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diff --git a/include/llvm/IR/OptBisect.h b/include/llvm/IR/OptBisect.h
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+++ b/include/llvm/IR/OptBisect.h
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+//===----------- llvm/IR/OptBisect.h - LLVM Bisect support -------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file declares the interface for bisecting optimizations.
+///
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_IR_OPTBISECT_H
+#define LLVM_IR_OPTBISECT_H
+
+namespace llvm {
+
+class Pass;
+class StringRef;
+class Twine;
+
+/// This class implements a mechanism to disable passes and individual
+/// optimizations at compile time based on a command line option
+/// (-opt-bisect-limit) in order to perform a bisecting search for
+/// optimization-related problems.
+class OptBisect {
+public:
+  /// \brief Default constructor, initializes the OptBisect state based on the
+  /// -opt-bisect-limit command line argument.
+  ///
+  /// By default, bisection is disabled.
+  ///
+  /// Clients should not instantiate this class directly.  All access should go
+  /// through LLVMContext.
+  OptBisect();
+
+  /// Checks the bisect limit to determine if the specified pass should run.
+  ///
+  /// This function will immediate return true if bisection is disabled. If the
+  /// bisect limit is set to -1, the function will print a message describing
+  /// the pass and the bisect number assigned to it and return true.  Otherwise,
+  /// the function will print a message with the bisect number assigned to the
+  /// pass and indicating whether or not the pass will be run and return true if
+  /// the bisect limit has not yet been exceded or false if it has.
+  ///
+  /// Most passes should not call this routine directly.  Instead, it is called
+  /// through a helper routine provided by the pass base class.  For instance,
+  /// function passes should call FunctionPass::skipFunction().
+  template <class UnitT>
+  bool shouldRunPass(const Pass *P, const UnitT &U);
+
+  /// Checks the bisect limit to determine if the optimization described by the
+  /// /p Desc argument should run.
+  ///
+  /// This function will immediate return true if bisection is disabled. If the
+  /// bisect limit is set to -1, the function will print a message with the
+  /// bisect number assigned to the optimization along with the /p Desc
+  /// description and return true.  Otherwise, the function will print a message
+  /// with the bisect number assigned to the optimization and indicating whether
+  /// or not the pass will be run and return true if the bisect limit has not
+  /// yet been exceded or false if it has.
+  ///
+  /// Passes may call this function to provide more fine grained control over
+  /// individual optimizations performed by the pass.  Passes which cannot be
+  /// skipped entirely (such as non-optional code generation passes) may still
+  /// call this function to control whether or not individual optional
+  /// transformations are performed.
+  bool shouldRunCase(const Twine &Desc);
+
+private:
+  bool checkPass(const StringRef PassName, const StringRef TargetDesc);
+
+  bool BisectEnabled = false;
+  unsigned LastBisectNum = 0;
+};
+
+} // end namespace llvm
+
+#endif // LLVM_IR_OPTBISECT_H