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//===-- Thumb1InstrInfo.cpp - Thumb-1 Instruction Information -------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains the Thumb-1 implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "Thumb1InstrInfo.h"
#include "ARMSubtarget.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineMemOperand.h"
#include "llvm/MC/MCInst.h"
using namespace llvm;
Thumb1InstrInfo::Thumb1InstrInfo(const ARMSubtarget &STI)
: ARMBaseInstrInfo(STI), RI() {}
/// Return the noop instruction to use for a noop.
void Thumb1InstrInfo::getNoop(MCInst &NopInst) const {
NopInst.setOpcode(ARM::tMOVr);
NopInst.addOperand(MCOperand::createReg(ARM::R8));
NopInst.addOperand(MCOperand::createReg(ARM::R8));
NopInst.addOperand(MCOperand::createImm(ARMCC::AL));
NopInst.addOperand(MCOperand::createReg(0));
}
unsigned Thumb1InstrInfo::getUnindexedOpcode(unsigned Opc) const {
return 0;
}
void Thumb1InstrInfo::copyPhysReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
const DebugLoc &DL, MCRegister DestReg,
MCRegister SrcReg, bool KillSrc) const {
// Need to check the arch.
MachineFunction &MF = *MBB.getParent();
const ARMSubtarget &st = MF.getSubtarget<ARMSubtarget>();
assert(ARM::GPRRegClass.contains(DestReg, SrcReg) &&
"Thumb1 can only copy GPR registers");
if (st.hasV6Ops() || ARM::hGPRRegClass.contains(SrcReg)
|| !ARM::tGPRRegClass.contains(DestReg))
BuildMI(MBB, I, DL, get(ARM::tMOVr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc))
.add(predOps(ARMCC::AL));
else {
// FIXME: Can also use 'mov hi, $src; mov $dst, hi',
// with hi as either r10 or r11.
const TargetRegisterInfo *RegInfo = st.getRegisterInfo();
if (MBB.computeRegisterLiveness(RegInfo, ARM::CPSR, I)
== MachineBasicBlock::LQR_Dead) {
BuildMI(MBB, I, DL, get(ARM::tMOVSr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc))
->addRegisterDead(ARM::CPSR, RegInfo);
return;
}
// 'MOV lo, lo' is unpredictable on < v6, so use the stack to do it
BuildMI(MBB, I, DL, get(ARM::tPUSH))
.add(predOps(ARMCC::AL))
.addReg(SrcReg, getKillRegState(KillSrc));
BuildMI(MBB, I, DL, get(ARM::tPOP))
.add(predOps(ARMCC::AL))
.addReg(DestReg, getDefRegState(true));
}
}
void Thumb1InstrInfo::
storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned SrcReg, bool isKill, int FI,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) const {
assert((RC == &ARM::tGPRRegClass ||
(Register::isPhysicalRegister(SrcReg) && isARMLowRegister(SrcReg))) &&
"Unknown regclass!");
if (RC == &ARM::tGPRRegClass ||
(Register::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(
MachinePointerInfo::getFixedStack(MF, FI), MachineMemOperand::MOStore,
MFI.getObjectSize(FI), MFI.getObjectAlignment(FI));
BuildMI(MBB, I, DL, get(ARM::tSTRspi))
.addReg(SrcReg, getKillRegState(isKill))
.addFrameIndex(FI)
.addImm(0)
.addMemOperand(MMO)
.add(predOps(ARMCC::AL));
}
}
void Thumb1InstrInfo::
loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
unsigned DestReg, int FI,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) const {
assert(
(RC->hasSuperClassEq(&ARM::tGPRRegClass) ||
(Register::isPhysicalRegister(DestReg) && isARMLowRegister(DestReg))) &&
"Unknown regclass!");
if (RC->hasSuperClassEq(&ARM::tGPRRegClass) ||
(Register::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(
MachinePointerInfo::getFixedStack(MF, FI), MachineMemOperand::MOLoad,
MFI.getObjectSize(FI), MFI.getObjectAlignment(FI));
BuildMI(MBB, I, DL, get(ARM::tLDRspi), DestReg)
.addFrameIndex(FI)
.addImm(0)
.addMemOperand(MMO)
.add(predOps(ARMCC::AL));
}
}
void Thumb1InstrInfo::expandLoadStackGuard(
MachineBasicBlock::iterator MI) const {
MachineFunction &MF = *MI->getParent()->getParent();
const TargetMachine &TM = MF.getTarget();
if (TM.isPositionIndependent())
expandLoadStackGuardBase(MI, ARM::tLDRLIT_ga_pcrel, ARM::tLDRi);
else
expandLoadStackGuardBase(MI, ARM::tLDRLIT_ga_abs, ARM::tLDRi);
}
bool Thumb1InstrInfo::canCopyGluedNodeDuringSchedule(SDNode *N) const {
// In Thumb1 the scheduler may need to schedule a cross-copy between GPRS and CPSR
// but this is not always possible there, so allow the Scheduler to clone tADCS and tSBCS
// even if they have glue.
// FIXME. Actually implement the cross-copy where it is possible (post v6)
// because these copies entail more spilling.
unsigned Opcode = N->getMachineOpcode();
if (Opcode == ARM::tADCS || Opcode == ARM::tSBCS)
return true;
return false;
}