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-rw-r--r--lib/Transforms/Scalar/LICM.cpp9
1 files changed, 6 insertions, 3 deletions
diff --git a/lib/Transforms/Scalar/LICM.cpp b/lib/Transforms/Scalar/LICM.cpp
index d42d4ff837..eba77d3090 100644
--- a/lib/Transforms/Scalar/LICM.cpp
+++ b/lib/Transforms/Scalar/LICM.cpp
@@ -372,7 +372,11 @@ bool LICM::canSinkOrHoistInst(Instruction &I) {
return !pointerInvalidatedByLoop(LI->getOperand(0), Size,
LI->getMetadata(LLVMContext::MD_tbaa));
} else if (CallInst *CI = dyn_cast<CallInst>(&I)) {
- // Handle obvious cases efficiently.
+ // Don't sink or hoist dbg info; it's legal, but not useful.
+ if (isa<DbgInfoIntrinsic>(I))
+ return false;
+
+ // Handle simple cases by querying alias analysis.
AliasAnalysis::ModRefBehavior Behavior = AA->getModRefBehavior(CI);
if (Behavior == AliasAnalysis::DoesNotAccessMemory)
return true;
@@ -445,8 +449,7 @@ void LICM::sink(Instruction &I) {
// enough that we handle it as a special (more efficient) case. It is more
// efficient to handle because there are no PHI nodes that need to be placed.
if (ExitBlocks.size() == 1) {
- if (!isa<DbgInfoIntrinsic>(I) &&
- !DT->dominates(I.getParent(), ExitBlocks[0])) {
+ if (!DT->dominates(I.getParent(), ExitBlocks[0])) {
// Instruction is not used, just delete it.
CurAST->deleteValue(&I);
// If I has users in unreachable blocks, eliminate.