-//===- Thumb2InstrInfo.cpp - Thumb-2 Instruction Information --------*- C++ -*-===//
+//===- Thumb2InstrInfo.cpp - Thumb-2 Instruction Information ----*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
//
//===----------------------------------------------------------------------===//
-#include "ARMInstrInfo.h"
+#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"
return 0;
}
-unsigned Thumb2InstrInfo::getOpcode(ARMII::Op Op) const {
- switch (Op) {
- case ARMII::ADDri: return ARM::t2ADDri;
- case ARMII::ADDrs: return ARM::t2ADDrs;
- case ARMII::ADDrr: return ARM::t2ADDrr;
- case ARMII::B: return ARM::t2B;
- case ARMII::Bcc: return ARM::t2Bcc;
- case ARMII::BX_RET: return ARM::tBX_RET;
- case ARMII::LDRrr: return ARM::t2LDRs;
- case ARMII::LDRri: return ARM::t2LDRi12;
- case ARMII::MOVr: return ARM::t2MOVr;
- case ARMII::STRrr: return ARM::t2STRs;
- case ARMII::STRri: return ARM::t2STRi12;
- case ARMII::SUBri: return ARM::t2SUBri;
- case ARMII::SUBrs: return ARM::t2SUBrs;
- case ARMII::SUBrr: return ARM::t2SUBrr;
- default:
- break;
- }
-
- return 0;
-}
-
bool
Thumb2InstrInfo::BlockHasNoFallThrough(const MachineBasicBlock &MBB) const {
if (MBB.empty()) return false;
case ARM::t2LDM_RET:
case ARM::t2B: // Uncond branch.
case ARM::t2BR_JT: // Jumptable branch.
+ case ARM::t2TBB: // Table branch byte.
+ case ARM::t2TBH: // Table branch halfword.
case ARM::tBR_JTr: // Jumptable branch (16-bit version).
case ARM::tBX_RET:
case ARM::tBX_RET_vararg:
case ARM::tPOP_RET:
case ARM::tB:
+ case ARM::tBRIND:
return true;
default:
break;
if (DestRC == ARM::GPRRegisterClass &&
SrcRC == ARM::GPRRegisterClass) {
- AddDefaultCC(AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::t2MOVr),
- DestReg).addReg(SrcReg)));
+ BuildMI(MBB, I, DL, get(ARM::tMOVgpr2gpr), DestReg).addReg(SrcReg);
return true;
} else if (DestRC == ARM::GPRRegisterClass &&
- SrcRC == ARM::tGPRRegisterClass) {
+ SrcRC == ARM::tGPRRegisterClass) {
BuildMI(MBB, I, DL, get(ARM::tMOVtgpr2gpr), DestReg).addReg(SrcReg);
return true;
} else if (DestRC == ARM::tGPRRegisterClass &&
// Handle SPR, DPR, and QPR copies.
return ARMBaseInstrInfo::copyRegToReg(MBB, I, DestReg, SrcReg, DestRC, SrcRC);
}
+
+void Thumb2InstrInfo::
+storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
+ unsigned SrcReg, bool isKill, int FI,
+ const TargetRegisterClass *RC) const {
+ DebugLoc DL = DebugLoc::getUnknownLoc();
+ if (I != MBB.end()) DL = I->getDebugLoc();
+
+ if (RC == ARM::GPRRegisterClass) {
+ 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);
+}
+
+void Thumb2InstrInfo::
+loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
+ unsigned DestReg, int FI,
+ const TargetRegisterClass *RC) const {
+ DebugLoc DL = DebugLoc::getUnknownLoc();
+ if (I != MBB.end()) DL = I->getDebugLoc();
+
+ if (RC == ARM::GPRRegisterClass) {
+ 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);
+}
+
+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;
+ }
+
+ 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;
+ 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.
+ AddDefaultCC(AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
+ .addReg(BaseReg, RegState::Kill)
+ .addImm(ThisVal)));
+
+ 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();
+
+ bool isSP = FrameReg == ARM::SP;
+ if (Offset == 0) {
+ // Turn it into a move.
+ MI.setDesc(TII.get(ARM::tMOVgpr2gpr));
+ MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
+ MI.RemoveOperand(FrameRegIdx+1);
+ Offset = 0;
+ return true;
+ }
+
+ 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);
+ Offset = 0;
+ return true;
+ }
+ // Another common case: imm12.
+ if (Offset < 4096) {
+ 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);
+ 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);
+ } else {
+
+ // AddrMode4 cannot handle any offset.
+ if (AddrMode == ARMII::AddrMode4)
+ 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 {
+ // VFP and NEON address modes.
+ int InstrOffs = 0;
+ if (AddrMode == ARMII::AddrMode5) {
+ const MachineOperand &OffOp = MI.getOperand(FrameRegIdx+1);
+ 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;
+ }
+ }
+
+ 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;
+}
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