Slightly improve av_log2 in codeclib on ARMv6.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@23866 a1c6a512-1295-4272-9138-f99709370657

1 files changed, 1 insertions, 2 deletions

diff --git a/apps/codecs/lib/codeclib.h b/apps/codecs/lib/codeclib.h
index bf7b41775a..a5ecb73027 100644
--- a/apps/codecs/lib/codeclib.h
+++ b/apps/codecs/lib/codeclib.h
@@ -79,8 +79,7 @@ unsigned udiv32_arm(unsigned a, unsigned b);
 #if (defined(CPU_ARM) && (ARM_ARCH > 4))
 static inline unsigned int av_log2(uint32_t v)
 {
-    unsigned int lz = __builtin_clz(v);
-    return 31 - lz + (lz >> 5); /* make sure av_log2(0) returns 0 */
+    return v ? 31 - __builtin_clz(v) : v;
 }
 #else
 /* From libavutil/common.h */