xref: /openbsd-src/gnu/usr.bin/perl/regcomp.h (revision fc405d53b73a2d73393cb97f684863d17b583e38)
1 /*    regcomp.h
2  *
3  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4  *    2000, 2001, 2002, 2003, 2005, 2006, 2007, by Larry Wall and others
5  *
6  *    You may distribute under the terms of either the GNU General Public
7  *    License or the Artistic License, as specified in the README file.
8  *
9  */
10 
11 #if ! defined(PERL_REGCOMP_H_) && (   defined(PERL_CORE)            \
12                                    || defined(PERL_EXT_RE_BUILD))
13 #define PERL_REGCOMP_H_
14 
15 #include "regcharclass.h"
16 
17 /* Convert branch sequences to more efficient trie ops? */
18 #define PERL_ENABLE_TRIE_OPTIMISATION 1
19 
20 /* Be really aggressive about optimising patterns with trie sequences? */
21 #define PERL_ENABLE_EXTENDED_TRIE_OPTIMISATION 1
22 
23 /* Should the optimiser take positive assertions into account? */
24 #define PERL_ENABLE_POSITIVE_ASSERTION_STUDY 0
25 
26 /* Not for production use: */
27 #define PERL_ENABLE_EXPERIMENTAL_REGEX_OPTIMISATIONS 0
28 
29 /*
30  * Structure for regexp "program".  This is essentially a linear encoding
31  * of a nondeterministic finite-state machine (aka syntax charts or
32  * "railroad normal form" in parsing technology).  Each node is an opcode
33  * plus a "next" pointer, possibly plus an operand.  "Next" pointers of
34  * all nodes except BRANCH implement concatenation; a "next" pointer with
35  * a BRANCH on both ends of it is connecting two alternatives.  (Here we
36  * have one of the subtle syntax dependencies:  an individual BRANCH (as
37  * opposed to a collection of them) is never concatenated with anything
38  * because of operator precedence.)  The operand of some types of node is
39  * a literal string; for others, it is a node leading into a sub-FSM.  In
40  * particular, the operand of a BRANCH node is the first node of the branch.
41  * (NB this is *not* a tree structure:  the tail of the branch connects
42  * to the thing following the set of BRANCHes.)  The opcodes are defined
43  * in regnodes.h which is generated from regcomp.sym by regcomp.pl.
44  */
45 
46 /*
47  * A node is one char of opcode followed by two chars of "next" pointer.
48  * "Next" pointers are stored as two 8-bit pieces, high order first.  The
49  * value is a positive offset from the opcode of the node containing it.
50  * An operand, if any, simply follows the node.  (Note that much of the
51  * code generation knows about this implicit relationship.)
52  *
53  * Using two bytes for the "next" pointer is vast overkill for most things,
54  * but allows patterns to get big without disasters.
55  *
56  * [The "next" pointer is always aligned on an even
57  * boundary, and reads the offset directly as a short.]
58  */
59 
60 /* This is the stuff that used to live in regexp.h that was truly
61    private to the engine itself. It now lives here. */
62 
63 typedef struct regexp_internal {
64         regnode *regstclass;    /* Optional startclass as identified or constructed
65                                    by the optimiser */
66         struct reg_data *data;	/* Additional miscellaneous data used by the program.
67                                    Used to make it easier to clone and free arbitrary
68                                    data that the regops need. Often the ARG field of
69                                    a regop is an index into this structure. NOTE the
70                                    0th element of this structure is NEVER used and is
71                                    strictly reserved for internal purposes. */
72         struct reg_code_blocks *code_blocks;/* positions of literal (?{}) */
73         U32 proglen;            /* size of the compiled program in regnodes */
74         U32 name_list_idx;      /* Optional data index of an array of paren names,
75                                    only valid when RXp_PAREN_NAMES(prog) is true,
76                                    0 means "no value" like any other index into the
77                                    data array.*/
78         regnode program[1];	/* Unwarranted chumminess with compiler. */
79 } regexp_internal;
80 
81 #define RXi_SET(x,y) (x)->pprivate = (void*)(y)
82 #define RXi_GET(x)   ((regexp_internal *)((x)->pprivate))
83 #define RXi_GET_DECL(r,ri) regexp_internal *ri = RXi_GET(r)
84 /*
85  * Flags stored in regexp->intflags
86  * These are used only internally to the regexp engine
87  *
88  * See regexp.h for flags used externally to the regexp engine
89  */
90 #define RXp_INTFLAGS(rx)        ((rx)->intflags)
91 #define RX_INTFLAGS(prog)        RXp_INTFLAGS(ReANY(prog))
92 
93 #define PREGf_SKIP		0x00000001
94 #define PREGf_IMPLICIT		0x00000002 /* Converted .* to ^.* */
95 #define PREGf_NAUGHTY		0x00000004 /* how exponential is this pattern? */
96 #define PREGf_VERBARG_SEEN	0x00000008
97 #define PREGf_CUTGROUP_SEEN	0x00000010
98 #define PREGf_USE_RE_EVAL	0x00000020 /* compiled with "use re 'eval'" */
99 /* these used to be extflags, but are now intflags */
100 #define PREGf_NOSCAN            0x00000040
101                                 /* spare */
102 #define PREGf_GPOS_SEEN         0x00000100
103 #define PREGf_GPOS_FLOAT        0x00000200
104 
105 #define PREGf_ANCH_MBOL         0x00000400
106 #define PREGf_ANCH_SBOL         0x00000800
107 #define PREGf_ANCH_GPOS         0x00001000
108 #define PREGf_RECURSE_SEEN      0x00002000
109 
110 #define PREGf_ANCH              \
111     ( PREGf_ANCH_SBOL | PREGf_ANCH_GPOS | PREGf_ANCH_MBOL )
112 
113 /* this is where the old regcomp.h started */
114 
115 
116 /* Define the various regnode structures. These all should be a multiple
117  * of 32 bits large, and they should by and large correspond with each other
118  * in terms of naming, etc. Things can and will break in subtle ways if you
119  * change things without care. If you look at regexp.h you will see it
120  * contains this:
121  *
122  * struct regnode {
123  *   U8  flags;
124  *   U8  type;
125  *   U16 next_off;
126  * };
127  *
128  * This structure is the base unit of elements in the regexp program. When
129  * we increment our way through the program we increment by the size of this
130  * structure, and in all cases where regnode sizing is considered it is in
131  * units of this structure.
132  *
133  * This implies that no regnode style structure should contain 64 bit
134  * aligned members. Since the base regnode is 32 bits any member might
135  * not be 64 bit aligned no matter how you might try to pad out the
136  * struct itself (the regnode_ssc is special in this regard as it is
137  * never used in a program directly). If you want to store 64 bit
138  * members you need to store them specially. The struct regnode_p and the
139  * ARGp() and ARGp_SET() macros and related inline functions provide an example
140  * solution. Note they deal with a slightly more complicated problem than simple
141  * alignment, as pointers may be 32 bits or 64 bits depending on platform,
142  * but they illustrate the pattern to follow if you want to put a 64 bit value
143  * into a regnode.
144 
145  * NOTE: Ideally we do not put pointers into the regnodes in a program. Instead
146  * we put them in the "data" part of the regexp structure and store the index into
147  * the data in the pointers in the regnode. This allows the pointer to be handled
148  * properly during clone/free operations (eg refcount bookkeeping). See S_add_data(),
149  * Perl_regdupe_internal(), Perl_regfree_internal() in regcomp.c for how the data
150  * array can be used, the letters 'arsSu' all refer to different types of SV that
151  * we already have support for in the data array.
152  */
153 
154 struct regnode_string {
155     U8	str_len;
156     U8  type;
157     U16 next_off;
158     char string[1];
159 };
160 
161 struct regnode_lstring { /* Constructed this way to keep the string aligned. */
162     U8	flags;
163     U8  type;
164     U16 next_off;
165     U32 str_len;    /* Only 18 bits allowed before would overflow 'next_off' */
166     char string[1];
167 };
168 
169 struct regnode_anyofhs { /* Constructed this way to keep the string aligned. */
170     U8	str_len;
171     U8  type;
172     U16 next_off;
173     U32 arg1;                           /* set by set_ANYOF_arg() */
174     char string[1];
175 };
176 
177 /* Argument bearing node - workhorse,
178    arg1 is often for the data field */
179 struct regnode_1 {
180     U8	flags;
181     U8  type;
182     U16 next_off;
183     U32 arg1;
184 };
185 
186 /* Node whose argument is 'SV *'.  This needs to be used very carefully in
187  * situations where pointers won't become invalid because of, say re-mallocs.
188  *
189  * Note that this regnode type is problematic and should not be used or copied
190  * and will be removed in the future. Pointers should be stored in the data[]
191  * array and an index into the data array stored in the regnode, which allows the
192  * pointers to be handled properly during clone/free operations on the regexp
193  * data structure. As a byproduct it also saves space, often we use a 16 bit
194  * member to store indexes into the data[] array.
195  *
196  * Also note that the weird storage here is because regnodes are 32 bit aligned,
197  * which means we cannot have a 64 bit aligned member. To make things more annoying
198  * the size of a pointer may vary by platform. Thus we use a character array, and
199  * then use inline functions to copy the data in or out.
200  * */
201 struct regnode_p {
202     U8	flags;
203     U8  type;
204     U16 next_off;
205     char arg1_sv_ptr_bytes[sizeof(SV *)];
206 };
207 
208 /* Similar to a regnode_1 but with an extra signed argument */
209 struct regnode_2L {
210     U8	flags;
211     U8  type;
212     U16 next_off;
213     U32 arg1;
214     I32 arg2;
215 };
216 
217 /* 'Two field' -- Two 16 bit unsigned args */
218 struct regnode_2 {
219     U8	flags;
220     U8  type;
221     U16 next_off;
222     U16 arg1;
223     U16 arg2;
224 };
225 
226 #define ANYOF_BITMAP_SIZE	(NUM_ANYOF_CODE_POINTS / 8)   /* 8 bits/Byte */
227 
228 /* Note that these form structs which are supersets of the next smaller one, by
229  * appending fields.  Alignment problems can occur if one of those optional
230  * fields requires stricter alignment than the base struct.  And formal
231  * parameters that can really be two or more of the structs should be
232  * declared as the smallest one it could be.  See commit message for
233  * 7dcac5f6a5195002b55c935ee1d67f67e1df280b.  Regnode allocation is done
234  * without regard to alignment, and changing it to would also require changing
235  * the code that inserts and deletes regnodes.  The basic single-argument
236  * regnode has a U32, which is what reganode() allocates as a unit.  Therefore
237  * no field can require stricter alignment than U32. */
238 
239 /* also used by trie */
240 struct regnode_charclass {
241     U8	flags;
242     U8  type;
243     U16 next_off;
244     U32 arg1;                           /* set by set_ANYOF_arg() */
245     char bitmap[ANYOF_BITMAP_SIZE];	/* only compile-time */
246 };
247 
248 /* has runtime (locale) \d, \w, ..., [:posix:] classes */
249 struct regnode_charclass_posixl {
250     U8	flags;                      /* ANYOF_MATCHES_POSIXL bit must go here */
251     U8  type;
252     U16 next_off;
253     U32 arg1;
254     char bitmap[ANYOF_BITMAP_SIZE];		/* both compile-time ... */
255     U32 classflags;	                        /* and run-time */
256 };
257 
258 /* A synthetic start class (SSC); is a regnode_charclass_posixl_fold, plus an
259  * extra SV*, used only during regex construction and which is not used by the
260  * main machinery in regexec.c and which does not get embedded in the final compiled
261  * regex program.
262  *
263  * Because it does not get embedded it does not have to comply with the alignment
264  * and sizing constraints required for a normal regnode structure: it MAY contain
265  * pointers or members of whatever size needed and the compiler will do the right
266  * thing. (Every other regnode type is 32 bit aligned.)
267  *
268  * Note that the 'next_off' field is unused, as the SSC stands alone, so there is
269  * never a next node.
270  */
271 struct regnode_ssc {
272     U8	flags;                      /* ANYOF_MATCHES_POSIXL bit must go here */
273     U8  type;
274     U16 next_off;
275     U32 arg1;
276     char bitmap[ANYOF_BITMAP_SIZE];	/* both compile-time ... */
277     U32 classflags;	                /* ... and run-time */
278 
279     /* Auxiliary, only used during construction; NULL afterwards: list of code
280      * points matched */
281     SV* invlist;
282 };
283 
284 /*  We take advantage of 'next_off' not otherwise being used in the SSC by
285  *  actually using it: by setting it to 1.  This allows us to test and
286  *  distinguish between an SSC and other ANYOF node types, as 'next_off' cannot
287  *  otherwise be 1, because it is the offset to the next regnode expressed in
288  *  units of regnodes.  Since an ANYOF node contains extra fields, it adds up
289  *  to 12 regnode units on 32-bit systems, (hence the minimum this can be (if
290  *  not 0) is 11 there.  Even if things get tightly packed on a 64-bit system,
291  *  it still would be more than 1. */
292 #define set_ANYOF_SYNTHETIC(n) STMT_START{ OP(n) = ANYOF;              \
293                                            NEXT_OFF(n) = 1;            \
294                                } STMT_END
295 #define is_ANYOF_SYNTHETIC(n) (PL_regkind[OP(n)] == ANYOF && NEXT_OFF(n) == 1)
296 
297 /* XXX fix this description.
298    Impose a limit of REG_INFTY on various pattern matching operations
299    to limit stack growth and to avoid "infinite" recursions.
300 */
301 /* The default size for REG_INFTY is U16_MAX, which is the same as
302    USHORT_MAX (see perl.h).  Unfortunately U16 isn't necessarily 16 bits
303    (see handy.h).  On the Cray C90, sizeof(short)==4 and hence U16_MAX is
304    ((1<<32)-1), while on the Cray T90, sizeof(short)==8 and U16_MAX is
305    ((1<<64)-1).  To limit stack growth to reasonable sizes, supply a
306    smaller default.
307         --Andy Dougherty  11 June 1998
308 */
309 #if SHORTSIZE > 2
310 #  ifndef REG_INFTY
311 #    define REG_INFTY  nBIT_UMAX(16)
312 #  endif
313 #endif
314 
315 #ifndef REG_INFTY
316 #  define REG_INFTY U16_MAX
317 #endif
318 
319 #define ARG_VALUE(arg) (arg)
320 #define ARG__SET(arg,val) ((arg) = (val))
321 
322 #undef ARG
323 #undef ARG1
324 #undef ARG2
325 
326 #define ARG(p) ARG_VALUE(ARG_LOC(p))
327 #define ARGp(p) ARGp_VALUE_inline(p)
328 #define ARG1(p) ARG_VALUE(ARG1_LOC(p))
329 #define ARG2(p) ARG_VALUE(ARG2_LOC(p))
330 #define ARG2L(p) ARG_VALUE(ARG2L_LOC(p))
331 
332 #define ARG_SET(p, val) ARG__SET(ARG_LOC(p), (val))
333 #define ARG1_SET(p, val) ARG__SET(ARG1_LOC(p), (val))
334 #define ARG2_SET(p, val) ARG__SET(ARG2_LOC(p), (val))
335 #define ARG2L_SET(p, val) ARG__SET(ARG2L_LOC(p), (val))
336 #define ARGp_SET(p, val) ARGp_SET_inline((p),(val))
337 
338 #undef NEXT_OFF
339 #undef NODE_ALIGN
340 
341 #define NEXT_OFF(p) ((p)->next_off)
342 #define NODE_ALIGN(node)
343 /* the following define was set to 0xde in 075abff3
344  * as part of some linting logic. I have set it to 0
345  * as otherwise in every place where we /might/ set flags
346  * we have to set it 0 explicitly, which duplicates
347  * assignments and IMO adds an unacceptable level of
348  * surprise to working in the regex engine. If this
349  * is changed from 0 then at the very least make sure
350  * that SBOL for /^/ sets the flags to 0 explicitly.
351  * -- Yves */
352 #define NODE_ALIGN_FILL(node) ((node)->flags = 0)
353 
354 #define SIZE_ALIGN NODE_ALIGN
355 
356 #undef OP
357 #undef OPERAND
358 #undef STRING
359 
360 #define	OP(p)		((p)->type)
361 #define FLAGS(p)	((p)->flags)	/* Caution: Doesn't apply to all      \
362                                            regnode types.  For some, it's the \
363                                            character set of the regnode */
364 #define	STR_LENs(p)	(__ASSERT_(OP(p) != LEXACT && OP(p) != LEXACT_REQ8)  \
365                                     ((struct regnode_string *)p)->str_len)
366 #define	STRINGs(p)	(__ASSERT_(OP(p) != LEXACT && OP(p) != LEXACT_REQ8)  \
367                                     ((struct regnode_string *)p)->string)
368 #define	OPERANDs(p)	STRINGs(p)
369 
370 /* Long strings.  Currently limited to length 18 bits, which handles a 262000
371  * byte string.  The limiting factor is the 16 bit 'next_off' field, which
372  * points to the next regnode, so the furthest away it can be is 2**16.  On
373  * most architectures, regnodes are 2**2 bytes long, so that yields 2**18
374  * bytes.  Should a longer string be desired, we could increase it to 26 bits
375  * fairly easily, by changing this node to have longj type which causes the ARG
376  * field to be used for the link to the next regnode (although code would have
377  * to be changed to account for this), and then use a combination of the flags
378  * and next_off fields for the length.  To get 34 bit length, also change the
379  * node to be an ARG2L, using the second 32 bit field for the length, and not
380  * using the flags nor next_off fields at all.  One could have an llstring node
381  * and even an lllstring type. */
382 #define	STR_LENl(p)	(__ASSERT_(OP(p) == LEXACT || OP(p) == LEXACT_REQ8)  \
383                                     (((struct regnode_lstring *)p)->str_len))
384 #define	STRINGl(p)	(__ASSERT_(OP(p) == LEXACT || OP(p) == LEXACT_REQ8)  \
385                                     (((struct regnode_lstring *)p)->string))
386 #define	OPERANDl(p)	STRINGl(p)
387 
388 #define	STR_LEN(p)	((OP(p) == LEXACT || OP(p) == LEXACT_REQ8)           \
389                                                ? STR_LENl(p) : STR_LENs(p))
390 #define	STRING(p)	((OP(p) == LEXACT || OP(p) == LEXACT_REQ8)           \
391                                                ? STRINGl(p)  : STRINGs(p))
392 #define	OPERAND(p)	STRING(p)
393 
394 /* The number of (smallest) regnode equivalents that a string of length l bytes
395  * occupies */
396 #define STR_SZ(l)	(((l) + sizeof(regnode) - 1) / sizeof(regnode))
397 
398 /* The number of (smallest) regnode equivalents that the EXACTISH node 'p'
399  * occupies */
400 #define NODE_SZ_STR(p)	(STR_SZ(STR_LEN(p)) + 1 + regarglen[(p)->type])
401 
402 #define setSTR_LEN(p,v)                                                     \
403     STMT_START{                                                             \
404         if (OP(p) == LEXACT || OP(p) == LEXACT_REQ8)                        \
405             ((struct regnode_lstring *)(p))->str_len = (v);                 \
406         else                                                                \
407             ((struct regnode_string *)(p))->str_len = (v);                  \
408     } STMT_END
409 
410 #define ANYOFR_BASE_BITS    20
411 #define ANYOFRbase(p)   (ARG(p) & nBIT_MASK(ANYOFR_BASE_BITS))
412 #define ANYOFRdelta(p)  (ARG(p) >> ANYOFR_BASE_BITS)
413 
414 #undef NODE_ALIGN
415 #undef ARG_LOC
416 #undef NEXTOPER
417 #undef PREVOPER
418 
419 #define	NODE_ALIGN(node)
420 #define	ARG_LOC(p)	(((struct regnode_1 *)p)->arg1)
421 #define ARGp_BYTES_LOC(p)  (((struct regnode_p *)p)->arg1_sv_ptr_bytes)
422 #define	ARG1_LOC(p)	(((struct regnode_2 *)p)->arg1)
423 #define	ARG2_LOC(p)	(((struct regnode_2 *)p)->arg2)
424 #define ARG2L_LOC(p)	(((struct regnode_2L *)p)->arg2)
425 
426 #define NODE_STEP_REGNODE	1	/* sizeof(regnode)/sizeof(regnode) */
427 #define EXTRA_STEP_2ARGS	EXTRA_SIZE(struct regnode_2)
428 
429 #define	NEXTOPER(p)	((p) + NODE_STEP_REGNODE)
430 #define	PREVOPER(p)	((p) - NODE_STEP_REGNODE)
431 
432 #define FILL_NODE(offset, op)                                           \
433     STMT_START {                                                        \
434                     OP(REGNODE_p(offset)) = op;                         \
435                     NEXT_OFF(REGNODE_p(offset)) = 0;                    \
436     } STMT_END
437 #define FILL_ADVANCE_NODE(offset, op)                                   \
438     STMT_START {                                                        \
439                     FILL_NODE(offset, op);                              \
440                     (offset)++;                                         \
441     } STMT_END
442 #define FILL_ADVANCE_NODE_ARG(offset, op, arg)                          \
443     STMT_START {                                                        \
444                     ARG_SET(REGNODE_p(offset), arg);                    \
445                     FILL_ADVANCE_NODE(offset, op);                      \
446                     /* This is used generically for other operations    \
447                      * that have a longer argument */                   \
448                     (offset) += regarglen[op];                          \
449     } STMT_END
450 #define FILL_ADVANCE_NODE_ARGp(offset, op, arg)                          \
451     STMT_START {                                                        \
452                     ARGp_SET(REGNODE_p(offset), arg);                    \
453                     FILL_ADVANCE_NODE(offset, op);                      \
454                     (offset) += regarglen[op];                          \
455     } STMT_END
456 #define FILL_ADVANCE_NODE_2L_ARG(offset, op, arg1, arg2)                \
457     STMT_START {                                                        \
458                     ARG_SET(REGNODE_p(offset), arg1);                   \
459                     ARG2L_SET(REGNODE_p(offset), arg2);                 \
460                     FILL_ADVANCE_NODE(offset, op);                      \
461                     (offset) += 2;                                      \
462     } STMT_END
463 
464 /* define these after we define the normal macros, so we can use
465  * ARGp_BYTES_LOC(n) */
466 
467 static inline SV *
468 ARGp_VALUE_inline(struct regnode *node) {
469     SV *ptr;
470     memcpy(&ptr, ARGp_BYTES_LOC(node), sizeof(ptr));
471 
472     return ptr;
473 }
474 
475 static inline void
476 ARGp_SET_inline(struct regnode *node, SV *ptr) {
477     memcpy(ARGp_BYTES_LOC(node), &ptr, sizeof(ptr));
478 }
479 
480 #define REG_MAGIC 0234
481 
482 /* An ANYOF node is basically a bitmap with the index being a code point.  If
483  * the bit for that code point is 1, the code point matches;  if 0, it doesn't
484  * match (complemented if inverted).  There is an additional mechanism to deal
485  * with cases where the bitmap is insufficient in and of itself.  This #define
486  * indicates if the bitmap does fully represent what this ANYOF node can match.
487  * The ARG is set to this special value (since 0, 1, ... are legal, but will
488  * never reach this high). */
489 #define ANYOF_ONLY_HAS_BITMAP	((U32) -1)
490 
491 /* When the bitmap isn't completely sufficient for handling the ANYOF node,
492  * flags (in node->flags of the ANYOF node) get set to indicate this.  These
493  * are perennially in short supply.  Beyond several cases where warnings need
494  * to be raised under certain circumstances, currently, there are six cases
495  * where the bitmap alone isn't sufficient.  We could use six flags to
496  * represent the 6 cases, but to save flags bits, we play some games.  The
497  * cases are:
498  *
499  *  1)  The bitmap has a compiled-in very finite size.  So something else needs
500  *      to be used to specify if a code point that is too large for the bitmap
501  *      actually matches.  The mechanism currently is an inversion
502  *      list.  ANYOF_ONLY_HAS_BITMAP, described above, being TRUE indicates
503  *      there are no matches of too-large code points.  But if it is FALSE,
504  *      then almost certainly there are matches too large for the bitmap.  (The
505  *      other cases, described below, either imply this one or are extremely
506  *      rare in practice.)  So we can just assume that a too-large code point
507  *      will need something beyond the bitmap if ANYOF_ONLY_HAS_BITMAP is
508  *      FALSE, instead of having a separate flag for this.
509  *  2)  A subset of item 1) is if all possible code points outside the bitmap
510  *      match.  This is a common occurrence when the class is complemented,
511  *      like /[^ij]/.  Therefore a bit is reserved to indicate this,
512  *      rather than having an inversion list created,
513  *      ANYOF_MATCHES_ALL_ABOVE_BITMAP.
514  *  3)  Under /d rules, it can happen that code points that are in the upper
515  *      latin1 range (\x80-\xFF or their equivalents on EBCDIC platforms) match
516  *      only if the runtime target string being matched against is UTF-8.  For
517  *      example /[\w[:punct:]]/d.  This happens only for posix classes (with a
518  *      couple of exceptions, like \d where it doesn't happen), and all such
519  *      ones also have above-bitmap matches.  Thus, 3) implies 1) as well.
520  *      Note that /d rules are no longer encouraged; 'use 5.14' or higher
521  *      deselects them.  But a flag is required so that they can be properly
522  *      handled.  But it can be a shared flag: see 5) below.
523  *  4)  Also under /d rules, something like /[\Wfoo]/ will match everything in
524  *      the \x80-\xFF range, unless the string being matched against is UTF-8.
525  *      An inversion list could be created for this case, but this is
526  *      relatively common, and it turns out that it's all or nothing:  if any
527  *      one of these code points matches, they all do.  Hence a single bit
528  *      suffices.  We use a shared flag that doesn't take up space by itself:
529  *      ANYOF_SHARED_d_MATCHES_ALL_NON_UTF8_NON_ASCII_non_d_WARN_SUPER.  This
530  *      also implies 1), with one exception: [:^cntrl:].
531  *  5)  A user-defined \p{} property may not have been defined by the time the
532  *      regex is compiled.  In this case, we don't know until runtime what it
533  *      will match, so we have to assume it could match anything, including
534  *      code points that ordinarily would be in the bitmap.  A flag bit is
535  *      necessary to indicate this, though it can be shared with the item 3)
536  *      flag, as that only occurs under /d, and this only occurs under non-d.
537  *      This case is quite uncommon in the field, and the /(?[ ...])/ construct
538  *      is a better way to accomplish what this feature does.  This case also
539  *      implies 1).
540  *      ANYOF_SHARED_d_UPPER_LATIN1_UTF8_STRING_MATCHES_non_d_RUNTIME_USER_PROP
541  *      is the shared flag.
542  *  6)  /[foo]/il may have folds that are only valid if the runtime locale is a
543  *      UTF-8 one.  These are quite rare, so it would be good to avoid the
544  *      expense of looking for them.  But /l matching is slow anyway, and we've
545  *      traditionally not worried too much about its performance.  And this
546  *      condition requires the ANYOFL_FOLD flag to be set, so testing for
547  *      that flag would be sufficient to rule out most cases of this.  So it is
548  *      unclear if this should have a flag or not.  But, this flag can be
549  *      shared with another, so it doesn't occupy extra space.
550  *
551  * At the moment, there is one spare bit, but this could be increased by
552  * various tricks:
553  *
554  * If just one more bit is needed, as of this writing it seems to khw that the
555  * best choice would be to make ANYOF_MATCHES_ALL_ABOVE_BITMAP not a flag, but
556  * something like
557  *
558  *      #define ANYOF_MATCHES_ALL_ABOVE_BITMAP      ((U32) -2)
559  *
560  * and access it through the ARG like ANYOF_ONLY_HAS_BITMAP is.  This flag is
561  * used by all ANYOF node types, and it could be used to avoid calling the
562  * handler function, as the macro REGINCLASS in regexec.c does now for other
563  * cases.
564  *
565  * Another possibility is based on the fact that ANYOF_MATCHES_POSIXL is
566  * redundant with the node type ANYOFPOSIXL.  That flag could be removed, but
567  * at the expense of extra code in regexec.c.  The flag has been retained
568  * because it allows us to see if we need to call reginclass, or just use the
569  * bitmap in one test.
570  *
571  * If this is done, an extension would be to make all ANYOFL nodes contain the
572  * extra 32 bits that ANYOFPOSIXL ones do.  The posix flags only occupy 30
573  * bits, so the ANYOFL_SHARED_UTF8_LOCALE_fold_HAS_MATCHES_nonfold_REQD flags
574  * and ANYOFL_FOLD could be moved to that extra space, but it would mean extra
575  * instructions, as there are currently places in the code that assume those
576  * two bits are zero.
577  *
578  * All told, 5 bits could be available for other uses if all of the above were
579  * done.
580  *
581  * Some flags are not used in synthetic start class (SSC) nodes, so could be
582  * shared should new flags be needed for SSCs, like SSC_MATCHES_EMPTY_STRING
583  * now. */
584 
585 /* If this is set, the result of the match should be complemented.  regexec.c
586  * is expecting this to be in the low bit.  Never in an SSC */
587 #define ANYOF_INVERT		                0x01
588 
589 /* For the SSC node only, which cannot be inverted, so is shared with that bit.
590  * This is used only during regex compilation. */
591 #define SSC_MATCHES_EMPTY_STRING                ANYOF_INVERT
592 
593 /* Set if this is a regnode_charclass_posixl vs a regnode_charclass.  This
594  * is used for runtime \d, \w, [:posix:], ..., which are used only in locale
595  * and the optimizer's synthetic start class.  Non-locale \d, etc are resolved
596  * at compile-time.  Only set under /l; can be in SSC */
597 #define ANYOF_MATCHES_POSIXL                    0x02
598 
599 /* The fold is calculated and stored in the bitmap where possible at compile
600  * time.  However under locale, the actual folding varies depending on
601  * what the locale is at the time of execution, so it has to be deferred until
602  * then.  Only set under /l; never in an SSC  */
603 #define ANYOFL_FOLD                             0x04
604 
605 /* Shared bit set only with ANYOFL and SSC nodes:
606  *    If ANYOFL_FOLD is set, this flag indicates there are potential matches
607  *      valid only if the locale is a UTF-8 one.
608  *    If ANYOFL_FOLD is NOT set, this flag means to warn if the runtime locale
609  *       isn't a UTF-8 one (and the generated node assumes a UTF-8 locale).
610  *       None of INVERT, POSIXL,
611  *       ANYOF_SHARED_d_UPPER_LATIN1_UTF8_STRING_MATCHES_non_d_RUNTIME_USER_PROP
612  *       can be set.  */
613 #define ANYOFL_SHARED_UTF8_LOCALE_fold_HAS_MATCHES_nonfold_REQD        0x08
614 
615 /* Convenience macros for teasing apart the meanings when reading the above bit
616  * */
617 #define ANYOFL_SOME_FOLDS_ONLY_IN_UTF8_LOCALE(flags)                        \
618     ((flags & ( ANYOFL_FOLD /* Both bits are set */                         \
619                |ANYOFL_SHARED_UTF8_LOCALE_fold_HAS_MATCHES_nonfold_REQD))   \
620              == ( ANYOFL_FOLD                                               \
621                  |ANYOFL_SHARED_UTF8_LOCALE_fold_HAS_MATCHES_nonfold_REQD))
622 
623 #define  ANYOFL_UTF8_LOCALE_REQD(flags)                                     \
624     ((flags & ( ANYOFL_FOLD /* Only REQD bit is set */                      \
625                |ANYOFL_SHARED_UTF8_LOCALE_fold_HAS_MATCHES_nonfold_REQD))   \
626              == ANYOFL_SHARED_UTF8_LOCALE_fold_HAS_MATCHES_nonfold_REQD)
627 
628 /* Spare: Be sure to change ANYOF_FLAGS_ALL if this gets used  0x10 */
629 
630 /* If set, the node matches every code point NUM_ANYOF_CODE_POINTS and above.
631  * Can be in an SSC */
632 #define ANYOF_MATCHES_ALL_ABOVE_BITMAP          0x20
633 
634 /* Shared bit:
635  *      Under /d it means the ANYOFD node matches more things if the target
636  *          string is encoded in UTF-8; any such things will be non-ASCII,
637  *          characters that are < 256, and can be accessed via the inversion
638  *          list.
639  *      When not under /d, it means the ANYOF node contains a user-defined
640  *      property that wasn't yet defined at the time the regex was compiled,
641  *      and so must be looked up at runtime, by creating an inversion list.
642  * (These uses are mutually exclusive because a user-defined property is
643  * specified by \p{}, and \p{} implies /u which deselects /d).  The long macro
644  * name is to make sure that you are cautioned about its shared nature.  Only
645  * the non-/d meaning can be in an SSC */
646 #define ANYOF_SHARED_d_UPPER_LATIN1_UTF8_STRING_MATCHES_non_d_RUNTIME_USER_PROP  0x40
647 
648 /* Shared bit:
649  *      Under /d it means the ANYOFD node matches all non-ASCII Latin1
650  *          characters when the target string is not in utf8.
651  *      When not under /d, it means the ANYOF node should raise a warning if
652  *          matching against an above-Unicode code point.
653  * (These uses are mutually exclusive because the warning requires a \p{}, and
654  * \p{} implies /u which deselects /d).  An SSC node only has this bit set if
655  * what is meant is the warning.  The long macro name is to make sure that you
656  * are cautioned about its shared nature */
657 #define ANYOF_SHARED_d_MATCHES_ALL_NON_UTF8_NON_ASCII_non_d_WARN_SUPER 0x80
658 
659 #define ANYOF_FLAGS_ALL		((U8) ~0x10)
660 
661 #define ANYOF_LOCALE_FLAGS (ANYOFL_FOLD | ANYOF_MATCHES_POSIXL)
662 
663 /* These are the flags that apply to both regular ANYOF nodes and synthetic
664  * start class nodes during construction of the SSC.  During finalization of
665  * the SSC, other of the flags may get added to it */
666 #define ANYOF_COMMON_FLAGS      0
667 
668 /* Character classes for node->classflags of ANYOF */
669 /* Should be synchronized with a table in regprop() */
670 /* 2n should be the normal one, paired with its complement at 2n+1 */
671 
672 #define ANYOF_ALPHA    ((_CC_ALPHA) * 2)
673 #define ANYOF_NALPHA   ((ANYOF_ALPHA) + 1)
674 #define ANYOF_ALPHANUMERIC   ((_CC_ALPHANUMERIC) * 2)    /* [[:alnum:]] isalnum(3), utf8::IsAlnum */
675 #define ANYOF_NALPHANUMERIC  ((ANYOF_ALPHANUMERIC) + 1)
676 #define ANYOF_ASCII    ((_CC_ASCII) * 2)
677 #define ANYOF_NASCII   ((ANYOF_ASCII) + 1)
678 #define ANYOF_BLANK    ((_CC_BLANK) * 2)     /* GNU extension: space and tab: non-vertical space */
679 #define ANYOF_NBLANK   ((ANYOF_BLANK) + 1)
680 #define ANYOF_CASED    ((_CC_CASED) * 2)    /* Pseudo class for [:lower:] or
681                                                [:upper:] under /i */
682 #define ANYOF_NCASED   ((ANYOF_CASED) + 1)
683 #define ANYOF_CNTRL    ((_CC_CNTRL) * 2)
684 #define ANYOF_NCNTRL   ((ANYOF_CNTRL) + 1)
685 #define ANYOF_DIGIT    ((_CC_DIGIT) * 2)     /* \d */
686 #define ANYOF_NDIGIT   ((ANYOF_DIGIT) + 1)
687 #define ANYOF_GRAPH    ((_CC_GRAPH) * 2)
688 #define ANYOF_NGRAPH   ((ANYOF_GRAPH) + 1)
689 #define ANYOF_LOWER    ((_CC_LOWER) * 2)
690 #define ANYOF_NLOWER   ((ANYOF_LOWER) + 1)
691 #define ANYOF_PRINT    ((_CC_PRINT) * 2)
692 #define ANYOF_NPRINT   ((ANYOF_PRINT) + 1)
693 #define ANYOF_PUNCT    ((_CC_PUNCT) * 2)
694 #define ANYOF_NPUNCT   ((ANYOF_PUNCT) + 1)
695 #define ANYOF_SPACE    ((_CC_SPACE) * 2)     /* \s */
696 #define ANYOF_NSPACE   ((ANYOF_SPACE) + 1)
697 #define ANYOF_UPPER    ((_CC_UPPER) * 2)
698 #define ANYOF_NUPPER   ((ANYOF_UPPER) + 1)
699 #define ANYOF_WORDCHAR ((_CC_WORDCHAR) * 2)  /* \w, PL_utf8_alnum, utf8::IsWord, ALNUM */
700 #define ANYOF_NWORDCHAR   ((ANYOF_WORDCHAR) + 1)
701 #define ANYOF_XDIGIT   ((_CC_XDIGIT) * 2)
702 #define ANYOF_NXDIGIT  ((ANYOF_XDIGIT) + 1)
703 
704 /* pseudo classes below this, not stored in the class bitmap, but used as flags
705    during compilation of char classes */
706 
707 #define ANYOF_VERTWS    ((_CC_VERTSPACE) * 2)
708 #define ANYOF_NVERTWS   ((ANYOF_VERTWS)+1)
709 
710 /* It is best if this is the last one, as all above it are stored as bits in a
711  * bitmap, and it isn't part of that bitmap */
712 #if _CC_VERTSPACE != _HIGHEST_REGCOMP_DOT_H_SYNC
713 #   error Problem with handy.h _HIGHEST_REGCOMP_DOT_H_SYNC #define
714 #endif
715 
716 #define ANYOF_POSIXL_MAX (ANYOF_VERTWS) /* So upper loop limit is written:
717                                          *       '< ANYOF_MAX'
718                                          * Hence doesn't include VERTWS, as that
719                                          * is a pseudo class */
720 #define ANYOF_MAX      ANYOF_POSIXL_MAX
721 
722 #if (ANYOF_POSIXL_MAX > 32)   /* Must fit in 32-bit word */
723 #   error Problem with handy.h _CC_foo #defines
724 #endif
725 
726 #define ANYOF_HORIZWS	((ANYOF_POSIXL_MAX)+2) /* = (ANYOF_NVERTWS + 1) */
727 #define ANYOF_NHORIZWS	((ANYOF_POSIXL_MAX)+3)
728 
729 #define ANYOF_UNIPROP   ((ANYOF_POSIXL_MAX)+4)  /* Used to indicate a Unicode
730                                                    property: \p{} or \P{} */
731 
732 /* Backward source code compatibility. */
733 
734 #define ANYOF_ALNUML	 ANYOF_ALNUM
735 #define ANYOF_NALNUML	 ANYOF_NALNUM
736 #define ANYOF_SPACEL	 ANYOF_SPACE
737 #define ANYOF_NSPACEL	 ANYOF_NSPACE
738 #define ANYOF_ALNUM ANYOF_WORDCHAR
739 #define ANYOF_NALNUM ANYOF_NWORDCHAR
740 
741 /* Utility macros for the bitmap and classes of ANYOF */
742 
743 #define ANYOF_FLAGS(p)		((p)->flags)
744 
745 #define ANYOF_BIT(c)		(1U << ((c) & 7))
746 
747 #define ANYOF_POSIXL_BITMAP(p)  (((regnode_charclass_posixl*) (p))->classflags)
748 
749 #define POSIXL_SET(field, c)	((field) |= (1U << (c)))
750 #define ANYOF_POSIXL_SET(p, c)	POSIXL_SET(ANYOF_POSIXL_BITMAP(p), (c))
751 
752 #define POSIXL_CLEAR(field, c) ((field) &= ~ (1U <<(c)))
753 #define ANYOF_POSIXL_CLEAR(p, c) POSIXL_CLEAR(ANYOF_POSIXL_BITMAP(p), (c))
754 
755 #define POSIXL_TEST(field, c)	((field) & (1U << (c)))
756 #define ANYOF_POSIXL_TEST(p, c)	POSIXL_TEST(ANYOF_POSIXL_BITMAP(p), (c))
757 
758 #define POSIXL_ZERO(field)	STMT_START { (field) = 0; } STMT_END
759 #define ANYOF_POSIXL_ZERO(ret)	POSIXL_ZERO(ANYOF_POSIXL_BITMAP(ret))
760 
761 #define ANYOF_POSIXL_SET_TO_BITMAP(p, bits)                                 \
762                 STMT_START { ANYOF_POSIXL_BITMAP(p) = (bits); } STMT_END
763 
764 /* Shifts a bit to get, eg. 0x4000_0000, then subtracts 1 to get 0x3FFF_FFFF */
765 #define ANYOF_POSIXL_SETALL(ret)                                            \
766                 STMT_START {                                                \
767                     ANYOF_POSIXL_BITMAP(ret) = nBIT_MASK(ANYOF_POSIXL_MAX); \
768                 } STMT_END
769 #define ANYOF_CLASS_SETALL(ret) ANYOF_POSIXL_SETALL(ret)
770 
771 #define ANYOF_POSIXL_TEST_ANY_SET(p)                               \
772         ((ANYOF_FLAGS(p) & ANYOF_MATCHES_POSIXL) && ANYOF_POSIXL_BITMAP(p))
773 #define ANYOF_CLASS_TEST_ANY_SET(p) ANYOF_POSIXL_TEST_ANY_SET(p)
774 
775 /* Since an SSC always has this field, we don't have to test for that; nor do
776  * we want to because the bit isn't set for SSC during its construction */
777 #define ANYOF_POSIXL_SSC_TEST_ANY_SET(p)                               \
778                             cBOOL(((regnode_ssc*)(p))->classflags)
779 #define ANYOF_POSIXL_SSC_TEST_ALL_SET(p) /* Are all bits set? */       \
780         (((regnode_ssc*) (p))->classflags                              \
781                                         == nBIT_MASK(ANYOF_POSIXL_MAX))
782 
783 #define ANYOF_POSIXL_TEST_ALL_SET(p)                                   \
784         ((ANYOF_FLAGS(p) & ANYOF_MATCHES_POSIXL)                       \
785          && ANYOF_POSIXL_BITMAP(p) == nBIT_MASK(ANYOF_POSIXL_MAX))
786 
787 #define ANYOF_POSIXL_OR(source, dest) STMT_START { (dest)->classflags |= (source)->classflags ; } STMT_END
788 #define ANYOF_CLASS_OR(source, dest) ANYOF_POSIXL_OR((source), (dest))
789 
790 #define ANYOF_POSIXL_AND(source, dest) STMT_START { (dest)->classflags &= (source)->classflags ; } STMT_END
791 
792 #define ANYOF_BITMAP_ZERO(ret)	Zero(((regnode_charclass*)(ret))->bitmap, ANYOF_BITMAP_SIZE, char)
793 #define ANYOF_BITMAP(p)		((regnode_charclass*)(p))->bitmap
794 #define ANYOF_BITMAP_BYTE(p, c)	BITMAP_BYTE(ANYOF_BITMAP(p), c)
795 #define ANYOF_BITMAP_SET(p, c)	(ANYOF_BITMAP_BYTE(p, c) |=  ANYOF_BIT(c))
796 #define ANYOF_BITMAP_CLEAR(p,c)	(ANYOF_BITMAP_BYTE(p, c) &= ~ANYOF_BIT(c))
797 #define ANYOF_BITMAP_TEST(p, c)	cBOOL(ANYOF_BITMAP_BYTE(p, c) &   ANYOF_BIT(c))
798 
799 #define ANYOF_BITMAP_SETALL(p)		\
800         memset (ANYOF_BITMAP(p), 255, ANYOF_BITMAP_SIZE)
801 #define ANYOF_BITMAP_CLEARALL(p)	\
802         Zero (ANYOF_BITMAP(p), ANYOF_BITMAP_SIZE)
803 
804 /*
805  * Utility definitions.
806  */
807 #ifndef CHARMASK
808 #  define UCHARAT(p)	((int)*(const U8*)(p))
809 #else
810 #  define UCHARAT(p)	((int)*(p)&CHARMASK)
811 #endif
812 
813 /* Number of regnode equivalents that 'guy' occupies beyond the size of the
814  * smallest regnode. */
815 #define EXTRA_SIZE(guy) ((sizeof(guy)-1)/sizeof(struct regnode))
816 
817 #define REG_ZERO_LEN_SEEN                   0x00000001
818 #define REG_LOOKBEHIND_SEEN                 0x00000002
819 /* add a short form alias to keep the line length police happy */
820 #define REG_LB_SEEN                         REG_LOOKBEHIND_SEEN
821 #define REG_GPOS_SEEN                       0x00000004
822 /* spare */
823 #define REG_RECURSE_SEEN                    0x00000020
824 #define REG_TOP_LEVEL_BRANCHES_SEEN         0x00000040
825 #define REG_VERBARG_SEEN                    0x00000080
826 #define REG_CUTGROUP_SEEN                   0x00000100
827 #define REG_RUN_ON_COMMENT_SEEN             0x00000200
828 #define REG_UNFOLDED_MULTI_SEEN             0x00000400
829 /* spare */
830 #define REG_UNBOUNDED_QUANTIFIER_SEEN       0x00001000
831 
832 
833 START_EXTERN_C
834 
835 #ifdef PLUGGABLE_RE_EXTENSION
836 #include "re_nodes.h"
837 #else
838 #include "regnodes.h"
839 #endif
840 
841 #ifndef PLUGGABLE_RE_EXTENSION
842 #ifndef DOINIT
843 EXTCONST regexp_engine PL_core_reg_engine;
844 #else /* DOINIT */
845 EXTCONST regexp_engine PL_core_reg_engine = {
846         Perl_re_compile,
847         Perl_regexec_flags,
848         Perl_re_intuit_start,
849         Perl_re_intuit_string,
850         Perl_regfree_internal,
851         Perl_reg_numbered_buff_fetch,
852         Perl_reg_numbered_buff_store,
853         Perl_reg_numbered_buff_length,
854         Perl_reg_named_buff,
855         Perl_reg_named_buff_iter,
856         Perl_reg_qr_package,
857 #if defined(USE_ITHREADS)
858         Perl_regdupe_internal,
859 #endif
860         Perl_re_op_compile
861 };
862 #endif /* DOINIT */
863 #endif /* PLUGGABLE_RE_EXTENSION */
864 
865 
866 END_EXTERN_C
867 
868 
869 /* .what is a character array with one character for each member of .data
870  * The character describes the function of the corresponding .data item:
871  *   a - AV for paren_name_list under DEBUGGING
872  *   f - start-class data for regstclass optimization
873  *   l - start op for literal (?{EVAL}) item
874  *   L - start op for literal (?{EVAL}) item, with separate CV (qr//)
875  *   r - pointer to an embedded code-containing qr, e.g. /ab$qr/
876  *   s - inversion list for Unicode-style character class, and the
877  *       multicharacter strings resulting from casefolding the single-character
878  *       entries in the character class
879  *   t - trie struct
880  *   u - trie struct's widecharmap (a HV, so can't share, must dup)
881  *       also used for revcharmap and words under DEBUGGING
882  *   T - aho-trie struct
883  *   S - sv for named capture lookup
884  * 20010712 mjd@plover.com
885  * (Remember to update re_dup() and pregfree() if you add any items.)
886  */
887 struct reg_data {
888     U32 count;
889     U8 *what;
890     void* data[1];
891 };
892 
893 /* Code in S_to_utf8_substr() and S_to_byte_substr() in regexec.c accesses
894    anchored* and float* via array indexes 0 and 1.  */
895 #define anchored_substr substrs->data[0].substr
896 #define anchored_utf8 substrs->data[0].utf8_substr
897 #define anchored_offset substrs->data[0].min_offset
898 #define anchored_end_shift substrs->data[0].end_shift
899 
900 #define float_substr substrs->data[1].substr
901 #define float_utf8 substrs->data[1].utf8_substr
902 #define float_min_offset substrs->data[1].min_offset
903 #define float_max_offset substrs->data[1].max_offset
904 #define float_end_shift substrs->data[1].end_shift
905 
906 #define check_substr substrs->data[2].substr
907 #define check_utf8 substrs->data[2].utf8_substr
908 #define check_offset_min substrs->data[2].min_offset
909 #define check_offset_max substrs->data[2].max_offset
910 #define check_end_shift substrs->data[2].end_shift
911 
912 #define RX_ANCHORED_SUBSTR(rx)	(ReANY(rx)->anchored_substr)
913 #define RX_ANCHORED_UTF8(rx)	(ReANY(rx)->anchored_utf8)
914 #define RX_FLOAT_SUBSTR(rx)	(ReANY(rx)->float_substr)
915 #define RX_FLOAT_UTF8(rx)	(ReANY(rx)->float_utf8)
916 
917 /* trie related stuff */
918 
919 /* a transition record for the state machine. the
920    check field determines which state "owns" the
921    transition. the char the transition is for is
922    determined by offset from the owning states base
923    field.  the next field determines which state
924    is to be transitioned to if any.
925 */
926 struct _reg_trie_trans {
927   U32 next;
928   U32 check;
929 };
930 
931 /* a transition list element for the list based representation */
932 struct _reg_trie_trans_list_elem {
933     U16 forid;
934     U32 newstate;
935 };
936 typedef struct _reg_trie_trans_list_elem reg_trie_trans_le;
937 
938 /* a state for compressed nodes. base is an offset
939   into an array of reg_trie_trans array. If wordnum is
940   nonzero the state is accepting. if base is zero then
941   the state has no children (and will be accepting)
942 */
943 struct _reg_trie_state {
944   U16 wordnum;
945   union {
946     U32                base;
947     reg_trie_trans_le* list;
948   } trans;
949 };
950 
951 /* info per word; indexed by wordnum */
952 typedef struct {
953     U16  prev;	/* previous word in acceptance chain; eg in
954                  * zzz|abc|ab/ after matching the chars abc, the
955                  * accepted word is #2, and the previous accepted
956                  * word is #3 */
957     U32 len;	/* how many chars long is this word? */
958     U32 accept;	/* accept state for this word */
959 } reg_trie_wordinfo;
960 
961 
962 typedef struct _reg_trie_state    reg_trie_state;
963 typedef struct _reg_trie_trans    reg_trie_trans;
964 
965 
966 /* anything in here that needs to be freed later
967    should be dealt with in pregfree.
968    refcount is first in both this and _reg_ac_data to allow a space
969    optimisation in Perl_regdupe.  */
970 struct _reg_trie_data {
971     U32             refcount;        /* number of times this trie is referenced */
972     U32             lasttrans;       /* last valid transition element */
973     U16             *charmap;        /* byte to charid lookup array */
974     reg_trie_state  *states;         /* state data */
975     reg_trie_trans  *trans;          /* array of transition elements */
976     char            *bitmap;         /* stclass bitmap */
977     U16 	    *jump;           /* optional 1 indexed array of offsets before tail
978                                         for the node following a given word. */
979     reg_trie_wordinfo *wordinfo;     /* array of info per word */
980     U16             uniquecharcount; /* unique chars in trie (width of trans table) */
981     U32             startstate;      /* initial state - used for common prefix optimisation */
982     STRLEN          minlen;          /* minimum length of words in trie - build/opt only? */
983     STRLEN          maxlen;          /* maximum length of words in trie - build/opt only? */
984     U32             prefixlen;       /* #chars in common prefix */
985     U32             statecount;      /* Build only - number of states in the states array
986                                         (including the unused zero state) */
987     U32             wordcount;       /* Build only */
988 #ifdef DEBUGGING
989     STRLEN          charcount;       /* Build only */
990 #endif
991 };
992 /* There is one (3 under DEBUGGING) pointers that logically belong in this
993    structure, but are held outside as they need duplication on thread cloning,
994    whereas the rest of the structure can be read only:
995     HV              *widecharmap;    code points > 255 to charid
996 #ifdef DEBUGGING
997     AV              *words;          Array of words contained in trie, for dumping
998     AV              *revcharmap;     Map of each charid back to its character representation
999 #endif
1000 */
1001 
1002 #define TRIE_WORDS_OFFSET 2
1003 
1004 typedef struct _reg_trie_data reg_trie_data;
1005 
1006 /* refcount is first in both this and _reg_trie_data to allow a space
1007    optimisation in Perl_regdupe.  */
1008 struct _reg_ac_data {
1009     U32              refcount;
1010     U32              trie;
1011     U32              *fail;
1012     reg_trie_state   *states;
1013 };
1014 typedef struct _reg_ac_data reg_ac_data;
1015 
1016 /* ANY_BIT doesn't use the structure, so we can borrow it here.
1017    This is simpler than refactoring all of it as wed end up with
1018    three different sets... */
1019 
1020 #define TRIE_BITMAP(p)		(((reg_trie_data *)(p))->bitmap)
1021 #define TRIE_BITMAP_BYTE(p, c)	BITMAP_BYTE(TRIE_BITMAP(p), c)
1022 #define TRIE_BITMAP_SET(p, c)	(TRIE_BITMAP_BYTE(p, c) |=  ANYOF_BIT((U8)c))
1023 #define TRIE_BITMAP_CLEAR(p,c)	(TRIE_BITMAP_BYTE(p, c) &= ~ANYOF_BIT((U8)c))
1024 #define TRIE_BITMAP_TEST(p, c)	(TRIE_BITMAP_BYTE(p, c) &   ANYOF_BIT((U8)c))
1025 
1026 #define IS_ANYOF_TRIE(op) ((op)==TRIEC || (op)==AHOCORASICKC)
1027 #define IS_TRIE_AC(op) ((op)>=AHOCORASICK)
1028 
1029 
1030 #define BITMAP_BYTE(p, c)	(( (U8*) p) [ ( ( (UV) (c)) >> 3) ] )
1031 #define BITMAP_TEST(p, c)	(BITMAP_BYTE(p, c) &   ANYOF_BIT((U8)c))
1032 
1033 /* these defines assume uniquecharcount is the correct variable, and state may be evaluated twice */
1034 #define TRIE_NODENUM(state) (((state)-1)/(trie->uniquecharcount)+1)
1035 #define SAFE_TRIE_NODENUM(state) ((state) ? (((state)-1)/(trie->uniquecharcount)+1) : (state))
1036 #define TRIE_NODEIDX(state) ((state) ? (((state)-1)*(trie->uniquecharcount)+1) : (state))
1037 
1038 #ifdef DEBUGGING
1039 #define TRIE_CHARCOUNT(trie) ((trie)->charcount)
1040 #else
1041 #define TRIE_CHARCOUNT(trie) (trie_charcount)
1042 #endif
1043 
1044 #define RE_TRIE_MAXBUF_INIT 65536
1045 #define RE_TRIE_MAXBUF_NAME "\022E_TRIE_MAXBUF"
1046 #define RE_DEBUG_FLAGS "\022E_DEBUG_FLAGS"
1047 
1048 #define RE_COMPILE_RECURSION_INIT 1000
1049 #define RE_COMPILE_RECURSION_LIMIT "\022E_COMPILE_RECURSION_LIMIT"
1050 
1051 /*
1052 
1053 RE_DEBUG_FLAGS is used to control what debug output is emitted
1054 its divided into three groups of options, some of which interact.
1055 The three groups are: Compile, Execute, Extra. There is room for a
1056 further group, as currently only the low three bytes are used.
1057 
1058     Compile Options:
1059 
1060     PARSE
1061     PEEP
1062     TRIE
1063     PROGRAM
1064 
1065     Execute Options:
1066 
1067     INTUIT
1068     MATCH
1069     TRIE
1070 
1071     Extra Options
1072 
1073     TRIE
1074 
1075 If you modify any of these make sure you make corresponding changes to
1076 re.pm, especially to the documentation.
1077 
1078 */
1079 
1080 
1081 /* Compile */
1082 #define RE_DEBUG_COMPILE_MASK      0x0000FF
1083 #define RE_DEBUG_COMPILE_PARSE     0x000001
1084 #define RE_DEBUG_COMPILE_OPTIMISE  0x000002
1085 #define RE_DEBUG_COMPILE_TRIE      0x000004
1086 #define RE_DEBUG_COMPILE_DUMP      0x000008
1087 #define RE_DEBUG_COMPILE_FLAGS     0x000010
1088 #define RE_DEBUG_COMPILE_TEST      0x000020
1089 
1090 /* Execute */
1091 #define RE_DEBUG_EXECUTE_MASK      0x00FF00
1092 #define RE_DEBUG_EXECUTE_INTUIT    0x000100
1093 #define RE_DEBUG_EXECUTE_MATCH     0x000200
1094 #define RE_DEBUG_EXECUTE_TRIE      0x000400
1095 
1096 /* Extra */
1097 #define RE_DEBUG_EXTRA_MASK              0x3FF0000
1098 #define RE_DEBUG_EXTRA_TRIE              0x0010000
1099 #define RE_DEBUG_EXTRA_STATE             0x0080000
1100 #define RE_DEBUG_EXTRA_OPTIMISE          0x0100000
1101 #define RE_DEBUG_EXTRA_BUFFERS           0x0400000
1102 #define RE_DEBUG_EXTRA_GPOS              0x0800000
1103 #define RE_DEBUG_EXTRA_DUMP_PRE_OPTIMIZE 0x1000000
1104 #define RE_DEBUG_EXTRA_WILDCARD          0x2000000
1105 /* combined */
1106 #define RE_DEBUG_EXTRA_STACK             0x0280000
1107 
1108 #define RE_DEBUG_FLAG(x) (re_debug_flags & (x))
1109 /* Compile */
1110 #define DEBUG_COMPILE_r(x) DEBUG_r( \
1111     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_COMPILE_MASK)) x  )
1112 #define DEBUG_PARSE_r(x) DEBUG_r( \
1113     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_COMPILE_PARSE)) x  )
1114 #define DEBUG_OPTIMISE_r(x) DEBUG_r( \
1115     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_COMPILE_OPTIMISE)) x  )
1116 #define DEBUG_DUMP_r(x) DEBUG_r( \
1117     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_COMPILE_DUMP)) x  )
1118 #define DEBUG_TRIE_COMPILE_r(x) DEBUG_r( \
1119     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_COMPILE_TRIE)) x )
1120 #define DEBUG_FLAGS_r(x) DEBUG_r( \
1121     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_COMPILE_FLAGS)) x )
1122 #define DEBUG_TEST_r(x) DEBUG_r( \
1123     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_COMPILE_TEST)) x )
1124 /* Execute */
1125 #define DEBUG_EXECUTE_r(x) DEBUG_r( \
1126     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXECUTE_MASK)) x  )
1127 #define DEBUG_INTUIT_r(x) DEBUG_r( \
1128     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXECUTE_INTUIT)) x  )
1129 #define DEBUG_MATCH_r(x) DEBUG_r( \
1130     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXECUTE_MATCH)) x  )
1131 #define DEBUG_TRIE_EXECUTE_r(x) DEBUG_r( \
1132     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXECUTE_TRIE)) x )
1133 
1134 /* Extra */
1135 #define DEBUG_EXTRA_r(x) DEBUG_r( \
1136     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXTRA_MASK)) x  )
1137 #define DEBUG_STATE_r(x) DEBUG_r( \
1138     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXTRA_STATE)) x )
1139 #define DEBUG_STACK_r(x) DEBUG_r( \
1140     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXTRA_STACK)) x )
1141 #define DEBUG_BUFFERS_r(x) DEBUG_r( \
1142     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXTRA_BUFFERS)) x )
1143 
1144 #define DEBUG_OPTIMISE_MORE_r(x) DEBUG_r( \
1145     if (DEBUG_v_TEST || ((RE_DEBUG_EXTRA_OPTIMISE|RE_DEBUG_COMPILE_OPTIMISE) == \
1146          RE_DEBUG_FLAG(RE_DEBUG_EXTRA_OPTIMISE|RE_DEBUG_COMPILE_OPTIMISE))) x )
1147 #define DEBUG_TRIE_COMPILE_MORE_r(x) DEBUG_TRIE_COMPILE_r( \
1148     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXTRA_TRIE)) x )
1149 #define DEBUG_TRIE_EXECUTE_MORE_r(x) DEBUG_TRIE_EXECUTE_r( \
1150     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXTRA_TRIE)) x )
1151 
1152 #define DEBUG_TRIE_r(x) DEBUG_r( \
1153     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_COMPILE_TRIE \
1154         | RE_DEBUG_EXECUTE_TRIE )) x )
1155 #define DEBUG_GPOS_r(x) DEBUG_r( \
1156     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXTRA_GPOS)) x )
1157 
1158 #define DEBUG_DUMP_PRE_OPTIMIZE_r(x) DEBUG_r( \
1159     if (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXTRA_DUMP_PRE_OPTIMIZE)) x )
1160 
1161 /* initialization */
1162 /* Get the debug flags for code not in regcomp.c nor regexec.c.  This doesn't
1163  * initialize the variable if it isn't already there, instead it just assumes
1164  * the flags are 0 */
1165 #define DECLARE_AND_GET_RE_DEBUG_FLAGS_NON_REGEX                               \
1166     volatile IV re_debug_flags = 0;  PERL_UNUSED_VAR(re_debug_flags);          \
1167     STMT_START {                                                               \
1168         SV * re_debug_flags_sv = NULL;                                         \
1169                      /* get_sv() can return NULL during global destruction. */ \
1170         re_debug_flags_sv = PL_curcop ? get_sv(RE_DEBUG_FLAGS, GV_ADD) : NULL; \
1171         if (re_debug_flags_sv && SvIOK(re_debug_flags_sv))                     \
1172             re_debug_flags=SvIV(re_debug_flags_sv);                            \
1173     } STMT_END
1174 
1175 
1176 #ifdef DEBUGGING
1177 
1178 /* For use in regcomp.c and regexec.c,  Get the debug flags, and initialize to
1179  * the defaults if not done already */
1180 #define DECLARE_AND_GET_RE_DEBUG_FLAGS                                         \
1181     volatile IV re_debug_flags = 0;  PERL_UNUSED_VAR(re_debug_flags);          \
1182     DEBUG_r({                              \
1183         SV * re_debug_flags_sv = NULL;                                         \
1184                      /* get_sv() can return NULL during global destruction. */ \
1185         re_debug_flags_sv = PL_curcop ? get_sv(RE_DEBUG_FLAGS, GV_ADD) : NULL; \
1186         if (re_debug_flags_sv) {                                               \
1187             if (!SvIOK(re_debug_flags_sv)) /* If doesnt exist set to default */\
1188                 sv_setuv(re_debug_flags_sv,                                    \
1189                         /* These defaults should be kept in sync with re.pm */ \
1190                             RE_DEBUG_COMPILE_DUMP | RE_DEBUG_EXECUTE_MASK );   \
1191             re_debug_flags=SvIV(re_debug_flags_sv);                            \
1192         }                                                                      \
1193     })
1194 
1195 #define isDEBUG_WILDCARD (DEBUG_v_TEST || RE_DEBUG_FLAG(RE_DEBUG_EXTRA_WILDCARD))
1196 
1197 #define RE_PV_COLOR_DECL(rpv,rlen,isuni,dsv,pv,l,m,c1,c2)   \
1198     const char * const rpv =                                \
1199         pv_pretty((dsv), (pv), (l), (m),                    \
1200             PL_colors[(c1)],PL_colors[(c2)],                \
1201             PERL_PV_ESCAPE_RE|PERL_PV_ESCAPE_NONASCII |((isuni) ? PERL_PV_ESCAPE_UNI : 0) );         \
1202     const int rlen = SvCUR(dsv)
1203 
1204 /* This is currently unsed in the core */
1205 #define RE_SV_ESCAPE(rpv,isuni,dsv,sv,m)                            \
1206     const char * const rpv =                                        \
1207         pv_pretty((dsv), (SvPV_nolen_const(sv)), (SvCUR(sv)), (m),  \
1208             PL_colors[(c1)],PL_colors[(c2)],                        \
1209             PERL_PV_ESCAPE_RE|PERL_PV_ESCAPE_NONASCII |((isuni) ? PERL_PV_ESCAPE_UNI : 0) )
1210 
1211 #define RE_PV_QUOTED_DECL(rpv,isuni,dsv,pv,l,m)                     \
1212     const char * const rpv =                                        \
1213         pv_pretty((dsv), (pv), (l), (m),                            \
1214             PL_colors[0], PL_colors[1],                             \
1215             ( PERL_PV_PRETTY_QUOTE | PERL_PV_ESCAPE_RE | PERL_PV_ESCAPE_NONASCII | PERL_PV_PRETTY_ELLIPSES | \
1216               ((isuni) ? PERL_PV_ESCAPE_UNI : 0))                  \
1217         )
1218 
1219 #define RE_SV_DUMPLEN(ItEm) (SvCUR(ItEm) - (SvTAIL(ItEm)!=0))
1220 #define RE_SV_TAIL(ItEm) (SvTAIL(ItEm) ? "$" : "")
1221 
1222 #else /* if not DEBUGGING */
1223 
1224 #define DECLARE_AND_GET_RE_DEBUG_FLAGS  dNOOP
1225 #define RE_PV_COLOR_DECL(rpv,rlen,isuni,dsv,pv,l,m,c1,c2)  dNOOP
1226 #define RE_SV_ESCAPE(rpv,isuni,dsv,sv,m)
1227 #define RE_PV_QUOTED_DECL(rpv,isuni,dsv,pv,l,m)  dNOOP
1228 #define RE_SV_DUMPLEN(ItEm)
1229 #define RE_SV_TAIL(ItEm)
1230 #define isDEBUG_WILDCARD 0
1231 
1232 #endif /* DEBUG RELATED DEFINES */
1233 
1234 #define FIRST_NON_ASCII_DECIMAL_DIGIT 0x660  /* ARABIC_INDIC_DIGIT_ZERO */
1235 
1236 typedef enum {
1237         TRADITIONAL_BOUND = _CC_WORDCHAR,
1238         GCB_BOUND,
1239         LB_BOUND,
1240         SB_BOUND,
1241         WB_BOUND
1242 } bound_type;
1243 
1244 /* This unpacks the FLAGS field of ANYOF[HR]x nodes.  The value it contains
1245  * gives the strict lower bound for the UTF-8 start byte of any code point
1246  * matchable by the node, and a loose upper bound as well.
1247  *
1248  * The low bound is stored as 0xC0 + ((the upper 6 bits) >> 2)
1249  * The loose upper bound is determined from the lowest 2 bits and the low bound
1250  * (called x) as follows:
1251  *
1252  * 11  The upper limit of the range can be as much as (EF - x) / 8
1253  * 10  The upper limit of the range can be as much as (EF - x) / 4
1254  * 01  The upper limit of the range can be as much as (EF - x) / 2
1255  * 00  The upper limit of the range can be as much as  EF
1256  *
1257  * For motivation of this design, see commit message in
1258  * 3146c00a633e9cbed741e10146662fbcedfdb8d3 */
1259 #ifdef EBCDIC
1260 #  define MAX_ANYOF_HRx_BYTE  0xF4
1261 #else
1262 #  define MAX_ANYOF_HRx_BYTE  0xEF
1263 #endif
1264 #define LOWEST_ANYOF_HRx_BYTE(b) (((b) >> 2) + 0xC0)
1265 #define HIGHEST_ANYOF_HRx_BYTE(b)                                           \
1266                                   (LOWEST_ANYOF_HRx_BYTE(b)                 \
1267           + ((MAX_ANYOF_HRx_BYTE - LOWEST_ANYOF_HRx_BYTE(b)) >> ((b) & 3)))
1268 
1269 #endif /* PERL_REGCOMP_H_ */
1270 
1271 /*
1272  * ex: set ts=8 sts=4 sw=4 et:
1273  */
1274