[llvm] r367594 - [MemorySSA] Set LoopSimplify to preserve MemorySSA in the NPM, if analysis exists.

[Alina Sbirlea via llvm-commits]

Author: asbirlea
Date: Thu Aug  1 11:28:28 2019
New Revision: 367594

URL: http://llvm.org/viewvc/llvm-project?rev=367594&view=rev
Log:
[MemorySSA] Set LoopSimplify to preserve MemorySSA in the NPM, if analysis exists.

Summary:
LoopSimplify is preserved in the legacy pass manager, but not in the new pass manager.
Update LoopSimplify to preserve MemorySSA conditionally when the analysis is available (same behavior as the legacy pass manager).

Reviewers: chandlerc

Subscribers: mehdi_amini, jlebar, Prazek, george.burgess.iv, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D65418

Modified:
    llvm/trunk/lib/Transforms/Utils/LoopSimplify.cpp
    llvm/trunk/unittests/Transforms/Scalar/LoopPassManagerTest.cpp

Modified: llvm/trunk/lib/Transforms/Utils/LoopSimplify.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/LoopSimplify.cpp?rev=367594&r1=367593&r2=367594&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/LoopSimplify.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/LoopSimplify.cpp Thu Aug  1 11:28:28 2019
@@ -835,12 +835,19 @@ PreservedAnalyses LoopSimplifyPass::run(
   DominatorTree *DT = &AM.getResult<DominatorTreeAnalysis>(F);
   ScalarEvolution *SE = AM.getCachedResult<ScalarEvolutionAnalysis>(F);
   AssumptionCache *AC = &AM.getResult<AssumptionAnalysis>(F);
+  auto *MSSAAnalysis = AM.getCachedResult<MemorySSAAnalysis>(F);
+  std::unique_ptr<MemorySSAUpdater> MSSAU;
+  if (MSSAAnalysis) {
+    auto *MSSA = &MSSAAnalysis->getMSSA();
+    MSSAU = make_unique<MemorySSAUpdater>(MSSA);
+  }
+
 
   // Note that we don't preserve LCSSA in the new PM, if you need it run LCSSA
-  // after simplifying the loops. MemorySSA is not preserved either.
+  // after simplifying the loops. MemorySSA is preserved if it exists.
   for (LoopInfo::iterator I = LI->begin(), E = LI->end(); I != E; ++I)
     Changed |=
-        simplifyLoop(*I, DT, LI, SE, AC, nullptr, /*PreserveLCSSA*/ false);
+        simplifyLoop(*I, DT, LI, SE, AC, MSSAU.get(), /*PreserveLCSSA*/ false);
 
   if (!Changed)
     return PreservedAnalyses::all();
@@ -853,6 +860,8 @@ PreservedAnalyses LoopSimplifyPass::run(
   PA.preserve<SCEVAA>();
   PA.preserve<ScalarEvolutionAnalysis>();
   PA.preserve<DependenceAnalysis>();
+  if (MSSAAnalysis)
+    PA.preserve<MemorySSAAnalysis>();
   // BPI maps conditional terminators to probabilities, LoopSimplify can insert
   // blocks, but it does so only by splitting existing blocks and edges. This
   // results in the interesting property that all new terminators inserted are

Modified: llvm/trunk/unittests/Transforms/Scalar/LoopPassManagerTest.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/unittests/Transforms/Scalar/LoopPassManagerTest.cpp?rev=367594&r1=367593&r2=367594&view=diff
==============================================================================
--- llvm/trunk/unittests/Transforms/Scalar/LoopPassManagerTest.cpp (original)
+++ llvm/trunk/unittests/Transforms/Scalar/LoopPassManagerTest.cpp Thu Aug  1 11:28:28 2019
@@ -293,8 +293,7 @@ public:
     // those.
     FAM.registerPass([&] { return AAManager(); });
     FAM.registerPass([&] { return AssumptionAnalysis(); });
-    if (EnableMSSALoopDependency)
-      FAM.registerPass([&] { return MemorySSAAnalysis(); });
+    FAM.registerPass([&] { return MemorySSAAnalysis(); });
     FAM.registerPass([&] { return ScalarEvolutionAnalysis(); });
     FAM.registerPass([&] { return TargetLibraryAnalysis(); });
     FAM.registerPass([&] { return TargetIRAnalysis(); });