Ejemplo n.º 1
0
void MIRPrinter::convert(ModuleSlotTracker &MST,
                         yaml::MachineFrameInfo &YamlMFI,
                         const MachineFrameInfo &MFI) {
  YamlMFI.IsFrameAddressTaken = MFI.isFrameAddressTaken();
  YamlMFI.IsReturnAddressTaken = MFI.isReturnAddressTaken();
  YamlMFI.HasStackMap = MFI.hasStackMap();
  YamlMFI.HasPatchPoint = MFI.hasPatchPoint();
  YamlMFI.StackSize = MFI.getStackSize();
  YamlMFI.OffsetAdjustment = MFI.getOffsetAdjustment();
  YamlMFI.MaxAlignment = MFI.getMaxAlignment();
  YamlMFI.AdjustsStack = MFI.adjustsStack();
  YamlMFI.HasCalls = MFI.hasCalls();
  YamlMFI.MaxCallFrameSize = MFI.getMaxCallFrameSize();
  YamlMFI.HasOpaqueSPAdjustment = MFI.hasOpaqueSPAdjustment();
  YamlMFI.HasVAStart = MFI.hasVAStart();
  YamlMFI.HasMustTailInVarArgFunc = MFI.hasMustTailInVarArgFunc();
  if (MFI.getSavePoint()) {
    raw_string_ostream StrOS(YamlMFI.SavePoint.Value);
    MIPrinter(StrOS, MST, RegisterMaskIds, StackObjectOperandMapping)
        .printMBBReference(*MFI.getSavePoint());
  }
  if (MFI.getRestorePoint()) {
    raw_string_ostream StrOS(YamlMFI.RestorePoint.Value);
    MIPrinter(StrOS, MST, RegisterMaskIds, StackObjectOperandMapping)
        .printMBBReference(*MFI.getRestorePoint());
  }
}
Ejemplo n.º 2
0
void MIRPrinter::convert(ModuleSlotTracker &MST,
                         yaml::MachineFrameInfo &YamlMFI,
                         const MachineFrameInfo &MFI) {
  YamlMFI.IsFrameAddressTaken = MFI.isFrameAddressTaken();
  YamlMFI.IsReturnAddressTaken = MFI.isReturnAddressTaken();
  YamlMFI.HasStackMap = MFI.hasStackMap();
  YamlMFI.HasPatchPoint = MFI.hasPatchPoint();
  YamlMFI.StackSize = MFI.getStackSize();
  YamlMFI.OffsetAdjustment = MFI.getOffsetAdjustment();
  YamlMFI.MaxAlignment = MFI.getMaxAlignment();
  YamlMFI.AdjustsStack = MFI.adjustsStack();
  YamlMFI.HasCalls = MFI.hasCalls();
  YamlMFI.MaxCallFrameSize = MFI.isMaxCallFrameSizeComputed()
    ? MFI.getMaxCallFrameSize() : ~0u;
  YamlMFI.CVBytesOfCalleeSavedRegisters =
      MFI.getCVBytesOfCalleeSavedRegisters();
  YamlMFI.HasOpaqueSPAdjustment = MFI.hasOpaqueSPAdjustment();
  YamlMFI.HasVAStart = MFI.hasVAStart();
  YamlMFI.HasMustTailInVarArgFunc = MFI.hasMustTailInVarArgFunc();
  YamlMFI.LocalFrameSize = MFI.getLocalFrameSize();
  if (MFI.getSavePoint()) {
    raw_string_ostream StrOS(YamlMFI.SavePoint.Value);
    StrOS << printMBBReference(*MFI.getSavePoint());
  }
  if (MFI.getRestorePoint()) {
    raw_string_ostream StrOS(YamlMFI.RestorePoint.Value);
    StrOS << printMBBReference(*MFI.getRestorePoint());
  }
}
Ejemplo n.º 3
0
void MIRPrinter::convert(yaml::MachineFrameInfo &YamlMFI,
                         const MachineFrameInfo &MFI) {
    YamlMFI.IsFrameAddressTaken = MFI.isFrameAddressTaken();
    YamlMFI.IsReturnAddressTaken = MFI.isReturnAddressTaken();
    YamlMFI.HasStackMap = MFI.hasStackMap();
    YamlMFI.HasPatchPoint = MFI.hasPatchPoint();
    YamlMFI.StackSize = MFI.getStackSize();
    YamlMFI.OffsetAdjustment = MFI.getOffsetAdjustment();
    YamlMFI.MaxAlignment = MFI.getMaxAlignment();
    YamlMFI.AdjustsStack = MFI.adjustsStack();
    YamlMFI.HasCalls = MFI.hasCalls();
    YamlMFI.MaxCallFrameSize = MFI.getMaxCallFrameSize();
    YamlMFI.HasOpaqueSPAdjustment = MFI.hasOpaqueSPAdjustment();
    YamlMFI.HasVAStart = MFI.hasVAStart();
    YamlMFI.HasMustTailInVarArgFunc = MFI.hasMustTailInVarArgFunc();
}
Ejemplo n.º 4
0
int SystemZRegisterInfo::getFrameIndexOffset(MachineFunction &MF, int FI) const {
  const TargetFrameInfo &TFI = *MF.getTarget().getFrameInfo();
  MachineFrameInfo *MFI = MF.getFrameInfo();
  SystemZMachineFunctionInfo *SystemZMFI =
    MF.getInfo<SystemZMachineFunctionInfo>();
  int Offset = MFI->getObjectOffset(FI) + MFI->getOffsetAdjustment();
  uint64_t StackSize = MFI->getStackSize();

  // Fixed objects are really located in the "previous" frame.
  if (FI < 0)
    StackSize -= SystemZMFI->getCalleeSavedFrameSize();

  Offset += StackSize - TFI.getOffsetOfLocalArea();

  // Skip the register save area if we generated the stack frame.
  if (StackSize || MFI->hasCalls())
    Offset -= TFI.getOffsetOfLocalArea();

  return Offset;
}
void Thumb1FrameLowering::emitPrologue(MachineFunction &MF,
                                       MachineBasicBlock &MBB) const {
  MachineBasicBlock::iterator MBBI = MBB.begin();
  MachineFrameInfo  *MFI = MF.getFrameInfo();
  ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
  MachineModuleInfo &MMI = MF.getMMI();
  const MCRegisterInfo *MRI = MMI.getContext().getRegisterInfo();
  const ThumbRegisterInfo *RegInfo =
      static_cast<const ThumbRegisterInfo *>(STI.getRegisterInfo());
  const Thumb1InstrInfo &TII =
      *static_cast<const Thumb1InstrInfo *>(STI.getInstrInfo());

  unsigned ArgRegsSaveSize = AFI->getArgRegsSaveSize();
  unsigned NumBytes = MFI->getStackSize();
  assert(NumBytes >= ArgRegsSaveSize &&
         "ArgRegsSaveSize is included in NumBytes");
  const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();

  // Debug location must be unknown since the first debug location is used
  // to determine the end of the prologue.
  DebugLoc dl;
  
  unsigned FramePtr = RegInfo->getFrameRegister(MF);
  unsigned BasePtr = RegInfo->getBaseRegister();
  int CFAOffset = 0;

  // Thumb add/sub sp, imm8 instructions implicitly multiply the offset by 4.
  NumBytes = (NumBytes + 3) & ~3;
  MFI->setStackSize(NumBytes);

  // Determine the sizes of each callee-save spill areas and record which frame
  // belongs to which callee-save spill areas.
  unsigned GPRCS1Size = 0, GPRCS2Size = 0, DPRCSSize = 0;
  int FramePtrSpillFI = 0;

  if (ArgRegsSaveSize) {
    emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -ArgRegsSaveSize,
                 MachineInstr::FrameSetup);
    CFAOffset -= ArgRegsSaveSize;
    unsigned CFIIndex = MMI.addFrameInst(
        MCCFIInstruction::createDefCfaOffset(nullptr, CFAOffset));
    BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
        .addCFIIndex(CFIIndex)
        .setMIFlags(MachineInstr::FrameSetup);
  }

  if (!AFI->hasStackFrame()) {
    if (NumBytes - ArgRegsSaveSize != 0) {
      emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -(NumBytes - ArgRegsSaveSize),
                   MachineInstr::FrameSetup);
      CFAOffset -= NumBytes - ArgRegsSaveSize;
      unsigned CFIIndex = MMI.addFrameInst(
          MCCFIInstruction::createDefCfaOffset(nullptr, CFAOffset));
      BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
          .addCFIIndex(CFIIndex)
          .setMIFlags(MachineInstr::FrameSetup);
    }
    return;
  }

  for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
    unsigned Reg = CSI[i].getReg();
    int FI = CSI[i].getFrameIdx();
    switch (Reg) {
    case ARM::R8:
    case ARM::R9:
    case ARM::R10:
    case ARM::R11:
      if (STI.isTargetMachO()) {
        GPRCS2Size += 4;
        break;
      }
      // fallthrough
    case ARM::R4:
    case ARM::R5:
    case ARM::R6:
    case ARM::R7:
    case ARM::LR:
      if (Reg == FramePtr)
        FramePtrSpillFI = FI;
      GPRCS1Size += 4;
      break;
    default:
      DPRCSSize += 8;
    }
  }

  if (MBBI != MBB.end() && MBBI->getOpcode() == ARM::tPUSH) {
    ++MBBI;
  }

  // Determine starting offsets of spill areas.
  unsigned DPRCSOffset  = NumBytes - ArgRegsSaveSize - (GPRCS1Size + GPRCS2Size + DPRCSSize);
  unsigned GPRCS2Offset = DPRCSOffset + DPRCSSize;
  unsigned GPRCS1Offset = GPRCS2Offset + GPRCS2Size;
  bool HasFP = hasFP(MF);
  if (HasFP)
    AFI->setFramePtrSpillOffset(MFI->getObjectOffset(FramePtrSpillFI) +
                                NumBytes);
  AFI->setGPRCalleeSavedArea1Offset(GPRCS1Offset);
  AFI->setGPRCalleeSavedArea2Offset(GPRCS2Offset);
  AFI->setDPRCalleeSavedAreaOffset(DPRCSOffset);
  NumBytes = DPRCSOffset;

  int FramePtrOffsetInBlock = 0;
  unsigned adjustedGPRCS1Size = GPRCS1Size;
  if (tryFoldSPUpdateIntoPushPop(STI, MF, std::prev(MBBI), NumBytes)) {
    FramePtrOffsetInBlock = NumBytes;
    adjustedGPRCS1Size += NumBytes;
    NumBytes = 0;
  }

  if (adjustedGPRCS1Size) {
    CFAOffset -= adjustedGPRCS1Size;
    unsigned CFIIndex = MMI.addFrameInst(
        MCCFIInstruction::createDefCfaOffset(nullptr, CFAOffset));
    BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
        .addCFIIndex(CFIIndex)
        .setMIFlags(MachineInstr::FrameSetup);
  }
  for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(),
         E = CSI.end(); I != E; ++I) {
    unsigned Reg = I->getReg();
    int FI = I->getFrameIdx();
    switch (Reg) {
    case ARM::R8:
    case ARM::R9:
    case ARM::R10:
    case ARM::R11:
    case ARM::R12:
      if (STI.isTargetMachO())
        break;
      // fallthough
    case ARM::R0:
    case ARM::R1:
    case ARM::R2:
    case ARM::R3:
    case ARM::R4:
    case ARM::R5:
    case ARM::R6:
    case ARM::R7:
    case ARM::LR:
      unsigned CFIIndex = MMI.addFrameInst(MCCFIInstruction::createOffset(
          nullptr, MRI->getDwarfRegNum(Reg, true), MFI->getObjectOffset(FI)));
      BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
          .addCFIIndex(CFIIndex)
          .setMIFlags(MachineInstr::FrameSetup);
      break;
    }
  }

  // Adjust FP so it point to the stack slot that contains the previous FP.
  if (HasFP) {
    FramePtrOffsetInBlock +=
        MFI->getObjectOffset(FramePtrSpillFI) + GPRCS1Size + ArgRegsSaveSize;
    AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tADDrSPi), FramePtr)
      .addReg(ARM::SP).addImm(FramePtrOffsetInBlock / 4)
      .setMIFlags(MachineInstr::FrameSetup));
    if(FramePtrOffsetInBlock) {
      CFAOffset += FramePtrOffsetInBlock;
      unsigned CFIIndex = MMI.addFrameInst(MCCFIInstruction::createDefCfa(
          nullptr, MRI->getDwarfRegNum(FramePtr, true), CFAOffset));
      BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
          .addCFIIndex(CFIIndex)
          .setMIFlags(MachineInstr::FrameSetup);
    } else {
      unsigned CFIIndex =
          MMI.addFrameInst(MCCFIInstruction::createDefCfaRegister(
              nullptr, MRI->getDwarfRegNum(FramePtr, true)));
      BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
          .addCFIIndex(CFIIndex)
          .setMIFlags(MachineInstr::FrameSetup);
    }
    if (NumBytes > 508)
      // If offset is > 508 then sp cannot be adjusted in a single instruction,
      // try restoring from fp instead.
      AFI->setShouldRestoreSPFromFP(true);
  }

  if (NumBytes) {
    // Insert it after all the callee-save spills.
    emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -NumBytes,
                 MachineInstr::FrameSetup);
    if (!HasFP) {
      CFAOffset -= NumBytes;
      unsigned CFIIndex = MMI.addFrameInst(
          MCCFIInstruction::createDefCfaOffset(nullptr, CFAOffset));
      BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
          .addCFIIndex(CFIIndex)
          .setMIFlags(MachineInstr::FrameSetup);
    }
  }

  if (STI.isTargetELF() && HasFP)
    MFI->setOffsetAdjustment(MFI->getOffsetAdjustment() -
                             AFI->getFramePtrSpillOffset());

  AFI->setGPRCalleeSavedArea1Size(GPRCS1Size);
  AFI->setGPRCalleeSavedArea2Size(GPRCS2Size);
  AFI->setDPRCalleeSavedAreaSize(DPRCSSize);

  // Thumb1 does not currently support dynamic stack realignment.  Report a
  // fatal error rather then silently generate bad code.
  if (RegInfo->needsStackRealignment(MF))
      report_fatal_error("Dynamic stack realignment not supported for thumb1.");

  // If we need a base pointer, set it up here. It's whatever the value
  // of the stack pointer is at this point. Any variable size objects
  // will be allocated after this, so we can still use the base pointer
  // to reference locals.
  if (RegInfo->hasBasePointer(MF))
    AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr), BasePtr)
                   .addReg(ARM::SP));

  // If the frame has variable sized objects then the epilogue must restore
  // the sp from fp. We can assume there's an FP here since hasFP already
  // checks for hasVarSizedObjects.
  if (MFI->hasVarSizedObjects())
    AFI->setShouldRestoreSPFromFP(true);
}
Ejemplo n.º 6
0
/// getFrameIndexOffset - Returns the displacement from the frame register to
/// the stack frame of the specified index. This is the default implementation
/// which is likely incorrect for the target.
int TargetRegisterInfo::getFrameIndexOffset(MachineFunction &MF, int FI) const {
  const TargetFrameInfo &TFI = *MF.getTarget().getFrameInfo();
  MachineFrameInfo *MFI = MF.getFrameInfo();
  return MFI->getObjectOffset(FI) + MFI->getStackSize() -
    TFI.getOffsetOfLocalArea() + MFI->getOffsetAdjustment();
}
Ejemplo n.º 7
0
void Thumb1FrameLowering::emitPrologue(MachineFunction &MF) const {
  MachineBasicBlock &MBB = MF.front();
  MachineBasicBlock::iterator MBBI = MBB.begin();
  MachineFrameInfo  *MFI = MF.getFrameInfo();
  ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
  const Thumb1RegisterInfo *RegInfo =
    static_cast<const Thumb1RegisterInfo*>(MF.getTarget().getRegisterInfo());
  const Thumb1InstrInfo &TII =
    *static_cast<const Thumb1InstrInfo*>(MF.getTarget().getInstrInfo());

  unsigned VARegSaveSize = AFI->getVarArgsRegSaveSize();
  unsigned NumBytes = MFI->getStackSize();
  const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
  DebugLoc dl = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
  unsigned FramePtr = RegInfo->getFrameRegister(MF);
  unsigned BasePtr = RegInfo->getBaseRegister();

  // Thumb add/sub sp, imm8 instructions implicitly multiply the offset by 4.
  NumBytes = (NumBytes + 3) & ~3;
  MFI->setStackSize(NumBytes);

  // Determine the sizes of each callee-save spill areas and record which frame
  // belongs to which callee-save spill areas.
  unsigned GPRCS1Size = 0, GPRCS2Size = 0, DPRCSSize = 0;
  int FramePtrSpillFI = 0;

  if (VARegSaveSize)
    emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -VARegSaveSize,
                 MachineInstr::FrameSetup);

  if (!AFI->hasStackFrame()) {
    if (NumBytes != 0)
      emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -NumBytes,
                   MachineInstr::FrameSetup);
    return;
  }

  for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
    unsigned Reg = CSI[i].getReg();
    int FI = CSI[i].getFrameIdx();
    switch (Reg) {
    case ARM::R4:
    case ARM::R5:
    case ARM::R6:
    case ARM::R7:
    case ARM::LR:
      if (Reg == FramePtr)
        FramePtrSpillFI = FI;
      AFI->addGPRCalleeSavedArea1Frame(FI);
      GPRCS1Size += 4;
      break;
    case ARM::R8:
    case ARM::R9:
    case ARM::R10:
    case ARM::R11:
      if (Reg == FramePtr)
        FramePtrSpillFI = FI;
      if (STI.isTargetDarwin()) {
        AFI->addGPRCalleeSavedArea2Frame(FI);
        GPRCS2Size += 4;
      } else {
        AFI->addGPRCalleeSavedArea1Frame(FI);
        GPRCS1Size += 4;
      }
      break;
    default:
      AFI->addDPRCalleeSavedAreaFrame(FI);
      DPRCSSize += 8;
    }
  }

  if (MBBI != MBB.end() && MBBI->getOpcode() == ARM::tPUSH) {
    ++MBBI;
    if (MBBI != MBB.end())
      dl = MBBI->getDebugLoc();
  }

  // Determine starting offsets of spill areas.
  unsigned DPRCSOffset  = NumBytes - (GPRCS1Size + GPRCS2Size + DPRCSSize);
  unsigned GPRCS2Offset = DPRCSOffset + DPRCSSize;
  unsigned GPRCS1Offset = GPRCS2Offset + GPRCS2Size;
  AFI->setFramePtrSpillOffset(MFI->getObjectOffset(FramePtrSpillFI) + NumBytes);
  AFI->setGPRCalleeSavedArea1Offset(GPRCS1Offset);
  AFI->setGPRCalleeSavedArea2Offset(GPRCS2Offset);
  AFI->setDPRCalleeSavedAreaOffset(DPRCSOffset);
  NumBytes = DPRCSOffset;

  // Adjust FP so it point to the stack slot that contains the previous FP.
  if (hasFP(MF)) {
    AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tADDrSPi), FramePtr)
      .addFrameIndex(FramePtrSpillFI).addImm(0)
      .setMIFlags(MachineInstr::FrameSetup));
    if (NumBytes > 508)
      // If offset is > 508 then sp cannot be adjusted in a single instruction,
      // try restoring from fp instead.
      AFI->setShouldRestoreSPFromFP(true);
  }

  if (NumBytes)
    // Insert it after all the callee-save spills.
    emitSPUpdate(MBB, MBBI, TII, dl, *RegInfo, -NumBytes,
                 MachineInstr::FrameSetup);

  if (STI.isTargetELF() && hasFP(MF))
    MFI->setOffsetAdjustment(MFI->getOffsetAdjustment() -
                             AFI->getFramePtrSpillOffset());

  AFI->setGPRCalleeSavedArea1Size(GPRCS1Size);
  AFI->setGPRCalleeSavedArea2Size(GPRCS2Size);
  AFI->setDPRCalleeSavedAreaSize(DPRCSSize);

  // If we need a base pointer, set it up here. It's whatever the value
  // of the stack pointer is at this point. Any variable size objects
  // will be allocated after this, so we can still use the base pointer
  // to reference locals.
  if (RegInfo->hasBasePointer(MF))
    AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr), BasePtr)
                   .addReg(ARM::SP));

  // If the frame has variable sized objects then the epilogue must restore
  // the sp from fp. We can assume there's an FP here since hasFP already
  // checks for hasVarSizedObjects.
  if (MFI->hasVarSizedObjects())
    AFI->setShouldRestoreSPFromFP(true);
}
void ARMFrameLowering::emitPrologue(MachineFunction &MF) const {
  MachineBasicBlock &MBB = MF.front();
  MachineBasicBlock::iterator MBBI = MBB.begin();
  MachineFrameInfo  *MFI = MF.getFrameInfo();
  ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
  const ARMBaseRegisterInfo *RegInfo =
    static_cast<const ARMBaseRegisterInfo*>(MF.getTarget().getRegisterInfo());
  const ARMBaseInstrInfo &TII =
    *static_cast<const ARMBaseInstrInfo*>(MF.getTarget().getInstrInfo());
  assert(!AFI->isThumb1OnlyFunction() &&
         "This emitPrologue does not support Thumb1!");
  bool isARM = !AFI->isThumbFunction();
  unsigned VARegSaveSize = AFI->getVarArgsRegSaveSize();
  unsigned NumBytes = MFI->getStackSize();
  const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
  DebugLoc dl = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
  unsigned FramePtr = RegInfo->getFrameRegister(MF);

  // Determine the sizes of each callee-save spill areas and record which frame
  // belongs to which callee-save spill areas.
  unsigned GPRCS1Size = 0, GPRCS2Size = 0, DPRCSSize = 0;
  int FramePtrSpillFI = 0;

  // Allocate the vararg register save area. This is not counted in NumBytes.
  if (VARegSaveSize)
    emitSPUpdate(isARM, MBB, MBBI, dl, TII, -VARegSaveSize,
                 MachineInstr::FrameSetup);

  if (!AFI->hasStackFrame()) {
    if (NumBytes != 0)
      emitSPUpdate(isARM, MBB, MBBI, dl, TII, -NumBytes,
                   MachineInstr::FrameSetup);
    return;
  }

  for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
    unsigned Reg = CSI[i].getReg();
    int FI = CSI[i].getFrameIdx();
    switch (Reg) {
    case ARM::R4:
    case ARM::R5:
    case ARM::R6:
    case ARM::R7:
    case ARM::LR:
      if (Reg == FramePtr)
        FramePtrSpillFI = FI;
      AFI->addGPRCalleeSavedArea1Frame(FI);
      GPRCS1Size += 4;
      break;
    case ARM::R8:
    case ARM::R9:
    case ARM::R10:
    case ARM::R11:
      if (Reg == FramePtr)
        FramePtrSpillFI = FI;
      if (STI.isTargetDarwin()) {
        AFI->addGPRCalleeSavedArea2Frame(FI);
        GPRCS2Size += 4;
      } else {
        AFI->addGPRCalleeSavedArea1Frame(FI);
        GPRCS1Size += 4;
      }
      break;
    default:
      AFI->addDPRCalleeSavedAreaFrame(FI);
      DPRCSSize += 8;
    }
  }

  // Move past area 1.
  if (GPRCS1Size > 0) MBBI++;

  // Set FP to point to the stack slot that contains the previous FP.
  // For Darwin, FP is R7, which has now been stored in spill area 1.
  // Otherwise, if this is not Darwin, all the callee-saved registers go
  // into spill area 1, including the FP in R11.  In either case, it is
  // now safe to emit this assignment.
  bool HasFP = hasFP(MF);
  if (HasFP) {
    unsigned ADDriOpc = !AFI->isThumbFunction() ? ARM::ADDri : ARM::t2ADDri;
    MachineInstrBuilder MIB =
      BuildMI(MBB, MBBI, dl, TII.get(ADDriOpc), FramePtr)
      .addFrameIndex(FramePtrSpillFI).addImm(0)
      .setMIFlag(MachineInstr::FrameSetup);
    AddDefaultCC(AddDefaultPred(MIB));
  }

  // Move past area 2.
  if (GPRCS2Size > 0) MBBI++;

  // Determine starting offsets of spill areas.
  unsigned DPRCSOffset  = NumBytes - (GPRCS1Size + GPRCS2Size + DPRCSSize);
  unsigned GPRCS2Offset = DPRCSOffset + DPRCSSize;
  unsigned GPRCS1Offset = GPRCS2Offset + GPRCS2Size;
  if (HasFP)
    AFI->setFramePtrSpillOffset(MFI->getObjectOffset(FramePtrSpillFI) +
                                NumBytes);
  AFI->setGPRCalleeSavedArea1Offset(GPRCS1Offset);
  AFI->setGPRCalleeSavedArea2Offset(GPRCS2Offset);
  AFI->setDPRCalleeSavedAreaOffset(DPRCSOffset);

  // Move past area 3.
  if (DPRCSSize > 0) {
    MBBI++;
    // Since vpush register list cannot have gaps, there may be multiple vpush
    // instructions in the prologue.
    while (MBBI->getOpcode() == ARM::VSTMDDB_UPD)
      MBBI++;
  }

  NumBytes = DPRCSOffset;
  if (NumBytes) {
    // Adjust SP after all the callee-save spills.
    emitSPUpdate(isARM, MBB, MBBI, dl, TII, -NumBytes,
                 MachineInstr::FrameSetup);
    if (HasFP && isARM)
      // Restore from fp only in ARM mode: e.g. sub sp, r7, #24
      // Note it's not safe to do this in Thumb2 mode because it would have
      // taken two instructions:
      // mov sp, r7
      // sub sp, #24
      // If an interrupt is taken between the two instructions, then sp is in
      // an inconsistent state (pointing to the middle of callee-saved area).
      // The interrupt handler can end up clobbering the registers.
      AFI->setShouldRestoreSPFromFP(true);
  }

  if (STI.isTargetELF() && hasFP(MF))
    MFI->setOffsetAdjustment(MFI->getOffsetAdjustment() -
                             AFI->getFramePtrSpillOffset());

  AFI->setGPRCalleeSavedArea1Size(GPRCS1Size);
  AFI->setGPRCalleeSavedArea2Size(GPRCS2Size);
  AFI->setDPRCalleeSavedAreaSize(DPRCSSize);

  // If we need dynamic stack realignment, do it here. Be paranoid and make
  // sure if we also have VLAs, we have a base pointer for frame access.
  if (RegInfo->needsStackRealignment(MF)) {
    unsigned MaxAlign = MFI->getMaxAlignment();
    assert (!AFI->isThumb1OnlyFunction());
    if (!AFI->isThumbFunction()) {
      // Emit bic sp, sp, MaxAlign
      AddDefaultCC(AddDefaultPred(BuildMI(MBB, MBBI, dl,
                                          TII.get(ARM::BICri), ARM::SP)
                                  .addReg(ARM::SP, RegState::Kill)
                                  .addImm(MaxAlign-1)));
    } else {
      // We cannot use sp as source/dest register here, thus we're emitting the
      // following sequence:
      // mov r4, sp
      // bic r4, r4, MaxAlign
      // mov sp, r4
      // FIXME: It will be better just to find spare register here.
      AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr), ARM::R4)
        .addReg(ARM::SP, RegState::Kill));
      AddDefaultCC(AddDefaultPred(BuildMI(MBB, MBBI, dl,
                                          TII.get(ARM::t2BICri), ARM::R4)
                                  .addReg(ARM::R4, RegState::Kill)
                                  .addImm(MaxAlign-1)));
      AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr), ARM::SP)
        .addReg(ARM::R4, RegState::Kill));
    }

    AFI->setShouldRestoreSPFromFP(true);
  }

  // If we need a base pointer, set it up here. It's whatever the value
  // of the stack pointer is at this point. Any variable size objects
  // will be allocated after this, so we can still use the base pointer
  // to reference locals.
  // FIXME: Clarify FrameSetup flags here.
  if (RegInfo->hasBasePointer(MF)) {
    if (isARM)
      BuildMI(MBB, MBBI, dl,
              TII.get(ARM::MOVr), RegInfo->getBaseRegister())
        .addReg(ARM::SP)
        .addImm((unsigned)ARMCC::AL).addReg(0).addReg(0);
    else
      AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVr),
                             RegInfo->getBaseRegister())
        .addReg(ARM::SP));
  }

  // If the frame has variable sized objects then the epilogue must restore
  // the sp from fp. We can assume there's an FP here since hasFP already
  // checks for hasVarSizedObjects.
  if (MFI->hasVarSizedObjects())
    AFI->setShouldRestoreSPFromFP(true);
}
Ejemplo n.º 9
0
void Thumb1RegisterInfo::emitPrologue(MachineFunction &MF) const {
  MachineBasicBlock &MBB = MF.front();
  MachineBasicBlock::iterator MBBI = MBB.begin();
  MachineFrameInfo  *MFI = MF.getFrameInfo();
  ARMFunctionInfo *AFI = MF.getInfo<ARMFunctionInfo>();
  unsigned VARegSaveSize = AFI->getVarArgsRegSaveSize();
  unsigned NumBytes = MFI->getStackSize();
  const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo();
  DebugLoc dl = (MBBI != MBB.end() ?
                 MBBI->getDebugLoc() : DebugLoc::getUnknownLoc());

  // Thumb add/sub sp, imm8 instructions implicitly multiply the offset by 4.
  NumBytes = (NumBytes + 3) & ~3;
  MFI->setStackSize(NumBytes);

  // Determine the sizes of each callee-save spill areas and record which frame
  // belongs to which callee-save spill areas.
  unsigned GPRCS1Size = 0, GPRCS2Size = 0, DPRCSSize = 0;
  int FramePtrSpillFI = 0;

  if (VARegSaveSize)
    emitSPUpdate(MBB, MBBI, TII, dl, *this, -VARegSaveSize);

  if (!AFI->hasStackFrame()) {
    if (NumBytes != 0)
      emitSPUpdate(MBB, MBBI, TII, dl, *this, -NumBytes);
    return;
  }

  for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
    unsigned Reg = CSI[i].getReg();
    int FI = CSI[i].getFrameIdx();
    switch (Reg) {
    case ARM::R4:
    case ARM::R5:
    case ARM::R6:
    case ARM::R7:
    case ARM::LR:
      if (Reg == FramePtr)
        FramePtrSpillFI = FI;
      AFI->addGPRCalleeSavedArea1Frame(FI);
      GPRCS1Size += 4;
      break;
    case ARM::R8:
    case ARM::R9:
    case ARM::R10:
    case ARM::R11:
      if (Reg == FramePtr)
        FramePtrSpillFI = FI;
      if (STI.isTargetDarwin()) {
        AFI->addGPRCalleeSavedArea2Frame(FI);
        GPRCS2Size += 4;
      } else {
        AFI->addGPRCalleeSavedArea1Frame(FI);
        GPRCS1Size += 4;
      }
      break;
    default:
      AFI->addDPRCalleeSavedAreaFrame(FI);
      DPRCSSize += 8;
    }
  }

  if (MBBI != MBB.end() && MBBI->getOpcode() == ARM::tPUSH) {
    ++MBBI;
    if (MBBI != MBB.end())
      dl = MBBI->getDebugLoc();
  }

  // Darwin ABI requires FP to point to the stack slot that contains the
  // previous FP.
  if (STI.isTargetDarwin() || hasFP(MF)) {
    BuildMI(MBB, MBBI, dl, TII.get(ARM::tADDrSPi), FramePtr)
      .addFrameIndex(FramePtrSpillFI).addImm(0);
  }

  // Determine starting offsets of spill areas.
  unsigned DPRCSOffset  = NumBytes - (GPRCS1Size + GPRCS2Size + DPRCSSize);
  unsigned GPRCS2Offset = DPRCSOffset + DPRCSSize;
  unsigned GPRCS1Offset = GPRCS2Offset + GPRCS2Size;
  AFI->setFramePtrSpillOffset(MFI->getObjectOffset(FramePtrSpillFI) + NumBytes);
  AFI->setGPRCalleeSavedArea1Offset(GPRCS1Offset);
  AFI->setGPRCalleeSavedArea2Offset(GPRCS2Offset);
  AFI->setDPRCalleeSavedAreaOffset(DPRCSOffset);

  NumBytes = DPRCSOffset;
  if (NumBytes) {
    // Insert it after all the callee-save spills.
    emitSPUpdate(MBB, MBBI, TII, dl, *this, -NumBytes);
  }

  if (STI.isTargetELF() && hasFP(MF)) {
    MFI->setOffsetAdjustment(MFI->getOffsetAdjustment() -
                             AFI->getFramePtrSpillOffset());
  }

  AFI->setGPRCalleeSavedArea1Size(GPRCS1Size);
  AFI->setGPRCalleeSavedArea2Size(GPRCS2Size);
  AFI->setDPRCalleeSavedAreaSize(DPRCSSize);
}
Ejemplo n.º 10
0
void SVMRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
                                          int SPAdj, RegScavenger *RS) const
{
    assert(SPAdj == 0 && "Not allowed to modify SP");

    unsigned i = 0;
    MachineInstr &MI = *II;
    while (!MI.getOperand(i).isFI()) {
        ++i;
        assert(i < MI.getNumOperands() && "Instr doesn't have FrameIndex operand!");
    }

    int FrameIndex = MI.getOperand(i).getIndex();
    DebugLoc dl = MI.getDebugLoc();
    MachineBasicBlock &MBB = *MI.getParent();
    MachineFunction &MF = *MI.getParent()->getParent();
    MachineFrameInfo *MFI = MF.getFrameInfo();

    int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex);
    assert(MFI->getOffsetAdjustment() == 0);

    if (Offset < 0) {
        /*
         * Negative offsets are special; they represent offsets into the
         * caller's stack frame. We can calculate that offset now that we
         * know the final stack frame size of the current function.
         *
         * We need to reach upward, past this function's stack frame, and
         * past the SVM CallFrame, into the bottom of the caller's frame.
         */

        const int CallFrameSize = 8 * sizeof(uint32_t);

        Offset = -Offset - 1;
        Offset += MFI->getStackSize();
        Offset += CallFrameSize;
    }

    // Extract offsets from instructions that have immediate offsets too
    switch (MI.getOpcode()) {
    case SVM::LDRsp:
    case SVM::STRsp:
        Offset += MI.getOperand(i+1).getImm();
        MI.getOperand(i+1).ChangeToImmediate(0);
        break;
    }

    int Remaining = Offset;

    if (MI.isDebugValue()) {
        MI.getOperand(i).ChangeToImmediate(Offset);
        return;
    }

    // Encode as much offset as possible into the original instruction.
    switch (MI.getOpcode()) {

        // Encodings with an 8-bit unsigned word offset.
        // Supports multiples of four, from 0 to 1020.
    case SVM::LDRsp:
    case SVM::STRsp:
    case SVM::ADDsp: {
        unsigned Imm = std::min(Remaining & ~3, 1020);
        MI.getOperand(i).ChangeToImmediate(Imm);
        Remaining -= Imm;
        break;
    }
    
    default:
        assert(0 && "Unsupported instruction in eliminateFrameIndex()");
    }

    // If there's a residual, rewrite the instruction further.
    if (Remaining == 0)
        return;

    switch (MI.getOpcode()) {

        // ADDsp: Put in additional ADD instructions afterward, to cover
        // the residual offset. Doesn't require any additional registers.
    case SVM::ADDsp:
        do {
            unsigned Imm = std::min(Remaining, 0xFF);
            II++;
            BuildMI(MBB, II, dl, TII.get(SVM::ADDSi8))
                .addReg(MI.getOperand(0).getReg())
                .addReg(MI.getOperand(0).getReg())
                .addImm(Imm);
            II--;
            Remaining -= Imm;
        } while (Remaining != 0);
        break;

        // Large stack load/stores -> addrops. For correctness, we need
        // to be able to do spills to large stack frames without corrupting
        // state like r8-r9 or using any additional registers. So, we use
        // this slow addrop to do all the work.
    case SVM::STRsp:
        rewriteLongStackOp(II, 0xc4000000, Offset, SVM::STRspi);
        break;
    case SVM::LDRsp:
        rewriteLongStackOp(II, 0xc5000000, Offset, SVM::LDRspi);
        break;

    default:
        assert(0 && "Unsupported SP offset in eliminateFrameIndex()");
    }
}