1 files changed, 14 insertions, 3 deletions
diff --git a/llvm/lib/CodeGen/AtomicExpandPass.cpp b/llvm/lib/CodeGen/AtomicExpandPass.cpp
index 044f073..3f3d5dc9 100644
--- a/llvm/lib/CodeGen/AtomicExpandPass.cpp
+++ b/llvm/lib/CodeGen/AtomicExpandPass.cpp
@@ -65,6 +65,17 @@ class AtomicExpandImpl {
   const DataLayout *DL = nullptr;
 
 private:
+  void handleFailure(Instruction &FailedInst, const Twine &Msg) const {
+    LLVMContext &Ctx = FailedInst.getContext();
+
+    // TODO: Do not use generic error type.
+    Ctx.emitError(&FailedInst, Msg);
+
+    if (!FailedInst.getType()->isVoidTy())
+      FailedInst.replaceAllUsesWith(PoisonValue::get(FailedInst.getType()));
+    FailedInst.eraseFromParent();
+  }
+
   bool bracketInstWithFences(Instruction *I, AtomicOrdering Order);
   IntegerType *getCorrespondingIntegerType(Type *T, const DataLayout &DL);
   LoadInst *convertAtomicLoadToIntegerType(LoadInst *LI);
@@ -1744,7 +1755,7 @@ void AtomicExpandImpl::expandAtomicLoadToLibcall(LoadInst *I) {
       I, Size, I->getAlign(), I->getPointerOperand(), nullptr, nullptr,
       I->getOrdering(), AtomicOrdering::NotAtomic, Libcalls);
   if (!expanded)
-    report_fatal_error("expandAtomicOpToLibcall shouldn't fail for Load");
+    handleFailure(*I, "unsupported atomic load");
 }
 
 void AtomicExpandImpl::expandAtomicStoreToLibcall(StoreInst *I) {
@@ -1757,7 +1768,7 @@ void AtomicExpandImpl::expandAtomicStoreToLibcall(StoreInst *I) {
       I, Size, I->getAlign(), I->getPointerOperand(), I->getValueOperand(),
       nullptr, I->getOrdering(), AtomicOrdering::NotAtomic, Libcalls);
   if (!expanded)
-    report_fatal_error("expandAtomicOpToLibcall shouldn't fail for Store");
+    handleFailure(*I, "unsupported atomic store");
 }
 
 void AtomicExpandImpl::expandAtomicCASToLibcall(AtomicCmpXchgInst *I) {
@@ -1772,7 +1783,7 @@ void AtomicExpandImpl::expandAtomicCASToLibcall(AtomicCmpXchgInst *I) {
       I->getCompareOperand(), I->getSuccessOrdering(), I->getFailureOrdering(),
       Libcalls);
   if (!expanded)
-    report_fatal_error("expandAtomicOpToLibcall shouldn't fail for CAS");
+    handleFailure(*I, "unsupported cmpxchg");
 }
 
 static ArrayRef<RTLIB::Libcall> GetRMWLibcall(AtomicRMWInst::BinOp Op) {