[llvm] r261302 - [AA] Preserve the AA results wrapper pass as well as BasicAA in a few

[Chandler Carruth via llvm-commits]

Author: chandlerc
Date: Thu Feb 18 21:12:14 2016
New Revision: 261302

URL: http://llvm.org/viewvc/llvm-project?rev=261302&view=rev
Log:
[AA] Preserve the AA results wrapper pass as well as BasicAA in a few
more places to prevent gratuitous re-"runs" of these passes.

The passes themselves don't do any work when run, but we keep spending
time scheduling and running these needlessly when we really don't need
to do so.

This is the first patch towards fixing the really horrible loop pass
pipeline fragmentation pointed out by Sanjoy in PR24804.

Modified:
    llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp
    llvm/trunk/lib/Transforms/Utils/LCSSA.cpp

Modified: llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp?rev=261302&r1=261301&r2=261302&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp (original)
+++ llvm/trunk/lib/Transforms/InstCombine/InstructionCombining.cpp Thu Feb 18 21:12:14 2016
@@ -39,7 +39,9 @@
 #include "llvm/ADT/SmallPtrSet.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/ADT/StringSwitch.h"
+#include "llvm/Analysis/AliasAnalysis.h"
 #include "llvm/Analysis/AssumptionCache.h"
+#include "llvm/Analysis/BasicAliasAnalysis.h"
 #include "llvm/Analysis/CFG.h"
 #include "llvm/Analysis/ConstantFolding.h"
 #include "llvm/Analysis/EHPersonalities.h"
@@ -3103,6 +3105,8 @@ void InstructionCombiningPass::getAnalys
   AU.addRequired<TargetLibraryInfoWrapperPass>();
   AU.addRequired<DominatorTreeWrapperPass>();
   AU.addPreserved<DominatorTreeWrapperPass>();
+  AU.addPreserved<AAResultsWrapperPass>();
+  AU.addPreserved<BasicAAWrapperPass>();
   AU.addPreserved<GlobalsAAWrapperPass>();
 }
 

Modified: llvm/trunk/lib/Transforms/Utils/LCSSA.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Utils/LCSSA.cpp?rev=261302&r1=261301&r2=261302&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Utils/LCSSA.cpp (original)
+++ llvm/trunk/lib/Transforms/Utils/LCSSA.cpp Thu Feb 18 21:12:14 2016
@@ -31,6 +31,7 @@
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/BasicAliasAnalysis.h"
 #include "llvm/Analysis/GlobalsModRef.h"
 #include "llvm/Analysis/LoopPass.h"
 #include "llvm/Analysis/ScalarEvolution.h"
@@ -298,6 +299,7 @@ struct LCSSA : public FunctionPass {
     AU.addRequired<LoopInfoWrapperPass>();
     AU.addPreservedID(LoopSimplifyID);
     AU.addPreserved<AAResultsWrapperPass>();
+    AU.addPreserved<BasicAAWrapperPass>();
     AU.addPreserved<GlobalsAAWrapperPass>();
     AU.addPreserved<ScalarEvolutionWrapperPass>();
     AU.addPreserved<SCEVAAWrapperPass>();