[PATCH] D48914: [PGOMemOPSize] Preserve the DominatorTree

[Dave Green via Phabricator via llvm-commits]

dmgreen added inline comments.


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Comment at: lib/Transforms/Instrumentation/PGOMemOPSizeOpt.cpp:346
 
-  BasicBlock *DefaultBB = SplitBlock(BB, MI);
+  BasicBlock *DefaultBB = SplitBlock(BB, MI, &DT);
   BasicBlock::iterator It(*MI);
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Why not use DTU for the whole thing ;)


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Comment at: lib/Transforms/Instrumentation/PGOMemOPSizeOpt.cpp:432
   auto &ORE = getAnalysis<OptimizationRemarkEmitterWrapperPass>().getORE();
-  return PGOMemOPSizeOptImpl(F, BFI, ORE);
+  auto &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
+  return PGOMemOPSizeOptImpl(F, BFI, ORE, DT);
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We can use getAnalysisIfAvailable to only get the DT if it's already been created by some other pass in the pipeline. That way we can preserve it if it already exists, but don't have to recalculate it if not.


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Comment at: lib/Transforms/Instrumentation/PGOMemOPSizeOpt.cpp:443
   auto &ORE = FAM.getResult<OptimizationRemarkEmitterAnalysis>(F);
-  bool Changed = PGOMemOPSizeOptImpl(F, BFI, ORE);
+  auto &DT = FAM.getResult<DominatorTreeAnalysis>(F);
+  bool Changed = PGOMemOPSizeOptImpl(F, BFI, ORE, DT);
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I think the new pass manager equivalent to getAnalysisIfAvailable is getCachedResult<..>(F).


Repository:
  rL LLVM

https://reviews.llvm.org/D48914