[PATCH] D74809: [MBP][X86] Include static prof data when collecting loop BBs

[David Li via Phabricator via llvm-commits]

davidxl added inline comments.


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Comment at: llvm/lib/CodeGen/MachineBlockPlacement.cpp:2516
+  if (F->getFunction().hasProfileData() || ForceLoopColdBlock ||
+      L.hasStaticProfInfo()) {
     BlockFrequency LoopFreq(0);
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The check here seems too weak.  One branch in the loop has user annotation does not mean other branch probablity data can be trusted.  More sophisticated analysis is needed.


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Comment at: llvm/lib/CodeGen/MachineLoopInfo.cpp:114
 
+bool MachineLoop::hasStaticProfInfo() const {
+  return llvm::any_of(blocks(), [](const MachineBasicBlock *MBB){
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 Note that with PGO is on, the branches are also annotated with MD_prof meta data. In other words, you will also need to check fhat the function entry does not have profile count.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D74809/new/

https://reviews.llvm.org/D74809