[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/unittests/Analysis/BasicAliasAnalysisTest.cpp b/llvm/unittests/Analysis/BasicAliasAnalysisTest.cpp
index 068774c..f69d2d1 100644
--- a/llvm/unittests/Analysis/BasicAliasAnalysisTest.cpp
+++ b/llvm/unittests/Analysis/BasicAliasAnalysisTest.cpp
@@ -44,17 +44,19 @@
     DominatorTree DT;
     AssumptionCache AC;
     BasicAAResult BAA;
+    AAQueryInfo AAQI;
 
     TestAnalyses(BasicAATest &Test)
-        : DT(*Test.F), AC(*Test.F), BAA(Test.DL, *Test.F, Test.TLI, AC, &DT) {}
+        : DT(*Test.F), AC(*Test.F), BAA(Test.DL, *Test.F, Test.TLI, AC, &DT),
+          AAQI() {}
   };
 
   llvm::Optional<TestAnalyses> Analyses;
 
-  BasicAAResult &setupAnalyses() {
+  TestAnalyses &setupAnalyses() {
     assert(F);
     Analyses.emplace(*this);
-    return Analyses->BAA;
+    return Analyses.getValue();
   }
 
 public:
@@ -83,15 +85,17 @@
   GlobalPtr->setLinkage(GlobalValue::LinkageTypes::InternalLinkage);
   GlobalPtr->setInitializer(B.getInt8(0));
 
-  BasicAAResult &BasicAA = setupAnalyses();
+  auto &AllAnalyses = setupAnalyses();
+  BasicAAResult &BasicAA = AllAnalyses.BAA;
+  AAQueryInfo &AAQI = AllAnalyses.AAQI;
   ASSERT_EQ(
       BasicAA.alias(MemoryLocation(IncomingI32Ptr, LocationSize::precise(4)),
-                    MemoryLocation(GlobalPtr, LocationSize::precise(1))),
+                    MemoryLocation(GlobalPtr, LocationSize::precise(1)), AAQI),
       AliasResult::NoAlias);
 
   ASSERT_EQ(
       BasicAA.alias(MemoryLocation(IncomingI32Ptr, LocationSize::upperBound(4)),
-                    MemoryLocation(GlobalPtr, LocationSize::precise(1))),
+                    MemoryLocation(GlobalPtr, LocationSize::precise(1)), AAQI),
       AliasResult::MayAlias);
 }
 
@@ -110,14 +114,18 @@
   auto *I8AtUncertainOffset =
       cast<GetElementPtrInst>(B.CreateGEP(B.getInt8Ty(), I8, ArbitraryI32));
 
-  BasicAAResult &BasicAA = setupAnalyses();
+  auto &AllAnalyses = setupAnalyses();
+  BasicAAResult &BasicAA = AllAnalyses.BAA;
+  AAQueryInfo &AAQI = AllAnalyses.AAQI;
   ASSERT_EQ(BasicAA.alias(
                 MemoryLocation(I8, LocationSize::precise(2)),
-                MemoryLocation(I8AtUncertainOffset, LocationSize::precise(1))),
+                MemoryLocation(I8AtUncertainOffset, LocationSize::precise(1)),
+                AAQI),
             AliasResult::PartialAlias);
 
   ASSERT_EQ(BasicAA.alias(
                 MemoryLocation(I8, LocationSize::upperBound(2)),
-                MemoryLocation(I8AtUncertainOffset, LocationSize::precise(1))),
+                MemoryLocation(I8AtUncertainOffset, LocationSize::precise(1)),
+                AAQI),
             AliasResult::MayAlias);
 }