Changes in directory llvm/lib/Target/PowerPC:
PPCRegisterInfo.cpp updated: 1.39 -> 1.40 --- Log message: If a function has a non-zero sized frame, use an add to adjust the stack pointer in the epilog, not a load. --- Diffs of the changes: (+20 -9) PPCRegisterInfo.cpp | 29 ++++++++++++++++++++--------- 1 files changed, 20 insertions(+), 9 deletions(-) Index: llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp diff -u llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp:1.39 llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp:1.40 --- llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp:1.39 Mon Jan 9 12:28:21 2006 +++ llvm/lib/Target/PowerPC/PPCRegisterInfo.cpp Wed Jan 11 17:03:54 2006 @@ -370,23 +370,34 @@ void PPCRegisterInfo::emitEpilogue(MachineFunction &MF, MachineBasicBlock &MBB) const { - const MachineFrameInfo *MFI = MF.getFrameInfo(); MachineBasicBlock::iterator MBBI = prior(MBB.end()); - MachineInstr *MI; assert(MBBI->getOpcode() == PPC::BLR && "Can only insert epilog into returning blocks"); - // Get the number of bytes allocated from the FrameInfo... - unsigned NumBytes = MFI->getStackSize(); - unsigned GPRSize = 4; + // Get the number of bytes allocated from the FrameInfo. + unsigned NumBytes = MF.getFrameInfo()->getStackSize(); + unsigned GPRSize = 4; if (NumBytes != 0) { + // If this function has a frame pointer, load the saved stack pointer from + // its stack slot. if (hasFP(MF)) { - MI = BuildMI(PPC::LWZ, 2, PPC::R31).addSImm(GPRSize).addReg(PPC::R31); - MBB.insert(MBBI, MI); + BuildMI(MBB, MBBI, PPC::LWZ, 2, PPC::R31) + .addSImm(GPRSize).addReg(PPC::R31); + } + + // The loaded (or persistent) stack pointer value is offseted by the 'stwu' + // on entry to the function. Add this offset back now. + if (NumBytes <= 32768) { + BuildMI(MBB, MBBI, PPC::ADDI, 2, PPC::R1) + .addReg(PPC::R1).addSImm(NumBytes); + } else { + BuildMI(MBB, MBBI, PPC::LIS, 1, PPC::R0).addSImm(NumBytes >> 16); + BuildMI(MBB, MBBI, PPC::ORI, 2, PPC::R0) + .addReg(PPC::R0).addImm(NumBytes & 0xFFFF); + BuildMI(MBB, MBBI, PPC::ADD4, 2, PPC::R1) + .addReg(PPC::R0).addReg(PPC::R1); } - MI = BuildMI(PPC::LWZ, 2, PPC::R1).addSImm(0).addReg(PPC::R1); - MBB.insert(MBBI, MI); } } _______________________________________________ llvm-commits mailing list llvm-commits@cs.uiuc.edu http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits