llvm-6502/lib/Target/PowerPC/PPCInstrInfo.cpp
2008-02-13 02:46:49 +00:00

647 lines
24 KiB
C++

//===- PPCInstrInfo.cpp - PowerPC32 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 PowerPC implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "PPCInstrInfo.h"
#include "PPCInstrBuilder.h"
#include "PPCPredicates.h"
#include "PPCGenInstrInfo.inc"
#include "PPCTargetMachine.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
using namespace llvm;
PPCInstrInfo::PPCInstrInfo(PPCTargetMachine &tm)
: TargetInstrInfoImpl(PPCInsts, array_lengthof(PPCInsts)), TM(tm),
RI(*TM.getSubtargetImpl(), *this) {}
/// getPointerRegClass - Return the register class to use to hold pointers.
/// This is used for addressing modes.
const TargetRegisterClass *PPCInstrInfo::getPointerRegClass() const {
if (TM.getSubtargetImpl()->isPPC64())
return &PPC::G8RCRegClass;
else
return &PPC::GPRCRegClass;
}
bool PPCInstrInfo::isMoveInstr(const MachineInstr& MI,
unsigned& sourceReg,
unsigned& destReg) const {
unsigned oc = MI.getOpcode();
if (oc == PPC::OR || oc == PPC::OR8 || oc == PPC::VOR ||
oc == PPC::OR4To8 || oc == PPC::OR8To4) { // or r1, r2, r2
assert(MI.getNumOperands() >= 3 &&
MI.getOperand(0).isRegister() &&
MI.getOperand(1).isRegister() &&
MI.getOperand(2).isRegister() &&
"invalid PPC OR instruction!");
if (MI.getOperand(1).getReg() == MI.getOperand(2).getReg()) {
sourceReg = MI.getOperand(1).getReg();
destReg = MI.getOperand(0).getReg();
return true;
}
} else if (oc == PPC::ADDI) { // addi r1, r2, 0
assert(MI.getNumOperands() >= 3 &&
MI.getOperand(0).isRegister() &&
MI.getOperand(2).isImmediate() &&
"invalid PPC ADDI instruction!");
if (MI.getOperand(1).isRegister() && MI.getOperand(2).getImm() == 0) {
sourceReg = MI.getOperand(1).getReg();
destReg = MI.getOperand(0).getReg();
return true;
}
} else if (oc == PPC::ORI) { // ori r1, r2, 0
assert(MI.getNumOperands() >= 3 &&
MI.getOperand(0).isRegister() &&
MI.getOperand(1).isRegister() &&
MI.getOperand(2).isImmediate() &&
"invalid PPC ORI instruction!");
if (MI.getOperand(2).getImm() == 0) {
sourceReg = MI.getOperand(1).getReg();
destReg = MI.getOperand(0).getReg();
return true;
}
} else if (oc == PPC::FMRS || oc == PPC::FMRD ||
oc == PPC::FMRSD) { // fmr r1, r2
assert(MI.getNumOperands() >= 2 &&
MI.getOperand(0).isRegister() &&
MI.getOperand(1).isRegister() &&
"invalid PPC FMR instruction");
sourceReg = MI.getOperand(1).getReg();
destReg = MI.getOperand(0).getReg();
return true;
} else if (oc == PPC::MCRF) { // mcrf cr1, cr2
assert(MI.getNumOperands() >= 2 &&
MI.getOperand(0).isRegister() &&
MI.getOperand(1).isRegister() &&
"invalid PPC MCRF instruction");
sourceReg = MI.getOperand(1).getReg();
destReg = MI.getOperand(0).getReg();
return true;
}
return false;
}
unsigned PPCInstrInfo::isLoadFromStackSlot(MachineInstr *MI,
int &FrameIndex) const {
switch (MI->getOpcode()) {
default: break;
case PPC::LD:
case PPC::LWZ:
case PPC::LFS:
case PPC::LFD:
if (MI->getOperand(1).isImm() && !MI->getOperand(1).getImm() &&
MI->getOperand(2).isFI()) {
FrameIndex = MI->getOperand(2).getIndex();
return MI->getOperand(0).getReg();
}
break;
}
return 0;
}
unsigned PPCInstrInfo::isStoreToStackSlot(MachineInstr *MI,
int &FrameIndex) const {
switch (MI->getOpcode()) {
default: break;
case PPC::STD:
case PPC::STW:
case PPC::STFS:
case PPC::STFD:
if (MI->getOperand(1).isImm() && !MI->getOperand(1).getImm() &&
MI->getOperand(2).isFI()) {
FrameIndex = MI->getOperand(2).getIndex();
return MI->getOperand(0).getReg();
}
break;
}
return 0;
}
// commuteInstruction - We can commute rlwimi instructions, but only if the
// rotate amt is zero. We also have to munge the immediates a bit.
MachineInstr *PPCInstrInfo::commuteInstruction(MachineInstr *MI) const {
// Normal instructions can be commuted the obvious way.
if (MI->getOpcode() != PPC::RLWIMI)
return TargetInstrInfoImpl::commuteInstruction(MI);
// Cannot commute if it has a non-zero rotate count.
if (MI->getOperand(3).getImm() != 0)
return 0;
// If we have a zero rotate count, we have:
// M = mask(MB,ME)
// Op0 = (Op1 & ~M) | (Op2 & M)
// Change this to:
// M = mask((ME+1)&31, (MB-1)&31)
// Op0 = (Op2 & ~M) | (Op1 & M)
// Swap op1/op2
unsigned Reg0 = MI->getOperand(0).getReg();
unsigned Reg1 = MI->getOperand(1).getReg();
unsigned Reg2 = MI->getOperand(2).getReg();
bool Reg1IsKill = MI->getOperand(1).isKill();
bool Reg2IsKill = MI->getOperand(2).isKill();
// If machine instrs are no longer in two-address forms, update
// destination register as well.
if (Reg0 == Reg1) {
// Must be two address instruction!
assert(MI->getDesc().getOperandConstraint(0, TOI::TIED_TO) &&
"Expecting a two-address instruction!");
MI->getOperand(0).setReg(Reg2);
Reg2IsKill = false;
}
MI->getOperand(2).setReg(Reg1);
MI->getOperand(1).setReg(Reg2);
MI->getOperand(2).setIsKill(Reg1IsKill);
MI->getOperand(1).setIsKill(Reg2IsKill);
// Swap the mask around.
unsigned MB = MI->getOperand(4).getImm();
unsigned ME = MI->getOperand(5).getImm();
MI->getOperand(4).setImm((ME+1) & 31);
MI->getOperand(5).setImm((MB-1) & 31);
return MI;
}
void PPCInstrInfo::insertNoop(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI) const {
BuildMI(MBB, MI, get(PPC::NOP));
}
// Branch analysis.
bool PPCInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB,MachineBasicBlock *&TBB,
MachineBasicBlock *&FBB,
std::vector<MachineOperand> &Cond) const {
// If the block has no terminators, it just falls into the block after it.
MachineBasicBlock::iterator I = MBB.end();
if (I == MBB.begin() || !isUnpredicatedTerminator(--I))
return false;
// Get the last instruction in the block.
MachineInstr *LastInst = I;
// If there is only one terminator instruction, process it.
if (I == MBB.begin() || !isUnpredicatedTerminator(--I)) {
if (LastInst->getOpcode() == PPC::B) {
TBB = LastInst->getOperand(0).getMBB();
return false;
} else if (LastInst->getOpcode() == PPC::BCC) {
// Block ends with fall-through condbranch.
TBB = LastInst->getOperand(2).getMBB();
Cond.push_back(LastInst->getOperand(0));
Cond.push_back(LastInst->getOperand(1));
return false;
}
// Otherwise, don't know what this is.
return true;
}
// Get the instruction before it if it's a terminator.
MachineInstr *SecondLastInst = I;
// If there are three terminators, we don't know what sort of block this is.
if (SecondLastInst && I != MBB.begin() &&
isUnpredicatedTerminator(--I))
return true;
// If the block ends with PPC::B and PPC:BCC, handle it.
if (SecondLastInst->getOpcode() == PPC::BCC &&
LastInst->getOpcode() == PPC::B) {
TBB = SecondLastInst->getOperand(2).getMBB();
Cond.push_back(SecondLastInst->getOperand(0));
Cond.push_back(SecondLastInst->getOperand(1));
FBB = LastInst->getOperand(0).getMBB();
return false;
}
// If the block ends with two PPC:Bs, handle it. The second one is not
// executed, so remove it.
if (SecondLastInst->getOpcode() == PPC::B &&
LastInst->getOpcode() == PPC::B) {
TBB = SecondLastInst->getOperand(0).getMBB();
I = LastInst;
I->eraseFromParent();
return false;
}
// Otherwise, can't handle this.
return true;
}
unsigned PPCInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const {
MachineBasicBlock::iterator I = MBB.end();
if (I == MBB.begin()) return 0;
--I;
if (I->getOpcode() != PPC::B && I->getOpcode() != PPC::BCC)
return 0;
// Remove the branch.
I->eraseFromParent();
I = MBB.end();
if (I == MBB.begin()) return 1;
--I;
if (I->getOpcode() != PPC::BCC)
return 1;
// Remove the branch.
I->eraseFromParent();
return 2;
}
unsigned
PPCInstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
MachineBasicBlock *FBB,
const std::vector<MachineOperand> &Cond) const {
// Shouldn't be a fall through.
assert(TBB && "InsertBranch must not be told to insert a fallthrough");
assert((Cond.size() == 2 || Cond.size() == 0) &&
"PPC branch conditions have two components!");
// One-way branch.
if (FBB == 0) {
if (Cond.empty()) // Unconditional branch
BuildMI(&MBB, get(PPC::B)).addMBB(TBB);
else // Conditional branch
BuildMI(&MBB, get(PPC::BCC))
.addImm(Cond[0].getImm()).addReg(Cond[1].getReg()).addMBB(TBB);
return 1;
}
// Two-way Conditional Branch.
BuildMI(&MBB, get(PPC::BCC))
.addImm(Cond[0].getImm()).addReg(Cond[1].getReg()).addMBB(TBB);
BuildMI(&MBB, get(PPC::B)).addMBB(FBB);
return 2;
}
void PPCInstrInfo::copyRegToReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned DestReg, unsigned SrcReg,
const TargetRegisterClass *DestRC,
const TargetRegisterClass *SrcRC) const {
if (DestRC != SrcRC) {
cerr << "Not yet supported!";
abort();
}
if (DestRC == PPC::GPRCRegisterClass) {
BuildMI(MBB, MI, get(PPC::OR), DestReg).addReg(SrcReg).addReg(SrcReg);
} else if (DestRC == PPC::G8RCRegisterClass) {
BuildMI(MBB, MI, get(PPC::OR8), DestReg).addReg(SrcReg).addReg(SrcReg);
} else if (DestRC == PPC::F4RCRegisterClass) {
BuildMI(MBB, MI, get(PPC::FMRS), DestReg).addReg(SrcReg);
} else if (DestRC == PPC::F8RCRegisterClass) {
BuildMI(MBB, MI, get(PPC::FMRD), DestReg).addReg(SrcReg);
} else if (DestRC == PPC::CRRCRegisterClass) {
BuildMI(MBB, MI, get(PPC::MCRF), DestReg).addReg(SrcReg);
} else if (DestRC == PPC::VRRCRegisterClass) {
BuildMI(MBB, MI, get(PPC::VOR), DestReg).addReg(SrcReg).addReg(SrcReg);
} else {
cerr << "Attempt to copy register that is not GPR or FPR";
abort();
}
}
static void StoreRegToStackSlot(const TargetInstrInfo &TII,
unsigned SrcReg, bool isKill, int FrameIdx,
const TargetRegisterClass *RC,
SmallVectorImpl<MachineInstr*> &NewMIs) {
if (RC == PPC::GPRCRegisterClass) {
if (SrcReg != PPC::LR) {
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::STW))
.addReg(SrcReg, false, false, isKill), FrameIdx));
} else {
// FIXME: this spills LR immediately to memory in one step. To do this,
// we use R11, which we know cannot be used in the prolog/epilog. This is
// a hack.
NewMIs.push_back(BuildMI(TII.get(PPC::MFLR), PPC::R11));
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::STW))
.addReg(PPC::R11, false, false, isKill), FrameIdx));
}
} else if (RC == PPC::G8RCRegisterClass) {
if (SrcReg != PPC::LR8) {
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::STD))
.addReg(SrcReg, false, false, isKill), FrameIdx));
} else {
// FIXME: this spills LR immediately to memory in one step. To do this,
// we use R11, which we know cannot be used in the prolog/epilog. This is
// a hack.
NewMIs.push_back(BuildMI(TII.get(PPC::MFLR8), PPC::X11));
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::STD))
.addReg(PPC::X11, false, false, isKill), FrameIdx));
}
} else if (RC == PPC::F8RCRegisterClass) {
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::STFD))
.addReg(SrcReg, false, false, isKill), FrameIdx));
} else if (RC == PPC::F4RCRegisterClass) {
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::STFS))
.addReg(SrcReg, false, false, isKill), FrameIdx));
} else if (RC == PPC::CRRCRegisterClass) {
// FIXME: We use R0 here, because it isn't available for RA.
// We need to store the CR in the low 4-bits of the saved value. First,
// issue a MFCR to save all of the CRBits.
NewMIs.push_back(BuildMI(TII.get(PPC::MFCR), PPC::R0));
// If the saved register wasn't CR0, shift the bits left so that they are in
// CR0's slot.
if (SrcReg != PPC::CR0) {
unsigned ShiftBits = PPCRegisterInfo::getRegisterNumbering(SrcReg)*4;
// rlwinm r0, r0, ShiftBits, 0, 31.
NewMIs.push_back(BuildMI(TII.get(PPC::RLWINM), PPC::R0)
.addReg(PPC::R0).addImm(ShiftBits).addImm(0).addImm(31));
}
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::STW))
.addReg(PPC::R0, false, false, isKill), FrameIdx));
} else if (RC == PPC::VRRCRegisterClass) {
// We don't have indexed addressing for vector loads. Emit:
// R0 = ADDI FI#
// STVX VAL, 0, R0
//
// FIXME: We use R0 here, because it isn't available for RA.
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::ADDI), PPC::R0),
FrameIdx, 0, 0));
NewMIs.push_back(BuildMI(TII.get(PPC::STVX))
.addReg(SrcReg, false, false, isKill).addReg(PPC::R0).addReg(PPC::R0));
} else {
assert(0 && "Unknown regclass!");
abort();
}
}
void
PPCInstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned SrcReg, bool isKill, int FrameIdx,
const TargetRegisterClass *RC) const {
SmallVector<MachineInstr*, 4> NewMIs;
StoreRegToStackSlot(*this, SrcReg, isKill, FrameIdx, RC, NewMIs);
for (unsigned i = 0, e = NewMIs.size(); i != e; ++i)
MBB.insert(MI, NewMIs[i]);
}
void PPCInstrInfo::storeRegToAddr(MachineFunction &MF, unsigned SrcReg,
bool isKill,
SmallVectorImpl<MachineOperand> &Addr,
const TargetRegisterClass *RC,
SmallVectorImpl<MachineInstr*> &NewMIs) const {
if (Addr[0].isFrameIndex()) {
StoreRegToStackSlot(*this, SrcReg, isKill, Addr[0].getIndex(), RC, NewMIs);
return;
}
unsigned Opc = 0;
if (RC == PPC::GPRCRegisterClass) {
Opc = PPC::STW;
} else if (RC == PPC::G8RCRegisterClass) {
Opc = PPC::STD;
} else if (RC == PPC::F8RCRegisterClass) {
Opc = PPC::STFD;
} else if (RC == PPC::F4RCRegisterClass) {
Opc = PPC::STFS;
} else if (RC == PPC::VRRCRegisterClass) {
Opc = PPC::STVX;
} else {
assert(0 && "Unknown regclass!");
abort();
}
MachineInstrBuilder MIB = BuildMI(get(Opc))
.addReg(SrcReg, false, false, isKill);
for (unsigned i = 0, e = Addr.size(); i != e; ++i) {
MachineOperand &MO = Addr[i];
if (MO.isRegister())
MIB.addReg(MO.getReg());
else if (MO.isImmediate())
MIB.addImm(MO.getImm());
else
MIB.addFrameIndex(MO.getIndex());
}
NewMIs.push_back(MIB);
return;
}
static void LoadRegFromStackSlot(const TargetInstrInfo &TII,
unsigned DestReg, int FrameIdx,
const TargetRegisterClass *RC,
SmallVectorImpl<MachineInstr*> &NewMIs) {
if (RC == PPC::GPRCRegisterClass) {
if (DestReg != PPC::LR) {
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::LWZ), DestReg),
FrameIdx));
} else {
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::LWZ), PPC::R11),
FrameIdx));
NewMIs.push_back(BuildMI(TII.get(PPC::MTLR)).addReg(PPC::R11));
}
} else if (RC == PPC::G8RCRegisterClass) {
if (DestReg != PPC::LR8) {
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::LD), DestReg),
FrameIdx));
} else {
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::LD), PPC::R11),
FrameIdx));
NewMIs.push_back(BuildMI(TII.get(PPC::MTLR8)).addReg(PPC::R11));
}
} else if (RC == PPC::F8RCRegisterClass) {
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::LFD), DestReg),
FrameIdx));
} else if (RC == PPC::F4RCRegisterClass) {
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::LFS), DestReg),
FrameIdx));
} else if (RC == PPC::CRRCRegisterClass) {
// FIXME: We use R0 here, because it isn't available for RA.
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::LWZ), PPC::R0),
FrameIdx));
// If the reloaded register isn't CR0, shift the bits right so that they are
// in the right CR's slot.
if (DestReg != PPC::CR0) {
unsigned ShiftBits = PPCRegisterInfo::getRegisterNumbering(DestReg)*4;
// rlwinm r11, r11, 32-ShiftBits, 0, 31.
NewMIs.push_back(BuildMI(TII.get(PPC::RLWINM), PPC::R0)
.addReg(PPC::R0).addImm(32-ShiftBits).addImm(0).addImm(31));
}
NewMIs.push_back(BuildMI(TII.get(PPC::MTCRF), DestReg).addReg(PPC::R0));
} else if (RC == PPC::VRRCRegisterClass) {
// We don't have indexed addressing for vector loads. Emit:
// R0 = ADDI FI#
// Dest = LVX 0, R0
//
// FIXME: We use R0 here, because it isn't available for RA.
NewMIs.push_back(addFrameReference(BuildMI(TII.get(PPC::ADDI), PPC::R0),
FrameIdx, 0, 0));
NewMIs.push_back(BuildMI(TII.get(PPC::LVX),DestReg).addReg(PPC::R0)
.addReg(PPC::R0));
} else {
assert(0 && "Unknown regclass!");
abort();
}
}
void
PPCInstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned DestReg, int FrameIdx,
const TargetRegisterClass *RC) const {
SmallVector<MachineInstr*, 4> NewMIs;
LoadRegFromStackSlot(*this, DestReg, FrameIdx, RC, NewMIs);
for (unsigned i = 0, e = NewMIs.size(); i != e; ++i)
MBB.insert(MI, NewMIs[i]);
}
void PPCInstrInfo::loadRegFromAddr(MachineFunction &MF, unsigned DestReg,
SmallVectorImpl<MachineOperand> &Addr,
const TargetRegisterClass *RC,
SmallVectorImpl<MachineInstr*> &NewMIs) const{
if (Addr[0].isFrameIndex()) {
LoadRegFromStackSlot(*this, DestReg, Addr[0].getIndex(), RC, NewMIs);
return;
}
unsigned Opc = 0;
if (RC == PPC::GPRCRegisterClass) {
assert(DestReg != PPC::LR && "Can't handle this yet!");
Opc = PPC::LWZ;
} else if (RC == PPC::G8RCRegisterClass) {
assert(DestReg != PPC::LR8 && "Can't handle this yet!");
Opc = PPC::LD;
} else if (RC == PPC::F8RCRegisterClass) {
Opc = PPC::LFD;
} else if (RC == PPC::F4RCRegisterClass) {
Opc = PPC::LFS;
} else if (RC == PPC::VRRCRegisterClass) {
Opc = PPC::LVX;
} else {
assert(0 && "Unknown regclass!");
abort();
}
MachineInstrBuilder MIB = BuildMI(get(Opc), DestReg);
for (unsigned i = 0, e = Addr.size(); i != e; ++i) {
MachineOperand &MO = Addr[i];
if (MO.isRegister())
MIB.addReg(MO.getReg());
else if (MO.isImmediate())
MIB.addImm(MO.getImm());
else
MIB.addFrameIndex(MO.getIndex());
}
NewMIs.push_back(MIB);
return;
}
/// foldMemoryOperand - PowerPC (like most RISC's) can only fold spills into
/// copy instructions, turning them into load/store instructions.
MachineInstr *PPCInstrInfo::foldMemoryOperand(MachineFunction &MF,
MachineInstr *MI,
SmallVectorImpl<unsigned> &Ops,
int FrameIndex) const {
if (Ops.size() != 1) return NULL;
// Make sure this is a reg-reg copy. Note that we can't handle MCRF, because
// it takes more than one instruction to store it.
unsigned Opc = MI->getOpcode();
unsigned OpNum = Ops[0];
MachineInstr *NewMI = NULL;
if ((Opc == PPC::OR &&
MI->getOperand(1).getReg() == MI->getOperand(2).getReg())) {
if (OpNum == 0) { // move -> store
unsigned InReg = MI->getOperand(1).getReg();
NewMI = addFrameReference(BuildMI(get(PPC::STW)).addReg(InReg),
FrameIndex);
} else { // move -> load
unsigned OutReg = MI->getOperand(0).getReg();
NewMI = addFrameReference(BuildMI(get(PPC::LWZ), OutReg),
FrameIndex);
}
} else if ((Opc == PPC::OR8 &&
MI->getOperand(1).getReg() == MI->getOperand(2).getReg())) {
if (OpNum == 0) { // move -> store
unsigned InReg = MI->getOperand(1).getReg();
NewMI = addFrameReference(BuildMI(get(PPC::STD)).addReg(InReg),
FrameIndex);
} else { // move -> load
unsigned OutReg = MI->getOperand(0).getReg();
NewMI = addFrameReference(BuildMI(get(PPC::LD), OutReg), FrameIndex);
}
} else if (Opc == PPC::FMRD) {
if (OpNum == 0) { // move -> store
unsigned InReg = MI->getOperand(1).getReg();
NewMI = addFrameReference(BuildMI(get(PPC::STFD)).addReg(InReg),
FrameIndex);
} else { // move -> load
unsigned OutReg = MI->getOperand(0).getReg();
NewMI = addFrameReference(BuildMI(get(PPC::LFD), OutReg), FrameIndex);
}
} else if (Opc == PPC::FMRS) {
if (OpNum == 0) { // move -> store
unsigned InReg = MI->getOperand(1).getReg();
NewMI = addFrameReference(BuildMI(get(PPC::STFS)).addReg(InReg),
FrameIndex);
} else { // move -> load
unsigned OutReg = MI->getOperand(0).getReg();
NewMI = addFrameReference(BuildMI(get(PPC::LFS), OutReg), FrameIndex);
}
}
if (NewMI)
NewMI->copyKillDeadInfo(MI);
return NewMI;
}
bool PPCInstrInfo::canFoldMemoryOperand(MachineInstr *MI,
SmallVectorImpl<unsigned> &Ops) const {
if (Ops.size() != 1) return false;
// Make sure this is a reg-reg copy. Note that we can't handle MCRF, because
// it takes more than one instruction to store it.
unsigned Opc = MI->getOpcode();
if ((Opc == PPC::OR &&
MI->getOperand(1).getReg() == MI->getOperand(2).getReg()))
return true;
else if ((Opc == PPC::OR8 &&
MI->getOperand(1).getReg() == MI->getOperand(2).getReg()))
return true;
else if (Opc == PPC::FMRD || Opc == PPC::FMRS)
return true;
return false;
}
bool PPCInstrInfo::BlockHasNoFallThrough(MachineBasicBlock &MBB) const {
if (MBB.empty()) return false;
switch (MBB.back().getOpcode()) {
case PPC::BLR: // Return.
case PPC::B: // Uncond branch.
case PPC::BCTR: // Indirect branch.
return true;
default: return false;
}
}
bool PPCInstrInfo::
ReverseBranchCondition(std::vector<MachineOperand> &Cond) const {
assert(Cond.size() == 2 && "Invalid PPC branch opcode!");
// Leave the CR# the same, but invert the condition.
Cond[0].setImm(PPC::InvertPredicate((PPC::Predicate)Cond[0].getImm()));
return false;
}