Do not store the stack pointer if the stack size is 0.

Also, convert C-style comments to C++ and make sure code wraps at 80 cols.

llvm-svn: 15245
This commit is contained in:
Misha Brukman 2004-07-26 22:00:26 +00:00
parent a979e8a08a
commit 6272268028

View File

@ -166,7 +166,7 @@ PowerPCRegisterInfo::eliminateFrameIndex(MachineFunction &MF,
if (!hasFP(MF))
Offset += MF.getFrameInfo()->getStackSize();
MI.SetMachineOperandConst(OffIdx, MachineOperand::MO_SignExtendedImmed, Offset);
MI.SetMachineOperandConst(OffIdx,MachineOperand::MO_SignExtendedImmed,Offset);
DEBUG(std::cerr << "offset = " << Offset << std::endl);
}
@ -195,13 +195,12 @@ void PowerPCRegisterInfo::emitPrologue(MachineFunction &MF) const {
// eliminates the need for add/sub brackets around call sites.
//
NumBytes += MFI->getMaxCallFrameSize() +
24 /* Predefined PowerPC link area */ +
32 /* Predefined PowerPC params area */ +
0 /* local variables - managed by llvm*/ +
0 * 4 /* volatile GPRs used - managed by llvm */ +
0 * 8 /* volatile FPRs used - managed by llvm */;
24 + // Predefined PowerPC link area
32 + // Predefined PowerPC params area
0 + // local variables - managed by LLVM
0 * 4 + // volatile GPRs used - managed by LLVM
0 * 8; // volatile FPRs used - managed by LLVM
// Round the size to a multiple of the alignment (don't forget the 4 byte
// offset though).
unsigned Align = MF.getTarget().getFrameInfo()->getStackAlignment();
@ -217,6 +216,9 @@ void PowerPCRegisterInfo::emitPrologue(MachineFunction &MF) const {
// Update frame info to pretend that this is part of the stack...
MFI->setStackSize(NumBytes);
// Do we need to allocate space on the stack?
if (NumBytes == 0) return;
// adjust stack pointer: r1 -= numbytes
if (NumBytes <= 32768) {
MI = BuildMI(PPC32::STWU, 3).addReg(PPC32::R1).addSImm(-NumBytes)
@ -252,11 +254,15 @@ void PowerPCRegisterInfo::emitEpilogue(MachineFunction &MF,
// conservative.
if (MFI->hasCalls() || true) {
// Restore LR
MI = BuildMI(PPC32::LWZ, 2, PPC32::R0).addSImm(NumBytes+8).addReg(PPC32::R1);
MI = BuildMI(PPC32::LWZ, 2,PPC32::R0).addSImm(NumBytes+8).addReg(PPC32::R1);
MBB.insert(MBBI, MI);
MI = BuildMI(PPC32::MTLR, 1).addReg(PPC32::R0);
MBB.insert(MBBI, MI);
}
// Do we need to adjust the stack pointer back?
if (NumBytes == 0) return;
// Adjust stack pointer back
if (NumBytes <= 32767) {
MI = BuildMI(PPC32::ADDI, 2, PPC32::R1).addReg(PPC32::R1).addSImm(NumBytes);