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diff --git a/linux-x64/clang/include/llvm/Analysis/LazyBlockFrequencyInfo.h b/linux-x64/clang/include/llvm/Analysis/LazyBlockFrequencyInfo.h
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+//===- LazyBlockFrequencyInfo.h - Lazy 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.
+//
+//===----------------------------------------------------------------------===//
+//
+// This is an alternative analysis pass to BlockFrequencyInfoWrapperPass.  The
+// difference is that with this pass the block frequencies are not computed when
+// the analysis pass is executed but rather when the BFI result is explicitly
+// requested by the analysis client.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_LAZYBLOCKFREQUENCYINFO_H
+#define LLVM_ANALYSIS_LAZYBLOCKFREQUENCYINFO_H
+
+#include "llvm/Analysis/BlockFrequencyInfo.h"
+#include "llvm/Analysis/LazyBranchProbabilityInfo.h"
+#include "llvm/Pass.h"
+
+namespace llvm {
+class AnalysisUsage;
+class BranchProbabilityInfo;
+class Function;
+class LoopInfo;
+
+/// Wraps a BFI to allow lazy computation of the block frequencies.
+///
+/// A pass that only conditionally uses BFI can uncondtionally require the
+/// analysis without paying for the overhead if BFI doesn't end up being used.
+template <typename FunctionT, typename BranchProbabilityInfoPassT,
+          typename LoopInfoT, typename BlockFrequencyInfoT>
+class LazyBlockFrequencyInfo {
+public:
+  LazyBlockFrequencyInfo()
+      : Calculated(false), F(nullptr), BPIPass(nullptr), LI(nullptr) {}
+
+  /// Set up the per-function input.
+  void setAnalysis(const FunctionT *F, BranchProbabilityInfoPassT *BPIPass,
+                   const LoopInfoT *LI) {
+    this->F = F;
+    this->BPIPass = BPIPass;
+    this->LI = LI;
+  }
+
+  /// Retrieve the BFI with the block frequencies computed.
+  BlockFrequencyInfoT &getCalculated() {
+    if (!Calculated) {
+      assert(F && BPIPass && LI && "call setAnalysis");
+      BFI.calculate(
+          *F, BPIPassTrait<BranchProbabilityInfoPassT>::getBPI(BPIPass), *LI);
+      Calculated = true;
+    }
+    return BFI;
+  }
+
+  const BlockFrequencyInfoT &getCalculated() const {
+    return const_cast<LazyBlockFrequencyInfo *>(this)->getCalculated();
+  }
+
+  void releaseMemory() {
+    BFI.releaseMemory();
+    Calculated = false;
+    setAnalysis(nullptr, nullptr, nullptr);
+  }
+
+private:
+  BlockFrequencyInfoT BFI;
+  bool Calculated;
+  const FunctionT *F;
+  BranchProbabilityInfoPassT *BPIPass;
+  const LoopInfoT *LI;
+};
+
+/// \brief This is an alternative analysis pass to
+/// BlockFrequencyInfoWrapperPass.  The difference is that with this pass the
+/// block frequencies are not computed when the analysis pass is executed but
+/// rather when the BFI result is explicitly requested by the analysis client.
+///
+/// There are some additional requirements for any client pass that wants to use
+/// the analysis:
+///
+/// 1. The pass needs to initialize dependent passes with:
+///
+///   INITIALIZE_PASS_DEPENDENCY(LazyBFIPass)
+///
+/// 2. Similarly, getAnalysisUsage should call:
+///
+///   LazyBlockFrequencyInfoPass::getLazyBFIAnalysisUsage(AU)
+///
+/// 3. The computed BFI should be requested with
+///    getAnalysis<LazyBlockFrequencyInfoPass>().getBFI() before either LoopInfo
+///    or BPI could be invalidated for example by changing the CFG.
+///
+/// Note that it is expected that we wouldn't need this functionality for the
+/// new PM since with the new PM, analyses are executed on demand.
+
+class LazyBlockFrequencyInfoPass : public FunctionPass {
+private:
+  LazyBlockFrequencyInfo<Function, LazyBranchProbabilityInfoPass, LoopInfo,
+                         BlockFrequencyInfo>
+      LBFI;
+
+public:
+  static char ID;
+
+  LazyBlockFrequencyInfoPass();
+
+  /// \brief Compute and return the block frequencies.
+  BlockFrequencyInfo &getBFI() { return LBFI.getCalculated(); }
+
+  /// \brief Compute and return the block frequencies.
+  const BlockFrequencyInfo &getBFI() const { return LBFI.getCalculated(); }
+
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+
+  /// Helper for client passes to set up the analysis usage on behalf of this
+  /// pass.
+  static void getLazyBFIAnalysisUsage(AnalysisUsage &AU);
+
+  bool runOnFunction(Function &F) override;
+  void releaseMemory() override;
+  void print(raw_ostream &OS, const Module *M) const override;
+};
+
+/// \brief Helper for client passes to initialize dependent passes for LBFI.
+void initializeLazyBFIPassPass(PassRegistry &Registry);
+}
+#endif