From 24a19b7a189d9438ad75a651233bd213595d8903 Mon Sep 17 00:00:00 2001
From: Jeffrey Walton <noloader@gmail.com>
Date: Mon, 9 Oct 2017 21:14:21 -0400
Subject: [PATCH] Cleanup use of BMI intrinsics under GCC and compatibles

---
 misc.h | 35 +++++++++--------------------------
 1 file changed, 9 insertions(+), 26 deletions(-)

diff --git a/misc.h b/misc.h
index 36bae7cf..8c421c23 100644
--- a/misc.h
+++ b/misc.h
@@ -1,4 +1,3 @@
-
 // misc.h - originally written and placed in the public domain by Wei Dai
 
 //! \file misc.h
@@ -67,27 +66,11 @@
 #include <byteswap.h>
 #endif
 
-#if defined(__GNUC__) && defined(__BMI__)
-# include <immintrin.h>
-# if defined(__clang__)
-#  ifndef _tzcnt_u32
-#   define _tzcnt_u32(x) __tzcnt_u32(x)
-#  endif
-#  ifndef _blsr_u32
-#    define  _blsr_u32(x)  __blsr_u32(x)
-#  endif
-#  ifdef __x86_64__
-#   ifndef _tzcnt_u64
-#    define _tzcnt_u64(x) __tzcnt_u64(x)
-#   endif
-#   ifndef _blsr_u64
-#     define  _blsr_u64(x)  __blsr_u64(x)
-#   endif
-#  endif  // x86_64
-# endif  // Clang
-#endif  // GNUC and BMI
+#if defined(__BMI__)
+# include <x86intrin.h>
+#endif  // GCC and BMI
 
-#endif // CRYPTOPP_DOXYGEN_PROCESSING
+#endif  // CRYPTOPP_DOXYGEN_PROCESSING
 
 #if CRYPTOPP_DOXYGEN_PROCESSING
 //! \brief The maximum value of a machine word
@@ -730,7 +713,7 @@ inline unsigned int TrailingZeros(word32 v)
 	// We don't enable for Microsoft because it requires a runtime check.
 	// http://msdn.microsoft.com/en-us/library/hh977023%28v=vs.110%29.aspx
 	CRYPTOPP_ASSERT(v != 0);
-#if defined(__GNUC__) && defined(__BMI__)
+#if defined(__BMI__)
 	return (unsigned int)_tzcnt_u32(v);
 #elif defined(__GNUC__) && (CRYPTOPP_GCC_VERSION >= 30400)
 	return (unsigned int)__builtin_ctz(v);
@@ -761,7 +744,7 @@ inline unsigned int TrailingZeros(word64 v)
 	// We don't enable for Microsoft because it requires a runtime check.
 	// http://msdn.microsoft.com/en-us/library/hh977023%28v=vs.110%29.aspx
 	CRYPTOPP_ASSERT(v != 0);
-#if defined(__GNUC__) && defined(__BMI__) && defined(__x86_64__)
+#if defined(__BMI__) && defined(__x86_64__)
 	return (unsigned int)_tzcnt_u64(v);
 #elif defined(__GNUC__) && (CRYPTOPP_GCC_VERSION >= 30400)
 	return (unsigned int)__builtin_ctzll(v);
@@ -869,7 +852,7 @@ inline bool IsPowerOf2(const T &value)
 	return value > 0 && (value & (value-1)) == 0;
 }
 
-#if defined(__GNUC__) && defined(__BMI__)
+#if defined(__BMI__)
 template <>
 inline bool IsPowerOf2<word32>(const word32 &value)
 {
@@ -882,8 +865,8 @@ inline bool IsPowerOf2<word64>(const word64 &value)
 {
 	return value > 0 && _blsr_u64(value) == 0;
 }
-# endif
-#endif
+# endif  // __x86_64__
+#endif   // __BMI__
 
 //! \brief Performs a saturating subtract clamped at 0
 //! \tparam T1 class or type