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 "AMDGPUInstrInfo.h"
16 #include "AMDGPUGlobalISelUtils.h"
17 #include "AMDGPURegisterBankInfo.h"
18 #include "AMDGPURegisterInfo.h"
19 #include "AMDGPUSubtarget.h"
20 #include "AMDGPUTargetMachine.h"
21 #include "MCTargetDesc/AMDGPUMCTargetDesc.h"
22 #include "SIMachineFunctionInfo.h"
23 #include "llvm/CodeGen/GlobalISel/GISelKnownBits.h"
24 #include "llvm/CodeGen/GlobalISel/InstructionSelector.h"
25 #include "llvm/CodeGen/GlobalISel/InstructionSelectorImpl.h"
26 #include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
27 #include "llvm/CodeGen/GlobalISel/MIPatternMatch.h"
28 #include "llvm/CodeGen/GlobalISel/Utils.h"
29 #include "llvm/CodeGen/MachineBasicBlock.h"
30 #include "llvm/CodeGen/MachineFunction.h"
31 #include "llvm/CodeGen/MachineInstr.h"
32 #include "llvm/CodeGen/MachineInstrBuilder.h"
33 #include "llvm/CodeGen/MachineRegisterInfo.h"
34 #include "llvm/IR/Type.h"
35 #include "llvm/Support/Debug.h"
36 #include "llvm/Support/raw_ostream.h"
37 
38 #define DEBUG_TYPE "amdgpu-isel"
39 
40 using namespace llvm;
41 using namespace MIPatternMatch;
42 
43 #define GET_GLOBALISEL_IMPL
44 #define AMDGPUSubtarget GCNSubtarget
45 #include "AMDGPUGenGlobalISel.inc"
46 #undef GET_GLOBALISEL_IMPL
47 #undef AMDGPUSubtarget
48 
49 AMDGPUInstructionSelector::AMDGPUInstructionSelector(
50     const GCNSubtarget &STI, const AMDGPURegisterBankInfo &RBI,
51     const AMDGPUTargetMachine &TM)
52     : InstructionSelector(), TII(*STI.getInstrInfo()),
53       TRI(*STI.getRegisterInfo()), RBI(RBI), TM(TM),
54       STI(STI),
55       EnableLateStructurizeCFG(AMDGPUTargetMachine::EnableLateStructurizeCFG),
56 #define GET_GLOBALISEL_PREDICATES_INIT
57 #include "AMDGPUGenGlobalISel.inc"
58 #undef GET_GLOBALISEL_PREDICATES_INIT
59 #define GET_GLOBALISEL_TEMPORARIES_INIT
60 #include "AMDGPUGenGlobalISel.inc"
61 #undef GET_GLOBALISEL_TEMPORARIES_INIT
62 {
63 }
64 
65 const char *AMDGPUInstructionSelector::getName() { return DEBUG_TYPE; }
66 
67 void AMDGPUInstructionSelector::setupMF(MachineFunction &MF, GISelKnownBits &KB,
68                                         CodeGenCoverage &CoverageInfo) {
69   MRI = &MF.getRegInfo();
70   InstructionSelector::setupMF(MF, KB, CoverageInfo);
71 }
72 
73 bool AMDGPUInstructionSelector::isVCC(Register Reg,
74                                       const MachineRegisterInfo &MRI) const {
75   if (Register::isPhysicalRegister(Reg))
76     return Reg == TRI.getVCC();
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       Register MaskedReg = MRI->createVirtualRegister(SrcRC);
143 
144       // We can't trust the high bits at this point, so clear them.
145 
146       // TODO: Skip masking high bits if def is known boolean.
147 
148       unsigned AndOpc = TRI.isSGPRClass(SrcRC) ?
149         AMDGPU::S_AND_B32 : AMDGPU::V_AND_B32_e32;
150       BuildMI(*BB, &I, DL, TII.get(AndOpc), MaskedReg)
151         .addImm(1)
152         .addReg(SrcReg);
153       BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_CMP_NE_U32_e64), DstReg)
154         .addImm(0)
155         .addReg(MaskedReg);
156 
157       if (!MRI->getRegClassOrNull(SrcReg))
158         MRI->setRegClass(SrcReg, SrcRC);
159       I.eraseFromParent();
160       return true;
161     }
162 
163     const TargetRegisterClass *RC =
164       TRI.getConstrainedRegClassForOperand(Dst, *MRI);
165     if (RC && !RBI.constrainGenericRegister(DstReg, *RC, *MRI))
166       return false;
167 
168     // Don't constrain the source register to a class so the def instruction
169     // handles it (unless it's undef).
170     //
171     // FIXME: This is a hack. When selecting the def, we neeed to know
172     // specifically know that the result is VCCRegBank, and not just an SGPR
173     // with size 1. An SReg_32 with size 1 is ambiguous with wave32.
174     if (Src.isUndef()) {
175       const TargetRegisterClass *SrcRC =
176         TRI.getConstrainedRegClassForOperand(Src, *MRI);
177       if (SrcRC && !RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI))
178         return false;
179     }
180 
181     return true;
182   }
183 
184   for (const MachineOperand &MO : I.operands()) {
185     if (Register::isPhysicalRegister(MO.getReg()))
186       continue;
187 
188     const TargetRegisterClass *RC =
189             TRI.getConstrainedRegClassForOperand(MO, *MRI);
190     if (!RC)
191       continue;
192     RBI.constrainGenericRegister(MO.getReg(), *RC, *MRI);
193   }
194   return true;
195 }
196 
197 bool AMDGPUInstructionSelector::selectPHI(MachineInstr &I) const {
198   const Register DefReg = I.getOperand(0).getReg();
199   const LLT DefTy = MRI->getType(DefReg);
200 
201   // TODO: Verify this doesn't have insane operands (i.e. VGPR to SGPR copy)
202 
203   const RegClassOrRegBank &RegClassOrBank =
204     MRI->getRegClassOrRegBank(DefReg);
205 
206   const TargetRegisterClass *DefRC
207     = RegClassOrBank.dyn_cast<const TargetRegisterClass *>();
208   if (!DefRC) {
209     if (!DefTy.isValid()) {
210       LLVM_DEBUG(dbgs() << "PHI operand has no type, not a gvreg?\n");
211       return false;
212     }
213 
214     const RegisterBank &RB = *RegClassOrBank.get<const RegisterBank *>();
215     DefRC = TRI.getRegClassForTypeOnBank(DefTy, RB, *MRI);
216     if (!DefRC) {
217       LLVM_DEBUG(dbgs() << "PHI operand has unexpected size/bank\n");
218       return false;
219     }
220   }
221 
222   // TODO: Verify that all registers have the same bank
223   I.setDesc(TII.get(TargetOpcode::PHI));
224   return RBI.constrainGenericRegister(DefReg, *DefRC, *MRI);
225 }
226 
227 MachineOperand
228 AMDGPUInstructionSelector::getSubOperand64(MachineOperand &MO,
229                                            const TargetRegisterClass &SubRC,
230                                            unsigned SubIdx) const {
231 
232   MachineInstr *MI = MO.getParent();
233   MachineBasicBlock *BB = MO.getParent()->getParent();
234   Register DstReg = MRI->createVirtualRegister(&SubRC);
235 
236   if (MO.isReg()) {
237     unsigned ComposedSubIdx = TRI.composeSubRegIndices(MO.getSubReg(), SubIdx);
238     Register Reg = MO.getReg();
239     BuildMI(*BB, MI, MI->getDebugLoc(), TII.get(AMDGPU::COPY), DstReg)
240             .addReg(Reg, 0, ComposedSubIdx);
241 
242     return MachineOperand::CreateReg(DstReg, MO.isDef(), MO.isImplicit(),
243                                      MO.isKill(), MO.isDead(), MO.isUndef(),
244                                      MO.isEarlyClobber(), 0, MO.isDebug(),
245                                      MO.isInternalRead());
246   }
247 
248   assert(MO.isImm());
249 
250   APInt Imm(64, MO.getImm());
251 
252   switch (SubIdx) {
253   default:
254     llvm_unreachable("do not know to split immediate with this sub index.");
255   case AMDGPU::sub0:
256     return MachineOperand::CreateImm(Imm.getLoBits(32).getSExtValue());
257   case AMDGPU::sub1:
258     return MachineOperand::CreateImm(Imm.getHiBits(32).getSExtValue());
259   }
260 }
261 
262 static unsigned getLogicalBitOpcode(unsigned Opc, bool Is64) {
263   switch (Opc) {
264   case AMDGPU::G_AND:
265     return Is64 ? AMDGPU::S_AND_B64 : AMDGPU::S_AND_B32;
266   case AMDGPU::G_OR:
267     return Is64 ? AMDGPU::S_OR_B64 : AMDGPU::S_OR_B32;
268   case AMDGPU::G_XOR:
269     return Is64 ? AMDGPU::S_XOR_B64 : AMDGPU::S_XOR_B32;
270   default:
271     llvm_unreachable("not a bit op");
272   }
273 }
274 
275 bool AMDGPUInstructionSelector::selectG_AND_OR_XOR(MachineInstr &I) const {
276   MachineOperand &Dst = I.getOperand(0);
277   MachineOperand &Src0 = I.getOperand(1);
278   MachineOperand &Src1 = I.getOperand(2);
279   Register DstReg = Dst.getReg();
280   unsigned Size = RBI.getSizeInBits(DstReg, *MRI, TRI);
281 
282   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
283   if (DstRB->getID() == AMDGPU::VCCRegBankID) {
284     const TargetRegisterClass *RC = TRI.getBoolRC();
285     unsigned InstOpc = getLogicalBitOpcode(I.getOpcode(),
286                                            RC == &AMDGPU::SReg_64RegClass);
287     I.setDesc(TII.get(InstOpc));
288 
289     // FIXME: Hack to avoid turning the register bank into a register class.
290     // The selector for G_ICMP relies on seeing the register bank for the result
291     // is VCC. In wave32 if we constrain the registers to SReg_32 here, it will
292     // be ambiguous whether it's a scalar or vector bool.
293     if (Src0.isUndef() && !MRI->getRegClassOrNull(Src0.getReg()))
294       MRI->setRegClass(Src0.getReg(), RC);
295     if (Src1.isUndef() && !MRI->getRegClassOrNull(Src1.getReg()))
296       MRI->setRegClass(Src1.getReg(), RC);
297 
298     return RBI.constrainGenericRegister(DstReg, *RC, *MRI);
299   }
300 
301   // TODO: Should this allow an SCC bank result, and produce a copy from SCC for
302   // the result?
303   if (DstRB->getID() == AMDGPU::SGPRRegBankID) {
304     unsigned InstOpc = getLogicalBitOpcode(I.getOpcode(), Size > 32);
305     I.setDesc(TII.get(InstOpc));
306     // Dead implicit-def of scc
307     I.addOperand(MachineOperand::CreateReg(AMDGPU::SCC, true, // isDef
308                                            true, // isImp
309                                            false, // isKill
310                                            true)); // isDead
311     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
312   }
313 
314   return false;
315 }
316 
317 bool AMDGPUInstructionSelector::selectG_ADD_SUB(MachineInstr &I) const {
318   MachineBasicBlock *BB = I.getParent();
319   MachineFunction *MF = BB->getParent();
320   Register DstReg = I.getOperand(0).getReg();
321   const DebugLoc &DL = I.getDebugLoc();
322   unsigned Size = RBI.getSizeInBits(DstReg, *MRI, TRI);
323   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
324   const bool IsSALU = DstRB->getID() == AMDGPU::SGPRRegBankID;
325   const bool Sub = I.getOpcode() == TargetOpcode::G_SUB;
326 
327   if (Size == 32) {
328     if (IsSALU) {
329       const unsigned Opc = Sub ? AMDGPU::S_SUB_U32 : AMDGPU::S_ADD_U32;
330       MachineInstr *Add =
331         BuildMI(*BB, &I, DL, TII.get(Opc), DstReg)
332         .add(I.getOperand(1))
333         .add(I.getOperand(2));
334       I.eraseFromParent();
335       return constrainSelectedInstRegOperands(*Add, TII, TRI, RBI);
336     }
337 
338     if (STI.hasAddNoCarry()) {
339       const unsigned Opc = Sub ? AMDGPU::V_SUB_U32_e64 : AMDGPU::V_ADD_U32_e64;
340       I.setDesc(TII.get(Opc));
341       I.addOperand(*MF, MachineOperand::CreateImm(0));
342       I.addOperand(*MF, MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
343       return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
344     }
345 
346     const unsigned Opc = Sub ? AMDGPU::V_SUB_I32_e64 : AMDGPU::V_ADD_I32_e64;
347 
348     Register UnusedCarry = MRI->createVirtualRegister(TRI.getWaveMaskRegClass());
349     MachineInstr *Add
350       = BuildMI(*BB, &I, DL, TII.get(Opc), DstReg)
351       .addDef(UnusedCarry, RegState::Dead)
352       .add(I.getOperand(1))
353       .add(I.getOperand(2))
354       .addImm(0);
355     I.eraseFromParent();
356     return constrainSelectedInstRegOperands(*Add, TII, TRI, RBI);
357   }
358 
359   assert(!Sub && "illegal sub should not reach here");
360 
361   const TargetRegisterClass &RC
362     = IsSALU ? AMDGPU::SReg_64_XEXECRegClass : AMDGPU::VReg_64RegClass;
363   const TargetRegisterClass &HalfRC
364     = IsSALU ? AMDGPU::SReg_32RegClass : AMDGPU::VGPR_32RegClass;
365 
366   MachineOperand Lo1(getSubOperand64(I.getOperand(1), HalfRC, AMDGPU::sub0));
367   MachineOperand Lo2(getSubOperand64(I.getOperand(2), HalfRC, AMDGPU::sub0));
368   MachineOperand Hi1(getSubOperand64(I.getOperand(1), HalfRC, AMDGPU::sub1));
369   MachineOperand Hi2(getSubOperand64(I.getOperand(2), HalfRC, AMDGPU::sub1));
370 
371   Register DstLo = MRI->createVirtualRegister(&HalfRC);
372   Register DstHi = MRI->createVirtualRegister(&HalfRC);
373 
374   if (IsSALU) {
375     BuildMI(*BB, &I, DL, TII.get(AMDGPU::S_ADD_U32), DstLo)
376       .add(Lo1)
377       .add(Lo2);
378     BuildMI(*BB, &I, DL, TII.get(AMDGPU::S_ADDC_U32), DstHi)
379       .add(Hi1)
380       .add(Hi2);
381   } else {
382     const TargetRegisterClass *CarryRC = TRI.getWaveMaskRegClass();
383     Register CarryReg = MRI->createVirtualRegister(CarryRC);
384     BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_ADD_I32_e64), DstLo)
385       .addDef(CarryReg)
386       .add(Lo1)
387       .add(Lo2)
388       .addImm(0);
389     MachineInstr *Addc = BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_ADDC_U32_e64), DstHi)
390       .addDef(MRI->createVirtualRegister(CarryRC), RegState::Dead)
391       .add(Hi1)
392       .add(Hi2)
393       .addReg(CarryReg, RegState::Kill)
394       .addImm(0);
395 
396     if (!constrainSelectedInstRegOperands(*Addc, TII, TRI, RBI))
397       return false;
398   }
399 
400   BuildMI(*BB, &I, DL, TII.get(AMDGPU::REG_SEQUENCE), DstReg)
401     .addReg(DstLo)
402     .addImm(AMDGPU::sub0)
403     .addReg(DstHi)
404     .addImm(AMDGPU::sub1);
405 
406 
407   if (!RBI.constrainGenericRegister(DstReg, RC, *MRI))
408     return false;
409 
410   I.eraseFromParent();
411   return true;
412 }
413 
414 bool AMDGPUInstructionSelector::selectG_UADDO_USUBO_UADDE_USUBE(
415   MachineInstr &I) const {
416   MachineBasicBlock *BB = I.getParent();
417   MachineFunction *MF = BB->getParent();
418   const DebugLoc &DL = I.getDebugLoc();
419   Register Dst0Reg = I.getOperand(0).getReg();
420   Register Dst1Reg = I.getOperand(1).getReg();
421   const bool IsAdd = I.getOpcode() == AMDGPU::G_UADDO ||
422                      I.getOpcode() == AMDGPU::G_UADDE;
423   const bool HasCarryIn = I.getOpcode() == AMDGPU::G_UADDE ||
424                           I.getOpcode() == AMDGPU::G_USUBE;
425 
426   if (isVCC(Dst1Reg, *MRI)) {
427       // The name of the opcodes are misleading. v_add_i32/v_sub_i32 have unsigned
428       // carry out despite the _i32 name. These were renamed in VI to _U32.
429       // FIXME: We should probably rename the opcodes here.
430     unsigned NoCarryOpc = IsAdd ? AMDGPU::V_ADD_I32_e64 : AMDGPU::V_SUB_I32_e64;
431     unsigned CarryOpc = IsAdd ? AMDGPU::V_ADDC_U32_e64 : AMDGPU::V_SUBB_U32_e64;
432     I.setDesc(TII.get(HasCarryIn ? CarryOpc : NoCarryOpc));
433     I.addOperand(*MF, MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
434     I.addOperand(*MF, MachineOperand::CreateImm(0));
435     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
436   }
437 
438   Register Src0Reg = I.getOperand(2).getReg();
439   Register Src1Reg = I.getOperand(3).getReg();
440 
441   if (HasCarryIn) {
442     BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), AMDGPU::SCC)
443       .addReg(I.getOperand(4).getReg());
444   }
445 
446   unsigned NoCarryOpc = IsAdd ? AMDGPU::S_ADD_U32 : AMDGPU::S_SUB_U32;
447   unsigned CarryOpc = IsAdd ? AMDGPU::S_ADDC_U32 : AMDGPU::S_SUBB_U32;
448 
449   BuildMI(*BB, &I, DL, TII.get(HasCarryIn ? CarryOpc : NoCarryOpc), Dst0Reg)
450     .add(I.getOperand(2))
451     .add(I.getOperand(3));
452   BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), Dst1Reg)
453     .addReg(AMDGPU::SCC);
454 
455   if (!MRI->getRegClassOrNull(Dst1Reg))
456     MRI->setRegClass(Dst1Reg, &AMDGPU::SReg_32RegClass);
457 
458   if (!RBI.constrainGenericRegister(Dst0Reg, AMDGPU::SReg_32RegClass, *MRI) ||
459       !RBI.constrainGenericRegister(Src0Reg, AMDGPU::SReg_32RegClass, *MRI) ||
460       !RBI.constrainGenericRegister(Src1Reg, AMDGPU::SReg_32RegClass, *MRI))
461     return false;
462 
463   if (HasCarryIn &&
464       !RBI.constrainGenericRegister(I.getOperand(4).getReg(),
465                                     AMDGPU::SReg_32RegClass, *MRI))
466     return false;
467 
468   I.eraseFromParent();
469   return true;
470 }
471 
472 bool AMDGPUInstructionSelector::selectG_EXTRACT(MachineInstr &I) const {
473   MachineBasicBlock *BB = I.getParent();
474   Register DstReg = I.getOperand(0).getReg();
475   Register SrcReg = I.getOperand(1).getReg();
476   LLT DstTy = MRI->getType(DstReg);
477   LLT SrcTy = MRI->getType(SrcReg);
478   const unsigned SrcSize = SrcTy.getSizeInBits();
479   const unsigned DstSize = DstTy.getSizeInBits();
480 
481   // TODO: Should handle any multiple of 32 offset.
482   unsigned Offset = I.getOperand(2).getImm();
483   if (Offset % DstSize != 0)
484     return false;
485 
486   const RegisterBank *SrcBank = RBI.getRegBank(SrcReg, *MRI, TRI);
487   const TargetRegisterClass *SrcRC =
488     TRI.getRegClassForSizeOnBank(SrcSize, *SrcBank, *MRI);
489   if (!SrcRC)
490     return false;
491 
492   ArrayRef<int16_t> SubRegs = TRI.getRegSplitParts(SrcRC, DstSize / 8);
493 
494   const DebugLoc &DL = I.getDebugLoc();
495   MachineInstr *Copy = BuildMI(*BB, &I, DL, TII.get(TargetOpcode::COPY), DstReg)
496                                .addReg(SrcReg, 0, SubRegs[Offset / DstSize]);
497 
498   for (const MachineOperand &MO : Copy->operands()) {
499     const TargetRegisterClass *RC =
500             TRI.getConstrainedRegClassForOperand(MO, *MRI);
501     if (!RC)
502       continue;
503     RBI.constrainGenericRegister(MO.getReg(), *RC, *MRI);
504   }
505   I.eraseFromParent();
506   return true;
507 }
508 
509 bool AMDGPUInstructionSelector::selectG_MERGE_VALUES(MachineInstr &MI) const {
510   MachineBasicBlock *BB = MI.getParent();
511   Register DstReg = MI.getOperand(0).getReg();
512   LLT DstTy = MRI->getType(DstReg);
513   LLT SrcTy = MRI->getType(MI.getOperand(1).getReg());
514 
515   const unsigned SrcSize = SrcTy.getSizeInBits();
516   if (SrcSize < 32)
517     return selectImpl(MI, *CoverageInfo);
518 
519   const DebugLoc &DL = MI.getDebugLoc();
520   const RegisterBank *DstBank = RBI.getRegBank(DstReg, *MRI, TRI);
521   const unsigned DstSize = DstTy.getSizeInBits();
522   const TargetRegisterClass *DstRC =
523     TRI.getRegClassForSizeOnBank(DstSize, *DstBank, *MRI);
524   if (!DstRC)
525     return false;
526 
527   ArrayRef<int16_t> SubRegs = TRI.getRegSplitParts(DstRC, SrcSize / 8);
528   MachineInstrBuilder MIB =
529     BuildMI(*BB, &MI, DL, TII.get(TargetOpcode::REG_SEQUENCE), DstReg);
530   for (int I = 0, E = MI.getNumOperands() - 1; I != E; ++I) {
531     MachineOperand &Src = MI.getOperand(I + 1);
532     MIB.addReg(Src.getReg(), getUndefRegState(Src.isUndef()));
533     MIB.addImm(SubRegs[I]);
534 
535     const TargetRegisterClass *SrcRC
536       = TRI.getConstrainedRegClassForOperand(Src, *MRI);
537     if (SrcRC && !RBI.constrainGenericRegister(Src.getReg(), *SrcRC, *MRI))
538       return false;
539   }
540 
541   if (!RBI.constrainGenericRegister(DstReg, *DstRC, *MRI))
542     return false;
543 
544   MI.eraseFromParent();
545   return true;
546 }
547 
548 bool AMDGPUInstructionSelector::selectG_UNMERGE_VALUES(MachineInstr &MI) const {
549   MachineBasicBlock *BB = MI.getParent();
550   const int NumDst = MI.getNumOperands() - 1;
551 
552   MachineOperand &Src = MI.getOperand(NumDst);
553 
554   Register SrcReg = Src.getReg();
555   Register DstReg0 = MI.getOperand(0).getReg();
556   LLT DstTy = MRI->getType(DstReg0);
557   LLT SrcTy = MRI->getType(SrcReg);
558 
559   const unsigned DstSize = DstTy.getSizeInBits();
560   const unsigned SrcSize = SrcTy.getSizeInBits();
561   const DebugLoc &DL = MI.getDebugLoc();
562   const RegisterBank *SrcBank = RBI.getRegBank(SrcReg, *MRI, TRI);
563 
564   const TargetRegisterClass *SrcRC =
565     TRI.getRegClassForSizeOnBank(SrcSize, *SrcBank, *MRI);
566   if (!SrcRC || !RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI))
567     return false;
568 
569   const unsigned SrcFlags = getUndefRegState(Src.isUndef());
570 
571   // Note we could have mixed SGPR and VGPR destination banks for an SGPR
572   // source, and this relies on the fact that the same subregister indices are
573   // used for both.
574   ArrayRef<int16_t> SubRegs = TRI.getRegSplitParts(SrcRC, DstSize / 8);
575   for (int I = 0, E = NumDst; I != E; ++I) {
576     MachineOperand &Dst = MI.getOperand(I);
577     BuildMI(*BB, &MI, DL, TII.get(TargetOpcode::COPY), Dst.getReg())
578       .addReg(SrcReg, SrcFlags, SubRegs[I]);
579 
580     const TargetRegisterClass *DstRC =
581       TRI.getConstrainedRegClassForOperand(Dst, *MRI);
582     if (DstRC && !RBI.constrainGenericRegister(Dst.getReg(), *DstRC, *MRI))
583       return false;
584   }
585 
586   MI.eraseFromParent();
587   return true;
588 }
589 
590 bool AMDGPUInstructionSelector::selectG_PTR_ADD(MachineInstr &I) const {
591   return selectG_ADD_SUB(I);
592 }
593 
594 bool AMDGPUInstructionSelector::selectG_IMPLICIT_DEF(MachineInstr &I) const {
595   const MachineOperand &MO = I.getOperand(0);
596 
597   // FIXME: Interface for getConstrainedRegClassForOperand needs work. The
598   // regbank check here is to know why getConstrainedRegClassForOperand failed.
599   const TargetRegisterClass *RC = TRI.getConstrainedRegClassForOperand(MO, *MRI);
600   if ((!RC && !MRI->getRegBankOrNull(MO.getReg())) ||
601       (RC && RBI.constrainGenericRegister(MO.getReg(), *RC, *MRI))) {
602     I.setDesc(TII.get(TargetOpcode::IMPLICIT_DEF));
603     return true;
604   }
605 
606   return false;
607 }
608 
609 bool AMDGPUInstructionSelector::selectG_INSERT(MachineInstr &I) const {
610   MachineBasicBlock *BB = I.getParent();
611 
612   Register DstReg = I.getOperand(0).getReg();
613   Register Src0Reg = I.getOperand(1).getReg();
614   Register Src1Reg = I.getOperand(2).getReg();
615   LLT Src1Ty = MRI->getType(Src1Reg);
616 
617   unsigned DstSize = MRI->getType(DstReg).getSizeInBits();
618   unsigned InsSize = Src1Ty.getSizeInBits();
619 
620   int64_t Offset = I.getOperand(3).getImm();
621   if (Offset % 32 != 0)
622     return false;
623 
624   unsigned SubReg = TRI.getSubRegFromChannel(Offset / 32, InsSize / 32);
625   if (SubReg == AMDGPU::NoSubRegister)
626     return false;
627 
628   const RegisterBank *DstBank = RBI.getRegBank(DstReg, *MRI, TRI);
629   const TargetRegisterClass *DstRC =
630     TRI.getRegClassForSizeOnBank(DstSize, *DstBank, *MRI);
631   if (!DstRC)
632     return false;
633 
634   const RegisterBank *Src0Bank = RBI.getRegBank(Src0Reg, *MRI, TRI);
635   const RegisterBank *Src1Bank = RBI.getRegBank(Src1Reg, *MRI, TRI);
636   const TargetRegisterClass *Src0RC =
637     TRI.getRegClassForSizeOnBank(DstSize, *Src0Bank, *MRI);
638   const TargetRegisterClass *Src1RC =
639     TRI.getRegClassForSizeOnBank(InsSize, *Src1Bank, *MRI);
640 
641   // Deal with weird cases where the class only partially supports the subreg
642   // index.
643   Src0RC = TRI.getSubClassWithSubReg(Src0RC, SubReg);
644   if (!Src0RC)
645     return false;
646 
647   if (!RBI.constrainGenericRegister(DstReg, *DstRC, *MRI) ||
648       !RBI.constrainGenericRegister(Src0Reg, *Src0RC, *MRI) ||
649       !RBI.constrainGenericRegister(Src1Reg, *Src1RC, *MRI))
650     return false;
651 
652   const DebugLoc &DL = I.getDebugLoc();
653   BuildMI(*BB, &I, DL, TII.get(TargetOpcode::INSERT_SUBREG), DstReg)
654     .addReg(Src0Reg)
655     .addReg(Src1Reg)
656     .addImm(SubReg);
657 
658   I.eraseFromParent();
659   return true;
660 }
661 
662 bool AMDGPUInstructionSelector::selectInterpP1F16(MachineInstr &MI) const {
663   if (STI.getLDSBankCount() != 16)
664     return selectImpl(MI, *CoverageInfo);
665 
666   Register Dst = MI.getOperand(0).getReg();
667   Register Src0 = MI.getOperand(2).getReg();
668   Register M0Val = MI.getOperand(6).getReg();
669   if (!RBI.constrainGenericRegister(M0Val, AMDGPU::SReg_32RegClass, *MRI) ||
670       !RBI.constrainGenericRegister(Dst, AMDGPU::VGPR_32RegClass, *MRI) ||
671       !RBI.constrainGenericRegister(Src0, AMDGPU::VGPR_32RegClass, *MRI))
672     return false;
673 
674   // This requires 2 instructions. It is possible to write a pattern to support
675   // this, but the generated isel emitter doesn't correctly deal with multiple
676   // output instructions using the same physical register input. The copy to m0
677   // is incorrectly placed before the second instruction.
678   //
679   // TODO: Match source modifiers.
680 
681   Register InterpMov = MRI->createVirtualRegister(&AMDGPU::VGPR_32RegClass);
682   const DebugLoc &DL = MI.getDebugLoc();
683   MachineBasicBlock *MBB = MI.getParent();
684 
685   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
686     .addReg(M0Val);
687   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::V_INTERP_MOV_F32), InterpMov)
688     .addImm(2)
689     .addImm(MI.getOperand(4).getImm())  // $attr
690     .addImm(MI.getOperand(3).getImm()); // $attrchan
691 
692   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::V_INTERP_P1LV_F16), Dst)
693     .addImm(0)                          // $src0_modifiers
694     .addReg(Src0)                       // $src0
695     .addImm(MI.getOperand(4).getImm())  // $attr
696     .addImm(MI.getOperand(3).getImm())  // $attrchan
697     .addImm(0)                          // $src2_modifiers
698     .addReg(InterpMov)                  // $src2 - 2 f16 values selected by high
699     .addImm(MI.getOperand(5).getImm())  // $high
700     .addImm(0)                          // $clamp
701     .addImm(0);                         // $omod
702 
703   MI.eraseFromParent();
704   return true;
705 }
706 
707 bool AMDGPUInstructionSelector::selectG_INTRINSIC(MachineInstr &I) const {
708   unsigned IntrinsicID = I.getIntrinsicID();
709   switch (IntrinsicID) {
710   case Intrinsic::amdgcn_if_break: {
711     MachineBasicBlock *BB = I.getParent();
712 
713     // FIXME: Manually selecting to avoid dealiing with the SReg_1 trick
714     // SelectionDAG uses for wave32 vs wave64.
715     BuildMI(*BB, &I, I.getDebugLoc(), TII.get(AMDGPU::SI_IF_BREAK))
716       .add(I.getOperand(0))
717       .add(I.getOperand(2))
718       .add(I.getOperand(3));
719 
720     Register DstReg = I.getOperand(0).getReg();
721     Register Src0Reg = I.getOperand(2).getReg();
722     Register Src1Reg = I.getOperand(3).getReg();
723 
724     I.eraseFromParent();
725 
726     for (Register Reg : { DstReg, Src0Reg, Src1Reg })
727       MRI->setRegClass(Reg, TRI.getWaveMaskRegClass());
728 
729     return true;
730   }
731   case Intrinsic::amdgcn_interp_p1_f16:
732     return selectInterpP1F16(I);
733   case Intrinsic::amdgcn_wqm:
734     return constrainCopyLikeIntrin(I, AMDGPU::WQM);
735   case Intrinsic::amdgcn_softwqm:
736     return constrainCopyLikeIntrin(I, AMDGPU::SOFT_WQM);
737   case Intrinsic::amdgcn_wwm:
738     return constrainCopyLikeIntrin(I, AMDGPU::WWM);
739   default:
740     return selectImpl(I, *CoverageInfo);
741   }
742 }
743 
744 static int getV_CMPOpcode(CmpInst::Predicate P, unsigned Size) {
745   if (Size != 32 && Size != 64)
746     return -1;
747   switch (P) {
748   default:
749     llvm_unreachable("Unknown condition code!");
750   case CmpInst::ICMP_NE:
751     return Size == 32 ? AMDGPU::V_CMP_NE_U32_e64 : AMDGPU::V_CMP_NE_U64_e64;
752   case CmpInst::ICMP_EQ:
753     return Size == 32 ? AMDGPU::V_CMP_EQ_U32_e64 : AMDGPU::V_CMP_EQ_U64_e64;
754   case CmpInst::ICMP_SGT:
755     return Size == 32 ? AMDGPU::V_CMP_GT_I32_e64 : AMDGPU::V_CMP_GT_I64_e64;
756   case CmpInst::ICMP_SGE:
757     return Size == 32 ? AMDGPU::V_CMP_GE_I32_e64 : AMDGPU::V_CMP_GE_I64_e64;
758   case CmpInst::ICMP_SLT:
759     return Size == 32 ? AMDGPU::V_CMP_LT_I32_e64 : AMDGPU::V_CMP_LT_I64_e64;
760   case CmpInst::ICMP_SLE:
761     return Size == 32 ? AMDGPU::V_CMP_LE_I32_e64 : AMDGPU::V_CMP_LE_I64_e64;
762   case CmpInst::ICMP_UGT:
763     return Size == 32 ? AMDGPU::V_CMP_GT_U32_e64 : AMDGPU::V_CMP_GT_U64_e64;
764   case CmpInst::ICMP_UGE:
765     return Size == 32 ? AMDGPU::V_CMP_GE_U32_e64 : AMDGPU::V_CMP_GE_U64_e64;
766   case CmpInst::ICMP_ULT:
767     return Size == 32 ? AMDGPU::V_CMP_LT_U32_e64 : AMDGPU::V_CMP_LT_U64_e64;
768   case CmpInst::ICMP_ULE:
769     return Size == 32 ? AMDGPU::V_CMP_LE_U32_e64 : AMDGPU::V_CMP_LE_U64_e64;
770   }
771 }
772 
773 int AMDGPUInstructionSelector::getS_CMPOpcode(CmpInst::Predicate P,
774                                               unsigned Size) const {
775   if (Size == 64) {
776     if (!STI.hasScalarCompareEq64())
777       return -1;
778 
779     switch (P) {
780     case CmpInst::ICMP_NE:
781       return AMDGPU::S_CMP_LG_U64;
782     case CmpInst::ICMP_EQ:
783       return AMDGPU::S_CMP_EQ_U64;
784     default:
785       return -1;
786     }
787   }
788 
789   if (Size != 32)
790     return -1;
791 
792   switch (P) {
793   case CmpInst::ICMP_NE:
794     return AMDGPU::S_CMP_LG_U32;
795   case CmpInst::ICMP_EQ:
796     return AMDGPU::S_CMP_EQ_U32;
797   case CmpInst::ICMP_SGT:
798     return AMDGPU::S_CMP_GT_I32;
799   case CmpInst::ICMP_SGE:
800     return AMDGPU::S_CMP_GE_I32;
801   case CmpInst::ICMP_SLT:
802     return AMDGPU::S_CMP_LT_I32;
803   case CmpInst::ICMP_SLE:
804     return AMDGPU::S_CMP_LE_I32;
805   case CmpInst::ICMP_UGT:
806     return AMDGPU::S_CMP_GT_U32;
807   case CmpInst::ICMP_UGE:
808     return AMDGPU::S_CMP_GE_U32;
809   case CmpInst::ICMP_ULT:
810     return AMDGPU::S_CMP_LT_U32;
811   case CmpInst::ICMP_ULE:
812     return AMDGPU::S_CMP_LE_U32;
813   default:
814     llvm_unreachable("Unknown condition code!");
815   }
816 }
817 
818 bool AMDGPUInstructionSelector::selectG_ICMP(MachineInstr &I) const {
819   MachineBasicBlock *BB = I.getParent();
820   const DebugLoc &DL = I.getDebugLoc();
821 
822   Register SrcReg = I.getOperand(2).getReg();
823   unsigned Size = RBI.getSizeInBits(SrcReg, *MRI, TRI);
824 
825   auto Pred = (CmpInst::Predicate)I.getOperand(1).getPredicate();
826 
827   Register CCReg = I.getOperand(0).getReg();
828   if (!isVCC(CCReg, *MRI)) {
829     int Opcode = getS_CMPOpcode(Pred, Size);
830     if (Opcode == -1)
831       return false;
832     MachineInstr *ICmp = BuildMI(*BB, &I, DL, TII.get(Opcode))
833             .add(I.getOperand(2))
834             .add(I.getOperand(3));
835     BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), CCReg)
836       .addReg(AMDGPU::SCC);
837     bool Ret =
838         constrainSelectedInstRegOperands(*ICmp, TII, TRI, RBI) &&
839         RBI.constrainGenericRegister(CCReg, AMDGPU::SReg_32RegClass, *MRI);
840     I.eraseFromParent();
841     return Ret;
842   }
843 
844   int Opcode = getV_CMPOpcode(Pred, Size);
845   if (Opcode == -1)
846     return false;
847 
848   MachineInstr *ICmp = BuildMI(*BB, &I, DL, TII.get(Opcode),
849             I.getOperand(0).getReg())
850             .add(I.getOperand(2))
851             .add(I.getOperand(3));
852   RBI.constrainGenericRegister(ICmp->getOperand(0).getReg(),
853                                *TRI.getBoolRC(), *MRI);
854   bool Ret = constrainSelectedInstRegOperands(*ICmp, TII, TRI, RBI);
855   I.eraseFromParent();
856   return Ret;
857 }
858 
859 bool AMDGPUInstructionSelector::selectEndCfIntrinsic(MachineInstr &MI) const {
860   // FIXME: Manually selecting to avoid dealiing with the SReg_1 trick
861   // SelectionDAG uses for wave32 vs wave64.
862   MachineBasicBlock *BB = MI.getParent();
863   BuildMI(*BB, &MI, MI.getDebugLoc(), TII.get(AMDGPU::SI_END_CF))
864       .add(MI.getOperand(1));
865 
866   Register Reg = MI.getOperand(1).getReg();
867   MI.eraseFromParent();
868 
869   if (!MRI->getRegClassOrNull(Reg))
870     MRI->setRegClass(Reg, TRI.getWaveMaskRegClass());
871   return true;
872 }
873 
874 static unsigned getDSShaderTypeValue(const MachineFunction &MF) {
875   switch (MF.getFunction().getCallingConv()) {
876   case CallingConv::AMDGPU_PS:
877     return 1;
878   case CallingConv::AMDGPU_VS:
879     return 2;
880   case CallingConv::AMDGPU_GS:
881     return 3;
882   case CallingConv::AMDGPU_HS:
883   case CallingConv::AMDGPU_LS:
884   case CallingConv::AMDGPU_ES:
885     report_fatal_error("ds_ordered_count unsupported for this calling conv");
886   case CallingConv::AMDGPU_CS:
887   case CallingConv::AMDGPU_KERNEL:
888   case CallingConv::C:
889   case CallingConv::Fast:
890   default:
891     // Assume other calling conventions are various compute callable functions
892     return 0;
893   }
894 }
895 
896 bool AMDGPUInstructionSelector::selectDSOrderedIntrinsic(
897   MachineInstr &MI, Intrinsic::ID IntrID) const {
898   MachineBasicBlock *MBB = MI.getParent();
899   MachineFunction *MF = MBB->getParent();
900   const DebugLoc &DL = MI.getDebugLoc();
901 
902   unsigned IndexOperand = MI.getOperand(7).getImm();
903   bool WaveRelease = MI.getOperand(8).getImm() != 0;
904   bool WaveDone = MI.getOperand(9).getImm() != 0;
905 
906   if (WaveDone && !WaveRelease)
907     report_fatal_error("ds_ordered_count: wave_done requires wave_release");
908 
909   unsigned OrderedCountIndex = IndexOperand & 0x3f;
910   IndexOperand &= ~0x3f;
911   unsigned CountDw = 0;
912 
913   if (STI.getGeneration() >= AMDGPUSubtarget::GFX10) {
914     CountDw = (IndexOperand >> 24) & 0xf;
915     IndexOperand &= ~(0xf << 24);
916 
917     if (CountDw < 1 || CountDw > 4) {
918       report_fatal_error(
919         "ds_ordered_count: dword count must be between 1 and 4");
920     }
921   }
922 
923   if (IndexOperand)
924     report_fatal_error("ds_ordered_count: bad index operand");
925 
926   unsigned Instruction = IntrID == Intrinsic::amdgcn_ds_ordered_add ? 0 : 1;
927   unsigned ShaderType = getDSShaderTypeValue(*MF);
928 
929   unsigned Offset0 = OrderedCountIndex << 2;
930   unsigned Offset1 = WaveRelease | (WaveDone << 1) | (ShaderType << 2) |
931                      (Instruction << 4);
932 
933   if (STI.getGeneration() >= AMDGPUSubtarget::GFX10)
934     Offset1 |= (CountDw - 1) << 6;
935 
936   unsigned Offset = Offset0 | (Offset1 << 8);
937 
938   Register M0Val = MI.getOperand(2).getReg();
939   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
940     .addReg(M0Val);
941 
942   Register DstReg = MI.getOperand(0).getReg();
943   Register ValReg = MI.getOperand(3).getReg();
944   MachineInstrBuilder DS =
945     BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::DS_ORDERED_COUNT), DstReg)
946       .addReg(ValReg)
947       .addImm(Offset)
948       .cloneMemRefs(MI);
949 
950   if (!RBI.constrainGenericRegister(M0Val, AMDGPU::SReg_32RegClass, *MRI))
951     return false;
952 
953   bool Ret = constrainSelectedInstRegOperands(*DS, TII, TRI, RBI);
954   MI.eraseFromParent();
955   return Ret;
956 }
957 
958 static unsigned gwsIntrinToOpcode(unsigned IntrID) {
959   switch (IntrID) {
960   case Intrinsic::amdgcn_ds_gws_init:
961     return AMDGPU::DS_GWS_INIT;
962   case Intrinsic::amdgcn_ds_gws_barrier:
963     return AMDGPU::DS_GWS_BARRIER;
964   case Intrinsic::amdgcn_ds_gws_sema_v:
965     return AMDGPU::DS_GWS_SEMA_V;
966   case Intrinsic::amdgcn_ds_gws_sema_br:
967     return AMDGPU::DS_GWS_SEMA_BR;
968   case Intrinsic::amdgcn_ds_gws_sema_p:
969     return AMDGPU::DS_GWS_SEMA_P;
970   case Intrinsic::amdgcn_ds_gws_sema_release_all:
971     return AMDGPU::DS_GWS_SEMA_RELEASE_ALL;
972   default:
973     llvm_unreachable("not a gws intrinsic");
974   }
975 }
976 
977 bool AMDGPUInstructionSelector::selectDSGWSIntrinsic(MachineInstr &MI,
978                                                      Intrinsic::ID IID) const {
979   if (IID == Intrinsic::amdgcn_ds_gws_sema_release_all &&
980       !STI.hasGWSSemaReleaseAll())
981     return false;
982 
983   // intrinsic ID, vsrc, offset
984   const bool HasVSrc = MI.getNumOperands() == 3;
985   assert(HasVSrc || MI.getNumOperands() == 2);
986 
987   Register BaseOffset = MI.getOperand(HasVSrc ? 2 : 1).getReg();
988   const RegisterBank *OffsetRB = RBI.getRegBank(BaseOffset, *MRI, TRI);
989   if (OffsetRB->getID() != AMDGPU::SGPRRegBankID)
990     return false;
991 
992   MachineInstr *OffsetDef = getDefIgnoringCopies(BaseOffset, *MRI);
993   assert(OffsetDef);
994 
995   unsigned ImmOffset;
996 
997   MachineBasicBlock *MBB = MI.getParent();
998   const DebugLoc &DL = MI.getDebugLoc();
999 
1000   MachineInstr *Readfirstlane = nullptr;
1001 
1002   // If we legalized the VGPR input, strip out the readfirstlane to analyze the
1003   // incoming offset, in case there's an add of a constant. We'll have to put it
1004   // back later.
1005   if (OffsetDef->getOpcode() == AMDGPU::V_READFIRSTLANE_B32) {
1006     Readfirstlane = OffsetDef;
1007     BaseOffset = OffsetDef->getOperand(1).getReg();
1008     OffsetDef = getDefIgnoringCopies(BaseOffset, *MRI);
1009   }
1010 
1011   if (OffsetDef->getOpcode() == AMDGPU::G_CONSTANT) {
1012     // If we have a constant offset, try to use the 0 in m0 as the base.
1013     // TODO: Look into changing the default m0 initialization value. If the
1014     // default -1 only set the low 16-bits, we could leave it as-is and add 1 to
1015     // the immediate offset.
1016 
1017     ImmOffset = OffsetDef->getOperand(1).getCImm()->getZExtValue();
1018     BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::S_MOV_B32), AMDGPU::M0)
1019       .addImm(0);
1020   } else {
1021     std::tie(BaseOffset, ImmOffset, OffsetDef)
1022       = AMDGPU::getBaseWithConstantOffset(*MRI, BaseOffset);
1023 
1024     if (Readfirstlane) {
1025       // We have the constant offset now, so put the readfirstlane back on the
1026       // variable component.
1027       if (!RBI.constrainGenericRegister(BaseOffset, AMDGPU::VGPR_32RegClass, *MRI))
1028         return false;
1029 
1030       Readfirstlane->getOperand(1).setReg(BaseOffset);
1031       BaseOffset = Readfirstlane->getOperand(0).getReg();
1032     } else {
1033       if (!RBI.constrainGenericRegister(BaseOffset,
1034                                         AMDGPU::SReg_32RegClass, *MRI))
1035         return false;
1036     }
1037 
1038     Register M0Base = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1039     BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::S_LSHL_B32), M0Base)
1040       .addReg(BaseOffset)
1041       .addImm(16);
1042 
1043     BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1044       .addReg(M0Base);
1045   }
1046 
1047   // The resource id offset is computed as (<isa opaque base> + M0[21:16] +
1048   // offset field) % 64. Some versions of the programming guide omit the m0
1049   // part, or claim it's from offset 0.
1050   auto MIB = BuildMI(*MBB, &MI, DL, TII.get(gwsIntrinToOpcode(IID)));
1051 
1052   if (HasVSrc) {
1053     Register VSrc = MI.getOperand(1).getReg();
1054     MIB.addReg(VSrc);
1055     if (!RBI.constrainGenericRegister(VSrc, AMDGPU::VGPR_32RegClass, *MRI))
1056       return false;
1057   }
1058 
1059   MIB.addImm(ImmOffset)
1060      .addImm(-1) // $gds
1061      .cloneMemRefs(MI);
1062 
1063   MI.eraseFromParent();
1064   return true;
1065 }
1066 
1067 bool AMDGPUInstructionSelector::selectDSAppendConsume(MachineInstr &MI,
1068                                                       bool IsAppend) const {
1069   Register PtrBase = MI.getOperand(2).getReg();
1070   LLT PtrTy = MRI->getType(PtrBase);
1071   bool IsGDS = PtrTy.getAddressSpace() == AMDGPUAS::REGION_ADDRESS;
1072 
1073   unsigned Offset;
1074   std::tie(PtrBase, Offset) = selectDS1Addr1OffsetImpl(MI.getOperand(2));
1075 
1076   // TODO: Should this try to look through readfirstlane like GWS?
1077   if (!isDSOffsetLegal(PtrBase, Offset, 16)) {
1078     PtrBase = MI.getOperand(2).getReg();
1079     Offset = 0;
1080   }
1081 
1082   MachineBasicBlock *MBB = MI.getParent();
1083   const DebugLoc &DL = MI.getDebugLoc();
1084   const unsigned Opc = IsAppend ? AMDGPU::DS_APPEND : AMDGPU::DS_CONSUME;
1085 
1086   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1087     .addReg(PtrBase);
1088   BuildMI(*MBB, &MI, DL, TII.get(Opc), MI.getOperand(0).getReg())
1089     .addImm(Offset)
1090     .addImm(IsGDS ? -1 : 0)
1091     .cloneMemRefs(MI);
1092 
1093   MI.eraseFromParent();
1094   return true;
1095 }
1096 
1097 bool AMDGPUInstructionSelector::selectG_INTRINSIC_W_SIDE_EFFECTS(
1098     MachineInstr &I) const {
1099   unsigned IntrinsicID = I.getIntrinsicID();
1100   switch (IntrinsicID) {
1101   case Intrinsic::amdgcn_end_cf:
1102     return selectEndCfIntrinsic(I);
1103   case Intrinsic::amdgcn_ds_ordered_add:
1104   case Intrinsic::amdgcn_ds_ordered_swap:
1105     return selectDSOrderedIntrinsic(I, IntrinsicID);
1106   case Intrinsic::amdgcn_ds_gws_init:
1107   case Intrinsic::amdgcn_ds_gws_barrier:
1108   case Intrinsic::amdgcn_ds_gws_sema_v:
1109   case Intrinsic::amdgcn_ds_gws_sema_br:
1110   case Intrinsic::amdgcn_ds_gws_sema_p:
1111   case Intrinsic::amdgcn_ds_gws_sema_release_all:
1112     return selectDSGWSIntrinsic(I, IntrinsicID);
1113   case Intrinsic::amdgcn_ds_append:
1114     return selectDSAppendConsume(I, true);
1115   case Intrinsic::amdgcn_ds_consume:
1116     return selectDSAppendConsume(I, false);
1117   default:
1118     return selectImpl(I, *CoverageInfo);
1119   }
1120 }
1121 
1122 bool AMDGPUInstructionSelector::selectG_SELECT(MachineInstr &I) const {
1123   if (selectImpl(I, *CoverageInfo))
1124     return true;
1125 
1126   MachineBasicBlock *BB = I.getParent();
1127   const DebugLoc &DL = I.getDebugLoc();
1128 
1129   Register DstReg = I.getOperand(0).getReg();
1130   unsigned Size = RBI.getSizeInBits(DstReg, *MRI, TRI);
1131   assert(Size <= 32 || Size == 64);
1132   const MachineOperand &CCOp = I.getOperand(1);
1133   Register CCReg = CCOp.getReg();
1134   if (!isVCC(CCReg, *MRI)) {
1135     unsigned SelectOpcode = Size == 64 ? AMDGPU::S_CSELECT_B64 :
1136                                          AMDGPU::S_CSELECT_B32;
1137     MachineInstr *CopySCC = BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), AMDGPU::SCC)
1138             .addReg(CCReg);
1139 
1140     // The generic constrainSelectedInstRegOperands doesn't work for the scc register
1141     // bank, because it does not cover the register class that we used to represent
1142     // for it.  So we need to manually set the register class here.
1143     if (!MRI->getRegClassOrNull(CCReg))
1144         MRI->setRegClass(CCReg, TRI.getConstrainedRegClassForOperand(CCOp, *MRI));
1145     MachineInstr *Select = BuildMI(*BB, &I, DL, TII.get(SelectOpcode), DstReg)
1146             .add(I.getOperand(2))
1147             .add(I.getOperand(3));
1148 
1149     bool Ret = constrainSelectedInstRegOperands(*Select, TII, TRI, RBI) |
1150                constrainSelectedInstRegOperands(*CopySCC, TII, TRI, RBI);
1151     I.eraseFromParent();
1152     return Ret;
1153   }
1154 
1155   // Wide VGPR select should have been split in RegBankSelect.
1156   if (Size > 32)
1157     return false;
1158 
1159   MachineInstr *Select =
1160       BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_CNDMASK_B32_e64), DstReg)
1161               .addImm(0)
1162               .add(I.getOperand(3))
1163               .addImm(0)
1164               .add(I.getOperand(2))
1165               .add(I.getOperand(1));
1166 
1167   bool Ret = constrainSelectedInstRegOperands(*Select, TII, TRI, RBI);
1168   I.eraseFromParent();
1169   return Ret;
1170 }
1171 
1172 bool AMDGPUInstructionSelector::selectG_STORE(MachineInstr &I) const {
1173   initM0(I);
1174   return selectImpl(I, *CoverageInfo);
1175 }
1176 
1177 static int sizeToSubRegIndex(unsigned Size) {
1178   switch (Size) {
1179   case 32:
1180     return AMDGPU::sub0;
1181   case 64:
1182     return AMDGPU::sub0_sub1;
1183   case 96:
1184     return AMDGPU::sub0_sub1_sub2;
1185   case 128:
1186     return AMDGPU::sub0_sub1_sub2_sub3;
1187   case 256:
1188     return AMDGPU::sub0_sub1_sub2_sub3_sub4_sub5_sub6_sub7;
1189   default:
1190     if (Size < 32)
1191       return AMDGPU::sub0;
1192     if (Size > 256)
1193       return -1;
1194     return sizeToSubRegIndex(PowerOf2Ceil(Size));
1195   }
1196 }
1197 
1198 bool AMDGPUInstructionSelector::selectG_TRUNC(MachineInstr &I) const {
1199   Register DstReg = I.getOperand(0).getReg();
1200   Register SrcReg = I.getOperand(1).getReg();
1201   const LLT DstTy = MRI->getType(DstReg);
1202   const LLT SrcTy = MRI->getType(SrcReg);
1203   if (!DstTy.isScalar())
1204     return false;
1205 
1206   const LLT S1 = LLT::scalar(1);
1207 
1208   const RegisterBank *SrcRB = RBI.getRegBank(SrcReg, *MRI, TRI);
1209   const RegisterBank *DstRB;
1210   if (DstTy == S1) {
1211     // This is a special case. We don't treat s1 for legalization artifacts as
1212     // vcc booleans.
1213     DstRB = SrcRB;
1214   } else {
1215     DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
1216     if (SrcRB != DstRB)
1217       return false;
1218   }
1219 
1220   unsigned DstSize = DstTy.getSizeInBits();
1221   unsigned SrcSize = SrcTy.getSizeInBits();
1222 
1223   const TargetRegisterClass *SrcRC
1224     = TRI.getRegClassForSizeOnBank(SrcSize, *SrcRB, *MRI);
1225   const TargetRegisterClass *DstRC
1226     = TRI.getRegClassForSizeOnBank(DstSize, *DstRB, *MRI);
1227 
1228   if (SrcSize > 32) {
1229     int SubRegIdx = sizeToSubRegIndex(DstSize);
1230     if (SubRegIdx == -1)
1231       return false;
1232 
1233     // Deal with weird cases where the class only partially supports the subreg
1234     // index.
1235     SrcRC = TRI.getSubClassWithSubReg(SrcRC, SubRegIdx);
1236     if (!SrcRC)
1237       return false;
1238 
1239     I.getOperand(1).setSubReg(SubRegIdx);
1240   }
1241 
1242   if (!RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI) ||
1243       !RBI.constrainGenericRegister(DstReg, *DstRC, *MRI)) {
1244     LLVM_DEBUG(dbgs() << "Failed to constrain G_TRUNC\n");
1245     return false;
1246   }
1247 
1248   I.setDesc(TII.get(TargetOpcode::COPY));
1249   return true;
1250 }
1251 
1252 /// \returns true if a bitmask for \p Size bits will be an inline immediate.
1253 static bool shouldUseAndMask(unsigned Size, unsigned &Mask) {
1254   Mask = maskTrailingOnes<unsigned>(Size);
1255   int SignedMask = static_cast<int>(Mask);
1256   return SignedMask >= -16 && SignedMask <= 64;
1257 }
1258 
1259 // Like RegisterBankInfo::getRegBank, but don't assume vcc for s1.
1260 const RegisterBank *AMDGPUInstructionSelector::getArtifactRegBank(
1261   Register Reg, const MachineRegisterInfo &MRI,
1262   const TargetRegisterInfo &TRI) const {
1263   const RegClassOrRegBank &RegClassOrBank = MRI.getRegClassOrRegBank(Reg);
1264   if (auto *RB = RegClassOrBank.dyn_cast<const RegisterBank *>())
1265     return RB;
1266 
1267   // Ignore the type, since we don't use vcc in artifacts.
1268   if (auto *RC = RegClassOrBank.dyn_cast<const TargetRegisterClass *>())
1269     return &RBI.getRegBankFromRegClass(*RC, LLT());
1270   return nullptr;
1271 }
1272 
1273 bool AMDGPUInstructionSelector::selectG_SZA_EXT(MachineInstr &I) const {
1274   bool InReg = I.getOpcode() == AMDGPU::G_SEXT_INREG;
1275   bool Signed = I.getOpcode() == AMDGPU::G_SEXT || InReg;
1276   const DebugLoc &DL = I.getDebugLoc();
1277   MachineBasicBlock &MBB = *I.getParent();
1278   const Register DstReg = I.getOperand(0).getReg();
1279   const Register SrcReg = I.getOperand(1).getReg();
1280 
1281   const LLT DstTy = MRI->getType(DstReg);
1282   const LLT SrcTy = MRI->getType(SrcReg);
1283   const unsigned SrcSize = I.getOpcode() == AMDGPU::G_SEXT_INREG ?
1284     I.getOperand(2).getImm() : SrcTy.getSizeInBits();
1285   const unsigned DstSize = DstTy.getSizeInBits();
1286   if (!DstTy.isScalar())
1287     return false;
1288 
1289   if (I.getOpcode() == AMDGPU::G_ANYEXT)
1290     return selectCOPY(I);
1291 
1292   // Artifact casts should never use vcc.
1293   const RegisterBank *SrcBank = getArtifactRegBank(SrcReg, *MRI, TRI);
1294 
1295   if (SrcBank->getID() == AMDGPU::VGPRRegBankID && DstSize <= 32) {
1296     // 64-bit should have been split up in RegBankSelect
1297 
1298     // Try to use an and with a mask if it will save code size.
1299     unsigned Mask;
1300     if (!Signed && shouldUseAndMask(SrcSize, Mask)) {
1301       MachineInstr *ExtI =
1302       BuildMI(MBB, I, DL, TII.get(AMDGPU::V_AND_B32_e32), DstReg)
1303         .addImm(Mask)
1304         .addReg(SrcReg);
1305       I.eraseFromParent();
1306       return constrainSelectedInstRegOperands(*ExtI, TII, TRI, RBI);
1307     }
1308 
1309     const unsigned BFE = Signed ? AMDGPU::V_BFE_I32 : AMDGPU::V_BFE_U32;
1310     MachineInstr *ExtI =
1311       BuildMI(MBB, I, DL, TII.get(BFE), DstReg)
1312       .addReg(SrcReg)
1313       .addImm(0) // Offset
1314       .addImm(SrcSize); // Width
1315     I.eraseFromParent();
1316     return constrainSelectedInstRegOperands(*ExtI, TII, TRI, RBI);
1317   }
1318 
1319   if (SrcBank->getID() == AMDGPU::SGPRRegBankID && DstSize <= 64) {
1320     const TargetRegisterClass &SrcRC = InReg && DstSize > 32 ?
1321       AMDGPU::SReg_64RegClass : AMDGPU::SReg_32RegClass;
1322     if (!RBI.constrainGenericRegister(SrcReg, SrcRC, *MRI))
1323       return false;
1324 
1325     if (Signed && DstSize == 32 && (SrcSize == 8 || SrcSize == 16)) {
1326       const unsigned SextOpc = SrcSize == 8 ?
1327         AMDGPU::S_SEXT_I32_I8 : AMDGPU::S_SEXT_I32_I16;
1328       BuildMI(MBB, I, DL, TII.get(SextOpc), DstReg)
1329         .addReg(SrcReg);
1330       I.eraseFromParent();
1331       return RBI.constrainGenericRegister(DstReg, AMDGPU::SReg_32RegClass, *MRI);
1332     }
1333 
1334     const unsigned BFE64 = Signed ? AMDGPU::S_BFE_I64 : AMDGPU::S_BFE_U64;
1335     const unsigned BFE32 = Signed ? AMDGPU::S_BFE_I32 : AMDGPU::S_BFE_U32;
1336 
1337     // Scalar BFE is encoded as S1[5:0] = offset, S1[22:16]= width.
1338     if (DstSize > 32 && (SrcSize <= 32 || InReg)) {
1339       // We need a 64-bit register source, but the high bits don't matter.
1340       Register ExtReg = MRI->createVirtualRegister(&AMDGPU::SReg_64RegClass);
1341       Register UndefReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1342       unsigned SubReg = InReg ? AMDGPU::sub0 : 0;
1343 
1344       BuildMI(MBB, I, DL, TII.get(AMDGPU::IMPLICIT_DEF), UndefReg);
1345       BuildMI(MBB, I, DL, TII.get(AMDGPU::REG_SEQUENCE), ExtReg)
1346         .addReg(SrcReg, 0, SubReg)
1347         .addImm(AMDGPU::sub0)
1348         .addReg(UndefReg)
1349         .addImm(AMDGPU::sub1);
1350 
1351       BuildMI(MBB, I, DL, TII.get(BFE64), DstReg)
1352         .addReg(ExtReg)
1353         .addImm(SrcSize << 16);
1354 
1355       I.eraseFromParent();
1356       return RBI.constrainGenericRegister(DstReg, AMDGPU::SReg_64RegClass, *MRI);
1357     }
1358 
1359     unsigned Mask;
1360     if (!Signed && shouldUseAndMask(SrcSize, Mask)) {
1361       BuildMI(MBB, I, DL, TII.get(AMDGPU::S_AND_B32), DstReg)
1362         .addReg(SrcReg)
1363         .addImm(Mask);
1364     } else {
1365       BuildMI(MBB, I, DL, TII.get(BFE32), DstReg)
1366         .addReg(SrcReg)
1367         .addImm(SrcSize << 16);
1368     }
1369 
1370     I.eraseFromParent();
1371     return RBI.constrainGenericRegister(DstReg, AMDGPU::SReg_32RegClass, *MRI);
1372   }
1373 
1374   return false;
1375 }
1376 
1377 bool AMDGPUInstructionSelector::selectG_CONSTANT(MachineInstr &I) const {
1378   MachineBasicBlock *BB = I.getParent();
1379   MachineOperand &ImmOp = I.getOperand(1);
1380 
1381   // The AMDGPU backend only supports Imm operands and not CImm or FPImm.
1382   if (ImmOp.isFPImm()) {
1383     const APInt &Imm = ImmOp.getFPImm()->getValueAPF().bitcastToAPInt();
1384     ImmOp.ChangeToImmediate(Imm.getZExtValue());
1385   } else if (ImmOp.isCImm()) {
1386     ImmOp.ChangeToImmediate(ImmOp.getCImm()->getZExtValue());
1387   }
1388 
1389   Register DstReg = I.getOperand(0).getReg();
1390   unsigned Size;
1391   bool IsSgpr;
1392   const RegisterBank *RB = MRI->getRegBankOrNull(I.getOperand(0).getReg());
1393   if (RB) {
1394     IsSgpr = RB->getID() == AMDGPU::SGPRRegBankID;
1395     Size = MRI->getType(DstReg).getSizeInBits();
1396   } else {
1397     const TargetRegisterClass *RC = TRI.getRegClassForReg(*MRI, DstReg);
1398     IsSgpr = TRI.isSGPRClass(RC);
1399     Size = TRI.getRegSizeInBits(*RC);
1400   }
1401 
1402   if (Size != 32 && Size != 64)
1403     return false;
1404 
1405   unsigned Opcode = IsSgpr ? AMDGPU::S_MOV_B32 : AMDGPU::V_MOV_B32_e32;
1406   if (Size == 32) {
1407     I.setDesc(TII.get(Opcode));
1408     I.addImplicitDefUseOperands(*MF);
1409     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
1410   }
1411 
1412   const DebugLoc &DL = I.getDebugLoc();
1413 
1414   APInt Imm(Size, I.getOperand(1).getImm());
1415 
1416   MachineInstr *ResInst;
1417   if (IsSgpr && TII.isInlineConstant(Imm)) {
1418     ResInst = BuildMI(*BB, &I, DL, TII.get(AMDGPU::S_MOV_B64), DstReg)
1419       .addImm(I.getOperand(1).getImm());
1420   } else {
1421     const TargetRegisterClass *RC = IsSgpr ?
1422       &AMDGPU::SReg_32RegClass : &AMDGPU::VGPR_32RegClass;
1423     Register LoReg = MRI->createVirtualRegister(RC);
1424     Register HiReg = MRI->createVirtualRegister(RC);
1425 
1426     BuildMI(*BB, &I, DL, TII.get(Opcode), LoReg)
1427       .addImm(Imm.trunc(32).getZExtValue());
1428 
1429     BuildMI(*BB, &I, DL, TII.get(Opcode), HiReg)
1430       .addImm(Imm.ashr(32).getZExtValue());
1431 
1432     ResInst = BuildMI(*BB, &I, DL, TII.get(AMDGPU::REG_SEQUENCE), DstReg)
1433       .addReg(LoReg)
1434       .addImm(AMDGPU::sub0)
1435       .addReg(HiReg)
1436       .addImm(AMDGPU::sub1);
1437   }
1438 
1439   // We can't call constrainSelectedInstRegOperands here, because it doesn't
1440   // work for target independent opcodes
1441   I.eraseFromParent();
1442   const TargetRegisterClass *DstRC =
1443     TRI.getConstrainedRegClassForOperand(ResInst->getOperand(0), *MRI);
1444   if (!DstRC)
1445     return true;
1446   return RBI.constrainGenericRegister(DstReg, *DstRC, *MRI);
1447 }
1448 
1449 bool AMDGPUInstructionSelector::selectG_FNEG(MachineInstr &MI) const {
1450   // Only manually handle the f64 SGPR case.
1451   //
1452   // FIXME: This is a workaround for 2.5 different tablegen problems. Because
1453   // the bit ops theoretically have a second result due to the implicit def of
1454   // SCC, the GlobalISelEmitter is overly conservative and rejects it. Fixing
1455   // that is easy by disabling the check. The result works, but uses a
1456   // nonsensical sreg32orlds_and_sreg_1 regclass.
1457   //
1458   // The DAG emitter is more problematic, and incorrectly adds both S_XOR_B32 to
1459   // the variadic REG_SEQUENCE operands.
1460 
1461   Register Dst = MI.getOperand(0).getReg();
1462   const RegisterBank *DstRB = RBI.getRegBank(Dst, *MRI, TRI);
1463   if (DstRB->getID() != AMDGPU::SGPRRegBankID ||
1464       MRI->getType(Dst) != LLT::scalar(64))
1465     return false;
1466 
1467   Register Src = MI.getOperand(1).getReg();
1468   MachineInstr *Fabs = getOpcodeDef(TargetOpcode::G_FABS, Src, *MRI);
1469   if (Fabs)
1470     Src = Fabs->getOperand(1).getReg();
1471 
1472   if (!RBI.constrainGenericRegister(Src, AMDGPU::SReg_64RegClass, *MRI) ||
1473       !RBI.constrainGenericRegister(Dst, AMDGPU::SReg_64RegClass, *MRI))
1474     return false;
1475 
1476   MachineBasicBlock *BB = MI.getParent();
1477   const DebugLoc &DL = MI.getDebugLoc();
1478   Register LoReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1479   Register HiReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1480   Register ConstReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1481   Register OpReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1482 
1483   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), LoReg)
1484     .addReg(Src, 0, AMDGPU::sub0);
1485   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), HiReg)
1486     .addReg(Src, 0, AMDGPU::sub1);
1487   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::S_MOV_B32), ConstReg)
1488     .addImm(0x80000000);
1489 
1490   // Set or toggle sign bit.
1491   unsigned Opc = Fabs ? AMDGPU::S_OR_B32 : AMDGPU::S_XOR_B32;
1492   BuildMI(*BB, &MI, DL, TII.get(Opc), OpReg)
1493     .addReg(HiReg)
1494     .addReg(ConstReg);
1495   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::REG_SEQUENCE), Dst)
1496     .addReg(LoReg)
1497     .addImm(AMDGPU::sub0)
1498     .addReg(OpReg)
1499     .addImm(AMDGPU::sub1);
1500   MI.eraseFromParent();
1501   return true;
1502 }
1503 
1504 static bool isConstant(const MachineInstr &MI) {
1505   return MI.getOpcode() == TargetOpcode::G_CONSTANT;
1506 }
1507 
1508 void AMDGPUInstructionSelector::getAddrModeInfo(const MachineInstr &Load,
1509     const MachineRegisterInfo &MRI, SmallVectorImpl<GEPInfo> &AddrInfo) const {
1510 
1511   const MachineInstr *PtrMI = MRI.getUniqueVRegDef(Load.getOperand(1).getReg());
1512 
1513   assert(PtrMI);
1514 
1515   if (PtrMI->getOpcode() != TargetOpcode::G_PTR_ADD)
1516     return;
1517 
1518   GEPInfo GEPInfo(*PtrMI);
1519 
1520   for (unsigned i = 1; i != 3; ++i) {
1521     const MachineOperand &GEPOp = PtrMI->getOperand(i);
1522     const MachineInstr *OpDef = MRI.getUniqueVRegDef(GEPOp.getReg());
1523     assert(OpDef);
1524     if (i == 2 && isConstant(*OpDef)) {
1525       // TODO: Could handle constant base + variable offset, but a combine
1526       // probably should have commuted it.
1527       assert(GEPInfo.Imm == 0);
1528       GEPInfo.Imm = OpDef->getOperand(1).getCImm()->getSExtValue();
1529       continue;
1530     }
1531     const RegisterBank *OpBank = RBI.getRegBank(GEPOp.getReg(), MRI, TRI);
1532     if (OpBank->getID() == AMDGPU::SGPRRegBankID)
1533       GEPInfo.SgprParts.push_back(GEPOp.getReg());
1534     else
1535       GEPInfo.VgprParts.push_back(GEPOp.getReg());
1536   }
1537 
1538   AddrInfo.push_back(GEPInfo);
1539   getAddrModeInfo(*PtrMI, MRI, AddrInfo);
1540 }
1541 
1542 bool AMDGPUInstructionSelector::isInstrUniform(const MachineInstr &MI) const {
1543   if (!MI.hasOneMemOperand())
1544     return false;
1545 
1546   const MachineMemOperand *MMO = *MI.memoperands_begin();
1547   const Value *Ptr = MMO->getValue();
1548 
1549   // UndefValue means this is a load of a kernel input.  These are uniform.
1550   // Sometimes LDS instructions have constant pointers.
1551   // If Ptr is null, then that means this mem operand contains a
1552   // PseudoSourceValue like GOT.
1553   if (!Ptr || isa<UndefValue>(Ptr) || isa<Argument>(Ptr) ||
1554       isa<Constant>(Ptr) || isa<GlobalValue>(Ptr))
1555     return true;
1556 
1557   if (MMO->getAddrSpace() == AMDGPUAS::CONSTANT_ADDRESS_32BIT)
1558     return true;
1559 
1560   const Instruction *I = dyn_cast<Instruction>(Ptr);
1561   return I && I->getMetadata("amdgpu.uniform");
1562 }
1563 
1564 bool AMDGPUInstructionSelector::hasVgprParts(ArrayRef<GEPInfo> AddrInfo) const {
1565   for (const GEPInfo &GEPInfo : AddrInfo) {
1566     if (!GEPInfo.VgprParts.empty())
1567       return true;
1568   }
1569   return false;
1570 }
1571 
1572 void AMDGPUInstructionSelector::initM0(MachineInstr &I) const {
1573   MachineBasicBlock *BB = I.getParent();
1574 
1575   const LLT PtrTy = MRI->getType(I.getOperand(1).getReg());
1576   unsigned AS = PtrTy.getAddressSpace();
1577   if ((AS == AMDGPUAS::LOCAL_ADDRESS || AS == AMDGPUAS::REGION_ADDRESS) &&
1578       STI.ldsRequiresM0Init()) {
1579     // If DS instructions require M0 initializtion, insert it before selecting.
1580     BuildMI(*BB, &I, I.getDebugLoc(), TII.get(AMDGPU::S_MOV_B32), AMDGPU::M0)
1581       .addImm(-1);
1582   }
1583 }
1584 
1585 bool AMDGPUInstructionSelector::selectG_LOAD_ATOMICRMW(MachineInstr &I) const {
1586   initM0(I);
1587   return selectImpl(I, *CoverageInfo);
1588 }
1589 
1590 bool AMDGPUInstructionSelector::selectG_BRCOND(MachineInstr &I) const {
1591   MachineBasicBlock *BB = I.getParent();
1592   MachineOperand &CondOp = I.getOperand(0);
1593   Register CondReg = CondOp.getReg();
1594   const DebugLoc &DL = I.getDebugLoc();
1595 
1596   unsigned BrOpcode;
1597   Register CondPhysReg;
1598   const TargetRegisterClass *ConstrainRC;
1599 
1600   // In SelectionDAG, we inspect the IR block for uniformity metadata to decide
1601   // whether the branch is uniform when selecting the instruction. In
1602   // GlobalISel, we should push that decision into RegBankSelect. Assume for now
1603   // RegBankSelect knows what it's doing if the branch condition is scc, even
1604   // though it currently does not.
1605   if (!isVCC(CondReg, *MRI)) {
1606     if (MRI->getType(CondReg) != LLT::scalar(32))
1607       return false;
1608 
1609     CondPhysReg = AMDGPU::SCC;
1610     BrOpcode = AMDGPU::S_CBRANCH_SCC1;
1611     // FIXME: Hack for isSCC tests
1612     ConstrainRC = &AMDGPU::SGPR_32RegClass;
1613   } else {
1614     // FIXME: Do we have to insert an and with exec here, like in SelectionDAG?
1615     // We sort of know that a VCC producer based on the register bank, that ands
1616     // inactive lanes with 0. What if there was a logical operation with vcc
1617     // producers in different blocks/with different exec masks?
1618     // FIXME: Should scc->vcc copies and with exec?
1619     CondPhysReg = TRI.getVCC();
1620     BrOpcode = AMDGPU::S_CBRANCH_VCCNZ;
1621     ConstrainRC = TRI.getBoolRC();
1622   }
1623 
1624   if (!MRI->getRegClassOrNull(CondReg))
1625     MRI->setRegClass(CondReg, ConstrainRC);
1626 
1627   BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), CondPhysReg)
1628     .addReg(CondReg);
1629   BuildMI(*BB, &I, DL, TII.get(BrOpcode))
1630     .addMBB(I.getOperand(1).getMBB());
1631 
1632   I.eraseFromParent();
1633   return true;
1634 }
1635 
1636 bool AMDGPUInstructionSelector::selectG_FRAME_INDEX_GLOBAL_VALUE(
1637   MachineInstr &I) const {
1638   Register DstReg = I.getOperand(0).getReg();
1639   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
1640   const bool IsVGPR = DstRB->getID() == AMDGPU::VGPRRegBankID;
1641   I.setDesc(TII.get(IsVGPR ? AMDGPU::V_MOV_B32_e32 : AMDGPU::S_MOV_B32));
1642   if (IsVGPR)
1643     I.addOperand(*MF, MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
1644 
1645   return RBI.constrainGenericRegister(
1646     DstReg, IsVGPR ? AMDGPU::VGPR_32RegClass : AMDGPU::SReg_32RegClass, *MRI);
1647 }
1648 
1649 bool AMDGPUInstructionSelector::selectG_PTR_MASK(MachineInstr &I) const {
1650   uint64_t Align = I.getOperand(2).getImm();
1651   const uint64_t Mask = ~((UINT64_C(1) << Align) - 1);
1652 
1653   MachineBasicBlock *BB = I.getParent();
1654 
1655   Register DstReg = I.getOperand(0).getReg();
1656   Register SrcReg = I.getOperand(1).getReg();
1657 
1658   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
1659   const RegisterBank *SrcRB = RBI.getRegBank(SrcReg, *MRI, TRI);
1660   const bool IsVGPR = DstRB->getID() == AMDGPU::VGPRRegBankID;
1661   unsigned NewOpc = IsVGPR ? AMDGPU::V_AND_B32_e64 : AMDGPU::S_AND_B32;
1662   unsigned MovOpc = IsVGPR ? AMDGPU::V_MOV_B32_e32 : AMDGPU::S_MOV_B32;
1663   const TargetRegisterClass &RegRC
1664     = IsVGPR ? AMDGPU::VGPR_32RegClass : AMDGPU::SReg_32RegClass;
1665 
1666   LLT Ty = MRI->getType(DstReg);
1667 
1668   const TargetRegisterClass *DstRC = TRI.getRegClassForTypeOnBank(Ty, *DstRB,
1669                                                                   *MRI);
1670   const TargetRegisterClass *SrcRC = TRI.getRegClassForTypeOnBank(Ty, *SrcRB,
1671                                                                   *MRI);
1672   if (!RBI.constrainGenericRegister(DstReg, *DstRC, *MRI) ||
1673       !RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI))
1674     return false;
1675 
1676   const DebugLoc &DL = I.getDebugLoc();
1677   Register ImmReg = MRI->createVirtualRegister(&RegRC);
1678   BuildMI(*BB, &I, DL, TII.get(MovOpc), ImmReg)
1679     .addImm(Mask);
1680 
1681   if (Ty.getSizeInBits() == 32) {
1682     BuildMI(*BB, &I, DL, TII.get(NewOpc), DstReg)
1683       .addReg(SrcReg)
1684       .addReg(ImmReg);
1685     I.eraseFromParent();
1686     return true;
1687   }
1688 
1689   Register HiReg = MRI->createVirtualRegister(&RegRC);
1690   Register LoReg = MRI->createVirtualRegister(&RegRC);
1691   Register MaskLo = MRI->createVirtualRegister(&RegRC);
1692 
1693   BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), LoReg)
1694     .addReg(SrcReg, 0, AMDGPU::sub0);
1695   BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), HiReg)
1696     .addReg(SrcReg, 0, AMDGPU::sub1);
1697 
1698   BuildMI(*BB, &I, DL, TII.get(NewOpc), MaskLo)
1699     .addReg(LoReg)
1700     .addReg(ImmReg);
1701   BuildMI(*BB, &I, DL, TII.get(AMDGPU::REG_SEQUENCE), DstReg)
1702     .addReg(MaskLo)
1703     .addImm(AMDGPU::sub0)
1704     .addReg(HiReg)
1705     .addImm(AMDGPU::sub1);
1706   I.eraseFromParent();
1707   return true;
1708 }
1709 
1710 /// Return the register to use for the index value, and the subregister to use
1711 /// for the indirectly accessed register.
1712 static std::pair<Register, unsigned>
1713 computeIndirectRegIndex(MachineRegisterInfo &MRI,
1714                         const SIRegisterInfo &TRI,
1715                         const TargetRegisterClass *SuperRC,
1716                         Register IdxReg,
1717                         unsigned EltSize) {
1718   Register IdxBaseReg;
1719   int Offset;
1720   MachineInstr *Unused;
1721 
1722   std::tie(IdxBaseReg, Offset, Unused)
1723     = AMDGPU::getBaseWithConstantOffset(MRI, IdxReg);
1724 
1725   ArrayRef<int16_t> SubRegs = TRI.getRegSplitParts(SuperRC, EltSize);
1726 
1727   // Skip out of bounds offsets, or else we would end up using an undefined
1728   // register.
1729   if (static_cast<unsigned>(Offset) >= SubRegs.size())
1730     return std::make_pair(IdxReg, SubRegs[0]);
1731   return std::make_pair(IdxBaseReg, SubRegs[Offset]);
1732 }
1733 
1734 bool AMDGPUInstructionSelector::selectG_EXTRACT_VECTOR_ELT(
1735   MachineInstr &MI) const {
1736   Register DstReg = MI.getOperand(0).getReg();
1737   Register SrcReg = MI.getOperand(1).getReg();
1738   Register IdxReg = MI.getOperand(2).getReg();
1739 
1740   LLT DstTy = MRI->getType(DstReg);
1741   LLT SrcTy = MRI->getType(SrcReg);
1742 
1743   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
1744   const RegisterBank *SrcRB = RBI.getRegBank(SrcReg, *MRI, TRI);
1745   const RegisterBank *IdxRB = RBI.getRegBank(IdxReg, *MRI, TRI);
1746 
1747   // The index must be scalar. If it wasn't RegBankSelect should have moved this
1748   // into a waterfall loop.
1749   if (IdxRB->getID() != AMDGPU::SGPRRegBankID)
1750     return false;
1751 
1752   const TargetRegisterClass *SrcRC = TRI.getRegClassForTypeOnBank(SrcTy, *SrcRB,
1753                                                                   *MRI);
1754   const TargetRegisterClass *DstRC = TRI.getRegClassForTypeOnBank(DstTy, *DstRB,
1755                                                                   *MRI);
1756   if (!RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI) ||
1757       !RBI.constrainGenericRegister(DstReg, *DstRC, *MRI) ||
1758       !RBI.constrainGenericRegister(IdxReg, AMDGPU::SReg_32RegClass, *MRI))
1759     return false;
1760 
1761   MachineBasicBlock *BB = MI.getParent();
1762   const DebugLoc &DL = MI.getDebugLoc();
1763   const bool Is64 = DstTy.getSizeInBits() == 64;
1764 
1765   unsigned SubReg;
1766   std::tie(IdxReg, SubReg) = computeIndirectRegIndex(*MRI, TRI, SrcRC, IdxReg,
1767                                                      DstTy.getSizeInBits() / 8);
1768 
1769   if (SrcRB->getID() == AMDGPU::SGPRRegBankID) {
1770     if (DstTy.getSizeInBits() != 32 && !Is64)
1771       return false;
1772 
1773     BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1774       .addReg(IdxReg);
1775 
1776     unsigned Opc = Is64 ? AMDGPU::S_MOVRELS_B64 : AMDGPU::S_MOVRELS_B32;
1777     BuildMI(*BB, &MI, DL, TII.get(Opc), DstReg)
1778       .addReg(SrcReg, 0, SubReg)
1779       .addReg(SrcReg, RegState::Implicit);
1780     MI.eraseFromParent();
1781     return true;
1782   }
1783 
1784   if (SrcRB->getID() != AMDGPU::VGPRRegBankID || DstTy.getSizeInBits() != 32)
1785     return false;
1786 
1787   if (!STI.useVGPRIndexMode()) {
1788     BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1789       .addReg(IdxReg);
1790     BuildMI(*BB, &MI, DL, TII.get(AMDGPU::V_MOVRELS_B32_e32), DstReg)
1791       .addReg(SrcReg, RegState::Undef, SubReg)
1792       .addReg(SrcReg, RegState::Implicit);
1793     MI.eraseFromParent();
1794     return true;
1795   }
1796 
1797   BuildMI(*BB, MI, DL, TII.get(AMDGPU::S_SET_GPR_IDX_ON))
1798     .addReg(IdxReg)
1799     .addImm(AMDGPU::VGPRIndexMode::SRC0_ENABLE);
1800   BuildMI(*BB, MI, DL, TII.get(AMDGPU::V_MOV_B32_e32), DstReg)
1801     .addReg(SrcReg, RegState::Undef, SubReg)
1802     .addReg(SrcReg, RegState::Implicit)
1803     .addReg(AMDGPU::M0, RegState::Implicit);
1804   BuildMI(*BB, MI, DL, TII.get(AMDGPU::S_SET_GPR_IDX_OFF));
1805 
1806   MI.eraseFromParent();
1807   return true;
1808 }
1809 
1810 // TODO: Fold insert_vector_elt (extract_vector_elt) into movrelsd
1811 bool AMDGPUInstructionSelector::selectG_INSERT_VECTOR_ELT(
1812   MachineInstr &MI) const {
1813   Register DstReg = MI.getOperand(0).getReg();
1814   Register VecReg = MI.getOperand(1).getReg();
1815   Register ValReg = MI.getOperand(2).getReg();
1816   Register IdxReg = MI.getOperand(3).getReg();
1817 
1818   LLT VecTy = MRI->getType(DstReg);
1819   LLT ValTy = MRI->getType(ValReg);
1820   unsigned VecSize = VecTy.getSizeInBits();
1821   unsigned ValSize = ValTy.getSizeInBits();
1822 
1823   const RegisterBank *VecRB = RBI.getRegBank(VecReg, *MRI, TRI);
1824   const RegisterBank *ValRB = RBI.getRegBank(ValReg, *MRI, TRI);
1825   const RegisterBank *IdxRB = RBI.getRegBank(IdxReg, *MRI, TRI);
1826 
1827   assert(VecTy.getElementType() == ValTy);
1828 
1829   // The index must be scalar. If it wasn't RegBankSelect should have moved this
1830   // into a waterfall loop.
1831   if (IdxRB->getID() != AMDGPU::SGPRRegBankID)
1832     return false;
1833 
1834   const TargetRegisterClass *VecRC = TRI.getRegClassForTypeOnBank(VecTy, *VecRB,
1835                                                                   *MRI);
1836   const TargetRegisterClass *ValRC = TRI.getRegClassForTypeOnBank(ValTy, *ValRB,
1837                                                                   *MRI);
1838 
1839   if (!RBI.constrainGenericRegister(VecReg, *VecRC, *MRI) ||
1840       !RBI.constrainGenericRegister(DstReg, *VecRC, *MRI) ||
1841       !RBI.constrainGenericRegister(ValReg, *ValRC, *MRI) ||
1842       !RBI.constrainGenericRegister(IdxReg, AMDGPU::SReg_32RegClass, *MRI))
1843     return false;
1844 
1845   if (VecRB->getID() == AMDGPU::VGPRRegBankID && ValSize != 32)
1846     return false;
1847 
1848   unsigned SubReg;
1849   std::tie(IdxReg, SubReg) = computeIndirectRegIndex(*MRI, TRI, VecRC, IdxReg,
1850                                                      ValSize / 8);
1851 
1852   const bool IndexMode = VecRB->getID() == AMDGPU::VGPRRegBankID &&
1853                          STI.useVGPRIndexMode();
1854 
1855   MachineBasicBlock *BB = MI.getParent();
1856   const DebugLoc &DL = MI.getDebugLoc();
1857 
1858   if (IndexMode) {
1859     BuildMI(*BB, MI, DL, TII.get(AMDGPU::S_SET_GPR_IDX_ON))
1860       .addReg(IdxReg)
1861       .addImm(AMDGPU::VGPRIndexMode::DST_ENABLE);
1862   } else {
1863     BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1864       .addReg(IdxReg);
1865   }
1866 
1867   const MCInstrDesc &RegWriteOp
1868     = TII.getIndirectRegWritePseudo(VecSize, ValSize,
1869                                     VecRB->getID() == AMDGPU::SGPRRegBankID);
1870   BuildMI(*BB, MI, DL, RegWriteOp, DstReg)
1871     .addReg(VecReg)
1872     .addReg(ValReg)
1873     .addImm(SubReg);
1874 
1875   if (IndexMode)
1876     BuildMI(*BB, MI, DL, TII.get(AMDGPU::S_SET_GPR_IDX_OFF));
1877 
1878   MI.eraseFromParent();
1879   return true;
1880 }
1881 
1882 bool AMDGPUInstructionSelector::select(MachineInstr &I) {
1883   if (I.isPHI())
1884     return selectPHI(I);
1885 
1886   if (!I.isPreISelOpcode()) {
1887     if (I.isCopy())
1888       return selectCOPY(I);
1889     return true;
1890   }
1891 
1892   switch (I.getOpcode()) {
1893   case TargetOpcode::G_AND:
1894   case TargetOpcode::G_OR:
1895   case TargetOpcode::G_XOR:
1896     if (selectG_AND_OR_XOR(I))
1897       return true;
1898     return selectImpl(I, *CoverageInfo);
1899   case TargetOpcode::G_ADD:
1900   case TargetOpcode::G_SUB:
1901     if (selectImpl(I, *CoverageInfo))
1902       return true;
1903     return selectG_ADD_SUB(I);
1904   case TargetOpcode::G_UADDO:
1905   case TargetOpcode::G_USUBO:
1906   case TargetOpcode::G_UADDE:
1907   case TargetOpcode::G_USUBE:
1908     return selectG_UADDO_USUBO_UADDE_USUBE(I);
1909   case TargetOpcode::G_INTTOPTR:
1910   case TargetOpcode::G_BITCAST:
1911   case TargetOpcode::G_PTRTOINT:
1912     return selectCOPY(I);
1913   case TargetOpcode::G_CONSTANT:
1914   case TargetOpcode::G_FCONSTANT:
1915     return selectG_CONSTANT(I);
1916   case TargetOpcode::G_FNEG:
1917     if (selectImpl(I, *CoverageInfo))
1918       return true;
1919     return selectG_FNEG(I);
1920   case TargetOpcode::G_EXTRACT:
1921     return selectG_EXTRACT(I);
1922   case TargetOpcode::G_MERGE_VALUES:
1923   case TargetOpcode::G_BUILD_VECTOR:
1924   case TargetOpcode::G_CONCAT_VECTORS:
1925     return selectG_MERGE_VALUES(I);
1926   case TargetOpcode::G_UNMERGE_VALUES:
1927     return selectG_UNMERGE_VALUES(I);
1928   case TargetOpcode::G_PTR_ADD:
1929     return selectG_PTR_ADD(I);
1930   case TargetOpcode::G_IMPLICIT_DEF:
1931     return selectG_IMPLICIT_DEF(I);
1932   case TargetOpcode::G_INSERT:
1933     return selectG_INSERT(I);
1934   case TargetOpcode::G_INTRINSIC:
1935     return selectG_INTRINSIC(I);
1936   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
1937     return selectG_INTRINSIC_W_SIDE_EFFECTS(I);
1938   case TargetOpcode::G_ICMP:
1939     if (selectG_ICMP(I))
1940       return true;
1941     return selectImpl(I, *CoverageInfo);
1942   case TargetOpcode::G_LOAD:
1943   case TargetOpcode::G_ATOMIC_CMPXCHG:
1944   case TargetOpcode::G_ATOMICRMW_XCHG:
1945   case TargetOpcode::G_ATOMICRMW_ADD:
1946   case TargetOpcode::G_ATOMICRMW_SUB:
1947   case TargetOpcode::G_ATOMICRMW_AND:
1948   case TargetOpcode::G_ATOMICRMW_OR:
1949   case TargetOpcode::G_ATOMICRMW_XOR:
1950   case TargetOpcode::G_ATOMICRMW_MIN:
1951   case TargetOpcode::G_ATOMICRMW_MAX:
1952   case TargetOpcode::G_ATOMICRMW_UMIN:
1953   case TargetOpcode::G_ATOMICRMW_UMAX:
1954   case TargetOpcode::G_ATOMICRMW_FADD:
1955     return selectG_LOAD_ATOMICRMW(I);
1956   case TargetOpcode::G_SELECT:
1957     return selectG_SELECT(I);
1958   case TargetOpcode::G_STORE:
1959     return selectG_STORE(I);
1960   case TargetOpcode::G_TRUNC:
1961     return selectG_TRUNC(I);
1962   case TargetOpcode::G_SEXT:
1963   case TargetOpcode::G_ZEXT:
1964   case TargetOpcode::G_ANYEXT:
1965   case TargetOpcode::G_SEXT_INREG:
1966     if (selectImpl(I, *CoverageInfo))
1967       return true;
1968     return selectG_SZA_EXT(I);
1969   case TargetOpcode::G_BRCOND:
1970     return selectG_BRCOND(I);
1971   case TargetOpcode::G_FRAME_INDEX:
1972   case TargetOpcode::G_GLOBAL_VALUE:
1973     return selectG_FRAME_INDEX_GLOBAL_VALUE(I);
1974   case TargetOpcode::G_PTR_MASK:
1975     return selectG_PTR_MASK(I);
1976   case TargetOpcode::G_EXTRACT_VECTOR_ELT:
1977     return selectG_EXTRACT_VECTOR_ELT(I);
1978   case TargetOpcode::G_INSERT_VECTOR_ELT:
1979     return selectG_INSERT_VECTOR_ELT(I);
1980   case AMDGPU::G_AMDGPU_ATOMIC_INC:
1981   case AMDGPU::G_AMDGPU_ATOMIC_DEC:
1982     initM0(I);
1983     return selectImpl(I, *CoverageInfo);
1984   default:
1985     return selectImpl(I, *CoverageInfo);
1986   }
1987   return false;
1988 }
1989 
1990 InstructionSelector::ComplexRendererFns
1991 AMDGPUInstructionSelector::selectVCSRC(MachineOperand &Root) const {
1992   return {{
1993       [=](MachineInstrBuilder &MIB) { MIB.add(Root); }
1994   }};
1995 
1996 }
1997 
1998 std::pair<Register, unsigned>
1999 AMDGPUInstructionSelector::selectVOP3ModsImpl(
2000   Register Src) const {
2001   unsigned Mods = 0;
2002   MachineInstr *MI = getDefIgnoringCopies(Src, *MRI);
2003 
2004   if (MI && MI->getOpcode() == AMDGPU::G_FNEG) {
2005     Src = MI->getOperand(1).getReg();
2006     Mods |= SISrcMods::NEG;
2007     MI = getDefIgnoringCopies(Src, *MRI);
2008   }
2009 
2010   if (MI && MI->getOpcode() == AMDGPU::G_FABS) {
2011     Src = MI->getOperand(1).getReg();
2012     Mods |= SISrcMods::ABS;
2013   }
2014 
2015   return std::make_pair(Src, Mods);
2016 }
2017 
2018 ///
2019 /// This will select either an SGPR or VGPR operand and will save us from
2020 /// having to write an extra tablegen pattern.
2021 InstructionSelector::ComplexRendererFns
2022 AMDGPUInstructionSelector::selectVSRC0(MachineOperand &Root) const {
2023   return {{
2024       [=](MachineInstrBuilder &MIB) { MIB.add(Root); }
2025   }};
2026 }
2027 
2028 InstructionSelector::ComplexRendererFns
2029 AMDGPUInstructionSelector::selectVOP3Mods0(MachineOperand &Root) const {
2030   Register Src;
2031   unsigned Mods;
2032   std::tie(Src, Mods) = selectVOP3ModsImpl(Root.getReg());
2033 
2034   return {{
2035       [=](MachineInstrBuilder &MIB) { MIB.addReg(Src); },
2036       [=](MachineInstrBuilder &MIB) { MIB.addImm(Mods); }, // src0_mods
2037       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); },    // clamp
2038       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }     // omod
2039   }};
2040 }
2041 
2042 InstructionSelector::ComplexRendererFns
2043 AMDGPUInstructionSelector::selectVOP3OMods(MachineOperand &Root) const {
2044   return {{
2045       [=](MachineInstrBuilder &MIB) { MIB.add(Root); },
2046       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }, // clamp
2047       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }  // omod
2048   }};
2049 }
2050 
2051 InstructionSelector::ComplexRendererFns
2052 AMDGPUInstructionSelector::selectVOP3Mods(MachineOperand &Root) const {
2053   Register Src;
2054   unsigned Mods;
2055   std::tie(Src, Mods) = selectVOP3ModsImpl(Root.getReg());
2056 
2057   return {{
2058       [=](MachineInstrBuilder &MIB) { MIB.addReg(Src); },
2059       [=](MachineInstrBuilder &MIB) { MIB.addImm(Mods); }  // src_mods
2060   }};
2061 }
2062 
2063 InstructionSelector::ComplexRendererFns
2064 AMDGPUInstructionSelector::selectVOP3NoMods(MachineOperand &Root) const {
2065   Register Reg = Root.getReg();
2066   const MachineInstr *Def = getDefIgnoringCopies(Reg, *MRI);
2067   if (Def && (Def->getOpcode() == AMDGPU::G_FNEG ||
2068               Def->getOpcode() == AMDGPU::G_FABS))
2069     return {};
2070   return {{
2071       [=](MachineInstrBuilder &MIB) { MIB.addReg(Reg); },
2072   }};
2073 }
2074 
2075 InstructionSelector::ComplexRendererFns
2076 AMDGPUInstructionSelector::selectVOP3Mods_nnan(MachineOperand &Root) const {
2077   Register Src;
2078   unsigned Mods;
2079   std::tie(Src, Mods) = selectVOP3ModsImpl(Root.getReg());
2080   if (!TM.Options.NoNaNsFPMath && !isKnownNeverNaN(Src, *MRI))
2081     return None;
2082 
2083   return {{
2084       [=](MachineInstrBuilder &MIB) { MIB.addReg(Src); },
2085       [=](MachineInstrBuilder &MIB) { MIB.addImm(Mods); }  // src_mods
2086   }};
2087 }
2088 
2089 InstructionSelector::ComplexRendererFns
2090 AMDGPUInstructionSelector::selectVOP3OpSelMods0(MachineOperand &Root) const {
2091   // FIXME: Handle clamp and op_sel
2092   return {{
2093       [=](MachineInstrBuilder &MIB) { MIB.addReg(Root.getReg()); },
2094       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }, // src_mods
2095       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }  // clamp
2096   }};
2097 }
2098 
2099 InstructionSelector::ComplexRendererFns
2100 AMDGPUInstructionSelector::selectVOP3OpSelMods(MachineOperand &Root) const {
2101   // FIXME: Handle op_sel
2102   return {{
2103       [=](MachineInstrBuilder &MIB) { MIB.addReg(Root.getReg()); },
2104       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); } // src_mods
2105   }};
2106 }
2107 
2108 InstructionSelector::ComplexRendererFns
2109 AMDGPUInstructionSelector::selectSmrdImm(MachineOperand &Root) const {
2110   SmallVector<GEPInfo, 4> AddrInfo;
2111   getAddrModeInfo(*Root.getParent(), *MRI, AddrInfo);
2112 
2113   if (AddrInfo.empty() || AddrInfo[0].SgprParts.size() != 1)
2114     return None;
2115 
2116   const GEPInfo &GEPInfo = AddrInfo[0];
2117   Optional<int64_t> EncodedImm = AMDGPU::getSMRDEncodedOffset(STI, GEPInfo.Imm);
2118   if (!EncodedImm)
2119     return None;
2120 
2121   unsigned PtrReg = GEPInfo.SgprParts[0];
2122   return {{
2123     [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrReg); },
2124     [=](MachineInstrBuilder &MIB) { MIB.addImm(*EncodedImm); }
2125   }};
2126 }
2127 
2128 InstructionSelector::ComplexRendererFns
2129 AMDGPUInstructionSelector::selectSmrdImm32(MachineOperand &Root) const {
2130   SmallVector<GEPInfo, 4> AddrInfo;
2131   getAddrModeInfo(*Root.getParent(), *MRI, AddrInfo);
2132 
2133   if (AddrInfo.empty() || AddrInfo[0].SgprParts.size() != 1)
2134     return None;
2135 
2136   const GEPInfo &GEPInfo = AddrInfo[0];
2137   unsigned PtrReg = GEPInfo.SgprParts[0];
2138   Optional<int64_t> EncodedImm =
2139       AMDGPU::getSMRDEncodedLiteralOffset32(STI, GEPInfo.Imm);
2140   if (!EncodedImm)
2141     return None;
2142 
2143   return {{
2144     [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrReg); },
2145     [=](MachineInstrBuilder &MIB) { MIB.addImm(*EncodedImm); }
2146   }};
2147 }
2148 
2149 InstructionSelector::ComplexRendererFns
2150 AMDGPUInstructionSelector::selectSmrdSgpr(MachineOperand &Root) const {
2151   MachineInstr *MI = Root.getParent();
2152   MachineBasicBlock *MBB = MI->getParent();
2153 
2154   SmallVector<GEPInfo, 4> AddrInfo;
2155   getAddrModeInfo(*MI, *MRI, AddrInfo);
2156 
2157   // FIXME: We should shrink the GEP if the offset is known to be <= 32-bits,
2158   // then we can select all ptr + 32-bit offsets not just immediate offsets.
2159   if (AddrInfo.empty() || AddrInfo[0].SgprParts.size() != 1)
2160     return None;
2161 
2162   const GEPInfo &GEPInfo = AddrInfo[0];
2163   if (!GEPInfo.Imm || !isUInt<32>(GEPInfo.Imm))
2164     return None;
2165 
2166   // If we make it this far we have a load with an 32-bit immediate offset.
2167   // It is OK to select this using a sgpr offset, because we have already
2168   // failed trying to select this load into one of the _IMM variants since
2169   // the _IMM Patterns are considered before the _SGPR patterns.
2170   unsigned PtrReg = GEPInfo.SgprParts[0];
2171   Register OffsetReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2172   BuildMI(*MBB, MI, MI->getDebugLoc(), TII.get(AMDGPU::S_MOV_B32), OffsetReg)
2173           .addImm(GEPInfo.Imm);
2174   return {{
2175     [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrReg); },
2176     [=](MachineInstrBuilder &MIB) { MIB.addReg(OffsetReg); }
2177   }};
2178 }
2179 
2180 template <bool Signed>
2181 InstructionSelector::ComplexRendererFns
2182 AMDGPUInstructionSelector::selectFlatOffsetImpl(MachineOperand &Root) const {
2183   MachineInstr *MI = Root.getParent();
2184 
2185   InstructionSelector::ComplexRendererFns Default = {{
2186       [=](MachineInstrBuilder &MIB) { MIB.addReg(Root.getReg()); },
2187       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); },  // offset
2188       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }  // slc
2189     }};
2190 
2191   if (!STI.hasFlatInstOffsets())
2192     return Default;
2193 
2194   const MachineInstr *OpDef = MRI->getVRegDef(Root.getReg());
2195   if (!OpDef || OpDef->getOpcode() != AMDGPU::G_PTR_ADD)
2196     return Default;
2197 
2198   Optional<int64_t> Offset =
2199     getConstantVRegVal(OpDef->getOperand(2).getReg(), *MRI);
2200   if (!Offset.hasValue())
2201     return Default;
2202 
2203   unsigned AddrSpace = (*MI->memoperands_begin())->getAddrSpace();
2204   if (!TII.isLegalFLATOffset(Offset.getValue(), AddrSpace, Signed))
2205     return Default;
2206 
2207   Register BasePtr = OpDef->getOperand(1).getReg();
2208 
2209   return {{
2210       [=](MachineInstrBuilder &MIB) { MIB.addReg(BasePtr); },
2211       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset.getValue()); },
2212       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }  // slc
2213     }};
2214 }
2215 
2216 InstructionSelector::ComplexRendererFns
2217 AMDGPUInstructionSelector::selectFlatOffset(MachineOperand &Root) const {
2218   return selectFlatOffsetImpl<false>(Root);
2219 }
2220 
2221 InstructionSelector::ComplexRendererFns
2222 AMDGPUInstructionSelector::selectFlatOffsetSigned(MachineOperand &Root) const {
2223   return selectFlatOffsetImpl<true>(Root);
2224 }
2225 
2226 static bool isStackPtrRelative(const MachinePointerInfo &PtrInfo) {
2227   auto PSV = PtrInfo.V.dyn_cast<const PseudoSourceValue *>();
2228   return PSV && PSV->isStack();
2229 }
2230 
2231 InstructionSelector::ComplexRendererFns
2232 AMDGPUInstructionSelector::selectMUBUFScratchOffen(MachineOperand &Root) const {
2233   MachineInstr *MI = Root.getParent();
2234   MachineBasicBlock *MBB = MI->getParent();
2235   MachineFunction *MF = MBB->getParent();
2236   const SIMachineFunctionInfo *Info = MF->getInfo<SIMachineFunctionInfo>();
2237 
2238   int64_t Offset = 0;
2239   if (mi_match(Root.getReg(), *MRI, m_ICst(Offset))) {
2240     Register HighBits = MRI->createVirtualRegister(&AMDGPU::VGPR_32RegClass);
2241 
2242     // TODO: Should this be inside the render function? The iterator seems to
2243     // move.
2244     BuildMI(*MBB, MI, MI->getDebugLoc(), TII.get(AMDGPU::V_MOV_B32_e32),
2245             HighBits)
2246       .addImm(Offset & ~4095);
2247 
2248     return {{[=](MachineInstrBuilder &MIB) { // rsrc
2249                MIB.addReg(Info->getScratchRSrcReg());
2250              },
2251              [=](MachineInstrBuilder &MIB) { // vaddr
2252                MIB.addReg(HighBits);
2253              },
2254              [=](MachineInstrBuilder &MIB) { // soffset
2255                const MachineMemOperand *MMO = *MI->memoperands_begin();
2256                const MachinePointerInfo &PtrInfo = MMO->getPointerInfo();
2257 
2258                Register SOffsetReg = isStackPtrRelative(PtrInfo)
2259                                          ? Info->getStackPtrOffsetReg()
2260                                          : Info->getScratchWaveOffsetReg();
2261                MIB.addReg(SOffsetReg);
2262              },
2263              [=](MachineInstrBuilder &MIB) { // offset
2264                MIB.addImm(Offset & 4095);
2265              }}};
2266   }
2267 
2268   assert(Offset == 0);
2269 
2270   // Try to fold a frame index directly into the MUBUF vaddr field, and any
2271   // offsets.
2272   Optional<int> FI;
2273   Register VAddr = Root.getReg();
2274   if (const MachineInstr *RootDef = MRI->getVRegDef(Root.getReg())) {
2275     if (isBaseWithConstantOffset(Root, *MRI)) {
2276       const MachineOperand &LHS = RootDef->getOperand(1);
2277       const MachineOperand &RHS = RootDef->getOperand(2);
2278       const MachineInstr *LHSDef = MRI->getVRegDef(LHS.getReg());
2279       const MachineInstr *RHSDef = MRI->getVRegDef(RHS.getReg());
2280       if (LHSDef && RHSDef) {
2281         int64_t PossibleOffset =
2282             RHSDef->getOperand(1).getCImm()->getSExtValue();
2283         if (SIInstrInfo::isLegalMUBUFImmOffset(PossibleOffset) &&
2284             (!STI.privateMemoryResourceIsRangeChecked() ||
2285              KnownBits->signBitIsZero(LHS.getReg()))) {
2286           if (LHSDef->getOpcode() == AMDGPU::G_FRAME_INDEX)
2287             FI = LHSDef->getOperand(1).getIndex();
2288           else
2289             VAddr = LHS.getReg();
2290           Offset = PossibleOffset;
2291         }
2292       }
2293     } else if (RootDef->getOpcode() == AMDGPU::G_FRAME_INDEX) {
2294       FI = RootDef->getOperand(1).getIndex();
2295     }
2296   }
2297 
2298   // If we don't know this private access is a local stack object, it needs to
2299   // be relative to the entry point's scratch wave offset register.
2300   // TODO: Should split large offsets that don't fit like above.
2301   // TODO: Don't use scratch wave offset just because the offset didn't fit.
2302   Register SOffset = FI.hasValue() ? Info->getStackPtrOffsetReg()
2303                                    : Info->getScratchWaveOffsetReg();
2304 
2305   return {{[=](MachineInstrBuilder &MIB) { // rsrc
2306              MIB.addReg(Info->getScratchRSrcReg());
2307            },
2308            [=](MachineInstrBuilder &MIB) { // vaddr
2309              if (FI.hasValue())
2310                MIB.addFrameIndex(FI.getValue());
2311              else
2312                MIB.addReg(VAddr);
2313            },
2314            [=](MachineInstrBuilder &MIB) { // soffset
2315              MIB.addReg(SOffset);
2316            },
2317            [=](MachineInstrBuilder &MIB) { // offset
2318              MIB.addImm(Offset);
2319            }}};
2320 }
2321 
2322 bool AMDGPUInstructionSelector::isDSOffsetLegal(Register Base,
2323                                                 int64_t Offset,
2324                                                 unsigned OffsetBits) const {
2325   if ((OffsetBits == 16 && !isUInt<16>(Offset)) ||
2326       (OffsetBits == 8 && !isUInt<8>(Offset)))
2327     return false;
2328 
2329   if (STI.hasUsableDSOffset() || STI.unsafeDSOffsetFoldingEnabled())
2330     return true;
2331 
2332   // On Southern Islands instruction with a negative base value and an offset
2333   // don't seem to work.
2334   return KnownBits->signBitIsZero(Base);
2335 }
2336 
2337 InstructionSelector::ComplexRendererFns
2338 AMDGPUInstructionSelector::selectMUBUFScratchOffset(
2339     MachineOperand &Root) const {
2340   MachineInstr *MI = Root.getParent();
2341   MachineBasicBlock *MBB = MI->getParent();
2342 
2343   int64_t Offset = 0;
2344   if (!mi_match(Root.getReg(), *MRI, m_ICst(Offset)) ||
2345       !SIInstrInfo::isLegalMUBUFImmOffset(Offset))
2346     return {};
2347 
2348   const MachineFunction *MF = MBB->getParent();
2349   const SIMachineFunctionInfo *Info = MF->getInfo<SIMachineFunctionInfo>();
2350   const MachineMemOperand *MMO = *MI->memoperands_begin();
2351   const MachinePointerInfo &PtrInfo = MMO->getPointerInfo();
2352 
2353   Register SOffsetReg = isStackPtrRelative(PtrInfo)
2354                             ? Info->getStackPtrOffsetReg()
2355                             : Info->getScratchWaveOffsetReg();
2356   return {{
2357       [=](MachineInstrBuilder &MIB) {
2358         MIB.addReg(Info->getScratchRSrcReg());
2359       },                                                         // rsrc
2360       [=](MachineInstrBuilder &MIB) { MIB.addReg(SOffsetReg); }, // soffset
2361       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); }      // offset
2362   }};
2363 }
2364 
2365 std::pair<Register, unsigned>
2366 AMDGPUInstructionSelector::selectDS1Addr1OffsetImpl(MachineOperand &Root) const {
2367   const MachineInstr *RootDef = MRI->getVRegDef(Root.getReg());
2368   if (!RootDef)
2369     return std::make_pair(Root.getReg(), 0);
2370 
2371   int64_t ConstAddr = 0;
2372   if (isBaseWithConstantOffset(Root, *MRI)) {
2373     const MachineOperand &LHS = RootDef->getOperand(1);
2374     const MachineOperand &RHS = RootDef->getOperand(2);
2375     const MachineInstr *LHSDef = MRI->getVRegDef(LHS.getReg());
2376     const MachineInstr *RHSDef = MRI->getVRegDef(RHS.getReg());
2377     if (LHSDef && RHSDef) {
2378       int64_t PossibleOffset =
2379         RHSDef->getOperand(1).getCImm()->getSExtValue();
2380       if (isDSOffsetLegal(LHS.getReg(), PossibleOffset, 16)) {
2381         // (add n0, c0)
2382         return std::make_pair(LHS.getReg(), PossibleOffset);
2383       }
2384     }
2385   } else if (RootDef->getOpcode() == AMDGPU::G_SUB) {
2386     // TODO
2387 
2388 
2389   } else if (mi_match(Root.getReg(), *MRI, m_ICst(ConstAddr))) {
2390     // TODO
2391 
2392   }
2393 
2394   return std::make_pair(Root.getReg(), 0);
2395 }
2396 
2397 InstructionSelector::ComplexRendererFns
2398 AMDGPUInstructionSelector::selectDS1Addr1Offset(MachineOperand &Root) const {
2399 
2400   Register Reg;
2401   unsigned Offset;
2402   std::tie(Reg, Offset) = selectDS1Addr1OffsetImpl(Root);
2403   return {{
2404       [=](MachineInstrBuilder &MIB) { MIB.addReg(Reg); },
2405       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); }
2406     }};
2407 }
2408 
2409 InstructionSelector::ComplexRendererFns
2410 AMDGPUInstructionSelector::selectDS64Bit4ByteAligned(MachineOperand &Root) const {
2411   const MachineInstr *RootDef = MRI->getVRegDef(Root.getReg());
2412   if (!RootDef) {
2413     return {{
2414         [=](MachineInstrBuilder &MIB) { MIB.add(Root); },
2415         [=](MachineInstrBuilder &MIB) { MIB.addImm(0); },
2416         [=](MachineInstrBuilder &MIB) { MIB.addImm(1); }
2417       }};
2418   }
2419 
2420   int64_t ConstAddr = 0;
2421   Register PtrBase;
2422   int64_t Offset;
2423 
2424   std::tie(PtrBase, Offset) =
2425     getPtrBaseWithConstantOffset(Root.getReg(), *MRI);
2426 
2427   if (Offset) {
2428     int64_t DWordOffset0 = Offset / 4;
2429     int64_t DWordOffset1 = DWordOffset0 + 1;
2430     if (isDSOffsetLegal(PtrBase, DWordOffset1, 8)) {
2431       // (add n0, c0)
2432       return {{
2433           [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrBase); },
2434           [=](MachineInstrBuilder &MIB) { MIB.addImm(DWordOffset0); },
2435           [=](MachineInstrBuilder &MIB) { MIB.addImm(DWordOffset1); }
2436         }};
2437     }
2438   } else if (RootDef->getOpcode() == AMDGPU::G_SUB) {
2439     // TODO
2440 
2441   } else if (mi_match(Root.getReg(), *MRI, m_ICst(ConstAddr))) {
2442     // TODO
2443 
2444   }
2445 
2446   return {{
2447       [=](MachineInstrBuilder &MIB) { MIB.add(Root); },
2448       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); },
2449       [=](MachineInstrBuilder &MIB) { MIB.addImm(1); }
2450     }};
2451 }
2452 
2453 /// If \p Root is a G_PTR_ADD with a G_CONSTANT on the right hand side, return
2454 /// the base value with the constant offset. There may be intervening copies
2455 /// between \p Root and the identified constant. Returns \p Root, 0 if this does
2456 /// not match the pattern.
2457 std::pair<Register, int64_t>
2458 AMDGPUInstructionSelector::getPtrBaseWithConstantOffset(
2459   Register Root, const MachineRegisterInfo &MRI) const {
2460   MachineInstr *RootI = MRI.getVRegDef(Root);
2461   if (RootI->getOpcode() != TargetOpcode::G_PTR_ADD)
2462     return {Root, 0};
2463 
2464   MachineOperand &RHS = RootI->getOperand(2);
2465   Optional<ValueAndVReg> MaybeOffset
2466     = getConstantVRegValWithLookThrough(RHS.getReg(), MRI, true);
2467   if (!MaybeOffset)
2468     return {Root, 0};
2469   return {RootI->getOperand(1).getReg(), MaybeOffset->Value};
2470 }
2471 
2472 static void addZeroImm(MachineInstrBuilder &MIB) {
2473   MIB.addImm(0);
2474 }
2475 
2476 /// Return a resource descriptor for use with an arbitrary 64-bit pointer. If \p
2477 /// BasePtr is not valid, a null base pointer will be used.
2478 static Register buildRSRC(MachineIRBuilder &B, MachineRegisterInfo &MRI,
2479                           uint32_t FormatLo, uint32_t FormatHi,
2480                           Register BasePtr) {
2481   Register RSrc2 = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
2482   Register RSrc3 = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
2483   Register RSrcHi = MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass);
2484   Register RSrc = MRI.createVirtualRegister(&AMDGPU::SGPR_128RegClass);
2485 
2486   B.buildInstr(AMDGPU::S_MOV_B32)
2487     .addDef(RSrc2)
2488     .addImm(FormatLo);
2489   B.buildInstr(AMDGPU::S_MOV_B32)
2490     .addDef(RSrc3)
2491     .addImm(FormatHi);
2492 
2493   // Build the half of the subregister with the constants before building the
2494   // full 128-bit register. If we are building multiple resource descriptors,
2495   // this will allow CSEing of the 2-component register.
2496   B.buildInstr(AMDGPU::REG_SEQUENCE)
2497     .addDef(RSrcHi)
2498     .addReg(RSrc2)
2499     .addImm(AMDGPU::sub0)
2500     .addReg(RSrc3)
2501     .addImm(AMDGPU::sub1);
2502 
2503   Register RSrcLo = BasePtr;
2504   if (!BasePtr) {
2505     RSrcLo = MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass);
2506     B.buildInstr(AMDGPU::S_MOV_B64)
2507       .addDef(RSrcLo)
2508       .addImm(0);
2509   }
2510 
2511   B.buildInstr(AMDGPU::REG_SEQUENCE)
2512     .addDef(RSrc)
2513     .addReg(RSrcLo)
2514     .addImm(AMDGPU::sub0_sub1)
2515     .addReg(RSrcHi)
2516     .addImm(AMDGPU::sub2_sub3);
2517 
2518   return RSrc;
2519 }
2520 
2521 static Register buildAddr64RSrc(MachineIRBuilder &B, MachineRegisterInfo &MRI,
2522                                 const SIInstrInfo &TII, Register BasePtr) {
2523   uint64_t DefaultFormat = TII.getDefaultRsrcDataFormat();
2524 
2525   // FIXME: Why are half the "default" bits ignored based on the addressing
2526   // mode?
2527   return buildRSRC(B, MRI, 0, Hi_32(DefaultFormat), BasePtr);
2528 }
2529 
2530 static Register buildOffsetSrc(MachineIRBuilder &B, MachineRegisterInfo &MRI,
2531                                const SIInstrInfo &TII, Register BasePtr) {
2532   uint64_t DefaultFormat = TII.getDefaultRsrcDataFormat();
2533 
2534   // FIXME: Why are half the "default" bits ignored based on the addressing
2535   // mode?
2536   return buildRSRC(B, MRI, -1, Hi_32(DefaultFormat), BasePtr);
2537 }
2538 
2539 AMDGPUInstructionSelector::MUBUFAddressData
2540 AMDGPUInstructionSelector::parseMUBUFAddress(Register Src) const {
2541   MUBUFAddressData Data;
2542   Data.N0 = Src;
2543 
2544   Register PtrBase;
2545   int64_t Offset;
2546 
2547   std::tie(PtrBase, Offset) = getPtrBaseWithConstantOffset(Src, *MRI);
2548   if (isUInt<32>(Offset)) {
2549     Data.N0 = PtrBase;
2550     Data.Offset = Offset;
2551   }
2552 
2553   if (MachineInstr *InputAdd
2554       = getOpcodeDef(TargetOpcode::G_PTR_ADD, Data.N0, *MRI)) {
2555     Data.N2 = InputAdd->getOperand(1).getReg();
2556     Data.N3 = InputAdd->getOperand(2).getReg();
2557 
2558     // FIXME: Need to fix extra SGPR->VGPRcopies inserted
2559     // FIXME: Don't know this was defined by operand 0
2560     //
2561     // TODO: Remove this when we have copy folding optimizations after
2562     // RegBankSelect.
2563     Data.N2 = getDefIgnoringCopies(Data.N2, *MRI)->getOperand(0).getReg();
2564     Data.N3 = getDefIgnoringCopies(Data.N3, *MRI)->getOperand(0).getReg();
2565   }
2566 
2567   return Data;
2568 }
2569 
2570 /// Return if the addr64 mubuf mode should be used for the given address.
2571 bool AMDGPUInstructionSelector::shouldUseAddr64(MUBUFAddressData Addr) const {
2572   // (ptr_add N2, N3) -> addr64, or
2573   // (ptr_add (ptr_add N2, N3), C1) -> addr64
2574   if (Addr.N2)
2575     return true;
2576 
2577   const RegisterBank *N0Bank = RBI.getRegBank(Addr.N0, *MRI, TRI);
2578   return N0Bank->getID() == AMDGPU::VGPRRegBankID;
2579 }
2580 
2581 /// Split an immediate offset \p ImmOffset depending on whether it fits in the
2582 /// immediate field. Modifies \p ImmOffset and sets \p SOffset to the variable
2583 /// component.
2584 void AMDGPUInstructionSelector::splitIllegalMUBUFOffset(
2585   MachineIRBuilder &B, Register &SOffset, int64_t &ImmOffset) const {
2586   if (SIInstrInfo::isLegalMUBUFImmOffset(ImmOffset))
2587     return;
2588 
2589   // Illegal offset, store it in soffset.
2590   SOffset = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2591   B.buildInstr(AMDGPU::S_MOV_B32)
2592     .addDef(SOffset)
2593     .addImm(ImmOffset);
2594   ImmOffset = 0;
2595 }
2596 
2597 bool AMDGPUInstructionSelector::selectMUBUFAddr64Impl(
2598   MachineOperand &Root, Register &VAddr, Register &RSrcReg,
2599   Register &SOffset, int64_t &Offset) const {
2600   // FIXME: Predicates should stop this from reaching here.
2601   // addr64 bit was removed for volcanic islands.
2602   if (!STI.hasAddr64() || STI.useFlatForGlobal())
2603     return false;
2604 
2605   MUBUFAddressData AddrData = parseMUBUFAddress(Root.getReg());
2606   if (!shouldUseAddr64(AddrData))
2607     return false;
2608 
2609   Register N0 = AddrData.N0;
2610   Register N2 = AddrData.N2;
2611   Register N3 = AddrData.N3;
2612   Offset = AddrData.Offset;
2613 
2614   // Base pointer for the SRD.
2615   Register SRDPtr;
2616 
2617   if (N2) {
2618     if (RBI.getRegBank(N2, *MRI, TRI)->getID() == AMDGPU::VGPRRegBankID) {
2619       assert(N3);
2620       if (RBI.getRegBank(N3, *MRI, TRI)->getID() == AMDGPU::VGPRRegBankID) {
2621         // Both N2 and N3 are divergent. Use N0 (the result of the add) as the
2622         // addr64, and construct the default resource from a 0 address.
2623         VAddr = N0;
2624       } else {
2625         SRDPtr = N3;
2626         VAddr = N2;
2627       }
2628     } else {
2629       // N2 is not divergent.
2630       SRDPtr = N2;
2631       VAddr = N3;
2632     }
2633   } else if (RBI.getRegBank(N0, *MRI, TRI)->getID() == AMDGPU::VGPRRegBankID) {
2634     // Use the default null pointer in the resource
2635     VAddr = N0;
2636   } else {
2637     // N0 -> offset, or
2638     // (N0 + C1) -> offset
2639     SRDPtr = N0;
2640   }
2641 
2642   MachineIRBuilder B(*Root.getParent());
2643   RSrcReg = buildAddr64RSrc(B, *MRI, TII, SRDPtr);
2644   splitIllegalMUBUFOffset(B, SOffset, Offset);
2645   return true;
2646 }
2647 
2648 bool AMDGPUInstructionSelector::selectMUBUFOffsetImpl(
2649   MachineOperand &Root, Register &RSrcReg, Register &SOffset,
2650   int64_t &Offset) const {
2651   MUBUFAddressData AddrData = parseMUBUFAddress(Root.getReg());
2652   if (shouldUseAddr64(AddrData))
2653     return false;
2654 
2655   // N0 -> offset, or
2656   // (N0 + C1) -> offset
2657   Register SRDPtr = AddrData.N0;
2658   Offset = AddrData.Offset;
2659 
2660   // TODO: Look through extensions for 32-bit soffset.
2661   MachineIRBuilder B(*Root.getParent());
2662 
2663   RSrcReg = buildOffsetSrc(B, *MRI, TII, SRDPtr);
2664   splitIllegalMUBUFOffset(B, SOffset, Offset);
2665   return true;
2666 }
2667 
2668 InstructionSelector::ComplexRendererFns
2669 AMDGPUInstructionSelector::selectMUBUFAddr64(MachineOperand &Root) const {
2670   Register VAddr;
2671   Register RSrcReg;
2672   Register SOffset;
2673   int64_t Offset = 0;
2674 
2675   if (!selectMUBUFAddr64Impl(Root, VAddr, RSrcReg, SOffset, Offset))
2676     return {};
2677 
2678   // FIXME: Use defaulted operands for trailing 0s and remove from the complex
2679   // pattern.
2680   return {{
2681       [=](MachineInstrBuilder &MIB) {  // rsrc
2682         MIB.addReg(RSrcReg);
2683       },
2684       [=](MachineInstrBuilder &MIB) { // vaddr
2685         MIB.addReg(VAddr);
2686       },
2687       [=](MachineInstrBuilder &MIB) { // soffset
2688         if (SOffset)
2689           MIB.addReg(SOffset);
2690         else
2691           MIB.addImm(0);
2692       },
2693       [=](MachineInstrBuilder &MIB) { // offset
2694         MIB.addImm(Offset);
2695       },
2696       addZeroImm, //  glc
2697       addZeroImm, //  slc
2698       addZeroImm, //  tfe
2699       addZeroImm, //  dlc
2700       addZeroImm  //  swz
2701     }};
2702 }
2703 
2704 InstructionSelector::ComplexRendererFns
2705 AMDGPUInstructionSelector::selectMUBUFOffset(MachineOperand &Root) const {
2706   Register RSrcReg;
2707   Register SOffset;
2708   int64_t Offset = 0;
2709 
2710   if (!selectMUBUFOffsetImpl(Root, RSrcReg, SOffset, Offset))
2711     return {};
2712 
2713   return {{
2714       [=](MachineInstrBuilder &MIB) {  // rsrc
2715         MIB.addReg(RSrcReg);
2716       },
2717       [=](MachineInstrBuilder &MIB) { // soffset
2718         if (SOffset)
2719           MIB.addReg(SOffset);
2720         else
2721           MIB.addImm(0);
2722       },
2723       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); }, // offset
2724       addZeroImm, //  glc
2725       addZeroImm, //  slc
2726       addZeroImm, //  tfe
2727       addZeroImm, //  dlc
2728       addZeroImm  //  swz
2729     }};
2730 }
2731 
2732 InstructionSelector::ComplexRendererFns
2733 AMDGPUInstructionSelector::selectMUBUFAddr64Atomic(MachineOperand &Root) const {
2734   Register VAddr;
2735   Register RSrcReg;
2736   Register SOffset;
2737   int64_t Offset = 0;
2738 
2739   if (!selectMUBUFAddr64Impl(Root, VAddr, RSrcReg, SOffset, Offset))
2740     return {};
2741 
2742   // FIXME: Use defaulted operands for trailing 0s and remove from the complex
2743   // pattern.
2744   return {{
2745       [=](MachineInstrBuilder &MIB) {  // rsrc
2746         MIB.addReg(RSrcReg);
2747       },
2748       [=](MachineInstrBuilder &MIB) { // vaddr
2749         MIB.addReg(VAddr);
2750       },
2751       [=](MachineInstrBuilder &MIB) { // soffset
2752         if (SOffset)
2753           MIB.addReg(SOffset);
2754         else
2755           MIB.addImm(0);
2756       },
2757       [=](MachineInstrBuilder &MIB) { // offset
2758         MIB.addImm(Offset);
2759       },
2760       addZeroImm //  slc
2761     }};
2762 }
2763 
2764 InstructionSelector::ComplexRendererFns
2765 AMDGPUInstructionSelector::selectMUBUFOffsetAtomic(MachineOperand &Root) const {
2766   Register RSrcReg;
2767   Register SOffset;
2768   int64_t Offset = 0;
2769 
2770   if (!selectMUBUFOffsetImpl(Root, RSrcReg, SOffset, Offset))
2771     return {};
2772 
2773   return {{
2774       [=](MachineInstrBuilder &MIB) {  // rsrc
2775         MIB.addReg(RSrcReg);
2776       },
2777       [=](MachineInstrBuilder &MIB) { // soffset
2778         if (SOffset)
2779           MIB.addReg(SOffset);
2780         else
2781           MIB.addImm(0);
2782       },
2783       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); }, // offset
2784       addZeroImm //  slc
2785     }};
2786 }
2787 
2788 void AMDGPUInstructionSelector::renderTruncImm32(MachineInstrBuilder &MIB,
2789                                                  const MachineInstr &MI,
2790                                                  int OpIdx) const {
2791   assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
2792          "Expected G_CONSTANT");
2793   MIB.addImm(MI.getOperand(1).getCImm()->getSExtValue());
2794 }
2795 
2796 void AMDGPUInstructionSelector::renderNegateImm(MachineInstrBuilder &MIB,
2797                                                 const MachineInstr &MI,
2798                                                 int OpIdx) const {
2799   assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
2800          "Expected G_CONSTANT");
2801   MIB.addImm(-MI.getOperand(1).getCImm()->getSExtValue());
2802 }
2803 
2804 void AMDGPUInstructionSelector::renderBitcastImm(MachineInstrBuilder &MIB,
2805                                                  const MachineInstr &MI,
2806                                                  int OpIdx) const {
2807   assert(OpIdx == -1);
2808 
2809   const MachineOperand &Op = MI.getOperand(1);
2810   if (MI.getOpcode() == TargetOpcode::G_FCONSTANT)
2811     MIB.addImm(Op.getFPImm()->getValueAPF().bitcastToAPInt().getZExtValue());
2812   else {
2813     assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && "Expected G_CONSTANT");
2814     MIB.addImm(Op.getCImm()->getSExtValue());
2815   }
2816 }
2817 
2818 void AMDGPUInstructionSelector::renderPopcntImm(MachineInstrBuilder &MIB,
2819                                                 const MachineInstr &MI,
2820                                                 int OpIdx) const {
2821   assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
2822          "Expected G_CONSTANT");
2823   MIB.addImm(MI.getOperand(1).getCImm()->getValue().countPopulation());
2824 }
2825 
2826 /// This only really exists to satisfy DAG type checking machinery, so is a
2827 /// no-op here.
2828 void AMDGPUInstructionSelector::renderTruncTImm(MachineInstrBuilder &MIB,
2829                                                 const MachineInstr &MI,
2830                                                 int OpIdx) const {
2831   MIB.addImm(MI.getOperand(OpIdx).getImm());
2832 }
2833 
2834 void AMDGPUInstructionSelector::renderExtractGLC(MachineInstrBuilder &MIB,
2835                                                  const MachineInstr &MI,
2836                                                  int OpIdx) const {
2837   assert(OpIdx >= 0 && "expected to match an immediate operand");
2838   MIB.addImm(MI.getOperand(OpIdx).getImm() & 1);
2839 }
2840 
2841 void AMDGPUInstructionSelector::renderExtractSLC(MachineInstrBuilder &MIB,
2842                                                  const MachineInstr &MI,
2843                                                  int OpIdx) const {
2844   assert(OpIdx >= 0 && "expected to match an immediate operand");
2845   MIB.addImm((MI.getOperand(OpIdx).getImm() >> 1) & 1);
2846 }
2847 
2848 void AMDGPUInstructionSelector::renderExtractDLC(MachineInstrBuilder &MIB,
2849                                                  const MachineInstr &MI,
2850                                                  int OpIdx) const {
2851   assert(OpIdx >= 0 && "expected to match an immediate operand");
2852   MIB.addImm((MI.getOperand(OpIdx).getImm() >> 2) & 1);
2853 }
2854 
2855 void AMDGPUInstructionSelector::renderExtractSWZ(MachineInstrBuilder &MIB,
2856                                                  const MachineInstr &MI,
2857                                                  int OpIdx) const {
2858   assert(OpIdx >= 0 && "expected to match an immediate operand");
2859   MIB.addImm((MI.getOperand(OpIdx).getImm() >> 3) & 1);
2860 }
2861 
2862 bool AMDGPUInstructionSelector::isInlineImmediate16(int64_t Imm) const {
2863   return AMDGPU::isInlinableLiteral16(Imm, STI.hasInv2PiInlineImm());
2864 }
2865 
2866 bool AMDGPUInstructionSelector::isInlineImmediate32(int64_t Imm) const {
2867   return AMDGPU::isInlinableLiteral32(Imm, STI.hasInv2PiInlineImm());
2868 }
2869 
2870 bool AMDGPUInstructionSelector::isInlineImmediate64(int64_t Imm) const {
2871   return AMDGPU::isInlinableLiteral64(Imm, STI.hasInv2PiInlineImm());
2872 }
2873 
2874 bool AMDGPUInstructionSelector::isInlineImmediate(const APFloat &Imm) const {
2875   return TII.isInlineConstant(Imm);
2876 }
2877