use a compiler builtin (which uses processor instructions) for this operation

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@33933 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 6 insertions, 5 deletions

diff --git a/channels/chan_agent.c b/channels/chan_agent.c
index 6bbc89cb3..fb77a9456 100644
--- a/channels/chan_agent.c
+++ b/channels/chan_agent.c
@@ -1334,12 +1334,13 @@ static struct ast_channel *agent_request(const char *type, int format, void *dat
 	return chan;
 }
 
-static int powerof(unsigned int v)
+static force_inline int powerof(unsigned int d)
 {
-	int x;
-	for (x=0;x<32;x++) {
-		if (v & (1 << x)) return x;
-	}
+	int x = ffs(d);
+
+	if (x)
+		return x - 1;
+
 	return 0;
 }