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diff --git a/contrib/llvm-project/llvm/include/llvm/Analysis/LazyBranchProbabilityInfo.h b/contrib/llvm-project/llvm/include/llvm/Analysis/LazyBranchProbabilityInfo.h
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+//===- LazyBranchProbabilityInfo.h - Lazy Branch Probability ----*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This is an alternative analysis pass to BranchProbabilityInfoWrapperPass.
+// The difference is that with this pass the branch probabilities are not
+// computed when the analysis pass is executed but rather when the BPI results
+// is explicitly requested by the analysis client.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_LAZYBRANCHPROBABILITYINFO_H
+#define LLVM_ANALYSIS_LAZYBRANCHPROBABILITYINFO_H
+
+#include "llvm/Analysis/BranchProbabilityInfo.h"
+#include "llvm/Pass.h"
+
+namespace llvm {
+class AnalysisUsage;
+class Function;
+class LoopInfo;
+class TargetLibraryInfo;
+
+/// This is an alternative analysis pass to
+/// BranchProbabilityInfoWrapperPass.  The difference is that with this pass the
+/// branch probabilities are not computed when the analysis pass is executed but
+/// rather when the BPI results 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(LazyBPIPass)
+///
+/// 2. Similarly, getAnalysisUsage should call:
+///
+///   LazyBranchProbabilityInfoPass::getLazyBPIAnalysisUsage(AU)
+///
+/// 3. The computed BPI should be requested with
+///    getAnalysis<LazyBranchProbabilityInfoPass>().getBPI() before LoopInfo
+///    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 LazyBranchProbabilityInfoPass : public FunctionPass {
+
+  /// Wraps a BPI to allow lazy computation of the branch probabilities.
+  ///
+  /// A pass that only conditionally uses BPI can uncondtionally require the
+  /// analysis without paying for the overhead if BPI doesn't end up being used.
+  class LazyBranchProbabilityInfo {
+  public:
+    LazyBranchProbabilityInfo(const Function *F, const LoopInfo *LI,
+                              const TargetLibraryInfo *TLI)
+        : Calculated(false), F(F), LI(LI), TLI(TLI) {}
+
+    /// Retrieve the BPI with the branch probabilities computed.
+    BranchProbabilityInfo &getCalculated() {
+      if (!Calculated) {
+        assert(F && LI && "call setAnalysis");
+        BPI.calculate(*F, *LI, TLI);
+        Calculated = true;
+      }
+      return BPI;
+    }
+
+    const BranchProbabilityInfo &getCalculated() const {
+      return const_cast<LazyBranchProbabilityInfo *>(this)->getCalculated();
+    }
+
+  private:
+    BranchProbabilityInfo BPI;
+    bool Calculated;
+    const Function *F;
+    const LoopInfo *LI;
+    const TargetLibraryInfo *TLI;
+  };
+
+  std::unique_ptr<LazyBranchProbabilityInfo> LBPI;
+
+public:
+  static char ID;
+
+  LazyBranchProbabilityInfoPass();
+
+  /// Compute and return the branch probabilities.
+  BranchProbabilityInfo &getBPI() { return LBPI->getCalculated(); }
+
+  /// Compute and return the branch probabilities.
+  const BranchProbabilityInfo &getBPI() const { return LBPI->getCalculated(); }
+
+  void getAnalysisUsage(AnalysisUsage &AU) const override;
+
+  /// Helper for client passes to set up the analysis usage on behalf of this
+  /// pass.
+  static void getLazyBPIAnalysisUsage(AnalysisUsage &AU);
+
+  bool runOnFunction(Function &F) override;
+  void releaseMemory() override;
+  void print(raw_ostream &OS, const Module *M) const override;
+};
+
+/// Helper for client passes to initialize dependent passes for LBPI.
+void initializeLazyBPIPassPass(PassRegistry &Registry);
+
+/// Simple trait class that provides a mapping between BPI passes and the
+/// corresponding BPInfo.
+template <typename PassT> struct BPIPassTrait {
+  static PassT &getBPI(PassT *P) { return *P; }
+};
+
+template <> struct BPIPassTrait<LazyBranchProbabilityInfoPass> {
+  static BranchProbabilityInfo &getBPI(LazyBranchProbabilityInfoPass *P) {
+    return P->getBPI();
+  }
+};
+}
+#endif