| //===- MipsRegisterInfo.cpp - MIPS 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 MIPS implementation of the TargetRegisterInfo class. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #define DEBUG_TYPE "mips-reg-info" |
| |
| #include "Mips.h" |
| #include "MipsSubtarget.h" |
| #include "MipsRegisterInfo.h" |
| #include "MipsMachineFunction.h" |
| #include "llvm/Constants.h" |
| #include "llvm/Type.h" |
| #include "llvm/Function.h" |
| #include "llvm/CodeGen/ValueTypes.h" |
| #include "llvm/CodeGen/MachineInstrBuilder.h" |
| #include "llvm/CodeGen/MachineFunction.h" |
| #include "llvm/CodeGen/MachineFrameInfo.h" |
| #include "llvm/CodeGen/MachineLocation.h" |
| #include "llvm/Target/TargetFrameLowering.h" |
| #include "llvm/Target/TargetMachine.h" |
| #include "llvm/Target/TargetOptions.h" |
| #include "llvm/Target/TargetInstrInfo.h" |
| #include "llvm/Support/CommandLine.h" |
| #include "llvm/Support/Debug.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/raw_ostream.h" |
| #include "llvm/ADT/BitVector.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "MipsGenRegisterDesc.inc" |
| #include "MipsGenRegisterInfo.inc" |
| |
| using namespace llvm; |
| |
| MipsRegisterInfo::MipsRegisterInfo(const MipsSubtarget &ST, |
| const TargetInstrInfo &tii) |
| : MipsGenRegisterInfo(MipsRegDesc, MipsRegInfoDesc, |
| Mips::ADJCALLSTACKDOWN, Mips::ADJCALLSTACKUP), |
| Subtarget(ST), TII(tii) {} |
| |
| /// getRegisterNumbering - Given the enum value for some register, e.g. |
| /// Mips::RA, return the number that it corresponds to (e.g. 31). |
| unsigned MipsRegisterInfo:: |
| getRegisterNumbering(unsigned RegEnum) |
| { |
| switch (RegEnum) { |
| case Mips::ZERO : case Mips::F0 : case Mips::D0 : return 0; |
| case Mips::AT : case Mips::F1 : return 1; |
| case Mips::V0 : case Mips::F2 : case Mips::D1 : return 2; |
| case Mips::V1 : case Mips::F3 : return 3; |
| case Mips::A0 : case Mips::F4 : case Mips::D2 : return 4; |
| case Mips::A1 : case Mips::F5 : return 5; |
| case Mips::A2 : case Mips::F6 : case Mips::D3 : return 6; |
| case Mips::A3 : case Mips::F7 : return 7; |
| case Mips::T0 : case Mips::F8 : case Mips::D4 : return 8; |
| case Mips::T1 : case Mips::F9 : return 9; |
| case Mips::T2 : case Mips::F10: case Mips::D5: return 10; |
| case Mips::T3 : case Mips::F11: return 11; |
| case Mips::T4 : case Mips::F12: case Mips::D6: return 12; |
| case Mips::T5 : case Mips::F13: return 13; |
| case Mips::T6 : case Mips::F14: case Mips::D7: return 14; |
| case Mips::T7 : case Mips::F15: return 15; |
| case Mips::S0 : case Mips::F16: case Mips::D8: return 16; |
| case Mips::S1 : case Mips::F17: return 17; |
| case Mips::S2 : case Mips::F18: case Mips::D9: return 18; |
| case Mips::S3 : case Mips::F19: return 19; |
| case Mips::S4 : case Mips::F20: case Mips::D10: return 20; |
| case Mips::S5 : case Mips::F21: return 21; |
| case Mips::S6 : case Mips::F22: case Mips::D11: return 22; |
| case Mips::S7 : case Mips::F23: return 23; |
| case Mips::T8 : case Mips::F24: case Mips::D12: return 24; |
| case Mips::T9 : case Mips::F25: return 25; |
| case Mips::K0 : case Mips::F26: case Mips::D13: return 26; |
| case Mips::K1 : case Mips::F27: return 27; |
| case Mips::GP : case Mips::F28: case Mips::D14: return 28; |
| case Mips::SP : case Mips::F29: return 29; |
| case Mips::FP : case Mips::F30: case Mips::D15: return 30; |
| case Mips::RA : case Mips::F31: return 31; |
| default: llvm_unreachable("Unknown register number!"); |
| } |
| return 0; // Not reached |
| } |
| |
| unsigned MipsRegisterInfo::getPICCallReg() { return Mips::T9; } |
| |
| //===----------------------------------------------------------------------===// |
| // Callee Saved Registers methods |
| //===----------------------------------------------------------------------===// |
| |
| /// Mips Callee Saved Registers |
| const unsigned* MipsRegisterInfo:: |
| getCalleeSavedRegs(const MachineFunction *MF) const |
| { |
| // Mips callee-save register range is $16-$23, $f20-$f30 |
| static const unsigned SingleFloatOnlyCalleeSavedRegs[] = { |
| Mips::F30, Mips::F29, Mips::F28, Mips::F27, Mips::F26, |
| Mips::F25, Mips::F24, Mips::F23, Mips::F22, Mips::F21, Mips::F20, |
| Mips::RA, Mips::FP, Mips::S7, Mips::S6, Mips::S5, Mips::S4, |
| Mips::S3, Mips::S2, Mips::S1, Mips::S0, 0 |
| }; |
| |
| static const unsigned Mips32CalleeSavedRegs[] = { |
| Mips::D15, Mips::D14, Mips::D13, Mips::D12, Mips::D11, Mips::D10, |
| Mips::RA, Mips::FP, Mips::S7, Mips::S6, Mips::S5, Mips::S4, |
| Mips::S3, Mips::S2, Mips::S1, Mips::S0, 0 |
| }; |
| |
| if (Subtarget.isSingleFloat()) |
| return SingleFloatOnlyCalleeSavedRegs; |
| else |
| return Mips32CalleeSavedRegs; |
| } |
| |
| BitVector MipsRegisterInfo:: |
| getReservedRegs(const MachineFunction &MF) const { |
| BitVector Reserved(getNumRegs()); |
| Reserved.set(Mips::ZERO); |
| Reserved.set(Mips::AT); |
| Reserved.set(Mips::K0); |
| Reserved.set(Mips::K1); |
| Reserved.set(Mips::GP); |
| Reserved.set(Mips::SP); |
| Reserved.set(Mips::FP); |
| Reserved.set(Mips::RA); |
| Reserved.set(Mips::F31); |
| Reserved.set(Mips::D15); |
| |
| // SRV4 requires that odd register can't be used. |
| if (!Subtarget.isSingleFloat() && !Subtarget.isMips32()) |
| for (unsigned FReg=(Mips::F0)+1; FReg < Mips::F30; FReg+=2) |
| Reserved.set(FReg); |
| |
| return Reserved; |
| } |
| |
| // This function eliminate ADJCALLSTACKDOWN, |
| // ADJCALLSTACKUP pseudo instructions |
| void MipsRegisterInfo:: |
| eliminateCallFramePseudoInstr(MachineFunction &MF, MachineBasicBlock &MBB, |
| MachineBasicBlock::iterator I) const { |
| // Simply discard ADJCALLSTACKDOWN, ADJCALLSTACKUP instructions. |
| MBB.erase(I); |
| } |
| |
| // FrameIndex represent objects inside a abstract stack. |
| // We must replace FrameIndex with an stack/frame pointer |
| // direct reference. |
| void MipsRegisterInfo:: |
| eliminateFrameIndex(MachineBasicBlock::iterator II, int SPAdj, |
| RegScavenger *RS) const { |
| MachineInstr &MI = *II; |
| MachineFunction &MF = *MI.getParent()->getParent(); |
| MachineFrameInfo *MFI = MF.getFrameInfo(); |
| MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>(); |
| |
| unsigned i = 0; |
| while (!MI.getOperand(i).isFI()) { |
| ++i; |
| assert(i < MI.getNumOperands() && |
| "Instr doesn't have FrameIndex operand!"); |
| } |
| |
| DEBUG(errs() << "\nFunction : " << MF.getFunction()->getName() << "\n"; |
| errs() << "<--------->\n" << MI); |
| |
| int FrameIndex = MI.getOperand(i).getIndex(); |
| int stackSize = MF.getFrameInfo()->getStackSize(); |
| int spOffset = MF.getFrameInfo()->getObjectOffset(FrameIndex); |
| |
| DEBUG(errs() << "FrameIndex : " << FrameIndex << "\n" |
| << "spOffset : " << spOffset << "\n" |
| << "stackSize : " << stackSize << "\n"); |
| |
| int Offset; |
| |
| // Calculate final offset. |
| // - There is no need to change the offset if the frame object is one of the |
| // following: an outgoing argument, pointer to a dynamically allocated |
| // stack space or a $gp restore location, |
| // - If the frame object is any of the following, its offset must be adjusted |
| // by adding the size of the stack: |
| // incoming argument, callee-saved register location or local variable. |
| if (MipsFI->isOutArgFI(FrameIndex) || MipsFI->isGPFI(FrameIndex) || |
| MipsFI->isDynAllocFI(FrameIndex)) |
| Offset = spOffset; |
| else |
| Offset = spOffset + stackSize; |
| |
| Offset += MI.getOperand(i-1).getImm(); |
| |
| DEBUG(errs() << "Offset : " << Offset << "\n" << "<--------->\n"); |
| |
| unsigned NewReg = 0; |
| int NewImm = 0; |
| MachineBasicBlock &MBB = *MI.getParent(); |
| bool ATUsed; |
| unsigned FrameReg; |
| const std::vector<CalleeSavedInfo> &CSI = MFI->getCalleeSavedInfo(); |
| int MinCSFI = 0; |
| int MaxCSFI = -1; |
| |
| if (CSI.size()) { |
| MinCSFI = CSI[0].getFrameIdx(); |
| MaxCSFI = CSI[CSI.size() - 1].getFrameIdx(); |
| } |
| |
| // The following stack frame objects are always referenced relative to $sp: |
| // 1. Outgoing arguments. |
| // 2. Pointer to dynamically allocated stack space. |
| // 3. Locations for callee-saved registers. |
| // Everything else is referenced relative to whatever register |
| // getFrameRegister() returns. |
| if (MipsFI->isOutArgFI(FrameIndex) || MipsFI->isDynAllocFI(FrameIndex) || |
| (FrameIndex >= MinCSFI && FrameIndex <= MaxCSFI)) |
| FrameReg = Mips::SP; |
| else |
| FrameReg = getFrameRegister(MF); |
| |
| // Offset fits in the 16-bit field |
| if (Offset < 0x8000 && Offset >= -0x8000) { |
| NewReg = FrameReg; |
| NewImm = Offset; |
| ATUsed = false; |
| } |
| else { |
| const TargetInstrInfo *TII = MF.getTarget().getInstrInfo(); |
| DebugLoc DL = II->getDebugLoc(); |
| int ImmLo = (short)(Offset & 0xffff); |
| int ImmHi = (((unsigned)Offset & 0xffff0000) >> 16) + |
| ((Offset & 0x8000) != 0); |
| |
| // FIXME: change this when mips goes MC". |
| BuildMI(MBB, II, DL, TII->get(Mips::NOAT)); |
| BuildMI(MBB, II, DL, TII->get(Mips::LUi), Mips::AT).addImm(ImmHi); |
| BuildMI(MBB, II, DL, TII->get(Mips::ADDu), Mips::AT).addReg(FrameReg) |
| .addReg(Mips::AT); |
| NewReg = Mips::AT; |
| NewImm = ImmLo; |
| |
| ATUsed = true; |
| } |
| |
| // FIXME: change this when mips goes MC". |
| if (ATUsed) |
| BuildMI(MBB, ++II, MI.getDebugLoc(), TII.get(Mips::ATMACRO)); |
| |
| MI.getOperand(i).ChangeToRegister(NewReg, false); |
| MI.getOperand(i-1).ChangeToImmediate(NewImm); |
| } |
| |
| unsigned MipsRegisterInfo:: |
| getRARegister() const { |
| return Mips::RA; |
| } |
| |
| unsigned MipsRegisterInfo:: |
| getFrameRegister(const MachineFunction &MF) const { |
| const TargetFrameLowering *TFI = MF.getTarget().getFrameLowering(); |
| |
| return TFI->hasFP(MF) ? Mips::FP : Mips::SP; |
| } |
| |
| unsigned MipsRegisterInfo:: |
| getEHExceptionRegister() const { |
| llvm_unreachable("What is the exception register"); |
| return 0; |
| } |
| |
| unsigned MipsRegisterInfo:: |
| getEHHandlerRegister() const { |
| llvm_unreachable("What is the exception handler register"); |
| return 0; |
| } |
| |
| int MipsRegisterInfo:: |
| getDwarfRegNum(unsigned RegNum, bool isEH) const { |
| return MipsGenRegisterInfo::getDwarfRegNumFull(RegNum, 0); |
| } |
| |
| int MipsRegisterInfo::getLLVMRegNum(unsigned DwarfRegNo, bool isEH) const { |
| return MipsGenRegisterInfo::getLLVMRegNumFull(DwarfRegNo,0); |
| } |