From: lucasart <lucas.braesch@gmail.com>
Date: Tue, 1 Jul 2014 12:46:16 +0000 (+0800)
Subject: Use compiler intrinsic instead of assembly for popcnt
X-Git-Url: https://git.sesse.net/?p=stockfish;a=commitdiff_plain;h=a69f1d7c2060dc7b320a7b4801105df00b22a96a;ds=inline

Use compiler intrinsic instead of assembly for popcnt
No functional change.
---

diff --git a/src/Makefile b/src/Makefile
index 187e7b31..562192ca 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -285,7 +285,7 @@ endif
 
 ### 3.9 popcnt
 ifeq ($(popcnt),yes)
-	CXXFLAGS += -msse3 -DUSE_POPCNT
+	CXXFLAGS += -msse4.2 -DUSE_POPCNT
 endif
 
 ### 3.10 pext
diff --git a/src/bitcount.h b/src/bitcount.h
index f84c51cb..9feed19f 100644
--- a/src/bitcount.h
+++ b/src/bitcount.h
@@ -96,8 +96,7 @@ inline int popcount<CNT_HW_POPCNT>(Bitboard b) {
 
 #else
 
-  __asm__("popcnt %1, %0" : "=r" (b) : "r" (b));
-  return b;
+  return __builtin_popcountll(b);
 
 #endif
 }