diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Target/PowerPC/PowerPCRegisterInfo.cpp | 32 |
1 files changed, 21 insertions, 11 deletions
diff --git a/lib/Target/PowerPC/PowerPCRegisterInfo.cpp b/lib/Target/PowerPC/PowerPCRegisterInfo.cpp index a9157ed921..2095084741 100644 --- a/lib/Target/PowerPC/PowerPCRegisterInfo.cpp +++ b/lib/Target/PowerPC/PowerPCRegisterInfo.cpp @@ -196,7 +196,7 @@ void PowerPCRegisterInfo::emitPrologue(MachineFunction &MF) const { unsigned NumBytes = MFI->getStackSize(); // If we have calls, save the LR value on the stack - if (MFI->hasCalls()) { + if (MFI->hasCalls() || true) { // When we have no frame pointer, we reserve argument space for call sites // in the function immediately on entry to the current function. This // eliminates the need for add/sub brackets around call sites. @@ -254,25 +254,35 @@ void PowerPCRegisterInfo::emitEpilogue(MachineFunction &MF, // Get the number of bytes allocated from the FrameInfo... unsigned NumBytes = MFI->getStackSize(); - // If we have calls, restore the LR value before we branch to it - if (MFI->hasCalls()) { - // Restore LR + if (NumBytes == 0 && (MFI->hasCalls() || true)) { + // Don't need to adjust the stack pointer, just gotta fix up the LR 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) { + } else if (NumBytes <= 32767-8) { + // We're within range to load the return address and restore the stack + // pointer with immediate offsets only. + if (MFI->hasCalls() || true) { + 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); + } MI = BuildMI(PPC32::ADDI, 2, PPC32::R1).addReg(PPC32::R1).addSImm(NumBytes); MBB.insert(MBBI, MI); } else { MI = BuildMI(PPC32::LWZ, 2, PPC32::R1).addSImm(0).addReg(PPC32::R1); MBB.insert(MBBI, MI); + // We're not within range to load the return address with an immediate + // offset before restoring the stack pointer, so do it after from its spot + // in the linkage area. + if (MFI->hasCalls() || true) { + MI = BuildMI(PPC32::LWZ, 2, PPC32::R0).addSImm(8).addReg(PPC32::R1); + MBB.insert(MBBI, MI); + MI = BuildMI(PPC32::MTLR, 1).addReg(PPC32::R0); + MBB.insert(MBBI, MI); + } } } |