When using libcall expansions for the atomic intrinsics, the explicit
MEMBARRIER fences aren't necessary for ARM. Tell the combiner to fold them
away.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106631 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/ARM/ARMISelLowering.cpp b/lib/Target/ARM/ARMISelLowering.cpp
index 7f89b2d..97a5f9d 100644
--- a/lib/Target/ARM/ARMISelLowering.cpp
+++ b/lib/Target/ARM/ARMISelLowering.cpp
@@ -441,6 +441,8 @@
setOperationAction(ISD::ATOMIC_LOAD_NAND, MVT::i8, Expand);
setOperationAction(ISD::ATOMIC_LOAD_NAND, MVT::i16, Expand);
setOperationAction(ISD::ATOMIC_LOAD_NAND, MVT::i32, Expand);
+ // Since the libcalls include locking, fold in the fences
+ setShouldFoldAtomicFences(true);
}
// 64-bit versions are always libcalls (for now)
setOperationAction(ISD::ATOMIC_CMP_SWAP, MVT::i64, Expand);