llvm-6502/lib/Target/ARM/Thumb1InstrInfo.cpp
2010-05-22 01:47:14 +00:00

267 lines
9.0 KiB
C++

//===- Thumb1InstrInfo.cpp - Thumb-1 Instruction Information ----*- 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 the Thumb-1 implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "Thumb1InstrInfo.h"
#include "ARM.h"
#include "ARMGenInstrInfo.inc"
#include "ARMMachineFunctionInfo.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/MachineMemOperand.h"
#include "llvm/CodeGen/PseudoSourceValue.h"
#include "llvm/ADT/SmallVector.h"
#include "Thumb1InstrInfo.h"
using namespace llvm;
Thumb1InstrInfo::Thumb1InstrInfo(const ARMSubtarget &STI)
: ARMBaseInstrInfo(STI), RI(*this, STI) {
}
unsigned Thumb1InstrInfo::getUnindexedOpcode(unsigned Opc) const {
return 0;
}
bool Thumb1InstrInfo::copyRegToReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned DestReg, unsigned SrcReg,
const TargetRegisterClass *DestRC,
const TargetRegisterClass *SrcRC,
DebugLoc DL) const {
if (DestRC == ARM::GPRRegisterClass) {
if (SrcRC == ARM::GPRRegisterClass) {
BuildMI(MBB, I, DL, get(ARM::tMOVgpr2gpr), DestReg).addReg(SrcReg);
return true;
} else if (SrcRC == ARM::tGPRRegisterClass) {
BuildMI(MBB, I, DL, get(ARM::tMOVtgpr2gpr), DestReg).addReg(SrcReg);
return true;
}
} else if (DestRC == ARM::tGPRRegisterClass) {
if (SrcRC == ARM::GPRRegisterClass) {
BuildMI(MBB, I, DL, get(ARM::tMOVgpr2tgpr), DestReg).addReg(SrcReg);
return true;
} else if (SrcRC == ARM::tGPRRegisterClass) {
BuildMI(MBB, I, DL, get(ARM::tMOVr), DestReg).addReg(SrcReg);
return true;
}
}
return false;
}
bool Thumb1InstrInfo::
canFoldMemoryOperand(const MachineInstr *MI,
const SmallVectorImpl<unsigned> &Ops) const {
if (Ops.size() != 1) return false;
unsigned OpNum = Ops[0];
unsigned Opc = MI->getOpcode();
switch (Opc) {
default: break;
case ARM::tMOVr:
case ARM::tMOVtgpr2gpr:
case ARM::tMOVgpr2tgpr:
case ARM::tMOVgpr2gpr: {
if (OpNum == 0) { // move -> store
unsigned SrcReg = MI->getOperand(1).getReg();
if (TargetRegisterInfo::isPhysicalRegister(SrcReg) &&
!isARMLowRegister(SrcReg))
// tSpill cannot take a high register operand.
return false;
} else { // move -> load
unsigned DstReg = MI->getOperand(0).getReg();
if (TargetRegisterInfo::isPhysicalRegister(DstReg) &&
!isARMLowRegister(DstReg))
// tRestore cannot target a high register operand.
return false;
}
return true;
}
}
return false;
}
void Thumb1InstrInfo::
storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned SrcReg, bool isKill, int FI,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) const {
assert((RC == ARM::tGPRRegisterClass ||
(TargetRegisterInfo::isPhysicalRegister(SrcReg) &&
isARMLowRegister(SrcReg))) && "Unknown regclass!");
if (RC == ARM::tGPRRegisterClass ||
(TargetRegisterInfo::isPhysicalRegister(SrcReg) &&
isARMLowRegister(SrcReg))) {
DebugLoc DL;
if (I != MBB.end()) DL = I->getDebugLoc();
MachineFunction &MF = *MBB.getParent();
MachineFrameInfo &MFI = *MF.getFrameInfo();
MachineMemOperand *MMO =
MF.getMachineMemOperand(PseudoSourceValue::getFixedStack(FI),
MachineMemOperand::MOStore, 0,
MFI.getObjectSize(FI),
MFI.getObjectAlignment(FI));
AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::tSpill))
.addReg(SrcReg, getKillRegState(isKill))
.addFrameIndex(FI).addImm(0).addMemOperand(MMO));
}
}
void Thumb1InstrInfo::
loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned DestReg, int FI,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) const {
assert((RC == ARM::tGPRRegisterClass ||
(TargetRegisterInfo::isPhysicalRegister(DestReg) &&
isARMLowRegister(DestReg))) && "Unknown regclass!");
if (RC == ARM::tGPRRegisterClass ||
(TargetRegisterInfo::isPhysicalRegister(DestReg) &&
isARMLowRegister(DestReg))) {
DebugLoc DL;
if (I != MBB.end()) DL = I->getDebugLoc();
MachineFunction &MF = *MBB.getParent();
MachineFrameInfo &MFI = *MF.getFrameInfo();
MachineMemOperand *MMO =
MF.getMachineMemOperand(PseudoSourceValue::getFixedStack(FI),
MachineMemOperand::MOLoad, 0,
MFI.getObjectSize(FI),
MFI.getObjectAlignment(FI));
AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::tRestore), DestReg)
.addFrameIndex(FI).addImm(0).addMemOperand(MMO));
}
}
bool Thumb1InstrInfo::
spillCalleeSavedRegisters(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
const std::vector<CalleeSavedInfo> &CSI,
const TargetRegisterInfo *TRI) const {
if (CSI.empty())
return false;
DebugLoc DL;
if (MI != MBB.end()) DL = MI->getDebugLoc();
MachineInstrBuilder MIB = BuildMI(MBB, MI, DL, get(ARM::tPUSH));
AddDefaultPred(MIB);
for (unsigned i = CSI.size(); i != 0; --i) {
unsigned Reg = CSI[i-1].getReg();
bool isKill = true;
// Add the callee-saved register as live-in unless it's LR and
// @llvm.returnaddress is called. If LR is returned for @llvm.returnaddress
// then it's already added to the function and entry block live-in sets.
if (Reg == ARM::LR) {
MachineFunction &MF = *MBB.getParent();
if (MF.getFrameInfo()->isReturnAddressTaken() &&
MF.getRegInfo().isLiveIn(Reg))
isKill = false;
}
if (isKill) {
MBB.addLiveIn(Reg);
MIB.addReg(Reg, RegState::Kill);
}
}
return true;
}
bool Thumb1InstrInfo::
restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
const std::vector<CalleeSavedInfo> &CSI,
const TargetRegisterInfo *TRI) const {
MachineFunction &MF = *MBB.getParent();
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
if (CSI.empty())
return false;
bool isVarArg = AFI->getVarArgsRegSaveSize() > 0;
DebugLoc DL = MI->getDebugLoc();
MachineInstrBuilder MIB = BuildMI(MF, DL, get(ARM::tPOP));
AddDefaultPred(MIB);
bool NumRegs = false;
for (unsigned i = CSI.size(); i != 0; --i) {
unsigned Reg = CSI[i-1].getReg();
if (Reg == ARM::LR) {
// Special epilogue for vararg functions. See emitEpilogue
if (isVarArg)
continue;
Reg = ARM::PC;
(*MIB).setDesc(get(ARM::tPOP_RET));
MI = MBB.erase(MI);
}
MIB.addReg(Reg, getDefRegState(true));
NumRegs = true;
}
// It's illegal to emit pop instruction without operands.
if (NumRegs)
MBB.insert(MI, &*MIB);
else
MF.DeleteMachineInstr(MIB);
return true;
}
MachineInstr *Thumb1InstrInfo::
foldMemoryOperandImpl(MachineFunction &MF, MachineInstr *MI,
const SmallVectorImpl<unsigned> &Ops, int FI) const {
if (Ops.size() != 1) return NULL;
unsigned OpNum = Ops[0];
unsigned Opc = MI->getOpcode();
MachineInstr *NewMI = NULL;
switch (Opc) {
default: break;
case ARM::tMOVr:
case ARM::tMOVtgpr2gpr:
case ARM::tMOVgpr2tgpr:
case ARM::tMOVgpr2gpr: {
if (OpNum == 0) { // move -> store
unsigned SrcReg = MI->getOperand(1).getReg();
bool isKill = MI->getOperand(1).isKill();
if (TargetRegisterInfo::isPhysicalRegister(SrcReg) &&
!isARMLowRegister(SrcReg))
// tSpill cannot take a high register operand.
break;
NewMI = AddDefaultPred(BuildMI(MF, MI->getDebugLoc(), get(ARM::tSpill))
.addReg(SrcReg, getKillRegState(isKill))
.addFrameIndex(FI).addImm(0));
} else { // move -> load
unsigned DstReg = MI->getOperand(0).getReg();
if (TargetRegisterInfo::isPhysicalRegister(DstReg) &&
!isARMLowRegister(DstReg))
// tRestore cannot target a high register operand.
break;
bool isDead = MI->getOperand(0).isDead();
NewMI = AddDefaultPred(BuildMI(MF, MI->getDebugLoc(), get(ARM::tRestore))
.addReg(DstReg,
RegState::Define | getDeadRegState(isDead))
.addFrameIndex(FI).addImm(0));
}
break;
}
}
return NewMI;
}