#define DEBUG_TYPE "msp430-reg-info"
#include "MSP430.h"
+#include "MSP430MachineFunctionInfo.h"
#include "MSP430RegisterInfo.h"
+#include "MSP430TargetMachine.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/ADT/BitVector.h"
+#include "llvm/Support/ErrorHandling.h"
using namespace llvm;
// FIXME: Provide proper call frame setup / destroy opcodes.
-MSP430RegisterInfo::MSP430RegisterInfo(const TargetInstrInfo &tii)
- : MSP430GenRegisterInfo(MSP430::NOP, MSP430::NOP),
- TII(tii) {}
+MSP430RegisterInfo::MSP430RegisterInfo(MSP430TargetMachine &tm,
+ const TargetInstrInfo &tii)
+ : MSP430GenRegisterInfo(MSP430::ADJCALLSTACKDOWN, MSP430::ADJCALLSTACKUP),
+ TM(tm), TII(tii) {
+ StackAlign = TM.getFrameInfo()->getStackAlignment();
+}
const unsigned*
MSP430RegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) const {
- assert(0 && "Not implemented yet!");
+ static const unsigned CalleeSavedRegs[] = {
+ MSP430::FPW, MSP430::R5W, MSP430::R6W, MSP430::R7W,
+ MSP430::R8W, MSP430::R9W, MSP430::R10W, MSP430::R11W,
+ 0
+ };
+
+ return CalleeSavedRegs;
}
-const TargetRegisterClass* const*
+const TargetRegisterClass *const *
MSP430RegisterInfo::getCalleeSavedRegClasses(const MachineFunction *MF) const {
- assert(0 && "Not implemented yet!");
+ static const TargetRegisterClass * const CalleeSavedRegClasses[] = {
+ &MSP430::GR16RegClass, &MSP430::GR16RegClass,
+ &MSP430::GR16RegClass, &MSP430::GR16RegClass,
+ &MSP430::GR16RegClass, &MSP430::GR16RegClass,
+ &MSP430::GR16RegClass, &MSP430::GR16RegClass,
+ 0
+ };
+
+ return CalleeSavedRegClasses;
}
-BitVector
-MSP430RegisterInfo::getReservedRegs(const MachineFunction &MF) const {
+BitVector MSP430RegisterInfo::getReservedRegs(const MachineFunction &MF) const {
BitVector Reserved(getNumRegs());
// Mark 4 special registers as reserved.
- Reserved.set(MSP430::PC);
- Reserved.set(MSP430::SP);
- Reserved.set(MSP430::SR);
- Reserved.set(MSP430::CG);
+ Reserved.set(MSP430::PCW);
+ Reserved.set(MSP430::SPW);
+ Reserved.set(MSP430::SRW);
+ Reserved.set(MSP430::CGW);
// Mark frame pointer as reserved if needed.
if (hasFP(MF))
- Reserved.set(MSP430::FP);
+ Reserved.set(MSP430::FPW);
return Reserved;
}
+const TargetRegisterClass *
+MSP430RegisterInfo::getPointerRegClass(unsigned Kind) const {
+ return &MSP430::GR16RegClass;
+}
+
+
bool MSP430RegisterInfo::hasFP(const MachineFunction &MF) const {
return NoFramePointerElim || MF.getFrameInfo()->hasVarSizedObjects();
}
-void
+bool MSP430RegisterInfo::hasReservedCallFrame(MachineFunction &MF) const {
+ return !MF.getFrameInfo()->hasVarSizedObjects();
+}
+
+void MSP430RegisterInfo::
+eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator I) const {
+ if (!hasReservedCallFrame(MF)) {
+ // If the stack pointer can be changed after prologue, turn the
+ // adjcallstackup instruction into a 'sub SPW, <amt>' and the
+ // adjcallstackdown instruction into 'add SPW, <amt>'
+ // TODO: consider using push / pop instead of sub + store / add
+ MachineInstr *Old = I;
+ uint64_t Amount = Old->getOperand(0).getImm();
+ if (Amount != 0) {
+ // We need to keep the stack aligned properly. To do this, we round the
+ // amount of space needed for the outgoing arguments up to the next
+ // alignment boundary.
+ Amount = (Amount+StackAlign-1)/StackAlign*StackAlign;
+
+ MachineInstr *New = 0;
+ if (Old->getOpcode() == getCallFrameSetupOpcode()) {
+ New = BuildMI(MF, Old->getDebugLoc(),
+ TII.get(MSP430::SUB16ri), MSP430::SPW)
+ .addReg(MSP430::SPW).addImm(Amount);
+ } else {
+ assert(Old->getOpcode() == getCallFrameDestroyOpcode());
+ // factor out the amount the callee already popped.
+ uint64_t CalleeAmt = Old->getOperand(1).getImm();
+ Amount -= CalleeAmt;
+ if (Amount)
+ New = BuildMI(MF, Old->getDebugLoc(),
+ TII.get(MSP430::ADD16ri), MSP430::SPW)
+ .addReg(MSP430::SPW).addImm(Amount);
+ }
+
+ if (New) {
+ // The SRW implicit def is dead.
+ New->getOperand(3).setIsDead();
+
+ // Replace the pseudo instruction with a new instruction...
+ MBB.insert(I, New);
+ }
+ }
+ } else if (I->getOpcode() == getCallFrameDestroyOpcode()) {
+ // If we are performing frame pointer elimination and if the callee pops
+ // something off the stack pointer, add it back.
+ if (uint64_t CalleeAmt = I->getOperand(1).getImm()) {
+ MachineInstr *Old = I;
+ MachineInstr *New =
+ BuildMI(MF, Old->getDebugLoc(), TII.get(MSP430::SUB16ri),
+ MSP430::SPW).addReg(MSP430::SPW).addImm(CalleeAmt);
+ // The SRW implicit def is dead.
+ New->getOperand(3).setIsDead();
+
+ MBB.insert(I, New);
+ }
+ }
+
+ MBB.erase(I);
+}
+
+unsigned
MSP430RegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II,
- int SPAdj, RegScavenger *RS) const {
- assert(0 && "Not implemented yet!");
+ int SPAdj, int *Value,
+ RegScavenger *RS) const {
+ assert(SPAdj == 0 && "Unexpected");
+
+ unsigned i = 0;
+ MachineInstr &MI = *II;
+ MachineBasicBlock &MBB = *MI.getParent();
+ MachineFunction &MF = *MBB.getParent();
+ DebugLoc dl = MI.getDebugLoc();
+ while (!MI.getOperand(i).isFI()) {
+ ++i;
+ assert(i < MI.getNumOperands() && "Instr doesn't have FrameIndex operand!");
+ }
+
+ int FrameIndex = MI.getOperand(i).getIndex();
+
+ unsigned BasePtr = (hasFP(MF) ? MSP430::FPW : MSP430::SPW);
+ int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex);
+
+ // Skip the saved PC
+ Offset += 2;
+
+ if (!hasFP(MF))
+ Offset += MF.getFrameInfo()->getStackSize();
+ else
+ Offset += 2; // Skip the saved FPW
+
+ // Fold imm into offset
+ Offset += MI.getOperand(i+1).getImm();
+
+ if (MI.getOpcode() == MSP430::ADD16ri) {
+ // This is actually "load effective address" of the stack slot
+ // instruction. We have only two-address instructions, thus we need to
+ // expand it into mov + add
+
+ MI.setDesc(TII.get(MSP430::MOV16rr));
+ MI.getOperand(i).ChangeToRegister(BasePtr, false);
+
+ if (Offset == 0)
+ return 0;
+
+ // We need to materialize the offset via add instruction.
+ unsigned DstReg = MI.getOperand(0).getReg();
+ if (Offset < 0)
+ BuildMI(MBB, next(II), dl, TII.get(MSP430::SUB16ri), DstReg)
+ .addReg(DstReg).addImm(-Offset);
+ else
+ BuildMI(MBB, next(II), dl, TII.get(MSP430::ADD16ri), DstReg)
+ .addReg(DstReg).addImm(Offset);
+
+ return 0;
+ }
+
+ MI.getOperand(i).ChangeToRegister(BasePtr, false);
+ MI.getOperand(i+1).ChangeToImmediate(Offset);
+ return 0;
}
+void
+MSP430RegisterInfo::processFunctionBeforeFrameFinalized(MachineFunction &MF)
+ const {
+ // Create a frame entry for the FPW register that must be saved.
+ if (hasFP(MF)) {
+ int FrameIdx = MF.getFrameInfo()->CreateFixedObject(2, -4, true, false);
+ assert(FrameIdx == MF.getFrameInfo()->getObjectIndexBegin() &&
+ "Slot for FPW register must be last in order to be found!");
+ FrameIdx = 0;
+ }
+}
+
+
void MSP430RegisterInfo::emitPrologue(MachineFunction &MF) const {
- assert(0 && "Not implemented yet!");
+ 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::getUnknownLoc());
+
+ // 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 = 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 {
- assert(0 && "Not implemented yet!");
+ 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: 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 {
- assert(0 && "Not implemented yet!");
+ return MSP430::PCW;
}
-unsigned MSP430RegisterInfo::getFrameRegister(MachineFunction &MF) const {
- assert(0 && "Not implemented yet!");
+unsigned MSP430RegisterInfo::getFrameRegister(const MachineFunction &MF) const {
+ return hasFP(MF) ? MSP430::FPW : MSP430::SPW;
}
int MSP430RegisterInfo::getDwarfRegNum(unsigned RegNum, bool isEH) const {
- assert(0 && "Not implemented yet!");
+ llvm_unreachable("Not implemented yet!");
+ return 0;
}
#include "MSP430GenRegisterInfo.inc"