Module Name: src
Committed By: rmind
Date: Sat Oct 26 21:06:38 UTC 2013
Modified Files:
src/common/lib/libc/hash/murmurhash: murmurhash.c
Log Message:
murmurhash2: add an optimised path for the aligned pointer case.
To generate a diff of this commit:
cvs rdiff -u -r1.5 -r1.6 src/common/lib/libc/hash/murmurhash/murmurhash.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/common/lib/libc/hash/murmurhash/murmurhash.c
diff -u src/common/lib/libc/hash/murmurhash/murmurhash.c:1.5 src/common/lib/libc/hash/murmurhash/murmurhash.c:1.6
--- src/common/lib/libc/hash/murmurhash/murmurhash.c:1.5 Sun Jun 30 12:20:32 2013
+++ src/common/lib/libc/hash/murmurhash/murmurhash.c Sat Oct 26 21:06:38 2013
@@ -1,4 +1,4 @@
-/* $NetBSD: murmurhash.c,v 1.5 2013/06/30 12:20:32 rmind Exp $ */
+/* $NetBSD: murmurhash.c,v 1.6 2013/10/26 21:06:38 rmind Exp $ */
/*
* MurmurHash2 -- from the original code:
@@ -14,18 +14,19 @@
#include <sys/cdefs.h>
#if defined(_KERNEL) || defined(_STANDALONE)
-__KERNEL_RCSID(0, "$NetBSD: murmurhash.c,v 1.5 2013/06/30 12:20:32 rmind Exp $");
+__KERNEL_RCSID(0, "$NetBSD: murmurhash.c,v 1.6 2013/10/26 21:06:38 rmind Exp $");
#else
#if defined(LIBC_SCCS) && !defined(lint)
-__RCSID("$NetBSD: murmurhash.c,v 1.5 2013/06/30 12:20:32 rmind Exp $");
+__RCSID("$NetBSD: murmurhash.c,v 1.6 2013/10/26 21:06:38 rmind Exp $");
#endif /* LIBC_SCCS and not lint */
#include "namespace.h"
#endif
#include <sys/types.h>
+#include <sys/param.h>
#include <sys/hash.h>
#if !defined(_KERNEL) && !defined(_STANDALONE)
@@ -48,23 +49,39 @@ murmurhash2(const void *key, size_t len,
const uint8_t *data = key;
uint32_t h = seed ^ (uint32_t)len;
- while (len >= sizeof(uint32_t)) {
- uint32_t k;
-
- k = data[0];
- k |= data[1] << 8;
- k |= data[2] << 16;
- k |= data[3] << 24;
-
- k *= m;
- k ^= k >> r;
- k *= m;
-
- h *= m;
- h ^= k;
-
- data += sizeof(uint32_t);
- len -= sizeof(uint32_t);
+ if (__predict_true(ALIGNED_POINTER(key, uint32_t))) {
+ while (len >= sizeof(uint32_t)) {
+ uint32_t k = *(const uint32_t *)data;
+
+ k *= m;
+ k ^= k >> r;
+ k *= m;
+
+ h *= m;
+ h ^= k;
+
+ data += sizeof(uint32_t);
+ len -= sizeof(uint32_t);
+ }
+ } else {
+ while (len >= sizeof(uint32_t)) {
+ uint32_t k;
+
+ k = data[0];
+ k |= data[1] << 8;
+ k |= data[2] << 16;
+ k |= data[3] << 24;
+
+ k *= m;
+ k ^= k >> r;
+ k *= m;
+
+ h *= m;
+ h ^= k;
+
+ data += sizeof(uint32_t);
+ len -= sizeof(uint32_t);
+ }
}
/* Handle the last few bytes of the input array. */
