-
-void MSP430RegisterInfo::emitPrologue(MachineFunction &MF) const {
- MachineBasicBlock &MBB = MF.front(); // Prolog goes in entry BB
- MachineFrameInfo *MFI = MF.getFrameInfo();
- MSP430MachineFunctionInfo *MSP430FI = MF.getInfo<MSP430MachineFunctionInfo>();
- MachineBasicBlock::iterator MBBI = MBB.begin();
- DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
-
- // Get the number of bytes to allocate from the FrameInfo.
- uint64_t StackSize = MFI->getStackSize();
-
- uint64_t NumBytes = 0;
- if (hasFP(MF)) {
- // Calculate required stack adjustment
- uint64_t FrameSize = StackSize - 2;
- NumBytes = FrameSize - MSP430FI->getCalleeSavedFrameSize();
-
- // Get the offset of the stack slot for the EBP register... which is
- // guaranteed to be the last slot by processFunctionBeforeFrameFinalized.
- // Update the frame offset adjustment.
- MFI->setOffsetAdjustment(-NumBytes);
-
- // Save FPW into the appropriate stack slot...
- BuildMI(MBB, MBBI, DL, TII.get(MSP430::PUSH16r))
- .addReg(MSP430::FPW, RegState::Kill);
-
- // Update FPW with the new base value...
- BuildMI(MBB, MBBI, DL, TII.get(MSP430::MOV16rr), MSP430::FPW)
- .addReg(MSP430::SPW);
-
- // Mark the FramePtr as live-in in every block except the entry.
- for (MachineFunction::iterator I = llvm::next(MF.begin()), E = MF.end();
- I != E; ++I)
- I->addLiveIn(MSP430::FPW);
-
- } else
- NumBytes = StackSize - MSP430FI->getCalleeSavedFrameSize();
-
- // Skip the callee-saved push instructions.
- while (MBBI != MBB.end() && (MBBI->getOpcode() == MSP430::PUSH16r))
- ++MBBI;
-
- if (MBBI != MBB.end())
- DL = MBBI->getDebugLoc();
-
- if (NumBytes) { // adjust stack pointer: SPW -= numbytes
- // If there is an SUB16ri of SPW immediately before this instruction, merge
- // the two.
- //NumBytes -= mergeSPUpdates(MBB, MBBI, true);
- // If there is an ADD16ri or SUB16ri of SPW immediately after this
- // instruction, merge the two instructions.
- // mergeSPUpdatesDown(MBB, MBBI, &NumBytes);
-
- if (NumBytes) {
- MachineInstr *MI =
- BuildMI(MBB, MBBI, DL, TII.get(MSP430::SUB16ri), MSP430::SPW)
- .addReg(MSP430::SPW).addImm(NumBytes);
- // The SRW implicit def is dead.
- MI->getOperand(3).setIsDead();
- }
- }
-}
-
-void MSP430RegisterInfo::emitEpilogue(MachineFunction &MF,
- MachineBasicBlock &MBB) const {
- const MachineFrameInfo *MFI = MF.getFrameInfo();
- MSP430MachineFunctionInfo *MSP430FI = MF.getInfo<MSP430MachineFunctionInfo>();
- MachineBasicBlock::iterator MBBI = prior(MBB.end());
- unsigned RetOpcode = MBBI->getOpcode();
- DebugLoc DL = MBBI->getDebugLoc();
-
- switch (RetOpcode) {
- case MSP430::RET:
- case MSP430::RETI: break; // These are ok
- default:
- llvm_unreachable("Can only insert epilog into returning blocks");
- }
-
- // Get the number of bytes to allocate from the FrameInfo
- uint64_t StackSize = MFI->getStackSize();
- unsigned CSSize = MSP430FI->getCalleeSavedFrameSize();
- uint64_t NumBytes = 0;
-
- if (hasFP(MF)) {
- // Calculate required stack adjustment
- uint64_t FrameSize = StackSize - 2;
- NumBytes = FrameSize - CSSize;
-
- // pop FPW.
- BuildMI(MBB, MBBI, DL, TII.get(MSP430::POP16r), MSP430::FPW);
- } else
- NumBytes = StackSize - CSSize;
-
- // Skip the callee-saved pop instructions.
- while (MBBI != MBB.begin()) {
- MachineBasicBlock::iterator PI = prior(MBBI);
- unsigned Opc = PI->getOpcode();
- if (Opc != MSP430::POP16r && !PI->getDesc().isTerminator())
- break;
- --MBBI;
- }
-
- DL = MBBI->getDebugLoc();
-
- // If there is an ADD16ri or SUB16ri of SPW immediately before this
- // instruction, merge the two instructions.
- //if (NumBytes || MFI->hasVarSizedObjects())
- // mergeSPUpdatesUp(MBB, MBBI, StackPtr, &NumBytes);
-
- if (MFI->hasVarSizedObjects()) {
- BuildMI(MBB, MBBI, DL,
- TII.get(MSP430::MOV16rr), MSP430::SPW).addReg(MSP430::FPW);
- if (CSSize) {
- MachineInstr *MI =
- BuildMI(MBB, MBBI, DL,
- TII.get(MSP430::SUB16ri), MSP430::SPW)
- .addReg(MSP430::SPW).addImm(CSSize);
- // The SRW implicit def is dead.
- MI->getOperand(3).setIsDead();
- }
- } else {
- // adjust stack pointer back: SPW += numbytes
- if (NumBytes) {
- MachineInstr *MI =
- BuildMI(MBB, MBBI, DL, TII.get(MSP430::ADD16ri), MSP430::SPW)
- .addReg(MSP430::SPW).addImm(NumBytes);
- // The SRW implicit def is dead.
- MI->getOperand(3).setIsDead();
- }
- }
-}
-
-unsigned MSP430RegisterInfo::getRARegister() const {
- return MSP430::PCW;
-}
-