llvm-6502/lib/Target/ARM/ThumbInstrInfo.cpp
Anton Korobeynikov 55ad1f22b4 Simplify a bit
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74385 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-27 12:59:03 +00:00

313 lines
9.9 KiB
C++

//===- ThumbInstrInfo.cpp - Thumb 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 implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "ARMInstrInfo.h"
#include "ARM.h"
#include "ARMGenInstrInfo.inc"
#include "ARMMachineFunctionInfo.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/ADT/SmallVector.h"
#include "ThumbInstrInfo.h"
using namespace llvm;
ThumbInstrInfo::ThumbInstrInfo(const ARMSubtarget &STI)
: ARMBaseInstrInfo(STI), RI(*this, STI) {
}
bool ThumbInstrInfo::isMoveInstr(const MachineInstr &MI,
unsigned &SrcReg, unsigned &DstReg,
unsigned& SrcSubIdx, unsigned& DstSubIdx) const {
SrcSubIdx = DstSubIdx = 0; // No sub-registers.
unsigned oc = MI.getOpcode();
switch (oc) {
default:
return false;
// FIXME: Thumb2
case ARM::tMOVr:
case ARM::tMOVhir2lor:
case ARM::tMOVlor2hir:
case ARM::tMOVhir2hir:
assert(MI.getDesc().getNumOperands() >= 2 &&
MI.getOperand(0).isReg() &&
MI.getOperand(1).isReg() &&
"Invalid Thumb MOV instruction");
SrcReg = MI.getOperand(1).getReg();
DstReg = MI.getOperand(0).getReg();
return true;
}
}
unsigned ThumbInstrInfo::isLoadFromStackSlot(const MachineInstr *MI,
int &FrameIndex) const {
switch (MI->getOpcode()) {
default: break;
// FIXME: Thumb2
case ARM::tRestore:
if (MI->getOperand(1).isFI() &&
MI->getOperand(2).isImm() &&
MI->getOperand(2).getImm() == 0) {
FrameIndex = MI->getOperand(1).getIndex();
return MI->getOperand(0).getReg();
}
break;
}
return 0;
}
unsigned ThumbInstrInfo::isStoreToStackSlot(const MachineInstr *MI,
int &FrameIndex) const {
switch (MI->getOpcode()) {
default: break;
// FIXME: Thumb2
case ARM::tSpill:
if (MI->getOperand(1).isFI() &&
MI->getOperand(2).isImm() &&
MI->getOperand(2).getImm() == 0) {
FrameIndex = MI->getOperand(1).getIndex();
return MI->getOperand(0).getReg();
}
break;
}
return 0;
}
bool ThumbInstrInfo::copyRegToReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned DestReg, unsigned SrcReg,
const TargetRegisterClass *DestRC,
const TargetRegisterClass *SrcRC) const {
DebugLoc DL = DebugLoc::getUnknownLoc();
if (I != MBB.end()) DL = I->getDebugLoc();
// FIXME: Thumb2
if (DestRC == ARM::GPRRegisterClass) {
if (SrcRC == ARM::GPRRegisterClass) {
BuildMI(MBB, I, DL, get(ARM::tMOVhir2hir), DestReg).addReg(SrcReg);
return true;
} else if (SrcRC == ARM::tGPRRegisterClass) {
BuildMI(MBB, I, DL, get(ARM::tMOVlor2hir), DestReg).addReg(SrcReg);
return true;
}
} else if (DestRC == ARM::tGPRRegisterClass) {
if (SrcRC == ARM::GPRRegisterClass) {
BuildMI(MBB, I, DL, get(ARM::tMOVhir2lor), 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 ThumbInstrInfo::
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::tMOVlor2hir:
case ARM::tMOVhir2lor:
case ARM::tMOVhir2hir: {
if (OpNum == 0) { // move -> store
unsigned SrcReg = MI->getOperand(1).getReg();
if (RI.isPhysicalRegister(SrcReg) && !isARMLowRegister(SrcReg))
// tSpill cannot take a high register operand.
return false;
} else { // move -> load
unsigned DstReg = MI->getOperand(0).getReg();
if (RI.isPhysicalRegister(DstReg) && !isARMLowRegister(DstReg))
// tRestore cannot target a high register operand.
return false;
}
return true;
}
}
return false;
}
void ThumbInstrInfo::
storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned SrcReg, bool isKill, int FI,
const TargetRegisterClass *RC) const {
DebugLoc DL = DebugLoc::getUnknownLoc();
if (I != MBB.end()) DL = I->getDebugLoc();
assert(RC == ARM::tGPRRegisterClass && "Unknown regclass!");
// FIXME: Thumb2
if (RC == ARM::tGPRRegisterClass) {
BuildMI(MBB, I, DL, get(ARM::tSpill))
.addReg(SrcReg, getKillRegState(isKill))
.addFrameIndex(FI).addImm(0);
}
}
void ThumbInstrInfo::storeRegToAddr(MachineFunction &MF, unsigned SrcReg,
bool isKill,
SmallVectorImpl<MachineOperand> &Addr,
const TargetRegisterClass *RC,
SmallVectorImpl<MachineInstr*> &NewMIs) const{
DebugLoc DL = DebugLoc::getUnknownLoc();
unsigned Opc = 0;
// FIXME: Thumb2. Is GPRRegClass here correct?
assert(RC == ARM::GPRRegisterClass && "Unknown regclass!");
if (RC == ARM::GPRRegisterClass) {
Opc = Addr[0].isFI() ? ARM::tSpill : ARM::tSTR;
}
MachineInstrBuilder MIB =
BuildMI(MF, DL, get(Opc)).addReg(SrcReg, getKillRegState(isKill));
for (unsigned i = 0, e = Addr.size(); i != e; ++i)
MIB.addOperand(Addr[i]);
NewMIs.push_back(MIB);
return;
}
void ThumbInstrInfo::
loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned DestReg, int FI,
const TargetRegisterClass *RC) const {
DebugLoc DL = DebugLoc::getUnknownLoc();
if (I != MBB.end()) DL = I->getDebugLoc();
// FIXME: Thumb2
assert(RC == ARM::tGPRRegisterClass && "Unknown regclass!");
if (RC == ARM::tGPRRegisterClass) {
BuildMI(MBB, I, DL, get(ARM::tRestore), DestReg)
.addFrameIndex(FI).addImm(0);
}
}
void ThumbInstrInfo::
loadRegFromAddr(MachineFunction &MF, unsigned DestReg,
SmallVectorImpl<MachineOperand> &Addr,
const TargetRegisterClass *RC,
SmallVectorImpl<MachineInstr*> &NewMIs) const {
DebugLoc DL = DebugLoc::getUnknownLoc();
unsigned Opc = 0;
// FIXME: Thumb2. Is GPRRegClass ok here?
if (RC == ARM::GPRRegisterClass) {
Opc = Addr[0].isFI() ? ARM::tRestore : ARM::tLDR;
}
MachineInstrBuilder MIB = BuildMI(MF, DL, get(Opc), DestReg);
for (unsigned i = 0, e = Addr.size(); i != e; ++i)
MIB.addOperand(Addr[i]);
NewMIs.push_back(MIB);
return;
}
bool ThumbInstrInfo::
spillCalleeSavedRegisters(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
const std::vector<CalleeSavedInfo> &CSI) const {
if (CSI.empty())
return false;
DebugLoc DL = DebugLoc::getUnknownLoc();
if (MI != MBB.end()) DL = MI->getDebugLoc();
MachineInstrBuilder MIB = BuildMI(MBB, MI, DL, get(ARM::tPUSH));
for (unsigned i = CSI.size(); i != 0; --i) {
unsigned Reg = CSI[i-1].getReg();
// Add the callee-saved register as live-in. It's killed at the spill.
MBB.addLiveIn(Reg);
MIB.addReg(Reg, RegState::Kill);
}
return true;
}
bool ThumbInstrInfo::
restoreCalleeSavedRegisters(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
const std::vector<CalleeSavedInfo> &CSI) const {
MachineFunction &MF = *MBB.getParent();
ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
if (CSI.empty())
return false;
bool isVarArg = AFI->getVarArgsRegSaveSize() > 0;
MachineInstr *PopMI = MF.CreateMachineInstr(get(ARM::tPOP),MI->getDebugLoc());
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;
PopMI->setDesc(get(ARM::tPOP_RET));
MI = MBB.erase(MI);
}
PopMI->addOperand(MachineOperand::CreateReg(Reg, true));
}
// It's illegal to emit pop instruction without operands.
if (PopMI->getNumOperands() > 0)
MBB.insert(MI, PopMI);
return true;
}
MachineInstr *ThumbInstrInfo::
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::tMOVlor2hir:
case ARM::tMOVhir2lor:
case ARM::tMOVhir2hir: {
if (OpNum == 0) { // move -> store
unsigned SrcReg = MI->getOperand(1).getReg();
bool isKill = MI->getOperand(1).isKill();
if (RI.isPhysicalRegister(SrcReg) && !isARMLowRegister(SrcReg))
// tSpill cannot take a high register operand.
break;
NewMI = 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 (RI.isPhysicalRegister(DstReg) && !isARMLowRegister(DstReg))
// tRestore cannot target a high register operand.
break;
bool isDead = MI->getOperand(0).isDead();
NewMI = BuildMI(MF, MI->getDebugLoc(), get(ARM::tRestore))
.addReg(DstReg, RegState::Define | getDeadRegState(isDead))
.addFrameIndex(FI).addImm(0);
}
break;
}
}
return NewMI;
}