micro-optimise a bit of trie code

diff --git a/regexec.c b/regexec.c
index 5cdc3cc..38c4181 100644 (file)
--- a/regexec.c
+++ b/regexec.c
@@ -1774,14 +1774,13 @@ S_find_byclass(pTHX_ regexp * prog, const regnode *c, char *s,
                             });
                             if ( base ) {
                                 U32 tmp;
+                               I32 offset;
                                 if (charid &&
-                                     (base + charid > trie->uniquecharcount )
-                                     && (base + charid - 1 - trie->uniquecharcount
-                                            < trie->lasttrans)
-                                     && trie->trans[base + charid - 1 -
-                                            trie->uniquecharcount].check == state
-                                     && (tmp=trie->trans[base + charid - 1 -
-                                        trie->uniquecharcount ].next))
+                                    ( ((offset = base + charid
+                                       - 1 - trie->uniquecharcount)) >= 0)
+                                     && ((U32)offset < trie->lasttrans)
+                                     && trie->trans[offset].check == state
+                                     && (tmp=trie->trans[offset].next))
                                 {
                                     DEBUG_TRIE_EXECUTE_r(
                                         PerlIO_printf( Perl_debug_log," - legal\n"));
@@ -3197,6 +3196,7 @@ S_regmatch(pTHX_ regmatch_info *reginfo, regnode *prog)
 
                    /* read a char and goto next state */
                    if ( base ) {
+                       I32 offset;
                        REXEC_TRIE_READ_CHAR(trie_type, trie, widecharmap, uc,
                                             uscan, len, uvc, charid, foldlen,
                                             foldbuf, uniflags);
@@ -3204,14 +3204,13 @@ S_regmatch(pTHX_ regmatch_info *reginfo, regnode *prog)
                        if (foldlen>0)
                            ST.longfold = TRUE;
                        if (charid &&
-                            (base + charid > trie->uniquecharcount )
-                            && (base + charid - 1 - trie->uniquecharcount
-                                   < trie->lasttrans)
-                            && trie->trans[base + charid - 1 -
-                                   trie->uniquecharcount].check == state)
+                            ( ((offset =
+                             base + charid - 1 - trie->uniquecharcount)) >= 0)
+
+                            && ((U32)offset < trie->lasttrans)
+                            && trie->trans[offset].check == state)
                        {
-                           state = trie->trans[base + charid - 1 -
-                               trie->uniquecharcount ].next;
+                           state = trie->trans[offset].next;
                        }
                        else {
                            state = 0;