Fix regexp slowness reported by Wade Klaver.

diff --git a/src/backend/regex/regcomp.c b/src/backend/regex/regcomp.c
index 71e69dea618177e3a152e3e9a2386151b26ff97e..06c99139770cc5829068ab872320cbde18443ebb 100644 (file)
--- a/src/backend/regex/regcomp.c
+++ b/src/backend/regex/regcomp.c
@@ -178,6 +178,9 @@ pg_regcomp(regex_t *preg, const char *pattern, int cflags)
        int                     i;
        size_t          len;
        pg_wchar   *wcp;
+       size_t  csetsize;
+
+       csetsize = (pg_database_encoding_max_length() == 1)?(SCHAR_MAX - SCHAR_MIN + 1):NC;
 
        if (cclasses == NULL)
                cclasses = cclass_init();
@@ -211,7 +214,7 @@ pg_regcomp(regex_t *preg, const char *pattern, int cflags)
 
        /* do the mallocs early so failure handling is easy */
        g = (struct re_guts *) malloc(sizeof(struct re_guts) +
-                                                                 (NC - 1) * sizeof(cat_t));
+                                                                 (csetsize - 1) * sizeof(cat_t));
        if (g == NULL)
                return REG_ESPACE;
        p->ssize = len / (size_t) 2 *(size_t) 3 + (size_t) 1;           /* ugh */
@@ -235,7 +238,7 @@ pg_regcomp(regex_t *preg, const char *pattern, int cflags)
                p->pbegin[i] = 0;
                p->pend[i] = 0;
        }
-       g->csetsize = NC;
+       g->csetsize = csetsize;
        g->sets = NULL;
        g->setbits = NULL;
        g->ncsets = 0;
@@ -248,7 +251,7 @@ pg_regcomp(regex_t *preg, const char *pattern, int cflags)
        g->nsub = 0;
        g->ncategories = 1;                     /* category 0 is "everything else" */
        g->categories = &g->catspace[-(CHAR_MIN)];
-       memset((char *) g->catspace, 0, NC * sizeof(cat_t));
+       memset((char *) g->catspace, 0, csetsize * sizeof(cat_t));
        g->backrefs = 0;
 
        /* do it */