replica
/
hanchenye-llvm-project
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

- If fp (r7) is used to reference stack objects, use [r, r] address mode. 

- If there is a dynamic alloca, in the epilogue, restore the value of sp
  using r7 - offset.
- Other bug fixes.

llvm-svn: 33997
This commit is contained in:
Evan Cheng 2007-02-07 08:37:31 +00:00
parent 426fff7b42
commit b5519b5361
1 changed files with 67 additions and 28 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

95
llvm/lib/Target/ARM/ARMRegisterInfo.cpp
View File

@ -359,6 +359,19 @@ static unsigned calcNumMI(int Opc, int ExtraOpc, unsigned Bytes,
return NumMIs;
}
/// emitLoadConstPool - Emits a load from constpool to materialize NumBytes
/// immediate.
static void emitLoadConstPool(MachineBasicBlock &MBB,
MachineBasicBlock::iterator &MBBI,
unsigned DestReg, int NumBytes,
const TargetInstrInfo &TII) {
MachineFunction &MF = *MBB.getParent();
MachineConstantPool *ConstantPool = MF.getConstantPool();
Constant *C = ConstantInt::get(Type::Int32Ty, NumBytes);
unsigned Idx = ConstantPool->getConstantPoolIndex(C, 2);
BuildMI(MBB, MBBI, TII.get(ARM::tLDRpci), DestReg).addConstantPoolIndex(Idx);
}
/// emitThumbRegPlusConstPool - Emits a series of instructions to materialize
/// a destreg = basereg + immediate in Thumb code. Load the immediate from a
/// constpool entry.
@ -368,9 +381,8 @@ void emitThumbRegPlusConstPool(MachineBasicBlock &MBB,
unsigned DestReg, unsigned BaseReg,
int NumBytes, bool CanChangeCC,
const TargetInstrInfo &TII) {
MachineFunction &MF = *MBB.getParent();
MachineConstantPool *ConstantPool = MF.getConstantPool();
bool isHigh = !isLowRegister(DestReg) || !isLowRegister(BaseReg);
bool isHigh = !isLowRegister(DestReg) ||
(BaseReg != 0 && !isLowRegister(BaseReg));
bool isSub = false;
// Subtract doesn't have high register version. Load the negative value
// if either base or dest register is a high register. Also, if do not
@ -389,12 +401,9 @@ void emitThumbRegPlusConstPool(MachineBasicBlock &MBB,
if (NumBytes <= 255 && NumBytes >= 0)
BuildMI(MBB, MBBI, TII.get(ARM::tMOVri8), LdReg).addImm(NumBytes);
else {
// Load the constant.
Constant *C = ConstantInt::get(Type::Int32Ty, NumBytes);
unsigned Idx = ConstantPool->getConstantPoolIndex(C, 2);
BuildMI(MBB, MBBI, TII.get(ARM::tLDRpci), LdReg).addConstantPoolIndex(Idx);
}
else
emitLoadConstPool(MBB, MBBI, LdReg, NumBytes, TII);
// Emit add / sub.
int Opc = (isSub) ? ARM::tSUBrr : (isHigh ? ARM::tADDhirr : ARM::tADDrr);
const MachineInstrBuilder MIB = BuildMI(MBB, MBBI, TII.get(Opc), DestReg);
@ -721,8 +730,8 @@ void ARMRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II) const{
case ARMII::AddrModeTs: {
ImmIdx = i+1;
InstrOffs = MI.getOperand(ImmIdx).getImm();
NumBits = isSub ? 3 : ((FrameReg == ARM::SP) ? 8 : 5);
Scale = isSub ? 1 : 4;
NumBits = (FrameReg == ARM::SP) ? 8 : 5;
Scale = 4;
break;
}
default:
@ -754,7 +763,7 @@ void ARMRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II) const{
// If this is a thumb spill / restore, we will be using a constpool load to
// materialize the offset.
bool isThumSpillRestore = Opcode == ARM::tRestore || Opcode == ARM::tSpill;
if (AddrMode == ARMII::AddrModeTs || !isThumSpillRestore) {
if (AddrMode == ARMII::AddrModeTs && !isThumSpillRestore) {
if (AddrMode == ARMII::AddrModeTs) {
// Thumb tLDRspi, tSTRspi. These will change to instructions that use
// a different base register.
@ -779,12 +788,21 @@ void ARMRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II) const{
if (TII.isLoad(Opcode)) {
// Use the destination register to materialize sp + offset.
unsigned TmpReg = MI.getOperand(0).getReg();
if (Opcode == ARM::tRestore)
emitThumbRegPlusConstPool(MBB, II, TmpReg, FrameReg, Offset, false, TII);
else
bool UseRR = false;
if (Opcode == ARM::tRestore) {
if (FrameReg == ARM::SP)
emitThumbRegPlusConstPool(MBB, II, TmpReg, FrameReg,Offset,false,TII);
else {
emitLoadConstPool(MBB, II, TmpReg, Offset, TII);
UseRR = true;
}
} else
emitThumbRegPlusImmediate(MBB, II, TmpReg, FrameReg, Offset, TII);
MI.setInstrDescriptor(TII.get(ARM::tLDR));
MI.getOperand(i).ChangeToRegister(TmpReg, false);
if (UseRR)
MI.addRegOperand(FrameReg, false); // Use [reg, reg] addrmode.
else
MI.addRegOperand(0, false); // tLDR has an extra register operand.
} else if (TII.isStore(Opcode)) {
// FIXME! This is horrific!!! We need register scavenging.
@ -797,19 +815,30 @@ void ARMRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II) const{
// r2 = r12
unsigned ValReg = MI.getOperand(0).getReg();
unsigned TmpReg = ARM::R3;
bool UseRR = false;
if (ValReg == ARM::R3) {
BuildMI(MBB, II, TII.get(ARM::tMOVrr), ARM::R12).addReg(ARM::R2);
TmpReg = ARM::R2;
}
if (Opcode == ARM::tSpill)
emitThumbRegPlusConstPool(MBB, II, TmpReg, FrameReg, Offset, false, TII);
else
if (Opcode == ARM::tSpill) {
if (FrameReg == ARM::SP)
emitThumbRegPlusConstPool(MBB, II, TmpReg, FrameReg,Offset,false,TII);
else {
emitLoadConstPool(MBB, II, TmpReg, Offset, TII);
UseRR = true;
}
} else
emitThumbRegPlusImmediate(MBB, II, TmpReg, FrameReg, Offset, TII);
MI.setInstrDescriptor(TII.get(ARM::tSTR));
MI.getOperand(i).ChangeToRegister(TmpReg, false);
MI.addRegOperand(0, false); // tSTR has an extra register operand.
if (ValReg == ARM::R3)
BuildMI(MBB, II, TII.get(ARM::tMOVrr), ARM::R2).addReg(ARM::R12);
if (UseRR)
MI.addRegOperand(FrameReg, false); // Use [reg, reg] addrmode.
else
MI.addRegOperand(0, false); // tSTR has an extra register operand.
if (ValReg == ARM::R3) {
MachineBasicBlock::iterator NII = next(II);
BuildMI(MBB, NII, TII.get(ARM::tMOVrr), ARM::R2).addReg(ARM::R12);
}
} else
assert(false && "Unexpected opcode!");
} else {
@ -1152,13 +1181,23 @@ void ARMRegisterInfo::emitEpilogue(MachineFunction &MF,
AFI->getGPRCalleeSavedArea2Size() +
AFI->getDPRCalleeSavedAreaSize());
if (isThumb) {
if (MBBI->getOpcode() == ARM::tBX_RET &&
&MBB.front() != MBBI &&
prior(MBBI)->getOpcode() == ARM::tPOP) {
MachineBasicBlock::iterator PMBBI = prior(MBBI);
emitSPUpdate(MBB, PMBBI, NumBytes, isThumb, TII);
} else
emitSPUpdate(MBB, MBBI, NumBytes, isThumb, TII);
if (hasFP(MF)) {
NumBytes = AFI->getFramePtrSpillOffset() - NumBytes;
// Reset SP based on frame pointer only if the stack frame extends beyond
// frame pointer stack slot or target is ELF and the function has FP.
if (NumBytes)
emitThumbRegPlusImmediate(MBB, MBBI, ARM::SP, FramePtr, -NumBytes, TII);
else
BuildMI(MBB, MBBI, TII.get(ARM::tMOVrr), ARM::SP).addReg(FramePtr);
} else {
if (MBBI->getOpcode() == ARM::tBX_RET &&
&MBB.front() != MBBI &&
prior(MBBI)->getOpcode() == ARM::tPOP) {
MachineBasicBlock::iterator PMBBI = prior(MBBI);
emitSPUpdate(MBB, PMBBI, NumBytes, isThumb, TII);
} else
emitSPUpdate(MBB, MBBI, NumBytes, isThumb, TII);
}
} else {
// Darwin ABI requires FP to point to the stack slot that contains the
// previous FP.