From e62f89f35b14d3d811c3776c1ea3ea5e7b9f58c3 Mon Sep 17 00:00:00 2001
From: Timo Kreuzer <timo.kreuzer@reactos.org>
Date: Fri, 21 Jan 2011 20:56:36 +0000
Subject: [PATCH] [INTRIN] - Implement _mm_sfence, _mm_lfence, __faststorefence
 (for amd64) - Don't use __sync_synchronize() for _ReadWriteBarrier, as it
 issues an mfence instruction and this is not what we want - Remove "BUGBUG"
 comment, because the fact that _ReadBarrier and _WriteBarrier are full
 (compiler) barriers isn't critical.

svn path=/trunk/; revision=50456
---
 reactos/include/crt/mingw32/intrin_x86.h | 31 ++++++++++++++++++------
 1 file changed, 23 insertions(+), 8 deletions(-)

diff --git a/reactos/include/crt/mingw32/intrin_x86.h b/reactos/include/crt/mingw32/intrin_x86.h
index 5b6f32d18a3..1be110c4473 100644
--- a/reactos/include/crt/mingw32/intrin_x86.h
+++ b/reactos/include/crt/mingw32/intrin_x86.h
@@ -79,22 +79,37 @@ extern "C" {
 #define _alloca(s) __builtin_alloca(s)
 #endif
 
-/*** Atomic operations ***/
+/*** Memory barriers ***/
 
-#if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) > 40100
-#define _ReadWriteBarrier() __sync_synchronize()
-#else
-__INTRIN_INLINE void _MemoryBarrier(void)
+#ifdef _x86_64
+__INTRIN_INLINE void __faststorefence(void)
 {
-	__asm__ __volatile__("" : : : "memory");
+    long local;
+	__asm__ __volatile__("lock; orl $0, %0;" : : "m"(local));
 }
-#define _ReadWriteBarrier() _MemoryBarrier()
 #endif
 
-/* BUGBUG: GCC only supports full barriers */
+__INTRIN_INLINE void _mm_lfence(void)
+{
+	__asm__ __volatile__("lfence");
+}
+
+__INTRIN_INLINE void _mm_sfence(void)
+{
+	__asm__ __volatile__("sfence");
+}
+
+__INTRIN_INLINE void _ReadWriteBarrier(void)
+{
+	__asm__ __volatile__("" : : : "memory");
+}
+
+/* GCC only supports full barriers */
 #define _ReadBarrier _ReadWriteBarrier
 #define _WriteBarrier _ReadWriteBarrier
 
+/*** Atomic operations ***/
+
 #if (__GNUC__ * 10000 + __GNUC_MINOR__ * 100 + __GNUC_PATCHLEVEL__) > 40100
 
 __INTRIN_INLINE char _InterlockedCompareExchange8(volatile char * const Destination, const char Exchange, const char Comperand)
-- 
2.17.1