Module Name: src
Committed By: rillig
Date: Tue Dec 15 15:20:05 UTC 2020
Modified Files:
src/usr.bin/make: hash.c
Log Message:
make(1): clean up hash function for HashTable
Expressing a multiplication as a bit shifts and subtraction is the job
of the compiler. For humans, a multiplication is easier to read.
To generate a diff of this commit:
cvs rdiff -u -r1.58 -r1.59 src/usr.bin/make/hash.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/usr.bin/make/hash.c
diff -u src/usr.bin/make/hash.c:1.58 src/usr.bin/make/hash.c:1.59
--- src/usr.bin/make/hash.c:1.58 Mon Nov 23 17:59:21 2020
+++ src/usr.bin/make/hash.c Tue Dec 15 15:20:05 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: hash.c,v 1.58 2020/11/23 17:59:21 rillig Exp $ */
+/* $NetBSD: hash.c,v 1.59 2020/12/15 15:20:05 rillig Exp $ */
/*
* Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
@@ -74,7 +74,7 @@
#include "make.h"
/* "@(#)hash.c 8.1 (Berkeley) 6/6/93" */
-MAKE_RCSID("$NetBSD: hash.c,v 1.58 2020/11/23 17:59:21 rillig Exp $");
+MAKE_RCSID("$NetBSD: hash.c,v 1.59 2020/12/15 15:20:05 rillig Exp $");
/*
* The ratio of # entries to # buckets at which we rebuild the table to
@@ -86,10 +86,13 @@ MAKE_RCSID("$NetBSD: hash.c,v 1.58 2020/
static unsigned int
hash(const char *key, size_t *out_keylen)
{
- unsigned int h = 0;
- const char *p = key;
- while (*p != '\0')
- h = (h << 5) - h + (unsigned char)*p++;
+ unsigned int h;
+ const char *p;
+
+ h = 0;
+ for (p = key; *p != '\0'; p++)
+ h = 31 * h + (unsigned char)*p;
+
if (out_keylen != NULL)
*out_keylen = (size_t)(p - key);
return h;
