1 //===-- MipsSEFrameLowering.cpp - Mips32/64 Frame Information -------------===//
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 Mips32/64 implementation of TargetFrameLowering class.
12 //===----------------------------------------------------------------------===//
14 #include "MCTargetDesc/MipsABIInfo.h"
15 #include "MipsMachineFunction.h"
16 #include "MipsRegisterInfo.h"
17 #include "MipsSEFrameLowering.h"
18 #include "MipsSEInstrInfo.h"
19 #include "MipsSubtarget.h"
20 #include "llvm/ADT/BitVector.h"
21 #include "llvm/ADT/StringRef.h"
22 #include "llvm/ADT/StringSwitch.h"
23 #include "llvm/CodeGen/MachineBasicBlock.h"
24 #include "llvm/CodeGen/MachineFrameInfo.h"
25 #include "llvm/CodeGen/MachineFunction.h"
26 #include "llvm/CodeGen/MachineInstr.h"
27 #include "llvm/CodeGen/MachineInstrBuilder.h"
28 #include "llvm/CodeGen/MachineModuleInfo.h"
29 #include "llvm/CodeGen/MachineOperand.h"
30 #include "llvm/CodeGen/MachineRegisterInfo.h"
31 #include "llvm/CodeGen/RegisterScavenging.h"
32 #include "llvm/IR/DebugLoc.h"
33 #include "llvm/IR/Function.h"
34 #include "llvm/MC/MCDwarf.h"
35 #include "llvm/MC/MCRegisterInfo.h"
36 #include "llvm/MC/MachineLocation.h"
37 #include "llvm/Support/CodeGen.h"
38 #include "llvm/Support/ErrorHandling.h"
39 #include "llvm/Support/MathExtras.h"
40 #include "llvm/Target/TargetInstrInfo.h"
41 #include "llvm/Target/TargetRegisterInfo.h"
42 #include "llvm/Target/TargetSubtargetInfo.h"
50 static std::pair<unsigned, unsigned> getMFHiLoOpc(unsigned Src) {
51 if (Mips::ACC64RegClass.contains(Src))
52 return std::make_pair((unsigned)Mips::PseudoMFHI,
53 (unsigned)Mips::PseudoMFLO);
55 if (Mips::ACC64DSPRegClass.contains(Src))
56 return std::make_pair((unsigned)Mips::MFHI_DSP, (unsigned)Mips::MFLO_DSP);
58 if (Mips::ACC128RegClass.contains(Src))
59 return std::make_pair((unsigned)Mips::PseudoMFHI64,
60 (unsigned)Mips::PseudoMFLO64);
62 return std::make_pair(0, 0);
67 /// Helper class to expand pseudos.
70 ExpandPseudo(MachineFunction &MF);
74 typedef MachineBasicBlock::iterator Iter;
76 bool expandInstr(MachineBasicBlock &MBB, Iter I);
77 void expandLoadCCond(MachineBasicBlock &MBB, Iter I);
78 void expandStoreCCond(MachineBasicBlock &MBB, Iter I);
79 void expandLoadACC(MachineBasicBlock &MBB, Iter I, unsigned RegSize);
80 void expandStoreACC(MachineBasicBlock &MBB, Iter I, unsigned MFHiOpc,
81 unsigned MFLoOpc, unsigned RegSize);
82 bool expandCopy(MachineBasicBlock &MBB, Iter I);
83 bool expandCopyACC(MachineBasicBlock &MBB, Iter I, unsigned MFHiOpc,
85 bool expandBuildPairF64(MachineBasicBlock &MBB,
86 MachineBasicBlock::iterator I, bool FP64) const;
87 bool expandExtractElementF64(MachineBasicBlock &MBB,
88 MachineBasicBlock::iterator I, bool FP64) const;
91 MachineRegisterInfo &MRI;
92 const MipsSubtarget &Subtarget;
93 const MipsSEInstrInfo &TII;
94 const MipsRegisterInfo &RegInfo;
97 } // end anonymous namespace
99 ExpandPseudo::ExpandPseudo(MachineFunction &MF_)
100 : MF(MF_), MRI(MF.getRegInfo()),
101 Subtarget(static_cast<const MipsSubtarget &>(MF.getSubtarget())),
102 TII(*static_cast<const MipsSEInstrInfo *>(Subtarget.getInstrInfo())),
103 RegInfo(*Subtarget.getRegisterInfo()) {}
105 bool ExpandPseudo::expand() {
106 bool Expanded = false;
108 for (auto &MBB : MF) {
109 for (Iter I = MBB.begin(), End = MBB.end(); I != End;)
110 Expanded |= expandInstr(MBB, I++);
116 bool ExpandPseudo::expandInstr(MachineBasicBlock &MBB, Iter I) {
117 switch(I->getOpcode()) {
118 case Mips::LOAD_CCOND_DSP:
119 expandLoadCCond(MBB, I);
121 case Mips::STORE_CCOND_DSP:
122 expandStoreCCond(MBB, I);
124 case Mips::LOAD_ACC64:
125 case Mips::LOAD_ACC64DSP:
126 expandLoadACC(MBB, I, 4);
128 case Mips::LOAD_ACC128:
129 expandLoadACC(MBB, I, 8);
131 case Mips::STORE_ACC64:
132 expandStoreACC(MBB, I, Mips::PseudoMFHI, Mips::PseudoMFLO, 4);
134 case Mips::STORE_ACC64DSP:
135 expandStoreACC(MBB, I, Mips::MFHI_DSP, Mips::MFLO_DSP, 4);
137 case Mips::STORE_ACC128:
138 expandStoreACC(MBB, I, Mips::PseudoMFHI64, Mips::PseudoMFLO64, 8);
140 case Mips::BuildPairF64:
141 if (expandBuildPairF64(MBB, I, false))
144 case Mips::BuildPairF64_64:
145 if (expandBuildPairF64(MBB, I, true))
148 case Mips::ExtractElementF64:
149 if (expandExtractElementF64(MBB, I, false))
152 case Mips::ExtractElementF64_64:
153 if (expandExtractElementF64(MBB, I, true))
156 case TargetOpcode::COPY:
157 if (!expandCopy(MBB, I))
168 void ExpandPseudo::expandLoadCCond(MachineBasicBlock &MBB, Iter I) {
172 assert(I->getOperand(0).isReg() && I->getOperand(1).isFI());
174 const TargetRegisterClass *RC = RegInfo.intRegClass(4);
175 unsigned VR = MRI.createVirtualRegister(RC);
176 unsigned Dst = I->getOperand(0).getReg(), FI = I->getOperand(1).getIndex();
178 TII.loadRegFromStack(MBB, I, VR, FI, RC, &RegInfo, 0);
179 BuildMI(MBB, I, I->getDebugLoc(), TII.get(TargetOpcode::COPY), Dst)
180 .addReg(VR, RegState::Kill);
183 void ExpandPseudo::expandStoreCCond(MachineBasicBlock &MBB, Iter I) {
187 assert(I->getOperand(0).isReg() && I->getOperand(1).isFI());
189 const TargetRegisterClass *RC = RegInfo.intRegClass(4);
190 unsigned VR = MRI.createVirtualRegister(RC);
191 unsigned Src = I->getOperand(0).getReg(), FI = I->getOperand(1).getIndex();
193 BuildMI(MBB, I, I->getDebugLoc(), TII.get(TargetOpcode::COPY), VR)
194 .addReg(Src, getKillRegState(I->getOperand(0).isKill()));
195 TII.storeRegToStack(MBB, I, VR, true, FI, RC, &RegInfo, 0);
198 void ExpandPseudo::expandLoadACC(MachineBasicBlock &MBB, Iter I,
205 assert(I->getOperand(0).isReg() && I->getOperand(1).isFI());
207 const TargetRegisterClass *RC = RegInfo.intRegClass(RegSize);
208 unsigned VR0 = MRI.createVirtualRegister(RC);
209 unsigned VR1 = MRI.createVirtualRegister(RC);
210 unsigned Dst = I->getOperand(0).getReg(), FI = I->getOperand(1).getIndex();
211 unsigned Lo = RegInfo.getSubReg(Dst, Mips::sub_lo);
212 unsigned Hi = RegInfo.getSubReg(Dst, Mips::sub_hi);
213 DebugLoc DL = I->getDebugLoc();
214 const MCInstrDesc &Desc = TII.get(TargetOpcode::COPY);
216 TII.loadRegFromStack(MBB, I, VR0, FI, RC, &RegInfo, 0);
217 BuildMI(MBB, I, DL, Desc, Lo).addReg(VR0, RegState::Kill);
218 TII.loadRegFromStack(MBB, I, VR1, FI, RC, &RegInfo, RegSize);
219 BuildMI(MBB, I, DL, Desc, Hi).addReg(VR1, RegState::Kill);
222 void ExpandPseudo::expandStoreACC(MachineBasicBlock &MBB, Iter I,
223 unsigned MFHiOpc, unsigned MFLoOpc,
228 // store $vr1, FI + 4
230 assert(I->getOperand(0).isReg() && I->getOperand(1).isFI());
232 const TargetRegisterClass *RC = RegInfo.intRegClass(RegSize);
233 unsigned VR0 = MRI.createVirtualRegister(RC);
234 unsigned VR1 = MRI.createVirtualRegister(RC);
235 unsigned Src = I->getOperand(0).getReg(), FI = I->getOperand(1).getIndex();
236 unsigned SrcKill = getKillRegState(I->getOperand(0).isKill());
237 DebugLoc DL = I->getDebugLoc();
239 BuildMI(MBB, I, DL, TII.get(MFLoOpc), VR0).addReg(Src);
240 TII.storeRegToStack(MBB, I, VR0, true, FI, RC, &RegInfo, 0);
241 BuildMI(MBB, I, DL, TII.get(MFHiOpc), VR1).addReg(Src, SrcKill);
242 TII.storeRegToStack(MBB, I, VR1, true, FI, RC, &RegInfo, RegSize);
245 bool ExpandPseudo::expandCopy(MachineBasicBlock &MBB, Iter I) {
246 unsigned Src = I->getOperand(1).getReg();
247 std::pair<unsigned, unsigned> Opcodes = getMFHiLoOpc(Src);
252 return expandCopyACC(MBB, I, Opcodes.first, Opcodes.second);
255 bool ExpandPseudo::expandCopyACC(MachineBasicBlock &MBB, Iter I,
256 unsigned MFHiOpc, unsigned MFLoOpc) {
262 unsigned Dst = I->getOperand(0).getReg(), Src = I->getOperand(1).getReg();
263 const TargetRegisterClass *DstRC = RegInfo.getMinimalPhysRegClass(Dst);
264 unsigned VRegSize = RegInfo.getRegSizeInBits(*DstRC) / 16;
265 const TargetRegisterClass *RC = RegInfo.intRegClass(VRegSize);
266 unsigned VR0 = MRI.createVirtualRegister(RC);
267 unsigned VR1 = MRI.createVirtualRegister(RC);
268 unsigned SrcKill = getKillRegState(I->getOperand(1).isKill());
269 unsigned DstLo = RegInfo.getSubReg(Dst, Mips::sub_lo);
270 unsigned DstHi = RegInfo.getSubReg(Dst, Mips::sub_hi);
271 DebugLoc DL = I->getDebugLoc();
273 BuildMI(MBB, I, DL, TII.get(MFLoOpc), VR0).addReg(Src);
274 BuildMI(MBB, I, DL, TII.get(TargetOpcode::COPY), DstLo)
275 .addReg(VR0, RegState::Kill);
276 BuildMI(MBB, I, DL, TII.get(MFHiOpc), VR1).addReg(Src, SrcKill);
277 BuildMI(MBB, I, DL, TII.get(TargetOpcode::COPY), DstHi)
278 .addReg(VR1, RegState::Kill);
282 /// This method expands the same instruction that MipsSEInstrInfo::
283 /// expandBuildPairF64 does, for the case when ABI is fpxx and mthc1 is not
284 /// available and the case where the ABI is FP64A. It is implemented here
285 /// because frame indexes are eliminated before MipsSEInstrInfo::
286 /// expandBuildPairF64 is called.
287 bool ExpandPseudo::expandBuildPairF64(MachineBasicBlock &MBB,
288 MachineBasicBlock::iterator I,
290 // For fpxx and when mthc1 is not available, use:
291 // spill + reload via ldc1
293 // The case where dmtc1 is available doesn't need to be handled here
294 // because it never creates a BuildPairF64 node.
296 // The FP64A ABI (fp64 with nooddspreg) must also use a spill/reload sequence
297 // for odd-numbered double precision values (because the lower 32-bits is
298 // transferred with mtc1 which is redirected to the upper half of the even
299 // register). Unfortunately, we have to make this decision before register
300 // allocation so for now we use a spill/reload sequence for all
301 // double-precision values in regardless of being an odd/even register.
302 if ((Subtarget.isABI_FPXX() && !Subtarget.hasMTHC1()) ||
303 (FP64 && !Subtarget.useOddSPReg())) {
304 unsigned DstReg = I->getOperand(0).getReg();
305 unsigned LoReg = I->getOperand(1).getReg();
306 unsigned HiReg = I->getOperand(2).getReg();
308 // It should be impossible to have FGR64 on MIPS-II or MIPS32r1 (which are
309 // the cases where mthc1 is not available). 64-bit architectures and
310 // MIPS32r2 or later can use FGR64 though.
311 assert(Subtarget.isGP64bit() || Subtarget.hasMTHC1() ||
312 !Subtarget.isFP64bit());
314 const TargetRegisterClass *RC = &Mips::GPR32RegClass;
315 const TargetRegisterClass *RC2 =
316 FP64 ? &Mips::FGR64RegClass : &Mips::AFGR64RegClass;
318 // We re-use the same spill slot each time so that the stack frame doesn't
319 // grow too much in functions with a large number of moves.
320 int FI = MF.getInfo<MipsFunctionInfo>()->getMoveF64ViaSpillFI(RC2);
321 if (!Subtarget.isLittle())
322 std::swap(LoReg, HiReg);
323 TII.storeRegToStack(MBB, I, LoReg, I->getOperand(1).isKill(), FI, RC,
325 TII.storeRegToStack(MBB, I, HiReg, I->getOperand(2).isKill(), FI, RC,
327 TII.loadRegFromStack(MBB, I, DstReg, FI, RC2, &RegInfo, 0);
334 /// This method expands the same instruction that MipsSEInstrInfo::
335 /// expandExtractElementF64 does, for the case when ABI is fpxx and mfhc1 is not
336 /// available and the case where the ABI is FP64A. It is implemented here
337 /// because frame indexes are eliminated before MipsSEInstrInfo::
338 /// expandExtractElementF64 is called.
339 bool ExpandPseudo::expandExtractElementF64(MachineBasicBlock &MBB,
340 MachineBasicBlock::iterator I,
342 const MachineOperand &Op1 = I->getOperand(1);
343 const MachineOperand &Op2 = I->getOperand(2);
345 if ((Op1.isReg() && Op1.isUndef()) || (Op2.isReg() && Op2.isUndef())) {
346 unsigned DstReg = I->getOperand(0).getReg();
347 BuildMI(MBB, I, I->getDebugLoc(), TII.get(Mips::IMPLICIT_DEF), DstReg);
351 // For fpxx and when mfhc1 is not available, use:
352 // spill + reload via ldc1
354 // The case where dmfc1 is available doesn't need to be handled here
355 // because it never creates a ExtractElementF64 node.
357 // The FP64A ABI (fp64 with nooddspreg) must also use a spill/reload sequence
358 // for odd-numbered double precision values (because the lower 32-bits is
359 // transferred with mfc1 which is redirected to the upper half of the even
360 // register). Unfortunately, we have to make this decision before register
361 // allocation so for now we use a spill/reload sequence for all
362 // double-precision values in regardless of being an odd/even register.
364 if ((Subtarget.isABI_FPXX() && !Subtarget.hasMTHC1()) ||
365 (FP64 && !Subtarget.useOddSPReg())) {
366 unsigned DstReg = I->getOperand(0).getReg();
367 unsigned SrcReg = Op1.getReg();
368 unsigned N = Op2.getImm();
369 int64_t Offset = 4 * (Subtarget.isLittle() ? N : (1 - N));
371 // It should be impossible to have FGR64 on MIPS-II or MIPS32r1 (which are
372 // the cases where mfhc1 is not available). 64-bit architectures and
373 // MIPS32r2 or later can use FGR64 though.
374 assert(Subtarget.isGP64bit() || Subtarget.hasMTHC1() ||
375 !Subtarget.isFP64bit());
377 const TargetRegisterClass *RC =
378 FP64 ? &Mips::FGR64RegClass : &Mips::AFGR64RegClass;
379 const TargetRegisterClass *RC2 = &Mips::GPR32RegClass;
381 // We re-use the same spill slot each time so that the stack frame doesn't
382 // grow too much in functions with a large number of moves.
383 int FI = MF.getInfo<MipsFunctionInfo>()->getMoveF64ViaSpillFI(RC);
384 TII.storeRegToStack(MBB, I, SrcReg, Op1.isKill(), FI, RC, &RegInfo, 0);
385 TII.loadRegFromStack(MBB, I, DstReg, FI, RC2, &RegInfo, Offset);
392 MipsSEFrameLowering::MipsSEFrameLowering(const MipsSubtarget &STI)
393 : MipsFrameLowering(STI, STI.stackAlignment()) {}
395 void MipsSEFrameLowering::emitPrologue(MachineFunction &MF,
396 MachineBasicBlock &MBB) const {
397 assert(&MF.front() == &MBB && "Shrink-wrapping not yet supported");
398 MachineFrameInfo &MFI = MF.getFrameInfo();
399 MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
401 const MipsSEInstrInfo &TII =
402 *static_cast<const MipsSEInstrInfo *>(STI.getInstrInfo());
403 const MipsRegisterInfo &RegInfo =
404 *static_cast<const MipsRegisterInfo *>(STI.getRegisterInfo());
406 MachineBasicBlock::iterator MBBI = MBB.begin();
408 MipsABIInfo ABI = STI.getABI();
409 unsigned SP = ABI.GetStackPtr();
410 unsigned FP = ABI.GetFramePtr();
411 unsigned ZERO = ABI.GetNullPtr();
412 unsigned MOVE = ABI.GetGPRMoveOp();
413 unsigned ADDiu = ABI.GetPtrAddiuOp();
414 unsigned AND = ABI.IsN64() ? Mips::AND64 : Mips::AND;
416 const TargetRegisterClass *RC = ABI.ArePtrs64bit() ?
417 &Mips::GPR64RegClass : &Mips::GPR32RegClass;
419 // First, compute final stack size.
420 uint64_t StackSize = MFI.getStackSize();
422 // No need to allocate space on the stack.
423 if (StackSize == 0 && !MFI.adjustsStack()) return;
425 MachineModuleInfo &MMI = MF.getMMI();
426 const MCRegisterInfo *MRI = MMI.getContext().getRegisterInfo();
427 MachineLocation DstML, SrcML;
430 TII.adjustStackPtr(SP, -StackSize, MBB, MBBI);
432 // emit ".cfi_def_cfa_offset StackSize"
433 unsigned CFIIndex = MF.addFrameInst(
434 MCCFIInstruction::createDefCfaOffset(nullptr, -StackSize));
435 BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
436 .addCFIIndex(CFIIndex);
438 if (MF.getFunction()->hasFnAttribute("interrupt"))
439 emitInterruptPrologueStub(MF, MBB);
441 const std::vector<CalleeSavedInfo> &CSI = MFI.getCalleeSavedInfo();
444 // Find the instruction past the last instruction that saves a callee-saved
445 // register to the stack.
446 for (unsigned i = 0; i < CSI.size(); ++i)
449 // Iterate over list of callee-saved registers and emit .cfi_offset
451 for (std::vector<CalleeSavedInfo>::const_iterator I = CSI.begin(),
452 E = CSI.end(); I != E; ++I) {
453 int64_t Offset = MFI.getObjectOffset(I->getFrameIdx());
454 unsigned Reg = I->getReg();
456 // If Reg is a double precision register, emit two cfa_offsets,
457 // one for each of the paired single precision registers.
458 if (Mips::AFGR64RegClass.contains(Reg)) {
460 MRI->getDwarfRegNum(RegInfo.getSubReg(Reg, Mips::sub_lo), true);
462 MRI->getDwarfRegNum(RegInfo.getSubReg(Reg, Mips::sub_hi), true);
465 std::swap(Reg0, Reg1);
467 unsigned CFIIndex = MF.addFrameInst(
468 MCCFIInstruction::createOffset(nullptr, Reg0, Offset));
469 BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
470 .addCFIIndex(CFIIndex);
472 CFIIndex = MF.addFrameInst(
473 MCCFIInstruction::createOffset(nullptr, Reg1, Offset + 4));
474 BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
475 .addCFIIndex(CFIIndex);
476 } else if (Mips::FGR64RegClass.contains(Reg)) {
477 unsigned Reg0 = MRI->getDwarfRegNum(Reg, true);
478 unsigned Reg1 = MRI->getDwarfRegNum(Reg, true) + 1;
481 std::swap(Reg0, Reg1);
483 unsigned CFIIndex = MF.addFrameInst(
484 MCCFIInstruction::createOffset(nullptr, Reg0, Offset));
485 BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
486 .addCFIIndex(CFIIndex);
488 CFIIndex = MF.addFrameInst(
489 MCCFIInstruction::createOffset(nullptr, Reg1, Offset + 4));
490 BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
491 .addCFIIndex(CFIIndex);
493 // Reg is either in GPR32 or FGR32.
494 unsigned CFIIndex = MF.addFrameInst(MCCFIInstruction::createOffset(
495 nullptr, MRI->getDwarfRegNum(Reg, true), Offset));
496 BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
497 .addCFIIndex(CFIIndex);
502 if (MipsFI->callsEhReturn()) {
503 // Insert instructions that spill eh data registers.
504 for (int I = 0; I < 4; ++I) {
505 if (!MBB.isLiveIn(ABI.GetEhDataReg(I)))
506 MBB.addLiveIn(ABI.GetEhDataReg(I));
507 TII.storeRegToStackSlot(MBB, MBBI, ABI.GetEhDataReg(I), false,
508 MipsFI->getEhDataRegFI(I), RC, &RegInfo);
511 // Emit .cfi_offset directives for eh data registers.
512 for (int I = 0; I < 4; ++I) {
513 int64_t Offset = MFI.getObjectOffset(MipsFI->getEhDataRegFI(I));
514 unsigned Reg = MRI->getDwarfRegNum(ABI.GetEhDataReg(I), true);
515 unsigned CFIIndex = MF.addFrameInst(
516 MCCFIInstruction::createOffset(nullptr, Reg, Offset));
517 BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
518 .addCFIIndex(CFIIndex);
522 // if framepointer enabled, set it to point to the stack pointer.
524 // Insert instruction "move $fp, $sp" at this location.
525 BuildMI(MBB, MBBI, dl, TII.get(MOVE), FP).addReg(SP).addReg(ZERO)
526 .setMIFlag(MachineInstr::FrameSetup);
528 // emit ".cfi_def_cfa_register $fp"
529 unsigned CFIIndex = MF.addFrameInst(MCCFIInstruction::createDefCfaRegister(
530 nullptr, MRI->getDwarfRegNum(FP, true)));
531 BuildMI(MBB, MBBI, dl, TII.get(TargetOpcode::CFI_INSTRUCTION))
532 .addCFIIndex(CFIIndex);
534 if (RegInfo.needsStackRealignment(MF)) {
535 // addiu $Reg, $zero, -MaxAlignment
536 // andi $sp, $sp, $Reg
537 unsigned VR = MF.getRegInfo().createVirtualRegister(RC);
538 assert(isInt<16>(MFI.getMaxAlignment()) &&
539 "Function's alignment size requirement is not supported.");
540 int MaxAlign = -(int)MFI.getMaxAlignment();
542 BuildMI(MBB, MBBI, dl, TII.get(ADDiu), VR).addReg(ZERO) .addImm(MaxAlign);
543 BuildMI(MBB, MBBI, dl, TII.get(AND), SP).addReg(SP).addReg(VR);
547 unsigned BP = STI.isABI_N64() ? Mips::S7_64 : Mips::S7;
548 BuildMI(MBB, MBBI, dl, TII.get(MOVE), BP)
556 void MipsSEFrameLowering::emitInterruptPrologueStub(
557 MachineFunction &MF, MachineBasicBlock &MBB) const {
558 MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
559 MachineBasicBlock::iterator MBBI = MBB.begin();
560 DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
562 // Report an error the target doesn't support Mips32r2 or later.
563 // The epilogue relies on the use of the "ehb" to clear execution
564 // hazards. Pre R2 Mips relies on an implementation defined number
565 // of "ssnop"s to clear the execution hazard. Support for ssnop hazard
566 // clearing is not provided so reject that configuration.
567 if (!STI.hasMips32r2())
569 "\"interrupt\" attribute is not supported on pre-MIPS32R2 or "
572 // The GP register contains the "user" value, so we cannot perform
573 // any gp relative loads until we restore the "kernel" or "system" gp
574 // value. Until support is written we shall only accept the static
576 if ((STI.getRelocationModel() != Reloc::Static))
577 report_fatal_error("\"interrupt\" attribute is only supported for the "
578 "static relocation model on MIPS at the present time.");
580 if (!STI.isABI_O32() || STI.hasMips64())
581 report_fatal_error("\"interrupt\" attribute is only supported for the "
582 "O32 ABI on MIPS32R2+ at the present time.");
584 // Perform ISR handling like GCC
586 MF.getFunction()->getFnAttribute("interrupt").getValueAsString();
587 const TargetRegisterClass *PtrRC = &Mips::GPR32RegClass;
589 // EIC interrupt handling needs to read the Cause register to disable
591 if (IntKind == "eic") {
592 // Coprocessor registers are always live per se.
593 MBB.addLiveIn(Mips::COP013);
594 BuildMI(MBB, MBBI, DL, STI.getInstrInfo()->get(Mips::MFC0), Mips::K0)
595 .addReg(Mips::COP013)
597 .setMIFlag(MachineInstr::FrameSetup);
599 BuildMI(MBB, MBBI, DL, STI.getInstrInfo()->get(Mips::EXT), Mips::K0)
603 .setMIFlag(MachineInstr::FrameSetup);
606 // Fetch and spill EPC
607 MBB.addLiveIn(Mips::COP014);
608 BuildMI(MBB, MBBI, DL, STI.getInstrInfo()->get(Mips::MFC0), Mips::K1)
609 .addReg(Mips::COP014)
611 .setMIFlag(MachineInstr::FrameSetup);
613 STI.getInstrInfo()->storeRegToStack(MBB, MBBI, Mips::K1, false,
614 MipsFI->getISRRegFI(0), PtrRC,
615 STI.getRegisterInfo(), 0);
617 // Fetch and Spill Status
618 MBB.addLiveIn(Mips::COP012);
619 BuildMI(MBB, MBBI, DL, STI.getInstrInfo()->get(Mips::MFC0), Mips::K1)
620 .addReg(Mips::COP012)
622 .setMIFlag(MachineInstr::FrameSetup);
624 STI.getInstrInfo()->storeRegToStack(MBB, MBBI, Mips::K1, false,
625 MipsFI->getISRRegFI(1), PtrRC,
626 STI.getRegisterInfo(), 0);
628 // Build the configuration for disabling lower priority interrupts. Non EIC
629 // interrupts need to be masked off with zero, EIC from the Cause register.
630 unsigned InsPosition = 8;
631 unsigned InsSize = 0;
632 unsigned SrcReg = Mips::ZERO;
634 // If the interrupt we're tied to is the EIC, switch the source for the
635 // masking off interrupts to the cause register.
636 if (IntKind == "eic") {
641 InsSize = StringSwitch<unsigned>(IntKind)
651 assert(InsSize != 0 && "Unknown interrupt type!");
653 BuildMI(MBB, MBBI, DL, STI.getInstrInfo()->get(Mips::INS), Mips::K1)
658 .setMIFlag(MachineInstr::FrameSetup);
660 // Mask off KSU, ERL, EXL
661 BuildMI(MBB, MBBI, DL, STI.getInstrInfo()->get(Mips::INS), Mips::K1)
666 .setMIFlag(MachineInstr::FrameSetup);
668 // Disable the FPU as we are not spilling those register sets.
669 if (!STI.useSoftFloat())
670 BuildMI(MBB, MBBI, DL, STI.getInstrInfo()->get(Mips::INS), Mips::K1)
675 .setMIFlag(MachineInstr::FrameSetup);
677 // Set the new status
678 BuildMI(MBB, MBBI, DL, STI.getInstrInfo()->get(Mips::MTC0), Mips::COP012)
681 .setMIFlag(MachineInstr::FrameSetup);
684 void MipsSEFrameLowering::emitEpilogue(MachineFunction &MF,
685 MachineBasicBlock &MBB) const {
686 MachineBasicBlock::iterator MBBI = MBB.getLastNonDebugInstr();
687 MachineFrameInfo &MFI = MF.getFrameInfo();
688 MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
690 const MipsSEInstrInfo &TII =
691 *static_cast<const MipsSEInstrInfo *>(STI.getInstrInfo());
692 const MipsRegisterInfo &RegInfo =
693 *static_cast<const MipsRegisterInfo *>(STI.getRegisterInfo());
695 DebugLoc DL = MBBI->getDebugLoc();
696 MipsABIInfo ABI = STI.getABI();
697 unsigned SP = ABI.GetStackPtr();
698 unsigned FP = ABI.GetFramePtr();
699 unsigned ZERO = ABI.GetNullPtr();
700 unsigned MOVE = ABI.GetGPRMoveOp();
702 // if framepointer enabled, restore the stack pointer.
704 // Find the first instruction that restores a callee-saved register.
705 MachineBasicBlock::iterator I = MBBI;
707 for (unsigned i = 0; i < MFI.getCalleeSavedInfo().size(); ++i)
710 // Insert instruction "move $sp, $fp" at this location.
711 BuildMI(MBB, I, DL, TII.get(MOVE), SP).addReg(FP).addReg(ZERO);
714 if (MipsFI->callsEhReturn()) {
715 const TargetRegisterClass *RC =
716 ABI.ArePtrs64bit() ? &Mips::GPR64RegClass : &Mips::GPR32RegClass;
718 // Find first instruction that restores a callee-saved register.
719 MachineBasicBlock::iterator I = MBBI;
720 for (unsigned i = 0; i < MFI.getCalleeSavedInfo().size(); ++i)
723 // Insert instructions that restore eh data registers.
724 for (int J = 0; J < 4; ++J) {
725 TII.loadRegFromStackSlot(MBB, I, ABI.GetEhDataReg(J),
726 MipsFI->getEhDataRegFI(J), RC, &RegInfo);
730 if (MF.getFunction()->hasFnAttribute("interrupt"))
731 emitInterruptEpilogueStub(MF, MBB);
733 // Get the number of bytes from FrameInfo
734 uint64_t StackSize = MFI.getStackSize();
740 TII.adjustStackPtr(SP, StackSize, MBB, MBBI);
743 void MipsSEFrameLowering::emitInterruptEpilogueStub(
744 MachineFunction &MF, MachineBasicBlock &MBB) const {
745 MachineBasicBlock::iterator MBBI = MBB.getLastNonDebugInstr();
746 MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
747 DebugLoc DL = MBBI != MBB.end() ? MBBI->getDebugLoc() : DebugLoc();
749 // Perform ISR handling like GCC
750 const TargetRegisterClass *PtrRC = &Mips::GPR32RegClass;
752 // Disable Interrupts.
753 BuildMI(MBB, MBBI, DL, STI.getInstrInfo()->get(Mips::DI), Mips::ZERO);
754 BuildMI(MBB, MBBI, DL, STI.getInstrInfo()->get(Mips::EHB));
757 STI.getInstrInfo()->loadRegFromStackSlot(MBB, MBBI, Mips::K1,
758 MipsFI->getISRRegFI(0), PtrRC,
759 STI.getRegisterInfo());
760 BuildMI(MBB, MBBI, DL, STI.getInstrInfo()->get(Mips::MTC0), Mips::COP014)
765 STI.getInstrInfo()->loadRegFromStackSlot(MBB, MBBI, Mips::K1,
766 MipsFI->getISRRegFI(1), PtrRC,
767 STI.getRegisterInfo());
768 BuildMI(MBB, MBBI, DL, STI.getInstrInfo()->get(Mips::MTC0), Mips::COP012)
773 int MipsSEFrameLowering::getFrameIndexReference(const MachineFunction &MF,
775 unsigned &FrameReg) const {
776 const MachineFrameInfo &MFI = MF.getFrameInfo();
777 MipsABIInfo ABI = STI.getABI();
779 if (MFI.isFixedObjectIndex(FI))
780 FrameReg = hasFP(MF) ? ABI.GetFramePtr() : ABI.GetStackPtr();
782 FrameReg = hasBP(MF) ? ABI.GetBasePtr() : ABI.GetStackPtr();
784 return MFI.getObjectOffset(FI) + MFI.getStackSize() -
785 getOffsetOfLocalArea() + MFI.getOffsetAdjustment();
788 bool MipsSEFrameLowering::
789 spillCalleeSavedRegisters(MachineBasicBlock &MBB,
790 MachineBasicBlock::iterator MI,
791 const std::vector<CalleeSavedInfo> &CSI,
792 const TargetRegisterInfo *TRI) const {
793 MachineFunction *MF = MBB.getParent();
794 MachineBasicBlock *EntryBlock = &MF->front();
795 const TargetInstrInfo &TII = *STI.getInstrInfo();
797 for (unsigned i = 0, e = CSI.size(); i != e; ++i) {
798 // Add the callee-saved register as live-in. Do not add if the register is
799 // RA and return address is taken, because it has already been added in
800 // method MipsTargetLowering::lowerRETURNADDR.
801 // It's killed at the spill, unless the register is RA and return address
803 unsigned Reg = CSI[i].getReg();
804 bool IsRAAndRetAddrIsTaken = (Reg == Mips::RA || Reg == Mips::RA_64)
805 && MF->getFrameInfo().isReturnAddressTaken();
806 if (!IsRAAndRetAddrIsTaken)
807 EntryBlock->addLiveIn(Reg);
809 // ISRs require HI/LO to be spilled into kernel registers to be then
810 // spilled to the stack frame.
811 bool IsLOHI = (Reg == Mips::LO0 || Reg == Mips::LO0_64 ||
812 Reg == Mips::HI0 || Reg == Mips::HI0_64);
813 const Function *Func = MBB.getParent()->getFunction();
814 if (IsLOHI && Func->hasFnAttribute("interrupt")) {
815 DebugLoc DL = MI->getDebugLoc();
818 if (!STI.getABI().ArePtrs64bit()) {
819 Op = (Reg == Mips::HI0) ? Mips::MFHI : Mips::MFLO;
822 Op = (Reg == Mips::HI0) ? Mips::MFHI64 : Mips::MFLO64;
825 BuildMI(MBB, MI, DL, TII.get(Op), Mips::K0)
826 .setMIFlag(MachineInstr::FrameSetup);
829 // Insert the spill to the stack frame.
830 bool IsKill = !IsRAAndRetAddrIsTaken;
831 const TargetRegisterClass *RC = TRI->getMinimalPhysRegClass(Reg);
832 TII.storeRegToStackSlot(*EntryBlock, MI, Reg, IsKill,
833 CSI[i].getFrameIdx(), RC, TRI);
840 MipsSEFrameLowering::hasReservedCallFrame(const MachineFunction &MF) const {
841 const MachineFrameInfo &MFI = MF.getFrameInfo();
842 // Reserve call frame if the size of the maximum call frame fits into 16-bit
843 // immediate field and there are no variable sized objects on the stack.
844 // Make sure the second register scavenger spill slot can be accessed with one
846 return isInt<16>(MFI.getMaxCallFrameSize() + getStackAlignment()) &&
847 !MFI.hasVarSizedObjects();
850 /// Mark \p Reg and all registers aliasing it in the bitset.
851 static void setAliasRegs(MachineFunction &MF, BitVector &SavedRegs,
853 const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
854 for (MCRegAliasIterator AI(Reg, TRI, true); AI.isValid(); ++AI)
858 void MipsSEFrameLowering::determineCalleeSaves(MachineFunction &MF,
859 BitVector &SavedRegs,
860 RegScavenger *RS) const {
861 TargetFrameLowering::determineCalleeSaves(MF, SavedRegs, RS);
862 const TargetRegisterInfo *TRI = MF.getSubtarget().getRegisterInfo();
863 MipsFunctionInfo *MipsFI = MF.getInfo<MipsFunctionInfo>();
864 MipsABIInfo ABI = STI.getABI();
865 unsigned FP = ABI.GetFramePtr();
866 unsigned BP = ABI.IsN64() ? Mips::S7_64 : Mips::S7;
868 // Mark $fp as used if function has dedicated frame pointer.
870 setAliasRegs(MF, SavedRegs, FP);
871 // Mark $s7 as used if function has dedicated base pointer.
873 setAliasRegs(MF, SavedRegs, BP);
875 // Create spill slots for eh data registers if function calls eh_return.
876 if (MipsFI->callsEhReturn())
877 MipsFI->createEhDataRegsFI();
879 // Create spill slots for Coprocessor 0 registers if function is an ISR.
881 MipsFI->createISRRegFI();
883 // Expand pseudo instructions which load, store or copy accumulators.
884 // Add an emergency spill slot if a pseudo was expanded.
885 if (ExpandPseudo(MF).expand()) {
886 // The spill slot should be half the size of the accumulator. If target is
887 // mips64, it should be 64-bit, otherwise it should be 32-bt.
888 const TargetRegisterClass &RC = STI.hasMips64() ?
889 Mips::GPR64RegClass : Mips::GPR32RegClass;
890 int FI = MF.getFrameInfo().CreateStackObject(TRI->getSpillSize(RC),
891 TRI->getSpillAlignment(RC),
893 RS->addScavengingFrameIndex(FI);
896 // Set scavenging frame index if necessary.
897 uint64_t MaxSPOffset = MF.getInfo<MipsFunctionInfo>()->getIncomingArgSize() +
898 estimateStackSize(MF);
900 if (isInt<16>(MaxSPOffset))
903 const TargetRegisterClass &RC =
904 ABI.ArePtrs64bit() ? Mips::GPR64RegClass : Mips::GPR32RegClass;
905 int FI = MF.getFrameInfo().CreateStackObject(TRI->getSpillSize(RC),
906 TRI->getSpillAlignment(RC),
908 RS->addScavengingFrameIndex(FI);
911 const MipsFrameLowering *
912 llvm::createMipsSEFrameLowering(const MipsSubtarget &ST) {
913 return new MipsSEFrameLowering(ST);