From: Yann Collet <cyan@fb.com>
Date: Mon, 5 Mar 2018 00:05:59 +0000 (-0800)
Subject: DYNAMIC_BMI2 enabled for clang
X-Git-Tag: v1.3.4~1^2~41^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d02b44cf55105c23048c5cc6290b73c79bb519a2;p=thirdparty%2Fzstd.git

DYNAMIC_BMI2 enabled for clang

clang only claims compatibility with gcc 4.2.
Consequently, recent patch which reserved DYNAMIC_BMI2 for gcc >= 4.8
also disabled it for clang.

fix : __clang__ is now enough to enable DYNAMIC_BMI2
(associated with other existing conditions : x64/x64, !bmi2)
---

diff --git a/lib/common/compiler.h b/lib/common/compiler.h
index 63d32258a..bb8730126 100644
--- a/lib/common/compiler.h
+++ b/lib/common/compiler.h
@@ -74,8 +74,11 @@
  * Enabled for clang & gcc >=4.8 on x86 when BMI2 isn't enabled by default.
  */
 #ifndef DYNAMIC_BMI2
-  #if defined(__GNUC__) && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8)) \
-      && (defined(__x86_64__) || defined(_M_X86)) && !defined(__BMI2__)
+  #if defined(__clang__)    \
+      || (defined(__GNUC__) \
+          && (__GNUC__ >= 5 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 8))) \
+      && (defined(__x86_64__) || defined(_M_X86)) \
+      && !defined(__BMI2__)
   #  define DYNAMIC_BMI2 1
   #else
   #  define DYNAMIC_BMI2 0