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remove REGMATCH detritus and shrink the size of the backtrack structure
[perl5.git] / regexp.h
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a0d0e21e 1/* regexp.h
d6376244 2 *
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3 * Copyright (C) 1993, 1994, 1996, 1997, 1999, 2000, 2001, 2003,
4 * by Larry Wall and others
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5 *
6 * You may distribute under the terms of either the GNU General Public
7 * License or the Artistic License, as specified in the README file.
8 *
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9 */
10
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11/*
12 * Definitions etc. for regexp(3) routines.
13 *
14 * Caveat: this is V8 regexp(3) [actually, a reimplementation thereof],
15 * not the System V one.
16 */
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17#ifndef PLUGGABLE_RE_EXTENSION
18/* we don't want to include this stuff if we are inside Nicholas'
19 * pluggable regex engine code */
378cc40b 20
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21struct regnode {
22 U8 flags;
23 U8 type;
24 U16 next_off;
25};
26
27typedef struct regnode regnode;
28
cad2e5aa 29struct reg_substr_data;
2779dcf1 30
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31struct reg_data;
32
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33struct regexp_engine;
34
378cc40b 35typedef struct regexp {
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36 I32 *startp;
37 I32 *endp;
c277df42 38 regnode *regstclass;
2779dcf1 39 struct reg_substr_data *substrs;
cf93c79d 40 char *precomp; /* pre-compilation regular expression */
c277df42 41 struct reg_data *data; /* Additional data. */
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42 char *subbeg; /* saved or original string
43 so \digit works forever. */
f8c7b90f 44#ifdef PERL_OLD_COPY_ON_WRITE
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45 SV *saved_copy; /* If non-NULL, SV which is COW from original */
46#endif
fac92740 47 U32 *offsets; /* offset annotations 20001228 MJD */
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48 I32 sublen; /* Length of string pointed by subbeg */
49 I32 refcnt;
50 I32 minlen; /* mininum possible length of $& */
51 I32 prelen; /* length of precomp */
52 U32 nparens; /* number of parentheses */
53 U32 lastparen; /* last paren matched */
a01268b5 54 U32 lastcloseparen; /* last paren matched */
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55 U32 reganch; /* Internal use only +
56 Tainted information used by regexec? */
f9f4320a 57 const struct regexp_engine* engine;
c277df42 58 regnode program[1]; /* Unwarranted chumminess with compiler. */
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59} regexp;
60
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61
62typedef struct re_scream_pos_data_s
63{
64 char **scream_olds; /* match pos */
65 I32 *scream_pos; /* Internal iterator of scream. */
66} re_scream_pos_data;
67
68typedef struct regexp_engine {
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69 regexp* (*comp) (pTHX_ char* exp, char* xend, PMOP* pm);
70 I32 (*exec) (pTHX_ regexp* prog, char* stringarg, char* strend,
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71 char* strbeg, I32 minend, SV* screamer,
72 void* data, U32 flags);
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73 char* (*intuit) (pTHX_ regexp *prog, SV *sv, char *strpos,
74 char *strend, U32 flags,
75 struct re_scream_pos_data_s *data);
76 SV* (*checkstr) (pTHX_ regexp *prog);
77 void (*free) (pTHX_ struct regexp* r);
78#ifdef USE_ITHREADS
79 regexp* (*dupe) (pTHX_ const regexp *r, CLONE_PARAMS *param);
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80#endif
81} regexp_engine;
82
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83#define ROPT_ANCH (ROPT_ANCH_BOL|ROPT_ANCH_MBOL|ROPT_ANCH_GPOS|ROPT_ANCH_SBOL)
84#define ROPT_ANCH_SINGLE (ROPT_ANCH_SBOL|ROPT_ANCH_GPOS)
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85#define ROPT_ANCH_BOL 0x00000001
86#define ROPT_ANCH_MBOL 0x00000002
87#define ROPT_ANCH_SBOL 0x00000004
88#define ROPT_ANCH_GPOS 0x00000008
89#define ROPT_SKIP 0x00000010
90#define ROPT_IMPLICIT 0x00000020 /* Converted .* to ^.* */
91#define ROPT_NOSCAN 0x00000040 /* Check-string always at start. */
92#define ROPT_GPOS_SEEN 0x00000080
93#define ROPT_CHECK_ALL 0x00000100
94#define ROPT_LOOKBEHIND_SEEN 0x00000200
95#define ROPT_EVAL_SEEN 0x00000400
96#define ROPT_CANY_SEEN 0x00000800
cce850e4 97#define ROPT_SANY_SEEN ROPT_CANY_SEEN /* src bckwrd cmpt */
f9f4320a 98#define ROPT_GPOS_CHECK (ROPT_GPOS_SEEN|ROPT_ANCH_GPOS)
6bda09f9 99#define ROPT_RECURSE_SEEN 0x00001000
a0ed51b3 100
8782bef2 101/* 0xf800 of reganch is used by PMf_COMPILETIME */
c277df42 102
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103#define ROPT_UTF8 0x00010000
104#define ROPT_NAUGHTY 0x00020000 /* how exponential is this pattern? */
105#define ROPT_COPY_DONE 0x00040000 /* subbeg is a copy of the string */
106#define ROPT_TAINTED_SEEN 0x00080000
a30b2f1f 107#define ROPT_MATCH_UTF8 0x10000000 /* subbeg is utf-8 */
a0ed51b3 108
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109#define RE_USE_INTUIT_NOML 0x00100000 /* Best to intuit before matching */
110#define RE_USE_INTUIT_ML 0x00200000
111#define REINT_AUTORITATIVE_NOML 0x00400000 /* Can trust a positive answer */
be8e71aa 112#define REINT_AUTORITATIVE_ML 0x00800000
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113#define REINT_ONCE_NOML 0x01000000 /* Intuit can succed once only. */
114#define REINT_ONCE_ML 0x02000000
115#define RE_INTUIT_ONECHAR 0x04000000
116#define RE_INTUIT_TAIL 0x08000000
117
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118
119#define RE_USE_INTUIT (RE_USE_INTUIT_NOML|RE_USE_INTUIT_ML)
120#define REINT_AUTORITATIVE (REINT_AUTORITATIVE_NOML|REINT_AUTORITATIVE_ML)
121#define REINT_ONCE (REINT_ONCE_NOML|REINT_ONCE_ML)
122
c277df42 123#define RX_MATCH_TAINTED(prog) ((prog)->reganch & ROPT_TAINTED_SEEN)
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124#define RX_MATCH_TAINTED_on(prog) ((prog)->reganch |= ROPT_TAINTED_SEEN)
125#define RX_MATCH_TAINTED_off(prog) ((prog)->reganch &= ~ROPT_TAINTED_SEEN)
126#define RX_MATCH_TAINTED_set(prog, t) ((t) \
127 ? RX_MATCH_TAINTED_on(prog) \
128 : RX_MATCH_TAINTED_off(prog))
c277df42 129
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130#define RX_MATCH_COPIED(prog) ((prog)->reganch & ROPT_COPY_DONE)
131#define RX_MATCH_COPIED_on(prog) ((prog)->reganch |= ROPT_COPY_DONE)
132#define RX_MATCH_COPIED_off(prog) ((prog)->reganch &= ~ROPT_COPY_DONE)
133#define RX_MATCH_COPIED_set(prog,t) ((t) \
134 ? RX_MATCH_COPIED_on(prog) \
135 : RX_MATCH_COPIED_off(prog))
f9f4320a 136
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137#endif /* PLUGGABLE_RE_EXTENSION */
138
139/* Stuff that needs to be included in the plugable extension goes below here */
140
141#define RE_DEBUG_BIT 0x20000000
142#define RX_DEBUG(prog) ((prog)->reganch & RE_DEBUG_BIT)
143#define RX_DEBUG_on(prog) ((prog)->reganch |= RE_DEBUG_BIT)
cf93c79d 144
f8c7b90f 145#ifdef PERL_OLD_COPY_ON_WRITE
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146#define RX_MATCH_COPY_FREE(rx) \
147 STMT_START {if (rx->saved_copy) { \
148 SV_CHECK_THINKFIRST_COW_DROP(rx->saved_copy); \
149 } \
150 if (RX_MATCH_COPIED(rx)) { \
151 Safefree(rx->subbeg); \
152 RX_MATCH_COPIED_off(rx); \
153 }} STMT_END
154#else
155#define RX_MATCH_COPY_FREE(rx) \
156 STMT_START {if (RX_MATCH_COPIED(rx)) { \
157 Safefree(rx->subbeg); \
158 RX_MATCH_COPIED_off(rx); \
159 }} STMT_END
160#endif
161
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162#define RX_MATCH_UTF8(prog) ((prog)->reganch & ROPT_MATCH_UTF8)
163#define RX_MATCH_UTF8_on(prog) ((prog)->reganch |= ROPT_MATCH_UTF8)
164#define RX_MATCH_UTF8_off(prog) ((prog)->reganch &= ~ROPT_MATCH_UTF8)
165#define RX_MATCH_UTF8_set(prog, t) ((t) \
166 ? (RX_MATCH_UTF8_on(prog), (PL_reg_match_utf8 = 1)) \
167 : (RX_MATCH_UTF8_off(prog), (PL_reg_match_utf8 = 0)))
168
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169#define REXEC_COPY_STR 0x01 /* Need to copy the string. */
170#define REXEC_CHECKED 0x02 /* check_substr already checked. */
171#define REXEC_SCREAM 0x04 /* use scream table. */
172#define REXEC_IGNOREPOS 0x08 /* \G matches at start. */
cf93c79d 173#define REXEC_NOT_FIRST 0x10 /* This is another iteration of //g. */
c277df42 174
155aba94 175#define ReREFCNT_inc(re) ((void)(re && re->refcnt++), re)
f9f4320a 176#define ReREFCNT_dec(re) CALLREGFREE(re)
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177
178#define FBMcf_TAIL_DOLLAR 1
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179#define FBMcf_TAIL_DOLLARM 2
180#define FBMcf_TAIL_Z 4
181#define FBMcf_TAIL_z 8
182#define FBMcf_TAIL (FBMcf_TAIL_DOLLAR|FBMcf_TAIL_DOLLARM|FBMcf_TAIL_Z|FBMcf_TAIL_z)
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183
184#define FBMrf_MULTILINE 1
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185
186struct re_scream_pos_data_s;
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187
188/* an accepting state/position*/
189struct _reg_trie_accepted {
190 U8 *endpos;
191 U16 wordnum;
192};
193typedef struct _reg_trie_accepted reg_trie_accepted;
194
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195/* some basic information about the current match that is created by
196 * Perl_regexec_flags and then passed to regtry(), regmatch() etc */
197
198typedef struct {
199 regexp *prog;
200 char *bol;
201 char *till;
202 SV *sv;
203 char *ganch;
204} regmatch_info;
205
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206
207/* structures for holding and saving the state maintained by regmatch() */
208
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209#define MAX_RECURSE_EVAL_NOCHANGE_DEPTH 50
210
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211typedef I32 CHECKPOINT;
212
a0374537 213typedef struct regmatch_state {
40a82448 214 int resume_state; /* where to jump to on return */
24d3c4a9 215 char *locinput; /* where to backtrack in string on failure */
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216
217 union {
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218
219 /* this is a fake union member that matches the first element
220 * of each member that needs to store positive backtrack
221 * information */
222 struct {
223 struct regmatch_state *prev_yes_state;
224 } yes;
225
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226 struct {
227 reg_trie_accepted *accept_buff;
166ba7cd 228 U32 accepted; /* how many accepting states we have seen */
786e8c11 229 U16 *jump; /* negative offsets from B */
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230 regnode *B; /* node following the trie */
231 regnode *me; /* only needed for debugging */
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232 } trie;
233
234 struct {
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235 /* this first element must match u.yes */
236 struct regmatch_state *prev_yes_state;
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237 struct regmatch_state *prev_eval;
238 struct regmatch_state *prev_curlyx;
aa283a38 239 regexp *prev_rex;
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240 U32 toggle_reg_flags; /* what bits in PL_reg_flags to
241 flip when transitioning between
242 inner and outer rexen */
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243 CHECKPOINT cp; /* remember current savestack indexes */
244 CHECKPOINT lastcp;
40a82448 245 regnode *B; /* the node following us */
6bda09f9 246 U32 close_paren; /* which close bracket is our end */
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247 } eval;
248
249 struct {
c476f425 250 /* this first element must match u.yes */
262b90c4 251 struct regmatch_state *prev_yes_state;
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252 struct regmatch_state *prev_curlyx; /* previous cur_curlyx */
253 CHECKPOINT cp; /* remember current savestack index */
254 bool minmod;
a0374537 255 int parenfloor;/* how far back to strip paren data */
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256 int min; /* the minimal number of A's to match */
257 int max; /* the maximal number of A's to match */
258 regnode *A, *B; /* the nodes corresponding to /A*B/ */
259
260 /* these two are modified by WHILEM */
261 int count; /* how many instances of A we've matched */
262 char *lastloc;/* where previous A matched (0-len detect) */
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263 } curlyx;
264
265 struct {
c476f425 266 /* this first element must match u.yes */
262b90c4 267 struct regmatch_state *prev_yes_state;
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268 struct regmatch_state *save_curlyx;
269 CHECKPOINT cp; /* remember current savestack indexes */
270 CHECKPOINT lastcp;
271 char *save_lastloc; /* previous curlyx.lastloc */
272 I32 cache_offset;
273 I32 cache_mask;
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274 } whilem;
275
276 struct {
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277 I32 lastparen;
278 regnode *next_branch; /* next branch node */
279 CHECKPOINT cp;
280 } branch;
281
282 struct {
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283 /* this first element must match u.yes */
284 struct regmatch_state *prev_yes_state;
e822a8b4 285 I32 c1, c2; /* case fold search */
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286 CHECKPOINT cp;
287 I32 alen; /* length of first-matched A string */
288 I32 count;
0cadcf80 289 bool minmod;
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290 regnode *A, *B; /* the nodes corresponding to /A*B/ */
291 regnode *me; /* the curlym node */
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292 } curlym;
293
294 struct {
295 I32 paren;
c255a977 296 CHECKPOINT cp;
e822a8b4 297 I32 c1, c2; /* case fold search */
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298 char *maxpos; /* highest possible point in string to match */
299 char *oldloc; /* the previous locinput */
e822a8b4 300 int count;
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301 int min, max; /* {m,n} */
302 regnode *A, *B; /* the nodes corresponding to /A*B/ */
303 } curly; /* and CURLYN/PLUS/STAR */
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304
305 struct {
306 /* this first element must match u.yes */
307 struct regmatch_state *prev_yes_state;
308 I32 wanted;
24d3c4a9 309 I32 logical; /* saved copy of 'logical' var */
40a82448 310 regnode *me; /* the IFMATCH/SUSPEND/UNLESSM node */
dad79028 311 } ifmatch; /* and SUSPEND/UNLESSM */
d8319b27 312 } u;
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313} regmatch_state;
314
315/* how many regmatch_state structs to allocate as a single slab.
316 * We do it in 4K blocks for efficiency. The "3" is 2 for the next/prev
317 * pointers, plus 1 for any mythical malloc overhead. */
318
319#define PERL_REGMATCH_SLAB_SLOTS \
320 ((4096 - 3 * sizeof (void*)) / sizeof(regmatch_state))
321
322typedef struct regmatch_slab {
323 regmatch_state states[PERL_REGMATCH_SLAB_SLOTS];
324 struct regmatch_slab *prev, *next;
325} regmatch_slab;
1ade1aa1 326
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327#define PL_reg_flags PL_reg_state.re_state_reg_flags
328#define PL_bostr PL_reg_state.re_state_bostr
329#define PL_reginput PL_reg_state.re_state_reginput
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330#define PL_regeol PL_reg_state.re_state_regeol
331#define PL_regstartp PL_reg_state.re_state_regstartp
332#define PL_regendp PL_reg_state.re_state_regendp
333#define PL_reglastparen PL_reg_state.re_state_reglastparen
334#define PL_reglastcloseparen PL_reg_state.re_state_reglastcloseparen
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335#define PL_reg_start_tmp PL_reg_state.re_state_reg_start_tmp
336#define PL_reg_start_tmpl PL_reg_state.re_state_reg_start_tmpl
337#define PL_reg_eval_set PL_reg_state.re_state_reg_eval_set
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338#define PL_reg_match_utf8 PL_reg_state.re_state_reg_match_utf8
339#define PL_reg_magic PL_reg_state.re_state_reg_magic
340#define PL_reg_oldpos PL_reg_state.re_state_reg_oldpos
341#define PL_reg_oldcurpm PL_reg_state.re_state_reg_oldcurpm
342#define PL_reg_curpm PL_reg_state.re_state_reg_curpm
343#define PL_reg_oldsaved PL_reg_state.re_state_reg_oldsaved
344#define PL_reg_oldsavedlen PL_reg_state.re_state_reg_oldsavedlen
345#define PL_reg_maxiter PL_reg_state.re_state_reg_maxiter
346#define PL_reg_leftiter PL_reg_state.re_state_reg_leftiter
347#define PL_reg_poscache PL_reg_state.re_state_reg_poscache
348#define PL_reg_poscache_size PL_reg_state.re_state_reg_poscache_size
349#define PL_regsize PL_reg_state.re_state_regsize
350#define PL_reg_starttry PL_reg_state.re_state_reg_starttry
351#define PL_nrs PL_reg_state.re_state_nrs
352
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353struct re_save_state {
354 U32 re_state_reg_flags; /* from regexec.c */
355 char *re_state_bostr;
356 char *re_state_reginput; /* String-input pointer. */
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357 char *re_state_regeol; /* End of input, for $ check. */
358 I32 *re_state_regstartp; /* Pointer to startp array. */
359 I32 *re_state_regendp; /* Ditto for endp. */
360 U32 *re_state_reglastparen; /* Similarly for lastparen. */
361 U32 *re_state_reglastcloseparen; /* Similarly for lastcloseparen. */
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362 char **re_state_reg_start_tmp; /* from regexec.c */
363 U32 re_state_reg_start_tmpl; /* from regexec.c */
364 I32 re_state_reg_eval_set; /* from regexec.c */
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365 bool re_state_reg_match_utf8; /* from regexec.c */
366 MAGIC *re_state_reg_magic; /* from regexec.c */
367 I32 re_state_reg_oldpos; /* from regexec.c */
368 PMOP *re_state_reg_oldcurpm; /* from regexec.c */
369 PMOP *re_state_reg_curpm; /* from regexec.c */
370 char *re_state_reg_oldsaved; /* old saved substr during match */
371 STRLEN re_state_reg_oldsavedlen; /* old length of saved substr during match */
372 I32 re_state_reg_maxiter; /* max wait until caching pos */
373 I32 re_state_reg_leftiter; /* wait until caching pos */
374 char *re_state_reg_poscache; /* cache of pos of WHILEM */
375 STRLEN re_state_reg_poscache_size; /* size of pos cache of WHILEM */
376 I32 re_state_regsize; /* from regexec.c */
377 char *re_state_reg_starttry; /* from regexec.c */
378#ifdef PERL_OLD_COPY_ON_WRITE
46ab3289 379 SV *re_state_nrs; /* was placeholder: unused since 5.8.0 (5.7.2 patch #12027 for bug ID 20010815.012). Used to save rx->saved_copy */
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380#endif
381};
382
383#define SAVESTACK_ALLOC_FOR_RE_SAVE_STATE \
384 (1 + ((sizeof(struct re_save_state) - 1) / sizeof(*PL_savestack)))
385/*
386 * Local variables:
387 * c-indentation-style: bsd
388 * c-basic-offset: 4
389 * indent-tabs-mode: t
390 * End:
391 *
392 * ex: set ts=8 sts=4 sw=4 noet:
393 */