| //===- XCoreRegisterInfo.cpp - XCore Register Information -------*- C++ -*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file contains the XCore implementation of the MRegisterInfo class. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "XCoreRegisterInfo.h" |
| #include "XCoreMachineFunctionInfo.h" |
| #include "XCore.h" |
| #include "llvm/CodeGen/MachineInstrBuilder.h" |
| #include "llvm/CodeGen/MachineFunction.h" |
| #include "llvm/CodeGen/MachineFrameInfo.h" |
| #include "llvm/CodeGen/MachineModuleInfo.h" |
| #include "llvm/CodeGen/MachineRegisterInfo.h" |
| #include "llvm/CodeGen/RegisterScavenging.h" |
| #include "llvm/Target/TargetFrameLowering.h" |
| #include "llvm/Target/TargetMachine.h" |
| #include "llvm/Target/TargetOptions.h" |
| #include "llvm/Target/TargetInstrInfo.h" |
| #include "llvm/Type.h" |
| #include "llvm/Function.h" |
| #include "llvm/ADT/BitVector.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "llvm/Support/Debug.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/raw_ostream.h" |
| |
| #define GET_REGINFO_TARGET_DESC |
| #include "XCoreGenRegisterInfo.inc" |
| |
| using namespace llvm; |
| |
| XCoreRegisterInfo::XCoreRegisterInfo(const TargetInstrInfo &tii) |
| : XCoreGenRegisterInfo(XCore::LR), TII(tii) { |
| } |
| |
| // helper functions |
| static inline bool isImmUs(unsigned val) { |
| return val <= 11; |
| } |
| |
| static inline bool isImmU6(unsigned val) { |
| return val < (1 << 6); |
| } |
| |
| static inline bool isImmU16(unsigned val) { |
| return val < (1 << 16); |
| } |
| |
| static const unsigned XCore_ArgRegs[] = { |
| XCore::R0, XCore::R1, XCore::R2, XCore::R3 |
| }; |
| |
| const unsigned * XCoreRegisterInfo::getArgRegs(const MachineFunction *MF) |
| { |
| return XCore_ArgRegs; |
| } |
| |
| unsigned XCoreRegisterInfo::getNumArgRegs(const MachineFunction *MF) |
| { |
| return array_lengthof(XCore_ArgRegs); |
| } |
| |
| bool XCoreRegisterInfo::needsFrameMoves(const MachineFunction &MF) { |
| return MF.getMMI().hasDebugInfo() || |
| MF.getFunction()->needsUnwindTableEntry(); |
| } |
| |
| const unsigned* XCoreRegisterInfo::getCalleeSavedRegs(const MachineFunction *MF) |
| const { |
| static const unsigned CalleeSavedRegs[] = { |
| XCore::R4, XCore::R5, XCore::R6, XCore::R7, |
| XCore::R8, XCore::R9, XCore::R10, XCore::LR, |
| 0 |
| }; |
| return CalleeSavedRegs; |
| } |
| |
| BitVector XCoreRegisterInfo::getReservedRegs(const MachineFunction &MF) const { |
| BitVector Reserved(getNumRegs()); |
| const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering(); |
| |
| Reserved.set(XCore::CP); |
| Reserved.set(XCore::DP); |
| Reserved.set(XCore::SP); |
| Reserved.set(XCore::LR); |
| if (TFI->hasFP(MF)) { |
| Reserved.set(XCore::R10); |
| } |
| return Reserved; |
| } |
| |
| bool |
| XCoreRegisterInfo::requiresRegisterScavenging(const MachineFunction &MF) const { |
| const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering(); |
| |
| // TODO can we estimate stack size? |
| return TFI->hasFP(MF); |
| } |
| |
| bool |
| XCoreRegisterInfo::useFPForScavengingIndex(const MachineFunction &MF) const { |
| return false; |
| } |
| |
| // This function eliminates ADJCALLSTACKDOWN, |
| // ADJCALLSTACKUP pseudo instructions |
| void XCoreRegisterInfo:: |
| eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB, |
| MachineBasicBlock::iterator I) const { |
| const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering(); |
| |
| if (!TFI->hasReservedCallFrame(MF)) { |
| // Turn the adjcallstackdown instruction into 'extsp <amt>' and the |
| // adjcallstackup instruction into 'ldaw sp, sp[<amt>]' |
| 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. |
| unsigned Align = TFI->getStackAlignment(); |
| Amount = (Amount+Align-1)/Align*Align; |
| |
| assert(Amount%4 == 0); |
| Amount /= 4; |
| |
| bool isU6 = isImmU6(Amount); |
| if (!isU6 && !isImmU16(Amount)) { |
| // FIX could emit multiple instructions in this case. |
| #ifndef NDEBUG |
| errs() << "eliminateCallFramePseudoInstr size too big: " |
| << Amount << "\n"; |
| #endif |
| llvm_unreachable(0); |
| } |
| |
| MachineInstr *New; |
| if (Old->getOpcode() == XCore::ADJCALLSTACKDOWN) { |
| int Opcode = isU6 ? XCore::EXTSP_u6 : XCore::EXTSP_lu6; |
| New=BuildMI(MF, Old->getDebugLoc(), TII.get(Opcode)) |
| .addImm(Amount); |
| } else { |
| assert(Old->getOpcode() == XCore::ADJCALLSTACKUP); |
| int Opcode = isU6 ? XCore::LDAWSP_ru6_RRegs : XCore::LDAWSP_lru6_RRegs; |
| New=BuildMI(MF, Old->getDebugLoc(), TII.get(Opcode), XCore::SP) |
| .addImm(Amount); |
| } |
| |
| // Replace the pseudo instruction with a new instruction... |
| MBB.insert(I, New); |
| } |
| } |
| |
| MBB.erase(I); |
| } |
| |
| void |
| XCoreRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator II, |
| int SPAdj, RegScavenger *RS) const { |
| assert(SPAdj == 0 && "Unexpected"); |
| MachineInstr &MI = *II; |
| DebugLoc dl = MI.getDebugLoc(); |
| unsigned i = 0; |
| |
| while (!MI.getOperand(i).isFI()) { |
| ++i; |
| assert(i < MI.getNumOperands() && "Instr doesn't have FrameIndex operand!"); |
| } |
| |
| MachineOperand &FrameOp = MI.getOperand(i); |
| int FrameIndex = FrameOp.getIndex(); |
| |
| MachineFunction &MF = *MI.getParent()->getParent(); |
| const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering(); |
| int Offset = MF.getFrameInfo()->getObjectOffset(FrameIndex); |
| int StackSize = MF.getFrameInfo()->getStackSize(); |
| |
| #ifndef NDEBUG |
| DEBUG(errs() << "\nFunction : " |
| << MF.getFunction()->getName() << "\n"); |
| DEBUG(errs() << "<--------->\n"); |
| DEBUG(MI.print(errs())); |
| DEBUG(errs() << "FrameIndex : " << FrameIndex << "\n"); |
| DEBUG(errs() << "FrameOffset : " << Offset << "\n"); |
| DEBUG(errs() << "StackSize : " << StackSize << "\n"); |
| #endif |
| |
| Offset += StackSize; |
| |
| unsigned FrameReg = getFrameRegister(MF); |
| |
| // Special handling of DBG_VALUE instructions. |
| if (MI.isDebugValue()) { |
| MI.getOperand(i).ChangeToRegister(FrameReg, false /*isDef*/); |
| MI.getOperand(i+1).ChangeToImmediate(Offset); |
| return; |
| } |
| |
| // fold constant into offset. |
| Offset += MI.getOperand(i + 1).getImm(); |
| MI.getOperand(i + 1).ChangeToImmediate(0); |
| |
| assert(Offset%4 == 0 && "Misaligned stack offset"); |
| |
| DEBUG(errs() << "Offset : " << Offset << "\n" << "<--------->\n"); |
| |
| Offset/=4; |
| |
| bool FP = TFI->hasFP(MF); |
| |
| unsigned Reg = MI.getOperand(0).getReg(); |
| bool isKill = MI.getOpcode() == XCore::STWFI && MI.getOperand(0).isKill(); |
| |
| assert(XCore::GRRegsRegisterClass->contains(Reg) && |
| "Unexpected register operand"); |
| |
| MachineBasicBlock &MBB = *MI.getParent(); |
| |
| if (FP) { |
| bool isUs = isImmUs(Offset); |
| |
| if (!isUs) { |
| if (!RS) |
| report_fatal_error("eliminateFrameIndex Frame size too big: " + |
| Twine(Offset)); |
| unsigned ScratchReg = RS->scavengeRegister(XCore::GRRegsRegisterClass, II, |
| SPAdj); |
| loadConstant(MBB, II, ScratchReg, Offset, dl); |
| switch (MI.getOpcode()) { |
| case XCore::LDWFI: |
| BuildMI(MBB, II, dl, TII.get(XCore::LDW_3r), Reg) |
| .addReg(FrameReg) |
| .addReg(ScratchReg, RegState::Kill); |
| break; |
| case XCore::STWFI: |
| BuildMI(MBB, II, dl, TII.get(XCore::STW_3r)) |
| .addReg(Reg, getKillRegState(isKill)) |
| .addReg(FrameReg) |
| .addReg(ScratchReg, RegState::Kill); |
| break; |
| case XCore::LDAWFI: |
| BuildMI(MBB, II, dl, TII.get(XCore::LDAWF_l3r), Reg) |
| .addReg(FrameReg) |
| .addReg(ScratchReg, RegState::Kill); |
| break; |
| default: |
| llvm_unreachable("Unexpected Opcode"); |
| } |
| } else { |
| switch (MI.getOpcode()) { |
| case XCore::LDWFI: |
| BuildMI(MBB, II, dl, TII.get(XCore::LDW_2rus), Reg) |
| .addReg(FrameReg) |
| .addImm(Offset); |
| break; |
| case XCore::STWFI: |
| BuildMI(MBB, II, dl, TII.get(XCore::STW_2rus)) |
| .addReg(Reg, getKillRegState(isKill)) |
| .addReg(FrameReg) |
| .addImm(Offset); |
| break; |
| case XCore::LDAWFI: |
| BuildMI(MBB, II, dl, TII.get(XCore::LDAWF_l2rus), Reg) |
| .addReg(FrameReg) |
| .addImm(Offset); |
| break; |
| default: |
| llvm_unreachable("Unexpected Opcode"); |
| } |
| } |
| } else { |
| bool isU6 = isImmU6(Offset); |
| if (!isU6 && !isImmU16(Offset)) |
| report_fatal_error("eliminateFrameIndex Frame size too big: " + |
| Twine(Offset)); |
| |
| switch (MI.getOpcode()) { |
| int NewOpcode; |
| case XCore::LDWFI: |
| NewOpcode = (isU6) ? XCore::LDWSP_ru6 : XCore::LDWSP_lru6; |
| BuildMI(MBB, II, dl, TII.get(NewOpcode), Reg) |
| .addImm(Offset); |
| break; |
| case XCore::STWFI: |
| NewOpcode = (isU6) ? XCore::STWSP_ru6 : XCore::STWSP_lru6; |
| BuildMI(MBB, II, dl, TII.get(NewOpcode)) |
| .addReg(Reg, getKillRegState(isKill)) |
| .addImm(Offset); |
| break; |
| case XCore::LDAWFI: |
| NewOpcode = (isU6) ? XCore::LDAWSP_ru6 : XCore::LDAWSP_lru6; |
| BuildMI(MBB, II, dl, TII.get(NewOpcode), Reg) |
| .addImm(Offset); |
| break; |
| default: |
| llvm_unreachable("Unexpected Opcode"); |
| } |
| } |
| // Erase old instruction. |
| MBB.erase(II); |
| } |
| |
| void XCoreRegisterInfo:: |
| loadConstant(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, |
| unsigned DstReg, int64_t Value, DebugLoc dl) const { |
| // TODO use mkmsk if possible. |
| if (!isImmU16(Value)) { |
| // TODO use constant pool. |
| report_fatal_error("loadConstant value too big " + Twine(Value)); |
| } |
| int Opcode = isImmU6(Value) ? XCore::LDC_ru6 : XCore::LDC_lru6; |
| BuildMI(MBB, I, dl, TII.get(Opcode), DstReg).addImm(Value); |
| } |
| |
| unsigned XCoreRegisterInfo::getFrameRegister(const MachineFunction &MF) const { |
| const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering(); |
| |
| return TFI->hasFP(MF) ? XCore::R10 : XCore::SP; |
| } |