[AliasAnalysis] Second prototype to cache BasicAA / anyAA state.

Summary:
Adding contained caching to AliasAnalysis. BasicAA is currently the only one using it.

AA changes:
- This patch is pulling the caches from BasicAAResults to AAResults, meaning the getModRefInfo call benefits from the IsCapturedCache as well when in "batch mode".
- All AAResultBase implementations add the QueryInfo member to all APIs. AAResults APIs maintain wrapper APIs such that all alias()/getModRefInfo call sites are unchanged.
- AA now provides a BatchAAResults type as a wrapper to AAResults. It keeps the AAResults instance and a QueryInfo instantiated to batch mode. It delegates all work to the AAResults instance with the batched QueryInfo. More API wrappers may be needed in BatchAAResults; only the minimum needed is currently added.

MemorySSA changes:
- All walkers are now templated on the AA used (AliasAnalysis=AAResults or BatchAAResults).
- At build time, we optimize uses; now we create a local walker (lives only as long as OptimizeUses does) using BatchAAResults.
- All Walkers have an internal AA and only use that now, never the AA in MemorySSA. The Walkers receive the AA they will use when built.

- The walker we use for queries after the build is instantiated on AliasAnalysis and is built after building MemorySSA and setting AA.
- All static methods doing walking are now templated on AliasAnalysisType if they are used both during build and after. If used only during build, the method now only takes a BatchAAResults. If used only after build, the method now takes an AliasAnalysis.

Subscribers: sanjoy, arsenm, jvesely, nhaehnle, jlebar, george.burgess.iv, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59315

llvm-svn: 356783
diff --git a/llvm/lib/Analysis/ScalarEvolutionAliasAnalysis.cpp b/llvm/lib/Analysis/ScalarEvolutionAliasAnalysis.cpp
index 4f66b4d..96da0a2 100644
--- a/llvm/lib/Analysis/ScalarEvolutionAliasAnalysis.cpp
+++ b/llvm/lib/Analysis/ScalarEvolutionAliasAnalysis.cpp
@@ -22,7 +22,7 @@
 using namespace llvm;
 
 AliasResult SCEVAAResult::alias(const MemoryLocation &LocA,
-                                const MemoryLocation &LocB) {
+                                const MemoryLocation &LocB, AAQueryInfo &AAQI) {
   // If either of the memory references is empty, it doesn't matter what the
   // pointer values are. This allows the code below to ignore this special
   // case.
@@ -85,11 +85,12 @@
                              AO ? AAMDNodes() : LocA.AATags),
               MemoryLocation(BO ? BO : LocB.Ptr,
                              BO ? LocationSize::unknown() : LocB.Size,
-                             BO ? AAMDNodes() : LocB.AATags)) == NoAlias)
+                             BO ? AAMDNodes() : LocB.AATags),
+              AAQI) == NoAlias)
       return NoAlias;
 
   // Forward the query to the next analysis.
-  return AAResultBase::alias(LocA, LocB);
+  return AAResultBase::alias(LocA, LocB, AAQI);
 }
 
 /// Given an expression, try to find a base value.