From f92109dc01b831304bedc990c41d8ea4bfd0a277 Mon Sep 17 00:00:00 2001
From: Alina Sbirlea <asbirlea@google.com>
Date: Sat, 17 Aug 2019 01:02:12 +0000
Subject: [PATCH] [MemorySSA] Loop passes should mark MSSA preserved when
 available.

This patch applies only to the new pass manager.
Currently, when MSSA Analysis is available, and pass to each loop pass, it will be preserved by that loop pass.
Hence, mark the analysis preserved based on that condition, vs the current `EnableMSSALoopDependency`. This leaves the global flag to affect only the entry point in the loop pass manager (in FunctionToLoopPassAdaptor).

llvm-svn: 369181
---
 llvm/lib/Transforms/Scalar/LICM.cpp               | 2 +-
 llvm/lib/Transforms/Scalar/LoopInstSimplify.cpp   | 2 +-
 llvm/lib/Transforms/Scalar/LoopRotation.cpp       | 2 +-
 llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp    | 4 ++--
 llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp | 2 +-
 5 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/llvm/lib/Transforms/Scalar/LICM.cpp b/llvm/lib/Transforms/Scalar/LICM.cpp
index 5015ca8..e0296fb 100644
--- a/llvm/lib/Transforms/Scalar/LICM.cpp
+++ b/llvm/lib/Transforms/Scalar/LICM.cpp
@@ -294,7 +294,7 @@ PreservedAnalyses LICMPass::run(Loop &L, LoopAnalysisManager &AM,
 
   PA.preserve<DominatorTreeAnalysis>();
   PA.preserve<LoopAnalysis>();
-  if (EnableMSSALoopDependency)
+  if (AR.MSSA)
     PA.preserve<MemorySSAAnalysis>();
 
   return PA;
diff --git a/llvm/lib/Transforms/Scalar/LoopInstSimplify.cpp b/llvm/lib/Transforms/Scalar/LoopInstSimplify.cpp
index 31191b5..c085d8f 100644
--- a/llvm/lib/Transforms/Scalar/LoopInstSimplify.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopInstSimplify.cpp
@@ -233,7 +233,7 @@ PreservedAnalyses LoopInstSimplifyPass::run(Loop &L, LoopAnalysisManager &AM,
 
   auto PA = getLoopPassPreservedAnalyses();
   PA.preserveSet<CFGAnalyses>();
-  if (EnableMSSALoopDependency)
+  if (AR.MSSA)
     PA.preserve<MemorySSAAnalysis>();
   return PA;
 }
diff --git a/llvm/lib/Transforms/Scalar/LoopRotation.cpp b/llvm/lib/Transforms/Scalar/LoopRotation.cpp
index e009947..95e2316 100644
--- a/llvm/lib/Transforms/Scalar/LoopRotation.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopRotation.cpp
@@ -55,7 +55,7 @@ PreservedAnalyses LoopRotatePass::run(Loop &L, LoopAnalysisManager &AM,
     AR.MSSA->verifyMemorySSA();
 
   auto PA = getLoopPassPreservedAnalyses();
-  if (EnableMSSALoopDependency)
+  if (AR.MSSA)
     PA.preserve<MemorySSAAnalysis>();
   return PA;
 }
diff --git a/llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp b/llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp
index 046f4c8..299f3fc 100644
--- a/llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp
+++ b/llvm/lib/Transforms/Scalar/LoopSimplifyCFG.cpp
@@ -690,7 +690,7 @@ PreservedAnalyses LoopSimplifyCFGPass::run(Loop &L, LoopAnalysisManager &AM,
                                            LoopStandardAnalysisResults &AR,
                                            LPMUpdater &LPMU) {
   Optional<MemorySSAUpdater> MSSAU;
-  if (EnableMSSALoopDependency && AR.MSSA)
+  if (AR.MSSA)
     MSSAU = MemorySSAUpdater(AR.MSSA);
   bool DeleteCurrentLoop = false;
   if (!simplifyLoopCFG(L, AR.DT, AR.LI, AR.SE,
@@ -702,7 +702,7 @@ PreservedAnalyses LoopSimplifyCFGPass::run(Loop &L, LoopAnalysisManager &AM,
     LPMU.markLoopAsDeleted(L, "loop-simplifycfg");
 
   auto PA = getLoopPassPreservedAnalyses();
-  if (EnableMSSALoopDependency)
+  if (AR.MSSA)
     PA.preserve<MemorySSAAnalysis>();
   return PA;
 }
diff --git a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
index aeac6f5..4e7abfc 100644
--- a/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
+++ b/llvm/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
@@ -2880,7 +2880,7 @@ PreservedAnalyses SimpleLoopUnswitchPass::run(Loop &L, LoopAnalysisManager &AM,
   assert(AR.DT.verify(DominatorTree::VerificationLevel::Fast));
 
   auto PA = getLoopPassPreservedAnalyses();
-  if (EnableMSSALoopDependency)
+  if (AR.MSSA)
     PA.preserve<MemorySSAAnalysis>();
   return PA;
 }
-- 
2.7.4