[PATCH] lib: string.c: A speed optimized for strncpy

From: Rickard Strandqvist
Date: Sun Oct 05 2014 - 09:27:21 EST


This variant is in my tests about 7-10% faster, and also think
it is perhaps even clearer code than before.

Signed-off-by: Rickard Strandqvist <rickard_strandqvist@xxxxxxxxxxxxxxxxxx>
---
lib/string.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/lib/string.c b/lib/string.c
index f3c6ff5..6961229 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -123,12 +123,12 @@ char *strncpy(char *dest, const char *src, size_t count)
{
char *tmp = dest;

- while (count) {
- if ((*tmp = *src) != 0)
- src++;
- tmp++;
- count--;
- }
+ while (count && (*tmp++ = *src++))
+ --count;
+
+ while (count--)
+ *tmp++ = '\0';
+
return dest;
}
EXPORT_SYMBOL(strncpy);
--
1.7.10.4

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