[llvm] f7ca542 - [LoopSimplifyCFG] Do not require MSSA. Continue to preserve if available.

[Alina Sbirlea via llvm-commits]

Author: Alina Sbirlea
Date: 2021-10-11T14:27:15-07:00
New Revision: f7ca54289c1466e47eb5e77a9e3f751f13223428

URL: https://github.com/llvm/llvm-project/commit/f7ca54289c1466e47eb5e77a9e3f751f13223428
DIFF: https://github.com/llvm/llvm-project/commit/f7ca54289c1466e47eb5e77a9e3f751f13223428.diff

LOG: [LoopSimplifyCFG] Do not require MSSA. Continue to preserve if available.

LoopSimplifyCFG does not need MSSA, but should preserve it if it's available.

This is a legacy PM change, aimed to denoise the test changes in D109958.

Differential Revision: https://reviews.llvm.org/D111578

Added: 
    

Modified: 
    llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp

Removed: 
    


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diff  --git a/llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp b/llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp
index 6fa736426e45..a87843d658a9 100644
--- a/llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp
@@ -733,19 +733,22 @@ class LoopSimplifyCFGLegacyPass : public LoopPass {
     DominatorTree &DT = getAnalysis<DominatorTreeWrapperPass>().getDomTree();
     LoopInfo &LI = getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
     ScalarEvolution &SE = getAnalysis<ScalarEvolutionWrapperPass>().getSE();
-    MemorySSA *MSSA = &getAnalysis<MemorySSAWrapperPass>().getMSSA();
-    MemorySSAUpdater MSSAU(MSSA);
-    if (VerifyMemorySSA)
-      MSSA->verifyMemorySSA();
+    auto *MSSAA = getAnalysisIfAvailable<MemorySSAWrapperPass>();
+    Optional<MemorySSAUpdater> MSSAU;
+    if (MSSAA)
+      MSSAU = MemorySSAUpdater(&MSSAA->getMSSA());
+    if (MSSAA && VerifyMemorySSA)
+      MSSAU->getMemorySSA()->verifyMemorySSA();
     bool DeleteCurrentLoop = false;
-    bool Changed = simplifyLoopCFG(*L, DT, LI, SE, &MSSAU, DeleteCurrentLoop);
+    bool Changed = simplifyLoopCFG(
+        *L, DT, LI, SE, MSSAU.hasValue() ? MSSAU.getPointer() : nullptr,
+        DeleteCurrentLoop);
     if (DeleteCurrentLoop)
       LPM.markLoopAsDeleted(*L);
     return Changed;
   }
 
   void getAnalysisUsage(AnalysisUsage &AU) const override {
-    AU.addRequired<MemorySSAWrapperPass>();
     AU.addPreserved<MemorySSAWrapperPass>();
     AU.addPreserved<DependenceAnalysisWrapperPass>();
     getLoopAnalysisUsage(AU);