Don't sink or hoist debug info instrinsics; it isn't useful. This also prevents LICM sinking from erasing debug intrinsics which don't dominate any exit block of the loop.
rdar://9143943 .
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132201 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/LICM.cpp b/lib/Transforms/Scalar/LICM.cpp
index d42d4ff..eba77d3 100644
--- a/lib/Transforms/Scalar/LICM.cpp
+++ b/lib/Transforms/Scalar/LICM.cpp
@@ -372,7 +372,11 @@
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 @@
// 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.