[Hexagon] Handle expansion of cmpxchg

llvm-svn: 273432

2 files changed, 12 insertions, 0 deletions

diff --git a/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp b/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp
index b29a43d8aae..42feffc3201 100644
--- a/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp
@@ -1715,6 +1715,9 @@ HexagonTargetLowering::HexagonTargetLowering(const TargetMachine &TM,
   setMinFunctionAlignment(2);
   setStackPointerRegisterToSaveRestore(HRI.getStackRegister());
 
+  setMaxAtomicSizeInBitsSupported(64);
+  setMinCmpXchgSizeInBits(32);
+
   if (EnableHexSDNodeSched)
     setSchedulingPreference(Sched::VLIW);
   else
@@ -3121,3 +3124,10 @@ bool HexagonTargetLowering::shouldExpandAtomicStoreInIR(StoreInst *SI) const {
   // Do not expand loads and stores that don't exceed 64 bits.
   return SI->getValueOperand()->getType()->getPrimitiveSizeInBits() > 64;
 }
+
+bool HexagonTargetLowering::shouldExpandAtomicCmpXchgInIR(
+      AtomicCmpXchgInst *AI) const {
+  const DataLayout &DL = AI->getModule()->getDataLayout();
+  unsigned Size = DL.getTypeStoreSize(AI->getCompareOperand()->getType());
+  return Size >= 4 && Size <= 8;
+}
diff --git a/llvm/lib/Target/Hexagon/HexagonISelLowering.h b/llvm/lib/Target/Hexagon/HexagonISelLowering.h
index e94c077c842..83a374ca0fb 100644
--- a/llvm/lib/Target/Hexagon/HexagonISelLowering.h
+++ b/llvm/lib/Target/Hexagon/HexagonISelLowering.h
@@ -256,6 +256,8 @@ bool isPositiveHalfWord(SDNode *N);
         Value *Addr, AtomicOrdering Ord) const override;
     AtomicExpansionKind shouldExpandAtomicLoadInIR(LoadInst *LI) const override;
     bool shouldExpandAtomicStoreInIR(StoreInst *SI) const override;
+    bool shouldExpandAtomicCmpXchgInIR(AtomicCmpXchgInst *AI) const override;
+
     AtomicExpansionKind
     shouldExpandAtomicRMWInIR(AtomicRMWInst *AI) const override {
       return AtomicExpansionKind::LLSC;