From 35081ff9e6a05a72480b295cc800fbade873d316 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).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@369181 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Transforms/Scalar/LICM.cpp               | 2 +-
 lib/Transforms/Scalar/LoopInstSimplify.cpp   | 2 +-
 lib/Transforms/Scalar/LoopRotation.cpp       | 2 +-
 lib/Transforms/Scalar/LoopSimplifyCFG.cpp    | 4 ++--
 lib/Transforms/Scalar/SimpleLoopUnswitch.cpp | 2 +-
 5 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/lib/Transforms/Scalar/LICM.cpp b/lib/Transforms/Scalar/LICM.cpp
index 5015ca8dbb1..e0296fb58ea 100644
--- a/lib/Transforms/Scalar/LICM.cpp
+++ b/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/lib/Transforms/Scalar/LoopInstSimplify.cpp b/lib/Transforms/Scalar/LoopInstSimplify.cpp
index 31191b52895..c085d8ff5ac 100644
--- a/lib/Transforms/Scalar/LoopInstSimplify.cpp
+++ b/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/lib/Transforms/Scalar/LoopRotation.cpp b/lib/Transforms/Scalar/LoopRotation.cpp
index e009947690a..95e2316c20d 100644
--- a/lib/Transforms/Scalar/LoopRotation.cpp
+++ b/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/lib/Transforms/Scalar/LoopSimplifyCFG.cpp b/lib/Transforms/Scalar/LoopSimplifyCFG.cpp
index 046f4c8af49..299f3fc5fb1 100644
--- a/lib/Transforms/Scalar/LoopSimplifyCFG.cpp
+++ b/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/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp b/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
index aeac6f548b3..4e7abfc5bda 100644
--- a/lib/Transforms/Scalar/SimpleLoopUnswitch.cpp
+++ b/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;
 }
-- 
2.49.0