llvm/lib/CodeGen/CriticalAntiDepBreaker.h
Mehdi Amini f6071e14c5 [NFC] Header cleanup
Removed some unused headers, replaced some headers with forward class declarations.

Found using simple scripts like this one:
clear && ack --cpp -l '#include "llvm/ADT/IndexedMap.h"' | xargs grep -L 'IndexedMap[<]' | xargs grep -n --color=auto 'IndexedMap'

Patch by Eugene Kosov <claprix@yandex.ru>

Differential Revision: http://reviews.llvm.org/D19219

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@266595 91177308-0d34-0410-b5e6-96231b3b80d8
2016-04-18 09:17:29 +00:00

107 lines
4.1 KiB
C++

//=- llvm/CodeGen/CriticalAntiDepBreaker.h - Anti-Dep Support -*- C++ -*-=//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the CriticalAntiDepBreaker class, which
// implements register anti-dependence breaking along a blocks
// critical path during post-RA scheduler.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_CODEGEN_CRITICALANTIDEPBREAKER_H
#define LLVM_LIB_CODEGEN_CRITICALANTIDEPBREAKER_H
#include "AntiDepBreaker.h"
#include "llvm/ADT/BitVector.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/RegisterClassInfo.h"
#include "llvm/CodeGen/ScheduleDAG.h"
namespace llvm {
class RegisterClassInfo;
class TargetInstrInfo;
class TargetRegisterInfo;
class MachineFunction;
class LLVM_LIBRARY_VISIBILITY CriticalAntiDepBreaker : public AntiDepBreaker {
MachineFunction& MF;
MachineRegisterInfo &MRI;
const TargetInstrInfo *TII;
const TargetRegisterInfo *TRI;
const RegisterClassInfo &RegClassInfo;
/// The set of allocatable registers.
/// We'll be ignoring anti-dependencies on non-allocatable registers,
/// because they may not be safe to break.
const BitVector AllocatableSet;
/// For live regs that are only used in one register class in a
/// live range, the register class. If the register is not live, the
/// corresponding value is null. If the register is live but used in
/// multiple register classes, the corresponding value is -1 casted to a
/// pointer.
std::vector<const TargetRegisterClass*> Classes;
/// Map registers to all their references within a live range.
std::multimap<unsigned, MachineOperand *> RegRefs;
typedef std::multimap<unsigned, MachineOperand *>::const_iterator
RegRefIter;
/// The index of the most recent kill (proceeding bottom-up),
/// or ~0u if the register is not live.
std::vector<unsigned> KillIndices;
/// The index of the most recent complete def (proceeding
/// bottom up), or ~0u if the register is live.
std::vector<unsigned> DefIndices;
/// A set of registers which are live and cannot be changed to
/// break anti-dependencies.
BitVector KeepRegs;
public:
CriticalAntiDepBreaker(MachineFunction& MFi, const RegisterClassInfo&);
~CriticalAntiDepBreaker() override;
/// Initialize anti-dep breaking for a new basic block.
void StartBlock(MachineBasicBlock *BB) override;
/// Identifiy anti-dependencies along the critical path
/// of the ScheduleDAG and break them by renaming registers.
unsigned BreakAntiDependencies(const std::vector<SUnit>& SUnits,
MachineBasicBlock::iterator Begin,
MachineBasicBlock::iterator End,
unsigned InsertPosIndex,
DbgValueVector &DbgValues) override;
/// Update liveness information to account for the current
/// instruction, which will not be scheduled.
void Observe(MachineInstr &MI, unsigned Count,
unsigned InsertPosIndex) override;
/// Finish anti-dep breaking for a basic block.
void FinishBlock() override;
private:
void PrescanInstruction(MachineInstr &MI);
void ScanInstruction(MachineInstr &MI, unsigned Count);
bool isNewRegClobberedByRefs(RegRefIter RegRefBegin,
RegRefIter RegRefEnd,
unsigned NewReg);
unsigned findSuitableFreeRegister(RegRefIter RegRefBegin,
RegRefIter RegRefEnd,
unsigned AntiDepReg,
unsigned LastNewReg,
const TargetRegisterClass *RC,
SmallVectorImpl<unsigned> &Forbid);
};
}
#endif