From 47be3618f189879a22ceb060548a6a47d124f3f7 Mon Sep 17 00:00:00 2001
From: Hal Finkel <hfinkel@anl.gov>
Date: Fri, 11 Dec 2015 17:46:01 +0000
Subject: [PATCH] AlignmentFromAssumptions and SLPVectorizer preserves AA and
 GlobalsAA

GlobalsAA's assumptions that passes do not escape globals not previously
escaped is not violated by AlignmentFromAssumptions and SLPVectorizer. Marking
them as such allows GlobalsAA to be preserved until GVN in the LTO pipeline.

http://lists.llvm.org/pipermail/llvm-dev/2015-December/092972.html

Patch by Vaivaswatha Nagaraj!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255348 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Transforms/Scalar/AlignmentFromAssumptions.cpp | 4 ++++
 lib/Transforms/Vectorize/SLPVectorizer.cpp         | 3 +++
 2 files changed, 7 insertions(+)

diff --git a/lib/Transforms/Scalar/AlignmentFromAssumptions.cpp b/lib/Transforms/Scalar/AlignmentFromAssumptions.cpp
index a13e552cbd0..79cd1c0eaaa 100644
--- a/lib/Transforms/Scalar/AlignmentFromAssumptions.cpp
+++ b/lib/Transforms/Scalar/AlignmentFromAssumptions.cpp
@@ -21,6 +21,8 @@
 #include "llvm/Transforms/Scalar.h"
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/Statistic.h"
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/GlobalsModRef.h"
 #include "llvm/Analysis/AssumptionCache.h"
 #include "llvm/Analysis/LoopInfo.h"
 #include "llvm/Analysis/ScalarEvolution.h"
@@ -58,6 +60,8 @@ struct AlignmentFromAssumptions : public FunctionPass {
     AU.addRequired<DominatorTreeWrapperPass>();
 
     AU.setPreservesCFG();
+    AU.addPreserved<AAResultsWrapperPass>();
+    AU.addPreserved<GlobalsAAWrapperPass>();
     AU.addPreserved<LoopInfoWrapperPass>();
     AU.addPreserved<DominatorTreeWrapperPass>();
     AU.addPreserved<ScalarEvolutionWrapperPass>();
diff --git a/lib/Transforms/Vectorize/SLPVectorizer.cpp b/lib/Transforms/Vectorize/SLPVectorizer.cpp
index ad28a72deee..dead6e181c4 100644
--- a/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/lib/Transforms/Vectorize/SLPVectorizer.cpp
@@ -22,6 +22,7 @@
 #include "llvm/ADT/SetVector.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/GlobalsModRef.h"
 #include "llvm/Analysis/AssumptionCache.h"
 #include "llvm/Analysis/CodeMetrics.h"
 #include "llvm/Analysis/LoopInfo.h"
@@ -3235,6 +3236,8 @@ struct SLPVectorizer : public FunctionPass {
     AU.addRequired<DominatorTreeWrapperPass>();
     AU.addPreserved<LoopInfoWrapperPass>();
     AU.addPreserved<DominatorTreeWrapperPass>();
+    AU.addPreserved<AAResultsWrapperPass>();
+    AU.addPreserved<GlobalsAAWrapperPass>();
     AU.setPreservesCFG();
   }
 
-- 
2.11.0