1 //===- AMDGPUInstructionSelector.cpp ----------------------------*- C++ -*-==//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 /// \file
9 /// This file implements the targeting of the InstructionSelector class for
10 /// AMDGPU.
11 /// \todo This should be generated by TableGen.
12 //===----------------------------------------------------------------------===//
13 
14 #include "AMDGPUInstructionSelector.h"
15 #include "AMDGPU.h"
16 #include "AMDGPUGlobalISelUtils.h"
17 #include "AMDGPUInstrInfo.h"
18 #include "AMDGPURegisterBankInfo.h"
19 #include "AMDGPUTargetMachine.h"
20 #include "SIMachineFunctionInfo.h"
21 #include "Utils/AMDGPUBaseInfo.h"
22 #include "llvm/CodeGen/GlobalISel/GISelKnownBits.h"
23 #include "llvm/CodeGen/GlobalISel/InstructionSelectorImpl.h"
24 #include "llvm/CodeGen/GlobalISel/MIPatternMatch.h"
25 #include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
26 #include "llvm/IR/DiagnosticInfo.h"
27 #include "llvm/IR/IntrinsicsAMDGPU.h"
28 
29 #define DEBUG_TYPE "amdgpu-isel"
30 
31 using namespace llvm;
32 using namespace MIPatternMatch;
33 
34 static cl::opt<bool> AllowRiskySelect(
35   "amdgpu-global-isel-risky-select",
36   cl::desc("Allow GlobalISel to select cases that are likely to not work yet"),
37   cl::init(false),
38   cl::ReallyHidden);
39 
40 #define GET_GLOBALISEL_IMPL
41 #define AMDGPUSubtarget GCNSubtarget
42 #include "AMDGPUGenGlobalISel.inc"
43 #undef GET_GLOBALISEL_IMPL
44 #undef AMDGPUSubtarget
45 
46 AMDGPUInstructionSelector::AMDGPUInstructionSelector(
47     const GCNSubtarget &STI, const AMDGPURegisterBankInfo &RBI,
48     const AMDGPUTargetMachine &TM)
49     : TII(*STI.getInstrInfo()), TRI(*STI.getRegisterInfo()), RBI(RBI), TM(TM),
50       STI(STI),
51       EnableLateStructurizeCFG(AMDGPUTargetMachine::EnableLateStructurizeCFG),
52 #define GET_GLOBALISEL_PREDICATES_INIT
53 #include "AMDGPUGenGlobalISel.inc"
54 #undef GET_GLOBALISEL_PREDICATES_INIT
55 #define GET_GLOBALISEL_TEMPORARIES_INIT
56 #include "AMDGPUGenGlobalISel.inc"
57 #undef GET_GLOBALISEL_TEMPORARIES_INIT
58 {
59 }
60 
61 const char *AMDGPUInstructionSelector::getName() { return DEBUG_TYPE; }
62 
63 void AMDGPUInstructionSelector::setupMF(MachineFunction &MF, GISelKnownBits *KB,
64                                         CodeGenCoverage &CoverageInfo,
65                                         ProfileSummaryInfo *PSI,
66                                         BlockFrequencyInfo *BFI) {
67   MRI = &MF.getRegInfo();
68   Subtarget = &MF.getSubtarget<GCNSubtarget>();
69   InstructionSelector::setupMF(MF, KB, CoverageInfo, PSI, BFI);
70 }
71 
72 bool AMDGPUInstructionSelector::isVCC(Register Reg,
73                                       const MachineRegisterInfo &MRI) const {
74   // The verifier is oblivious to s1 being a valid value for wavesize registers.
75   if (Reg.isPhysical())
76     return false;
77 
78   auto &RegClassOrBank = MRI.getRegClassOrRegBank(Reg);
79   const TargetRegisterClass *RC =
80       RegClassOrBank.dyn_cast<const TargetRegisterClass*>();
81   if (RC) {
82     const LLT Ty = MRI.getType(Reg);
83     return RC->hasSuperClassEq(TRI.getBoolRC()) &&
84            Ty.isValid() && Ty.getSizeInBits() == 1;
85   }
86 
87   const RegisterBank *RB = RegClassOrBank.get<const RegisterBank *>();
88   return RB->getID() == AMDGPU::VCCRegBankID;
89 }
90 
91 bool AMDGPUInstructionSelector::constrainCopyLikeIntrin(MachineInstr &MI,
92                                                         unsigned NewOpc) const {
93   MI.setDesc(TII.get(NewOpc));
94   MI.RemoveOperand(1); // Remove intrinsic ID.
95   MI.addOperand(*MF, MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
96 
97   MachineOperand &Dst = MI.getOperand(0);
98   MachineOperand &Src = MI.getOperand(1);
99 
100   // TODO: This should be legalized to s32 if needed
101   if (MRI->getType(Dst.getReg()) == LLT::scalar(1))
102     return false;
103 
104   const TargetRegisterClass *DstRC
105     = TRI.getConstrainedRegClassForOperand(Dst, *MRI);
106   const TargetRegisterClass *SrcRC
107     = TRI.getConstrainedRegClassForOperand(Src, *MRI);
108   if (!DstRC || DstRC != SrcRC)
109     return false;
110 
111   return RBI.constrainGenericRegister(Dst.getReg(), *DstRC, *MRI) &&
112          RBI.constrainGenericRegister(Src.getReg(), *SrcRC, *MRI);
113 }
114 
115 bool AMDGPUInstructionSelector::selectCOPY(MachineInstr &I) const {
116   const DebugLoc &DL = I.getDebugLoc();
117   MachineBasicBlock *BB = I.getParent();
118   I.setDesc(TII.get(TargetOpcode::COPY));
119 
120   const MachineOperand &Src = I.getOperand(1);
121   MachineOperand &Dst = I.getOperand(0);
122   Register DstReg = Dst.getReg();
123   Register SrcReg = Src.getReg();
124 
125   if (isVCC(DstReg, *MRI)) {
126     if (SrcReg == AMDGPU::SCC) {
127       const TargetRegisterClass *RC
128         = TRI.getConstrainedRegClassForOperand(Dst, *MRI);
129       if (!RC)
130         return true;
131       return RBI.constrainGenericRegister(DstReg, *RC, *MRI);
132     }
133 
134     if (!isVCC(SrcReg, *MRI)) {
135       // TODO: Should probably leave the copy and let copyPhysReg expand it.
136       if (!RBI.constrainGenericRegister(DstReg, *TRI.getBoolRC(), *MRI))
137         return false;
138 
139       const TargetRegisterClass *SrcRC
140         = TRI.getConstrainedRegClassForOperand(Src, *MRI);
141 
142       Optional<ValueAndVReg> ConstVal =
143           getIConstantVRegValWithLookThrough(SrcReg, *MRI, true);
144       if (ConstVal) {
145         unsigned MovOpc =
146             STI.isWave64() ? AMDGPU::S_MOV_B64 : AMDGPU::S_MOV_B32;
147         BuildMI(*BB, &I, DL, TII.get(MovOpc), DstReg)
148             .addImm(ConstVal->Value.getBoolValue() ? -1 : 0);
149       } else {
150         Register MaskedReg = MRI->createVirtualRegister(SrcRC);
151 
152         // We can't trust the high bits at this point, so clear them.
153 
154         // TODO: Skip masking high bits if def is known boolean.
155 
156         unsigned AndOpc =
157             TRI.isSGPRClass(SrcRC) ? AMDGPU::S_AND_B32 : AMDGPU::V_AND_B32_e32;
158         BuildMI(*BB, &I, DL, TII.get(AndOpc), MaskedReg)
159             .addImm(1)
160             .addReg(SrcReg);
161         BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_CMP_NE_U32_e64), DstReg)
162             .addImm(0)
163             .addReg(MaskedReg);
164       }
165 
166       if (!MRI->getRegClassOrNull(SrcReg))
167         MRI->setRegClass(SrcReg, SrcRC);
168       I.eraseFromParent();
169       return true;
170     }
171 
172     const TargetRegisterClass *RC =
173       TRI.getConstrainedRegClassForOperand(Dst, *MRI);
174     if (RC && !RBI.constrainGenericRegister(DstReg, *RC, *MRI))
175       return false;
176 
177     return true;
178   }
179 
180   for (const MachineOperand &MO : I.operands()) {
181     if (MO.getReg().isPhysical())
182       continue;
183 
184     const TargetRegisterClass *RC =
185             TRI.getConstrainedRegClassForOperand(MO, *MRI);
186     if (!RC)
187       continue;
188     RBI.constrainGenericRegister(MO.getReg(), *RC, *MRI);
189   }
190   return true;
191 }
192 
193 bool AMDGPUInstructionSelector::selectPHI(MachineInstr &I) const {
194   const Register DefReg = I.getOperand(0).getReg();
195   const LLT DefTy = MRI->getType(DefReg);
196   if (DefTy == LLT::scalar(1)) {
197     if (!AllowRiskySelect) {
198       LLVM_DEBUG(dbgs() << "Skipping risky boolean phi\n");
199       return false;
200     }
201 
202     LLVM_DEBUG(dbgs() << "Selecting risky boolean phi\n");
203   }
204 
205   // TODO: Verify this doesn't have insane operands (i.e. VGPR to SGPR copy)
206 
207   const RegClassOrRegBank &RegClassOrBank =
208     MRI->getRegClassOrRegBank(DefReg);
209 
210   const TargetRegisterClass *DefRC
211     = RegClassOrBank.dyn_cast<const TargetRegisterClass *>();
212   if (!DefRC) {
213     if (!DefTy.isValid()) {
214       LLVM_DEBUG(dbgs() << "PHI operand has no type, not a gvreg?\n");
215       return false;
216     }
217 
218     const RegisterBank &RB = *RegClassOrBank.get<const RegisterBank *>();
219     DefRC = TRI.getRegClassForTypeOnBank(DefTy, RB, *MRI);
220     if (!DefRC) {
221       LLVM_DEBUG(dbgs() << "PHI operand has unexpected size/bank\n");
222       return false;
223     }
224   }
225 
226   // TODO: Verify that all registers have the same bank
227   I.setDesc(TII.get(TargetOpcode::PHI));
228   return RBI.constrainGenericRegister(DefReg, *DefRC, *MRI);
229 }
230 
231 MachineOperand
232 AMDGPUInstructionSelector::getSubOperand64(MachineOperand &MO,
233                                            const TargetRegisterClass &SubRC,
234                                            unsigned SubIdx) const {
235 
236   MachineInstr *MI = MO.getParent();
237   MachineBasicBlock *BB = MO.getParent()->getParent();
238   Register DstReg = MRI->createVirtualRegister(&SubRC);
239 
240   if (MO.isReg()) {
241     unsigned ComposedSubIdx = TRI.composeSubRegIndices(MO.getSubReg(), SubIdx);
242     Register Reg = MO.getReg();
243     BuildMI(*BB, MI, MI->getDebugLoc(), TII.get(AMDGPU::COPY), DstReg)
244             .addReg(Reg, 0, ComposedSubIdx);
245 
246     return MachineOperand::CreateReg(DstReg, MO.isDef(), MO.isImplicit(),
247                                      MO.isKill(), MO.isDead(), MO.isUndef(),
248                                      MO.isEarlyClobber(), 0, MO.isDebug(),
249                                      MO.isInternalRead());
250   }
251 
252   assert(MO.isImm());
253 
254   APInt Imm(64, MO.getImm());
255 
256   switch (SubIdx) {
257   default:
258     llvm_unreachable("do not know to split immediate with this sub index.");
259   case AMDGPU::sub0:
260     return MachineOperand::CreateImm(Imm.getLoBits(32).getSExtValue());
261   case AMDGPU::sub1:
262     return MachineOperand::CreateImm(Imm.getHiBits(32).getSExtValue());
263   }
264 }
265 
266 static unsigned getLogicalBitOpcode(unsigned Opc, bool Is64) {
267   switch (Opc) {
268   case AMDGPU::G_AND:
269     return Is64 ? AMDGPU::S_AND_B64 : AMDGPU::S_AND_B32;
270   case AMDGPU::G_OR:
271     return Is64 ? AMDGPU::S_OR_B64 : AMDGPU::S_OR_B32;
272   case AMDGPU::G_XOR:
273     return Is64 ? AMDGPU::S_XOR_B64 : AMDGPU::S_XOR_B32;
274   default:
275     llvm_unreachable("not a bit op");
276   }
277 }
278 
279 bool AMDGPUInstructionSelector::selectG_AND_OR_XOR(MachineInstr &I) const {
280   Register DstReg = I.getOperand(0).getReg();
281   unsigned Size = RBI.getSizeInBits(DstReg, *MRI, TRI);
282 
283   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
284   if (DstRB->getID() != AMDGPU::SGPRRegBankID &&
285       DstRB->getID() != AMDGPU::VCCRegBankID)
286     return false;
287 
288   bool Is64 = Size > 32 || (DstRB->getID() == AMDGPU::VCCRegBankID &&
289                             STI.isWave64());
290   I.setDesc(TII.get(getLogicalBitOpcode(I.getOpcode(), Is64)));
291 
292   // Dead implicit-def of scc
293   I.addOperand(MachineOperand::CreateReg(AMDGPU::SCC, true, // isDef
294                                          true, // isImp
295                                          false, // isKill
296                                          true)); // isDead
297   return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
298 }
299 
300 bool AMDGPUInstructionSelector::selectG_ADD_SUB(MachineInstr &I) const {
301   MachineBasicBlock *BB = I.getParent();
302   MachineFunction *MF = BB->getParent();
303   Register DstReg = I.getOperand(0).getReg();
304   const DebugLoc &DL = I.getDebugLoc();
305   LLT Ty = MRI->getType(DstReg);
306   if (Ty.isVector())
307     return false;
308 
309   unsigned Size = Ty.getSizeInBits();
310   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
311   const bool IsSALU = DstRB->getID() == AMDGPU::SGPRRegBankID;
312   const bool Sub = I.getOpcode() == TargetOpcode::G_SUB;
313 
314   if (Size == 32) {
315     if (IsSALU) {
316       const unsigned Opc = Sub ? AMDGPU::S_SUB_U32 : AMDGPU::S_ADD_U32;
317       MachineInstr *Add =
318         BuildMI(*BB, &I, DL, TII.get(Opc), DstReg)
319         .add(I.getOperand(1))
320         .add(I.getOperand(2));
321       I.eraseFromParent();
322       return constrainSelectedInstRegOperands(*Add, TII, TRI, RBI);
323     }
324 
325     if (STI.hasAddNoCarry()) {
326       const unsigned Opc = Sub ? AMDGPU::V_SUB_U32_e64 : AMDGPU::V_ADD_U32_e64;
327       I.setDesc(TII.get(Opc));
328       I.addOperand(*MF, MachineOperand::CreateImm(0));
329       I.addOperand(*MF, MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
330       return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
331     }
332 
333     const unsigned Opc = Sub ? AMDGPU::V_SUB_CO_U32_e64 : AMDGPU::V_ADD_CO_U32_e64;
334 
335     Register UnusedCarry = MRI->createVirtualRegister(TRI.getWaveMaskRegClass());
336     MachineInstr *Add
337       = BuildMI(*BB, &I, DL, TII.get(Opc), DstReg)
338       .addDef(UnusedCarry, RegState::Dead)
339       .add(I.getOperand(1))
340       .add(I.getOperand(2))
341       .addImm(0);
342     I.eraseFromParent();
343     return constrainSelectedInstRegOperands(*Add, TII, TRI, RBI);
344   }
345 
346   assert(!Sub && "illegal sub should not reach here");
347 
348   const TargetRegisterClass &RC
349     = IsSALU ? AMDGPU::SReg_64_XEXECRegClass : AMDGPU::VReg_64RegClass;
350   const TargetRegisterClass &HalfRC
351     = IsSALU ? AMDGPU::SReg_32RegClass : AMDGPU::VGPR_32RegClass;
352 
353   MachineOperand Lo1(getSubOperand64(I.getOperand(1), HalfRC, AMDGPU::sub0));
354   MachineOperand Lo2(getSubOperand64(I.getOperand(2), HalfRC, AMDGPU::sub0));
355   MachineOperand Hi1(getSubOperand64(I.getOperand(1), HalfRC, AMDGPU::sub1));
356   MachineOperand Hi2(getSubOperand64(I.getOperand(2), HalfRC, AMDGPU::sub1));
357 
358   Register DstLo = MRI->createVirtualRegister(&HalfRC);
359   Register DstHi = MRI->createVirtualRegister(&HalfRC);
360 
361   if (IsSALU) {
362     BuildMI(*BB, &I, DL, TII.get(AMDGPU::S_ADD_U32), DstLo)
363       .add(Lo1)
364       .add(Lo2);
365     BuildMI(*BB, &I, DL, TII.get(AMDGPU::S_ADDC_U32), DstHi)
366       .add(Hi1)
367       .add(Hi2);
368   } else {
369     const TargetRegisterClass *CarryRC = TRI.getWaveMaskRegClass();
370     Register CarryReg = MRI->createVirtualRegister(CarryRC);
371     BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_ADD_CO_U32_e64), DstLo)
372       .addDef(CarryReg)
373       .add(Lo1)
374       .add(Lo2)
375       .addImm(0);
376     MachineInstr *Addc = BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_ADDC_U32_e64), DstHi)
377       .addDef(MRI->createVirtualRegister(CarryRC), RegState::Dead)
378       .add(Hi1)
379       .add(Hi2)
380       .addReg(CarryReg, RegState::Kill)
381       .addImm(0);
382 
383     if (!constrainSelectedInstRegOperands(*Addc, TII, TRI, RBI))
384       return false;
385   }
386 
387   BuildMI(*BB, &I, DL, TII.get(AMDGPU::REG_SEQUENCE), DstReg)
388     .addReg(DstLo)
389     .addImm(AMDGPU::sub0)
390     .addReg(DstHi)
391     .addImm(AMDGPU::sub1);
392 
393 
394   if (!RBI.constrainGenericRegister(DstReg, RC, *MRI))
395     return false;
396 
397   I.eraseFromParent();
398   return true;
399 }
400 
401 bool AMDGPUInstructionSelector::selectG_UADDO_USUBO_UADDE_USUBE(
402   MachineInstr &I) const {
403   MachineBasicBlock *BB = I.getParent();
404   MachineFunction *MF = BB->getParent();
405   const DebugLoc &DL = I.getDebugLoc();
406   Register Dst0Reg = I.getOperand(0).getReg();
407   Register Dst1Reg = I.getOperand(1).getReg();
408   const bool IsAdd = I.getOpcode() == AMDGPU::G_UADDO ||
409                      I.getOpcode() == AMDGPU::G_UADDE;
410   const bool HasCarryIn = I.getOpcode() == AMDGPU::G_UADDE ||
411                           I.getOpcode() == AMDGPU::G_USUBE;
412 
413   if (isVCC(Dst1Reg, *MRI)) {
414     unsigned NoCarryOpc =
415         IsAdd ? AMDGPU::V_ADD_CO_U32_e64 : AMDGPU::V_SUB_CO_U32_e64;
416     unsigned CarryOpc = IsAdd ? AMDGPU::V_ADDC_U32_e64 : AMDGPU::V_SUBB_U32_e64;
417     I.setDesc(TII.get(HasCarryIn ? CarryOpc : NoCarryOpc));
418     I.addOperand(*MF, MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
419     I.addOperand(*MF, MachineOperand::CreateImm(0));
420     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
421   }
422 
423   Register Src0Reg = I.getOperand(2).getReg();
424   Register Src1Reg = I.getOperand(3).getReg();
425 
426   if (HasCarryIn) {
427     BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), AMDGPU::SCC)
428       .addReg(I.getOperand(4).getReg());
429   }
430 
431   unsigned NoCarryOpc = IsAdd ? AMDGPU::S_ADD_U32 : AMDGPU::S_SUB_U32;
432   unsigned CarryOpc = IsAdd ? AMDGPU::S_ADDC_U32 : AMDGPU::S_SUBB_U32;
433 
434   BuildMI(*BB, &I, DL, TII.get(HasCarryIn ? CarryOpc : NoCarryOpc), Dst0Reg)
435     .add(I.getOperand(2))
436     .add(I.getOperand(3));
437   BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), Dst1Reg)
438     .addReg(AMDGPU::SCC);
439 
440   if (!MRI->getRegClassOrNull(Dst1Reg))
441     MRI->setRegClass(Dst1Reg, &AMDGPU::SReg_32RegClass);
442 
443   if (!RBI.constrainGenericRegister(Dst0Reg, AMDGPU::SReg_32RegClass, *MRI) ||
444       !RBI.constrainGenericRegister(Src0Reg, AMDGPU::SReg_32RegClass, *MRI) ||
445       !RBI.constrainGenericRegister(Src1Reg, AMDGPU::SReg_32RegClass, *MRI))
446     return false;
447 
448   if (HasCarryIn &&
449       !RBI.constrainGenericRegister(I.getOperand(4).getReg(),
450                                     AMDGPU::SReg_32RegClass, *MRI))
451     return false;
452 
453   I.eraseFromParent();
454   return true;
455 }
456 
457 // TODO: We should probably legalize these to only using 32-bit results.
458 bool AMDGPUInstructionSelector::selectG_EXTRACT(MachineInstr &I) const {
459   MachineBasicBlock *BB = I.getParent();
460   Register DstReg = I.getOperand(0).getReg();
461   Register SrcReg = I.getOperand(1).getReg();
462   LLT DstTy = MRI->getType(DstReg);
463   LLT SrcTy = MRI->getType(SrcReg);
464   const unsigned SrcSize = SrcTy.getSizeInBits();
465   unsigned DstSize = DstTy.getSizeInBits();
466 
467   // TODO: Should handle any multiple of 32 offset.
468   unsigned Offset = I.getOperand(2).getImm();
469   if (Offset % 32 != 0 || DstSize > 128)
470     return false;
471 
472   // 16-bit operations really use 32-bit registers.
473   // FIXME: Probably should not allow 16-bit G_EXTRACT results.
474   if (DstSize == 16)
475     DstSize = 32;
476 
477   const TargetRegisterClass *DstRC =
478     TRI.getConstrainedRegClassForOperand(I.getOperand(0), *MRI);
479   if (!DstRC || !RBI.constrainGenericRegister(DstReg, *DstRC, *MRI))
480     return false;
481 
482   const RegisterBank *SrcBank = RBI.getRegBank(SrcReg, *MRI, TRI);
483   const TargetRegisterClass *SrcRC =
484     TRI.getRegClassForSizeOnBank(SrcSize, *SrcBank, *MRI);
485   if (!SrcRC)
486     return false;
487   unsigned SubReg = SIRegisterInfo::getSubRegFromChannel(Offset / 32,
488                                                          DstSize / 32);
489   SrcRC = TRI.getSubClassWithSubReg(SrcRC, SubReg);
490   if (!SrcRC)
491     return false;
492 
493   SrcReg = constrainOperandRegClass(*MF, TRI, *MRI, TII, RBI, I,
494                                     *SrcRC, I.getOperand(1));
495   const DebugLoc &DL = I.getDebugLoc();
496   BuildMI(*BB, &I, DL, TII.get(TargetOpcode::COPY), DstReg)
497     .addReg(SrcReg, 0, SubReg);
498 
499   I.eraseFromParent();
500   return true;
501 }
502 
503 bool AMDGPUInstructionSelector::selectG_MERGE_VALUES(MachineInstr &MI) const {
504   MachineBasicBlock *BB = MI.getParent();
505   Register DstReg = MI.getOperand(0).getReg();
506   LLT DstTy = MRI->getType(DstReg);
507   LLT SrcTy = MRI->getType(MI.getOperand(1).getReg());
508 
509   const unsigned SrcSize = SrcTy.getSizeInBits();
510   if (SrcSize < 32)
511     return selectImpl(MI, *CoverageInfo);
512 
513   const DebugLoc &DL = MI.getDebugLoc();
514   const RegisterBank *DstBank = RBI.getRegBank(DstReg, *MRI, TRI);
515   const unsigned DstSize = DstTy.getSizeInBits();
516   const TargetRegisterClass *DstRC =
517     TRI.getRegClassForSizeOnBank(DstSize, *DstBank, *MRI);
518   if (!DstRC)
519     return false;
520 
521   ArrayRef<int16_t> SubRegs = TRI.getRegSplitParts(DstRC, SrcSize / 8);
522   MachineInstrBuilder MIB =
523     BuildMI(*BB, &MI, DL, TII.get(TargetOpcode::REG_SEQUENCE), DstReg);
524   for (int I = 0, E = MI.getNumOperands() - 1; I != E; ++I) {
525     MachineOperand &Src = MI.getOperand(I + 1);
526     MIB.addReg(Src.getReg(), getUndefRegState(Src.isUndef()));
527     MIB.addImm(SubRegs[I]);
528 
529     const TargetRegisterClass *SrcRC
530       = TRI.getConstrainedRegClassForOperand(Src, *MRI);
531     if (SrcRC && !RBI.constrainGenericRegister(Src.getReg(), *SrcRC, *MRI))
532       return false;
533   }
534 
535   if (!RBI.constrainGenericRegister(DstReg, *DstRC, *MRI))
536     return false;
537 
538   MI.eraseFromParent();
539   return true;
540 }
541 
542 bool AMDGPUInstructionSelector::selectG_UNMERGE_VALUES(MachineInstr &MI) const {
543   MachineBasicBlock *BB = MI.getParent();
544   const int NumDst = MI.getNumOperands() - 1;
545 
546   MachineOperand &Src = MI.getOperand(NumDst);
547 
548   Register SrcReg = Src.getReg();
549   Register DstReg0 = MI.getOperand(0).getReg();
550   LLT DstTy = MRI->getType(DstReg0);
551   LLT SrcTy = MRI->getType(SrcReg);
552 
553   const unsigned DstSize = DstTy.getSizeInBits();
554   const unsigned SrcSize = SrcTy.getSizeInBits();
555   const DebugLoc &DL = MI.getDebugLoc();
556   const RegisterBank *SrcBank = RBI.getRegBank(SrcReg, *MRI, TRI);
557 
558   const TargetRegisterClass *SrcRC =
559     TRI.getRegClassForSizeOnBank(SrcSize, *SrcBank, *MRI);
560   if (!SrcRC || !RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI))
561     return false;
562 
563   // Note we could have mixed SGPR and VGPR destination banks for an SGPR
564   // source, and this relies on the fact that the same subregister indices are
565   // used for both.
566   ArrayRef<int16_t> SubRegs = TRI.getRegSplitParts(SrcRC, DstSize / 8);
567   for (int I = 0, E = NumDst; I != E; ++I) {
568     MachineOperand &Dst = MI.getOperand(I);
569     BuildMI(*BB, &MI, DL, TII.get(TargetOpcode::COPY), Dst.getReg())
570       .addReg(SrcReg, 0, SubRegs[I]);
571 
572     // Make sure the subregister index is valid for the source register.
573     SrcRC = TRI.getSubClassWithSubReg(SrcRC, SubRegs[I]);
574     if (!SrcRC || !RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI))
575       return false;
576 
577     const TargetRegisterClass *DstRC =
578       TRI.getConstrainedRegClassForOperand(Dst, *MRI);
579     if (DstRC && !RBI.constrainGenericRegister(Dst.getReg(), *DstRC, *MRI))
580       return false;
581   }
582 
583   MI.eraseFromParent();
584   return true;
585 }
586 
587 bool AMDGPUInstructionSelector::selectG_BUILD_VECTOR_TRUNC(
588   MachineInstr &MI) const {
589   if (selectImpl(MI, *CoverageInfo))
590     return true;
591 
592   const LLT S32 = LLT::scalar(32);
593   const LLT V2S16 = LLT::fixed_vector(2, 16);
594 
595   Register Dst = MI.getOperand(0).getReg();
596   if (MRI->getType(Dst) != V2S16)
597     return false;
598 
599   const RegisterBank *DstBank = RBI.getRegBank(Dst, *MRI, TRI);
600   if (DstBank->getID() != AMDGPU::SGPRRegBankID)
601     return false;
602 
603   Register Src0 = MI.getOperand(1).getReg();
604   Register Src1 = MI.getOperand(2).getReg();
605   if (MRI->getType(Src0) != S32)
606     return false;
607 
608   const DebugLoc &DL = MI.getDebugLoc();
609   MachineBasicBlock *BB = MI.getParent();
610 
611   auto ConstSrc1 = getAnyConstantVRegValWithLookThrough(Src1, *MRI, true, true);
612   if (ConstSrc1) {
613     auto ConstSrc0 =
614         getAnyConstantVRegValWithLookThrough(Src0, *MRI, true, true);
615     if (ConstSrc0) {
616       const int64_t K0 = ConstSrc0->Value.getSExtValue();
617       const int64_t K1 = ConstSrc1->Value.getSExtValue();
618       uint32_t Lo16 = static_cast<uint32_t>(K0) & 0xffff;
619       uint32_t Hi16 = static_cast<uint32_t>(K1) & 0xffff;
620 
621       BuildMI(*BB, &MI, DL, TII.get(AMDGPU::S_MOV_B32), Dst)
622         .addImm(Lo16 | (Hi16 << 16));
623       MI.eraseFromParent();
624       return RBI.constrainGenericRegister(Dst, AMDGPU::SReg_32RegClass, *MRI);
625     }
626   }
627 
628   // TODO: This should probably be a combine somewhere
629   // (build_vector_trunc $src0, undef -> copy $src0
630   MachineInstr *Src1Def = getDefIgnoringCopies(Src1, *MRI);
631   if (Src1Def && Src1Def->getOpcode() == AMDGPU::G_IMPLICIT_DEF) {
632     MI.setDesc(TII.get(AMDGPU::COPY));
633     MI.RemoveOperand(2);
634     return RBI.constrainGenericRegister(Dst, AMDGPU::SReg_32RegClass, *MRI) &&
635            RBI.constrainGenericRegister(Src0, AMDGPU::SReg_32RegClass, *MRI);
636   }
637 
638   Register ShiftSrc0;
639   Register ShiftSrc1;
640 
641   // With multiple uses of the shift, this will duplicate the shift and
642   // increase register pressure.
643   //
644   // (build_vector_trunc (lshr_oneuse $src0, 16), (lshr_oneuse $src1, 16)
645   //  => (S_PACK_HH_B32_B16 $src0, $src1)
646   // (build_vector_trunc $src0, (lshr_oneuse SReg_32:$src1, 16))
647   //  => (S_PACK_LH_B32_B16 $src0, $src1)
648   // (build_vector_trunc $src0, $src1)
649   //  => (S_PACK_LL_B32_B16 $src0, $src1)
650 
651   bool Shift0 = mi_match(
652       Src0, *MRI, m_OneUse(m_GLShr(m_Reg(ShiftSrc0), m_SpecificICst(16))));
653 
654   bool Shift1 = mi_match(
655       Src1, *MRI, m_OneUse(m_GLShr(m_Reg(ShiftSrc1), m_SpecificICst(16))));
656 
657   unsigned Opc = AMDGPU::S_PACK_LL_B32_B16;
658   if (Shift0 && Shift1) {
659     Opc = AMDGPU::S_PACK_HH_B32_B16;
660     MI.getOperand(1).setReg(ShiftSrc0);
661     MI.getOperand(2).setReg(ShiftSrc1);
662   } else if (Shift1) {
663     Opc = AMDGPU::S_PACK_LH_B32_B16;
664     MI.getOperand(2).setReg(ShiftSrc1);
665   } else if (Shift0 && ConstSrc1 && ConstSrc1->Value == 0) {
666     // build_vector_trunc (lshr $src0, 16), 0 -> s_lshr_b32 $src0, 16
667     auto MIB = BuildMI(*BB, &MI, DL, TII.get(AMDGPU::S_LSHR_B32), Dst)
668       .addReg(ShiftSrc0)
669       .addImm(16);
670 
671     MI.eraseFromParent();
672     return constrainSelectedInstRegOperands(*MIB, TII, TRI, RBI);
673   }
674 
675   MI.setDesc(TII.get(Opc));
676   return constrainSelectedInstRegOperands(MI, TII, TRI, RBI);
677 }
678 
679 bool AMDGPUInstructionSelector::selectG_PTR_ADD(MachineInstr &I) const {
680   return selectG_ADD_SUB(I);
681 }
682 
683 bool AMDGPUInstructionSelector::selectG_IMPLICIT_DEF(MachineInstr &I) const {
684   const MachineOperand &MO = I.getOperand(0);
685 
686   // FIXME: Interface for getConstrainedRegClassForOperand needs work. The
687   // regbank check here is to know why getConstrainedRegClassForOperand failed.
688   const TargetRegisterClass *RC = TRI.getConstrainedRegClassForOperand(MO, *MRI);
689   if ((!RC && !MRI->getRegBankOrNull(MO.getReg())) ||
690       (RC && RBI.constrainGenericRegister(MO.getReg(), *RC, *MRI))) {
691     I.setDesc(TII.get(TargetOpcode::IMPLICIT_DEF));
692     return true;
693   }
694 
695   return false;
696 }
697 
698 bool AMDGPUInstructionSelector::selectG_INSERT(MachineInstr &I) const {
699   MachineBasicBlock *BB = I.getParent();
700 
701   Register DstReg = I.getOperand(0).getReg();
702   Register Src0Reg = I.getOperand(1).getReg();
703   Register Src1Reg = I.getOperand(2).getReg();
704   LLT Src1Ty = MRI->getType(Src1Reg);
705 
706   unsigned DstSize = MRI->getType(DstReg).getSizeInBits();
707   unsigned InsSize = Src1Ty.getSizeInBits();
708 
709   int64_t Offset = I.getOperand(3).getImm();
710 
711   // FIXME: These cases should have been illegal and unnecessary to check here.
712   if (Offset % 32 != 0 || InsSize % 32 != 0)
713     return false;
714 
715   // Currently not handled by getSubRegFromChannel.
716   if (InsSize > 128)
717     return false;
718 
719   unsigned SubReg = TRI.getSubRegFromChannel(Offset / 32, InsSize / 32);
720   if (SubReg == AMDGPU::NoSubRegister)
721     return false;
722 
723   const RegisterBank *DstBank = RBI.getRegBank(DstReg, *MRI, TRI);
724   const TargetRegisterClass *DstRC =
725     TRI.getRegClassForSizeOnBank(DstSize, *DstBank, *MRI);
726   if (!DstRC)
727     return false;
728 
729   const RegisterBank *Src0Bank = RBI.getRegBank(Src0Reg, *MRI, TRI);
730   const RegisterBank *Src1Bank = RBI.getRegBank(Src1Reg, *MRI, TRI);
731   const TargetRegisterClass *Src0RC =
732     TRI.getRegClassForSizeOnBank(DstSize, *Src0Bank, *MRI);
733   const TargetRegisterClass *Src1RC =
734     TRI.getRegClassForSizeOnBank(InsSize, *Src1Bank, *MRI);
735 
736   // Deal with weird cases where the class only partially supports the subreg
737   // index.
738   Src0RC = TRI.getSubClassWithSubReg(Src0RC, SubReg);
739   if (!Src0RC || !Src1RC)
740     return false;
741 
742   if (!RBI.constrainGenericRegister(DstReg, *DstRC, *MRI) ||
743       !RBI.constrainGenericRegister(Src0Reg, *Src0RC, *MRI) ||
744       !RBI.constrainGenericRegister(Src1Reg, *Src1RC, *MRI))
745     return false;
746 
747   const DebugLoc &DL = I.getDebugLoc();
748   BuildMI(*BB, &I, DL, TII.get(TargetOpcode::INSERT_SUBREG), DstReg)
749     .addReg(Src0Reg)
750     .addReg(Src1Reg)
751     .addImm(SubReg);
752 
753   I.eraseFromParent();
754   return true;
755 }
756 
757 bool AMDGPUInstructionSelector::selectG_SBFX_UBFX(MachineInstr &MI) const {
758   Register DstReg = MI.getOperand(0).getReg();
759   Register SrcReg = MI.getOperand(1).getReg();
760   Register OffsetReg = MI.getOperand(2).getReg();
761   Register WidthReg = MI.getOperand(3).getReg();
762 
763   assert(RBI.getRegBank(DstReg, *MRI, TRI)->getID() == AMDGPU::VGPRRegBankID &&
764          "scalar BFX instructions are expanded in regbankselect");
765   assert(MRI->getType(MI.getOperand(0).getReg()).getSizeInBits() == 32 &&
766          "64-bit vector BFX instructions are expanded in regbankselect");
767 
768   const DebugLoc &DL = MI.getDebugLoc();
769   MachineBasicBlock *MBB = MI.getParent();
770 
771   bool IsSigned = MI.getOpcode() == TargetOpcode::G_SBFX;
772   unsigned Opc = IsSigned ? AMDGPU::V_BFE_I32_e64 : AMDGPU::V_BFE_U32_e64;
773   auto MIB = BuildMI(*MBB, &MI, DL, TII.get(Opc), DstReg)
774                  .addReg(SrcReg)
775                  .addReg(OffsetReg)
776                  .addReg(WidthReg);
777   MI.eraseFromParent();
778   return constrainSelectedInstRegOperands(*MIB, TII, TRI, RBI);
779 }
780 
781 bool AMDGPUInstructionSelector::selectInterpP1F16(MachineInstr &MI) const {
782   if (STI.getLDSBankCount() != 16)
783     return selectImpl(MI, *CoverageInfo);
784 
785   Register Dst = MI.getOperand(0).getReg();
786   Register Src0 = MI.getOperand(2).getReg();
787   Register M0Val = MI.getOperand(6).getReg();
788   if (!RBI.constrainGenericRegister(M0Val, AMDGPU::SReg_32RegClass, *MRI) ||
789       !RBI.constrainGenericRegister(Dst, AMDGPU::VGPR_32RegClass, *MRI) ||
790       !RBI.constrainGenericRegister(Src0, AMDGPU::VGPR_32RegClass, *MRI))
791     return false;
792 
793   // This requires 2 instructions. It is possible to write a pattern to support
794   // this, but the generated isel emitter doesn't correctly deal with multiple
795   // output instructions using the same physical register input. The copy to m0
796   // is incorrectly placed before the second instruction.
797   //
798   // TODO: Match source modifiers.
799 
800   Register InterpMov = MRI->createVirtualRegister(&AMDGPU::VGPR_32RegClass);
801   const DebugLoc &DL = MI.getDebugLoc();
802   MachineBasicBlock *MBB = MI.getParent();
803 
804   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
805     .addReg(M0Val);
806   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::V_INTERP_MOV_F32), InterpMov)
807     .addImm(2)
808     .addImm(MI.getOperand(4).getImm())  // $attr
809     .addImm(MI.getOperand(3).getImm()); // $attrchan
810 
811   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::V_INTERP_P1LV_F16), Dst)
812     .addImm(0)                          // $src0_modifiers
813     .addReg(Src0)                       // $src0
814     .addImm(MI.getOperand(4).getImm())  // $attr
815     .addImm(MI.getOperand(3).getImm())  // $attrchan
816     .addImm(0)                          // $src2_modifiers
817     .addReg(InterpMov)                  // $src2 - 2 f16 values selected by high
818     .addImm(MI.getOperand(5).getImm())  // $high
819     .addImm(0)                          // $clamp
820     .addImm(0);                         // $omod
821 
822   MI.eraseFromParent();
823   return true;
824 }
825 
826 // Writelane is special in that it can use SGPR and M0 (which would normally
827 // count as using the constant bus twice - but in this case it is allowed since
828 // the lane selector doesn't count as a use of the constant bus). However, it is
829 // still required to abide by the 1 SGPR rule. Fix this up if we might have
830 // multiple SGPRs.
831 bool AMDGPUInstructionSelector::selectWritelane(MachineInstr &MI) const {
832   // With a constant bus limit of at least 2, there's no issue.
833   if (STI.getConstantBusLimit(AMDGPU::V_WRITELANE_B32) > 1)
834     return selectImpl(MI, *CoverageInfo);
835 
836   MachineBasicBlock *MBB = MI.getParent();
837   const DebugLoc &DL = MI.getDebugLoc();
838   Register VDst = MI.getOperand(0).getReg();
839   Register Val = MI.getOperand(2).getReg();
840   Register LaneSelect = MI.getOperand(3).getReg();
841   Register VDstIn = MI.getOperand(4).getReg();
842 
843   auto MIB = BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::V_WRITELANE_B32), VDst);
844 
845   Optional<ValueAndVReg> ConstSelect =
846       getIConstantVRegValWithLookThrough(LaneSelect, *MRI);
847   if (ConstSelect) {
848     // The selector has to be an inline immediate, so we can use whatever for
849     // the other operands.
850     MIB.addReg(Val);
851     MIB.addImm(ConstSelect->Value.getSExtValue() &
852                maskTrailingOnes<uint64_t>(STI.getWavefrontSizeLog2()));
853   } else {
854     Optional<ValueAndVReg> ConstVal =
855         getIConstantVRegValWithLookThrough(Val, *MRI);
856 
857     // If the value written is an inline immediate, we can get away without a
858     // copy to m0.
859     if (ConstVal && AMDGPU::isInlinableLiteral32(ConstVal->Value.getSExtValue(),
860                                                  STI.hasInv2PiInlineImm())) {
861       MIB.addImm(ConstVal->Value.getSExtValue());
862       MIB.addReg(LaneSelect);
863     } else {
864       MIB.addReg(Val);
865 
866       // If the lane selector was originally in a VGPR and copied with
867       // readfirstlane, there's a hazard to read the same SGPR from the
868       // VALU. Constrain to a different SGPR to help avoid needing a nop later.
869       RBI.constrainGenericRegister(LaneSelect, AMDGPU::SReg_32_XM0RegClass, *MRI);
870 
871       BuildMI(*MBB, *MIB, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
872         .addReg(LaneSelect);
873       MIB.addReg(AMDGPU::M0);
874     }
875   }
876 
877   MIB.addReg(VDstIn);
878 
879   MI.eraseFromParent();
880   return constrainSelectedInstRegOperands(*MIB, TII, TRI, RBI);
881 }
882 
883 // We need to handle this here because tablegen doesn't support matching
884 // instructions with multiple outputs.
885 bool AMDGPUInstructionSelector::selectDivScale(MachineInstr &MI) const {
886   Register Dst0 = MI.getOperand(0).getReg();
887   Register Dst1 = MI.getOperand(1).getReg();
888 
889   LLT Ty = MRI->getType(Dst0);
890   unsigned Opc;
891   if (Ty == LLT::scalar(32))
892     Opc = AMDGPU::V_DIV_SCALE_F32_e64;
893   else if (Ty == LLT::scalar(64))
894     Opc = AMDGPU::V_DIV_SCALE_F64_e64;
895   else
896     return false;
897 
898   // TODO: Match source modifiers.
899 
900   const DebugLoc &DL = MI.getDebugLoc();
901   MachineBasicBlock *MBB = MI.getParent();
902 
903   Register Numer = MI.getOperand(3).getReg();
904   Register Denom = MI.getOperand(4).getReg();
905   unsigned ChooseDenom = MI.getOperand(5).getImm();
906 
907   Register Src0 = ChooseDenom != 0 ? Numer : Denom;
908 
909   auto MIB = BuildMI(*MBB, &MI, DL, TII.get(Opc), Dst0)
910     .addDef(Dst1)
911     .addImm(0)     // $src0_modifiers
912     .addUse(Src0)  // $src0
913     .addImm(0)     // $src1_modifiers
914     .addUse(Denom) // $src1
915     .addImm(0)     // $src2_modifiers
916     .addUse(Numer) // $src2
917     .addImm(0)     // $clamp
918     .addImm(0);    // $omod
919 
920   MI.eraseFromParent();
921   return constrainSelectedInstRegOperands(*MIB, TII, TRI, RBI);
922 }
923 
924 bool AMDGPUInstructionSelector::selectG_INTRINSIC(MachineInstr &I) const {
925   unsigned IntrinsicID = I.getIntrinsicID();
926   switch (IntrinsicID) {
927   case Intrinsic::amdgcn_if_break: {
928     MachineBasicBlock *BB = I.getParent();
929 
930     // FIXME: Manually selecting to avoid dealing with the SReg_1 trick
931     // SelectionDAG uses for wave32 vs wave64.
932     BuildMI(*BB, &I, I.getDebugLoc(), TII.get(AMDGPU::SI_IF_BREAK))
933       .add(I.getOperand(0))
934       .add(I.getOperand(2))
935       .add(I.getOperand(3));
936 
937     Register DstReg = I.getOperand(0).getReg();
938     Register Src0Reg = I.getOperand(2).getReg();
939     Register Src1Reg = I.getOperand(3).getReg();
940 
941     I.eraseFromParent();
942 
943     for (Register Reg : { DstReg, Src0Reg, Src1Reg })
944       MRI->setRegClass(Reg, TRI.getWaveMaskRegClass());
945 
946     return true;
947   }
948   case Intrinsic::amdgcn_interp_p1_f16:
949     return selectInterpP1F16(I);
950   case Intrinsic::amdgcn_wqm:
951     return constrainCopyLikeIntrin(I, AMDGPU::WQM);
952   case Intrinsic::amdgcn_softwqm:
953     return constrainCopyLikeIntrin(I, AMDGPU::SOFT_WQM);
954   case Intrinsic::amdgcn_strict_wwm:
955   case Intrinsic::amdgcn_wwm:
956     return constrainCopyLikeIntrin(I, AMDGPU::STRICT_WWM);
957   case Intrinsic::amdgcn_strict_wqm:
958     return constrainCopyLikeIntrin(I, AMDGPU::STRICT_WQM);
959   case Intrinsic::amdgcn_writelane:
960     return selectWritelane(I);
961   case Intrinsic::amdgcn_div_scale:
962     return selectDivScale(I);
963   case Intrinsic::amdgcn_icmp:
964     return selectIntrinsicIcmp(I);
965   case Intrinsic::amdgcn_ballot:
966     return selectBallot(I);
967   case Intrinsic::amdgcn_reloc_constant:
968     return selectRelocConstant(I);
969   case Intrinsic::amdgcn_groupstaticsize:
970     return selectGroupStaticSize(I);
971   case Intrinsic::returnaddress:
972     return selectReturnAddress(I);
973   default:
974     return selectImpl(I, *CoverageInfo);
975   }
976 }
977 
978 static int getV_CMPOpcode(CmpInst::Predicate P, unsigned Size) {
979   if (Size != 32 && Size != 64)
980     return -1;
981   switch (P) {
982   default:
983     llvm_unreachable("Unknown condition code!");
984   case CmpInst::ICMP_NE:
985     return Size == 32 ? AMDGPU::V_CMP_NE_U32_e64 : AMDGPU::V_CMP_NE_U64_e64;
986   case CmpInst::ICMP_EQ:
987     return Size == 32 ? AMDGPU::V_CMP_EQ_U32_e64 : AMDGPU::V_CMP_EQ_U64_e64;
988   case CmpInst::ICMP_SGT:
989     return Size == 32 ? AMDGPU::V_CMP_GT_I32_e64 : AMDGPU::V_CMP_GT_I64_e64;
990   case CmpInst::ICMP_SGE:
991     return Size == 32 ? AMDGPU::V_CMP_GE_I32_e64 : AMDGPU::V_CMP_GE_I64_e64;
992   case CmpInst::ICMP_SLT:
993     return Size == 32 ? AMDGPU::V_CMP_LT_I32_e64 : AMDGPU::V_CMP_LT_I64_e64;
994   case CmpInst::ICMP_SLE:
995     return Size == 32 ? AMDGPU::V_CMP_LE_I32_e64 : AMDGPU::V_CMP_LE_I64_e64;
996   case CmpInst::ICMP_UGT:
997     return Size == 32 ? AMDGPU::V_CMP_GT_U32_e64 : AMDGPU::V_CMP_GT_U64_e64;
998   case CmpInst::ICMP_UGE:
999     return Size == 32 ? AMDGPU::V_CMP_GE_U32_e64 : AMDGPU::V_CMP_GE_U64_e64;
1000   case CmpInst::ICMP_ULT:
1001     return Size == 32 ? AMDGPU::V_CMP_LT_U32_e64 : AMDGPU::V_CMP_LT_U64_e64;
1002   case CmpInst::ICMP_ULE:
1003     return Size == 32 ? AMDGPU::V_CMP_LE_U32_e64 : AMDGPU::V_CMP_LE_U64_e64;
1004   }
1005 }
1006 
1007 int AMDGPUInstructionSelector::getS_CMPOpcode(CmpInst::Predicate P,
1008                                               unsigned Size) const {
1009   if (Size == 64) {
1010     if (!STI.hasScalarCompareEq64())
1011       return -1;
1012 
1013     switch (P) {
1014     case CmpInst::ICMP_NE:
1015       return AMDGPU::S_CMP_LG_U64;
1016     case CmpInst::ICMP_EQ:
1017       return AMDGPU::S_CMP_EQ_U64;
1018     default:
1019       return -1;
1020     }
1021   }
1022 
1023   if (Size != 32)
1024     return -1;
1025 
1026   switch (P) {
1027   case CmpInst::ICMP_NE:
1028     return AMDGPU::S_CMP_LG_U32;
1029   case CmpInst::ICMP_EQ:
1030     return AMDGPU::S_CMP_EQ_U32;
1031   case CmpInst::ICMP_SGT:
1032     return AMDGPU::S_CMP_GT_I32;
1033   case CmpInst::ICMP_SGE:
1034     return AMDGPU::S_CMP_GE_I32;
1035   case CmpInst::ICMP_SLT:
1036     return AMDGPU::S_CMP_LT_I32;
1037   case CmpInst::ICMP_SLE:
1038     return AMDGPU::S_CMP_LE_I32;
1039   case CmpInst::ICMP_UGT:
1040     return AMDGPU::S_CMP_GT_U32;
1041   case CmpInst::ICMP_UGE:
1042     return AMDGPU::S_CMP_GE_U32;
1043   case CmpInst::ICMP_ULT:
1044     return AMDGPU::S_CMP_LT_U32;
1045   case CmpInst::ICMP_ULE:
1046     return AMDGPU::S_CMP_LE_U32;
1047   default:
1048     llvm_unreachable("Unknown condition code!");
1049   }
1050 }
1051 
1052 bool AMDGPUInstructionSelector::selectG_ICMP(MachineInstr &I) const {
1053   MachineBasicBlock *BB = I.getParent();
1054   const DebugLoc &DL = I.getDebugLoc();
1055 
1056   Register SrcReg = I.getOperand(2).getReg();
1057   unsigned Size = RBI.getSizeInBits(SrcReg, *MRI, TRI);
1058 
1059   auto Pred = (CmpInst::Predicate)I.getOperand(1).getPredicate();
1060 
1061   Register CCReg = I.getOperand(0).getReg();
1062   if (!isVCC(CCReg, *MRI)) {
1063     int Opcode = getS_CMPOpcode(Pred, Size);
1064     if (Opcode == -1)
1065       return false;
1066     MachineInstr *ICmp = BuildMI(*BB, &I, DL, TII.get(Opcode))
1067             .add(I.getOperand(2))
1068             .add(I.getOperand(3));
1069     BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), CCReg)
1070       .addReg(AMDGPU::SCC);
1071     bool Ret =
1072         constrainSelectedInstRegOperands(*ICmp, TII, TRI, RBI) &&
1073         RBI.constrainGenericRegister(CCReg, AMDGPU::SReg_32RegClass, *MRI);
1074     I.eraseFromParent();
1075     return Ret;
1076   }
1077 
1078   int Opcode = getV_CMPOpcode(Pred, Size);
1079   if (Opcode == -1)
1080     return false;
1081 
1082   MachineInstr *ICmp = BuildMI(*BB, &I, DL, TII.get(Opcode),
1083             I.getOperand(0).getReg())
1084             .add(I.getOperand(2))
1085             .add(I.getOperand(3));
1086   RBI.constrainGenericRegister(ICmp->getOperand(0).getReg(),
1087                                *TRI.getBoolRC(), *MRI);
1088   bool Ret = constrainSelectedInstRegOperands(*ICmp, TII, TRI, RBI);
1089   I.eraseFromParent();
1090   return Ret;
1091 }
1092 
1093 bool AMDGPUInstructionSelector::selectIntrinsicIcmp(MachineInstr &I) const {
1094   Register Dst = I.getOperand(0).getReg();
1095   if (isVCC(Dst, *MRI))
1096     return false;
1097 
1098   if (MRI->getType(Dst).getSizeInBits() != STI.getWavefrontSize())
1099     return false;
1100 
1101   MachineBasicBlock *BB = I.getParent();
1102   const DebugLoc &DL = I.getDebugLoc();
1103   Register SrcReg = I.getOperand(2).getReg();
1104   unsigned Size = RBI.getSizeInBits(SrcReg, *MRI, TRI);
1105   auto Pred = static_cast<CmpInst::Predicate>(I.getOperand(4).getImm());
1106 
1107   int Opcode = getV_CMPOpcode(Pred, Size);
1108   if (Opcode == -1)
1109     return false;
1110 
1111   MachineInstr *ICmp = BuildMI(*BB, &I, DL, TII.get(Opcode), Dst)
1112                            .add(I.getOperand(2))
1113                            .add(I.getOperand(3));
1114   RBI.constrainGenericRegister(ICmp->getOperand(0).getReg(), *TRI.getBoolRC(),
1115                                *MRI);
1116   bool Ret = constrainSelectedInstRegOperands(*ICmp, TII, TRI, RBI);
1117   I.eraseFromParent();
1118   return Ret;
1119 }
1120 
1121 bool AMDGPUInstructionSelector::selectBallot(MachineInstr &I) const {
1122   MachineBasicBlock *BB = I.getParent();
1123   const DebugLoc &DL = I.getDebugLoc();
1124   Register DstReg = I.getOperand(0).getReg();
1125   const unsigned Size = MRI->getType(DstReg).getSizeInBits();
1126   const bool Is64 = Size == 64;
1127 
1128   if (Size != STI.getWavefrontSize())
1129     return false;
1130 
1131   Optional<ValueAndVReg> Arg =
1132       getIConstantVRegValWithLookThrough(I.getOperand(2).getReg(), *MRI);
1133 
1134   if (Arg.hasValue()) {
1135     const int64_t Value = Arg.getValue().Value.getSExtValue();
1136     if (Value == 0) {
1137       unsigned Opcode = Is64 ? AMDGPU::S_MOV_B64 : AMDGPU::S_MOV_B32;
1138       BuildMI(*BB, &I, DL, TII.get(Opcode), DstReg).addImm(0);
1139     } else if (Value == -1) { // all ones
1140       Register SrcReg = Is64 ? AMDGPU::EXEC : AMDGPU::EXEC_LO;
1141       BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), DstReg).addReg(SrcReg);
1142     } else
1143       return false;
1144   } else {
1145     Register SrcReg = I.getOperand(2).getReg();
1146     BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), DstReg).addReg(SrcReg);
1147   }
1148 
1149   I.eraseFromParent();
1150   return true;
1151 }
1152 
1153 bool AMDGPUInstructionSelector::selectRelocConstant(MachineInstr &I) const {
1154   Register DstReg = I.getOperand(0).getReg();
1155   const RegisterBank *DstBank = RBI.getRegBank(DstReg, *MRI, TRI);
1156   const TargetRegisterClass *DstRC =
1157     TRI.getRegClassForSizeOnBank(32, *DstBank, *MRI);
1158   if (!DstRC || !RBI.constrainGenericRegister(DstReg, *DstRC, *MRI))
1159     return false;
1160 
1161   const bool IsVALU = DstBank->getID() == AMDGPU::VGPRRegBankID;
1162 
1163   Module *M = MF->getFunction().getParent();
1164   const MDNode *Metadata = I.getOperand(2).getMetadata();
1165   auto SymbolName = cast<MDString>(Metadata->getOperand(0))->getString();
1166   auto RelocSymbol = cast<GlobalVariable>(
1167     M->getOrInsertGlobal(SymbolName, Type::getInt32Ty(M->getContext())));
1168 
1169   MachineBasicBlock *BB = I.getParent();
1170   BuildMI(*BB, &I, I.getDebugLoc(),
1171           TII.get(IsVALU ? AMDGPU::V_MOV_B32_e32 : AMDGPU::S_MOV_B32), DstReg)
1172     .addGlobalAddress(RelocSymbol, 0, SIInstrInfo::MO_ABS32_LO);
1173 
1174   I.eraseFromParent();
1175   return true;
1176 }
1177 
1178 bool AMDGPUInstructionSelector::selectGroupStaticSize(MachineInstr &I) const {
1179   Triple::OSType OS = MF->getTarget().getTargetTriple().getOS();
1180 
1181   Register DstReg = I.getOperand(0).getReg();
1182   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
1183   unsigned Mov = DstRB->getID() == AMDGPU::SGPRRegBankID ?
1184     AMDGPU::S_MOV_B32 : AMDGPU::V_MOV_B32_e32;
1185 
1186   MachineBasicBlock *MBB = I.getParent();
1187   const DebugLoc &DL = I.getDebugLoc();
1188 
1189   auto MIB = BuildMI(*MBB, &I, DL, TII.get(Mov), DstReg);
1190 
1191   if (OS == Triple::AMDHSA || OS == Triple::AMDPAL) {
1192     const SIMachineFunctionInfo *MFI = MF->getInfo<SIMachineFunctionInfo>();
1193     MIB.addImm(MFI->getLDSSize());
1194   } else {
1195     Module *M = MF->getFunction().getParent();
1196     const GlobalValue *GV
1197       = Intrinsic::getDeclaration(M, Intrinsic::amdgcn_groupstaticsize);
1198     MIB.addGlobalAddress(GV, 0, SIInstrInfo::MO_ABS32_LO);
1199   }
1200 
1201   I.eraseFromParent();
1202   return constrainSelectedInstRegOperands(*MIB, TII, TRI, RBI);
1203 }
1204 
1205 bool AMDGPUInstructionSelector::selectReturnAddress(MachineInstr &I) const {
1206   MachineBasicBlock *MBB = I.getParent();
1207   MachineFunction &MF = *MBB->getParent();
1208   const DebugLoc &DL = I.getDebugLoc();
1209 
1210   MachineOperand &Dst = I.getOperand(0);
1211   Register DstReg = Dst.getReg();
1212   unsigned Depth = I.getOperand(2).getImm();
1213 
1214   const TargetRegisterClass *RC
1215     = TRI.getConstrainedRegClassForOperand(Dst, *MRI);
1216   if (!RC->hasSubClassEq(&AMDGPU::SGPR_64RegClass) ||
1217       !RBI.constrainGenericRegister(DstReg, *RC, *MRI))
1218     return false;
1219 
1220   // Check for kernel and shader functions
1221   if (Depth != 0 ||
1222       MF.getInfo<SIMachineFunctionInfo>()->isEntryFunction()) {
1223     BuildMI(*MBB, &I, DL, TII.get(AMDGPU::S_MOV_B64), DstReg)
1224       .addImm(0);
1225     I.eraseFromParent();
1226     return true;
1227   }
1228 
1229   MachineFrameInfo &MFI = MF.getFrameInfo();
1230   // There is a call to @llvm.returnaddress in this function
1231   MFI.setReturnAddressIsTaken(true);
1232 
1233   // Get the return address reg and mark it as an implicit live-in
1234   Register ReturnAddrReg = TRI.getReturnAddressReg(MF);
1235   Register LiveIn = getFunctionLiveInPhysReg(MF, TII, ReturnAddrReg,
1236                                              AMDGPU::SReg_64RegClass, DL);
1237   BuildMI(*MBB, &I, DL, TII.get(AMDGPU::COPY), DstReg)
1238     .addReg(LiveIn);
1239   I.eraseFromParent();
1240   return true;
1241 }
1242 
1243 bool AMDGPUInstructionSelector::selectEndCfIntrinsic(MachineInstr &MI) const {
1244   // FIXME: Manually selecting to avoid dealing with the SReg_1 trick
1245   // SelectionDAG uses for wave32 vs wave64.
1246   MachineBasicBlock *BB = MI.getParent();
1247   BuildMI(*BB, &MI, MI.getDebugLoc(), TII.get(AMDGPU::SI_END_CF))
1248       .add(MI.getOperand(1));
1249 
1250   Register Reg = MI.getOperand(1).getReg();
1251   MI.eraseFromParent();
1252 
1253   if (!MRI->getRegClassOrNull(Reg))
1254     MRI->setRegClass(Reg, TRI.getWaveMaskRegClass());
1255   return true;
1256 }
1257 
1258 bool AMDGPUInstructionSelector::selectDSOrderedIntrinsic(
1259   MachineInstr &MI, Intrinsic::ID IntrID) const {
1260   MachineBasicBlock *MBB = MI.getParent();
1261   MachineFunction *MF = MBB->getParent();
1262   const DebugLoc &DL = MI.getDebugLoc();
1263 
1264   unsigned IndexOperand = MI.getOperand(7).getImm();
1265   bool WaveRelease = MI.getOperand(8).getImm() != 0;
1266   bool WaveDone = MI.getOperand(9).getImm() != 0;
1267 
1268   if (WaveDone && !WaveRelease)
1269     report_fatal_error("ds_ordered_count: wave_done requires wave_release");
1270 
1271   unsigned OrderedCountIndex = IndexOperand & 0x3f;
1272   IndexOperand &= ~0x3f;
1273   unsigned CountDw = 0;
1274 
1275   if (STI.getGeneration() >= AMDGPUSubtarget::GFX10) {
1276     CountDw = (IndexOperand >> 24) & 0xf;
1277     IndexOperand &= ~(0xf << 24);
1278 
1279     if (CountDw < 1 || CountDw > 4) {
1280       report_fatal_error(
1281         "ds_ordered_count: dword count must be between 1 and 4");
1282     }
1283   }
1284 
1285   if (IndexOperand)
1286     report_fatal_error("ds_ordered_count: bad index operand");
1287 
1288   unsigned Instruction = IntrID == Intrinsic::amdgcn_ds_ordered_add ? 0 : 1;
1289   unsigned ShaderType = SIInstrInfo::getDSShaderTypeValue(*MF);
1290 
1291   unsigned Offset0 = OrderedCountIndex << 2;
1292   unsigned Offset1 = WaveRelease | (WaveDone << 1) | (ShaderType << 2) |
1293                      (Instruction << 4);
1294 
1295   if (STI.getGeneration() >= AMDGPUSubtarget::GFX10)
1296     Offset1 |= (CountDw - 1) << 6;
1297 
1298   unsigned Offset = Offset0 | (Offset1 << 8);
1299 
1300   Register M0Val = MI.getOperand(2).getReg();
1301   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1302     .addReg(M0Val);
1303 
1304   Register DstReg = MI.getOperand(0).getReg();
1305   Register ValReg = MI.getOperand(3).getReg();
1306   MachineInstrBuilder DS =
1307     BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::DS_ORDERED_COUNT), DstReg)
1308       .addReg(ValReg)
1309       .addImm(Offset)
1310       .cloneMemRefs(MI);
1311 
1312   if (!RBI.constrainGenericRegister(M0Val, AMDGPU::SReg_32RegClass, *MRI))
1313     return false;
1314 
1315   bool Ret = constrainSelectedInstRegOperands(*DS, TII, TRI, RBI);
1316   MI.eraseFromParent();
1317   return Ret;
1318 }
1319 
1320 static unsigned gwsIntrinToOpcode(unsigned IntrID) {
1321   switch (IntrID) {
1322   case Intrinsic::amdgcn_ds_gws_init:
1323     return AMDGPU::DS_GWS_INIT;
1324   case Intrinsic::amdgcn_ds_gws_barrier:
1325     return AMDGPU::DS_GWS_BARRIER;
1326   case Intrinsic::amdgcn_ds_gws_sema_v:
1327     return AMDGPU::DS_GWS_SEMA_V;
1328   case Intrinsic::amdgcn_ds_gws_sema_br:
1329     return AMDGPU::DS_GWS_SEMA_BR;
1330   case Intrinsic::amdgcn_ds_gws_sema_p:
1331     return AMDGPU::DS_GWS_SEMA_P;
1332   case Intrinsic::amdgcn_ds_gws_sema_release_all:
1333     return AMDGPU::DS_GWS_SEMA_RELEASE_ALL;
1334   default:
1335     llvm_unreachable("not a gws intrinsic");
1336   }
1337 }
1338 
1339 bool AMDGPUInstructionSelector::selectDSGWSIntrinsic(MachineInstr &MI,
1340                                                      Intrinsic::ID IID) const {
1341   if (IID == Intrinsic::amdgcn_ds_gws_sema_release_all &&
1342       !STI.hasGWSSemaReleaseAll())
1343     return false;
1344 
1345   // intrinsic ID, vsrc, offset
1346   const bool HasVSrc = MI.getNumOperands() == 3;
1347   assert(HasVSrc || MI.getNumOperands() == 2);
1348 
1349   Register BaseOffset = MI.getOperand(HasVSrc ? 2 : 1).getReg();
1350   const RegisterBank *OffsetRB = RBI.getRegBank(BaseOffset, *MRI, TRI);
1351   if (OffsetRB->getID() != AMDGPU::SGPRRegBankID)
1352     return false;
1353 
1354   MachineInstr *OffsetDef = getDefIgnoringCopies(BaseOffset, *MRI);
1355   assert(OffsetDef);
1356 
1357   unsigned ImmOffset;
1358 
1359   MachineBasicBlock *MBB = MI.getParent();
1360   const DebugLoc &DL = MI.getDebugLoc();
1361 
1362   MachineInstr *Readfirstlane = nullptr;
1363 
1364   // If we legalized the VGPR input, strip out the readfirstlane to analyze the
1365   // incoming offset, in case there's an add of a constant. We'll have to put it
1366   // back later.
1367   if (OffsetDef->getOpcode() == AMDGPU::V_READFIRSTLANE_B32) {
1368     Readfirstlane = OffsetDef;
1369     BaseOffset = OffsetDef->getOperand(1).getReg();
1370     OffsetDef = getDefIgnoringCopies(BaseOffset, *MRI);
1371   }
1372 
1373   if (OffsetDef->getOpcode() == AMDGPU::G_CONSTANT) {
1374     // If we have a constant offset, try to use the 0 in m0 as the base.
1375     // TODO: Look into changing the default m0 initialization value. If the
1376     // default -1 only set the low 16-bits, we could leave it as-is and add 1 to
1377     // the immediate offset.
1378 
1379     ImmOffset = OffsetDef->getOperand(1).getCImm()->getZExtValue();
1380     BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::S_MOV_B32), AMDGPU::M0)
1381       .addImm(0);
1382   } else {
1383     std::tie(BaseOffset, ImmOffset) =
1384         AMDGPU::getBaseWithConstantOffset(*MRI, BaseOffset);
1385 
1386     if (Readfirstlane) {
1387       // We have the constant offset now, so put the readfirstlane back on the
1388       // variable component.
1389       if (!RBI.constrainGenericRegister(BaseOffset, AMDGPU::VGPR_32RegClass, *MRI))
1390         return false;
1391 
1392       Readfirstlane->getOperand(1).setReg(BaseOffset);
1393       BaseOffset = Readfirstlane->getOperand(0).getReg();
1394     } else {
1395       if (!RBI.constrainGenericRegister(BaseOffset,
1396                                         AMDGPU::SReg_32RegClass, *MRI))
1397         return false;
1398     }
1399 
1400     Register M0Base = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1401     BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::S_LSHL_B32), M0Base)
1402       .addReg(BaseOffset)
1403       .addImm(16);
1404 
1405     BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1406       .addReg(M0Base);
1407   }
1408 
1409   // The resource id offset is computed as (<isa opaque base> + M0[21:16] +
1410   // offset field) % 64. Some versions of the programming guide omit the m0
1411   // part, or claim it's from offset 0.
1412   auto MIB = BuildMI(*MBB, &MI, DL, TII.get(gwsIntrinToOpcode(IID)));
1413 
1414   if (HasVSrc) {
1415     Register VSrc = MI.getOperand(1).getReg();
1416 
1417     if (STI.needsAlignedVGPRs()) {
1418       // Add implicit aligned super-reg to force alignment on the data operand.
1419       Register Undef = MRI->createVirtualRegister(&AMDGPU::VGPR_32RegClass);
1420       BuildMI(*MBB, &*MIB, DL, TII.get(AMDGPU::IMPLICIT_DEF), Undef);
1421       Register NewVR =
1422           MRI->createVirtualRegister(&AMDGPU::VReg_64_Align2RegClass);
1423       BuildMI(*MBB, &*MIB, DL, TII.get(AMDGPU::REG_SEQUENCE), NewVR)
1424           .addReg(VSrc, 0, MI.getOperand(1).getSubReg())
1425           .addImm(AMDGPU::sub0)
1426           .addReg(Undef)
1427           .addImm(AMDGPU::sub1);
1428       MIB.addReg(NewVR, 0, AMDGPU::sub0);
1429       MIB.addReg(NewVR, RegState::Implicit);
1430     } else {
1431       MIB.addReg(VSrc);
1432     }
1433 
1434     if (!RBI.constrainGenericRegister(VSrc, AMDGPU::VGPR_32RegClass, *MRI))
1435       return false;
1436   }
1437 
1438   MIB.addImm(ImmOffset)
1439      .cloneMemRefs(MI);
1440 
1441   MI.eraseFromParent();
1442   return true;
1443 }
1444 
1445 bool AMDGPUInstructionSelector::selectDSAppendConsume(MachineInstr &MI,
1446                                                       bool IsAppend) const {
1447   Register PtrBase = MI.getOperand(2).getReg();
1448   LLT PtrTy = MRI->getType(PtrBase);
1449   bool IsGDS = PtrTy.getAddressSpace() == AMDGPUAS::REGION_ADDRESS;
1450 
1451   unsigned Offset;
1452   std::tie(PtrBase, Offset) = selectDS1Addr1OffsetImpl(MI.getOperand(2));
1453 
1454   // TODO: Should this try to look through readfirstlane like GWS?
1455   if (!isDSOffsetLegal(PtrBase, Offset)) {
1456     PtrBase = MI.getOperand(2).getReg();
1457     Offset = 0;
1458   }
1459 
1460   MachineBasicBlock *MBB = MI.getParent();
1461   const DebugLoc &DL = MI.getDebugLoc();
1462   const unsigned Opc = IsAppend ? AMDGPU::DS_APPEND : AMDGPU::DS_CONSUME;
1463 
1464   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1465     .addReg(PtrBase);
1466   if (!RBI.constrainGenericRegister(PtrBase, AMDGPU::SReg_32RegClass, *MRI))
1467     return false;
1468 
1469   auto MIB = BuildMI(*MBB, &MI, DL, TII.get(Opc), MI.getOperand(0).getReg())
1470     .addImm(Offset)
1471     .addImm(IsGDS ? -1 : 0)
1472     .cloneMemRefs(MI);
1473   MI.eraseFromParent();
1474   return constrainSelectedInstRegOperands(*MIB, TII, TRI, RBI);
1475 }
1476 
1477 bool AMDGPUInstructionSelector::selectSBarrier(MachineInstr &MI) const {
1478   if (TM.getOptLevel() > CodeGenOpt::None) {
1479     unsigned WGSize = STI.getFlatWorkGroupSizes(MF->getFunction()).second;
1480     if (WGSize <= STI.getWavefrontSize()) {
1481       MachineBasicBlock *MBB = MI.getParent();
1482       const DebugLoc &DL = MI.getDebugLoc();
1483       BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::WAVE_BARRIER));
1484       MI.eraseFromParent();
1485       return true;
1486     }
1487   }
1488   return selectImpl(MI, *CoverageInfo);
1489 }
1490 
1491 static bool parseTexFail(uint64_t TexFailCtrl, bool &TFE, bool &LWE,
1492                          bool &IsTexFail) {
1493   if (TexFailCtrl)
1494     IsTexFail = true;
1495 
1496   TFE = (TexFailCtrl & 0x1) ? true : false;
1497   TexFailCtrl &= ~(uint64_t)0x1;
1498   LWE = (TexFailCtrl & 0x2) ? true : false;
1499   TexFailCtrl &= ~(uint64_t)0x2;
1500 
1501   return TexFailCtrl == 0;
1502 }
1503 
1504 bool AMDGPUInstructionSelector::selectImageIntrinsic(
1505   MachineInstr &MI, const AMDGPU::ImageDimIntrinsicInfo *Intr) const {
1506   MachineBasicBlock *MBB = MI.getParent();
1507   const DebugLoc &DL = MI.getDebugLoc();
1508 
1509   const AMDGPU::MIMGBaseOpcodeInfo *BaseOpcode =
1510     AMDGPU::getMIMGBaseOpcodeInfo(Intr->BaseOpcode);
1511 
1512   const AMDGPU::MIMGDimInfo *DimInfo = AMDGPU::getMIMGDimInfo(Intr->Dim);
1513   const AMDGPU::MIMGLZMappingInfo *LZMappingInfo =
1514       AMDGPU::getMIMGLZMappingInfo(Intr->BaseOpcode);
1515   const AMDGPU::MIMGMIPMappingInfo *MIPMappingInfo =
1516       AMDGPU::getMIMGMIPMappingInfo(Intr->BaseOpcode);
1517   unsigned IntrOpcode = Intr->BaseOpcode;
1518   const bool IsGFX10Plus = AMDGPU::isGFX10Plus(STI);
1519 
1520   const unsigned ArgOffset = MI.getNumExplicitDefs() + 1;
1521 
1522   Register VDataIn, VDataOut;
1523   LLT VDataTy;
1524   int NumVDataDwords = -1;
1525   bool IsD16 = MI.getOpcode() == AMDGPU::G_AMDGPU_INTRIN_IMAGE_LOAD_D16 ||
1526                MI.getOpcode() == AMDGPU::G_AMDGPU_INTRIN_IMAGE_STORE_D16;
1527 
1528   bool Unorm;
1529   if (!BaseOpcode->Sampler)
1530     Unorm = true;
1531   else
1532     Unorm = MI.getOperand(ArgOffset + Intr->UnormIndex).getImm() != 0;
1533 
1534   bool TFE;
1535   bool LWE;
1536   bool IsTexFail = false;
1537   if (!parseTexFail(MI.getOperand(ArgOffset + Intr->TexFailCtrlIndex).getImm(),
1538                     TFE, LWE, IsTexFail))
1539     return false;
1540 
1541   const int Flags = MI.getOperand(ArgOffset + Intr->NumArgs).getImm();
1542   const bool IsA16 = (Flags & 1) != 0;
1543   const bool IsG16 = (Flags & 2) != 0;
1544 
1545   // A16 implies 16 bit gradients if subtarget doesn't support G16
1546   if (IsA16 && !STI.hasG16() && !IsG16)
1547     return false;
1548 
1549   unsigned DMask = 0;
1550   unsigned DMaskLanes = 0;
1551 
1552   if (BaseOpcode->Atomic) {
1553     VDataOut = MI.getOperand(0).getReg();
1554     VDataIn = MI.getOperand(2).getReg();
1555     LLT Ty = MRI->getType(VDataIn);
1556 
1557     // Be careful to allow atomic swap on 16-bit element vectors.
1558     const bool Is64Bit = BaseOpcode->AtomicX2 ?
1559       Ty.getSizeInBits() == 128 :
1560       Ty.getSizeInBits() == 64;
1561 
1562     if (BaseOpcode->AtomicX2) {
1563       assert(MI.getOperand(3).getReg() == AMDGPU::NoRegister);
1564 
1565       DMask = Is64Bit ? 0xf : 0x3;
1566       NumVDataDwords = Is64Bit ? 4 : 2;
1567     } else {
1568       DMask = Is64Bit ? 0x3 : 0x1;
1569       NumVDataDwords = Is64Bit ? 2 : 1;
1570     }
1571   } else {
1572     DMask = MI.getOperand(ArgOffset + Intr->DMaskIndex).getImm();
1573     DMaskLanes = BaseOpcode->Gather4 ? 4 : countPopulation(DMask);
1574 
1575     if (BaseOpcode->Store) {
1576       VDataIn = MI.getOperand(1).getReg();
1577       VDataTy = MRI->getType(VDataIn);
1578       NumVDataDwords = (VDataTy.getSizeInBits() + 31) / 32;
1579     } else {
1580       VDataOut = MI.getOperand(0).getReg();
1581       VDataTy = MRI->getType(VDataOut);
1582       NumVDataDwords = DMaskLanes;
1583 
1584       if (IsD16 && !STI.hasUnpackedD16VMem())
1585         NumVDataDwords = (DMaskLanes + 1) / 2;
1586     }
1587   }
1588 
1589   // Optimize _L to _LZ when _L is zero
1590   if (LZMappingInfo) {
1591     // The legalizer replaced the register with an immediate 0 if we need to
1592     // change the opcode.
1593     const MachineOperand &Lod = MI.getOperand(ArgOffset + Intr->LodIndex);
1594     if (Lod.isImm()) {
1595       assert(Lod.getImm() == 0);
1596       IntrOpcode = LZMappingInfo->LZ;  // set new opcode to _lz variant of _l
1597     }
1598   }
1599 
1600   // Optimize _mip away, when 'lod' is zero
1601   if (MIPMappingInfo) {
1602     const MachineOperand &Lod = MI.getOperand(ArgOffset + Intr->MipIndex);
1603     if (Lod.isImm()) {
1604       assert(Lod.getImm() == 0);
1605       IntrOpcode = MIPMappingInfo->NONMIP;  // set new opcode to variant without _mip
1606     }
1607   }
1608 
1609   // Set G16 opcode
1610   if (IsG16 && !IsA16) {
1611     const AMDGPU::MIMGG16MappingInfo *G16MappingInfo =
1612         AMDGPU::getMIMGG16MappingInfo(Intr->BaseOpcode);
1613     assert(G16MappingInfo);
1614     IntrOpcode = G16MappingInfo->G16; // set opcode to variant with _g16
1615   }
1616 
1617   // TODO: Check this in verifier.
1618   assert((!IsTexFail || DMaskLanes >= 1) && "should have legalized this");
1619 
1620   unsigned CPol = MI.getOperand(ArgOffset + Intr->CachePolicyIndex).getImm();
1621   if (BaseOpcode->Atomic)
1622     CPol |= AMDGPU::CPol::GLC; // TODO no-return optimization
1623   if (CPol & ~AMDGPU::CPol::ALL)
1624     return false;
1625 
1626   int NumVAddrRegs = 0;
1627   int NumVAddrDwords = 0;
1628   for (unsigned I = Intr->VAddrStart; I < Intr->VAddrEnd; I++) {
1629     // Skip the $noregs and 0s inserted during legalization.
1630     MachineOperand &AddrOp = MI.getOperand(ArgOffset + I);
1631     if (!AddrOp.isReg())
1632       continue; // XXX - Break?
1633 
1634     Register Addr = AddrOp.getReg();
1635     if (!Addr)
1636       break;
1637 
1638     ++NumVAddrRegs;
1639     NumVAddrDwords += (MRI->getType(Addr).getSizeInBits() + 31) / 32;
1640   }
1641 
1642   // The legalizer preprocessed the intrinsic arguments. If we aren't using
1643   // NSA, these should have beeen packed into a single value in the first
1644   // address register
1645   const bool UseNSA = NumVAddrRegs != 1 && NumVAddrDwords == NumVAddrRegs;
1646   if (UseNSA && !STI.hasFeature(AMDGPU::FeatureNSAEncoding)) {
1647     LLVM_DEBUG(dbgs() << "Trying to use NSA on non-NSA target\n");
1648     return false;
1649   }
1650 
1651   if (IsTexFail)
1652     ++NumVDataDwords;
1653 
1654   int Opcode = -1;
1655   if (IsGFX10Plus) {
1656     Opcode = AMDGPU::getMIMGOpcode(IntrOpcode,
1657                                    UseNSA ? AMDGPU::MIMGEncGfx10NSA
1658                                           : AMDGPU::MIMGEncGfx10Default,
1659                                    NumVDataDwords, NumVAddrDwords);
1660   } else {
1661     if (STI.getGeneration() >= AMDGPUSubtarget::VOLCANIC_ISLANDS)
1662       Opcode = AMDGPU::getMIMGOpcode(IntrOpcode, AMDGPU::MIMGEncGfx8,
1663                                      NumVDataDwords, NumVAddrDwords);
1664     if (Opcode == -1)
1665       Opcode = AMDGPU::getMIMGOpcode(IntrOpcode, AMDGPU::MIMGEncGfx6,
1666                                      NumVDataDwords, NumVAddrDwords);
1667   }
1668   assert(Opcode != -1);
1669 
1670   auto MIB = BuildMI(*MBB, &MI, DL, TII.get(Opcode))
1671     .cloneMemRefs(MI);
1672 
1673   if (VDataOut) {
1674     if (BaseOpcode->AtomicX2) {
1675       const bool Is64 = MRI->getType(VDataOut).getSizeInBits() == 64;
1676 
1677       Register TmpReg = MRI->createVirtualRegister(
1678         Is64 ? &AMDGPU::VReg_128RegClass : &AMDGPU::VReg_64RegClass);
1679       unsigned SubReg = Is64 ? AMDGPU::sub0_sub1 : AMDGPU::sub0;
1680 
1681       MIB.addDef(TmpReg);
1682       if (!MRI->use_empty(VDataOut)) {
1683         BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), VDataOut)
1684             .addReg(TmpReg, RegState::Kill, SubReg);
1685       }
1686 
1687     } else {
1688       MIB.addDef(VDataOut); // vdata output
1689     }
1690   }
1691 
1692   if (VDataIn)
1693     MIB.addReg(VDataIn); // vdata input
1694 
1695   for (int I = 0; I != NumVAddrRegs; ++I) {
1696     MachineOperand &SrcOp = MI.getOperand(ArgOffset + Intr->VAddrStart + I);
1697     if (SrcOp.isReg()) {
1698       assert(SrcOp.getReg() != 0);
1699       MIB.addReg(SrcOp.getReg());
1700     }
1701   }
1702 
1703   MIB.addReg(MI.getOperand(ArgOffset + Intr->RsrcIndex).getReg());
1704   if (BaseOpcode->Sampler)
1705     MIB.addReg(MI.getOperand(ArgOffset + Intr->SampIndex).getReg());
1706 
1707   MIB.addImm(DMask); // dmask
1708 
1709   if (IsGFX10Plus)
1710     MIB.addImm(DimInfo->Encoding);
1711   MIB.addImm(Unorm);
1712 
1713   MIB.addImm(CPol);
1714   MIB.addImm(IsA16 &&  // a16 or r128
1715              STI.hasFeature(AMDGPU::FeatureR128A16) ? -1 : 0);
1716   if (IsGFX10Plus)
1717     MIB.addImm(IsA16 ? -1 : 0);
1718 
1719   MIB.addImm(TFE); // tfe
1720   MIB.addImm(LWE); // lwe
1721   if (!IsGFX10Plus)
1722     MIB.addImm(DimInfo->DA ? -1 : 0);
1723   if (BaseOpcode->HasD16)
1724     MIB.addImm(IsD16 ? -1 : 0);
1725 
1726   if (IsTexFail) {
1727     // An image load instruction with TFE/LWE only conditionally writes to its
1728     // result registers. Initialize them to zero so that we always get well
1729     // defined result values.
1730     assert(VDataOut && !VDataIn);
1731     Register Tied = MRI->cloneVirtualRegister(VDataOut);
1732     Register Zero = MRI->createVirtualRegister(&AMDGPU::VGPR_32RegClass);
1733     BuildMI(*MBB, *MIB, DL, TII.get(AMDGPU::V_MOV_B32_e32), Zero)
1734       .addImm(0);
1735     auto Parts = TRI.getRegSplitParts(MRI->getRegClass(Tied), 4);
1736     if (STI.usePRTStrictNull()) {
1737       // With enable-prt-strict-null enabled, initialize all result registers to
1738       // zero.
1739       auto RegSeq =
1740           BuildMI(*MBB, *MIB, DL, TII.get(AMDGPU::REG_SEQUENCE), Tied);
1741       for (auto Sub : Parts)
1742         RegSeq.addReg(Zero).addImm(Sub);
1743     } else {
1744       // With enable-prt-strict-null disabled, only initialize the extra TFE/LWE
1745       // result register.
1746       Register Undef = MRI->createVirtualRegister(&AMDGPU::VGPR_32RegClass);
1747       BuildMI(*MBB, *MIB, DL, TII.get(AMDGPU::IMPLICIT_DEF), Undef);
1748       auto RegSeq =
1749           BuildMI(*MBB, *MIB, DL, TII.get(AMDGPU::REG_SEQUENCE), Tied);
1750       for (auto Sub : Parts.drop_back(1))
1751         RegSeq.addReg(Undef).addImm(Sub);
1752       RegSeq.addReg(Zero).addImm(Parts.back());
1753     }
1754     MIB.addReg(Tied, RegState::Implicit);
1755     MIB->tieOperands(0, MIB->getNumOperands() - 1);
1756   }
1757 
1758   MI.eraseFromParent();
1759   return constrainSelectedInstRegOperands(*MIB, TII, TRI, RBI);
1760 }
1761 
1762 bool AMDGPUInstructionSelector::selectG_INTRINSIC_W_SIDE_EFFECTS(
1763     MachineInstr &I) const {
1764   unsigned IntrinsicID = I.getIntrinsicID();
1765   switch (IntrinsicID) {
1766   case Intrinsic::amdgcn_end_cf:
1767     return selectEndCfIntrinsic(I);
1768   case Intrinsic::amdgcn_ds_ordered_add:
1769   case Intrinsic::amdgcn_ds_ordered_swap:
1770     return selectDSOrderedIntrinsic(I, IntrinsicID);
1771   case Intrinsic::amdgcn_ds_gws_init:
1772   case Intrinsic::amdgcn_ds_gws_barrier:
1773   case Intrinsic::amdgcn_ds_gws_sema_v:
1774   case Intrinsic::amdgcn_ds_gws_sema_br:
1775   case Intrinsic::amdgcn_ds_gws_sema_p:
1776   case Intrinsic::amdgcn_ds_gws_sema_release_all:
1777     return selectDSGWSIntrinsic(I, IntrinsicID);
1778   case Intrinsic::amdgcn_ds_append:
1779     return selectDSAppendConsume(I, true);
1780   case Intrinsic::amdgcn_ds_consume:
1781     return selectDSAppendConsume(I, false);
1782   case Intrinsic::amdgcn_s_barrier:
1783     return selectSBarrier(I);
1784   case Intrinsic::amdgcn_global_atomic_fadd:
1785     return selectGlobalAtomicFadd(I, I.getOperand(2), I.getOperand(3));
1786   default: {
1787     return selectImpl(I, *CoverageInfo);
1788   }
1789   }
1790 }
1791 
1792 bool AMDGPUInstructionSelector::selectG_SELECT(MachineInstr &I) const {
1793   if (selectImpl(I, *CoverageInfo))
1794     return true;
1795 
1796   MachineBasicBlock *BB = I.getParent();
1797   const DebugLoc &DL = I.getDebugLoc();
1798 
1799   Register DstReg = I.getOperand(0).getReg();
1800   unsigned Size = RBI.getSizeInBits(DstReg, *MRI, TRI);
1801   assert(Size <= 32 || Size == 64);
1802   const MachineOperand &CCOp = I.getOperand(1);
1803   Register CCReg = CCOp.getReg();
1804   if (!isVCC(CCReg, *MRI)) {
1805     unsigned SelectOpcode = Size == 64 ? AMDGPU::S_CSELECT_B64 :
1806                                          AMDGPU::S_CSELECT_B32;
1807     MachineInstr *CopySCC = BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), AMDGPU::SCC)
1808             .addReg(CCReg);
1809 
1810     // The generic constrainSelectedInstRegOperands doesn't work for the scc register
1811     // bank, because it does not cover the register class that we used to represent
1812     // for it.  So we need to manually set the register class here.
1813     if (!MRI->getRegClassOrNull(CCReg))
1814         MRI->setRegClass(CCReg, TRI.getConstrainedRegClassForOperand(CCOp, *MRI));
1815     MachineInstr *Select = BuildMI(*BB, &I, DL, TII.get(SelectOpcode), DstReg)
1816             .add(I.getOperand(2))
1817             .add(I.getOperand(3));
1818 
1819     bool Ret = false;
1820     Ret |= constrainSelectedInstRegOperands(*Select, TII, TRI, RBI);
1821     Ret |= constrainSelectedInstRegOperands(*CopySCC, TII, TRI, RBI);
1822     I.eraseFromParent();
1823     return Ret;
1824   }
1825 
1826   // Wide VGPR select should have been split in RegBankSelect.
1827   if (Size > 32)
1828     return false;
1829 
1830   MachineInstr *Select =
1831       BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_CNDMASK_B32_e64), DstReg)
1832               .addImm(0)
1833               .add(I.getOperand(3))
1834               .addImm(0)
1835               .add(I.getOperand(2))
1836               .add(I.getOperand(1));
1837 
1838   bool Ret = constrainSelectedInstRegOperands(*Select, TII, TRI, RBI);
1839   I.eraseFromParent();
1840   return Ret;
1841 }
1842 
1843 static int sizeToSubRegIndex(unsigned Size) {
1844   switch (Size) {
1845   case 32:
1846     return AMDGPU::sub0;
1847   case 64:
1848     return AMDGPU::sub0_sub1;
1849   case 96:
1850     return AMDGPU::sub0_sub1_sub2;
1851   case 128:
1852     return AMDGPU::sub0_sub1_sub2_sub3;
1853   case 256:
1854     return AMDGPU::sub0_sub1_sub2_sub3_sub4_sub5_sub6_sub7;
1855   default:
1856     if (Size < 32)
1857       return AMDGPU::sub0;
1858     if (Size > 256)
1859       return -1;
1860     return sizeToSubRegIndex(PowerOf2Ceil(Size));
1861   }
1862 }
1863 
1864 bool AMDGPUInstructionSelector::selectG_TRUNC(MachineInstr &I) const {
1865   Register DstReg = I.getOperand(0).getReg();
1866   Register SrcReg = I.getOperand(1).getReg();
1867   const LLT DstTy = MRI->getType(DstReg);
1868   const LLT SrcTy = MRI->getType(SrcReg);
1869   const LLT S1 = LLT::scalar(1);
1870 
1871   const RegisterBank *SrcRB = RBI.getRegBank(SrcReg, *MRI, TRI);
1872   const RegisterBank *DstRB;
1873   if (DstTy == S1) {
1874     // This is a special case. We don't treat s1 for legalization artifacts as
1875     // vcc booleans.
1876     DstRB = SrcRB;
1877   } else {
1878     DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
1879     if (SrcRB != DstRB)
1880       return false;
1881   }
1882 
1883   const bool IsVALU = DstRB->getID() == AMDGPU::VGPRRegBankID;
1884 
1885   unsigned DstSize = DstTy.getSizeInBits();
1886   unsigned SrcSize = SrcTy.getSizeInBits();
1887 
1888   const TargetRegisterClass *SrcRC
1889     = TRI.getRegClassForSizeOnBank(SrcSize, *SrcRB, *MRI);
1890   const TargetRegisterClass *DstRC
1891     = TRI.getRegClassForSizeOnBank(DstSize, *DstRB, *MRI);
1892   if (!SrcRC || !DstRC)
1893     return false;
1894 
1895   if (!RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI) ||
1896       !RBI.constrainGenericRegister(DstReg, *DstRC, *MRI)) {
1897     LLVM_DEBUG(dbgs() << "Failed to constrain G_TRUNC\n");
1898     return false;
1899   }
1900 
1901   if (DstTy == LLT::fixed_vector(2, 16) && SrcTy == LLT::fixed_vector(2, 32)) {
1902     MachineBasicBlock *MBB = I.getParent();
1903     const DebugLoc &DL = I.getDebugLoc();
1904 
1905     Register LoReg = MRI->createVirtualRegister(DstRC);
1906     Register HiReg = MRI->createVirtualRegister(DstRC);
1907     BuildMI(*MBB, I, DL, TII.get(AMDGPU::COPY), LoReg)
1908       .addReg(SrcReg, 0, AMDGPU::sub0);
1909     BuildMI(*MBB, I, DL, TII.get(AMDGPU::COPY), HiReg)
1910       .addReg(SrcReg, 0, AMDGPU::sub1);
1911 
1912     if (IsVALU && STI.hasSDWA()) {
1913       // Write the low 16-bits of the high element into the high 16-bits of the
1914       // low element.
1915       MachineInstr *MovSDWA =
1916         BuildMI(*MBB, I, DL, TII.get(AMDGPU::V_MOV_B32_sdwa), DstReg)
1917         .addImm(0)                             // $src0_modifiers
1918         .addReg(HiReg)                         // $src0
1919         .addImm(0)                             // $clamp
1920         .addImm(AMDGPU::SDWA::WORD_1)          // $dst_sel
1921         .addImm(AMDGPU::SDWA::UNUSED_PRESERVE) // $dst_unused
1922         .addImm(AMDGPU::SDWA::WORD_0)          // $src0_sel
1923         .addReg(LoReg, RegState::Implicit);
1924       MovSDWA->tieOperands(0, MovSDWA->getNumOperands() - 1);
1925     } else {
1926       Register TmpReg0 = MRI->createVirtualRegister(DstRC);
1927       Register TmpReg1 = MRI->createVirtualRegister(DstRC);
1928       Register ImmReg = MRI->createVirtualRegister(DstRC);
1929       if (IsVALU) {
1930         BuildMI(*MBB, I, DL, TII.get(AMDGPU::V_LSHLREV_B32_e64), TmpReg0)
1931           .addImm(16)
1932           .addReg(HiReg);
1933       } else {
1934         BuildMI(*MBB, I, DL, TII.get(AMDGPU::S_LSHL_B32), TmpReg0)
1935           .addReg(HiReg)
1936           .addImm(16);
1937       }
1938 
1939       unsigned MovOpc = IsVALU ? AMDGPU::V_MOV_B32_e32 : AMDGPU::S_MOV_B32;
1940       unsigned AndOpc = IsVALU ? AMDGPU::V_AND_B32_e64 : AMDGPU::S_AND_B32;
1941       unsigned OrOpc = IsVALU ? AMDGPU::V_OR_B32_e64 : AMDGPU::S_OR_B32;
1942 
1943       BuildMI(*MBB, I, DL, TII.get(MovOpc), ImmReg)
1944         .addImm(0xffff);
1945       BuildMI(*MBB, I, DL, TII.get(AndOpc), TmpReg1)
1946         .addReg(LoReg)
1947         .addReg(ImmReg);
1948       BuildMI(*MBB, I, DL, TII.get(OrOpc), DstReg)
1949         .addReg(TmpReg0)
1950         .addReg(TmpReg1);
1951     }
1952 
1953     I.eraseFromParent();
1954     return true;
1955   }
1956 
1957   if (!DstTy.isScalar())
1958     return false;
1959 
1960   if (SrcSize > 32) {
1961     int SubRegIdx = sizeToSubRegIndex(DstSize);
1962     if (SubRegIdx == -1)
1963       return false;
1964 
1965     // Deal with weird cases where the class only partially supports the subreg
1966     // index.
1967     const TargetRegisterClass *SrcWithSubRC
1968       = TRI.getSubClassWithSubReg(SrcRC, SubRegIdx);
1969     if (!SrcWithSubRC)
1970       return false;
1971 
1972     if (SrcWithSubRC != SrcRC) {
1973       if (!RBI.constrainGenericRegister(SrcReg, *SrcWithSubRC, *MRI))
1974         return false;
1975     }
1976 
1977     I.getOperand(1).setSubReg(SubRegIdx);
1978   }
1979 
1980   I.setDesc(TII.get(TargetOpcode::COPY));
1981   return true;
1982 }
1983 
1984 /// \returns true if a bitmask for \p Size bits will be an inline immediate.
1985 static bool shouldUseAndMask(unsigned Size, unsigned &Mask) {
1986   Mask = maskTrailingOnes<unsigned>(Size);
1987   int SignedMask = static_cast<int>(Mask);
1988   return SignedMask >= -16 && SignedMask <= 64;
1989 }
1990 
1991 // Like RegisterBankInfo::getRegBank, but don't assume vcc for s1.
1992 const RegisterBank *AMDGPUInstructionSelector::getArtifactRegBank(
1993   Register Reg, const MachineRegisterInfo &MRI,
1994   const TargetRegisterInfo &TRI) const {
1995   const RegClassOrRegBank &RegClassOrBank = MRI.getRegClassOrRegBank(Reg);
1996   if (auto *RB = RegClassOrBank.dyn_cast<const RegisterBank *>())
1997     return RB;
1998 
1999   // Ignore the type, since we don't use vcc in artifacts.
2000   if (auto *RC = RegClassOrBank.dyn_cast<const TargetRegisterClass *>())
2001     return &RBI.getRegBankFromRegClass(*RC, LLT());
2002   return nullptr;
2003 }
2004 
2005 bool AMDGPUInstructionSelector::selectG_SZA_EXT(MachineInstr &I) const {
2006   bool InReg = I.getOpcode() == AMDGPU::G_SEXT_INREG;
2007   bool Signed = I.getOpcode() == AMDGPU::G_SEXT || InReg;
2008   const DebugLoc &DL = I.getDebugLoc();
2009   MachineBasicBlock &MBB = *I.getParent();
2010   const Register DstReg = I.getOperand(0).getReg();
2011   const Register SrcReg = I.getOperand(1).getReg();
2012 
2013   const LLT DstTy = MRI->getType(DstReg);
2014   const LLT SrcTy = MRI->getType(SrcReg);
2015   const unsigned SrcSize = I.getOpcode() == AMDGPU::G_SEXT_INREG ?
2016     I.getOperand(2).getImm() : SrcTy.getSizeInBits();
2017   const unsigned DstSize = DstTy.getSizeInBits();
2018   if (!DstTy.isScalar())
2019     return false;
2020 
2021   // Artifact casts should never use vcc.
2022   const RegisterBank *SrcBank = getArtifactRegBank(SrcReg, *MRI, TRI);
2023 
2024   // FIXME: This should probably be illegal and split earlier.
2025   if (I.getOpcode() == AMDGPU::G_ANYEXT) {
2026     if (DstSize <= 32)
2027       return selectCOPY(I);
2028 
2029     const TargetRegisterClass *SrcRC =
2030         TRI.getRegClassForTypeOnBank(SrcTy, *SrcBank, *MRI);
2031     const RegisterBank *DstBank = RBI.getRegBank(DstReg, *MRI, TRI);
2032     const TargetRegisterClass *DstRC =
2033         TRI.getRegClassForSizeOnBank(DstSize, *DstBank, *MRI);
2034 
2035     Register UndefReg = MRI->createVirtualRegister(SrcRC);
2036     BuildMI(MBB, I, DL, TII.get(AMDGPU::IMPLICIT_DEF), UndefReg);
2037     BuildMI(MBB, I, DL, TII.get(AMDGPU::REG_SEQUENCE), DstReg)
2038       .addReg(SrcReg)
2039       .addImm(AMDGPU::sub0)
2040       .addReg(UndefReg)
2041       .addImm(AMDGPU::sub1);
2042     I.eraseFromParent();
2043 
2044     return RBI.constrainGenericRegister(DstReg, *DstRC, *MRI) &&
2045            RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI);
2046   }
2047 
2048   if (SrcBank->getID() == AMDGPU::VGPRRegBankID && DstSize <= 32) {
2049     // 64-bit should have been split up in RegBankSelect
2050 
2051     // Try to use an and with a mask if it will save code size.
2052     unsigned Mask;
2053     if (!Signed && shouldUseAndMask(SrcSize, Mask)) {
2054       MachineInstr *ExtI =
2055       BuildMI(MBB, I, DL, TII.get(AMDGPU::V_AND_B32_e32), DstReg)
2056         .addImm(Mask)
2057         .addReg(SrcReg);
2058       I.eraseFromParent();
2059       return constrainSelectedInstRegOperands(*ExtI, TII, TRI, RBI);
2060     }
2061 
2062     const unsigned BFE = Signed ? AMDGPU::V_BFE_I32_e64 : AMDGPU::V_BFE_U32_e64;
2063     MachineInstr *ExtI =
2064       BuildMI(MBB, I, DL, TII.get(BFE), DstReg)
2065       .addReg(SrcReg)
2066       .addImm(0) // Offset
2067       .addImm(SrcSize); // Width
2068     I.eraseFromParent();
2069     return constrainSelectedInstRegOperands(*ExtI, TII, TRI, RBI);
2070   }
2071 
2072   if (SrcBank->getID() == AMDGPU::SGPRRegBankID && DstSize <= 64) {
2073     const TargetRegisterClass &SrcRC = InReg && DstSize > 32 ?
2074       AMDGPU::SReg_64RegClass : AMDGPU::SReg_32RegClass;
2075     if (!RBI.constrainGenericRegister(SrcReg, SrcRC, *MRI))
2076       return false;
2077 
2078     if (Signed && DstSize == 32 && (SrcSize == 8 || SrcSize == 16)) {
2079       const unsigned SextOpc = SrcSize == 8 ?
2080         AMDGPU::S_SEXT_I32_I8 : AMDGPU::S_SEXT_I32_I16;
2081       BuildMI(MBB, I, DL, TII.get(SextOpc), DstReg)
2082         .addReg(SrcReg);
2083       I.eraseFromParent();
2084       return RBI.constrainGenericRegister(DstReg, AMDGPU::SReg_32RegClass, *MRI);
2085     }
2086 
2087     const unsigned BFE64 = Signed ? AMDGPU::S_BFE_I64 : AMDGPU::S_BFE_U64;
2088     const unsigned BFE32 = Signed ? AMDGPU::S_BFE_I32 : AMDGPU::S_BFE_U32;
2089 
2090     // Scalar BFE is encoded as S1[5:0] = offset, S1[22:16]= width.
2091     if (DstSize > 32 && (SrcSize <= 32 || InReg)) {
2092       // We need a 64-bit register source, but the high bits don't matter.
2093       Register ExtReg = MRI->createVirtualRegister(&AMDGPU::SReg_64RegClass);
2094       Register UndefReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2095       unsigned SubReg = InReg ? AMDGPU::sub0 : 0;
2096 
2097       BuildMI(MBB, I, DL, TII.get(AMDGPU::IMPLICIT_DEF), UndefReg);
2098       BuildMI(MBB, I, DL, TII.get(AMDGPU::REG_SEQUENCE), ExtReg)
2099         .addReg(SrcReg, 0, SubReg)
2100         .addImm(AMDGPU::sub0)
2101         .addReg(UndefReg)
2102         .addImm(AMDGPU::sub1);
2103 
2104       BuildMI(MBB, I, DL, TII.get(BFE64), DstReg)
2105         .addReg(ExtReg)
2106         .addImm(SrcSize << 16);
2107 
2108       I.eraseFromParent();
2109       return RBI.constrainGenericRegister(DstReg, AMDGPU::SReg_64RegClass, *MRI);
2110     }
2111 
2112     unsigned Mask;
2113     if (!Signed && shouldUseAndMask(SrcSize, Mask)) {
2114       BuildMI(MBB, I, DL, TII.get(AMDGPU::S_AND_B32), DstReg)
2115         .addReg(SrcReg)
2116         .addImm(Mask);
2117     } else {
2118       BuildMI(MBB, I, DL, TII.get(BFE32), DstReg)
2119         .addReg(SrcReg)
2120         .addImm(SrcSize << 16);
2121     }
2122 
2123     I.eraseFromParent();
2124     return RBI.constrainGenericRegister(DstReg, AMDGPU::SReg_32RegClass, *MRI);
2125   }
2126 
2127   return false;
2128 }
2129 
2130 bool AMDGPUInstructionSelector::selectG_CONSTANT(MachineInstr &I) const {
2131   MachineBasicBlock *BB = I.getParent();
2132   MachineOperand &ImmOp = I.getOperand(1);
2133   Register DstReg = I.getOperand(0).getReg();
2134   unsigned Size = MRI->getType(DstReg).getSizeInBits();
2135 
2136   // The AMDGPU backend only supports Imm operands and not CImm or FPImm.
2137   if (ImmOp.isFPImm()) {
2138     const APInt &Imm = ImmOp.getFPImm()->getValueAPF().bitcastToAPInt();
2139     ImmOp.ChangeToImmediate(Imm.getZExtValue());
2140   } else if (ImmOp.isCImm()) {
2141     ImmOp.ChangeToImmediate(ImmOp.getCImm()->getSExtValue());
2142   } else {
2143     llvm_unreachable("Not supported by g_constants");
2144   }
2145 
2146   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
2147   const bool IsSgpr = DstRB->getID() == AMDGPU::SGPRRegBankID;
2148 
2149   unsigned Opcode;
2150   if (DstRB->getID() == AMDGPU::VCCRegBankID) {
2151     Opcode = STI.isWave32() ? AMDGPU::S_MOV_B32 : AMDGPU::S_MOV_B64;
2152   } else {
2153     Opcode = IsSgpr ? AMDGPU::S_MOV_B32 : AMDGPU::V_MOV_B32_e32;
2154 
2155     // We should never produce s1 values on banks other than VCC. If the user of
2156     // this already constrained the register, we may incorrectly think it's VCC
2157     // if it wasn't originally.
2158     if (Size == 1)
2159       return false;
2160   }
2161 
2162   if (Size != 64) {
2163     I.setDesc(TII.get(Opcode));
2164     I.addImplicitDefUseOperands(*MF);
2165     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
2166   }
2167 
2168   const DebugLoc &DL = I.getDebugLoc();
2169 
2170   APInt Imm(Size, I.getOperand(1).getImm());
2171 
2172   MachineInstr *ResInst;
2173   if (IsSgpr && TII.isInlineConstant(Imm)) {
2174     ResInst = BuildMI(*BB, &I, DL, TII.get(AMDGPU::S_MOV_B64), DstReg)
2175       .addImm(I.getOperand(1).getImm());
2176   } else {
2177     const TargetRegisterClass *RC = IsSgpr ?
2178       &AMDGPU::SReg_32RegClass : &AMDGPU::VGPR_32RegClass;
2179     Register LoReg = MRI->createVirtualRegister(RC);
2180     Register HiReg = MRI->createVirtualRegister(RC);
2181 
2182     BuildMI(*BB, &I, DL, TII.get(Opcode), LoReg)
2183       .addImm(Imm.trunc(32).getZExtValue());
2184 
2185     BuildMI(*BB, &I, DL, TII.get(Opcode), HiReg)
2186       .addImm(Imm.ashr(32).getZExtValue());
2187 
2188     ResInst = BuildMI(*BB, &I, DL, TII.get(AMDGPU::REG_SEQUENCE), DstReg)
2189       .addReg(LoReg)
2190       .addImm(AMDGPU::sub0)
2191       .addReg(HiReg)
2192       .addImm(AMDGPU::sub1);
2193   }
2194 
2195   // We can't call constrainSelectedInstRegOperands here, because it doesn't
2196   // work for target independent opcodes
2197   I.eraseFromParent();
2198   const TargetRegisterClass *DstRC =
2199     TRI.getConstrainedRegClassForOperand(ResInst->getOperand(0), *MRI);
2200   if (!DstRC)
2201     return true;
2202   return RBI.constrainGenericRegister(DstReg, *DstRC, *MRI);
2203 }
2204 
2205 bool AMDGPUInstructionSelector::selectG_FNEG(MachineInstr &MI) const {
2206   // Only manually handle the f64 SGPR case.
2207   //
2208   // FIXME: This is a workaround for 2.5 different tablegen problems. Because
2209   // the bit ops theoretically have a second result due to the implicit def of
2210   // SCC, the GlobalISelEmitter is overly conservative and rejects it. Fixing
2211   // that is easy by disabling the check. The result works, but uses a
2212   // nonsensical sreg32orlds_and_sreg_1 regclass.
2213   //
2214   // The DAG emitter is more problematic, and incorrectly adds both S_XOR_B32 to
2215   // the variadic REG_SEQUENCE operands.
2216 
2217   Register Dst = MI.getOperand(0).getReg();
2218   const RegisterBank *DstRB = RBI.getRegBank(Dst, *MRI, TRI);
2219   if (DstRB->getID() != AMDGPU::SGPRRegBankID ||
2220       MRI->getType(Dst) != LLT::scalar(64))
2221     return false;
2222 
2223   Register Src = MI.getOperand(1).getReg();
2224   MachineInstr *Fabs = getOpcodeDef(TargetOpcode::G_FABS, Src, *MRI);
2225   if (Fabs)
2226     Src = Fabs->getOperand(1).getReg();
2227 
2228   if (!RBI.constrainGenericRegister(Src, AMDGPU::SReg_64RegClass, *MRI) ||
2229       !RBI.constrainGenericRegister(Dst, AMDGPU::SReg_64RegClass, *MRI))
2230     return false;
2231 
2232   MachineBasicBlock *BB = MI.getParent();
2233   const DebugLoc &DL = MI.getDebugLoc();
2234   Register LoReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2235   Register HiReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2236   Register ConstReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2237   Register OpReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2238 
2239   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), LoReg)
2240     .addReg(Src, 0, AMDGPU::sub0);
2241   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), HiReg)
2242     .addReg(Src, 0, AMDGPU::sub1);
2243   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::S_MOV_B32), ConstReg)
2244     .addImm(0x80000000);
2245 
2246   // Set or toggle sign bit.
2247   unsigned Opc = Fabs ? AMDGPU::S_OR_B32 : AMDGPU::S_XOR_B32;
2248   BuildMI(*BB, &MI, DL, TII.get(Opc), OpReg)
2249     .addReg(HiReg)
2250     .addReg(ConstReg);
2251   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::REG_SEQUENCE), Dst)
2252     .addReg(LoReg)
2253     .addImm(AMDGPU::sub0)
2254     .addReg(OpReg)
2255     .addImm(AMDGPU::sub1);
2256   MI.eraseFromParent();
2257   return true;
2258 }
2259 
2260 // FIXME: This is a workaround for the same tablegen problems as G_FNEG
2261 bool AMDGPUInstructionSelector::selectG_FABS(MachineInstr &MI) const {
2262   Register Dst = MI.getOperand(0).getReg();
2263   const RegisterBank *DstRB = RBI.getRegBank(Dst, *MRI, TRI);
2264   if (DstRB->getID() != AMDGPU::SGPRRegBankID ||
2265       MRI->getType(Dst) != LLT::scalar(64))
2266     return false;
2267 
2268   Register Src = MI.getOperand(1).getReg();
2269   MachineBasicBlock *BB = MI.getParent();
2270   const DebugLoc &DL = MI.getDebugLoc();
2271   Register LoReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2272   Register HiReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2273   Register ConstReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2274   Register OpReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2275 
2276   if (!RBI.constrainGenericRegister(Src, AMDGPU::SReg_64RegClass, *MRI) ||
2277       !RBI.constrainGenericRegister(Dst, AMDGPU::SReg_64RegClass, *MRI))
2278     return false;
2279 
2280   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), LoReg)
2281     .addReg(Src, 0, AMDGPU::sub0);
2282   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), HiReg)
2283     .addReg(Src, 0, AMDGPU::sub1);
2284   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::S_MOV_B32), ConstReg)
2285     .addImm(0x7fffffff);
2286 
2287   // Clear sign bit.
2288   // TODO: Should this used S_BITSET0_*?
2289   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::S_AND_B32), OpReg)
2290     .addReg(HiReg)
2291     .addReg(ConstReg);
2292   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::REG_SEQUENCE), Dst)
2293     .addReg(LoReg)
2294     .addImm(AMDGPU::sub0)
2295     .addReg(OpReg)
2296     .addImm(AMDGPU::sub1);
2297 
2298   MI.eraseFromParent();
2299   return true;
2300 }
2301 
2302 static bool isConstant(const MachineInstr &MI) {
2303   return MI.getOpcode() == TargetOpcode::G_CONSTANT;
2304 }
2305 
2306 void AMDGPUInstructionSelector::getAddrModeInfo(const MachineInstr &Load,
2307     const MachineRegisterInfo &MRI, SmallVectorImpl<GEPInfo> &AddrInfo) const {
2308 
2309   const MachineInstr *PtrMI = MRI.getUniqueVRegDef(Load.getOperand(1).getReg());
2310 
2311   assert(PtrMI);
2312 
2313   if (PtrMI->getOpcode() != TargetOpcode::G_PTR_ADD)
2314     return;
2315 
2316   GEPInfo GEPInfo(*PtrMI);
2317 
2318   for (unsigned i = 1; i != 3; ++i) {
2319     const MachineOperand &GEPOp = PtrMI->getOperand(i);
2320     const MachineInstr *OpDef = MRI.getUniqueVRegDef(GEPOp.getReg());
2321     assert(OpDef);
2322     if (i == 2 && isConstant(*OpDef)) {
2323       // TODO: Could handle constant base + variable offset, but a combine
2324       // probably should have commuted it.
2325       assert(GEPInfo.Imm == 0);
2326       GEPInfo.Imm = OpDef->getOperand(1).getCImm()->getSExtValue();
2327       continue;
2328     }
2329     const RegisterBank *OpBank = RBI.getRegBank(GEPOp.getReg(), MRI, TRI);
2330     if (OpBank->getID() == AMDGPU::SGPRRegBankID)
2331       GEPInfo.SgprParts.push_back(GEPOp.getReg());
2332     else
2333       GEPInfo.VgprParts.push_back(GEPOp.getReg());
2334   }
2335 
2336   AddrInfo.push_back(GEPInfo);
2337   getAddrModeInfo(*PtrMI, MRI, AddrInfo);
2338 }
2339 
2340 bool AMDGPUInstructionSelector::isSGPR(Register Reg) const {
2341   return RBI.getRegBank(Reg, *MRI, TRI)->getID() == AMDGPU::SGPRRegBankID;
2342 }
2343 
2344 bool AMDGPUInstructionSelector::isInstrUniform(const MachineInstr &MI) const {
2345   if (!MI.hasOneMemOperand())
2346     return false;
2347 
2348   const MachineMemOperand *MMO = *MI.memoperands_begin();
2349   const Value *Ptr = MMO->getValue();
2350 
2351   // UndefValue means this is a load of a kernel input.  These are uniform.
2352   // Sometimes LDS instructions have constant pointers.
2353   // If Ptr is null, then that means this mem operand contains a
2354   // PseudoSourceValue like GOT.
2355   if (!Ptr || isa<UndefValue>(Ptr) || isa<Argument>(Ptr) ||
2356       isa<Constant>(Ptr) || isa<GlobalValue>(Ptr))
2357     return true;
2358 
2359   if (MMO->getAddrSpace() == AMDGPUAS::CONSTANT_ADDRESS_32BIT)
2360     return true;
2361 
2362   const Instruction *I = dyn_cast<Instruction>(Ptr);
2363   return I && I->getMetadata("amdgpu.uniform");
2364 }
2365 
2366 bool AMDGPUInstructionSelector::hasVgprParts(ArrayRef<GEPInfo> AddrInfo) const {
2367   for (const GEPInfo &GEPInfo : AddrInfo) {
2368     if (!GEPInfo.VgprParts.empty())
2369       return true;
2370   }
2371   return false;
2372 }
2373 
2374 void AMDGPUInstructionSelector::initM0(MachineInstr &I) const {
2375   const LLT PtrTy = MRI->getType(I.getOperand(1).getReg());
2376   unsigned AS = PtrTy.getAddressSpace();
2377   if ((AS == AMDGPUAS::LOCAL_ADDRESS || AS == AMDGPUAS::REGION_ADDRESS) &&
2378       STI.ldsRequiresM0Init()) {
2379     MachineBasicBlock *BB = I.getParent();
2380 
2381     // If DS instructions require M0 initialization, insert it before selecting.
2382     BuildMI(*BB, &I, I.getDebugLoc(), TII.get(AMDGPU::S_MOV_B32), AMDGPU::M0)
2383       .addImm(-1);
2384   }
2385 }
2386 
2387 bool AMDGPUInstructionSelector::selectG_LOAD_STORE_ATOMICRMW(
2388   MachineInstr &I) const {
2389   if (I.getOpcode() == TargetOpcode::G_ATOMICRMW_FADD) {
2390     const LLT PtrTy = MRI->getType(I.getOperand(1).getReg());
2391     unsigned AS = PtrTy.getAddressSpace();
2392     if (AS == AMDGPUAS::GLOBAL_ADDRESS)
2393       return selectGlobalAtomicFadd(I, I.getOperand(1), I.getOperand(2));
2394   }
2395 
2396   initM0(I);
2397   return selectImpl(I, *CoverageInfo);
2398 }
2399 
2400 // TODO: No rtn optimization.
2401 bool AMDGPUInstructionSelector::selectG_AMDGPU_ATOMIC_CMPXCHG(
2402   MachineInstr &MI) const {
2403   Register PtrReg = MI.getOperand(1).getReg();
2404   const LLT PtrTy = MRI->getType(PtrReg);
2405   if (PtrTy.getAddressSpace() == AMDGPUAS::FLAT_ADDRESS ||
2406       STI.useFlatForGlobal())
2407     return selectImpl(MI, *CoverageInfo);
2408 
2409   Register DstReg = MI.getOperand(0).getReg();
2410   const LLT Ty = MRI->getType(DstReg);
2411   const bool Is64 = Ty.getSizeInBits() == 64;
2412   const unsigned SubReg = Is64 ? AMDGPU::sub0_sub1 : AMDGPU::sub0;
2413   Register TmpReg = MRI->createVirtualRegister(
2414     Is64 ? &AMDGPU::VReg_128RegClass : &AMDGPU::VReg_64RegClass);
2415 
2416   const DebugLoc &DL = MI.getDebugLoc();
2417   MachineBasicBlock *BB = MI.getParent();
2418 
2419   Register VAddr, RSrcReg, SOffset;
2420   int64_t Offset = 0;
2421 
2422   unsigned Opcode;
2423   if (selectMUBUFOffsetImpl(MI.getOperand(1), RSrcReg, SOffset, Offset)) {
2424     Opcode = Is64 ? AMDGPU::BUFFER_ATOMIC_CMPSWAP_X2_OFFSET_RTN :
2425                              AMDGPU::BUFFER_ATOMIC_CMPSWAP_OFFSET_RTN;
2426   } else if (selectMUBUFAddr64Impl(MI.getOperand(1), VAddr,
2427                                    RSrcReg, SOffset, Offset)) {
2428     Opcode = Is64 ? AMDGPU::BUFFER_ATOMIC_CMPSWAP_X2_ADDR64_RTN :
2429                     AMDGPU::BUFFER_ATOMIC_CMPSWAP_ADDR64_RTN;
2430   } else
2431     return selectImpl(MI, *CoverageInfo);
2432 
2433   auto MIB = BuildMI(*BB, &MI, DL, TII.get(Opcode), TmpReg)
2434     .addReg(MI.getOperand(2).getReg());
2435 
2436   if (VAddr)
2437     MIB.addReg(VAddr);
2438 
2439   MIB.addReg(RSrcReg);
2440   if (SOffset)
2441     MIB.addReg(SOffset);
2442   else
2443     MIB.addImm(0);
2444 
2445   MIB.addImm(Offset);
2446   MIB.addImm(AMDGPU::CPol::GLC);
2447   MIB.cloneMemRefs(MI);
2448 
2449   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), DstReg)
2450     .addReg(TmpReg, RegState::Kill, SubReg);
2451 
2452   MI.eraseFromParent();
2453 
2454   MRI->setRegClass(
2455     DstReg, Is64 ? &AMDGPU::VReg_64RegClass : &AMDGPU::VGPR_32RegClass);
2456   return constrainSelectedInstRegOperands(*MIB, TII, TRI, RBI);
2457 }
2458 
2459 static bool isVCmpResult(Register Reg, MachineRegisterInfo &MRI) {
2460   if (Reg.isPhysical())
2461     return false;
2462 
2463   MachineInstr &MI = *MRI.getUniqueVRegDef(Reg);
2464   const unsigned Opcode = MI.getOpcode();
2465 
2466   if (Opcode == AMDGPU::COPY)
2467     return isVCmpResult(MI.getOperand(1).getReg(), MRI);
2468 
2469   if (Opcode == AMDGPU::G_AND || Opcode == AMDGPU::G_OR ||
2470       Opcode == AMDGPU::G_XOR)
2471     return isVCmpResult(MI.getOperand(1).getReg(), MRI) &&
2472            isVCmpResult(MI.getOperand(2).getReg(), MRI);
2473 
2474   if (Opcode == TargetOpcode::G_INTRINSIC)
2475     return MI.getIntrinsicID() == Intrinsic::amdgcn_class;
2476 
2477   return Opcode == AMDGPU::G_ICMP || Opcode == AMDGPU::G_FCMP;
2478 }
2479 
2480 bool AMDGPUInstructionSelector::selectG_BRCOND(MachineInstr &I) const {
2481   MachineBasicBlock *BB = I.getParent();
2482   MachineOperand &CondOp = I.getOperand(0);
2483   Register CondReg = CondOp.getReg();
2484   const DebugLoc &DL = I.getDebugLoc();
2485 
2486   unsigned BrOpcode;
2487   Register CondPhysReg;
2488   const TargetRegisterClass *ConstrainRC;
2489 
2490   // In SelectionDAG, we inspect the IR block for uniformity metadata to decide
2491   // whether the branch is uniform when selecting the instruction. In
2492   // GlobalISel, we should push that decision into RegBankSelect. Assume for now
2493   // RegBankSelect knows what it's doing if the branch condition is scc, even
2494   // though it currently does not.
2495   if (!isVCC(CondReg, *MRI)) {
2496     if (MRI->getType(CondReg) != LLT::scalar(32))
2497       return false;
2498 
2499     CondPhysReg = AMDGPU::SCC;
2500     BrOpcode = AMDGPU::S_CBRANCH_SCC1;
2501     ConstrainRC = &AMDGPU::SReg_32RegClass;
2502   } else {
2503     // FIXME: Should scc->vcc copies and with exec?
2504 
2505     // Unless the value of CondReg is a result of a V_CMP* instruction then we
2506     // need to insert an and with exec.
2507     if (!isVCmpResult(CondReg, *MRI)) {
2508       const bool Is64 = STI.isWave64();
2509       const unsigned Opcode = Is64 ? AMDGPU::S_AND_B64 : AMDGPU::S_AND_B32;
2510       const Register Exec = Is64 ? AMDGPU::EXEC : AMDGPU::EXEC_LO;
2511 
2512       Register TmpReg = MRI->createVirtualRegister(TRI.getBoolRC());
2513       BuildMI(*BB, &I, DL, TII.get(Opcode), TmpReg)
2514           .addReg(CondReg)
2515           .addReg(Exec);
2516       CondReg = TmpReg;
2517     }
2518 
2519     CondPhysReg = TRI.getVCC();
2520     BrOpcode = AMDGPU::S_CBRANCH_VCCNZ;
2521     ConstrainRC = TRI.getBoolRC();
2522   }
2523 
2524   if (!MRI->getRegClassOrNull(CondReg))
2525     MRI->setRegClass(CondReg, ConstrainRC);
2526 
2527   BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), CondPhysReg)
2528     .addReg(CondReg);
2529   BuildMI(*BB, &I, DL, TII.get(BrOpcode))
2530     .addMBB(I.getOperand(1).getMBB());
2531 
2532   I.eraseFromParent();
2533   return true;
2534 }
2535 
2536 bool AMDGPUInstructionSelector::selectG_GLOBAL_VALUE(
2537   MachineInstr &I) const {
2538   Register DstReg = I.getOperand(0).getReg();
2539   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
2540   const bool IsVGPR = DstRB->getID() == AMDGPU::VGPRRegBankID;
2541   I.setDesc(TII.get(IsVGPR ? AMDGPU::V_MOV_B32_e32 : AMDGPU::S_MOV_B32));
2542   if (IsVGPR)
2543     I.addOperand(*MF, MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
2544 
2545   return RBI.constrainGenericRegister(
2546     DstReg, IsVGPR ? AMDGPU::VGPR_32RegClass : AMDGPU::SReg_32RegClass, *MRI);
2547 }
2548 
2549 bool AMDGPUInstructionSelector::selectG_PTRMASK(MachineInstr &I) const {
2550   Register DstReg = I.getOperand(0).getReg();
2551   Register SrcReg = I.getOperand(1).getReg();
2552   Register MaskReg = I.getOperand(2).getReg();
2553   LLT Ty = MRI->getType(DstReg);
2554   LLT MaskTy = MRI->getType(MaskReg);
2555 
2556   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
2557   const RegisterBank *SrcRB = RBI.getRegBank(SrcReg, *MRI, TRI);
2558   const RegisterBank *MaskRB = RBI.getRegBank(MaskReg, *MRI, TRI);
2559   const bool IsVGPR = DstRB->getID() == AMDGPU::VGPRRegBankID;
2560   if (DstRB != SrcRB) // Should only happen for hand written MIR.
2561     return false;
2562 
2563   unsigned NewOpc = IsVGPR ? AMDGPU::V_AND_B32_e64 : AMDGPU::S_AND_B32;
2564   const TargetRegisterClass &RegRC
2565     = IsVGPR ? AMDGPU::VGPR_32RegClass : AMDGPU::SReg_32RegClass;
2566 
2567   const TargetRegisterClass *DstRC = TRI.getRegClassForTypeOnBank(Ty, *DstRB,
2568                                                                   *MRI);
2569   const TargetRegisterClass *SrcRC = TRI.getRegClassForTypeOnBank(Ty, *SrcRB,
2570                                                                   *MRI);
2571   const TargetRegisterClass *MaskRC =
2572       TRI.getRegClassForTypeOnBank(MaskTy, *MaskRB, *MRI);
2573 
2574   if (!RBI.constrainGenericRegister(DstReg, *DstRC, *MRI) ||
2575       !RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI) ||
2576       !RBI.constrainGenericRegister(MaskReg, *MaskRC, *MRI))
2577     return false;
2578 
2579   MachineBasicBlock *BB = I.getParent();
2580   const DebugLoc &DL = I.getDebugLoc();
2581   if (Ty.getSizeInBits() == 32) {
2582     assert(MaskTy.getSizeInBits() == 32 &&
2583            "ptrmask should have been narrowed during legalize");
2584 
2585     BuildMI(*BB, &I, DL, TII.get(NewOpc), DstReg)
2586       .addReg(SrcReg)
2587       .addReg(MaskReg);
2588     I.eraseFromParent();
2589     return true;
2590   }
2591 
2592   Register HiReg = MRI->createVirtualRegister(&RegRC);
2593   Register LoReg = MRI->createVirtualRegister(&RegRC);
2594 
2595   // Extract the subregisters from the source pointer.
2596   BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), LoReg)
2597     .addReg(SrcReg, 0, AMDGPU::sub0);
2598   BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), HiReg)
2599     .addReg(SrcReg, 0, AMDGPU::sub1);
2600 
2601   Register MaskedLo, MaskedHi;
2602 
2603   // Try to avoid emitting a bit operation when we only need to touch half of
2604   // the 64-bit pointer.
2605   APInt MaskOnes = KnownBits->getKnownOnes(MaskReg).zextOrSelf(64);
2606 
2607   const APInt MaskHi32 = APInt::getHighBitsSet(64, 32);
2608   const APInt MaskLo32 = APInt::getLowBitsSet(64, 32);
2609   if ((MaskOnes & MaskLo32) == MaskLo32) {
2610     // If all the bits in the low half are 1, we only need a copy for it.
2611     MaskedLo = LoReg;
2612   } else {
2613     // Extract the mask subregister and apply the and.
2614     Register MaskLo = MRI->createVirtualRegister(&RegRC);
2615     MaskedLo = MRI->createVirtualRegister(&RegRC);
2616 
2617     BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), MaskLo)
2618       .addReg(MaskReg, 0, AMDGPU::sub0);
2619     BuildMI(*BB, &I, DL, TII.get(NewOpc), MaskedLo)
2620       .addReg(LoReg)
2621       .addReg(MaskLo);
2622   }
2623 
2624   if ((MaskOnes & MaskHi32) == MaskHi32) {
2625     // If all the bits in the high half are 1, we only need a copy for it.
2626     MaskedHi = HiReg;
2627   } else {
2628     Register MaskHi = MRI->createVirtualRegister(&RegRC);
2629     MaskedHi = MRI->createVirtualRegister(&RegRC);
2630 
2631     BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), MaskHi)
2632       .addReg(MaskReg, 0, AMDGPU::sub1);
2633     BuildMI(*BB, &I, DL, TII.get(NewOpc), MaskedHi)
2634       .addReg(HiReg)
2635       .addReg(MaskHi);
2636   }
2637 
2638   BuildMI(*BB, &I, DL, TII.get(AMDGPU::REG_SEQUENCE), DstReg)
2639     .addReg(MaskedLo)
2640     .addImm(AMDGPU::sub0)
2641     .addReg(MaskedHi)
2642     .addImm(AMDGPU::sub1);
2643   I.eraseFromParent();
2644   return true;
2645 }
2646 
2647 /// Return the register to use for the index value, and the subregister to use
2648 /// for the indirectly accessed register.
2649 static std::pair<Register, unsigned>
2650 computeIndirectRegIndex(MachineRegisterInfo &MRI,
2651                         const SIRegisterInfo &TRI,
2652                         const TargetRegisterClass *SuperRC,
2653                         Register IdxReg,
2654                         unsigned EltSize) {
2655   Register IdxBaseReg;
2656   int Offset;
2657 
2658   std::tie(IdxBaseReg, Offset) = AMDGPU::getBaseWithConstantOffset(MRI, IdxReg);
2659   if (IdxBaseReg == AMDGPU::NoRegister) {
2660     // This will happen if the index is a known constant. This should ordinarily
2661     // be legalized out, but handle it as a register just in case.
2662     assert(Offset == 0);
2663     IdxBaseReg = IdxReg;
2664   }
2665 
2666   ArrayRef<int16_t> SubRegs = TRI.getRegSplitParts(SuperRC, EltSize);
2667 
2668   // Skip out of bounds offsets, or else we would end up using an undefined
2669   // register.
2670   if (static_cast<unsigned>(Offset) >= SubRegs.size())
2671     return std::make_pair(IdxReg, SubRegs[0]);
2672   return std::make_pair(IdxBaseReg, SubRegs[Offset]);
2673 }
2674 
2675 bool AMDGPUInstructionSelector::selectG_EXTRACT_VECTOR_ELT(
2676   MachineInstr &MI) const {
2677   Register DstReg = MI.getOperand(0).getReg();
2678   Register SrcReg = MI.getOperand(1).getReg();
2679   Register IdxReg = MI.getOperand(2).getReg();
2680 
2681   LLT DstTy = MRI->getType(DstReg);
2682   LLT SrcTy = MRI->getType(SrcReg);
2683 
2684   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
2685   const RegisterBank *SrcRB = RBI.getRegBank(SrcReg, *MRI, TRI);
2686   const RegisterBank *IdxRB = RBI.getRegBank(IdxReg, *MRI, TRI);
2687 
2688   // The index must be scalar. If it wasn't RegBankSelect should have moved this
2689   // into a waterfall loop.
2690   if (IdxRB->getID() != AMDGPU::SGPRRegBankID)
2691     return false;
2692 
2693   const TargetRegisterClass *SrcRC = TRI.getRegClassForTypeOnBank(SrcTy, *SrcRB,
2694                                                                   *MRI);
2695   const TargetRegisterClass *DstRC = TRI.getRegClassForTypeOnBank(DstTy, *DstRB,
2696                                                                   *MRI);
2697   if (!SrcRC || !DstRC)
2698     return false;
2699   if (!RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI) ||
2700       !RBI.constrainGenericRegister(DstReg, *DstRC, *MRI) ||
2701       !RBI.constrainGenericRegister(IdxReg, AMDGPU::SReg_32RegClass, *MRI))
2702     return false;
2703 
2704   MachineBasicBlock *BB = MI.getParent();
2705   const DebugLoc &DL = MI.getDebugLoc();
2706   const bool Is64 = DstTy.getSizeInBits() == 64;
2707 
2708   unsigned SubReg;
2709   std::tie(IdxReg, SubReg) = computeIndirectRegIndex(*MRI, TRI, SrcRC, IdxReg,
2710                                                      DstTy.getSizeInBits() / 8);
2711 
2712   if (SrcRB->getID() == AMDGPU::SGPRRegBankID) {
2713     if (DstTy.getSizeInBits() != 32 && !Is64)
2714       return false;
2715 
2716     BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
2717       .addReg(IdxReg);
2718 
2719     unsigned Opc = Is64 ? AMDGPU::S_MOVRELS_B64 : AMDGPU::S_MOVRELS_B32;
2720     BuildMI(*BB, &MI, DL, TII.get(Opc), DstReg)
2721       .addReg(SrcReg, 0, SubReg)
2722       .addReg(SrcReg, RegState::Implicit);
2723     MI.eraseFromParent();
2724     return true;
2725   }
2726 
2727   if (SrcRB->getID() != AMDGPU::VGPRRegBankID || DstTy.getSizeInBits() != 32)
2728     return false;
2729 
2730   if (!STI.useVGPRIndexMode()) {
2731     BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
2732       .addReg(IdxReg);
2733     BuildMI(*BB, &MI, DL, TII.get(AMDGPU::V_MOVRELS_B32_e32), DstReg)
2734       .addReg(SrcReg, 0, SubReg)
2735       .addReg(SrcReg, RegState::Implicit);
2736     MI.eraseFromParent();
2737     return true;
2738   }
2739 
2740   const MCInstrDesc &GPRIDXDesc =
2741       TII.getIndirectGPRIDXPseudo(TRI.getRegSizeInBits(*SrcRC), true);
2742   BuildMI(*BB, MI, DL, GPRIDXDesc, DstReg)
2743       .addReg(SrcReg)
2744       .addReg(IdxReg)
2745       .addImm(SubReg);
2746 
2747   MI.eraseFromParent();
2748   return true;
2749 }
2750 
2751 // TODO: Fold insert_vector_elt (extract_vector_elt) into movrelsd
2752 bool AMDGPUInstructionSelector::selectG_INSERT_VECTOR_ELT(
2753   MachineInstr &MI) const {
2754   Register DstReg = MI.getOperand(0).getReg();
2755   Register VecReg = MI.getOperand(1).getReg();
2756   Register ValReg = MI.getOperand(2).getReg();
2757   Register IdxReg = MI.getOperand(3).getReg();
2758 
2759   LLT VecTy = MRI->getType(DstReg);
2760   LLT ValTy = MRI->getType(ValReg);
2761   unsigned VecSize = VecTy.getSizeInBits();
2762   unsigned ValSize = ValTy.getSizeInBits();
2763 
2764   const RegisterBank *VecRB = RBI.getRegBank(VecReg, *MRI, TRI);
2765   const RegisterBank *ValRB = RBI.getRegBank(ValReg, *MRI, TRI);
2766   const RegisterBank *IdxRB = RBI.getRegBank(IdxReg, *MRI, TRI);
2767 
2768   assert(VecTy.getElementType() == ValTy);
2769 
2770   // The index must be scalar. If it wasn't RegBankSelect should have moved this
2771   // into a waterfall loop.
2772   if (IdxRB->getID() != AMDGPU::SGPRRegBankID)
2773     return false;
2774 
2775   const TargetRegisterClass *VecRC = TRI.getRegClassForTypeOnBank(VecTy, *VecRB,
2776                                                                   *MRI);
2777   const TargetRegisterClass *ValRC = TRI.getRegClassForTypeOnBank(ValTy, *ValRB,
2778                                                                   *MRI);
2779 
2780   if (!RBI.constrainGenericRegister(VecReg, *VecRC, *MRI) ||
2781       !RBI.constrainGenericRegister(DstReg, *VecRC, *MRI) ||
2782       !RBI.constrainGenericRegister(ValReg, *ValRC, *MRI) ||
2783       !RBI.constrainGenericRegister(IdxReg, AMDGPU::SReg_32RegClass, *MRI))
2784     return false;
2785 
2786   if (VecRB->getID() == AMDGPU::VGPRRegBankID && ValSize != 32)
2787     return false;
2788 
2789   unsigned SubReg;
2790   std::tie(IdxReg, SubReg) = computeIndirectRegIndex(*MRI, TRI, VecRC, IdxReg,
2791                                                      ValSize / 8);
2792 
2793   const bool IndexMode = VecRB->getID() == AMDGPU::VGPRRegBankID &&
2794                          STI.useVGPRIndexMode();
2795 
2796   MachineBasicBlock *BB = MI.getParent();
2797   const DebugLoc &DL = MI.getDebugLoc();
2798 
2799   if (!IndexMode) {
2800     BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
2801       .addReg(IdxReg);
2802 
2803     const MCInstrDesc &RegWriteOp = TII.getIndirectRegWriteMovRelPseudo(
2804         VecSize, ValSize, VecRB->getID() == AMDGPU::SGPRRegBankID);
2805     BuildMI(*BB, MI, DL, RegWriteOp, DstReg)
2806         .addReg(VecReg)
2807         .addReg(ValReg)
2808         .addImm(SubReg);
2809     MI.eraseFromParent();
2810     return true;
2811   }
2812 
2813   const MCInstrDesc &GPRIDXDesc =
2814       TII.getIndirectGPRIDXPseudo(TRI.getRegSizeInBits(*VecRC), false);
2815   BuildMI(*BB, MI, DL, GPRIDXDesc, DstReg)
2816       .addReg(VecReg)
2817       .addReg(ValReg)
2818       .addReg(IdxReg)
2819       .addImm(SubReg);
2820 
2821   MI.eraseFromParent();
2822   return true;
2823 }
2824 
2825 static bool isZeroOrUndef(int X) {
2826   return X == 0 || X == -1;
2827 }
2828 
2829 static bool isOneOrUndef(int X) {
2830   return X == 1 || X == -1;
2831 }
2832 
2833 static bool isZeroOrOneOrUndef(int X) {
2834   return X == 0 || X == 1 || X == -1;
2835 }
2836 
2837 // Normalize a VOP3P shuffle mask to refer to the low/high half of a single
2838 // 32-bit register.
2839 static Register normalizeVOP3PMask(int NewMask[2], Register Src0, Register Src1,
2840                                    ArrayRef<int> Mask) {
2841   NewMask[0] = Mask[0];
2842   NewMask[1] = Mask[1];
2843   if (isZeroOrOneOrUndef(Mask[0]) && isZeroOrOneOrUndef(Mask[1]))
2844     return Src0;
2845 
2846   assert(NewMask[0] == 2 || NewMask[0] == 3 || NewMask[0] == -1);
2847   assert(NewMask[1] == 2 || NewMask[1] == 3 || NewMask[1] == -1);
2848 
2849   // Shift the mask inputs to be 0/1;
2850   NewMask[0] = NewMask[0] == -1 ? -1 : NewMask[0] - 2;
2851   NewMask[1] = NewMask[1] == -1 ? -1 : NewMask[1] - 2;
2852   return Src1;
2853 }
2854 
2855 // This is only legal with VOP3P instructions as an aid to op_sel matching.
2856 bool AMDGPUInstructionSelector::selectG_SHUFFLE_VECTOR(
2857   MachineInstr &MI) const {
2858   Register DstReg = MI.getOperand(0).getReg();
2859   Register Src0Reg = MI.getOperand(1).getReg();
2860   Register Src1Reg = MI.getOperand(2).getReg();
2861   ArrayRef<int> ShufMask = MI.getOperand(3).getShuffleMask();
2862 
2863   const LLT V2S16 = LLT::fixed_vector(2, 16);
2864   if (MRI->getType(DstReg) != V2S16 || MRI->getType(Src0Reg) != V2S16)
2865     return false;
2866 
2867   if (!AMDGPU::isLegalVOP3PShuffleMask(ShufMask))
2868     return false;
2869 
2870   assert(ShufMask.size() == 2);
2871   assert(STI.hasSDWA() && "no target has VOP3P but not SDWA");
2872 
2873   MachineBasicBlock *MBB = MI.getParent();
2874   const DebugLoc &DL = MI.getDebugLoc();
2875 
2876   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
2877   const bool IsVALU = DstRB->getID() == AMDGPU::VGPRRegBankID;
2878   const TargetRegisterClass &RC = IsVALU ?
2879     AMDGPU::VGPR_32RegClass : AMDGPU::SReg_32RegClass;
2880 
2881   // Handle the degenerate case which should have folded out.
2882   if (ShufMask[0] == -1 && ShufMask[1] == -1) {
2883     BuildMI(*MBB, MI, DL, TII.get(AMDGPU::IMPLICIT_DEF), DstReg);
2884 
2885     MI.eraseFromParent();
2886     return RBI.constrainGenericRegister(DstReg, RC, *MRI);
2887   }
2888 
2889   // A legal VOP3P mask only reads one of the sources.
2890   int Mask[2];
2891   Register SrcVec = normalizeVOP3PMask(Mask, Src0Reg, Src1Reg, ShufMask);
2892 
2893   if (!RBI.constrainGenericRegister(DstReg, RC, *MRI) ||
2894       !RBI.constrainGenericRegister(SrcVec, RC, *MRI))
2895     return false;
2896 
2897   // TODO: This also should have been folded out
2898   if (isZeroOrUndef(Mask[0]) && isOneOrUndef(Mask[1])) {
2899     BuildMI(*MBB, MI, DL, TII.get(AMDGPU::COPY), DstReg)
2900       .addReg(SrcVec);
2901 
2902     MI.eraseFromParent();
2903     return true;
2904   }
2905 
2906   if (Mask[0] == 1 && Mask[1] == -1) {
2907     if (IsVALU) {
2908       BuildMI(*MBB, MI, DL, TII.get(AMDGPU::V_LSHRREV_B32_e64), DstReg)
2909         .addImm(16)
2910         .addReg(SrcVec);
2911     } else {
2912       BuildMI(*MBB, MI, DL, TII.get(AMDGPU::S_LSHR_B32), DstReg)
2913         .addReg(SrcVec)
2914         .addImm(16);
2915     }
2916   } else if (Mask[0] == -1 && Mask[1] == 0) {
2917     if (IsVALU) {
2918       BuildMI(*MBB, MI, DL, TII.get(AMDGPU::V_LSHLREV_B32_e64), DstReg)
2919         .addImm(16)
2920         .addReg(SrcVec);
2921     } else {
2922       BuildMI(*MBB, MI, DL, TII.get(AMDGPU::S_LSHL_B32), DstReg)
2923         .addReg(SrcVec)
2924         .addImm(16);
2925     }
2926   } else if (Mask[0] == 0 && Mask[1] == 0) {
2927     if (IsVALU) {
2928       // Write low half of the register into the high half.
2929       MachineInstr *MovSDWA =
2930         BuildMI(*MBB, MI, DL, TII.get(AMDGPU::V_MOV_B32_sdwa), DstReg)
2931         .addImm(0)                             // $src0_modifiers
2932         .addReg(SrcVec)                        // $src0
2933         .addImm(0)                             // $clamp
2934         .addImm(AMDGPU::SDWA::WORD_1)          // $dst_sel
2935         .addImm(AMDGPU::SDWA::UNUSED_PRESERVE) // $dst_unused
2936         .addImm(AMDGPU::SDWA::WORD_0)          // $src0_sel
2937         .addReg(SrcVec, RegState::Implicit);
2938       MovSDWA->tieOperands(0, MovSDWA->getNumOperands() - 1);
2939     } else {
2940       BuildMI(*MBB, MI, DL, TII.get(AMDGPU::S_PACK_LL_B32_B16), DstReg)
2941         .addReg(SrcVec)
2942         .addReg(SrcVec);
2943     }
2944   } else if (Mask[0] == 1 && Mask[1] == 1) {
2945     if (IsVALU) {
2946       // Write high half of the register into the low half.
2947       MachineInstr *MovSDWA =
2948         BuildMI(*MBB, MI, DL, TII.get(AMDGPU::V_MOV_B32_sdwa), DstReg)
2949         .addImm(0)                             // $src0_modifiers
2950         .addReg(SrcVec)                        // $src0
2951         .addImm(0)                             // $clamp
2952         .addImm(AMDGPU::SDWA::WORD_0)          // $dst_sel
2953         .addImm(AMDGPU::SDWA::UNUSED_PRESERVE) // $dst_unused
2954         .addImm(AMDGPU::SDWA::WORD_1)          // $src0_sel
2955         .addReg(SrcVec, RegState::Implicit);
2956       MovSDWA->tieOperands(0, MovSDWA->getNumOperands() - 1);
2957     } else {
2958       BuildMI(*MBB, MI, DL, TII.get(AMDGPU::S_PACK_HH_B32_B16), DstReg)
2959         .addReg(SrcVec)
2960         .addReg(SrcVec);
2961     }
2962   } else if (Mask[0] == 1 && Mask[1] == 0) {
2963     if (IsVALU) {
2964       BuildMI(*MBB, MI, DL, TII.get(AMDGPU::V_ALIGNBIT_B32_e64), DstReg)
2965         .addReg(SrcVec)
2966         .addReg(SrcVec)
2967         .addImm(16);
2968     } else {
2969       Register TmpReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2970       BuildMI(*MBB, MI, DL, TII.get(AMDGPU::S_LSHR_B32), TmpReg)
2971         .addReg(SrcVec)
2972         .addImm(16);
2973       BuildMI(*MBB, MI, DL, TII.get(AMDGPU::S_PACK_LL_B32_B16), DstReg)
2974         .addReg(TmpReg)
2975         .addReg(SrcVec);
2976     }
2977   } else
2978     llvm_unreachable("all shuffle masks should be handled");
2979 
2980   MI.eraseFromParent();
2981   return true;
2982 }
2983 
2984 bool AMDGPUInstructionSelector::selectAMDGPU_BUFFER_ATOMIC_FADD(
2985   MachineInstr &MI) const {
2986   if (STI.hasGFX90AInsts())
2987     return selectImpl(MI, *CoverageInfo);
2988 
2989   MachineBasicBlock *MBB = MI.getParent();
2990   const DebugLoc &DL = MI.getDebugLoc();
2991 
2992   if (!MRI->use_nodbg_empty(MI.getOperand(0).getReg())) {
2993     Function &F = MBB->getParent()->getFunction();
2994     DiagnosticInfoUnsupported
2995       NoFpRet(F, "return versions of fp atomics not supported",
2996               MI.getDebugLoc(), DS_Error);
2997     F.getContext().diagnose(NoFpRet);
2998     return false;
2999   }
3000 
3001   // FIXME: This is only needed because tablegen requires number of dst operands
3002   // in match and replace pattern to be the same. Otherwise patterns can be
3003   // exported from SDag path.
3004   MachineOperand &VDataIn = MI.getOperand(1);
3005   MachineOperand &VIndex = MI.getOperand(3);
3006   MachineOperand &VOffset = MI.getOperand(4);
3007   MachineOperand &SOffset = MI.getOperand(5);
3008   int16_t Offset = MI.getOperand(6).getImm();
3009 
3010   bool HasVOffset = !isOperandImmEqual(VOffset, 0, *MRI);
3011   bool HasVIndex = !isOperandImmEqual(VIndex, 0, *MRI);
3012 
3013   unsigned Opcode;
3014   if (HasVOffset) {
3015     Opcode = HasVIndex ? AMDGPU::BUFFER_ATOMIC_ADD_F32_BOTHEN
3016                        : AMDGPU::BUFFER_ATOMIC_ADD_F32_OFFEN;
3017   } else {
3018     Opcode = HasVIndex ? AMDGPU::BUFFER_ATOMIC_ADD_F32_IDXEN
3019                        : AMDGPU::BUFFER_ATOMIC_ADD_F32_OFFSET;
3020   }
3021 
3022   if (MRI->getType(VDataIn.getReg()).isVector()) {
3023     switch (Opcode) {
3024     case AMDGPU::BUFFER_ATOMIC_ADD_F32_BOTHEN:
3025       Opcode = AMDGPU::BUFFER_ATOMIC_PK_ADD_F16_BOTHEN;
3026       break;
3027     case AMDGPU::BUFFER_ATOMIC_ADD_F32_OFFEN:
3028       Opcode = AMDGPU::BUFFER_ATOMIC_PK_ADD_F16_OFFEN;
3029       break;
3030     case AMDGPU::BUFFER_ATOMIC_ADD_F32_IDXEN:
3031       Opcode = AMDGPU::BUFFER_ATOMIC_PK_ADD_F16_IDXEN;
3032       break;
3033     case AMDGPU::BUFFER_ATOMIC_ADD_F32_OFFSET:
3034       Opcode = AMDGPU::BUFFER_ATOMIC_PK_ADD_F16_OFFSET;
3035       break;
3036     }
3037   }
3038 
3039   auto I = BuildMI(*MBB, MI, DL, TII.get(Opcode));
3040   I.add(VDataIn);
3041 
3042   if (Opcode == AMDGPU::BUFFER_ATOMIC_ADD_F32_BOTHEN ||
3043       Opcode == AMDGPU::BUFFER_ATOMIC_PK_ADD_F16_BOTHEN) {
3044     Register IdxReg = MRI->createVirtualRegister(TRI.getVGPR64Class());
3045     BuildMI(*MBB, &*I, DL, TII.get(AMDGPU::REG_SEQUENCE), IdxReg)
3046       .addReg(VIndex.getReg())
3047       .addImm(AMDGPU::sub0)
3048       .addReg(VOffset.getReg())
3049       .addImm(AMDGPU::sub1);
3050 
3051     I.addReg(IdxReg);
3052   } else if (HasVIndex) {
3053     I.add(VIndex);
3054   } else if (HasVOffset) {
3055     I.add(VOffset);
3056   }
3057 
3058   I.add(MI.getOperand(2)); // rsrc
3059   I.add(SOffset);
3060   I.addImm(Offset);
3061   I.addImm(MI.getOperand(7).getImm()); // cpol
3062   I.cloneMemRefs(MI);
3063 
3064   MI.eraseFromParent();
3065 
3066   return true;
3067 }
3068 
3069 bool AMDGPUInstructionSelector::selectGlobalAtomicFadd(
3070   MachineInstr &MI, MachineOperand &AddrOp, MachineOperand &DataOp) const {
3071 
3072   if (STI.hasGFX90AInsts()) {
3073     // gfx90a adds return versions of the global atomic fadd instructions so no
3074     // special handling is required.
3075     return selectImpl(MI, *CoverageInfo);
3076   }
3077 
3078   MachineBasicBlock *MBB = MI.getParent();
3079   const DebugLoc &DL = MI.getDebugLoc();
3080 
3081   if (!MRI->use_nodbg_empty(MI.getOperand(0).getReg())) {
3082     Function &F = MBB->getParent()->getFunction();
3083     DiagnosticInfoUnsupported
3084       NoFpRet(F, "return versions of fp atomics not supported",
3085               MI.getDebugLoc(), DS_Error);
3086     F.getContext().diagnose(NoFpRet);
3087     return false;
3088   }
3089 
3090   // FIXME: This is only needed because tablegen requires number of dst operands
3091   // in match and replace pattern to be the same. Otherwise patterns can be
3092   // exported from SDag path.
3093   auto Addr = selectFlatOffsetImpl(AddrOp, SIInstrFlags::FlatGlobal);
3094 
3095   Register Data = DataOp.getReg();
3096   const unsigned Opc = MRI->getType(Data).isVector() ?
3097     AMDGPU::GLOBAL_ATOMIC_PK_ADD_F16 : AMDGPU::GLOBAL_ATOMIC_ADD_F32;
3098   auto MIB = BuildMI(*MBB, &MI, DL, TII.get(Opc))
3099     .addReg(Addr.first)
3100     .addReg(Data)
3101     .addImm(Addr.second)
3102     .addImm(0) // cpol
3103     .cloneMemRefs(MI);
3104 
3105   MI.eraseFromParent();
3106   return constrainSelectedInstRegOperands(*MIB, TII, TRI, RBI);
3107 }
3108 
3109 bool AMDGPUInstructionSelector::selectBVHIntrinsic(MachineInstr &MI) const{
3110   MI.setDesc(TII.get(MI.getOperand(1).getImm()));
3111   MI.RemoveOperand(1);
3112   MI.addImplicitDefUseOperands(*MI.getParent()->getParent());
3113   return true;
3114 }
3115 
3116 bool AMDGPUInstructionSelector::select(MachineInstr &I) {
3117   if (I.isPHI())
3118     return selectPHI(I);
3119 
3120   if (!I.isPreISelOpcode()) {
3121     if (I.isCopy())
3122       return selectCOPY(I);
3123     return true;
3124   }
3125 
3126   switch (I.getOpcode()) {
3127   case TargetOpcode::G_AND:
3128   case TargetOpcode::G_OR:
3129   case TargetOpcode::G_XOR:
3130     if (selectImpl(I, *CoverageInfo))
3131       return true;
3132     return selectG_AND_OR_XOR(I);
3133   case TargetOpcode::G_ADD:
3134   case TargetOpcode::G_SUB:
3135     if (selectImpl(I, *CoverageInfo))
3136       return true;
3137     return selectG_ADD_SUB(I);
3138   case TargetOpcode::G_UADDO:
3139   case TargetOpcode::G_USUBO:
3140   case TargetOpcode::G_UADDE:
3141   case TargetOpcode::G_USUBE:
3142     return selectG_UADDO_USUBO_UADDE_USUBE(I);
3143   case TargetOpcode::G_INTTOPTR:
3144   case TargetOpcode::G_BITCAST:
3145   case TargetOpcode::G_PTRTOINT:
3146     return selectCOPY(I);
3147   case TargetOpcode::G_CONSTANT:
3148   case TargetOpcode::G_FCONSTANT:
3149     return selectG_CONSTANT(I);
3150   case TargetOpcode::G_FNEG:
3151     if (selectImpl(I, *CoverageInfo))
3152       return true;
3153     return selectG_FNEG(I);
3154   case TargetOpcode::G_FABS:
3155     if (selectImpl(I, *CoverageInfo))
3156       return true;
3157     return selectG_FABS(I);
3158   case TargetOpcode::G_EXTRACT:
3159     return selectG_EXTRACT(I);
3160   case TargetOpcode::G_MERGE_VALUES:
3161   case TargetOpcode::G_BUILD_VECTOR:
3162   case TargetOpcode::G_CONCAT_VECTORS:
3163     return selectG_MERGE_VALUES(I);
3164   case TargetOpcode::G_UNMERGE_VALUES:
3165     return selectG_UNMERGE_VALUES(I);
3166   case TargetOpcode::G_BUILD_VECTOR_TRUNC:
3167     return selectG_BUILD_VECTOR_TRUNC(I);
3168   case TargetOpcode::G_PTR_ADD:
3169     return selectG_PTR_ADD(I);
3170   case TargetOpcode::G_IMPLICIT_DEF:
3171     return selectG_IMPLICIT_DEF(I);
3172   case TargetOpcode::G_FREEZE:
3173     return selectCOPY(I);
3174   case TargetOpcode::G_INSERT:
3175     return selectG_INSERT(I);
3176   case TargetOpcode::G_INTRINSIC:
3177     return selectG_INTRINSIC(I);
3178   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
3179     return selectG_INTRINSIC_W_SIDE_EFFECTS(I);
3180   case TargetOpcode::G_ICMP:
3181     if (selectG_ICMP(I))
3182       return true;
3183     return selectImpl(I, *CoverageInfo);
3184   case TargetOpcode::G_LOAD:
3185   case TargetOpcode::G_STORE:
3186   case TargetOpcode::G_ATOMIC_CMPXCHG:
3187   case TargetOpcode::G_ATOMICRMW_XCHG:
3188   case TargetOpcode::G_ATOMICRMW_ADD:
3189   case TargetOpcode::G_ATOMICRMW_SUB:
3190   case TargetOpcode::G_ATOMICRMW_AND:
3191   case TargetOpcode::G_ATOMICRMW_OR:
3192   case TargetOpcode::G_ATOMICRMW_XOR:
3193   case TargetOpcode::G_ATOMICRMW_MIN:
3194   case TargetOpcode::G_ATOMICRMW_MAX:
3195   case TargetOpcode::G_ATOMICRMW_UMIN:
3196   case TargetOpcode::G_ATOMICRMW_UMAX:
3197   case TargetOpcode::G_ATOMICRMW_FADD:
3198   case AMDGPU::G_AMDGPU_ATOMIC_INC:
3199   case AMDGPU::G_AMDGPU_ATOMIC_DEC:
3200   case AMDGPU::G_AMDGPU_ATOMIC_FMIN:
3201   case AMDGPU::G_AMDGPU_ATOMIC_FMAX:
3202     return selectG_LOAD_STORE_ATOMICRMW(I);
3203   case AMDGPU::G_AMDGPU_ATOMIC_CMPXCHG:
3204     return selectG_AMDGPU_ATOMIC_CMPXCHG(I);
3205   case TargetOpcode::G_SELECT:
3206     return selectG_SELECT(I);
3207   case TargetOpcode::G_TRUNC:
3208     return selectG_TRUNC(I);
3209   case TargetOpcode::G_SEXT:
3210   case TargetOpcode::G_ZEXT:
3211   case TargetOpcode::G_ANYEXT:
3212   case TargetOpcode::G_SEXT_INREG:
3213     if (selectImpl(I, *CoverageInfo))
3214       return true;
3215     return selectG_SZA_EXT(I);
3216   case TargetOpcode::G_BRCOND:
3217     return selectG_BRCOND(I);
3218   case TargetOpcode::G_GLOBAL_VALUE:
3219     return selectG_GLOBAL_VALUE(I);
3220   case TargetOpcode::G_PTRMASK:
3221     return selectG_PTRMASK(I);
3222   case TargetOpcode::G_EXTRACT_VECTOR_ELT:
3223     return selectG_EXTRACT_VECTOR_ELT(I);
3224   case TargetOpcode::G_INSERT_VECTOR_ELT:
3225     return selectG_INSERT_VECTOR_ELT(I);
3226   case TargetOpcode::G_SHUFFLE_VECTOR:
3227     return selectG_SHUFFLE_VECTOR(I);
3228   case AMDGPU::G_AMDGPU_INTRIN_IMAGE_LOAD:
3229   case AMDGPU::G_AMDGPU_INTRIN_IMAGE_LOAD_D16:
3230   case AMDGPU::G_AMDGPU_INTRIN_IMAGE_STORE:
3231   case AMDGPU::G_AMDGPU_INTRIN_IMAGE_STORE_D16: {
3232     const AMDGPU::ImageDimIntrinsicInfo *Intr
3233       = AMDGPU::getImageDimIntrinsicInfo(I.getIntrinsicID());
3234     assert(Intr && "not an image intrinsic with image pseudo");
3235     return selectImageIntrinsic(I, Intr);
3236   }
3237   case AMDGPU::G_AMDGPU_INTRIN_BVH_INTERSECT_RAY:
3238     return selectBVHIntrinsic(I);
3239   case AMDGPU::G_AMDGPU_BUFFER_ATOMIC_FADD:
3240     return selectAMDGPU_BUFFER_ATOMIC_FADD(I);
3241   case AMDGPU::G_SBFX:
3242   case AMDGPU::G_UBFX:
3243     return selectG_SBFX_UBFX(I);
3244   case AMDGPU::G_SI_CALL:
3245     I.setDesc(TII.get(AMDGPU::SI_CALL));
3246     return true;
3247   default:
3248     return selectImpl(I, *CoverageInfo);
3249   }
3250   return false;
3251 }
3252 
3253 InstructionSelector::ComplexRendererFns
3254 AMDGPUInstructionSelector::selectVCSRC(MachineOperand &Root) const {
3255   return {{
3256       [=](MachineInstrBuilder &MIB) { MIB.add(Root); }
3257   }};
3258 
3259 }
3260 
3261 std::pair<Register, unsigned>
3262 AMDGPUInstructionSelector::selectVOP3ModsImpl(MachineOperand &Root,
3263                                               bool AllowAbs) const {
3264   Register Src = Root.getReg();
3265   Register OrigSrc = Src;
3266   unsigned Mods = 0;
3267   MachineInstr *MI = getDefIgnoringCopies(Src, *MRI);
3268 
3269   if (MI && MI->getOpcode() == AMDGPU::G_FNEG) {
3270     Src = MI->getOperand(1).getReg();
3271     Mods |= SISrcMods::NEG;
3272     MI = getDefIgnoringCopies(Src, *MRI);
3273   }
3274 
3275   if (AllowAbs && MI && MI->getOpcode() == AMDGPU::G_FABS) {
3276     Src = MI->getOperand(1).getReg();
3277     Mods |= SISrcMods::ABS;
3278   }
3279 
3280   if (Mods != 0 &&
3281       RBI.getRegBank(Src, *MRI, TRI)->getID() != AMDGPU::VGPRRegBankID) {
3282     MachineInstr *UseMI = Root.getParent();
3283 
3284     // If we looked through copies to find source modifiers on an SGPR operand,
3285     // we now have an SGPR register source. To avoid potentially violating the
3286     // constant bus restriction, we need to insert a copy to a VGPR.
3287     Register VGPRSrc = MRI->cloneVirtualRegister(OrigSrc);
3288     BuildMI(*UseMI->getParent(), UseMI, UseMI->getDebugLoc(),
3289             TII.get(AMDGPU::COPY), VGPRSrc)
3290       .addReg(Src);
3291     Src = VGPRSrc;
3292   }
3293 
3294   return std::make_pair(Src, Mods);
3295 }
3296 
3297 ///
3298 /// This will select either an SGPR or VGPR operand and will save us from
3299 /// having to write an extra tablegen pattern.
3300 InstructionSelector::ComplexRendererFns
3301 AMDGPUInstructionSelector::selectVSRC0(MachineOperand &Root) const {
3302   return {{
3303       [=](MachineInstrBuilder &MIB) { MIB.add(Root); }
3304   }};
3305 }
3306 
3307 InstructionSelector::ComplexRendererFns
3308 AMDGPUInstructionSelector::selectVOP3Mods0(MachineOperand &Root) const {
3309   Register Src;
3310   unsigned Mods;
3311   std::tie(Src, Mods) = selectVOP3ModsImpl(Root);
3312 
3313   return {{
3314       [=](MachineInstrBuilder &MIB) { MIB.addReg(Src); },
3315       [=](MachineInstrBuilder &MIB) { MIB.addImm(Mods); }, // src0_mods
3316       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); },    // clamp
3317       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }     // omod
3318   }};
3319 }
3320 
3321 InstructionSelector::ComplexRendererFns
3322 AMDGPUInstructionSelector::selectVOP3BMods0(MachineOperand &Root) const {
3323   Register Src;
3324   unsigned Mods;
3325   std::tie(Src, Mods) = selectVOP3ModsImpl(Root, /* AllowAbs */ false);
3326 
3327   return {{
3328       [=](MachineInstrBuilder &MIB) { MIB.addReg(Src); },
3329       [=](MachineInstrBuilder &MIB) { MIB.addImm(Mods); }, // src0_mods
3330       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); },    // clamp
3331       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }     // omod
3332   }};
3333 }
3334 
3335 InstructionSelector::ComplexRendererFns
3336 AMDGPUInstructionSelector::selectVOP3OMods(MachineOperand &Root) const {
3337   return {{
3338       [=](MachineInstrBuilder &MIB) { MIB.add(Root); },
3339       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }, // clamp
3340       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }  // omod
3341   }};
3342 }
3343 
3344 InstructionSelector::ComplexRendererFns
3345 AMDGPUInstructionSelector::selectVOP3Mods(MachineOperand &Root) const {
3346   Register Src;
3347   unsigned Mods;
3348   std::tie(Src, Mods) = selectVOP3ModsImpl(Root);
3349 
3350   return {{
3351       [=](MachineInstrBuilder &MIB) { MIB.addReg(Src); },
3352       [=](MachineInstrBuilder &MIB) { MIB.addImm(Mods); }  // src_mods
3353   }};
3354 }
3355 
3356 InstructionSelector::ComplexRendererFns
3357 AMDGPUInstructionSelector::selectVOP3BMods(MachineOperand &Root) const {
3358   Register Src;
3359   unsigned Mods;
3360   std::tie(Src, Mods) = selectVOP3ModsImpl(Root, /* AllowAbs */ false);
3361 
3362   return {{
3363       [=](MachineInstrBuilder &MIB) { MIB.addReg(Src); },
3364       [=](MachineInstrBuilder &MIB) { MIB.addImm(Mods); } // src_mods
3365   }};
3366 }
3367 
3368 InstructionSelector::ComplexRendererFns
3369 AMDGPUInstructionSelector::selectVOP3NoMods(MachineOperand &Root) const {
3370   Register Reg = Root.getReg();
3371   const MachineInstr *Def = getDefIgnoringCopies(Reg, *MRI);
3372   if (Def && (Def->getOpcode() == AMDGPU::G_FNEG ||
3373               Def->getOpcode() == AMDGPU::G_FABS))
3374     return {};
3375   return {{
3376       [=](MachineInstrBuilder &MIB) { MIB.addReg(Reg); },
3377   }};
3378 }
3379 
3380 std::pair<Register, unsigned>
3381 AMDGPUInstructionSelector::selectVOP3PModsImpl(
3382   Register Src, const MachineRegisterInfo &MRI) const {
3383   unsigned Mods = 0;
3384   MachineInstr *MI = MRI.getVRegDef(Src);
3385 
3386   if (MI && MI->getOpcode() == AMDGPU::G_FNEG &&
3387       // It's possible to see an f32 fneg here, but unlikely.
3388       // TODO: Treat f32 fneg as only high bit.
3389       MRI.getType(Src) == LLT::fixed_vector(2, 16)) {
3390     Mods ^= (SISrcMods::NEG | SISrcMods::NEG_HI);
3391     Src = MI->getOperand(1).getReg();
3392     MI = MRI.getVRegDef(Src);
3393   }
3394 
3395   // TODO: Match op_sel through g_build_vector_trunc and g_shuffle_vector.
3396 
3397   // Packed instructions do not have abs modifiers.
3398   Mods |= SISrcMods::OP_SEL_1;
3399 
3400   return std::make_pair(Src, Mods);
3401 }
3402 
3403 InstructionSelector::ComplexRendererFns
3404 AMDGPUInstructionSelector::selectVOP3PMods(MachineOperand &Root) const {
3405   MachineRegisterInfo &MRI
3406     = Root.getParent()->getParent()->getParent()->getRegInfo();
3407 
3408   Register Src;
3409   unsigned Mods;
3410   std::tie(Src, Mods) = selectVOP3PModsImpl(Root.getReg(), MRI);
3411 
3412   return {{
3413       [=](MachineInstrBuilder &MIB) { MIB.addReg(Src); },
3414       [=](MachineInstrBuilder &MIB) { MIB.addImm(Mods); }  // src_mods
3415   }};
3416 }
3417 
3418 InstructionSelector::ComplexRendererFns
3419 AMDGPUInstructionSelector::selectVOP3Mods_nnan(MachineOperand &Root) const {
3420   Register Src;
3421   unsigned Mods;
3422   std::tie(Src, Mods) = selectVOP3ModsImpl(Root);
3423   if (!isKnownNeverNaN(Src, *MRI))
3424     return None;
3425 
3426   return {{
3427       [=](MachineInstrBuilder &MIB) { MIB.addReg(Src); },
3428       [=](MachineInstrBuilder &MIB) { MIB.addImm(Mods); }  // src_mods
3429   }};
3430 }
3431 
3432 InstructionSelector::ComplexRendererFns
3433 AMDGPUInstructionSelector::selectVOP3OpSelMods(MachineOperand &Root) const {
3434   // FIXME: Handle op_sel
3435   return {{
3436       [=](MachineInstrBuilder &MIB) { MIB.addReg(Root.getReg()); },
3437       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); } // src_mods
3438   }};
3439 }
3440 
3441 InstructionSelector::ComplexRendererFns
3442 AMDGPUInstructionSelector::selectSmrdImm(MachineOperand &Root) const {
3443   SmallVector<GEPInfo, 4> AddrInfo;
3444   getAddrModeInfo(*Root.getParent(), *MRI, AddrInfo);
3445 
3446   if (AddrInfo.empty() || AddrInfo[0].SgprParts.size() != 1)
3447     return None;
3448 
3449   const GEPInfo &GEPInfo = AddrInfo[0];
3450   Optional<int64_t> EncodedImm =
3451       AMDGPU::getSMRDEncodedOffset(STI, GEPInfo.Imm, false);
3452   if (!EncodedImm)
3453     return None;
3454 
3455   unsigned PtrReg = GEPInfo.SgprParts[0];
3456   return {{
3457     [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrReg); },
3458     [=](MachineInstrBuilder &MIB) { MIB.addImm(*EncodedImm); }
3459   }};
3460 }
3461 
3462 InstructionSelector::ComplexRendererFns
3463 AMDGPUInstructionSelector::selectSmrdImm32(MachineOperand &Root) const {
3464   SmallVector<GEPInfo, 4> AddrInfo;
3465   getAddrModeInfo(*Root.getParent(), *MRI, AddrInfo);
3466 
3467   if (AddrInfo.empty() || AddrInfo[0].SgprParts.size() != 1)
3468     return None;
3469 
3470   const GEPInfo &GEPInfo = AddrInfo[0];
3471   Register PtrReg = GEPInfo.SgprParts[0];
3472   Optional<int64_t> EncodedImm =
3473       AMDGPU::getSMRDEncodedLiteralOffset32(STI, GEPInfo.Imm);
3474   if (!EncodedImm)
3475     return None;
3476 
3477   return {{
3478     [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrReg); },
3479     [=](MachineInstrBuilder &MIB) { MIB.addImm(*EncodedImm); }
3480   }};
3481 }
3482 
3483 InstructionSelector::ComplexRendererFns
3484 AMDGPUInstructionSelector::selectSmrdSgpr(MachineOperand &Root) const {
3485   MachineInstr *MI = Root.getParent();
3486   MachineBasicBlock *MBB = MI->getParent();
3487 
3488   SmallVector<GEPInfo, 4> AddrInfo;
3489   getAddrModeInfo(*MI, *MRI, AddrInfo);
3490 
3491   // FIXME: We should shrink the GEP if the offset is known to be <= 32-bits,
3492   // then we can select all ptr + 32-bit offsets not just immediate offsets.
3493   if (AddrInfo.empty() || AddrInfo[0].SgprParts.size() != 1)
3494     return None;
3495 
3496   const GEPInfo &GEPInfo = AddrInfo[0];
3497   // SGPR offset is unsigned.
3498   if (!GEPInfo.Imm || GEPInfo.Imm < 0 || !isUInt<32>(GEPInfo.Imm))
3499     return None;
3500 
3501   // If we make it this far we have a load with an 32-bit immediate offset.
3502   // It is OK to select this using a sgpr offset, because we have already
3503   // failed trying to select this load into one of the _IMM variants since
3504   // the _IMM Patterns are considered before the _SGPR patterns.
3505   Register PtrReg = GEPInfo.SgprParts[0];
3506   Register OffsetReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
3507   BuildMI(*MBB, MI, MI->getDebugLoc(), TII.get(AMDGPU::S_MOV_B32), OffsetReg)
3508           .addImm(GEPInfo.Imm);
3509   return {{
3510     [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrReg); },
3511     [=](MachineInstrBuilder &MIB) { MIB.addReg(OffsetReg); }
3512   }};
3513 }
3514 
3515 std::pair<Register, int>
3516 AMDGPUInstructionSelector::selectFlatOffsetImpl(MachineOperand &Root,
3517                                                 uint64_t FlatVariant) const {
3518   MachineInstr *MI = Root.getParent();
3519 
3520   auto Default = std::make_pair(Root.getReg(), 0);
3521 
3522   if (!STI.hasFlatInstOffsets())
3523     return Default;
3524 
3525   Register PtrBase;
3526   int64_t ConstOffset;
3527   std::tie(PtrBase, ConstOffset) =
3528       getPtrBaseWithConstantOffset(Root.getReg(), *MRI);
3529   if (ConstOffset == 0)
3530     return Default;
3531 
3532   unsigned AddrSpace = (*MI->memoperands_begin())->getAddrSpace();
3533   if (!TII.isLegalFLATOffset(ConstOffset, AddrSpace, FlatVariant))
3534     return Default;
3535 
3536   return std::make_pair(PtrBase, ConstOffset);
3537 }
3538 
3539 InstructionSelector::ComplexRendererFns
3540 AMDGPUInstructionSelector::selectFlatOffset(MachineOperand &Root) const {
3541   auto PtrWithOffset = selectFlatOffsetImpl(Root, SIInstrFlags::FLAT);
3542 
3543   return {{
3544       [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrWithOffset.first); },
3545       [=](MachineInstrBuilder &MIB) { MIB.addImm(PtrWithOffset.second); },
3546     }};
3547 }
3548 
3549 InstructionSelector::ComplexRendererFns
3550 AMDGPUInstructionSelector::selectGlobalOffset(MachineOperand &Root) const {
3551   auto PtrWithOffset = selectFlatOffsetImpl(Root, SIInstrFlags::FlatGlobal);
3552 
3553   return {{
3554       [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrWithOffset.first); },
3555       [=](MachineInstrBuilder &MIB) { MIB.addImm(PtrWithOffset.second); },
3556   }};
3557 }
3558 
3559 InstructionSelector::ComplexRendererFns
3560 AMDGPUInstructionSelector::selectScratchOffset(MachineOperand &Root) const {
3561   auto PtrWithOffset = selectFlatOffsetImpl(Root, SIInstrFlags::FlatScratch);
3562 
3563   return {{
3564       [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrWithOffset.first); },
3565       [=](MachineInstrBuilder &MIB) { MIB.addImm(PtrWithOffset.second); },
3566     }};
3567 }
3568 
3569 /// Match a zero extend from a 32-bit value to 64-bits.
3570 static Register matchZeroExtendFromS32(MachineRegisterInfo &MRI, Register Reg) {
3571   Register ZExtSrc;
3572   if (mi_match(Reg, MRI, m_GZExt(m_Reg(ZExtSrc))))
3573     return MRI.getType(ZExtSrc) == LLT::scalar(32) ? ZExtSrc : Register();
3574 
3575   // Match legalized form %zext = G_MERGE_VALUES (s32 %x), (s32 0)
3576   const MachineInstr *Def = getDefIgnoringCopies(Reg, MRI);
3577   if (Def->getOpcode() != AMDGPU::G_MERGE_VALUES)
3578     return false;
3579 
3580   if (mi_match(Def->getOperand(2).getReg(), MRI, m_ZeroInt())) {
3581     return Def->getOperand(1).getReg();
3582   }
3583 
3584   return Register();
3585 }
3586 
3587 // Match (64-bit SGPR base) + (zext vgpr offset) + sext(imm offset)
3588 InstructionSelector::ComplexRendererFns
3589 AMDGPUInstructionSelector::selectGlobalSAddr(MachineOperand &Root) const {
3590   Register Addr = Root.getReg();
3591   Register PtrBase;
3592   int64_t ConstOffset;
3593   int64_t ImmOffset = 0;
3594 
3595   // Match the immediate offset first, which canonically is moved as low as
3596   // possible.
3597   std::tie(PtrBase, ConstOffset) = getPtrBaseWithConstantOffset(Addr, *MRI);
3598 
3599   if (ConstOffset != 0) {
3600     if (TII.isLegalFLATOffset(ConstOffset, AMDGPUAS::GLOBAL_ADDRESS,
3601                               SIInstrFlags::FlatGlobal)) {
3602       Addr = PtrBase;
3603       ImmOffset = ConstOffset;
3604     } else {
3605       auto PtrBaseDef = getDefSrcRegIgnoringCopies(PtrBase, *MRI);
3606       if (!PtrBaseDef)
3607         return None;
3608 
3609       if (isSGPR(PtrBaseDef->Reg)) {
3610         if (ConstOffset > 0) {
3611           // Offset is too large.
3612           //
3613           // saddr + large_offset -> saddr +
3614           //                         (voffset = large_offset & ~MaxOffset) +
3615           //                         (large_offset & MaxOffset);
3616           int64_t SplitImmOffset, RemainderOffset;
3617           std::tie(SplitImmOffset, RemainderOffset) = TII.splitFlatOffset(
3618               ConstOffset, AMDGPUAS::GLOBAL_ADDRESS, SIInstrFlags::FlatGlobal);
3619 
3620           if (isUInt<32>(RemainderOffset)) {
3621             MachineInstr *MI = Root.getParent();
3622             MachineBasicBlock *MBB = MI->getParent();
3623             Register HighBits =
3624                 MRI->createVirtualRegister(&AMDGPU::VGPR_32RegClass);
3625 
3626             BuildMI(*MBB, MI, MI->getDebugLoc(), TII.get(AMDGPU::V_MOV_B32_e32),
3627                     HighBits)
3628                 .addImm(RemainderOffset);
3629 
3630             return {{
3631                 [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrBase); }, // saddr
3632                 [=](MachineInstrBuilder &MIB) {
3633                   MIB.addReg(HighBits);
3634                 }, // voffset
3635                 [=](MachineInstrBuilder &MIB) { MIB.addImm(SplitImmOffset); },
3636             }};
3637           }
3638         }
3639 
3640         // We are adding a 64 bit SGPR and a constant. If constant bus limit
3641         // is 1 we would need to perform 1 or 2 extra moves for each half of
3642         // the constant and it is better to do a scalar add and then issue a
3643         // single VALU instruction to materialize zero. Otherwise it is less
3644         // instructions to perform VALU adds with immediates or inline literals.
3645         unsigned NumLiterals =
3646             !TII.isInlineConstant(APInt(32, ConstOffset & 0xffffffff)) +
3647             !TII.isInlineConstant(APInt(32, ConstOffset >> 32));
3648         if (STI.getConstantBusLimit(AMDGPU::V_ADD_U32_e64) > NumLiterals)
3649           return None;
3650       }
3651     }
3652   }
3653 
3654   auto AddrDef = getDefSrcRegIgnoringCopies(Addr, *MRI);
3655   if (!AddrDef)
3656     return None;
3657 
3658   // Match the variable offset.
3659   if (AddrDef->MI->getOpcode() == AMDGPU::G_PTR_ADD) {
3660     // Look through the SGPR->VGPR copy.
3661     Register SAddr =
3662         getSrcRegIgnoringCopies(AddrDef->MI->getOperand(1).getReg(), *MRI);
3663 
3664     if (SAddr && isSGPR(SAddr)) {
3665       Register PtrBaseOffset = AddrDef->MI->getOperand(2).getReg();
3666 
3667       // It's possible voffset is an SGPR here, but the copy to VGPR will be
3668       // inserted later.
3669       if (Register VOffset = matchZeroExtendFromS32(*MRI, PtrBaseOffset)) {
3670         return {{[=](MachineInstrBuilder &MIB) { // saddr
3671                    MIB.addReg(SAddr);
3672                  },
3673                  [=](MachineInstrBuilder &MIB) { // voffset
3674                    MIB.addReg(VOffset);
3675                  },
3676                  [=](MachineInstrBuilder &MIB) { // offset
3677                    MIB.addImm(ImmOffset);
3678                  }}};
3679       }
3680     }
3681   }
3682 
3683   // FIXME: We should probably have folded COPY (G_IMPLICIT_DEF) earlier, and
3684   // drop this.
3685   if (AddrDef->MI->getOpcode() == AMDGPU::G_IMPLICIT_DEF ||
3686       AddrDef->MI->getOpcode() == AMDGPU::G_CONSTANT || !isSGPR(AddrDef->Reg))
3687     return None;
3688 
3689   // It's cheaper to materialize a single 32-bit zero for vaddr than the two
3690   // moves required to copy a 64-bit SGPR to VGPR.
3691   MachineInstr *MI = Root.getParent();
3692   MachineBasicBlock *MBB = MI->getParent();
3693   Register VOffset = MRI->createVirtualRegister(&AMDGPU::VGPR_32RegClass);
3694 
3695   BuildMI(*MBB, MI, MI->getDebugLoc(), TII.get(AMDGPU::V_MOV_B32_e32), VOffset)
3696       .addImm(0);
3697 
3698   return {{
3699       [=](MachineInstrBuilder &MIB) { MIB.addReg(AddrDef->Reg); }, // saddr
3700       [=](MachineInstrBuilder &MIB) { MIB.addReg(VOffset); },      // voffset
3701       [=](MachineInstrBuilder &MIB) { MIB.addImm(ImmOffset); }     // offset
3702   }};
3703 }
3704 
3705 InstructionSelector::ComplexRendererFns
3706 AMDGPUInstructionSelector::selectScratchSAddr(MachineOperand &Root) const {
3707   Register Addr = Root.getReg();
3708   Register PtrBase;
3709   int64_t ConstOffset;
3710   int64_t ImmOffset = 0;
3711 
3712   // Match the immediate offset first, which canonically is moved as low as
3713   // possible.
3714   std::tie(PtrBase, ConstOffset) = getPtrBaseWithConstantOffset(Addr, *MRI);
3715 
3716   if (ConstOffset != 0 &&
3717       TII.isLegalFLATOffset(ConstOffset, AMDGPUAS::PRIVATE_ADDRESS,
3718                             SIInstrFlags::FlatScratch)) {
3719     Addr = PtrBase;
3720     ImmOffset = ConstOffset;
3721   }
3722 
3723   auto AddrDef = getDefSrcRegIgnoringCopies(Addr, *MRI);
3724   if (!AddrDef)
3725     return None;
3726 
3727   if (AddrDef->MI->getOpcode() == AMDGPU::G_FRAME_INDEX) {
3728     int FI = AddrDef->MI->getOperand(1).getIndex();
3729     return {{
3730         [=](MachineInstrBuilder &MIB) { MIB.addFrameIndex(FI); }, // saddr
3731         [=](MachineInstrBuilder &MIB) { MIB.addImm(ImmOffset); } // offset
3732     }};
3733   }
3734 
3735   Register SAddr = AddrDef->Reg;
3736 
3737   if (AddrDef->MI->getOpcode() == AMDGPU::G_PTR_ADD) {
3738     Register LHS = AddrDef->MI->getOperand(1).getReg();
3739     Register RHS = AddrDef->MI->getOperand(2).getReg();
3740     auto LHSDef = getDefSrcRegIgnoringCopies(LHS, *MRI);
3741     auto RHSDef = getDefSrcRegIgnoringCopies(RHS, *MRI);
3742 
3743     if (LHSDef && RHSDef &&
3744         LHSDef->MI->getOpcode() == AMDGPU::G_FRAME_INDEX &&
3745         isSGPR(RHSDef->Reg)) {
3746       int FI = LHSDef->MI->getOperand(1).getIndex();
3747       MachineInstr &I = *Root.getParent();
3748       MachineBasicBlock *BB = I.getParent();
3749       const DebugLoc &DL = I.getDebugLoc();
3750       SAddr = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
3751 
3752       BuildMI(*BB, &I, DL, TII.get(AMDGPU::S_ADD_I32), SAddr)
3753           .addFrameIndex(FI)
3754           .addReg(RHSDef->Reg);
3755     }
3756   }
3757 
3758   if (!isSGPR(SAddr))
3759     return None;
3760 
3761   return {{
3762       [=](MachineInstrBuilder &MIB) { MIB.addReg(SAddr); }, // saddr
3763       [=](MachineInstrBuilder &MIB) { MIB.addImm(ImmOffset); } // offset
3764   }};
3765 }
3766 
3767 InstructionSelector::ComplexRendererFns
3768 AMDGPUInstructionSelector::selectMUBUFScratchOffen(MachineOperand &Root) const {
3769   MachineInstr *MI = Root.getParent();
3770   MachineBasicBlock *MBB = MI->getParent();
3771   MachineFunction *MF = MBB->getParent();
3772   const SIMachineFunctionInfo *Info = MF->getInfo<SIMachineFunctionInfo>();
3773 
3774   int64_t Offset = 0;
3775   if (mi_match(Root.getReg(), *MRI, m_ICst(Offset)) &&
3776       Offset != TM.getNullPointerValue(AMDGPUAS::PRIVATE_ADDRESS)) {
3777     Register HighBits = MRI->createVirtualRegister(&AMDGPU::VGPR_32RegClass);
3778 
3779     // TODO: Should this be inside the render function? The iterator seems to
3780     // move.
3781     BuildMI(*MBB, MI, MI->getDebugLoc(), TII.get(AMDGPU::V_MOV_B32_e32),
3782             HighBits)
3783       .addImm(Offset & ~4095);
3784 
3785     return {{[=](MachineInstrBuilder &MIB) { // rsrc
3786                MIB.addReg(Info->getScratchRSrcReg());
3787              },
3788              [=](MachineInstrBuilder &MIB) { // vaddr
3789                MIB.addReg(HighBits);
3790              },
3791              [=](MachineInstrBuilder &MIB) { // soffset
3792                // Use constant zero for soffset and rely on eliminateFrameIndex
3793                // to choose the appropriate frame register if need be.
3794                MIB.addImm(0);
3795              },
3796              [=](MachineInstrBuilder &MIB) { // offset
3797                MIB.addImm(Offset & 4095);
3798              }}};
3799   }
3800 
3801   assert(Offset == 0 || Offset == -1);
3802 
3803   // Try to fold a frame index directly into the MUBUF vaddr field, and any
3804   // offsets.
3805   Optional<int> FI;
3806   Register VAddr = Root.getReg();
3807   if (const MachineInstr *RootDef = MRI->getVRegDef(Root.getReg())) {
3808     Register PtrBase;
3809     int64_t ConstOffset;
3810     std::tie(PtrBase, ConstOffset) = getPtrBaseWithConstantOffset(VAddr, *MRI);
3811     if (ConstOffset != 0) {
3812       if (SIInstrInfo::isLegalMUBUFImmOffset(ConstOffset) &&
3813           (!STI.privateMemoryResourceIsRangeChecked() ||
3814            KnownBits->signBitIsZero(PtrBase))) {
3815         const MachineInstr *PtrBaseDef = MRI->getVRegDef(PtrBase);
3816         if (PtrBaseDef->getOpcode() == AMDGPU::G_FRAME_INDEX)
3817           FI = PtrBaseDef->getOperand(1).getIndex();
3818         else
3819           VAddr = PtrBase;
3820         Offset = ConstOffset;
3821       }
3822     } else if (RootDef->getOpcode() == AMDGPU::G_FRAME_INDEX) {
3823       FI = RootDef->getOperand(1).getIndex();
3824     }
3825   }
3826 
3827   return {{[=](MachineInstrBuilder &MIB) { // rsrc
3828              MIB.addReg(Info->getScratchRSrcReg());
3829            },
3830            [=](MachineInstrBuilder &MIB) { // vaddr
3831              if (FI.hasValue())
3832                MIB.addFrameIndex(FI.getValue());
3833              else
3834                MIB.addReg(VAddr);
3835            },
3836            [=](MachineInstrBuilder &MIB) { // soffset
3837              // Use constant zero for soffset and rely on eliminateFrameIndex
3838              // to choose the appropriate frame register if need be.
3839              MIB.addImm(0);
3840            },
3841            [=](MachineInstrBuilder &MIB) { // offset
3842              MIB.addImm(Offset);
3843            }}};
3844 }
3845 
3846 bool AMDGPUInstructionSelector::isDSOffsetLegal(Register Base,
3847                                                 int64_t Offset) const {
3848   if (!isUInt<16>(Offset))
3849     return false;
3850 
3851   if (STI.hasUsableDSOffset() || STI.unsafeDSOffsetFoldingEnabled())
3852     return true;
3853 
3854   // On Southern Islands instruction with a negative base value and an offset
3855   // don't seem to work.
3856   return KnownBits->signBitIsZero(Base);
3857 }
3858 
3859 bool AMDGPUInstructionSelector::isDSOffset2Legal(Register Base, int64_t Offset0,
3860                                                  int64_t Offset1,
3861                                                  unsigned Size) const {
3862   if (Offset0 % Size != 0 || Offset1 % Size != 0)
3863     return false;
3864   if (!isUInt<8>(Offset0 / Size) || !isUInt<8>(Offset1 / Size))
3865     return false;
3866 
3867   if (STI.hasUsableDSOffset() || STI.unsafeDSOffsetFoldingEnabled())
3868     return true;
3869 
3870   // On Southern Islands instruction with a negative base value and an offset
3871   // don't seem to work.
3872   return KnownBits->signBitIsZero(Base);
3873 }
3874 
3875 bool AMDGPUInstructionSelector::isUnneededShiftMask(const MachineInstr &MI,
3876                                                     unsigned ShAmtBits) const {
3877   assert(MI.getOpcode() == TargetOpcode::G_AND);
3878 
3879   Optional<APInt> RHS = getIConstantVRegVal(MI.getOperand(2).getReg(), *MRI);
3880   if (!RHS)
3881     return false;
3882 
3883   if (RHS->countTrailingOnes() >= ShAmtBits)
3884     return true;
3885 
3886   const APInt &LHSKnownZeros =
3887       KnownBits->getKnownZeroes(MI.getOperand(1).getReg());
3888   return (LHSKnownZeros | *RHS).countTrailingOnes() >= ShAmtBits;
3889 }
3890 
3891 InstructionSelector::ComplexRendererFns
3892 AMDGPUInstructionSelector::selectMUBUFScratchOffset(
3893     MachineOperand &Root) const {
3894   MachineInstr *MI = Root.getParent();
3895   MachineBasicBlock *MBB = MI->getParent();
3896 
3897   int64_t Offset = 0;
3898   if (!mi_match(Root.getReg(), *MRI, m_ICst(Offset)) ||
3899       !SIInstrInfo::isLegalMUBUFImmOffset(Offset))
3900     return {};
3901 
3902   const MachineFunction *MF = MBB->getParent();
3903   const SIMachineFunctionInfo *Info = MF->getInfo<SIMachineFunctionInfo>();
3904 
3905   return {{
3906       [=](MachineInstrBuilder &MIB) { // rsrc
3907         MIB.addReg(Info->getScratchRSrcReg());
3908       },
3909       [=](MachineInstrBuilder &MIB) { // soffset
3910         MIB.addImm(0);
3911       },
3912       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); } // offset
3913   }};
3914 }
3915 
3916 std::pair<Register, unsigned>
3917 AMDGPUInstructionSelector::selectDS1Addr1OffsetImpl(MachineOperand &Root) const {
3918   const MachineInstr *RootDef = MRI->getVRegDef(Root.getReg());
3919   if (!RootDef)
3920     return std::make_pair(Root.getReg(), 0);
3921 
3922   int64_t ConstAddr = 0;
3923 
3924   Register PtrBase;
3925   int64_t Offset;
3926   std::tie(PtrBase, Offset) =
3927     getPtrBaseWithConstantOffset(Root.getReg(), *MRI);
3928 
3929   if (Offset) {
3930     if (isDSOffsetLegal(PtrBase, Offset)) {
3931       // (add n0, c0)
3932       return std::make_pair(PtrBase, Offset);
3933     }
3934   } else if (RootDef->getOpcode() == AMDGPU::G_SUB) {
3935     // TODO
3936 
3937 
3938   } else if (mi_match(Root.getReg(), *MRI, m_ICst(ConstAddr))) {
3939     // TODO
3940 
3941   }
3942 
3943   return std::make_pair(Root.getReg(), 0);
3944 }
3945 
3946 InstructionSelector::ComplexRendererFns
3947 AMDGPUInstructionSelector::selectDS1Addr1Offset(MachineOperand &Root) const {
3948   Register Reg;
3949   unsigned Offset;
3950   std::tie(Reg, Offset) = selectDS1Addr1OffsetImpl(Root);
3951   return {{
3952       [=](MachineInstrBuilder &MIB) { MIB.addReg(Reg); },
3953       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); }
3954     }};
3955 }
3956 
3957 InstructionSelector::ComplexRendererFns
3958 AMDGPUInstructionSelector::selectDS64Bit4ByteAligned(MachineOperand &Root) const {
3959   return selectDSReadWrite2(Root, 4);
3960 }
3961 
3962 InstructionSelector::ComplexRendererFns
3963 AMDGPUInstructionSelector::selectDS128Bit8ByteAligned(MachineOperand &Root) const {
3964   return selectDSReadWrite2(Root, 8);
3965 }
3966 
3967 InstructionSelector::ComplexRendererFns
3968 AMDGPUInstructionSelector::selectDSReadWrite2(MachineOperand &Root,
3969                                               unsigned Size) const {
3970   Register Reg;
3971   unsigned Offset;
3972   std::tie(Reg, Offset) = selectDSReadWrite2Impl(Root, Size);
3973   return {{
3974       [=](MachineInstrBuilder &MIB) { MIB.addReg(Reg); },
3975       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); },
3976       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset+1); }
3977     }};
3978 }
3979 
3980 std::pair<Register, unsigned>
3981 AMDGPUInstructionSelector::selectDSReadWrite2Impl(MachineOperand &Root,
3982                                                   unsigned Size) const {
3983   const MachineInstr *RootDef = MRI->getVRegDef(Root.getReg());
3984   if (!RootDef)
3985     return std::make_pair(Root.getReg(), 0);
3986 
3987   int64_t ConstAddr = 0;
3988 
3989   Register PtrBase;
3990   int64_t Offset;
3991   std::tie(PtrBase, Offset) =
3992     getPtrBaseWithConstantOffset(Root.getReg(), *MRI);
3993 
3994   if (Offset) {
3995     int64_t OffsetValue0 = Offset;
3996     int64_t OffsetValue1 = Offset + Size;
3997     if (isDSOffset2Legal(PtrBase, OffsetValue0, OffsetValue1, Size)) {
3998       // (add n0, c0)
3999       return std::make_pair(PtrBase, OffsetValue0 / Size);
4000     }
4001   } else if (RootDef->getOpcode() == AMDGPU::G_SUB) {
4002     // TODO
4003 
4004   } else if (mi_match(Root.getReg(), *MRI, m_ICst(ConstAddr))) {
4005     // TODO
4006 
4007   }
4008 
4009   return std::make_pair(Root.getReg(), 0);
4010 }
4011 
4012 /// If \p Root is a G_PTR_ADD with a G_CONSTANT on the right hand side, return
4013 /// the base value with the constant offset. There may be intervening copies
4014 /// between \p Root and the identified constant. Returns \p Root, 0 if this does
4015 /// not match the pattern.
4016 std::pair<Register, int64_t>
4017 AMDGPUInstructionSelector::getPtrBaseWithConstantOffset(
4018   Register Root, const MachineRegisterInfo &MRI) const {
4019   MachineInstr *RootI = getDefIgnoringCopies(Root, MRI);
4020   if (RootI->getOpcode() != TargetOpcode::G_PTR_ADD)
4021     return {Root, 0};
4022 
4023   MachineOperand &RHS = RootI->getOperand(2);
4024   Optional<ValueAndVReg> MaybeOffset =
4025       getIConstantVRegValWithLookThrough(RHS.getReg(), MRI);
4026   if (!MaybeOffset)
4027     return {Root, 0};
4028   return {RootI->getOperand(1).getReg(), MaybeOffset->Value.getSExtValue()};
4029 }
4030 
4031 static void addZeroImm(MachineInstrBuilder &MIB) {
4032   MIB.addImm(0);
4033 }
4034 
4035 /// Return a resource descriptor for use with an arbitrary 64-bit pointer. If \p
4036 /// BasePtr is not valid, a null base pointer will be used.
4037 static Register buildRSRC(MachineIRBuilder &B, MachineRegisterInfo &MRI,
4038                           uint32_t FormatLo, uint32_t FormatHi,
4039                           Register BasePtr) {
4040   Register RSrc2 = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
4041   Register RSrc3 = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
4042   Register RSrcHi = MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass);
4043   Register RSrc = MRI.createVirtualRegister(&AMDGPU::SGPR_128RegClass);
4044 
4045   B.buildInstr(AMDGPU::S_MOV_B32)
4046     .addDef(RSrc2)
4047     .addImm(FormatLo);
4048   B.buildInstr(AMDGPU::S_MOV_B32)
4049     .addDef(RSrc3)
4050     .addImm(FormatHi);
4051 
4052   // Build the half of the subregister with the constants before building the
4053   // full 128-bit register. If we are building multiple resource descriptors,
4054   // this will allow CSEing of the 2-component register.
4055   B.buildInstr(AMDGPU::REG_SEQUENCE)
4056     .addDef(RSrcHi)
4057     .addReg(RSrc2)
4058     .addImm(AMDGPU::sub0)
4059     .addReg(RSrc3)
4060     .addImm(AMDGPU::sub1);
4061 
4062   Register RSrcLo = BasePtr;
4063   if (!BasePtr) {
4064     RSrcLo = MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass);
4065     B.buildInstr(AMDGPU::S_MOV_B64)
4066       .addDef(RSrcLo)
4067       .addImm(0);
4068   }
4069 
4070   B.buildInstr(AMDGPU::REG_SEQUENCE)
4071     .addDef(RSrc)
4072     .addReg(RSrcLo)
4073     .addImm(AMDGPU::sub0_sub1)
4074     .addReg(RSrcHi)
4075     .addImm(AMDGPU::sub2_sub3);
4076 
4077   return RSrc;
4078 }
4079 
4080 static Register buildAddr64RSrc(MachineIRBuilder &B, MachineRegisterInfo &MRI,
4081                                 const SIInstrInfo &TII, Register BasePtr) {
4082   uint64_t DefaultFormat = TII.getDefaultRsrcDataFormat();
4083 
4084   // FIXME: Why are half the "default" bits ignored based on the addressing
4085   // mode?
4086   return buildRSRC(B, MRI, 0, Hi_32(DefaultFormat), BasePtr);
4087 }
4088 
4089 static Register buildOffsetSrc(MachineIRBuilder &B, MachineRegisterInfo &MRI,
4090                                const SIInstrInfo &TII, Register BasePtr) {
4091   uint64_t DefaultFormat = TII.getDefaultRsrcDataFormat();
4092 
4093   // FIXME: Why are half the "default" bits ignored based on the addressing
4094   // mode?
4095   return buildRSRC(B, MRI, -1, Hi_32(DefaultFormat), BasePtr);
4096 }
4097 
4098 AMDGPUInstructionSelector::MUBUFAddressData
4099 AMDGPUInstructionSelector::parseMUBUFAddress(Register Src) const {
4100   MUBUFAddressData Data;
4101   Data.N0 = Src;
4102 
4103   Register PtrBase;
4104   int64_t Offset;
4105 
4106   std::tie(PtrBase, Offset) = getPtrBaseWithConstantOffset(Src, *MRI);
4107   if (isUInt<32>(Offset)) {
4108     Data.N0 = PtrBase;
4109     Data.Offset = Offset;
4110   }
4111 
4112   if (MachineInstr *InputAdd
4113       = getOpcodeDef(TargetOpcode::G_PTR_ADD, Data.N0, *MRI)) {
4114     Data.N2 = InputAdd->getOperand(1).getReg();
4115     Data.N3 = InputAdd->getOperand(2).getReg();
4116 
4117     // FIXME: Need to fix extra SGPR->VGPRcopies inserted
4118     // FIXME: Don't know this was defined by operand 0
4119     //
4120     // TODO: Remove this when we have copy folding optimizations after
4121     // RegBankSelect.
4122     Data.N2 = getDefIgnoringCopies(Data.N2, *MRI)->getOperand(0).getReg();
4123     Data.N3 = getDefIgnoringCopies(Data.N3, *MRI)->getOperand(0).getReg();
4124   }
4125 
4126   return Data;
4127 }
4128 
4129 /// Return if the addr64 mubuf mode should be used for the given address.
4130 bool AMDGPUInstructionSelector::shouldUseAddr64(MUBUFAddressData Addr) const {
4131   // (ptr_add N2, N3) -> addr64, or
4132   // (ptr_add (ptr_add N2, N3), C1) -> addr64
4133   if (Addr.N2)
4134     return true;
4135 
4136   const RegisterBank *N0Bank = RBI.getRegBank(Addr.N0, *MRI, TRI);
4137   return N0Bank->getID() == AMDGPU::VGPRRegBankID;
4138 }
4139 
4140 /// Split an immediate offset \p ImmOffset depending on whether it fits in the
4141 /// immediate field. Modifies \p ImmOffset and sets \p SOffset to the variable
4142 /// component.
4143 void AMDGPUInstructionSelector::splitIllegalMUBUFOffset(
4144   MachineIRBuilder &B, Register &SOffset, int64_t &ImmOffset) const {
4145   if (SIInstrInfo::isLegalMUBUFImmOffset(ImmOffset))
4146     return;
4147 
4148   // Illegal offset, store it in soffset.
4149   SOffset = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
4150   B.buildInstr(AMDGPU::S_MOV_B32)
4151     .addDef(SOffset)
4152     .addImm(ImmOffset);
4153   ImmOffset = 0;
4154 }
4155 
4156 bool AMDGPUInstructionSelector::selectMUBUFAddr64Impl(
4157   MachineOperand &Root, Register &VAddr, Register &RSrcReg,
4158   Register &SOffset, int64_t &Offset) const {
4159   // FIXME: Predicates should stop this from reaching here.
4160   // addr64 bit was removed for volcanic islands.
4161   if (!STI.hasAddr64() || STI.useFlatForGlobal())
4162     return false;
4163 
4164   MUBUFAddressData AddrData = parseMUBUFAddress(Root.getReg());
4165   if (!shouldUseAddr64(AddrData))
4166     return false;
4167 
4168   Register N0 = AddrData.N0;
4169   Register N2 = AddrData.N2;
4170   Register N3 = AddrData.N3;
4171   Offset = AddrData.Offset;
4172 
4173   // Base pointer for the SRD.
4174   Register SRDPtr;
4175 
4176   if (N2) {
4177     if (RBI.getRegBank(N2, *MRI, TRI)->getID() == AMDGPU::VGPRRegBankID) {
4178       assert(N3);
4179       if (RBI.getRegBank(N3, *MRI, TRI)->getID() == AMDGPU::VGPRRegBankID) {
4180         // Both N2 and N3 are divergent. Use N0 (the result of the add) as the
4181         // addr64, and construct the default resource from a 0 address.
4182         VAddr = N0;
4183       } else {
4184         SRDPtr = N3;
4185         VAddr = N2;
4186       }
4187     } else {
4188       // N2 is not divergent.
4189       SRDPtr = N2;
4190       VAddr = N3;
4191     }
4192   } else if (RBI.getRegBank(N0, *MRI, TRI)->getID() == AMDGPU::VGPRRegBankID) {
4193     // Use the default null pointer in the resource
4194     VAddr = N0;
4195   } else {
4196     // N0 -> offset, or
4197     // (N0 + C1) -> offset
4198     SRDPtr = N0;
4199   }
4200 
4201   MachineIRBuilder B(*Root.getParent());
4202   RSrcReg = buildAddr64RSrc(B, *MRI, TII, SRDPtr);
4203   splitIllegalMUBUFOffset(B, SOffset, Offset);
4204   return true;
4205 }
4206 
4207 bool AMDGPUInstructionSelector::selectMUBUFOffsetImpl(
4208   MachineOperand &Root, Register &RSrcReg, Register &SOffset,
4209   int64_t &Offset) const {
4210 
4211   // FIXME: Pattern should not reach here.
4212   if (STI.useFlatForGlobal())
4213     return false;
4214 
4215   MUBUFAddressData AddrData = parseMUBUFAddress(Root.getReg());
4216   if (shouldUseAddr64(AddrData))
4217     return false;
4218 
4219   // N0 -> offset, or
4220   // (N0 + C1) -> offset
4221   Register SRDPtr = AddrData.N0;
4222   Offset = AddrData.Offset;
4223 
4224   // TODO: Look through extensions for 32-bit soffset.
4225   MachineIRBuilder B(*Root.getParent());
4226 
4227   RSrcReg = buildOffsetSrc(B, *MRI, TII, SRDPtr);
4228   splitIllegalMUBUFOffset(B, SOffset, Offset);
4229   return true;
4230 }
4231 
4232 InstructionSelector::ComplexRendererFns
4233 AMDGPUInstructionSelector::selectMUBUFAddr64(MachineOperand &Root) const {
4234   Register VAddr;
4235   Register RSrcReg;
4236   Register SOffset;
4237   int64_t Offset = 0;
4238 
4239   if (!selectMUBUFAddr64Impl(Root, VAddr, RSrcReg, SOffset, Offset))
4240     return {};
4241 
4242   // FIXME: Use defaulted operands for trailing 0s and remove from the complex
4243   // pattern.
4244   return {{
4245       [=](MachineInstrBuilder &MIB) {  // rsrc
4246         MIB.addReg(RSrcReg);
4247       },
4248       [=](MachineInstrBuilder &MIB) { // vaddr
4249         MIB.addReg(VAddr);
4250       },
4251       [=](MachineInstrBuilder &MIB) { // soffset
4252         if (SOffset)
4253           MIB.addReg(SOffset);
4254         else
4255           MIB.addImm(0);
4256       },
4257       [=](MachineInstrBuilder &MIB) { // offset
4258         MIB.addImm(Offset);
4259       },
4260       addZeroImm, //  cpol
4261       addZeroImm, //  tfe
4262       addZeroImm  //  swz
4263     }};
4264 }
4265 
4266 InstructionSelector::ComplexRendererFns
4267 AMDGPUInstructionSelector::selectMUBUFOffset(MachineOperand &Root) const {
4268   Register RSrcReg;
4269   Register SOffset;
4270   int64_t Offset = 0;
4271 
4272   if (!selectMUBUFOffsetImpl(Root, RSrcReg, SOffset, Offset))
4273     return {};
4274 
4275   return {{
4276       [=](MachineInstrBuilder &MIB) {  // rsrc
4277         MIB.addReg(RSrcReg);
4278       },
4279       [=](MachineInstrBuilder &MIB) { // soffset
4280         if (SOffset)
4281           MIB.addReg(SOffset);
4282         else
4283           MIB.addImm(0);
4284       },
4285       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); }, // offset
4286       addZeroImm, //  cpol
4287       addZeroImm, //  tfe
4288       addZeroImm, //  swz
4289     }};
4290 }
4291 
4292 InstructionSelector::ComplexRendererFns
4293 AMDGPUInstructionSelector::selectMUBUFAddr64Atomic(MachineOperand &Root) const {
4294   Register VAddr;
4295   Register RSrcReg;
4296   Register SOffset;
4297   int64_t Offset = 0;
4298 
4299   if (!selectMUBUFAddr64Impl(Root, VAddr, RSrcReg, SOffset, Offset))
4300     return {};
4301 
4302   // FIXME: Use defaulted operands for trailing 0s and remove from the complex
4303   // pattern.
4304   return {{
4305       [=](MachineInstrBuilder &MIB) {  // rsrc
4306         MIB.addReg(RSrcReg);
4307       },
4308       [=](MachineInstrBuilder &MIB) { // vaddr
4309         MIB.addReg(VAddr);
4310       },
4311       [=](MachineInstrBuilder &MIB) { // soffset
4312         if (SOffset)
4313           MIB.addReg(SOffset);
4314         else
4315           MIB.addImm(0);
4316       },
4317       [=](MachineInstrBuilder &MIB) { // offset
4318         MIB.addImm(Offset);
4319       },
4320       [=](MachineInstrBuilder &MIB) {
4321         MIB.addImm(AMDGPU::CPol::GLC); // cpol
4322       }
4323     }};
4324 }
4325 
4326 InstructionSelector::ComplexRendererFns
4327 AMDGPUInstructionSelector::selectMUBUFOffsetAtomic(MachineOperand &Root) const {
4328   Register RSrcReg;
4329   Register SOffset;
4330   int64_t Offset = 0;
4331 
4332   if (!selectMUBUFOffsetImpl(Root, RSrcReg, SOffset, Offset))
4333     return {};
4334 
4335   return {{
4336       [=](MachineInstrBuilder &MIB) {  // rsrc
4337         MIB.addReg(RSrcReg);
4338       },
4339       [=](MachineInstrBuilder &MIB) { // soffset
4340         if (SOffset)
4341           MIB.addReg(SOffset);
4342         else
4343           MIB.addImm(0);
4344       },
4345       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); }, // offset
4346       [=](MachineInstrBuilder &MIB) { MIB.addImm(AMDGPU::CPol::GLC); } // cpol
4347     }};
4348 }
4349 
4350 /// Get an immediate that must be 32-bits, and treated as zero extended.
4351 static Optional<uint64_t> getConstantZext32Val(Register Reg,
4352                                                const MachineRegisterInfo &MRI) {
4353   // getIConstantVRegVal sexts any values, so see if that matters.
4354   Optional<int64_t> OffsetVal = getIConstantVRegSExtVal(Reg, MRI);
4355   if (!OffsetVal || !isInt<32>(*OffsetVal))
4356     return None;
4357   return Lo_32(*OffsetVal);
4358 }
4359 
4360 InstructionSelector::ComplexRendererFns
4361 AMDGPUInstructionSelector::selectSMRDBufferImm(MachineOperand &Root) const {
4362   Optional<uint64_t> OffsetVal = getConstantZext32Val(Root.getReg(), *MRI);
4363   if (!OffsetVal)
4364     return {};
4365 
4366   Optional<int64_t> EncodedImm =
4367       AMDGPU::getSMRDEncodedOffset(STI, *OffsetVal, true);
4368   if (!EncodedImm)
4369     return {};
4370 
4371   return {{ [=](MachineInstrBuilder &MIB) { MIB.addImm(*EncodedImm); }  }};
4372 }
4373 
4374 InstructionSelector::ComplexRendererFns
4375 AMDGPUInstructionSelector::selectSMRDBufferImm32(MachineOperand &Root) const {
4376   assert(STI.getGeneration() == AMDGPUSubtarget::SEA_ISLANDS);
4377 
4378   Optional<uint64_t> OffsetVal = getConstantZext32Val(Root.getReg(), *MRI);
4379   if (!OffsetVal)
4380     return {};
4381 
4382   Optional<int64_t> EncodedImm
4383     = AMDGPU::getSMRDEncodedLiteralOffset32(STI, *OffsetVal);
4384   if (!EncodedImm)
4385     return {};
4386 
4387   return {{ [=](MachineInstrBuilder &MIB) { MIB.addImm(*EncodedImm); }  }};
4388 }
4389 
4390 void AMDGPUInstructionSelector::renderTruncImm32(MachineInstrBuilder &MIB,
4391                                                  const MachineInstr &MI,
4392                                                  int OpIdx) const {
4393   assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
4394          "Expected G_CONSTANT");
4395   MIB.addImm(MI.getOperand(1).getCImm()->getSExtValue());
4396 }
4397 
4398 void AMDGPUInstructionSelector::renderNegateImm(MachineInstrBuilder &MIB,
4399                                                 const MachineInstr &MI,
4400                                                 int OpIdx) const {
4401   assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
4402          "Expected G_CONSTANT");
4403   MIB.addImm(-MI.getOperand(1).getCImm()->getSExtValue());
4404 }
4405 
4406 void AMDGPUInstructionSelector::renderBitcastImm(MachineInstrBuilder &MIB,
4407                                                  const MachineInstr &MI,
4408                                                  int OpIdx) const {
4409   assert(OpIdx == -1);
4410 
4411   const MachineOperand &Op = MI.getOperand(1);
4412   if (MI.getOpcode() == TargetOpcode::G_FCONSTANT)
4413     MIB.addImm(Op.getFPImm()->getValueAPF().bitcastToAPInt().getZExtValue());
4414   else {
4415     assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && "Expected G_CONSTANT");
4416     MIB.addImm(Op.getCImm()->getSExtValue());
4417   }
4418 }
4419 
4420 void AMDGPUInstructionSelector::renderPopcntImm(MachineInstrBuilder &MIB,
4421                                                 const MachineInstr &MI,
4422                                                 int OpIdx) const {
4423   assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
4424          "Expected G_CONSTANT");
4425   MIB.addImm(MI.getOperand(1).getCImm()->getValue().countPopulation());
4426 }
4427 
4428 /// This only really exists to satisfy DAG type checking machinery, so is a
4429 /// no-op here.
4430 void AMDGPUInstructionSelector::renderTruncTImm(MachineInstrBuilder &MIB,
4431                                                 const MachineInstr &MI,
4432                                                 int OpIdx) const {
4433   MIB.addImm(MI.getOperand(OpIdx).getImm());
4434 }
4435 
4436 void AMDGPUInstructionSelector::renderExtractCPol(MachineInstrBuilder &MIB,
4437                                                   const MachineInstr &MI,
4438                                                   int OpIdx) const {
4439   assert(OpIdx >= 0 && "expected to match an immediate operand");
4440   MIB.addImm(MI.getOperand(OpIdx).getImm() & AMDGPU::CPol::ALL);
4441 }
4442 
4443 void AMDGPUInstructionSelector::renderExtractSWZ(MachineInstrBuilder &MIB,
4444                                                  const MachineInstr &MI,
4445                                                  int OpIdx) const {
4446   assert(OpIdx >= 0 && "expected to match an immediate operand");
4447   MIB.addImm((MI.getOperand(OpIdx).getImm() >> 3) & 1);
4448 }
4449 
4450 void AMDGPUInstructionSelector::renderSetGLC(MachineInstrBuilder &MIB,
4451                                              const MachineInstr &MI,
4452                                              int OpIdx) const {
4453   assert(OpIdx >= 0 && "expected to match an immediate operand");
4454   MIB.addImm(MI.getOperand(OpIdx).getImm() | AMDGPU::CPol::GLC);
4455 }
4456 
4457 void AMDGPUInstructionSelector::renderFrameIndex(MachineInstrBuilder &MIB,
4458                                                  const MachineInstr &MI,
4459                                                  int OpIdx) const {
4460   MIB.addFrameIndex((MI.getOperand(1).getIndex()));
4461 }
4462 
4463 bool AMDGPUInstructionSelector::isInlineImmediate16(int64_t Imm) const {
4464   return AMDGPU::isInlinableLiteral16(Imm, STI.hasInv2PiInlineImm());
4465 }
4466 
4467 bool AMDGPUInstructionSelector::isInlineImmediate32(int64_t Imm) const {
4468   return AMDGPU::isInlinableLiteral32(Imm, STI.hasInv2PiInlineImm());
4469 }
4470 
4471 bool AMDGPUInstructionSelector::isInlineImmediate64(int64_t Imm) const {
4472   return AMDGPU::isInlinableLiteral64(Imm, STI.hasInv2PiInlineImm());
4473 }
4474 
4475 bool AMDGPUInstructionSelector::isInlineImmediate(const APFloat &Imm) const {
4476   return TII.isInlineConstant(Imm);
4477 }
4478