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 "AMDGPUSubtarget.h"
19 #include "AMDGPUTargetMachine.h"
20 #include "MCTargetDesc/AMDGPUMCTargetDesc.h"
21 #include "SIMachineFunctionInfo.h"
22 #include "llvm/CodeGen/GlobalISel/GISelKnownBits.h"
23 #include "llvm/CodeGen/GlobalISel/InstructionSelector.h"
24 #include "llvm/CodeGen/GlobalISel/InstructionSelectorImpl.h"
25 #include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
26 #include "llvm/CodeGen/GlobalISel/MIPatternMatch.h"
27 #include "llvm/CodeGen/GlobalISel/Utils.h"
28 #include "llvm/CodeGen/MachineBasicBlock.h"
29 #include "llvm/CodeGen/MachineFunction.h"
30 #include "llvm/CodeGen/MachineInstr.h"
31 #include "llvm/CodeGen/MachineInstrBuilder.h"
32 #include "llvm/CodeGen/MachineRegisterInfo.h"
33 #include "llvm/IR/Type.h"
34 #include "llvm/Support/Debug.h"
35 #include "llvm/Support/raw_ostream.h"
36 
37 #define DEBUG_TYPE "amdgpu-isel"
38 
39 using namespace llvm;
40 using namespace MIPatternMatch;
41 
42 #define GET_GLOBALISEL_IMPL
43 #define AMDGPUSubtarget GCNSubtarget
44 #include "AMDGPUGenGlobalISel.inc"
45 #undef GET_GLOBALISEL_IMPL
46 #undef AMDGPUSubtarget
47 
48 AMDGPUInstructionSelector::AMDGPUInstructionSelector(
49     const GCNSubtarget &STI, const AMDGPURegisterBankInfo &RBI,
50     const AMDGPUTargetMachine &TM)
51     : InstructionSelector(), TII(*STI.getInstrInfo()),
52       TRI(*STI.getRegisterInfo()), RBI(RBI), TM(TM),
53       STI(STI),
54       EnableLateStructurizeCFG(AMDGPUTargetMachine::EnableLateStructurizeCFG),
55 #define GET_GLOBALISEL_PREDICATES_INIT
56 #include "AMDGPUGenGlobalISel.inc"
57 #undef GET_GLOBALISEL_PREDICATES_INIT
58 #define GET_GLOBALISEL_TEMPORARIES_INIT
59 #include "AMDGPUGenGlobalISel.inc"
60 #undef GET_GLOBALISEL_TEMPORARIES_INIT
61 {
62 }
63 
64 const char *AMDGPUInstructionSelector::getName() { return DEBUG_TYPE; }
65 
66 void AMDGPUInstructionSelector::setupMF(MachineFunction &MF, GISelKnownBits &KB,
67                                         CodeGenCoverage &CoverageInfo) {
68   MRI = &MF.getRegInfo();
69   InstructionSelector::setupMF(MF, KB, CoverageInfo);
70 }
71 
72 bool AMDGPUInstructionSelector::isVCC(Register Reg,
73                                       const MachineRegisterInfo &MRI) const {
74   if (Register::isPhysicalRegister(Reg))
75     return Reg == TRI.getVCC();
76 
77   auto &RegClassOrBank = MRI.getRegClassOrRegBank(Reg);
78   const TargetRegisterClass *RC =
79       RegClassOrBank.dyn_cast<const TargetRegisterClass*>();
80   if (RC) {
81     const LLT Ty = MRI.getType(Reg);
82     return RC->hasSuperClassEq(TRI.getBoolRC()) &&
83            Ty.isValid() && Ty.getSizeInBits() == 1;
84   }
85 
86   const RegisterBank *RB = RegClassOrBank.get<const RegisterBank *>();
87   return RB->getID() == AMDGPU::VCCRegBankID;
88 }
89 
90 bool AMDGPUInstructionSelector::constrainCopyLikeIntrin(MachineInstr &MI,
91                                                         unsigned NewOpc) const {
92   MI.setDesc(TII.get(NewOpc));
93   MI.RemoveOperand(1); // Remove intrinsic ID.
94   MI.addOperand(*MF, MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
95 
96   MachineOperand &Dst = MI.getOperand(0);
97   MachineOperand &Src = MI.getOperand(1);
98 
99   // TODO: This should be legalized to s32 if needed
100   if (MRI->getType(Dst.getReg()) == LLT::scalar(1))
101     return false;
102 
103   const TargetRegisterClass *DstRC
104     = TRI.getConstrainedRegClassForOperand(Dst, *MRI);
105   const TargetRegisterClass *SrcRC
106     = TRI.getConstrainedRegClassForOperand(Src, *MRI);
107   if (!DstRC || DstRC != SrcRC)
108     return false;
109 
110   return RBI.constrainGenericRegister(Dst.getReg(), *DstRC, *MRI) &&
111          RBI.constrainGenericRegister(Src.getReg(), *SrcRC, *MRI);
112 }
113 
114 bool AMDGPUInstructionSelector::selectCOPY(MachineInstr &I) const {
115   const DebugLoc &DL = I.getDebugLoc();
116   MachineBasicBlock *BB = I.getParent();
117   I.setDesc(TII.get(TargetOpcode::COPY));
118 
119   const MachineOperand &Src = I.getOperand(1);
120   MachineOperand &Dst = I.getOperand(0);
121   Register DstReg = Dst.getReg();
122   Register SrcReg = Src.getReg();
123 
124   if (isVCC(DstReg, *MRI)) {
125     if (SrcReg == AMDGPU::SCC) {
126       const TargetRegisterClass *RC
127         = TRI.getConstrainedRegClassForOperand(Dst, *MRI);
128       if (!RC)
129         return true;
130       return RBI.constrainGenericRegister(DstReg, *RC, *MRI);
131     }
132 
133     if (!isVCC(SrcReg, *MRI)) {
134       // TODO: Should probably leave the copy and let copyPhysReg expand it.
135       if (!RBI.constrainGenericRegister(DstReg, *TRI.getBoolRC(), *MRI))
136         return false;
137 
138       const TargetRegisterClass *SrcRC
139         = TRI.getConstrainedRegClassForOperand(Src, *MRI);
140 
141       Register MaskedReg = MRI->createVirtualRegister(SrcRC);
142 
143       // We can't trust the high bits at this point, so clear them.
144 
145       // TODO: Skip masking high bits if def is known boolean.
146 
147       unsigned AndOpc = TRI.isSGPRClass(SrcRC) ?
148         AMDGPU::S_AND_B32 : AMDGPU::V_AND_B32_e32;
149       BuildMI(*BB, &I, DL, TII.get(AndOpc), MaskedReg)
150         .addImm(1)
151         .addReg(SrcReg);
152       BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_CMP_NE_U32_e64), DstReg)
153         .addImm(0)
154         .addReg(MaskedReg);
155 
156       if (!MRI->getRegClassOrNull(SrcReg))
157         MRI->setRegClass(SrcReg, SrcRC);
158       I.eraseFromParent();
159       return true;
160     }
161 
162     const TargetRegisterClass *RC =
163       TRI.getConstrainedRegClassForOperand(Dst, *MRI);
164     if (RC && !RBI.constrainGenericRegister(DstReg, *RC, *MRI))
165       return false;
166 
167     // Don't constrain the source register to a class so the def instruction
168     // handles it (unless it's undef).
169     //
170     // FIXME: This is a hack. When selecting the def, we neeed to know
171     // specifically know that the result is VCCRegBank, and not just an SGPR
172     // with size 1. An SReg_32 with size 1 is ambiguous with wave32.
173     if (Src.isUndef()) {
174       const TargetRegisterClass *SrcRC =
175         TRI.getConstrainedRegClassForOperand(Src, *MRI);
176       if (SrcRC && !RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI))
177         return false;
178     }
179 
180     return true;
181   }
182 
183   for (const MachineOperand &MO : I.operands()) {
184     if (Register::isPhysicalRegister(MO.getReg()))
185       continue;
186 
187     const TargetRegisterClass *RC =
188             TRI.getConstrainedRegClassForOperand(MO, *MRI);
189     if (!RC)
190       continue;
191     RBI.constrainGenericRegister(MO.getReg(), *RC, *MRI);
192   }
193   return true;
194 }
195 
196 bool AMDGPUInstructionSelector::selectPHI(MachineInstr &I) const {
197   const Register DefReg = I.getOperand(0).getReg();
198   const LLT DefTy = MRI->getType(DefReg);
199 
200   // TODO: Verify this doesn't have insane operands (i.e. VGPR to SGPR copy)
201 
202   const RegClassOrRegBank &RegClassOrBank =
203     MRI->getRegClassOrRegBank(DefReg);
204 
205   const TargetRegisterClass *DefRC
206     = RegClassOrBank.dyn_cast<const TargetRegisterClass *>();
207   if (!DefRC) {
208     if (!DefTy.isValid()) {
209       LLVM_DEBUG(dbgs() << "PHI operand has no type, not a gvreg?\n");
210       return false;
211     }
212 
213     const RegisterBank &RB = *RegClassOrBank.get<const RegisterBank *>();
214     DefRC = TRI.getRegClassForTypeOnBank(DefTy, RB, *MRI);
215     if (!DefRC) {
216       LLVM_DEBUG(dbgs() << "PHI operand has unexpected size/bank\n");
217       return false;
218     }
219   }
220 
221   // TODO: Verify that all registers have the same bank
222   I.setDesc(TII.get(TargetOpcode::PHI));
223   return RBI.constrainGenericRegister(DefReg, *DefRC, *MRI);
224 }
225 
226 MachineOperand
227 AMDGPUInstructionSelector::getSubOperand64(MachineOperand &MO,
228                                            const TargetRegisterClass &SubRC,
229                                            unsigned SubIdx) const {
230 
231   MachineInstr *MI = MO.getParent();
232   MachineBasicBlock *BB = MO.getParent()->getParent();
233   Register DstReg = MRI->createVirtualRegister(&SubRC);
234 
235   if (MO.isReg()) {
236     unsigned ComposedSubIdx = TRI.composeSubRegIndices(MO.getSubReg(), SubIdx);
237     Register Reg = MO.getReg();
238     BuildMI(*BB, MI, MI->getDebugLoc(), TII.get(AMDGPU::COPY), DstReg)
239             .addReg(Reg, 0, ComposedSubIdx);
240 
241     return MachineOperand::CreateReg(DstReg, MO.isDef(), MO.isImplicit(),
242                                      MO.isKill(), MO.isDead(), MO.isUndef(),
243                                      MO.isEarlyClobber(), 0, MO.isDebug(),
244                                      MO.isInternalRead());
245   }
246 
247   assert(MO.isImm());
248 
249   APInt Imm(64, MO.getImm());
250 
251   switch (SubIdx) {
252   default:
253     llvm_unreachable("do not know to split immediate with this sub index.");
254   case AMDGPU::sub0:
255     return MachineOperand::CreateImm(Imm.getLoBits(32).getSExtValue());
256   case AMDGPU::sub1:
257     return MachineOperand::CreateImm(Imm.getHiBits(32).getSExtValue());
258   }
259 }
260 
261 static unsigned getLogicalBitOpcode(unsigned Opc, bool Is64) {
262   switch (Opc) {
263   case AMDGPU::G_AND:
264     return Is64 ? AMDGPU::S_AND_B64 : AMDGPU::S_AND_B32;
265   case AMDGPU::G_OR:
266     return Is64 ? AMDGPU::S_OR_B64 : AMDGPU::S_OR_B32;
267   case AMDGPU::G_XOR:
268     return Is64 ? AMDGPU::S_XOR_B64 : AMDGPU::S_XOR_B32;
269   default:
270     llvm_unreachable("not a bit op");
271   }
272 }
273 
274 bool AMDGPUInstructionSelector::selectG_AND_OR_XOR(MachineInstr &I) const {
275   MachineOperand &Dst = I.getOperand(0);
276   MachineOperand &Src0 = I.getOperand(1);
277   MachineOperand &Src1 = I.getOperand(2);
278   Register DstReg = Dst.getReg();
279   unsigned Size = RBI.getSizeInBits(DstReg, *MRI, TRI);
280 
281   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
282   if (DstRB->getID() == AMDGPU::VCCRegBankID) {
283     const TargetRegisterClass *RC = TRI.getBoolRC();
284     unsigned InstOpc = getLogicalBitOpcode(I.getOpcode(),
285                                            RC == &AMDGPU::SReg_64RegClass);
286     I.setDesc(TII.get(InstOpc));
287     // Dead implicit-def of scc
288     I.addOperand(MachineOperand::CreateReg(AMDGPU::SCC, true, // isDef
289                                            true, // isImp
290                                            false, // isKill
291                                            true)); // isDead
292 
293     // FIXME: Hack to avoid turning the register bank into a register class.
294     // The selector for G_ICMP relies on seeing the register bank for the result
295     // is VCC. In wave32 if we constrain the registers to SReg_32 here, it will
296     // be ambiguous whether it's a scalar or vector bool.
297     if (Src0.isUndef() && !MRI->getRegClassOrNull(Src0.getReg()))
298       MRI->setRegClass(Src0.getReg(), RC);
299     if (Src1.isUndef() && !MRI->getRegClassOrNull(Src1.getReg()))
300       MRI->setRegClass(Src1.getReg(), RC);
301 
302     return RBI.constrainGenericRegister(DstReg, *RC, *MRI);
303   }
304 
305   // TODO: Should this allow an SCC bank result, and produce a copy from SCC for
306   // the result?
307   if (DstRB->getID() == AMDGPU::SGPRRegBankID) {
308     unsigned InstOpc = getLogicalBitOpcode(I.getOpcode(), Size > 32);
309     I.setDesc(TII.get(InstOpc));
310     // Dead implicit-def of scc
311     I.addOperand(MachineOperand::CreateReg(AMDGPU::SCC, true, // isDef
312                                            true, // isImp
313                                            false, // isKill
314                                            true)); // isDead
315     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
316   }
317 
318   return false;
319 }
320 
321 bool AMDGPUInstructionSelector::selectG_ADD_SUB(MachineInstr &I) const {
322   MachineBasicBlock *BB = I.getParent();
323   MachineFunction *MF = BB->getParent();
324   Register DstReg = I.getOperand(0).getReg();
325   const DebugLoc &DL = I.getDebugLoc();
326   unsigned Size = RBI.getSizeInBits(DstReg, *MRI, TRI);
327   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
328   const bool IsSALU = DstRB->getID() == AMDGPU::SGPRRegBankID;
329   const bool Sub = I.getOpcode() == TargetOpcode::G_SUB;
330 
331   if (Size == 32) {
332     if (IsSALU) {
333       const unsigned Opc = Sub ? AMDGPU::S_SUB_U32 : AMDGPU::S_ADD_U32;
334       MachineInstr *Add =
335         BuildMI(*BB, &I, DL, TII.get(Opc), DstReg)
336         .add(I.getOperand(1))
337         .add(I.getOperand(2));
338       I.eraseFromParent();
339       return constrainSelectedInstRegOperands(*Add, TII, TRI, RBI);
340     }
341 
342     if (STI.hasAddNoCarry()) {
343       const unsigned Opc = Sub ? AMDGPU::V_SUB_U32_e64 : AMDGPU::V_ADD_U32_e64;
344       I.setDesc(TII.get(Opc));
345       I.addOperand(*MF, MachineOperand::CreateImm(0));
346       I.addOperand(*MF, MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
347       return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
348     }
349 
350     const unsigned Opc = Sub ? AMDGPU::V_SUB_I32_e64 : AMDGPU::V_ADD_I32_e64;
351 
352     Register UnusedCarry = MRI->createVirtualRegister(TRI.getWaveMaskRegClass());
353     MachineInstr *Add
354       = BuildMI(*BB, &I, DL, TII.get(Opc), DstReg)
355       .addDef(UnusedCarry, RegState::Dead)
356       .add(I.getOperand(1))
357       .add(I.getOperand(2))
358       .addImm(0);
359     I.eraseFromParent();
360     return constrainSelectedInstRegOperands(*Add, TII, TRI, RBI);
361   }
362 
363   assert(!Sub && "illegal sub should not reach here");
364 
365   const TargetRegisterClass &RC
366     = IsSALU ? AMDGPU::SReg_64_XEXECRegClass : AMDGPU::VReg_64RegClass;
367   const TargetRegisterClass &HalfRC
368     = IsSALU ? AMDGPU::SReg_32RegClass : AMDGPU::VGPR_32RegClass;
369 
370   MachineOperand Lo1(getSubOperand64(I.getOperand(1), HalfRC, AMDGPU::sub0));
371   MachineOperand Lo2(getSubOperand64(I.getOperand(2), HalfRC, AMDGPU::sub0));
372   MachineOperand Hi1(getSubOperand64(I.getOperand(1), HalfRC, AMDGPU::sub1));
373   MachineOperand Hi2(getSubOperand64(I.getOperand(2), HalfRC, AMDGPU::sub1));
374 
375   Register DstLo = MRI->createVirtualRegister(&HalfRC);
376   Register DstHi = MRI->createVirtualRegister(&HalfRC);
377 
378   if (IsSALU) {
379     BuildMI(*BB, &I, DL, TII.get(AMDGPU::S_ADD_U32), DstLo)
380       .add(Lo1)
381       .add(Lo2);
382     BuildMI(*BB, &I, DL, TII.get(AMDGPU::S_ADDC_U32), DstHi)
383       .add(Hi1)
384       .add(Hi2);
385   } else {
386     const TargetRegisterClass *CarryRC = TRI.getWaveMaskRegClass();
387     Register CarryReg = MRI->createVirtualRegister(CarryRC);
388     BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_ADD_I32_e64), DstLo)
389       .addDef(CarryReg)
390       .add(Lo1)
391       .add(Lo2)
392       .addImm(0);
393     MachineInstr *Addc = BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_ADDC_U32_e64), DstHi)
394       .addDef(MRI->createVirtualRegister(CarryRC), RegState::Dead)
395       .add(Hi1)
396       .add(Hi2)
397       .addReg(CarryReg, RegState::Kill)
398       .addImm(0);
399 
400     if (!constrainSelectedInstRegOperands(*Addc, TII, TRI, RBI))
401       return false;
402   }
403 
404   BuildMI(*BB, &I, DL, TII.get(AMDGPU::REG_SEQUENCE), DstReg)
405     .addReg(DstLo)
406     .addImm(AMDGPU::sub0)
407     .addReg(DstHi)
408     .addImm(AMDGPU::sub1);
409 
410 
411   if (!RBI.constrainGenericRegister(DstReg, RC, *MRI))
412     return false;
413 
414   I.eraseFromParent();
415   return true;
416 }
417 
418 bool AMDGPUInstructionSelector::selectG_UADDO_USUBO_UADDE_USUBE(
419   MachineInstr &I) const {
420   MachineBasicBlock *BB = I.getParent();
421   MachineFunction *MF = BB->getParent();
422   const DebugLoc &DL = I.getDebugLoc();
423   Register Dst0Reg = I.getOperand(0).getReg();
424   Register Dst1Reg = I.getOperand(1).getReg();
425   const bool IsAdd = I.getOpcode() == AMDGPU::G_UADDO ||
426                      I.getOpcode() == AMDGPU::G_UADDE;
427   const bool HasCarryIn = I.getOpcode() == AMDGPU::G_UADDE ||
428                           I.getOpcode() == AMDGPU::G_USUBE;
429 
430   if (isVCC(Dst1Reg, *MRI)) {
431       // The name of the opcodes are misleading. v_add_i32/v_sub_i32 have unsigned
432       // carry out despite the _i32 name. These were renamed in VI to _U32.
433       // FIXME: We should probably rename the opcodes here.
434     unsigned NoCarryOpc = IsAdd ? AMDGPU::V_ADD_I32_e64 : AMDGPU::V_SUB_I32_e64;
435     unsigned CarryOpc = IsAdd ? AMDGPU::V_ADDC_U32_e64 : AMDGPU::V_SUBB_U32_e64;
436     I.setDesc(TII.get(HasCarryIn ? CarryOpc : NoCarryOpc));
437     I.addOperand(*MF, MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
438     I.addOperand(*MF, MachineOperand::CreateImm(0));
439     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
440   }
441 
442   Register Src0Reg = I.getOperand(2).getReg();
443   Register Src1Reg = I.getOperand(3).getReg();
444 
445   if (HasCarryIn) {
446     BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), AMDGPU::SCC)
447       .addReg(I.getOperand(4).getReg());
448   }
449 
450   unsigned NoCarryOpc = IsAdd ? AMDGPU::S_ADD_U32 : AMDGPU::S_SUB_U32;
451   unsigned CarryOpc = IsAdd ? AMDGPU::S_ADDC_U32 : AMDGPU::S_SUBB_U32;
452 
453   BuildMI(*BB, &I, DL, TII.get(HasCarryIn ? CarryOpc : NoCarryOpc), Dst0Reg)
454     .add(I.getOperand(2))
455     .add(I.getOperand(3));
456   BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), Dst1Reg)
457     .addReg(AMDGPU::SCC);
458 
459   if (!MRI->getRegClassOrNull(Dst1Reg))
460     MRI->setRegClass(Dst1Reg, &AMDGPU::SReg_32RegClass);
461 
462   if (!RBI.constrainGenericRegister(Dst0Reg, AMDGPU::SReg_32RegClass, *MRI) ||
463       !RBI.constrainGenericRegister(Src0Reg, AMDGPU::SReg_32RegClass, *MRI) ||
464       !RBI.constrainGenericRegister(Src1Reg, AMDGPU::SReg_32RegClass, *MRI))
465     return false;
466 
467   if (HasCarryIn &&
468       !RBI.constrainGenericRegister(I.getOperand(4).getReg(),
469                                     AMDGPU::SReg_32RegClass, *MRI))
470     return false;
471 
472   I.eraseFromParent();
473   return true;
474 }
475 
476 // TODO: We should probably legalize these to only using 32-bit results.
477 bool AMDGPUInstructionSelector::selectG_EXTRACT(MachineInstr &I) const {
478   MachineBasicBlock *BB = I.getParent();
479   Register DstReg = I.getOperand(0).getReg();
480   Register SrcReg = I.getOperand(1).getReg();
481   LLT DstTy = MRI->getType(DstReg);
482   LLT SrcTy = MRI->getType(SrcReg);
483   const unsigned SrcSize = SrcTy.getSizeInBits();
484   const unsigned DstSize = DstTy.getSizeInBits();
485 
486   // TODO: Should handle any multiple of 32 offset.
487   unsigned Offset = I.getOperand(2).getImm();
488   if (Offset % 32 != 0 || DstSize > 128)
489     return false;
490 
491   const TargetRegisterClass *DstRC =
492     TRI.getConstrainedRegClassForOperand(I.getOperand(0), *MRI);
493   if (!DstRC || !RBI.constrainGenericRegister(DstReg, *DstRC, *MRI))
494     return false;
495 
496   const RegisterBank *SrcBank = RBI.getRegBank(SrcReg, *MRI, TRI);
497   const TargetRegisterClass *SrcRC =
498     TRI.getRegClassForSizeOnBank(SrcSize, *SrcBank, *MRI);
499   if (!SrcRC)
500     return false;
501   unsigned SubReg = SIRegisterInfo::getSubRegFromChannel(Offset / 32,
502                                                          DstSize / 32);
503   SrcRC = TRI.getSubClassWithSubReg(SrcRC, SubReg);
504   if (!SrcRC)
505     return false;
506 
507   SrcReg = constrainOperandRegClass(*MF, TRI, *MRI, TII, RBI, I,
508                                     *SrcRC, I.getOperand(1));
509   const DebugLoc &DL = I.getDebugLoc();
510   BuildMI(*BB, &I, DL, TII.get(TargetOpcode::COPY), DstReg)
511     .addReg(SrcReg, 0, SubReg);
512 
513   I.eraseFromParent();
514   return true;
515 }
516 
517 bool AMDGPUInstructionSelector::selectG_MERGE_VALUES(MachineInstr &MI) const {
518   MachineBasicBlock *BB = MI.getParent();
519   Register DstReg = MI.getOperand(0).getReg();
520   LLT DstTy = MRI->getType(DstReg);
521   LLT SrcTy = MRI->getType(MI.getOperand(1).getReg());
522 
523   const unsigned SrcSize = SrcTy.getSizeInBits();
524   if (SrcSize < 32)
525     return selectImpl(MI, *CoverageInfo);
526 
527   const DebugLoc &DL = MI.getDebugLoc();
528   const RegisterBank *DstBank = RBI.getRegBank(DstReg, *MRI, TRI);
529   const unsigned DstSize = DstTy.getSizeInBits();
530   const TargetRegisterClass *DstRC =
531     TRI.getRegClassForSizeOnBank(DstSize, *DstBank, *MRI);
532   if (!DstRC)
533     return false;
534 
535   ArrayRef<int16_t> SubRegs = TRI.getRegSplitParts(DstRC, SrcSize / 8);
536   MachineInstrBuilder MIB =
537     BuildMI(*BB, &MI, DL, TII.get(TargetOpcode::REG_SEQUENCE), DstReg);
538   for (int I = 0, E = MI.getNumOperands() - 1; I != E; ++I) {
539     MachineOperand &Src = MI.getOperand(I + 1);
540     MIB.addReg(Src.getReg(), getUndefRegState(Src.isUndef()));
541     MIB.addImm(SubRegs[I]);
542 
543     const TargetRegisterClass *SrcRC
544       = TRI.getConstrainedRegClassForOperand(Src, *MRI);
545     if (SrcRC && !RBI.constrainGenericRegister(Src.getReg(), *SrcRC, *MRI))
546       return false;
547   }
548 
549   if (!RBI.constrainGenericRegister(DstReg, *DstRC, *MRI))
550     return false;
551 
552   MI.eraseFromParent();
553   return true;
554 }
555 
556 bool AMDGPUInstructionSelector::selectG_UNMERGE_VALUES(MachineInstr &MI) const {
557   MachineBasicBlock *BB = MI.getParent();
558   const int NumDst = MI.getNumOperands() - 1;
559 
560   MachineOperand &Src = MI.getOperand(NumDst);
561 
562   Register SrcReg = Src.getReg();
563   Register DstReg0 = MI.getOperand(0).getReg();
564   LLT DstTy = MRI->getType(DstReg0);
565   LLT SrcTy = MRI->getType(SrcReg);
566 
567   const unsigned DstSize = DstTy.getSizeInBits();
568   const unsigned SrcSize = SrcTy.getSizeInBits();
569   const DebugLoc &DL = MI.getDebugLoc();
570   const RegisterBank *SrcBank = RBI.getRegBank(SrcReg, *MRI, TRI);
571 
572   const TargetRegisterClass *SrcRC =
573     TRI.getRegClassForSizeOnBank(SrcSize, *SrcBank, *MRI);
574   if (!SrcRC || !RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI))
575     return false;
576 
577   const unsigned SrcFlags = getUndefRegState(Src.isUndef());
578 
579   // Note we could have mixed SGPR and VGPR destination banks for an SGPR
580   // source, and this relies on the fact that the same subregister indices are
581   // used for both.
582   ArrayRef<int16_t> SubRegs = TRI.getRegSplitParts(SrcRC, DstSize / 8);
583   for (int I = 0, E = NumDst; I != E; ++I) {
584     MachineOperand &Dst = MI.getOperand(I);
585     BuildMI(*BB, &MI, DL, TII.get(TargetOpcode::COPY), Dst.getReg())
586       .addReg(SrcReg, SrcFlags, SubRegs[I]);
587 
588     const TargetRegisterClass *DstRC =
589       TRI.getConstrainedRegClassForOperand(Dst, *MRI);
590     if (DstRC && !RBI.constrainGenericRegister(Dst.getReg(), *DstRC, *MRI))
591       return false;
592   }
593 
594   MI.eraseFromParent();
595   return true;
596 }
597 
598 bool AMDGPUInstructionSelector::selectG_PTR_ADD(MachineInstr &I) const {
599   return selectG_ADD_SUB(I);
600 }
601 
602 bool AMDGPUInstructionSelector::selectG_IMPLICIT_DEF(MachineInstr &I) const {
603   const MachineOperand &MO = I.getOperand(0);
604 
605   // FIXME: Interface for getConstrainedRegClassForOperand needs work. The
606   // regbank check here is to know why getConstrainedRegClassForOperand failed.
607   const TargetRegisterClass *RC = TRI.getConstrainedRegClassForOperand(MO, *MRI);
608   if ((!RC && !MRI->getRegBankOrNull(MO.getReg())) ||
609       (RC && RBI.constrainGenericRegister(MO.getReg(), *RC, *MRI))) {
610     I.setDesc(TII.get(TargetOpcode::IMPLICIT_DEF));
611     return true;
612   }
613 
614   return false;
615 }
616 
617 bool AMDGPUInstructionSelector::selectG_INSERT(MachineInstr &I) const {
618   MachineBasicBlock *BB = I.getParent();
619 
620   Register DstReg = I.getOperand(0).getReg();
621   Register Src0Reg = I.getOperand(1).getReg();
622   Register Src1Reg = I.getOperand(2).getReg();
623   LLT Src1Ty = MRI->getType(Src1Reg);
624 
625   unsigned DstSize = MRI->getType(DstReg).getSizeInBits();
626   unsigned InsSize = Src1Ty.getSizeInBits();
627 
628   int64_t Offset = I.getOperand(3).getImm();
629   if (Offset % 32 != 0)
630     return false;
631 
632   unsigned SubReg = TRI.getSubRegFromChannel(Offset / 32, InsSize / 32);
633   if (SubReg == AMDGPU::NoSubRegister)
634     return false;
635 
636   const RegisterBank *DstBank = RBI.getRegBank(DstReg, *MRI, TRI);
637   const TargetRegisterClass *DstRC =
638     TRI.getRegClassForSizeOnBank(DstSize, *DstBank, *MRI);
639   if (!DstRC)
640     return false;
641 
642   const RegisterBank *Src0Bank = RBI.getRegBank(Src0Reg, *MRI, TRI);
643   const RegisterBank *Src1Bank = RBI.getRegBank(Src1Reg, *MRI, TRI);
644   const TargetRegisterClass *Src0RC =
645     TRI.getRegClassForSizeOnBank(DstSize, *Src0Bank, *MRI);
646   const TargetRegisterClass *Src1RC =
647     TRI.getRegClassForSizeOnBank(InsSize, *Src1Bank, *MRI);
648 
649   // Deal with weird cases where the class only partially supports the subreg
650   // index.
651   Src0RC = TRI.getSubClassWithSubReg(Src0RC, SubReg);
652   if (!Src0RC)
653     return false;
654 
655   if (!RBI.constrainGenericRegister(DstReg, *DstRC, *MRI) ||
656       !RBI.constrainGenericRegister(Src0Reg, *Src0RC, *MRI) ||
657       !RBI.constrainGenericRegister(Src1Reg, *Src1RC, *MRI))
658     return false;
659 
660   const DebugLoc &DL = I.getDebugLoc();
661   BuildMI(*BB, &I, DL, TII.get(TargetOpcode::INSERT_SUBREG), DstReg)
662     .addReg(Src0Reg)
663     .addReg(Src1Reg)
664     .addImm(SubReg);
665 
666   I.eraseFromParent();
667   return true;
668 }
669 
670 bool AMDGPUInstructionSelector::selectInterpP1F16(MachineInstr &MI) const {
671   if (STI.getLDSBankCount() != 16)
672     return selectImpl(MI, *CoverageInfo);
673 
674   Register Dst = MI.getOperand(0).getReg();
675   Register Src0 = MI.getOperand(2).getReg();
676   Register M0Val = MI.getOperand(6).getReg();
677   if (!RBI.constrainGenericRegister(M0Val, AMDGPU::SReg_32RegClass, *MRI) ||
678       !RBI.constrainGenericRegister(Dst, AMDGPU::VGPR_32RegClass, *MRI) ||
679       !RBI.constrainGenericRegister(Src0, AMDGPU::VGPR_32RegClass, *MRI))
680     return false;
681 
682   // This requires 2 instructions. It is possible to write a pattern to support
683   // this, but the generated isel emitter doesn't correctly deal with multiple
684   // output instructions using the same physical register input. The copy to m0
685   // is incorrectly placed before the second instruction.
686   //
687   // TODO: Match source modifiers.
688 
689   Register InterpMov = MRI->createVirtualRegister(&AMDGPU::VGPR_32RegClass);
690   const DebugLoc &DL = MI.getDebugLoc();
691   MachineBasicBlock *MBB = MI.getParent();
692 
693   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
694     .addReg(M0Val);
695   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::V_INTERP_MOV_F32), InterpMov)
696     .addImm(2)
697     .addImm(MI.getOperand(4).getImm())  // $attr
698     .addImm(MI.getOperand(3).getImm()); // $attrchan
699 
700   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::V_INTERP_P1LV_F16), Dst)
701     .addImm(0)                          // $src0_modifiers
702     .addReg(Src0)                       // $src0
703     .addImm(MI.getOperand(4).getImm())  // $attr
704     .addImm(MI.getOperand(3).getImm())  // $attrchan
705     .addImm(0)                          // $src2_modifiers
706     .addReg(InterpMov)                  // $src2 - 2 f16 values selected by high
707     .addImm(MI.getOperand(5).getImm())  // $high
708     .addImm(0)                          // $clamp
709     .addImm(0);                         // $omod
710 
711   MI.eraseFromParent();
712   return true;
713 }
714 
715 bool AMDGPUInstructionSelector::selectG_INTRINSIC(MachineInstr &I) const {
716   unsigned IntrinsicID = I.getIntrinsicID();
717   switch (IntrinsicID) {
718   case Intrinsic::amdgcn_if_break: {
719     MachineBasicBlock *BB = I.getParent();
720 
721     // FIXME: Manually selecting to avoid dealiing with the SReg_1 trick
722     // SelectionDAG uses for wave32 vs wave64.
723     BuildMI(*BB, &I, I.getDebugLoc(), TII.get(AMDGPU::SI_IF_BREAK))
724       .add(I.getOperand(0))
725       .add(I.getOperand(2))
726       .add(I.getOperand(3));
727 
728     Register DstReg = I.getOperand(0).getReg();
729     Register Src0Reg = I.getOperand(2).getReg();
730     Register Src1Reg = I.getOperand(3).getReg();
731 
732     I.eraseFromParent();
733 
734     for (Register Reg : { DstReg, Src0Reg, Src1Reg })
735       MRI->setRegClass(Reg, TRI.getWaveMaskRegClass());
736 
737     return true;
738   }
739   case Intrinsic::amdgcn_interp_p1_f16:
740     return selectInterpP1F16(I);
741   case Intrinsic::amdgcn_wqm:
742     return constrainCopyLikeIntrin(I, AMDGPU::WQM);
743   case Intrinsic::amdgcn_softwqm:
744     return constrainCopyLikeIntrin(I, AMDGPU::SOFT_WQM);
745   case Intrinsic::amdgcn_wwm:
746     return constrainCopyLikeIntrin(I, AMDGPU::WWM);
747   default:
748     return selectImpl(I, *CoverageInfo);
749   }
750 }
751 
752 static int getV_CMPOpcode(CmpInst::Predicate P, unsigned Size) {
753   if (Size != 32 && Size != 64)
754     return -1;
755   switch (P) {
756   default:
757     llvm_unreachable("Unknown condition code!");
758   case CmpInst::ICMP_NE:
759     return Size == 32 ? AMDGPU::V_CMP_NE_U32_e64 : AMDGPU::V_CMP_NE_U64_e64;
760   case CmpInst::ICMP_EQ:
761     return Size == 32 ? AMDGPU::V_CMP_EQ_U32_e64 : AMDGPU::V_CMP_EQ_U64_e64;
762   case CmpInst::ICMP_SGT:
763     return Size == 32 ? AMDGPU::V_CMP_GT_I32_e64 : AMDGPU::V_CMP_GT_I64_e64;
764   case CmpInst::ICMP_SGE:
765     return Size == 32 ? AMDGPU::V_CMP_GE_I32_e64 : AMDGPU::V_CMP_GE_I64_e64;
766   case CmpInst::ICMP_SLT:
767     return Size == 32 ? AMDGPU::V_CMP_LT_I32_e64 : AMDGPU::V_CMP_LT_I64_e64;
768   case CmpInst::ICMP_SLE:
769     return Size == 32 ? AMDGPU::V_CMP_LE_I32_e64 : AMDGPU::V_CMP_LE_I64_e64;
770   case CmpInst::ICMP_UGT:
771     return Size == 32 ? AMDGPU::V_CMP_GT_U32_e64 : AMDGPU::V_CMP_GT_U64_e64;
772   case CmpInst::ICMP_UGE:
773     return Size == 32 ? AMDGPU::V_CMP_GE_U32_e64 : AMDGPU::V_CMP_GE_U64_e64;
774   case CmpInst::ICMP_ULT:
775     return Size == 32 ? AMDGPU::V_CMP_LT_U32_e64 : AMDGPU::V_CMP_LT_U64_e64;
776   case CmpInst::ICMP_ULE:
777     return Size == 32 ? AMDGPU::V_CMP_LE_U32_e64 : AMDGPU::V_CMP_LE_U64_e64;
778   }
779 }
780 
781 int AMDGPUInstructionSelector::getS_CMPOpcode(CmpInst::Predicate P,
782                                               unsigned Size) const {
783   if (Size == 64) {
784     if (!STI.hasScalarCompareEq64())
785       return -1;
786 
787     switch (P) {
788     case CmpInst::ICMP_NE:
789       return AMDGPU::S_CMP_LG_U64;
790     case CmpInst::ICMP_EQ:
791       return AMDGPU::S_CMP_EQ_U64;
792     default:
793       return -1;
794     }
795   }
796 
797   if (Size != 32)
798     return -1;
799 
800   switch (P) {
801   case CmpInst::ICMP_NE:
802     return AMDGPU::S_CMP_LG_U32;
803   case CmpInst::ICMP_EQ:
804     return AMDGPU::S_CMP_EQ_U32;
805   case CmpInst::ICMP_SGT:
806     return AMDGPU::S_CMP_GT_I32;
807   case CmpInst::ICMP_SGE:
808     return AMDGPU::S_CMP_GE_I32;
809   case CmpInst::ICMP_SLT:
810     return AMDGPU::S_CMP_LT_I32;
811   case CmpInst::ICMP_SLE:
812     return AMDGPU::S_CMP_LE_I32;
813   case CmpInst::ICMP_UGT:
814     return AMDGPU::S_CMP_GT_U32;
815   case CmpInst::ICMP_UGE:
816     return AMDGPU::S_CMP_GE_U32;
817   case CmpInst::ICMP_ULT:
818     return AMDGPU::S_CMP_LT_U32;
819   case CmpInst::ICMP_ULE:
820     return AMDGPU::S_CMP_LE_U32;
821   default:
822     llvm_unreachable("Unknown condition code!");
823   }
824 }
825 
826 bool AMDGPUInstructionSelector::selectG_ICMP(MachineInstr &I) const {
827   MachineBasicBlock *BB = I.getParent();
828   const DebugLoc &DL = I.getDebugLoc();
829 
830   Register SrcReg = I.getOperand(2).getReg();
831   unsigned Size = RBI.getSizeInBits(SrcReg, *MRI, TRI);
832 
833   auto Pred = (CmpInst::Predicate)I.getOperand(1).getPredicate();
834 
835   Register CCReg = I.getOperand(0).getReg();
836   if (!isVCC(CCReg, *MRI)) {
837     int Opcode = getS_CMPOpcode(Pred, Size);
838     if (Opcode == -1)
839       return false;
840     MachineInstr *ICmp = BuildMI(*BB, &I, DL, TII.get(Opcode))
841             .add(I.getOperand(2))
842             .add(I.getOperand(3));
843     BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), CCReg)
844       .addReg(AMDGPU::SCC);
845     bool Ret =
846         constrainSelectedInstRegOperands(*ICmp, TII, TRI, RBI) &&
847         RBI.constrainGenericRegister(CCReg, AMDGPU::SReg_32RegClass, *MRI);
848     I.eraseFromParent();
849     return Ret;
850   }
851 
852   int Opcode = getV_CMPOpcode(Pred, Size);
853   if (Opcode == -1)
854     return false;
855 
856   MachineInstr *ICmp = BuildMI(*BB, &I, DL, TII.get(Opcode),
857             I.getOperand(0).getReg())
858             .add(I.getOperand(2))
859             .add(I.getOperand(3));
860   RBI.constrainGenericRegister(ICmp->getOperand(0).getReg(),
861                                *TRI.getBoolRC(), *MRI);
862   bool Ret = constrainSelectedInstRegOperands(*ICmp, TII, TRI, RBI);
863   I.eraseFromParent();
864   return Ret;
865 }
866 
867 bool AMDGPUInstructionSelector::selectEndCfIntrinsic(MachineInstr &MI) const {
868   // FIXME: Manually selecting to avoid dealiing with the SReg_1 trick
869   // SelectionDAG uses for wave32 vs wave64.
870   MachineBasicBlock *BB = MI.getParent();
871   BuildMI(*BB, &MI, MI.getDebugLoc(), TII.get(AMDGPU::SI_END_CF))
872       .add(MI.getOperand(1));
873 
874   Register Reg = MI.getOperand(1).getReg();
875   MI.eraseFromParent();
876 
877   if (!MRI->getRegClassOrNull(Reg))
878     MRI->setRegClass(Reg, TRI.getWaveMaskRegClass());
879   return true;
880 }
881 
882 static unsigned getDSShaderTypeValue(const MachineFunction &MF) {
883   switch (MF.getFunction().getCallingConv()) {
884   case CallingConv::AMDGPU_PS:
885     return 1;
886   case CallingConv::AMDGPU_VS:
887     return 2;
888   case CallingConv::AMDGPU_GS:
889     return 3;
890   case CallingConv::AMDGPU_HS:
891   case CallingConv::AMDGPU_LS:
892   case CallingConv::AMDGPU_ES:
893     report_fatal_error("ds_ordered_count unsupported for this calling conv");
894   case CallingConv::AMDGPU_CS:
895   case CallingConv::AMDGPU_KERNEL:
896   case CallingConv::C:
897   case CallingConv::Fast:
898   default:
899     // Assume other calling conventions are various compute callable functions
900     return 0;
901   }
902 }
903 
904 bool AMDGPUInstructionSelector::selectDSOrderedIntrinsic(
905   MachineInstr &MI, Intrinsic::ID IntrID) const {
906   MachineBasicBlock *MBB = MI.getParent();
907   MachineFunction *MF = MBB->getParent();
908   const DebugLoc &DL = MI.getDebugLoc();
909 
910   unsigned IndexOperand = MI.getOperand(7).getImm();
911   bool WaveRelease = MI.getOperand(8).getImm() != 0;
912   bool WaveDone = MI.getOperand(9).getImm() != 0;
913 
914   if (WaveDone && !WaveRelease)
915     report_fatal_error("ds_ordered_count: wave_done requires wave_release");
916 
917   unsigned OrderedCountIndex = IndexOperand & 0x3f;
918   IndexOperand &= ~0x3f;
919   unsigned CountDw = 0;
920 
921   if (STI.getGeneration() >= AMDGPUSubtarget::GFX10) {
922     CountDw = (IndexOperand >> 24) & 0xf;
923     IndexOperand &= ~(0xf << 24);
924 
925     if (CountDw < 1 || CountDw > 4) {
926       report_fatal_error(
927         "ds_ordered_count: dword count must be between 1 and 4");
928     }
929   }
930 
931   if (IndexOperand)
932     report_fatal_error("ds_ordered_count: bad index operand");
933 
934   unsigned Instruction = IntrID == Intrinsic::amdgcn_ds_ordered_add ? 0 : 1;
935   unsigned ShaderType = getDSShaderTypeValue(*MF);
936 
937   unsigned Offset0 = OrderedCountIndex << 2;
938   unsigned Offset1 = WaveRelease | (WaveDone << 1) | (ShaderType << 2) |
939                      (Instruction << 4);
940 
941   if (STI.getGeneration() >= AMDGPUSubtarget::GFX10)
942     Offset1 |= (CountDw - 1) << 6;
943 
944   unsigned Offset = Offset0 | (Offset1 << 8);
945 
946   Register M0Val = MI.getOperand(2).getReg();
947   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
948     .addReg(M0Val);
949 
950   Register DstReg = MI.getOperand(0).getReg();
951   Register ValReg = MI.getOperand(3).getReg();
952   MachineInstrBuilder DS =
953     BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::DS_ORDERED_COUNT), DstReg)
954       .addReg(ValReg)
955       .addImm(Offset)
956       .cloneMemRefs(MI);
957 
958   if (!RBI.constrainGenericRegister(M0Val, AMDGPU::SReg_32RegClass, *MRI))
959     return false;
960 
961   bool Ret = constrainSelectedInstRegOperands(*DS, TII, TRI, RBI);
962   MI.eraseFromParent();
963   return Ret;
964 }
965 
966 static unsigned gwsIntrinToOpcode(unsigned IntrID) {
967   switch (IntrID) {
968   case Intrinsic::amdgcn_ds_gws_init:
969     return AMDGPU::DS_GWS_INIT;
970   case Intrinsic::amdgcn_ds_gws_barrier:
971     return AMDGPU::DS_GWS_BARRIER;
972   case Intrinsic::amdgcn_ds_gws_sema_v:
973     return AMDGPU::DS_GWS_SEMA_V;
974   case Intrinsic::amdgcn_ds_gws_sema_br:
975     return AMDGPU::DS_GWS_SEMA_BR;
976   case Intrinsic::amdgcn_ds_gws_sema_p:
977     return AMDGPU::DS_GWS_SEMA_P;
978   case Intrinsic::amdgcn_ds_gws_sema_release_all:
979     return AMDGPU::DS_GWS_SEMA_RELEASE_ALL;
980   default:
981     llvm_unreachable("not a gws intrinsic");
982   }
983 }
984 
985 bool AMDGPUInstructionSelector::selectDSGWSIntrinsic(MachineInstr &MI,
986                                                      Intrinsic::ID IID) const {
987   if (IID == Intrinsic::amdgcn_ds_gws_sema_release_all &&
988       !STI.hasGWSSemaReleaseAll())
989     return false;
990 
991   // intrinsic ID, vsrc, offset
992   const bool HasVSrc = MI.getNumOperands() == 3;
993   assert(HasVSrc || MI.getNumOperands() == 2);
994 
995   Register BaseOffset = MI.getOperand(HasVSrc ? 2 : 1).getReg();
996   const RegisterBank *OffsetRB = RBI.getRegBank(BaseOffset, *MRI, TRI);
997   if (OffsetRB->getID() != AMDGPU::SGPRRegBankID)
998     return false;
999 
1000   MachineInstr *OffsetDef = getDefIgnoringCopies(BaseOffset, *MRI);
1001   assert(OffsetDef);
1002 
1003   unsigned ImmOffset;
1004 
1005   MachineBasicBlock *MBB = MI.getParent();
1006   const DebugLoc &DL = MI.getDebugLoc();
1007 
1008   MachineInstr *Readfirstlane = nullptr;
1009 
1010   // If we legalized the VGPR input, strip out the readfirstlane to analyze the
1011   // incoming offset, in case there's an add of a constant. We'll have to put it
1012   // back later.
1013   if (OffsetDef->getOpcode() == AMDGPU::V_READFIRSTLANE_B32) {
1014     Readfirstlane = OffsetDef;
1015     BaseOffset = OffsetDef->getOperand(1).getReg();
1016     OffsetDef = getDefIgnoringCopies(BaseOffset, *MRI);
1017   }
1018 
1019   if (OffsetDef->getOpcode() == AMDGPU::G_CONSTANT) {
1020     // If we have a constant offset, try to use the 0 in m0 as the base.
1021     // TODO: Look into changing the default m0 initialization value. If the
1022     // default -1 only set the low 16-bits, we could leave it as-is and add 1 to
1023     // the immediate offset.
1024 
1025     ImmOffset = OffsetDef->getOperand(1).getCImm()->getZExtValue();
1026     BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::S_MOV_B32), AMDGPU::M0)
1027       .addImm(0);
1028   } else {
1029     std::tie(BaseOffset, ImmOffset, OffsetDef)
1030       = AMDGPU::getBaseWithConstantOffset(*MRI, BaseOffset);
1031 
1032     if (Readfirstlane) {
1033       // We have the constant offset now, so put the readfirstlane back on the
1034       // variable component.
1035       if (!RBI.constrainGenericRegister(BaseOffset, AMDGPU::VGPR_32RegClass, *MRI))
1036         return false;
1037 
1038       Readfirstlane->getOperand(1).setReg(BaseOffset);
1039       BaseOffset = Readfirstlane->getOperand(0).getReg();
1040     } else {
1041       if (!RBI.constrainGenericRegister(BaseOffset,
1042                                         AMDGPU::SReg_32RegClass, *MRI))
1043         return false;
1044     }
1045 
1046     Register M0Base = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1047     BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::S_LSHL_B32), M0Base)
1048       .addReg(BaseOffset)
1049       .addImm(16);
1050 
1051     BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1052       .addReg(M0Base);
1053   }
1054 
1055   // The resource id offset is computed as (<isa opaque base> + M0[21:16] +
1056   // offset field) % 64. Some versions of the programming guide omit the m0
1057   // part, or claim it's from offset 0.
1058   auto MIB = BuildMI(*MBB, &MI, DL, TII.get(gwsIntrinToOpcode(IID)));
1059 
1060   if (HasVSrc) {
1061     Register VSrc = MI.getOperand(1).getReg();
1062     MIB.addReg(VSrc);
1063     if (!RBI.constrainGenericRegister(VSrc, AMDGPU::VGPR_32RegClass, *MRI))
1064       return false;
1065   }
1066 
1067   MIB.addImm(ImmOffset)
1068      .addImm(-1) // $gds
1069      .cloneMemRefs(MI);
1070 
1071   MI.eraseFromParent();
1072   return true;
1073 }
1074 
1075 bool AMDGPUInstructionSelector::selectDSAppendConsume(MachineInstr &MI,
1076                                                       bool IsAppend) const {
1077   Register PtrBase = MI.getOperand(2).getReg();
1078   LLT PtrTy = MRI->getType(PtrBase);
1079   bool IsGDS = PtrTy.getAddressSpace() == AMDGPUAS::REGION_ADDRESS;
1080 
1081   unsigned Offset;
1082   std::tie(PtrBase, Offset) = selectDS1Addr1OffsetImpl(MI.getOperand(2));
1083 
1084   // TODO: Should this try to look through readfirstlane like GWS?
1085   if (!isDSOffsetLegal(PtrBase, Offset, 16)) {
1086     PtrBase = MI.getOperand(2).getReg();
1087     Offset = 0;
1088   }
1089 
1090   MachineBasicBlock *MBB = MI.getParent();
1091   const DebugLoc &DL = MI.getDebugLoc();
1092   const unsigned Opc = IsAppend ? AMDGPU::DS_APPEND : AMDGPU::DS_CONSUME;
1093 
1094   BuildMI(*MBB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1095     .addReg(PtrBase);
1096   BuildMI(*MBB, &MI, DL, TII.get(Opc), MI.getOperand(0).getReg())
1097     .addImm(Offset)
1098     .addImm(IsGDS ? -1 : 0)
1099     .cloneMemRefs(MI);
1100 
1101   MI.eraseFromParent();
1102   return true;
1103 }
1104 
1105 bool AMDGPUInstructionSelector::selectG_INTRINSIC_W_SIDE_EFFECTS(
1106     MachineInstr &I) const {
1107   unsigned IntrinsicID = I.getIntrinsicID();
1108   switch (IntrinsicID) {
1109   case Intrinsic::amdgcn_end_cf:
1110     return selectEndCfIntrinsic(I);
1111   case Intrinsic::amdgcn_ds_ordered_add:
1112   case Intrinsic::amdgcn_ds_ordered_swap:
1113     return selectDSOrderedIntrinsic(I, IntrinsicID);
1114   case Intrinsic::amdgcn_ds_gws_init:
1115   case Intrinsic::amdgcn_ds_gws_barrier:
1116   case Intrinsic::amdgcn_ds_gws_sema_v:
1117   case Intrinsic::amdgcn_ds_gws_sema_br:
1118   case Intrinsic::amdgcn_ds_gws_sema_p:
1119   case Intrinsic::amdgcn_ds_gws_sema_release_all:
1120     return selectDSGWSIntrinsic(I, IntrinsicID);
1121   case Intrinsic::amdgcn_ds_append:
1122     return selectDSAppendConsume(I, true);
1123   case Intrinsic::amdgcn_ds_consume:
1124     return selectDSAppendConsume(I, false);
1125   default:
1126     return selectImpl(I, *CoverageInfo);
1127   }
1128 }
1129 
1130 bool AMDGPUInstructionSelector::selectG_SELECT(MachineInstr &I) const {
1131   if (selectImpl(I, *CoverageInfo))
1132     return true;
1133 
1134   MachineBasicBlock *BB = I.getParent();
1135   const DebugLoc &DL = I.getDebugLoc();
1136 
1137   Register DstReg = I.getOperand(0).getReg();
1138   unsigned Size = RBI.getSizeInBits(DstReg, *MRI, TRI);
1139   assert(Size <= 32 || Size == 64);
1140   const MachineOperand &CCOp = I.getOperand(1);
1141   Register CCReg = CCOp.getReg();
1142   if (!isVCC(CCReg, *MRI)) {
1143     unsigned SelectOpcode = Size == 64 ? AMDGPU::S_CSELECT_B64 :
1144                                          AMDGPU::S_CSELECT_B32;
1145     MachineInstr *CopySCC = BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), AMDGPU::SCC)
1146             .addReg(CCReg);
1147 
1148     // The generic constrainSelectedInstRegOperands doesn't work for the scc register
1149     // bank, because it does not cover the register class that we used to represent
1150     // for it.  So we need to manually set the register class here.
1151     if (!MRI->getRegClassOrNull(CCReg))
1152         MRI->setRegClass(CCReg, TRI.getConstrainedRegClassForOperand(CCOp, *MRI));
1153     MachineInstr *Select = BuildMI(*BB, &I, DL, TII.get(SelectOpcode), DstReg)
1154             .add(I.getOperand(2))
1155             .add(I.getOperand(3));
1156 
1157     bool Ret = constrainSelectedInstRegOperands(*Select, TII, TRI, RBI) |
1158                constrainSelectedInstRegOperands(*CopySCC, TII, TRI, RBI);
1159     I.eraseFromParent();
1160     return Ret;
1161   }
1162 
1163   // Wide VGPR select should have been split in RegBankSelect.
1164   if (Size > 32)
1165     return false;
1166 
1167   MachineInstr *Select =
1168       BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_CNDMASK_B32_e64), DstReg)
1169               .addImm(0)
1170               .add(I.getOperand(3))
1171               .addImm(0)
1172               .add(I.getOperand(2))
1173               .add(I.getOperand(1));
1174 
1175   bool Ret = constrainSelectedInstRegOperands(*Select, TII, TRI, RBI);
1176   I.eraseFromParent();
1177   return Ret;
1178 }
1179 
1180 bool AMDGPUInstructionSelector::selectG_STORE(MachineInstr &I) const {
1181   initM0(I);
1182   return selectImpl(I, *CoverageInfo);
1183 }
1184 
1185 static int sizeToSubRegIndex(unsigned Size) {
1186   switch (Size) {
1187   case 32:
1188     return AMDGPU::sub0;
1189   case 64:
1190     return AMDGPU::sub0_sub1;
1191   case 96:
1192     return AMDGPU::sub0_sub1_sub2;
1193   case 128:
1194     return AMDGPU::sub0_sub1_sub2_sub3;
1195   case 256:
1196     return AMDGPU::sub0_sub1_sub2_sub3_sub4_sub5_sub6_sub7;
1197   default:
1198     if (Size < 32)
1199       return AMDGPU::sub0;
1200     if (Size > 256)
1201       return -1;
1202     return sizeToSubRegIndex(PowerOf2Ceil(Size));
1203   }
1204 }
1205 
1206 bool AMDGPUInstructionSelector::selectG_TRUNC(MachineInstr &I) const {
1207   Register DstReg = I.getOperand(0).getReg();
1208   Register SrcReg = I.getOperand(1).getReg();
1209   const LLT DstTy = MRI->getType(DstReg);
1210   const LLT SrcTy = MRI->getType(SrcReg);
1211   if (!DstTy.isScalar())
1212     return false;
1213 
1214   const LLT S1 = LLT::scalar(1);
1215 
1216   const RegisterBank *SrcRB = RBI.getRegBank(SrcReg, *MRI, TRI);
1217   const RegisterBank *DstRB;
1218   if (DstTy == S1) {
1219     // This is a special case. We don't treat s1 for legalization artifacts as
1220     // vcc booleans.
1221     DstRB = SrcRB;
1222   } else {
1223     DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
1224     if (SrcRB != DstRB)
1225       return false;
1226   }
1227 
1228   unsigned DstSize = DstTy.getSizeInBits();
1229   unsigned SrcSize = SrcTy.getSizeInBits();
1230 
1231   const TargetRegisterClass *SrcRC
1232     = TRI.getRegClassForSizeOnBank(SrcSize, *SrcRB, *MRI);
1233   const TargetRegisterClass *DstRC
1234     = TRI.getRegClassForSizeOnBank(DstSize, *DstRB, *MRI);
1235 
1236   if (SrcSize > 32) {
1237     int SubRegIdx = sizeToSubRegIndex(DstSize);
1238     if (SubRegIdx == -1)
1239       return false;
1240 
1241     // Deal with weird cases where the class only partially supports the subreg
1242     // index.
1243     SrcRC = TRI.getSubClassWithSubReg(SrcRC, SubRegIdx);
1244     if (!SrcRC)
1245       return false;
1246 
1247     I.getOperand(1).setSubReg(SubRegIdx);
1248   }
1249 
1250   if (!RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI) ||
1251       !RBI.constrainGenericRegister(DstReg, *DstRC, *MRI)) {
1252     LLVM_DEBUG(dbgs() << "Failed to constrain G_TRUNC\n");
1253     return false;
1254   }
1255 
1256   I.setDesc(TII.get(TargetOpcode::COPY));
1257   return true;
1258 }
1259 
1260 /// \returns true if a bitmask for \p Size bits will be an inline immediate.
1261 static bool shouldUseAndMask(unsigned Size, unsigned &Mask) {
1262   Mask = maskTrailingOnes<unsigned>(Size);
1263   int SignedMask = static_cast<int>(Mask);
1264   return SignedMask >= -16 && SignedMask <= 64;
1265 }
1266 
1267 // Like RegisterBankInfo::getRegBank, but don't assume vcc for s1.
1268 const RegisterBank *AMDGPUInstructionSelector::getArtifactRegBank(
1269   Register Reg, const MachineRegisterInfo &MRI,
1270   const TargetRegisterInfo &TRI) const {
1271   const RegClassOrRegBank &RegClassOrBank = MRI.getRegClassOrRegBank(Reg);
1272   if (auto *RB = RegClassOrBank.dyn_cast<const RegisterBank *>())
1273     return RB;
1274 
1275   // Ignore the type, since we don't use vcc in artifacts.
1276   if (auto *RC = RegClassOrBank.dyn_cast<const TargetRegisterClass *>())
1277     return &RBI.getRegBankFromRegClass(*RC, LLT());
1278   return nullptr;
1279 }
1280 
1281 bool AMDGPUInstructionSelector::selectG_SZA_EXT(MachineInstr &I) const {
1282   bool InReg = I.getOpcode() == AMDGPU::G_SEXT_INREG;
1283   bool Signed = I.getOpcode() == AMDGPU::G_SEXT || InReg;
1284   const DebugLoc &DL = I.getDebugLoc();
1285   MachineBasicBlock &MBB = *I.getParent();
1286   const Register DstReg = I.getOperand(0).getReg();
1287   const Register SrcReg = I.getOperand(1).getReg();
1288 
1289   const LLT DstTy = MRI->getType(DstReg);
1290   const LLT SrcTy = MRI->getType(SrcReg);
1291   const unsigned SrcSize = I.getOpcode() == AMDGPU::G_SEXT_INREG ?
1292     I.getOperand(2).getImm() : SrcTy.getSizeInBits();
1293   const unsigned DstSize = DstTy.getSizeInBits();
1294   if (!DstTy.isScalar())
1295     return false;
1296 
1297   if (I.getOpcode() == AMDGPU::G_ANYEXT)
1298     return selectCOPY(I);
1299 
1300   // Artifact casts should never use vcc.
1301   const RegisterBank *SrcBank = getArtifactRegBank(SrcReg, *MRI, TRI);
1302 
1303   if (SrcBank->getID() == AMDGPU::VGPRRegBankID && DstSize <= 32) {
1304     // 64-bit should have been split up in RegBankSelect
1305 
1306     // Try to use an and with a mask if it will save code size.
1307     unsigned Mask;
1308     if (!Signed && shouldUseAndMask(SrcSize, Mask)) {
1309       MachineInstr *ExtI =
1310       BuildMI(MBB, I, DL, TII.get(AMDGPU::V_AND_B32_e32), DstReg)
1311         .addImm(Mask)
1312         .addReg(SrcReg);
1313       I.eraseFromParent();
1314       return constrainSelectedInstRegOperands(*ExtI, TII, TRI, RBI);
1315     }
1316 
1317     const unsigned BFE = Signed ? AMDGPU::V_BFE_I32 : AMDGPU::V_BFE_U32;
1318     MachineInstr *ExtI =
1319       BuildMI(MBB, I, DL, TII.get(BFE), DstReg)
1320       .addReg(SrcReg)
1321       .addImm(0) // Offset
1322       .addImm(SrcSize); // Width
1323     I.eraseFromParent();
1324     return constrainSelectedInstRegOperands(*ExtI, TII, TRI, RBI);
1325   }
1326 
1327   if (SrcBank->getID() == AMDGPU::SGPRRegBankID && DstSize <= 64) {
1328     const TargetRegisterClass &SrcRC = InReg && DstSize > 32 ?
1329       AMDGPU::SReg_64RegClass : AMDGPU::SReg_32RegClass;
1330     if (!RBI.constrainGenericRegister(SrcReg, SrcRC, *MRI))
1331       return false;
1332 
1333     if (Signed && DstSize == 32 && (SrcSize == 8 || SrcSize == 16)) {
1334       const unsigned SextOpc = SrcSize == 8 ?
1335         AMDGPU::S_SEXT_I32_I8 : AMDGPU::S_SEXT_I32_I16;
1336       BuildMI(MBB, I, DL, TII.get(SextOpc), DstReg)
1337         .addReg(SrcReg);
1338       I.eraseFromParent();
1339       return RBI.constrainGenericRegister(DstReg, AMDGPU::SReg_32RegClass, *MRI);
1340     }
1341 
1342     const unsigned BFE64 = Signed ? AMDGPU::S_BFE_I64 : AMDGPU::S_BFE_U64;
1343     const unsigned BFE32 = Signed ? AMDGPU::S_BFE_I32 : AMDGPU::S_BFE_U32;
1344 
1345     // Scalar BFE is encoded as S1[5:0] = offset, S1[22:16]= width.
1346     if (DstSize > 32 && (SrcSize <= 32 || InReg)) {
1347       // We need a 64-bit register source, but the high bits don't matter.
1348       Register ExtReg = MRI->createVirtualRegister(&AMDGPU::SReg_64RegClass);
1349       Register UndefReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1350       unsigned SubReg = InReg ? AMDGPU::sub0 : 0;
1351 
1352       BuildMI(MBB, I, DL, TII.get(AMDGPU::IMPLICIT_DEF), UndefReg);
1353       BuildMI(MBB, I, DL, TII.get(AMDGPU::REG_SEQUENCE), ExtReg)
1354         .addReg(SrcReg, 0, SubReg)
1355         .addImm(AMDGPU::sub0)
1356         .addReg(UndefReg)
1357         .addImm(AMDGPU::sub1);
1358 
1359       BuildMI(MBB, I, DL, TII.get(BFE64), DstReg)
1360         .addReg(ExtReg)
1361         .addImm(SrcSize << 16);
1362 
1363       I.eraseFromParent();
1364       return RBI.constrainGenericRegister(DstReg, AMDGPU::SReg_64RegClass, *MRI);
1365     }
1366 
1367     unsigned Mask;
1368     if (!Signed && shouldUseAndMask(SrcSize, Mask)) {
1369       BuildMI(MBB, I, DL, TII.get(AMDGPU::S_AND_B32), DstReg)
1370         .addReg(SrcReg)
1371         .addImm(Mask);
1372     } else {
1373       BuildMI(MBB, I, DL, TII.get(BFE32), DstReg)
1374         .addReg(SrcReg)
1375         .addImm(SrcSize << 16);
1376     }
1377 
1378     I.eraseFromParent();
1379     return RBI.constrainGenericRegister(DstReg, AMDGPU::SReg_32RegClass, *MRI);
1380   }
1381 
1382   return false;
1383 }
1384 
1385 bool AMDGPUInstructionSelector::selectG_CONSTANT(MachineInstr &I) const {
1386   MachineBasicBlock *BB = I.getParent();
1387   MachineOperand &ImmOp = I.getOperand(1);
1388 
1389   // The AMDGPU backend only supports Imm operands and not CImm or FPImm.
1390   if (ImmOp.isFPImm()) {
1391     const APInt &Imm = ImmOp.getFPImm()->getValueAPF().bitcastToAPInt();
1392     ImmOp.ChangeToImmediate(Imm.getZExtValue());
1393   } else if (ImmOp.isCImm()) {
1394     ImmOp.ChangeToImmediate(ImmOp.getCImm()->getZExtValue());
1395   }
1396 
1397   Register DstReg = I.getOperand(0).getReg();
1398   unsigned Size;
1399   bool IsSgpr;
1400   const RegisterBank *RB = MRI->getRegBankOrNull(I.getOperand(0).getReg());
1401   if (RB) {
1402     IsSgpr = RB->getID() == AMDGPU::SGPRRegBankID;
1403     Size = MRI->getType(DstReg).getSizeInBits();
1404   } else {
1405     const TargetRegisterClass *RC = TRI.getRegClassForReg(*MRI, DstReg);
1406     IsSgpr = TRI.isSGPRClass(RC);
1407     Size = TRI.getRegSizeInBits(*RC);
1408   }
1409 
1410   if (Size != 32 && Size != 64)
1411     return false;
1412 
1413   unsigned Opcode = IsSgpr ? AMDGPU::S_MOV_B32 : AMDGPU::V_MOV_B32_e32;
1414   if (Size == 32) {
1415     I.setDesc(TII.get(Opcode));
1416     I.addImplicitDefUseOperands(*MF);
1417     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
1418   }
1419 
1420   const DebugLoc &DL = I.getDebugLoc();
1421 
1422   APInt Imm(Size, I.getOperand(1).getImm());
1423 
1424   MachineInstr *ResInst;
1425   if (IsSgpr && TII.isInlineConstant(Imm)) {
1426     ResInst = BuildMI(*BB, &I, DL, TII.get(AMDGPU::S_MOV_B64), DstReg)
1427       .addImm(I.getOperand(1).getImm());
1428   } else {
1429     const TargetRegisterClass *RC = IsSgpr ?
1430       &AMDGPU::SReg_32RegClass : &AMDGPU::VGPR_32RegClass;
1431     Register LoReg = MRI->createVirtualRegister(RC);
1432     Register HiReg = MRI->createVirtualRegister(RC);
1433 
1434     BuildMI(*BB, &I, DL, TII.get(Opcode), LoReg)
1435       .addImm(Imm.trunc(32).getZExtValue());
1436 
1437     BuildMI(*BB, &I, DL, TII.get(Opcode), HiReg)
1438       .addImm(Imm.ashr(32).getZExtValue());
1439 
1440     ResInst = BuildMI(*BB, &I, DL, TII.get(AMDGPU::REG_SEQUENCE), DstReg)
1441       .addReg(LoReg)
1442       .addImm(AMDGPU::sub0)
1443       .addReg(HiReg)
1444       .addImm(AMDGPU::sub1);
1445   }
1446 
1447   // We can't call constrainSelectedInstRegOperands here, because it doesn't
1448   // work for target independent opcodes
1449   I.eraseFromParent();
1450   const TargetRegisterClass *DstRC =
1451     TRI.getConstrainedRegClassForOperand(ResInst->getOperand(0), *MRI);
1452   if (!DstRC)
1453     return true;
1454   return RBI.constrainGenericRegister(DstReg, *DstRC, *MRI);
1455 }
1456 
1457 bool AMDGPUInstructionSelector::selectG_FNEG(MachineInstr &MI) const {
1458   // Only manually handle the f64 SGPR case.
1459   //
1460   // FIXME: This is a workaround for 2.5 different tablegen problems. Because
1461   // the bit ops theoretically have a second result due to the implicit def of
1462   // SCC, the GlobalISelEmitter is overly conservative and rejects it. Fixing
1463   // that is easy by disabling the check. The result works, but uses a
1464   // nonsensical sreg32orlds_and_sreg_1 regclass.
1465   //
1466   // The DAG emitter is more problematic, and incorrectly adds both S_XOR_B32 to
1467   // the variadic REG_SEQUENCE operands.
1468 
1469   Register Dst = MI.getOperand(0).getReg();
1470   const RegisterBank *DstRB = RBI.getRegBank(Dst, *MRI, TRI);
1471   if (DstRB->getID() != AMDGPU::SGPRRegBankID ||
1472       MRI->getType(Dst) != LLT::scalar(64))
1473     return false;
1474 
1475   Register Src = MI.getOperand(1).getReg();
1476   MachineInstr *Fabs = getOpcodeDef(TargetOpcode::G_FABS, Src, *MRI);
1477   if (Fabs)
1478     Src = Fabs->getOperand(1).getReg();
1479 
1480   if (!RBI.constrainGenericRegister(Src, AMDGPU::SReg_64RegClass, *MRI) ||
1481       !RBI.constrainGenericRegister(Dst, AMDGPU::SReg_64RegClass, *MRI))
1482     return false;
1483 
1484   MachineBasicBlock *BB = MI.getParent();
1485   const DebugLoc &DL = MI.getDebugLoc();
1486   Register LoReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1487   Register HiReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1488   Register ConstReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1489   Register OpReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
1490 
1491   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), LoReg)
1492     .addReg(Src, 0, AMDGPU::sub0);
1493   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), HiReg)
1494     .addReg(Src, 0, AMDGPU::sub1);
1495   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::S_MOV_B32), ConstReg)
1496     .addImm(0x80000000);
1497 
1498   // Set or toggle sign bit.
1499   unsigned Opc = Fabs ? AMDGPU::S_OR_B32 : AMDGPU::S_XOR_B32;
1500   BuildMI(*BB, &MI, DL, TII.get(Opc), OpReg)
1501     .addReg(HiReg)
1502     .addReg(ConstReg);
1503   BuildMI(*BB, &MI, DL, TII.get(AMDGPU::REG_SEQUENCE), Dst)
1504     .addReg(LoReg)
1505     .addImm(AMDGPU::sub0)
1506     .addReg(OpReg)
1507     .addImm(AMDGPU::sub1);
1508   MI.eraseFromParent();
1509   return true;
1510 }
1511 
1512 static bool isConstant(const MachineInstr &MI) {
1513   return MI.getOpcode() == TargetOpcode::G_CONSTANT;
1514 }
1515 
1516 void AMDGPUInstructionSelector::getAddrModeInfo(const MachineInstr &Load,
1517     const MachineRegisterInfo &MRI, SmallVectorImpl<GEPInfo> &AddrInfo) const {
1518 
1519   const MachineInstr *PtrMI = MRI.getUniqueVRegDef(Load.getOperand(1).getReg());
1520 
1521   assert(PtrMI);
1522 
1523   if (PtrMI->getOpcode() != TargetOpcode::G_PTR_ADD)
1524     return;
1525 
1526   GEPInfo GEPInfo(*PtrMI);
1527 
1528   for (unsigned i = 1; i != 3; ++i) {
1529     const MachineOperand &GEPOp = PtrMI->getOperand(i);
1530     const MachineInstr *OpDef = MRI.getUniqueVRegDef(GEPOp.getReg());
1531     assert(OpDef);
1532     if (i == 2 && isConstant(*OpDef)) {
1533       // TODO: Could handle constant base + variable offset, but a combine
1534       // probably should have commuted it.
1535       assert(GEPInfo.Imm == 0);
1536       GEPInfo.Imm = OpDef->getOperand(1).getCImm()->getSExtValue();
1537       continue;
1538     }
1539     const RegisterBank *OpBank = RBI.getRegBank(GEPOp.getReg(), MRI, TRI);
1540     if (OpBank->getID() == AMDGPU::SGPRRegBankID)
1541       GEPInfo.SgprParts.push_back(GEPOp.getReg());
1542     else
1543       GEPInfo.VgprParts.push_back(GEPOp.getReg());
1544   }
1545 
1546   AddrInfo.push_back(GEPInfo);
1547   getAddrModeInfo(*PtrMI, MRI, AddrInfo);
1548 }
1549 
1550 bool AMDGPUInstructionSelector::isInstrUniform(const MachineInstr &MI) const {
1551   if (!MI.hasOneMemOperand())
1552     return false;
1553 
1554   const MachineMemOperand *MMO = *MI.memoperands_begin();
1555   const Value *Ptr = MMO->getValue();
1556 
1557   // UndefValue means this is a load of a kernel input.  These are uniform.
1558   // Sometimes LDS instructions have constant pointers.
1559   // If Ptr is null, then that means this mem operand contains a
1560   // PseudoSourceValue like GOT.
1561   if (!Ptr || isa<UndefValue>(Ptr) || isa<Argument>(Ptr) ||
1562       isa<Constant>(Ptr) || isa<GlobalValue>(Ptr))
1563     return true;
1564 
1565   if (MMO->getAddrSpace() == AMDGPUAS::CONSTANT_ADDRESS_32BIT)
1566     return true;
1567 
1568   const Instruction *I = dyn_cast<Instruction>(Ptr);
1569   return I && I->getMetadata("amdgpu.uniform");
1570 }
1571 
1572 bool AMDGPUInstructionSelector::hasVgprParts(ArrayRef<GEPInfo> AddrInfo) const {
1573   for (const GEPInfo &GEPInfo : AddrInfo) {
1574     if (!GEPInfo.VgprParts.empty())
1575       return true;
1576   }
1577   return false;
1578 }
1579 
1580 void AMDGPUInstructionSelector::initM0(MachineInstr &I) const {
1581   MachineBasicBlock *BB = I.getParent();
1582 
1583   const LLT PtrTy = MRI->getType(I.getOperand(1).getReg());
1584   unsigned AS = PtrTy.getAddressSpace();
1585   if ((AS == AMDGPUAS::LOCAL_ADDRESS || AS == AMDGPUAS::REGION_ADDRESS) &&
1586       STI.ldsRequiresM0Init()) {
1587     // If DS instructions require M0 initializtion, insert it before selecting.
1588     BuildMI(*BB, &I, I.getDebugLoc(), TII.get(AMDGPU::S_MOV_B32), AMDGPU::M0)
1589       .addImm(-1);
1590   }
1591 }
1592 
1593 bool AMDGPUInstructionSelector::selectG_LOAD_ATOMICRMW(MachineInstr &I) const {
1594   initM0(I);
1595   return selectImpl(I, *CoverageInfo);
1596 }
1597 
1598 bool AMDGPUInstructionSelector::selectG_BRCOND(MachineInstr &I) const {
1599   MachineBasicBlock *BB = I.getParent();
1600   MachineOperand &CondOp = I.getOperand(0);
1601   Register CondReg = CondOp.getReg();
1602   const DebugLoc &DL = I.getDebugLoc();
1603 
1604   unsigned BrOpcode;
1605   Register CondPhysReg;
1606   const TargetRegisterClass *ConstrainRC;
1607 
1608   // In SelectionDAG, we inspect the IR block for uniformity metadata to decide
1609   // whether the branch is uniform when selecting the instruction. In
1610   // GlobalISel, we should push that decision into RegBankSelect. Assume for now
1611   // RegBankSelect knows what it's doing if the branch condition is scc, even
1612   // though it currently does not.
1613   if (!isVCC(CondReg, *MRI)) {
1614     if (MRI->getType(CondReg) != LLT::scalar(32))
1615       return false;
1616 
1617     CondPhysReg = AMDGPU::SCC;
1618     BrOpcode = AMDGPU::S_CBRANCH_SCC1;
1619     // FIXME: Hack for isSCC tests
1620     ConstrainRC = &AMDGPU::SGPR_32RegClass;
1621   } else {
1622     // FIXME: Do we have to insert an and with exec here, like in SelectionDAG?
1623     // We sort of know that a VCC producer based on the register bank, that ands
1624     // inactive lanes with 0. What if there was a logical operation with vcc
1625     // producers in different blocks/with different exec masks?
1626     // FIXME: Should scc->vcc copies and with exec?
1627     CondPhysReg = TRI.getVCC();
1628     BrOpcode = AMDGPU::S_CBRANCH_VCCNZ;
1629     ConstrainRC = TRI.getBoolRC();
1630   }
1631 
1632   if (!MRI->getRegClassOrNull(CondReg))
1633     MRI->setRegClass(CondReg, ConstrainRC);
1634 
1635   BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), CondPhysReg)
1636     .addReg(CondReg);
1637   BuildMI(*BB, &I, DL, TII.get(BrOpcode))
1638     .addMBB(I.getOperand(1).getMBB());
1639 
1640   I.eraseFromParent();
1641   return true;
1642 }
1643 
1644 bool AMDGPUInstructionSelector::selectG_FRAME_INDEX_GLOBAL_VALUE(
1645   MachineInstr &I) const {
1646   Register DstReg = I.getOperand(0).getReg();
1647   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
1648   const bool IsVGPR = DstRB->getID() == AMDGPU::VGPRRegBankID;
1649   I.setDesc(TII.get(IsVGPR ? AMDGPU::V_MOV_B32_e32 : AMDGPU::S_MOV_B32));
1650   if (IsVGPR)
1651     I.addOperand(*MF, MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
1652 
1653   return RBI.constrainGenericRegister(
1654     DstReg, IsVGPR ? AMDGPU::VGPR_32RegClass : AMDGPU::SReg_32RegClass, *MRI);
1655 }
1656 
1657 bool AMDGPUInstructionSelector::selectG_PTR_MASK(MachineInstr &I) const {
1658   uint64_t Align = I.getOperand(2).getImm();
1659   const uint64_t Mask = ~((UINT64_C(1) << Align) - 1);
1660 
1661   MachineBasicBlock *BB = I.getParent();
1662 
1663   Register DstReg = I.getOperand(0).getReg();
1664   Register SrcReg = I.getOperand(1).getReg();
1665 
1666   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
1667   const RegisterBank *SrcRB = RBI.getRegBank(SrcReg, *MRI, TRI);
1668   const bool IsVGPR = DstRB->getID() == AMDGPU::VGPRRegBankID;
1669   unsigned NewOpc = IsVGPR ? AMDGPU::V_AND_B32_e64 : AMDGPU::S_AND_B32;
1670   unsigned MovOpc = IsVGPR ? AMDGPU::V_MOV_B32_e32 : AMDGPU::S_MOV_B32;
1671   const TargetRegisterClass &RegRC
1672     = IsVGPR ? AMDGPU::VGPR_32RegClass : AMDGPU::SReg_32RegClass;
1673 
1674   LLT Ty = MRI->getType(DstReg);
1675 
1676   const TargetRegisterClass *DstRC = TRI.getRegClassForTypeOnBank(Ty, *DstRB,
1677                                                                   *MRI);
1678   const TargetRegisterClass *SrcRC = TRI.getRegClassForTypeOnBank(Ty, *SrcRB,
1679                                                                   *MRI);
1680   if (!RBI.constrainGenericRegister(DstReg, *DstRC, *MRI) ||
1681       !RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI))
1682     return false;
1683 
1684   const DebugLoc &DL = I.getDebugLoc();
1685   Register ImmReg = MRI->createVirtualRegister(&RegRC);
1686   BuildMI(*BB, &I, DL, TII.get(MovOpc), ImmReg)
1687     .addImm(Mask);
1688 
1689   if (Ty.getSizeInBits() == 32) {
1690     BuildMI(*BB, &I, DL, TII.get(NewOpc), DstReg)
1691       .addReg(SrcReg)
1692       .addReg(ImmReg);
1693     I.eraseFromParent();
1694     return true;
1695   }
1696 
1697   Register HiReg = MRI->createVirtualRegister(&RegRC);
1698   Register LoReg = MRI->createVirtualRegister(&RegRC);
1699   Register MaskLo = MRI->createVirtualRegister(&RegRC);
1700 
1701   BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), LoReg)
1702     .addReg(SrcReg, 0, AMDGPU::sub0);
1703   BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), HiReg)
1704     .addReg(SrcReg, 0, AMDGPU::sub1);
1705 
1706   BuildMI(*BB, &I, DL, TII.get(NewOpc), MaskLo)
1707     .addReg(LoReg)
1708     .addReg(ImmReg);
1709   BuildMI(*BB, &I, DL, TII.get(AMDGPU::REG_SEQUENCE), DstReg)
1710     .addReg(MaskLo)
1711     .addImm(AMDGPU::sub0)
1712     .addReg(HiReg)
1713     .addImm(AMDGPU::sub1);
1714   I.eraseFromParent();
1715   return true;
1716 }
1717 
1718 /// Return the register to use for the index value, and the subregister to use
1719 /// for the indirectly accessed register.
1720 static std::pair<Register, unsigned>
1721 computeIndirectRegIndex(MachineRegisterInfo &MRI,
1722                         const SIRegisterInfo &TRI,
1723                         const TargetRegisterClass *SuperRC,
1724                         Register IdxReg,
1725                         unsigned EltSize) {
1726   Register IdxBaseReg;
1727   int Offset;
1728   MachineInstr *Unused;
1729 
1730   std::tie(IdxBaseReg, Offset, Unused)
1731     = AMDGPU::getBaseWithConstantOffset(MRI, IdxReg);
1732   if (IdxBaseReg == AMDGPU::NoRegister) {
1733     // This will happen if the index is a known constant. This should ordinarily
1734     // be legalized out, but handle it as a register just in case.
1735     assert(Offset == 0);
1736     IdxBaseReg = IdxReg;
1737   }
1738 
1739   ArrayRef<int16_t> SubRegs = TRI.getRegSplitParts(SuperRC, EltSize);
1740 
1741   // Skip out of bounds offsets, or else we would end up using an undefined
1742   // register.
1743   if (static_cast<unsigned>(Offset) >= SubRegs.size())
1744     return std::make_pair(IdxReg, SubRegs[0]);
1745   return std::make_pair(IdxBaseReg, SubRegs[Offset]);
1746 }
1747 
1748 bool AMDGPUInstructionSelector::selectG_EXTRACT_VECTOR_ELT(
1749   MachineInstr &MI) const {
1750   Register DstReg = MI.getOperand(0).getReg();
1751   Register SrcReg = MI.getOperand(1).getReg();
1752   Register IdxReg = MI.getOperand(2).getReg();
1753 
1754   LLT DstTy = MRI->getType(DstReg);
1755   LLT SrcTy = MRI->getType(SrcReg);
1756 
1757   const RegisterBank *DstRB = RBI.getRegBank(DstReg, *MRI, TRI);
1758   const RegisterBank *SrcRB = RBI.getRegBank(SrcReg, *MRI, TRI);
1759   const RegisterBank *IdxRB = RBI.getRegBank(IdxReg, *MRI, TRI);
1760 
1761   // The index must be scalar. If it wasn't RegBankSelect should have moved this
1762   // into a waterfall loop.
1763   if (IdxRB->getID() != AMDGPU::SGPRRegBankID)
1764     return false;
1765 
1766   const TargetRegisterClass *SrcRC = TRI.getRegClassForTypeOnBank(SrcTy, *SrcRB,
1767                                                                   *MRI);
1768   const TargetRegisterClass *DstRC = TRI.getRegClassForTypeOnBank(DstTy, *DstRB,
1769                                                                   *MRI);
1770   if (!RBI.constrainGenericRegister(SrcReg, *SrcRC, *MRI) ||
1771       !RBI.constrainGenericRegister(DstReg, *DstRC, *MRI) ||
1772       !RBI.constrainGenericRegister(IdxReg, AMDGPU::SReg_32RegClass, *MRI))
1773     return false;
1774 
1775   MachineBasicBlock *BB = MI.getParent();
1776   const DebugLoc &DL = MI.getDebugLoc();
1777   const bool Is64 = DstTy.getSizeInBits() == 64;
1778 
1779   unsigned SubReg;
1780   std::tie(IdxReg, SubReg) = computeIndirectRegIndex(*MRI, TRI, SrcRC, IdxReg,
1781                                                      DstTy.getSizeInBits() / 8);
1782 
1783   if (SrcRB->getID() == AMDGPU::SGPRRegBankID) {
1784     if (DstTy.getSizeInBits() != 32 && !Is64)
1785       return false;
1786 
1787     BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1788       .addReg(IdxReg);
1789 
1790     unsigned Opc = Is64 ? AMDGPU::S_MOVRELS_B64 : AMDGPU::S_MOVRELS_B32;
1791     BuildMI(*BB, &MI, DL, TII.get(Opc), DstReg)
1792       .addReg(SrcReg, 0, SubReg)
1793       .addReg(SrcReg, RegState::Implicit);
1794     MI.eraseFromParent();
1795     return true;
1796   }
1797 
1798   if (SrcRB->getID() != AMDGPU::VGPRRegBankID || DstTy.getSizeInBits() != 32)
1799     return false;
1800 
1801   if (!STI.useVGPRIndexMode()) {
1802     BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1803       .addReg(IdxReg);
1804     BuildMI(*BB, &MI, DL, TII.get(AMDGPU::V_MOVRELS_B32_e32), DstReg)
1805       .addReg(SrcReg, RegState::Undef, SubReg)
1806       .addReg(SrcReg, RegState::Implicit);
1807     MI.eraseFromParent();
1808     return true;
1809   }
1810 
1811   BuildMI(*BB, MI, DL, TII.get(AMDGPU::S_SET_GPR_IDX_ON))
1812     .addReg(IdxReg)
1813     .addImm(AMDGPU::VGPRIndexMode::SRC0_ENABLE);
1814   BuildMI(*BB, MI, DL, TII.get(AMDGPU::V_MOV_B32_e32), DstReg)
1815     .addReg(SrcReg, RegState::Undef, SubReg)
1816     .addReg(SrcReg, RegState::Implicit)
1817     .addReg(AMDGPU::M0, RegState::Implicit);
1818   BuildMI(*BB, MI, DL, TII.get(AMDGPU::S_SET_GPR_IDX_OFF));
1819 
1820   MI.eraseFromParent();
1821   return true;
1822 }
1823 
1824 // TODO: Fold insert_vector_elt (extract_vector_elt) into movrelsd
1825 bool AMDGPUInstructionSelector::selectG_INSERT_VECTOR_ELT(
1826   MachineInstr &MI) const {
1827   Register DstReg = MI.getOperand(0).getReg();
1828   Register VecReg = MI.getOperand(1).getReg();
1829   Register ValReg = MI.getOperand(2).getReg();
1830   Register IdxReg = MI.getOperand(3).getReg();
1831 
1832   LLT VecTy = MRI->getType(DstReg);
1833   LLT ValTy = MRI->getType(ValReg);
1834   unsigned VecSize = VecTy.getSizeInBits();
1835   unsigned ValSize = ValTy.getSizeInBits();
1836 
1837   const RegisterBank *VecRB = RBI.getRegBank(VecReg, *MRI, TRI);
1838   const RegisterBank *ValRB = RBI.getRegBank(ValReg, *MRI, TRI);
1839   const RegisterBank *IdxRB = RBI.getRegBank(IdxReg, *MRI, TRI);
1840 
1841   assert(VecTy.getElementType() == ValTy);
1842 
1843   // The index must be scalar. If it wasn't RegBankSelect should have moved this
1844   // into a waterfall loop.
1845   if (IdxRB->getID() != AMDGPU::SGPRRegBankID)
1846     return false;
1847 
1848   const TargetRegisterClass *VecRC = TRI.getRegClassForTypeOnBank(VecTy, *VecRB,
1849                                                                   *MRI);
1850   const TargetRegisterClass *ValRC = TRI.getRegClassForTypeOnBank(ValTy, *ValRB,
1851                                                                   *MRI);
1852 
1853   if (!RBI.constrainGenericRegister(VecReg, *VecRC, *MRI) ||
1854       !RBI.constrainGenericRegister(DstReg, *VecRC, *MRI) ||
1855       !RBI.constrainGenericRegister(ValReg, *ValRC, *MRI) ||
1856       !RBI.constrainGenericRegister(IdxReg, AMDGPU::SReg_32RegClass, *MRI))
1857     return false;
1858 
1859   if (VecRB->getID() == AMDGPU::VGPRRegBankID && ValSize != 32)
1860     return false;
1861 
1862   unsigned SubReg;
1863   std::tie(IdxReg, SubReg) = computeIndirectRegIndex(*MRI, TRI, VecRC, IdxReg,
1864                                                      ValSize / 8);
1865 
1866   const bool IndexMode = VecRB->getID() == AMDGPU::VGPRRegBankID &&
1867                          STI.useVGPRIndexMode();
1868 
1869   MachineBasicBlock *BB = MI.getParent();
1870   const DebugLoc &DL = MI.getDebugLoc();
1871 
1872   if (IndexMode) {
1873     BuildMI(*BB, MI, DL, TII.get(AMDGPU::S_SET_GPR_IDX_ON))
1874       .addReg(IdxReg)
1875       .addImm(AMDGPU::VGPRIndexMode::DST_ENABLE);
1876   } else {
1877     BuildMI(*BB, &MI, DL, TII.get(AMDGPU::COPY), AMDGPU::M0)
1878       .addReg(IdxReg);
1879   }
1880 
1881   const MCInstrDesc &RegWriteOp
1882     = TII.getIndirectRegWritePseudo(VecSize, ValSize,
1883                                     VecRB->getID() == AMDGPU::SGPRRegBankID);
1884   BuildMI(*BB, MI, DL, RegWriteOp, DstReg)
1885     .addReg(VecReg)
1886     .addReg(ValReg)
1887     .addImm(SubReg);
1888 
1889   if (IndexMode)
1890     BuildMI(*BB, MI, DL, TII.get(AMDGPU::S_SET_GPR_IDX_OFF));
1891 
1892   MI.eraseFromParent();
1893   return true;
1894 }
1895 
1896 bool AMDGPUInstructionSelector::select(MachineInstr &I) {
1897   if (I.isPHI())
1898     return selectPHI(I);
1899 
1900   if (!I.isPreISelOpcode()) {
1901     if (I.isCopy())
1902       return selectCOPY(I);
1903     return true;
1904   }
1905 
1906   switch (I.getOpcode()) {
1907   case TargetOpcode::G_AND:
1908   case TargetOpcode::G_OR:
1909   case TargetOpcode::G_XOR:
1910     if (selectG_AND_OR_XOR(I))
1911       return true;
1912     return selectImpl(I, *CoverageInfo);
1913   case TargetOpcode::G_ADD:
1914   case TargetOpcode::G_SUB:
1915     if (selectImpl(I, *CoverageInfo))
1916       return true;
1917     return selectG_ADD_SUB(I);
1918   case TargetOpcode::G_UADDO:
1919   case TargetOpcode::G_USUBO:
1920   case TargetOpcode::G_UADDE:
1921   case TargetOpcode::G_USUBE:
1922     return selectG_UADDO_USUBO_UADDE_USUBE(I);
1923   case TargetOpcode::G_INTTOPTR:
1924   case TargetOpcode::G_BITCAST:
1925   case TargetOpcode::G_PTRTOINT:
1926     return selectCOPY(I);
1927   case TargetOpcode::G_CONSTANT:
1928   case TargetOpcode::G_FCONSTANT:
1929     return selectG_CONSTANT(I);
1930   case TargetOpcode::G_FNEG:
1931     if (selectImpl(I, *CoverageInfo))
1932       return true;
1933     return selectG_FNEG(I);
1934   case TargetOpcode::G_EXTRACT:
1935     return selectG_EXTRACT(I);
1936   case TargetOpcode::G_MERGE_VALUES:
1937   case TargetOpcode::G_BUILD_VECTOR:
1938   case TargetOpcode::G_CONCAT_VECTORS:
1939     return selectG_MERGE_VALUES(I);
1940   case TargetOpcode::G_UNMERGE_VALUES:
1941     return selectG_UNMERGE_VALUES(I);
1942   case TargetOpcode::G_PTR_ADD:
1943     return selectG_PTR_ADD(I);
1944   case TargetOpcode::G_IMPLICIT_DEF:
1945     return selectG_IMPLICIT_DEF(I);
1946   case TargetOpcode::G_INSERT:
1947     return selectG_INSERT(I);
1948   case TargetOpcode::G_INTRINSIC:
1949     return selectG_INTRINSIC(I);
1950   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
1951     return selectG_INTRINSIC_W_SIDE_EFFECTS(I);
1952   case TargetOpcode::G_ICMP:
1953     if (selectG_ICMP(I))
1954       return true;
1955     return selectImpl(I, *CoverageInfo);
1956   case TargetOpcode::G_LOAD:
1957   case TargetOpcode::G_ATOMIC_CMPXCHG:
1958   case TargetOpcode::G_ATOMICRMW_XCHG:
1959   case TargetOpcode::G_ATOMICRMW_ADD:
1960   case TargetOpcode::G_ATOMICRMW_SUB:
1961   case TargetOpcode::G_ATOMICRMW_AND:
1962   case TargetOpcode::G_ATOMICRMW_OR:
1963   case TargetOpcode::G_ATOMICRMW_XOR:
1964   case TargetOpcode::G_ATOMICRMW_MIN:
1965   case TargetOpcode::G_ATOMICRMW_MAX:
1966   case TargetOpcode::G_ATOMICRMW_UMIN:
1967   case TargetOpcode::G_ATOMICRMW_UMAX:
1968   case TargetOpcode::G_ATOMICRMW_FADD:
1969     return selectG_LOAD_ATOMICRMW(I);
1970   case TargetOpcode::G_SELECT:
1971     return selectG_SELECT(I);
1972   case TargetOpcode::G_STORE:
1973     return selectG_STORE(I);
1974   case TargetOpcode::G_TRUNC:
1975     return selectG_TRUNC(I);
1976   case TargetOpcode::G_SEXT:
1977   case TargetOpcode::G_ZEXT:
1978   case TargetOpcode::G_ANYEXT:
1979   case TargetOpcode::G_SEXT_INREG:
1980     if (selectImpl(I, *CoverageInfo))
1981       return true;
1982     return selectG_SZA_EXT(I);
1983   case TargetOpcode::G_BRCOND:
1984     return selectG_BRCOND(I);
1985   case TargetOpcode::G_FRAME_INDEX:
1986   case TargetOpcode::G_GLOBAL_VALUE:
1987     return selectG_FRAME_INDEX_GLOBAL_VALUE(I);
1988   case TargetOpcode::G_PTR_MASK:
1989     return selectG_PTR_MASK(I);
1990   case TargetOpcode::G_EXTRACT_VECTOR_ELT:
1991     return selectG_EXTRACT_VECTOR_ELT(I);
1992   case TargetOpcode::G_INSERT_VECTOR_ELT:
1993     return selectG_INSERT_VECTOR_ELT(I);
1994   case AMDGPU::G_AMDGPU_ATOMIC_INC:
1995   case AMDGPU::G_AMDGPU_ATOMIC_DEC:
1996     initM0(I);
1997     return selectImpl(I, *CoverageInfo);
1998   default:
1999     return selectImpl(I, *CoverageInfo);
2000   }
2001   return false;
2002 }
2003 
2004 InstructionSelector::ComplexRendererFns
2005 AMDGPUInstructionSelector::selectVCSRC(MachineOperand &Root) const {
2006   return {{
2007       [=](MachineInstrBuilder &MIB) { MIB.add(Root); }
2008   }};
2009 
2010 }
2011 
2012 std::pair<Register, unsigned>
2013 AMDGPUInstructionSelector::selectVOP3ModsImpl(
2014   Register Src) const {
2015   unsigned Mods = 0;
2016   MachineInstr *MI = getDefIgnoringCopies(Src, *MRI);
2017 
2018   if (MI && MI->getOpcode() == AMDGPU::G_FNEG) {
2019     Src = MI->getOperand(1).getReg();
2020     Mods |= SISrcMods::NEG;
2021     MI = getDefIgnoringCopies(Src, *MRI);
2022   }
2023 
2024   if (MI && MI->getOpcode() == AMDGPU::G_FABS) {
2025     Src = MI->getOperand(1).getReg();
2026     Mods |= SISrcMods::ABS;
2027   }
2028 
2029   return std::make_pair(Src, Mods);
2030 }
2031 
2032 ///
2033 /// This will select either an SGPR or VGPR operand and will save us from
2034 /// having to write an extra tablegen pattern.
2035 InstructionSelector::ComplexRendererFns
2036 AMDGPUInstructionSelector::selectVSRC0(MachineOperand &Root) const {
2037   return {{
2038       [=](MachineInstrBuilder &MIB) { MIB.add(Root); }
2039   }};
2040 }
2041 
2042 InstructionSelector::ComplexRendererFns
2043 AMDGPUInstructionSelector::selectVOP3Mods0(MachineOperand &Root) const {
2044   Register Src;
2045   unsigned Mods;
2046   std::tie(Src, Mods) = selectVOP3ModsImpl(Root.getReg());
2047 
2048   return {{
2049       [=](MachineInstrBuilder &MIB) { MIB.addReg(Src); },
2050       [=](MachineInstrBuilder &MIB) { MIB.addImm(Mods); }, // src0_mods
2051       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); },    // clamp
2052       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }     // omod
2053   }};
2054 }
2055 
2056 InstructionSelector::ComplexRendererFns
2057 AMDGPUInstructionSelector::selectVOP3OMods(MachineOperand &Root) const {
2058   return {{
2059       [=](MachineInstrBuilder &MIB) { MIB.add(Root); },
2060       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }, // clamp
2061       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }  // omod
2062   }};
2063 }
2064 
2065 InstructionSelector::ComplexRendererFns
2066 AMDGPUInstructionSelector::selectVOP3Mods(MachineOperand &Root) const {
2067   Register Src;
2068   unsigned Mods;
2069   std::tie(Src, Mods) = selectVOP3ModsImpl(Root.getReg());
2070 
2071   return {{
2072       [=](MachineInstrBuilder &MIB) { MIB.addReg(Src); },
2073       [=](MachineInstrBuilder &MIB) { MIB.addImm(Mods); }  // src_mods
2074   }};
2075 }
2076 
2077 InstructionSelector::ComplexRendererFns
2078 AMDGPUInstructionSelector::selectVOP3NoMods(MachineOperand &Root) const {
2079   Register Reg = Root.getReg();
2080   const MachineInstr *Def = getDefIgnoringCopies(Reg, *MRI);
2081   if (Def && (Def->getOpcode() == AMDGPU::G_FNEG ||
2082               Def->getOpcode() == AMDGPU::G_FABS))
2083     return {};
2084   return {{
2085       [=](MachineInstrBuilder &MIB) { MIB.addReg(Reg); },
2086   }};
2087 }
2088 
2089 InstructionSelector::ComplexRendererFns
2090 AMDGPUInstructionSelector::selectVOP3Mods_nnan(MachineOperand &Root) const {
2091   Register Src;
2092   unsigned Mods;
2093   std::tie(Src, Mods) = selectVOP3ModsImpl(Root.getReg());
2094   if (!TM.Options.NoNaNsFPMath && !isKnownNeverNaN(Src, *MRI))
2095     return None;
2096 
2097   return {{
2098       [=](MachineInstrBuilder &MIB) { MIB.addReg(Src); },
2099       [=](MachineInstrBuilder &MIB) { MIB.addImm(Mods); }  // src_mods
2100   }};
2101 }
2102 
2103 InstructionSelector::ComplexRendererFns
2104 AMDGPUInstructionSelector::selectVOP3OpSelMods0(MachineOperand &Root) const {
2105   // FIXME: Handle clamp and op_sel
2106   return {{
2107       [=](MachineInstrBuilder &MIB) { MIB.addReg(Root.getReg()); },
2108       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }, // src_mods
2109       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }  // clamp
2110   }};
2111 }
2112 
2113 InstructionSelector::ComplexRendererFns
2114 AMDGPUInstructionSelector::selectVOP3OpSelMods(MachineOperand &Root) const {
2115   // FIXME: Handle op_sel
2116   return {{
2117       [=](MachineInstrBuilder &MIB) { MIB.addReg(Root.getReg()); },
2118       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); } // src_mods
2119   }};
2120 }
2121 
2122 InstructionSelector::ComplexRendererFns
2123 AMDGPUInstructionSelector::selectSmrdImm(MachineOperand &Root) const {
2124   SmallVector<GEPInfo, 4> AddrInfo;
2125   getAddrModeInfo(*Root.getParent(), *MRI, AddrInfo);
2126 
2127   if (AddrInfo.empty() || AddrInfo[0].SgprParts.size() != 1)
2128     return None;
2129 
2130   const GEPInfo &GEPInfo = AddrInfo[0];
2131   Optional<int64_t> EncodedImm = AMDGPU::getSMRDEncodedOffset(STI, GEPInfo.Imm);
2132   if (!EncodedImm)
2133     return None;
2134 
2135   unsigned PtrReg = GEPInfo.SgprParts[0];
2136   return {{
2137     [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrReg); },
2138     [=](MachineInstrBuilder &MIB) { MIB.addImm(*EncodedImm); }
2139   }};
2140 }
2141 
2142 InstructionSelector::ComplexRendererFns
2143 AMDGPUInstructionSelector::selectSmrdImm32(MachineOperand &Root) const {
2144   SmallVector<GEPInfo, 4> AddrInfo;
2145   getAddrModeInfo(*Root.getParent(), *MRI, AddrInfo);
2146 
2147   if (AddrInfo.empty() || AddrInfo[0].SgprParts.size() != 1)
2148     return None;
2149 
2150   const GEPInfo &GEPInfo = AddrInfo[0];
2151   unsigned PtrReg = GEPInfo.SgprParts[0];
2152   Optional<int64_t> EncodedImm =
2153       AMDGPU::getSMRDEncodedLiteralOffset32(STI, GEPInfo.Imm);
2154   if (!EncodedImm)
2155     return None;
2156 
2157   return {{
2158     [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrReg); },
2159     [=](MachineInstrBuilder &MIB) { MIB.addImm(*EncodedImm); }
2160   }};
2161 }
2162 
2163 InstructionSelector::ComplexRendererFns
2164 AMDGPUInstructionSelector::selectSmrdSgpr(MachineOperand &Root) const {
2165   MachineInstr *MI = Root.getParent();
2166   MachineBasicBlock *MBB = MI->getParent();
2167 
2168   SmallVector<GEPInfo, 4> AddrInfo;
2169   getAddrModeInfo(*MI, *MRI, AddrInfo);
2170 
2171   // FIXME: We should shrink the GEP if the offset is known to be <= 32-bits,
2172   // then we can select all ptr + 32-bit offsets not just immediate offsets.
2173   if (AddrInfo.empty() || AddrInfo[0].SgprParts.size() != 1)
2174     return None;
2175 
2176   const GEPInfo &GEPInfo = AddrInfo[0];
2177   if (!GEPInfo.Imm || !isUInt<32>(GEPInfo.Imm))
2178     return None;
2179 
2180   // If we make it this far we have a load with an 32-bit immediate offset.
2181   // It is OK to select this using a sgpr offset, because we have already
2182   // failed trying to select this load into one of the _IMM variants since
2183   // the _IMM Patterns are considered before the _SGPR patterns.
2184   unsigned PtrReg = GEPInfo.SgprParts[0];
2185   Register OffsetReg = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2186   BuildMI(*MBB, MI, MI->getDebugLoc(), TII.get(AMDGPU::S_MOV_B32), OffsetReg)
2187           .addImm(GEPInfo.Imm);
2188   return {{
2189     [=](MachineInstrBuilder &MIB) { MIB.addReg(PtrReg); },
2190     [=](MachineInstrBuilder &MIB) { MIB.addReg(OffsetReg); }
2191   }};
2192 }
2193 
2194 template <bool Signed>
2195 InstructionSelector::ComplexRendererFns
2196 AMDGPUInstructionSelector::selectFlatOffsetImpl(MachineOperand &Root) const {
2197   MachineInstr *MI = Root.getParent();
2198 
2199   InstructionSelector::ComplexRendererFns Default = {{
2200       [=](MachineInstrBuilder &MIB) { MIB.addReg(Root.getReg()); },
2201       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); },  // offset
2202       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }  // slc
2203     }};
2204 
2205   if (!STI.hasFlatInstOffsets())
2206     return Default;
2207 
2208   const MachineInstr *OpDef = MRI->getVRegDef(Root.getReg());
2209   if (!OpDef || OpDef->getOpcode() != AMDGPU::G_PTR_ADD)
2210     return Default;
2211 
2212   Optional<int64_t> Offset =
2213     getConstantVRegVal(OpDef->getOperand(2).getReg(), *MRI);
2214   if (!Offset.hasValue())
2215     return Default;
2216 
2217   unsigned AddrSpace = (*MI->memoperands_begin())->getAddrSpace();
2218   if (!TII.isLegalFLATOffset(Offset.getValue(), AddrSpace, Signed))
2219     return Default;
2220 
2221   Register BasePtr = OpDef->getOperand(1).getReg();
2222 
2223   return {{
2224       [=](MachineInstrBuilder &MIB) { MIB.addReg(BasePtr); },
2225       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset.getValue()); },
2226       [=](MachineInstrBuilder &MIB) { MIB.addImm(0); }  // slc
2227     }};
2228 }
2229 
2230 InstructionSelector::ComplexRendererFns
2231 AMDGPUInstructionSelector::selectFlatOffset(MachineOperand &Root) const {
2232   return selectFlatOffsetImpl<false>(Root);
2233 }
2234 
2235 InstructionSelector::ComplexRendererFns
2236 AMDGPUInstructionSelector::selectFlatOffsetSigned(MachineOperand &Root) const {
2237   return selectFlatOffsetImpl<true>(Root);
2238 }
2239 
2240 static bool isStackPtrRelative(const MachinePointerInfo &PtrInfo) {
2241   auto PSV = PtrInfo.V.dyn_cast<const PseudoSourceValue *>();
2242   return PSV && PSV->isStack();
2243 }
2244 
2245 InstructionSelector::ComplexRendererFns
2246 AMDGPUInstructionSelector::selectMUBUFScratchOffen(MachineOperand &Root) const {
2247   MachineInstr *MI = Root.getParent();
2248   MachineBasicBlock *MBB = MI->getParent();
2249   MachineFunction *MF = MBB->getParent();
2250   const SIMachineFunctionInfo *Info = MF->getInfo<SIMachineFunctionInfo>();
2251 
2252   int64_t Offset = 0;
2253   if (mi_match(Root.getReg(), *MRI, m_ICst(Offset))) {
2254     Register HighBits = MRI->createVirtualRegister(&AMDGPU::VGPR_32RegClass);
2255 
2256     // TODO: Should this be inside the render function? The iterator seems to
2257     // move.
2258     BuildMI(*MBB, MI, MI->getDebugLoc(), TII.get(AMDGPU::V_MOV_B32_e32),
2259             HighBits)
2260       .addImm(Offset & ~4095);
2261 
2262     return {{[=](MachineInstrBuilder &MIB) { // rsrc
2263                MIB.addReg(Info->getScratchRSrcReg());
2264              },
2265              [=](MachineInstrBuilder &MIB) { // vaddr
2266                MIB.addReg(HighBits);
2267              },
2268              [=](MachineInstrBuilder &MIB) { // soffset
2269                const MachineMemOperand *MMO = *MI->memoperands_begin();
2270                const MachinePointerInfo &PtrInfo = MMO->getPointerInfo();
2271 
2272                Register SOffsetReg = isStackPtrRelative(PtrInfo)
2273                                          ? Info->getStackPtrOffsetReg()
2274                                          : Info->getScratchWaveOffsetReg();
2275                MIB.addReg(SOffsetReg);
2276              },
2277              [=](MachineInstrBuilder &MIB) { // offset
2278                MIB.addImm(Offset & 4095);
2279              }}};
2280   }
2281 
2282   assert(Offset == 0);
2283 
2284   // Try to fold a frame index directly into the MUBUF vaddr field, and any
2285   // offsets.
2286   Optional<int> FI;
2287   Register VAddr = Root.getReg();
2288   if (const MachineInstr *RootDef = MRI->getVRegDef(Root.getReg())) {
2289     if (isBaseWithConstantOffset(Root, *MRI)) {
2290       const MachineOperand &LHS = RootDef->getOperand(1);
2291       const MachineOperand &RHS = RootDef->getOperand(2);
2292       const MachineInstr *LHSDef = MRI->getVRegDef(LHS.getReg());
2293       const MachineInstr *RHSDef = MRI->getVRegDef(RHS.getReg());
2294       if (LHSDef && RHSDef) {
2295         int64_t PossibleOffset =
2296             RHSDef->getOperand(1).getCImm()->getSExtValue();
2297         if (SIInstrInfo::isLegalMUBUFImmOffset(PossibleOffset) &&
2298             (!STI.privateMemoryResourceIsRangeChecked() ||
2299              KnownBits->signBitIsZero(LHS.getReg()))) {
2300           if (LHSDef->getOpcode() == AMDGPU::G_FRAME_INDEX)
2301             FI = LHSDef->getOperand(1).getIndex();
2302           else
2303             VAddr = LHS.getReg();
2304           Offset = PossibleOffset;
2305         }
2306       }
2307     } else if (RootDef->getOpcode() == AMDGPU::G_FRAME_INDEX) {
2308       FI = RootDef->getOperand(1).getIndex();
2309     }
2310   }
2311 
2312   // If we don't know this private access is a local stack object, it needs to
2313   // be relative to the entry point's scratch wave offset register.
2314   // TODO: Should split large offsets that don't fit like above.
2315   // TODO: Don't use scratch wave offset just because the offset didn't fit.
2316   Register SOffset = FI.hasValue() ? Info->getStackPtrOffsetReg()
2317                                    : Info->getScratchWaveOffsetReg();
2318 
2319   return {{[=](MachineInstrBuilder &MIB) { // rsrc
2320              MIB.addReg(Info->getScratchRSrcReg());
2321            },
2322            [=](MachineInstrBuilder &MIB) { // vaddr
2323              if (FI.hasValue())
2324                MIB.addFrameIndex(FI.getValue());
2325              else
2326                MIB.addReg(VAddr);
2327            },
2328            [=](MachineInstrBuilder &MIB) { // soffset
2329              MIB.addReg(SOffset);
2330            },
2331            [=](MachineInstrBuilder &MIB) { // offset
2332              MIB.addImm(Offset);
2333            }}};
2334 }
2335 
2336 bool AMDGPUInstructionSelector::isDSOffsetLegal(Register Base,
2337                                                 int64_t Offset,
2338                                                 unsigned OffsetBits) const {
2339   if ((OffsetBits == 16 && !isUInt<16>(Offset)) ||
2340       (OffsetBits == 8 && !isUInt<8>(Offset)))
2341     return false;
2342 
2343   if (STI.hasUsableDSOffset() || STI.unsafeDSOffsetFoldingEnabled())
2344     return true;
2345 
2346   // On Southern Islands instruction with a negative base value and an offset
2347   // don't seem to work.
2348   return KnownBits->signBitIsZero(Base);
2349 }
2350 
2351 InstructionSelector::ComplexRendererFns
2352 AMDGPUInstructionSelector::selectMUBUFScratchOffset(
2353     MachineOperand &Root) const {
2354   MachineInstr *MI = Root.getParent();
2355   MachineBasicBlock *MBB = MI->getParent();
2356 
2357   int64_t Offset = 0;
2358   if (!mi_match(Root.getReg(), *MRI, m_ICst(Offset)) ||
2359       !SIInstrInfo::isLegalMUBUFImmOffset(Offset))
2360     return {};
2361 
2362   const MachineFunction *MF = MBB->getParent();
2363   const SIMachineFunctionInfo *Info = MF->getInfo<SIMachineFunctionInfo>();
2364   const MachineMemOperand *MMO = *MI->memoperands_begin();
2365   const MachinePointerInfo &PtrInfo = MMO->getPointerInfo();
2366 
2367   Register SOffsetReg = isStackPtrRelative(PtrInfo)
2368                             ? Info->getStackPtrOffsetReg()
2369                             : Info->getScratchWaveOffsetReg();
2370   return {{
2371       [=](MachineInstrBuilder &MIB) {
2372         MIB.addReg(Info->getScratchRSrcReg());
2373       },                                                         // rsrc
2374       [=](MachineInstrBuilder &MIB) { MIB.addReg(SOffsetReg); }, // soffset
2375       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); }      // offset
2376   }};
2377 }
2378 
2379 std::pair<Register, unsigned>
2380 AMDGPUInstructionSelector::selectDS1Addr1OffsetImpl(MachineOperand &Root) const {
2381   const MachineInstr *RootDef = MRI->getVRegDef(Root.getReg());
2382   if (!RootDef)
2383     return std::make_pair(Root.getReg(), 0);
2384 
2385   int64_t ConstAddr = 0;
2386 
2387   Register PtrBase;
2388   int64_t Offset;
2389   std::tie(PtrBase, Offset) =
2390     getPtrBaseWithConstantOffset(Root.getReg(), *MRI);
2391 
2392   if (Offset) {
2393     if (isDSOffsetLegal(PtrBase, Offset, 16)) {
2394       // (add n0, c0)
2395       return std::make_pair(PtrBase, Offset);
2396     }
2397   } else if (RootDef->getOpcode() == AMDGPU::G_SUB) {
2398     // TODO
2399 
2400 
2401   } else if (mi_match(Root.getReg(), *MRI, m_ICst(ConstAddr))) {
2402     // TODO
2403 
2404   }
2405 
2406   return std::make_pair(Root.getReg(), 0);
2407 }
2408 
2409 InstructionSelector::ComplexRendererFns
2410 AMDGPUInstructionSelector::selectDS1Addr1Offset(MachineOperand &Root) const {
2411   Register Reg;
2412   unsigned Offset;
2413   std::tie(Reg, Offset) = selectDS1Addr1OffsetImpl(Root);
2414   return {{
2415       [=](MachineInstrBuilder &MIB) { MIB.addReg(Reg); },
2416       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); }
2417     }};
2418 }
2419 
2420 InstructionSelector::ComplexRendererFns
2421 AMDGPUInstructionSelector::selectDS64Bit4ByteAligned(MachineOperand &Root) const {
2422   Register Reg;
2423   unsigned Offset;
2424   std::tie(Reg, Offset) = selectDS64Bit4ByteAlignedImpl(Root);
2425   return {{
2426       [=](MachineInstrBuilder &MIB) { MIB.addReg(Reg); },
2427       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); },
2428       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset+1); }
2429     }};
2430 }
2431 
2432 std::pair<Register, unsigned>
2433 AMDGPUInstructionSelector::selectDS64Bit4ByteAlignedImpl(MachineOperand &Root) const {
2434   const MachineInstr *RootDef = MRI->getVRegDef(Root.getReg());
2435   if (!RootDef)
2436     return std::make_pair(Root.getReg(), 0);
2437 
2438   int64_t ConstAddr = 0;
2439 
2440   Register PtrBase;
2441   int64_t Offset;
2442   std::tie(PtrBase, Offset) =
2443     getPtrBaseWithConstantOffset(Root.getReg(), *MRI);
2444 
2445   if (Offset) {
2446     int64_t DWordOffset0 = Offset / 4;
2447     int64_t DWordOffset1 = DWordOffset0 + 1;
2448     if (isDSOffsetLegal(PtrBase, DWordOffset1, 8)) {
2449       // (add n0, c0)
2450       return std::make_pair(PtrBase, DWordOffset0);
2451     }
2452   } else if (RootDef->getOpcode() == AMDGPU::G_SUB) {
2453     // TODO
2454 
2455   } else if (mi_match(Root.getReg(), *MRI, m_ICst(ConstAddr))) {
2456     // TODO
2457 
2458   }
2459 
2460   return std::make_pair(Root.getReg(), 0);
2461 }
2462 
2463 /// If \p Root is a G_PTR_ADD with a G_CONSTANT on the right hand side, return
2464 /// the base value with the constant offset. There may be intervening copies
2465 /// between \p Root and the identified constant. Returns \p Root, 0 if this does
2466 /// not match the pattern.
2467 std::pair<Register, int64_t>
2468 AMDGPUInstructionSelector::getPtrBaseWithConstantOffset(
2469   Register Root, const MachineRegisterInfo &MRI) const {
2470   MachineInstr *RootI = MRI.getVRegDef(Root);
2471   if (RootI->getOpcode() != TargetOpcode::G_PTR_ADD)
2472     return {Root, 0};
2473 
2474   MachineOperand &RHS = RootI->getOperand(2);
2475   Optional<ValueAndVReg> MaybeOffset
2476     = getConstantVRegValWithLookThrough(RHS.getReg(), MRI, true);
2477   if (!MaybeOffset)
2478     return {Root, 0};
2479   return {RootI->getOperand(1).getReg(), MaybeOffset->Value};
2480 }
2481 
2482 static void addZeroImm(MachineInstrBuilder &MIB) {
2483   MIB.addImm(0);
2484 }
2485 
2486 /// Return a resource descriptor for use with an arbitrary 64-bit pointer. If \p
2487 /// BasePtr is not valid, a null base pointer will be used.
2488 static Register buildRSRC(MachineIRBuilder &B, MachineRegisterInfo &MRI,
2489                           uint32_t FormatLo, uint32_t FormatHi,
2490                           Register BasePtr) {
2491   Register RSrc2 = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
2492   Register RSrc3 = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
2493   Register RSrcHi = MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass);
2494   Register RSrc = MRI.createVirtualRegister(&AMDGPU::SGPR_128RegClass);
2495 
2496   B.buildInstr(AMDGPU::S_MOV_B32)
2497     .addDef(RSrc2)
2498     .addImm(FormatLo);
2499   B.buildInstr(AMDGPU::S_MOV_B32)
2500     .addDef(RSrc3)
2501     .addImm(FormatHi);
2502 
2503   // Build the half of the subregister with the constants before building the
2504   // full 128-bit register. If we are building multiple resource descriptors,
2505   // this will allow CSEing of the 2-component register.
2506   B.buildInstr(AMDGPU::REG_SEQUENCE)
2507     .addDef(RSrcHi)
2508     .addReg(RSrc2)
2509     .addImm(AMDGPU::sub0)
2510     .addReg(RSrc3)
2511     .addImm(AMDGPU::sub1);
2512 
2513   Register RSrcLo = BasePtr;
2514   if (!BasePtr) {
2515     RSrcLo = MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass);
2516     B.buildInstr(AMDGPU::S_MOV_B64)
2517       .addDef(RSrcLo)
2518       .addImm(0);
2519   }
2520 
2521   B.buildInstr(AMDGPU::REG_SEQUENCE)
2522     .addDef(RSrc)
2523     .addReg(RSrcLo)
2524     .addImm(AMDGPU::sub0_sub1)
2525     .addReg(RSrcHi)
2526     .addImm(AMDGPU::sub2_sub3);
2527 
2528   return RSrc;
2529 }
2530 
2531 static Register buildAddr64RSrc(MachineIRBuilder &B, MachineRegisterInfo &MRI,
2532                                 const SIInstrInfo &TII, Register BasePtr) {
2533   uint64_t DefaultFormat = TII.getDefaultRsrcDataFormat();
2534 
2535   // FIXME: Why are half the "default" bits ignored based on the addressing
2536   // mode?
2537   return buildRSRC(B, MRI, 0, Hi_32(DefaultFormat), BasePtr);
2538 }
2539 
2540 static Register buildOffsetSrc(MachineIRBuilder &B, MachineRegisterInfo &MRI,
2541                                const SIInstrInfo &TII, Register BasePtr) {
2542   uint64_t DefaultFormat = TII.getDefaultRsrcDataFormat();
2543 
2544   // FIXME: Why are half the "default" bits ignored based on the addressing
2545   // mode?
2546   return buildRSRC(B, MRI, -1, Hi_32(DefaultFormat), BasePtr);
2547 }
2548 
2549 AMDGPUInstructionSelector::MUBUFAddressData
2550 AMDGPUInstructionSelector::parseMUBUFAddress(Register Src) const {
2551   MUBUFAddressData Data;
2552   Data.N0 = Src;
2553 
2554   Register PtrBase;
2555   int64_t Offset;
2556 
2557   std::tie(PtrBase, Offset) = getPtrBaseWithConstantOffset(Src, *MRI);
2558   if (isUInt<32>(Offset)) {
2559     Data.N0 = PtrBase;
2560     Data.Offset = Offset;
2561   }
2562 
2563   if (MachineInstr *InputAdd
2564       = getOpcodeDef(TargetOpcode::G_PTR_ADD, Data.N0, *MRI)) {
2565     Data.N2 = InputAdd->getOperand(1).getReg();
2566     Data.N3 = InputAdd->getOperand(2).getReg();
2567 
2568     // FIXME: Need to fix extra SGPR->VGPRcopies inserted
2569     // FIXME: Don't know this was defined by operand 0
2570     //
2571     // TODO: Remove this when we have copy folding optimizations after
2572     // RegBankSelect.
2573     Data.N2 = getDefIgnoringCopies(Data.N2, *MRI)->getOperand(0).getReg();
2574     Data.N3 = getDefIgnoringCopies(Data.N3, *MRI)->getOperand(0).getReg();
2575   }
2576 
2577   return Data;
2578 }
2579 
2580 /// Return if the addr64 mubuf mode should be used for the given address.
2581 bool AMDGPUInstructionSelector::shouldUseAddr64(MUBUFAddressData Addr) const {
2582   // (ptr_add N2, N3) -> addr64, or
2583   // (ptr_add (ptr_add N2, N3), C1) -> addr64
2584   if (Addr.N2)
2585     return true;
2586 
2587   const RegisterBank *N0Bank = RBI.getRegBank(Addr.N0, *MRI, TRI);
2588   return N0Bank->getID() == AMDGPU::VGPRRegBankID;
2589 }
2590 
2591 /// Split an immediate offset \p ImmOffset depending on whether it fits in the
2592 /// immediate field. Modifies \p ImmOffset and sets \p SOffset to the variable
2593 /// component.
2594 void AMDGPUInstructionSelector::splitIllegalMUBUFOffset(
2595   MachineIRBuilder &B, Register &SOffset, int64_t &ImmOffset) const {
2596   if (SIInstrInfo::isLegalMUBUFImmOffset(ImmOffset))
2597     return;
2598 
2599   // Illegal offset, store it in soffset.
2600   SOffset = MRI->createVirtualRegister(&AMDGPU::SReg_32RegClass);
2601   B.buildInstr(AMDGPU::S_MOV_B32)
2602     .addDef(SOffset)
2603     .addImm(ImmOffset);
2604   ImmOffset = 0;
2605 }
2606 
2607 bool AMDGPUInstructionSelector::selectMUBUFAddr64Impl(
2608   MachineOperand &Root, Register &VAddr, Register &RSrcReg,
2609   Register &SOffset, int64_t &Offset) const {
2610   // FIXME: Predicates should stop this from reaching here.
2611   // addr64 bit was removed for volcanic islands.
2612   if (!STI.hasAddr64() || STI.useFlatForGlobal())
2613     return false;
2614 
2615   MUBUFAddressData AddrData = parseMUBUFAddress(Root.getReg());
2616   if (!shouldUseAddr64(AddrData))
2617     return false;
2618 
2619   Register N0 = AddrData.N0;
2620   Register N2 = AddrData.N2;
2621   Register N3 = AddrData.N3;
2622   Offset = AddrData.Offset;
2623 
2624   // Base pointer for the SRD.
2625   Register SRDPtr;
2626 
2627   if (N2) {
2628     if (RBI.getRegBank(N2, *MRI, TRI)->getID() == AMDGPU::VGPRRegBankID) {
2629       assert(N3);
2630       if (RBI.getRegBank(N3, *MRI, TRI)->getID() == AMDGPU::VGPRRegBankID) {
2631         // Both N2 and N3 are divergent. Use N0 (the result of the add) as the
2632         // addr64, and construct the default resource from a 0 address.
2633         VAddr = N0;
2634       } else {
2635         SRDPtr = N3;
2636         VAddr = N2;
2637       }
2638     } else {
2639       // N2 is not divergent.
2640       SRDPtr = N2;
2641       VAddr = N3;
2642     }
2643   } else if (RBI.getRegBank(N0, *MRI, TRI)->getID() == AMDGPU::VGPRRegBankID) {
2644     // Use the default null pointer in the resource
2645     VAddr = N0;
2646   } else {
2647     // N0 -> offset, or
2648     // (N0 + C1) -> offset
2649     SRDPtr = N0;
2650   }
2651 
2652   MachineIRBuilder B(*Root.getParent());
2653   RSrcReg = buildAddr64RSrc(B, *MRI, TII, SRDPtr);
2654   splitIllegalMUBUFOffset(B, SOffset, Offset);
2655   return true;
2656 }
2657 
2658 bool AMDGPUInstructionSelector::selectMUBUFOffsetImpl(
2659   MachineOperand &Root, Register &RSrcReg, Register &SOffset,
2660   int64_t &Offset) const {
2661   MUBUFAddressData AddrData = parseMUBUFAddress(Root.getReg());
2662   if (shouldUseAddr64(AddrData))
2663     return false;
2664 
2665   // N0 -> offset, or
2666   // (N0 + C1) -> offset
2667   Register SRDPtr = AddrData.N0;
2668   Offset = AddrData.Offset;
2669 
2670   // TODO: Look through extensions for 32-bit soffset.
2671   MachineIRBuilder B(*Root.getParent());
2672 
2673   RSrcReg = buildOffsetSrc(B, *MRI, TII, SRDPtr);
2674   splitIllegalMUBUFOffset(B, SOffset, Offset);
2675   return true;
2676 }
2677 
2678 InstructionSelector::ComplexRendererFns
2679 AMDGPUInstructionSelector::selectMUBUFAddr64(MachineOperand &Root) const {
2680   Register VAddr;
2681   Register RSrcReg;
2682   Register SOffset;
2683   int64_t Offset = 0;
2684 
2685   if (!selectMUBUFAddr64Impl(Root, VAddr, RSrcReg, SOffset, Offset))
2686     return {};
2687 
2688   // FIXME: Use defaulted operands for trailing 0s and remove from the complex
2689   // pattern.
2690   return {{
2691       [=](MachineInstrBuilder &MIB) {  // rsrc
2692         MIB.addReg(RSrcReg);
2693       },
2694       [=](MachineInstrBuilder &MIB) { // vaddr
2695         MIB.addReg(VAddr);
2696       },
2697       [=](MachineInstrBuilder &MIB) { // soffset
2698         if (SOffset)
2699           MIB.addReg(SOffset);
2700         else
2701           MIB.addImm(0);
2702       },
2703       [=](MachineInstrBuilder &MIB) { // offset
2704         MIB.addImm(Offset);
2705       },
2706       addZeroImm, //  glc
2707       addZeroImm, //  slc
2708       addZeroImm, //  tfe
2709       addZeroImm, //  dlc
2710       addZeroImm  //  swz
2711     }};
2712 }
2713 
2714 InstructionSelector::ComplexRendererFns
2715 AMDGPUInstructionSelector::selectMUBUFOffset(MachineOperand &Root) const {
2716   Register RSrcReg;
2717   Register SOffset;
2718   int64_t Offset = 0;
2719 
2720   if (!selectMUBUFOffsetImpl(Root, RSrcReg, SOffset, Offset))
2721     return {};
2722 
2723   return {{
2724       [=](MachineInstrBuilder &MIB) {  // rsrc
2725         MIB.addReg(RSrcReg);
2726       },
2727       [=](MachineInstrBuilder &MIB) { // soffset
2728         if (SOffset)
2729           MIB.addReg(SOffset);
2730         else
2731           MIB.addImm(0);
2732       },
2733       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); }, // offset
2734       addZeroImm, //  glc
2735       addZeroImm, //  slc
2736       addZeroImm, //  tfe
2737       addZeroImm, //  dlc
2738       addZeroImm  //  swz
2739     }};
2740 }
2741 
2742 InstructionSelector::ComplexRendererFns
2743 AMDGPUInstructionSelector::selectMUBUFAddr64Atomic(MachineOperand &Root) const {
2744   Register VAddr;
2745   Register RSrcReg;
2746   Register SOffset;
2747   int64_t Offset = 0;
2748 
2749   if (!selectMUBUFAddr64Impl(Root, VAddr, RSrcReg, SOffset, Offset))
2750     return {};
2751 
2752   // FIXME: Use defaulted operands for trailing 0s and remove from the complex
2753   // pattern.
2754   return {{
2755       [=](MachineInstrBuilder &MIB) {  // rsrc
2756         MIB.addReg(RSrcReg);
2757       },
2758       [=](MachineInstrBuilder &MIB) { // vaddr
2759         MIB.addReg(VAddr);
2760       },
2761       [=](MachineInstrBuilder &MIB) { // soffset
2762         if (SOffset)
2763           MIB.addReg(SOffset);
2764         else
2765           MIB.addImm(0);
2766       },
2767       [=](MachineInstrBuilder &MIB) { // offset
2768         MIB.addImm(Offset);
2769       },
2770       addZeroImm //  slc
2771     }};
2772 }
2773 
2774 InstructionSelector::ComplexRendererFns
2775 AMDGPUInstructionSelector::selectMUBUFOffsetAtomic(MachineOperand &Root) const {
2776   Register RSrcReg;
2777   Register SOffset;
2778   int64_t Offset = 0;
2779 
2780   if (!selectMUBUFOffsetImpl(Root, RSrcReg, SOffset, Offset))
2781     return {};
2782 
2783   return {{
2784       [=](MachineInstrBuilder &MIB) {  // rsrc
2785         MIB.addReg(RSrcReg);
2786       },
2787       [=](MachineInstrBuilder &MIB) { // soffset
2788         if (SOffset)
2789           MIB.addReg(SOffset);
2790         else
2791           MIB.addImm(0);
2792       },
2793       [=](MachineInstrBuilder &MIB) { MIB.addImm(Offset); }, // offset
2794       addZeroImm //  slc
2795     }};
2796 }
2797 
2798 void AMDGPUInstructionSelector::renderTruncImm32(MachineInstrBuilder &MIB,
2799                                                  const MachineInstr &MI,
2800                                                  int OpIdx) const {
2801   assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
2802          "Expected G_CONSTANT");
2803   MIB.addImm(MI.getOperand(1).getCImm()->getSExtValue());
2804 }
2805 
2806 void AMDGPUInstructionSelector::renderNegateImm(MachineInstrBuilder &MIB,
2807                                                 const MachineInstr &MI,
2808                                                 int OpIdx) const {
2809   assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
2810          "Expected G_CONSTANT");
2811   MIB.addImm(-MI.getOperand(1).getCImm()->getSExtValue());
2812 }
2813 
2814 void AMDGPUInstructionSelector::renderBitcastImm(MachineInstrBuilder &MIB,
2815                                                  const MachineInstr &MI,
2816                                                  int OpIdx) const {
2817   assert(OpIdx == -1);
2818 
2819   const MachineOperand &Op = MI.getOperand(1);
2820   if (MI.getOpcode() == TargetOpcode::G_FCONSTANT)
2821     MIB.addImm(Op.getFPImm()->getValueAPF().bitcastToAPInt().getZExtValue());
2822   else {
2823     assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && "Expected G_CONSTANT");
2824     MIB.addImm(Op.getCImm()->getSExtValue());
2825   }
2826 }
2827 
2828 void AMDGPUInstructionSelector::renderPopcntImm(MachineInstrBuilder &MIB,
2829                                                 const MachineInstr &MI,
2830                                                 int OpIdx) const {
2831   assert(MI.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
2832          "Expected G_CONSTANT");
2833   MIB.addImm(MI.getOperand(1).getCImm()->getValue().countPopulation());
2834 }
2835 
2836 /// This only really exists to satisfy DAG type checking machinery, so is a
2837 /// no-op here.
2838 void AMDGPUInstructionSelector::renderTruncTImm(MachineInstrBuilder &MIB,
2839                                                 const MachineInstr &MI,
2840                                                 int OpIdx) const {
2841   MIB.addImm(MI.getOperand(OpIdx).getImm());
2842 }
2843 
2844 void AMDGPUInstructionSelector::renderExtractGLC(MachineInstrBuilder &MIB,
2845                                                  const MachineInstr &MI,
2846                                                  int OpIdx) const {
2847   assert(OpIdx >= 0 && "expected to match an immediate operand");
2848   MIB.addImm(MI.getOperand(OpIdx).getImm() & 1);
2849 }
2850 
2851 void AMDGPUInstructionSelector::renderExtractSLC(MachineInstrBuilder &MIB,
2852                                                  const MachineInstr &MI,
2853                                                  int OpIdx) const {
2854   assert(OpIdx >= 0 && "expected to match an immediate operand");
2855   MIB.addImm((MI.getOperand(OpIdx).getImm() >> 1) & 1);
2856 }
2857 
2858 void AMDGPUInstructionSelector::renderExtractDLC(MachineInstrBuilder &MIB,
2859                                                  const MachineInstr &MI,
2860                                                  int OpIdx) const {
2861   assert(OpIdx >= 0 && "expected to match an immediate operand");
2862   MIB.addImm((MI.getOperand(OpIdx).getImm() >> 2) & 1);
2863 }
2864 
2865 void AMDGPUInstructionSelector::renderExtractSWZ(MachineInstrBuilder &MIB,
2866                                                  const MachineInstr &MI,
2867                                                  int OpIdx) const {
2868   assert(OpIdx >= 0 && "expected to match an immediate operand");
2869   MIB.addImm((MI.getOperand(OpIdx).getImm() >> 3) & 1);
2870 }
2871 
2872 bool AMDGPUInstructionSelector::isInlineImmediate16(int64_t Imm) const {
2873   return AMDGPU::isInlinableLiteral16(Imm, STI.hasInv2PiInlineImm());
2874 }
2875 
2876 bool AMDGPUInstructionSelector::isInlineImmediate32(int64_t Imm) const {
2877   return AMDGPU::isInlinableLiteral32(Imm, STI.hasInv2PiInlineImm());
2878 }
2879 
2880 bool AMDGPUInstructionSelector::isInlineImmediate64(int64_t Imm) const {
2881   return AMDGPU::isInlinableLiteral64(Imm, STI.hasInv2PiInlineImm());
2882 }
2883 
2884 bool AMDGPUInstructionSelector::isInlineImmediate(const APFloat &Imm) const {
2885   return TII.isInlineConstant(Imm);
2886 }
2887