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//=- llvm/CodeGen/AntiDepBreaker.h - Anti-Dependence Breaking -*- C++ -*-=//
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// The LLVM Compiler Infrastructure
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//===----------------------------------------------------------------------===//
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// This file implements the AntiDepBreaker class, which implements
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// anti-dependence breaking heuristics for post-register-allocation scheduling.
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_CODEGEN_ANTIDEPBREAKER_H
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#define LLVM_CODEGEN_ANTIDEPBREAKER_H
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#include "llvm/CodeGen/MachineBasicBlock.h"
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#include "llvm/CodeGen/MachineFrameInfo.h"
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#include "llvm/CodeGen/MachineFunction.h"
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#include "llvm/CodeGen/MachineRegisterInfo.h"
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#include "llvm/CodeGen/ScheduleDAG.h"
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#include "llvm/Target/TargetRegisterInfo.h"
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/// AntiDepBreaker - This class works into conjunction with the
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/// post-RA scheduler to rename registers to break register
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/// anti-dependencies.
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class AntiDepBreaker {
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virtual ~AntiDepBreaker();
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/// Start - Initialize anti-dep breaking for a new basic block.
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virtual void StartBlock(MachineBasicBlock *BB) =0;
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/// BreakAntiDependencies - Identifiy anti-dependencies within a
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/// basic-block region and break them by renaming registers. Return
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/// the number of anti-dependencies broken.
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virtual unsigned BreakAntiDependencies(std::vector<SUnit>& SUnits,
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MachineBasicBlock::iterator& Begin,
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MachineBasicBlock::iterator& End,
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unsigned InsertPosIndex) =0;
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/// Observe - Update liveness information to account for the current
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/// instruction, which will not be scheduled.
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virtual void Observe(MachineInstr *MI, unsigned Count,
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unsigned InsertPosIndex) =0;
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/// Finish - Finish anti-dep breaking for a basic block.
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virtual void FinishBlock() =0;