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//===- llvm/IR/OptBisect.h - LLVM Bisect support ----------------*- C++ -*-===//
// 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.
#include "llvm/ADT/StringRef.h"
namespace llvm {
class Pass;
/// 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 {
/// \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.
/// 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);
bool checkPass(const StringRef PassName, const StringRef TargetDesc);
bool BisectEnabled = false;
unsigned LastBisectNum = 0;
} // end namespace llvm