch;
2524         while (isDIGIT(*next) || *next == ',') {
2525             if (*next == ',') {
2526                 if (maxpos)
2527                     break;
2528                 else
2529                     maxpos = next;
2530             }
2531             next++;
2532         }
2533         if (*next == '}') {             /* got one */
2534             if (!maxpos)
2535                 maxpos = next;
2536             RExC_parse++;
2537             min = atoi(RExC_parse);
2538             if (*maxpos == ',')
2539                 maxpos++;
2540             else
2541                 maxpos = RExC_parse;
2542             max = atoi(maxpos);
2543             if (!max && *maxpos != '0')
2544                 max = REG_INFTY;                /* meaning "infinity" */
2545             else if (max >= REG_INFTY)
2546                 vFAIL2("Quantifier in {,} bigger than %d", REG_INFTY - 1);
2547             RExC_parse = next;
2548             nextchar(pRExC_state);
2549
2550         do_curly:
2551             if ((flags&SIMPLE)) {
2552                 RExC_naughty += 2 + RExC_naughty / 2;
2553                 reginsert(pRExC_state, CURLY, ret);
2554                 Set_Node_Offset(ret, parse_start+1); /* MJD */
2555                 Set_Node_Cur_Length(ret);
2556             }
2557             else {
2558                 regnode *w = reg_node(pRExC_state, WHILEM);
2559
2560                 w->flags = 0;
2561                 regtail(pRExC_state, ret, w);
2562                 if (!SIZE_ONLY && RExC_extralen) {
2563                     reginsert(pRExC_state, LONGJMP,ret);
2564                     reginsert(pRExC_state, NOTHING,ret);
2565                     NEXT_OFF(ret) = 3;  /* Go over LONGJMP. */
2566                 }
2567                 reginsert(pRExC_state, CURLYX,ret);
2568                                 /* MJD hk */
2569                 Set_Node_Offset(ret, parse_start+1);
2570                 Set_Node_Length(ret,
2571                                 op == '{' ? (RExC_parse - parse_start) : 1);
2572
2573                 if (!SIZE_ONLY && RExC_extralen)
2574                     NEXT_OFF(ret) = 3;  /* Go over NOTHING to LONGJMP. */
2575                 regtail(pRExC_state, ret, reg_node(pRExC_state, NOTHING));
2576                 if (SIZE_ONLY)
2577                     RExC_whilem_seen++, RExC_extralen += 3;
2578                 RExC_naughty += 4 + RExC_naughty;       /* compound interest */
2579             }
2580             ret->flags = 0;
2581
2582             if (min > 0)
2583                 *flagp = WORST;
2584             if (max > 0)
2585                 *flagp |= HASWIDTH;
2586             if (max && max < min)
2587                 vFAIL("Can't do {n,m} with n > m");
2588             if (!SIZE_ONLY) {
2589                 ARG1_SET(ret, min);
2590                 ARG2_SET(ret, max);
2591             }
2592
2593             goto nest_check;
2594         }
2595     }
2596
2597     if (!ISMULT1(op)) {
2598         *flagp = flags;
2599         return(ret);
2600     }
2601
2602 #if 0                           /* Now runtime fix should be reliable. */
2603
2604     /* if this is reinstated, don't forget to put this back into perldiag:
2605
2606             =item Regexp *+ operand could be empty at {#} in regex m/%s/
2607
2608            (F) The part of the regexp subject to either the * or + quantifier
2609            could match an empty string. The {#} shows in the regular
2610            expression about where the problem was discovered.
2611
2612     */
2613
2614     if (!(flags&HASWIDTH) && op != '?')
2615       vFAIL("Regexp *+ operand could be empty");
2616 #endif
2617
2618     parse_start = RExC_parse;
2619     nextchar(pRExC_state);
2620
2621     *flagp = (op != '+') ? (WORST|SPSTART|HASWIDTH) : (WORST|HASWIDTH);
2622
2623     if (op == '*' && (flags&SIMPLE)) {
2624         reginsert(pRExC_state, STAR, ret);
2625         ret->flags = 0;
2626         RExC_naughty += 4;
2627     }
2628     else if (op == '*') {
2629         min = 0;
2630         goto do_curly;
2631     }
2632     else if (op == '+' && (flags&SIMPLE)) {
2633         reginsert(pRExC_state, PLUS, ret);
2634         ret->flags = 0;
2635         RExC_naughty += 3;
2636     }
2637     else if (op == '+') {
2638         min = 1;
2639         goto do_curly;
2640     }
2641     else if (op == '?') {
2642         min = 0; max = 1;
2643         goto do_curly;
2644     }
2645   nest_check:
2646     if (ckWARN(WARN_REGEXP) && !SIZE_ONLY && !(flags&HASWIDTH) && max > REG_INFTY/3) {
2647         vWARN3(RExC_parse,
2648                "%.*s matches null string many times",
2649                RExC_parse - origparse,
2650                origparse);
2651     }
2652
2653     if (*RExC_parse == '?') {
2654         nextchar(pRExC_state);
2655         reginsert(pRExC_state, MINMOD, ret);
2656         regtail(pRExC_state, ret, ret + NODE_STEP_REGNODE);
2657     }
2658     if (ISMULT2(RExC_parse)) {
2659         RExC_parse++;
2660         vFAIL("Nested quantifiers");
2661     }
2662
2663     return(ret);
2664 }
2665
2666 /*
2667  - regatom - the lowest level
2668  *
2669  * Optimization:  gobbles an entire sequence of ordinary characters so that
2670  * it can turn them into a single node, which is smaller to store and
2671  * faster to run.  Backslashed characters are exceptions, each becoming a
2672  * separate node; the code is simpler that way and it's not worth fixing.
2673  *
2674  * [Yes, it is worth fixing, some scripts can run twice the speed.] */
2675 STATIC regnode *
2676 S_regatom(pTHX_ RExC_state_t *pRExC_state, I32 *flagp)
2677 {
2678     register regnode *ret = 0;
2679     I32 flags;
2680
2681     *flagp = WORST;             /* Tentatively. */
2682
2683 tryagain:
2684     switch (*RExC_parse) {
2685     case '^':
2686         RExC_seen_zerolen++;
2687         nextchar(pRExC_state);
2688         if (RExC_flags16 & PMf_MULTILINE)
2689             ret = reg_node(pRExC_state, MBOL);
2690         else if (RExC_flags16 & PMf_SINGLELINE)
2691             ret = reg_node(pRExC_state, SBOL);
2692         else
2693             ret = reg_node(pRExC_state, BOL);
2694         Set_Node_Length(ret, 1); /* MJD */
2695         break;
2696     case '$':
2697         nextchar(pRExC_state);
2698         if (*RExC_parse)
2699             RExC_seen_zerolen++;
2700         if (RExC_flags16 & PMf_MULTILINE)
2701             ret = reg_node(pRExC_state, MEOL);
2702         else if (RExC_flags16 & PMf_SINGLELINE)
2703             ret = reg_node(pRExC_state, SEOL);
2704         else
2705             ret = reg_node(pRExC_state, EOL);
2706         Set_Node_Length(ret, 1); /* MJD */
2707         break;
2708     case '.':
2709         nextchar(pRExC_state);
2710         if (RExC_flags16 & PMf_SINGLELINE)
2711             ret = reg_node(pRExC_state, SANY);
2712         else
2713             ret = reg_node(pRExC_state, REG_ANY);
2714         *flagp |= HASWIDTH|SIMPLE;
2715         RExC_naughty++;
2716         Set_Node_Length(ret, 1); /* MJD */
2717         break;
2718     case '[':
2719     {
2720         char *oregcomp_parse = ++RExC_parse;
2721         ret = regclass(pRExC_state);
2722         if (*RExC_parse != ']') {
2723             RExC_parse = oregcomp_parse;
2724             vFAIL("Unmatched [");
2725         }
2726         nextchar(pRExC_state);
2727         *flagp |= HASWIDTH|SIMPLE;
2728         Set_Node_Length(ret, RExC_parse - oregcomp_parse + 1); /* MJD */
2729         break;
2730     }
2731     case '(':
2732         nextchar(pRExC_state);
2733         ret = reg(pRExC_state, 1, &flags);
2734         if (ret == NULL) {
2735                 if (flags & TRYAGAIN) {
2736                     if (RExC_parse == RExC_end) {
2737                          /* Make parent create an empty node if needed. */
2738                         *flagp |= TRYAGAIN;
2739                         return(NULL);
2740                     }
2741                     goto tryagain;
2742                 }
2743                 return(NULL);
2744         }
2745         *flagp |= flags&(HASWIDTH|SPSTART|SIMPLE);
2746         break;
2747     case '|':
2748     case ')':
2749         if (flags & TRYAGAIN) {
2750             *flagp |= TRYAGAIN;
2751             return NULL;
2752         }
2753         vFAIL("Internal urp");
2754                                 /* Supposed to be caught earlier. */
2755         break;
2756     case '{':
2757         if (!regcurly(RExC_parse)) {
2758             RExC_parse++;
2759             goto defchar;
2760         }
2761         /* FALL THROUGH */
2762     case '?':
2763     case '+':
2764     case '*':
2765         RExC_parse++;
2766         vFAIL("Quantifier follows nothing");
2767         break;
2768     case '\\':
2769         switch (*++RExC_parse) {
2770         case 'A':
2771             RExC_seen_zerolen++;
2772             ret = reg_node(pRExC_state, SBOL);
2773             *flagp |= SIMPLE;
2774             nextchar(pRExC_state);
2775             Set_Node_Length(ret, 2); /* MJD */
2776             break;
2777         case 'G':
2778             ret = reg_node(pRExC_state, GPOS);
2779             RExC_seen |= REG_SEEN_GPOS;
2780             *flagp |= SIMPLE;
2781             nextchar(pRExC_state);
2782             Set_Node_Length(ret, 2); /* MJD */
2783             break;
2784         case 'Z':
2785             ret = reg_node(pRExC_state, SEOL);
2786             *flagp |= SIMPLE;
2787             nextchar(pRExC_state);
2788             break;
2789         case 'z':
2790             ret = reg_node(pRExC_state, EOS);
2791             *flagp |= SIMPLE;
2792             RExC_seen_zerolen++;                /* Do not optimize RE away */
2793             nextchar(pRExC_state);
2794             Set_Node_Length(ret, 2); /* MJD */
2795             break;
2796         case 'C':
2797             ret = reg_node(pRExC_state, SANY);
2798             RExC_seen |= REG_SEEN_SANY;
2799             *flagp |= HASWIDTH|SIMPLE;
2800             nextchar(pRExC_state);
2801             Set_Node_Length(ret, 2); /* MJD */
2802             break;
2803         case 'X':
2804             ret = reg_node(pRExC_state, CLUMP);
2805             *flagp |= HASWIDTH;
2806             nextchar(pRExC_state);
2807             Set_Node_Length(ret, 2); /* MJD */
2808             break;
2809         case 'w':
2810             ret = reg_node(pRExC_state, LOC ? ALNUML     : ALNUM);
2811             *flagp |= HASWIDTH|SIMPLE;
2812             nextchar(pRExC_state);
2813             Set_Node_Length(ret, 2); /* MJD */
2814             break;
2815         case 'W':
2816             ret = reg_node(pRExC_state, LOC ? NALNUML     : NALNUM);
2817             *flagp |= HASWIDTH|SIMPLE;
2818             nextchar(pRExC_state);
2819             Set_Node_Length(ret, 2); /* MJD */
2820             break;
2821         case 'b':
2822             RExC_seen_zerolen++;
2823             RExC_seen |= REG_SEEN_LOOKBEHIND;
2824             ret = reg_node(pRExC_state, LOC ? BOUNDL     : BOUND);
2825             *flagp |= SIMPLE;
2826             nextchar(pRExC_state);
2827             Set_Node_Length(ret, 2); /* MJD */
2828             break;
2829         case 'B':
2830             RExC_seen_zerolen++;
2831             RExC_seen |= REG_SEEN_LOOKBEHIND;
2832             ret = reg_node(pRExC_state, LOC ? NBOUNDL     : NBOUND);
2833             *flagp |= SIMPLE;
2834             nextchar(pRExC_state);
2835             Set_Node_Length(ret, 2); /* MJD */
2836             break;
2837         case 's':
2838             ret = reg_node(pRExC_state, LOC ? SPACEL     : SPACE);
2839             *flagp |= HASWIDTH|SIMPLE;
2840             nextchar(pRExC_state);
2841             Set_Node_Length(ret, 2); /* MJD */
2842             break;
2843         case 'S':
2844             ret = reg_node(pRExC_state, LOC ? NSPACEL     : NSPACE);
2845             *flagp |= HASWIDTH|SIMPLE;
2846             nextchar(pRExC_state);
2847             Set_Node_Length(ret, 2); /* MJD */
2848             break;
2849         case 'd':
2850             ret = reg_node(pRExC_state, DIGIT);
2851             *flagp |= HASWIDTH|SIMPLE;
2852             nextchar(pRExC_state);
2853             Set_Node_Length(ret, 2); /* MJD */
2854             break;
2855         case 'D':
2856             ret = reg_node(pRExC_state, NDIGIT);
2857             *flagp |= HASWIDTH|SIMPLE;
2858             nextchar(pRExC_state);
2859             Set_Node_Length(ret, 2); /* MJD */
2860             break;
2861         case 'p':
2862         case 'P':
2863             {
2864                 char* oldregxend = RExC_end;
2865                 char* parse_start = RExC_parse;
2866
2867                 if (RExC_parse[1] == '{') {
2868                   /* a lovely hack--pretend we saw [\pX] instead */
2869                     RExC_end = strchr(RExC_parse, '}');
2870                     if (!RExC_end) {
2871                         RExC_parse += 2;
2872                         RExC_end = oldregxend;
2873                         vFAIL("Missing right brace on \\p{}");
2874                     }
2875                     RExC_end++;
2876                 }
2877                 else
2878                     RExC_end = RExC_parse + 2;
2879                 RExC_parse--;
2880
2881                 ret = regclass(pRExC_state);
2882
2883                 RExC_end = oldregxend;
2884                 RExC_parse--;
2885                 Set_Node_Cur_Length(ret); /* MJD */
2886                 nextchar(pRExC_state);
2887                 *flagp |= HASWIDTH|SIMPLE;
2888             }
2889             break;
2890         case 'n':
2891         case 'r':
2892         case 't':
2893         case 'f':
2894         case 'e':
2895         case 'a':
2896         case 'x':
2897         case 'c':
2898         case '0':
2899             goto defchar;
2900         case '1': case '2': case '3': case '4':
2901         case '5': case '6': case '7': case '8': case '9':
2902             {
2903                 I32 num = atoi(RExC_parse);
2904
2905                 if (num > 9 && num >= RExC_npar)
2906                     goto defchar;
2907                 else {
2908                     char * parse_start = RExC_parse - 1; /* MJD */
2909                     while (isDIGIT(*RExC_parse))
2910                         RExC_parse++;
2911
2912                     if (!SIZE_ONLY && num > RExC_rx->nparens)
2913                         vFAIL("Reference to nonexistent group");
2914                     RExC_sawback = 1;
2915                     ret = reganode(pRExC_state, FOLD
2916                                    ? (LOC ? REFFL : REFF)
2917                                    : REF, num);
2918                     *flagp |= HASWIDTH;
2919
2920                     /* override incorrect value set in reganode MJD */
2921                     Set_Node_Offset(ret, parse_start+1);
2922                     Set_Node_Cur_Length(ret); /* MJD */
2923                     RExC_parse--;
2924                     nextchar(pRExC_state);
2925                 }
2926             }
2927             break;
2928         case '\0':
2929             if (RExC_parse >= RExC_end)
2930                 FAIL("Trailing \\");
2931             /* FALL THROUGH */
2932         default:
2933             /* Do not generate `unrecognized' warnings here, we fall
2934                back into the quick-grab loop below */
2935             goto defchar;
2936         }
2937         break;
2938
2939     case '#':
2940         if (RExC_flags16 & PMf_EXTENDED) {
2941             while (RExC_parse < RExC_end && *RExC_parse != '\n') RExC_parse++;
2942             if (RExC_parse < RExC_end)
2943                 goto tryagain;
2944         }
2945         /* FALL THROUGH */
2946
2947     default: {
2948             register STRLEN len;
2949             register UV ender;
2950             register char *p;
2951             char *oldp, *s;
2952             STRLEN numlen;
2953             char *parse_start = RExC_parse - 1;
2954
2955             RExC_parse++;
2956
2957         defchar:
2958             ret = reg_node(pRExC_state, FOLD
2959                           ? (LOC ? EXACTFL : EXACTF)
2960                           : EXACT);
2961             s = STRING(ret);
2962             for (len = 0, p = RExC_parse - 1;
2963               len < 127 && p < RExC_end;
2964               len++)
2965             {
2966                 oldp = p;
2967
2968                 if (RExC_flags16 & PMf_EXTENDED)
2969                     p = regwhite(p, RExC_end);
2970                 switch (*p) {
2971                 case '^':
2972                 case '$':
2973                 case '.':
2974                 case '[':
2975                 case '(':
2976                 case ')':
2977                 case '|':
2978                     goto loopdone;
2979                 case '\\':
2980                     switch (*++p) {
2981                     case 'A':
2982                     case 'G':
2983                     case 'Z':
2984                     case 'z':
2985                     case 'w':
2986                     case 'W':
2987                     case 'b':
2988                     case 'B':
2989                     case 's':
2990                     case 'S':
2991                     case 'd':
2992                     case 'D':
2993                     case 'p':
2994                     case 'P':
2995                         --p;
2996                         goto loopdone;
2997                     case 'n':
2998                         ender = '\n';
2999                         p++;
3000                         break;
3001                     case 'r':
3002                         ender = '\r';
3003                         p++;
3004                         break;
3005                     case 't':
3006                         ender = '\t';
3007                         p++;
3008                         break;
3009                     case 'f':
3010                         ender = '\f';
3011                         p++;
3012                         break;
3013                     case 'e':
3014                           ender = ASCII_TO_NATIVE('\033');
3015                         p++;
3016                         break;
3017                     case 'a':
3018                           ender = ASCII_TO_NATIVE('\007');
3019                         p++;
3020                         break;
3021                     case 'x':
3022                         if (*++p == '{') {
3023                             char* e = strchr(p, '}');
3024
3025                             if (!e) {
3026                                 RExC_parse = p + 1;
3027                                 vFAIL("Missing right brace on \\x{}");
3028                             }
3029                             else {
3030                                 numlen = 1;     /* allow underscores */
3031                                 ender = (UV)scan_hex(p + 1, e - p - 1, &numlen);
3032                                 if (ender > 0xff)
3033                                     RExC_utf8 = 1;
3034                                 /* numlen is generous */
3035                                 if (numlen + len >= 127) {
3036                                     p--;
3037                                     goto loopdone;
3038                                 }
3039                                 p = e + 1;
3040                             }
3041                         }
3042                         else {
3043                             numlen = 0;         /* disallow underscores */
3044                             ender = (UV)scan_hex(p, 2, &numlen);
3045                             p += numlen;
3046                         }
3047                         break;
3048                     case 'c':
3049                         p++;
3050                         ender = UCHARAT(p++);
3051                         ender = toCTRL(ender);
3052                         break;
3053                     case '0': case '1': case '2': case '3':case '4':
3054                     case '5': case '6': case '7': case '8':case '9':
3055                         if (*p == '0' ||
3056                           (isDIGIT(p[1]) && atoi(p) >= RExC_npar) ) {
3057                             numlen = 0;         /* disallow underscores */
3058                             ender = (UV)scan_oct(p, 3, &numlen);
3059                             p += numlen;
3060                         }
3061                         else {
3062                             --p;
3063                             goto loopdone;
3064                         }
3065                         break;
3066                     case '\0':
3067                         if (p >= RExC_end)
3068                             FAIL("Trailing \\");
3069                         /* FALL THROUGH */
3070                     default:
3071                         if (!SIZE_ONLY && ckWARN(WARN_REGEXP) && isALPHA(*p))
3072                             vWARN2(p +1, "Unrecognized escape \\%c passed through", *p);
3073                         goto normal_default;
3074                     }
3075                     break;
3076                 default:
3077                   normal_default:
3078                     if (UTF8_IS_START(*p) && UTF) {
3079                         ender = utf8n_to_uvchr((U8*)p, RExC_end - p,
3080                                                &numlen, 0);
3081                         p += numlen;
3082                     }
3083                     else
3084                         ender = *p++;
3085                     break;
3086                 }
3087                 if (RExC_flags16 & PMf_EXTENDED)
3088                     p = regwhite(p, RExC_end);
3089                 if (UTF && FOLD) {
3090                     if (LOC)
3091                         ender = toLOWER_LC_uvchr(ender);
3092                     else
3093                         ender = toLOWER_uni(ender);
3094                 }
3095                 if (ISMULT2(p)) { /* Back off on ?+*. */
3096                     if (len)
3097                         p = oldp;
3098                     else if (!UNI_IS_INVARIANT(NATIVE_TO_UNI(ender)) && UTF) {
3099                         reguni(pRExC_state, ender, s, &numlen);
3100                         s += numlen;
3101                         len += numlen;
3102                     }
3103                     else {
3104                         len++;
3105                         REGC(ender, s++);
3106                     }
3107                     break;
3108                 }
3109                 if (!UNI_IS_INVARIANT(NATIVE_TO_UNI(ender)) && UTF) {
3110                     reguni(pRExC_state, ender, s, &numlen);
3111                     s += numlen;
3112                     len += numlen - 1;
3113                 }
3114                 else
3115                     REGC(ender, s++);
3116             }
3117         loopdone:
3118             RExC_parse = p - 1;
3119             Set_Node_Cur_Length(ret); /* MJD */
3120             nextchar(pRExC_state);
3121             {
3122                 /* len is STRLEN which is unsigned, need to copy to signed */
3123                 IV iv = len;
3124                 if (iv < 0)
3125                     vFAIL("Internal disaster");
3126             }
3127             if (len > 0)
3128                 *flagp |= HASWIDTH;
3129             if (len == 1)
3130                 *flagp |= SIMPLE;
3131             if (!SIZE_ONLY)
3132                 STR_LEN(ret) = len;
3133             if (SIZE_ONLY)
3134                 RExC_size += STR_SZ(len);
3135             else
3136                 RExC_emit += STR_SZ(len);
3137         }
3138         break;
3139     }
3140
3141     return(ret);
3142 }
3143
3144 STATIC char *
3145 S_regwhite(pTHX_ char *p, char *e)
3146 {
3147     while (p < e) {
3148         if (isSPACE(*p))
3149             ++p;
3150         else if (*p == '#') {
3151             do {
3152                 p++;
3153             } while (p < e && *p != '\n');
3154         }
3155         else
3156             break;
3157     }
3158     return p;
3159 }
3160
3161 /* Parse POSIX character classes: [[:foo:]], [[=foo=]], [[.foo.]].
3162    Character classes ([:foo:]) can also be negated ([:^foo:]).
3163    Returns a named class id (ANYOF_XXX) if successful, -1 otherwise.
3164    Equivalence classes ([=foo=]) and composites ([.foo.]) are parsed,
3165    but trigger warnings because they are currently unimplemented. */
3166 STATIC I32
3167 S_regpposixcc(pTHX_ RExC_state_t *pRExC_state, I32 value)
3168 {
3169     char *posixcc = 0;
3170     I32 namedclass = OOB_NAMEDCLASS;
3171
3172     if (value == '[' && RExC_parse + 1 < RExC_end &&
3173         /* I smell either [: or [= or [. -- POSIX has been here, right? */
3174         (*RExC_parse == ':' ||
3175          *RExC_parse == '=' ||
3176          *RExC_parse == '.')) {
3177         char  c = *RExC_parse;
3178         char* s = RExC_parse++;
3179
3180         while (RExC_parse < RExC_end && *RExC_parse != c)
3181             RExC_parse++;
3182         if (RExC_parse == RExC_end)
3183             /* Grandfather lone [:, [=, [. */
3184             RExC_parse = s;
3185         else {
3186             char* t = RExC_parse++; /* skip over the c */
3187
3188             if (*RExC_parse == ']') {
3189                 RExC_parse++; /* skip over the ending ] */
3190                 posixcc = s + 1;
3191                 if (*s == ':') {
3192                     I32 complement = *posixcc == '^' ? *posixcc++ : 0;
3193                     I32 skip = 5; /* the most common skip */
3194
3195                     switch (*posixcc) {
3196                     case 'a':
3197                         if (strnEQ(posixcc, "alnum", 5))
3198                             namedclass =
3199                                 complement ? ANYOF_NALNUMC : ANYOF_ALNUMC;
3200                         else if (strnEQ(posixcc, "alpha", 5))
3201                             namedclass =
3202                                 complement ? ANYOF_NALPHA : ANYOF_ALPHA;
3203                         else if (strnEQ(posixcc, "ascii", 5))
3204                             namedclass =
3205                                 complement ? ANYOF_NASCII : ANYOF_ASCII;
3206                         break;
3207                     case 'b':
3208                         if (strnEQ(posixcc, "blank", 5))
3209                             namedclass =
3210                                 complement ? ANYOF_NBLANK : ANYOF_BLANK;
3211                         break;
3212                     case 'c':
3213                         if (strnEQ(posixcc, "cntrl", 5))
3214                             namedclass =
3215                                 complement ? ANYOF_NCNTRL : ANYOF_CNTRL;
3216                         break;
3217                     case 'd':
3218                         if (strnEQ(posixcc, "digit", 5))
3219                             namedclass =
3220                                 complement ? ANYOF_NDIGIT : ANYOF_DIGIT;
3221                         break;
3222                     case 'g':
3223                         if (strnEQ(posixcc, "graph", 5))
3224                             namedclass =
3225                                 complement ? ANYOF_NGRAPH : ANYOF_GRAPH;
3226                         break;
3227                     case 'l':
3228                         if (strnEQ(posixcc, "lower", 5))
3229                             namedclass =
3230                                 complement ? ANYOF_NLOWER : ANYOF_LOWER;
3231                         break;
3232                     case 'p':
3233                         if (strnEQ(posixcc, "print", 5))
3234                             namedclass =
3235                                 complement ? ANYOF_NPRINT : ANYOF_PRINT;
3236                         else if (strnEQ(posixcc, "punct", 5))
3237                             namedclass =
3238                                 complement ? ANYOF_NPUNCT : ANYOF_PUNCT;
3239                         break;
3240                     case 's':
3241                         if (strnEQ(posixcc, "space", 5))
3242                             namedclass =
3243                                 complement ? ANYOF_NPSXSPC : ANYOF_PSXSPC;
3244                         break;
3245                     case 'u':
3246                         if (strnEQ(posixcc, "upper", 5))
3247                             namedclass =
3248                                 complement ? ANYOF_NUPPER : ANYOF_UPPER;
3249                         break;
3250                     case 'w': /* this is not POSIX, this is the Perl \w */
3251                         if (strnEQ(posixcc, "word", 4)) {
3252                             namedclass =
3253                                 complement ? ANYOF_NALNUM : ANYOF_ALNUM;
3254                             skip = 4;
3255                         }
3256                         break;
3257                     case 'x':
3258                         if (strnEQ(posixcc, "xdigit", 6)) {
3259                             namedclass =
3260                                 complement ? ANYOF_NXDIGIT : ANYOF_XDIGIT;
3261                             skip = 6;
3262                         }
3263                         break;
3264                     }
3265                     if (namedclass == OOB_NAMEDCLASS ||
3266                         posixcc[skip] != ':' ||
3267                         posixcc[skip+1] != ']')
3268                     {
3269                         Simple_vFAIL3("POSIX class [:%.*s:] unknown",
3270                                       t - s - 1, s + 1);
3271                     }
3272                 } else if (!SIZE_ONLY) {
3273                     /* [[=foo=]] and [[.foo.]] are still future. */
3274
3275                     /* adjust RExC_parse so the warning shows after
3276                        the class closes */
3277                     while (*RExC_parse && *RExC_parse != ']')
3278                         RExC_parse++;
3279                     Simple_vFAIL3("POSIX syntax [%c %c] is reserved for future extensions", c, c);
3280                 }
3281             } else {
3282                 /* Maternal grandfather:
3283                  * "[:" ending in ":" but not in ":]" */
3284                 RExC_parse = s;
3285             }
3286         }
3287     }
3288
3289     return namedclass;
3290 }
3291
3292 STATIC void
3293 S_checkposixcc(pTHX_ RExC_state_t *pRExC_state)
3294 {
3295     if (!SIZE_ONLY && ckWARN(WARN_REGEXP) &&
3296         (*RExC_parse == ':' ||
3297          *RExC_parse == '=' ||
3298          *RExC_parse == '.')) {
3299         char *s = RExC_parse;
3300         char  c = *s++;
3301
3302         while(*s && isALNUM(*s))
3303             s++;
3304         if (*s && c == *s && s[1] == ']') {
3305             vWARN3(s+2, "POSIX syntax [%c %c] belongs inside character classes", c, c);
3306
3307             /* [[=foo=]] and [[.foo.]] are still future. */
3308             if (c == '=' || c == '.')
3309             {
3310                 /* adjust RExC_parse so the error shows after
3311                    the class closes */
3312                 while (*RExC_parse && *RExC_parse++ != ']')
3313                     ;
3314                 Simple_vFAIL3("POSIX syntax [%c %c] is reserved for future extensions", c, c);
3315             }
3316         }
3317     }
3318 }
3319
3320 STATIC regnode *
3321 S_regclass(pTHX_ RExC_state_t *pRExC_state)
3322 {
3323     register UV value;
3324     register IV prevvalue = OOB_UNICODE;
3325     register IV range = 0;
3326     register regnode *ret;
3327     STRLEN numlen;
3328     IV namedclass;
3329     char *rangebegin = 0;
3330     bool need_class = 0;
3331     SV *listsv = Nullsv;
3332     register char *e;
3333     UV n;
3334     bool optimize_invert = TRUE;
3335
3336     ret = reganode(pRExC_state, ANYOF, 0);
3337
3338     if (!SIZE_ONLY)
3339         ANYOF_FLAGS(ret) = 0;
3340
3341     if (*RExC_parse == '^') {   /* Complement of range. */
3342         RExC_naughty++;
3343         RExC_parse++;
3344         if (!SIZE_ONLY)
3345             ANYOF_FLAGS(ret) |= ANYOF_INVERT;
3346     }
3347
3348     if (SIZE_ONLY)
3349         RExC_size += ANYOF_SKIP;
3350     else {
3351         RExC_emit += ANYOF_SKIP;
3352         if (FOLD)
3353             ANYOF_FLAGS(ret) |= ANYOF_FOLD;
3354         if (LOC)
3355             ANYOF_FLAGS(ret) |= ANYOF_LOCALE;
3356         ANYOF_BITMAP_ZERO(ret);
3357         listsv = newSVpvn("# comment\n", 10);
3358     }
3359
3360     if (!SIZE_ONLY && ckWARN(WARN_REGEXP))
3361         checkposixcc(pRExC_state);
3362
3363     if (*RExC_parse == ']' || *RExC_parse == '-')
3364         goto charclassloop;             /* allow 1st char to be ] or - */
3365
3366     while (RExC_parse < RExC_end && *RExC_parse != ']') {
3367
3368     charclassloop:
3369
3370         namedclass = OOB_NAMEDCLASS; /* initialize as illegal */
3371
3372         if (!range)
3373             rangebegin = RExC_parse;
3374         if (UTF) {
3375             value = utf8n_to_uvchr((U8*)RExC_parse,
3376                                    RExC_end - RExC_parse,
3377                                    &numlen, 0);
3378             RExC_parse += numlen;
3379         }
3380         else
3381             value = UCHARAT(RExC_parse++);
3382         if (value == '[')
3383             namedclass = regpposixcc(pRExC_state, value);
3384         else if (value == '\\') {
3385             if (UTF) {
3386                 value = utf8n_to_uvchr((U8*)RExC_parse,
3387                                    RExC_end - RExC_parse,
3388                                    &numlen, 0);
3389                 RExC_parse += numlen;
3390             }
3391             else
3392                 value = UCHARAT(RExC_parse++);
3393             /* Some compilers cannot handle switching on 64-bit integer
3394              * values, therefore value cannot be an UV.  Yes, this will
3395              * be a problem later if we want switch on Unicode.
3396              * A similar issue a little bit later when switching on
3397              * namedclass. --jhi */
3398             switch ((I32)value) {
3399             case 'w':   namedclass = ANYOF_ALNUM;       break;
3400             case 'W':   namedclass = ANYOF_NALNUM;      break;
3401             case 's':   namedclass = ANYOF_SPACE;       break;
3402             case 'S':   namedclass = ANYOF_NSPACE;      break;
3403             case 'd':   namedclass = ANYOF_DIGIT;       break;
3404             case 'D':   namedclass = ANYOF_NDIGIT;      break;
3405             case 'p':
3406             case 'P':
3407                 if (*RExC_parse == '{') {
3408                     e = strchr(RExC_parse++, '}');
3409                     if (!e)
3410                         vFAIL("Missing right brace on \\p{}");
3411                     n = e - RExC_parse;
3412                 }
3413                 else {
3414                     e = RExC_parse;
3415                     n = 1;
3416                 }
3417                 if (!SIZE_ONLY) {
3418                     if (value == 'p')
3419                         Perl_sv_catpvf(aTHX_ listsv,
3420                                        "+utf8::%.*s\n", (int)n, RExC_parse);
3421                     else
3422                         Perl_sv_catpvf(aTHX_ listsv,
3423                                        "!utf8::%.*s\n", (int)n, RExC_parse);
3424                 }
3425                 RExC_parse = e + 1;
3426                 ANYOF_FLAGS(ret) |= ANYOF_UNICODE;
3427                 continue;
3428             case 'n':   value = '\n';                   break;
3429             case 'r':   value = '\r';                   break;
3430             case 't':   value = '\t';                   break;
3431             case 'f':   value = '\f';                   break;
3432             case 'b':   value = '\b';                   break;
3433             case 'e':   value = ASCII_TO_NATIVE('\033');break;
3434             case 'a':   value = ASCII_TO_NATIVE('\007');break;
3435             case 'x':
3436                 if (*RExC_parse == '{') {
3437                     e = strchr(RExC_parse++, '}');
3438                     if (!e)
3439                         vFAIL("Missing right brace on \\x{}");
3440                     numlen = 1;         /* allow underscores */
3441                     value = (UV)scan_hex(RExC_parse,
3442                                          e - RExC_parse,
3443                                          &numlen);
3444                     RExC_parse = e + 1;
3445                 }
3446                 else {
3447                     numlen = 0;         /* disallow underscores */
3448                     value = (UV)scan_hex(RExC_parse, 2, &numlen);
3449                     RExC_parse += numlen;
3450                 }
3451                 break;
3452             case 'c':
3453                 value = UCHARAT(RExC_parse++);
3454                 value = toCTRL(value);
3455                 break;
3456             case '0': case '1': case '2': case '3': case '4':
3457             case '5': case '6': case '7': case '8': case '9':
3458                 numlen = 0;             /* disallow underscores */
3459                 value = (UV)scan_oct(--RExC_parse, 3, &numlen);
3460                 RExC_parse += numlen;
3461                 break;
3462             default:
3463                 if (!SIZE_ONLY && ckWARN(WARN_REGEXP) && isALPHA(value))
3464                     vWARN2(RExC_parse,
3465                            "Unrecognized escape \\%c in character class passed through",
3466                            (int)value);
3467                 break;
3468             }
3469         } /* end of \blah */
3470
3471         if (namedclass > OOB_NAMEDCLASS) { /* this is a named class \blah */
3472
3473             if (!SIZE_ONLY && !need_class)
3474                 ANYOF_CLASS_ZERO(ret);
3475
3476             need_class = 1;
3477
3478             /* a bad range like a-\d, a-[:digit:] ? */
3479             if (range) {
3480                 if (!SIZE_ONLY) {
3481                     if (ckWARN(WARN_REGEXP))
3482                         vWARN4(RExC_parse,
3483                                "False [] range \"%*.*s\"",
3484                                RExC_parse - rangebegin,
3485                                RExC_parse - rangebegin,
3486                                rangebegin);
3487                     if (prevvalue < 256) {
3488                         ANYOF_BITMAP_SET(ret, prevvalue);
3489                         ANYOF_BITMAP_SET(ret, '-');
3490                     }
3491                     else {
3492                         ANYOF_FLAGS(ret) |= ANYOF_UNICODE;
3493                         Perl_sv_catpvf(aTHX_ listsv,
3494                                        "%04"UVxf"\n%04"UVxf"\n", (UV)prevvalue, (UV) '-');
3495                     }
3496                 }
3497
3498                 range = 0; /* this was not a true range */
3499             }
3500
3501             if (!SIZE_ONLY) {
3502                 if (namedclass > OOB_NAMEDCLASS)
3503                     optimize_invert = FALSE;
3504                 /* Possible truncation here but in some 64-bit environments
3505                  * the compiler gets heartburn about switch on 64-bit values.
3506                  * A similar issue a little earlier when switching on value.
3507                  * --jhi */
3508                 switch ((I32)namedclass) {
3509                 case ANYOF_ALNUM:
3510                     if (LOC)
3511                         ANYOF_CLASS_SET(ret, ANYOF_ALNUM);
3512                     else {
3513                         for (value = 0; value < 256; value++)
3514                             if (isALNUM(value))
3515                                 ANYOF_BITMAP_SET(ret, value);
3516                     }
3517                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsWord\n");
3518                     break;
3519                 case ANYOF_NALNUM:
3520                     if (LOC)
3521                         ANYOF_CLASS_SET(ret, ANYOF_NALNUM);
3522                     else {
3523                         for (value = 0; value < 256; value++)
3524                             if (!isALNUM(value))
3525                                 ANYOF_BITMAP_SET(ret, value);
3526                     }
3527                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsWord\n");
3528                     break;
3529                 case ANYOF_ALNUMC:
3530                     if (LOC)
3531                         ANYOF_CLASS_SET(ret, ANYOF_ALNUMC);
3532                     else {
3533                         for (value = 0; value < 256; value++)
3534                             if (isALNUMC(value))
3535                                 ANYOF_BITMAP_SET(ret, value);
3536                     }
3537                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsAlnum\n");
3538                     break;
3539                 case ANYOF_NALNUMC:
3540                     if (LOC)
3541                         ANYOF_CLASS_SET(ret, ANYOF_NALNUMC);
3542                     else {
3543                         for (value = 0; value < 256; value++)
3544                             if (!isALNUMC(value))
3545                                 ANYOF_BITMAP_SET(ret, value);
3546                     }
3547                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsAlnum\n");
3548                     break;
3549                 case ANYOF_ALPHA:
3550                     if (LOC)
3551                         ANYOF_CLASS_SET(ret, ANYOF_ALPHA);
3552                     else {
3553                         for (value = 0; value < 256; value++)
3554                             if (isALPHA(value))
3555                                 ANYOF_BITMAP_SET(ret, value);
3556                     }
3557                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsAlpha\n");
3558                     break;
3559                 case ANYOF_NALPHA:
3560                     if (LOC)
3561                         ANYOF_CLASS_SET(ret, ANYOF_NALPHA);
3562                     else {
3563                         for (value = 0; value < 256; value++)
3564                             if (!isALPHA(value))
3565                                 ANYOF_BITMAP_SET(ret, value);
3566                     }
3567                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsAlpha\n");
3568                     break;
3569                 case ANYOF_ASCII:
3570                     if (LOC)
3571                         ANYOF_CLASS_SET(ret, ANYOF_ASCII);
3572                     else {
3573 #ifndef EBCDIC
3574                         for (value = 0; value < 128; value++)
3575                             ANYOF_BITMAP_SET(ret, value);
3576 #else  /* EBCDIC */
3577                         for (value = 0; value < 256; value++) {
3578                             if (isASCII(value))
3579                                 ANYOF_BITMAP_SET(ret, value);
3580                         }
3581 #endif /* EBCDIC */
3582                     }
3583                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsASCII\n");
3584                     break;
3585                 case ANYOF_NASCII:
3586                     if (LOC)
3587                         ANYOF_CLASS_SET(ret, ANYOF_NASCII);
3588                     else {
3589 #ifndef EBCDIC
3590                         for (value = 128; value < 256; value++)
3591                             ANYOF_BITMAP_SET(ret, value);
3592 #else  /* EBCDIC */
3593                         for (value = 0; value < 256; value++) {
3594                             if (!isASCII(value))
3595                                 ANYOF_BITMAP_SET(ret, value);
3596                         }
3597 #endif /* EBCDIC */
3598                     }
3599                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsASCII\n");
3600                     break;
3601                 case ANYOF_BLANK:
3602                     if (LOC)
3603                         ANYOF_CLASS_SET(ret, ANYOF_BLANK);
3604                     else {
3605                         for (value = 0; value < 256; value++)
3606                             if (isBLANK(value))
3607                                 ANYOF_BITMAP_SET(ret, value);
3608                     }
3609                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsBlank\n");
3610                     break;
3611                 case ANYOF_NBLANK:
3612                     if (LOC)
3613                         ANYOF_CLASS_SET(ret, ANYOF_NBLANK);
3614                     else {
3615                         for (value = 0; value < 256; value++)
3616                             if (!isBLANK(value))
3617                                 ANYOF_BITMAP_SET(ret, value);
3618                     }
3619                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsBlank\n");
3620                     break;
3621                 case ANYOF_CNTRL:
3622                     if (LOC)
3623                         ANYOF_CLASS_SET(ret, ANYOF_CNTRL);
3624                     else {
3625                         for (value = 0; value < 256; value++)
3626                             if (isCNTRL(value))
3627                                 ANYOF_BITMAP_SET(ret, value);
3628                     }
3629                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsCntrl\n");
3630                     break;
3631                 case ANYOF_NCNTRL:
3632                     if (LOC)
3633                         ANYOF_CLASS_SET(ret, ANYOF_NCNTRL);
3634                     else {
3635                         for (value = 0; value < 256; value++)
3636                             if (!isCNTRL(value))
3637                                 ANYOF_BITMAP_SET(ret, value);
3638                     }
3639                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsCntrl\n");
3640                     break;
3641                 case ANYOF_DIGIT:
3642                     if (LOC)
3643                         ANYOF_CLASS_SET(ret, ANYOF_DIGIT);
3644                     else {
3645                         /* consecutive digits assumed */
3646                         for (value = '0'; value <= '9'; value++)
3647                             ANYOF_BITMAP_SET(ret, value);
3648                     }
3649                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsDigit\n");
3650                     break;
3651                 case ANYOF_NDIGIT:
3652                     if (LOC)
3653                         ANYOF_CLASS_SET(ret, ANYOF_NDIGIT);
3654                     else {
3655                         /* consecutive digits assumed */
3656                         for (value = 0; value < '0'; value++)
3657                             ANYOF_BITMAP_SET(ret, value);
3658                         for (value = '9' + 1; value < 256; value++)
3659                             ANYOF_BITMAP_SET(ret, value);
3660                     }
3661                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsDigit\n");
3662                     break;
3663                 case ANYOF_GRAPH:
3664                     if (LOC)
3665                         ANYOF_CLASS_SET(ret, ANYOF_GRAPH);
3666                     else {
3667                         for (value = 0; value < 256; value++)
3668                             if (isGRAPH(value))
3669                                 ANYOF_BITMAP_SET(ret, value);
3670                     }
3671                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsGraph\n");
3672                     break;
3673                 case ANYOF_NGRAPH:
3674                     if (LOC)
3675                         ANYOF_CLASS_SET(ret, ANYOF_NGRAPH);
3676                     else {
3677                         for (value = 0; value < 256; value++)
3678                             if (!isGRAPH(value))
3679                                 ANYOF_BITMAP_SET(ret, value);
3680                     }
3681                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsGraph\n");
3682                     break;
3683                 case ANYOF_LOWER:
3684                     if (LOC)
3685                         ANYOF_CLASS_SET(ret, ANYOF_LOWER);
3686                     else {
3687                         for (value = 0; value < 256; value++)
3688                             if (isLOWER(value))
3689                                 ANYOF_BITMAP_SET(ret, value);
3690                     }
3691                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsLower\n");
3692                     break;
3693                 case ANYOF_NLOWER:
3694                     if (LOC)
3695                         ANYOF_CLASS_SET(ret, ANYOF_NLOWER);
3696                     else {
3697                         for (value = 0; value < 256; value++)
3698                             if (!isLOWER(value))
3699                                 ANYOF_BITMAP_SET(ret, value);
3700                     }
3701                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsLower\n");
3702                     break;
3703                 case ANYOF_PRINT:
3704                     if (LOC)
3705                         ANYOF_CLASS_SET(ret, ANYOF_PRINT);
3706                     else {
3707                         for (value = 0; value < 256; value++)
3708                             if (isPRINT(value))
3709                                 ANYOF_BITMAP_SET(ret, value);
3710                     }
3711                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsPrint\n");
3712                     break;
3713                 case ANYOF_NPRINT:
3714                     if (LOC)
3715                         ANYOF_CLASS_SET(ret, ANYOF_NPRINT);
3716                     else {
3717                         for (value = 0; value < 256; value++)
3718                             if (!isPRINT(value))
3719                                 ANYOF_BITMAP_SET(ret, value);
3720                     }
3721                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsPrint\n");
3722                     break;
3723                 case ANYOF_PSXSPC:
3724                     if (LOC)
3725                         ANYOF_CLASS_SET(ret, ANYOF_PSXSPC);
3726                     else {
3727                         for (value = 0; value < 256; value++)
3728                             if (isPSXSPC(value))
3729                                 ANYOF_BITMAP_SET(ret, value);
3730                     }
3731                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsSpace\n");
3732                     break;
3733                 case ANYOF_NPSXSPC:
3734                     if (LOC)
3735                         ANYOF_CLASS_SET(ret, ANYOF_NPSXSPC);
3736                     else {
3737                         for (value = 0; value < 256; value++)
3738                             if (!isPSXSPC(value))
3739                                 ANYOF_BITMAP_SET(ret, value);
3740                     }
3741                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsSpace\n");
3742                     break;
3743                 case ANYOF_PUNCT:
3744                     if (LOC)
3745                         ANYOF_CLASS_SET(ret, ANYOF_PUNCT);
3746                     else {
3747                         for (value = 0; value < 256; value++)
3748                             if (isPUNCT(value))
3749                                 ANYOF_BITMAP_SET(ret, value);
3750                     }
3751                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsPunct\n");
3752                     break;
3753                 case ANYOF_NPUNCT:
3754                     if (LOC)
3755                         ANYOF_CLASS_SET(ret, ANYOF_NPUNCT);
3756                     else {
3757                         for (value = 0; value < 256; value++)
3758                             if (!isPUNCT(value))
3759                                 ANYOF_BITMAP_SET(ret, value);
3760                     }
3761                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsPunct\n");
3762                     break;
3763                 case ANYOF_SPACE:
3764                     if (LOC)
3765                         ANYOF_CLASS_SET(ret, ANYOF_SPACE);
3766                     else {
3767                         for (value = 0; value < 256; value++)
3768                             if (isSPACE(value))
3769                                 ANYOF_BITMAP_SET(ret, value);
3770                     }
3771                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsSpacePerl\n");
3772                     break;
3773                 case ANYOF_NSPACE:
3774                     if (LOC)
3775                         ANYOF_CLASS_SET(ret, ANYOF_NSPACE);
3776                     else {
3777                         for (value = 0; value < 256; value++)
3778                             if (!isSPACE(value))
3779                                 ANYOF_BITMAP_SET(ret, value);
3780                     }
3781                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsSpacePerl\n");
3782                     break;
3783                 case ANYOF_UPPER:
3784                     if (LOC)
3785                         ANYOF_CLASS_SET(ret, ANYOF_UPPER);
3786                     else {
3787                         for (value = 0; value < 256; value++)
3788                             if (isUPPER(value))
3789                                 ANYOF_BITMAP_SET(ret, value);
3790                     }
3791                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsUpper\n");
3792                     break;
3793                 case ANYOF_NUPPER:
3794                     if (LOC)
3795                         ANYOF_CLASS_SET(ret, ANYOF_NUPPER);
3796                     else {
3797                         for (value = 0; value < 256; value++)
3798                             if (!isUPPER(value))
3799                                 ANYOF_BITMAP_SET(ret, value);
3800                     }
3801                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsUpper\n");
3802                     break;
3803                 case ANYOF_XDIGIT:
3804                     if (LOC)
3805                         ANYOF_CLASS_SET(ret, ANYOF_XDIGIT);
3806                     else {
3807                         for (value = 0; value < 256; value++)
3808                             if (isXDIGIT(value))
3809                                 ANYOF_BITMAP_SET(ret, value);
3810                     }
3811                     Perl_sv_catpvf(aTHX_ listsv, "+utf8::IsXDigit\n");
3812                     break;
3813                 case ANYOF_NXDIGIT:
3814                     if (LOC)
3815                         ANYOF_CLASS_SET(ret, ANYOF_NXDIGIT);
3816                     else {
3817                         for (value = 0; value < 256; value++)
3818                             if (!isXDIGIT(value))
3819                                 ANYOF_BITMAP_SET(ret, value);
3820                     }
3821                     Perl_sv_catpvf(aTHX_ listsv, "!utf8::IsXDigit\n");
3822                     break;
3823                 default:
3824                     vFAIL("Invalid [::] class");
3825                     break;
3826                 }
3827                 if (LOC)
3828                     ANYOF_FLAGS(ret) |= ANYOF_CLASS;
3829                 continue;
3830             }
3831         } /* end of namedclass \blah */
3832
3833         if (range) {
3834             if (prevvalue > value) /* b-a */ {
3835                 Simple_vFAIL4("Invalid [] range \"%*.*s\"",
3836                               RExC_parse - rangebegin,
3837                               RExC_parse - rangebegin,
3838                               rangebegin);
3839                 range = 0; /* not a valid range */
3840             }
3841         }
3842         else {
3843             prevvalue = value; /* save the beginning of the range */
3844             if (*RExC_parse == '-' && RExC_parse+1 < RExC_end &&
3845                 RExC_parse[1] != ']') {
3846                 RExC_parse++;
3847
3848                 /* a bad range like \w-, [:word:]- ? */
3849                 if (namedclass > OOB_NAMEDCLASS) {
3850                     if (ckWARN(WARN_REGEXP))
3851                         vWARN4(RExC_parse,
3852                                "False [] range \"%*.*s\"",
3853                                RExC_parse - rangebegin,
3854                                RExC_parse - rangebegin,
3855                                rangebegin);
3856                     if (!SIZE_ONLY)
3857                         ANYOF_BITMAP_SET(ret, '-');
3858                 } else
3859                     range = 1;  /* yeah, it's a range! */
3860                 continue;       /* but do it the next time */
3861             }
3862         }
3863
3864         /* now is the next time */
3865         if (!SIZE_ONLY) {
3866             IV i;
3867
3868             if (prevvalue < 256) {
3869                 IV ceilvalue = value < 256 ? value : 255;
3870
3871 #ifdef EBCDIC
3872                 if ((isLOWER(prevvalue) && isLOWER(ceilvalue)) ||
3873                     (isUPPER(prevvalue) && isUPPER(ceilvalue)))
3874                 {
3875                     if (isLOWER(prevvalue)) {
3876                         for (i = prevvalue; i <= ceilvalue; i++)
3877                             if (isLOWER(i))
3878                                 ANYOF_BITMAP_SET(ret, i);
3879                     } else {
3880                         for (i = prevvalue; i <= ceilvalue; i++)
3881                             if (isUPPER(i))
3882                                 ANYOF_BITMAP_SET(ret, i);
3883                     }
3884                 }
3885                 else
3886 #endif
3887                     for (i = prevvalue; i <= ceilvalue; i++)
3888                         ANYOF_BITMAP_SET(ret, i);
3889           }
3890           if (value > 255) {
3891                 ANYOF_FLAGS(ret) |= ANYOF_UNICODE;
3892                 if (prevvalue < value)
3893                     Perl_sv_catpvf(aTHX_ listsv, "%04"UVxf"\t%04"UVxf"\n",
3894                                    (UV)prevvalue, (UV)value);
3895                 else if (prevvalue == value)
3896                     Perl_sv_catpvf(aTHX_ listsv, "%04"UVxf"\n",
3897                                    (UV)value);
3898             }
3899         }
3900
3901         range = 0; /* this range (if it was one) is done now */
3902     }
3903
3904     if (need_class) {
3905         ANYOF_FLAGS(ret) |= ANYOF_LARGE;
3906         if (SIZE_ONLY)
3907             RExC_size += ANYOF_CLASS_ADD_SKIP;
3908         else
3909             RExC_emit += ANYOF_CLASS_ADD_SKIP;
3910     }
3911
3912     /* optimize case-insensitive simple patterns (e.g. /[a-z]/i) */
3913     if (!SIZE_ONLY &&
3914          /* If the only flag is folding (plus possibly inversion). */
3915         ((ANYOF_FLAGS(ret) & (ANYOF_FLAGS_ALL ^ ANYOF_INVERT)) == ANYOF_FOLD)
3916        ) {
3917         for (value = 0; value < 256; ++value) {
3918             if (ANYOF_BITMAP_TEST(ret, value)) {
3919                 IV fold = PL_fold[value];
3920
3921                 if (fold != value)
3922                     ANYOF_BITMAP_SET(ret, fold);
3923             }
3924         }
3925         ANYOF_FLAGS(ret) &= ~ANYOF_FOLD;
3926     }
3927
3928     /* optimize inverted simple patterns (e.g. [^a-z]) */
3929     if (!SIZE_ONLY && optimize_invert &&
3930         /* If the only flag is inversion. */
3931         (ANYOF_FLAGS(ret) & ANYOF_FLAGS_ALL) == ANYOF_INVERT) {
3932         for (value = 0; value < ANYOF_BITMAP_SIZE; ++value)
3933             ANYOF_BITMAP(ret)[value] ^= ANYOF_FLAGS_ALL;
3934         ANYOF_FLAGS(ret) = ANYOF_UNICODE_ALL;
3935     }
3936
3937     if (!SIZE_ONLY) {
3938         AV *av = newAV();
3939         SV *rv;
3940
3941         av_store(av, 0, listsv);
3942         av_store(av, 1, NULL);
3943         rv = newRV_noinc((SV*)av);
3944         n = add_data(pRExC_state, 1, "s");
3945         RExC_rx->data->data[n] = (void*)rv;
3946         ARG_SET(ret, n);
3947     }
3948
3949     return ret;
3950 }
3951
3952 STATIC char*
3953 S_nextchar(pTHX_ RExC_state_t *pRExC_state)
3954 {
3955     char* retval = RExC_parse++;
3956
3957     for (;;) {
3958         if (*RExC_parse == '(' && RExC_parse[1] == '?' &&
3959                 RExC_parse[2] == '#') {
3960             while (*RExC_parse && *RExC_parse != ')')
3961                 RExC_parse++;
3962             RExC_parse++;
3963             continue;
3964         }
3965         if (RExC_flags16 & PMf_EXTENDED) {
3966             if (isSPACE(*RExC_parse)) {
3967                 RExC_parse++;
3968                 continue;
3969             }
3970             else if (*RExC_parse == '#') {
3971                 while (*RExC_parse && *RExC_parse != '\n')
3972                     RExC_parse++;
3973                 RExC_parse++;
3974                 continue;
3975             }
3976         }
3977         return retval;
3978     }
3979 }
3980
3981 /*
3982 - reg_node - emit a node
3983 */
3984 STATIC regnode *                        /* Location. */
3985 S_reg_node(pTHX_ RExC_state_t *pRExC_state, U8 op)
3986 {
3987     register regnode *ret;
3988     register regnode *ptr;
3989
3990     ret = RExC_emit;
3991     if (SIZE_ONLY) {
3992         SIZE_ALIGN(RExC_size);
3993         RExC_size += 1;
3994         return(ret);
3995     }
3996
3997     NODE_ALIGN_FILL(ret);
3998     ptr = ret;
3999     FILL_ADVANCE_NODE(ptr, op);
4000     if (RExC_offsets) {         /* MJD */
4001       MJD_OFFSET_DEBUG((stderr, "%s:%u: (op %s) %s %u <- %u (len %u) (max %u).\n",
4002               "reg_node", __LINE__,
4003               reg_name[op],
4004               RExC_emit - RExC_emit_start > RExC_offsets[0]
4005               ? "Overwriting end of array!\n" : "OK",
4006               RExC_emit - RExC_emit_start,
4007               RExC_parse - RExC_start,
4008               RExC_offsets[0]));
4009       Set_Node_Offset(RExC_emit, RExC_parse + (op == END));
4010     }
4011
4012     RExC_emit = ptr;
4013
4014     return(ret);
4015 }
4016
4017 /*
4018 - reganode - emit a node with an argument
4019 */
4020 STATIC regnode *                        /* Location. */
4021 S_reganode(pTHX_ RExC_state_t *pRExC_state, U8 op, U32 arg)
4022 {
4023     register regnode *ret;
4024     register regnode *ptr;
4025
4026     ret = RExC_emit;
4027     if (SIZE_ONLY) {
4028         SIZE_ALIGN(RExC_size);
4029         RExC_size += 2;
4030         return(ret);
4031     }
4032
4033     NODE_ALIGN_FILL(ret);
4034     ptr = ret;
4035     FILL_ADVANCE_NODE_ARG(ptr, op, arg);
4036     if (RExC_offsets) {         /* MJD */
4037       MJD_OFFSET_DEBUG((stderr, "%s: %s %u <- %u (max %u).\n",
4038               "reganode",
4039               RExC_emit - RExC_emit_start > RExC_offsets[0] ?
4040               "Overwriting end of array!\n" : "OK",
4041               RExC_emit - RExC_emit_start,
4042               RExC_parse - RExC_start,
4043               RExC_offsets[0]));
4044       Set_Cur_Node_Offset;
4045     }
4046
4047     RExC_emit = ptr;
4048
4049     return(ret);
4050 }
4051
4052 /*
4053 - reguni - emit (if appropriate) a Unicode character
4054 */
4055 STATIC void
4056 S_reguni(pTHX_ RExC_state_t *pRExC_state, UV uv, char* s, STRLEN* lenp)
4057 {
4058     *lenp = SIZE_ONLY ? UNISKIP(uv) : (uvchr_to_utf8((U8*)s, uv) - (U8*)s);
4059 }
4060
4061 /*
4062 - reginsert - insert an operator in front of already-emitted operand
4063 *
4064 * Means relocating the operand.
4065 */
4066 STATIC void
4067 S_reginsert(pTHX_ RExC_state_t *pRExC_state, U8 op, regnode *opnd)
4068 {
4069     register regnode *src;
4070     register regnode *dst;
4071     register regnode *place;
4072     register int offset = regarglen[(U8)op];
4073
4074 /* (PL_regkind[(U8)op] == CURLY ? EXTRA_STEP_2ARGS : 0); */
4075
4076     if (SIZE_ONLY) {
4077         RExC_size += NODE_STEP_REGNODE + offset;
4078         return;
4079     }
4080
4081     src = RExC_emit;
4082     RExC_emit += NODE_STEP_REGNODE + offset;
4083     dst = RExC_emit;
4084     while (src > opnd) {
4085         StructCopy(--src, --dst, regnode);
4086         if (RExC_offsets) {     /* MJD 20010112 */
4087           MJD_OFFSET_DEBUG((stderr, "%s: %s copy %u -> %u (max %u).\n",
4088                   "reg_insert",
4089                   dst - RExC_emit_start > RExC_offsets[0]
4090                   ? "Overwriting end of array!\n" : "OK",
4091                   src - RExC_emit_start,
4092                   dst - RExC_emit_start,
4093                   RExC_offsets[0]));
4094           Set_Node_Offset_To_R(dst-RExC_emit_start, Node_Offset(src));
4095           Set_Node_Length_To_R(dst-RExC_emit_start, Node_Length(src));
4096         }
4097     }
4098
4099
4100     place = opnd;               /* Op node, where operand used to be. */
4101     if (RExC_offsets) {         /* MJD */
4102       MJD_OFFSET_DEBUG((stderr, "%s: %s %u <- %u (max %u).\n",
4103               "reginsert",
4104               place - RExC_emit_start > RExC_offsets[0]
4105               ? "Overwriting end of array!\n" : "OK",
4106               place - RExC_emit_start,
4107               RExC_parse - RExC_start,
4108               RExC_offsets[0]));
4109       Set_Node_Offset(place, RExC_parse);
4110     }
4111     src = NEXTOPER(place);
4112     FILL_ADVANCE_NODE(place, op);
4113     Zero(src, offset, regnode);
4114 }
4115
4116 /*
4117 - regtail - set the next-pointer at the end of a node chain of p to val.
4118 */
4119 STATIC void
4120 S_regtail(pTHX_ RExC_state_t *pRExC_state, regnode *p, regnode *val)
4121 {
4122     register regnode *scan;
4123     register regnode *temp;
4124
4125     if (SIZE_ONLY)
4126         return;
4127
4128     /* Find last node. */
4129     scan = p;
4130     for (;;) {
4131         temp = regnext(scan);
4132         if (temp == NULL)
4133             break;
4134         scan = temp;
4135     }
4136
4137     if (reg_off_by_arg[OP(scan)]) {
4138         ARG_SET(scan, val - scan);
4139     }
4140     else {
4141         NEXT_OFF(scan) = val - scan;
4142     }
4143 }
4144
4145 /*
4146 - regoptail - regtail on operand of first argument; nop if operandless
4147 */
4148 STATIC void
4149 S_regoptail(pTHX_ RExC_state_t *pRExC_state, regnode *p, regnode *val)
4150 {
4151     /* "Operandless" and "op != BRANCH" are synonymous in practice. */
4152     if (p == NULL || SIZE_ONLY)
4153         return;
4154     if (PL_regkind[(U8)OP(p)] == BRANCH) {
4155         regtail(pRExC_state, NEXTOPER(p), val);
4156     }
4157     else if ( PL_regkind[(U8)OP(p)] == BRANCHJ) {
4158         regtail(pRExC_state, NEXTOPER(NEXTOPER(p)), val);
4159     }
4160     else
4161         return;
4162 }
4163
4164 /*
4165  - regcurly - a little FSA that accepts {\d+,?\d*}
4166  */
4167 STATIC I32
4168 S_regcurly(pTHX_ register char *s)
4169 {
4170     if (*s++ != '{')
4171         return FALSE;
4172     if (!isDIGIT(*s))
4173         return FALSE;
4174     while (isDIGIT(*s))
4175         s++;
4176     if (*s == ',')
4177         s++;
4178     while (isDIGIT(*s))
4179         s++;
4180     if (*s != '}')
4181         return FALSE;
4182     return TRUE;
4183 }
4184
4185
4186 #ifdef DEBUGGING
4187
4188 STATIC regnode *
4189 S_dumpuntil(pTHX_ regnode *start, regnode *node, regnode *last, SV* sv, I32 l)
4190 {
4191     register U8 op = EXACT;     /* Arbitrary non-END op. */
4192     register regnode *next;
4193
4194     while (op != END && (!last || node < last)) {
4195         /* While that wasn't END last time... */
4196
4197         NODE_ALIGN(node);
4198         op = OP(node);
4199         if (op == CLOSE)
4200             l--;
4201         next = regnext(node);
4202         /* Where, what. */
4203         if (OP(node) == OPTIMIZED)
4204             goto after_print;
4205         regprop(sv, node);
4206         PerlIO_printf(Perl_debug_log, "%4"IVdf":%*s%s", (IV)(node - start),
4207                       (int)(2*l + 1), "", SvPVX(sv));
4208         if (next == NULL)               /* Next ptr. */
4209             PerlIO_printf(Perl_debug_log, "(0)");
4210         else
4211             PerlIO_printf(Perl_debug_log, "(%"IVdf")", (IV)(next - start));
4212         (void)PerlIO_putc(Perl_debug_log, '\n');
4213       after_print:
4214         if (PL_regkind[(U8)op] == BRANCHJ) {
4215             register regnode *nnode = (OP(next) == LONGJMP
4216                                        ? regnext(next)
4217                                        : next);
4218             if (last && nnode > last)
4219                 nnode = last;
4220             node = dumpuntil(start, NEXTOPER(NEXTOPER(node)), nnode, sv, l + 1);
4221         }
4222         else if (PL_regkind[(U8)op] == BRANCH) {
4223             node = dumpuntil(start, NEXTOPER(node), next, sv, l + 1);
4224         }
4225         else if ( op == CURLY) {   /* `next' might be very big: optimizer */
4226             node = dumpuntil(start, NEXTOPER(node) + EXTRA_STEP_2ARGS,
4227                              NEXTOPER(node) + EXTRA_STEP_2ARGS + 1, sv, l + 1);
4228         }
4229         else if (PL_regkind[(U8)op] == CURLY && op != CURLYX) {
4230             node = dumpuntil(start, NEXTOPER(node) + EXTRA_STEP_2ARGS,
4231                              next, sv, l + 1);
4232         }
4233         else if ( op == PLUS || op == STAR) {
4234             node = dumpuntil(start, NEXTOPER(node), NEXTOPER(node) + 1, sv, l + 1);
4235         }
4236         else if (op == ANYOF) {
4237             /* arglen 1 + class block */
4238             node += 1 + ((ANYOF_FLAGS(node) & ANYOF_LARGE)
4239                     ? ANYOF_CLASS_SKIP : ANYOF_SKIP);
4240             node = NEXTOPER(node);
4241         }
4242         else if (PL_regkind[(U8)op] == EXACT) {
4243             /* Literal string, where present. */
4244             node += NODE_SZ_STR(node) - 1;
4245             node = NEXTOPER(node);
4246         }
4247         else {
4248             node = NEXTOPER(node);
4249             node += regarglen[(U8)op];
4250         }
4251         if (op == CURLYX || op == OPEN)
4252             l++;
4253         else if (op == WHILEM)
4254             l--;
4255     }
4256     return node;
4257 }
4258
4259 #endif  /* DEBUGGING */
4260
4261 /*
4262  - regdump - dump a regexp onto Perl_debug_log in vaguely comprehensible form
4263  */
4264 void
4265 Perl_regdump(pTHX_ regexp *r)
4266 {
4267 #ifdef DEBUGGING
4268     SV *sv = sv_newmortal();
4269
4270     (void)dumpuntil(r->program, r->program + 1, NULL, sv, 0);
4271
4272     /* Header fields of interest. */
4273     if (r->anchored_substr)
4274         PerlIO_printf(Perl_debug_log,
4275                       "anchored `%s%.*s%s'%s at %"IVdf" ",
4276                       PL_colors[0],
4277                       (int)(SvCUR(r->anchored_substr) - (SvTAIL(r->anchored_substr)!=0)),
4278                       SvPVX(r->anchored_substr),
4279                       PL_colors[1],
4280                       SvTAIL(r->anchored_substr) ? "$" : "",
4281                       (IV)r->anchored_offset);
4282     if (r->float_substr)
4283         PerlIO_printf(Perl_debug_log,
4284                       "floating `%s%.*s%s'%s at %"IVdf"..%"UVuf" ",
4285                       PL_colors[0],
4286                       (int)(SvCUR(r->float_substr) - (SvTAIL(r->float_substr)!=0)),
4287                       SvPVX(r->float_substr),
4288                       PL_colors[1],
4289                       SvTAIL(r->float_substr) ? "$" : "",
4290                       (IV)r->float_min_offset, (UV)r->float_max_offset);
4291     if (r->check_substr)
4292         PerlIO_printf(Perl_debug_log,
4293                       r->check_substr == r->float_substr
4294                       ? "(checking floating" : "(checking anchored");
4295     if (r->reganch & ROPT_NOSCAN)
4296         PerlIO_printf(Perl_debug_log, " noscan");
4297     if (r->reganch & ROPT_CHECK_ALL)
4298         PerlIO_printf(Perl_debug_log, " isall");
4299     if (r->check_substr)
4300         PerlIO_printf(Perl_debug_log, ") ");
4301
4302     if (r->regstclass) {
4303         regprop(sv, r->regstclass);
4304         PerlIO_printf(Perl_debug_log, "stclass `%s' ", SvPVX(sv));
4305     }
4306     if (r->reganch & ROPT_ANCH) {
4307         PerlIO_printf(Perl_debug_log, "anchored");
4308         if (r->reganch & ROPT_ANCH_BOL)
4309             PerlIO_printf(Perl_debug_log, "(BOL)");
4310         if (r->reganch & ROPT_ANCH_MBOL)
4311             PerlIO_printf(Perl_debug_log, "(MBOL)");
4312         if (r->reganch & ROPT_ANCH_SBOL)
4313             PerlIO_printf(Perl_debug_log, "(SBOL)");
4314         if (r->reganch & ROPT_ANCH_GPOS)
4315             PerlIO_printf(Perl_debug_log, "(GPOS)");
4316         PerlIO_putc(Perl_debug_log, ' ');
4317     }
4318     if (r->reganch & ROPT_GPOS_SEEN)
4319         PerlIO_printf(Perl_debug_log, "GPOS ");
4320     if (r->reganch & ROPT_SKIP)
4321         PerlIO_printf(Perl_debug_log, "plus ");
4322     if (r->reganch & ROPT_IMPLICIT)
4323         PerlIO_printf(Perl_debug_log, "implicit ");
4324     PerlIO_printf(Perl_debug_log, "minlen %ld ", (long) r->minlen);
4325     if (r->reganch & ROPT_EVAL_SEEN)
4326         PerlIO_printf(Perl_debug_log, "with eval ");
4327     PerlIO_printf(Perl_debug_log, "\n");
4328     if (r->offsets) {
4329       U32 i;
4330       U32 len = r->offsets[0];
4331       PerlIO_printf(Perl_debug_log, "Offsets: [%"UVuf"]\n\t", (UV)r->offsets[0]);
4332       for (i = 1; i <= len; i++)
4333         PerlIO_printf(Perl_debug_log, "%"UVuf"[%"UVuf"] ",
4334                       (UV)r->offsets[i*2-1],
4335                       (UV)r->offsets[i*2]);
4336       PerlIO_printf(Perl_debug_log, "\n");
4337     }
4338 #endif  /* DEBUGGING */
4339 }
4340
4341 #ifdef DEBUGGING
4342
4343 STATIC void
4344 S_put_byte(pTHX_ SV *sv, int c)
4345 {
4346     if (isCNTRL(c) || c == 127 || c == 255 || !isPRINT(c))
4347         Perl_sv_catpvf(aTHX_ sv, "\\%o", c);
4348     else if (c == '-' || c == ']' || c == '\\' || c == '^')
4349         Perl_sv_catpvf(aTHX_ sv, "\\%c", c);
4350     else
4351         Perl_sv_catpvf(aTHX_ sv, "%c", c);
4352 }
4353
4354 #endif  /* DEBUGGING */
4355
4356 /*
4357 - regprop - printable representation of opcode
4358 */
4359 void
4360 Perl_regprop(pTHX_ SV *sv, regnode *o)
4361 {
4362 #ifdef DEBUGGING
4363     register int k;
4364
4365     sv_setpvn(sv, "", 0);
4366     if (OP(o) >= reg_num)               /* regnode.type is unsigned */
4367         /* It would be nice to FAIL() here, but this may be called from
4368            regexec.c, and it would be hard to supply pRExC_state. */
4369         Perl_croak(aTHX_ "Corrupted regexp opcode");
4370     sv_catpv(sv, (char*)reg_name[OP(o)]); /* Take off const! */
4371
4372     k = PL_regkind[(U8)OP(o)];
4373
4374     if (k == EXACT)
4375         Perl_sv_catpvf(aTHX_ sv, " <%s%.*s%s>", PL_colors[0],
4376                        STR_LEN(o), STRING(o), PL_colors[1]);
4377     else if (k == CURLY) {
4378         if (OP(o) == CURLYM || OP(o) == CURLYN || OP(o) == CURLYX)
4379             Perl_sv_catpvf(aTHX_ sv, "[%d]", o->flags); /* Parenth number */
4380         Perl_sv_catpvf(aTHX_ sv, " {%d,%d}", ARG1(o), ARG2(o));
4381     }
4382     else if (k == WHILEM && o->flags)                   /* Ordinal/of */
4383         Perl_sv_catpvf(aTHX_ sv, "[%d/%d]", o->flags & 0xf, o->flags>>4);
4384     else if (k == REF || k == OPEN || k == CLOSE || k == GROUPP )
4385         Perl_sv_catpvf(aTHX_ sv, "%d", (int)ARG(o));    /* Parenth number */
4386     else if (k == LOGICAL)
4387         Perl_sv_catpvf(aTHX_ sv, "[%d]", o->flags);     /* 2: embedded, otherwise 1 */
4388     else if (k == ANYOF) {
4389         int i, rangestart = -1;
4390         U8 flags = ANYOF_FLAGS(o);
4391         const char * const anyofs[] = { /* Should be syncronized with
4392                                          * ANYOF_ #xdefines in regcomp.h */
4393             "\\w",
4394             "\\W",
4395             "\\s",
4396             "\\S",
4397             "\\d",
4398             "\\D",
4399             "[:alnum:]",
4400             "[:^alnum:]",
4401             "[:alpha:]",
4402             "[:^alpha:]",
4403             "[:ascii:]",
4404             "[:^ascii:]",
4405             "[:ctrl:]",
4406             "[:^ctrl:]",
4407             "[:graph:]",
4408             "[:^graph:]",
4409             "[:lower:]",
4410             "[:^lower:]",
4411             "[:print:]",
4412             "[:^print:]",
4413             "[:punct:]",
4414             "[:^punct:]",
4415             "[:upper:]",
4416             "[:^upper:]",
4417             "[:xdigit:]",
4418             "[:^xdigit:]",
4419             "[:space:]",
4420             "[:^space:]",
4421             "[:blank:]",
4422             "[:^blank:]"
4423         };
4424
4425         if (flags & ANYOF_LOCALE)
4426             sv_catpv(sv, "{loc}");
4427         if (flags & ANYOF_FOLD)
4428             sv_catpv(sv, "{i}");
4429         Perl_sv_catpvf(aTHX_ sv, "[%s", PL_colors[0]);
4430         if (flags & ANYOF_INVERT)
4431             sv_catpv(sv, "^");
4432         for (i = 0; i <= 256; i++) {
4433             if (i < 256 && ANYOF_BITMAP_TEST(o,i)) {
4434                 if (rangestart == -1)
4435                     rangestart = i;
4436             } else if (rangestart != -1) {
4437                 if (i <= rangestart + 3)
4438                     for (; rangestart < i; rangestart++)
4439                         put_byte(sv, rangestart);
4440                 else {
4441                     put_byte(sv, rangestart);
4442                     sv_catpv(sv, "-");
4443                     put_byte(sv, i - 1);
4444                 }
4445                 rangestart = -1;
4446             }
4447         }
4448
4449         if (o->flags & ANYOF_CLASS)
4450             for (i = 0; i < sizeof(anyofs)/sizeof(char*); i++)
4451                 if (ANYOF_CLASS_TEST(o,i))
4452                     sv_catpv(sv, anyofs[i]);
4453
4454         if (flags & ANYOF_UNICODE)
4455             sv_catpv(sv, "{unicode}");
4456         else if (flags & ANYOF_UNICODE_ALL)
4457             sv_catpv(sv, "{all-unicode}");
4458
4459         {
4460             SV *lv;
4461             SV *sw = regclass_swash(o, FALSE, &lv);
4462
4463             if (lv) {
4464                 if (sw) {
4465                     UV i;
4466                     U8 s[UTF8_MAXLEN+1];
4467
4468                     for (i = 0; i <= 256; i++) { /* just the first 256 */
4469                         U8 *e = uvchr_to_utf8(s, i);
4470
4471                         if (i < 256 && swash_fetch(sw, s, TRUE)) {
4472                             if (rangestart == -1)
4473                                 rangestart = i;
4474                         } else if (rangestart != -1) {
4475                             U8 *p;
4476
4477                             if (i <= rangestart + 3)
4478                                 for (; rangestart < i; rangestart++) {
4479                                     for(e = uvchr_to_utf8(s, rangestart), p = s; p < e; p++)
4480                                         put_byte(sv, *p);
4481                                 }
4482                             else {
4483                                 for (e = uvchr_to_utf8(s, rangestart), p = s; p < e; p++)
4484                                     put_byte(sv, *p);
4485                                 sv_catpv(sv, "-");
4486                                     for (e = uvchr_to_utf8(s, i - 1), p = s; p < e; p++)
4487                                         put_byte(sv, *p);
4488                                 }
4489                                 rangestart = -1;
4490                             }
4491                         }
4492
4493                     sv_catpv(sv, "..."); /* et cetera */
4494                 }
4495
4496                 {
4497                     char *s = savepv(SvPVX(lv));
4498                     char *origs = s;
4499
4500                     while(*s && *s != '\n') s++;
4501
4502                     if (*s == '\n') {
4503                         char *t = ++s;
4504
4505                         while (*s) {
4506                             if (*s == '\n')
4507                                 *s = ' ';
4508                             s++;
4509                         }
4510                         if (s[-1] == ' ')
4511                             s[-1] = 0;
4512
4513                         sv_catpv(sv, t);
4514                     }
4515
4516                     Safefree(origs);
4517                 }
4518             }
4519         }
4520
4521         Perl_sv_catpvf(aTHX_ sv, "%s]", PL_colors[1]);
4522     }
4523     else if (k == BRANCHJ && (OP(o) == UNLESSM || OP(o) == IFMATCH))
4524         Perl_sv_catpvf(aTHX_ sv, "[-%d]", o->flags);
4525 #endif  /* DEBUGGING */
4526 }
4527
4528 SV *
4529 Perl_re_intuit_string(pTHX_ regexp *prog)
4530 {                               /* Assume that RE_INTUIT is set */
4531     DEBUG_r(
4532         {   STRLEN n_a;
4533             char *s = SvPV(prog->check_substr,n_a);
4534
4535             if (!PL_colorset) reginitcolors();
4536             PerlIO_printf(Perl_debug_log,
4537                       "%sUsing REx substr:%s `%s%.60s%s%s'\n",
4538                       PL_colors[4],PL_colors[5],PL_colors[0],
4539                       s,
4540                       PL_colors[1],
4541                       (strlen(s) > 60 ? "..." : ""));
4542         } );
4543
4544     return prog->check_substr;
4545 }
4546
4547 void
4548 Perl_pregfree(pTHX_ struct regexp *r)
4549 {
4550     DEBUG_r(if (!PL_colorset) reginitcolors());
4551
4552     if (!r || (--r->refcnt > 0))
4553         return;
4554     DEBUG_r(PerlIO_printf(Perl_debug_log,
4555                       "%sFreeing REx:%s `%s%.60s%s%s'\n",
4556                       PL_colors[4],PL_colors[5],PL_colors[0],
4557                       r->precomp,
4558                       PL_colors[1],
4559                       (strlen(r->precomp) > 60 ? "..." : "")));
4560
4561     if (r->precomp)
4562         Safefree(r->precomp);
4563     if (r->offsets)             /* 20010421 MJD */
4564         Safefree(r->offsets);
4565     if (RX_MATCH_COPIED(r))
4566         Safefree(r->subbeg);
4567     if (r->substrs) {
4568         if (r->anchored_substr)
4569             SvREFCNT_dec(r->anchored_substr);
4570         if (r->float_substr)
4571             SvREFCNT_dec(r->float_substr);
4572         Safefree(r->substrs);
4573     }
4574     if (r->data) {
4575         int n = r->data->count;
4576         AV* new_comppad = NULL;
4577         AV* old_comppad;
4578         SV** old_curpad;
4579
4580         while (--n >= 0) {
4581             switch (r->data->what[n]) {
4582             case 's':
4583                 SvREFCNT_dec((SV*)r->data->data[n]);
4584                 break;
4585             case 'f':
4586                 Safefree(r->data->data[n]);
4587                 break;
4588             case 'p':
4589                 new_comppad = (AV*)r->data->data[n];
4590                 break;
4591             case 'o':
4592                 if (new_comppad == NULL)
4593                     Perl_croak(aTHX_ "panic: pregfree comppad");
4594                 old_comppad = PL_comppad;
4595                 old_curpad = PL_curpad;
4596                 /* Watch out for global destruction's random ordering. */
4597                 if (SvTYPE(new_comppad) == SVt_PVAV) {
4598                     PL_comppad = new_comppad;
4599                     PL_curpad = AvARRAY(new_comppad);
4600                 }
4601                 else
4602                     PL_curpad = NULL;
4603                 op_free((OP_4tree*)r->data->data[n]);
4604                 PL_comppad = old_comppad;
4605                 PL_curpad = old_curpad;
4606                 SvREFCNT_dec((SV*)new_comppad);
4607                 new_comppad = NULL;
4608                 break;
4609             case 'n':
4610                 break;
4611             default:
4612                 Perl_croak(aTHX_ "panic: regfree data code '%c'", r->data->what[n]);
4613             }
4614         }
4615         Safefree(r->data->what);
4616         Safefree(r->data);
4617     }
4618     Safefree(r->startp);
4619     Safefree(r->endp);
4620     Safefree(r);
4621 }
4622
4623 /*
4624  - regnext - dig the "next" pointer out of a node
4625  *
4626  * [Note, when REGALIGN is defined there are two places in regmatch()
4627  * that bypass this code for speed.]
4628  */
4629 regnode *
4630 Perl_regnext(pTHX_ register regnode *p)
4631 {
4632     register I32 offset;
4633
4634     if (p == &PL_regdummy)
4635         return(NULL);
4636
4637     offset = (reg_off_by_arg[OP(p)] ? ARG(p) : NEXT_OFF(p));
4638     if (offset == 0)
4639         return(NULL);
4640
4641     return(p+offset);
4642 }
4643
4644 STATIC void
4645 S_re_croak2(pTHX_ const char* pat1,const char* pat2,...)
4646 {
4647     va_list args;
4648     STRLEN l1 = strlen(pat1);
4649     STRLEN l2 = strlen(pat2);
4650     char buf[512];
4651     SV *msv;
4652     char *message;
4653
4654     if (l1 > 510)
4655         l1 = 510;
4656     if (l1 + l2 > 510)
4657         l2 = 510 - l1;
4658     Copy(pat1, buf, l1 , char);
4659     Copy(pat2, buf + l1, l2 , char);
4660     buf[l1 + l2] = '\n';
4661     buf[l1 + l2 + 1] = '\0';
4662 #ifdef I_STDARG
4663     /* ANSI variant takes additional second argument */
4664     va_start(args, pat2);
4665 #else
4666     va_start(args);
4667 #endif
4668     msv = vmess(buf, &args);
4669     va_end(args);
4670     message = SvPV(msv,l1);
4671     if (l1 > 512)
4672         l1 = 512;
4673     Copy(message, buf, l1 , char);
4674     buf[l1] = '\0';                     /* Overwrite \n */
4675     Perl_croak(aTHX_ "%s", buf);
4676 }
4677
4678 /* XXX Here's a total kludge.  But we need to re-enter for swash routines. */
4679
4680 void
4681 Perl_save_re_context(pTHX)
4682 {
4683 #if 0
4684     SAVEPPTR(RExC_precomp);             /* uncompiled string. */
4685     SAVEI32(RExC_npar);         /* () count. */
4686     SAVEI32(RExC_size);         /* Code size. */
4687     SAVEI16(RExC_flags16);              /* are we folding, multilining? */
4688     SAVEVPTR(RExC_rx);          /* from regcomp.c */
4689     SAVEI32(RExC_seen);         /* from regcomp.c */
4690     SAVEI32(RExC_sawback);              /* Did we see \1, ...? */
4691     SAVEI32(RExC_naughty);              /* How bad is this pattern? */
4692     SAVEVPTR(RExC_emit);                /* Code-emit pointer; &regdummy = don't */
4693     SAVEPPTR(RExC_end);         /* End of input for compile */
4694     SAVEPPTR(RExC_parse);               /* Input-scan pointer. */
4695 #endif
4696
4697     SAVEI32(PL_reg_flags);              /* from regexec.c */
4698     SAVEPPTR(PL_bostr);
4699     SAVEPPTR(PL_reginput);              /* String-input pointer. */
4700     SAVEPPTR(PL_regbol);                /* Beginning of input, for ^ check. */
4701     SAVEPPTR(PL_regeol);                /* End of input, for $ check. */
4702     SAVEVPTR(PL_regstartp);             /* Pointer to startp array. */
4703     SAVEVPTR(PL_regendp);               /* Ditto for endp. */
4704     SAVEVPTR(PL_reglastparen);          /* Similarly for lastparen. */
4705     SAVEPPTR(PL_regtill);               /* How far we are required to go. */
4706     SAVEGENERICPV(PL_reg_start_tmp);            /* from regexec.c */
4707     PL_reg_start_tmp = 0;
4708     SAVEI32(PL_reg_start_tmpl);         /* from regexec.c */
4709     PL_reg_start_tmpl = 0;
4710     SAVEVPTR(PL_regdata);
4711     SAVEI32(PL_reg_eval_set);           /* from regexec.c */
4712     SAVEI32(PL_regnarrate);             /* from regexec.c */
4713     SAVEVPTR(PL_regprogram);            /* from regexec.c */
4714     SAVEINT(PL_regindent);              /* from regexec.c */
4715     SAVEVPTR(PL_regcc);                 /* from regexec.c */
4716     SAVEVPTR(PL_curcop);
4717     SAVEVPTR(PL_reg_call_cc);           /* from regexec.c */
4718     SAVEVPTR(PL_reg_re);                /* from regexec.c */
4719     SAVEPPTR(PL_reg_ganch);             /* from regexec.c */
4720     SAVESPTR(PL_reg_sv);                /* from regexec.c */
4721     SAVEVPTR(PL_reg_magic);             /* from regexec.c */
4722     SAVEI32(PL_reg_oldpos);                     /* from regexec.c */
4723     SAVEVPTR(PL_reg_oldcurpm);          /* from regexec.c */
4724     SAVEVPTR(PL_reg_curpm);             /* from regexec.c */
4725     SAVEI32(PL_regnpar);                /* () count. */
4726     SAVEI32(PL_regsize);                /* from regexec.c */
4727 #ifdef DEBUGGING
4728     SAVEPPTR(PL_reg_starttry);          /* from regexec.c */
4729 #endif
4730 }
4731
4732 #ifdef PERL_OBJECT
4733 #include "XSUB.h"
4734 #undef this
4735 #define this pPerl
4736 #endif
4737
4738 static void
4739 clear_re(pTHXo_ void *r)
4740 {
4741     ReREFCNT_dec((regexp *)r);
4742 }
4743