From 804394b939614ca6ac99e31be236c019db365bb7 Mon Sep 17 00:00:00 2001
From: disservin <disservin.social@gmail.com>
Date: Sun, 16 Oct 2022 14:37:01 +0200
Subject: [PATCH] enable bit manipulation instruction set 1

bmi1 enables the use of _blsr_u64 for pop_lsb, and is availabe when avx2 is.

verified a small speedup (0.2 - 0.6%)

closes https://github.com/official-stockfish/Stockfish/pull/4202

No functional change
---
 src/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Makefile b/src/Makefile
index 1d5137d1..727466f9 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -593,7 +593,7 @@ endif
 ifeq ($(avx2),yes)
 	CXXFLAGS += -DUSE_AVX2
 	ifeq ($(comp),$(filter $(comp),gcc clang mingw))
-		CXXFLAGS += -mavx2
+		CXXFLAGS += -mavx2 -mbmi
 	endif
 endif
 
-- 
2.39.2