[PATCH] lib/string.c: Improve strrchr

From: Rasmus Villemoes
Date: Wed Jan 14 2015 - 16:02:16 EST


Instead of potentially passing over the string twice in case c is not
found, just keep track of the last occurrence. According to
bloat-o-meter, this also cuts the generated code by a third (54 vs 36
bytes). Oh, and we get rid of those 7-space indented lines.

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

diff --git a/lib/string.c b/lib/string.c
index 10063300b830..f112a7fd1893 100644
--- a/lib/string.c
+++ b/lib/string.c
@@ -321,12 +321,12 @@ EXPORT_SYMBOL(strchrnul);
*/
char *strrchr(const char *s, int c)
{
- const char *p = s + strlen(s);
- do {
- if (*p == (char)c)
- return (char *)p;
- } while (--p >= s);
- return NULL;
+ const char *last = NULL;
+ do {
+ if (*s == (char)c)
+ last = s;
+ } while (*s++);
+ return (char *)last;
}
EXPORT_SYMBOL(strrchr);
#endif
--
2.1.3

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