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diff --git a/linux-x64/clang/include/llvm/Analysis/BlockFrequencyInfo.h b/linux-x64/clang/include/llvm/Analysis/BlockFrequencyInfo.h
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+//===- BlockFrequencyInfo.h - Block Frequency Analysis ----------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Loops should be simplified before this analysis.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_BLOCKFREQUENCYINFO_H
+#define LLVM_ANALYSIS_BLOCKFREQUENCYINFO_H
+
+#include "llvm/ADT/Optional.h"
+#include "llvm/IR/PassManager.h"
+#include "llvm/Pass.h"
+#include "llvm/Support/BlockFrequency.h"
+#include <cstdint>
+#include <memory>
+
+namespace llvm {
+
+class BasicBlock;
+class BranchProbabilityInfo;
+class Function;
+class LoopInfo;
+class Module;
+class raw_ostream;
+template <class BlockT> class BlockFrequencyInfoImpl;
+
+enum PGOViewCountsType { PGOVCT_None, PGOVCT_Graph, PGOVCT_Text };
+
+/// BlockFrequencyInfo pass uses BlockFrequencyInfoImpl implementation to
+/// estimate IR basic block frequencies.
+class BlockFrequencyInfo {
+  using ImplType = BlockFrequencyInfoImpl<BasicBlock>;
+
+  std::unique_ptr<ImplType> BFI;
+
+public:
+  BlockFrequencyInfo();
+  BlockFrequencyInfo(const Function &F, const BranchProbabilityInfo &BPI,
+                     const LoopInfo &LI);
+  BlockFrequencyInfo(const BlockFrequencyInfo &) = delete;
+  BlockFrequencyInfo &operator=(const BlockFrequencyInfo &) = delete;
+  BlockFrequencyInfo(BlockFrequencyInfo &&Arg);
+  BlockFrequencyInfo &operator=(BlockFrequencyInfo &&RHS);
+  ~BlockFrequencyInfo();
+
+  /// Handle invalidation explicitly.
+  bool invalidate(Function &F, const PreservedAnalyses &PA,
+                  FunctionAnalysisManager::Invalidator &);
+
+  const Function *getFunction() const;
+  const BranchProbabilityInfo *getBPI() const;
+  void view() const;
+
+  /// getblockFreq - Return block frequency. Return 0 if we don't have the
+  /// information. Please note that initial frequency is equal to ENTRY_FREQ. It
+  /// means that we should not rely on the value itself, but only on the
+  /// comparison to the other block frequencies. We do this to avoid using of
+  /// floating points.
+  BlockFrequency getBlockFreq(const BasicBlock *BB) const;
+
+  /// \brief Returns the estimated profile count of \p BB.
+  /// This computes the relative block frequency of \p BB and multiplies it by
+  /// the enclosing function's count (if available) and returns the value.
+  Optional<uint64_t> getBlockProfileCount(const BasicBlock *BB) const;
+
+  /// \brief Returns the estimated profile count of \p Freq.
+  /// This uses the frequency \p Freq and multiplies it by
+  /// the enclosing function's count (if available) and returns the value.
+  Optional<uint64_t> getProfileCountFromFreq(uint64_t Freq) const;
+
+  /// \brief Returns true if \p BB is an irreducible loop header
+  /// block. Otherwise false.
+  bool isIrrLoopHeader(const BasicBlock *BB);
+
+  // Set the frequency of the given basic block.
+  void setBlockFreq(const BasicBlock *BB, uint64_t Freq);
+
+  /// Set the frequency of \p ReferenceBB to \p Freq and scale the frequencies
+  /// of the blocks in \p BlocksToScale such that their frequencies relative
+  /// to \p ReferenceBB remain unchanged.
+  void setBlockFreqAndScale(const BasicBlock *ReferenceBB, uint64_t Freq,
+                            SmallPtrSetImpl<BasicBlock *> &BlocksToScale);
+
+  /// calculate - compute block frequency info for the given function.
+  void calculate(const Function &F, const BranchProbabilityInfo &BPI,
+                 const LoopInfo &LI);
+
+  // Print the block frequency Freq to OS using the current functions entry
+  // frequency to convert freq into a relative decimal form.
+  raw_ostream &printBlockFreq(raw_ostream &OS, const BlockFrequency Freq) const;
+
+  // Convenience method that attempts to look up the frequency associated with
+  // BB and print it to OS.
+  raw_ostream &printBlockFreq(raw_ostream &OS, const BasicBlock *BB) const;
+
+  uint64_t getEntryFreq() const;
+  void releaseMemory();
+  void print(raw_ostream &OS) const;
+};
+
+/// \brief Analysis pass which computes \c BlockFrequencyInfo.
+class BlockFrequencyAnalysis
+    : public AnalysisInfoMixin<BlockFrequencyAnalysis> {
+  friend AnalysisInfoMixin<BlockFrequencyAnalysis>;
+
+  static AnalysisKey Key;
+
+public:
+  /// \brief Provide the result type for this analysis pass.
+  using Result = BlockFrequencyInfo;
+
+  /// \brief Run the analysis pass over a function and produce BFI.
+  Result run(Function &F, FunctionAnalysisManager &AM);
+};
+
+/// \brief Printer pass for the \c BlockFrequencyInfo results.
+class BlockFrequencyPrinterPass
+    : public PassInfoMixin<BlockFrequencyPrinterPass> {
+  raw_ostream &OS;
+
+public:
+  explicit BlockFrequencyPrinterPass(raw_ostream &OS) : OS(OS) {}
+
+  PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
+};
+
+/// \brief Legacy analysis pass which computes \c BlockFrequencyInfo.
+class BlockFrequencyInfoWrapperPass : public FunctionPass {
+  BlockFrequencyInfo BFI;
+
+public:
+  static char ID;
+
+  BlockFrequencyInfoWrapperPass();
+  ~BlockFrequencyInfoWrapperPass() override;
+
+  BlockFrequencyInfo &getBFI() { return BFI; }
+  const BlockFrequencyInfo &getBFI() const { return BFI; }
+
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+
+  bool runOnFunction(Function &F) override;
+  void releaseMemory() override;
+  void print(raw_ostream &OS, const Module *M) const override;
+};
+
+} // end namespace llvm
+
+#endif // LLVM_ANALYSIS_BLOCKFREQUENCYINFO_H