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//===- llvm/Transforms/Utils/BypassSlowDivision.h --------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains an optimization for div and rem on architectures that
// execute short instructions significantly faster than longer instructions.
// For example, on Intel Atom 32-bit divides are slow enough that during
// runtime it is profitable to check the value of the operands, and if they are
// positive and less than 256 use an unsigned 8-bit divide.
//
//===----------------------------------------------------------------------===//
#ifndef TRANSFORMS_UTILS_BYPASSSLOWDIVISION_H
#define TRANSFORMS_UTILS_BYPASSSLOWDIVISION_H
#include "llvm/Function.h"
/// This optimization identifies DIV instructions that can be
/// profitably bypassed and carried out with a shorter, faster divide.
bool bypassSlowDivision(llvm::Function &F,
llvm::Function::iterator &I,
const llvm::DenseMap<llvm::Type *, llvm::Type *> &BypassTypeMap);
#endif
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