1 //===- Thumb2InstrInfo.cpp - Thumb-2 Instruction Information ----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file contains the Thumb-2 implementation of the TargetInstrInfo class.
12 //===----------------------------------------------------------------------===//
14 #include "Thumb2InstrInfo.h"
16 #include "ARMConstantPoolValue.h"
17 #include "ARMAddressingModes.h"
18 #include "ARMGenInstrInfo.inc"
19 #include "ARMMachineFunctionInfo.h"
20 #include "llvm/CodeGen/MachineFrameInfo.h"
21 #include "llvm/CodeGen/MachineInstrBuilder.h"
22 #include "llvm/CodeGen/MachineMemOperand.h"
23 #include "llvm/CodeGen/PseudoSourceValue.h"
24 #include "llvm/ADT/SmallVector.h"
25 #include "Thumb2InstrInfo.h"
29 Thumb2InstrInfo::Thumb2InstrInfo(const ARMSubtarget &STI)
30 : ARMBaseInstrInfo(STI), RI(*this, STI) {
33 unsigned Thumb2InstrInfo::getUnindexedOpcode(unsigned Opc) const {
39 Thumb2InstrInfo::copyRegToReg(MachineBasicBlock &MBB,
40 MachineBasicBlock::iterator I,
41 unsigned DestReg, unsigned SrcReg,
42 const TargetRegisterClass *DestRC,
43 const TargetRegisterClass *SrcRC) const {
45 if (I != MBB.end()) DL = I->getDebugLoc();
47 if (DestRC == ARM::GPRRegisterClass) {
48 if (SrcRC == ARM::GPRRegisterClass) {
49 BuildMI(MBB, I, DL, get(ARM::tMOVgpr2gpr), DestReg).addReg(SrcReg);
51 } else if (SrcRC == ARM::tGPRRegisterClass) {
52 BuildMI(MBB, I, DL, get(ARM::tMOVtgpr2gpr), DestReg).addReg(SrcReg);
55 } else if (DestRC == ARM::tGPRRegisterClass) {
56 if (SrcRC == ARM::GPRRegisterClass) {
57 BuildMI(MBB, I, DL, get(ARM::tMOVgpr2tgpr), DestReg).addReg(SrcReg);
59 } else if (SrcRC == ARM::tGPRRegisterClass) {
60 BuildMI(MBB, I, DL, get(ARM::tMOVr), DestReg).addReg(SrcReg);
65 // Handle SPR, DPR, and QPR copies.
66 return ARMBaseInstrInfo::copyRegToReg(MBB, I, DestReg, SrcReg, DestRC, SrcRC);
69 void Thumb2InstrInfo::
70 storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
71 unsigned SrcReg, bool isKill, int FI,
72 const TargetRegisterClass *RC,
73 const TargetRegisterInfo *TRI) const {
74 if (RC == ARM::GPRRegisterClass || RC == ARM::tGPRRegisterClass) {
76 if (I != MBB.end()) DL = I->getDebugLoc();
78 MachineFunction &MF = *MBB.getParent();
79 MachineFrameInfo &MFI = *MF.getFrameInfo();
80 MachineMemOperand *MMO =
81 MF.getMachineMemOperand(PseudoSourceValue::getFixedStack(FI),
82 MachineMemOperand::MOStore, 0,
83 MFI.getObjectSize(FI),
84 MFI.getObjectAlignment(FI));
85 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::t2STRi12))
86 .addReg(SrcReg, getKillRegState(isKill))
87 .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
91 ARMBaseInstrInfo::storeRegToStackSlot(MBB, I, SrcReg, isKill, FI, RC, TRI);
94 void Thumb2InstrInfo::
95 loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
96 unsigned DestReg, int FI,
97 const TargetRegisterClass *RC,
98 const TargetRegisterInfo *TRI) const {
99 if (RC == ARM::GPRRegisterClass || RC == ARM::tGPRRegisterClass) {
101 if (I != MBB.end()) DL = I->getDebugLoc();
103 MachineFunction &MF = *MBB.getParent();
104 MachineFrameInfo &MFI = *MF.getFrameInfo();
105 MachineMemOperand *MMO =
106 MF.getMachineMemOperand(PseudoSourceValue::getFixedStack(FI),
107 MachineMemOperand::MOLoad, 0,
108 MFI.getObjectSize(FI),
109 MFI.getObjectAlignment(FI));
110 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::t2LDRi12), DestReg)
111 .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
115 ARMBaseInstrInfo::loadRegFromStackSlot(MBB, I, DestReg, FI, RC, TRI);
118 void llvm::emitT2RegPlusImmediate(MachineBasicBlock &MBB,
119 MachineBasicBlock::iterator &MBBI, DebugLoc dl,
120 unsigned DestReg, unsigned BaseReg, int NumBytes,
121 ARMCC::CondCodes Pred, unsigned PredReg,
122 const ARMBaseInstrInfo &TII) {
123 bool isSub = NumBytes < 0;
124 if (isSub) NumBytes = -NumBytes;
126 // If profitable, use a movw or movt to materialize the offset.
127 // FIXME: Use the scavenger to grab a scratch register.
128 if (DestReg != ARM::SP && DestReg != BaseReg &&
130 ARM_AM::getT2SOImmVal(NumBytes) == -1) {
132 if (NumBytes < 65536) {
133 // Use a movw to materialize the 16-bit constant.
134 BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVi16), DestReg)
136 .addImm((unsigned)Pred).addReg(PredReg).addReg(0);
138 } else if ((NumBytes & 0xffff) == 0) {
139 // Use a movt to materialize the 32-bit constant.
140 BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVTi16), DestReg)
142 .addImm(NumBytes >> 16)
143 .addImm((unsigned)Pred).addReg(PredReg).addReg(0);
149 BuildMI(MBB, MBBI, dl, TII.get(ARM::t2SUBrr), DestReg)
150 .addReg(BaseReg, RegState::Kill)
151 .addReg(DestReg, RegState::Kill)
152 .addImm((unsigned)Pred).addReg(PredReg).addReg(0);
154 BuildMI(MBB, MBBI, dl, TII.get(ARM::t2ADDrr), DestReg)
155 .addReg(DestReg, RegState::Kill)
156 .addReg(BaseReg, RegState::Kill)
157 .addImm((unsigned)Pred).addReg(PredReg).addReg(0);
164 unsigned ThisVal = NumBytes;
166 if (DestReg == ARM::SP && BaseReg != ARM::SP) {
167 // mov sp, rn. Note t2MOVr cannot be used.
168 BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVgpr2gpr),DestReg).addReg(BaseReg);
173 bool HasCCOut = true;
174 if (BaseReg == ARM::SP) {
176 if (DestReg == ARM::SP && (ThisVal < ((1 << 7)-1) * 4)) {
177 assert((ThisVal & 3) == 0 && "Stack update is not multiple of 4?");
178 Opc = isSub ? ARM::tSUBspi : ARM::tADDspi;
179 // FIXME: Fix Thumb1 immediate encoding.
180 BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
181 .addReg(BaseReg).addImm(ThisVal/4);
186 // sub rd, sp, so_imm
187 Opc = isSub ? ARM::t2SUBrSPi : ARM::t2ADDrSPi;
188 if (ARM_AM::getT2SOImmVal(NumBytes) != -1) {
191 // FIXME: Move this to ARMAddressingModes.h?
192 unsigned RotAmt = CountLeadingZeros_32(ThisVal);
193 ThisVal = ThisVal & ARM_AM::rotr32(0xff000000U, RotAmt);
194 NumBytes &= ~ThisVal;
195 assert(ARM_AM::getT2SOImmVal(ThisVal) != -1 &&
196 "Bit extraction didn't work?");
199 assert(DestReg != ARM::SP && BaseReg != ARM::SP);
200 Opc = isSub ? ARM::t2SUBri : ARM::t2ADDri;
201 if (ARM_AM::getT2SOImmVal(NumBytes) != -1) {
203 } else if (ThisVal < 4096) {
204 Opc = isSub ? ARM::t2SUBri12 : ARM::t2ADDri12;
208 // FIXME: Move this to ARMAddressingModes.h?
209 unsigned RotAmt = CountLeadingZeros_32(ThisVal);
210 ThisVal = ThisVal & ARM_AM::rotr32(0xff000000U, RotAmt);
211 NumBytes &= ~ThisVal;
212 assert(ARM_AM::getT2SOImmVal(ThisVal) != -1 &&
213 "Bit extraction didn't work?");
217 // Build the new ADD / SUB.
218 MachineInstrBuilder MIB =
219 AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
220 .addReg(BaseReg, RegState::Kill)
230 negativeOffsetOpcode(unsigned opcode)
233 case ARM::t2LDRi12: return ARM::t2LDRi8;
234 case ARM::t2LDRHi12: return ARM::t2LDRHi8;
235 case ARM::t2LDRBi12: return ARM::t2LDRBi8;
236 case ARM::t2LDRSHi12: return ARM::t2LDRSHi8;
237 case ARM::t2LDRSBi12: return ARM::t2LDRSBi8;
238 case ARM::t2STRi12: return ARM::t2STRi8;
239 case ARM::t2STRBi12: return ARM::t2STRBi8;
240 case ARM::t2STRHi12: return ARM::t2STRHi8;
260 positiveOffsetOpcode(unsigned opcode)
263 case ARM::t2LDRi8: return ARM::t2LDRi12;
264 case ARM::t2LDRHi8: return ARM::t2LDRHi12;
265 case ARM::t2LDRBi8: return ARM::t2LDRBi12;
266 case ARM::t2LDRSHi8: return ARM::t2LDRSHi12;
267 case ARM::t2LDRSBi8: return ARM::t2LDRSBi12;
268 case ARM::t2STRi8: return ARM::t2STRi12;
269 case ARM::t2STRBi8: return ARM::t2STRBi12;
270 case ARM::t2STRHi8: return ARM::t2STRHi12;
275 case ARM::t2LDRSHi12:
276 case ARM::t2LDRSBi12:
290 immediateOffsetOpcode(unsigned opcode)
293 case ARM::t2LDRs: return ARM::t2LDRi12;
294 case ARM::t2LDRHs: return ARM::t2LDRHi12;
295 case ARM::t2LDRBs: return ARM::t2LDRBi12;
296 case ARM::t2LDRSHs: return ARM::t2LDRSHi12;
297 case ARM::t2LDRSBs: return ARM::t2LDRSBi12;
298 case ARM::t2STRs: return ARM::t2STRi12;
299 case ARM::t2STRBs: return ARM::t2STRBi12;
300 case ARM::t2STRHs: return ARM::t2STRHi12;
305 case ARM::t2LDRSHi12:
306 case ARM::t2LDRSBi12:
327 bool llvm::rewriteT2FrameIndex(MachineInstr &MI, unsigned FrameRegIdx,
328 unsigned FrameReg, int &Offset,
329 const ARMBaseInstrInfo &TII) {
330 unsigned Opcode = MI.getOpcode();
331 const TargetInstrDesc &Desc = MI.getDesc();
332 unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
335 // Memory operands in inline assembly always use AddrModeT2_i12.
336 if (Opcode == ARM::INLINEASM)
337 AddrMode = ARMII::AddrModeT2_i12; // FIXME. mode for thumb2?
339 if (Opcode == ARM::t2ADDri || Opcode == ARM::t2ADDri12) {
340 Offset += MI.getOperand(FrameRegIdx+1).getImm();
343 if (Offset == 0 && getInstrPredicate(&MI, PredReg) == ARMCC::AL) {
344 // Turn it into a move.
345 MI.setDesc(TII.get(ARM::tMOVgpr2gpr));
346 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
347 // Remove offset and remaining explicit predicate operands.
348 do MI.RemoveOperand(FrameRegIdx+1);
349 while (MI.getNumOperands() > FrameRegIdx+1 &&
350 (!MI.getOperand(FrameRegIdx+1).isReg() ||
351 !MI.getOperand(FrameRegIdx+1).isImm()));
355 bool isSP = FrameReg == ARM::SP;
356 bool HasCCOut = Opcode != ARM::t2ADDri12;
361 MI.setDesc(TII.get(isSP ? ARM::t2SUBrSPi : ARM::t2SUBri));
363 MI.setDesc(TII.get(isSP ? ARM::t2ADDrSPi : ARM::t2ADDri));
366 // Common case: small offset, fits into instruction.
367 if (ARM_AM::getT2SOImmVal(Offset) != -1) {
368 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
369 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
370 // Add cc_out operand if the original instruction did not have one.
372 MI.addOperand(MachineOperand::CreateReg(0, false));
376 // Another common case: imm12.
378 (!HasCCOut || MI.getOperand(MI.getNumOperands()-1).getReg() == 0)) {
379 unsigned NewOpc = isSP
380 ? (isSub ? ARM::t2SUBrSPi12 : ARM::t2ADDrSPi12)
381 : (isSub ? ARM::t2SUBri12 : ARM::t2ADDri12);
382 MI.setDesc(TII.get(NewOpc));
383 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
384 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
385 // Remove the cc_out operand.
387 MI.RemoveOperand(MI.getNumOperands()-1);
392 // Otherwise, extract 8 adjacent bits from the immediate into this
394 unsigned RotAmt = CountLeadingZeros_32(Offset);
395 unsigned ThisImmVal = Offset & ARM_AM::rotr32(0xff000000U, RotAmt);
397 // We will handle these bits from offset, clear them.
398 Offset &= ~ThisImmVal;
400 assert(ARM_AM::getT2SOImmVal(ThisImmVal) != -1 &&
401 "Bit extraction didn't work?");
402 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal);
403 // Add cc_out operand if the original instruction did not have one.
405 MI.addOperand(MachineOperand::CreateReg(0, false));
409 // AddrMode4 and AddrMode6 cannot handle any offset.
410 if (AddrMode == ARMII::AddrMode4 || AddrMode == ARMII::AddrMode6)
413 // AddrModeT2_so cannot handle any offset. If there is no offset
414 // register then we change to an immediate version.
415 unsigned NewOpc = Opcode;
416 if (AddrMode == ARMII::AddrModeT2_so) {
417 unsigned OffsetReg = MI.getOperand(FrameRegIdx+1).getReg();
418 if (OffsetReg != 0) {
419 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
423 MI.RemoveOperand(FrameRegIdx+1);
424 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(0);
425 NewOpc = immediateOffsetOpcode(Opcode);
426 AddrMode = ARMII::AddrModeT2_i12;
429 unsigned NumBits = 0;
431 if (AddrMode == ARMII::AddrModeT2_i8 || AddrMode == ARMII::AddrModeT2_i12) {
432 // i8 supports only negative, and i12 supports only positive, so
433 // based on Offset sign convert Opcode to the appropriate
435 Offset += MI.getOperand(FrameRegIdx+1).getImm();
437 NewOpc = negativeOffsetOpcode(Opcode);
442 NewOpc = positiveOffsetOpcode(Opcode);
445 } else if (AddrMode == ARMII::AddrMode5) {
447 const MachineOperand &OffOp = MI.getOperand(FrameRegIdx+1);
448 int InstrOffs = ARM_AM::getAM5Offset(OffOp.getImm());
449 if (ARM_AM::getAM5Op(OffOp.getImm()) == ARM_AM::sub)
453 Offset += InstrOffs * 4;
454 assert((Offset & (Scale-1)) == 0 && "Can't encode this offset!");
460 llvm_unreachable("Unsupported addressing mode!");
463 if (NewOpc != Opcode)
464 MI.setDesc(TII.get(NewOpc));
466 MachineOperand &ImmOp = MI.getOperand(FrameRegIdx+1);
468 // Attempt to fold address computation
469 // Common case: small offset, fits into instruction.
470 int ImmedOffset = Offset / Scale;
471 unsigned Mask = (1 << NumBits) - 1;
472 if ((unsigned)Offset <= Mask * Scale) {
473 // Replace the FrameIndex with fp/sp
474 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
476 if (AddrMode == ARMII::AddrMode5)
477 // FIXME: Not consistent.
478 ImmedOffset |= 1 << NumBits;
480 ImmedOffset = -ImmedOffset;
482 ImmOp.ChangeToImmediate(ImmedOffset);
487 // Otherwise, offset doesn't fit. Pull in what we can to simplify
488 ImmedOffset = ImmedOffset & Mask;
490 if (AddrMode == ARMII::AddrMode5)
491 // FIXME: Not consistent.
492 ImmedOffset |= 1 << NumBits;
494 ImmedOffset = -ImmedOffset;
495 if (ImmedOffset == 0)
496 // Change the opcode back if the encoded offset is zero.
497 MI.setDesc(TII.get(positiveOffsetOpcode(NewOpc)));
500 ImmOp.ChangeToImmediate(ImmedOffset);
501 Offset &= ~(Mask*Scale);
504 Offset = (isSub) ? -Offset : Offset;