From 9109f14ea10d6cd0dd0605a2e2b9ad8398cbf392 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Piotr=20Da=C5=82ek?= <piotr.dalek@ts.fujitsu.com>
Date: Thu, 19 Nov 2015 10:57:46 +0100
Subject: [PATCH] common/hobject.h: don't reverse bits in zero
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Zero is passed in around 30% of all calls to _reverse_bits (and most of
them during daemon startup). Optimize this by not doing anything in
that special case and returning 0.

Signed-off-by: Piotr Dałek <piotr.dalek@ts.fujitsu.com>
---
 src/common/hobject.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/common/hobject.h b/src/common/hobject.h
index 4698756515556..601af40fa43f6 100644
--- a/src/common/hobject.h
+++ b/src/common/hobject.h
@@ -176,6 +176,8 @@ public:
   }
 
   static uint32_t _reverse_bits(uint32_t v) {
+    if (v == 0)
+      return v;
     // reverse bits
     // swap odd and even bits
     v = ((v >> 1) & 0x55555555) | ((v & 0x55555555) << 1);
-- 
2.39.5