diff options
Diffstat (limited to 'contrib/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp')
| -rw-r--r-- | contrib/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp | 504 |
1 files changed, 504 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp b/contrib/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp new file mode 100644 index 0000000..531d5e9 --- /dev/null +++ b/contrib/llvm/lib/Target/ARM/Thumb2InstrInfo.cpp @@ -0,0 +1,504 @@ +//===- Thumb2InstrInfo.cpp - Thumb-2 Instruction 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 Thumb-2 implementation of the TargetInstrInfo class. +// +//===----------------------------------------------------------------------===// + +#include "Thumb2InstrInfo.h" +#include "ARM.h" +#include "ARMConstantPoolValue.h" +#include "ARMAddressingModes.h" +#include "ARMGenInstrInfo.inc" +#include "ARMMachineFunctionInfo.h" +#include "llvm/CodeGen/MachineFrameInfo.h" +#include "llvm/CodeGen/MachineInstrBuilder.h" +#include "llvm/CodeGen/MachineMemOperand.h" +#include "llvm/CodeGen/PseudoSourceValue.h" +#include "llvm/ADT/SmallVector.h" +#include "Thumb2InstrInfo.h" + +using namespace llvm; + +Thumb2InstrInfo::Thumb2InstrInfo(const ARMSubtarget &STI) + : ARMBaseInstrInfo(STI), RI(*this, STI) { +} + +unsigned Thumb2InstrInfo::getUnindexedOpcode(unsigned Opc) const { + // FIXME + return 0; +} + +bool +Thumb2InstrInfo::copyRegToReg(MachineBasicBlock &MBB, + MachineBasicBlock::iterator I, + unsigned DestReg, unsigned SrcReg, + const TargetRegisterClass *DestRC, + const TargetRegisterClass *SrcRC, + DebugLoc DL) const { + if (DestRC == ARM::GPRRegisterClass) { + if (SrcRC == ARM::GPRRegisterClass) { + BuildMI(MBB, I, DL, get(ARM::tMOVgpr2gpr), DestReg).addReg(SrcReg); + return true; + } else if (SrcRC == ARM::tGPRRegisterClass) { + BuildMI(MBB, I, DL, get(ARM::tMOVtgpr2gpr), DestReg).addReg(SrcReg); + return true; + } + } else if (DestRC == ARM::tGPRRegisterClass) { + if (SrcRC == ARM::GPRRegisterClass) { + BuildMI(MBB, I, DL, get(ARM::tMOVgpr2tgpr), DestReg).addReg(SrcReg); + return true; + } else if (SrcRC == ARM::tGPRRegisterClass) { + BuildMI(MBB, I, DL, get(ARM::tMOVr), DestReg).addReg(SrcReg); + return true; + } + } + + // Handle SPR, DPR, and QPR copies. + return ARMBaseInstrInfo::copyRegToReg(MBB, I, DestReg, SrcReg, DestRC, SrcRC, DL); +} + +void Thumb2InstrInfo:: +storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, + unsigned SrcReg, bool isKill, int FI, + const TargetRegisterClass *RC, + const TargetRegisterInfo *TRI) const { + if (RC == ARM::GPRRegisterClass || RC == ARM::tGPRRegisterClass) { + DebugLoc DL; + if (I != MBB.end()) DL = I->getDebugLoc(); + + MachineFunction &MF = *MBB.getParent(); + MachineFrameInfo &MFI = *MF.getFrameInfo(); + MachineMemOperand *MMO = + MF.getMachineMemOperand(PseudoSourceValue::getFixedStack(FI), + MachineMemOperand::MOStore, 0, + MFI.getObjectSize(FI), + MFI.getObjectAlignment(FI)); + AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::t2STRi12)) + .addReg(SrcReg, getKillRegState(isKill)) + .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); + return; + } + + ARMBaseInstrInfo::storeRegToStackSlot(MBB, I, SrcReg, isKill, FI, RC, TRI); +} + +void Thumb2InstrInfo:: +loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I, + unsigned DestReg, int FI, + const TargetRegisterClass *RC, + const TargetRegisterInfo *TRI) const { + if (RC == ARM::GPRRegisterClass || RC == ARM::tGPRRegisterClass) { + DebugLoc DL; + if (I != MBB.end()) DL = I->getDebugLoc(); + + MachineFunction &MF = *MBB.getParent(); + MachineFrameInfo &MFI = *MF.getFrameInfo(); + MachineMemOperand *MMO = + MF.getMachineMemOperand(PseudoSourceValue::getFixedStack(FI), + MachineMemOperand::MOLoad, 0, + MFI.getObjectSize(FI), + MFI.getObjectAlignment(FI)); + AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::t2LDRi12), DestReg) + .addFrameIndex(FI).addImm(0).addMemOperand(MMO)); + return; + } + + ARMBaseInstrInfo::loadRegFromStackSlot(MBB, I, DestReg, FI, RC, TRI); +} + +void llvm::emitT2RegPlusImmediate(MachineBasicBlock &MBB, + MachineBasicBlock::iterator &MBBI, DebugLoc dl, + unsigned DestReg, unsigned BaseReg, int NumBytes, + ARMCC::CondCodes Pred, unsigned PredReg, + const ARMBaseInstrInfo &TII) { + bool isSub = NumBytes < 0; + if (isSub) NumBytes = -NumBytes; + + // If profitable, use a movw or movt to materialize the offset. + // FIXME: Use the scavenger to grab a scratch register. + if (DestReg != ARM::SP && DestReg != BaseReg && + NumBytes >= 4096 && + ARM_AM::getT2SOImmVal(NumBytes) == -1) { + bool Fits = false; + if (NumBytes < 65536) { + // Use a movw to materialize the 16-bit constant. + BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVi16), DestReg) + .addImm(NumBytes) + .addImm((unsigned)Pred).addReg(PredReg).addReg(0); + Fits = true; + } else if ((NumBytes & 0xffff) == 0) { + // Use a movt to materialize the 32-bit constant. + BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVTi16), DestReg) + .addReg(DestReg) + .addImm(NumBytes >> 16) + .addImm((unsigned)Pred).addReg(PredReg).addReg(0); + Fits = true; + } + + if (Fits) { + if (isSub) { + BuildMI(MBB, MBBI, dl, TII.get(ARM::t2SUBrr), DestReg) + .addReg(BaseReg, RegState::Kill) + .addReg(DestReg, RegState::Kill) + .addImm((unsigned)Pred).addReg(PredReg).addReg(0); + } else { + BuildMI(MBB, MBBI, dl, TII.get(ARM::t2ADDrr), DestReg) + .addReg(DestReg, RegState::Kill) + .addReg(BaseReg, RegState::Kill) + .addImm((unsigned)Pred).addReg(PredReg).addReg(0); + } + return; + } + } + + while (NumBytes) { + unsigned ThisVal = NumBytes; + unsigned Opc = 0; + if (DestReg == ARM::SP && BaseReg != ARM::SP) { + // mov sp, rn. Note t2MOVr cannot be used. + BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVgpr2gpr),DestReg).addReg(BaseReg); + BaseReg = ARM::SP; + continue; + } + + bool HasCCOut = true; + if (BaseReg == ARM::SP) { + // sub sp, sp, #imm7 + if (DestReg == ARM::SP && (ThisVal < ((1 << 7)-1) * 4)) { + assert((ThisVal & 3) == 0 && "Stack update is not multiple of 4?"); + Opc = isSub ? ARM::tSUBspi : ARM::tADDspi; + // FIXME: Fix Thumb1 immediate encoding. + BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg) + .addReg(BaseReg).addImm(ThisVal/4); + NumBytes = 0; + continue; + } + + // sub rd, sp, so_imm + Opc = isSub ? ARM::t2SUBrSPi : ARM::t2ADDrSPi; + if (ARM_AM::getT2SOImmVal(NumBytes) != -1) { + NumBytes = 0; + } else { + // FIXME: Move this to ARMAddressingModes.h? + unsigned RotAmt = CountLeadingZeros_32(ThisVal); + ThisVal = ThisVal & ARM_AM::rotr32(0xff000000U, RotAmt); + NumBytes &= ~ThisVal; + assert(ARM_AM::getT2SOImmVal(ThisVal) != -1 && + "Bit extraction didn't work?"); + } + } else { + assert(DestReg != ARM::SP && BaseReg != ARM::SP); + Opc = isSub ? ARM::t2SUBri : ARM::t2ADDri; + if (ARM_AM::getT2SOImmVal(NumBytes) != -1) { + NumBytes = 0; + } else if (ThisVal < 4096) { + Opc = isSub ? ARM::t2SUBri12 : ARM::t2ADDri12; + HasCCOut = false; + NumBytes = 0; + } else { + // FIXME: Move this to ARMAddressingModes.h? + unsigned RotAmt = CountLeadingZeros_32(ThisVal); + ThisVal = ThisVal & ARM_AM::rotr32(0xff000000U, RotAmt); + NumBytes &= ~ThisVal; + assert(ARM_AM::getT2SOImmVal(ThisVal) != -1 && + "Bit extraction didn't work?"); + } + } + + // Build the new ADD / SUB. + MachineInstrBuilder MIB = + AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg) + .addReg(BaseReg, RegState::Kill) + .addImm(ThisVal)); + if (HasCCOut) + AddDefaultCC(MIB); + + BaseReg = DestReg; + } +} + +static unsigned +negativeOffsetOpcode(unsigned opcode) +{ + switch (opcode) { + case ARM::t2LDRi12: return ARM::t2LDRi8; + case ARM::t2LDRHi12: return ARM::t2LDRHi8; + case ARM::t2LDRBi12: return ARM::t2LDRBi8; + case ARM::t2LDRSHi12: return ARM::t2LDRSHi8; + case ARM::t2LDRSBi12: return ARM::t2LDRSBi8; + case ARM::t2STRi12: return ARM::t2STRi8; + case ARM::t2STRBi12: return ARM::t2STRBi8; + case ARM::t2STRHi12: return ARM::t2STRHi8; + + case ARM::t2LDRi8: + case ARM::t2LDRHi8: + case ARM::t2LDRBi8: + case ARM::t2LDRSHi8: + case ARM::t2LDRSBi8: + case ARM::t2STRi8: + case ARM::t2STRBi8: + case ARM::t2STRHi8: + return opcode; + + default: + break; + } + + return 0; +} + +static unsigned +positiveOffsetOpcode(unsigned opcode) +{ + switch (opcode) { + case ARM::t2LDRi8: return ARM::t2LDRi12; + case ARM::t2LDRHi8: return ARM::t2LDRHi12; + case ARM::t2LDRBi8: return ARM::t2LDRBi12; + case ARM::t2LDRSHi8: return ARM::t2LDRSHi12; + case ARM::t2LDRSBi8: return ARM::t2LDRSBi12; + case ARM::t2STRi8: return ARM::t2STRi12; + case ARM::t2STRBi8: return ARM::t2STRBi12; + case ARM::t2STRHi8: return ARM::t2STRHi12; + + case ARM::t2LDRi12: + case ARM::t2LDRHi12: + case ARM::t2LDRBi12: + case ARM::t2LDRSHi12: + case ARM::t2LDRSBi12: + case ARM::t2STRi12: + case ARM::t2STRBi12: + case ARM::t2STRHi12: + return opcode; + + default: + break; + } + + return 0; +} + +static unsigned +immediateOffsetOpcode(unsigned opcode) +{ + switch (opcode) { + case ARM::t2LDRs: return ARM::t2LDRi12; + case ARM::t2LDRHs: return ARM::t2LDRHi12; + case ARM::t2LDRBs: return ARM::t2LDRBi12; + case ARM::t2LDRSHs: return ARM::t2LDRSHi12; + case ARM::t2LDRSBs: return ARM::t2LDRSBi12; + case ARM::t2STRs: return ARM::t2STRi12; + case ARM::t2STRBs: return ARM::t2STRBi12; + case ARM::t2STRHs: return ARM::t2STRHi12; + + case ARM::t2LDRi12: + case ARM::t2LDRHi12: + case ARM::t2LDRBi12: + case ARM::t2LDRSHi12: + case ARM::t2LDRSBi12: + case ARM::t2STRi12: + case ARM::t2STRBi12: + case ARM::t2STRHi12: + case ARM::t2LDRi8: + case ARM::t2LDRHi8: + case ARM::t2LDRBi8: + case ARM::t2LDRSHi8: + case ARM::t2LDRSBi8: + case ARM::t2STRi8: + case ARM::t2STRBi8: + case ARM::t2STRHi8: + return opcode; + + default: + break; + } + + return 0; +} + +bool llvm::rewriteT2FrameIndex(MachineInstr &MI, unsigned FrameRegIdx, + unsigned FrameReg, int &Offset, + const ARMBaseInstrInfo &TII) { + unsigned Opcode = MI.getOpcode(); + const TargetInstrDesc &Desc = MI.getDesc(); + unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask); + bool isSub = false; + + // Memory operands in inline assembly always use AddrModeT2_i12. + if (Opcode == ARM::INLINEASM) + AddrMode = ARMII::AddrModeT2_i12; // FIXME. mode for thumb2? + + if (Opcode == ARM::t2ADDri || Opcode == ARM::t2ADDri12) { + Offset += MI.getOperand(FrameRegIdx+1).getImm(); + + unsigned PredReg; + if (Offset == 0 && getInstrPredicate(&MI, PredReg) == ARMCC::AL) { + // Turn it into a move. + MI.setDesc(TII.get(ARM::tMOVgpr2gpr)); + MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); + // Remove offset and remaining explicit predicate operands. + do MI.RemoveOperand(FrameRegIdx+1); + while (MI.getNumOperands() > FrameRegIdx+1 && + (!MI.getOperand(FrameRegIdx+1).isReg() || + !MI.getOperand(FrameRegIdx+1).isImm())); + return true; + } + + bool isSP = FrameReg == ARM::SP; + bool HasCCOut = Opcode != ARM::t2ADDri12; + + if (Offset < 0) { + Offset = -Offset; + isSub = true; + MI.setDesc(TII.get(isSP ? ARM::t2SUBrSPi : ARM::t2SUBri)); + } else { + MI.setDesc(TII.get(isSP ? ARM::t2ADDrSPi : ARM::t2ADDri)); + } + + // Common case: small offset, fits into instruction. + if (ARM_AM::getT2SOImmVal(Offset) != -1) { + MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); + MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset); + // Add cc_out operand if the original instruction did not have one. + if (!HasCCOut) + MI.addOperand(MachineOperand::CreateReg(0, false)); + Offset = 0; + return true; + } + // Another common case: imm12. + if (Offset < 4096 && + (!HasCCOut || MI.getOperand(MI.getNumOperands()-1).getReg() == 0)) { + unsigned NewOpc = isSP + ? (isSub ? ARM::t2SUBrSPi12 : ARM::t2ADDrSPi12) + : (isSub ? ARM::t2SUBri12 : ARM::t2ADDri12); + MI.setDesc(TII.get(NewOpc)); + MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); + MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset); + // Remove the cc_out operand. + if (HasCCOut) + MI.RemoveOperand(MI.getNumOperands()-1); + Offset = 0; + return true; + } + + // Otherwise, extract 8 adjacent bits from the immediate into this + // t2ADDri/t2SUBri. + unsigned RotAmt = CountLeadingZeros_32(Offset); + unsigned ThisImmVal = Offset & ARM_AM::rotr32(0xff000000U, RotAmt); + + // We will handle these bits from offset, clear them. + Offset &= ~ThisImmVal; + + assert(ARM_AM::getT2SOImmVal(ThisImmVal) != -1 && + "Bit extraction didn't work?"); + MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal); + // Add cc_out operand if the original instruction did not have one. + if (!HasCCOut) + MI.addOperand(MachineOperand::CreateReg(0, false)); + + } else { + + // AddrMode4 and AddrMode6 cannot handle any offset. + if (AddrMode == ARMII::AddrMode4 || AddrMode == ARMII::AddrMode6) + return false; + + // AddrModeT2_so cannot handle any offset. If there is no offset + // register then we change to an immediate version. + unsigned NewOpc = Opcode; + if (AddrMode == ARMII::AddrModeT2_so) { + unsigned OffsetReg = MI.getOperand(FrameRegIdx+1).getReg(); + if (OffsetReg != 0) { + MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); + return Offset == 0; + } + + MI.RemoveOperand(FrameRegIdx+1); + MI.getOperand(FrameRegIdx+1).ChangeToImmediate(0); + NewOpc = immediateOffsetOpcode(Opcode); + AddrMode = ARMII::AddrModeT2_i12; + } + + unsigned NumBits = 0; + unsigned Scale = 1; + if (AddrMode == ARMII::AddrModeT2_i8 || AddrMode == ARMII::AddrModeT2_i12) { + // i8 supports only negative, and i12 supports only positive, so + // based on Offset sign convert Opcode to the appropriate + // instruction + Offset += MI.getOperand(FrameRegIdx+1).getImm(); + if (Offset < 0) { + NewOpc = negativeOffsetOpcode(Opcode); + NumBits = 8; + isSub = true; + Offset = -Offset; + } else { + NewOpc = positiveOffsetOpcode(Opcode); + NumBits = 12; + } + } else if (AddrMode == ARMII::AddrMode5) { + // VFP address mode. + const MachineOperand &OffOp = MI.getOperand(FrameRegIdx+1); + int InstrOffs = ARM_AM::getAM5Offset(OffOp.getImm()); + if (ARM_AM::getAM5Op(OffOp.getImm()) == ARM_AM::sub) + InstrOffs *= -1; + NumBits = 8; + Scale = 4; + Offset += InstrOffs * 4; + assert((Offset & (Scale-1)) == 0 && "Can't encode this offset!"); + if (Offset < 0) { + Offset = -Offset; + isSub = true; + } + } else { + llvm_unreachable("Unsupported addressing mode!"); + } + + if (NewOpc != Opcode) + MI.setDesc(TII.get(NewOpc)); + + MachineOperand &ImmOp = MI.getOperand(FrameRegIdx+1); + + // Attempt to fold address computation + // Common case: small offset, fits into instruction. + int ImmedOffset = Offset / Scale; + unsigned Mask = (1 << NumBits) - 1; + if ((unsigned)Offset <= Mask * Scale) { + // Replace the FrameIndex with fp/sp + MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false); + if (isSub) { + if (AddrMode == ARMII::AddrMode5) + // FIXME: Not consistent. + ImmedOffset |= 1 << NumBits; + else + ImmedOffset = -ImmedOffset; + } + ImmOp.ChangeToImmediate(ImmedOffset); + Offset = 0; + return true; + } + + // Otherwise, offset doesn't fit. Pull in what we can to simplify + ImmedOffset = ImmedOffset & Mask; + if (isSub) { + if (AddrMode == ARMII::AddrMode5) + // FIXME: Not consistent. + ImmedOffset |= 1 << NumBits; + else { + ImmedOffset = -ImmedOffset; + if (ImmedOffset == 0) + // Change the opcode back if the encoded offset is zero. + MI.setDesc(TII.get(positiveOffsetOpcode(NewOpc))); + } + } + ImmOp.ChangeToImmediate(ImmedOffset); + Offset &= ~(Mask*Scale); + } + + Offset = (isSub) ? -Offset : Offset; + return Offset == 0; +} |
