xref: /llvm-project/llvm/lib/Target/SPIRV/SPIRVInstructionSelector.cpp (revision aab25f20f6c06bab7aac6fb83d54705ec4cdfadd)
1 //===- SPIRVInstructionSelector.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 //
9 // This file implements the targeting of the InstructionSelector class for
10 // SPIRV.
11 // TODO: This should be generated by TableGen.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "MCTargetDesc/SPIRVBaseInfo.h"
16 #include "MCTargetDesc/SPIRVMCTargetDesc.h"
17 #include "SPIRV.h"
18 #include "SPIRVGlobalRegistry.h"
19 #include "SPIRVInstrInfo.h"
20 #include "SPIRVRegisterBankInfo.h"
21 #include "SPIRVRegisterInfo.h"
22 #include "SPIRVTargetMachine.h"
23 #include "SPIRVUtils.h"
24 #include "llvm/ADT/APFloat.h"
25 #include "llvm/ADT/StringExtras.h"
26 #include "llvm/CodeGen/GlobalISel/GIMatchTableExecutorImpl.h"
27 #include "llvm/CodeGen/GlobalISel/GenericMachineInstrs.h"
28 #include "llvm/CodeGen/GlobalISel/InstructionSelector.h"
29 #include "llvm/CodeGen/MachineInstrBuilder.h"
30 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
31 #include "llvm/CodeGen/MachineRegisterInfo.h"
32 #include "llvm/CodeGen/Register.h"
33 #include "llvm/CodeGen/TargetOpcodes.h"
34 #include "llvm/IR/IntrinsicsSPIRV.h"
35 #include "llvm/Support/Debug.h"
36 #include "llvm/Support/ErrorHandling.h"
37 
38 #define DEBUG_TYPE "spirv-isel"
39 
40 using namespace llvm;
41 namespace CL = SPIRV::OpenCLExtInst;
42 namespace GL = SPIRV::GLSLExtInst;
43 
44 using ExtInstList =
45     std::vector<std::pair<SPIRV::InstructionSet::InstructionSet, uint32_t>>;
46 
47 namespace {
48 
49 llvm::SPIRV::SelectionControl::SelectionControl
50 getSelectionOperandForImm(int Imm) {
51   if (Imm == 2)
52     return SPIRV::SelectionControl::Flatten;
53   if (Imm == 1)
54     return SPIRV::SelectionControl::DontFlatten;
55   if (Imm == 0)
56     return SPIRV::SelectionControl::None;
57   llvm_unreachable("Invalid immediate");
58 }
59 
60 #define GET_GLOBALISEL_PREDICATE_BITSET
61 #include "SPIRVGenGlobalISel.inc"
62 #undef GET_GLOBALISEL_PREDICATE_BITSET
63 
64 class SPIRVInstructionSelector : public InstructionSelector {
65   const SPIRVSubtarget &STI;
66   const SPIRVInstrInfo &TII;
67   const SPIRVRegisterInfo &TRI;
68   const RegisterBankInfo &RBI;
69   SPIRVGlobalRegistry &GR;
70   MachineRegisterInfo *MRI;
71   MachineFunction *HasVRegsReset = nullptr;
72 
73   /// We need to keep track of the number we give to anonymous global values to
74   /// generate the same name every time when this is needed.
75   mutable DenseMap<const GlobalValue *, unsigned> UnnamedGlobalIDs;
76   SmallPtrSet<MachineInstr *, 8> DeadMIs;
77 
78 public:
79   SPIRVInstructionSelector(const SPIRVTargetMachine &TM,
80                            const SPIRVSubtarget &ST,
81                            const RegisterBankInfo &RBI);
82   void setupMF(MachineFunction &MF, GISelKnownBits *KB,
83                CodeGenCoverage *CoverageInfo, ProfileSummaryInfo *PSI,
84                BlockFrequencyInfo *BFI) override;
85   // Common selection code. Instruction-specific selection occurs in spvSelect.
86   bool select(MachineInstr &I) override;
87   static const char *getName() { return DEBUG_TYPE; }
88 
89 #define GET_GLOBALISEL_PREDICATES_DECL
90 #include "SPIRVGenGlobalISel.inc"
91 #undef GET_GLOBALISEL_PREDICATES_DECL
92 
93 #define GET_GLOBALISEL_TEMPORARIES_DECL
94 #include "SPIRVGenGlobalISel.inc"
95 #undef GET_GLOBALISEL_TEMPORARIES_DECL
96 
97 private:
98   void resetVRegsType(MachineFunction &MF);
99 
100   // tblgen-erated 'select' implementation, used as the initial selector for
101   // the patterns that don't require complex C++.
102   bool selectImpl(MachineInstr &I, CodeGenCoverage &CoverageInfo) const;
103 
104   // All instruction-specific selection that didn't happen in "select()".
105   // Is basically a large Switch/Case delegating to all other select method.
106   bool spvSelect(Register ResVReg, const SPIRVType *ResType,
107                  MachineInstr &I) const;
108 
109   bool selectFirstBitHigh(Register ResVReg, const SPIRVType *ResType,
110                           MachineInstr &I, bool IsSigned) const;
111 
112   bool selectFirstBitLow(Register ResVReg, const SPIRVType *ResType,
113                          MachineInstr &I) const;
114 
115   bool selectFirstBitSet16(Register ResVReg, const SPIRVType *ResType,
116                            MachineInstr &I, unsigned ExtendOpcode,
117                            unsigned BitSetOpcode) const;
118 
119   bool selectFirstBitSet32(Register ResVReg, const SPIRVType *ResType,
120                            MachineInstr &I, Register SrcReg,
121                            unsigned BitSetOpcode) const;
122 
123   bool selectFirstBitSet64(Register ResVReg, const SPIRVType *ResType,
124                            MachineInstr &I, Register SrcReg,
125                            unsigned BitSetOpcode, bool SwapPrimarySide) const;
126 
127   bool selectFirstBitSet64Overflow(Register ResVReg, const SPIRVType *ResType,
128                                    MachineInstr &I, Register SrcReg,
129                                    unsigned BitSetOpcode,
130                                    bool SwapPrimarySide) const;
131 
132   bool selectGlobalValue(Register ResVReg, MachineInstr &I,
133                          const MachineInstr *Init = nullptr) const;
134 
135   bool selectOpWithSrcs(Register ResVReg, const SPIRVType *ResType,
136                         MachineInstr &I, std::vector<Register> SrcRegs,
137                         unsigned Opcode) const;
138 
139   bool selectUnOp(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
140                   unsigned Opcode) const;
141 
142   bool selectBitcast(Register ResVReg, const SPIRVType *ResType,
143                      MachineInstr &I) const;
144 
145   bool selectLoad(Register ResVReg, const SPIRVType *ResType,
146                   MachineInstr &I) const;
147   bool selectStore(MachineInstr &I) const;
148 
149   bool selectStackSave(Register ResVReg, const SPIRVType *ResType,
150                        MachineInstr &I) const;
151   bool selectStackRestore(MachineInstr &I) const;
152 
153   bool selectMemOperation(Register ResVReg, MachineInstr &I) const;
154 
155   bool selectAtomicRMW(Register ResVReg, const SPIRVType *ResType,
156                        MachineInstr &I, unsigned NewOpcode,
157                        unsigned NegateOpcode = 0) const;
158 
159   bool selectAtomicCmpXchg(Register ResVReg, const SPIRVType *ResType,
160                            MachineInstr &I) const;
161 
162   bool selectFence(MachineInstr &I) const;
163 
164   bool selectAddrSpaceCast(Register ResVReg, const SPIRVType *ResType,
165                            MachineInstr &I) const;
166 
167   bool selectAnyOrAll(Register ResVReg, const SPIRVType *ResType,
168                       MachineInstr &I, unsigned OpType) const;
169 
170   bool selectAll(Register ResVReg, const SPIRVType *ResType,
171                  MachineInstr &I) const;
172 
173   bool selectAny(Register ResVReg, const SPIRVType *ResType,
174                  MachineInstr &I) const;
175 
176   bool selectBitreverse(Register ResVReg, const SPIRVType *ResType,
177                         MachineInstr &I) const;
178 
179   bool selectBuildVector(Register ResVReg, const SPIRVType *ResType,
180                          MachineInstr &I) const;
181   bool selectSplatVector(Register ResVReg, const SPIRVType *ResType,
182                          MachineInstr &I) const;
183 
184   bool selectCmp(Register ResVReg, const SPIRVType *ResType,
185                  unsigned comparisonOpcode, MachineInstr &I) const;
186   bool selectCross(Register ResVReg, const SPIRVType *ResType,
187                    MachineInstr &I) const;
188   bool selectDiscard(Register ResVReg, const SPIRVType *ResType,
189                      MachineInstr &I) const;
190 
191   bool selectICmp(Register ResVReg, const SPIRVType *ResType,
192                   MachineInstr &I) const;
193   bool selectFCmp(Register ResVReg, const SPIRVType *ResType,
194                   MachineInstr &I) const;
195 
196   bool selectSign(Register ResVReg, const SPIRVType *ResType,
197                   MachineInstr &I) const;
198 
199   bool selectFloatDot(Register ResVReg, const SPIRVType *ResType,
200                       MachineInstr &I) const;
201 
202   bool selectOverflowArith(Register ResVReg, const SPIRVType *ResType,
203                            MachineInstr &I, unsigned Opcode) const;
204 
205   bool selectIntegerDot(Register ResVReg, const SPIRVType *ResType,
206                         MachineInstr &I, bool Signed) const;
207 
208   bool selectIntegerDotExpansion(Register ResVReg, const SPIRVType *ResType,
209                                  MachineInstr &I) const;
210 
211   template <bool Signed>
212   bool selectDot4AddPacked(Register ResVReg, const SPIRVType *ResType,
213                            MachineInstr &I) const;
214   template <bool Signed>
215   bool selectDot4AddPackedExpansion(Register ResVReg, const SPIRVType *ResType,
216                                     MachineInstr &I) const;
217 
218   bool selectWaveReduceMax(Register ResVReg, const SPIRVType *ResType,
219                            MachineInstr &I, bool IsUnsigned) const;
220 
221   bool selectWaveReduceSum(Register ResVReg, const SPIRVType *ResType,
222                            MachineInstr &I) const;
223 
224   void renderImm32(MachineInstrBuilder &MIB, const MachineInstr &I,
225                    int OpIdx) const;
226   void renderFImm64(MachineInstrBuilder &MIB, const MachineInstr &I,
227                     int OpIdx) const;
228 
229   bool selectConst(Register ResVReg, const SPIRVType *ResType, const APInt &Imm,
230                    MachineInstr &I) const;
231 
232   bool selectSelect(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
233                     bool IsSigned) const;
234   bool selectIToF(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
235                   bool IsSigned, unsigned Opcode) const;
236   bool selectExt(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
237                  bool IsSigned) const;
238 
239   bool selectTrunc(Register ResVReg, const SPIRVType *ResType,
240                    MachineInstr &I) const;
241 
242   bool selectSUCmp(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
243                    bool IsSigned) const;
244 
245   bool selectIntToBool(Register IntReg, Register ResVReg, MachineInstr &I,
246                        const SPIRVType *intTy, const SPIRVType *boolTy) const;
247 
248   bool selectOpUndef(Register ResVReg, const SPIRVType *ResType,
249                      MachineInstr &I) const;
250   bool selectFreeze(Register ResVReg, const SPIRVType *ResType,
251                     MachineInstr &I) const;
252   bool selectIntrinsic(Register ResVReg, const SPIRVType *ResType,
253                        MachineInstr &I) const;
254   bool selectExtractVal(Register ResVReg, const SPIRVType *ResType,
255                         MachineInstr &I) const;
256   bool selectInsertVal(Register ResVReg, const SPIRVType *ResType,
257                        MachineInstr &I) const;
258   bool selectExtractElt(Register ResVReg, const SPIRVType *ResType,
259                         MachineInstr &I) const;
260   bool selectInsertElt(Register ResVReg, const SPIRVType *ResType,
261                        MachineInstr &I) const;
262   bool selectGEP(Register ResVReg, const SPIRVType *ResType,
263                  MachineInstr &I) const;
264 
265   bool selectFrameIndex(Register ResVReg, const SPIRVType *ResType,
266                         MachineInstr &I) const;
267   bool selectAllocaArray(Register ResVReg, const SPIRVType *ResType,
268                          MachineInstr &I) const;
269 
270   bool selectBranch(MachineInstr &I) const;
271   bool selectBranchCond(MachineInstr &I) const;
272 
273   bool selectPhi(Register ResVReg, const SPIRVType *ResType,
274                  MachineInstr &I) const;
275 
276   [[maybe_unused]] bool selectExtInst(Register ResVReg,
277                                       const SPIRVType *RestType,
278                                       MachineInstr &I,
279                                       GL::GLSLExtInst GLInst) const;
280   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
281                      MachineInstr &I, CL::OpenCLExtInst CLInst) const;
282   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
283                      MachineInstr &I, CL::OpenCLExtInst CLInst,
284                      GL::GLSLExtInst GLInst) const;
285   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
286                      MachineInstr &I, const ExtInstList &ExtInsts) const;
287 
288   bool selectLog10(Register ResVReg, const SPIRVType *ResType,
289                    MachineInstr &I) const;
290 
291   bool selectSaturate(Register ResVReg, const SPIRVType *ResType,
292                       MachineInstr &I) const;
293 
294   bool selectWaveOpInst(Register ResVReg, const SPIRVType *ResType,
295                         MachineInstr &I, unsigned Opcode) const;
296 
297   bool selectWaveActiveCountBits(Register ResVReg, const SPIRVType *ResType,
298                                  MachineInstr &I) const;
299 
300   bool selectUnmergeValues(MachineInstr &I) const;
301 
302   bool selectHandleFromBinding(Register &ResVReg, const SPIRVType *ResType,
303                                MachineInstr &I) const;
304 
305   bool selectReadImageIntrinsic(Register &ResVReg, const SPIRVType *ResType,
306                                 MachineInstr &I) const;
307   bool selectImageWriteIntrinsic(MachineInstr &I) const;
308   bool selectResourceGetPointer(Register &ResVReg, const SPIRVType *ResType,
309                                 MachineInstr &I) const;
310 
311   // Utilities
312   std::pair<Register, bool>
313   buildI32Constant(uint32_t Val, MachineInstr &I,
314                    const SPIRVType *ResType = nullptr) const;
315 
316   Register buildZerosVal(const SPIRVType *ResType, MachineInstr &I) const;
317   Register buildZerosValF(const SPIRVType *ResType, MachineInstr &I) const;
318   Register buildOnesVal(bool AllOnes, const SPIRVType *ResType,
319                         MachineInstr &I) const;
320   Register buildOnesValF(const SPIRVType *ResType, MachineInstr &I) const;
321 
322   bool wrapIntoSpecConstantOp(MachineInstr &I,
323                               SmallVector<Register> &CompositeArgs) const;
324 
325   Register getUcharPtrTypeReg(MachineInstr &I,
326                               SPIRV::StorageClass::StorageClass SC) const;
327   MachineInstrBuilder buildSpecConstantOp(MachineInstr &I, Register Dest,
328                                           Register Src, Register DestType,
329                                           uint32_t Opcode) const;
330   MachineInstrBuilder buildConstGenericPtr(MachineInstr &I, Register SrcPtr,
331                                            SPIRVType *SrcPtrTy) const;
332   Register buildPointerToResource(const SPIRVType *ResType, uint32_t Set,
333                                   uint32_t Binding, uint32_t ArraySize,
334                                   Register IndexReg, bool IsNonUniform,
335                                   MachineIRBuilder MIRBuilder) const;
336   SPIRVType *widenTypeToVec4(const SPIRVType *Type, MachineInstr &I) const;
337   bool extractSubvector(Register &ResVReg, const SPIRVType *ResType,
338                         Register &ReadReg, MachineInstr &InsertionPoint) const;
339   bool generateImageRead(Register &ResVReg, const SPIRVType *ResType,
340                          Register ImageReg, Register IdxReg, DebugLoc Loc,
341                          MachineInstr &Pos) const;
342   bool BuildCOPY(Register DestReg, Register SrcReg, MachineInstr &I) const;
343   bool loadVec3BuiltinInputID(SPIRV::BuiltIn::BuiltIn BuiltInValue,
344                               Register ResVReg, const SPIRVType *ResType,
345                               MachineInstr &I) const;
346   bool loadHandleBeforePosition(Register &HandleReg, const SPIRVType *ResType,
347                                 GIntrinsic &HandleDef, MachineInstr &Pos) const;
348 };
349 
350 } // end anonymous namespace
351 
352 #define GET_GLOBALISEL_IMPL
353 #include "SPIRVGenGlobalISel.inc"
354 #undef GET_GLOBALISEL_IMPL
355 
356 SPIRVInstructionSelector::SPIRVInstructionSelector(const SPIRVTargetMachine &TM,
357                                                    const SPIRVSubtarget &ST,
358                                                    const RegisterBankInfo &RBI)
359     : InstructionSelector(), STI(ST), TII(*ST.getInstrInfo()),
360       TRI(*ST.getRegisterInfo()), RBI(RBI), GR(*ST.getSPIRVGlobalRegistry()),
361 #define GET_GLOBALISEL_PREDICATES_INIT
362 #include "SPIRVGenGlobalISel.inc"
363 #undef GET_GLOBALISEL_PREDICATES_INIT
364 #define GET_GLOBALISEL_TEMPORARIES_INIT
365 #include "SPIRVGenGlobalISel.inc"
366 #undef GET_GLOBALISEL_TEMPORARIES_INIT
367 {
368 }
369 
370 void SPIRVInstructionSelector::setupMF(MachineFunction &MF, GISelKnownBits *KB,
371                                        CodeGenCoverage *CoverageInfo,
372                                        ProfileSummaryInfo *PSI,
373                                        BlockFrequencyInfo *BFI) {
374   MRI = &MF.getRegInfo();
375   GR.setCurrentFunc(MF);
376   InstructionSelector::setupMF(MF, KB, CoverageInfo, PSI, BFI);
377 }
378 
379 // Ensure that register classes correspond to pattern matching rules.
380 void SPIRVInstructionSelector::resetVRegsType(MachineFunction &MF) {
381   if (HasVRegsReset == &MF)
382     return;
383   HasVRegsReset = &MF;
384 
385   MachineRegisterInfo &MRI = MF.getRegInfo();
386   for (unsigned I = 0, E = MRI.getNumVirtRegs(); I != E; ++I) {
387     Register Reg = Register::index2VirtReg(I);
388     LLT RegType = MRI.getType(Reg);
389     if (RegType.isScalar())
390       MRI.setType(Reg, LLT::scalar(64));
391     else if (RegType.isPointer())
392       MRI.setType(Reg, LLT::pointer(0, 64));
393     else if (RegType.isVector())
394       MRI.setType(Reg, LLT::fixed_vector(2, LLT::scalar(64)));
395   }
396   for (const auto &MBB : MF) {
397     for (const auto &MI : MBB) {
398       if (MI.getOpcode() != SPIRV::ASSIGN_TYPE)
399         continue;
400       Register DstReg = MI.getOperand(0).getReg();
401       LLT DstType = MRI.getType(DstReg);
402       Register SrcReg = MI.getOperand(1).getReg();
403       LLT SrcType = MRI.getType(SrcReg);
404       if (DstType != SrcType)
405         MRI.setType(DstReg, MRI.getType(SrcReg));
406 
407       const TargetRegisterClass *DstRC = MRI.getRegClassOrNull(DstReg);
408       const TargetRegisterClass *SrcRC = MRI.getRegClassOrNull(SrcReg);
409       if (DstRC != SrcRC && SrcRC)
410         MRI.setRegClass(DstReg, SrcRC);
411     }
412   }
413 }
414 
415 static bool isImm(const MachineOperand &MO, MachineRegisterInfo *MRI);
416 
417 // Defined in SPIRVLegalizerInfo.cpp.
418 extern bool isTypeFoldingSupported(unsigned Opcode);
419 
420 bool isDead(const MachineInstr &MI, const MachineRegisterInfo &MRI) {
421   for (const auto &MO : MI.all_defs()) {
422     Register Reg = MO.getReg();
423     if (Reg.isPhysical() || !MRI.use_nodbg_empty(Reg))
424       return false;
425   }
426   if (MI.getOpcode() == TargetOpcode::LOCAL_ESCAPE || MI.isFakeUse() ||
427       MI.isLifetimeMarker())
428     return false;
429   if (MI.isPHI())
430     return true;
431   if (MI.mayStore() || MI.isCall() ||
432       (MI.mayLoad() && MI.hasOrderedMemoryRef()) || MI.isPosition() ||
433       MI.isDebugInstr() || MI.isTerminator() || MI.isJumpTableDebugInfo())
434     return false;
435   return true;
436 }
437 
438 bool SPIRVInstructionSelector::select(MachineInstr &I) {
439   resetVRegsType(*I.getParent()->getParent());
440 
441   assert(I.getParent() && "Instruction should be in a basic block!");
442   assert(I.getParent()->getParent() && "Instruction should be in a function!");
443 
444   Register Opcode = I.getOpcode();
445   // If it's not a GMIR instruction, we've selected it already.
446   if (!isPreISelGenericOpcode(Opcode)) {
447     if (Opcode == SPIRV::ASSIGN_TYPE) { // These pseudos aren't needed any more.
448       Register DstReg = I.getOperand(0).getReg();
449       Register SrcReg = I.getOperand(1).getReg();
450       auto *Def = MRI->getVRegDef(SrcReg);
451       if (isTypeFoldingSupported(Def->getOpcode())) {
452         bool Res = selectImpl(I, *CoverageInfo);
453         LLVM_DEBUG({
454           if (!Res && Def->getOpcode() != TargetOpcode::G_CONSTANT) {
455             dbgs() << "Unexpected pattern in ASSIGN_TYPE.\nInstruction: ";
456             I.print(dbgs());
457           }
458         });
459         assert(Res || Def->getOpcode() == TargetOpcode::G_CONSTANT);
460         if (Res) {
461           if (!isTriviallyDead(*Def, *MRI) && isDead(*Def, *MRI))
462             DeadMIs.insert(Def);
463           return Res;
464         }
465       }
466       MRI->setRegClass(SrcReg, MRI->getRegClass(DstReg));
467       MRI->replaceRegWith(SrcReg, DstReg);
468       GR.invalidateMachineInstr(&I);
469       I.removeFromParent();
470       return true;
471     } else if (I.getNumDefs() == 1) {
472       // Make all vregs 64 bits (for SPIR-V IDs).
473       MRI->setType(I.getOperand(0).getReg(), LLT::scalar(64));
474     }
475     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
476   }
477 
478   if (DeadMIs.contains(&I)) {
479     // if the instruction has been already made dead by folding it away
480     // erase it
481     LLVM_DEBUG(dbgs() << "Instruction is folded and dead.\n");
482     salvageDebugInfo(*MRI, I);
483     GR.invalidateMachineInstr(&I);
484     I.eraseFromParent();
485     return true;
486   }
487 
488   if (I.getNumOperands() != I.getNumExplicitOperands()) {
489     LLVM_DEBUG(errs() << "Generic instr has unexpected implicit operands\n");
490     return false;
491   }
492 
493   // Common code for getting return reg+type, and removing selected instr
494   // from parent occurs here. Instr-specific selection happens in spvSelect().
495   bool HasDefs = I.getNumDefs() > 0;
496   Register ResVReg = HasDefs ? I.getOperand(0).getReg() : Register(0);
497   SPIRVType *ResType = HasDefs ? GR.getSPIRVTypeForVReg(ResVReg) : nullptr;
498   assert(!HasDefs || ResType || I.getOpcode() == TargetOpcode::G_GLOBAL_VALUE);
499   if (spvSelect(ResVReg, ResType, I)) {
500     if (HasDefs) // Make all vregs 64 bits (for SPIR-V IDs).
501       for (unsigned i = 0; i < I.getNumDefs(); ++i)
502         MRI->setType(I.getOperand(i).getReg(), LLT::scalar(64));
503     GR.invalidateMachineInstr(&I);
504     I.removeFromParent();
505     return true;
506   }
507   return false;
508 }
509 
510 static bool mayApplyGenericSelection(unsigned Opcode) {
511   switch (Opcode) {
512   case TargetOpcode::G_CONSTANT:
513     return false;
514   case TargetOpcode::G_SADDO:
515   case TargetOpcode::G_SSUBO:
516     return true;
517   }
518   return isTypeFoldingSupported(Opcode);
519 }
520 
521 bool SPIRVInstructionSelector::BuildCOPY(Register DestReg, Register SrcReg,
522                                          MachineInstr &I) const {
523   const TargetRegisterClass *DstRC = MRI->getRegClassOrNull(DestReg);
524   const TargetRegisterClass *SrcRC = MRI->getRegClassOrNull(SrcReg);
525   if (DstRC != SrcRC && SrcRC)
526     MRI->setRegClass(DestReg, SrcRC);
527   return BuildMI(*I.getParent(), I, I.getDebugLoc(),
528                  TII.get(TargetOpcode::COPY))
529       .addDef(DestReg)
530       .addUse(SrcReg)
531       .constrainAllUses(TII, TRI, RBI);
532 }
533 
534 bool SPIRVInstructionSelector::spvSelect(Register ResVReg,
535                                          const SPIRVType *ResType,
536                                          MachineInstr &I) const {
537   const unsigned Opcode = I.getOpcode();
538   if (mayApplyGenericSelection(Opcode))
539     return selectImpl(I, *CoverageInfo);
540   switch (Opcode) {
541   case TargetOpcode::G_CONSTANT:
542     return selectConst(ResVReg, ResType, I.getOperand(1).getCImm()->getValue(),
543                        I);
544   case TargetOpcode::G_GLOBAL_VALUE:
545     return selectGlobalValue(ResVReg, I);
546   case TargetOpcode::G_IMPLICIT_DEF:
547     return selectOpUndef(ResVReg, ResType, I);
548   case TargetOpcode::G_FREEZE:
549     return selectFreeze(ResVReg, ResType, I);
550 
551   case TargetOpcode::G_INTRINSIC:
552   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
553   case TargetOpcode::G_INTRINSIC_CONVERGENT:
554   case TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS:
555     return selectIntrinsic(ResVReg, ResType, I);
556   case TargetOpcode::G_BITREVERSE:
557     return selectBitreverse(ResVReg, ResType, I);
558 
559   case TargetOpcode::G_BUILD_VECTOR:
560     return selectBuildVector(ResVReg, ResType, I);
561   case TargetOpcode::G_SPLAT_VECTOR:
562     return selectSplatVector(ResVReg, ResType, I);
563 
564   case TargetOpcode::G_SHUFFLE_VECTOR: {
565     MachineBasicBlock &BB = *I.getParent();
566     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorShuffle))
567                    .addDef(ResVReg)
568                    .addUse(GR.getSPIRVTypeID(ResType))
569                    .addUse(I.getOperand(1).getReg())
570                    .addUse(I.getOperand(2).getReg());
571     for (auto V : I.getOperand(3).getShuffleMask())
572       MIB.addImm(V);
573     return MIB.constrainAllUses(TII, TRI, RBI);
574   }
575   case TargetOpcode::G_MEMMOVE:
576   case TargetOpcode::G_MEMCPY:
577   case TargetOpcode::G_MEMSET:
578     return selectMemOperation(ResVReg, I);
579 
580   case TargetOpcode::G_ICMP:
581     return selectICmp(ResVReg, ResType, I);
582   case TargetOpcode::G_FCMP:
583     return selectFCmp(ResVReg, ResType, I);
584 
585   case TargetOpcode::G_FRAME_INDEX:
586     return selectFrameIndex(ResVReg, ResType, I);
587 
588   case TargetOpcode::G_LOAD:
589     return selectLoad(ResVReg, ResType, I);
590   case TargetOpcode::G_STORE:
591     return selectStore(I);
592 
593   case TargetOpcode::G_BR:
594     return selectBranch(I);
595   case TargetOpcode::G_BRCOND:
596     return selectBranchCond(I);
597 
598   case TargetOpcode::G_PHI:
599     return selectPhi(ResVReg, ResType, I);
600 
601   case TargetOpcode::G_FPTOSI:
602     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertFToS);
603   case TargetOpcode::G_FPTOUI:
604     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertFToU);
605 
606   case TargetOpcode::G_SITOFP:
607     return selectIToF(ResVReg, ResType, I, true, SPIRV::OpConvertSToF);
608   case TargetOpcode::G_UITOFP:
609     return selectIToF(ResVReg, ResType, I, false, SPIRV::OpConvertUToF);
610 
611   case TargetOpcode::G_CTPOP:
612     return selectUnOp(ResVReg, ResType, I, SPIRV::OpBitCount);
613   case TargetOpcode::G_SMIN:
614     return selectExtInst(ResVReg, ResType, I, CL::s_min, GL::SMin);
615   case TargetOpcode::G_UMIN:
616     return selectExtInst(ResVReg, ResType, I, CL::u_min, GL::UMin);
617 
618   case TargetOpcode::G_SMAX:
619     return selectExtInst(ResVReg, ResType, I, CL::s_max, GL::SMax);
620   case TargetOpcode::G_UMAX:
621     return selectExtInst(ResVReg, ResType, I, CL::u_max, GL::UMax);
622 
623   case TargetOpcode::G_SCMP:
624     return selectSUCmp(ResVReg, ResType, I, true);
625   case TargetOpcode::G_UCMP:
626     return selectSUCmp(ResVReg, ResType, I, false);
627 
628   case TargetOpcode::G_STRICT_FMA:
629   case TargetOpcode::G_FMA:
630     return selectExtInst(ResVReg, ResType, I, CL::fma, GL::Fma);
631 
632   case TargetOpcode::G_STRICT_FLDEXP:
633     return selectExtInst(ResVReg, ResType, I, CL::ldexp);
634 
635   case TargetOpcode::G_FPOW:
636     return selectExtInst(ResVReg, ResType, I, CL::pow, GL::Pow);
637   case TargetOpcode::G_FPOWI:
638     return selectExtInst(ResVReg, ResType, I, CL::pown);
639 
640   case TargetOpcode::G_FEXP:
641     return selectExtInst(ResVReg, ResType, I, CL::exp, GL::Exp);
642   case TargetOpcode::G_FEXP2:
643     return selectExtInst(ResVReg, ResType, I, CL::exp2, GL::Exp2);
644 
645   case TargetOpcode::G_FLOG:
646     return selectExtInst(ResVReg, ResType, I, CL::log, GL::Log);
647   case TargetOpcode::G_FLOG2:
648     return selectExtInst(ResVReg, ResType, I, CL::log2, GL::Log2);
649   case TargetOpcode::G_FLOG10:
650     return selectLog10(ResVReg, ResType, I);
651 
652   case TargetOpcode::G_FABS:
653     return selectExtInst(ResVReg, ResType, I, CL::fabs, GL::FAbs);
654   case TargetOpcode::G_ABS:
655     return selectExtInst(ResVReg, ResType, I, CL::s_abs, GL::SAbs);
656 
657   case TargetOpcode::G_FMINNUM:
658   case TargetOpcode::G_FMINIMUM:
659     return selectExtInst(ResVReg, ResType, I, CL::fmin, GL::NMin);
660   case TargetOpcode::G_FMAXNUM:
661   case TargetOpcode::G_FMAXIMUM:
662     return selectExtInst(ResVReg, ResType, I, CL::fmax, GL::NMax);
663 
664   case TargetOpcode::G_FCOPYSIGN:
665     return selectExtInst(ResVReg, ResType, I, CL::copysign);
666 
667   case TargetOpcode::G_FCEIL:
668     return selectExtInst(ResVReg, ResType, I, CL::ceil, GL::Ceil);
669   case TargetOpcode::G_FFLOOR:
670     return selectExtInst(ResVReg, ResType, I, CL::floor, GL::Floor);
671 
672   case TargetOpcode::G_FCOS:
673     return selectExtInst(ResVReg, ResType, I, CL::cos, GL::Cos);
674   case TargetOpcode::G_FSIN:
675     return selectExtInst(ResVReg, ResType, I, CL::sin, GL::Sin);
676   case TargetOpcode::G_FTAN:
677     return selectExtInst(ResVReg, ResType, I, CL::tan, GL::Tan);
678   case TargetOpcode::G_FACOS:
679     return selectExtInst(ResVReg, ResType, I, CL::acos, GL::Acos);
680   case TargetOpcode::G_FASIN:
681     return selectExtInst(ResVReg, ResType, I, CL::asin, GL::Asin);
682   case TargetOpcode::G_FATAN:
683     return selectExtInst(ResVReg, ResType, I, CL::atan, GL::Atan);
684   case TargetOpcode::G_FATAN2:
685     return selectExtInst(ResVReg, ResType, I, CL::atan2, GL::Atan2);
686   case TargetOpcode::G_FCOSH:
687     return selectExtInst(ResVReg, ResType, I, CL::cosh, GL::Cosh);
688   case TargetOpcode::G_FSINH:
689     return selectExtInst(ResVReg, ResType, I, CL::sinh, GL::Sinh);
690   case TargetOpcode::G_FTANH:
691     return selectExtInst(ResVReg, ResType, I, CL::tanh, GL::Tanh);
692 
693   case TargetOpcode::G_STRICT_FSQRT:
694   case TargetOpcode::G_FSQRT:
695     return selectExtInst(ResVReg, ResType, I, CL::sqrt, GL::Sqrt);
696 
697   case TargetOpcode::G_CTTZ:
698   case TargetOpcode::G_CTTZ_ZERO_UNDEF:
699     return selectExtInst(ResVReg, ResType, I, CL::ctz);
700   case TargetOpcode::G_CTLZ:
701   case TargetOpcode::G_CTLZ_ZERO_UNDEF:
702     return selectExtInst(ResVReg, ResType, I, CL::clz);
703 
704   case TargetOpcode::G_INTRINSIC_ROUND:
705     return selectExtInst(ResVReg, ResType, I, CL::round, GL::Round);
706   case TargetOpcode::G_INTRINSIC_ROUNDEVEN:
707     return selectExtInst(ResVReg, ResType, I, CL::rint, GL::RoundEven);
708   case TargetOpcode::G_INTRINSIC_TRUNC:
709     return selectExtInst(ResVReg, ResType, I, CL::trunc, GL::Trunc);
710   case TargetOpcode::G_FRINT:
711   case TargetOpcode::G_FNEARBYINT:
712     return selectExtInst(ResVReg, ResType, I, CL::rint, GL::RoundEven);
713 
714   case TargetOpcode::G_SMULH:
715     return selectExtInst(ResVReg, ResType, I, CL::s_mul_hi);
716   case TargetOpcode::G_UMULH:
717     return selectExtInst(ResVReg, ResType, I, CL::u_mul_hi);
718 
719   case TargetOpcode::G_SADDSAT:
720     return selectExtInst(ResVReg, ResType, I, CL::s_add_sat);
721   case TargetOpcode::G_UADDSAT:
722     return selectExtInst(ResVReg, ResType, I, CL::u_add_sat);
723   case TargetOpcode::G_SSUBSAT:
724     return selectExtInst(ResVReg, ResType, I, CL::s_sub_sat);
725   case TargetOpcode::G_USUBSAT:
726     return selectExtInst(ResVReg, ResType, I, CL::u_sub_sat);
727 
728   case TargetOpcode::G_UADDO:
729     return selectOverflowArith(ResVReg, ResType, I,
730                                ResType->getOpcode() == SPIRV::OpTypeVector
731                                    ? SPIRV::OpIAddCarryV
732                                    : SPIRV::OpIAddCarryS);
733   case TargetOpcode::G_USUBO:
734     return selectOverflowArith(ResVReg, ResType, I,
735                                ResType->getOpcode() == SPIRV::OpTypeVector
736                                    ? SPIRV::OpISubBorrowV
737                                    : SPIRV::OpISubBorrowS);
738   case TargetOpcode::G_UMULO:
739     return selectOverflowArith(ResVReg, ResType, I, SPIRV::OpUMulExtended);
740   case TargetOpcode::G_SMULO:
741     return selectOverflowArith(ResVReg, ResType, I, SPIRV::OpSMulExtended);
742 
743   case TargetOpcode::G_SEXT:
744     return selectExt(ResVReg, ResType, I, true);
745   case TargetOpcode::G_ANYEXT:
746   case TargetOpcode::G_ZEXT:
747     return selectExt(ResVReg, ResType, I, false);
748   case TargetOpcode::G_TRUNC:
749     return selectTrunc(ResVReg, ResType, I);
750   case TargetOpcode::G_FPTRUNC:
751   case TargetOpcode::G_FPEXT:
752     return selectUnOp(ResVReg, ResType, I, SPIRV::OpFConvert);
753 
754   case TargetOpcode::G_PTRTOINT:
755     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertPtrToU);
756   case TargetOpcode::G_INTTOPTR:
757     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertUToPtr);
758   case TargetOpcode::G_BITCAST:
759     return selectBitcast(ResVReg, ResType, I);
760   case TargetOpcode::G_ADDRSPACE_CAST:
761     return selectAddrSpaceCast(ResVReg, ResType, I);
762   case TargetOpcode::G_PTR_ADD: {
763     // Currently, we get G_PTR_ADD only applied to global variables.
764     assert(I.getOperand(1).isReg() && I.getOperand(2).isReg());
765     Register GV = I.getOperand(1).getReg();
766     MachineRegisterInfo::def_instr_iterator II = MRI->def_instr_begin(GV);
767     (void)II;
768     assert(((*II).getOpcode() == TargetOpcode::G_GLOBAL_VALUE ||
769             (*II).getOpcode() == TargetOpcode::COPY ||
770             (*II).getOpcode() == SPIRV::OpVariable) &&
771            isImm(I.getOperand(2), MRI));
772     // It may be the initialization of a global variable.
773     bool IsGVInit = false;
774     for (MachineRegisterInfo::use_instr_iterator
775              UseIt = MRI->use_instr_begin(I.getOperand(0).getReg()),
776              UseEnd = MRI->use_instr_end();
777          UseIt != UseEnd; UseIt = std::next(UseIt)) {
778       if ((*UseIt).getOpcode() == TargetOpcode::G_GLOBAL_VALUE ||
779           (*UseIt).getOpcode() == SPIRV::OpVariable) {
780         IsGVInit = true;
781         break;
782       }
783     }
784     MachineBasicBlock &BB = *I.getParent();
785     if (!IsGVInit) {
786       SPIRVType *GVType = GR.getSPIRVTypeForVReg(GV);
787       SPIRVType *GVPointeeType = GR.getPointeeType(GVType);
788       SPIRVType *ResPointeeType = GR.getPointeeType(ResType);
789       if (GVPointeeType && ResPointeeType && GVPointeeType != ResPointeeType) {
790         // Build a new virtual register that is associated with the required
791         // data type.
792         Register NewVReg = MRI->createGenericVirtualRegister(MRI->getType(GV));
793         MRI->setRegClass(NewVReg, MRI->getRegClass(GV));
794         //  Having a correctly typed base we are ready to build the actually
795         //  required GEP. It may not be a constant though, because all Operands
796         //  of OpSpecConstantOp is to originate from other const instructions,
797         //  and only the AccessChain named opcodes accept a global OpVariable
798         //  instruction. We can't use an AccessChain opcode because of the type
799         //  mismatch between result and base types.
800         if (!GR.isBitcastCompatible(ResType, GVType))
801           report_fatal_error(
802               "incompatible result and operand types in a bitcast");
803         Register ResTypeReg = GR.getSPIRVTypeID(ResType);
804         MachineInstrBuilder MIB =
805             BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpBitcast))
806                 .addDef(NewVReg)
807                 .addUse(ResTypeReg)
808                 .addUse(GV);
809         return MIB.constrainAllUses(TII, TRI, RBI) &&
810                BuildMI(BB, I, I.getDebugLoc(),
811                        TII.get(STI.isVulkanEnv()
812                                    ? SPIRV::OpInBoundsAccessChain
813                                    : SPIRV::OpInBoundsPtrAccessChain))
814                    .addDef(ResVReg)
815                    .addUse(ResTypeReg)
816                    .addUse(NewVReg)
817                    .addUse(I.getOperand(2).getReg())
818                    .constrainAllUses(TII, TRI, RBI);
819       } else {
820         return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
821             .addDef(ResVReg)
822             .addUse(GR.getSPIRVTypeID(ResType))
823             .addImm(
824                 static_cast<uint32_t>(SPIRV::Opcode::InBoundsPtrAccessChain))
825             .addUse(GV)
826             .addUse(I.getOperand(2).getReg())
827             .constrainAllUses(TII, TRI, RBI);
828       }
829     }
830     // It's possible to translate G_PTR_ADD to OpSpecConstantOp: either to
831     // initialize a global variable with a constant expression (e.g., the test
832     // case opencl/basic/progvar_prog_scope_init.ll), or for another use case
833     Register Idx = buildZerosVal(GR.getOrCreateSPIRVIntegerType(32, I, TII), I);
834     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
835                    .addDef(ResVReg)
836                    .addUse(GR.getSPIRVTypeID(ResType))
837                    .addImm(static_cast<uint32_t>(
838                        SPIRV::Opcode::InBoundsPtrAccessChain))
839                    .addUse(GV)
840                    .addUse(Idx)
841                    .addUse(I.getOperand(2).getReg());
842     return MIB.constrainAllUses(TII, TRI, RBI);
843   }
844 
845   case TargetOpcode::G_ATOMICRMW_OR:
846     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicOr);
847   case TargetOpcode::G_ATOMICRMW_ADD:
848     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicIAdd);
849   case TargetOpcode::G_ATOMICRMW_AND:
850     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicAnd);
851   case TargetOpcode::G_ATOMICRMW_MAX:
852     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicSMax);
853   case TargetOpcode::G_ATOMICRMW_MIN:
854     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicSMin);
855   case TargetOpcode::G_ATOMICRMW_SUB:
856     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicISub);
857   case TargetOpcode::G_ATOMICRMW_XOR:
858     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicXor);
859   case TargetOpcode::G_ATOMICRMW_UMAX:
860     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicUMax);
861   case TargetOpcode::G_ATOMICRMW_UMIN:
862     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicUMin);
863   case TargetOpcode::G_ATOMICRMW_XCHG:
864     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicExchange);
865   case TargetOpcode::G_ATOMIC_CMPXCHG:
866     return selectAtomicCmpXchg(ResVReg, ResType, I);
867 
868   case TargetOpcode::G_ATOMICRMW_FADD:
869     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFAddEXT);
870   case TargetOpcode::G_ATOMICRMW_FSUB:
871     // Translate G_ATOMICRMW_FSUB to OpAtomicFAddEXT with negative value operand
872     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFAddEXT,
873                            SPIRV::OpFNegate);
874   case TargetOpcode::G_ATOMICRMW_FMIN:
875     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFMinEXT);
876   case TargetOpcode::G_ATOMICRMW_FMAX:
877     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFMaxEXT);
878 
879   case TargetOpcode::G_FENCE:
880     return selectFence(I);
881 
882   case TargetOpcode::G_STACKSAVE:
883     return selectStackSave(ResVReg, ResType, I);
884   case TargetOpcode::G_STACKRESTORE:
885     return selectStackRestore(I);
886 
887   case TargetOpcode::G_UNMERGE_VALUES:
888     return selectUnmergeValues(I);
889 
890   // Discard gen opcodes for intrinsics which we do not expect to actually
891   // represent code after lowering or intrinsics which are not implemented but
892   // should not crash when found in a customer's LLVM IR input.
893   case TargetOpcode::G_TRAP:
894   case TargetOpcode::G_DEBUGTRAP:
895   case TargetOpcode::G_UBSANTRAP:
896   case TargetOpcode::DBG_LABEL:
897     return true;
898 
899   default:
900     return false;
901   }
902 }
903 
904 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
905                                              const SPIRVType *ResType,
906                                              MachineInstr &I,
907                                              GL::GLSLExtInst GLInst) const {
908   return selectExtInst(ResVReg, ResType, I,
909                        {{SPIRV::InstructionSet::GLSL_std_450, GLInst}});
910 }
911 
912 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
913                                              const SPIRVType *ResType,
914                                              MachineInstr &I,
915                                              CL::OpenCLExtInst CLInst) const {
916   return selectExtInst(ResVReg, ResType, I,
917                        {{SPIRV::InstructionSet::OpenCL_std, CLInst}});
918 }
919 
920 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
921                                              const SPIRVType *ResType,
922                                              MachineInstr &I,
923                                              CL::OpenCLExtInst CLInst,
924                                              GL::GLSLExtInst GLInst) const {
925   ExtInstList ExtInsts = {{SPIRV::InstructionSet::OpenCL_std, CLInst},
926                           {SPIRV::InstructionSet::GLSL_std_450, GLInst}};
927   return selectExtInst(ResVReg, ResType, I, ExtInsts);
928 }
929 
930 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
931                                              const SPIRVType *ResType,
932                                              MachineInstr &I,
933                                              const ExtInstList &Insts) const {
934 
935   for (const auto &Ex : Insts) {
936     SPIRV::InstructionSet::InstructionSet Set = Ex.first;
937     uint32_t Opcode = Ex.second;
938     if (STI.canUseExtInstSet(Set)) {
939       MachineBasicBlock &BB = *I.getParent();
940       auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
941                      .addDef(ResVReg)
942                      .addUse(GR.getSPIRVTypeID(ResType))
943                      .addImm(static_cast<uint32_t>(Set))
944                      .addImm(Opcode);
945       const unsigned NumOps = I.getNumOperands();
946       unsigned Index = 1;
947       if (Index < NumOps &&
948           I.getOperand(Index).getType() ==
949               MachineOperand::MachineOperandType::MO_IntrinsicID)
950         Index = 2;
951       for (; Index < NumOps; ++Index)
952         MIB.add(I.getOperand(Index));
953       return MIB.constrainAllUses(TII, TRI, RBI);
954     }
955   }
956   return false;
957 }
958 
959 bool SPIRVInstructionSelector::selectOpWithSrcs(Register ResVReg,
960                                                 const SPIRVType *ResType,
961                                                 MachineInstr &I,
962                                                 std::vector<Register> Srcs,
963                                                 unsigned Opcode) const {
964   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
965                  .addDef(ResVReg)
966                  .addUse(GR.getSPIRVTypeID(ResType));
967   for (Register SReg : Srcs) {
968     MIB.addUse(SReg);
969   }
970   return MIB.constrainAllUses(TII, TRI, RBI);
971 }
972 
973 bool SPIRVInstructionSelector::selectUnOp(Register ResVReg,
974                                           const SPIRVType *ResType,
975                                           MachineInstr &I,
976                                           unsigned Opcode) const {
977   if (STI.isOpenCLEnv() && I.getOperand(1).isReg()) {
978     Register SrcReg = I.getOperand(1).getReg();
979     bool IsGV = false;
980     for (MachineRegisterInfo::def_instr_iterator DefIt =
981              MRI->def_instr_begin(SrcReg);
982          DefIt != MRI->def_instr_end(); DefIt = std::next(DefIt)) {
983       if ((*DefIt).getOpcode() == TargetOpcode::G_GLOBAL_VALUE) {
984         IsGV = true;
985         break;
986       }
987     }
988     if (IsGV) {
989       uint32_t SpecOpcode = 0;
990       switch (Opcode) {
991       case SPIRV::OpConvertPtrToU:
992         SpecOpcode = static_cast<uint32_t>(SPIRV::Opcode::ConvertPtrToU);
993         break;
994       case SPIRV::OpConvertUToPtr:
995         SpecOpcode = static_cast<uint32_t>(SPIRV::Opcode::ConvertUToPtr);
996         break;
997       }
998       if (SpecOpcode)
999         return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1000                        TII.get(SPIRV::OpSpecConstantOp))
1001             .addDef(ResVReg)
1002             .addUse(GR.getSPIRVTypeID(ResType))
1003             .addImm(SpecOpcode)
1004             .addUse(SrcReg)
1005             .constrainAllUses(TII, TRI, RBI);
1006     }
1007   }
1008   return selectOpWithSrcs(ResVReg, ResType, I, {I.getOperand(1).getReg()},
1009                           Opcode);
1010 }
1011 
1012 bool SPIRVInstructionSelector::selectBitcast(Register ResVReg,
1013                                              const SPIRVType *ResType,
1014                                              MachineInstr &I) const {
1015   Register OpReg = I.getOperand(1).getReg();
1016   SPIRVType *OpType = OpReg.isValid() ? GR.getSPIRVTypeForVReg(OpReg) : nullptr;
1017   if (!GR.isBitcastCompatible(ResType, OpType))
1018     report_fatal_error("incompatible result and operand types in a bitcast");
1019   return selectUnOp(ResVReg, ResType, I, SPIRV::OpBitcast);
1020 }
1021 
1022 static void addMemoryOperands(MachineMemOperand *MemOp,
1023                               MachineInstrBuilder &MIB) {
1024   uint32_t SpvMemOp = static_cast<uint32_t>(SPIRV::MemoryOperand::None);
1025   if (MemOp->isVolatile())
1026     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Volatile);
1027   if (MemOp->isNonTemporal())
1028     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Nontemporal);
1029   if (MemOp->getAlign().value())
1030     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Aligned);
1031 
1032   if (SpvMemOp != static_cast<uint32_t>(SPIRV::MemoryOperand::None)) {
1033     MIB.addImm(SpvMemOp);
1034     if (SpvMemOp & static_cast<uint32_t>(SPIRV::MemoryOperand::Aligned))
1035       MIB.addImm(MemOp->getAlign().value());
1036   }
1037 }
1038 
1039 static void addMemoryOperands(uint64_t Flags, MachineInstrBuilder &MIB) {
1040   uint32_t SpvMemOp = static_cast<uint32_t>(SPIRV::MemoryOperand::None);
1041   if (Flags & MachineMemOperand::Flags::MOVolatile)
1042     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Volatile);
1043   if (Flags & MachineMemOperand::Flags::MONonTemporal)
1044     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Nontemporal);
1045 
1046   if (SpvMemOp != static_cast<uint32_t>(SPIRV::MemoryOperand::None))
1047     MIB.addImm(SpvMemOp);
1048 }
1049 
1050 bool SPIRVInstructionSelector::selectLoad(Register ResVReg,
1051                                           const SPIRVType *ResType,
1052                                           MachineInstr &I) const {
1053   unsigned OpOffset = isa<GIntrinsic>(I) ? 1 : 0;
1054   Register Ptr = I.getOperand(1 + OpOffset).getReg();
1055 
1056   auto *PtrDef = getVRegDef(*MRI, Ptr);
1057   auto *IntPtrDef = dyn_cast<GIntrinsic>(PtrDef);
1058   if (IntPtrDef &&
1059       IntPtrDef->getIntrinsicID() == Intrinsic::spv_resource_getpointer) {
1060     Register ImageReg = IntPtrDef->getOperand(2).getReg();
1061     Register NewImageReg =
1062         MRI->createVirtualRegister(MRI->getRegClass(ImageReg));
1063     auto *ImageDef = cast<GIntrinsic>(getVRegDef(*MRI, ImageReg));
1064     if (!loadHandleBeforePosition(NewImageReg, GR.getSPIRVTypeForVReg(ImageReg),
1065                                   *ImageDef, I)) {
1066       return false;
1067     }
1068 
1069     Register IdxReg = IntPtrDef->getOperand(3).getReg();
1070     return generateImageRead(ResVReg, ResType, NewImageReg, IdxReg,
1071                              I.getDebugLoc(), I);
1072   }
1073 
1074   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
1075                  .addDef(ResVReg)
1076                  .addUse(GR.getSPIRVTypeID(ResType))
1077                  .addUse(Ptr);
1078   if (!I.getNumMemOperands()) {
1079     assert(I.getOpcode() == TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS ||
1080            I.getOpcode() ==
1081                TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS);
1082     addMemoryOperands(I.getOperand(2 + OpOffset).getImm(), MIB);
1083   } else {
1084     addMemoryOperands(*I.memoperands_begin(), MIB);
1085   }
1086   return MIB.constrainAllUses(TII, TRI, RBI);
1087 }
1088 
1089 bool SPIRVInstructionSelector::selectStore(MachineInstr &I) const {
1090   unsigned OpOffset = isa<GIntrinsic>(I) ? 1 : 0;
1091   Register StoreVal = I.getOperand(0 + OpOffset).getReg();
1092   Register Ptr = I.getOperand(1 + OpOffset).getReg();
1093 
1094   auto *PtrDef = getVRegDef(*MRI, Ptr);
1095   auto *IntPtrDef = dyn_cast<GIntrinsic>(PtrDef);
1096   if (IntPtrDef &&
1097       IntPtrDef->getIntrinsicID() == Intrinsic::spv_resource_getpointer) {
1098     Register ImageReg = IntPtrDef->getOperand(2).getReg();
1099     Register NewImageReg =
1100         MRI->createVirtualRegister(MRI->getRegClass(ImageReg));
1101     auto *ImageDef = cast<GIntrinsic>(getVRegDef(*MRI, ImageReg));
1102     if (!loadHandleBeforePosition(NewImageReg, GR.getSPIRVTypeForVReg(ImageReg),
1103                                   *ImageDef, I)) {
1104       return false;
1105     }
1106 
1107     Register IdxReg = IntPtrDef->getOperand(3).getReg();
1108     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1109                    TII.get(SPIRV::OpImageWrite))
1110         .addUse(NewImageReg)
1111         .addUse(IdxReg)
1112         .addUse(StoreVal)
1113         .constrainAllUses(TII, TRI, RBI);
1114   }
1115 
1116   MachineBasicBlock &BB = *I.getParent();
1117   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpStore))
1118                  .addUse(Ptr)
1119                  .addUse(StoreVal);
1120   if (!I.getNumMemOperands()) {
1121     assert(I.getOpcode() == TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS ||
1122            I.getOpcode() ==
1123                TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS);
1124     addMemoryOperands(I.getOperand(2 + OpOffset).getImm(), MIB);
1125   } else {
1126     addMemoryOperands(*I.memoperands_begin(), MIB);
1127   }
1128   return MIB.constrainAllUses(TII, TRI, RBI);
1129 }
1130 
1131 bool SPIRVInstructionSelector::selectStackSave(Register ResVReg,
1132                                                const SPIRVType *ResType,
1133                                                MachineInstr &I) const {
1134   if (!STI.canUseExtension(SPIRV::Extension::SPV_INTEL_variable_length_array))
1135     report_fatal_error(
1136         "llvm.stacksave intrinsic: this instruction requires the following "
1137         "SPIR-V extension: SPV_INTEL_variable_length_array",
1138         false);
1139   MachineBasicBlock &BB = *I.getParent();
1140   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSaveMemoryINTEL))
1141       .addDef(ResVReg)
1142       .addUse(GR.getSPIRVTypeID(ResType))
1143       .constrainAllUses(TII, TRI, RBI);
1144 }
1145 
1146 bool SPIRVInstructionSelector::selectStackRestore(MachineInstr &I) const {
1147   if (!STI.canUseExtension(SPIRV::Extension::SPV_INTEL_variable_length_array))
1148     report_fatal_error(
1149         "llvm.stackrestore intrinsic: this instruction requires the following "
1150         "SPIR-V extension: SPV_INTEL_variable_length_array",
1151         false);
1152   if (!I.getOperand(0).isReg())
1153     return false;
1154   MachineBasicBlock &BB = *I.getParent();
1155   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpRestoreMemoryINTEL))
1156       .addUse(I.getOperand(0).getReg())
1157       .constrainAllUses(TII, TRI, RBI);
1158 }
1159 
1160 bool SPIRVInstructionSelector::selectMemOperation(Register ResVReg,
1161                                                   MachineInstr &I) const {
1162   MachineBasicBlock &BB = *I.getParent();
1163   Register SrcReg = I.getOperand(1).getReg();
1164   bool Result = true;
1165   if (I.getOpcode() == TargetOpcode::G_MEMSET) {
1166     assert(I.getOperand(1).isReg() && I.getOperand(2).isReg());
1167     unsigned Val = getIConstVal(I.getOperand(1).getReg(), MRI);
1168     unsigned Num = getIConstVal(I.getOperand(2).getReg(), MRI);
1169     SPIRVType *ValTy = GR.getOrCreateSPIRVIntegerType(8, I, TII);
1170     SPIRVType *ArrTy = GR.getOrCreateSPIRVArrayType(ValTy, Num, I, TII);
1171     Register Const = GR.getOrCreateConstIntArray(Val, Num, I, ArrTy, TII);
1172     SPIRVType *VarTy = GR.getOrCreateSPIRVPointerType(
1173         ArrTy, I, TII, SPIRV::StorageClass::UniformConstant);
1174     // TODO: check if we have such GV, add init, use buildGlobalVariable.
1175     Function &CurFunction = GR.CurMF->getFunction();
1176     Type *LLVMArrTy =
1177         ArrayType::get(IntegerType::get(CurFunction.getContext(), 8), Num);
1178     // Module takes ownership of the global var.
1179     GlobalVariable *GV = new GlobalVariable(*CurFunction.getParent(), LLVMArrTy,
1180                                             true, GlobalValue::InternalLinkage,
1181                                             Constant::getNullValue(LLVMArrTy));
1182     Register VarReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1183     GR.add(GV, GR.CurMF, VarReg);
1184     GR.addGlobalObject(GV, GR.CurMF, VarReg);
1185 
1186     Result &=
1187         BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpVariable))
1188             .addDef(VarReg)
1189             .addUse(GR.getSPIRVTypeID(VarTy))
1190             .addImm(SPIRV::StorageClass::UniformConstant)
1191             .addUse(Const)
1192             .constrainAllUses(TII, TRI, RBI);
1193     buildOpDecorate(VarReg, I, TII, SPIRV::Decoration::Constant, {});
1194     SPIRVType *SourceTy = GR.getOrCreateSPIRVPointerType(
1195         ValTy, I, TII, SPIRV::StorageClass::UniformConstant);
1196     SrcReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1197     selectOpWithSrcs(SrcReg, SourceTy, I, {VarReg}, SPIRV::OpBitcast);
1198   }
1199   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCopyMemorySized))
1200                  .addUse(I.getOperand(0).getReg())
1201                  .addUse(SrcReg)
1202                  .addUse(I.getOperand(2).getReg());
1203   if (I.getNumMemOperands())
1204     addMemoryOperands(*I.memoperands_begin(), MIB);
1205   Result &= MIB.constrainAllUses(TII, TRI, RBI);
1206   if (ResVReg.isValid() && ResVReg != MIB->getOperand(0).getReg())
1207     Result &= BuildCOPY(ResVReg, MIB->getOperand(0).getReg(), I);
1208   return Result;
1209 }
1210 
1211 bool SPIRVInstructionSelector::selectAtomicRMW(Register ResVReg,
1212                                                const SPIRVType *ResType,
1213                                                MachineInstr &I,
1214                                                unsigned NewOpcode,
1215                                                unsigned NegateOpcode) const {
1216   bool Result = true;
1217   assert(I.hasOneMemOperand());
1218   const MachineMemOperand *MemOp = *I.memoperands_begin();
1219   uint32_t Scope = static_cast<uint32_t>(getMemScope(
1220       GR.CurMF->getFunction().getContext(), MemOp->getSyncScopeID()));
1221   auto ScopeConstant = buildI32Constant(Scope, I);
1222   Register ScopeReg = ScopeConstant.first;
1223   Result &= ScopeConstant.second;
1224 
1225   Register Ptr = I.getOperand(1).getReg();
1226   // TODO: Changed as it's implemented in the translator. See test/atomicrmw.ll
1227   // auto ScSem =
1228   // getMemSemanticsForStorageClass(GR.getPointerStorageClass(Ptr));
1229   AtomicOrdering AO = MemOp->getSuccessOrdering();
1230   uint32_t MemSem = static_cast<uint32_t>(getMemSemantics(AO));
1231   auto MemSemConstant = buildI32Constant(MemSem /*| ScSem*/, I);
1232   Register MemSemReg = MemSemConstant.first;
1233   Result &= MemSemConstant.second;
1234 
1235   Register ValueReg = I.getOperand(2).getReg();
1236   if (NegateOpcode != 0) {
1237     // Translation with negative value operand is requested
1238     Register TmpReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1239     Result &= selectOpWithSrcs(TmpReg, ResType, I, {ValueReg}, NegateOpcode);
1240     ValueReg = TmpReg;
1241   }
1242 
1243   return Result &&
1244          BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(NewOpcode))
1245              .addDef(ResVReg)
1246              .addUse(GR.getSPIRVTypeID(ResType))
1247              .addUse(Ptr)
1248              .addUse(ScopeReg)
1249              .addUse(MemSemReg)
1250              .addUse(ValueReg)
1251              .constrainAllUses(TII, TRI, RBI);
1252 }
1253 
1254 bool SPIRVInstructionSelector::selectUnmergeValues(MachineInstr &I) const {
1255   unsigned ArgI = I.getNumOperands() - 1;
1256   Register SrcReg =
1257       I.getOperand(ArgI).isReg() ? I.getOperand(ArgI).getReg() : Register(0);
1258   SPIRVType *DefType =
1259       SrcReg.isValid() ? GR.getSPIRVTypeForVReg(SrcReg) : nullptr;
1260   if (!DefType || DefType->getOpcode() != SPIRV::OpTypeVector)
1261     report_fatal_error(
1262         "cannot select G_UNMERGE_VALUES with a non-vector argument");
1263 
1264   SPIRVType *ScalarType =
1265       GR.getSPIRVTypeForVReg(DefType->getOperand(1).getReg());
1266   MachineBasicBlock &BB = *I.getParent();
1267   bool Res = false;
1268   for (unsigned i = 0; i < I.getNumDefs(); ++i) {
1269     Register ResVReg = I.getOperand(i).getReg();
1270     SPIRVType *ResType = GR.getSPIRVTypeForVReg(ResVReg);
1271     if (!ResType) {
1272       // There was no "assign type" actions, let's fix this now
1273       ResType = ScalarType;
1274       MRI->setRegClass(ResVReg, GR.getRegClass(ResType));
1275       MRI->setType(ResVReg, LLT::scalar(GR.getScalarOrVectorBitWidth(ResType)));
1276       GR.assignSPIRVTypeToVReg(ResType, ResVReg, *GR.CurMF);
1277     }
1278     auto MIB =
1279         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1280             .addDef(ResVReg)
1281             .addUse(GR.getSPIRVTypeID(ResType))
1282             .addUse(SrcReg)
1283             .addImm(static_cast<int64_t>(i));
1284     Res |= MIB.constrainAllUses(TII, TRI, RBI);
1285   }
1286   return Res;
1287 }
1288 
1289 bool SPIRVInstructionSelector::selectFence(MachineInstr &I) const {
1290   AtomicOrdering AO = AtomicOrdering(I.getOperand(0).getImm());
1291   uint32_t MemSem = static_cast<uint32_t>(getMemSemantics(AO));
1292   auto MemSemConstant = buildI32Constant(MemSem, I);
1293   Register MemSemReg = MemSemConstant.first;
1294   bool Result = MemSemConstant.second;
1295   SyncScope::ID Ord = SyncScope::ID(I.getOperand(1).getImm());
1296   uint32_t Scope = static_cast<uint32_t>(
1297       getMemScope(GR.CurMF->getFunction().getContext(), Ord));
1298   auto ScopeConstant = buildI32Constant(Scope, I);
1299   Register ScopeReg = ScopeConstant.first;
1300   Result &= ScopeConstant.second;
1301   MachineBasicBlock &BB = *I.getParent();
1302   return Result &&
1303          BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpMemoryBarrier))
1304              .addUse(ScopeReg)
1305              .addUse(MemSemReg)
1306              .constrainAllUses(TII, TRI, RBI);
1307 }
1308 
1309 bool SPIRVInstructionSelector::selectOverflowArith(Register ResVReg,
1310                                                    const SPIRVType *ResType,
1311                                                    MachineInstr &I,
1312                                                    unsigned Opcode) const {
1313   Type *ResTy = nullptr;
1314   StringRef ResName;
1315   if (!GR.findValueAttrs(&I, ResTy, ResName))
1316     report_fatal_error(
1317         "Not enough info to select the arithmetic with overflow instruction");
1318   if (!ResTy || !ResTy->isStructTy())
1319     report_fatal_error("Expect struct type result for the arithmetic "
1320                        "with overflow instruction");
1321   // "Result Type must be from OpTypeStruct. The struct must have two members,
1322   // and the two members must be the same type."
1323   Type *ResElemTy = cast<StructType>(ResTy)->getElementType(0);
1324   ResTy = StructType::get(ResElemTy, ResElemTy);
1325   // Build SPIR-V types and constant(s) if needed.
1326   MachineIRBuilder MIRBuilder(I);
1327   SPIRVType *StructType = GR.getOrCreateSPIRVType(
1328       ResTy, MIRBuilder, SPIRV::AccessQualifier::ReadWrite, false);
1329   assert(I.getNumDefs() > 1 && "Not enought operands");
1330   SPIRVType *BoolType = GR.getOrCreateSPIRVBoolType(I, TII);
1331   unsigned N = GR.getScalarOrVectorComponentCount(ResType);
1332   if (N > 1)
1333     BoolType = GR.getOrCreateSPIRVVectorType(BoolType, N, I, TII);
1334   Register BoolTypeReg = GR.getSPIRVTypeID(BoolType);
1335   Register ZeroReg = buildZerosVal(ResType, I);
1336   // A new virtual register to store the result struct.
1337   Register StructVReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1338   MRI->setRegClass(StructVReg, &SPIRV::IDRegClass);
1339   // Build the result name if needed.
1340   if (ResName.size() > 0)
1341     buildOpName(StructVReg, ResName, MIRBuilder);
1342   // Build the arithmetic with overflow instruction.
1343   MachineBasicBlock &BB = *I.getParent();
1344   auto MIB =
1345       BuildMI(BB, MIRBuilder.getInsertPt(), I.getDebugLoc(), TII.get(Opcode))
1346           .addDef(StructVReg)
1347           .addUse(GR.getSPIRVTypeID(StructType));
1348   for (unsigned i = I.getNumDefs(); i < I.getNumOperands(); ++i)
1349     MIB.addUse(I.getOperand(i).getReg());
1350   bool Result = MIB.constrainAllUses(TII, TRI, RBI);
1351   // Build instructions to extract fields of the instruction's result.
1352   // A new virtual register to store the higher part of the result struct.
1353   Register HigherVReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1354   MRI->setRegClass(HigherVReg, &SPIRV::iIDRegClass);
1355   for (unsigned i = 0; i < I.getNumDefs(); ++i) {
1356     auto MIB =
1357         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1358             .addDef(i == 1 ? HigherVReg : I.getOperand(i).getReg())
1359             .addUse(GR.getSPIRVTypeID(ResType))
1360             .addUse(StructVReg)
1361             .addImm(i);
1362     Result &= MIB.constrainAllUses(TII, TRI, RBI);
1363   }
1364   // Build boolean value from the higher part.
1365   return Result && BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpINotEqual))
1366                        .addDef(I.getOperand(1).getReg())
1367                        .addUse(BoolTypeReg)
1368                        .addUse(HigherVReg)
1369                        .addUse(ZeroReg)
1370                        .constrainAllUses(TII, TRI, RBI);
1371 }
1372 
1373 bool SPIRVInstructionSelector::selectAtomicCmpXchg(Register ResVReg,
1374                                                    const SPIRVType *ResType,
1375                                                    MachineInstr &I) const {
1376   bool Result = true;
1377   Register ScopeReg;
1378   Register MemSemEqReg;
1379   Register MemSemNeqReg;
1380   Register Ptr = I.getOperand(2).getReg();
1381   if (!isa<GIntrinsic>(I)) {
1382     assert(I.hasOneMemOperand());
1383     const MachineMemOperand *MemOp = *I.memoperands_begin();
1384     unsigned Scope = static_cast<uint32_t>(getMemScope(
1385         GR.CurMF->getFunction().getContext(), MemOp->getSyncScopeID()));
1386     auto ScopeConstant = buildI32Constant(Scope, I);
1387     ScopeReg = ScopeConstant.first;
1388     Result &= ScopeConstant.second;
1389 
1390     unsigned ScSem = static_cast<uint32_t>(
1391         getMemSemanticsForStorageClass(GR.getPointerStorageClass(Ptr)));
1392     AtomicOrdering AO = MemOp->getSuccessOrdering();
1393     unsigned MemSemEq = static_cast<uint32_t>(getMemSemantics(AO)) | ScSem;
1394     auto MemSemEqConstant = buildI32Constant(MemSemEq, I);
1395     MemSemEqReg = MemSemEqConstant.first;
1396     Result &= MemSemEqConstant.second;
1397     AtomicOrdering FO = MemOp->getFailureOrdering();
1398     unsigned MemSemNeq = static_cast<uint32_t>(getMemSemantics(FO)) | ScSem;
1399     if (MemSemEq == MemSemNeq)
1400       MemSemNeqReg = MemSemEqReg;
1401     else {
1402       auto MemSemNeqConstant = buildI32Constant(MemSemEq, I);
1403       MemSemNeqReg = MemSemNeqConstant.first;
1404       Result &= MemSemNeqConstant.second;
1405     }
1406   } else {
1407     ScopeReg = I.getOperand(5).getReg();
1408     MemSemEqReg = I.getOperand(6).getReg();
1409     MemSemNeqReg = I.getOperand(7).getReg();
1410   }
1411 
1412   Register Cmp = I.getOperand(3).getReg();
1413   Register Val = I.getOperand(4).getReg();
1414   SPIRVType *SpvValTy = GR.getSPIRVTypeForVReg(Val);
1415   Register ACmpRes = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1416   const DebugLoc &DL = I.getDebugLoc();
1417   Result &=
1418       BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpAtomicCompareExchange))
1419           .addDef(ACmpRes)
1420           .addUse(GR.getSPIRVTypeID(SpvValTy))
1421           .addUse(Ptr)
1422           .addUse(ScopeReg)
1423           .addUse(MemSemEqReg)
1424           .addUse(MemSemNeqReg)
1425           .addUse(Val)
1426           .addUse(Cmp)
1427           .constrainAllUses(TII, TRI, RBI);
1428   Register CmpSuccReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1429   SPIRVType *BoolTy = GR.getOrCreateSPIRVBoolType(I, TII);
1430   Result &= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpIEqual))
1431                 .addDef(CmpSuccReg)
1432                 .addUse(GR.getSPIRVTypeID(BoolTy))
1433                 .addUse(ACmpRes)
1434                 .addUse(Cmp)
1435                 .constrainAllUses(TII, TRI, RBI);
1436   Register TmpReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1437   Result &= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpCompositeInsert))
1438                 .addDef(TmpReg)
1439                 .addUse(GR.getSPIRVTypeID(ResType))
1440                 .addUse(ACmpRes)
1441                 .addUse(GR.getOrCreateUndef(I, ResType, TII))
1442                 .addImm(0)
1443                 .constrainAllUses(TII, TRI, RBI);
1444   return Result &&
1445          BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpCompositeInsert))
1446              .addDef(ResVReg)
1447              .addUse(GR.getSPIRVTypeID(ResType))
1448              .addUse(CmpSuccReg)
1449              .addUse(TmpReg)
1450              .addImm(1)
1451              .constrainAllUses(TII, TRI, RBI);
1452 }
1453 
1454 static bool isGenericCastablePtr(SPIRV::StorageClass::StorageClass SC) {
1455   switch (SC) {
1456   case SPIRV::StorageClass::Workgroup:
1457   case SPIRV::StorageClass::CrossWorkgroup:
1458   case SPIRV::StorageClass::Function:
1459     return true;
1460   default:
1461     return false;
1462   }
1463 }
1464 
1465 static bool isUSMStorageClass(SPIRV::StorageClass::StorageClass SC) {
1466   switch (SC) {
1467   case SPIRV::StorageClass::DeviceOnlyINTEL:
1468   case SPIRV::StorageClass::HostOnlyINTEL:
1469     return true;
1470   default:
1471     return false;
1472   }
1473 }
1474 
1475 // Returns true ResVReg is referred only from global vars and OpName's.
1476 static bool isASCastInGVar(MachineRegisterInfo *MRI, Register ResVReg) {
1477   bool IsGRef = false;
1478   bool IsAllowedRefs =
1479       std::all_of(MRI->use_instr_begin(ResVReg), MRI->use_instr_end(),
1480                   [&IsGRef](auto const &It) {
1481                     unsigned Opcode = It.getOpcode();
1482                     if (Opcode == SPIRV::OpConstantComposite ||
1483                         Opcode == SPIRV::OpVariable ||
1484                         isSpvIntrinsic(It, Intrinsic::spv_init_global))
1485                       return IsGRef = true;
1486                     return Opcode == SPIRV::OpName;
1487                   });
1488   return IsAllowedRefs && IsGRef;
1489 }
1490 
1491 Register SPIRVInstructionSelector::getUcharPtrTypeReg(
1492     MachineInstr &I, SPIRV::StorageClass::StorageClass SC) const {
1493   return GR.getSPIRVTypeID(GR.getOrCreateSPIRVPointerType(
1494       GR.getOrCreateSPIRVIntegerType(8, I, TII), I, TII, SC));
1495 }
1496 
1497 MachineInstrBuilder
1498 SPIRVInstructionSelector::buildSpecConstantOp(MachineInstr &I, Register Dest,
1499                                               Register Src, Register DestType,
1500                                               uint32_t Opcode) const {
1501   return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1502                  TII.get(SPIRV::OpSpecConstantOp))
1503       .addDef(Dest)
1504       .addUse(DestType)
1505       .addImm(Opcode)
1506       .addUse(Src);
1507 }
1508 
1509 MachineInstrBuilder
1510 SPIRVInstructionSelector::buildConstGenericPtr(MachineInstr &I, Register SrcPtr,
1511                                                SPIRVType *SrcPtrTy) const {
1512   SPIRVType *GenericPtrTy = GR.getOrCreateSPIRVPointerType(
1513       GR.getPointeeType(SrcPtrTy), I, TII, SPIRV::StorageClass::Generic);
1514   Register Tmp = MRI->createVirtualRegister(&SPIRV::pIDRegClass);
1515   MRI->setType(Tmp, LLT::pointer(storageClassToAddressSpace(
1516                                      SPIRV::StorageClass::Generic),
1517                                  GR.getPointerSize()));
1518   MachineFunction *MF = I.getParent()->getParent();
1519   GR.assignSPIRVTypeToVReg(GenericPtrTy, Tmp, *MF);
1520   MachineInstrBuilder MIB = buildSpecConstantOp(
1521       I, Tmp, SrcPtr, GR.getSPIRVTypeID(GenericPtrTy),
1522       static_cast<uint32_t>(SPIRV::Opcode::PtrCastToGeneric));
1523   GR.add(MIB.getInstr(), MF, Tmp);
1524   return MIB;
1525 }
1526 
1527 // In SPIR-V address space casting can only happen to and from the Generic
1528 // storage class. We can also only cast Workgroup, CrossWorkgroup, or Function
1529 // pointers to and from Generic pointers. As such, we can convert e.g. from
1530 // Workgroup to Function by going via a Generic pointer as an intermediary. All
1531 // other combinations can only be done by a bitcast, and are probably not safe.
1532 bool SPIRVInstructionSelector::selectAddrSpaceCast(Register ResVReg,
1533                                                    const SPIRVType *ResType,
1534                                                    MachineInstr &I) const {
1535   MachineBasicBlock &BB = *I.getParent();
1536   const DebugLoc &DL = I.getDebugLoc();
1537 
1538   Register SrcPtr = I.getOperand(1).getReg();
1539   SPIRVType *SrcPtrTy = GR.getSPIRVTypeForVReg(SrcPtr);
1540 
1541   // don't generate a cast for a null that may be represented by OpTypeInt
1542   if (SrcPtrTy->getOpcode() != SPIRV::OpTypePointer ||
1543       ResType->getOpcode() != SPIRV::OpTypePointer)
1544     return BuildCOPY(ResVReg, SrcPtr, I);
1545 
1546   SPIRV::StorageClass::StorageClass SrcSC = GR.getPointerStorageClass(SrcPtrTy);
1547   SPIRV::StorageClass::StorageClass DstSC = GR.getPointerStorageClass(ResType);
1548 
1549   if (isASCastInGVar(MRI, ResVReg)) {
1550     // AddrSpaceCast uses within OpVariable and OpConstantComposite instructions
1551     // are expressed by OpSpecConstantOp with an Opcode.
1552     // TODO: maybe insert a check whether the Kernel capability was declared and
1553     // so PtrCastToGeneric/GenericCastToPtr are available.
1554     unsigned SpecOpcode =
1555         DstSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(SrcSC)
1556             ? static_cast<uint32_t>(SPIRV::Opcode::PtrCastToGeneric)
1557             : (SrcSC == SPIRV::StorageClass::Generic &&
1558                        isGenericCastablePtr(DstSC)
1559                    ? static_cast<uint32_t>(SPIRV::Opcode::GenericCastToPtr)
1560                    : 0);
1561     // TODO: OpConstantComposite expects i8*, so we are forced to forget a
1562     // correct value of ResType and use general i8* instead. Maybe this should
1563     // be addressed in the emit-intrinsic step to infer a correct
1564     // OpConstantComposite type.
1565     if (SpecOpcode) {
1566       return buildSpecConstantOp(I, ResVReg, SrcPtr,
1567                                  getUcharPtrTypeReg(I, DstSC), SpecOpcode)
1568           .constrainAllUses(TII, TRI, RBI);
1569     } else if (isGenericCastablePtr(SrcSC) && isGenericCastablePtr(DstSC)) {
1570       MachineInstrBuilder MIB = buildConstGenericPtr(I, SrcPtr, SrcPtrTy);
1571       return MIB.constrainAllUses(TII, TRI, RBI) &&
1572              buildSpecConstantOp(
1573                  I, ResVReg, MIB->getOperand(0).getReg(),
1574                  getUcharPtrTypeReg(I, DstSC),
1575                  static_cast<uint32_t>(SPIRV::Opcode::GenericCastToPtr))
1576                  .constrainAllUses(TII, TRI, RBI);
1577     }
1578   }
1579 
1580   // don't generate a cast between identical storage classes
1581   if (SrcSC == DstSC)
1582     return BuildCOPY(ResVReg, SrcPtr, I);
1583 
1584   if ((SrcSC == SPIRV::StorageClass::Function &&
1585        DstSC == SPIRV::StorageClass::Private) ||
1586       (DstSC == SPIRV::StorageClass::Function &&
1587        SrcSC == SPIRV::StorageClass::Private))
1588     return BuildCOPY(ResVReg, SrcPtr, I);
1589 
1590   // Casting from an eligible pointer to Generic.
1591   if (DstSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(SrcSC))
1592     return selectUnOp(ResVReg, ResType, I, SPIRV::OpPtrCastToGeneric);
1593   // Casting from Generic to an eligible pointer.
1594   if (SrcSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(DstSC))
1595     return selectUnOp(ResVReg, ResType, I, SPIRV::OpGenericCastToPtr);
1596   // Casting between 2 eligible pointers using Generic as an intermediary.
1597   if (isGenericCastablePtr(SrcSC) && isGenericCastablePtr(DstSC)) {
1598     Register Tmp = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1599     SPIRVType *GenericPtrTy = GR.getOrCreateSPIRVPointerType(
1600         GR.getPointeeType(SrcPtrTy), I, TII, SPIRV::StorageClass::Generic);
1601     bool Result = BuildMI(BB, I, DL, TII.get(SPIRV::OpPtrCastToGeneric))
1602                       .addDef(Tmp)
1603                       .addUse(GR.getSPIRVTypeID(GenericPtrTy))
1604                       .addUse(SrcPtr)
1605                       .constrainAllUses(TII, TRI, RBI);
1606     return Result && BuildMI(BB, I, DL, TII.get(SPIRV::OpGenericCastToPtr))
1607                          .addDef(ResVReg)
1608                          .addUse(GR.getSPIRVTypeID(ResType))
1609                          .addUse(Tmp)
1610                          .constrainAllUses(TII, TRI, RBI);
1611   }
1612 
1613   // Check if instructions from the SPV_INTEL_usm_storage_classes extension may
1614   // be applied
1615   if (isUSMStorageClass(SrcSC) && DstSC == SPIRV::StorageClass::CrossWorkgroup)
1616     return selectUnOp(ResVReg, ResType, I,
1617                       SPIRV::OpPtrCastToCrossWorkgroupINTEL);
1618   if (SrcSC == SPIRV::StorageClass::CrossWorkgroup && isUSMStorageClass(DstSC))
1619     return selectUnOp(ResVReg, ResType, I,
1620                       SPIRV::OpCrossWorkgroupCastToPtrINTEL);
1621   if (isUSMStorageClass(SrcSC) && DstSC == SPIRV::StorageClass::Generic)
1622     return selectUnOp(ResVReg, ResType, I, SPIRV::OpPtrCastToGeneric);
1623   if (SrcSC == SPIRV::StorageClass::Generic && isUSMStorageClass(DstSC))
1624     return selectUnOp(ResVReg, ResType, I, SPIRV::OpGenericCastToPtr);
1625 
1626   // Bitcast for pointers requires that the address spaces must match
1627   return false;
1628 }
1629 
1630 static unsigned getFCmpOpcode(unsigned PredNum) {
1631   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1632   switch (Pred) {
1633   case CmpInst::FCMP_OEQ:
1634     return SPIRV::OpFOrdEqual;
1635   case CmpInst::FCMP_OGE:
1636     return SPIRV::OpFOrdGreaterThanEqual;
1637   case CmpInst::FCMP_OGT:
1638     return SPIRV::OpFOrdGreaterThan;
1639   case CmpInst::FCMP_OLE:
1640     return SPIRV::OpFOrdLessThanEqual;
1641   case CmpInst::FCMP_OLT:
1642     return SPIRV::OpFOrdLessThan;
1643   case CmpInst::FCMP_ONE:
1644     return SPIRV::OpFOrdNotEqual;
1645   case CmpInst::FCMP_ORD:
1646     return SPIRV::OpOrdered;
1647   case CmpInst::FCMP_UEQ:
1648     return SPIRV::OpFUnordEqual;
1649   case CmpInst::FCMP_UGE:
1650     return SPIRV::OpFUnordGreaterThanEqual;
1651   case CmpInst::FCMP_UGT:
1652     return SPIRV::OpFUnordGreaterThan;
1653   case CmpInst::FCMP_ULE:
1654     return SPIRV::OpFUnordLessThanEqual;
1655   case CmpInst::FCMP_ULT:
1656     return SPIRV::OpFUnordLessThan;
1657   case CmpInst::FCMP_UNE:
1658     return SPIRV::OpFUnordNotEqual;
1659   case CmpInst::FCMP_UNO:
1660     return SPIRV::OpUnordered;
1661   default:
1662     llvm_unreachable("Unknown predicate type for FCmp");
1663   }
1664 }
1665 
1666 static unsigned getICmpOpcode(unsigned PredNum) {
1667   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1668   switch (Pred) {
1669   case CmpInst::ICMP_EQ:
1670     return SPIRV::OpIEqual;
1671   case CmpInst::ICMP_NE:
1672     return SPIRV::OpINotEqual;
1673   case CmpInst::ICMP_SGE:
1674     return SPIRV::OpSGreaterThanEqual;
1675   case CmpInst::ICMP_SGT:
1676     return SPIRV::OpSGreaterThan;
1677   case CmpInst::ICMP_SLE:
1678     return SPIRV::OpSLessThanEqual;
1679   case CmpInst::ICMP_SLT:
1680     return SPIRV::OpSLessThan;
1681   case CmpInst::ICMP_UGE:
1682     return SPIRV::OpUGreaterThanEqual;
1683   case CmpInst::ICMP_UGT:
1684     return SPIRV::OpUGreaterThan;
1685   case CmpInst::ICMP_ULE:
1686     return SPIRV::OpULessThanEqual;
1687   case CmpInst::ICMP_ULT:
1688     return SPIRV::OpULessThan;
1689   default:
1690     llvm_unreachable("Unknown predicate type for ICmp");
1691   }
1692 }
1693 
1694 static unsigned getPtrCmpOpcode(unsigned Pred) {
1695   switch (static_cast<CmpInst::Predicate>(Pred)) {
1696   case CmpInst::ICMP_EQ:
1697     return SPIRV::OpPtrEqual;
1698   case CmpInst::ICMP_NE:
1699     return SPIRV::OpPtrNotEqual;
1700   default:
1701     llvm_unreachable("Unknown predicate type for pointer comparison");
1702   }
1703 }
1704 
1705 // Return the logical operation, or abort if none exists.
1706 static unsigned getBoolCmpOpcode(unsigned PredNum) {
1707   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1708   switch (Pred) {
1709   case CmpInst::ICMP_EQ:
1710     return SPIRV::OpLogicalEqual;
1711   case CmpInst::ICMP_NE:
1712     return SPIRV::OpLogicalNotEqual;
1713   default:
1714     llvm_unreachable("Unknown predicate type for Bool comparison");
1715   }
1716 }
1717 
1718 static APFloat getZeroFP(const Type *LLVMFloatTy) {
1719   if (!LLVMFloatTy)
1720     return APFloat::getZero(APFloat::IEEEsingle());
1721   switch (LLVMFloatTy->getScalarType()->getTypeID()) {
1722   case Type::HalfTyID:
1723     return APFloat::getZero(APFloat::IEEEhalf());
1724   default:
1725   case Type::FloatTyID:
1726     return APFloat::getZero(APFloat::IEEEsingle());
1727   case Type::DoubleTyID:
1728     return APFloat::getZero(APFloat::IEEEdouble());
1729   }
1730 }
1731 
1732 static APFloat getOneFP(const Type *LLVMFloatTy) {
1733   if (!LLVMFloatTy)
1734     return APFloat::getOne(APFloat::IEEEsingle());
1735   switch (LLVMFloatTy->getScalarType()->getTypeID()) {
1736   case Type::HalfTyID:
1737     return APFloat::getOne(APFloat::IEEEhalf());
1738   default:
1739   case Type::FloatTyID:
1740     return APFloat::getOne(APFloat::IEEEsingle());
1741   case Type::DoubleTyID:
1742     return APFloat::getOne(APFloat::IEEEdouble());
1743   }
1744 }
1745 
1746 bool SPIRVInstructionSelector::selectAnyOrAll(Register ResVReg,
1747                                               const SPIRVType *ResType,
1748                                               MachineInstr &I,
1749                                               unsigned OpAnyOrAll) const {
1750   assert(I.getNumOperands() == 3);
1751   assert(I.getOperand(2).isReg());
1752   MachineBasicBlock &BB = *I.getParent();
1753   Register InputRegister = I.getOperand(2).getReg();
1754   SPIRVType *InputType = GR.getSPIRVTypeForVReg(InputRegister);
1755 
1756   if (!InputType)
1757     report_fatal_error("Input Type could not be determined.");
1758 
1759   bool IsBoolTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeBool);
1760   bool IsVectorTy = InputType->getOpcode() == SPIRV::OpTypeVector;
1761   if (IsBoolTy && !IsVectorTy) {
1762     assert(ResVReg == I.getOperand(0).getReg());
1763     return BuildCOPY(ResVReg, InputRegister, I);
1764   }
1765 
1766   bool IsFloatTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeFloat);
1767   unsigned SpirvNotEqualId =
1768       IsFloatTy ? SPIRV::OpFOrdNotEqual : SPIRV::OpINotEqual;
1769   SPIRVType *SpvBoolScalarTy = GR.getOrCreateSPIRVBoolType(I, TII);
1770   SPIRVType *SpvBoolTy = SpvBoolScalarTy;
1771   Register NotEqualReg = ResVReg;
1772 
1773   if (IsVectorTy) {
1774     NotEqualReg = IsBoolTy ? InputRegister
1775                            : MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1776     const unsigned NumElts = InputType->getOperand(2).getImm();
1777     SpvBoolTy = GR.getOrCreateSPIRVVectorType(SpvBoolTy, NumElts, I, TII);
1778   }
1779 
1780   bool Result = true;
1781   if (!IsBoolTy) {
1782     Register ConstZeroReg =
1783         IsFloatTy ? buildZerosValF(InputType, I) : buildZerosVal(InputType, I);
1784 
1785     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SpirvNotEqualId))
1786                   .addDef(NotEqualReg)
1787                   .addUse(GR.getSPIRVTypeID(SpvBoolTy))
1788                   .addUse(InputRegister)
1789                   .addUse(ConstZeroReg)
1790                   .constrainAllUses(TII, TRI, RBI);
1791   }
1792 
1793   if (!IsVectorTy)
1794     return Result;
1795 
1796   return Result && BuildMI(BB, I, I.getDebugLoc(), TII.get(OpAnyOrAll))
1797                        .addDef(ResVReg)
1798                        .addUse(GR.getSPIRVTypeID(SpvBoolScalarTy))
1799                        .addUse(NotEqualReg)
1800                        .constrainAllUses(TII, TRI, RBI);
1801 }
1802 
1803 bool SPIRVInstructionSelector::selectAll(Register ResVReg,
1804                                          const SPIRVType *ResType,
1805                                          MachineInstr &I) const {
1806   return selectAnyOrAll(ResVReg, ResType, I, SPIRV::OpAll);
1807 }
1808 
1809 bool SPIRVInstructionSelector::selectAny(Register ResVReg,
1810                                          const SPIRVType *ResType,
1811                                          MachineInstr &I) const {
1812   return selectAnyOrAll(ResVReg, ResType, I, SPIRV::OpAny);
1813 }
1814 
1815 // Select the OpDot instruction for the given float dot
1816 bool SPIRVInstructionSelector::selectFloatDot(Register ResVReg,
1817                                               const SPIRVType *ResType,
1818                                               MachineInstr &I) const {
1819   assert(I.getNumOperands() == 4);
1820   assert(I.getOperand(2).isReg());
1821   assert(I.getOperand(3).isReg());
1822 
1823   [[maybe_unused]] SPIRVType *VecType =
1824       GR.getSPIRVTypeForVReg(I.getOperand(2).getReg());
1825 
1826   assert(VecType->getOpcode() == SPIRV::OpTypeVector &&
1827          GR.getScalarOrVectorComponentCount(VecType) > 1 &&
1828          "dot product requires a vector of at least 2 components");
1829 
1830   [[maybe_unused]] SPIRVType *EltType =
1831       GR.getSPIRVTypeForVReg(VecType->getOperand(1).getReg());
1832 
1833   assert(EltType->getOpcode() == SPIRV::OpTypeFloat);
1834 
1835   MachineBasicBlock &BB = *I.getParent();
1836   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpDot))
1837       .addDef(ResVReg)
1838       .addUse(GR.getSPIRVTypeID(ResType))
1839       .addUse(I.getOperand(2).getReg())
1840       .addUse(I.getOperand(3).getReg())
1841       .constrainAllUses(TII, TRI, RBI);
1842 }
1843 
1844 bool SPIRVInstructionSelector::selectIntegerDot(Register ResVReg,
1845                                                 const SPIRVType *ResType,
1846                                                 MachineInstr &I,
1847                                                 bool Signed) const {
1848   assert(I.getNumOperands() == 4);
1849   assert(I.getOperand(2).isReg());
1850   assert(I.getOperand(3).isReg());
1851   MachineBasicBlock &BB = *I.getParent();
1852 
1853   auto DotOp = Signed ? SPIRV::OpSDot : SPIRV::OpUDot;
1854   return BuildMI(BB, I, I.getDebugLoc(), TII.get(DotOp))
1855       .addDef(ResVReg)
1856       .addUse(GR.getSPIRVTypeID(ResType))
1857       .addUse(I.getOperand(2).getReg())
1858       .addUse(I.getOperand(3).getReg())
1859       .constrainAllUses(TII, TRI, RBI);
1860 }
1861 
1862 // Since pre-1.6 SPIRV has no integer dot implementation,
1863 // expand by piecewise multiplying and adding the results
1864 bool SPIRVInstructionSelector::selectIntegerDotExpansion(
1865     Register ResVReg, const SPIRVType *ResType, MachineInstr &I) const {
1866   assert(I.getNumOperands() == 4);
1867   assert(I.getOperand(2).isReg());
1868   assert(I.getOperand(3).isReg());
1869   MachineBasicBlock &BB = *I.getParent();
1870 
1871   // Multiply the vectors, then sum the results
1872   Register Vec0 = I.getOperand(2).getReg();
1873   Register Vec1 = I.getOperand(3).getReg();
1874   Register TmpVec = MRI->createVirtualRegister(GR.getRegClass(ResType));
1875   SPIRVType *VecType = GR.getSPIRVTypeForVReg(Vec0);
1876 
1877   bool Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIMulV))
1878                     .addDef(TmpVec)
1879                     .addUse(GR.getSPIRVTypeID(VecType))
1880                     .addUse(Vec0)
1881                     .addUse(Vec1)
1882                     .constrainAllUses(TII, TRI, RBI);
1883 
1884   assert(VecType->getOpcode() == SPIRV::OpTypeVector &&
1885          GR.getScalarOrVectorComponentCount(VecType) > 1 &&
1886          "dot product requires a vector of at least 2 components");
1887 
1888   Register Res = MRI->createVirtualRegister(GR.getRegClass(ResType));
1889   Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1890                 .addDef(Res)
1891                 .addUse(GR.getSPIRVTypeID(ResType))
1892                 .addUse(TmpVec)
1893                 .addImm(0)
1894                 .constrainAllUses(TII, TRI, RBI);
1895 
1896   for (unsigned i = 1; i < GR.getScalarOrVectorComponentCount(VecType); i++) {
1897     Register Elt = MRI->createVirtualRegister(GR.getRegClass(ResType));
1898 
1899     Result &=
1900         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1901             .addDef(Elt)
1902             .addUse(GR.getSPIRVTypeID(ResType))
1903             .addUse(TmpVec)
1904             .addImm(i)
1905             .constrainAllUses(TII, TRI, RBI);
1906 
1907     Register Sum = i < GR.getScalarOrVectorComponentCount(VecType) - 1
1908                        ? MRI->createVirtualRegister(GR.getRegClass(ResType))
1909                        : ResVReg;
1910 
1911     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIAddS))
1912                   .addDef(Sum)
1913                   .addUse(GR.getSPIRVTypeID(ResType))
1914                   .addUse(Res)
1915                   .addUse(Elt)
1916                   .constrainAllUses(TII, TRI, RBI);
1917     Res = Sum;
1918   }
1919 
1920   return Result;
1921 }
1922 
1923 template <bool Signed>
1924 bool SPIRVInstructionSelector::selectDot4AddPacked(Register ResVReg,
1925                                                    const SPIRVType *ResType,
1926                                                    MachineInstr &I) const {
1927   assert(I.getNumOperands() == 5);
1928   assert(I.getOperand(2).isReg());
1929   assert(I.getOperand(3).isReg());
1930   assert(I.getOperand(4).isReg());
1931   MachineBasicBlock &BB = *I.getParent();
1932 
1933   auto DotOp = Signed ? SPIRV::OpSDot : SPIRV::OpUDot;
1934   Register Dot = MRI->createVirtualRegister(GR.getRegClass(ResType));
1935   bool Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(DotOp))
1936                     .addDef(Dot)
1937                     .addUse(GR.getSPIRVTypeID(ResType))
1938                     .addUse(I.getOperand(2).getReg())
1939                     .addUse(I.getOperand(3).getReg())
1940                     .constrainAllUses(TII, TRI, RBI);
1941 
1942   return Result && BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIAddS))
1943                        .addDef(ResVReg)
1944                        .addUse(GR.getSPIRVTypeID(ResType))
1945                        .addUse(Dot)
1946                        .addUse(I.getOperand(4).getReg())
1947                        .constrainAllUses(TII, TRI, RBI);
1948 }
1949 
1950 // Since pre-1.6 SPIRV has no DotProductInput4x8BitPacked implementation,
1951 // extract the elements of the packed inputs, multiply them and add the result
1952 // to the accumulator.
1953 template <bool Signed>
1954 bool SPIRVInstructionSelector::selectDot4AddPackedExpansion(
1955     Register ResVReg, const SPIRVType *ResType, MachineInstr &I) const {
1956   assert(I.getNumOperands() == 5);
1957   assert(I.getOperand(2).isReg());
1958   assert(I.getOperand(3).isReg());
1959   assert(I.getOperand(4).isReg());
1960   MachineBasicBlock &BB = *I.getParent();
1961 
1962   bool Result = true;
1963 
1964   // Acc = C
1965   Register Acc = I.getOperand(4).getReg();
1966   SPIRVType *EltType = GR.getOrCreateSPIRVIntegerType(8, I, TII);
1967   auto ExtractOp =
1968       Signed ? SPIRV::OpBitFieldSExtract : SPIRV::OpBitFieldUExtract;
1969 
1970   // Extract the i8 element, multiply and add it to the accumulator
1971   for (unsigned i = 0; i < 4; i++) {
1972     // A[i]
1973     Register AElt = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1974     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(ExtractOp))
1975                   .addDef(AElt)
1976                   .addUse(GR.getSPIRVTypeID(ResType))
1977                   .addUse(I.getOperand(2).getReg())
1978                   .addUse(GR.getOrCreateConstInt(i * 8, I, EltType, TII))
1979                   .addUse(GR.getOrCreateConstInt(8, I, EltType, TII))
1980                   .constrainAllUses(TII, TRI, RBI);
1981 
1982     // B[i]
1983     Register BElt = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1984     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(ExtractOp))
1985                   .addDef(BElt)
1986                   .addUse(GR.getSPIRVTypeID(ResType))
1987                   .addUse(I.getOperand(3).getReg())
1988                   .addUse(GR.getOrCreateConstInt(i * 8, I, EltType, TII))
1989                   .addUse(GR.getOrCreateConstInt(8, I, EltType, TII))
1990                   .constrainAllUses(TII, TRI, RBI);
1991 
1992     // A[i] * B[i]
1993     Register Mul = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1994     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIMulS))
1995                   .addDef(Mul)
1996                   .addUse(GR.getSPIRVTypeID(ResType))
1997                   .addUse(AElt)
1998                   .addUse(BElt)
1999                   .constrainAllUses(TII, TRI, RBI);
2000 
2001     // Discard 24 highest-bits so that stored i32 register is i8 equivalent
2002     Register MaskMul = MRI->createVirtualRegister(&SPIRV::IDRegClass);
2003     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(ExtractOp))
2004                   .addDef(MaskMul)
2005                   .addUse(GR.getSPIRVTypeID(ResType))
2006                   .addUse(Mul)
2007                   .addUse(GR.getOrCreateConstInt(0, I, EltType, TII))
2008                   .addUse(GR.getOrCreateConstInt(8, I, EltType, TII))
2009                   .constrainAllUses(TII, TRI, RBI);
2010 
2011     // Acc = Acc + A[i] * B[i]
2012     Register Sum =
2013         i < 3 ? MRI->createVirtualRegister(&SPIRV::IDRegClass) : ResVReg;
2014     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIAddS))
2015                   .addDef(Sum)
2016                   .addUse(GR.getSPIRVTypeID(ResType))
2017                   .addUse(Acc)
2018                   .addUse(MaskMul)
2019                   .constrainAllUses(TII, TRI, RBI);
2020 
2021     Acc = Sum;
2022   }
2023 
2024   return Result;
2025 }
2026 
2027 /// Transform saturate(x) to clamp(x, 0.0f, 1.0f) as SPIRV
2028 /// does not have a saturate builtin.
2029 bool SPIRVInstructionSelector::selectSaturate(Register ResVReg,
2030                                               const SPIRVType *ResType,
2031                                               MachineInstr &I) const {
2032   assert(I.getNumOperands() == 3);
2033   assert(I.getOperand(2).isReg());
2034   MachineBasicBlock &BB = *I.getParent();
2035   Register VZero = buildZerosValF(ResType, I);
2036   Register VOne = buildOnesValF(ResType, I);
2037 
2038   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
2039       .addDef(ResVReg)
2040       .addUse(GR.getSPIRVTypeID(ResType))
2041       .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
2042       .addImm(GL::FClamp)
2043       .addUse(I.getOperand(2).getReg())
2044       .addUse(VZero)
2045       .addUse(VOne)
2046       .constrainAllUses(TII, TRI, RBI);
2047 }
2048 
2049 bool SPIRVInstructionSelector::selectSign(Register ResVReg,
2050                                           const SPIRVType *ResType,
2051                                           MachineInstr &I) const {
2052   assert(I.getNumOperands() == 3);
2053   assert(I.getOperand(2).isReg());
2054   MachineBasicBlock &BB = *I.getParent();
2055   Register InputRegister = I.getOperand(2).getReg();
2056   SPIRVType *InputType = GR.getSPIRVTypeForVReg(InputRegister);
2057   auto &DL = I.getDebugLoc();
2058 
2059   if (!InputType)
2060     report_fatal_error("Input Type could not be determined.");
2061 
2062   bool IsFloatTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeFloat);
2063 
2064   unsigned SignBitWidth = GR.getScalarOrVectorBitWidth(InputType);
2065   unsigned ResBitWidth = GR.getScalarOrVectorBitWidth(ResType);
2066 
2067   bool NeedsConversion = IsFloatTy || SignBitWidth != ResBitWidth;
2068 
2069   auto SignOpcode = IsFloatTy ? GL::FSign : GL::SSign;
2070   Register SignReg = NeedsConversion
2071                          ? MRI->createVirtualRegister(&SPIRV::IDRegClass)
2072                          : ResVReg;
2073 
2074   bool Result =
2075       BuildMI(BB, I, DL, TII.get(SPIRV::OpExtInst))
2076           .addDef(SignReg)
2077           .addUse(GR.getSPIRVTypeID(InputType))
2078           .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
2079           .addImm(SignOpcode)
2080           .addUse(InputRegister)
2081           .constrainAllUses(TII, TRI, RBI);
2082 
2083   if (NeedsConversion) {
2084     auto ConvertOpcode = IsFloatTy ? SPIRV::OpConvertFToS : SPIRV::OpSConvert;
2085     Result &= BuildMI(*I.getParent(), I, DL, TII.get(ConvertOpcode))
2086                   .addDef(ResVReg)
2087                   .addUse(GR.getSPIRVTypeID(ResType))
2088                   .addUse(SignReg)
2089                   .constrainAllUses(TII, TRI, RBI);
2090   }
2091 
2092   return Result;
2093 }
2094 
2095 bool SPIRVInstructionSelector::selectWaveOpInst(Register ResVReg,
2096                                                 const SPIRVType *ResType,
2097                                                 MachineInstr &I,
2098                                                 unsigned Opcode) const {
2099   MachineBasicBlock &BB = *I.getParent();
2100   SPIRVType *IntTy = GR.getOrCreateSPIRVIntegerType(32, I, TII);
2101 
2102   auto BMI = BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2103                  .addDef(ResVReg)
2104                  .addUse(GR.getSPIRVTypeID(ResType))
2105                  .addUse(GR.getOrCreateConstInt(SPIRV::Scope::Subgroup, I,
2106                                                 IntTy, TII));
2107 
2108   for (unsigned J = 2; J < I.getNumOperands(); J++) {
2109     BMI.addUse(I.getOperand(J).getReg());
2110   }
2111 
2112   return BMI.constrainAllUses(TII, TRI, RBI);
2113 }
2114 
2115 bool SPIRVInstructionSelector::selectWaveActiveCountBits(
2116     Register ResVReg, const SPIRVType *ResType, MachineInstr &I) const {
2117 
2118   SPIRVType *IntTy = GR.getOrCreateSPIRVIntegerType(32, I, TII);
2119   SPIRVType *BallotType = GR.getOrCreateSPIRVVectorType(IntTy, 4, I, TII);
2120   Register BallotReg = MRI->createVirtualRegister(GR.getRegClass(BallotType));
2121   bool Result = selectWaveOpInst(BallotReg, BallotType, I,
2122                                  SPIRV::OpGroupNonUniformBallot);
2123 
2124   MachineBasicBlock &BB = *I.getParent();
2125   Result &=
2126       BuildMI(BB, I, I.getDebugLoc(),
2127               TII.get(SPIRV::OpGroupNonUniformBallotBitCount))
2128           .addDef(ResVReg)
2129           .addUse(GR.getSPIRVTypeID(ResType))
2130           .addUse(GR.getOrCreateConstInt(SPIRV::Scope::Subgroup, I, IntTy, TII))
2131           .addImm(SPIRV::GroupOperation::Reduce)
2132           .addUse(BallotReg)
2133           .constrainAllUses(TII, TRI, RBI);
2134 
2135   return Result;
2136 }
2137 
2138 bool SPIRVInstructionSelector::selectWaveReduceMax(Register ResVReg,
2139                                                    const SPIRVType *ResType,
2140                                                    MachineInstr &I,
2141                                                    bool IsUnsigned) const {
2142   assert(I.getNumOperands() == 3);
2143   assert(I.getOperand(2).isReg());
2144   MachineBasicBlock &BB = *I.getParent();
2145   Register InputRegister = I.getOperand(2).getReg();
2146   SPIRVType *InputType = GR.getSPIRVTypeForVReg(InputRegister);
2147 
2148   if (!InputType)
2149     report_fatal_error("Input Type could not be determined.");
2150 
2151   SPIRVType *IntTy = GR.getOrCreateSPIRVIntegerType(32, I, TII);
2152   // Retreive the operation to use based on input type
2153   bool IsFloatTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeFloat);
2154   auto IntegerOpcodeType =
2155       IsUnsigned ? SPIRV::OpGroupNonUniformUMax : SPIRV::OpGroupNonUniformSMax;
2156   auto Opcode = IsFloatTy ? SPIRV::OpGroupNonUniformFMax : IntegerOpcodeType;
2157   return BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2158       .addDef(ResVReg)
2159       .addUse(GR.getSPIRVTypeID(ResType))
2160       .addUse(GR.getOrCreateConstInt(SPIRV::Scope::Subgroup, I, IntTy, TII))
2161       .addImm(SPIRV::GroupOperation::Reduce)
2162       .addUse(I.getOperand(2).getReg())
2163       .constrainAllUses(TII, TRI, RBI);
2164 }
2165 
2166 bool SPIRVInstructionSelector::selectWaveReduceSum(Register ResVReg,
2167                                                    const SPIRVType *ResType,
2168                                                    MachineInstr &I) const {
2169   assert(I.getNumOperands() == 3);
2170   assert(I.getOperand(2).isReg());
2171   MachineBasicBlock &BB = *I.getParent();
2172   Register InputRegister = I.getOperand(2).getReg();
2173   SPIRVType *InputType = GR.getSPIRVTypeForVReg(InputRegister);
2174 
2175   if (!InputType)
2176     report_fatal_error("Input Type could not be determined.");
2177 
2178   SPIRVType *IntTy = GR.getOrCreateSPIRVIntegerType(32, I, TII);
2179   // Retreive the operation to use based on input type
2180   bool IsFloatTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeFloat);
2181   auto Opcode =
2182       IsFloatTy ? SPIRV::OpGroupNonUniformFAdd : SPIRV::OpGroupNonUniformIAdd;
2183   return BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2184       .addDef(ResVReg)
2185       .addUse(GR.getSPIRVTypeID(ResType))
2186       .addUse(GR.getOrCreateConstInt(SPIRV::Scope::Subgroup, I, IntTy, TII))
2187       .addImm(SPIRV::GroupOperation::Reduce)
2188       .addUse(I.getOperand(2).getReg());
2189 }
2190 
2191 bool SPIRVInstructionSelector::selectBitreverse(Register ResVReg,
2192                                                 const SPIRVType *ResType,
2193                                                 MachineInstr &I) const {
2194   MachineBasicBlock &BB = *I.getParent();
2195   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpBitReverse))
2196       .addDef(ResVReg)
2197       .addUse(GR.getSPIRVTypeID(ResType))
2198       .addUse(I.getOperand(1).getReg())
2199       .constrainAllUses(TII, TRI, RBI);
2200 }
2201 
2202 bool SPIRVInstructionSelector::selectFreeze(Register ResVReg,
2203                                             const SPIRVType *ResType,
2204                                             MachineInstr &I) const {
2205   // There is no way to implement `freeze` correctly without support on SPIR-V
2206   // standard side, but we may at least address a simple (static) case when
2207   // undef/poison value presence is obvious. The main benefit of even
2208   // incomplete `freeze` support is preventing of translation from crashing due
2209   // to lack of support on legalization and instruction selection steps.
2210   if (!I.getOperand(0).isReg() || !I.getOperand(1).isReg())
2211     return false;
2212   Register OpReg = I.getOperand(1).getReg();
2213   if (MachineInstr *Def = MRI->getVRegDef(OpReg)) {
2214     Register Reg;
2215     switch (Def->getOpcode()) {
2216     case SPIRV::ASSIGN_TYPE:
2217       if (MachineInstr *AssignToDef =
2218               MRI->getVRegDef(Def->getOperand(1).getReg())) {
2219         if (AssignToDef->getOpcode() == TargetOpcode::G_IMPLICIT_DEF)
2220           Reg = Def->getOperand(2).getReg();
2221       }
2222       break;
2223     case SPIRV::OpUndef:
2224       Reg = Def->getOperand(1).getReg();
2225       break;
2226     }
2227     unsigned DestOpCode;
2228     if (Reg.isValid()) {
2229       DestOpCode = SPIRV::OpConstantNull;
2230     } else {
2231       DestOpCode = TargetOpcode::COPY;
2232       Reg = OpReg;
2233     }
2234     return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(DestOpCode))
2235         .addDef(I.getOperand(0).getReg())
2236         .addUse(Reg)
2237         .constrainAllUses(TII, TRI, RBI);
2238   }
2239   return false;
2240 }
2241 
2242 static unsigned getArrayComponentCount(MachineRegisterInfo *MRI,
2243                                        const SPIRVType *ResType) {
2244   Register OpReg = ResType->getOperand(2).getReg();
2245   SPIRVType *OpDef = MRI->getVRegDef(OpReg);
2246   if (!OpDef)
2247     return 0;
2248   if (OpDef->getOpcode() == SPIRV::ASSIGN_TYPE &&
2249       OpDef->getOperand(1).isReg()) {
2250     if (SPIRVType *RefDef = MRI->getVRegDef(OpDef->getOperand(1).getReg()))
2251       OpDef = RefDef;
2252   }
2253   unsigned N = OpDef->getOpcode() == TargetOpcode::G_CONSTANT
2254                    ? OpDef->getOperand(1).getCImm()->getValue().getZExtValue()
2255                    : 0;
2256   return N;
2257 }
2258 
2259 // Return true if the type represents a constant register
2260 static bool isConstReg(MachineRegisterInfo *MRI, SPIRVType *OpDef,
2261                        SmallPtrSet<SPIRVType *, 4> &Visited) {
2262   if (OpDef->getOpcode() == SPIRV::ASSIGN_TYPE &&
2263       OpDef->getOperand(1).isReg()) {
2264     if (SPIRVType *RefDef = MRI->getVRegDef(OpDef->getOperand(1).getReg()))
2265       OpDef = RefDef;
2266   }
2267 
2268   if (Visited.contains(OpDef))
2269     return true;
2270   Visited.insert(OpDef);
2271 
2272   unsigned Opcode = OpDef->getOpcode();
2273   switch (Opcode) {
2274   case TargetOpcode::G_CONSTANT:
2275   case TargetOpcode::G_FCONSTANT:
2276     return true;
2277   case TargetOpcode::G_INTRINSIC:
2278   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
2279   case TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS:
2280     return cast<GIntrinsic>(*OpDef).getIntrinsicID() ==
2281            Intrinsic::spv_const_composite;
2282   case TargetOpcode::G_BUILD_VECTOR:
2283   case TargetOpcode::G_SPLAT_VECTOR: {
2284     for (unsigned i = OpDef->getNumExplicitDefs(); i < OpDef->getNumOperands();
2285          i++) {
2286       SPIRVType *OpNestedDef =
2287           OpDef->getOperand(i).isReg()
2288               ? MRI->getVRegDef(OpDef->getOperand(i).getReg())
2289               : nullptr;
2290       if (OpNestedDef && !isConstReg(MRI, OpNestedDef, Visited))
2291         return false;
2292     }
2293     return true;
2294   }
2295   }
2296   return false;
2297 }
2298 
2299 // Return true if the virtual register represents a constant
2300 static bool isConstReg(MachineRegisterInfo *MRI, Register OpReg) {
2301   SmallPtrSet<SPIRVType *, 4> Visited;
2302   if (SPIRVType *OpDef = MRI->getVRegDef(OpReg))
2303     return isConstReg(MRI, OpDef, Visited);
2304   return false;
2305 }
2306 
2307 bool SPIRVInstructionSelector::selectBuildVector(Register ResVReg,
2308                                                  const SPIRVType *ResType,
2309                                                  MachineInstr &I) const {
2310   unsigned N = 0;
2311   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2312     N = GR.getScalarOrVectorComponentCount(ResType);
2313   else if (ResType->getOpcode() == SPIRV::OpTypeArray)
2314     N = getArrayComponentCount(MRI, ResType);
2315   else
2316     report_fatal_error("Cannot select G_BUILD_VECTOR with a non-vector result");
2317   if (I.getNumExplicitOperands() - I.getNumExplicitDefs() != N)
2318     report_fatal_error("G_BUILD_VECTOR and the result type are inconsistent");
2319 
2320   // check if we may construct a constant vector
2321   bool IsConst = true;
2322   for (unsigned i = I.getNumExplicitDefs();
2323        i < I.getNumExplicitOperands() && IsConst; ++i)
2324     if (!isConstReg(MRI, I.getOperand(i).getReg()))
2325       IsConst = false;
2326 
2327   if (!IsConst && N < 2)
2328     report_fatal_error(
2329         "There must be at least two constituent operands in a vector");
2330 
2331   MRI->setRegClass(ResVReg, GR.getRegClass(ResType));
2332   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
2333                      TII.get(IsConst ? SPIRV::OpConstantComposite
2334                                      : SPIRV::OpCompositeConstruct))
2335                  .addDef(ResVReg)
2336                  .addUse(GR.getSPIRVTypeID(ResType));
2337   for (unsigned i = I.getNumExplicitDefs(); i < I.getNumExplicitOperands(); ++i)
2338     MIB.addUse(I.getOperand(i).getReg());
2339   return MIB.constrainAllUses(TII, TRI, RBI);
2340 }
2341 
2342 bool SPIRVInstructionSelector::selectSplatVector(Register ResVReg,
2343                                                  const SPIRVType *ResType,
2344                                                  MachineInstr &I) const {
2345   unsigned N = 0;
2346   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2347     N = GR.getScalarOrVectorComponentCount(ResType);
2348   else if (ResType->getOpcode() == SPIRV::OpTypeArray)
2349     N = getArrayComponentCount(MRI, ResType);
2350   else
2351     report_fatal_error("Cannot select G_SPLAT_VECTOR with a non-vector result");
2352 
2353   unsigned OpIdx = I.getNumExplicitDefs();
2354   if (!I.getOperand(OpIdx).isReg())
2355     report_fatal_error("Unexpected argument in G_SPLAT_VECTOR");
2356 
2357   // check if we may construct a constant vector
2358   Register OpReg = I.getOperand(OpIdx).getReg();
2359   bool IsConst = isConstReg(MRI, OpReg);
2360 
2361   if (!IsConst && N < 2)
2362     report_fatal_error(
2363         "There must be at least two constituent operands in a vector");
2364 
2365   MRI->setRegClass(ResVReg, GR.getRegClass(ResType));
2366   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
2367                      TII.get(IsConst ? SPIRV::OpConstantComposite
2368                                      : SPIRV::OpCompositeConstruct))
2369                  .addDef(ResVReg)
2370                  .addUse(GR.getSPIRVTypeID(ResType));
2371   for (unsigned i = 0; i < N; ++i)
2372     MIB.addUse(OpReg);
2373   return MIB.constrainAllUses(TII, TRI, RBI);
2374 }
2375 
2376 bool SPIRVInstructionSelector::selectDiscard(Register ResVReg,
2377                                              const SPIRVType *ResType,
2378                                              MachineInstr &I) const {
2379 
2380   unsigned Opcode;
2381 
2382   if (STI.canUseExtension(
2383           SPIRV::Extension::SPV_EXT_demote_to_helper_invocation) ||
2384       STI.isAtLeastSPIRVVer(llvm::VersionTuple(1, 6))) {
2385     Opcode = SPIRV::OpDemoteToHelperInvocation;
2386   } else {
2387     Opcode = SPIRV::OpKill;
2388     // OpKill must be the last operation of any basic block.
2389     if (MachineInstr *NextI = I.getNextNode()) {
2390       GR.invalidateMachineInstr(NextI);
2391       NextI->removeFromParent();
2392     }
2393   }
2394 
2395   MachineBasicBlock &BB = *I.getParent();
2396   return BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2397       .constrainAllUses(TII, TRI, RBI);
2398 }
2399 
2400 bool SPIRVInstructionSelector::selectCmp(Register ResVReg,
2401                                          const SPIRVType *ResType,
2402                                          unsigned CmpOpc,
2403                                          MachineInstr &I) const {
2404   Register Cmp0 = I.getOperand(2).getReg();
2405   Register Cmp1 = I.getOperand(3).getReg();
2406   assert(GR.getSPIRVTypeForVReg(Cmp0)->getOpcode() ==
2407              GR.getSPIRVTypeForVReg(Cmp1)->getOpcode() &&
2408          "CMP operands should have the same type");
2409   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(CmpOpc))
2410       .addDef(ResVReg)
2411       .addUse(GR.getSPIRVTypeID(ResType))
2412       .addUse(Cmp0)
2413       .addUse(Cmp1)
2414       .constrainAllUses(TII, TRI, RBI);
2415 }
2416 
2417 bool SPIRVInstructionSelector::selectICmp(Register ResVReg,
2418                                           const SPIRVType *ResType,
2419                                           MachineInstr &I) const {
2420   auto Pred = I.getOperand(1).getPredicate();
2421   unsigned CmpOpc;
2422 
2423   Register CmpOperand = I.getOperand(2).getReg();
2424   if (GR.isScalarOfType(CmpOperand, SPIRV::OpTypePointer))
2425     CmpOpc = getPtrCmpOpcode(Pred);
2426   else if (GR.isScalarOrVectorOfType(CmpOperand, SPIRV::OpTypeBool))
2427     CmpOpc = getBoolCmpOpcode(Pred);
2428   else
2429     CmpOpc = getICmpOpcode(Pred);
2430   return selectCmp(ResVReg, ResType, CmpOpc, I);
2431 }
2432 
2433 void SPIRVInstructionSelector::renderFImm64(MachineInstrBuilder &MIB,
2434                                             const MachineInstr &I,
2435                                             int OpIdx) const {
2436   assert(I.getOpcode() == TargetOpcode::G_FCONSTANT && OpIdx == -1 &&
2437          "Expected G_FCONSTANT");
2438   const ConstantFP *FPImm = I.getOperand(1).getFPImm();
2439   addNumImm(FPImm->getValueAPF().bitcastToAPInt(), MIB);
2440 }
2441 
2442 void SPIRVInstructionSelector::renderImm32(MachineInstrBuilder &MIB,
2443                                            const MachineInstr &I,
2444                                            int OpIdx) const {
2445   assert(I.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
2446          "Expected G_CONSTANT");
2447   addNumImm(I.getOperand(1).getCImm()->getValue(), MIB);
2448 }
2449 
2450 std::pair<Register, bool>
2451 SPIRVInstructionSelector::buildI32Constant(uint32_t Val, MachineInstr &I,
2452                                            const SPIRVType *ResType) const {
2453   Type *LLVMTy = IntegerType::get(GR.CurMF->getFunction().getContext(), 32);
2454   const SPIRVType *SpvI32Ty =
2455       ResType ? ResType : GR.getOrCreateSPIRVIntegerType(32, I, TII);
2456   // Find a constant in DT or build a new one.
2457   auto ConstInt = ConstantInt::get(LLVMTy, Val);
2458   Register NewReg = GR.find(ConstInt, GR.CurMF);
2459   bool Result = true;
2460   if (!NewReg.isValid()) {
2461     NewReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
2462     GR.add(ConstInt, GR.CurMF, NewReg);
2463     MachineInstr *MI;
2464     MachineBasicBlock &BB = *I.getParent();
2465     if (Val == 0) {
2466       MI = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
2467                .addDef(NewReg)
2468                .addUse(GR.getSPIRVTypeID(SpvI32Ty));
2469     } else {
2470       MI = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantI))
2471                .addDef(NewReg)
2472                .addUse(GR.getSPIRVTypeID(SpvI32Ty))
2473                .addImm(APInt(32, Val).getZExtValue());
2474     }
2475     Result &= constrainSelectedInstRegOperands(*MI, TII, TRI, RBI);
2476   }
2477   return {NewReg, Result};
2478 }
2479 
2480 bool SPIRVInstructionSelector::selectFCmp(Register ResVReg,
2481                                           const SPIRVType *ResType,
2482                                           MachineInstr &I) const {
2483   unsigned CmpOp = getFCmpOpcode(I.getOperand(1).getPredicate());
2484   return selectCmp(ResVReg, ResType, CmpOp, I);
2485 }
2486 
2487 Register SPIRVInstructionSelector::buildZerosVal(const SPIRVType *ResType,
2488                                                  MachineInstr &I) const {
2489   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
2490   bool ZeroAsNull = STI.isOpenCLEnv();
2491   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2492     return GR.getOrCreateConstVector(0UL, I, ResType, TII, ZeroAsNull);
2493   return GR.getOrCreateConstInt(0, I, ResType, TII, ZeroAsNull);
2494 }
2495 
2496 Register SPIRVInstructionSelector::buildZerosValF(const SPIRVType *ResType,
2497                                                   MachineInstr &I) const {
2498   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
2499   bool ZeroAsNull = STI.isOpenCLEnv();
2500   APFloat VZero = getZeroFP(GR.getTypeForSPIRVType(ResType));
2501   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2502     return GR.getOrCreateConstVector(VZero, I, ResType, TII, ZeroAsNull);
2503   return GR.getOrCreateConstFP(VZero, I, ResType, TII, ZeroAsNull);
2504 }
2505 
2506 Register SPIRVInstructionSelector::buildOnesValF(const SPIRVType *ResType,
2507                                                  MachineInstr &I) const {
2508   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
2509   bool ZeroAsNull = STI.isOpenCLEnv();
2510   APFloat VOne = getOneFP(GR.getTypeForSPIRVType(ResType));
2511   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2512     return GR.getOrCreateConstVector(VOne, I, ResType, TII, ZeroAsNull);
2513   return GR.getOrCreateConstFP(VOne, I, ResType, TII, ZeroAsNull);
2514 }
2515 
2516 Register SPIRVInstructionSelector::buildOnesVal(bool AllOnes,
2517                                                 const SPIRVType *ResType,
2518                                                 MachineInstr &I) const {
2519   unsigned BitWidth = GR.getScalarOrVectorBitWidth(ResType);
2520   APInt One =
2521       AllOnes ? APInt::getAllOnes(BitWidth) : APInt::getOneBitSet(BitWidth, 0);
2522   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2523     return GR.getOrCreateConstVector(One.getZExtValue(), I, ResType, TII);
2524   return GR.getOrCreateConstInt(One.getZExtValue(), I, ResType, TII);
2525 }
2526 
2527 bool SPIRVInstructionSelector::selectSelect(Register ResVReg,
2528                                             const SPIRVType *ResType,
2529                                             MachineInstr &I,
2530                                             bool IsSigned) const {
2531   // To extend a bool, we need to use OpSelect between constants.
2532   Register ZeroReg = buildZerosVal(ResType, I);
2533   Register OneReg = buildOnesVal(IsSigned, ResType, I);
2534   bool IsScalarBool =
2535       GR.isScalarOfType(I.getOperand(1).getReg(), SPIRV::OpTypeBool);
2536   unsigned Opcode =
2537       IsScalarBool ? SPIRV::OpSelectSISCond : SPIRV::OpSelectVIVCond;
2538   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
2539       .addDef(ResVReg)
2540       .addUse(GR.getSPIRVTypeID(ResType))
2541       .addUse(I.getOperand(1).getReg())
2542       .addUse(OneReg)
2543       .addUse(ZeroReg)
2544       .constrainAllUses(TII, TRI, RBI);
2545 }
2546 
2547 bool SPIRVInstructionSelector::selectIToF(Register ResVReg,
2548                                           const SPIRVType *ResType,
2549                                           MachineInstr &I, bool IsSigned,
2550                                           unsigned Opcode) const {
2551   Register SrcReg = I.getOperand(1).getReg();
2552   // We can convert bool value directly to float type without OpConvert*ToF,
2553   // however the translator generates OpSelect+OpConvert*ToF, so we do the same.
2554   if (GR.isScalarOrVectorOfType(I.getOperand(1).getReg(), SPIRV::OpTypeBool)) {
2555     unsigned BitWidth = GR.getScalarOrVectorBitWidth(ResType);
2556     SPIRVType *TmpType = GR.getOrCreateSPIRVIntegerType(BitWidth, I, TII);
2557     if (ResType->getOpcode() == SPIRV::OpTypeVector) {
2558       const unsigned NumElts = ResType->getOperand(2).getImm();
2559       TmpType = GR.getOrCreateSPIRVVectorType(TmpType, NumElts, I, TII);
2560     }
2561     SrcReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2562     selectSelect(SrcReg, TmpType, I, false);
2563   }
2564   return selectOpWithSrcs(ResVReg, ResType, I, {SrcReg}, Opcode);
2565 }
2566 
2567 bool SPIRVInstructionSelector::selectExt(Register ResVReg,
2568                                          const SPIRVType *ResType,
2569                                          MachineInstr &I, bool IsSigned) const {
2570   Register SrcReg = I.getOperand(1).getReg();
2571   if (GR.isScalarOrVectorOfType(SrcReg, SPIRV::OpTypeBool))
2572     return selectSelect(ResVReg, ResType, I, IsSigned);
2573 
2574   SPIRVType *SrcType = GR.getSPIRVTypeForVReg(SrcReg);
2575   if (SrcType == ResType)
2576     return BuildCOPY(ResVReg, SrcReg, I);
2577 
2578   unsigned Opcode = IsSigned ? SPIRV::OpSConvert : SPIRV::OpUConvert;
2579   return selectUnOp(ResVReg, ResType, I, Opcode);
2580 }
2581 
2582 bool SPIRVInstructionSelector::selectSUCmp(Register ResVReg,
2583                                            const SPIRVType *ResType,
2584                                            MachineInstr &I,
2585                                            bool IsSigned) const {
2586   MachineIRBuilder MIRBuilder(I);
2587   MachineRegisterInfo *MRI = MIRBuilder.getMRI();
2588   MachineBasicBlock &BB = *I.getParent();
2589   // Ensure we have bool.
2590   SPIRVType *BoolType = GR.getOrCreateSPIRVBoolType(I, TII);
2591   unsigned N = GR.getScalarOrVectorComponentCount(ResType);
2592   if (N > 1)
2593     BoolType = GR.getOrCreateSPIRVVectorType(BoolType, N, I, TII);
2594   Register BoolTypeReg = GR.getSPIRVTypeID(BoolType);
2595   // Build less-than-equal and less-than.
2596   // TODO: replace with one-liner createVirtualRegister() from
2597   // llvm/lib/Target/SPIRV/SPIRVUtils.cpp when PR #116609 is merged.
2598   Register IsLessEqReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
2599   MRI->setType(IsLessEqReg, LLT::scalar(64));
2600   GR.assignSPIRVTypeToVReg(ResType, IsLessEqReg, MIRBuilder.getMF());
2601   bool Result = BuildMI(BB, I, I.getDebugLoc(),
2602                         TII.get(IsSigned ? SPIRV::OpSLessThanEqual
2603                                          : SPIRV::OpULessThanEqual))
2604                     .addDef(IsLessEqReg)
2605                     .addUse(BoolTypeReg)
2606                     .addUse(I.getOperand(1).getReg())
2607                     .addUse(I.getOperand(2).getReg())
2608                     .constrainAllUses(TII, TRI, RBI);
2609   Register IsLessReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
2610   MRI->setType(IsLessReg, LLT::scalar(64));
2611   GR.assignSPIRVTypeToVReg(ResType, IsLessReg, MIRBuilder.getMF());
2612   Result &= BuildMI(BB, I, I.getDebugLoc(),
2613                     TII.get(IsSigned ? SPIRV::OpSLessThan : SPIRV::OpULessThan))
2614                 .addDef(IsLessReg)
2615                 .addUse(BoolTypeReg)
2616                 .addUse(I.getOperand(1).getReg())
2617                 .addUse(I.getOperand(2).getReg())
2618                 .constrainAllUses(TII, TRI, RBI);
2619   // Build selects.
2620   Register ResTypeReg = GR.getSPIRVTypeID(ResType);
2621   Register NegOneOrZeroReg =
2622       MRI->createVirtualRegister(GR.getRegClass(ResType));
2623   MRI->setType(NegOneOrZeroReg, LLT::scalar(64));
2624   GR.assignSPIRVTypeToVReg(ResType, NegOneOrZeroReg, MIRBuilder.getMF());
2625   unsigned SelectOpcode =
2626       N > 1 ? SPIRV::OpSelectVIVCond : SPIRV::OpSelectSISCond;
2627   Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SelectOpcode))
2628                 .addDef(NegOneOrZeroReg)
2629                 .addUse(ResTypeReg)
2630                 .addUse(IsLessReg)
2631                 .addUse(buildOnesVal(true, ResType, I)) // -1
2632                 .addUse(buildZerosVal(ResType, I))
2633                 .constrainAllUses(TII, TRI, RBI);
2634   return Result & BuildMI(BB, I, I.getDebugLoc(), TII.get(SelectOpcode))
2635                       .addDef(ResVReg)
2636                       .addUse(ResTypeReg)
2637                       .addUse(IsLessEqReg)
2638                       .addUse(NegOneOrZeroReg) // -1 or 0
2639                       .addUse(buildOnesVal(false, ResType, I))
2640                       .constrainAllUses(TII, TRI, RBI);
2641 }
2642 
2643 bool SPIRVInstructionSelector::selectIntToBool(Register IntReg,
2644                                                Register ResVReg,
2645                                                MachineInstr &I,
2646                                                const SPIRVType *IntTy,
2647                                                const SPIRVType *BoolTy) const {
2648   // To truncate to a bool, we use OpBitwiseAnd 1 and OpINotEqual to zero.
2649   Register BitIntReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2650   bool IsVectorTy = IntTy->getOpcode() == SPIRV::OpTypeVector;
2651   unsigned Opcode = IsVectorTy ? SPIRV::OpBitwiseAndV : SPIRV::OpBitwiseAndS;
2652   Register Zero = buildZerosVal(IntTy, I);
2653   Register One = buildOnesVal(false, IntTy, I);
2654   MachineBasicBlock &BB = *I.getParent();
2655   bool Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2656                     .addDef(BitIntReg)
2657                     .addUse(GR.getSPIRVTypeID(IntTy))
2658                     .addUse(IntReg)
2659                     .addUse(One)
2660                     .constrainAllUses(TII, TRI, RBI);
2661   return Result && BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpINotEqual))
2662                        .addDef(ResVReg)
2663                        .addUse(GR.getSPIRVTypeID(BoolTy))
2664                        .addUse(BitIntReg)
2665                        .addUse(Zero)
2666                        .constrainAllUses(TII, TRI, RBI);
2667 }
2668 
2669 bool SPIRVInstructionSelector::selectTrunc(Register ResVReg,
2670                                            const SPIRVType *ResType,
2671                                            MachineInstr &I) const {
2672   Register IntReg = I.getOperand(1).getReg();
2673   const SPIRVType *ArgType = GR.getSPIRVTypeForVReg(IntReg);
2674   if (GR.isScalarOrVectorOfType(ResVReg, SPIRV::OpTypeBool))
2675     return selectIntToBool(IntReg, ResVReg, I, ArgType, ResType);
2676   if (ArgType == ResType)
2677     return BuildCOPY(ResVReg, IntReg, I);
2678   bool IsSigned = GR.isScalarOrVectorSigned(ResType);
2679   unsigned Opcode = IsSigned ? SPIRV::OpSConvert : SPIRV::OpUConvert;
2680   return selectUnOp(ResVReg, ResType, I, Opcode);
2681 }
2682 
2683 bool SPIRVInstructionSelector::selectConst(Register ResVReg,
2684                                            const SPIRVType *ResType,
2685                                            const APInt &Imm,
2686                                            MachineInstr &I) const {
2687   unsigned TyOpcode = ResType->getOpcode();
2688   assert(TyOpcode != SPIRV::OpTypePointer || Imm.isZero());
2689   MachineBasicBlock &BB = *I.getParent();
2690   if ((TyOpcode == SPIRV::OpTypePointer || TyOpcode == SPIRV::OpTypeEvent) &&
2691       Imm.isZero())
2692     return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
2693         .addDef(ResVReg)
2694         .addUse(GR.getSPIRVTypeID(ResType))
2695         .constrainAllUses(TII, TRI, RBI);
2696   if (TyOpcode == SPIRV::OpTypeInt) {
2697     assert(Imm.getBitWidth() <= 64 && "Unsupported integer width!");
2698     Register Reg = GR.getOrCreateConstInt(Imm.getZExtValue(), I, ResType, TII);
2699     return Reg == ResVReg ? true : BuildCOPY(ResVReg, Reg, I);
2700   }
2701   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantI))
2702                  .addDef(ResVReg)
2703                  .addUse(GR.getSPIRVTypeID(ResType));
2704   // <=32-bit integers should be caught by the sdag pattern.
2705   assert(Imm.getBitWidth() > 32);
2706   addNumImm(Imm, MIB);
2707   return MIB.constrainAllUses(TII, TRI, RBI);
2708 }
2709 
2710 bool SPIRVInstructionSelector::selectOpUndef(Register ResVReg,
2711                                              const SPIRVType *ResType,
2712                                              MachineInstr &I) const {
2713   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpUndef))
2714       .addDef(ResVReg)
2715       .addUse(GR.getSPIRVTypeID(ResType))
2716       .constrainAllUses(TII, TRI, RBI);
2717 }
2718 
2719 static bool isImm(const MachineOperand &MO, MachineRegisterInfo *MRI) {
2720   assert(MO.isReg());
2721   const SPIRVType *TypeInst = MRI->getVRegDef(MO.getReg());
2722   if (TypeInst->getOpcode() == SPIRV::ASSIGN_TYPE) {
2723     assert(TypeInst->getOperand(1).isReg());
2724     MachineInstr *ImmInst = MRI->getVRegDef(TypeInst->getOperand(1).getReg());
2725     return ImmInst->getOpcode() == TargetOpcode::G_CONSTANT;
2726   }
2727   return TypeInst->getOpcode() == SPIRV::OpConstantI;
2728 }
2729 
2730 static int64_t foldImm(const MachineOperand &MO, MachineRegisterInfo *MRI) {
2731   const SPIRVType *TypeInst = MRI->getVRegDef(MO.getReg());
2732   if (TypeInst->getOpcode() == SPIRV::OpConstantI)
2733     return TypeInst->getOperand(2).getImm();
2734   MachineInstr *ImmInst = MRI->getVRegDef(TypeInst->getOperand(1).getReg());
2735   assert(ImmInst->getOpcode() == TargetOpcode::G_CONSTANT);
2736   return ImmInst->getOperand(1).getCImm()->getZExtValue();
2737 }
2738 
2739 bool SPIRVInstructionSelector::selectInsertVal(Register ResVReg,
2740                                                const SPIRVType *ResType,
2741                                                MachineInstr &I) const {
2742   MachineBasicBlock &BB = *I.getParent();
2743   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeInsert))
2744                  .addDef(ResVReg)
2745                  .addUse(GR.getSPIRVTypeID(ResType))
2746                  // object to insert
2747                  .addUse(I.getOperand(3).getReg())
2748                  // composite to insert into
2749                  .addUse(I.getOperand(2).getReg());
2750   for (unsigned i = 4; i < I.getNumOperands(); i++)
2751     MIB.addImm(foldImm(I.getOperand(i), MRI));
2752   return MIB.constrainAllUses(TII, TRI, RBI);
2753 }
2754 
2755 bool SPIRVInstructionSelector::selectExtractVal(Register ResVReg,
2756                                                 const SPIRVType *ResType,
2757                                                 MachineInstr &I) const {
2758   MachineBasicBlock &BB = *I.getParent();
2759   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
2760                  .addDef(ResVReg)
2761                  .addUse(GR.getSPIRVTypeID(ResType))
2762                  .addUse(I.getOperand(2).getReg());
2763   for (unsigned i = 3; i < I.getNumOperands(); i++)
2764     MIB.addImm(foldImm(I.getOperand(i), MRI));
2765   return MIB.constrainAllUses(TII, TRI, RBI);
2766 }
2767 
2768 bool SPIRVInstructionSelector::selectInsertElt(Register ResVReg,
2769                                                const SPIRVType *ResType,
2770                                                MachineInstr &I) const {
2771   if (isImm(I.getOperand(4), MRI))
2772     return selectInsertVal(ResVReg, ResType, I);
2773   MachineBasicBlock &BB = *I.getParent();
2774   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorInsertDynamic))
2775       .addDef(ResVReg)
2776       .addUse(GR.getSPIRVTypeID(ResType))
2777       .addUse(I.getOperand(2).getReg())
2778       .addUse(I.getOperand(3).getReg())
2779       .addUse(I.getOperand(4).getReg())
2780       .constrainAllUses(TII, TRI, RBI);
2781 }
2782 
2783 bool SPIRVInstructionSelector::selectExtractElt(Register ResVReg,
2784                                                 const SPIRVType *ResType,
2785                                                 MachineInstr &I) const {
2786   if (isImm(I.getOperand(3), MRI))
2787     return selectExtractVal(ResVReg, ResType, I);
2788   MachineBasicBlock &BB = *I.getParent();
2789   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorExtractDynamic))
2790       .addDef(ResVReg)
2791       .addUse(GR.getSPIRVTypeID(ResType))
2792       .addUse(I.getOperand(2).getReg())
2793       .addUse(I.getOperand(3).getReg())
2794       .constrainAllUses(TII, TRI, RBI);
2795 }
2796 
2797 bool SPIRVInstructionSelector::selectGEP(Register ResVReg,
2798                                          const SPIRVType *ResType,
2799                                          MachineInstr &I) const {
2800   const bool IsGEPInBounds = I.getOperand(2).getImm();
2801 
2802   // OpAccessChain could be used for OpenCL, but the SPIRV-LLVM Translator only
2803   // relies on PtrAccessChain, so we'll try not to deviate. For Vulkan however,
2804   // we have to use Op[InBounds]AccessChain.
2805   const unsigned Opcode = STI.isVulkanEnv()
2806                               ? (IsGEPInBounds ? SPIRV::OpInBoundsAccessChain
2807                                                : SPIRV::OpAccessChain)
2808                               : (IsGEPInBounds ? SPIRV::OpInBoundsPtrAccessChain
2809                                                : SPIRV::OpPtrAccessChain);
2810 
2811   auto Res = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
2812                  .addDef(ResVReg)
2813                  .addUse(GR.getSPIRVTypeID(ResType))
2814                  // Object to get a pointer to.
2815                  .addUse(I.getOperand(3).getReg());
2816   // Adding indices.
2817   const unsigned StartingIndex =
2818       (Opcode == SPIRV::OpAccessChain || Opcode == SPIRV::OpInBoundsAccessChain)
2819           ? 5
2820           : 4;
2821   for (unsigned i = StartingIndex; i < I.getNumExplicitOperands(); ++i)
2822     Res.addUse(I.getOperand(i).getReg());
2823   return Res.constrainAllUses(TII, TRI, RBI);
2824 }
2825 
2826 // Maybe wrap a value into OpSpecConstantOp
2827 bool SPIRVInstructionSelector::wrapIntoSpecConstantOp(
2828     MachineInstr &I, SmallVector<Register> &CompositeArgs) const {
2829   bool Result = true;
2830   unsigned Lim = I.getNumExplicitOperands();
2831   for (unsigned i = I.getNumExplicitDefs() + 1; i < Lim; ++i) {
2832     Register OpReg = I.getOperand(i).getReg();
2833     SPIRVType *OpDefine = MRI->getVRegDef(OpReg);
2834     SPIRVType *OpType = GR.getSPIRVTypeForVReg(OpReg);
2835     SmallPtrSet<SPIRVType *, 4> Visited;
2836     if (!OpDefine || !OpType || isConstReg(MRI, OpDefine, Visited) ||
2837         OpDefine->getOpcode() == TargetOpcode::G_ADDRSPACE_CAST ||
2838         GR.isAggregateType(OpType)) {
2839       // The case of G_ADDRSPACE_CAST inside spv_const_composite() is processed
2840       // by selectAddrSpaceCast()
2841       CompositeArgs.push_back(OpReg);
2842       continue;
2843     }
2844     MachineFunction *MF = I.getMF();
2845     Register WrapReg = GR.find(OpDefine, MF);
2846     if (WrapReg.isValid()) {
2847       CompositeArgs.push_back(WrapReg);
2848       continue;
2849     }
2850     // Create a new register for the wrapper
2851     WrapReg = MRI->createVirtualRegister(GR.getRegClass(OpType));
2852     GR.add(OpDefine, MF, WrapReg);
2853     CompositeArgs.push_back(WrapReg);
2854     // Decorate the wrapper register and generate a new instruction
2855     MRI->setType(WrapReg, LLT::pointer(0, 64));
2856     GR.assignSPIRVTypeToVReg(OpType, WrapReg, *MF);
2857     MachineBasicBlock &BB = *I.getParent();
2858     Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
2859                  .addDef(WrapReg)
2860                  .addUse(GR.getSPIRVTypeID(OpType))
2861                  .addImm(static_cast<uint32_t>(SPIRV::Opcode::Bitcast))
2862                  .addUse(OpReg)
2863                  .constrainAllUses(TII, TRI, RBI);
2864     if (!Result)
2865       break;
2866   }
2867   return Result;
2868 }
2869 
2870 bool SPIRVInstructionSelector::selectIntrinsic(Register ResVReg,
2871                                                const SPIRVType *ResType,
2872                                                MachineInstr &I) const {
2873   MachineBasicBlock &BB = *I.getParent();
2874   Intrinsic::ID IID = cast<GIntrinsic>(I).getIntrinsicID();
2875   switch (IID) {
2876   case Intrinsic::spv_load:
2877     return selectLoad(ResVReg, ResType, I);
2878   case Intrinsic::spv_store:
2879     return selectStore(I);
2880   case Intrinsic::spv_extractv:
2881     return selectExtractVal(ResVReg, ResType, I);
2882   case Intrinsic::spv_insertv:
2883     return selectInsertVal(ResVReg, ResType, I);
2884   case Intrinsic::spv_extractelt:
2885     return selectExtractElt(ResVReg, ResType, I);
2886   case Intrinsic::spv_insertelt:
2887     return selectInsertElt(ResVReg, ResType, I);
2888   case Intrinsic::spv_gep:
2889     return selectGEP(ResVReg, ResType, I);
2890   case Intrinsic::spv_unref_global:
2891   case Intrinsic::spv_init_global: {
2892     MachineInstr *MI = MRI->getVRegDef(I.getOperand(1).getReg());
2893     MachineInstr *Init = I.getNumExplicitOperands() > 2
2894                              ? MRI->getVRegDef(I.getOperand(2).getReg())
2895                              : nullptr;
2896     assert(MI);
2897     return selectGlobalValue(MI->getOperand(0).getReg(), *MI, Init);
2898   }
2899   case Intrinsic::spv_undef: {
2900     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpUndef))
2901                    .addDef(ResVReg)
2902                    .addUse(GR.getSPIRVTypeID(ResType));
2903     return MIB.constrainAllUses(TII, TRI, RBI);
2904   }
2905   case Intrinsic::spv_const_composite: {
2906     // If no values are attached, the composite is null constant.
2907     bool IsNull = I.getNumExplicitDefs() + 1 == I.getNumExplicitOperands();
2908     // Select a proper instruction.
2909     unsigned Opcode = SPIRV::OpConstantNull;
2910     SmallVector<Register> CompositeArgs;
2911     if (!IsNull) {
2912       Opcode = SPIRV::OpConstantComposite;
2913       if (!wrapIntoSpecConstantOp(I, CompositeArgs))
2914         return false;
2915     }
2916     MRI->setRegClass(ResVReg, GR.getRegClass(ResType));
2917     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2918                    .addDef(ResVReg)
2919                    .addUse(GR.getSPIRVTypeID(ResType));
2920     // skip type MD node we already used when generated assign.type for this
2921     if (!IsNull) {
2922       for (Register OpReg : CompositeArgs)
2923         MIB.addUse(OpReg);
2924     }
2925     return MIB.constrainAllUses(TII, TRI, RBI);
2926   }
2927   case Intrinsic::spv_assign_name: {
2928     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpName));
2929     MIB.addUse(I.getOperand(I.getNumExplicitDefs() + 1).getReg());
2930     for (unsigned i = I.getNumExplicitDefs() + 2;
2931          i < I.getNumExplicitOperands(); ++i) {
2932       MIB.addImm(I.getOperand(i).getImm());
2933     }
2934     return MIB.constrainAllUses(TII, TRI, RBI);
2935   }
2936   case Intrinsic::spv_switch: {
2937     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSwitch));
2938     for (unsigned i = 1; i < I.getNumExplicitOperands(); ++i) {
2939       if (I.getOperand(i).isReg())
2940         MIB.addReg(I.getOperand(i).getReg());
2941       else if (I.getOperand(i).isCImm())
2942         addNumImm(I.getOperand(i).getCImm()->getValue(), MIB);
2943       else if (I.getOperand(i).isMBB())
2944         MIB.addMBB(I.getOperand(i).getMBB());
2945       else
2946         llvm_unreachable("Unexpected OpSwitch operand");
2947     }
2948     return MIB.constrainAllUses(TII, TRI, RBI);
2949   }
2950   case Intrinsic::spv_loop_merge: {
2951     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpLoopMerge));
2952     for (unsigned i = 1; i < I.getNumExplicitOperands(); ++i) {
2953       assert(I.getOperand(i).isMBB());
2954       MIB.addMBB(I.getOperand(i).getMBB());
2955     }
2956     MIB.addImm(SPIRV::SelectionControl::None);
2957     return MIB.constrainAllUses(TII, TRI, RBI);
2958   }
2959   case Intrinsic::spv_selection_merge: {
2960     auto MIB =
2961         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSelectionMerge));
2962     assert(I.getOperand(1).isMBB() &&
2963            "operand 1 to spv_selection_merge must be a basic block");
2964     MIB.addMBB(I.getOperand(1).getMBB());
2965     MIB.addImm(getSelectionOperandForImm(I.getOperand(2).getImm()));
2966     return MIB.constrainAllUses(TII, TRI, RBI);
2967   }
2968   case Intrinsic::spv_cmpxchg:
2969     return selectAtomicCmpXchg(ResVReg, ResType, I);
2970   case Intrinsic::spv_unreachable:
2971     return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpUnreachable))
2972         .constrainAllUses(TII, TRI, RBI);
2973   case Intrinsic::spv_alloca:
2974     return selectFrameIndex(ResVReg, ResType, I);
2975   case Intrinsic::spv_alloca_array:
2976     return selectAllocaArray(ResVReg, ResType, I);
2977   case Intrinsic::spv_assume:
2978     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_expect_assume))
2979       return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpAssumeTrueKHR))
2980           .addUse(I.getOperand(1).getReg())
2981           .constrainAllUses(TII, TRI, RBI);
2982     break;
2983   case Intrinsic::spv_expect:
2984     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_expect_assume))
2985       return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExpectKHR))
2986           .addDef(ResVReg)
2987           .addUse(GR.getSPIRVTypeID(ResType))
2988           .addUse(I.getOperand(2).getReg())
2989           .addUse(I.getOperand(3).getReg())
2990           .constrainAllUses(TII, TRI, RBI);
2991     break;
2992   case Intrinsic::arithmetic_fence:
2993     if (STI.canUseExtension(SPIRV::Extension::SPV_EXT_arithmetic_fence))
2994       return BuildMI(BB, I, I.getDebugLoc(),
2995                      TII.get(SPIRV::OpArithmeticFenceEXT))
2996           .addDef(ResVReg)
2997           .addUse(GR.getSPIRVTypeID(ResType))
2998           .addUse(I.getOperand(2).getReg())
2999           .constrainAllUses(TII, TRI, RBI);
3000     else
3001       return BuildCOPY(ResVReg, I.getOperand(2).getReg(), I);
3002     break;
3003   case Intrinsic::spv_thread_id:
3004     // The HLSL SV_DispatchThreadID semantic is lowered to llvm.spv.thread.id
3005     // intrinsic in LLVM IR for SPIR-V backend.
3006     //
3007     // In SPIR-V backend, llvm.spv.thread.id is now correctly translated to a
3008     // `GlobalInvocationId` builtin variable
3009     return loadVec3BuiltinInputID(SPIRV::BuiltIn::GlobalInvocationId, ResVReg,
3010                                   ResType, I);
3011   case Intrinsic::spv_thread_id_in_group:
3012     // The HLSL SV_GroupThreadId semantic is lowered to
3013     // llvm.spv.thread.id.in.group intrinsic in LLVM IR for SPIR-V backend.
3014     //
3015     // In SPIR-V backend, llvm.spv.thread.id.in.group is now correctly
3016     // translated to a `LocalInvocationId` builtin variable
3017     return loadVec3BuiltinInputID(SPIRV::BuiltIn::LocalInvocationId, ResVReg,
3018                                   ResType, I);
3019   case Intrinsic::spv_group_id:
3020     // The HLSL SV_GroupId semantic is lowered to
3021     // llvm.spv.group.id intrinsic in LLVM IR for SPIR-V backend.
3022     //
3023     // In SPIR-V backend, llvm.spv.group.id is now translated to a `WorkgroupId`
3024     // builtin variable
3025     return loadVec3BuiltinInputID(SPIRV::BuiltIn::WorkgroupId, ResVReg, ResType,
3026                                   I);
3027   case Intrinsic::spv_fdot:
3028     return selectFloatDot(ResVReg, ResType, I);
3029   case Intrinsic::spv_udot:
3030   case Intrinsic::spv_sdot:
3031     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_integer_dot_product) ||
3032         STI.isAtLeastSPIRVVer(VersionTuple(1, 6)))
3033       return selectIntegerDot(ResVReg, ResType, I,
3034                               /*Signed=*/IID == Intrinsic::spv_sdot);
3035     return selectIntegerDotExpansion(ResVReg, ResType, I);
3036   case Intrinsic::spv_dot4add_i8packed:
3037     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_integer_dot_product) ||
3038         STI.isAtLeastSPIRVVer(VersionTuple(1, 6)))
3039       return selectDot4AddPacked<true>(ResVReg, ResType, I);
3040     return selectDot4AddPackedExpansion<true>(ResVReg, ResType, I);
3041   case Intrinsic::spv_dot4add_u8packed:
3042     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_integer_dot_product) ||
3043         STI.isAtLeastSPIRVVer(VersionTuple(1, 6)))
3044       return selectDot4AddPacked<false>(ResVReg, ResType, I);
3045     return selectDot4AddPackedExpansion<false>(ResVReg, ResType, I);
3046   case Intrinsic::spv_all:
3047     return selectAll(ResVReg, ResType, I);
3048   case Intrinsic::spv_any:
3049     return selectAny(ResVReg, ResType, I);
3050   case Intrinsic::spv_cross:
3051     return selectExtInst(ResVReg, ResType, I, CL::cross, GL::Cross);
3052   case Intrinsic::spv_distance:
3053     return selectExtInst(ResVReg, ResType, I, CL::distance, GL::Distance);
3054   case Intrinsic::spv_lerp:
3055     return selectExtInst(ResVReg, ResType, I, CL::mix, GL::FMix);
3056   case Intrinsic::spv_length:
3057     return selectExtInst(ResVReg, ResType, I, CL::length, GL::Length);
3058   case Intrinsic::spv_degrees:
3059     return selectExtInst(ResVReg, ResType, I, CL::degrees, GL::Degrees);
3060   case Intrinsic::spv_frac:
3061     return selectExtInst(ResVReg, ResType, I, CL::fract, GL::Fract);
3062   case Intrinsic::spv_normalize:
3063     return selectExtInst(ResVReg, ResType, I, CL::normalize, GL::Normalize);
3064   case Intrinsic::spv_rsqrt:
3065     return selectExtInst(ResVReg, ResType, I, CL::rsqrt, GL::InverseSqrt);
3066   case Intrinsic::spv_sign:
3067     return selectSign(ResVReg, ResType, I);
3068   case Intrinsic::spv_firstbituhigh: // There is no CL equivalent of FindUMsb
3069     return selectFirstBitHigh(ResVReg, ResType, I, /*IsSigned=*/false);
3070   case Intrinsic::spv_firstbitshigh: // There is no CL equivalent of FindSMsb
3071     return selectFirstBitHigh(ResVReg, ResType, I, /*IsSigned=*/true);
3072   case Intrinsic::spv_firstbitlow: // There is no CL equivlent of FindILsb
3073     return selectFirstBitLow(ResVReg, ResType, I);
3074   case Intrinsic::spv_group_memory_barrier_with_group_sync: {
3075     bool Result = true;
3076     auto MemSemConstant =
3077         buildI32Constant(SPIRV::MemorySemantics::SequentiallyConsistent, I);
3078     Register MemSemReg = MemSemConstant.first;
3079     Result &= MemSemConstant.second;
3080     auto ScopeConstant = buildI32Constant(SPIRV::Scope::Workgroup, I);
3081     Register ScopeReg = ScopeConstant.first;
3082     Result &= ScopeConstant.second;
3083     MachineBasicBlock &BB = *I.getParent();
3084     return Result &&
3085            BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpControlBarrier))
3086                .addUse(ScopeReg)
3087                .addUse(ScopeReg)
3088                .addUse(MemSemReg)
3089                .constrainAllUses(TII, TRI, RBI);
3090   }
3091   case Intrinsic::spv_lifetime_start:
3092   case Intrinsic::spv_lifetime_end: {
3093     unsigned Op = IID == Intrinsic::spv_lifetime_start ? SPIRV::OpLifetimeStart
3094                                                        : SPIRV::OpLifetimeStop;
3095     int64_t Size = I.getOperand(I.getNumExplicitDefs() + 1).getImm();
3096     Register PtrReg = I.getOperand(I.getNumExplicitDefs() + 2).getReg();
3097     if (Size == -1)
3098       Size = 0;
3099     return BuildMI(BB, I, I.getDebugLoc(), TII.get(Op))
3100         .addUse(PtrReg)
3101         .addImm(Size)
3102         .constrainAllUses(TII, TRI, RBI);
3103   }
3104   case Intrinsic::spv_saturate:
3105     return selectSaturate(ResVReg, ResType, I);
3106   case Intrinsic::spv_nclamp:
3107     return selectExtInst(ResVReg, ResType, I, CL::fclamp, GL::NClamp);
3108   case Intrinsic::spv_uclamp:
3109     return selectExtInst(ResVReg, ResType, I, CL::u_clamp, GL::UClamp);
3110   case Intrinsic::spv_sclamp:
3111     return selectExtInst(ResVReg, ResType, I, CL::s_clamp, GL::SClamp);
3112   case Intrinsic::spv_wave_active_countbits:
3113     return selectWaveActiveCountBits(ResVReg, ResType, I);
3114   case Intrinsic::spv_wave_all:
3115     return selectWaveOpInst(ResVReg, ResType, I, SPIRV::OpGroupNonUniformAll);
3116   case Intrinsic::spv_wave_any:
3117     return selectWaveOpInst(ResVReg, ResType, I, SPIRV::OpGroupNonUniformAny);
3118   case Intrinsic::spv_wave_is_first_lane:
3119     return selectWaveOpInst(ResVReg, ResType, I, SPIRV::OpGroupNonUniformElect);
3120   case Intrinsic::spv_wave_reduce_umax:
3121     return selectWaveReduceMax(ResVReg, ResType, I, /*IsUnsigned*/ true);
3122   case Intrinsic::spv_wave_reduce_max:
3123     return selectWaveReduceMax(ResVReg, ResType, I, /*IsUnsigned*/ false);
3124   case Intrinsic::spv_wave_reduce_sum:
3125     return selectWaveReduceSum(ResVReg, ResType, I);
3126   case Intrinsic::spv_wave_readlane:
3127     return selectWaveOpInst(ResVReg, ResType, I,
3128                             SPIRV::OpGroupNonUniformShuffle);
3129   case Intrinsic::spv_step:
3130     return selectExtInst(ResVReg, ResType, I, CL::step, GL::Step);
3131   case Intrinsic::spv_radians:
3132     return selectExtInst(ResVReg, ResType, I, CL::radians, GL::Radians);
3133   // Discard intrinsics which we do not expect to actually represent code after
3134   // lowering or intrinsics which are not implemented but should not crash when
3135   // found in a customer's LLVM IR input.
3136   case Intrinsic::instrprof_increment:
3137   case Intrinsic::instrprof_increment_step:
3138   case Intrinsic::instrprof_value_profile:
3139     break;
3140   // Discard internal intrinsics.
3141   case Intrinsic::spv_value_md:
3142     break;
3143   case Intrinsic::spv_resource_handlefrombinding: {
3144     return selectHandleFromBinding(ResVReg, ResType, I);
3145   }
3146   case Intrinsic::spv_resource_store_typedbuffer: {
3147     return selectImageWriteIntrinsic(I);
3148   }
3149   case Intrinsic::spv_resource_load_typedbuffer: {
3150     return selectReadImageIntrinsic(ResVReg, ResType, I);
3151   }
3152   case Intrinsic::spv_resource_getpointer: {
3153     return selectResourceGetPointer(ResVReg, ResType, I);
3154   }
3155   case Intrinsic::spv_discard: {
3156     return selectDiscard(ResVReg, ResType, I);
3157   }
3158   default: {
3159     std::string DiagMsg;
3160     raw_string_ostream OS(DiagMsg);
3161     I.print(OS);
3162     DiagMsg = "Intrinsic selection not implemented: " + DiagMsg;
3163     report_fatal_error(DiagMsg.c_str(), false);
3164   }
3165   }
3166   return true;
3167 }
3168 
3169 bool SPIRVInstructionSelector::selectHandleFromBinding(Register &ResVReg,
3170                                                        const SPIRVType *ResType,
3171                                                        MachineInstr &I) const {
3172   return true;
3173 }
3174 
3175 bool SPIRVInstructionSelector::selectReadImageIntrinsic(
3176     Register &ResVReg, const SPIRVType *ResType, MachineInstr &I) const {
3177 
3178   // If the load of the image is in a different basic block, then
3179   // this will generate invalid code. A proper solution is to move
3180   // the OpLoad from selectHandleFromBinding here. However, to do
3181   // that we will need to change the return type of the intrinsic.
3182   // We will do that when we can, but for now trying to move forward with other
3183   // issues.
3184   Register ImageReg = I.getOperand(2).getReg();
3185   auto *ImageDef = cast<GIntrinsic>(getVRegDef(*MRI, ImageReg));
3186   Register NewImageReg = MRI->createVirtualRegister(MRI->getRegClass(ImageReg));
3187   if (!loadHandleBeforePosition(NewImageReg, GR.getSPIRVTypeForVReg(ImageReg),
3188                                 *ImageDef, I)) {
3189     return false;
3190   }
3191 
3192   Register IdxReg = I.getOperand(3).getReg();
3193   DebugLoc Loc = I.getDebugLoc();
3194   MachineInstr &Pos = I;
3195 
3196   return generateImageRead(ResVReg, ResType, NewImageReg, IdxReg, Loc, Pos);
3197 }
3198 
3199 bool SPIRVInstructionSelector::generateImageRead(Register &ResVReg,
3200                                                  const SPIRVType *ResType,
3201                                                  Register ImageReg,
3202                                                  Register IdxReg, DebugLoc Loc,
3203                                                  MachineInstr &Pos) const {
3204   uint64_t ResultSize = GR.getScalarOrVectorComponentCount(ResType);
3205   if (ResultSize == 4) {
3206     return BuildMI(*Pos.getParent(), Pos, Loc, TII.get(SPIRV::OpImageRead))
3207         .addDef(ResVReg)
3208         .addUse(GR.getSPIRVTypeID(ResType))
3209         .addUse(ImageReg)
3210         .addUse(IdxReg)
3211         .constrainAllUses(TII, TRI, RBI);
3212   }
3213 
3214   SPIRVType *ReadType = widenTypeToVec4(ResType, Pos);
3215   Register ReadReg = MRI->createVirtualRegister(GR.getRegClass(ReadType));
3216   bool Succeed =
3217       BuildMI(*Pos.getParent(), Pos, Loc, TII.get(SPIRV::OpImageRead))
3218           .addDef(ReadReg)
3219           .addUse(GR.getSPIRVTypeID(ReadType))
3220           .addUse(ImageReg)
3221           .addUse(IdxReg)
3222           .constrainAllUses(TII, TRI, RBI);
3223   if (!Succeed)
3224     return false;
3225 
3226   if (ResultSize == 1) {
3227     return BuildMI(*Pos.getParent(), Pos, Loc,
3228                    TII.get(SPIRV::OpCompositeExtract))
3229         .addDef(ResVReg)
3230         .addUse(GR.getSPIRVTypeID(ResType))
3231         .addUse(ReadReg)
3232         .addImm(0)
3233         .constrainAllUses(TII, TRI, RBI);
3234   }
3235   return extractSubvector(ResVReg, ResType, ReadReg, Pos);
3236 }
3237 
3238 bool SPIRVInstructionSelector::selectResourceGetPointer(
3239     Register &ResVReg, const SPIRVType *ResType, MachineInstr &I) const {
3240 #ifdef ASSERT
3241   // For now, the operand is an image. This will change once we start handling
3242   // more resource types.
3243   Register ResourcePtr = I.getOperand(2).getReg();
3244   SPIRVType *RegType = GR.getResultType(ResourcePtr);
3245   assert(RegType->getOpcode() == SPIRV::OpTypeImage &&
3246          "Can only handle texel buffers for now.");
3247 #endif
3248 
3249   // For texel buffers, the index into the image is part of the OpImageRead or
3250   // OpImageWrite instructions. So we will do nothing in this case. This
3251   // intrinsic will be combined with the load or store when selecting the load
3252   // or store.
3253   return true;
3254 }
3255 
3256 bool SPIRVInstructionSelector::extractSubvector(
3257     Register &ResVReg, const SPIRVType *ResType, Register &ReadReg,
3258     MachineInstr &InsertionPoint) const {
3259   SPIRVType *InputType = GR.getResultType(ReadReg);
3260   [[maybe_unused]] uint64_t InputSize =
3261       GR.getScalarOrVectorComponentCount(InputType);
3262   uint64_t ResultSize = GR.getScalarOrVectorComponentCount(ResType);
3263   assert(InputSize > 1 && "The input must be a vector.");
3264   assert(ResultSize > 1 && "The result must be a vector.");
3265   assert(ResultSize < InputSize &&
3266          "Cannot extract more element than there are in the input.");
3267   SmallVector<Register> ComponentRegisters;
3268   SPIRVType *ScalarType = GR.getScalarOrVectorComponentType(ResType);
3269   const TargetRegisterClass *ScalarRegClass = GR.getRegClass(ScalarType);
3270   for (uint64_t I = 0; I < ResultSize; I++) {
3271     Register ComponentReg = MRI->createVirtualRegister(ScalarRegClass);
3272     bool Succeed = BuildMI(*InsertionPoint.getParent(), InsertionPoint,
3273                            InsertionPoint.getDebugLoc(),
3274                            TII.get(SPIRV::OpCompositeExtract))
3275                        .addDef(ComponentReg)
3276                        .addUse(ScalarType->getOperand(0).getReg())
3277                        .addUse(ReadReg)
3278                        .addImm(I)
3279                        .constrainAllUses(TII, TRI, RBI);
3280     if (!Succeed)
3281       return false;
3282     ComponentRegisters.emplace_back(ComponentReg);
3283   }
3284 
3285   MachineInstrBuilder MIB = BuildMI(*InsertionPoint.getParent(), InsertionPoint,
3286                                     InsertionPoint.getDebugLoc(),
3287                                     TII.get(SPIRV::OpCompositeConstruct))
3288                                 .addDef(ResVReg)
3289                                 .addUse(GR.getSPIRVTypeID(ResType));
3290 
3291   for (Register ComponentReg : ComponentRegisters)
3292     MIB.addUse(ComponentReg);
3293   return MIB.constrainAllUses(TII, TRI, RBI);
3294 }
3295 
3296 bool SPIRVInstructionSelector::selectImageWriteIntrinsic(
3297     MachineInstr &I) const {
3298   // If the load of the image is in a different basic block, then
3299   // this will generate invalid code. A proper solution is to move
3300   // the OpLoad from selectHandleFromBinding here. However, to do
3301   // that we will need to change the return type of the intrinsic.
3302   // We will do that when we can, but for now trying to move forward with other
3303   // issues.
3304   Register ImageReg = I.getOperand(1).getReg();
3305   auto *ImageDef = cast<GIntrinsic>(getVRegDef(*MRI, ImageReg));
3306   Register NewImageReg = MRI->createVirtualRegister(MRI->getRegClass(ImageReg));
3307   if (!loadHandleBeforePosition(NewImageReg, GR.getSPIRVTypeForVReg(ImageReg),
3308                                 *ImageDef, I)) {
3309     return false;
3310   }
3311 
3312   Register CoordinateReg = I.getOperand(2).getReg();
3313   Register DataReg = I.getOperand(3).getReg();
3314   assert(GR.getResultType(DataReg)->getOpcode() == SPIRV::OpTypeVector);
3315   assert(GR.getScalarOrVectorComponentCount(GR.getResultType(DataReg)) == 4);
3316   return BuildMI(*I.getParent(), I, I.getDebugLoc(),
3317                  TII.get(SPIRV::OpImageWrite))
3318       .addUse(NewImageReg)
3319       .addUse(CoordinateReg)
3320       .addUse(DataReg)
3321       .constrainAllUses(TII, TRI, RBI);
3322 }
3323 
3324 Register SPIRVInstructionSelector::buildPointerToResource(
3325     const SPIRVType *ResType, uint32_t Set, uint32_t Binding,
3326     uint32_t ArraySize, Register IndexReg, bool IsNonUniform,
3327     MachineIRBuilder MIRBuilder) const {
3328   if (ArraySize == 1)
3329     return GR.getOrCreateGlobalVariableWithBinding(ResType, Set, Binding,
3330                                                    MIRBuilder);
3331 
3332   const SPIRVType *VarType = GR.getOrCreateSPIRVArrayType(
3333       ResType, ArraySize, *MIRBuilder.getInsertPt(), TII);
3334   Register VarReg = GR.getOrCreateGlobalVariableWithBinding(
3335       VarType, Set, Binding, MIRBuilder);
3336 
3337   SPIRVType *ResPointerType = GR.getOrCreateSPIRVPointerType(
3338       ResType, MIRBuilder, SPIRV::StorageClass::UniformConstant);
3339 
3340   Register AcReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
3341   if (IsNonUniform) {
3342     // It is unclear which value needs to be marked an non-uniform, so both
3343     // the index and the access changed are decorated as non-uniform.
3344     buildOpDecorate(IndexReg, MIRBuilder, SPIRV::Decoration::NonUniformEXT, {});
3345     buildOpDecorate(AcReg, MIRBuilder, SPIRV::Decoration::NonUniformEXT, {});
3346   }
3347 
3348   MIRBuilder.buildInstr(SPIRV::OpAccessChain)
3349       .addDef(AcReg)
3350       .addUse(GR.getSPIRVTypeID(ResPointerType))
3351       .addUse(VarReg)
3352       .addUse(IndexReg);
3353 
3354   return AcReg;
3355 }
3356 
3357 bool SPIRVInstructionSelector::selectFirstBitSet16(
3358     Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
3359     unsigned ExtendOpcode, unsigned BitSetOpcode) const {
3360   Register ExtReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
3361   bool Result = selectOpWithSrcs(ExtReg, ResType, I, {I.getOperand(2).getReg()},
3362                                  ExtendOpcode);
3363 
3364   return Result &&
3365          selectFirstBitSet32(ResVReg, ResType, I, ExtReg, BitSetOpcode);
3366 }
3367 
3368 bool SPIRVInstructionSelector::selectFirstBitSet32(
3369     Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
3370     Register SrcReg, unsigned BitSetOpcode) const {
3371   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
3372       .addDef(ResVReg)
3373       .addUse(GR.getSPIRVTypeID(ResType))
3374       .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
3375       .addImm(BitSetOpcode)
3376       .addUse(SrcReg)
3377       .constrainAllUses(TII, TRI, RBI);
3378 }
3379 
3380 bool SPIRVInstructionSelector::selectFirstBitSet64Overflow(
3381     Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
3382     Register SrcReg, unsigned BitSetOpcode, bool SwapPrimarySide) const {
3383 
3384   // SPIR-V allow vectors of size 2,3,4 only. Calling with a larger vectors
3385   // requires creating a param register and return register with an invalid
3386   // vector size. If that is resolved, then this function can be used for
3387   // vectors of any component size.
3388   unsigned ComponentCount = GR.getScalarOrVectorComponentCount(ResType);
3389   assert(ComponentCount < 5 && "Vec 5+ will generate invalid SPIR-V ops");
3390 
3391   MachineIRBuilder MIRBuilder(I);
3392   SPIRVType *BaseType = GR.retrieveScalarOrVectorIntType(ResType);
3393   SPIRVType *I64Type = GR.getOrCreateSPIRVIntegerType(64, MIRBuilder);
3394   SPIRVType *I64x2Type = GR.getOrCreateSPIRVVectorType(I64Type, 2, MIRBuilder);
3395   SPIRVType *Vec2ResType =
3396       GR.getOrCreateSPIRVVectorType(BaseType, 2, MIRBuilder);
3397 
3398   std::vector<Register> PartialRegs;
3399 
3400   // Loops 0, 2, 4, ... but stops one loop early when ComponentCount is odd
3401   unsigned CurrentComponent = 0;
3402   for (; CurrentComponent + 1 < ComponentCount; CurrentComponent += 2) {
3403     // This register holds the firstbitX result for each of the i64x2 vectors
3404     // extracted from SrcReg
3405     Register BitSetResult =
3406         MRI->createVirtualRegister(GR.getRegClass(I64x2Type));
3407 
3408     auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
3409                        TII.get(SPIRV::OpVectorShuffle))
3410                    .addDef(BitSetResult)
3411                    .addUse(GR.getSPIRVTypeID(I64x2Type))
3412                    .addUse(SrcReg)
3413                    .addUse(SrcReg)
3414                    .addImm(CurrentComponent)
3415                    .addImm(CurrentComponent + 1);
3416 
3417     if (!MIB.constrainAllUses(TII, TRI, RBI))
3418       return false;
3419 
3420     Register SubVecBitSetReg =
3421         MRI->createVirtualRegister(GR.getRegClass(Vec2ResType));
3422 
3423     if (!selectFirstBitSet64(SubVecBitSetReg, Vec2ResType, I, BitSetResult,
3424                              BitSetOpcode, SwapPrimarySide))
3425       return false;
3426 
3427     PartialRegs.push_back(SubVecBitSetReg);
3428   }
3429 
3430   // On odd component counts we need to handle one more component
3431   if (CurrentComponent != ComponentCount) {
3432     bool ZeroAsNull = STI.isOpenCLEnv();
3433     Register FinalElemReg = MRI->createVirtualRegister(GR.getRegClass(I64Type));
3434     Register ConstIntLastIdx = GR.getOrCreateConstInt(
3435         ComponentCount - 1, I, BaseType, TII, ZeroAsNull);
3436 
3437     if (!selectOpWithSrcs(FinalElemReg, I64Type, I, {SrcReg, ConstIntLastIdx},
3438                           SPIRV::OpVectorExtractDynamic))
3439       return false;
3440 
3441     Register FinalElemBitSetReg =
3442         MRI->createVirtualRegister(GR.getRegClass(BaseType));
3443 
3444     if (!selectFirstBitSet64(FinalElemBitSetReg, BaseType, I, FinalElemReg,
3445                              BitSetOpcode, SwapPrimarySide))
3446       return false;
3447 
3448     PartialRegs.push_back(FinalElemBitSetReg);
3449   }
3450 
3451   // Join all the resulting registers back into the return type in order
3452   // (ie i32x2, i32x2, i32x1 -> i32x5)
3453   return selectOpWithSrcs(ResVReg, ResType, I, PartialRegs,
3454                           SPIRV::OpCompositeConstruct);
3455 }
3456 
3457 bool SPIRVInstructionSelector::selectFirstBitSet64(
3458     Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
3459     Register SrcReg, unsigned BitSetOpcode, bool SwapPrimarySide) const {
3460   unsigned ComponentCount = GR.getScalarOrVectorComponentCount(ResType);
3461   SPIRVType *BaseType = GR.retrieveScalarOrVectorIntType(ResType);
3462   bool ZeroAsNull = STI.isOpenCLEnv();
3463   Register ConstIntZero =
3464       GR.getOrCreateConstInt(0, I, BaseType, TII, ZeroAsNull);
3465   Register ConstIntOne =
3466       GR.getOrCreateConstInt(1, I, BaseType, TII, ZeroAsNull);
3467 
3468   // SPIRV doesn't support vectors with more than 4 components. Since the
3469   // algoritm below converts i64 -> i32x2 and i64x4 -> i32x8 it can only
3470   // operate on vectors with 2 or less components. When largers vectors are
3471   // seen. Split them, recurse, then recombine them.
3472   if (ComponentCount > 2) {
3473     return selectFirstBitSet64Overflow(ResVReg, ResType, I, SrcReg,
3474                                        BitSetOpcode, SwapPrimarySide);
3475   }
3476 
3477   // 1. Split int64 into 2 pieces using a bitcast
3478   MachineIRBuilder MIRBuilder(I);
3479   SPIRVType *PostCastType =
3480       GR.getOrCreateSPIRVVectorType(BaseType, 2 * ComponentCount, MIRBuilder);
3481   Register BitcastReg =
3482       MRI->createVirtualRegister(GR.getRegClass(PostCastType));
3483 
3484   if (!selectOpWithSrcs(BitcastReg, PostCastType, I, {SrcReg},
3485                         SPIRV::OpBitcast))
3486     return false;
3487 
3488   // 2. Find the first set bit from the primary side for all the pieces in #1
3489   Register FBSReg = MRI->createVirtualRegister(GR.getRegClass(PostCastType));
3490   if (!selectFirstBitSet32(FBSReg, PostCastType, I, BitcastReg, BitSetOpcode))
3491     return false;
3492 
3493   // 3. Split result vector into high bits and low bits
3494   Register HighReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
3495   Register LowReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
3496 
3497   bool IsScalarRes = ResType->getOpcode() != SPIRV::OpTypeVector;
3498   if (IsScalarRes) {
3499     // if scalar do a vector extract
3500     if (!selectOpWithSrcs(HighReg, ResType, I, {FBSReg, ConstIntZero},
3501                           SPIRV::OpVectorExtractDynamic))
3502       return false;
3503     if (!selectOpWithSrcs(LowReg, ResType, I, {FBSReg, ConstIntOne},
3504                           SPIRV::OpVectorExtractDynamic))
3505       return false;
3506   } else {
3507     // if vector do a shufflevector
3508     auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
3509                        TII.get(SPIRV::OpVectorShuffle))
3510                    .addDef(HighReg)
3511                    .addUse(GR.getSPIRVTypeID(ResType))
3512                    .addUse(FBSReg)
3513                    // Per the spec, repeat the vector if only one vec is needed
3514                    .addUse(FBSReg);
3515 
3516     // high bits are stored in even indexes. Extract them from FBSReg
3517     for (unsigned J = 0; J < ComponentCount * 2; J += 2) {
3518       MIB.addImm(J);
3519     }
3520 
3521     if (!MIB.constrainAllUses(TII, TRI, RBI))
3522       return false;
3523 
3524     MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
3525                   TII.get(SPIRV::OpVectorShuffle))
3526               .addDef(LowReg)
3527               .addUse(GR.getSPIRVTypeID(ResType))
3528               .addUse(FBSReg)
3529               // Per the spec, repeat the vector if only one vec is needed
3530               .addUse(FBSReg);
3531 
3532     // low bits are stored in odd indexes. Extract them from FBSReg
3533     for (unsigned J = 1; J < ComponentCount * 2; J += 2) {
3534       MIB.addImm(J);
3535     }
3536     if (!MIB.constrainAllUses(TII, TRI, RBI))
3537       return false;
3538   }
3539 
3540   // 4. Check the result. When primary bits == -1 use secondary, otherwise use
3541   // primary
3542   SPIRVType *BoolType = GR.getOrCreateSPIRVBoolType(I, TII);
3543   Register NegOneReg;
3544   Register Reg0;
3545   Register Reg32;
3546   unsigned SelectOp;
3547   unsigned AddOp;
3548 
3549   if (IsScalarRes) {
3550     NegOneReg =
3551         GR.getOrCreateConstInt((unsigned)-1, I, ResType, TII, ZeroAsNull);
3552     Reg0 = GR.getOrCreateConstInt(0, I, ResType, TII, ZeroAsNull);
3553     Reg32 = GR.getOrCreateConstInt(32, I, ResType, TII, ZeroAsNull);
3554     SelectOp = SPIRV::OpSelectSISCond;
3555     AddOp = SPIRV::OpIAddS;
3556   } else {
3557     BoolType =
3558         GR.getOrCreateSPIRVVectorType(BoolType, ComponentCount, MIRBuilder);
3559     NegOneReg =
3560         GR.getOrCreateConstVector((unsigned)-1, I, ResType, TII, ZeroAsNull);
3561     Reg0 = GR.getOrCreateConstVector(0, I, ResType, TII, ZeroAsNull);
3562     Reg32 = GR.getOrCreateConstVector(32, I, ResType, TII, ZeroAsNull);
3563     SelectOp = SPIRV::OpSelectVIVCond;
3564     AddOp = SPIRV::OpIAddV;
3565   }
3566 
3567   Register PrimaryReg = HighReg;
3568   Register SecondaryReg = LowReg;
3569   Register PrimaryShiftReg = Reg32;
3570   Register SecondaryShiftReg = Reg0;
3571 
3572   // By default the emitted opcodes check for the set bit from the MSB side.
3573   // Setting SwapPrimarySide checks the set bit from the LSB side
3574   if (SwapPrimarySide) {
3575     PrimaryReg = LowReg;
3576     SecondaryReg = HighReg;
3577     PrimaryShiftReg = Reg0;
3578     SecondaryShiftReg = Reg32;
3579   }
3580 
3581   // Check if the primary bits are == -1
3582   Register BReg = MRI->createVirtualRegister(GR.getRegClass(BoolType));
3583   if (!selectOpWithSrcs(BReg, BoolType, I, {PrimaryReg, NegOneReg},
3584                         SPIRV::OpIEqual))
3585     return false;
3586 
3587   // Select secondary bits if true in BReg, otherwise primary bits
3588   Register TmpReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
3589   if (!selectOpWithSrcs(TmpReg, ResType, I, {BReg, SecondaryReg, PrimaryReg},
3590                         SelectOp))
3591     return false;
3592 
3593   // 5. Add 32 when high bits are used, otherwise 0 for low bits
3594   Register ValReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
3595   if (!selectOpWithSrcs(ValReg, ResType, I,
3596                         {BReg, SecondaryShiftReg, PrimaryShiftReg}, SelectOp))
3597     return false;
3598 
3599   return selectOpWithSrcs(ResVReg, ResType, I, {ValReg, TmpReg}, AddOp);
3600 }
3601 
3602 bool SPIRVInstructionSelector::selectFirstBitHigh(Register ResVReg,
3603                                                   const SPIRVType *ResType,
3604                                                   MachineInstr &I,
3605                                                   bool IsSigned) const {
3606   // FindUMsb and FindSMsb intrinsics only support 32 bit integers
3607   Register OpReg = I.getOperand(2).getReg();
3608   SPIRVType *OpType = GR.getSPIRVTypeForVReg(OpReg);
3609   // zero or sign extend
3610   unsigned ExtendOpcode = IsSigned ? SPIRV::OpSConvert : SPIRV::OpUConvert;
3611   unsigned BitSetOpcode = IsSigned ? GL::FindSMsb : GL::FindUMsb;
3612 
3613   switch (GR.getScalarOrVectorBitWidth(OpType)) {
3614   case 16:
3615     return selectFirstBitSet16(ResVReg, ResType, I, ExtendOpcode, BitSetOpcode);
3616   case 32:
3617     return selectFirstBitSet32(ResVReg, ResType, I, OpReg, BitSetOpcode);
3618   case 64:
3619     return selectFirstBitSet64(ResVReg, ResType, I, OpReg, BitSetOpcode,
3620                                /*SwapPrimarySide=*/false);
3621   default:
3622     report_fatal_error(
3623         "spv_firstbituhigh and spv_firstbitshigh only support 16,32,64 bits.");
3624   }
3625 }
3626 
3627 bool SPIRVInstructionSelector::selectFirstBitLow(Register ResVReg,
3628                                                  const SPIRVType *ResType,
3629                                                  MachineInstr &I) const {
3630   // FindILsb intrinsic only supports 32 bit integers
3631   Register OpReg = I.getOperand(2).getReg();
3632   SPIRVType *OpType = GR.getSPIRVTypeForVReg(OpReg);
3633   // OpUConvert treats the operand bits as an unsigned i16 and zero extends it
3634   // to an unsigned i32. As this leaves all the least significant bits unchanged
3635   // so the first set bit from the LSB side doesn't change.
3636   unsigned ExtendOpcode = SPIRV::OpUConvert;
3637   unsigned BitSetOpcode = GL::FindILsb;
3638 
3639   switch (GR.getScalarOrVectorBitWidth(OpType)) {
3640   case 16:
3641     return selectFirstBitSet16(ResVReg, ResType, I, ExtendOpcode, BitSetOpcode);
3642   case 32:
3643     return selectFirstBitSet32(ResVReg, ResType, I, OpReg, BitSetOpcode);
3644   case 64:
3645     return selectFirstBitSet64(ResVReg, ResType, I, OpReg, BitSetOpcode,
3646                                /*SwapPrimarySide=*/true);
3647   default:
3648     report_fatal_error("spv_firstbitlow only supports 16,32,64 bits.");
3649   }
3650 }
3651 
3652 bool SPIRVInstructionSelector::selectAllocaArray(Register ResVReg,
3653                                                  const SPIRVType *ResType,
3654                                                  MachineInstr &I) const {
3655   // there was an allocation size parameter to the allocation instruction
3656   // that is not 1
3657   MachineBasicBlock &BB = *I.getParent();
3658   bool Res = BuildMI(BB, I, I.getDebugLoc(),
3659                      TII.get(SPIRV::OpVariableLengthArrayINTEL))
3660                  .addDef(ResVReg)
3661                  .addUse(GR.getSPIRVTypeID(ResType))
3662                  .addUse(I.getOperand(2).getReg())
3663                  .constrainAllUses(TII, TRI, RBI);
3664   if (!STI.isVulkanEnv()) {
3665     unsigned Alignment = I.getOperand(3).getImm();
3666     buildOpDecorate(ResVReg, I, TII, SPIRV::Decoration::Alignment, {Alignment});
3667   }
3668   return Res;
3669 }
3670 
3671 bool SPIRVInstructionSelector::selectFrameIndex(Register ResVReg,
3672                                                 const SPIRVType *ResType,
3673                                                 MachineInstr &I) const {
3674   // Change order of instructions if needed: all OpVariable instructions in a
3675   // function must be the first instructions in the first block
3676   auto It = getOpVariableMBBIt(I);
3677   bool Res = BuildMI(*It->getParent(), It, It->getDebugLoc(),
3678                      TII.get(SPIRV::OpVariable))
3679                  .addDef(ResVReg)
3680                  .addUse(GR.getSPIRVTypeID(ResType))
3681                  .addImm(static_cast<uint32_t>(SPIRV::StorageClass::Function))
3682                  .constrainAllUses(TII, TRI, RBI);
3683   if (!STI.isVulkanEnv()) {
3684     unsigned Alignment = I.getOperand(2).getImm();
3685     buildOpDecorate(ResVReg, *It, TII, SPIRV::Decoration::Alignment,
3686                     {Alignment});
3687   }
3688   return Res;
3689 }
3690 
3691 bool SPIRVInstructionSelector::selectBranch(MachineInstr &I) const {
3692   // InstructionSelector walks backwards through the instructions. We can use
3693   // both a G_BR and a G_BRCOND to create an OpBranchConditional. We hit G_BR
3694   // first, so can generate an OpBranchConditional here. If there is no
3695   // G_BRCOND, we just use OpBranch for a regular unconditional branch.
3696   const MachineInstr *PrevI = I.getPrevNode();
3697   MachineBasicBlock &MBB = *I.getParent();
3698   if (PrevI != nullptr && PrevI->getOpcode() == TargetOpcode::G_BRCOND) {
3699     return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranchConditional))
3700         .addUse(PrevI->getOperand(0).getReg())
3701         .addMBB(PrevI->getOperand(1).getMBB())
3702         .addMBB(I.getOperand(0).getMBB())
3703         .constrainAllUses(TII, TRI, RBI);
3704   }
3705   return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranch))
3706       .addMBB(I.getOperand(0).getMBB())
3707       .constrainAllUses(TII, TRI, RBI);
3708 }
3709 
3710 bool SPIRVInstructionSelector::selectBranchCond(MachineInstr &I) const {
3711   // InstructionSelector walks backwards through the instructions. For an
3712   // explicit conditional branch with no fallthrough, we use both a G_BR and a
3713   // G_BRCOND to create an OpBranchConditional. We should hit G_BR first, and
3714   // generate the OpBranchConditional in selectBranch above.
3715   //
3716   // If an OpBranchConditional has been generated, we simply return, as the work
3717   // is alread done. If there is no OpBranchConditional, LLVM must be relying on
3718   // implicit fallthrough to the next basic block, so we need to create an
3719   // OpBranchConditional with an explicit "false" argument pointing to the next
3720   // basic block that LLVM would fall through to.
3721   const MachineInstr *NextI = I.getNextNode();
3722   // Check if this has already been successfully selected.
3723   if (NextI != nullptr && NextI->getOpcode() == SPIRV::OpBranchConditional)
3724     return true;
3725   // Must be relying on implicit block fallthrough, so generate an
3726   // OpBranchConditional with the "next" basic block as the "false" target.
3727   MachineBasicBlock &MBB = *I.getParent();
3728   unsigned NextMBBNum = MBB.getNextNode()->getNumber();
3729   MachineBasicBlock *NextMBB = I.getMF()->getBlockNumbered(NextMBBNum);
3730   return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranchConditional))
3731       .addUse(I.getOperand(0).getReg())
3732       .addMBB(I.getOperand(1).getMBB())
3733       .addMBB(NextMBB)
3734       .constrainAllUses(TII, TRI, RBI);
3735 }
3736 
3737 bool SPIRVInstructionSelector::selectPhi(Register ResVReg,
3738                                          const SPIRVType *ResType,
3739                                          MachineInstr &I) const {
3740   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpPhi))
3741                  .addDef(ResVReg)
3742                  .addUse(GR.getSPIRVTypeID(ResType));
3743   const unsigned NumOps = I.getNumOperands();
3744   for (unsigned i = 1; i < NumOps; i += 2) {
3745     MIB.addUse(I.getOperand(i + 0).getReg());
3746     MIB.addMBB(I.getOperand(i + 1).getMBB());
3747   }
3748   bool Res = MIB.constrainAllUses(TII, TRI, RBI);
3749   MIB->setDesc(TII.get(TargetOpcode::PHI));
3750   MIB->removeOperand(1);
3751   return Res;
3752 }
3753 
3754 bool SPIRVInstructionSelector::selectGlobalValue(
3755     Register ResVReg, MachineInstr &I, const MachineInstr *Init) const {
3756   // FIXME: don't use MachineIRBuilder here, replace it with BuildMI.
3757   MachineIRBuilder MIRBuilder(I);
3758   const GlobalValue *GV = I.getOperand(1).getGlobal();
3759   Type *GVType = toTypedPointer(GR.getDeducedGlobalValueType(GV));
3760   SPIRVType *PointerBaseType;
3761   if (GVType->isArrayTy()) {
3762     SPIRVType *ArrayElementType =
3763         GR.getOrCreateSPIRVType(GVType->getArrayElementType(), MIRBuilder,
3764                                 SPIRV::AccessQualifier::ReadWrite, false);
3765     PointerBaseType = GR.getOrCreateSPIRVArrayType(
3766         ArrayElementType, GVType->getArrayNumElements(), I, TII);
3767   } else {
3768     PointerBaseType = GR.getOrCreateSPIRVType(
3769         GVType, MIRBuilder, SPIRV::AccessQualifier::ReadWrite, false);
3770   }
3771 
3772   std::string GlobalIdent;
3773   if (!GV->hasName()) {
3774     unsigned &ID = UnnamedGlobalIDs[GV];
3775     if (ID == 0)
3776       ID = UnnamedGlobalIDs.size();
3777     GlobalIdent = "__unnamed_" + Twine(ID).str();
3778   } else {
3779     GlobalIdent = GV->getName();
3780   }
3781 
3782   // Behaviour of functions as operands depends on availability of the
3783   // corresponding extension (SPV_INTEL_function_pointers):
3784   // - If there is an extension to operate with functions as operands:
3785   // We create a proper constant operand and evaluate a correct type for a
3786   // function pointer.
3787   // - Without the required extension:
3788   // We have functions as operands in tests with blocks of instruction e.g. in
3789   // transcoding/global_block.ll. These operands are not used and should be
3790   // substituted by zero constants. Their type is expected to be always
3791   // OpTypePointer Function %uchar.
3792   if (isa<Function>(GV)) {
3793     const Constant *ConstVal = GV;
3794     MachineBasicBlock &BB = *I.getParent();
3795     Register NewReg = GR.find(ConstVal, GR.CurMF);
3796     if (!NewReg.isValid()) {
3797       Register NewReg = ResVReg;
3798       GR.add(ConstVal, GR.CurMF, NewReg);
3799       const Function *GVFun =
3800           STI.canUseExtension(SPIRV::Extension::SPV_INTEL_function_pointers)
3801               ? dyn_cast<Function>(GV)
3802               : nullptr;
3803       SPIRVType *ResType = GR.getOrCreateSPIRVPointerType(
3804           PointerBaseType, I, TII,
3805           GVFun ? SPIRV::StorageClass::CodeSectionINTEL
3806                 : addressSpaceToStorageClass(GV->getAddressSpace(), STI));
3807       if (GVFun) {
3808         // References to a function via function pointers generate virtual
3809         // registers without a definition. We will resolve it later, during
3810         // module analysis stage.
3811         Register ResTypeReg = GR.getSPIRVTypeID(ResType);
3812         MachineRegisterInfo *MRI = MIRBuilder.getMRI();
3813         Register FuncVReg =
3814             MRI->createGenericVirtualRegister(GR.getRegType(ResType));
3815         MRI->setRegClass(FuncVReg, &SPIRV::pIDRegClass);
3816         MachineInstrBuilder MIB1 =
3817             BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpUndef))
3818                 .addDef(FuncVReg)
3819                 .addUse(ResTypeReg);
3820         MachineInstrBuilder MIB2 =
3821             BuildMI(BB, I, I.getDebugLoc(),
3822                     TII.get(SPIRV::OpConstantFunctionPointerINTEL))
3823                 .addDef(NewReg)
3824                 .addUse(ResTypeReg)
3825                 .addUse(FuncVReg);
3826         // mapping the function pointer to the used Function
3827         GR.recordFunctionPointer(&MIB2.getInstr()->getOperand(2), GVFun);
3828         return MIB1.constrainAllUses(TII, TRI, RBI) &&
3829                MIB2.constrainAllUses(TII, TRI, RBI);
3830       }
3831       return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
3832           .addDef(NewReg)
3833           .addUse(GR.getSPIRVTypeID(ResType))
3834           .constrainAllUses(TII, TRI, RBI);
3835     }
3836     assert(NewReg != ResVReg);
3837     return BuildCOPY(ResVReg, NewReg, I);
3838   }
3839   auto GlobalVar = cast<GlobalVariable>(GV);
3840   assert(GlobalVar->getName() != "llvm.global.annotations");
3841 
3842   // Skip empty declaration for GVs with initializers till we get the decl with
3843   // passed initializer.
3844   if (hasInitializer(GlobalVar) && !Init)
3845     return true;
3846 
3847   bool HasLnkTy = !GV->hasInternalLinkage() && !GV->hasPrivateLinkage();
3848   SPIRV::LinkageType::LinkageType LnkType =
3849       GV->isDeclarationForLinker()
3850           ? SPIRV::LinkageType::Import
3851           : (GV->hasLinkOnceODRLinkage() &&
3852                      STI.canUseExtension(SPIRV::Extension::SPV_KHR_linkonce_odr)
3853                  ? SPIRV::LinkageType::LinkOnceODR
3854                  : SPIRV::LinkageType::Export);
3855 
3856   const unsigned AddrSpace = GV->getAddressSpace();
3857   SPIRV::StorageClass::StorageClass StorageClass =
3858       addressSpaceToStorageClass(AddrSpace, STI);
3859   SPIRVType *ResType =
3860       GR.getOrCreateSPIRVPointerType(PointerBaseType, I, TII, StorageClass);
3861   Register Reg = GR.buildGlobalVariable(
3862       ResVReg, ResType, GlobalIdent, GV, StorageClass, Init,
3863       GlobalVar->isConstant(), HasLnkTy, LnkType, MIRBuilder, true);
3864   return Reg.isValid();
3865 }
3866 
3867 bool SPIRVInstructionSelector::selectLog10(Register ResVReg,
3868                                            const SPIRVType *ResType,
3869                                            MachineInstr &I) const {
3870   if (STI.canUseExtInstSet(SPIRV::InstructionSet::OpenCL_std)) {
3871     return selectExtInst(ResVReg, ResType, I, CL::log10);
3872   }
3873 
3874   // There is no log10 instruction in the GLSL Extended Instruction set, so it
3875   // is implemented as:
3876   // log10(x) = log2(x) * (1 / log2(10))
3877   //          = log2(x) * 0.30103
3878 
3879   MachineIRBuilder MIRBuilder(I);
3880   MachineBasicBlock &BB = *I.getParent();
3881 
3882   // Build log2(x).
3883   Register VarReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
3884   bool Result =
3885       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
3886           .addDef(VarReg)
3887           .addUse(GR.getSPIRVTypeID(ResType))
3888           .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
3889           .addImm(GL::Log2)
3890           .add(I.getOperand(1))
3891           .constrainAllUses(TII, TRI, RBI);
3892 
3893   // Build 0.30103.
3894   assert(ResType->getOpcode() == SPIRV::OpTypeVector ||
3895          ResType->getOpcode() == SPIRV::OpTypeFloat);
3896   // TODO: Add matrix implementation once supported by the HLSL frontend.
3897   const SPIRVType *SpirvScalarType =
3898       ResType->getOpcode() == SPIRV::OpTypeVector
3899           ? GR.getSPIRVTypeForVReg(ResType->getOperand(1).getReg())
3900           : ResType;
3901   Register ScaleReg =
3902       GR.buildConstantFP(APFloat(0.30103f), MIRBuilder, SpirvScalarType);
3903 
3904   // Multiply log2(x) by 0.30103 to get log10(x) result.
3905   auto Opcode = ResType->getOpcode() == SPIRV::OpTypeVector
3906                     ? SPIRV::OpVectorTimesScalar
3907                     : SPIRV::OpFMulS;
3908   return Result && BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
3909                        .addDef(ResVReg)
3910                        .addUse(GR.getSPIRVTypeID(ResType))
3911                        .addUse(VarReg)
3912                        .addUse(ScaleReg)
3913                        .constrainAllUses(TII, TRI, RBI);
3914 }
3915 
3916 // Generate the instructions to load 3-element vector builtin input
3917 // IDs/Indices.
3918 // Like: GlobalInvocationId, LocalInvocationId, etc....
3919 bool SPIRVInstructionSelector::loadVec3BuiltinInputID(
3920     SPIRV::BuiltIn::BuiltIn BuiltInValue, Register ResVReg,
3921     const SPIRVType *ResType, MachineInstr &I) const {
3922   MachineIRBuilder MIRBuilder(I);
3923   const SPIRVType *U32Type = GR.getOrCreateSPIRVIntegerType(32, MIRBuilder);
3924   const SPIRVType *Vec3Ty =
3925       GR.getOrCreateSPIRVVectorType(U32Type, 3, MIRBuilder);
3926   const SPIRVType *PtrType = GR.getOrCreateSPIRVPointerType(
3927       Vec3Ty, MIRBuilder, SPIRV::StorageClass::Input);
3928 
3929   // Create new register for the input ID builtin variable.
3930   Register NewRegister =
3931       MIRBuilder.getMRI()->createVirtualRegister(&SPIRV::iIDRegClass);
3932   MIRBuilder.getMRI()->setType(NewRegister, LLT::pointer(0, 64));
3933   GR.assignSPIRVTypeToVReg(PtrType, NewRegister, MIRBuilder.getMF());
3934 
3935   // Build global variable with the necessary decorations for the input ID
3936   // builtin variable.
3937   Register Variable = GR.buildGlobalVariable(
3938       NewRegister, PtrType, getLinkStringForBuiltIn(BuiltInValue), nullptr,
3939       SPIRV::StorageClass::Input, nullptr, true, true,
3940       SPIRV::LinkageType::Import, MIRBuilder, false);
3941 
3942   // Create new register for loading value.
3943   MachineRegisterInfo *MRI = MIRBuilder.getMRI();
3944   Register LoadedRegister = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
3945   MIRBuilder.getMRI()->setType(LoadedRegister, LLT::pointer(0, 64));
3946   GR.assignSPIRVTypeToVReg(Vec3Ty, LoadedRegister, MIRBuilder.getMF());
3947 
3948   // Load v3uint value from the global variable.
3949   bool Result =
3950       BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
3951           .addDef(LoadedRegister)
3952           .addUse(GR.getSPIRVTypeID(Vec3Ty))
3953           .addUse(Variable);
3954 
3955   // Get the input ID index. Expecting operand is a constant immediate value,
3956   // wrapped in a type assignment.
3957   assert(I.getOperand(2).isReg());
3958   const uint32_t ThreadId = foldImm(I.getOperand(2), MRI);
3959 
3960   // Extract the input ID from the loaded vector value.
3961   MachineBasicBlock &BB = *I.getParent();
3962   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
3963                  .addDef(ResVReg)
3964                  .addUse(GR.getSPIRVTypeID(ResType))
3965                  .addUse(LoadedRegister)
3966                  .addImm(ThreadId);
3967   return Result && MIB.constrainAllUses(TII, TRI, RBI);
3968 }
3969 
3970 SPIRVType *SPIRVInstructionSelector::widenTypeToVec4(const SPIRVType *Type,
3971                                                      MachineInstr &I) const {
3972   MachineIRBuilder MIRBuilder(I);
3973   if (Type->getOpcode() != SPIRV::OpTypeVector)
3974     return GR.getOrCreateSPIRVVectorType(Type, 4, MIRBuilder);
3975 
3976   uint64_t VectorSize = Type->getOperand(2).getImm();
3977   if (VectorSize == 4)
3978     return Type;
3979 
3980   Register ScalarTypeReg = Type->getOperand(1).getReg();
3981   const SPIRVType *ScalarType = GR.getSPIRVTypeForVReg(ScalarTypeReg);
3982   return GR.getOrCreateSPIRVVectorType(ScalarType, 4, MIRBuilder);
3983 }
3984 
3985 bool SPIRVInstructionSelector::loadHandleBeforePosition(
3986     Register &HandleReg, const SPIRVType *ResType, GIntrinsic &HandleDef,
3987     MachineInstr &Pos) const {
3988 
3989   assert(HandleDef.getIntrinsicID() ==
3990          Intrinsic::spv_resource_handlefrombinding);
3991   uint32_t Set = foldImm(HandleDef.getOperand(2), MRI);
3992   uint32_t Binding = foldImm(HandleDef.getOperand(3), MRI);
3993   uint32_t ArraySize = foldImm(HandleDef.getOperand(4), MRI);
3994   Register IndexReg = HandleDef.getOperand(5).getReg();
3995   bool IsNonUniform = ArraySize > 1 && foldImm(HandleDef.getOperand(6), MRI);
3996 
3997   MachineIRBuilder MIRBuilder(HandleDef);
3998   Register VarReg = buildPointerToResource(ResType, Set, Binding, ArraySize,
3999                                            IndexReg, IsNonUniform, MIRBuilder);
4000 
4001   if (IsNonUniform)
4002     buildOpDecorate(HandleReg, HandleDef, TII, SPIRV::Decoration::NonUniformEXT,
4003                     {});
4004 
4005   // TODO: For now we assume the resource is an image, which needs to be
4006   // loaded to get the handle. That will not be true for storage buffers.
4007   return BuildMI(*Pos.getParent(), Pos, HandleDef.getDebugLoc(),
4008                  TII.get(SPIRV::OpLoad))
4009       .addDef(HandleReg)
4010       .addUse(GR.getSPIRVTypeID(ResType))
4011       .addUse(VarReg)
4012       .constrainAllUses(TII, TRI, RBI);
4013 }
4014 
4015 namespace llvm {
4016 InstructionSelector *
4017 createSPIRVInstructionSelector(const SPIRVTargetMachine &TM,
4018                                const SPIRVSubtarget &Subtarget,
4019                                const RegisterBankInfo &RBI) {
4020   return new SPIRVInstructionSelector(TM, Subtarget, RBI);
4021 }
4022 } // namespace llvm
4023