From e3ea948d4588e7efddbf0ee92147d93f827d7cea Mon Sep 17 00:00:00 2001
From: Alessandro Rubini <rubini@unipv.it>
Date: Sat, 10 Oct 2009 11:51:16 +0200
Subject: [PATCH] lib_generic memset: fill one word at a time if possible
If the destination is aligned, fill ulong values until possible.
Then fill remaining part by byte.
Signed-off-by: Alessandro Rubini <rubini@unipv.it>
Acked-by: Andrea Gallo <andrea.gallo@stericsson.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
---
lib_generic/string.c | 22 +++++++++++++++++++---
1 file changed, 19 insertions(+), 3 deletions(-)
diff --git a/lib_generic/string.c b/lib_generic/string.c
index 61a45dc94d..b375b8124a 100644
--- a/lib_generic/string.c
+++ b/lib_generic/string.c
@@ -403,10 +403,26 @@ char *strswab(const char *s)
*/
void * memset(void * s,int c,size_t count)
{
- char *xs = (char *) s;
-
+ unsigned long *sl = (unsigned long *) s;
+ unsigned long cl = 0;
+ char *s8;
+ int i;
+
+ /* do it one word at a time (32 bits or 64 bits) while possible */
+ if ( ((ulong)s & (sizeof(*sl) - 1)) == 0) {
+ for (i = 0; i < sizeof(*sl); i++) {
+ cl <<= 8;
+ cl |= c & 0xff;
+ }
+ while (count >= sizeof(*sl)) {
+ *sl++ = cl;
+ count -= sizeof(*sl);
+ }
+ }
+ /* fill 8 bits at a time */
+ s8 = (char *)sl;
while (count--)
- *xs++ = c;
+ *s8++ = c;
return s;
}
--
2.39.5