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!

llvm-svn: 255348

2 files changed, 7 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Scalar/AlignmentFromAssumptions.cpp b/llvm/lib/Transforms/Scalar/AlignmentFromAssumptions.cpp
index a13e552cbd0..79cd1c0eaaa 100644
--- a/llvm/lib/Transforms/Scalar/AlignmentFromAssumptions.cpp
+++ b/llvm/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/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp b/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
index ad28a72deee..dead6e181c4 100644
--- a/llvm/lib/Transforms/Vectorize/SLPVectorizer.cpp
+++ b/llvm/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();
   }