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 "Thumb2HazardRecognizer.h"
21 #include "Thumb2InstrInfo.h"
22 #include "llvm/CodeGen/MachineFrameInfo.h"
23 #include "llvm/CodeGen/MachineInstrBuilder.h"
24 #include "llvm/CodeGen/MachineMemOperand.h"
25 #include "llvm/CodeGen/PseudoSourceValue.h"
26 #include "llvm/ADT/SmallVector.h"
30 Thumb2InstrInfo::Thumb2InstrInfo(const ARMSubtarget &STI)
31 : ARMBaseInstrInfo(STI), RI(*this, STI) {
34 unsigned Thumb2InstrInfo::getUnindexedOpcode(unsigned Opc) const {
40 Thumb2InstrInfo::ReplaceTailWithBranchTo(MachineBasicBlock::iterator Tail,
41 MachineBasicBlock *NewDest) const {
42 MachineBasicBlock *MBB = Tail->getParent();
43 ARMFunctionInfo *AFI = MBB->getParent()->getInfo<ARMFunctionInfo>();
44 if (!AFI->hasITBlocks()) {
45 TargetInstrInfoImpl::ReplaceTailWithBranchTo(Tail, NewDest);
49 // If the first instruction of Tail is predicated, we may have to update
50 // the IT instruction.
52 ARMCC::CondCodes CC = llvm::getInstrPredicate(Tail, PredReg);
53 MachineBasicBlock::iterator MBBI = Tail;
55 // Expecting at least the t2IT instruction before it.
58 // Actually replace the tail.
59 TargetInstrInfoImpl::ReplaceTailWithBranchTo(Tail, NewDest);
62 if (CC != ARMCC::AL) {
63 MachineBasicBlock::iterator E = MBB->begin();
64 unsigned Count = 4; // At most 4 instructions in an IT block.
65 while (Count && MBBI != E) {
66 if (MBBI->isDebugValue()) {
70 if (MBBI->getOpcode() == ARM::t2IT) {
71 unsigned Mask = MBBI->getOperand(1).getImm();
73 MBBI->eraseFromParent();
75 unsigned MaskOn = 1 << Count;
76 unsigned MaskOff = ~(MaskOn - 1);
77 MBBI->getOperand(1).setImm((Mask & MaskOff) | MaskOn);
85 // Ctrl flow can reach here if branch folding is run before IT block
91 Thumb2InstrInfo::copyRegToReg(MachineBasicBlock &MBB,
92 MachineBasicBlock::iterator I,
93 unsigned DestReg, unsigned SrcReg,
94 const TargetRegisterClass *DestRC,
95 const TargetRegisterClass *SrcRC,
97 if (DestRC == ARM::GPRRegisterClass || DestRC == ARM::tcGPRRegisterClass) {
98 if (SrcRC == ARM::GPRRegisterClass || SrcRC == ARM::tcGPRRegisterClass) {
99 BuildMI(MBB, I, DL, get(ARM::tMOVgpr2gpr), DestReg).addReg(SrcReg);
101 } else if (SrcRC == ARM::tGPRRegisterClass) {
102 BuildMI(MBB, I, DL, get(ARM::tMOVtgpr2gpr), DestReg).addReg(SrcReg);
105 } else if (DestRC == ARM::tGPRRegisterClass) {
106 if (SrcRC == ARM::GPRRegisterClass || SrcRC == ARM::tcGPRRegisterClass) {
107 BuildMI(MBB, I, DL, get(ARM::tMOVgpr2tgpr), DestReg).addReg(SrcReg);
109 } else if (SrcRC == ARM::tGPRRegisterClass) {
110 BuildMI(MBB, I, DL, get(ARM::tMOVr), DestReg).addReg(SrcReg);
115 // Handle SPR, DPR, and QPR copies.
116 return ARMBaseInstrInfo::copyRegToReg(MBB, I, DestReg, SrcReg, DestRC,
120 void Thumb2InstrInfo::
121 storeRegToStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
122 unsigned SrcReg, bool isKill, int FI,
123 const TargetRegisterClass *RC,
124 const TargetRegisterInfo *TRI) const {
125 if (RC == ARM::GPRRegisterClass || RC == ARM::tGPRRegisterClass ||
126 RC == ARM::tcGPRRegisterClass) {
128 if (I != MBB.end()) DL = I->getDebugLoc();
130 MachineFunction &MF = *MBB.getParent();
131 MachineFrameInfo &MFI = *MF.getFrameInfo();
132 MachineMemOperand *MMO =
133 MF.getMachineMemOperand(PseudoSourceValue::getFixedStack(FI),
134 MachineMemOperand::MOStore, 0,
135 MFI.getObjectSize(FI),
136 MFI.getObjectAlignment(FI));
137 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::t2STRi12))
138 .addReg(SrcReg, getKillRegState(isKill))
139 .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
143 ARMBaseInstrInfo::storeRegToStackSlot(MBB, I, SrcReg, isKill, FI, RC, TRI);
146 void Thumb2InstrInfo::
147 loadRegFromStackSlot(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
148 unsigned DestReg, int FI,
149 const TargetRegisterClass *RC,
150 const TargetRegisterInfo *TRI) const {
151 if (RC == ARM::GPRRegisterClass || RC == ARM::tGPRRegisterClass ||
152 RC == ARM::tcGPRRegisterClass) {
154 if (I != MBB.end()) DL = I->getDebugLoc();
156 MachineFunction &MF = *MBB.getParent();
157 MachineFrameInfo &MFI = *MF.getFrameInfo();
158 MachineMemOperand *MMO =
159 MF.getMachineMemOperand(PseudoSourceValue::getFixedStack(FI),
160 MachineMemOperand::MOLoad, 0,
161 MFI.getObjectSize(FI),
162 MFI.getObjectAlignment(FI));
163 AddDefaultPred(BuildMI(MBB, I, DL, get(ARM::t2LDRi12), DestReg)
164 .addFrameIndex(FI).addImm(0).addMemOperand(MMO));
168 ARMBaseInstrInfo::loadRegFromStackSlot(MBB, I, DestReg, FI, RC, TRI);
171 ScheduleHazardRecognizer *Thumb2InstrInfo::
172 CreateTargetPostRAHazardRecognizer(const InstrItineraryData &II) const {
173 return (ScheduleHazardRecognizer *)new Thumb2HazardRecognizer(II);
176 void llvm::emitT2RegPlusImmediate(MachineBasicBlock &MBB,
177 MachineBasicBlock::iterator &MBBI, DebugLoc dl,
178 unsigned DestReg, unsigned BaseReg, int NumBytes,
179 ARMCC::CondCodes Pred, unsigned PredReg,
180 const ARMBaseInstrInfo &TII) {
181 bool isSub = NumBytes < 0;
182 if (isSub) NumBytes = -NumBytes;
184 // If profitable, use a movw or movt to materialize the offset.
185 // FIXME: Use the scavenger to grab a scratch register.
186 if (DestReg != ARM::SP && DestReg != BaseReg &&
188 ARM_AM::getT2SOImmVal(NumBytes) == -1) {
190 if (NumBytes < 65536) {
191 // Use a movw to materialize the 16-bit constant.
192 BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVi16), DestReg)
194 .addImm((unsigned)Pred).addReg(PredReg).addReg(0);
196 } else if ((NumBytes & 0xffff) == 0) {
197 // Use a movt to materialize the 32-bit constant.
198 BuildMI(MBB, MBBI, dl, TII.get(ARM::t2MOVTi16), DestReg)
200 .addImm(NumBytes >> 16)
201 .addImm((unsigned)Pred).addReg(PredReg).addReg(0);
207 BuildMI(MBB, MBBI, dl, TII.get(ARM::t2SUBrr), DestReg)
208 .addReg(BaseReg, RegState::Kill)
209 .addReg(DestReg, RegState::Kill)
210 .addImm((unsigned)Pred).addReg(PredReg).addReg(0);
212 BuildMI(MBB, MBBI, dl, TII.get(ARM::t2ADDrr), DestReg)
213 .addReg(DestReg, RegState::Kill)
214 .addReg(BaseReg, RegState::Kill)
215 .addImm((unsigned)Pred).addReg(PredReg).addReg(0);
222 unsigned ThisVal = NumBytes;
224 if (DestReg == ARM::SP && BaseReg != ARM::SP) {
225 // mov sp, rn. Note t2MOVr cannot be used.
226 BuildMI(MBB, MBBI, dl, TII.get(ARM::tMOVgpr2gpr),DestReg).addReg(BaseReg);
231 bool HasCCOut = true;
232 if (BaseReg == ARM::SP) {
234 if (DestReg == ARM::SP && (ThisVal < ((1 << 7)-1) * 4)) {
235 assert((ThisVal & 3) == 0 && "Stack update is not multiple of 4?");
236 Opc = isSub ? ARM::tSUBspi : ARM::tADDspi;
237 // FIXME: Fix Thumb1 immediate encoding.
238 BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
239 .addReg(BaseReg).addImm(ThisVal/4);
244 // sub rd, sp, so_imm
245 Opc = isSub ? ARM::t2SUBrSPi : ARM::t2ADDrSPi;
246 if (ARM_AM::getT2SOImmVal(NumBytes) != -1) {
249 // FIXME: Move this to ARMAddressingModes.h?
250 unsigned RotAmt = CountLeadingZeros_32(ThisVal);
251 ThisVal = ThisVal & ARM_AM::rotr32(0xff000000U, RotAmt);
252 NumBytes &= ~ThisVal;
253 assert(ARM_AM::getT2SOImmVal(ThisVal) != -1 &&
254 "Bit extraction didn't work?");
257 assert(DestReg != ARM::SP && BaseReg != ARM::SP);
258 Opc = isSub ? ARM::t2SUBri : ARM::t2ADDri;
259 if (ARM_AM::getT2SOImmVal(NumBytes) != -1) {
261 } else if (ThisVal < 4096) {
262 Opc = isSub ? ARM::t2SUBri12 : ARM::t2ADDri12;
266 // FIXME: Move this to ARMAddressingModes.h?
267 unsigned RotAmt = CountLeadingZeros_32(ThisVal);
268 ThisVal = ThisVal & ARM_AM::rotr32(0xff000000U, RotAmt);
269 NumBytes &= ~ThisVal;
270 assert(ARM_AM::getT2SOImmVal(ThisVal) != -1 &&
271 "Bit extraction didn't work?");
275 // Build the new ADD / SUB.
276 MachineInstrBuilder MIB =
277 AddDefaultPred(BuildMI(MBB, MBBI, dl, TII.get(Opc), DestReg)
278 .addReg(BaseReg, RegState::Kill)
288 negativeOffsetOpcode(unsigned opcode)
291 case ARM::t2LDRi12: return ARM::t2LDRi8;
292 case ARM::t2LDRHi12: return ARM::t2LDRHi8;
293 case ARM::t2LDRBi12: return ARM::t2LDRBi8;
294 case ARM::t2LDRSHi12: return ARM::t2LDRSHi8;
295 case ARM::t2LDRSBi12: return ARM::t2LDRSBi8;
296 case ARM::t2STRi12: return ARM::t2STRi8;
297 case ARM::t2STRBi12: return ARM::t2STRBi8;
298 case ARM::t2STRHi12: return ARM::t2STRHi8;
318 positiveOffsetOpcode(unsigned opcode)
321 case ARM::t2LDRi8: return ARM::t2LDRi12;
322 case ARM::t2LDRHi8: return ARM::t2LDRHi12;
323 case ARM::t2LDRBi8: return ARM::t2LDRBi12;
324 case ARM::t2LDRSHi8: return ARM::t2LDRSHi12;
325 case ARM::t2LDRSBi8: return ARM::t2LDRSBi12;
326 case ARM::t2STRi8: return ARM::t2STRi12;
327 case ARM::t2STRBi8: return ARM::t2STRBi12;
328 case ARM::t2STRHi8: return ARM::t2STRHi12;
333 case ARM::t2LDRSHi12:
334 case ARM::t2LDRSBi12:
348 immediateOffsetOpcode(unsigned opcode)
351 case ARM::t2LDRs: return ARM::t2LDRi12;
352 case ARM::t2LDRHs: return ARM::t2LDRHi12;
353 case ARM::t2LDRBs: return ARM::t2LDRBi12;
354 case ARM::t2LDRSHs: return ARM::t2LDRSHi12;
355 case ARM::t2LDRSBs: return ARM::t2LDRSBi12;
356 case ARM::t2STRs: return ARM::t2STRi12;
357 case ARM::t2STRBs: return ARM::t2STRBi12;
358 case ARM::t2STRHs: return ARM::t2STRHi12;
363 case ARM::t2LDRSHi12:
364 case ARM::t2LDRSBi12:
385 bool llvm::rewriteT2FrameIndex(MachineInstr &MI, unsigned FrameRegIdx,
386 unsigned FrameReg, int &Offset,
387 const ARMBaseInstrInfo &TII) {
388 unsigned Opcode = MI.getOpcode();
389 const TargetInstrDesc &Desc = MI.getDesc();
390 unsigned AddrMode = (Desc.TSFlags & ARMII::AddrModeMask);
393 // Memory operands in inline assembly always use AddrModeT2_i12.
394 if (Opcode == ARM::INLINEASM)
395 AddrMode = ARMII::AddrModeT2_i12; // FIXME. mode for thumb2?
397 if (Opcode == ARM::t2ADDri || Opcode == ARM::t2ADDri12) {
398 Offset += MI.getOperand(FrameRegIdx+1).getImm();
401 if (Offset == 0 && getInstrPredicate(&MI, PredReg) == ARMCC::AL) {
402 // Turn it into a move.
403 MI.setDesc(TII.get(ARM::tMOVgpr2gpr));
404 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
405 // Remove offset and remaining explicit predicate operands.
406 do MI.RemoveOperand(FrameRegIdx+1);
407 while (MI.getNumOperands() > FrameRegIdx+1 &&
408 (!MI.getOperand(FrameRegIdx+1).isReg() ||
409 !MI.getOperand(FrameRegIdx+1).isImm()));
413 bool isSP = FrameReg == ARM::SP;
414 bool HasCCOut = Opcode != ARM::t2ADDri12;
419 MI.setDesc(TII.get(isSP ? ARM::t2SUBrSPi : ARM::t2SUBri));
421 MI.setDesc(TII.get(isSP ? ARM::t2ADDrSPi : ARM::t2ADDri));
424 // Common case: small offset, fits into instruction.
425 if (ARM_AM::getT2SOImmVal(Offset) != -1) {
426 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
427 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
428 // Add cc_out operand if the original instruction did not have one.
430 MI.addOperand(MachineOperand::CreateReg(0, false));
434 // Another common case: imm12.
436 (!HasCCOut || MI.getOperand(MI.getNumOperands()-1).getReg() == 0)) {
437 unsigned NewOpc = isSP
438 ? (isSub ? ARM::t2SUBrSPi12 : ARM::t2ADDrSPi12)
439 : (isSub ? ARM::t2SUBri12 : ARM::t2ADDri12);
440 MI.setDesc(TII.get(NewOpc));
441 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
442 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(Offset);
443 // Remove the cc_out operand.
445 MI.RemoveOperand(MI.getNumOperands()-1);
450 // Otherwise, extract 8 adjacent bits from the immediate into this
452 unsigned RotAmt = CountLeadingZeros_32(Offset);
453 unsigned ThisImmVal = Offset & ARM_AM::rotr32(0xff000000U, RotAmt);
455 // We will handle these bits from offset, clear them.
456 Offset &= ~ThisImmVal;
458 assert(ARM_AM::getT2SOImmVal(ThisImmVal) != -1 &&
459 "Bit extraction didn't work?");
460 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(ThisImmVal);
461 // Add cc_out operand if the original instruction did not have one.
463 MI.addOperand(MachineOperand::CreateReg(0, false));
467 // AddrMode4 and AddrMode6 cannot handle any offset.
468 if (AddrMode == ARMII::AddrMode4 || AddrMode == ARMII::AddrMode6)
471 // AddrModeT2_so cannot handle any offset. If there is no offset
472 // register then we change to an immediate version.
473 unsigned NewOpc = Opcode;
474 if (AddrMode == ARMII::AddrModeT2_so) {
475 unsigned OffsetReg = MI.getOperand(FrameRegIdx+1).getReg();
476 if (OffsetReg != 0) {
477 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
481 MI.RemoveOperand(FrameRegIdx+1);
482 MI.getOperand(FrameRegIdx+1).ChangeToImmediate(0);
483 NewOpc = immediateOffsetOpcode(Opcode);
484 AddrMode = ARMII::AddrModeT2_i12;
487 unsigned NumBits = 0;
489 if (AddrMode == ARMII::AddrModeT2_i8 || AddrMode == ARMII::AddrModeT2_i12) {
490 // i8 supports only negative, and i12 supports only positive, so
491 // based on Offset sign convert Opcode to the appropriate
493 Offset += MI.getOperand(FrameRegIdx+1).getImm();
495 NewOpc = negativeOffsetOpcode(Opcode);
500 NewOpc = positiveOffsetOpcode(Opcode);
503 } else if (AddrMode == ARMII::AddrMode5) {
505 const MachineOperand &OffOp = MI.getOperand(FrameRegIdx+1);
506 int InstrOffs = ARM_AM::getAM5Offset(OffOp.getImm());
507 if (ARM_AM::getAM5Op(OffOp.getImm()) == ARM_AM::sub)
511 Offset += InstrOffs * 4;
512 assert((Offset & (Scale-1)) == 0 && "Can't encode this offset!");
518 llvm_unreachable("Unsupported addressing mode!");
521 if (NewOpc != Opcode)
522 MI.setDesc(TII.get(NewOpc));
524 MachineOperand &ImmOp = MI.getOperand(FrameRegIdx+1);
526 // Attempt to fold address computation
527 // Common case: small offset, fits into instruction.
528 int ImmedOffset = Offset / Scale;
529 unsigned Mask = (1 << NumBits) - 1;
530 if ((unsigned)Offset <= Mask * Scale) {
531 // Replace the FrameIndex with fp/sp
532 MI.getOperand(FrameRegIdx).ChangeToRegister(FrameReg, false);
534 if (AddrMode == ARMII::AddrMode5)
535 // FIXME: Not consistent.
536 ImmedOffset |= 1 << NumBits;
538 ImmedOffset = -ImmedOffset;
540 ImmOp.ChangeToImmediate(ImmedOffset);
545 // Otherwise, offset doesn't fit. Pull in what we can to simplify
546 ImmedOffset = ImmedOffset & Mask;
548 if (AddrMode == ARMII::AddrMode5)
549 // FIXME: Not consistent.
550 ImmedOffset |= 1 << NumBits;
552 ImmedOffset = -ImmedOffset;
553 if (ImmedOffset == 0)
554 // Change the opcode back if the encoded offset is zero.
555 MI.setDesc(TII.get(positiveOffsetOpcode(NewOpc)));
558 ImmOp.ChangeToImmediate(ImmedOffset);
559 Offset &= ~(Mask*Scale);
562 Offset = (isSub) ? -Offset : Offset;
566 /// scheduleTwoAddrSource - Schedule the copy / re-mat of the source of the
567 /// two-addrss instruction inserted by two-address pass.
569 Thumb2InstrInfo::scheduleTwoAddrSource(MachineInstr *SrcMI,
571 const TargetRegisterInfo &TRI) const {
572 if (SrcMI->getOpcode() != ARM::tMOVgpr2gpr ||
573 SrcMI->getOperand(1).isKill())
576 unsigned PredReg = 0;
577 ARMCC::CondCodes CC = llvm::getInstrPredicate(UseMI, PredReg);
578 if (CC == ARMCC::AL || PredReg != ARM::CPSR)
581 // Schedule the copy so it doesn't come between previous instructions
582 // and UseMI which can form an IT block.
583 unsigned SrcReg = SrcMI->getOperand(1).getReg();
584 ARMCC::CondCodes OCC = ARMCC::getOppositeCondition(CC);
585 MachineBasicBlock *MBB = UseMI->getParent();
586 MachineBasicBlock::iterator MBBI = SrcMI;
587 unsigned NumInsts = 0;
588 while (--MBBI != MBB->begin()) {
589 if (MBBI->isDebugValue())
592 MachineInstr *NMI = &*MBBI;
593 ARMCC::CondCodes NCC = llvm::getInstrPredicate(NMI, PredReg);
594 if (!(NCC == CC || NCC == OCC) ||
595 NMI->modifiesRegister(SrcReg, &TRI) ||
596 NMI->definesRegister(ARM::CPSR))
599 // Too many in a row!
605 MBB->insert(++MBBI, SrcMI);