Rejig how callout blocks are allocated in pcre2_match().

This commit is contained in:
Philip.Hazel 2017-12-16 16:43:47 +00:00
parent 9e38537b87
commit 5cbab74c97
3 changed files with 40 additions and 24 deletions

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@ -82,6 +82,9 @@ subsequently picked up in the study.)
instead of "RRETURN" saves unwinding the backtracks in these cases (only one
didn't).
20. Allocate a single callout block on the stack at the start of pcre2_match()
and set its never-changing fields once only.
Version 10.30 14-August-2017
----------------------------

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@ -861,6 +861,7 @@ typedef struct match_block {
uint32_t nltype; /* Newline type */
uint32_t nllen; /* Newline string length */
PCRE2_UCHAR nl[4]; /* Newline string when fixed */
pcre2_callout_block *cb; /* Points to a callout block */
void *callout_data; /* To pass back to callouts */
int (*callout)(pcre2_callout_block *,void *); /* Callout function or NULL */
} match_block;

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@ -249,7 +249,8 @@ for (i = 0, Q = mb->match_frames;
/* This function is called for all callouts, whether "standalone" or at the
start of a conditional group. Feptr will be pointing to either OP_CALLOUT or
OP_CALLOUT_STR.
OP_CALLOUT_STR. A callout block is allocated in pcre2_match() and initialized
with fixed values.
Arguments:
F points to the current backtracking frame
@ -266,7 +267,7 @@ do_callout(heapframe *F, match_block *mb, PCRE2_SIZE *lengthptr)
int rc;
PCRE2_SIZE save0, save1;
PCRE2_SIZE *callout_ovector;
pcre2_callout_block cb;
pcre2_callout_block *cb;
*lengthptr = (*Fecode == OP_CALLOUT)?
PRIV(OP_lengths)[OP_CALLOUT] : GET(Fecode, 1 + 2*LINK_SIZE);
@ -285,38 +286,39 @@ pointer. */
callout_ovector = (PCRE2_SIZE *)(Fovector) - 2;
cb.version = 1;
cb.capture_top = (uint32_t)Foffset_top/2 + 1;
cb.capture_last = Fcapture_last;
cb.offset_vector = callout_ovector;
cb.mark = mb->nomatch_mark;
cb.subject = mb->start_subject;
cb.subject_length = (PCRE2_SIZE)(mb->end_subject - mb->start_subject);
cb.start_match = (PCRE2_SIZE)(Fstart_match - mb->start_subject);
cb.current_position = (PCRE2_SIZE)(Feptr - mb->start_subject);
cb.pattern_position = GET(Fecode, 1);
cb.next_item_length = GET(Fecode, 1 + LINK_SIZE);
/* The cb->version, cb->subject, cb->subject_length, and cb->start_match fields
are set externally. The first 3 never change; the last is updated for each
bumpalong. */
cb = mb->cb;
cb->capture_top = (uint32_t)Foffset_top/2 + 1;
cb->capture_last = Fcapture_last;
cb->offset_vector = callout_ovector;
cb->mark = mb->nomatch_mark;
cb->current_position = (PCRE2_SIZE)(Feptr - mb->start_subject);
cb->pattern_position = GET(Fecode, 1);
cb->next_item_length = GET(Fecode, 1 + LINK_SIZE);
if (*Fecode == OP_CALLOUT) /* Numerical callout */
{
cb.callout_number = Fecode[1 + 2*LINK_SIZE];
cb.callout_string_offset = 0;
cb.callout_string = NULL;
cb.callout_string_length = 0;
cb->callout_number = Fecode[1 + 2*LINK_SIZE];
cb->callout_string_offset = 0;
cb->callout_string = NULL;
cb->callout_string_length = 0;
}
else /* String callout */
{
cb.callout_number = 0;
cb.callout_string_offset = GET(Fecode, 1 + 3*LINK_SIZE);
cb.callout_string = Fecode + (1 + 4*LINK_SIZE) + 1;
cb.callout_string_length =
cb->callout_number = 0;
cb->callout_string_offset = GET(Fecode, 1 + 3*LINK_SIZE);
cb->callout_string = Fecode + (1 + 4*LINK_SIZE) + 1;
cb->callout_string_length =
*lengthptr - (1 + 4*LINK_SIZE) - 2;
}
save0 = callout_ovector[0];
save1 = callout_ovector[1];
callout_ovector[0] = callout_ovector[1] = PCRE2_UNSET;
rc = mb->callout(&cb, mb->callout_data);
rc = mb->callout(cb, mb->callout_data);
callout_ovector[0] = save0;
callout_ovector[1] = save1;
return rc;
@ -6008,6 +6010,7 @@ PCRE2_SIZE frame_size;
/* We need to have mb as a pointer to a match block, because the IS_NEWLINE
macro is used below, and it expects NLBLOCK to be defined as a pointer. */
pcre2_callout_block cb;
match_block actual_match_block;
match_block *mb = &actual_match_block;
@ -6168,6 +6171,14 @@ startline = (re->flags & PCRE2_STARTLINE) != 0;
bumpalong_limit = (mcontext->offset_limit == PCRE2_UNSET)?
end_subject : subject + mcontext->offset_limit;
/* Set up the fixed fields in the callout block, with a pointer in the
match block. */
mb->cb = &cb;
cb.version = 1;
cb.subject = subject;
cb.subject_length = (PCRE2_SIZE)(end_subject - subject);
/* Fill in the remaining fields in the match block. */
mb->callout = mcontext->callout;
@ -6632,6 +6643,7 @@ for(;;)
/* OK, we can now run the match. If "hitend" is set afterwards, remember the
first starting point for which a partial match was found. */
cb.start_match = (PCRE2_SIZE)(start_match - subject);
mb->start_used_ptr = start_match;
mb->last_used_ptr = start_match;
mb->match_call_count = 0;