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diff --git a/include/llvm/Analysis/BasicAliasAnalysis.h b/include/llvm/Analysis/BasicAliasAnalysis.h
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+//===- BasicAliasAnalysis.h - Stateless, local Alias Analysis ---*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+/// \file
+/// This is the interface for LLVM's primary stateless and local alias analysis.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_BASICALIASANALYSIS_H
+#define LLVM_ANALYSIS_BASICALIASANALYSIS_H
+
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/AssumptionCache.h"
+#include "llvm/Analysis/TargetLibraryInfo.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/GetElementPtrTypeIterator.h"
+#include "llvm/IR/Instruction.h"
+#include "llvm/IR/LLVMContext.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/PassManager.h"
+#include "llvm/Support/ErrorHandling.h"
+
+namespace llvm {
+class AssumptionCache;
+class DominatorTree;
+class LoopInfo;
+
+/// This is the AA result object for the basic, local, and stateless alias
+/// analysis. It implements the AA query interface in an entirely stateless
+/// manner. As one consequence, it is never invalidated. While it does retain
+/// some storage, that is used as an optimization and not to preserve
+/// information from query to query.
+class BasicAAResult : public AAResultBase<BasicAAResult> {
+  friend AAResultBase<BasicAAResult>;
+
+  const DataLayout &DL;
+  AssumptionCache &AC;
+  DominatorTree *DT;
+  LoopInfo *LI;
+
+public:
+  BasicAAResult(const DataLayout &DL, const TargetLibraryInfo &TLI,
+                AssumptionCache &AC, DominatorTree *DT = nullptr,
+                LoopInfo *LI = nullptr)
+      : AAResultBase(TLI), DL(DL), AC(AC), DT(DT), LI(LI) {}
+
+  BasicAAResult(const BasicAAResult &Arg)
+      : AAResultBase(Arg), DL(Arg.DL), AC(Arg.AC), DT(Arg.DT), LI(Arg.LI) {}
+  BasicAAResult(BasicAAResult &&Arg)
+      : AAResultBase(std::move(Arg)), DL(Arg.DL), AC(Arg.AC), DT(Arg.DT),
+        LI(Arg.LI) {}
+
+  /// Handle invalidation events from the new pass manager.
+  ///
+  /// By definition, this result is stateless and so remains valid.
+  bool invalidate(Function &, const PreservedAnalyses &) { return false; }
+
+  AliasResult alias(const MemoryLocation &LocA, const MemoryLocation &LocB);
+
+  ModRefInfo getModRefInfo(ImmutableCallSite CS, const MemoryLocation &Loc);
+
+  ModRefInfo getModRefInfo(ImmutableCallSite CS1, ImmutableCallSite CS2);
+
+  /// Chases pointers until we find a (constant global) or not.
+  bool pointsToConstantMemory(const MemoryLocation &Loc, bool OrLocal);
+
+  /// Get the location associated with a pointer argument of a callsite.
+  ModRefInfo getArgModRefInfo(ImmutableCallSite CS, unsigned ArgIdx);
+
+  /// Returns the behavior when calling the given call site.
+  FunctionModRefBehavior getModRefBehavior(ImmutableCallSite CS);
+
+  /// Returns the behavior when calling the given function. For use when the
+  /// call site is not known.
+  FunctionModRefBehavior getModRefBehavior(const Function *F);
+
+private:
+  // A linear transformation of a Value; this class represents ZExt(SExt(V,
+  // SExtBits), ZExtBits) * Scale + Offset.
+  struct VariableGEPIndex {
+
+    // An opaque Value - we can't decompose this further.
+    const Value *V;
+
+    // We need to track what extensions we've done as we consider the same Value
+    // with different extensions as different variables in a GEP's linear
+    // expression;
+    // e.g.: if V == -1, then sext(x) != zext(x).
+    unsigned ZExtBits;
+    unsigned SExtBits;
+
+    int64_t Scale;
+
+    bool operator==(const VariableGEPIndex &Other) const {
+      return V == Other.V && ZExtBits == Other.ZExtBits &&
+             SExtBits == Other.SExtBits && Scale == Other.Scale;
+    }
+
+    bool operator!=(const VariableGEPIndex &Other) const {
+      return !operator==(Other);
+    }
+  };
+
+  /// Track alias queries to guard against recursion.
+  typedef std::pair<MemoryLocation, MemoryLocation> LocPair;
+  typedef SmallDenseMap<LocPair, AliasResult, 8> AliasCacheTy;
+  AliasCacheTy AliasCache;
+
+  /// Tracks phi nodes we have visited.
+  ///
+  /// When interpret "Value" pointer equality as value equality we need to make
+  /// sure that the "Value" is not part of a cycle. Otherwise, two uses could
+  /// come from different "iterations" of a cycle and see different values for
+  /// the same "Value" pointer.
+  ///
+  /// The following example shows the problem:
+  ///   %p = phi(%alloca1, %addr2)
+  ///   %l = load %ptr
+  ///   %addr1 = gep, %alloca2, 0, %l
+  ///   %addr2 = gep  %alloca2, 0, (%l + 1)
+  ///      alias(%p, %addr1) -> MayAlias !
+  ///   store %l, ...
+  SmallPtrSet<const BasicBlock *, 8> VisitedPhiBBs;
+
+  /// Tracks instructions visited by pointsToConstantMemory.
+  SmallPtrSet<const Value *, 16> Visited;
+
+  static const Value *
+  GetLinearExpression(const Value *V, APInt &Scale, APInt &Offset,
+                      unsigned &ZExtBits, unsigned &SExtBits,
+                      const DataLayout &DL, unsigned Depth, AssumptionCache *AC,
+                      DominatorTree *DT, bool &NSW, bool &NUW);
+
+  static const Value *
+  DecomposeGEPExpression(const Value *V, int64_t &BaseOffs,
+                         SmallVectorImpl<VariableGEPIndex> &VarIndices,
+                         bool &MaxLookupReached, const DataLayout &DL,
+                         AssumptionCache *AC, DominatorTree *DT);
+  /// \brief A Heuristic for aliasGEP that searches for a constant offset
+  /// between the variables.
+  ///
+  /// GetLinearExpression has some limitations, as generally zext(%x + 1)
+  /// != zext(%x) + zext(1) if the arithmetic overflows. GetLinearExpression
+  /// will therefore conservatively refuse to decompose these expressions.
+  /// However, we know that, for all %x, zext(%x) != zext(%x + 1), even if
+  /// the addition overflows.
+  bool
+  constantOffsetHeuristic(const SmallVectorImpl<VariableGEPIndex> &VarIndices,
+                          uint64_t V1Size, uint64_t V2Size, int64_t BaseOffset,
+                          AssumptionCache *AC, DominatorTree *DT);
+
+  bool isValueEqualInPotentialCycles(const Value *V1, const Value *V2);
+
+  void GetIndexDifference(SmallVectorImpl<VariableGEPIndex> &Dest,
+                          const SmallVectorImpl<VariableGEPIndex> &Src);
+
+  AliasResult aliasGEP(const GEPOperator *V1, uint64_t V1Size,
+                       const AAMDNodes &V1AAInfo, const Value *V2,
+                       uint64_t V2Size, const AAMDNodes &V2AAInfo,
+                       const Value *UnderlyingV1, const Value *UnderlyingV2);
+
+  AliasResult aliasPHI(const PHINode *PN, uint64_t PNSize,
+                       const AAMDNodes &PNAAInfo, const Value *V2,
+                       uint64_t V2Size, const AAMDNodes &V2AAInfo);
+
+  AliasResult aliasSelect(const SelectInst *SI, uint64_t SISize,
+                          const AAMDNodes &SIAAInfo, const Value *V2,
+                          uint64_t V2Size, const AAMDNodes &V2AAInfo);
+
+  AliasResult aliasCheck(const Value *V1, uint64_t V1Size, AAMDNodes V1AATag,
+                         const Value *V2, uint64_t V2Size, AAMDNodes V2AATag);
+};
+
+/// Analysis pass providing a never-invalidated alias analysis result.
+class BasicAA {
+public:
+  typedef BasicAAResult Result;
+
+  /// \brief Opaque, unique identifier for this analysis pass.
+  static void *ID() { return (void *)&PassID; }
+
+  BasicAAResult run(Function &F, AnalysisManager<Function> *AM);
+
+  /// \brief Provide access to a name for this pass for debugging purposes.
+  static StringRef name() { return "BasicAliasAnalysis"; }
+
+private:
+  static char PassID;
+};
+
+/// Legacy wrapper pass to provide the BasicAAResult object.
+class BasicAAWrapperPass : public FunctionPass {
+  std::unique_ptr<BasicAAResult> Result;
+
+  virtual void anchor();
+
+public:
+  static char ID;
+
+  BasicAAWrapperPass();
+
+  BasicAAResult &getResult() { return *Result; }
+  const BasicAAResult &getResult() const { return *Result; }
+
+  bool runOnFunction(Function &F) override;
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+};
+
+FunctionPass *createBasicAAWrapperPass();
+
+/// A helper for the legacy pass manager to create a \c BasicAAResult object
+/// populated to the best of our ability for a particular function when inside
+/// of a \c ModulePass or a \c CallGraphSCCPass.
+BasicAAResult createLegacyPMBasicAAResult(Pass &P, Function &F);
+}
+
+#endif