diff options
| -rw-r--r-- | match.c | 22 |
1 files changed, 17 insertions, 5 deletions
@@ -231,9 +231,10 @@ static inline pat_t *deref(match_ctx_t *ctx, pat_t *pat) // // Find and return the first and simplest pattern that will definitely have to -// match for the whole pattern to match (if any) +// match for the whole pattern to match (if any). Ideally, this would be a +// string literal that can be quickly scanned for. // -static pat_t *first_pat(match_ctx_t *ctx, pat_t *pat) +static pat_t *get_prerequisite(match_ctx_t *ctx, pat_t *pat) { for (pat_t *p = pat; p; ) { switch (p->type) { @@ -245,7 +246,13 @@ static pat_t *first_pat(match_ctx_t *ctx, pat_t *pat) p = p->args.repetitions.repeat_pat; break; case BP_CAPTURE: p = p->args.capture.capture_pat; break; - case BP_CHAIN: case BP_MATCH: case BP_NOT_MATCH: + case BP_CHAIN: { + pat_t *f = p->args.multiple.first; + // If pattern is something like (|"foo"|), then use "foo" as the first thing to scan for + p = (f->type == BP_WORD_BOUNDARY || f->type == BP_START_OF_LINE) ? p->args.multiple.second : f; + break; + } + case BP_MATCH: case BP_NOT_MATCH: p = p->args.multiple.first; break; case BP_REPLACE: p = p->args.replace.pat; break; @@ -282,11 +289,13 @@ static match_t *_next_match(match_ctx_t *ctx, const char *str, pat_t *pat, pat_t cache_destroy(ctx, NULL); pat = deref(ctx, pat); // Avoid repeated lookups - pat_t *first = first_pat(ctx, pat); + pat_t *first = get_prerequisite(ctx, pat); - // Don't bother looping if this can only match at the start: + // Don't bother looping if this can only match at the start/end: if (first->type == BP_START_OF_FILE) return match(ctx, str, pat); + else if (first->type == BP_END_OF_FILE) + return match(ctx, ctx->end, pat); // Performance optimization: if the pattern starts with a string literal, // we can just rely on the highly optimized memmem() implementation to skip @@ -294,6 +303,9 @@ static match_t *_next_match(match_ctx_t *ctx, const char *str, pat_t *pat, pat_t if (!skip && first->type == BP_STRING && first->min_matchlen > 0 && !ctx->ignorecase) { char *found = memmem(str, (size_t)(ctx->end - str), first->args.string, first->min_matchlen); str = found ? found : ctx->end; + } else if (!skip && str > ctx->start && (first->type == BP_START_OF_LINE || first->type == BP_END_OF_LINE)) { + char *found = memchr(str, '\n', (size_t)(ctx->end - str)); + str = found ? (first->type == BP_START_OF_LINE ? found+1 : found) : ctx->end; } do { |