shithub: scc

Info  •  Files  •  Log  •  Branches

Optimize the search of keywords

It is difficult two strings with the same hash and the same initial
letter, so this test save a lot of calls to strcmp.

--- a/lex.c

+++ b/lex.c

@@ -170,12 +170,12 @@

 }

 static unsigned char

-keyword(char *s)

+keyword(register char *s)

 {

 	register struct keyword *bp;

 	for (bp = ktab[hash(s) & NR_KEYW_HASH-1]; bp; bp = bp->next) {

-		if (!strcmp(bp->str, s))

+		if (*s == *bp->str && !strcmp(bp->str, s))

 			return bp->tok;

 	}

 	return 0;