diff options
Diffstat (limited to 'src/nvim/regexp.c')
| -rw-r--r-- | src/nvim/regexp.c | 149 |
1 files changed, 101 insertions, 48 deletions
diff --git a/src/nvim/regexp.c b/src/nvim/regexp.c index 8b7033b64b..d5e963c2f8 100644 --- a/src/nvim/regexp.c +++ b/src/nvim/regexp.c @@ -6914,13 +6914,8 @@ static regengine_T bt_regengine = bt_regcomp, bt_regfree, bt_regexec_nl, - bt_regexec_multi -#ifdef REGEXP_DEBUG - ,(char_u *)"" -#endif -#ifdef DEBUG - ,NULL -#endif + bt_regexec_multi, + (char_u *)"" }; @@ -6934,21 +6929,14 @@ static regengine_T nfa_regengine = nfa_regcomp, nfa_regfree, nfa_regexec_nl, - nfa_regexec_multi -#ifdef REGEXP_DEBUG - ,(char_u *)"" -#endif -#ifdef DEBUG - , NULL -#endif + nfa_regexec_multi, + (char_u *)"" }; /* Which regexp engine to use? Needed for vim_regcomp(). * Must match with 'regexpengine'. */ static int regexp_engine = 0; -#define AUTOMATIC_ENGINE 0 -#define BACKTRACKING_ENGINE 1 -#define NFA_ENGINE 2 + #ifdef REGEXP_DEBUG static char_u regname[][30] = { "AUTOMATIC Regexp Engine", @@ -6990,10 +6978,8 @@ regprog_T *vim_regcomp(char_u *expr_arg, int re_flags) regexp_engine = AUTOMATIC_ENGINE; } } -#ifdef REGEXP_DEBUG bt_regengine.expr = expr; nfa_regengine.expr = expr; -#endif /* * First try the NFA engine, unless backtracking was requested. @@ -7003,11 +6989,12 @@ regprog_T *vim_regcomp(char_u *expr_arg, int re_flags) else prog = bt_regengine.regcomp(expr, re_flags); - if (prog == NULL) { /* error compiling regexp with initial engine */ + // Check for error compiling regexp with initial engine. + if (prog == NULL) { #ifdef BT_REGEXP_DEBUG_LOG - if (regexp_engine != BACKTRACKING_ENGINE) { /* debugging log for NFA */ - FILE *f; - f = fopen(BT_REGEXP_DEBUG_LOG_NAME, "a"); + // Debugging log for NFA. + if (regexp_engine != BACKTRACKING_ENGINE) { + FILE *f = fopen(BT_REGEXP_DEBUG_LOG_NAME, "a"); if (f) { fprintf(f, "Syntax error in \"%s\"\n", expr); fclose(f); @@ -7016,12 +7003,22 @@ regprog_T *vim_regcomp(char_u *expr_arg, int re_flags) BT_REGEXP_DEBUG_LOG_NAME); } #endif - /* - * If the NFA engine failed, the backtracking engine won't work either. - * - if (regexp_engine == AUTOMATIC_ENGINE) - prog = bt_regengine.regcomp(expr, re_flags); - */ + // If the NFA engine failed, try the backtracking engine. + // Disabled for now, both engines fail on the same patterns. + // Re-enable when regcomp() fails when the pattern would work better + // with the other engine. + // + // if (regexp_engine == AUTOMATIC_ENGINE) { + // prog = bt_regengine.regcomp(expr, re_flags); + // regexp_engine = BACKTRACKING_ENGINE; + // } + } + + if (prog != NULL) { + // Store the info needed to call regcomp() again when the engine turns out + // to be very slow when executing it. + prog->re_engine = regexp_engine; + prog->re_flags = re_flags; } return prog; @@ -7036,29 +7033,62 @@ void vim_regfree(regprog_T *prog) prog->engine->regfree(prog); } -/* - * Match a regexp against a string. - * "rmp->regprog" is a compiled regexp as returned by vim_regcomp(). - * Uses curbuf for line count and 'iskeyword'. - * - * Return TRUE if there is a match, FALSE if not. - */ -int -vim_regexec ( - regmatch_T *rmp, - char_u *line, /* string to match against */ - colnr_T col /* column to start looking for match */ -) +static void report_re_switch(char_u *pat) { - return rmp->regprog->engine->regexec_nl(rmp, line, col, false); + if (p_verbose > 0) { + verbose_enter(); + MSG_PUTS(_("Switching to backtracking RE engine for pattern: ")); + MSG_PUTS(pat); + verbose_leave(); + } } -/* - * Like vim_regexec(), but consider a "\n" in "line" to be a line break. - */ +/// Matches a regexp against a string. +/// "rmp->regprog" is a compiled regexp as returned by vim_regcomp(). +/// Uses curbuf for line count and 'iskeyword'. +/// When "nl" is true consider a "\n" in "line" to be a line break. +/// +/// @param rmp +/// @param line the string to match against +/// @param col the column to start looking for match +/// @param nl +/// +/// @return TRUE if there is a match, FALSE if not. +static int vim_regexec_both(regmatch_T *rmp, char_u *line, colnr_T col, bool nl) +{ + int result = rmp->regprog->engine->regexec_nl(rmp, line, col, nl); + + // NFA engine aborted because it's very slow, use backtracking engine instead. + if (rmp->regprog->re_engine == AUTOMATIC_ENGINE + && result == NFA_TOO_EXPENSIVE) { + int save_p_re = p_re; + int re_flags = rmp->regprog->re_flags; + char_u *pat = vim_strsave(((nfa_regprog_T *)rmp->regprog)->pattern); + + p_re = BACKTRACKING_ENGINE; + vim_regfree(rmp->regprog); + report_re_switch(pat); + rmp->regprog = vim_regcomp(pat, re_flags); + if (rmp->regprog != NULL) { + result = rmp->regprog->engine->regexec_nl(rmp, line, col, nl); + } + + free(pat); + p_re = save_p_re; + } + + return result; +} + +int vim_regexec(regmatch_T *rmp, char_u *line, colnr_T col) +{ + return vim_regexec_both(rmp, line, col, false); +} + +// Like vim_regexec(), but consider a "\n" in "line" to be a line break. int vim_regexec_nl(regmatch_T *rmp, char_u *line, colnr_T col) { - return rmp->regprog->engine->regexec_nl(rmp, line, col, true); + return vim_regexec_both(rmp, line, col, true); } /* @@ -7078,5 +7108,28 @@ long vim_regexec_multi( proftime_T *tm /* timeout limit or NULL */ ) { - return rmp->regprog->engine->regexec_multi(rmp, win, buf, lnum, col, tm); + int result = rmp->regprog->engine->regexec_multi(rmp, win, buf, lnum, col, + tm); + + // NFA engine aborted because it's very slow, use backtracking engine instead. + if (rmp->regprog->re_engine == AUTOMATIC_ENGINE + && result == NFA_TOO_EXPENSIVE) { + int save_p_re = p_re; + int re_flags = rmp->regprog->re_flags; + char_u *pat = vim_strsave(((nfa_regprog_T *)rmp->regprog)->pattern); + + p_re = BACKTRACKING_ENGINE; + vim_regfree(rmp->regprog); + report_re_switch(pat); + rmp->regprog = vim_regcomp(pat, re_flags); + if (rmp->regprog != NULL) { + result = rmp->regprog->engine->regexec_multi(rmp, win, buf, lnum, col, + tm); + } + + free(pat); + p_re = save_p_re; + } + + return result; } |