xref: /llvm-project/llvm/lib/Target/SPIRV/SPIRVInstructionSelector.cpp (revision a93cbd4e762799206ae6e6c45f4a7d0da7e56513)
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/CodeGen/GlobalISel/GIMatchTableExecutorImpl.h"
26 #include "llvm/CodeGen/GlobalISel/GenericMachineInstrs.h"
27 #include "llvm/CodeGen/GlobalISel/InstructionSelector.h"
28 #include "llvm/CodeGen/MachineInstrBuilder.h"
29 #include "llvm/CodeGen/MachineModuleInfoImpls.h"
30 #include "llvm/CodeGen/MachineRegisterInfo.h"
31 #include "llvm/CodeGen/Register.h"
32 #include "llvm/CodeGen/TargetOpcodes.h"
33 #include "llvm/IR/IntrinsicsSPIRV.h"
34 #include "llvm/Support/Debug.h"
35 
36 #define DEBUG_TYPE "spirv-isel"
37 
38 using namespace llvm;
39 namespace CL = SPIRV::OpenCLExtInst;
40 namespace GL = SPIRV::GLSLExtInst;
41 
42 using ExtInstList =
43     std::vector<std::pair<SPIRV::InstructionSet::InstructionSet, uint32_t>>;
44 
45 namespace {
46 
47 #define GET_GLOBALISEL_PREDICATE_BITSET
48 #include "SPIRVGenGlobalISel.inc"
49 #undef GET_GLOBALISEL_PREDICATE_BITSET
50 
51 class SPIRVInstructionSelector : public InstructionSelector {
52   const SPIRVSubtarget &STI;
53   const SPIRVInstrInfo &TII;
54   const SPIRVRegisterInfo &TRI;
55   const RegisterBankInfo &RBI;
56   SPIRVGlobalRegistry &GR;
57   MachineRegisterInfo *MRI;
58   MachineFunction *HasVRegsReset = nullptr;
59 
60   /// We need to keep track of the number we give to anonymous global values to
61   /// generate the same name every time when this is needed.
62   mutable DenseMap<const GlobalValue *, unsigned> UnnamedGlobalIDs;
63 
64 public:
65   SPIRVInstructionSelector(const SPIRVTargetMachine &TM,
66                            const SPIRVSubtarget &ST,
67                            const RegisterBankInfo &RBI);
68   void setupMF(MachineFunction &MF, GISelKnownBits *KB,
69                CodeGenCoverage *CoverageInfo, ProfileSummaryInfo *PSI,
70                BlockFrequencyInfo *BFI) override;
71   // Common selection code. Instruction-specific selection occurs in spvSelect.
72   bool select(MachineInstr &I) override;
73   static const char *getName() { return DEBUG_TYPE; }
74 
75 #define GET_GLOBALISEL_PREDICATES_DECL
76 #include "SPIRVGenGlobalISel.inc"
77 #undef GET_GLOBALISEL_PREDICATES_DECL
78 
79 #define GET_GLOBALISEL_TEMPORARIES_DECL
80 #include "SPIRVGenGlobalISel.inc"
81 #undef GET_GLOBALISEL_TEMPORARIES_DECL
82 
83 private:
84   void resetVRegsType(MachineFunction &MF);
85 
86   // tblgen-erated 'select' implementation, used as the initial selector for
87   // the patterns that don't require complex C++.
88   bool selectImpl(MachineInstr &I, CodeGenCoverage &CoverageInfo) const;
89 
90   // All instruction-specific selection that didn't happen in "select()".
91   // Is basically a large Switch/Case delegating to all other select method.
92   bool spvSelect(Register ResVReg, const SPIRVType *ResType,
93                  MachineInstr &I) const;
94 
95   bool selectFirstBitHigh(Register ResVReg, const SPIRVType *ResType,
96                           MachineInstr &I, bool IsSigned) const;
97 
98   bool selectFirstBitHigh16(Register ResVReg, const SPIRVType *ResType,
99                             MachineInstr &I, bool IsSigned) const;
100 
101   bool selectFirstBitHigh32(Register ResVReg, const SPIRVType *ResType,
102                             MachineInstr &I, Register SrcReg,
103                             bool IsSigned) const;
104 
105   bool selectFirstBitHigh64(Register ResVReg, const SPIRVType *ResType,
106                             MachineInstr &I, bool IsSigned) const;
107 
108   bool selectGlobalValue(Register ResVReg, MachineInstr &I,
109                          const MachineInstr *Init = nullptr) const;
110 
111   bool selectNAryOpWithSrcs(Register ResVReg, const SPIRVType *ResType,
112                             MachineInstr &I, std::vector<Register> SrcRegs,
113                             unsigned Opcode) const;
114 
115   bool selectUnOpWithSrc(Register ResVReg, const SPIRVType *ResType,
116                          MachineInstr &I, Register SrcReg,
117                          unsigned Opcode) const;
118   bool selectUnOp(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
119                   unsigned Opcode) const;
120 
121   bool selectBitcast(Register ResVReg, const SPIRVType *ResType,
122                      MachineInstr &I) const;
123 
124   bool selectLoad(Register ResVReg, const SPIRVType *ResType,
125                   MachineInstr &I) const;
126   bool selectStore(MachineInstr &I) const;
127 
128   bool selectStackSave(Register ResVReg, const SPIRVType *ResType,
129                        MachineInstr &I) const;
130   bool selectStackRestore(MachineInstr &I) const;
131 
132   bool selectMemOperation(Register ResVReg, MachineInstr &I) const;
133 
134   bool selectAtomicRMW(Register ResVReg, const SPIRVType *ResType,
135                        MachineInstr &I, unsigned NewOpcode,
136                        unsigned NegateOpcode = 0) const;
137 
138   bool selectAtomicCmpXchg(Register ResVReg, const SPIRVType *ResType,
139                            MachineInstr &I) const;
140 
141   bool selectFence(MachineInstr &I) const;
142 
143   bool selectAddrSpaceCast(Register ResVReg, const SPIRVType *ResType,
144                            MachineInstr &I) const;
145 
146   bool selectAnyOrAll(Register ResVReg, const SPIRVType *ResType,
147                       MachineInstr &I, unsigned OpType) const;
148 
149   bool selectAll(Register ResVReg, const SPIRVType *ResType,
150                  MachineInstr &I) const;
151 
152   bool selectAny(Register ResVReg, const SPIRVType *ResType,
153                  MachineInstr &I) const;
154 
155   bool selectBitreverse(Register ResVReg, const SPIRVType *ResType,
156                         MachineInstr &I) const;
157 
158   bool selectBuildVector(Register ResVReg, const SPIRVType *ResType,
159                          MachineInstr &I) const;
160   bool selectSplatVector(Register ResVReg, const SPIRVType *ResType,
161                          MachineInstr &I) const;
162 
163   bool selectCmp(Register ResVReg, const SPIRVType *ResType,
164                  unsigned comparisonOpcode, MachineInstr &I) const;
165   bool selectCross(Register ResVReg, const SPIRVType *ResType,
166                    MachineInstr &I) const;
167   bool selectICmp(Register ResVReg, const SPIRVType *ResType,
168                   MachineInstr &I) const;
169   bool selectFCmp(Register ResVReg, const SPIRVType *ResType,
170                   MachineInstr &I) const;
171 
172   bool selectSign(Register ResVReg, const SPIRVType *ResType,
173                   MachineInstr &I) const;
174 
175   bool selectFloatDot(Register ResVReg, const SPIRVType *ResType,
176                       MachineInstr &I) const;
177 
178   bool selectOverflowArith(Register ResVReg, const SPIRVType *ResType,
179                            MachineInstr &I, unsigned Opcode) const;
180 
181   bool selectIntegerDot(Register ResVReg, const SPIRVType *ResType,
182                         MachineInstr &I) const;
183 
184   template <bool Signed>
185   bool selectDot4AddPacked(Register ResVReg, const SPIRVType *ResType,
186                            MachineInstr &I) const;
187   template <bool Signed>
188   bool selectDot4AddPackedExpansion(Register ResVReg, const SPIRVType *ResType,
189                                     MachineInstr &I) const;
190 
191   void renderImm32(MachineInstrBuilder &MIB, const MachineInstr &I,
192                    int OpIdx) const;
193   void renderFImm64(MachineInstrBuilder &MIB, const MachineInstr &I,
194                     int OpIdx) const;
195 
196   bool selectConst(Register ResVReg, const SPIRVType *ResType, const APInt &Imm,
197                    MachineInstr &I) const;
198 
199   bool selectSelect(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
200                     bool IsSigned) const;
201   bool selectIToF(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
202                   bool IsSigned, unsigned Opcode) const;
203   bool selectExt(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
204                  bool IsSigned) const;
205 
206   bool selectTrunc(Register ResVReg, const SPIRVType *ResType,
207                    MachineInstr &I) const;
208 
209   bool selectIntToBool(Register IntReg, Register ResVReg, MachineInstr &I,
210                        const SPIRVType *intTy, const SPIRVType *boolTy) const;
211 
212   bool selectOpUndef(Register ResVReg, const SPIRVType *ResType,
213                      MachineInstr &I) const;
214   bool selectFreeze(Register ResVReg, const SPIRVType *ResType,
215                     MachineInstr &I) const;
216   bool selectIntrinsic(Register ResVReg, const SPIRVType *ResType,
217                        MachineInstr &I) const;
218   bool selectExtractVal(Register ResVReg, const SPIRVType *ResType,
219                         MachineInstr &I) const;
220   bool selectInsertVal(Register ResVReg, const SPIRVType *ResType,
221                        MachineInstr &I) const;
222   bool selectExtractElt(Register ResVReg, const SPIRVType *ResType,
223                         MachineInstr &I) const;
224   bool selectInsertElt(Register ResVReg, const SPIRVType *ResType,
225                        MachineInstr &I) const;
226   bool selectGEP(Register ResVReg, const SPIRVType *ResType,
227                  MachineInstr &I) const;
228 
229   bool selectFrameIndex(Register ResVReg, const SPIRVType *ResType,
230                         MachineInstr &I) const;
231   bool selectAllocaArray(Register ResVReg, const SPIRVType *ResType,
232                          MachineInstr &I) const;
233 
234   bool selectBranch(MachineInstr &I) const;
235   bool selectBranchCond(MachineInstr &I) const;
236 
237   bool selectPhi(Register ResVReg, const SPIRVType *ResType,
238                  MachineInstr &I) const;
239 
240   bool selectExtInst(Register ResVReg, const SPIRVType *RestType,
241                      MachineInstr &I, GL::GLSLExtInst GLInst) const;
242   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
243                      MachineInstr &I, CL::OpenCLExtInst CLInst) const;
244   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
245                      MachineInstr &I, CL::OpenCLExtInst CLInst,
246                      GL::GLSLExtInst GLInst) const;
247   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
248                      MachineInstr &I, const ExtInstList &ExtInsts) const;
249 
250   bool selectLog10(Register ResVReg, const SPIRVType *ResType,
251                    MachineInstr &I) const;
252 
253   bool selectSaturate(Register ResVReg, const SPIRVType *ResType,
254                       MachineInstr &I) const;
255 
256   bool selectSpvThreadId(Register ResVReg, const SPIRVType *ResType,
257                          MachineInstr &I) const;
258 
259   bool selectWaveActiveCountBits(Register ResVReg, const SPIRVType *ResType,
260                                  MachineInstr &I) const;
261 
262   bool selectWaveReadLaneAt(Register ResVReg, const SPIRVType *ResType,
263                             MachineInstr &I) const;
264 
265   bool selectUnmergeValues(MachineInstr &I) const;
266 
267   bool selectHandleFromBinding(Register &ResVReg, const SPIRVType *ResType,
268                                MachineInstr &I) const;
269 
270   // Utilities
271   std::pair<Register, bool>
272   buildI32Constant(uint32_t Val, MachineInstr &I,
273                    const SPIRVType *ResType = nullptr) const;
274 
275   Register buildZerosVal(const SPIRVType *ResType, MachineInstr &I) const;
276   Register buildZerosValF(const SPIRVType *ResType, MachineInstr &I) const;
277   Register buildOnesVal(bool AllOnes, const SPIRVType *ResType,
278                         MachineInstr &I) const;
279   Register buildOnesValF(const SPIRVType *ResType, MachineInstr &I) const;
280 
281   bool wrapIntoSpecConstantOp(MachineInstr &I,
282                               SmallVector<Register> &CompositeArgs) const;
283 
284   Register getUcharPtrTypeReg(MachineInstr &I,
285                               SPIRV::StorageClass::StorageClass SC) const;
286   MachineInstrBuilder buildSpecConstantOp(MachineInstr &I, Register Dest,
287                                           Register Src, Register DestType,
288                                           uint32_t Opcode) const;
289   MachineInstrBuilder buildConstGenericPtr(MachineInstr &I, Register SrcPtr,
290                                            SPIRVType *SrcPtrTy) const;
291   Register buildPointerToResource(const SPIRVType *ResType, uint32_t Set,
292                                   uint32_t Binding, uint32_t ArraySize,
293                                   Register IndexReg, bool IsNonUniform,
294                                   MachineIRBuilder MIRBuilder) const;
295 };
296 
297 } // end anonymous namespace
298 
299 #define GET_GLOBALISEL_IMPL
300 #include "SPIRVGenGlobalISel.inc"
301 #undef GET_GLOBALISEL_IMPL
302 
303 SPIRVInstructionSelector::SPIRVInstructionSelector(const SPIRVTargetMachine &TM,
304                                                    const SPIRVSubtarget &ST,
305                                                    const RegisterBankInfo &RBI)
306     : InstructionSelector(), STI(ST), TII(*ST.getInstrInfo()),
307       TRI(*ST.getRegisterInfo()), RBI(RBI), GR(*ST.getSPIRVGlobalRegistry()),
308 #define GET_GLOBALISEL_PREDICATES_INIT
309 #include "SPIRVGenGlobalISel.inc"
310 #undef GET_GLOBALISEL_PREDICATES_INIT
311 #define GET_GLOBALISEL_TEMPORARIES_INIT
312 #include "SPIRVGenGlobalISel.inc"
313 #undef GET_GLOBALISEL_TEMPORARIES_INIT
314 {
315 }
316 
317 void SPIRVInstructionSelector::setupMF(MachineFunction &MF, GISelKnownBits *KB,
318                                        CodeGenCoverage *CoverageInfo,
319                                        ProfileSummaryInfo *PSI,
320                                        BlockFrequencyInfo *BFI) {
321   MRI = &MF.getRegInfo();
322   GR.setCurrentFunc(MF);
323   InstructionSelector::setupMF(MF, KB, CoverageInfo, PSI, BFI);
324 }
325 
326 // Ensure that register classes correspond to pattern matching rules.
327 void SPIRVInstructionSelector::resetVRegsType(MachineFunction &MF) {
328   if (HasVRegsReset == &MF)
329     return;
330   HasVRegsReset = &MF;
331 
332   MachineRegisterInfo &MRI = MF.getRegInfo();
333   for (unsigned I = 0, E = MRI.getNumVirtRegs(); I != E; ++I) {
334     Register Reg = Register::index2VirtReg(I);
335     LLT RegType = MRI.getType(Reg);
336     if (RegType.isScalar())
337       MRI.setType(Reg, LLT::scalar(64));
338     else if (RegType.isPointer())
339       MRI.setType(Reg, LLT::pointer(0, 64));
340     else if (RegType.isVector())
341       MRI.setType(Reg, LLT::fixed_vector(2, LLT::scalar(64)));
342   }
343   for (const auto &MBB : MF) {
344     for (const auto &MI : MBB) {
345       if (MI.getOpcode() != SPIRV::ASSIGN_TYPE)
346         continue;
347       Register DstReg = MI.getOperand(0).getReg();
348       LLT DstType = MRI.getType(DstReg);
349       Register SrcReg = MI.getOperand(1).getReg();
350       LLT SrcType = MRI.getType(SrcReg);
351       if (DstType != SrcType)
352         MRI.setType(DstReg, MRI.getType(SrcReg));
353 
354       const TargetRegisterClass *DstRC = MRI.getRegClassOrNull(DstReg);
355       const TargetRegisterClass *SrcRC = MRI.getRegClassOrNull(SrcReg);
356       if (DstRC != SrcRC && SrcRC)
357         MRI.setRegClass(DstReg, SrcRC);
358     }
359   }
360 }
361 
362 static bool isImm(const MachineOperand &MO, MachineRegisterInfo *MRI);
363 
364 // Defined in SPIRVLegalizerInfo.cpp.
365 extern bool isTypeFoldingSupported(unsigned Opcode);
366 
367 bool SPIRVInstructionSelector::select(MachineInstr &I) {
368   resetVRegsType(*I.getParent()->getParent());
369 
370   assert(I.getParent() && "Instruction should be in a basic block!");
371   assert(I.getParent()->getParent() && "Instruction should be in a function!");
372 
373   Register Opcode = I.getOpcode();
374   // If it's not a GMIR instruction, we've selected it already.
375   if (!isPreISelGenericOpcode(Opcode)) {
376     if (Opcode == SPIRV::ASSIGN_TYPE) { // These pseudos aren't needed any more.
377       Register DstReg = I.getOperand(0).getReg();
378       Register SrcReg = I.getOperand(1).getReg();
379       auto *Def = MRI->getVRegDef(SrcReg);
380       if (isTypeFoldingSupported(Def->getOpcode())) {
381         bool Res = selectImpl(I, *CoverageInfo);
382         LLVM_DEBUG({
383           if (!Res && Def->getOpcode() != TargetOpcode::G_CONSTANT) {
384             dbgs() << "Unexpected pattern in ASSIGN_TYPE.\nInstruction: ";
385             I.print(dbgs());
386           }
387         });
388         assert(Res || Def->getOpcode() == TargetOpcode::G_CONSTANT);
389         if (Res)
390           return Res;
391       }
392       MRI->setRegClass(SrcReg, MRI->getRegClass(DstReg));
393       MRI->replaceRegWith(SrcReg, DstReg);
394       I.removeFromParent();
395       return true;
396     } else if (I.getNumDefs() == 1) {
397       // Make all vregs 64 bits (for SPIR-V IDs).
398       MRI->setType(I.getOperand(0).getReg(), LLT::scalar(64));
399     }
400     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
401   }
402 
403   if (I.getNumOperands() != I.getNumExplicitOperands()) {
404     LLVM_DEBUG(errs() << "Generic instr has unexpected implicit operands\n");
405     return false;
406   }
407 
408   // Common code for getting return reg+type, and removing selected instr
409   // from parent occurs here. Instr-specific selection happens in spvSelect().
410   bool HasDefs = I.getNumDefs() > 0;
411   Register ResVReg = HasDefs ? I.getOperand(0).getReg() : Register(0);
412   SPIRVType *ResType = HasDefs ? GR.getSPIRVTypeForVReg(ResVReg) : nullptr;
413   assert(!HasDefs || ResType || I.getOpcode() == TargetOpcode::G_GLOBAL_VALUE);
414   if (spvSelect(ResVReg, ResType, I)) {
415     if (HasDefs) // Make all vregs 64 bits (for SPIR-V IDs).
416       for (unsigned i = 0; i < I.getNumDefs(); ++i)
417         MRI->setType(I.getOperand(i).getReg(), LLT::scalar(64));
418     I.removeFromParent();
419     return true;
420   }
421   return false;
422 }
423 
424 static bool mayApplyGenericSelection(unsigned Opcode) {
425   switch (Opcode) {
426   case TargetOpcode::G_CONSTANT:
427     return false;
428   case TargetOpcode::G_SADDO:
429   case TargetOpcode::G_SSUBO:
430     return true;
431   }
432   return isTypeFoldingSupported(Opcode);
433 }
434 
435 bool SPIRVInstructionSelector::spvSelect(Register ResVReg,
436                                          const SPIRVType *ResType,
437                                          MachineInstr &I) const {
438   const unsigned Opcode = I.getOpcode();
439   if (mayApplyGenericSelection(Opcode))
440     return selectImpl(I, *CoverageInfo);
441   switch (Opcode) {
442   case TargetOpcode::G_CONSTANT:
443     return selectConst(ResVReg, ResType, I.getOperand(1).getCImm()->getValue(),
444                        I);
445   case TargetOpcode::G_GLOBAL_VALUE:
446     return selectGlobalValue(ResVReg, I);
447   case TargetOpcode::G_IMPLICIT_DEF:
448     return selectOpUndef(ResVReg, ResType, I);
449   case TargetOpcode::G_FREEZE:
450     return selectFreeze(ResVReg, ResType, I);
451 
452   case TargetOpcode::G_INTRINSIC:
453   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
454   case TargetOpcode::G_INTRINSIC_CONVERGENT:
455   case TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS:
456     return selectIntrinsic(ResVReg, ResType, I);
457   case TargetOpcode::G_BITREVERSE:
458     return selectBitreverse(ResVReg, ResType, I);
459 
460   case TargetOpcode::G_BUILD_VECTOR:
461     return selectBuildVector(ResVReg, ResType, I);
462   case TargetOpcode::G_SPLAT_VECTOR:
463     return selectSplatVector(ResVReg, ResType, I);
464 
465   case TargetOpcode::G_SHUFFLE_VECTOR: {
466     MachineBasicBlock &BB = *I.getParent();
467     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorShuffle))
468                    .addDef(ResVReg)
469                    .addUse(GR.getSPIRVTypeID(ResType))
470                    .addUse(I.getOperand(1).getReg())
471                    .addUse(I.getOperand(2).getReg());
472     for (auto V : I.getOperand(3).getShuffleMask())
473       MIB.addImm(V);
474     return MIB.constrainAllUses(TII, TRI, RBI);
475   }
476   case TargetOpcode::G_MEMMOVE:
477   case TargetOpcode::G_MEMCPY:
478   case TargetOpcode::G_MEMSET:
479     return selectMemOperation(ResVReg, I);
480 
481   case TargetOpcode::G_ICMP:
482     return selectICmp(ResVReg, ResType, I);
483   case TargetOpcode::G_FCMP:
484     return selectFCmp(ResVReg, ResType, I);
485 
486   case TargetOpcode::G_FRAME_INDEX:
487     return selectFrameIndex(ResVReg, ResType, I);
488 
489   case TargetOpcode::G_LOAD:
490     return selectLoad(ResVReg, ResType, I);
491   case TargetOpcode::G_STORE:
492     return selectStore(I);
493 
494   case TargetOpcode::G_BR:
495     return selectBranch(I);
496   case TargetOpcode::G_BRCOND:
497     return selectBranchCond(I);
498 
499   case TargetOpcode::G_PHI:
500     return selectPhi(ResVReg, ResType, I);
501 
502   case TargetOpcode::G_FPTOSI:
503     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertFToS);
504   case TargetOpcode::G_FPTOUI:
505     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertFToU);
506 
507   case TargetOpcode::G_SITOFP:
508     return selectIToF(ResVReg, ResType, I, true, SPIRV::OpConvertSToF);
509   case TargetOpcode::G_UITOFP:
510     return selectIToF(ResVReg, ResType, I, false, SPIRV::OpConvertUToF);
511 
512   case TargetOpcode::G_CTPOP:
513     return selectUnOp(ResVReg, ResType, I, SPIRV::OpBitCount);
514   case TargetOpcode::G_SMIN:
515     return selectExtInst(ResVReg, ResType, I, CL::s_min, GL::SMin);
516   case TargetOpcode::G_UMIN:
517     return selectExtInst(ResVReg, ResType, I, CL::u_min, GL::UMin);
518 
519   case TargetOpcode::G_SMAX:
520     return selectExtInst(ResVReg, ResType, I, CL::s_max, GL::SMax);
521   case TargetOpcode::G_UMAX:
522     return selectExtInst(ResVReg, ResType, I, CL::u_max, GL::UMax);
523 
524   case TargetOpcode::G_FMA:
525     return selectExtInst(ResVReg, ResType, I, CL::fma, GL::Fma);
526 
527   case TargetOpcode::G_FPOW:
528     return selectExtInst(ResVReg, ResType, I, CL::pow, GL::Pow);
529   case TargetOpcode::G_FPOWI:
530     return selectExtInst(ResVReg, ResType, I, CL::pown);
531 
532   case TargetOpcode::G_FEXP:
533     return selectExtInst(ResVReg, ResType, I, CL::exp, GL::Exp);
534   case TargetOpcode::G_FEXP2:
535     return selectExtInst(ResVReg, ResType, I, CL::exp2, GL::Exp2);
536 
537   case TargetOpcode::G_FLOG:
538     return selectExtInst(ResVReg, ResType, I, CL::log, GL::Log);
539   case TargetOpcode::G_FLOG2:
540     return selectExtInst(ResVReg, ResType, I, CL::log2, GL::Log2);
541   case TargetOpcode::G_FLOG10:
542     return selectLog10(ResVReg, ResType, I);
543 
544   case TargetOpcode::G_FABS:
545     return selectExtInst(ResVReg, ResType, I, CL::fabs, GL::FAbs);
546   case TargetOpcode::G_ABS:
547     return selectExtInst(ResVReg, ResType, I, CL::s_abs, GL::SAbs);
548 
549   case TargetOpcode::G_FMINNUM:
550   case TargetOpcode::G_FMINIMUM:
551     return selectExtInst(ResVReg, ResType, I, CL::fmin, GL::NMin);
552   case TargetOpcode::G_FMAXNUM:
553   case TargetOpcode::G_FMAXIMUM:
554     return selectExtInst(ResVReg, ResType, I, CL::fmax, GL::NMax);
555 
556   case TargetOpcode::G_FCOPYSIGN:
557     return selectExtInst(ResVReg, ResType, I, CL::copysign);
558 
559   case TargetOpcode::G_FCEIL:
560     return selectExtInst(ResVReg, ResType, I, CL::ceil, GL::Ceil);
561   case TargetOpcode::G_FFLOOR:
562     return selectExtInst(ResVReg, ResType, I, CL::floor, GL::Floor);
563 
564   case TargetOpcode::G_FCOS:
565     return selectExtInst(ResVReg, ResType, I, CL::cos, GL::Cos);
566   case TargetOpcode::G_FSIN:
567     return selectExtInst(ResVReg, ResType, I, CL::sin, GL::Sin);
568   case TargetOpcode::G_FTAN:
569     return selectExtInst(ResVReg, ResType, I, CL::tan, GL::Tan);
570   case TargetOpcode::G_FACOS:
571     return selectExtInst(ResVReg, ResType, I, CL::acos, GL::Acos);
572   case TargetOpcode::G_FASIN:
573     return selectExtInst(ResVReg, ResType, I, CL::asin, GL::Asin);
574   case TargetOpcode::G_FATAN:
575     return selectExtInst(ResVReg, ResType, I, CL::atan, GL::Atan);
576   case TargetOpcode::G_FATAN2:
577     return selectExtInst(ResVReg, ResType, I, CL::atan2, GL::Atan2);
578   case TargetOpcode::G_FCOSH:
579     return selectExtInst(ResVReg, ResType, I, CL::cosh, GL::Cosh);
580   case TargetOpcode::G_FSINH:
581     return selectExtInst(ResVReg, ResType, I, CL::sinh, GL::Sinh);
582   case TargetOpcode::G_FTANH:
583     return selectExtInst(ResVReg, ResType, I, CL::tanh, GL::Tanh);
584 
585   case TargetOpcode::G_FSQRT:
586     return selectExtInst(ResVReg, ResType, I, CL::sqrt, GL::Sqrt);
587 
588   case TargetOpcode::G_CTTZ:
589   case TargetOpcode::G_CTTZ_ZERO_UNDEF:
590     return selectExtInst(ResVReg, ResType, I, CL::ctz);
591   case TargetOpcode::G_CTLZ:
592   case TargetOpcode::G_CTLZ_ZERO_UNDEF:
593     return selectExtInst(ResVReg, ResType, I, CL::clz);
594 
595   case TargetOpcode::G_INTRINSIC_ROUND:
596     return selectExtInst(ResVReg, ResType, I, CL::round, GL::Round);
597   case TargetOpcode::G_INTRINSIC_ROUNDEVEN:
598     return selectExtInst(ResVReg, ResType, I, CL::rint, GL::RoundEven);
599   case TargetOpcode::G_INTRINSIC_TRUNC:
600     return selectExtInst(ResVReg, ResType, I, CL::trunc, GL::Trunc);
601   case TargetOpcode::G_FRINT:
602   case TargetOpcode::G_FNEARBYINT:
603     return selectExtInst(ResVReg, ResType, I, CL::rint, GL::RoundEven);
604 
605   case TargetOpcode::G_SMULH:
606     return selectExtInst(ResVReg, ResType, I, CL::s_mul_hi);
607   case TargetOpcode::G_UMULH:
608     return selectExtInst(ResVReg, ResType, I, CL::u_mul_hi);
609 
610   case TargetOpcode::G_SADDSAT:
611     return selectExtInst(ResVReg, ResType, I, CL::s_add_sat);
612   case TargetOpcode::G_UADDSAT:
613     return selectExtInst(ResVReg, ResType, I, CL::u_add_sat);
614   case TargetOpcode::G_SSUBSAT:
615     return selectExtInst(ResVReg, ResType, I, CL::s_sub_sat);
616   case TargetOpcode::G_USUBSAT:
617     return selectExtInst(ResVReg, ResType, I, CL::u_sub_sat);
618 
619   case TargetOpcode::G_UADDO:
620     return selectOverflowArith(ResVReg, ResType, I,
621                                ResType->getOpcode() == SPIRV::OpTypeVector
622                                    ? SPIRV::OpIAddCarryV
623                                    : SPIRV::OpIAddCarryS);
624   case TargetOpcode::G_USUBO:
625     return selectOverflowArith(ResVReg, ResType, I,
626                                ResType->getOpcode() == SPIRV::OpTypeVector
627                                    ? SPIRV::OpISubBorrowV
628                                    : SPIRV::OpISubBorrowS);
629   case TargetOpcode::G_UMULO:
630     return selectOverflowArith(ResVReg, ResType, I, SPIRV::OpUMulExtended);
631   case TargetOpcode::G_SMULO:
632     return selectOverflowArith(ResVReg, ResType, I, SPIRV::OpSMulExtended);
633 
634   case TargetOpcode::G_SEXT:
635     return selectExt(ResVReg, ResType, I, true);
636   case TargetOpcode::G_ANYEXT:
637   case TargetOpcode::G_ZEXT:
638     return selectExt(ResVReg, ResType, I, false);
639   case TargetOpcode::G_TRUNC:
640     return selectTrunc(ResVReg, ResType, I);
641   case TargetOpcode::G_FPTRUNC:
642   case TargetOpcode::G_FPEXT:
643     return selectUnOp(ResVReg, ResType, I, SPIRV::OpFConvert);
644 
645   case TargetOpcode::G_PTRTOINT:
646     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertPtrToU);
647   case TargetOpcode::G_INTTOPTR:
648     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertUToPtr);
649   case TargetOpcode::G_BITCAST:
650     return selectBitcast(ResVReg, ResType, I);
651   case TargetOpcode::G_ADDRSPACE_CAST:
652     return selectAddrSpaceCast(ResVReg, ResType, I);
653   case TargetOpcode::G_PTR_ADD: {
654     // Currently, we get G_PTR_ADD only applied to global variables.
655     assert(I.getOperand(1).isReg() && I.getOperand(2).isReg());
656     Register GV = I.getOperand(1).getReg();
657     MachineRegisterInfo::def_instr_iterator II = MRI->def_instr_begin(GV);
658     (void)II;
659     assert(((*II).getOpcode() == TargetOpcode::G_GLOBAL_VALUE ||
660             (*II).getOpcode() == TargetOpcode::COPY ||
661             (*II).getOpcode() == SPIRV::OpVariable) &&
662            isImm(I.getOperand(2), MRI));
663     // It may be the initialization of a global variable.
664     bool IsGVInit = false;
665     for (MachineRegisterInfo::use_instr_iterator
666              UseIt = MRI->use_instr_begin(I.getOperand(0).getReg()),
667              UseEnd = MRI->use_instr_end();
668          UseIt != UseEnd; UseIt = std::next(UseIt)) {
669       if ((*UseIt).getOpcode() == TargetOpcode::G_GLOBAL_VALUE ||
670           (*UseIt).getOpcode() == SPIRV::OpVariable) {
671         IsGVInit = true;
672         break;
673       }
674     }
675     MachineBasicBlock &BB = *I.getParent();
676     if (!IsGVInit) {
677       SPIRVType *GVType = GR.getSPIRVTypeForVReg(GV);
678       SPIRVType *GVPointeeType = GR.getPointeeType(GVType);
679       SPIRVType *ResPointeeType = GR.getPointeeType(ResType);
680       if (GVPointeeType && ResPointeeType && GVPointeeType != ResPointeeType) {
681         // Build a new virtual register that is associated with the required
682         // data type.
683         Register NewVReg = MRI->createGenericVirtualRegister(MRI->getType(GV));
684         MRI->setRegClass(NewVReg, MRI->getRegClass(GV));
685         //  Having a correctly typed base we are ready to build the actually
686         //  required GEP. It may not be a constant though, because all Operands
687         //  of OpSpecConstantOp is to originate from other const instructions,
688         //  and only the AccessChain named opcodes accept a global OpVariable
689         //  instruction. We can't use an AccessChain opcode because of the type
690         //  mismatch between result and base types.
691         if (!GR.isBitcastCompatible(ResType, GVType))
692           report_fatal_error(
693               "incompatible result and operand types in a bitcast");
694         Register ResTypeReg = GR.getSPIRVTypeID(ResType);
695         MachineInstrBuilder MIB =
696             BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpBitcast))
697                 .addDef(NewVReg)
698                 .addUse(ResTypeReg)
699                 .addUse(GV);
700         return MIB.constrainAllUses(TII, TRI, RBI) &&
701                BuildMI(BB, I, I.getDebugLoc(),
702                        TII.get(STI.isVulkanEnv()
703                                    ? SPIRV::OpInBoundsAccessChain
704                                    : SPIRV::OpInBoundsPtrAccessChain))
705                    .addDef(ResVReg)
706                    .addUse(ResTypeReg)
707                    .addUse(NewVReg)
708                    .addUse(I.getOperand(2).getReg())
709                    .constrainAllUses(TII, TRI, RBI);
710       } else {
711         return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
712             .addDef(ResVReg)
713             .addUse(GR.getSPIRVTypeID(ResType))
714             .addImm(
715                 static_cast<uint32_t>(SPIRV::Opcode::InBoundsPtrAccessChain))
716             .addUse(GV)
717             .addUse(I.getOperand(2).getReg())
718             .constrainAllUses(TII, TRI, RBI);
719       }
720     }
721     // It's possible to translate G_PTR_ADD to OpSpecConstantOp: either to
722     // initialize a global variable with a constant expression (e.g., the test
723     // case opencl/basic/progvar_prog_scope_init.ll), or for another use case
724     Register Idx = buildZerosVal(GR.getOrCreateSPIRVIntegerType(32, I, TII), I);
725     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
726                    .addDef(ResVReg)
727                    .addUse(GR.getSPIRVTypeID(ResType))
728                    .addImm(static_cast<uint32_t>(
729                        SPIRV::Opcode::InBoundsPtrAccessChain))
730                    .addUse(GV)
731                    .addUse(Idx)
732                    .addUse(I.getOperand(2).getReg());
733     return MIB.constrainAllUses(TII, TRI, RBI);
734   }
735 
736   case TargetOpcode::G_ATOMICRMW_OR:
737     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicOr);
738   case TargetOpcode::G_ATOMICRMW_ADD:
739     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicIAdd);
740   case TargetOpcode::G_ATOMICRMW_AND:
741     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicAnd);
742   case TargetOpcode::G_ATOMICRMW_MAX:
743     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicSMax);
744   case TargetOpcode::G_ATOMICRMW_MIN:
745     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicSMin);
746   case TargetOpcode::G_ATOMICRMW_SUB:
747     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicISub);
748   case TargetOpcode::G_ATOMICRMW_XOR:
749     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicXor);
750   case TargetOpcode::G_ATOMICRMW_UMAX:
751     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicUMax);
752   case TargetOpcode::G_ATOMICRMW_UMIN:
753     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicUMin);
754   case TargetOpcode::G_ATOMICRMW_XCHG:
755     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicExchange);
756   case TargetOpcode::G_ATOMIC_CMPXCHG:
757     return selectAtomicCmpXchg(ResVReg, ResType, I);
758 
759   case TargetOpcode::G_ATOMICRMW_FADD:
760     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFAddEXT);
761   case TargetOpcode::G_ATOMICRMW_FSUB:
762     // Translate G_ATOMICRMW_FSUB to OpAtomicFAddEXT with negative value operand
763     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFAddEXT,
764                            SPIRV::OpFNegate);
765   case TargetOpcode::G_ATOMICRMW_FMIN:
766     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFMinEXT);
767   case TargetOpcode::G_ATOMICRMW_FMAX:
768     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFMaxEXT);
769 
770   case TargetOpcode::G_FENCE:
771     return selectFence(I);
772 
773   case TargetOpcode::G_STACKSAVE:
774     return selectStackSave(ResVReg, ResType, I);
775   case TargetOpcode::G_STACKRESTORE:
776     return selectStackRestore(I);
777 
778   case TargetOpcode::G_UNMERGE_VALUES:
779     return selectUnmergeValues(I);
780 
781   // Discard gen opcodes for intrinsics which we do not expect to actually
782   // represent code after lowering or intrinsics which are not implemented but
783   // should not crash when found in a customer's LLVM IR input.
784   case TargetOpcode::G_TRAP:
785   case TargetOpcode::G_DEBUGTRAP:
786   case TargetOpcode::G_UBSANTRAP:
787   case TargetOpcode::DBG_LABEL:
788     return true;
789 
790   default:
791     return false;
792   }
793 }
794 
795 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
796                                              const SPIRVType *ResType,
797                                              MachineInstr &I,
798                                              GL::GLSLExtInst GLInst) const {
799   return selectExtInst(ResVReg, ResType, I,
800                        {{SPIRV::InstructionSet::GLSL_std_450, GLInst}});
801 }
802 
803 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
804                                              const SPIRVType *ResType,
805                                              MachineInstr &I,
806                                              CL::OpenCLExtInst CLInst) const {
807   return selectExtInst(ResVReg, ResType, I,
808                        {{SPIRV::InstructionSet::OpenCL_std, CLInst}});
809 }
810 
811 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
812                                              const SPIRVType *ResType,
813                                              MachineInstr &I,
814                                              CL::OpenCLExtInst CLInst,
815                                              GL::GLSLExtInst GLInst) const {
816   ExtInstList ExtInsts = {{SPIRV::InstructionSet::OpenCL_std, CLInst},
817                           {SPIRV::InstructionSet::GLSL_std_450, GLInst}};
818   return selectExtInst(ResVReg, ResType, I, ExtInsts);
819 }
820 
821 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
822                                              const SPIRVType *ResType,
823                                              MachineInstr &I,
824                                              const ExtInstList &Insts) const {
825 
826   for (const auto &Ex : Insts) {
827     SPIRV::InstructionSet::InstructionSet Set = Ex.first;
828     uint32_t Opcode = Ex.second;
829     if (STI.canUseExtInstSet(Set)) {
830       MachineBasicBlock &BB = *I.getParent();
831       auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
832                      .addDef(ResVReg)
833                      .addUse(GR.getSPIRVTypeID(ResType))
834                      .addImm(static_cast<uint32_t>(Set))
835                      .addImm(Opcode);
836       const unsigned NumOps = I.getNumOperands();
837       unsigned Index = 1;
838       if (Index < NumOps &&
839           I.getOperand(Index).getType() ==
840               MachineOperand::MachineOperandType::MO_IntrinsicID)
841         Index = 2;
842       for (; Index < NumOps; ++Index)
843         MIB.add(I.getOperand(Index));
844       return MIB.constrainAllUses(TII, TRI, RBI);
845     }
846   }
847   return false;
848 }
849 
850 bool SPIRVInstructionSelector::selectNAryOpWithSrcs(Register ResVReg,
851                                                     const SPIRVType *ResType,
852                                                     MachineInstr &I,
853                                                     std::vector<Register> Srcs,
854                                                     unsigned Opcode) const {
855   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
856                  .addDef(ResVReg)
857                  .addUse(GR.getSPIRVTypeID(ResType));
858   for (Register SReg : Srcs) {
859     MIB.addUse(SReg);
860   }
861   return MIB.constrainAllUses(TII, TRI, RBI);
862 }
863 
864 bool SPIRVInstructionSelector::selectUnOpWithSrc(Register ResVReg,
865                                                  const SPIRVType *ResType,
866                                                  MachineInstr &I,
867                                                  Register SrcReg,
868                                                  unsigned Opcode) const {
869   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
870       .addDef(ResVReg)
871       .addUse(GR.getSPIRVTypeID(ResType))
872       .addUse(SrcReg)
873       .constrainAllUses(TII, TRI, RBI);
874 }
875 
876 bool SPIRVInstructionSelector::selectUnOp(Register ResVReg,
877                                           const SPIRVType *ResType,
878                                           MachineInstr &I,
879                                           unsigned Opcode) const {
880   if (STI.isOpenCLEnv() && I.getOperand(1).isReg()) {
881     Register SrcReg = I.getOperand(1).getReg();
882     bool IsGV = false;
883     for (MachineRegisterInfo::def_instr_iterator DefIt =
884              MRI->def_instr_begin(SrcReg);
885          DefIt != MRI->def_instr_end(); DefIt = std::next(DefIt)) {
886       if ((*DefIt).getOpcode() == TargetOpcode::G_GLOBAL_VALUE) {
887         IsGV = true;
888         break;
889       }
890     }
891     if (IsGV) {
892       uint32_t SpecOpcode = 0;
893       switch (Opcode) {
894       case SPIRV::OpConvertPtrToU:
895         SpecOpcode = static_cast<uint32_t>(SPIRV::Opcode::ConvertPtrToU);
896         break;
897       case SPIRV::OpConvertUToPtr:
898         SpecOpcode = static_cast<uint32_t>(SPIRV::Opcode::ConvertUToPtr);
899         break;
900       }
901       if (SpecOpcode)
902         return BuildMI(*I.getParent(), I, I.getDebugLoc(),
903                        TII.get(SPIRV::OpSpecConstantOp))
904             .addDef(ResVReg)
905             .addUse(GR.getSPIRVTypeID(ResType))
906             .addImm(SpecOpcode)
907             .addUse(SrcReg)
908             .constrainAllUses(TII, TRI, RBI);
909     }
910   }
911   return selectUnOpWithSrc(ResVReg, ResType, I, I.getOperand(1).getReg(),
912                            Opcode);
913 }
914 
915 bool SPIRVInstructionSelector::selectBitcast(Register ResVReg,
916                                              const SPIRVType *ResType,
917                                              MachineInstr &I) const {
918   Register OpReg = I.getOperand(1).getReg();
919   SPIRVType *OpType = OpReg.isValid() ? GR.getSPIRVTypeForVReg(OpReg) : nullptr;
920   if (!GR.isBitcastCompatible(ResType, OpType))
921     report_fatal_error("incompatible result and operand types in a bitcast");
922   return selectUnOp(ResVReg, ResType, I, SPIRV::OpBitcast);
923 }
924 
925 static void addMemoryOperands(MachineMemOperand *MemOp,
926                               MachineInstrBuilder &MIB) {
927   uint32_t SpvMemOp = static_cast<uint32_t>(SPIRV::MemoryOperand::None);
928   if (MemOp->isVolatile())
929     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Volatile);
930   if (MemOp->isNonTemporal())
931     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Nontemporal);
932   if (MemOp->getAlign().value())
933     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Aligned);
934 
935   if (SpvMemOp != static_cast<uint32_t>(SPIRV::MemoryOperand::None)) {
936     MIB.addImm(SpvMemOp);
937     if (SpvMemOp & static_cast<uint32_t>(SPIRV::MemoryOperand::Aligned))
938       MIB.addImm(MemOp->getAlign().value());
939   }
940 }
941 
942 static void addMemoryOperands(uint64_t Flags, MachineInstrBuilder &MIB) {
943   uint32_t SpvMemOp = static_cast<uint32_t>(SPIRV::MemoryOperand::None);
944   if (Flags & MachineMemOperand::Flags::MOVolatile)
945     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Volatile);
946   if (Flags & MachineMemOperand::Flags::MONonTemporal)
947     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Nontemporal);
948 
949   if (SpvMemOp != static_cast<uint32_t>(SPIRV::MemoryOperand::None))
950     MIB.addImm(SpvMemOp);
951 }
952 
953 bool SPIRVInstructionSelector::selectLoad(Register ResVReg,
954                                           const SPIRVType *ResType,
955                                           MachineInstr &I) const {
956   unsigned OpOffset = isa<GIntrinsic>(I) ? 1 : 0;
957   Register Ptr = I.getOperand(1 + OpOffset).getReg();
958   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
959                  .addDef(ResVReg)
960                  .addUse(GR.getSPIRVTypeID(ResType))
961                  .addUse(Ptr);
962   if (!I.getNumMemOperands()) {
963     assert(I.getOpcode() == TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS ||
964            I.getOpcode() ==
965                TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS);
966     addMemoryOperands(I.getOperand(2 + OpOffset).getImm(), MIB);
967   } else {
968     addMemoryOperands(*I.memoperands_begin(), MIB);
969   }
970   return MIB.constrainAllUses(TII, TRI, RBI);
971 }
972 
973 bool SPIRVInstructionSelector::selectStore(MachineInstr &I) const {
974   unsigned OpOffset = isa<GIntrinsic>(I) ? 1 : 0;
975   Register StoreVal = I.getOperand(0 + OpOffset).getReg();
976   Register Ptr = I.getOperand(1 + OpOffset).getReg();
977   MachineBasicBlock &BB = *I.getParent();
978   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpStore))
979                  .addUse(Ptr)
980                  .addUse(StoreVal);
981   if (!I.getNumMemOperands()) {
982     assert(I.getOpcode() == TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS ||
983            I.getOpcode() ==
984                TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS);
985     addMemoryOperands(I.getOperand(2 + OpOffset).getImm(), MIB);
986   } else {
987     addMemoryOperands(*I.memoperands_begin(), MIB);
988   }
989   return MIB.constrainAllUses(TII, TRI, RBI);
990 }
991 
992 bool SPIRVInstructionSelector::selectStackSave(Register ResVReg,
993                                                const SPIRVType *ResType,
994                                                MachineInstr &I) const {
995   if (!STI.canUseExtension(SPIRV::Extension::SPV_INTEL_variable_length_array))
996     report_fatal_error(
997         "llvm.stacksave intrinsic: this instruction requires the following "
998         "SPIR-V extension: SPV_INTEL_variable_length_array",
999         false);
1000   MachineBasicBlock &BB = *I.getParent();
1001   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSaveMemoryINTEL))
1002       .addDef(ResVReg)
1003       .addUse(GR.getSPIRVTypeID(ResType))
1004       .constrainAllUses(TII, TRI, RBI);
1005 }
1006 
1007 bool SPIRVInstructionSelector::selectStackRestore(MachineInstr &I) const {
1008   if (!STI.canUseExtension(SPIRV::Extension::SPV_INTEL_variable_length_array))
1009     report_fatal_error(
1010         "llvm.stackrestore intrinsic: this instruction requires the following "
1011         "SPIR-V extension: SPV_INTEL_variable_length_array",
1012         false);
1013   if (!I.getOperand(0).isReg())
1014     return false;
1015   MachineBasicBlock &BB = *I.getParent();
1016   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpRestoreMemoryINTEL))
1017       .addUse(I.getOperand(0).getReg())
1018       .constrainAllUses(TII, TRI, RBI);
1019 }
1020 
1021 bool SPIRVInstructionSelector::selectMemOperation(Register ResVReg,
1022                                                   MachineInstr &I) const {
1023   MachineBasicBlock &BB = *I.getParent();
1024   Register SrcReg = I.getOperand(1).getReg();
1025   bool Result = true;
1026   if (I.getOpcode() == TargetOpcode::G_MEMSET) {
1027     assert(I.getOperand(1).isReg() && I.getOperand(2).isReg());
1028     unsigned Val = getIConstVal(I.getOperand(1).getReg(), MRI);
1029     unsigned Num = getIConstVal(I.getOperand(2).getReg(), MRI);
1030     SPIRVType *ValTy = GR.getOrCreateSPIRVIntegerType(8, I, TII);
1031     SPIRVType *ArrTy = GR.getOrCreateSPIRVArrayType(ValTy, Num, I, TII);
1032     Register Const = GR.getOrCreateConstIntArray(Val, Num, I, ArrTy, TII);
1033     SPIRVType *VarTy = GR.getOrCreateSPIRVPointerType(
1034         ArrTy, I, TII, SPIRV::StorageClass::UniformConstant);
1035     // TODO: check if we have such GV, add init, use buildGlobalVariable.
1036     Function &CurFunction = GR.CurMF->getFunction();
1037     Type *LLVMArrTy =
1038         ArrayType::get(IntegerType::get(CurFunction.getContext(), 8), Num);
1039     // Module takes ownership of the global var.
1040     GlobalVariable *GV = new GlobalVariable(*CurFunction.getParent(), LLVMArrTy,
1041                                             true, GlobalValue::InternalLinkage,
1042                                             Constant::getNullValue(LLVMArrTy));
1043     Register VarReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1044     GR.add(GV, GR.CurMF, VarReg);
1045 
1046     Result &=
1047         BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpVariable))
1048             .addDef(VarReg)
1049             .addUse(GR.getSPIRVTypeID(VarTy))
1050             .addImm(SPIRV::StorageClass::UniformConstant)
1051             .addUse(Const)
1052             .constrainAllUses(TII, TRI, RBI);
1053     buildOpDecorate(VarReg, I, TII, SPIRV::Decoration::Constant, {});
1054     SPIRVType *SourceTy = GR.getOrCreateSPIRVPointerType(
1055         ValTy, I, TII, SPIRV::StorageClass::UniformConstant);
1056     SrcReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1057     selectUnOpWithSrc(SrcReg, SourceTy, I, VarReg, SPIRV::OpBitcast);
1058   }
1059   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCopyMemorySized))
1060                  .addUse(I.getOperand(0).getReg())
1061                  .addUse(SrcReg)
1062                  .addUse(I.getOperand(2).getReg());
1063   if (I.getNumMemOperands())
1064     addMemoryOperands(*I.memoperands_begin(), MIB);
1065   Result &= MIB.constrainAllUses(TII, TRI, RBI);
1066   if (ResVReg.isValid() && ResVReg != MIB->getOperand(0).getReg())
1067     Result &=
1068         BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY), ResVReg)
1069             .addUse(MIB->getOperand(0).getReg())
1070             .constrainAllUses(TII, TRI, RBI);
1071   return Result;
1072 }
1073 
1074 bool SPIRVInstructionSelector::selectAtomicRMW(Register ResVReg,
1075                                                const SPIRVType *ResType,
1076                                                MachineInstr &I,
1077                                                unsigned NewOpcode,
1078                                                unsigned NegateOpcode) const {
1079   bool Result = true;
1080   assert(I.hasOneMemOperand());
1081   const MachineMemOperand *MemOp = *I.memoperands_begin();
1082   uint32_t Scope = static_cast<uint32_t>(getMemScope(
1083       GR.CurMF->getFunction().getContext(), MemOp->getSyncScopeID()));
1084   auto ScopeConstant = buildI32Constant(Scope, I);
1085   Register ScopeReg = ScopeConstant.first;
1086   Result &= ScopeConstant.second;
1087 
1088   Register Ptr = I.getOperand(1).getReg();
1089   // TODO: Changed as it's implemented in the translator. See test/atomicrmw.ll
1090   // auto ScSem =
1091   // getMemSemanticsForStorageClass(GR.getPointerStorageClass(Ptr));
1092   AtomicOrdering AO = MemOp->getSuccessOrdering();
1093   uint32_t MemSem = static_cast<uint32_t>(getMemSemantics(AO));
1094   auto MemSemConstant = buildI32Constant(MemSem /*| ScSem*/, I);
1095   Register MemSemReg = MemSemConstant.first;
1096   Result &= MemSemConstant.second;
1097 
1098   Register ValueReg = I.getOperand(2).getReg();
1099   if (NegateOpcode != 0) {
1100     // Translation with negative value operand is requested
1101     Register TmpReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1102     Result &= selectUnOpWithSrc(TmpReg, ResType, I, ValueReg, NegateOpcode);
1103     ValueReg = TmpReg;
1104   }
1105 
1106   return Result &&
1107          BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(NewOpcode))
1108              .addDef(ResVReg)
1109              .addUse(GR.getSPIRVTypeID(ResType))
1110              .addUse(Ptr)
1111              .addUse(ScopeReg)
1112              .addUse(MemSemReg)
1113              .addUse(ValueReg)
1114              .constrainAllUses(TII, TRI, RBI);
1115 }
1116 
1117 bool SPIRVInstructionSelector::selectUnmergeValues(MachineInstr &I) const {
1118   unsigned ArgI = I.getNumOperands() - 1;
1119   Register SrcReg =
1120       I.getOperand(ArgI).isReg() ? I.getOperand(ArgI).getReg() : Register(0);
1121   SPIRVType *DefType =
1122       SrcReg.isValid() ? GR.getSPIRVTypeForVReg(SrcReg) : nullptr;
1123   if (!DefType || DefType->getOpcode() != SPIRV::OpTypeVector)
1124     report_fatal_error(
1125         "cannot select G_UNMERGE_VALUES with a non-vector argument");
1126 
1127   SPIRVType *ScalarType =
1128       GR.getSPIRVTypeForVReg(DefType->getOperand(1).getReg());
1129   MachineBasicBlock &BB = *I.getParent();
1130   bool Res = false;
1131   for (unsigned i = 0; i < I.getNumDefs(); ++i) {
1132     Register ResVReg = I.getOperand(i).getReg();
1133     SPIRVType *ResType = GR.getSPIRVTypeForVReg(ResVReg);
1134     if (!ResType) {
1135       // There was no "assign type" actions, let's fix this now
1136       ResType = ScalarType;
1137       MRI->setRegClass(ResVReg, GR.getRegClass(ResType));
1138       MRI->setType(ResVReg, LLT::scalar(GR.getScalarOrVectorBitWidth(ResType)));
1139       GR.assignSPIRVTypeToVReg(ResType, ResVReg, *GR.CurMF);
1140     }
1141     auto MIB =
1142         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1143             .addDef(ResVReg)
1144             .addUse(GR.getSPIRVTypeID(ResType))
1145             .addUse(SrcReg)
1146             .addImm(static_cast<int64_t>(i));
1147     Res |= MIB.constrainAllUses(TII, TRI, RBI);
1148   }
1149   return Res;
1150 }
1151 
1152 bool SPIRVInstructionSelector::selectFence(MachineInstr &I) const {
1153   AtomicOrdering AO = AtomicOrdering(I.getOperand(0).getImm());
1154   uint32_t MemSem = static_cast<uint32_t>(getMemSemantics(AO));
1155   auto MemSemConstant = buildI32Constant(MemSem, I);
1156   Register MemSemReg = MemSemConstant.first;
1157   bool Result = MemSemConstant.second;
1158   SyncScope::ID Ord = SyncScope::ID(I.getOperand(1).getImm());
1159   uint32_t Scope = static_cast<uint32_t>(
1160       getMemScope(GR.CurMF->getFunction().getContext(), Ord));
1161   auto ScopeConstant = buildI32Constant(Scope, I);
1162   Register ScopeReg = ScopeConstant.first;
1163   Result &= ScopeConstant.second;
1164   MachineBasicBlock &BB = *I.getParent();
1165   return Result &&
1166          BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpMemoryBarrier))
1167              .addUse(ScopeReg)
1168              .addUse(MemSemReg)
1169              .constrainAllUses(TII, TRI, RBI);
1170 }
1171 
1172 bool SPIRVInstructionSelector::selectOverflowArith(Register ResVReg,
1173                                                    const SPIRVType *ResType,
1174                                                    MachineInstr &I,
1175                                                    unsigned Opcode) const {
1176   Type *ResTy = nullptr;
1177   StringRef ResName;
1178   if (!GR.findValueAttrs(&I, ResTy, ResName))
1179     report_fatal_error(
1180         "Not enough info to select the arithmetic with overflow instruction");
1181   if (!ResTy || !ResTy->isStructTy())
1182     report_fatal_error("Expect struct type result for the arithmetic "
1183                        "with overflow instruction");
1184   // "Result Type must be from OpTypeStruct. The struct must have two members,
1185   // and the two members must be the same type."
1186   Type *ResElemTy = cast<StructType>(ResTy)->getElementType(0);
1187   ResTy = StructType::create(SmallVector<Type *, 2>{ResElemTy, ResElemTy});
1188   // Build SPIR-V types and constant(s) if needed.
1189   MachineIRBuilder MIRBuilder(I);
1190   SPIRVType *StructType = GR.getOrCreateSPIRVType(
1191       ResTy, MIRBuilder, SPIRV::AccessQualifier::ReadWrite, false);
1192   assert(I.getNumDefs() > 1 && "Not enought operands");
1193   SPIRVType *BoolType = GR.getOrCreateSPIRVBoolType(I, TII);
1194   unsigned N = GR.getScalarOrVectorComponentCount(ResType);
1195   if (N > 1)
1196     BoolType = GR.getOrCreateSPIRVVectorType(BoolType, N, I, TII);
1197   Register BoolTypeReg = GR.getSPIRVTypeID(BoolType);
1198   Register ZeroReg = buildZerosVal(ResType, I);
1199   // A new virtual register to store the result struct.
1200   Register StructVReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1201   MRI->setRegClass(StructVReg, &SPIRV::IDRegClass);
1202   // Build the result name if needed.
1203   if (ResName.size() > 0)
1204     buildOpName(StructVReg, ResName, MIRBuilder);
1205   // Build the arithmetic with overflow instruction.
1206   MachineBasicBlock &BB = *I.getParent();
1207   auto MIB =
1208       BuildMI(BB, MIRBuilder.getInsertPt(), I.getDebugLoc(), TII.get(Opcode))
1209           .addDef(StructVReg)
1210           .addUse(GR.getSPIRVTypeID(StructType));
1211   for (unsigned i = I.getNumDefs(); i < I.getNumOperands(); ++i)
1212     MIB.addUse(I.getOperand(i).getReg());
1213   bool Result = MIB.constrainAllUses(TII, TRI, RBI);
1214   // Build instructions to extract fields of the instruction's result.
1215   // A new virtual register to store the higher part of the result struct.
1216   Register HigherVReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1217   MRI->setRegClass(HigherVReg, &SPIRV::iIDRegClass);
1218   for (unsigned i = 0; i < I.getNumDefs(); ++i) {
1219     auto MIB =
1220         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1221             .addDef(i == 1 ? HigherVReg : I.getOperand(i).getReg())
1222             .addUse(GR.getSPIRVTypeID(ResType))
1223             .addUse(StructVReg)
1224             .addImm(i);
1225     Result &= MIB.constrainAllUses(TII, TRI, RBI);
1226   }
1227   // Build boolean value from the higher part.
1228   return Result && BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpINotEqual))
1229                        .addDef(I.getOperand(1).getReg())
1230                        .addUse(BoolTypeReg)
1231                        .addUse(HigherVReg)
1232                        .addUse(ZeroReg)
1233                        .constrainAllUses(TII, TRI, RBI);
1234 }
1235 
1236 bool SPIRVInstructionSelector::selectAtomicCmpXchg(Register ResVReg,
1237                                                    const SPIRVType *ResType,
1238                                                    MachineInstr &I) const {
1239   bool Result = true;
1240   Register ScopeReg;
1241   Register MemSemEqReg;
1242   Register MemSemNeqReg;
1243   Register Ptr = I.getOperand(2).getReg();
1244   if (!isa<GIntrinsic>(I)) {
1245     assert(I.hasOneMemOperand());
1246     const MachineMemOperand *MemOp = *I.memoperands_begin();
1247     unsigned Scope = static_cast<uint32_t>(getMemScope(
1248         GR.CurMF->getFunction().getContext(), MemOp->getSyncScopeID()));
1249     auto ScopeConstant = buildI32Constant(Scope, I);
1250     ScopeReg = ScopeConstant.first;
1251     Result &= ScopeConstant.second;
1252 
1253     unsigned ScSem = static_cast<uint32_t>(
1254         getMemSemanticsForStorageClass(GR.getPointerStorageClass(Ptr)));
1255     AtomicOrdering AO = MemOp->getSuccessOrdering();
1256     unsigned MemSemEq = static_cast<uint32_t>(getMemSemantics(AO)) | ScSem;
1257     auto MemSemEqConstant = buildI32Constant(MemSemEq, I);
1258     MemSemEqReg = MemSemEqConstant.first;
1259     Result &= MemSemEqConstant.second;
1260     AtomicOrdering FO = MemOp->getFailureOrdering();
1261     unsigned MemSemNeq = static_cast<uint32_t>(getMemSemantics(FO)) | ScSem;
1262     if (MemSemEq == MemSemNeq)
1263       MemSemNeqReg = MemSemEqReg;
1264     else {
1265       auto MemSemNeqConstant = buildI32Constant(MemSemEq, I);
1266       MemSemNeqReg = MemSemNeqConstant.first;
1267       Result &= MemSemNeqConstant.second;
1268     }
1269   } else {
1270     ScopeReg = I.getOperand(5).getReg();
1271     MemSemEqReg = I.getOperand(6).getReg();
1272     MemSemNeqReg = I.getOperand(7).getReg();
1273   }
1274 
1275   Register Cmp = I.getOperand(3).getReg();
1276   Register Val = I.getOperand(4).getReg();
1277   SPIRVType *SpvValTy = GR.getSPIRVTypeForVReg(Val);
1278   Register ACmpRes = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1279   const DebugLoc &DL = I.getDebugLoc();
1280   Result &=
1281       BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpAtomicCompareExchange))
1282           .addDef(ACmpRes)
1283           .addUse(GR.getSPIRVTypeID(SpvValTy))
1284           .addUse(Ptr)
1285           .addUse(ScopeReg)
1286           .addUse(MemSemEqReg)
1287           .addUse(MemSemNeqReg)
1288           .addUse(Val)
1289           .addUse(Cmp)
1290           .constrainAllUses(TII, TRI, RBI);
1291   Register CmpSuccReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1292   SPIRVType *BoolTy = GR.getOrCreateSPIRVBoolType(I, TII);
1293   Result &= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpIEqual))
1294                 .addDef(CmpSuccReg)
1295                 .addUse(GR.getSPIRVTypeID(BoolTy))
1296                 .addUse(ACmpRes)
1297                 .addUse(Cmp)
1298                 .constrainAllUses(TII, TRI, RBI);
1299   Register TmpReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1300   Result &= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpCompositeInsert))
1301                 .addDef(TmpReg)
1302                 .addUse(GR.getSPIRVTypeID(ResType))
1303                 .addUse(ACmpRes)
1304                 .addUse(GR.getOrCreateUndef(I, ResType, TII))
1305                 .addImm(0)
1306                 .constrainAllUses(TII, TRI, RBI);
1307   return Result &&
1308          BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpCompositeInsert))
1309              .addDef(ResVReg)
1310              .addUse(GR.getSPIRVTypeID(ResType))
1311              .addUse(CmpSuccReg)
1312              .addUse(TmpReg)
1313              .addImm(1)
1314              .constrainAllUses(TII, TRI, RBI);
1315 }
1316 
1317 static bool isGenericCastablePtr(SPIRV::StorageClass::StorageClass SC) {
1318   switch (SC) {
1319   case SPIRV::StorageClass::Workgroup:
1320   case SPIRV::StorageClass::CrossWorkgroup:
1321   case SPIRV::StorageClass::Function:
1322     return true;
1323   default:
1324     return false;
1325   }
1326 }
1327 
1328 static bool isUSMStorageClass(SPIRV::StorageClass::StorageClass SC) {
1329   switch (SC) {
1330   case SPIRV::StorageClass::DeviceOnlyINTEL:
1331   case SPIRV::StorageClass::HostOnlyINTEL:
1332     return true;
1333   default:
1334     return false;
1335   }
1336 }
1337 
1338 // Returns true ResVReg is referred only from global vars and OpName's.
1339 static bool isASCastInGVar(MachineRegisterInfo *MRI, Register ResVReg) {
1340   bool IsGRef = false;
1341   bool IsAllowedRefs =
1342       std::all_of(MRI->use_instr_begin(ResVReg), MRI->use_instr_end(),
1343                   [&IsGRef](auto const &It) {
1344                     unsigned Opcode = It.getOpcode();
1345                     if (Opcode == SPIRV::OpConstantComposite ||
1346                         Opcode == SPIRV::OpVariable ||
1347                         isSpvIntrinsic(It, Intrinsic::spv_init_global))
1348                       return IsGRef = true;
1349                     return Opcode == SPIRV::OpName;
1350                   });
1351   return IsAllowedRefs && IsGRef;
1352 }
1353 
1354 Register SPIRVInstructionSelector::getUcharPtrTypeReg(
1355     MachineInstr &I, SPIRV::StorageClass::StorageClass SC) const {
1356   return GR.getSPIRVTypeID(GR.getOrCreateSPIRVPointerType(
1357       GR.getOrCreateSPIRVIntegerType(8, I, TII), I, TII, SC));
1358 }
1359 
1360 MachineInstrBuilder
1361 SPIRVInstructionSelector::buildSpecConstantOp(MachineInstr &I, Register Dest,
1362                                               Register Src, Register DestType,
1363                                               uint32_t Opcode) const {
1364   return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1365                  TII.get(SPIRV::OpSpecConstantOp))
1366       .addDef(Dest)
1367       .addUse(DestType)
1368       .addImm(Opcode)
1369       .addUse(Src);
1370 }
1371 
1372 MachineInstrBuilder
1373 SPIRVInstructionSelector::buildConstGenericPtr(MachineInstr &I, Register SrcPtr,
1374                                                SPIRVType *SrcPtrTy) const {
1375   SPIRVType *GenericPtrTy = GR.getOrCreateSPIRVPointerType(
1376       GR.getPointeeType(SrcPtrTy), I, TII, SPIRV::StorageClass::Generic);
1377   Register Tmp = MRI->createVirtualRegister(&SPIRV::pIDRegClass);
1378   MRI->setType(Tmp, LLT::pointer(storageClassToAddressSpace(
1379                                      SPIRV::StorageClass::Generic),
1380                                  GR.getPointerSize()));
1381   MachineFunction *MF = I.getParent()->getParent();
1382   GR.assignSPIRVTypeToVReg(GenericPtrTy, Tmp, *MF);
1383   MachineInstrBuilder MIB = buildSpecConstantOp(
1384       I, Tmp, SrcPtr, GR.getSPIRVTypeID(GenericPtrTy),
1385       static_cast<uint32_t>(SPIRV::Opcode::PtrCastToGeneric));
1386   GR.add(MIB.getInstr(), MF, Tmp);
1387   return MIB;
1388 }
1389 
1390 // In SPIR-V address space casting can only happen to and from the Generic
1391 // storage class. We can also only cast Workgroup, CrossWorkgroup, or Function
1392 // pointers to and from Generic pointers. As such, we can convert e.g. from
1393 // Workgroup to Function by going via a Generic pointer as an intermediary. All
1394 // other combinations can only be done by a bitcast, and are probably not safe.
1395 bool SPIRVInstructionSelector::selectAddrSpaceCast(Register ResVReg,
1396                                                    const SPIRVType *ResType,
1397                                                    MachineInstr &I) const {
1398   MachineBasicBlock &BB = *I.getParent();
1399   const DebugLoc &DL = I.getDebugLoc();
1400 
1401   Register SrcPtr = I.getOperand(1).getReg();
1402   SPIRVType *SrcPtrTy = GR.getSPIRVTypeForVReg(SrcPtr);
1403 
1404   // don't generate a cast for a null that may be represented by OpTypeInt
1405   if (SrcPtrTy->getOpcode() != SPIRV::OpTypePointer ||
1406       ResType->getOpcode() != SPIRV::OpTypePointer)
1407     return BuildMI(BB, I, DL, TII.get(TargetOpcode::COPY))
1408         .addDef(ResVReg)
1409         .addUse(SrcPtr)
1410         .constrainAllUses(TII, TRI, RBI);
1411 
1412   SPIRV::StorageClass::StorageClass SrcSC = GR.getPointerStorageClass(SrcPtrTy);
1413   SPIRV::StorageClass::StorageClass DstSC = GR.getPointerStorageClass(ResType);
1414 
1415   if (isASCastInGVar(MRI, ResVReg)) {
1416     // AddrSpaceCast uses within OpVariable and OpConstantComposite instructions
1417     // are expressed by OpSpecConstantOp with an Opcode.
1418     // TODO: maybe insert a check whether the Kernel capability was declared and
1419     // so PtrCastToGeneric/GenericCastToPtr are available.
1420     unsigned SpecOpcode =
1421         DstSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(SrcSC)
1422             ? static_cast<uint32_t>(SPIRV::Opcode::PtrCastToGeneric)
1423             : (SrcSC == SPIRV::StorageClass::Generic &&
1424                        isGenericCastablePtr(DstSC)
1425                    ? static_cast<uint32_t>(SPIRV::Opcode::GenericCastToPtr)
1426                    : 0);
1427     // TODO: OpConstantComposite expects i8*, so we are forced to forget a
1428     // correct value of ResType and use general i8* instead. Maybe this should
1429     // be addressed in the emit-intrinsic step to infer a correct
1430     // OpConstantComposite type.
1431     if (SpecOpcode) {
1432       return buildSpecConstantOp(I, ResVReg, SrcPtr,
1433                                  getUcharPtrTypeReg(I, DstSC), SpecOpcode)
1434           .constrainAllUses(TII, TRI, RBI);
1435     } else if (isGenericCastablePtr(SrcSC) && isGenericCastablePtr(DstSC)) {
1436       MachineInstrBuilder MIB = buildConstGenericPtr(I, SrcPtr, SrcPtrTy);
1437       return MIB.constrainAllUses(TII, TRI, RBI) &&
1438              buildSpecConstantOp(
1439                  I, ResVReg, MIB->getOperand(0).getReg(),
1440                  getUcharPtrTypeReg(I, DstSC),
1441                  static_cast<uint32_t>(SPIRV::Opcode::GenericCastToPtr))
1442                  .constrainAllUses(TII, TRI, RBI);
1443     }
1444   }
1445 
1446   // don't generate a cast between identical storage classes
1447   if (SrcSC == DstSC)
1448     return BuildMI(BB, I, DL, TII.get(TargetOpcode::COPY))
1449         .addDef(ResVReg)
1450         .addUse(SrcPtr)
1451         .constrainAllUses(TII, TRI, RBI);
1452 
1453   // Casting from an eligible pointer to Generic.
1454   if (DstSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(SrcSC))
1455     return selectUnOp(ResVReg, ResType, I, SPIRV::OpPtrCastToGeneric);
1456   // Casting from Generic to an eligible pointer.
1457   if (SrcSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(DstSC))
1458     return selectUnOp(ResVReg, ResType, I, SPIRV::OpGenericCastToPtr);
1459   // Casting between 2 eligible pointers using Generic as an intermediary.
1460   if (isGenericCastablePtr(SrcSC) && isGenericCastablePtr(DstSC)) {
1461     Register Tmp = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1462     SPIRVType *GenericPtrTy = GR.getOrCreateSPIRVPointerType(
1463         GR.getPointeeType(SrcPtrTy), I, TII, SPIRV::StorageClass::Generic);
1464     bool Result = BuildMI(BB, I, DL, TII.get(SPIRV::OpPtrCastToGeneric))
1465                       .addDef(Tmp)
1466                       .addUse(GR.getSPIRVTypeID(GenericPtrTy))
1467                       .addUse(SrcPtr)
1468                       .constrainAllUses(TII, TRI, RBI);
1469     return Result && BuildMI(BB, I, DL, TII.get(SPIRV::OpGenericCastToPtr))
1470                          .addDef(ResVReg)
1471                          .addUse(GR.getSPIRVTypeID(ResType))
1472                          .addUse(Tmp)
1473                          .constrainAllUses(TII, TRI, RBI);
1474   }
1475 
1476   // Check if instructions from the SPV_INTEL_usm_storage_classes extension may
1477   // be applied
1478   if (isUSMStorageClass(SrcSC) && DstSC == SPIRV::StorageClass::CrossWorkgroup)
1479     return selectUnOp(ResVReg, ResType, I,
1480                       SPIRV::OpPtrCastToCrossWorkgroupINTEL);
1481   if (SrcSC == SPIRV::StorageClass::CrossWorkgroup && isUSMStorageClass(DstSC))
1482     return selectUnOp(ResVReg, ResType, I,
1483                       SPIRV::OpCrossWorkgroupCastToPtrINTEL);
1484   if (isUSMStorageClass(SrcSC) && DstSC == SPIRV::StorageClass::Generic)
1485     return selectUnOp(ResVReg, ResType, I, SPIRV::OpPtrCastToGeneric);
1486   if (SrcSC == SPIRV::StorageClass::Generic && isUSMStorageClass(DstSC))
1487     return selectUnOp(ResVReg, ResType, I, SPIRV::OpGenericCastToPtr);
1488 
1489   // Bitcast for pointers requires that the address spaces must match
1490   return false;
1491 }
1492 
1493 static unsigned getFCmpOpcode(unsigned PredNum) {
1494   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1495   switch (Pred) {
1496   case CmpInst::FCMP_OEQ:
1497     return SPIRV::OpFOrdEqual;
1498   case CmpInst::FCMP_OGE:
1499     return SPIRV::OpFOrdGreaterThanEqual;
1500   case CmpInst::FCMP_OGT:
1501     return SPIRV::OpFOrdGreaterThan;
1502   case CmpInst::FCMP_OLE:
1503     return SPIRV::OpFOrdLessThanEqual;
1504   case CmpInst::FCMP_OLT:
1505     return SPIRV::OpFOrdLessThan;
1506   case CmpInst::FCMP_ONE:
1507     return SPIRV::OpFOrdNotEqual;
1508   case CmpInst::FCMP_ORD:
1509     return SPIRV::OpOrdered;
1510   case CmpInst::FCMP_UEQ:
1511     return SPIRV::OpFUnordEqual;
1512   case CmpInst::FCMP_UGE:
1513     return SPIRV::OpFUnordGreaterThanEqual;
1514   case CmpInst::FCMP_UGT:
1515     return SPIRV::OpFUnordGreaterThan;
1516   case CmpInst::FCMP_ULE:
1517     return SPIRV::OpFUnordLessThanEqual;
1518   case CmpInst::FCMP_ULT:
1519     return SPIRV::OpFUnordLessThan;
1520   case CmpInst::FCMP_UNE:
1521     return SPIRV::OpFUnordNotEqual;
1522   case CmpInst::FCMP_UNO:
1523     return SPIRV::OpUnordered;
1524   default:
1525     llvm_unreachable("Unknown predicate type for FCmp");
1526   }
1527 }
1528 
1529 static unsigned getICmpOpcode(unsigned PredNum) {
1530   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1531   switch (Pred) {
1532   case CmpInst::ICMP_EQ:
1533     return SPIRV::OpIEqual;
1534   case CmpInst::ICMP_NE:
1535     return SPIRV::OpINotEqual;
1536   case CmpInst::ICMP_SGE:
1537     return SPIRV::OpSGreaterThanEqual;
1538   case CmpInst::ICMP_SGT:
1539     return SPIRV::OpSGreaterThan;
1540   case CmpInst::ICMP_SLE:
1541     return SPIRV::OpSLessThanEqual;
1542   case CmpInst::ICMP_SLT:
1543     return SPIRV::OpSLessThan;
1544   case CmpInst::ICMP_UGE:
1545     return SPIRV::OpUGreaterThanEqual;
1546   case CmpInst::ICMP_UGT:
1547     return SPIRV::OpUGreaterThan;
1548   case CmpInst::ICMP_ULE:
1549     return SPIRV::OpULessThanEqual;
1550   case CmpInst::ICMP_ULT:
1551     return SPIRV::OpULessThan;
1552   default:
1553     llvm_unreachable("Unknown predicate type for ICmp");
1554   }
1555 }
1556 
1557 static unsigned getPtrCmpOpcode(unsigned Pred) {
1558   switch (static_cast<CmpInst::Predicate>(Pred)) {
1559   case CmpInst::ICMP_EQ:
1560     return SPIRV::OpPtrEqual;
1561   case CmpInst::ICMP_NE:
1562     return SPIRV::OpPtrNotEqual;
1563   default:
1564     llvm_unreachable("Unknown predicate type for pointer comparison");
1565   }
1566 }
1567 
1568 // Return the logical operation, or abort if none exists.
1569 static unsigned getBoolCmpOpcode(unsigned PredNum) {
1570   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1571   switch (Pred) {
1572   case CmpInst::ICMP_EQ:
1573     return SPIRV::OpLogicalEqual;
1574   case CmpInst::ICMP_NE:
1575     return SPIRV::OpLogicalNotEqual;
1576   default:
1577     llvm_unreachable("Unknown predicate type for Bool comparison");
1578   }
1579 }
1580 
1581 static APFloat getZeroFP(const Type *LLVMFloatTy) {
1582   if (!LLVMFloatTy)
1583     return APFloat::getZero(APFloat::IEEEsingle());
1584   switch (LLVMFloatTy->getScalarType()->getTypeID()) {
1585   case Type::HalfTyID:
1586     return APFloat::getZero(APFloat::IEEEhalf());
1587   default:
1588   case Type::FloatTyID:
1589     return APFloat::getZero(APFloat::IEEEsingle());
1590   case Type::DoubleTyID:
1591     return APFloat::getZero(APFloat::IEEEdouble());
1592   }
1593 }
1594 
1595 static APFloat getOneFP(const Type *LLVMFloatTy) {
1596   if (!LLVMFloatTy)
1597     return APFloat::getOne(APFloat::IEEEsingle());
1598   switch (LLVMFloatTy->getScalarType()->getTypeID()) {
1599   case Type::HalfTyID:
1600     return APFloat::getOne(APFloat::IEEEhalf());
1601   default:
1602   case Type::FloatTyID:
1603     return APFloat::getOne(APFloat::IEEEsingle());
1604   case Type::DoubleTyID:
1605     return APFloat::getOne(APFloat::IEEEdouble());
1606   }
1607 }
1608 
1609 bool SPIRVInstructionSelector::selectAnyOrAll(Register ResVReg,
1610                                               const SPIRVType *ResType,
1611                                               MachineInstr &I,
1612                                               unsigned OpAnyOrAll) const {
1613   assert(I.getNumOperands() == 3);
1614   assert(I.getOperand(2).isReg());
1615   MachineBasicBlock &BB = *I.getParent();
1616   Register InputRegister = I.getOperand(2).getReg();
1617   SPIRVType *InputType = GR.getSPIRVTypeForVReg(InputRegister);
1618 
1619   if (!InputType)
1620     report_fatal_error("Input Type could not be determined.");
1621 
1622   bool IsBoolTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeBool);
1623   bool IsVectorTy = InputType->getOpcode() == SPIRV::OpTypeVector;
1624   if (IsBoolTy && !IsVectorTy) {
1625     assert(ResVReg == I.getOperand(0).getReg());
1626     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1627                    TII.get(TargetOpcode::COPY))
1628         .addDef(ResVReg)
1629         .addUse(InputRegister)
1630         .constrainAllUses(TII, TRI, RBI);
1631   }
1632 
1633   bool IsFloatTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeFloat);
1634   unsigned SpirvNotEqualId =
1635       IsFloatTy ? SPIRV::OpFOrdNotEqual : SPIRV::OpINotEqual;
1636   SPIRVType *SpvBoolScalarTy = GR.getOrCreateSPIRVBoolType(I, TII);
1637   SPIRVType *SpvBoolTy = SpvBoolScalarTy;
1638   Register NotEqualReg = ResVReg;
1639 
1640   if (IsVectorTy) {
1641     NotEqualReg = IsBoolTy ? InputRegister
1642                            : MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1643     const unsigned NumElts = InputType->getOperand(2).getImm();
1644     SpvBoolTy = GR.getOrCreateSPIRVVectorType(SpvBoolTy, NumElts, I, TII);
1645   }
1646 
1647   bool Result = true;
1648   if (!IsBoolTy) {
1649     Register ConstZeroReg =
1650         IsFloatTy ? buildZerosValF(InputType, I) : buildZerosVal(InputType, I);
1651 
1652     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SpirvNotEqualId))
1653                   .addDef(NotEqualReg)
1654                   .addUse(GR.getSPIRVTypeID(SpvBoolTy))
1655                   .addUse(InputRegister)
1656                   .addUse(ConstZeroReg)
1657                   .constrainAllUses(TII, TRI, RBI);
1658   }
1659 
1660   if (!IsVectorTy)
1661     return Result;
1662 
1663   return Result && BuildMI(BB, I, I.getDebugLoc(), TII.get(OpAnyOrAll))
1664                        .addDef(ResVReg)
1665                        .addUse(GR.getSPIRVTypeID(SpvBoolScalarTy))
1666                        .addUse(NotEqualReg)
1667                        .constrainAllUses(TII, TRI, RBI);
1668 }
1669 
1670 bool SPIRVInstructionSelector::selectAll(Register ResVReg,
1671                                          const SPIRVType *ResType,
1672                                          MachineInstr &I) const {
1673   return selectAnyOrAll(ResVReg, ResType, I, SPIRV::OpAll);
1674 }
1675 
1676 bool SPIRVInstructionSelector::selectAny(Register ResVReg,
1677                                          const SPIRVType *ResType,
1678                                          MachineInstr &I) const {
1679   return selectAnyOrAll(ResVReg, ResType, I, SPIRV::OpAny);
1680 }
1681 
1682 // Select the OpDot instruction for the given float dot
1683 bool SPIRVInstructionSelector::selectFloatDot(Register ResVReg,
1684                                               const SPIRVType *ResType,
1685                                               MachineInstr &I) const {
1686   assert(I.getNumOperands() == 4);
1687   assert(I.getOperand(2).isReg());
1688   assert(I.getOperand(3).isReg());
1689 
1690   [[maybe_unused]] SPIRVType *VecType =
1691       GR.getSPIRVTypeForVReg(I.getOperand(2).getReg());
1692 
1693   assert(VecType->getOpcode() == SPIRV::OpTypeVector &&
1694          GR.getScalarOrVectorComponentCount(VecType) > 1 &&
1695          "dot product requires a vector of at least 2 components");
1696 
1697   [[maybe_unused]] SPIRVType *EltType =
1698       GR.getSPIRVTypeForVReg(VecType->getOperand(1).getReg());
1699 
1700   assert(EltType->getOpcode() == SPIRV::OpTypeFloat);
1701 
1702   MachineBasicBlock &BB = *I.getParent();
1703   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpDot))
1704       .addDef(ResVReg)
1705       .addUse(GR.getSPIRVTypeID(ResType))
1706       .addUse(I.getOperand(2).getReg())
1707       .addUse(I.getOperand(3).getReg())
1708       .constrainAllUses(TII, TRI, RBI);
1709 }
1710 
1711 // Since pre-1.6 SPIRV has no integer dot implementation,
1712 // expand by piecewise multiplying and adding the results
1713 bool SPIRVInstructionSelector::selectIntegerDot(Register ResVReg,
1714                                                 const SPIRVType *ResType,
1715                                                 MachineInstr &I) const {
1716   assert(I.getNumOperands() == 4);
1717   assert(I.getOperand(2).isReg());
1718   assert(I.getOperand(3).isReg());
1719   MachineBasicBlock &BB = *I.getParent();
1720 
1721   // Multiply the vectors, then sum the results
1722   Register Vec0 = I.getOperand(2).getReg();
1723   Register Vec1 = I.getOperand(3).getReg();
1724   Register TmpVec = MRI->createVirtualRegister(GR.getRegClass(ResType));
1725   SPIRVType *VecType = GR.getSPIRVTypeForVReg(Vec0);
1726 
1727   bool Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIMulV))
1728                     .addDef(TmpVec)
1729                     .addUse(GR.getSPIRVTypeID(VecType))
1730                     .addUse(Vec0)
1731                     .addUse(Vec1)
1732                     .constrainAllUses(TII, TRI, RBI);
1733 
1734   assert(VecType->getOpcode() == SPIRV::OpTypeVector &&
1735          GR.getScalarOrVectorComponentCount(VecType) > 1 &&
1736          "dot product requires a vector of at least 2 components");
1737 
1738   Register Res = MRI->createVirtualRegister(GR.getRegClass(ResType));
1739   Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1740                 .addDef(Res)
1741                 .addUse(GR.getSPIRVTypeID(ResType))
1742                 .addUse(TmpVec)
1743                 .addImm(0)
1744                 .constrainAllUses(TII, TRI, RBI);
1745 
1746   for (unsigned i = 1; i < GR.getScalarOrVectorComponentCount(VecType); i++) {
1747     Register Elt = MRI->createVirtualRegister(GR.getRegClass(ResType));
1748 
1749     Result &=
1750         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1751             .addDef(Elt)
1752             .addUse(GR.getSPIRVTypeID(ResType))
1753             .addUse(TmpVec)
1754             .addImm(i)
1755             .constrainAllUses(TII, TRI, RBI);
1756 
1757     Register Sum = i < GR.getScalarOrVectorComponentCount(VecType) - 1
1758                        ? MRI->createVirtualRegister(GR.getRegClass(ResType))
1759                        : ResVReg;
1760 
1761     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIAddS))
1762                   .addDef(Sum)
1763                   .addUse(GR.getSPIRVTypeID(ResType))
1764                   .addUse(Res)
1765                   .addUse(Elt)
1766                   .constrainAllUses(TII, TRI, RBI);
1767     Res = Sum;
1768   }
1769 
1770   return Result;
1771 }
1772 
1773 template <bool Signed>
1774 bool SPIRVInstructionSelector::selectDot4AddPacked(Register ResVReg,
1775                                                    const SPIRVType *ResType,
1776                                                    MachineInstr &I) const {
1777   assert(I.getNumOperands() == 5);
1778   assert(I.getOperand(2).isReg());
1779   assert(I.getOperand(3).isReg());
1780   assert(I.getOperand(4).isReg());
1781   MachineBasicBlock &BB = *I.getParent();
1782 
1783   auto DotOp = Signed ? SPIRV::OpSDot : SPIRV::OpUDot;
1784   Register Dot = MRI->createVirtualRegister(GR.getRegClass(ResType));
1785   bool Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(DotOp))
1786                     .addDef(Dot)
1787                     .addUse(GR.getSPIRVTypeID(ResType))
1788                     .addUse(I.getOperand(2).getReg())
1789                     .addUse(I.getOperand(3).getReg())
1790                     .constrainAllUses(TII, TRI, RBI);
1791 
1792   return Result && BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIAddS))
1793                        .addDef(ResVReg)
1794                        .addUse(GR.getSPIRVTypeID(ResType))
1795                        .addUse(Dot)
1796                        .addUse(I.getOperand(4).getReg())
1797                        .constrainAllUses(TII, TRI, RBI);
1798 }
1799 
1800 // Since pre-1.6 SPIRV has no DotProductInput4x8BitPacked implementation,
1801 // extract the elements of the packed inputs, multiply them and add the result
1802 // to the accumulator.
1803 template <bool Signed>
1804 bool SPIRVInstructionSelector::selectDot4AddPackedExpansion(
1805     Register ResVReg, const SPIRVType *ResType, MachineInstr &I) const {
1806   assert(I.getNumOperands() == 5);
1807   assert(I.getOperand(2).isReg());
1808   assert(I.getOperand(3).isReg());
1809   assert(I.getOperand(4).isReg());
1810   MachineBasicBlock &BB = *I.getParent();
1811 
1812   bool Result = true;
1813 
1814   // Acc = C
1815   Register Acc = I.getOperand(4).getReg();
1816   SPIRVType *EltType = GR.getOrCreateSPIRVIntegerType(8, I, TII);
1817   auto ExtractOp =
1818       Signed ? SPIRV::OpBitFieldSExtract : SPIRV::OpBitFieldUExtract;
1819 
1820   // Extract the i8 element, multiply and add it to the accumulator
1821   for (unsigned i = 0; i < 4; i++) {
1822     // A[i]
1823     Register AElt = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1824     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(ExtractOp))
1825                   .addDef(AElt)
1826                   .addUse(GR.getSPIRVTypeID(ResType))
1827                   .addUse(I.getOperand(2).getReg())
1828                   .addUse(GR.getOrCreateConstInt(i * 8, I, EltType, TII))
1829                   .addUse(GR.getOrCreateConstInt(8, I, EltType, TII))
1830                   .constrainAllUses(TII, TRI, RBI);
1831 
1832     // B[i]
1833     Register BElt = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1834     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(ExtractOp))
1835                   .addDef(BElt)
1836                   .addUse(GR.getSPIRVTypeID(ResType))
1837                   .addUse(I.getOperand(3).getReg())
1838                   .addUse(GR.getOrCreateConstInt(i * 8, I, EltType, TII))
1839                   .addUse(GR.getOrCreateConstInt(8, I, EltType, TII))
1840                   .constrainAllUses(TII, TRI, RBI);
1841 
1842     // A[i] * B[i]
1843     Register Mul = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1844     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIMulS))
1845                   .addDef(Mul)
1846                   .addUse(GR.getSPIRVTypeID(ResType))
1847                   .addUse(AElt)
1848                   .addUse(BElt)
1849                   .constrainAllUses(TII, TRI, RBI);
1850 
1851     // Discard 24 highest-bits so that stored i32 register is i8 equivalent
1852     Register MaskMul = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1853     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(ExtractOp))
1854                   .addDef(MaskMul)
1855                   .addUse(GR.getSPIRVTypeID(ResType))
1856                   .addUse(Mul)
1857                   .addUse(GR.getOrCreateConstInt(0, I, EltType, TII))
1858                   .addUse(GR.getOrCreateConstInt(8, I, EltType, TII))
1859                   .constrainAllUses(TII, TRI, RBI);
1860 
1861     // Acc = Acc + A[i] * B[i]
1862     Register Sum =
1863         i < 3 ? MRI->createVirtualRegister(&SPIRV::IDRegClass) : ResVReg;
1864     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIAddS))
1865                   .addDef(Sum)
1866                   .addUse(GR.getSPIRVTypeID(ResType))
1867                   .addUse(Acc)
1868                   .addUse(MaskMul)
1869                   .constrainAllUses(TII, TRI, RBI);
1870 
1871     Acc = Sum;
1872   }
1873 
1874   return Result;
1875 }
1876 
1877 /// Transform saturate(x) to clamp(x, 0.0f, 1.0f) as SPIRV
1878 /// does not have a saturate builtin.
1879 bool SPIRVInstructionSelector::selectSaturate(Register ResVReg,
1880                                               const SPIRVType *ResType,
1881                                               MachineInstr &I) const {
1882   assert(I.getNumOperands() == 3);
1883   assert(I.getOperand(2).isReg());
1884   MachineBasicBlock &BB = *I.getParent();
1885   Register VZero = buildZerosValF(ResType, I);
1886   Register VOne = buildOnesValF(ResType, I);
1887 
1888   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
1889       .addDef(ResVReg)
1890       .addUse(GR.getSPIRVTypeID(ResType))
1891       .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
1892       .addImm(GL::FClamp)
1893       .addUse(I.getOperand(2).getReg())
1894       .addUse(VZero)
1895       .addUse(VOne)
1896       .constrainAllUses(TII, TRI, RBI);
1897 }
1898 
1899 bool SPIRVInstructionSelector::selectSign(Register ResVReg,
1900                                           const SPIRVType *ResType,
1901                                           MachineInstr &I) const {
1902   assert(I.getNumOperands() == 3);
1903   assert(I.getOperand(2).isReg());
1904   MachineBasicBlock &BB = *I.getParent();
1905   Register InputRegister = I.getOperand(2).getReg();
1906   SPIRVType *InputType = GR.getSPIRVTypeForVReg(InputRegister);
1907   auto &DL = I.getDebugLoc();
1908 
1909   if (!InputType)
1910     report_fatal_error("Input Type could not be determined.");
1911 
1912   bool IsFloatTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeFloat);
1913 
1914   unsigned SignBitWidth = GR.getScalarOrVectorBitWidth(InputType);
1915   unsigned ResBitWidth = GR.getScalarOrVectorBitWidth(ResType);
1916 
1917   bool NeedsConversion = IsFloatTy || SignBitWidth != ResBitWidth;
1918 
1919   auto SignOpcode = IsFloatTy ? GL::FSign : GL::SSign;
1920   Register SignReg = NeedsConversion
1921                          ? MRI->createVirtualRegister(&SPIRV::IDRegClass)
1922                          : ResVReg;
1923 
1924   bool Result =
1925       BuildMI(BB, I, DL, TII.get(SPIRV::OpExtInst))
1926           .addDef(SignReg)
1927           .addUse(GR.getSPIRVTypeID(InputType))
1928           .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
1929           .addImm(SignOpcode)
1930           .addUse(InputRegister)
1931           .constrainAllUses(TII, TRI, RBI);
1932 
1933   if (NeedsConversion) {
1934     auto ConvertOpcode = IsFloatTy ? SPIRV::OpConvertFToS : SPIRV::OpSConvert;
1935     Result &= BuildMI(*I.getParent(), I, DL, TII.get(ConvertOpcode))
1936                   .addDef(ResVReg)
1937                   .addUse(GR.getSPIRVTypeID(ResType))
1938                   .addUse(SignReg)
1939                   .constrainAllUses(TII, TRI, RBI);
1940   }
1941 
1942   return Result;
1943 }
1944 
1945 bool SPIRVInstructionSelector::selectWaveActiveCountBits(
1946     Register ResVReg, const SPIRVType *ResType, MachineInstr &I) const {
1947   assert(I.getNumOperands() == 3);
1948   assert(I.getOperand(2).isReg());
1949   MachineBasicBlock &BB = *I.getParent();
1950 
1951   SPIRVType *IntTy = GR.getOrCreateSPIRVIntegerType(32, I, TII);
1952   SPIRVType *BallotType = GR.getOrCreateSPIRVVectorType(IntTy, 4, I, TII);
1953   Register BallotReg = MRI->createVirtualRegister(GR.getRegClass(BallotType));
1954 
1955   bool Result =
1956       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpGroupNonUniformBallot))
1957           .addDef(BallotReg)
1958           .addUse(GR.getSPIRVTypeID(BallotType))
1959           .addUse(GR.getOrCreateConstInt(SPIRV::Scope::Subgroup, I, IntTy, TII))
1960           .addUse(I.getOperand(2).getReg())
1961           .constrainAllUses(TII, TRI, RBI);
1962 
1963   Result &=
1964       BuildMI(BB, I, I.getDebugLoc(),
1965               TII.get(SPIRV::OpGroupNonUniformBallotBitCount))
1966           .addDef(ResVReg)
1967           .addUse(GR.getSPIRVTypeID(ResType))
1968           .addUse(GR.getOrCreateConstInt(SPIRV::Scope::Subgroup, I, IntTy, TII))
1969           .addImm(SPIRV::GroupOperation::Reduce)
1970           .addUse(BallotReg)
1971           .constrainAllUses(TII, TRI, RBI);
1972 
1973   return Result;
1974 }
1975 
1976 bool SPIRVInstructionSelector::selectWaveReadLaneAt(Register ResVReg,
1977                                                     const SPIRVType *ResType,
1978                                                     MachineInstr &I) const {
1979   assert(I.getNumOperands() == 4);
1980   assert(I.getOperand(2).isReg());
1981   assert(I.getOperand(3).isReg());
1982   MachineBasicBlock &BB = *I.getParent();
1983 
1984   // IntTy is used to define the execution scope, set to 3 to denote a
1985   // cross-lane interaction equivalent to a SPIR-V subgroup.
1986   SPIRVType *IntTy = GR.getOrCreateSPIRVIntegerType(32, I, TII);
1987   return BuildMI(BB, I, I.getDebugLoc(),
1988                  TII.get(SPIRV::OpGroupNonUniformShuffle))
1989       .addDef(ResVReg)
1990       .addUse(GR.getSPIRVTypeID(ResType))
1991       .addUse(GR.getOrCreateConstInt(3, I, IntTy, TII))
1992       .addUse(I.getOperand(2).getReg())
1993       .addUse(I.getOperand(3).getReg());
1994 }
1995 
1996 bool SPIRVInstructionSelector::selectBitreverse(Register ResVReg,
1997                                                 const SPIRVType *ResType,
1998                                                 MachineInstr &I) const {
1999   MachineBasicBlock &BB = *I.getParent();
2000   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpBitReverse))
2001       .addDef(ResVReg)
2002       .addUse(GR.getSPIRVTypeID(ResType))
2003       .addUse(I.getOperand(1).getReg())
2004       .constrainAllUses(TII, TRI, RBI);
2005 }
2006 
2007 bool SPIRVInstructionSelector::selectFreeze(Register ResVReg,
2008                                             const SPIRVType *ResType,
2009                                             MachineInstr &I) const {
2010   // There is no way to implement `freeze` correctly without support on SPIR-V
2011   // standard side, but we may at least address a simple (static) case when
2012   // undef/poison value presence is obvious. The main benefit of even
2013   // incomplete `freeze` support is preventing of translation from crashing due
2014   // to lack of support on legalization and instruction selection steps.
2015   if (!I.getOperand(0).isReg() || !I.getOperand(1).isReg())
2016     return false;
2017   Register OpReg = I.getOperand(1).getReg();
2018   if (MachineInstr *Def = MRI->getVRegDef(OpReg)) {
2019     Register Reg;
2020     switch (Def->getOpcode()) {
2021     case SPIRV::ASSIGN_TYPE:
2022       if (MachineInstr *AssignToDef =
2023               MRI->getVRegDef(Def->getOperand(1).getReg())) {
2024         if (AssignToDef->getOpcode() == TargetOpcode::G_IMPLICIT_DEF)
2025           Reg = Def->getOperand(2).getReg();
2026       }
2027       break;
2028     case SPIRV::OpUndef:
2029       Reg = Def->getOperand(1).getReg();
2030       break;
2031     }
2032     unsigned DestOpCode;
2033     if (Reg.isValid()) {
2034       DestOpCode = SPIRV::OpConstantNull;
2035     } else {
2036       DestOpCode = TargetOpcode::COPY;
2037       Reg = OpReg;
2038     }
2039     return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(DestOpCode))
2040         .addDef(I.getOperand(0).getReg())
2041         .addUse(Reg)
2042         .constrainAllUses(TII, TRI, RBI);
2043   }
2044   return false;
2045 }
2046 
2047 static unsigned getArrayComponentCount(MachineRegisterInfo *MRI,
2048                                        const SPIRVType *ResType) {
2049   Register OpReg = ResType->getOperand(2).getReg();
2050   SPIRVType *OpDef = MRI->getVRegDef(OpReg);
2051   if (!OpDef)
2052     return 0;
2053   if (OpDef->getOpcode() == SPIRV::ASSIGN_TYPE &&
2054       OpDef->getOperand(1).isReg()) {
2055     if (SPIRVType *RefDef = MRI->getVRegDef(OpDef->getOperand(1).getReg()))
2056       OpDef = RefDef;
2057   }
2058   unsigned N = OpDef->getOpcode() == TargetOpcode::G_CONSTANT
2059                    ? OpDef->getOperand(1).getCImm()->getValue().getZExtValue()
2060                    : 0;
2061   return N;
2062 }
2063 
2064 // Return true if the type represents a constant register
2065 static bool isConstReg(MachineRegisterInfo *MRI, SPIRVType *OpDef,
2066                        SmallPtrSet<SPIRVType *, 4> &Visited) {
2067   if (OpDef->getOpcode() == SPIRV::ASSIGN_TYPE &&
2068       OpDef->getOperand(1).isReg()) {
2069     if (SPIRVType *RefDef = MRI->getVRegDef(OpDef->getOperand(1).getReg()))
2070       OpDef = RefDef;
2071   }
2072 
2073   if (Visited.contains(OpDef))
2074     return true;
2075   Visited.insert(OpDef);
2076 
2077   unsigned Opcode = OpDef->getOpcode();
2078   switch (Opcode) {
2079   case TargetOpcode::G_CONSTANT:
2080   case TargetOpcode::G_FCONSTANT:
2081     return true;
2082   case TargetOpcode::G_INTRINSIC:
2083   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
2084   case TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS:
2085     return cast<GIntrinsic>(*OpDef).getIntrinsicID() ==
2086            Intrinsic::spv_const_composite;
2087   case TargetOpcode::G_BUILD_VECTOR:
2088   case TargetOpcode::G_SPLAT_VECTOR: {
2089     for (unsigned i = OpDef->getNumExplicitDefs(); i < OpDef->getNumOperands();
2090          i++) {
2091       SPIRVType *OpNestedDef =
2092           OpDef->getOperand(i).isReg()
2093               ? MRI->getVRegDef(OpDef->getOperand(i).getReg())
2094               : nullptr;
2095       if (OpNestedDef && !isConstReg(MRI, OpNestedDef, Visited))
2096         return false;
2097     }
2098     return true;
2099   }
2100   }
2101   return false;
2102 }
2103 
2104 // Return true if the virtual register represents a constant
2105 static bool isConstReg(MachineRegisterInfo *MRI, Register OpReg) {
2106   SmallPtrSet<SPIRVType *, 4> Visited;
2107   if (SPIRVType *OpDef = MRI->getVRegDef(OpReg))
2108     return isConstReg(MRI, OpDef, Visited);
2109   return false;
2110 }
2111 
2112 bool SPIRVInstructionSelector::selectBuildVector(Register ResVReg,
2113                                                  const SPIRVType *ResType,
2114                                                  MachineInstr &I) const {
2115   unsigned N = 0;
2116   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2117     N = GR.getScalarOrVectorComponentCount(ResType);
2118   else if (ResType->getOpcode() == SPIRV::OpTypeArray)
2119     N = getArrayComponentCount(MRI, ResType);
2120   else
2121     report_fatal_error("Cannot select G_BUILD_VECTOR with a non-vector result");
2122   if (I.getNumExplicitOperands() - I.getNumExplicitDefs() != N)
2123     report_fatal_error("G_BUILD_VECTOR and the result type are inconsistent");
2124 
2125   // check if we may construct a constant vector
2126   bool IsConst = true;
2127   for (unsigned i = I.getNumExplicitDefs();
2128        i < I.getNumExplicitOperands() && IsConst; ++i)
2129     if (!isConstReg(MRI, I.getOperand(i).getReg()))
2130       IsConst = false;
2131 
2132   if (!IsConst && N < 2)
2133     report_fatal_error(
2134         "There must be at least two constituent operands in a vector");
2135 
2136   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
2137                      TII.get(IsConst ? SPIRV::OpConstantComposite
2138                                      : SPIRV::OpCompositeConstruct))
2139                  .addDef(ResVReg)
2140                  .addUse(GR.getSPIRVTypeID(ResType));
2141   for (unsigned i = I.getNumExplicitDefs(); i < I.getNumExplicitOperands(); ++i)
2142     MIB.addUse(I.getOperand(i).getReg());
2143   return MIB.constrainAllUses(TII, TRI, RBI);
2144 }
2145 
2146 bool SPIRVInstructionSelector::selectSplatVector(Register ResVReg,
2147                                                  const SPIRVType *ResType,
2148                                                  MachineInstr &I) const {
2149   unsigned N = 0;
2150   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2151     N = GR.getScalarOrVectorComponentCount(ResType);
2152   else if (ResType->getOpcode() == SPIRV::OpTypeArray)
2153     N = getArrayComponentCount(MRI, ResType);
2154   else
2155     report_fatal_error("Cannot select G_SPLAT_VECTOR with a non-vector result");
2156 
2157   unsigned OpIdx = I.getNumExplicitDefs();
2158   if (!I.getOperand(OpIdx).isReg())
2159     report_fatal_error("Unexpected argument in G_SPLAT_VECTOR");
2160 
2161   // check if we may construct a constant vector
2162   Register OpReg = I.getOperand(OpIdx).getReg();
2163   bool IsConst = isConstReg(MRI, OpReg);
2164 
2165   if (!IsConst && N < 2)
2166     report_fatal_error(
2167         "There must be at least two constituent operands in a vector");
2168 
2169   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
2170                      TII.get(IsConst ? SPIRV::OpConstantComposite
2171                                      : SPIRV::OpCompositeConstruct))
2172                  .addDef(ResVReg)
2173                  .addUse(GR.getSPIRVTypeID(ResType));
2174   for (unsigned i = 0; i < N; ++i)
2175     MIB.addUse(OpReg);
2176   return MIB.constrainAllUses(TII, TRI, RBI);
2177 }
2178 
2179 bool SPIRVInstructionSelector::selectCmp(Register ResVReg,
2180                                          const SPIRVType *ResType,
2181                                          unsigned CmpOpc,
2182                                          MachineInstr &I) const {
2183   Register Cmp0 = I.getOperand(2).getReg();
2184   Register Cmp1 = I.getOperand(3).getReg();
2185   assert(GR.getSPIRVTypeForVReg(Cmp0)->getOpcode() ==
2186              GR.getSPIRVTypeForVReg(Cmp1)->getOpcode() &&
2187          "CMP operands should have the same type");
2188   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(CmpOpc))
2189       .addDef(ResVReg)
2190       .addUse(GR.getSPIRVTypeID(ResType))
2191       .addUse(Cmp0)
2192       .addUse(Cmp1)
2193       .constrainAllUses(TII, TRI, RBI);
2194 }
2195 
2196 bool SPIRVInstructionSelector::selectICmp(Register ResVReg,
2197                                           const SPIRVType *ResType,
2198                                           MachineInstr &I) const {
2199   auto Pred = I.getOperand(1).getPredicate();
2200   unsigned CmpOpc;
2201 
2202   Register CmpOperand = I.getOperand(2).getReg();
2203   if (GR.isScalarOfType(CmpOperand, SPIRV::OpTypePointer))
2204     CmpOpc = getPtrCmpOpcode(Pred);
2205   else if (GR.isScalarOrVectorOfType(CmpOperand, SPIRV::OpTypeBool))
2206     CmpOpc = getBoolCmpOpcode(Pred);
2207   else
2208     CmpOpc = getICmpOpcode(Pred);
2209   return selectCmp(ResVReg, ResType, CmpOpc, I);
2210 }
2211 
2212 void SPIRVInstructionSelector::renderFImm64(MachineInstrBuilder &MIB,
2213                                             const MachineInstr &I,
2214                                             int OpIdx) const {
2215   assert(I.getOpcode() == TargetOpcode::G_FCONSTANT && OpIdx == -1 &&
2216          "Expected G_FCONSTANT");
2217   const ConstantFP *FPImm = I.getOperand(1).getFPImm();
2218   addNumImm(FPImm->getValueAPF().bitcastToAPInt(), MIB);
2219 }
2220 
2221 void SPIRVInstructionSelector::renderImm32(MachineInstrBuilder &MIB,
2222                                            const MachineInstr &I,
2223                                            int OpIdx) const {
2224   assert(I.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
2225          "Expected G_CONSTANT");
2226   addNumImm(I.getOperand(1).getCImm()->getValue(), MIB);
2227 }
2228 
2229 std::pair<Register, bool>
2230 SPIRVInstructionSelector::buildI32Constant(uint32_t Val, MachineInstr &I,
2231                                            const SPIRVType *ResType) const {
2232   Type *LLVMTy = IntegerType::get(GR.CurMF->getFunction().getContext(), 32);
2233   const SPIRVType *SpvI32Ty =
2234       ResType ? ResType : GR.getOrCreateSPIRVIntegerType(32, I, TII);
2235   // Find a constant in DT or build a new one.
2236   auto ConstInt = ConstantInt::get(LLVMTy, Val);
2237   Register NewReg = GR.find(ConstInt, GR.CurMF);
2238   bool Result = true;
2239   if (!NewReg.isValid()) {
2240     NewReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
2241     GR.add(ConstInt, GR.CurMF, NewReg);
2242     MachineInstr *MI;
2243     MachineBasicBlock &BB = *I.getParent();
2244     if (Val == 0) {
2245       MI = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
2246                .addDef(NewReg)
2247                .addUse(GR.getSPIRVTypeID(SpvI32Ty));
2248     } else {
2249       MI = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantI))
2250                .addDef(NewReg)
2251                .addUse(GR.getSPIRVTypeID(SpvI32Ty))
2252                .addImm(APInt(32, Val).getZExtValue());
2253     }
2254     Result &= constrainSelectedInstRegOperands(*MI, TII, TRI, RBI);
2255   }
2256   return {NewReg, Result};
2257 }
2258 
2259 bool SPIRVInstructionSelector::selectFCmp(Register ResVReg,
2260                                           const SPIRVType *ResType,
2261                                           MachineInstr &I) const {
2262   unsigned CmpOp = getFCmpOpcode(I.getOperand(1).getPredicate());
2263   return selectCmp(ResVReg, ResType, CmpOp, I);
2264 }
2265 
2266 Register SPIRVInstructionSelector::buildZerosVal(const SPIRVType *ResType,
2267                                                  MachineInstr &I) const {
2268   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
2269   bool ZeroAsNull = STI.isOpenCLEnv();
2270   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2271     return GR.getOrCreateConstVector(0UL, I, ResType, TII, ZeroAsNull);
2272   return GR.getOrCreateConstInt(0, I, ResType, TII, ZeroAsNull);
2273 }
2274 
2275 Register SPIRVInstructionSelector::buildZerosValF(const SPIRVType *ResType,
2276                                                   MachineInstr &I) const {
2277   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
2278   bool ZeroAsNull = STI.isOpenCLEnv();
2279   APFloat VZero = getZeroFP(GR.getTypeForSPIRVType(ResType));
2280   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2281     return GR.getOrCreateConstVector(VZero, I, ResType, TII, ZeroAsNull);
2282   return GR.getOrCreateConstFP(VZero, I, ResType, TII, ZeroAsNull);
2283 }
2284 
2285 Register SPIRVInstructionSelector::buildOnesValF(const SPIRVType *ResType,
2286                                                  MachineInstr &I) const {
2287   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
2288   bool ZeroAsNull = STI.isOpenCLEnv();
2289   APFloat VOne = getOneFP(GR.getTypeForSPIRVType(ResType));
2290   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2291     return GR.getOrCreateConstVector(VOne, I, ResType, TII, ZeroAsNull);
2292   return GR.getOrCreateConstFP(VOne, I, ResType, TII, ZeroAsNull);
2293 }
2294 
2295 Register SPIRVInstructionSelector::buildOnesVal(bool AllOnes,
2296                                                 const SPIRVType *ResType,
2297                                                 MachineInstr &I) const {
2298   unsigned BitWidth = GR.getScalarOrVectorBitWidth(ResType);
2299   APInt One =
2300       AllOnes ? APInt::getAllOnes(BitWidth) : APInt::getOneBitSet(BitWidth, 0);
2301   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2302     return GR.getOrCreateConstVector(One.getZExtValue(), I, ResType, TII);
2303   return GR.getOrCreateConstInt(One.getZExtValue(), I, ResType, TII);
2304 }
2305 
2306 bool SPIRVInstructionSelector::selectSelect(Register ResVReg,
2307                                             const SPIRVType *ResType,
2308                                             MachineInstr &I,
2309                                             bool IsSigned) const {
2310   // To extend a bool, we need to use OpSelect between constants.
2311   Register ZeroReg = buildZerosVal(ResType, I);
2312   Register OneReg = buildOnesVal(IsSigned, ResType, I);
2313   bool IsScalarBool =
2314       GR.isScalarOfType(I.getOperand(1).getReg(), SPIRV::OpTypeBool);
2315   unsigned Opcode =
2316       IsScalarBool ? SPIRV::OpSelectSISCond : SPIRV::OpSelectSIVCond;
2317   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
2318       .addDef(ResVReg)
2319       .addUse(GR.getSPIRVTypeID(ResType))
2320       .addUse(I.getOperand(1).getReg())
2321       .addUse(OneReg)
2322       .addUse(ZeroReg)
2323       .constrainAllUses(TII, TRI, RBI);
2324 }
2325 
2326 bool SPIRVInstructionSelector::selectIToF(Register ResVReg,
2327                                           const SPIRVType *ResType,
2328                                           MachineInstr &I, bool IsSigned,
2329                                           unsigned Opcode) const {
2330   Register SrcReg = I.getOperand(1).getReg();
2331   // We can convert bool value directly to float type without OpConvert*ToF,
2332   // however the translator generates OpSelect+OpConvert*ToF, so we do the same.
2333   if (GR.isScalarOrVectorOfType(I.getOperand(1).getReg(), SPIRV::OpTypeBool)) {
2334     unsigned BitWidth = GR.getScalarOrVectorBitWidth(ResType);
2335     SPIRVType *TmpType = GR.getOrCreateSPIRVIntegerType(BitWidth, I, TII);
2336     if (ResType->getOpcode() == SPIRV::OpTypeVector) {
2337       const unsigned NumElts = ResType->getOperand(2).getImm();
2338       TmpType = GR.getOrCreateSPIRVVectorType(TmpType, NumElts, I, TII);
2339     }
2340     SrcReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2341     selectSelect(SrcReg, TmpType, I, false);
2342   }
2343   return selectUnOpWithSrc(ResVReg, ResType, I, SrcReg, Opcode);
2344 }
2345 
2346 bool SPIRVInstructionSelector::selectExt(Register ResVReg,
2347                                          const SPIRVType *ResType,
2348                                          MachineInstr &I, bool IsSigned) const {
2349   Register SrcReg = I.getOperand(1).getReg();
2350   if (GR.isScalarOrVectorOfType(SrcReg, SPIRV::OpTypeBool))
2351     return selectSelect(ResVReg, ResType, I, IsSigned);
2352 
2353   SPIRVType *SrcType = GR.getSPIRVTypeForVReg(SrcReg);
2354   if (SrcType == ResType) {
2355     const TargetRegisterClass *DstRC = MRI->getRegClassOrNull(ResVReg);
2356     const TargetRegisterClass *SrcRC = MRI->getRegClassOrNull(SrcReg);
2357     if (DstRC != SrcRC && SrcRC)
2358       MRI->setRegClass(ResVReg, SrcRC);
2359     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
2360                    TII.get(TargetOpcode::COPY))
2361         .addDef(ResVReg)
2362         .addUse(SrcReg)
2363         .constrainAllUses(TII, TRI, RBI);
2364   }
2365 
2366   unsigned Opcode = IsSigned ? SPIRV::OpSConvert : SPIRV::OpUConvert;
2367   return selectUnOp(ResVReg, ResType, I, Opcode);
2368 }
2369 
2370 bool SPIRVInstructionSelector::selectIntToBool(Register IntReg,
2371                                                Register ResVReg,
2372                                                MachineInstr &I,
2373                                                const SPIRVType *IntTy,
2374                                                const SPIRVType *BoolTy) const {
2375   // To truncate to a bool, we use OpBitwiseAnd 1 and OpINotEqual to zero.
2376   Register BitIntReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2377   bool IsVectorTy = IntTy->getOpcode() == SPIRV::OpTypeVector;
2378   unsigned Opcode = IsVectorTy ? SPIRV::OpBitwiseAndV : SPIRV::OpBitwiseAndS;
2379   Register Zero = buildZerosVal(IntTy, I);
2380   Register One = buildOnesVal(false, IntTy, I);
2381   MachineBasicBlock &BB = *I.getParent();
2382   bool Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2383                     .addDef(BitIntReg)
2384                     .addUse(GR.getSPIRVTypeID(IntTy))
2385                     .addUse(IntReg)
2386                     .addUse(One)
2387                     .constrainAllUses(TII, TRI, RBI);
2388   return Result && BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpINotEqual))
2389                        .addDef(ResVReg)
2390                        .addUse(GR.getSPIRVTypeID(BoolTy))
2391                        .addUse(BitIntReg)
2392                        .addUse(Zero)
2393                        .constrainAllUses(TII, TRI, RBI);
2394 }
2395 
2396 bool SPIRVInstructionSelector::selectTrunc(Register ResVReg,
2397                                            const SPIRVType *ResType,
2398                                            MachineInstr &I) const {
2399   Register IntReg = I.getOperand(1).getReg();
2400   const SPIRVType *ArgType = GR.getSPIRVTypeForVReg(IntReg);
2401   if (GR.isScalarOrVectorOfType(ResVReg, SPIRV::OpTypeBool))
2402     return selectIntToBool(IntReg, ResVReg, I, ArgType, ResType);
2403   if (ArgType == ResType) {
2404     const TargetRegisterClass *DstRC = MRI->getRegClassOrNull(ResVReg);
2405     const TargetRegisterClass *SrcRC = MRI->getRegClassOrNull(IntReg);
2406     if (DstRC != SrcRC && SrcRC)
2407       MRI->setRegClass(ResVReg, SrcRC);
2408     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
2409                    TII.get(TargetOpcode::COPY))
2410         .addDef(ResVReg)
2411         .addUse(IntReg)
2412         .constrainAllUses(TII, TRI, RBI);
2413   }
2414   bool IsSigned = GR.isScalarOrVectorSigned(ResType);
2415   unsigned Opcode = IsSigned ? SPIRV::OpSConvert : SPIRV::OpUConvert;
2416   return selectUnOp(ResVReg, ResType, I, Opcode);
2417 }
2418 
2419 bool SPIRVInstructionSelector::selectConst(Register ResVReg,
2420                                            const SPIRVType *ResType,
2421                                            const APInt &Imm,
2422                                            MachineInstr &I) const {
2423   unsigned TyOpcode = ResType->getOpcode();
2424   assert(TyOpcode != SPIRV::OpTypePointer || Imm.isZero());
2425   MachineBasicBlock &BB = *I.getParent();
2426   if ((TyOpcode == SPIRV::OpTypePointer || TyOpcode == SPIRV::OpTypeEvent) &&
2427       Imm.isZero())
2428     return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
2429         .addDef(ResVReg)
2430         .addUse(GR.getSPIRVTypeID(ResType))
2431         .constrainAllUses(TII, TRI, RBI);
2432   if (TyOpcode == SPIRV::OpTypeInt) {
2433     assert(Imm.getBitWidth() <= 64 && "Unsupported integer width!");
2434     Register Reg = GR.getOrCreateConstInt(Imm.getZExtValue(), I, ResType, TII);
2435     if (Reg == ResVReg)
2436       return true;
2437     return BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY))
2438         .addDef(ResVReg)
2439         .addUse(Reg)
2440         .constrainAllUses(TII, TRI, RBI);
2441   }
2442   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantI))
2443                  .addDef(ResVReg)
2444                  .addUse(GR.getSPIRVTypeID(ResType));
2445   // <=32-bit integers should be caught by the sdag pattern.
2446   assert(Imm.getBitWidth() > 32);
2447   addNumImm(Imm, MIB);
2448   return MIB.constrainAllUses(TII, TRI, RBI);
2449 }
2450 
2451 bool SPIRVInstructionSelector::selectOpUndef(Register ResVReg,
2452                                              const SPIRVType *ResType,
2453                                              MachineInstr &I) const {
2454   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpUndef))
2455       .addDef(ResVReg)
2456       .addUse(GR.getSPIRVTypeID(ResType))
2457       .constrainAllUses(TII, TRI, RBI);
2458 }
2459 
2460 static bool isImm(const MachineOperand &MO, MachineRegisterInfo *MRI) {
2461   assert(MO.isReg());
2462   const SPIRVType *TypeInst = MRI->getVRegDef(MO.getReg());
2463   if (TypeInst->getOpcode() == SPIRV::ASSIGN_TYPE) {
2464     assert(TypeInst->getOperand(1).isReg());
2465     MachineInstr *ImmInst = MRI->getVRegDef(TypeInst->getOperand(1).getReg());
2466     return ImmInst->getOpcode() == TargetOpcode::G_CONSTANT;
2467   }
2468   return TypeInst->getOpcode() == SPIRV::OpConstantI;
2469 }
2470 
2471 static int64_t foldImm(const MachineOperand &MO, MachineRegisterInfo *MRI) {
2472   const SPIRVType *TypeInst = MRI->getVRegDef(MO.getReg());
2473   if (TypeInst->getOpcode() == SPIRV::OpConstantI)
2474     return TypeInst->getOperand(2).getImm();
2475   MachineInstr *ImmInst = MRI->getVRegDef(TypeInst->getOperand(1).getReg());
2476   assert(ImmInst->getOpcode() == TargetOpcode::G_CONSTANT);
2477   return ImmInst->getOperand(1).getCImm()->getZExtValue();
2478 }
2479 
2480 bool SPIRVInstructionSelector::selectInsertVal(Register ResVReg,
2481                                                const SPIRVType *ResType,
2482                                                MachineInstr &I) const {
2483   MachineBasicBlock &BB = *I.getParent();
2484   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeInsert))
2485                  .addDef(ResVReg)
2486                  .addUse(GR.getSPIRVTypeID(ResType))
2487                  // object to insert
2488                  .addUse(I.getOperand(3).getReg())
2489                  // composite to insert into
2490                  .addUse(I.getOperand(2).getReg());
2491   for (unsigned i = 4; i < I.getNumOperands(); i++)
2492     MIB.addImm(foldImm(I.getOperand(i), MRI));
2493   return MIB.constrainAllUses(TII, TRI, RBI);
2494 }
2495 
2496 bool SPIRVInstructionSelector::selectExtractVal(Register ResVReg,
2497                                                 const SPIRVType *ResType,
2498                                                 MachineInstr &I) const {
2499   MachineBasicBlock &BB = *I.getParent();
2500   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
2501                  .addDef(ResVReg)
2502                  .addUse(GR.getSPIRVTypeID(ResType))
2503                  .addUse(I.getOperand(2).getReg());
2504   for (unsigned i = 3; i < I.getNumOperands(); i++)
2505     MIB.addImm(foldImm(I.getOperand(i), MRI));
2506   return MIB.constrainAllUses(TII, TRI, RBI);
2507 }
2508 
2509 bool SPIRVInstructionSelector::selectInsertElt(Register ResVReg,
2510                                                const SPIRVType *ResType,
2511                                                MachineInstr &I) const {
2512   if (isImm(I.getOperand(4), MRI))
2513     return selectInsertVal(ResVReg, ResType, I);
2514   MachineBasicBlock &BB = *I.getParent();
2515   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorInsertDynamic))
2516       .addDef(ResVReg)
2517       .addUse(GR.getSPIRVTypeID(ResType))
2518       .addUse(I.getOperand(2).getReg())
2519       .addUse(I.getOperand(3).getReg())
2520       .addUse(I.getOperand(4).getReg())
2521       .constrainAllUses(TII, TRI, RBI);
2522 }
2523 
2524 bool SPIRVInstructionSelector::selectExtractElt(Register ResVReg,
2525                                                 const SPIRVType *ResType,
2526                                                 MachineInstr &I) const {
2527   if (isImm(I.getOperand(3), MRI))
2528     return selectExtractVal(ResVReg, ResType, I);
2529   MachineBasicBlock &BB = *I.getParent();
2530   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorExtractDynamic))
2531       .addDef(ResVReg)
2532       .addUse(GR.getSPIRVTypeID(ResType))
2533       .addUse(I.getOperand(2).getReg())
2534       .addUse(I.getOperand(3).getReg())
2535       .constrainAllUses(TII, TRI, RBI);
2536 }
2537 
2538 bool SPIRVInstructionSelector::selectGEP(Register ResVReg,
2539                                          const SPIRVType *ResType,
2540                                          MachineInstr &I) const {
2541   const bool IsGEPInBounds = I.getOperand(2).getImm();
2542 
2543   // OpAccessChain could be used for OpenCL, but the SPIRV-LLVM Translator only
2544   // relies on PtrAccessChain, so we'll try not to deviate. For Vulkan however,
2545   // we have to use Op[InBounds]AccessChain.
2546   const unsigned Opcode = STI.isVulkanEnv()
2547                               ? (IsGEPInBounds ? SPIRV::OpInBoundsAccessChain
2548                                                : SPIRV::OpAccessChain)
2549                               : (IsGEPInBounds ? SPIRV::OpInBoundsPtrAccessChain
2550                                                : SPIRV::OpPtrAccessChain);
2551 
2552   auto Res = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
2553                  .addDef(ResVReg)
2554                  .addUse(GR.getSPIRVTypeID(ResType))
2555                  // Object to get a pointer to.
2556                  .addUse(I.getOperand(3).getReg());
2557   // Adding indices.
2558   const unsigned StartingIndex =
2559       (Opcode == SPIRV::OpAccessChain || Opcode == SPIRV::OpInBoundsAccessChain)
2560           ? 5
2561           : 4;
2562   for (unsigned i = StartingIndex; i < I.getNumExplicitOperands(); ++i)
2563     Res.addUse(I.getOperand(i).getReg());
2564   return Res.constrainAllUses(TII, TRI, RBI);
2565 }
2566 
2567 // Maybe wrap a value into OpSpecConstantOp
2568 bool SPIRVInstructionSelector::wrapIntoSpecConstantOp(
2569     MachineInstr &I, SmallVector<Register> &CompositeArgs) const {
2570   bool Result = true;
2571   unsigned Lim = I.getNumExplicitOperands();
2572   for (unsigned i = I.getNumExplicitDefs() + 1; i < Lim; ++i) {
2573     Register OpReg = I.getOperand(i).getReg();
2574     SPIRVType *OpDefine = MRI->getVRegDef(OpReg);
2575     SPIRVType *OpType = GR.getSPIRVTypeForVReg(OpReg);
2576     SmallPtrSet<SPIRVType *, 4> Visited;
2577     if (!OpDefine || !OpType || isConstReg(MRI, OpDefine, Visited) ||
2578         OpDefine->getOpcode() == TargetOpcode::G_ADDRSPACE_CAST ||
2579         GR.isAggregateType(OpType)) {
2580       // The case of G_ADDRSPACE_CAST inside spv_const_composite() is processed
2581       // by selectAddrSpaceCast()
2582       CompositeArgs.push_back(OpReg);
2583       continue;
2584     }
2585     MachineFunction *MF = I.getMF();
2586     Register WrapReg = GR.find(OpDefine, MF);
2587     if (WrapReg.isValid()) {
2588       CompositeArgs.push_back(WrapReg);
2589       continue;
2590     }
2591     // Create a new register for the wrapper
2592     WrapReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2593     GR.add(OpDefine, MF, WrapReg);
2594     CompositeArgs.push_back(WrapReg);
2595     // Decorate the wrapper register and generate a new instruction
2596     MRI->setType(WrapReg, LLT::pointer(0, 64));
2597     GR.assignSPIRVTypeToVReg(OpType, WrapReg, *MF);
2598     MachineBasicBlock &BB = *I.getParent();
2599     Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
2600                  .addDef(WrapReg)
2601                  .addUse(GR.getSPIRVTypeID(OpType))
2602                  .addImm(static_cast<uint32_t>(SPIRV::Opcode::Bitcast))
2603                  .addUse(OpReg)
2604                  .constrainAllUses(TII, TRI, RBI);
2605     if (!Result)
2606       break;
2607   }
2608   return Result;
2609 }
2610 
2611 bool SPIRVInstructionSelector::selectIntrinsic(Register ResVReg,
2612                                                const SPIRVType *ResType,
2613                                                MachineInstr &I) const {
2614   MachineBasicBlock &BB = *I.getParent();
2615   Intrinsic::ID IID = cast<GIntrinsic>(I).getIntrinsicID();
2616   switch (IID) {
2617   case Intrinsic::spv_load:
2618     return selectLoad(ResVReg, ResType, I);
2619   case Intrinsic::spv_store:
2620     return selectStore(I);
2621   case Intrinsic::spv_extractv:
2622     return selectExtractVal(ResVReg, ResType, I);
2623   case Intrinsic::spv_insertv:
2624     return selectInsertVal(ResVReg, ResType, I);
2625   case Intrinsic::spv_extractelt:
2626     return selectExtractElt(ResVReg, ResType, I);
2627   case Intrinsic::spv_insertelt:
2628     return selectInsertElt(ResVReg, ResType, I);
2629   case Intrinsic::spv_gep:
2630     return selectGEP(ResVReg, ResType, I);
2631   case Intrinsic::spv_unref_global:
2632   case Intrinsic::spv_init_global: {
2633     MachineInstr *MI = MRI->getVRegDef(I.getOperand(1).getReg());
2634     MachineInstr *Init = I.getNumExplicitOperands() > 2
2635                              ? MRI->getVRegDef(I.getOperand(2).getReg())
2636                              : nullptr;
2637     assert(MI);
2638     return selectGlobalValue(MI->getOperand(0).getReg(), *MI, Init);
2639   }
2640   case Intrinsic::spv_undef: {
2641     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpUndef))
2642                    .addDef(ResVReg)
2643                    .addUse(GR.getSPIRVTypeID(ResType));
2644     return MIB.constrainAllUses(TII, TRI, RBI);
2645   }
2646   case Intrinsic::spv_const_composite: {
2647     // If no values are attached, the composite is null constant.
2648     bool IsNull = I.getNumExplicitDefs() + 1 == I.getNumExplicitOperands();
2649     // Select a proper instruction.
2650     unsigned Opcode = SPIRV::OpConstantNull;
2651     SmallVector<Register> CompositeArgs;
2652     if (!IsNull) {
2653       Opcode = SPIRV::OpConstantComposite;
2654       if (!wrapIntoSpecConstantOp(I, CompositeArgs))
2655         return false;
2656     }
2657     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2658                    .addDef(ResVReg)
2659                    .addUse(GR.getSPIRVTypeID(ResType));
2660     // skip type MD node we already used when generated assign.type for this
2661     if (!IsNull) {
2662       for (Register OpReg : CompositeArgs)
2663         MIB.addUse(OpReg);
2664     }
2665     return MIB.constrainAllUses(TII, TRI, RBI);
2666   }
2667   case Intrinsic::spv_assign_name: {
2668     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpName));
2669     MIB.addUse(I.getOperand(I.getNumExplicitDefs() + 1).getReg());
2670     for (unsigned i = I.getNumExplicitDefs() + 2;
2671          i < I.getNumExplicitOperands(); ++i) {
2672       MIB.addImm(I.getOperand(i).getImm());
2673     }
2674     return MIB.constrainAllUses(TII, TRI, RBI);
2675   }
2676   case Intrinsic::spv_switch: {
2677     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSwitch));
2678     for (unsigned i = 1; i < I.getNumExplicitOperands(); ++i) {
2679       if (I.getOperand(i).isReg())
2680         MIB.addReg(I.getOperand(i).getReg());
2681       else if (I.getOperand(i).isCImm())
2682         addNumImm(I.getOperand(i).getCImm()->getValue(), MIB);
2683       else if (I.getOperand(i).isMBB())
2684         MIB.addMBB(I.getOperand(i).getMBB());
2685       else
2686         llvm_unreachable("Unexpected OpSwitch operand");
2687     }
2688     return MIB.constrainAllUses(TII, TRI, RBI);
2689   }
2690   case Intrinsic::spv_loop_merge:
2691   case Intrinsic::spv_selection_merge: {
2692     const auto Opcode = IID == Intrinsic::spv_selection_merge
2693                             ? SPIRV::OpSelectionMerge
2694                             : SPIRV::OpLoopMerge;
2695     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode));
2696     for (unsigned i = 1; i < I.getNumExplicitOperands(); ++i) {
2697       assert(I.getOperand(i).isMBB());
2698       MIB.addMBB(I.getOperand(i).getMBB());
2699     }
2700     MIB.addImm(SPIRV::SelectionControl::None);
2701     return MIB.constrainAllUses(TII, TRI, RBI);
2702   }
2703   case Intrinsic::spv_cmpxchg:
2704     return selectAtomicCmpXchg(ResVReg, ResType, I);
2705   case Intrinsic::spv_unreachable:
2706     return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpUnreachable))
2707         .constrainAllUses(TII, TRI, RBI);
2708   case Intrinsic::spv_alloca:
2709     return selectFrameIndex(ResVReg, ResType, I);
2710   case Intrinsic::spv_alloca_array:
2711     return selectAllocaArray(ResVReg, ResType, I);
2712   case Intrinsic::spv_assume:
2713     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_expect_assume))
2714       return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpAssumeTrueKHR))
2715           .addUse(I.getOperand(1).getReg())
2716           .constrainAllUses(TII, TRI, RBI);
2717     break;
2718   case Intrinsic::spv_expect:
2719     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_expect_assume))
2720       return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExpectKHR))
2721           .addDef(ResVReg)
2722           .addUse(GR.getSPIRVTypeID(ResType))
2723           .addUse(I.getOperand(2).getReg())
2724           .addUse(I.getOperand(3).getReg())
2725           .constrainAllUses(TII, TRI, RBI);
2726     break;
2727   case Intrinsic::arithmetic_fence:
2728     if (STI.canUseExtension(SPIRV::Extension::SPV_EXT_arithmetic_fence))
2729       return BuildMI(BB, I, I.getDebugLoc(),
2730                      TII.get(SPIRV::OpArithmeticFenceEXT))
2731           .addDef(ResVReg)
2732           .addUse(GR.getSPIRVTypeID(ResType))
2733           .addUse(I.getOperand(2).getReg())
2734           .constrainAllUses(TII, TRI, RBI);
2735     else
2736       return BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY),
2737                      ResVReg)
2738           .addUse(I.getOperand(2).getReg())
2739           .constrainAllUses(TII, TRI, RBI);
2740     break;
2741   case Intrinsic::spv_thread_id:
2742     return selectSpvThreadId(ResVReg, ResType, I);
2743   case Intrinsic::spv_fdot:
2744     return selectFloatDot(ResVReg, ResType, I);
2745   case Intrinsic::spv_udot:
2746   case Intrinsic::spv_sdot:
2747     return selectIntegerDot(ResVReg, ResType, I);
2748   case Intrinsic::spv_dot4add_i8packed:
2749     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_integer_dot_product) ||
2750         STI.isAtLeastSPIRVVer(VersionTuple(1, 6)))
2751       return selectDot4AddPacked<true>(ResVReg, ResType, I);
2752     return selectDot4AddPackedExpansion<true>(ResVReg, ResType, I);
2753   case Intrinsic::spv_dot4add_u8packed:
2754     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_integer_dot_product) ||
2755         STI.isAtLeastSPIRVVer(VersionTuple(1, 6)))
2756       return selectDot4AddPacked<false>(ResVReg, ResType, I);
2757     return selectDot4AddPackedExpansion<false>(ResVReg, ResType, I);
2758   case Intrinsic::spv_all:
2759     return selectAll(ResVReg, ResType, I);
2760   case Intrinsic::spv_any:
2761     return selectAny(ResVReg, ResType, I);
2762   case Intrinsic::spv_cross:
2763     return selectExtInst(ResVReg, ResType, I, CL::cross, GL::Cross);
2764   case Intrinsic::spv_lerp:
2765     return selectExtInst(ResVReg, ResType, I, CL::mix, GL::FMix);
2766   case Intrinsic::spv_length:
2767     return selectExtInst(ResVReg, ResType, I, CL::length, GL::Length);
2768   case Intrinsic::spv_degrees:
2769     return selectExtInst(ResVReg, ResType, I, CL::degrees, GL::Degrees);
2770   case Intrinsic::spv_frac:
2771     return selectExtInst(ResVReg, ResType, I, CL::fract, GL::Fract);
2772   case Intrinsic::spv_normalize:
2773     return selectExtInst(ResVReg, ResType, I, CL::normalize, GL::Normalize);
2774   case Intrinsic::spv_rsqrt:
2775     return selectExtInst(ResVReg, ResType, I, CL::rsqrt, GL::InverseSqrt);
2776   case Intrinsic::spv_sign:
2777     return selectSign(ResVReg, ResType, I);
2778   case Intrinsic::spv_firstbituhigh: // There is no CL equivalent of FindUMsb
2779     return selectFirstBitHigh(ResVReg, ResType, I, /*IsSigned=*/false);
2780   case Intrinsic::spv_firstbitshigh: // There is no CL equivalent of FindSMsb
2781     return selectFirstBitHigh(ResVReg, ResType, I, /*IsSigned=*/true);
2782   case Intrinsic::spv_group_memory_barrier_with_group_sync: {
2783     bool Result = true;
2784     auto MemSemConstant =
2785         buildI32Constant(SPIRV::MemorySemantics::SequentiallyConsistent, I);
2786     Register MemSemReg = MemSemConstant.first;
2787     Result &= MemSemConstant.second;
2788     auto ScopeConstant = buildI32Constant(SPIRV::Scope::Workgroup, I);
2789     Register ScopeReg = ScopeConstant.first;
2790     Result &= ScopeConstant.second;
2791     MachineBasicBlock &BB = *I.getParent();
2792     return Result &&
2793            BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpControlBarrier))
2794                .addUse(ScopeReg)
2795                .addUse(ScopeReg)
2796                .addUse(MemSemReg)
2797                .constrainAllUses(TII, TRI, RBI);
2798   }
2799   case Intrinsic::spv_lifetime_start:
2800   case Intrinsic::spv_lifetime_end: {
2801     unsigned Op = IID == Intrinsic::spv_lifetime_start ? SPIRV::OpLifetimeStart
2802                                                        : SPIRV::OpLifetimeStop;
2803     int64_t Size = I.getOperand(I.getNumExplicitDefs() + 1).getImm();
2804     Register PtrReg = I.getOperand(I.getNumExplicitDefs() + 2).getReg();
2805     if (Size == -1)
2806       Size = 0;
2807     return BuildMI(BB, I, I.getDebugLoc(), TII.get(Op))
2808         .addUse(PtrReg)
2809         .addImm(Size)
2810         .constrainAllUses(TII, TRI, RBI);
2811   }
2812   case Intrinsic::spv_saturate:
2813     return selectSaturate(ResVReg, ResType, I);
2814   case Intrinsic::spv_nclamp:
2815     return selectExtInst(ResVReg, ResType, I, CL::fclamp, GL::NClamp);
2816   case Intrinsic::spv_uclamp:
2817     return selectExtInst(ResVReg, ResType, I, CL::u_clamp, GL::UClamp);
2818   case Intrinsic::spv_sclamp:
2819     return selectExtInst(ResVReg, ResType, I, CL::s_clamp, GL::SClamp);
2820   case Intrinsic::spv_wave_active_countbits:
2821     return selectWaveActiveCountBits(ResVReg, ResType, I);
2822   case Intrinsic::spv_wave_is_first_lane: {
2823     SPIRVType *IntTy = GR.getOrCreateSPIRVIntegerType(32, I, TII);
2824     return BuildMI(BB, I, I.getDebugLoc(),
2825                    TII.get(SPIRV::OpGroupNonUniformElect))
2826         .addDef(ResVReg)
2827         .addUse(GR.getSPIRVTypeID(ResType))
2828         .addUse(GR.getOrCreateConstInt(3, I, IntTy, TII));
2829   }
2830   case Intrinsic::spv_wave_readlane:
2831     return selectWaveReadLaneAt(ResVReg, ResType, I);
2832   case Intrinsic::spv_step:
2833     return selectExtInst(ResVReg, ResType, I, CL::step, GL::Step);
2834   case Intrinsic::spv_radians:
2835     return selectExtInst(ResVReg, ResType, I, CL::radians, GL::Radians);
2836   // Discard intrinsics which we do not expect to actually represent code after
2837   // lowering or intrinsics which are not implemented but should not crash when
2838   // found in a customer's LLVM IR input.
2839   case Intrinsic::instrprof_increment:
2840   case Intrinsic::instrprof_increment_step:
2841   case Intrinsic::instrprof_value_profile:
2842     break;
2843   // Discard internal intrinsics.
2844   case Intrinsic::spv_value_md:
2845     break;
2846   case Intrinsic::spv_handle_fromBinding: {
2847     return selectHandleFromBinding(ResVReg, ResType, I);
2848   }
2849   default: {
2850     std::string DiagMsg;
2851     raw_string_ostream OS(DiagMsg);
2852     I.print(OS);
2853     DiagMsg = "Intrinsic selection not implemented: " + DiagMsg;
2854     report_fatal_error(DiagMsg.c_str(), false);
2855   }
2856   }
2857   return true;
2858 }
2859 
2860 bool SPIRVInstructionSelector::selectHandleFromBinding(Register &ResVReg,
2861                                                        const SPIRVType *ResType,
2862                                                        MachineInstr &I) const {
2863 
2864   uint32_t Set = foldImm(I.getOperand(2), MRI);
2865   uint32_t Binding = foldImm(I.getOperand(3), MRI);
2866   uint32_t ArraySize = foldImm(I.getOperand(4), MRI);
2867   Register IndexReg = I.getOperand(5).getReg();
2868   bool IsNonUniform = ArraySize > 1 && foldImm(I.getOperand(6), MRI);
2869 
2870   MachineIRBuilder MIRBuilder(I);
2871   Register VarReg = buildPointerToResource(ResType, Set, Binding, ArraySize,
2872                                            IndexReg, IsNonUniform, MIRBuilder);
2873 
2874   if (IsNonUniform)
2875     buildOpDecorate(ResVReg, I, TII, SPIRV::Decoration::NonUniformEXT, {});
2876 
2877   // TODO: For now we assume the resource is an image, which needs to be
2878   // loaded to get the handle. That will not be true for storage buffers.
2879   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
2880       .addDef(ResVReg)
2881       .addUse(GR.getSPIRVTypeID(ResType))
2882       .addUse(VarReg)
2883       .constrainAllUses(TII, TRI, RBI);
2884 }
2885 
2886 Register SPIRVInstructionSelector::buildPointerToResource(
2887     const SPIRVType *ResType, uint32_t Set, uint32_t Binding,
2888     uint32_t ArraySize, Register IndexReg, bool IsNonUniform,
2889     MachineIRBuilder MIRBuilder) const {
2890   if (ArraySize == 1)
2891     return GR.getOrCreateGlobalVariableWithBinding(ResType, Set, Binding,
2892                                                    MIRBuilder);
2893 
2894   const SPIRVType *VarType = GR.getOrCreateSPIRVArrayType(
2895       ResType, ArraySize, *MIRBuilder.getInsertPt(), TII);
2896   Register VarReg = GR.getOrCreateGlobalVariableWithBinding(
2897       VarType, Set, Binding, MIRBuilder);
2898 
2899   SPIRVType *ResPointerType = GR.getOrCreateSPIRVPointerType(
2900       ResType, MIRBuilder, SPIRV::StorageClass::UniformConstant);
2901 
2902   Register AcReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2903   if (IsNonUniform) {
2904     // It is unclear which value needs to be marked an non-uniform, so both
2905     // the index and the access changed are decorated as non-uniform.
2906     buildOpDecorate(IndexReg, MIRBuilder, SPIRV::Decoration::NonUniformEXT, {});
2907     buildOpDecorate(AcReg, MIRBuilder, SPIRV::Decoration::NonUniformEXT, {});
2908   }
2909 
2910   MIRBuilder.buildInstr(SPIRV::OpAccessChain)
2911       .addDef(AcReg)
2912       .addUse(GR.getSPIRVTypeID(ResPointerType))
2913       .addUse(VarReg)
2914       .addUse(IndexReg);
2915 
2916   return AcReg;
2917 }
2918 
2919 bool SPIRVInstructionSelector::selectFirstBitHigh16(Register ResVReg,
2920                                                     const SPIRVType *ResType,
2921                                                     MachineInstr &I,
2922                                                     bool IsSigned) const {
2923   unsigned Opcode = IsSigned ? SPIRV::OpSConvert : SPIRV::OpUConvert;
2924   // zero or sign extend
2925   Register ExtReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
2926   bool Result =
2927       selectUnOpWithSrc(ExtReg, ResType, I, I.getOperand(2).getReg(), Opcode);
2928   return Result && selectFirstBitHigh32(ResVReg, ResType, I, ExtReg, IsSigned);
2929 }
2930 
2931 bool SPIRVInstructionSelector::selectFirstBitHigh32(Register ResVReg,
2932                                                     const SPIRVType *ResType,
2933                                                     MachineInstr &I,
2934                                                     Register SrcReg,
2935                                                     bool IsSigned) const {
2936   unsigned Opcode = IsSigned ? GL::FindSMsb : GL::FindUMsb;
2937   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
2938       .addDef(ResVReg)
2939       .addUse(GR.getSPIRVTypeID(ResType))
2940       .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
2941       .addImm(Opcode)
2942       .addUse(SrcReg)
2943       .constrainAllUses(TII, TRI, RBI);
2944 }
2945 
2946 bool SPIRVInstructionSelector::selectFirstBitHigh64(Register ResVReg,
2947                                                     const SPIRVType *ResType,
2948                                                     MachineInstr &I,
2949                                                     bool IsSigned) const {
2950   Register OpReg = I.getOperand(2).getReg();
2951   // 1. split our int64 into 2 pieces using a bitcast
2952   unsigned count = GR.getScalarOrVectorComponentCount(ResType);
2953   SPIRVType *baseType = GR.retrieveScalarOrVectorIntType(ResType);
2954   MachineIRBuilder MIRBuilder(I);
2955   SPIRVType *postCastT =
2956       GR.getOrCreateSPIRVVectorType(baseType, 2 * count, MIRBuilder);
2957   Register bitcastReg = MRI->createVirtualRegister(GR.getRegClass(postCastT));
2958   bool Result =
2959       selectUnOpWithSrc(bitcastReg, postCastT, I, OpReg, SPIRV::OpBitcast);
2960 
2961   // 2. call firstbithigh
2962   Register FBHReg = MRI->createVirtualRegister(GR.getRegClass(postCastT));
2963   Result &= selectFirstBitHigh32(FBHReg, postCastT, I, bitcastReg, IsSigned);
2964 
2965   // 3. split result vector into high bits and low bits
2966   Register HighReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
2967   Register LowReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
2968 
2969   bool ZeroAsNull = STI.isOpenCLEnv();
2970   bool isScalarRes = ResType->getOpcode() != SPIRV::OpTypeVector;
2971   if (isScalarRes) {
2972     // if scalar do a vector extract
2973     Result &= selectNAryOpWithSrcs(
2974         HighReg, ResType, I,
2975         {FBHReg, GR.getOrCreateConstInt(0, I, ResType, TII, ZeroAsNull)},
2976         SPIRV::OpVectorExtractDynamic);
2977     Result &= selectNAryOpWithSrcs(
2978         LowReg, ResType, I,
2979         {FBHReg, GR.getOrCreateConstInt(1, I, ResType, TII, ZeroAsNull)},
2980         SPIRV::OpVectorExtractDynamic);
2981   } else { // vector case do a shufflevector
2982     auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
2983                        TII.get(SPIRV::OpVectorShuffle))
2984                    .addDef(HighReg)
2985                    .addUse(GR.getSPIRVTypeID(ResType))
2986                    .addUse(FBHReg)
2987                    .addUse(FBHReg);
2988     // ^^ this vector will not be selected from; could be empty
2989     unsigned j;
2990     for (j = 0; j < count * 2; j += 2) {
2991       MIB.addImm(j);
2992     }
2993     Result &= MIB.constrainAllUses(TII, TRI, RBI);
2994 
2995     // get low bits
2996     MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
2997                   TII.get(SPIRV::OpVectorShuffle))
2998               .addDef(LowReg)
2999               .addUse(GR.getSPIRVTypeID(ResType))
3000               .addUse(FBHReg)
3001               .addUse(FBHReg);
3002     // ^^ this vector will not be selected from; could be empty
3003     for (j = 1; j < count * 2; j += 2) {
3004       MIB.addImm(j);
3005     }
3006     Result &= MIB.constrainAllUses(TII, TRI, RBI);
3007   }
3008 
3009   // 4. check if result of each top 32 bits is == -1
3010   SPIRVType *BoolType = GR.getOrCreateSPIRVBoolType(I, TII);
3011   Register NegOneReg;
3012   Register Reg0;
3013   Register Reg32;
3014   unsigned selectOp;
3015   unsigned addOp;
3016   if (isScalarRes) {
3017     NegOneReg =
3018         GR.getOrCreateConstInt((unsigned)-1, I, ResType, TII, ZeroAsNull);
3019     Reg0 = GR.getOrCreateConstInt(0, I, ResType, TII, ZeroAsNull);
3020     Reg32 = GR.getOrCreateConstInt(32, I, ResType, TII, ZeroAsNull);
3021     selectOp = SPIRV::OpSelectSISCond;
3022     addOp = SPIRV::OpIAddS;
3023   } else {
3024     BoolType = GR.getOrCreateSPIRVVectorType(BoolType, count, MIRBuilder);
3025     NegOneReg =
3026         GR.getOrCreateConstVector((unsigned)-1, I, ResType, TII, ZeroAsNull);
3027     Reg0 = GR.getOrCreateConstVector(0, I, ResType, TII, ZeroAsNull);
3028     Reg32 = GR.getOrCreateConstVector(32, I, ResType, TII, ZeroAsNull);
3029     selectOp = SPIRV::OpSelectVIVCond;
3030     addOp = SPIRV::OpIAddV;
3031   }
3032 
3033   // check if the high bits are == -1; true if -1
3034   Register BReg = MRI->createVirtualRegister(GR.getRegClass(BoolType));
3035   Result &= selectNAryOpWithSrcs(BReg, BoolType, I, {HighReg, NegOneReg},
3036                                  SPIRV::OpIEqual);
3037 
3038   // Select low bits if true in BReg, otherwise high bits
3039   Register TmpReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
3040   Result &= selectNAryOpWithSrcs(TmpReg, ResType, I, {BReg, LowReg, HighReg},
3041                                  selectOp);
3042 
3043   // Add 32 for high bits, 0 for low bits
3044   Register ValReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
3045   Result &=
3046       selectNAryOpWithSrcs(ValReg, ResType, I, {BReg, Reg0, Reg32}, selectOp);
3047 
3048   return Result &&
3049          selectNAryOpWithSrcs(ResVReg, ResType, I, {ValReg, TmpReg}, addOp);
3050 }
3051 
3052 bool SPIRVInstructionSelector::selectFirstBitHigh(Register ResVReg,
3053                                                   const SPIRVType *ResType,
3054                                                   MachineInstr &I,
3055                                                   bool IsSigned) const {
3056   // FindUMsb and FindSMsb intrinsics only support 32 bit integers
3057   Register OpReg = I.getOperand(2).getReg();
3058   SPIRVType *OpType = GR.getSPIRVTypeForVReg(OpReg);
3059 
3060   switch (GR.getScalarOrVectorBitWidth(OpType)) {
3061   case 16:
3062     return selectFirstBitHigh16(ResVReg, ResType, I, IsSigned);
3063   case 32:
3064     return selectFirstBitHigh32(ResVReg, ResType, I, OpReg, IsSigned);
3065   case 64:
3066     return selectFirstBitHigh64(ResVReg, ResType, I, IsSigned);
3067   default:
3068     report_fatal_error(
3069         "spv_firstbituhigh and spv_firstbitshigh only support 16,32,64 bits.");
3070   }
3071 }
3072 
3073 bool SPIRVInstructionSelector::selectAllocaArray(Register ResVReg,
3074                                                  const SPIRVType *ResType,
3075                                                  MachineInstr &I) const {
3076   // there was an allocation size parameter to the allocation instruction
3077   // that is not 1
3078   MachineBasicBlock &BB = *I.getParent();
3079   return BuildMI(BB, I, I.getDebugLoc(),
3080                  TII.get(SPIRV::OpVariableLengthArrayINTEL))
3081       .addDef(ResVReg)
3082       .addUse(GR.getSPIRVTypeID(ResType))
3083       .addUse(I.getOperand(2).getReg())
3084       .constrainAllUses(TII, TRI, RBI);
3085 }
3086 
3087 bool SPIRVInstructionSelector::selectFrameIndex(Register ResVReg,
3088                                                 const SPIRVType *ResType,
3089                                                 MachineInstr &I) const {
3090   // Change order of instructions if needed: all OpVariable instructions in a
3091   // function must be the first instructions in the first block
3092   MachineFunction *MF = I.getParent()->getParent();
3093   MachineBasicBlock *MBB = &MF->front();
3094   auto It = MBB->SkipPHIsAndLabels(MBB->begin()), E = MBB->end();
3095   bool IsHeader = false;
3096   unsigned Opcode;
3097   for (; It != E && It != I; ++It) {
3098     Opcode = It->getOpcode();
3099     if (Opcode == SPIRV::OpFunction || Opcode == SPIRV::OpFunctionParameter) {
3100       IsHeader = true;
3101     } else if (IsHeader &&
3102                !(Opcode == SPIRV::ASSIGN_TYPE || Opcode == SPIRV::OpLabel)) {
3103       ++It;
3104       break;
3105     }
3106   }
3107   return BuildMI(*MBB, It, It->getDebugLoc(), TII.get(SPIRV::OpVariable))
3108       .addDef(ResVReg)
3109       .addUse(GR.getSPIRVTypeID(ResType))
3110       .addImm(static_cast<uint32_t>(SPIRV::StorageClass::Function))
3111       .constrainAllUses(TII, TRI, RBI);
3112 }
3113 
3114 bool SPIRVInstructionSelector::selectBranch(MachineInstr &I) const {
3115   // InstructionSelector walks backwards through the instructions. We can use
3116   // both a G_BR and a G_BRCOND to create an OpBranchConditional. We hit G_BR
3117   // first, so can generate an OpBranchConditional here. If there is no
3118   // G_BRCOND, we just use OpBranch for a regular unconditional branch.
3119   const MachineInstr *PrevI = I.getPrevNode();
3120   MachineBasicBlock &MBB = *I.getParent();
3121   if (PrevI != nullptr && PrevI->getOpcode() == TargetOpcode::G_BRCOND) {
3122     return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranchConditional))
3123         .addUse(PrevI->getOperand(0).getReg())
3124         .addMBB(PrevI->getOperand(1).getMBB())
3125         .addMBB(I.getOperand(0).getMBB())
3126         .constrainAllUses(TII, TRI, RBI);
3127   }
3128   return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranch))
3129       .addMBB(I.getOperand(0).getMBB())
3130       .constrainAllUses(TII, TRI, RBI);
3131 }
3132 
3133 bool SPIRVInstructionSelector::selectBranchCond(MachineInstr &I) const {
3134   // InstructionSelector walks backwards through the instructions. For an
3135   // explicit conditional branch with no fallthrough, we use both a G_BR and a
3136   // G_BRCOND to create an OpBranchConditional. We should hit G_BR first, and
3137   // generate the OpBranchConditional in selectBranch above.
3138   //
3139   // If an OpBranchConditional has been generated, we simply return, as the work
3140   // is alread done. If there is no OpBranchConditional, LLVM must be relying on
3141   // implicit fallthrough to the next basic block, so we need to create an
3142   // OpBranchConditional with an explicit "false" argument pointing to the next
3143   // basic block that LLVM would fall through to.
3144   const MachineInstr *NextI = I.getNextNode();
3145   // Check if this has already been successfully selected.
3146   if (NextI != nullptr && NextI->getOpcode() == SPIRV::OpBranchConditional)
3147     return true;
3148   // Must be relying on implicit block fallthrough, so generate an
3149   // OpBranchConditional with the "next" basic block as the "false" target.
3150   MachineBasicBlock &MBB = *I.getParent();
3151   unsigned NextMBBNum = MBB.getNextNode()->getNumber();
3152   MachineBasicBlock *NextMBB = I.getMF()->getBlockNumbered(NextMBBNum);
3153   return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranchConditional))
3154       .addUse(I.getOperand(0).getReg())
3155       .addMBB(I.getOperand(1).getMBB())
3156       .addMBB(NextMBB)
3157       .constrainAllUses(TII, TRI, RBI);
3158 }
3159 
3160 bool SPIRVInstructionSelector::selectPhi(Register ResVReg,
3161                                          const SPIRVType *ResType,
3162                                          MachineInstr &I) const {
3163   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpPhi))
3164                  .addDef(ResVReg)
3165                  .addUse(GR.getSPIRVTypeID(ResType));
3166   const unsigned NumOps = I.getNumOperands();
3167   for (unsigned i = 1; i < NumOps; i += 2) {
3168     MIB.addUse(I.getOperand(i + 0).getReg());
3169     MIB.addMBB(I.getOperand(i + 1).getMBB());
3170   }
3171   return MIB.constrainAllUses(TII, TRI, RBI);
3172 }
3173 
3174 bool SPIRVInstructionSelector::selectGlobalValue(
3175     Register ResVReg, MachineInstr &I, const MachineInstr *Init) const {
3176   // FIXME: don't use MachineIRBuilder here, replace it with BuildMI.
3177   MachineIRBuilder MIRBuilder(I);
3178   const GlobalValue *GV = I.getOperand(1).getGlobal();
3179   Type *GVType = toTypedPointer(GR.getDeducedGlobalValueType(GV));
3180   SPIRVType *PointerBaseType;
3181   if (GVType->isArrayTy()) {
3182     SPIRVType *ArrayElementType =
3183         GR.getOrCreateSPIRVType(GVType->getArrayElementType(), MIRBuilder,
3184                                 SPIRV::AccessQualifier::ReadWrite, false);
3185     PointerBaseType = GR.getOrCreateSPIRVArrayType(
3186         ArrayElementType, GVType->getArrayNumElements(), I, TII);
3187   } else {
3188     PointerBaseType = GR.getOrCreateSPIRVType(
3189         GVType, MIRBuilder, SPIRV::AccessQualifier::ReadWrite, false);
3190   }
3191   SPIRVType *ResType = GR.getOrCreateSPIRVPointerType(
3192       PointerBaseType, I, TII,
3193       addressSpaceToStorageClass(GV->getAddressSpace(), STI));
3194 
3195   std::string GlobalIdent;
3196   if (!GV->hasName()) {
3197     unsigned &ID = UnnamedGlobalIDs[GV];
3198     if (ID == 0)
3199       ID = UnnamedGlobalIDs.size();
3200     GlobalIdent = "__unnamed_" + Twine(ID).str();
3201   } else {
3202     GlobalIdent = GV->getGlobalIdentifier();
3203   }
3204 
3205   // Behaviour of functions as operands depends on availability of the
3206   // corresponding extension (SPV_INTEL_function_pointers):
3207   // - If there is an extension to operate with functions as operands:
3208   // We create a proper constant operand and evaluate a correct type for a
3209   // function pointer.
3210   // - Without the required extension:
3211   // We have functions as operands in tests with blocks of instruction e.g. in
3212   // transcoding/global_block.ll. These operands are not used and should be
3213   // substituted by zero constants. Their type is expected to be always
3214   // OpTypePointer Function %uchar.
3215   if (isa<Function>(GV)) {
3216     const Constant *ConstVal = GV;
3217     MachineBasicBlock &BB = *I.getParent();
3218     Register NewReg = GR.find(ConstVal, GR.CurMF);
3219     if (!NewReg.isValid()) {
3220       Register NewReg = ResVReg;
3221       GR.add(ConstVal, GR.CurMF, NewReg);
3222       const Function *GVFun =
3223           STI.canUseExtension(SPIRV::Extension::SPV_INTEL_function_pointers)
3224               ? dyn_cast<Function>(GV)
3225               : nullptr;
3226       if (GVFun) {
3227         // References to a function via function pointers generate virtual
3228         // registers without a definition. We will resolve it later, during
3229         // module analysis stage.
3230         MachineRegisterInfo *MRI = MIRBuilder.getMRI();
3231         Register FuncVReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
3232         MRI->setRegClass(FuncVReg, &SPIRV::iIDRegClass);
3233         MachineInstrBuilder MB =
3234             BuildMI(BB, I, I.getDebugLoc(),
3235                     TII.get(SPIRV::OpConstantFunctionPointerINTEL))
3236                 .addDef(NewReg)
3237                 .addUse(GR.getSPIRVTypeID(ResType))
3238                 .addUse(FuncVReg);
3239         // mapping the function pointer to the used Function
3240         GR.recordFunctionPointer(&MB.getInstr()->getOperand(2), GVFun);
3241         return MB.constrainAllUses(TII, TRI, RBI);
3242       }
3243       return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
3244           .addDef(NewReg)
3245           .addUse(GR.getSPIRVTypeID(ResType))
3246           .constrainAllUses(TII, TRI, RBI);
3247     }
3248     assert(NewReg != ResVReg);
3249     return BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY))
3250         .addDef(ResVReg)
3251         .addUse(NewReg)
3252         .constrainAllUses(TII, TRI, RBI);
3253   }
3254   auto GlobalVar = cast<GlobalVariable>(GV);
3255   assert(GlobalVar->getName() != "llvm.global.annotations");
3256 
3257   bool HasInit = GlobalVar->hasInitializer() &&
3258                  !isa<UndefValue>(GlobalVar->getInitializer());
3259   // Skip empty declaration for GVs with initilaizers till we get the decl with
3260   // passed initializer.
3261   if (HasInit && !Init)
3262     return true;
3263 
3264   unsigned AddrSpace = GV->getAddressSpace();
3265   SPIRV::StorageClass::StorageClass Storage =
3266       addressSpaceToStorageClass(AddrSpace, STI);
3267   bool HasLnkTy = GV->getLinkage() != GlobalValue::InternalLinkage &&
3268                   Storage != SPIRV::StorageClass::Function;
3269   SPIRV::LinkageType::LinkageType LnkType =
3270       (GV->isDeclaration() || GV->hasAvailableExternallyLinkage())
3271           ? SPIRV::LinkageType::Import
3272           : (GV->getLinkage() == GlobalValue::LinkOnceODRLinkage &&
3273                      STI.canUseExtension(SPIRV::Extension::SPV_KHR_linkonce_odr)
3274                  ? SPIRV::LinkageType::LinkOnceODR
3275                  : SPIRV::LinkageType::Export);
3276 
3277   Register Reg = GR.buildGlobalVariable(ResVReg, ResType, GlobalIdent, GV,
3278                                         Storage, Init, GlobalVar->isConstant(),
3279                                         HasLnkTy, LnkType, MIRBuilder, true);
3280   return Reg.isValid();
3281 }
3282 
3283 bool SPIRVInstructionSelector::selectLog10(Register ResVReg,
3284                                            const SPIRVType *ResType,
3285                                            MachineInstr &I) const {
3286   if (STI.canUseExtInstSet(SPIRV::InstructionSet::OpenCL_std)) {
3287     return selectExtInst(ResVReg, ResType, I, CL::log10);
3288   }
3289 
3290   // There is no log10 instruction in the GLSL Extended Instruction set, so it
3291   // is implemented as:
3292   // log10(x) = log2(x) * (1 / log2(10))
3293   //          = log2(x) * 0.30103
3294 
3295   MachineIRBuilder MIRBuilder(I);
3296   MachineBasicBlock &BB = *I.getParent();
3297 
3298   // Build log2(x).
3299   Register VarReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
3300   bool Result =
3301       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
3302           .addDef(VarReg)
3303           .addUse(GR.getSPIRVTypeID(ResType))
3304           .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
3305           .addImm(GL::Log2)
3306           .add(I.getOperand(1))
3307           .constrainAllUses(TII, TRI, RBI);
3308 
3309   // Build 0.30103.
3310   assert(ResType->getOpcode() == SPIRV::OpTypeVector ||
3311          ResType->getOpcode() == SPIRV::OpTypeFloat);
3312   // TODO: Add matrix implementation once supported by the HLSL frontend.
3313   const SPIRVType *SpirvScalarType =
3314       ResType->getOpcode() == SPIRV::OpTypeVector
3315           ? GR.getSPIRVTypeForVReg(ResType->getOperand(1).getReg())
3316           : ResType;
3317   Register ScaleReg =
3318       GR.buildConstantFP(APFloat(0.30103f), MIRBuilder, SpirvScalarType);
3319 
3320   // Multiply log2(x) by 0.30103 to get log10(x) result.
3321   auto Opcode = ResType->getOpcode() == SPIRV::OpTypeVector
3322                     ? SPIRV::OpVectorTimesScalar
3323                     : SPIRV::OpFMulS;
3324   return Result && BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
3325                        .addDef(ResVReg)
3326                        .addUse(GR.getSPIRVTypeID(ResType))
3327                        .addUse(VarReg)
3328                        .addUse(ScaleReg)
3329                        .constrainAllUses(TII, TRI, RBI);
3330 }
3331 
3332 bool SPIRVInstructionSelector::selectSpvThreadId(Register ResVReg,
3333                                                  const SPIRVType *ResType,
3334                                                  MachineInstr &I) const {
3335   // DX intrinsic: @llvm.dx.thread.id(i32)
3336   // ID  Name      Description
3337   // 93  ThreadId  reads the thread ID
3338 
3339   MachineIRBuilder MIRBuilder(I);
3340   const SPIRVType *U32Type = GR.getOrCreateSPIRVIntegerType(32, MIRBuilder);
3341   const SPIRVType *Vec3Ty =
3342       GR.getOrCreateSPIRVVectorType(U32Type, 3, MIRBuilder);
3343   const SPIRVType *PtrType = GR.getOrCreateSPIRVPointerType(
3344       Vec3Ty, MIRBuilder, SPIRV::StorageClass::Input);
3345 
3346   // Create new register for GlobalInvocationID builtin variable.
3347   Register NewRegister =
3348       MIRBuilder.getMRI()->createVirtualRegister(&SPIRV::iIDRegClass);
3349   MIRBuilder.getMRI()->setType(NewRegister, LLT::pointer(0, 64));
3350   GR.assignSPIRVTypeToVReg(PtrType, NewRegister, MIRBuilder.getMF());
3351 
3352   // Build GlobalInvocationID global variable with the necessary decorations.
3353   Register Variable = GR.buildGlobalVariable(
3354       NewRegister, PtrType,
3355       getLinkStringForBuiltIn(SPIRV::BuiltIn::GlobalInvocationId), nullptr,
3356       SPIRV::StorageClass::Input, nullptr, true, true,
3357       SPIRV::LinkageType::Import, MIRBuilder, false);
3358 
3359   // Create new register for loading value.
3360   MachineRegisterInfo *MRI = MIRBuilder.getMRI();
3361   Register LoadedRegister = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
3362   MIRBuilder.getMRI()->setType(LoadedRegister, LLT::pointer(0, 64));
3363   GR.assignSPIRVTypeToVReg(Vec3Ty, LoadedRegister, MIRBuilder.getMF());
3364 
3365   // Load v3uint value from the global variable.
3366   bool Result =
3367       BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
3368           .addDef(LoadedRegister)
3369           .addUse(GR.getSPIRVTypeID(Vec3Ty))
3370           .addUse(Variable);
3371 
3372   // Get Thread ID index. Expecting operand is a constant immediate value,
3373   // wrapped in a type assignment.
3374   assert(I.getOperand(2).isReg());
3375   const uint32_t ThreadId = foldImm(I.getOperand(2), MRI);
3376 
3377   // Extract the thread ID from the loaded vector value.
3378   MachineBasicBlock &BB = *I.getParent();
3379   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
3380                  .addDef(ResVReg)
3381                  .addUse(GR.getSPIRVTypeID(ResType))
3382                  .addUse(LoadedRegister)
3383                  .addImm(ThreadId);
3384   return Result && MIB.constrainAllUses(TII, TRI, RBI);
3385 }
3386 
3387 namespace llvm {
3388 InstructionSelector *
3389 createSPIRVInstructionSelector(const SPIRVTargetMachine &TM,
3390                                const SPIRVSubtarget &Subtarget,
3391                                const RegisterBankInfo &RBI) {
3392   return new SPIRVInstructionSelector(TM, Subtarget, RBI);
3393 }
3394 } // namespace llvm
3395