Update profile during memory instrinsic optimization

Summary:
Ensure that the new merge BB (which contains the rest of the original BB
after the mem op being optimized) gets a profile frequency, in case
there are additional mem ops later in the BB. Otherwise they get skipped
as the merge BB looks cold.

Reviewers: davidxl, xur

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D32447

llvm-svn: 301244

1 files changed, 3 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/IndirectCallPromotion.cpp b/llvm/lib/Transforms/Instrumentation/IndirectCallPromotion.cpp
index 61d627673c9..d7eb857cff7 100644
--- a/llvm/lib/Transforms/Instrumentation/IndirectCallPromotion.cpp
+++ b/llvm/lib/Transforms/Instrumentation/IndirectCallPromotion.cpp
@@ -943,14 +943,16 @@ bool MemOPSizeOpt::perform(MemIntrinsic *MI) {
   BasicBlock *BB = MI->getParent();
   DEBUG(dbgs() << "\n\n== Basic Block Before ==\n");
   DEBUG(dbgs() << *BB << "\n");
+  auto OrigBBFreq = BFI.getBlockFreq(BB);
 
   BasicBlock *DefaultBB = SplitBlock(BB, MI);
   BasicBlock::iterator It(*MI);
   ++It;
   assert(It != DefaultBB->end());
   BasicBlock *MergeBB = SplitBlock(DefaultBB, &(*It));
-  DefaultBB->setName("MemOP.Default");
   MergeBB->setName("MemOP.Merge");
+  BFI.setBlockFreq(MergeBB, OrigBBFreq.getFrequency());
+  DefaultBB->setName("MemOP.Default");
 
   auto &Ctx = Func.getContext();
   IRBuilder<> IRB(BB);