eliminateFrameIndex() bug when frame pointer is used as base register.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33945 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2007-02-06 00:23:31 +00:00
parent ad0e465889
commit 88b633165a

View File

@ -386,6 +386,8 @@ void emitThumbRegPlusConstPool(MachineBasicBlock &MBB,
const MachineInstrBuilder MIB = BuildMI(MBB, MBBI, TII.get(Opc), DestReg);
if (DestReg == ARM::SP)
MIB.addReg(BaseReg).addReg(LdReg);
else if (isSub)
MIB.addReg(BaseReg).addReg(LdReg);
else
MIB.addReg(LdReg).addReg(BaseReg);
if (DestReg == ARM::SP)
@ -647,7 +649,7 @@ void ARMRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II) const{
// MI would expand into a large number of instructions. Don't try to
// simplify the immediate.
if (NumMIs > 2) {
emitThumbRegPlusImmediate(MBB, II, DestReg, ARM::SP, Offset, TII);
emitThumbRegPlusImmediate(MBB, II, DestReg, FrameReg, Offset, TII);
MBB.erase(II);
return;
}
@ -705,7 +707,7 @@ void ARMRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II) const{
case ARMII::AddrModeTs: {
ImmIdx = i+1;
InstrOffs = MI.getOperand(ImmIdx).getImm();
NumBits = 8;
NumBits = (FrameReg == ARM::SP) ? 8 : 5;
Scale = 4;
break;
}
@ -722,31 +724,33 @@ void ARMRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II) const{
isSub = true;
}
MachineOperand &ImmOp = MI.getOperand(ImmIdx);
int ImmedOffset = Offset / Scale;
unsigned Mask = (1 << NumBits) - 1;
if ((unsigned)Offset <= Mask * Scale) {
// Replace the FrameIndex with sp
MI.getOperand(i).ChangeToRegister(FrameReg, false);
if (!isSub || !isThumb) {
MachineOperand &ImmOp = MI.getOperand(ImmIdx);
int ImmedOffset = Offset / Scale;
unsigned Mask = (1 << NumBits) - 1;
if ((unsigned)Offset <= Mask * Scale) {
// Replace the FrameIndex with sp
MI.getOperand(i).ChangeToRegister(FrameReg, false);
if (isSub)
ImmedOffset |= 1 << NumBits;
ImmOp.ChangeToImmediate(ImmedOffset);
return;
}
// Otherwise, it didn't fit. Pull in what we can to simplify the immed.
if (AddrMode == ARMII::AddrModeTs) {
// Thumb tLDRspi, tSTRspi. These will change to instructions that use
// a different base register.
NumBits = 5;
Mask = (1 << NumBits) - 1;
}
ImmedOffset = ImmedOffset & Mask;
if (isSub)
ImmedOffset |= 1 << NumBits;
ImmOp.ChangeToImmediate(ImmedOffset);
return;
Offset &= ~(Mask*Scale);
}
// Otherwise, it didn't fit. Pull in what we can to simplify the immediate.
if (AddrMode == ARMII::AddrModeTs) {
// Thumb tLDRspi, tSTRspi. These will change to instructions that use a
// different base register.
NumBits = 5;
Mask = (1 << NumBits) - 1;
}
ImmedOffset = ImmedOffset & Mask;
if (isSub)
ImmedOffset |= 1 << NumBits;
ImmOp.ChangeToImmediate(ImmedOffset);
Offset &= ~(Mask*Scale);
}
// If we get here, the immediate doesn't fit into the instruction. We folded