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diff --git a/clang-r344140b/include/llvm/Transforms/Scalar/JumpThreading.h b/clang-r344140b/include/llvm/Transforms/Scalar/JumpThreading.h
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+++ b/clang-r344140b/include/llvm/Transforms/Scalar/JumpThreading.h
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+//===- JumpThreading.h - thread control through conditional BBs -*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+/// \file
+/// See the comments on JumpThreadingPass.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_SCALAR_JUMPTHREADING_H
+#define LLVM_TRANSFORMS_SCALAR_JUMPTHREADING_H
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/DenseSet.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Analysis/BlockFrequencyInfo.h"
+#include "llvm/Analysis/BranchProbabilityInfo.h"
+#include "llvm/IR/DomTreeUpdater.h"
+#include "llvm/IR/ValueHandle.h"
+#include <memory>
+#include <utility>
+
+namespace llvm {
+
+class BasicBlock;
+class BinaryOperator;
+class BranchInst;
+class CmpInst;
+class Constant;
+class DomTreeUpdater;
+class Function;
+class Instruction;
+class IntrinsicInst;
+class LazyValueInfo;
+class LoadInst;
+class PHINode;
+class TargetLibraryInfo;
+class Value;
+
+/// A private "module" namespace for types and utilities used by
+/// JumpThreading.
+/// These are implementation details and should not be used by clients.
+namespace jumpthreading {
+
+// These are at global scope so static functions can use them too.
+using PredValueInfo = SmallVectorImpl<std::pair<Constant *, BasicBlock *>>;
+using PredValueInfoTy = SmallVector<std::pair<Constant *, BasicBlock *>, 8>;
+
+// This is used to keep track of what kind of constant we're currently hoping
+// to find.
+enum ConstantPreference { WantInteger, WantBlockAddress };
+
+} // end namespace jumpthreading
+
+/// This pass performs 'jump threading', which looks at blocks that have
+/// multiple predecessors and multiple successors.  If one or more of the
+/// predecessors of the block can be proven to always jump to one of the
+/// successors, we forward the edge from the predecessor to the successor by
+/// duplicating the contents of this block.
+///
+/// An example of when this can occur is code like this:
+///
+///   if () { ...
+///     X = 4;
+///   }
+///   if (X < 3) {
+///
+/// In this case, the unconditional branch at the end of the first if can be
+/// revectored to the false side of the second if.
+class JumpThreadingPass : public PassInfoMixin<JumpThreadingPass> {
+  TargetLibraryInfo *TLI;
+  LazyValueInfo *LVI;
+  AliasAnalysis *AA;
+  DomTreeUpdater *DTU;
+  std::unique_ptr<BlockFrequencyInfo> BFI;
+  std::unique_ptr<BranchProbabilityInfo> BPI;
+  bool HasProfileData = false;
+  bool HasGuards = false;
+#ifdef NDEBUG
+  SmallPtrSet<const BasicBlock *, 16> LoopHeaders;
+#else
+  SmallSet<AssertingVH<const BasicBlock>, 16> LoopHeaders;
+#endif
+  DenseSet<std::pair<Value *, BasicBlock *>> RecursionSet;
+
+  unsigned BBDupThreshold;
+
+  // RAII helper for updating the recursion stack.
+  struct RecursionSetRemover {
+    DenseSet<std::pair<Value *, BasicBlock *>> &TheSet;
+    std::pair<Value *, BasicBlock *> ThePair;
+
+    RecursionSetRemover(DenseSet<std::pair<Value *, BasicBlock *>> &S,
+                        std::pair<Value *, BasicBlock *> P)
+        : TheSet(S), ThePair(P) {}
+
+    ~RecursionSetRemover() { TheSet.erase(ThePair); }
+  };
+
+public:
+  JumpThreadingPass(int T = -1);
+
+  // Glue for old PM.
+  bool runImpl(Function &F, TargetLibraryInfo *TLI_, LazyValueInfo *LVI_,
+               AliasAnalysis *AA_, DomTreeUpdater *DTU_, bool HasProfileData_,
+               std::unique_ptr<BlockFrequencyInfo> BFI_,
+               std::unique_ptr<BranchProbabilityInfo> BPI_);
+
+  PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
+
+  void releaseMemory() {
+    BFI.reset();
+    BPI.reset();
+  }
+
+  void FindLoopHeaders(Function &F);
+  bool ProcessBlock(BasicBlock *BB);
+  bool ThreadEdge(BasicBlock *BB, const SmallVectorImpl<BasicBlock *> &PredBBs,
+                  BasicBlock *SuccBB);
+  bool DuplicateCondBranchOnPHIIntoPred(
+      BasicBlock *BB, const SmallVectorImpl<BasicBlock *> &PredBBs);
+
+  bool
+  ComputeValueKnownInPredecessors(Value *V, BasicBlock *BB,
+                                  jumpthreading::PredValueInfo &Result,
+                                  jumpthreading::ConstantPreference Preference,
+                                  Instruction *CxtI = nullptr);
+  bool ProcessThreadableEdges(Value *Cond, BasicBlock *BB,
+                              jumpthreading::ConstantPreference Preference,
+                              Instruction *CxtI = nullptr);
+
+  bool ProcessBranchOnPHI(PHINode *PN);
+  bool ProcessBranchOnXOR(BinaryOperator *BO);
+  bool ProcessImpliedCondition(BasicBlock *BB);
+
+  bool SimplifyPartiallyRedundantLoad(LoadInst *LI);
+  bool TryToUnfoldSelect(CmpInst *CondCmp, BasicBlock *BB);
+  bool TryToUnfoldSelectInCurrBB(BasicBlock *BB);
+
+  bool ProcessGuards(BasicBlock *BB);
+  bool ThreadGuard(BasicBlock *BB, IntrinsicInst *Guard, BranchInst *BI);
+
+private:
+  BasicBlock *SplitBlockPreds(BasicBlock *BB, ArrayRef<BasicBlock *> Preds,
+                              const char *Suffix);
+  void UpdateBlockFreqAndEdgeWeight(BasicBlock *PredBB, BasicBlock *BB,
+                                    BasicBlock *NewBB, BasicBlock *SuccBB);
+  /// Check if the block has profile metadata for its outgoing edges.
+  bool doesBlockHaveProfileData(BasicBlock *BB);
+};
+
+} // end namespace llvm
+
+#endif // LLVM_TRANSFORMS_SCALAR_JUMPTHREADING_H