Basic blocks typically have few predecessors. Use a SmallDenseMap to
avoid a heap allocation when this is the case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192602 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/SSAUpdater.cpp b/lib/Transforms/Utils/SSAUpdater.cpp
index fc85ef3..30adbfa 100644
--- a/lib/Transforms/Utils/SSAUpdater.cpp
+++ b/lib/Transforms/Utils/SSAUpdater.cpp
@@ -63,7 +63,7 @@
}
static bool IsEquivalentPHI(PHINode *PHI,
- DenseMap<BasicBlock*, Value*> &ValueMapping) {
+ SmallDenseMap<BasicBlock*, Value*, 8> &ValueMapping) {
unsigned PHINumValues = PHI->getNumIncomingValues();
if (PHINumValues != ValueMapping.size())
return false;
@@ -136,8 +136,8 @@
// Otherwise, we do need a PHI: check to see if we already have one available
// in this block that produces the right value.
if (isa<PHINode>(BB->begin())) {
- DenseMap<BasicBlock*, Value*> ValueMapping(PredValues.begin(),
- PredValues.end());
+ SmallDenseMap<BasicBlock*, Value*, 8> ValueMapping(PredValues.begin(),
+ PredValues.end());
PHINode *SomePHI;
for (BasicBlock::iterator It = BB->begin();
(SomePHI = dyn_cast<PHINode>(It)); ++It) {