-void
-PPCRegisterInfo::emitPrologue(MachineFunction &MF) const {
- MachineBasicBlock &MBB = MF.front(); // Prolog goes in entry BB
- MachineBasicBlock::iterator MBBI = MBB.begin();
- MachineFrameInfo *MFI = MF.getFrameInfo();
- MachineModuleInfo *MMI = MFI->getMachineModuleInfo();
- bool needsFrameMoves = (MMI && MMI->hasDebugInfo()) ||
- !MF.getFunction()->doesNotThrow() ||
- !UnwindTablesOptional;
-
- // Prepare for frame info.
- unsigned FrameLabelId = 0;
-
- // Scan the prolog, looking for an UPDATE_VRSAVE instruction. If we find it,
- // process it.
- for (unsigned i = 0; MBBI != MBB.end(); ++i, ++MBBI) {
- if (MBBI->getOpcode() == PPC::UPDATE_VRSAVE) {
- HandleVRSaveUpdate(MBBI, TII);
- break;
- }
- }
-
- // Move MBBI back to the beginning of the function.
- MBBI = MBB.begin();
-
- // Work out frame sizes.
- determineFrameLayout(MF);
- unsigned FrameSize = MFI->getStackSize();
-
- int NegFrameSize = -FrameSize;
-
- // Get processor type.
- bool IsPPC64 = Subtarget.isPPC64();
- // Get operating system
- bool IsMachoABI = Subtarget.isMachoABI();
- // Check if the link register (LR) has been used.
- bool UsesLR = MustSaveLR(MF);
- // Do we have a frame pointer for this function?
- bool HasFP = hasFP(MF) && FrameSize;
-
- int LROffset = PPCFrameInfo::getReturnSaveOffset(IsPPC64, IsMachoABI);
- int FPOffset = PPCFrameInfo::getFramePointerSaveOffset(IsPPC64, IsMachoABI);
-
- if (IsPPC64) {
- if (UsesLR)
- BuildMI(MBB, MBBI, TII.get(PPC::MFLR8), PPC::X0);
-
- if (HasFP)
- BuildMI(MBB, MBBI, TII.get(PPC::STD))
- .addReg(PPC::X31)
- .addImm(FPOffset/4)
- .addReg(PPC::X1);
-
- if (UsesLR)
- BuildMI(MBB, MBBI, TII.get(PPC::STD))
- .addReg(PPC::X0)
- .addImm(LROffset / 4)
- .addReg(PPC::X1);
- } else {
- if (UsesLR)
- BuildMI(MBB, MBBI, TII.get(PPC::MFLR), PPC::R0);
-
- if (HasFP)
- BuildMI(MBB, MBBI, TII.get(PPC::STW))
- .addReg(PPC::R31)
- .addImm(FPOffset)
- .addReg(PPC::R1);
-
- if (UsesLR)
- BuildMI(MBB, MBBI, TII.get(PPC::STW))
- .addReg(PPC::R0)
- .addImm(LROffset)
- .addReg(PPC::R1);
- }
-
- // Skip if a leaf routine.
- if (!FrameSize) return;
-
- // Get stack alignments.
- unsigned TargetAlign = MF.getTarget().getFrameInfo()->getStackAlignment();
- unsigned MaxAlign = MFI->getMaxAlignment();
-
- if (needsFrameMoves) {
- // Mark effective beginning of when frame pointer becomes valid.
- FrameLabelId = MMI->NextLabelID();
- BuildMI(MBB, MBBI, TII.get(PPC::LABEL)).addImm(FrameLabelId).addImm(0);
- }
-
- // Adjust stack pointer: r1 += NegFrameSize.
- // If there is a preferred stack alignment, align R1 now
- if (!IsPPC64) {
- // PPC32.
- if (ALIGN_STACK && MaxAlign > TargetAlign) {
- assert(isPowerOf2_32(MaxAlign)&&isInt16(MaxAlign)&&"Invalid alignment!");
- assert(isInt16(NegFrameSize) && "Unhandled stack size and alignment!");
-
- BuildMI(MBB, MBBI, TII.get(PPC::RLWINM), PPC::R0)
- .addReg(PPC::R1)
- .addImm(0)
- .addImm(32 - Log2_32(MaxAlign))
- .addImm(31);
- BuildMI(MBB, MBBI, TII.get(PPC::SUBFIC) ,PPC::R0)
- .addReg(PPC::R0, false, false, true)
- .addImm(NegFrameSize);
- BuildMI(MBB, MBBI, TII.get(PPC::STWUX))
- .addReg(PPC::R1)
- .addReg(PPC::R1)
- .addReg(PPC::R0);
- } else if (isInt16(NegFrameSize)) {
- BuildMI(MBB, MBBI, TII.get(PPC::STWU), PPC::R1)
- .addReg(PPC::R1)
- .addImm(NegFrameSize)
- .addReg(PPC::R1);
- } else {
- BuildMI(MBB, MBBI, TII.get(PPC::LIS), PPC::R0)
- .addImm(NegFrameSize >> 16);
- BuildMI(MBB, MBBI, TII.get(PPC::ORI), PPC::R0)
- .addReg(PPC::R0, false, false, true)
- .addImm(NegFrameSize & 0xFFFF);
- BuildMI(MBB, MBBI, TII.get(PPC::STWUX))
- .addReg(PPC::R1)
- .addReg(PPC::R1)
- .addReg(PPC::R0);
- }
- } else { // PPC64.
- if (ALIGN_STACK && MaxAlign > TargetAlign) {
- assert(isPowerOf2_32(MaxAlign)&&isInt16(MaxAlign)&&"Invalid alignment!");
- assert(isInt16(NegFrameSize) && "Unhandled stack size and alignment!");
-
- BuildMI(MBB, MBBI, TII.get(PPC::RLDICL), PPC::X0)
- .addReg(PPC::X1)
- .addImm(0)
- .addImm(64 - Log2_32(MaxAlign));
- BuildMI(MBB, MBBI, TII.get(PPC::SUBFIC8), PPC::X0)
- .addReg(PPC::X0)
- .addImm(NegFrameSize);
- BuildMI(MBB, MBBI, TII.get(PPC::STDUX))
- .addReg(PPC::X1)
- .addReg(PPC::X1)
- .addReg(PPC::X0);
- } else if (isInt16(NegFrameSize)) {
- BuildMI(MBB, MBBI, TII.get(PPC::STDU), PPC::X1)
- .addReg(PPC::X1)
- .addImm(NegFrameSize / 4)
- .addReg(PPC::X1);
- } else {
- BuildMI(MBB, MBBI, TII.get(PPC::LIS8), PPC::X0)
- .addImm(NegFrameSize >> 16);
- BuildMI(MBB, MBBI, TII.get(PPC::ORI8), PPC::X0)
- .addReg(PPC::X0, false, false, true)
- .addImm(NegFrameSize & 0xFFFF);
- BuildMI(MBB, MBBI, TII.get(PPC::STDUX))
- .addReg(PPC::X1)
- .addReg(PPC::X1)
- .addReg(PPC::X0);
- }
- }
-
- if (needsFrameMoves) {
- std::vector<MachineMove> &Moves = MMI->getFrameMoves();
-
- if (NegFrameSize) {
- // Show update of SP.
- MachineLocation SPDst(MachineLocation::VirtualFP);
- MachineLocation SPSrc(MachineLocation::VirtualFP, NegFrameSize);
- Moves.push_back(MachineMove(FrameLabelId, SPDst, SPSrc));
- } else {
- MachineLocation SP(IsPPC64 ? PPC::X31 : PPC::R31);
- Moves.push_back(MachineMove(FrameLabelId, SP, SP));
- }
-
- if (HasFP) {
- MachineLocation FPDst(MachineLocation::VirtualFP, FPOffset);
- MachineLocation FPSrc(IsPPC64 ? PPC::X31 : PPC::R31);
- Moves.push_back(MachineMove(FrameLabelId, FPDst, FPSrc));
- }
-
- // Add callee saved registers to move list.
- const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
- for (unsigned I = 0, E = CSI.size(); I != E; ++I) {
- int Offset = MFI->getObjectOffset(CSI[I].getFrameIdx());
- unsigned Reg = CSI[I].getReg();
- if (Reg == PPC::LR || Reg == PPC::LR8) continue;
- MachineLocation CSDst(MachineLocation::VirtualFP, Offset);
- MachineLocation CSSrc(Reg);
- Moves.push_back(MachineMove(FrameLabelId, CSDst, CSSrc));
- }
-
- MachineLocation LRDst(MachineLocation::VirtualFP, LROffset);
- MachineLocation LRSrc(IsPPC64 ? PPC::LR8 : PPC::LR);
- Moves.push_back(MachineMove(FrameLabelId, LRDst, LRSrc));
-
- // Mark effective beginning of when frame pointer is ready.
- unsigned ReadyLabelId = MMI->NextLabelID();
- BuildMI(MBB, MBBI, TII.get(PPC::LABEL)).addImm(ReadyLabelId).addImm(0);
-
- MachineLocation FPDst(HasFP ? (IsPPC64 ? PPC::X31 : PPC::R31) :
- (IsPPC64 ? PPC::X1 : PPC::R1));
- MachineLocation FPSrc(MachineLocation::VirtualFP);
- Moves.push_back(MachineMove(ReadyLabelId, FPDst, FPSrc));
- }
-
- // If there is a frame pointer, copy R1 into R31
- if (HasFP) {
- if (!IsPPC64) {
- BuildMI(MBB, MBBI, TII.get(PPC::OR), PPC::R31)
- .addReg(PPC::R1)
- .addReg(PPC::R1);
- } else {
- BuildMI(MBB, MBBI, TII.get(PPC::OR8), PPC::X31)
- .addReg(PPC::X1)
- .addReg(PPC::X1);
- }
- }