Duncan deftly points out that readnone functions aren't
invalidated by stores, so they can be handled as 'simple'
operations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122785 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/EarlyCSE.cpp b/lib/Transforms/Scalar/EarlyCSE.cpp
index 6c2ea39..3d3f17b 100644
--- a/lib/Transforms/Scalar/EarlyCSE.cpp
+++ b/lib/Transforms/Scalar/EarlyCSE.cpp
@@ -56,6 +56,9 @@
}
static bool canHandle(Instruction *Inst) {
+ // This can only handle non-void readnone functions.
+ if (CallInst *CI = dyn_cast<CallInst>(Inst))
+ return CI->doesNotAccessMemory() && !CI->getType()->isVoidTy();
return isa<CastInst>(Inst) || isa<BinaryOperator>(Inst) ||
isa<GetElementPtrInst>(Inst) || isa<CmpInst>(Inst) ||
isa<SelectInst>(Inst) || isa<ExtractElementInst>(Inst) ||
@@ -105,7 +108,8 @@
Res ^= *I;
} else {
// nothing extra to hash in.
- assert((isa<BinaryOperator>(Inst) || isa<GetElementPtrInst>(Inst) ||
+ assert((isa<CallInst>(Inst) ||
+ isa<BinaryOperator>(Inst) || isa<GetElementPtrInst>(Inst) ||
isa<SelectInst>(Inst) || isa<ExtractElementInst>(Inst) ||
isa<InsertElementInst>(Inst) || isa<ShuffleVectorInst>(Inst)) &&
"Invalid/unknown instruction");