InstCombine: Don't combine loads/stores from swifterror to a new type

This generates invalid IR: the only users of swifterror can be call
arguments, loads, and stores.

rdar://28242257

llvm-svn: 281144

1 files changed, 8 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
index 16032780142..8295899251a 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineLoadStoreAlloca.cpp
@@ -465,6 +465,10 @@ static Instruction *combineLoadToOperationType(InstCombiner &IC, LoadInst &LI) {
   if (LI.use_empty())
     return nullptr;
 
+  // swifterror values can't be bitcasted.
+  if (LI.getPointerOperand()->isSwiftError())
+    return nullptr;
+
   Type *Ty = LI.getType();
   const DataLayout &DL = IC.getDataLayout();
 
@@ -997,6 +1001,10 @@ static bool combineStoreToValueType(InstCombiner &IC, StoreInst &SI) {
   if (!SI.isUnordered())
     return false;
 
+  // swifterror values can't be bitcasted.
+  if (SI.getPointerOperand()->isSwiftError())
+    return false;
+
   Value *V = SI.getValueOperand();
 
   // Fold away bit casts of the stored value by storing the original type.