2 files changed, 20 insertions, 30 deletions

diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
index 5cbb6a2338f..f9b38fa5859 100644
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -7612,6 +7612,17 @@ Value *CodeGenFunction::EmitX86BuiltinExpr(unsigned BuiltinID,
     Builder.CreateStore(HigherBits, HighBitsAddress);
     return Builder.CreateIntCast(MulResult, ResType, IsSigned);
   }
+
+  case X86::BI__faststorefence: {
+    return Builder.CreateFence(llvm::AtomicOrdering::SequentiallyConsistent,
+                               llvm::CrossThread);
+  }
+  case X86::BI_ReadWriteBarrier:
+  case X86::BI_ReadBarrier:
+  case X86::BI_WriteBarrier: {
+    return Builder.CreateFence(llvm::AtomicOrdering::SequentiallyConsistent,
+                               llvm::SingleThread);
+  }
   }
 }
 
diff --git a/clang/lib/Headers/intrin.h b/clang/lib/Headers/intrin.h
index 100da0b0d70..5a73ecec1ca 100644
--- a/clang/lib/Headers/intrin.h
+++ b/clang/lib/Headers/intrin.h
@@ -256,10 +256,12 @@ static __inline__
 unsigned long __cdecl _lrotl(unsigned long, int);
 static __inline__
 unsigned long __cdecl _lrotr(unsigned long, int);
-static __inline__
-void _ReadBarrier(void);
-static __inline__
-void _ReadWriteBarrier(void);
+static __inline__ void
+__attribute__((__deprecated__("use other intrinsics or C++11 atomics instead")))
+_ReadBarrier(void);
+static __inline__ void
+__attribute__((__deprecated__("use other intrinsics or C++11 atomics instead")))
+_ReadWriteBarrier(void);
 static __inline__
 void *_ReturnAddress(void);
 unsigned int _rorx_u32(unsigned int, const unsigned int);
@@ -288,8 +290,9 @@ unsigned int _shrx_u32(unsigned int, unsigned int);
 void _Store_HLERelease(long volatile *, long);
 void _Store64_HLERelease(__int64 volatile *, __int64);
 void _StorePointer_HLERelease(void *volatile *, void *);
-static __inline__
-void _WriteBarrier(void);
+static __inline__ void
+__attribute__((__deprecated__("use other intrinsics or C++11 atomics instead")))
+_WriteBarrier(void);
 unsigned __int32 xbegin(void);
 void _xend(void);
 static __inline__
@@ -1045,30 +1048,6 @@ _InterlockedCompareExchange64_rel(__int64 volatile *_Destination,
 }
 #endif
 /*----------------------------------------------------------------------------*\
-|* Barriers
-\*----------------------------------------------------------------------------*/
-static __inline__ void __DEFAULT_FN_ATTRS
-__attribute__((__deprecated__("use other intrinsics or C++11 atomics instead")))
-_ReadWriteBarrier(void) {
-  __atomic_signal_fence(__ATOMIC_SEQ_CST);
-}
-static __inline__ void __DEFAULT_FN_ATTRS
-__attribute__((__deprecated__("use other intrinsics or C++11 atomics instead")))
-_ReadBarrier(void) {
-  __atomic_signal_fence(__ATOMIC_SEQ_CST);
-}
-static __inline__ void __DEFAULT_FN_ATTRS
-__attribute__((__deprecated__("use other intrinsics or C++11 atomics instead")))
-_WriteBarrier(void) {
-  __atomic_signal_fence(__ATOMIC_SEQ_CST);
-}
-#ifdef __x86_64__
-static __inline__ void __DEFAULT_FN_ATTRS
-__faststorefence(void) {
-  __atomic_thread_fence(__ATOMIC_SEQ_CST);
-}
-#endif
-/*----------------------------------------------------------------------------*\
 |* readfs, readgs
 |* (Pointers in address space #256 and #257 are relative to the GS and FS
 |* segment registers, respectively.)