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/* regcomp.h
*/
typedef OP OP_4tree; /* Will be redefined later. */
/*
* The "internal use only" fields in regexp.h are present to pass info from
* compile to execute that permits the execute phase to run lots faster on
* simple cases. They are:
*
* regstart sv that must begin a match; Nullch if none obvious
* reganch is the match anchored (at beginning-of-line only)?
* regmust string (pointer into program) that match must include, or NULL
* [regmust changed to SV* for bminstr()--law]
* regmlen length of regmust string
* [regmlen not used currently]
*
* Regstart and reganch permit very fast decisions on suitable starting points
* for a match, cutting down the work a lot. Regmust permits fast rejection
* of lines that cannot possibly match. The regmust tests are costly enough
* that pregcomp() supplies a regmust only if the r.e. contains something
* potentially expensive (at present, the only such thing detected is * or +
* at the start of the r.e., which can involve a lot of backup). Regmlen is
* supplied because the test in pregexec() needs it and pregcomp() is computing
* it anyway.
* [regmust is now supplied always. The tests that use regmust have a
* heuristic that disables the test if it usually matches.]
*
* [In fact, we now use regmust in many cases to locate where the search
* starts in the string, so if regback is >= 0, the regmust search is never
* wasted effort. The regback variable says how many characters back from
* where regmust matched is the earliest possible start of the match.
* For instance, /[a-z].foo/ has a regmust of 'foo' and a regback of 2.]
*/
/*
* Structure for regexp "program". This is essentially a linear encoding
* of a nondeterministic finite-state machine (aka syntax charts or
* "railroad normal form" in parsing technology). Each node is an opcode
* plus a "next" pointer, possibly plus an operand. "Next" pointers of
* all nodes except BRANCH implement concatenation; a "next" pointer with
* a BRANCH on both ends of it is connecting two alternatives. (Here we
* have one of the subtle syntax dependencies: an individual BRANCH (as
* opposed to a collection of them) is never concatenated with anything
* because of operator precedence.) The operand of some types of node is
* a literal string; for others, it is a node leading into a sub-FSM. In
* particular, the operand of a BRANCH node is the first node of the branch.
* (NB this is *not* a tree structure: the tail of the branch connects
* to the thing following the set of BRANCHes.) The opcodes are:
*/
/*
* A node is one char of opcode followed by two chars of "next" pointer.
* "Next" pointers are stored as two 8-bit pieces, high order first. The
* value is a positive offset from the opcode of the node containing it.
* An operand, if any, simply follows the node. (Note that much of the
* code generation knows about this implicit relationship.)
*
* Using two bytes for the "next" pointer is vast overkill for most things,
* but allows patterns to get big without disasters.
*
* [The "next" pointer is always aligned on an even
* boundary, and reads the offset directly as a short. Also, there is no
* special test to reverse the sign of BACK pointers since the offset is
* stored negative.]
*/
struct regnode_string {
U8 flags;
U8 type;
U16 next_off;
U8 string[1];
};
struct regnode_1 {
U8 flags;
U8 type;
U16 next_off;
U32 arg1;
};
struct regnode_2 {
U8 flags;
U8 type;
U16 next_off;
U16 arg1;
U16 arg2;
};
/* XXX fix this description.
Impose a limit of REG_INFTY on various pattern matching operations
to limit stack growth and to avoid "infinite" recursions.
*/
/* The default size for REG_INFTY is I16_MAX, which is the same as
SHORT_MAX (see perl.h). Unfortunately I16 isn't necessarily 16 bits
(see handy.h). On the Cray C90, sizeof(short)==4 and hence I16_MAX is
((1<<31)-1), while on the Cray T90, sizeof(short)==8 and I16_MAX is
((1<<63)-1). To limit stack growth to reasonable sizes, supply a
smaller default.
--Andy Dougherty 11 June 1998
*/
#if SHORTSIZE > 2
# ifndef REG_INFTY
# define REG_INFTY ((1<<15)-1)
# endif
#endif
#ifndef REG_INFTY
# define REG_INFTY I16_MAX
#endif
#define ARG_VALUE(arg) (arg)
#define ARG__SET(arg,val) ((arg) = (val))
#define ARG(p) ARG_VALUE(ARG_LOC(p))
#define ARG1(p) ARG_VALUE(ARG1_LOC(p))
#define ARG2(p) ARG_VALUE(ARG2_LOC(p))
#define ARG_SET(p, val) ARG__SET(ARG_LOC(p), (val))
#define ARG1_SET(p, val) ARG__SET(ARG1_LOC(p), (val))
#define ARG2_SET(p, val) ARG__SET(ARG2_LOC(p), (val))
#ifndef lint
# define NEXT_OFF(p) ((p)->next_off)
# define NODE_ALIGN(node)
# define NODE_ALIGN_FILL(node) ((node)->flags = 0xde) /* deadbeef */
#else /* lint */
# define NEXT_OFF(p) 0
# define NODE_ALIGN(node)
# define NODE_ALIGN_FILL(node)
#endif /* lint */
#define SIZE_ALIGN NODE_ALIGN
#define OP(p) ((p)->type)
#define OPERAND(p) (((struct regnode_string *)p)->string)
#define NODE_ALIGN(node)
#define ARG_LOC(p) (((struct regnode_1 *)p)->arg1)
#define ARG1_LOC(p) (((struct regnode_2 *)p)->arg1)
#define ARG2_LOC(p) (((struct regnode_2 *)p)->arg2)
#define NODE_STEP_REGNODE 1 /* sizeof(regnode)/sizeof(regnode) */
#define EXTRA_STEP_2ARGS EXTRA_SIZE(struct regnode_2)
#define NODE_STEP_B 4
#define NEXTOPER(p) ((p) + NODE_STEP_REGNODE)
#define PREVOPER(p) ((p) - NODE_STEP_REGNODE)
#define FILL_ADVANCE_NODE(ptr, op) STMT_START { \
(ptr)->type = op; (ptr)->next_off = 0; (ptr)++; } STMT_END
#define FILL_ADVANCE_NODE_ARG(ptr, op, arg) STMT_START { \
ARG_SET(ptr, arg); FILL_ADVANCE_NODE(ptr, op); (ptr) += 1; } STMT_END
#define MAGIC 0234
#define SIZE_ONLY (PL_regcode == &PL_regdummy)
/* Flags for first parameter byte of ANYOF */
#define ANYOF_INVERT 0x40
#define ANYOF_FOLD 0x20
#define ANYOF_LOCALE 0x10
#define ANYOF_ISA 0x0F
#define ANYOF_ALNUML 0x08
#define ANYOF_NALNUML 0x04
#define ANYOF_SPACEL 0x02
#define ANYOF_NSPACEL 0x01
/* Utility macros for bitmap of ANYOF */
#define ANYOF_BYTE(p,c) (p)[1 + (((c) >> 3) & 31)]
#define ANYOF_BIT(c) (1 << ((c) & 7))
#define ANYOF_SET(p,c) (ANYOF_BYTE(p,c) |= ANYOF_BIT(c))
#define ANYOF_CLEAR(p,c) (ANYOF_BYTE(p,c) &= ~ANYOF_BIT(c))
#define ANYOF_TEST(p,c) (ANYOF_BYTE(p,c) & ANYOF_BIT(c))
#define ANY_SKIP ((33 - 1)/sizeof(regnode) + 1)
/*
* Utility definitions.
*/
#ifndef lint
#ifndef CHARMASK
#define UCHARAT(p) ((int)*(unsigned char *)(p))
#else
#define UCHARAT(p) ((int)*(p)&CHARMASK)
#endif
#else /* lint */
#define UCHARAT(p) PL_regdummy
#endif /* lint */
#define FAIL(m) croak ("/%.127s/: %s", PL_regprecomp,m)
#define FAIL2(pat,m) re_croak2("/%.127s/: ",pat,PL_regprecomp,m)
#define EXTRA_SIZE(guy) ((sizeof(guy)-1)/sizeof(struct regnode))
#define REG_SEEN_ZERO_LEN 1
#define REG_SEEN_LOOKBEHIND 2
#define REG_SEEN_GPOS 4
#define REG_SEEN_EVAL 8
#include "regnodes.h"
/* The following have no fixed length. char* since we do strchr on it. */
#ifndef DOINIT
EXTCONST char varies[];
#else
EXTCONST char varies[] = {
BRANCH, BACK, STAR, PLUS, CURLY, CURLYX, REF, REFF, REFFL,
WHILEM, CURLYM, CURLYN, BRANCHJ, IFTHEN, SUSPEND, 0
};
#endif
/* The following always have a length of 1. char* since we do strchr on it. */
#ifndef DOINIT
EXTCONST char simple[];
#else
EXTCONST char simple[] = {
ANY, SANY, ANYOF,
ALNUM, ALNUML, NALNUM, NALNUML,
SPACE, SPACEL, NSPACE, NSPACEL,
DIGIT, NDIGIT, 0
};
#endif
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