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diff --git a/include/llvm/Analysis/CFLAliasAnalysis.h b/include/llvm/Analysis/CFLAliasAnalysis.h
new file mode 100644
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+++ b/include/llvm/Analysis/CFLAliasAnalysis.h
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+//===- CFLAliasAnalysis.h - CFL-Based Alias Analysis Interface ---*- 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_CFLALIASANALYSIS_H
+#define LLVM_ANALYSIS_CFLALIASANALYSIS_H
+
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/None.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Module.h"
+#include "llvm/IR/ValueHandle.h"
+#include "llvm/Pass.h"
+#include <forward_list>
+
+namespace llvm {
+
+class CFLAAResult : public AAResultBase<CFLAAResult> {
+  friend AAResultBase<CFLAAResult>;
+
+  struct FunctionInfo;
+
+public:
+  explicit CFLAAResult(const TargetLibraryInfo &TLI);
+  CFLAAResult(CFLAAResult &&Arg);
+
+  /// 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; }
+
+  /// \brief Inserts the given Function into the cache.
+  void scan(Function *Fn);
+
+  void evict(Function *Fn);
+
+  /// \brief Ensures that the given function is available in the cache.
+  /// Returns the appropriate entry from the cache.
+  const Optional<FunctionInfo> &ensureCached(Function *Fn);
+
+  AliasResult query(const MemoryLocation &LocA, const MemoryLocation &LocB);
+
+  AliasResult alias(const MemoryLocation &LocA, const MemoryLocation &LocB) {
+    if (LocA.Ptr == LocB.Ptr) {
+      if (LocA.Size == LocB.Size) {
+        return MustAlias;
+      } else {
+        return PartialAlias;
+      }
+    }
+
+    // Comparisons between global variables and other constants should be
+    // handled by BasicAA.
+    // TODO: ConstantExpr handling -- CFLAA may report NoAlias when comparing
+    // a GlobalValue and ConstantExpr, but every query needs to have at least
+    // one Value tied to a Function, and neither GlobalValues nor ConstantExprs
+    // are.
+    if (isa<Constant>(LocA.Ptr) && isa<Constant>(LocB.Ptr)) {
+      return AAResultBase::alias(LocA, LocB);
+    }
+
+    AliasResult QueryResult = query(LocA, LocB);
+    if (QueryResult == MayAlias)
+      return AAResultBase::alias(LocA, LocB);
+
+    return QueryResult;
+  }
+
+private:
+  struct FunctionHandle final : public CallbackVH {
+    FunctionHandle(Function *Fn, CFLAAResult *Result)
+        : CallbackVH(Fn), Result(Result) {
+      assert(Fn != nullptr);
+      assert(Result != nullptr);
+    }
+
+    void deleted() override { removeSelfFromCache(); }
+    void allUsesReplacedWith(Value *) override { removeSelfFromCache(); }
+
+  private:
+    CFLAAResult *Result;
+
+    void removeSelfFromCache() {
+      assert(Result != nullptr);
+      auto *Val = getValPtr();
+      Result->evict(cast<Function>(Val));
+      setValPtr(nullptr);
+    }
+  };
+
+  /// \brief Cached mapping of Functions to their StratifiedSets.
+  /// If a function's sets are currently being built, it is marked
+  /// in the cache as an Optional without a value. This way, if we
+  /// have any kind of recursion, it is discernable from a function
+  /// that simply has empty sets.
+  DenseMap<Function *, Optional<FunctionInfo>> Cache;
+  std::forward_list<FunctionHandle> Handles;
+
+  FunctionInfo buildSetsFrom(Function *F);
+};
+
+/// Analysis pass providing a never-invalidated alias analysis result.
+///
+/// FIXME: We really should refactor CFL to use the analysis more heavily, and
+/// in particular to leverage invalidation to trigger re-computation of sets.
+class CFLAA {
+public:
+  typedef CFLAAResult Result;
+
+  /// \brief Opaque, unique identifier for this analysis pass.
+  static void *ID() { return (void *)&PassID; }
+
+  CFLAAResult run(Function &F, AnalysisManager<Function> *AM);
+
+  /// \brief Provide access to a name for this pass for debugging purposes.
+  static StringRef name() { return "CFLAA"; }
+
+private:
+  static char PassID;
+};
+
+/// Legacy wrapper pass to provide the CFLAAResult object.
+class CFLAAWrapperPass : public ImmutablePass {
+  std::unique_ptr<CFLAAResult> Result;
+
+public:
+  static char ID;
+
+  CFLAAWrapperPass();
+
+  CFLAAResult &getResult() { return *Result; }
+  const CFLAAResult &getResult() const { return *Result; }
+
+  bool doInitialization(Module &M) override;
+  bool doFinalization(Module &M) override;
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+};
+
+//===--------------------------------------------------------------------===//
+//
+// createCFLAAWrapperPass - This pass implements a set-based approach to
+// alias analysis.
+//
+ImmutablePass *createCFLAAWrapperPass();
+}
+
+#endif