[llvm] 2b8a09e - [MemorySSA] Update comment in PassBuilder

[Yuanfang Chen via llvm-commits]

Author: Yuanfang Chen
Date: 2020-06-26T14:55:31-07:00
New Revision: 2b8a09e1ed5c78cf5ae75fdcf55e1b5349a2d47c

URL: https://github.com/llvm/llvm-project/commit/2b8a09e1ed5c78cf5ae75fdcf55e1b5349a2d47c
DIFF: https://github.com/llvm/llvm-project/commit/2b8a09e1ed5c78cf5ae75fdcf55e1b5349a2d47c.diff

LOG: [MemorySSA] Update comment in PassBuilder

Is teaching the LoopFullUnrollPass to preserve MemorySSA very hard or
just impossible?

Reviewed By: asbirlea

Differential Revision: https://reviews.llvm.org/D82618

Added: 
    

Modified: 
    llvm/lib/Passes/PassBuilder.cpp

Removed: 
    


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diff  --git a/llvm/lib/Passes/PassBuilder.cpp b/llvm/lib/Passes/PassBuilder.cpp
index d1900ab31856..7bdeb4d3a028 100644
--- a/llvm/lib/Passes/PassBuilder.cpp
+++ b/llvm/lib/Passes/PassBuilder.cpp
@@ -508,8 +508,7 @@ FunctionPassManager PassBuilder::buildO1FunctionSimplificationPipeline(
       std::move(LPM1), EnableMSSALoopDependency, DebugLogging));
   FPM.addPass(SimplifyCFGPass());
   FPM.addPass(InstCombinePass());
-  // The loop passes in LPM2 (IndVarSimplifyPass, LoopIdiomRecognizePass,
-  // LoopDeletionPass and LoopFullUnrollPass) do not preserve MemorySSA.
+  // The loop passes in LPM2 (LoopFullUnrollPass) do not preserve MemorySSA.
   // *All* loop passes must preserve it, in order to be able to use it.
   FPM.addPass(createFunctionToLoopPassAdaptor(
       std::move(LPM2), /*UseMemorySSA=*/false, DebugLogging));