Lower MEMBARRIER on x86 and support processors without SSE2.
Fixes a pile of libgomp failures in the llvm-gcc testsuite due
to the libcall not existing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109004 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index d10f4ec..67a1540 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -343,8 +343,9 @@
if (Subtarget->hasSSE1())
setOperationAction(ISD::PREFETCH , MVT::Other, Legal);
- if (!Subtarget->hasSSE2())
- setOperationAction(ISD::MEMBARRIER , MVT::Other, Expand);
+ // We may not have a libcall for MEMBARRIER so we should lower this.
+ setOperationAction(ISD::MEMBARRIER , MVT::Other, Custom);
+
// On X86 and X86-64, atomic operations are lowered to locked instructions.
// Locked instructions, in turn, have implicit fence semantics (all memory
// operations are flushed before issuing the locked instruction, and they
@@ -7508,6 +7509,16 @@
return Sum;
}
+SDValue X86TargetLowering::LowerMEMBARRIER(SDValue Op, SelectionDAG &DAG) const{
+ DebugLoc dl = Op.getDebugLoc();
+
+ if (!Subtarget->hasSSE2())
+ return DAG.getNode(X86ISD::MEMBARRIER, dl, MVT::Other, Op.getOperand(0),
+ DAG.getConstant(0, MVT::i32));
+
+ return DAG.getNode(X86ISD::MEMBARRIER, dl, MVT::Other, Op.getOperand(0));
+}
+
SDValue X86TargetLowering::LowerCMP_SWAP(SDValue Op, SelectionDAG &DAG) const {
EVT T = Op.getValueType();
DebugLoc dl = Op.getDebugLoc();
@@ -7597,6 +7608,7 @@
SDValue X86TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
switch (Op.getOpcode()) {
default: llvm_unreachable("Should not custom lower this!");
+ case ISD::MEMBARRIER: return LowerMEMBARRIER(Op,DAG);
case ISD::ATOMIC_CMP_SWAP: return LowerCMP_SWAP(Op,DAG);
case ISD::ATOMIC_LOAD_SUB: return LowerLOAD_SUB(Op,DAG);
case ISD::BUILD_VECTOR: return LowerBUILD_VECTOR(Op, DAG);