xref: /llvm-project/llvm/lib/Target/SPIRV/SPIRVInstructionSelector.cpp (revision 2647505027d8c01fc920b04aced8cec742a4b2ed)
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 selectGlobalValue(Register ResVReg, MachineInstr &I,
96                          const MachineInstr *Init = nullptr) const;
97 
98   bool selectUnOpWithSrc(Register ResVReg, const SPIRVType *ResType,
99                          MachineInstr &I, Register SrcReg,
100                          unsigned Opcode) const;
101   bool selectUnOp(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
102                   unsigned Opcode) const;
103 
104   bool selectBitcast(Register ResVReg, const SPIRVType *ResType,
105                      MachineInstr &I) const;
106 
107   bool selectLoad(Register ResVReg, const SPIRVType *ResType,
108                   MachineInstr &I) const;
109   bool selectStore(MachineInstr &I) const;
110 
111   bool selectStackSave(Register ResVReg, const SPIRVType *ResType,
112                        MachineInstr &I) const;
113   bool selectStackRestore(MachineInstr &I) const;
114 
115   bool selectMemOperation(Register ResVReg, MachineInstr &I) const;
116 
117   bool selectAtomicRMW(Register ResVReg, const SPIRVType *ResType,
118                        MachineInstr &I, unsigned NewOpcode,
119                        unsigned NegateOpcode = 0) const;
120 
121   bool selectAtomicCmpXchg(Register ResVReg, const SPIRVType *ResType,
122                            MachineInstr &I) const;
123 
124   bool selectFence(MachineInstr &I) const;
125 
126   bool selectAddrSpaceCast(Register ResVReg, const SPIRVType *ResType,
127                            MachineInstr &I) const;
128 
129   bool selectAnyOrAll(Register ResVReg, const SPIRVType *ResType,
130                       MachineInstr &I, unsigned OpType) const;
131 
132   bool selectAll(Register ResVReg, const SPIRVType *ResType,
133                  MachineInstr &I) const;
134 
135   bool selectAny(Register ResVReg, const SPIRVType *ResType,
136                  MachineInstr &I) const;
137 
138   bool selectBitreverse(Register ResVReg, const SPIRVType *ResType,
139                         MachineInstr &I) const;
140 
141   bool selectBuildVector(Register ResVReg, const SPIRVType *ResType,
142                          MachineInstr &I) const;
143   bool selectSplatVector(Register ResVReg, const SPIRVType *ResType,
144                          MachineInstr &I) const;
145 
146   bool selectCmp(Register ResVReg, const SPIRVType *ResType,
147                  unsigned comparisonOpcode, MachineInstr &I) const;
148   bool selectCross(Register ResVReg, const SPIRVType *ResType,
149                    MachineInstr &I) const;
150   bool selectICmp(Register ResVReg, const SPIRVType *ResType,
151                   MachineInstr &I) const;
152   bool selectFCmp(Register ResVReg, const SPIRVType *ResType,
153                   MachineInstr &I) const;
154 
155   bool selectSign(Register ResVReg, const SPIRVType *ResType,
156                   MachineInstr &I) const;
157 
158   bool selectFloatDot(Register ResVReg, const SPIRVType *ResType,
159                       MachineInstr &I) const;
160 
161   bool selectOverflowArith(Register ResVReg, const SPIRVType *ResType,
162                            MachineInstr &I, unsigned Opcode) const;
163 
164   bool selectIntegerDot(Register ResVReg, const SPIRVType *ResType,
165                         MachineInstr &I) const;
166 
167   void renderImm32(MachineInstrBuilder &MIB, const MachineInstr &I,
168                    int OpIdx) const;
169   void renderFImm64(MachineInstrBuilder &MIB, const MachineInstr &I,
170                     int OpIdx) const;
171 
172   bool selectConst(Register ResVReg, const SPIRVType *ResType, const APInt &Imm,
173                    MachineInstr &I) const;
174 
175   bool selectSelect(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
176                     bool IsSigned) const;
177   bool selectIToF(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
178                   bool IsSigned, unsigned Opcode) const;
179   bool selectExt(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
180                  bool IsSigned) const;
181 
182   bool selectTrunc(Register ResVReg, const SPIRVType *ResType,
183                    MachineInstr &I) const;
184 
185   bool selectIntToBool(Register IntReg, Register ResVReg, MachineInstr &I,
186                        const SPIRVType *intTy, const SPIRVType *boolTy) const;
187 
188   bool selectOpUndef(Register ResVReg, const SPIRVType *ResType,
189                      MachineInstr &I) const;
190   bool selectFreeze(Register ResVReg, const SPIRVType *ResType,
191                     MachineInstr &I) const;
192   bool selectIntrinsic(Register ResVReg, const SPIRVType *ResType,
193                        MachineInstr &I) const;
194   bool selectExtractVal(Register ResVReg, const SPIRVType *ResType,
195                         MachineInstr &I) const;
196   bool selectInsertVal(Register ResVReg, const SPIRVType *ResType,
197                        MachineInstr &I) const;
198   bool selectExtractElt(Register ResVReg, const SPIRVType *ResType,
199                         MachineInstr &I) const;
200   bool selectInsertElt(Register ResVReg, const SPIRVType *ResType,
201                        MachineInstr &I) const;
202   bool selectGEP(Register ResVReg, const SPIRVType *ResType,
203                  MachineInstr &I) const;
204 
205   bool selectFrameIndex(Register ResVReg, const SPIRVType *ResType,
206                         MachineInstr &I) const;
207   bool selectAllocaArray(Register ResVReg, const SPIRVType *ResType,
208                          MachineInstr &I) const;
209 
210   bool selectBranch(MachineInstr &I) const;
211   bool selectBranchCond(MachineInstr &I) const;
212 
213   bool selectPhi(Register ResVReg, const SPIRVType *ResType,
214                  MachineInstr &I) const;
215 
216   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
217                      MachineInstr &I, CL::OpenCLExtInst CLInst) const;
218   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
219                      MachineInstr &I, CL::OpenCLExtInst CLInst,
220                      GL::GLSLExtInst GLInst) const;
221   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
222                      MachineInstr &I, const ExtInstList &ExtInsts) const;
223 
224   bool selectLog10(Register ResVReg, const SPIRVType *ResType,
225                    MachineInstr &I) const;
226 
227   bool selectSaturate(Register ResVReg, const SPIRVType *ResType,
228                       MachineInstr &I) const;
229 
230   bool selectSpvThreadId(Register ResVReg, const SPIRVType *ResType,
231                          MachineInstr &I) const;
232 
233   bool selectUnmergeValues(MachineInstr &I) const;
234 
235   void selectHandleFromBinding(Register &ResVReg, const SPIRVType *ResType,
236                                MachineInstr &I) const;
237 
238   // Utilities
239   Register buildI32Constant(uint32_t Val, MachineInstr &I,
240                             const SPIRVType *ResType = nullptr) const;
241 
242   Register buildZerosVal(const SPIRVType *ResType, MachineInstr &I) const;
243   Register buildZerosValF(const SPIRVType *ResType, MachineInstr &I) const;
244   Register buildOnesVal(bool AllOnes, const SPIRVType *ResType,
245                         MachineInstr &I) const;
246   Register buildOnesValF(const SPIRVType *ResType, MachineInstr &I) const;
247 
248   bool wrapIntoSpecConstantOp(MachineInstr &I,
249                               SmallVector<Register> &CompositeArgs) const;
250 
251   Register getUcharPtrTypeReg(MachineInstr &I,
252                               SPIRV::StorageClass::StorageClass SC) const;
253   MachineInstrBuilder buildSpecConstantOp(MachineInstr &I, Register Dest,
254                                           Register Src, Register DestType,
255                                           uint32_t Opcode) const;
256   MachineInstrBuilder buildConstGenericPtr(MachineInstr &I, Register SrcPtr,
257                                            SPIRVType *SrcPtrTy) const;
258   Register buildPointerToResource(const SPIRVType *ResType, uint32_t Set,
259                                   uint32_t Binding, uint32_t ArraySize,
260                                   MachineIRBuilder MIRBuilder) const;
261 };
262 
263 } // end anonymous namespace
264 
265 #define GET_GLOBALISEL_IMPL
266 #include "SPIRVGenGlobalISel.inc"
267 #undef GET_GLOBALISEL_IMPL
268 
269 SPIRVInstructionSelector::SPIRVInstructionSelector(const SPIRVTargetMachine &TM,
270                                                    const SPIRVSubtarget &ST,
271                                                    const RegisterBankInfo &RBI)
272     : InstructionSelector(), STI(ST), TII(*ST.getInstrInfo()),
273       TRI(*ST.getRegisterInfo()), RBI(RBI), GR(*ST.getSPIRVGlobalRegistry()),
274 #define GET_GLOBALISEL_PREDICATES_INIT
275 #include "SPIRVGenGlobalISel.inc"
276 #undef GET_GLOBALISEL_PREDICATES_INIT
277 #define GET_GLOBALISEL_TEMPORARIES_INIT
278 #include "SPIRVGenGlobalISel.inc"
279 #undef GET_GLOBALISEL_TEMPORARIES_INIT
280 {
281 }
282 
283 void SPIRVInstructionSelector::setupMF(MachineFunction &MF, GISelKnownBits *KB,
284                                        CodeGenCoverage *CoverageInfo,
285                                        ProfileSummaryInfo *PSI,
286                                        BlockFrequencyInfo *BFI) {
287   MRI = &MF.getRegInfo();
288   GR.setCurrentFunc(MF);
289   InstructionSelector::setupMF(MF, KB, CoverageInfo, PSI, BFI);
290 }
291 
292 // Ensure that register classes correspond to pattern matching rules.
293 void SPIRVInstructionSelector::resetVRegsType(MachineFunction &MF) {
294   if (HasVRegsReset == &MF)
295     return;
296   HasVRegsReset = &MF;
297 
298   MachineRegisterInfo &MRI = MF.getRegInfo();
299   for (unsigned I = 0, E = MRI.getNumVirtRegs(); I != E; ++I) {
300     Register Reg = Register::index2VirtReg(I);
301     LLT RegType = MRI.getType(Reg);
302     if (RegType.isScalar())
303       MRI.setType(Reg, LLT::scalar(64));
304     else if (RegType.isPointer())
305       MRI.setType(Reg, LLT::pointer(0, 64));
306     else if (RegType.isVector())
307       MRI.setType(Reg, LLT::fixed_vector(2, LLT::scalar(64)));
308   }
309   for (const auto &MBB : MF) {
310     for (const auto &MI : MBB) {
311       if (MI.getOpcode() != SPIRV::ASSIGN_TYPE)
312         continue;
313       Register DstReg = MI.getOperand(0).getReg();
314       LLT DstType = MRI.getType(DstReg);
315       Register SrcReg = MI.getOperand(1).getReg();
316       LLT SrcType = MRI.getType(SrcReg);
317       if (DstType != SrcType)
318         MRI.setType(DstReg, MRI.getType(SrcReg));
319 
320       const TargetRegisterClass *DstRC = MRI.getRegClassOrNull(DstReg);
321       const TargetRegisterClass *SrcRC = MRI.getRegClassOrNull(SrcReg);
322       if (DstRC != SrcRC && SrcRC)
323         MRI.setRegClass(DstReg, SrcRC);
324     }
325   }
326 }
327 
328 static bool isImm(const MachineOperand &MO, MachineRegisterInfo *MRI);
329 
330 // Defined in SPIRVLegalizerInfo.cpp.
331 extern bool isTypeFoldingSupported(unsigned Opcode);
332 
333 bool SPIRVInstructionSelector::select(MachineInstr &I) {
334   resetVRegsType(*I.getParent()->getParent());
335 
336   assert(I.getParent() && "Instruction should be in a basic block!");
337   assert(I.getParent()->getParent() && "Instruction should be in a function!");
338 
339   Register Opcode = I.getOpcode();
340   // If it's not a GMIR instruction, we've selected it already.
341   if (!isPreISelGenericOpcode(Opcode)) {
342     if (Opcode == SPIRV::ASSIGN_TYPE) { // These pseudos aren't needed any more.
343       Register DstReg = I.getOperand(0).getReg();
344       Register SrcReg = I.getOperand(1).getReg();
345       auto *Def = MRI->getVRegDef(SrcReg);
346       if (isTypeFoldingSupported(Def->getOpcode())) {
347         bool Res = selectImpl(I, *CoverageInfo);
348         LLVM_DEBUG({
349           if (!Res && Def->getOpcode() != TargetOpcode::G_CONSTANT) {
350             dbgs() << "Unexpected pattern in ASSIGN_TYPE.\nInstruction: ";
351             I.print(dbgs());
352           }
353         });
354         assert(Res || Def->getOpcode() == TargetOpcode::G_CONSTANT);
355         if (Res)
356           return Res;
357       }
358       MRI->setRegClass(SrcReg, MRI->getRegClass(DstReg));
359       MRI->replaceRegWith(SrcReg, DstReg);
360       I.removeFromParent();
361       return true;
362     } else if (I.getNumDefs() == 1) {
363       // Make all vregs 64 bits (for SPIR-V IDs).
364       MRI->setType(I.getOperand(0).getReg(), LLT::scalar(64));
365     }
366     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
367   }
368 
369   if (I.getNumOperands() != I.getNumExplicitOperands()) {
370     LLVM_DEBUG(errs() << "Generic instr has unexpected implicit operands\n");
371     return false;
372   }
373 
374   // Common code for getting return reg+type, and removing selected instr
375   // from parent occurs here. Instr-specific selection happens in spvSelect().
376   bool HasDefs = I.getNumDefs() > 0;
377   Register ResVReg = HasDefs ? I.getOperand(0).getReg() : Register(0);
378   SPIRVType *ResType = HasDefs ? GR.getSPIRVTypeForVReg(ResVReg) : nullptr;
379   assert(!HasDefs || ResType || I.getOpcode() == TargetOpcode::G_GLOBAL_VALUE);
380   if (spvSelect(ResVReg, ResType, I)) {
381     if (HasDefs) // Make all vregs 64 bits (for SPIR-V IDs).
382       for (unsigned i = 0; i < I.getNumDefs(); ++i)
383         MRI->setType(I.getOperand(i).getReg(), LLT::scalar(64));
384     I.removeFromParent();
385     return true;
386   }
387   return false;
388 }
389 
390 static bool mayApplyGenericSelection(unsigned Opcode) {
391   switch (Opcode) {
392   case TargetOpcode::G_CONSTANT:
393     return false;
394   case TargetOpcode::G_SADDO:
395   case TargetOpcode::G_SSUBO:
396     return true;
397   }
398   return isTypeFoldingSupported(Opcode);
399 }
400 
401 bool SPIRVInstructionSelector::spvSelect(Register ResVReg,
402                                          const SPIRVType *ResType,
403                                          MachineInstr &I) const {
404   const unsigned Opcode = I.getOpcode();
405   if (mayApplyGenericSelection(Opcode))
406     return selectImpl(I, *CoverageInfo);
407   switch (Opcode) {
408   case TargetOpcode::G_CONSTANT:
409     return selectConst(ResVReg, ResType, I.getOperand(1).getCImm()->getValue(),
410                        I);
411   case TargetOpcode::G_GLOBAL_VALUE:
412     return selectGlobalValue(ResVReg, I);
413   case TargetOpcode::G_IMPLICIT_DEF:
414     return selectOpUndef(ResVReg, ResType, I);
415   case TargetOpcode::G_FREEZE:
416     return selectFreeze(ResVReg, ResType, I);
417 
418   case TargetOpcode::G_INTRINSIC:
419   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
420   case TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS:
421     return selectIntrinsic(ResVReg, ResType, I);
422   case TargetOpcode::G_BITREVERSE:
423     return selectBitreverse(ResVReg, ResType, I);
424 
425   case TargetOpcode::G_BUILD_VECTOR:
426     return selectBuildVector(ResVReg, ResType, I);
427   case TargetOpcode::G_SPLAT_VECTOR:
428     return selectSplatVector(ResVReg, ResType, I);
429 
430   case TargetOpcode::G_SHUFFLE_VECTOR: {
431     MachineBasicBlock &BB = *I.getParent();
432     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorShuffle))
433                    .addDef(ResVReg)
434                    .addUse(GR.getSPIRVTypeID(ResType))
435                    .addUse(I.getOperand(1).getReg())
436                    .addUse(I.getOperand(2).getReg());
437     for (auto V : I.getOperand(3).getShuffleMask())
438       MIB.addImm(V);
439     return MIB.constrainAllUses(TII, TRI, RBI);
440   }
441   case TargetOpcode::G_MEMMOVE:
442   case TargetOpcode::G_MEMCPY:
443   case TargetOpcode::G_MEMSET:
444     return selectMemOperation(ResVReg, I);
445 
446   case TargetOpcode::G_ICMP:
447     return selectICmp(ResVReg, ResType, I);
448   case TargetOpcode::G_FCMP:
449     return selectFCmp(ResVReg, ResType, I);
450 
451   case TargetOpcode::G_FRAME_INDEX:
452     return selectFrameIndex(ResVReg, ResType, I);
453 
454   case TargetOpcode::G_LOAD:
455     return selectLoad(ResVReg, ResType, I);
456   case TargetOpcode::G_STORE:
457     return selectStore(I);
458 
459   case TargetOpcode::G_BR:
460     return selectBranch(I);
461   case TargetOpcode::G_BRCOND:
462     return selectBranchCond(I);
463 
464   case TargetOpcode::G_PHI:
465     return selectPhi(ResVReg, ResType, I);
466 
467   case TargetOpcode::G_FPTOSI:
468     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertFToS);
469   case TargetOpcode::G_FPTOUI:
470     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertFToU);
471 
472   case TargetOpcode::G_SITOFP:
473     return selectIToF(ResVReg, ResType, I, true, SPIRV::OpConvertSToF);
474   case TargetOpcode::G_UITOFP:
475     return selectIToF(ResVReg, ResType, I, false, SPIRV::OpConvertUToF);
476 
477   case TargetOpcode::G_CTPOP:
478     return selectUnOp(ResVReg, ResType, I, SPIRV::OpBitCount);
479   case TargetOpcode::G_SMIN:
480     return selectExtInst(ResVReg, ResType, I, CL::s_min, GL::SMin);
481   case TargetOpcode::G_UMIN:
482     return selectExtInst(ResVReg, ResType, I, CL::u_min, GL::UMin);
483 
484   case TargetOpcode::G_SMAX:
485     return selectExtInst(ResVReg, ResType, I, CL::s_max, GL::SMax);
486   case TargetOpcode::G_UMAX:
487     return selectExtInst(ResVReg, ResType, I, CL::u_max, GL::UMax);
488 
489   case TargetOpcode::G_FMA:
490     return selectExtInst(ResVReg, ResType, I, CL::fma, GL::Fma);
491 
492   case TargetOpcode::G_FPOW:
493     return selectExtInst(ResVReg, ResType, I, CL::pow, GL::Pow);
494   case TargetOpcode::G_FPOWI:
495     return selectExtInst(ResVReg, ResType, I, CL::pown);
496 
497   case TargetOpcode::G_FEXP:
498     return selectExtInst(ResVReg, ResType, I, CL::exp, GL::Exp);
499   case TargetOpcode::G_FEXP2:
500     return selectExtInst(ResVReg, ResType, I, CL::exp2, GL::Exp2);
501 
502   case TargetOpcode::G_FLOG:
503     return selectExtInst(ResVReg, ResType, I, CL::log, GL::Log);
504   case TargetOpcode::G_FLOG2:
505     return selectExtInst(ResVReg, ResType, I, CL::log2, GL::Log2);
506   case TargetOpcode::G_FLOG10:
507     return selectLog10(ResVReg, ResType, I);
508 
509   case TargetOpcode::G_FABS:
510     return selectExtInst(ResVReg, ResType, I, CL::fabs, GL::FAbs);
511   case TargetOpcode::G_ABS:
512     return selectExtInst(ResVReg, ResType, I, CL::s_abs, GL::SAbs);
513 
514   case TargetOpcode::G_FMINNUM:
515   case TargetOpcode::G_FMINIMUM:
516     return selectExtInst(ResVReg, ResType, I, CL::fmin, GL::NMin);
517   case TargetOpcode::G_FMAXNUM:
518   case TargetOpcode::G_FMAXIMUM:
519     return selectExtInst(ResVReg, ResType, I, CL::fmax, GL::NMax);
520 
521   case TargetOpcode::G_FCOPYSIGN:
522     return selectExtInst(ResVReg, ResType, I, CL::copysign);
523 
524   case TargetOpcode::G_FCEIL:
525     return selectExtInst(ResVReg, ResType, I, CL::ceil, GL::Ceil);
526   case TargetOpcode::G_FFLOOR:
527     return selectExtInst(ResVReg, ResType, I, CL::floor, GL::Floor);
528 
529   case TargetOpcode::G_FCOS:
530     return selectExtInst(ResVReg, ResType, I, CL::cos, GL::Cos);
531   case TargetOpcode::G_FSIN:
532     return selectExtInst(ResVReg, ResType, I, CL::sin, GL::Sin);
533   case TargetOpcode::G_FTAN:
534     return selectExtInst(ResVReg, ResType, I, CL::tan, GL::Tan);
535   case TargetOpcode::G_FACOS:
536     return selectExtInst(ResVReg, ResType, I, CL::acos, GL::Acos);
537   case TargetOpcode::G_FASIN:
538     return selectExtInst(ResVReg, ResType, I, CL::asin, GL::Asin);
539   case TargetOpcode::G_FATAN:
540     return selectExtInst(ResVReg, ResType, I, CL::atan, GL::Atan);
541   case TargetOpcode::G_FATAN2:
542     return selectExtInst(ResVReg, ResType, I, CL::atan2, GL::Atan2);
543   case TargetOpcode::G_FCOSH:
544     return selectExtInst(ResVReg, ResType, I, CL::cosh, GL::Cosh);
545   case TargetOpcode::G_FSINH:
546     return selectExtInst(ResVReg, ResType, I, CL::sinh, GL::Sinh);
547   case TargetOpcode::G_FTANH:
548     return selectExtInst(ResVReg, ResType, I, CL::tanh, GL::Tanh);
549 
550   case TargetOpcode::G_FSQRT:
551     return selectExtInst(ResVReg, ResType, I, CL::sqrt, GL::Sqrt);
552 
553   case TargetOpcode::G_CTTZ:
554   case TargetOpcode::G_CTTZ_ZERO_UNDEF:
555     return selectExtInst(ResVReg, ResType, I, CL::ctz);
556   case TargetOpcode::G_CTLZ:
557   case TargetOpcode::G_CTLZ_ZERO_UNDEF:
558     return selectExtInst(ResVReg, ResType, I, CL::clz);
559 
560   case TargetOpcode::G_INTRINSIC_ROUND:
561     return selectExtInst(ResVReg, ResType, I, CL::round, GL::Round);
562   case TargetOpcode::G_INTRINSIC_ROUNDEVEN:
563     return selectExtInst(ResVReg, ResType, I, CL::rint, GL::RoundEven);
564   case TargetOpcode::G_INTRINSIC_TRUNC:
565     return selectExtInst(ResVReg, ResType, I, CL::trunc, GL::Trunc);
566   case TargetOpcode::G_FRINT:
567   case TargetOpcode::G_FNEARBYINT:
568     return selectExtInst(ResVReg, ResType, I, CL::rint, GL::RoundEven);
569 
570   case TargetOpcode::G_SMULH:
571     return selectExtInst(ResVReg, ResType, I, CL::s_mul_hi);
572   case TargetOpcode::G_UMULH:
573     return selectExtInst(ResVReg, ResType, I, CL::u_mul_hi);
574 
575   case TargetOpcode::G_SADDSAT:
576     return selectExtInst(ResVReg, ResType, I, CL::s_add_sat);
577   case TargetOpcode::G_UADDSAT:
578     return selectExtInst(ResVReg, ResType, I, CL::u_add_sat);
579   case TargetOpcode::G_SSUBSAT:
580     return selectExtInst(ResVReg, ResType, I, CL::s_sub_sat);
581   case TargetOpcode::G_USUBSAT:
582     return selectExtInst(ResVReg, ResType, I, CL::u_sub_sat);
583 
584   case TargetOpcode::G_UADDO:
585     return selectOverflowArith(ResVReg, ResType, I,
586                                ResType->getOpcode() == SPIRV::OpTypeVector
587                                    ? SPIRV::OpIAddCarryV
588                                    : SPIRV::OpIAddCarryS);
589   case TargetOpcode::G_USUBO:
590     return selectOverflowArith(ResVReg, ResType, I,
591                                ResType->getOpcode() == SPIRV::OpTypeVector
592                                    ? SPIRV::OpISubBorrowV
593                                    : SPIRV::OpISubBorrowS);
594   case TargetOpcode::G_UMULO:
595     return selectOverflowArith(ResVReg, ResType, I, SPIRV::OpUMulExtended);
596   case TargetOpcode::G_SMULO:
597     return selectOverflowArith(ResVReg, ResType, I, SPIRV::OpSMulExtended);
598 
599   case TargetOpcode::G_SEXT:
600     return selectExt(ResVReg, ResType, I, true);
601   case TargetOpcode::G_ANYEXT:
602   case TargetOpcode::G_ZEXT:
603     return selectExt(ResVReg, ResType, I, false);
604   case TargetOpcode::G_TRUNC:
605     return selectTrunc(ResVReg, ResType, I);
606   case TargetOpcode::G_FPTRUNC:
607   case TargetOpcode::G_FPEXT:
608     return selectUnOp(ResVReg, ResType, I, SPIRV::OpFConvert);
609 
610   case TargetOpcode::G_PTRTOINT:
611     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertPtrToU);
612   case TargetOpcode::G_INTTOPTR:
613     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertUToPtr);
614   case TargetOpcode::G_BITCAST:
615     return selectBitcast(ResVReg, ResType, I);
616   case TargetOpcode::G_ADDRSPACE_CAST:
617     return selectAddrSpaceCast(ResVReg, ResType, I);
618   case TargetOpcode::G_PTR_ADD: {
619     // Currently, we get G_PTR_ADD only applied to global variables.
620     assert(I.getOperand(1).isReg() && I.getOperand(2).isReg());
621     Register GV = I.getOperand(1).getReg();
622     MachineRegisterInfo::def_instr_iterator II = MRI->def_instr_begin(GV);
623     (void)II;
624     assert(((*II).getOpcode() == TargetOpcode::G_GLOBAL_VALUE ||
625             (*II).getOpcode() == TargetOpcode::COPY ||
626             (*II).getOpcode() == SPIRV::OpVariable) &&
627            isImm(I.getOperand(2), MRI));
628     // It may be the initialization of a global variable.
629     bool IsGVInit = false;
630     for (MachineRegisterInfo::use_instr_iterator
631              UseIt = MRI->use_instr_begin(I.getOperand(0).getReg()),
632              UseEnd = MRI->use_instr_end();
633          UseIt != UseEnd; UseIt = std::next(UseIt)) {
634       if ((*UseIt).getOpcode() == TargetOpcode::G_GLOBAL_VALUE ||
635           (*UseIt).getOpcode() == SPIRV::OpVariable) {
636         IsGVInit = true;
637         break;
638       }
639     }
640     MachineBasicBlock &BB = *I.getParent();
641     if (!IsGVInit) {
642       SPIRVType *GVType = GR.getSPIRVTypeForVReg(GV);
643       SPIRVType *GVPointeeType = GR.getPointeeType(GVType);
644       SPIRVType *ResPointeeType = GR.getPointeeType(ResType);
645       if (GVPointeeType && ResPointeeType && GVPointeeType != ResPointeeType) {
646         // Build a new virtual register that is associated with the required
647         // data type.
648         Register NewVReg = MRI->createGenericVirtualRegister(MRI->getType(GV));
649         MRI->setRegClass(NewVReg, MRI->getRegClass(GV));
650         //  Having a correctly typed base we are ready to build the actually
651         //  required GEP. It may not be a constant though, because all Operands
652         //  of OpSpecConstantOp is to originate from other const instructions,
653         //  and only the AccessChain named opcodes accept a global OpVariable
654         //  instruction. We can't use an AccessChain opcode because of the type
655         //  mismatch between result and base types.
656         if (!GR.isBitcastCompatible(ResType, GVType))
657           report_fatal_error(
658               "incompatible result and operand types in a bitcast");
659         Register ResTypeReg = GR.getSPIRVTypeID(ResType);
660         MachineInstrBuilder MIB =
661             BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpBitcast))
662                 .addDef(NewVReg)
663                 .addUse(ResTypeReg)
664                 .addUse(GV);
665         return MIB.constrainAllUses(TII, TRI, RBI) &&
666                BuildMI(BB, I, I.getDebugLoc(),
667                        TII.get(STI.isVulkanEnv()
668                                    ? SPIRV::OpInBoundsAccessChain
669                                    : SPIRV::OpInBoundsPtrAccessChain))
670                    .addDef(ResVReg)
671                    .addUse(ResTypeReg)
672                    .addUse(NewVReg)
673                    .addUse(I.getOperand(2).getReg())
674                    .constrainAllUses(TII, TRI, RBI);
675       } else {
676         return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
677             .addDef(ResVReg)
678             .addUse(GR.getSPIRVTypeID(ResType))
679             .addImm(
680                 static_cast<uint32_t>(SPIRV::Opcode::InBoundsPtrAccessChain))
681             .addUse(GV)
682             .addUse(I.getOperand(2).getReg())
683             .constrainAllUses(TII, TRI, RBI);
684       }
685     }
686     // It's possible to translate G_PTR_ADD to OpSpecConstantOp: either to
687     // initialize a global variable with a constant expression (e.g., the test
688     // case opencl/basic/progvar_prog_scope_init.ll), or for another use case
689     Register Idx = buildZerosVal(GR.getOrCreateSPIRVIntegerType(32, I, TII), I);
690     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
691                    .addDef(ResVReg)
692                    .addUse(GR.getSPIRVTypeID(ResType))
693                    .addImm(static_cast<uint32_t>(
694                        SPIRV::Opcode::InBoundsPtrAccessChain))
695                    .addUse(GV)
696                    .addUse(Idx)
697                    .addUse(I.getOperand(2).getReg());
698     return MIB.constrainAllUses(TII, TRI, RBI);
699   }
700 
701   case TargetOpcode::G_ATOMICRMW_OR:
702     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicOr);
703   case TargetOpcode::G_ATOMICRMW_ADD:
704     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicIAdd);
705   case TargetOpcode::G_ATOMICRMW_AND:
706     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicAnd);
707   case TargetOpcode::G_ATOMICRMW_MAX:
708     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicSMax);
709   case TargetOpcode::G_ATOMICRMW_MIN:
710     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicSMin);
711   case TargetOpcode::G_ATOMICRMW_SUB:
712     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicISub);
713   case TargetOpcode::G_ATOMICRMW_XOR:
714     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicXor);
715   case TargetOpcode::G_ATOMICRMW_UMAX:
716     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicUMax);
717   case TargetOpcode::G_ATOMICRMW_UMIN:
718     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicUMin);
719   case TargetOpcode::G_ATOMICRMW_XCHG:
720     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicExchange);
721   case TargetOpcode::G_ATOMIC_CMPXCHG:
722     return selectAtomicCmpXchg(ResVReg, ResType, I);
723 
724   case TargetOpcode::G_ATOMICRMW_FADD:
725     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFAddEXT);
726   case TargetOpcode::G_ATOMICRMW_FSUB:
727     // Translate G_ATOMICRMW_FSUB to OpAtomicFAddEXT with negative value operand
728     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFAddEXT,
729                            SPIRV::OpFNegate);
730   case TargetOpcode::G_ATOMICRMW_FMIN:
731     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFMinEXT);
732   case TargetOpcode::G_ATOMICRMW_FMAX:
733     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFMaxEXT);
734 
735   case TargetOpcode::G_FENCE:
736     return selectFence(I);
737 
738   case TargetOpcode::G_STACKSAVE:
739     return selectStackSave(ResVReg, ResType, I);
740   case TargetOpcode::G_STACKRESTORE:
741     return selectStackRestore(I);
742 
743   case TargetOpcode::G_UNMERGE_VALUES:
744     return selectUnmergeValues(I);
745 
746   // Discard gen opcodes for intrinsics which we do not expect to actually
747   // represent code after lowering or intrinsics which are not implemented but
748   // should not crash when found in a customer's LLVM IR input.
749   case TargetOpcode::G_TRAP:
750   case TargetOpcode::G_DEBUGTRAP:
751   case TargetOpcode::G_UBSANTRAP:
752   case TargetOpcode::DBG_LABEL:
753     return true;
754 
755   default:
756     return false;
757   }
758 }
759 
760 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
761                                              const SPIRVType *ResType,
762                                              MachineInstr &I,
763                                              CL::OpenCLExtInst CLInst) const {
764   return selectExtInst(ResVReg, ResType, I,
765                        {{SPIRV::InstructionSet::OpenCL_std, CLInst}});
766 }
767 
768 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
769                                              const SPIRVType *ResType,
770                                              MachineInstr &I,
771                                              CL::OpenCLExtInst CLInst,
772                                              GL::GLSLExtInst GLInst) const {
773   ExtInstList ExtInsts = {{SPIRV::InstructionSet::OpenCL_std, CLInst},
774                           {SPIRV::InstructionSet::GLSL_std_450, GLInst}};
775   return selectExtInst(ResVReg, ResType, I, ExtInsts);
776 }
777 
778 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
779                                              const SPIRVType *ResType,
780                                              MachineInstr &I,
781                                              const ExtInstList &Insts) const {
782 
783   for (const auto &Ex : Insts) {
784     SPIRV::InstructionSet::InstructionSet Set = Ex.first;
785     uint32_t Opcode = Ex.second;
786     if (STI.canUseExtInstSet(Set)) {
787       MachineBasicBlock &BB = *I.getParent();
788       auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
789                      .addDef(ResVReg)
790                      .addUse(GR.getSPIRVTypeID(ResType))
791                      .addImm(static_cast<uint32_t>(Set))
792                      .addImm(Opcode);
793       const unsigned NumOps = I.getNumOperands();
794       unsigned Index = 1;
795       if (Index < NumOps &&
796           I.getOperand(Index).getType() ==
797               MachineOperand::MachineOperandType::MO_IntrinsicID)
798         Index = 2;
799       for (; Index < NumOps; ++Index)
800         MIB.add(I.getOperand(Index));
801       return MIB.constrainAllUses(TII, TRI, RBI);
802     }
803   }
804   return false;
805 }
806 
807 bool SPIRVInstructionSelector::selectUnOpWithSrc(Register ResVReg,
808                                                  const SPIRVType *ResType,
809                                                  MachineInstr &I,
810                                                  Register SrcReg,
811                                                  unsigned Opcode) const {
812   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
813       .addDef(ResVReg)
814       .addUse(GR.getSPIRVTypeID(ResType))
815       .addUse(SrcReg)
816       .constrainAllUses(TII, TRI, RBI);
817 }
818 
819 bool SPIRVInstructionSelector::selectUnOp(Register ResVReg,
820                                           const SPIRVType *ResType,
821                                           MachineInstr &I,
822                                           unsigned Opcode) const {
823   if (STI.isOpenCLEnv() && I.getOperand(1).isReg()) {
824     Register SrcReg = I.getOperand(1).getReg();
825     bool IsGV = false;
826     for (MachineRegisterInfo::def_instr_iterator DefIt =
827              MRI->def_instr_begin(SrcReg);
828          DefIt != MRI->def_instr_end(); DefIt = std::next(DefIt)) {
829       if ((*DefIt).getOpcode() == TargetOpcode::G_GLOBAL_VALUE) {
830         IsGV = true;
831         break;
832       }
833     }
834     if (IsGV) {
835       uint32_t SpecOpcode = 0;
836       switch (Opcode) {
837       case SPIRV::OpConvertPtrToU:
838         SpecOpcode = static_cast<uint32_t>(SPIRV::Opcode::ConvertPtrToU);
839         break;
840       case SPIRV::OpConvertUToPtr:
841         SpecOpcode = static_cast<uint32_t>(SPIRV::Opcode::ConvertUToPtr);
842         break;
843       }
844       if (SpecOpcode)
845         return BuildMI(*I.getParent(), I, I.getDebugLoc(),
846                        TII.get(SPIRV::OpSpecConstantOp))
847             .addDef(ResVReg)
848             .addUse(GR.getSPIRVTypeID(ResType))
849             .addImm(SpecOpcode)
850             .addUse(SrcReg)
851             .constrainAllUses(TII, TRI, RBI);
852     }
853   }
854   return selectUnOpWithSrc(ResVReg, ResType, I, I.getOperand(1).getReg(),
855                            Opcode);
856 }
857 
858 bool SPIRVInstructionSelector::selectBitcast(Register ResVReg,
859                                              const SPIRVType *ResType,
860                                              MachineInstr &I) const {
861   Register OpReg = I.getOperand(1).getReg();
862   SPIRVType *OpType = OpReg.isValid() ? GR.getSPIRVTypeForVReg(OpReg) : nullptr;
863   if (!GR.isBitcastCompatible(ResType, OpType))
864     report_fatal_error("incompatible result and operand types in a bitcast");
865   return selectUnOp(ResVReg, ResType, I, SPIRV::OpBitcast);
866 }
867 
868 static void addMemoryOperands(MachineMemOperand *MemOp,
869                               MachineInstrBuilder &MIB) {
870   uint32_t SpvMemOp = static_cast<uint32_t>(SPIRV::MemoryOperand::None);
871   if (MemOp->isVolatile())
872     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Volatile);
873   if (MemOp->isNonTemporal())
874     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Nontemporal);
875   if (MemOp->getAlign().value())
876     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Aligned);
877 
878   if (SpvMemOp != static_cast<uint32_t>(SPIRV::MemoryOperand::None)) {
879     MIB.addImm(SpvMemOp);
880     if (SpvMemOp & static_cast<uint32_t>(SPIRV::MemoryOperand::Aligned))
881       MIB.addImm(MemOp->getAlign().value());
882   }
883 }
884 
885 static void addMemoryOperands(uint64_t Flags, MachineInstrBuilder &MIB) {
886   uint32_t SpvMemOp = static_cast<uint32_t>(SPIRV::MemoryOperand::None);
887   if (Flags & MachineMemOperand::Flags::MOVolatile)
888     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Volatile);
889   if (Flags & MachineMemOperand::Flags::MONonTemporal)
890     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Nontemporal);
891 
892   if (SpvMemOp != static_cast<uint32_t>(SPIRV::MemoryOperand::None))
893     MIB.addImm(SpvMemOp);
894 }
895 
896 bool SPIRVInstructionSelector::selectLoad(Register ResVReg,
897                                           const SPIRVType *ResType,
898                                           MachineInstr &I) const {
899   unsigned OpOffset = isa<GIntrinsic>(I) ? 1 : 0;
900   Register Ptr = I.getOperand(1 + OpOffset).getReg();
901   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
902                  .addDef(ResVReg)
903                  .addUse(GR.getSPIRVTypeID(ResType))
904                  .addUse(Ptr);
905   if (!I.getNumMemOperands()) {
906     assert(I.getOpcode() == TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS ||
907            I.getOpcode() ==
908                TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS);
909     addMemoryOperands(I.getOperand(2 + OpOffset).getImm(), MIB);
910   } else {
911     addMemoryOperands(*I.memoperands_begin(), MIB);
912   }
913   return MIB.constrainAllUses(TII, TRI, RBI);
914 }
915 
916 bool SPIRVInstructionSelector::selectStore(MachineInstr &I) const {
917   unsigned OpOffset = isa<GIntrinsic>(I) ? 1 : 0;
918   Register StoreVal = I.getOperand(0 + OpOffset).getReg();
919   Register Ptr = I.getOperand(1 + OpOffset).getReg();
920   MachineBasicBlock &BB = *I.getParent();
921   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpStore))
922                  .addUse(Ptr)
923                  .addUse(StoreVal);
924   if (!I.getNumMemOperands()) {
925     assert(I.getOpcode() == TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS ||
926            I.getOpcode() ==
927                TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS);
928     addMemoryOperands(I.getOperand(2 + OpOffset).getImm(), MIB);
929   } else {
930     addMemoryOperands(*I.memoperands_begin(), MIB);
931   }
932   return MIB.constrainAllUses(TII, TRI, RBI);
933 }
934 
935 bool SPIRVInstructionSelector::selectStackSave(Register ResVReg,
936                                                const SPIRVType *ResType,
937                                                MachineInstr &I) const {
938   if (!STI.canUseExtension(SPIRV::Extension::SPV_INTEL_variable_length_array))
939     report_fatal_error(
940         "llvm.stacksave intrinsic: this instruction requires the following "
941         "SPIR-V extension: SPV_INTEL_variable_length_array",
942         false);
943   MachineBasicBlock &BB = *I.getParent();
944   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSaveMemoryINTEL))
945       .addDef(ResVReg)
946       .addUse(GR.getSPIRVTypeID(ResType))
947       .constrainAllUses(TII, TRI, RBI);
948 }
949 
950 bool SPIRVInstructionSelector::selectStackRestore(MachineInstr &I) const {
951   if (!STI.canUseExtension(SPIRV::Extension::SPV_INTEL_variable_length_array))
952     report_fatal_error(
953         "llvm.stackrestore intrinsic: this instruction requires the following "
954         "SPIR-V extension: SPV_INTEL_variable_length_array",
955         false);
956   if (!I.getOperand(0).isReg())
957     return false;
958   MachineBasicBlock &BB = *I.getParent();
959   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpRestoreMemoryINTEL))
960       .addUse(I.getOperand(0).getReg())
961       .constrainAllUses(TII, TRI, RBI);
962 }
963 
964 bool SPIRVInstructionSelector::selectMemOperation(Register ResVReg,
965                                                   MachineInstr &I) const {
966   MachineBasicBlock &BB = *I.getParent();
967   Register SrcReg = I.getOperand(1).getReg();
968   if (I.getOpcode() == TargetOpcode::G_MEMSET) {
969     assert(I.getOperand(1).isReg() && I.getOperand(2).isReg());
970     unsigned Val = getIConstVal(I.getOperand(1).getReg(), MRI);
971     unsigned Num = getIConstVal(I.getOperand(2).getReg(), MRI);
972     SPIRVType *ValTy = GR.getOrCreateSPIRVIntegerType(8, I, TII);
973     SPIRVType *ArrTy = GR.getOrCreateSPIRVArrayType(ValTy, Num, I, TII);
974     Register Const = GR.getOrCreateConstIntArray(Val, Num, I, ArrTy, TII);
975     SPIRVType *VarTy = GR.getOrCreateSPIRVPointerType(
976         ArrTy, I, TII, SPIRV::StorageClass::UniformConstant);
977     // TODO: check if we have such GV, add init, use buildGlobalVariable.
978     Function &CurFunction = GR.CurMF->getFunction();
979     Type *LLVMArrTy =
980         ArrayType::get(IntegerType::get(CurFunction.getContext(), 8), Num);
981     // Module takes ownership of the global var.
982     GlobalVariable *GV = new GlobalVariable(*CurFunction.getParent(), LLVMArrTy,
983                                             true, GlobalValue::InternalLinkage,
984                                             Constant::getNullValue(LLVMArrTy));
985     Register VarReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
986     GR.add(GV, GR.CurMF, VarReg);
987 
988     buildOpDecorate(VarReg, I, TII, SPIRV::Decoration::Constant, {});
989     BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpVariable))
990         .addDef(VarReg)
991         .addUse(GR.getSPIRVTypeID(VarTy))
992         .addImm(SPIRV::StorageClass::UniformConstant)
993         .addUse(Const)
994         .constrainAllUses(TII, TRI, RBI);
995     SPIRVType *SourceTy = GR.getOrCreateSPIRVPointerType(
996         ValTy, I, TII, SPIRV::StorageClass::UniformConstant);
997     SrcReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
998     selectUnOpWithSrc(SrcReg, SourceTy, I, VarReg, SPIRV::OpBitcast);
999   }
1000   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCopyMemorySized))
1001                  .addUse(I.getOperand(0).getReg())
1002                  .addUse(SrcReg)
1003                  .addUse(I.getOperand(2).getReg());
1004   if (I.getNumMemOperands())
1005     addMemoryOperands(*I.memoperands_begin(), MIB);
1006   bool Result = MIB.constrainAllUses(TII, TRI, RBI);
1007   if (ResVReg.isValid() && ResVReg != MIB->getOperand(0).getReg())
1008     BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY), ResVReg)
1009         .addUse(MIB->getOperand(0).getReg());
1010   return Result;
1011 }
1012 
1013 bool SPIRVInstructionSelector::selectAtomicRMW(Register ResVReg,
1014                                                const SPIRVType *ResType,
1015                                                MachineInstr &I,
1016                                                unsigned NewOpcode,
1017                                                unsigned NegateOpcode) const {
1018   assert(I.hasOneMemOperand());
1019   const MachineMemOperand *MemOp = *I.memoperands_begin();
1020   uint32_t Scope = static_cast<uint32_t>(getMemScope(
1021       GR.CurMF->getFunction().getContext(), MemOp->getSyncScopeID()));
1022   Register ScopeReg = buildI32Constant(Scope, I);
1023 
1024   Register Ptr = I.getOperand(1).getReg();
1025   // TODO: Changed as it's implemented in the translator. See test/atomicrmw.ll
1026   // auto ScSem =
1027   // getMemSemanticsForStorageClass(GR.getPointerStorageClass(Ptr));
1028   AtomicOrdering AO = MemOp->getSuccessOrdering();
1029   uint32_t MemSem = static_cast<uint32_t>(getMemSemantics(AO));
1030   Register MemSemReg = buildI32Constant(MemSem /*| ScSem*/, I);
1031 
1032   bool Result = false;
1033   Register ValueReg = I.getOperand(2).getReg();
1034   if (NegateOpcode != 0) {
1035     // Translation with negative value operand is requested
1036     Register TmpReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1037     Result |= selectUnOpWithSrc(TmpReg, ResType, I, ValueReg, NegateOpcode);
1038     ValueReg = TmpReg;
1039   }
1040 
1041   Result |= BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(NewOpcode))
1042                 .addDef(ResVReg)
1043                 .addUse(GR.getSPIRVTypeID(ResType))
1044                 .addUse(Ptr)
1045                 .addUse(ScopeReg)
1046                 .addUse(MemSemReg)
1047                 .addUse(ValueReg)
1048                 .constrainAllUses(TII, TRI, RBI);
1049   return Result;
1050 }
1051 
1052 bool SPIRVInstructionSelector::selectUnmergeValues(MachineInstr &I) const {
1053   unsigned ArgI = I.getNumOperands() - 1;
1054   Register SrcReg =
1055       I.getOperand(ArgI).isReg() ? I.getOperand(ArgI).getReg() : Register(0);
1056   SPIRVType *DefType =
1057       SrcReg.isValid() ? GR.getSPIRVTypeForVReg(SrcReg) : nullptr;
1058   if (!DefType || DefType->getOpcode() != SPIRV::OpTypeVector)
1059     report_fatal_error(
1060         "cannot select G_UNMERGE_VALUES with a non-vector argument");
1061 
1062   SPIRVType *ScalarType =
1063       GR.getSPIRVTypeForVReg(DefType->getOperand(1).getReg());
1064   MachineBasicBlock &BB = *I.getParent();
1065   bool Res = false;
1066   for (unsigned i = 0; i < I.getNumDefs(); ++i) {
1067     Register ResVReg = I.getOperand(i).getReg();
1068     SPIRVType *ResType = GR.getSPIRVTypeForVReg(ResVReg);
1069     if (!ResType) {
1070       // There was no "assign type" actions, let's fix this now
1071       ResType = ScalarType;
1072       MRI->setRegClass(ResVReg, GR.getRegClass(ResType));
1073       MRI->setType(ResVReg, LLT::scalar(GR.getScalarOrVectorBitWidth(ResType)));
1074       GR.assignSPIRVTypeToVReg(ResType, ResVReg, *GR.CurMF);
1075     }
1076     auto MIB =
1077         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1078             .addDef(ResVReg)
1079             .addUse(GR.getSPIRVTypeID(ResType))
1080             .addUse(SrcReg)
1081             .addImm(static_cast<int64_t>(i));
1082     Res |= MIB.constrainAllUses(TII, TRI, RBI);
1083   }
1084   return Res;
1085 }
1086 
1087 bool SPIRVInstructionSelector::selectFence(MachineInstr &I) const {
1088   AtomicOrdering AO = AtomicOrdering(I.getOperand(0).getImm());
1089   uint32_t MemSem = static_cast<uint32_t>(getMemSemantics(AO));
1090   Register MemSemReg = buildI32Constant(MemSem, I);
1091   SyncScope::ID Ord = SyncScope::ID(I.getOperand(1).getImm());
1092   uint32_t Scope = static_cast<uint32_t>(
1093       getMemScope(GR.CurMF->getFunction().getContext(), Ord));
1094   Register ScopeReg = buildI32Constant(Scope, I);
1095   MachineBasicBlock &BB = *I.getParent();
1096   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpMemoryBarrier))
1097       .addUse(ScopeReg)
1098       .addUse(MemSemReg)
1099       .constrainAllUses(TII, TRI, RBI);
1100 }
1101 
1102 bool SPIRVInstructionSelector::selectOverflowArith(Register ResVReg,
1103                                                    const SPIRVType *ResType,
1104                                                    MachineInstr &I,
1105                                                    unsigned Opcode) const {
1106   Type *ResTy = nullptr;
1107   StringRef ResName;
1108   if (!GR.findValueAttrs(&I, ResTy, ResName))
1109     report_fatal_error(
1110         "Not enough info to select the arithmetic with overflow instruction");
1111   if (!ResTy || !ResTy->isStructTy())
1112     report_fatal_error("Expect struct type result for the arithmetic "
1113                        "with overflow instruction");
1114   // "Result Type must be from OpTypeStruct. The struct must have two members,
1115   // and the two members must be the same type."
1116   Type *ResElemTy = cast<StructType>(ResTy)->getElementType(0);
1117   ResTy = StructType::create(SmallVector<Type *, 2>{ResElemTy, ResElemTy});
1118   // Build SPIR-V types and constant(s) if needed.
1119   MachineIRBuilder MIRBuilder(I);
1120   SPIRVType *StructType = GR.getOrCreateSPIRVType(
1121       ResTy, MIRBuilder, SPIRV::AccessQualifier::ReadWrite, false);
1122   assert(I.getNumDefs() > 1 && "Not enought operands");
1123   SPIRVType *BoolType = GR.getOrCreateSPIRVBoolType(I, TII);
1124   unsigned N = GR.getScalarOrVectorComponentCount(ResType);
1125   if (N > 1)
1126     BoolType = GR.getOrCreateSPIRVVectorType(BoolType, N, I, TII);
1127   Register BoolTypeReg = GR.getSPIRVTypeID(BoolType);
1128   Register ZeroReg = buildZerosVal(ResType, I);
1129   // A new virtual register to store the result struct.
1130   Register StructVReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1131   MRI->setRegClass(StructVReg, &SPIRV::IDRegClass);
1132   // Build the result name if needed.
1133   if (ResName.size() > 0)
1134     buildOpName(StructVReg, ResName, MIRBuilder);
1135   // Build the arithmetic with overflow instruction.
1136   MachineBasicBlock &BB = *I.getParent();
1137   auto MIB =
1138       BuildMI(BB, MIRBuilder.getInsertPt(), I.getDebugLoc(), TII.get(Opcode))
1139           .addDef(StructVReg)
1140           .addUse(GR.getSPIRVTypeID(StructType));
1141   for (unsigned i = I.getNumDefs(); i < I.getNumOperands(); ++i)
1142     MIB.addUse(I.getOperand(i).getReg());
1143   bool Status = MIB.constrainAllUses(TII, TRI, RBI);
1144   // Build instructions to extract fields of the instruction's result.
1145   // A new virtual register to store the higher part of the result struct.
1146   Register HigherVReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1147   MRI->setRegClass(HigherVReg, &SPIRV::iIDRegClass);
1148   for (unsigned i = 0; i < I.getNumDefs(); ++i) {
1149     auto MIB =
1150         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1151             .addDef(i == 1 ? HigherVReg : I.getOperand(i).getReg())
1152             .addUse(GR.getSPIRVTypeID(ResType))
1153             .addUse(StructVReg)
1154             .addImm(i);
1155     Status &= MIB.constrainAllUses(TII, TRI, RBI);
1156   }
1157   // Build boolean value from the higher part.
1158   Status &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpINotEqual))
1159                 .addDef(I.getOperand(1).getReg())
1160                 .addUse(BoolTypeReg)
1161                 .addUse(HigherVReg)
1162                 .addUse(ZeroReg)
1163                 .constrainAllUses(TII, TRI, RBI);
1164   return Status;
1165 }
1166 
1167 bool SPIRVInstructionSelector::selectAtomicCmpXchg(Register ResVReg,
1168                                                    const SPIRVType *ResType,
1169                                                    MachineInstr &I) const {
1170   Register ScopeReg;
1171   Register MemSemEqReg;
1172   Register MemSemNeqReg;
1173   Register Ptr = I.getOperand(2).getReg();
1174   if (!isa<GIntrinsic>(I)) {
1175     assert(I.hasOneMemOperand());
1176     const MachineMemOperand *MemOp = *I.memoperands_begin();
1177     unsigned Scope = static_cast<uint32_t>(getMemScope(
1178         GR.CurMF->getFunction().getContext(), MemOp->getSyncScopeID()));
1179     ScopeReg = buildI32Constant(Scope, I);
1180 
1181     unsigned ScSem = static_cast<uint32_t>(
1182         getMemSemanticsForStorageClass(GR.getPointerStorageClass(Ptr)));
1183     AtomicOrdering AO = MemOp->getSuccessOrdering();
1184     unsigned MemSemEq = static_cast<uint32_t>(getMemSemantics(AO)) | ScSem;
1185     MemSemEqReg = buildI32Constant(MemSemEq, I);
1186     AtomicOrdering FO = MemOp->getFailureOrdering();
1187     unsigned MemSemNeq = static_cast<uint32_t>(getMemSemantics(FO)) | ScSem;
1188     MemSemNeqReg =
1189         MemSemEq == MemSemNeq ? MemSemEqReg : buildI32Constant(MemSemNeq, I);
1190   } else {
1191     ScopeReg = I.getOperand(5).getReg();
1192     MemSemEqReg = I.getOperand(6).getReg();
1193     MemSemNeqReg = I.getOperand(7).getReg();
1194   }
1195 
1196   Register Cmp = I.getOperand(3).getReg();
1197   Register Val = I.getOperand(4).getReg();
1198   SPIRVType *SpvValTy = GR.getSPIRVTypeForVReg(Val);
1199   Register ACmpRes = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1200   const DebugLoc &DL = I.getDebugLoc();
1201   bool Result =
1202       BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpAtomicCompareExchange))
1203           .addDef(ACmpRes)
1204           .addUse(GR.getSPIRVTypeID(SpvValTy))
1205           .addUse(Ptr)
1206           .addUse(ScopeReg)
1207           .addUse(MemSemEqReg)
1208           .addUse(MemSemNeqReg)
1209           .addUse(Val)
1210           .addUse(Cmp)
1211           .constrainAllUses(TII, TRI, RBI);
1212   Register CmpSuccReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1213   SPIRVType *BoolTy = GR.getOrCreateSPIRVBoolType(I, TII);
1214   Result |= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpIEqual))
1215                 .addDef(CmpSuccReg)
1216                 .addUse(GR.getSPIRVTypeID(BoolTy))
1217                 .addUse(ACmpRes)
1218                 .addUse(Cmp)
1219                 .constrainAllUses(TII, TRI, RBI);
1220   Register TmpReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1221   Result |= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpCompositeInsert))
1222                 .addDef(TmpReg)
1223                 .addUse(GR.getSPIRVTypeID(ResType))
1224                 .addUse(ACmpRes)
1225                 .addUse(GR.getOrCreateUndef(I, ResType, TII))
1226                 .addImm(0)
1227                 .constrainAllUses(TII, TRI, RBI);
1228   Result |= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpCompositeInsert))
1229                 .addDef(ResVReg)
1230                 .addUse(GR.getSPIRVTypeID(ResType))
1231                 .addUse(CmpSuccReg)
1232                 .addUse(TmpReg)
1233                 .addImm(1)
1234                 .constrainAllUses(TII, TRI, RBI);
1235   return Result;
1236 }
1237 
1238 static bool isGenericCastablePtr(SPIRV::StorageClass::StorageClass SC) {
1239   switch (SC) {
1240   case SPIRV::StorageClass::Workgroup:
1241   case SPIRV::StorageClass::CrossWorkgroup:
1242   case SPIRV::StorageClass::Function:
1243     return true;
1244   default:
1245     return false;
1246   }
1247 }
1248 
1249 static bool isUSMStorageClass(SPIRV::StorageClass::StorageClass SC) {
1250   switch (SC) {
1251   case SPIRV::StorageClass::DeviceOnlyINTEL:
1252   case SPIRV::StorageClass::HostOnlyINTEL:
1253     return true;
1254   default:
1255     return false;
1256   }
1257 }
1258 
1259 // Returns true ResVReg is referred only from global vars and OpName's.
1260 static bool isASCastInGVar(MachineRegisterInfo *MRI, Register ResVReg) {
1261   bool IsGRef = false;
1262   bool IsAllowedRefs =
1263       std::all_of(MRI->use_instr_begin(ResVReg), MRI->use_instr_end(),
1264                   [&IsGRef](auto const &It) {
1265                     unsigned Opcode = It.getOpcode();
1266                     if (Opcode == SPIRV::OpConstantComposite ||
1267                         Opcode == SPIRV::OpVariable ||
1268                         isSpvIntrinsic(It, Intrinsic::spv_init_global))
1269                       return IsGRef = true;
1270                     return Opcode == SPIRV::OpName;
1271                   });
1272   return IsAllowedRefs && IsGRef;
1273 }
1274 
1275 Register SPIRVInstructionSelector::getUcharPtrTypeReg(
1276     MachineInstr &I, SPIRV::StorageClass::StorageClass SC) const {
1277   return GR.getSPIRVTypeID(GR.getOrCreateSPIRVPointerType(
1278       GR.getOrCreateSPIRVIntegerType(8, I, TII), I, TII, SC));
1279 }
1280 
1281 MachineInstrBuilder
1282 SPIRVInstructionSelector::buildSpecConstantOp(MachineInstr &I, Register Dest,
1283                                               Register Src, Register DestType,
1284                                               uint32_t Opcode) const {
1285   return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1286                  TII.get(SPIRV::OpSpecConstantOp))
1287       .addDef(Dest)
1288       .addUse(DestType)
1289       .addImm(Opcode)
1290       .addUse(Src);
1291 }
1292 
1293 MachineInstrBuilder
1294 SPIRVInstructionSelector::buildConstGenericPtr(MachineInstr &I, Register SrcPtr,
1295                                                SPIRVType *SrcPtrTy) const {
1296   SPIRVType *GenericPtrTy = GR.getOrCreateSPIRVPointerType(
1297       GR.getPointeeType(SrcPtrTy), I, TII, SPIRV::StorageClass::Generic);
1298   Register Tmp = MRI->createVirtualRegister(&SPIRV::pIDRegClass);
1299   MRI->setType(Tmp, LLT::pointer(storageClassToAddressSpace(
1300                                      SPIRV::StorageClass::Generic),
1301                                  GR.getPointerSize()));
1302   MachineFunction *MF = I.getParent()->getParent();
1303   GR.assignSPIRVTypeToVReg(GenericPtrTy, Tmp, *MF);
1304   MachineInstrBuilder MIB = buildSpecConstantOp(
1305       I, Tmp, SrcPtr, GR.getSPIRVTypeID(GenericPtrTy),
1306       static_cast<uint32_t>(SPIRV::Opcode::PtrCastToGeneric));
1307   GR.add(MIB.getInstr(), MF, Tmp);
1308   return MIB;
1309 }
1310 
1311 // In SPIR-V address space casting can only happen to and from the Generic
1312 // storage class. We can also only cast Workgroup, CrossWorkgroup, or Function
1313 // pointers to and from Generic pointers. As such, we can convert e.g. from
1314 // Workgroup to Function by going via a Generic pointer as an intermediary. All
1315 // other combinations can only be done by a bitcast, and are probably not safe.
1316 bool SPIRVInstructionSelector::selectAddrSpaceCast(Register ResVReg,
1317                                                    const SPIRVType *ResType,
1318                                                    MachineInstr &I) const {
1319   MachineBasicBlock &BB = *I.getParent();
1320   const DebugLoc &DL = I.getDebugLoc();
1321 
1322   Register SrcPtr = I.getOperand(1).getReg();
1323   SPIRVType *SrcPtrTy = GR.getSPIRVTypeForVReg(SrcPtr);
1324 
1325   // don't generate a cast for a null that may be represented by OpTypeInt
1326   if (SrcPtrTy->getOpcode() != SPIRV::OpTypePointer ||
1327       ResType->getOpcode() != SPIRV::OpTypePointer)
1328     return BuildMI(BB, I, DL, TII.get(TargetOpcode::COPY))
1329         .addDef(ResVReg)
1330         .addUse(SrcPtr)
1331         .constrainAllUses(TII, TRI, RBI);
1332 
1333   SPIRV::StorageClass::StorageClass SrcSC = GR.getPointerStorageClass(SrcPtrTy);
1334   SPIRV::StorageClass::StorageClass DstSC = GR.getPointerStorageClass(ResType);
1335 
1336   if (isASCastInGVar(MRI, ResVReg)) {
1337     // AddrSpaceCast uses within OpVariable and OpConstantComposite instructions
1338     // are expressed by OpSpecConstantOp with an Opcode.
1339     // TODO: maybe insert a check whether the Kernel capability was declared and
1340     // so PtrCastToGeneric/GenericCastToPtr are available.
1341     unsigned SpecOpcode =
1342         DstSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(SrcSC)
1343             ? static_cast<uint32_t>(SPIRV::Opcode::PtrCastToGeneric)
1344             : (SrcSC == SPIRV::StorageClass::Generic &&
1345                        isGenericCastablePtr(DstSC)
1346                    ? static_cast<uint32_t>(SPIRV::Opcode::GenericCastToPtr)
1347                    : 0);
1348     // TODO: OpConstantComposite expects i8*, so we are forced to forget a
1349     // correct value of ResType and use general i8* instead. Maybe this should
1350     // be addressed in the emit-intrinsic step to infer a correct
1351     // OpConstantComposite type.
1352     if (SpecOpcode) {
1353       return buildSpecConstantOp(I, ResVReg, SrcPtr,
1354                                  getUcharPtrTypeReg(I, DstSC), SpecOpcode)
1355           .constrainAllUses(TII, TRI, RBI);
1356     } else if (isGenericCastablePtr(SrcSC) && isGenericCastablePtr(DstSC)) {
1357       MachineInstrBuilder MIB = buildConstGenericPtr(I, SrcPtr, SrcPtrTy);
1358       return MIB.constrainAllUses(TII, TRI, RBI) &&
1359              buildSpecConstantOp(
1360                  I, ResVReg, MIB->getOperand(0).getReg(),
1361                  getUcharPtrTypeReg(I, DstSC),
1362                  static_cast<uint32_t>(SPIRV::Opcode::GenericCastToPtr))
1363                  .constrainAllUses(TII, TRI, RBI);
1364     }
1365   }
1366 
1367   // don't generate a cast between identical storage classes
1368   if (SrcSC == DstSC)
1369     return BuildMI(BB, I, DL, TII.get(TargetOpcode::COPY))
1370         .addDef(ResVReg)
1371         .addUse(SrcPtr)
1372         .constrainAllUses(TII, TRI, RBI);
1373 
1374   // Casting from an eligible pointer to Generic.
1375   if (DstSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(SrcSC))
1376     return selectUnOp(ResVReg, ResType, I, SPIRV::OpPtrCastToGeneric);
1377   // Casting from Generic to an eligible pointer.
1378   if (SrcSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(DstSC))
1379     return selectUnOp(ResVReg, ResType, I, SPIRV::OpGenericCastToPtr);
1380   // Casting between 2 eligible pointers using Generic as an intermediary.
1381   if (isGenericCastablePtr(SrcSC) && isGenericCastablePtr(DstSC)) {
1382     Register Tmp = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1383     SPIRVType *GenericPtrTy = GR.getOrCreateSPIRVPointerType(
1384         GR.getPointeeType(SrcPtrTy), I, TII, SPIRV::StorageClass::Generic);
1385     bool Success = BuildMI(BB, I, DL, TII.get(SPIRV::OpPtrCastToGeneric))
1386                        .addDef(Tmp)
1387                        .addUse(GR.getSPIRVTypeID(GenericPtrTy))
1388                        .addUse(SrcPtr)
1389                        .constrainAllUses(TII, TRI, RBI);
1390     return Success && BuildMI(BB, I, DL, TII.get(SPIRV::OpGenericCastToPtr))
1391                           .addDef(ResVReg)
1392                           .addUse(GR.getSPIRVTypeID(ResType))
1393                           .addUse(Tmp)
1394                           .constrainAllUses(TII, TRI, RBI);
1395   }
1396 
1397   // Check if instructions from the SPV_INTEL_usm_storage_classes extension may
1398   // be applied
1399   if (isUSMStorageClass(SrcSC) && DstSC == SPIRV::StorageClass::CrossWorkgroup)
1400     return selectUnOp(ResVReg, ResType, I,
1401                       SPIRV::OpPtrCastToCrossWorkgroupINTEL);
1402   if (SrcSC == SPIRV::StorageClass::CrossWorkgroup && isUSMStorageClass(DstSC))
1403     return selectUnOp(ResVReg, ResType, I,
1404                       SPIRV::OpCrossWorkgroupCastToPtrINTEL);
1405   if (isUSMStorageClass(SrcSC) && DstSC == SPIRV::StorageClass::Generic)
1406     return selectUnOp(ResVReg, ResType, I, SPIRV::OpPtrCastToGeneric);
1407   if (SrcSC == SPIRV::StorageClass::Generic && isUSMStorageClass(DstSC))
1408     return selectUnOp(ResVReg, ResType, I, SPIRV::OpGenericCastToPtr);
1409 
1410   // Bitcast for pointers requires that the address spaces must match
1411   return false;
1412 }
1413 
1414 static unsigned getFCmpOpcode(unsigned PredNum) {
1415   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1416   switch (Pred) {
1417   case CmpInst::FCMP_OEQ:
1418     return SPIRV::OpFOrdEqual;
1419   case CmpInst::FCMP_OGE:
1420     return SPIRV::OpFOrdGreaterThanEqual;
1421   case CmpInst::FCMP_OGT:
1422     return SPIRV::OpFOrdGreaterThan;
1423   case CmpInst::FCMP_OLE:
1424     return SPIRV::OpFOrdLessThanEqual;
1425   case CmpInst::FCMP_OLT:
1426     return SPIRV::OpFOrdLessThan;
1427   case CmpInst::FCMP_ONE:
1428     return SPIRV::OpFOrdNotEqual;
1429   case CmpInst::FCMP_ORD:
1430     return SPIRV::OpOrdered;
1431   case CmpInst::FCMP_UEQ:
1432     return SPIRV::OpFUnordEqual;
1433   case CmpInst::FCMP_UGE:
1434     return SPIRV::OpFUnordGreaterThanEqual;
1435   case CmpInst::FCMP_UGT:
1436     return SPIRV::OpFUnordGreaterThan;
1437   case CmpInst::FCMP_ULE:
1438     return SPIRV::OpFUnordLessThanEqual;
1439   case CmpInst::FCMP_ULT:
1440     return SPIRV::OpFUnordLessThan;
1441   case CmpInst::FCMP_UNE:
1442     return SPIRV::OpFUnordNotEqual;
1443   case CmpInst::FCMP_UNO:
1444     return SPIRV::OpUnordered;
1445   default:
1446     llvm_unreachable("Unknown predicate type for FCmp");
1447   }
1448 }
1449 
1450 static unsigned getICmpOpcode(unsigned PredNum) {
1451   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1452   switch (Pred) {
1453   case CmpInst::ICMP_EQ:
1454     return SPIRV::OpIEqual;
1455   case CmpInst::ICMP_NE:
1456     return SPIRV::OpINotEqual;
1457   case CmpInst::ICMP_SGE:
1458     return SPIRV::OpSGreaterThanEqual;
1459   case CmpInst::ICMP_SGT:
1460     return SPIRV::OpSGreaterThan;
1461   case CmpInst::ICMP_SLE:
1462     return SPIRV::OpSLessThanEqual;
1463   case CmpInst::ICMP_SLT:
1464     return SPIRV::OpSLessThan;
1465   case CmpInst::ICMP_UGE:
1466     return SPIRV::OpUGreaterThanEqual;
1467   case CmpInst::ICMP_UGT:
1468     return SPIRV::OpUGreaterThan;
1469   case CmpInst::ICMP_ULE:
1470     return SPIRV::OpULessThanEqual;
1471   case CmpInst::ICMP_ULT:
1472     return SPIRV::OpULessThan;
1473   default:
1474     llvm_unreachable("Unknown predicate type for ICmp");
1475   }
1476 }
1477 
1478 static unsigned getPtrCmpOpcode(unsigned Pred) {
1479   switch (static_cast<CmpInst::Predicate>(Pred)) {
1480   case CmpInst::ICMP_EQ:
1481     return SPIRV::OpPtrEqual;
1482   case CmpInst::ICMP_NE:
1483     return SPIRV::OpPtrNotEqual;
1484   default:
1485     llvm_unreachable("Unknown predicate type for pointer comparison");
1486   }
1487 }
1488 
1489 // Return the logical operation, or abort if none exists.
1490 static unsigned getBoolCmpOpcode(unsigned PredNum) {
1491   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1492   switch (Pred) {
1493   case CmpInst::ICMP_EQ:
1494     return SPIRV::OpLogicalEqual;
1495   case CmpInst::ICMP_NE:
1496     return SPIRV::OpLogicalNotEqual;
1497   default:
1498     llvm_unreachable("Unknown predicate type for Bool comparison");
1499   }
1500 }
1501 
1502 static APFloat getZeroFP(const Type *LLVMFloatTy) {
1503   if (!LLVMFloatTy)
1504     return APFloat::getZero(APFloat::IEEEsingle());
1505   switch (LLVMFloatTy->getScalarType()->getTypeID()) {
1506   case Type::HalfTyID:
1507     return APFloat::getZero(APFloat::IEEEhalf());
1508   default:
1509   case Type::FloatTyID:
1510     return APFloat::getZero(APFloat::IEEEsingle());
1511   case Type::DoubleTyID:
1512     return APFloat::getZero(APFloat::IEEEdouble());
1513   }
1514 }
1515 
1516 static APFloat getOneFP(const Type *LLVMFloatTy) {
1517   if (!LLVMFloatTy)
1518     return APFloat::getOne(APFloat::IEEEsingle());
1519   switch (LLVMFloatTy->getScalarType()->getTypeID()) {
1520   case Type::HalfTyID:
1521     return APFloat::getOne(APFloat::IEEEhalf());
1522   default:
1523   case Type::FloatTyID:
1524     return APFloat::getOne(APFloat::IEEEsingle());
1525   case Type::DoubleTyID:
1526     return APFloat::getOne(APFloat::IEEEdouble());
1527   }
1528 }
1529 
1530 bool SPIRVInstructionSelector::selectAnyOrAll(Register ResVReg,
1531                                               const SPIRVType *ResType,
1532                                               MachineInstr &I,
1533                                               unsigned OpAnyOrAll) const {
1534   assert(I.getNumOperands() == 3);
1535   assert(I.getOperand(2).isReg());
1536   MachineBasicBlock &BB = *I.getParent();
1537   Register InputRegister = I.getOperand(2).getReg();
1538   SPIRVType *InputType = GR.getSPIRVTypeForVReg(InputRegister);
1539 
1540   if (!InputType)
1541     report_fatal_error("Input Type could not be determined.");
1542 
1543   bool IsBoolTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeBool);
1544   bool IsVectorTy = InputType->getOpcode() == SPIRV::OpTypeVector;
1545   if (IsBoolTy && !IsVectorTy) {
1546     assert(ResVReg == I.getOperand(0).getReg());
1547     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1548                    TII.get(TargetOpcode::COPY))
1549         .addDef(ResVReg)
1550         .addUse(InputRegister)
1551         .constrainAllUses(TII, TRI, RBI);
1552   }
1553 
1554   bool IsFloatTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeFloat);
1555   unsigned SpirvNotEqualId =
1556       IsFloatTy ? SPIRV::OpFOrdNotEqual : SPIRV::OpINotEqual;
1557   SPIRVType *SpvBoolScalarTy = GR.getOrCreateSPIRVBoolType(I, TII);
1558   SPIRVType *SpvBoolTy = SpvBoolScalarTy;
1559   Register NotEqualReg = ResVReg;
1560 
1561   if (IsVectorTy) {
1562     NotEqualReg = IsBoolTy ? InputRegister
1563                            : MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1564     const unsigned NumElts = InputType->getOperand(2).getImm();
1565     SpvBoolTy = GR.getOrCreateSPIRVVectorType(SpvBoolTy, NumElts, I, TII);
1566   }
1567 
1568   if (!IsBoolTy) {
1569     Register ConstZeroReg =
1570         IsFloatTy ? buildZerosValF(InputType, I) : buildZerosVal(InputType, I);
1571 
1572     BuildMI(BB, I, I.getDebugLoc(), TII.get(SpirvNotEqualId))
1573         .addDef(NotEqualReg)
1574         .addUse(GR.getSPIRVTypeID(SpvBoolTy))
1575         .addUse(InputRegister)
1576         .addUse(ConstZeroReg)
1577         .constrainAllUses(TII, TRI, RBI);
1578   }
1579 
1580   if (!IsVectorTy)
1581     return true;
1582 
1583   return BuildMI(BB, I, I.getDebugLoc(), TII.get(OpAnyOrAll))
1584       .addDef(ResVReg)
1585       .addUse(GR.getSPIRVTypeID(SpvBoolScalarTy))
1586       .addUse(NotEqualReg)
1587       .constrainAllUses(TII, TRI, RBI);
1588 }
1589 
1590 bool SPIRVInstructionSelector::selectAll(Register ResVReg,
1591                                          const SPIRVType *ResType,
1592                                          MachineInstr &I) const {
1593   return selectAnyOrAll(ResVReg, ResType, I, SPIRV::OpAll);
1594 }
1595 
1596 bool SPIRVInstructionSelector::selectAny(Register ResVReg,
1597                                          const SPIRVType *ResType,
1598                                          MachineInstr &I) const {
1599   return selectAnyOrAll(ResVReg, ResType, I, SPIRV::OpAny);
1600 }
1601 
1602 // Select the OpDot instruction for the given float dot
1603 bool SPIRVInstructionSelector::selectFloatDot(Register ResVReg,
1604                                               const SPIRVType *ResType,
1605                                               MachineInstr &I) const {
1606   assert(I.getNumOperands() == 4);
1607   assert(I.getOperand(2).isReg());
1608   assert(I.getOperand(3).isReg());
1609 
1610   [[maybe_unused]] SPIRVType *VecType =
1611       GR.getSPIRVTypeForVReg(I.getOperand(2).getReg());
1612 
1613   assert(VecType->getOpcode() == SPIRV::OpTypeVector &&
1614          GR.getScalarOrVectorComponentCount(VecType) > 1 &&
1615          "dot product requires a vector of at least 2 components");
1616 
1617   [[maybe_unused]] SPIRVType *EltType =
1618       GR.getSPIRVTypeForVReg(VecType->getOperand(1).getReg());
1619 
1620   assert(EltType->getOpcode() == SPIRV::OpTypeFloat);
1621 
1622   MachineBasicBlock &BB = *I.getParent();
1623   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpDot))
1624       .addDef(ResVReg)
1625       .addUse(GR.getSPIRVTypeID(ResType))
1626       .addUse(I.getOperand(2).getReg())
1627       .addUse(I.getOperand(3).getReg())
1628       .constrainAllUses(TII, TRI, RBI);
1629 }
1630 
1631 // Since pre-1.6 SPIRV has no integer dot implementation,
1632 // expand by piecewise multiplying and adding the results
1633 bool SPIRVInstructionSelector::selectIntegerDot(Register ResVReg,
1634                                                 const SPIRVType *ResType,
1635                                                 MachineInstr &I) const {
1636   assert(I.getNumOperands() == 4);
1637   assert(I.getOperand(2).isReg());
1638   assert(I.getOperand(3).isReg());
1639   MachineBasicBlock &BB = *I.getParent();
1640 
1641   // Multiply the vectors, then sum the results
1642   Register Vec0 = I.getOperand(2).getReg();
1643   Register Vec1 = I.getOperand(3).getReg();
1644   Register TmpVec = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1645   SPIRVType *VecType = GR.getSPIRVTypeForVReg(Vec0);
1646 
1647   bool Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIMulV))
1648                     .addDef(TmpVec)
1649                     .addUse(GR.getSPIRVTypeID(VecType))
1650                     .addUse(Vec0)
1651                     .addUse(Vec1)
1652                     .constrainAllUses(TII, TRI, RBI);
1653 
1654   assert(VecType->getOpcode() == SPIRV::OpTypeVector &&
1655          GR.getScalarOrVectorComponentCount(VecType) > 1 &&
1656          "dot product requires a vector of at least 2 components");
1657 
1658   Register Res = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1659   Result |= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1660                 .addDef(Res)
1661                 .addUse(GR.getSPIRVTypeID(ResType))
1662                 .addUse(TmpVec)
1663                 .addImm(0)
1664                 .constrainAllUses(TII, TRI, RBI);
1665 
1666   for (unsigned i = 1; i < GR.getScalarOrVectorComponentCount(VecType); i++) {
1667     Register Elt = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1668 
1669     Result |=
1670         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1671             .addDef(Elt)
1672             .addUse(GR.getSPIRVTypeID(ResType))
1673             .addUse(TmpVec)
1674             .addImm(i)
1675             .constrainAllUses(TII, TRI, RBI);
1676 
1677     Register Sum = i < GR.getScalarOrVectorComponentCount(VecType) - 1
1678                        ? MRI->createVirtualRegister(&SPIRV::IDRegClass)
1679                        : ResVReg;
1680 
1681     Result |= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIAddS))
1682                   .addDef(Sum)
1683                   .addUse(GR.getSPIRVTypeID(ResType))
1684                   .addUse(Res)
1685                   .addUse(Elt)
1686                   .constrainAllUses(TII, TRI, RBI);
1687     Res = Sum;
1688   }
1689 
1690   return Result;
1691 }
1692 
1693 /// Transform saturate(x) to clamp(x, 0.0f, 1.0f) as SPIRV
1694 /// does not have a saturate builtin.
1695 bool SPIRVInstructionSelector::selectSaturate(Register ResVReg,
1696                                               const SPIRVType *ResType,
1697                                               MachineInstr &I) const {
1698   assert(I.getNumOperands() == 3);
1699   assert(I.getOperand(2).isReg());
1700   MachineBasicBlock &BB = *I.getParent();
1701   Register VZero = buildZerosValF(ResType, I);
1702   Register VOne = buildOnesValF(ResType, I);
1703 
1704   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
1705       .addDef(ResVReg)
1706       .addUse(GR.getSPIRVTypeID(ResType))
1707       .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
1708       .addImm(GL::FClamp)
1709       .addUse(I.getOperand(2).getReg())
1710       .addUse(VZero)
1711       .addUse(VOne)
1712       .constrainAllUses(TII, TRI, RBI);
1713 }
1714 
1715 bool SPIRVInstructionSelector::selectSign(Register ResVReg,
1716                                           const SPIRVType *ResType,
1717                                           MachineInstr &I) const {
1718   assert(I.getNumOperands() == 3);
1719   assert(I.getOperand(2).isReg());
1720   MachineBasicBlock &BB = *I.getParent();
1721   Register InputRegister = I.getOperand(2).getReg();
1722   SPIRVType *InputType = GR.getSPIRVTypeForVReg(InputRegister);
1723   auto &DL = I.getDebugLoc();
1724 
1725   if (!InputType)
1726     report_fatal_error("Input Type could not be determined.");
1727 
1728   bool IsFloatTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeFloat);
1729 
1730   unsigned SignBitWidth = GR.getScalarOrVectorBitWidth(InputType);
1731   unsigned ResBitWidth = GR.getScalarOrVectorBitWidth(ResType);
1732 
1733   bool NeedsConversion = IsFloatTy || SignBitWidth != ResBitWidth;
1734 
1735   auto SignOpcode = IsFloatTy ? GL::FSign : GL::SSign;
1736   Register SignReg = NeedsConversion
1737                          ? MRI->createVirtualRegister(&SPIRV::IDRegClass)
1738                          : ResVReg;
1739 
1740   bool Result =
1741       BuildMI(BB, I, DL, TII.get(SPIRV::OpExtInst))
1742           .addDef(SignReg)
1743           .addUse(GR.getSPIRVTypeID(InputType))
1744           .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
1745           .addImm(SignOpcode)
1746           .addUse(InputRegister)
1747           .constrainAllUses(TII, TRI, RBI);
1748 
1749   if (NeedsConversion) {
1750     auto ConvertOpcode = IsFloatTy ? SPIRV::OpConvertFToS : SPIRV::OpSConvert;
1751     Result |= BuildMI(*I.getParent(), I, DL, TII.get(ConvertOpcode))
1752                   .addDef(ResVReg)
1753                   .addUse(GR.getSPIRVTypeID(ResType))
1754                   .addUse(SignReg)
1755                   .constrainAllUses(TII, TRI, RBI);
1756   }
1757 
1758   return Result;
1759 }
1760 
1761 bool SPIRVInstructionSelector::selectBitreverse(Register ResVReg,
1762                                                 const SPIRVType *ResType,
1763                                                 MachineInstr &I) const {
1764   MachineBasicBlock &BB = *I.getParent();
1765   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpBitReverse))
1766       .addDef(ResVReg)
1767       .addUse(GR.getSPIRVTypeID(ResType))
1768       .addUse(I.getOperand(1).getReg())
1769       .constrainAllUses(TII, TRI, RBI);
1770 }
1771 
1772 bool SPIRVInstructionSelector::selectFreeze(Register ResVReg,
1773                                             const SPIRVType *ResType,
1774                                             MachineInstr &I) const {
1775   // There is no way to implement `freeze` correctly without support on SPIR-V
1776   // standard side, but we may at least address a simple (static) case when
1777   // undef/poison value presence is obvious. The main benefit of even
1778   // incomplete `freeze` support is preventing of translation from crashing due
1779   // to lack of support on legalization and instruction selection steps.
1780   if (!I.getOperand(0).isReg() || !I.getOperand(1).isReg())
1781     return false;
1782   Register OpReg = I.getOperand(1).getReg();
1783   if (MachineInstr *Def = MRI->getVRegDef(OpReg)) {
1784     Register Reg;
1785     switch (Def->getOpcode()) {
1786     case SPIRV::ASSIGN_TYPE:
1787       if (MachineInstr *AssignToDef =
1788               MRI->getVRegDef(Def->getOperand(1).getReg())) {
1789         if (AssignToDef->getOpcode() == TargetOpcode::G_IMPLICIT_DEF)
1790           Reg = Def->getOperand(2).getReg();
1791       }
1792       break;
1793     case SPIRV::OpUndef:
1794       Reg = Def->getOperand(1).getReg();
1795       break;
1796     }
1797     unsigned DestOpCode;
1798     if (Reg.isValid()) {
1799       DestOpCode = SPIRV::OpConstantNull;
1800     } else {
1801       DestOpCode = TargetOpcode::COPY;
1802       Reg = OpReg;
1803     }
1804     return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(DestOpCode))
1805         .addDef(I.getOperand(0).getReg())
1806         .addUse(Reg)
1807         .constrainAllUses(TII, TRI, RBI);
1808   }
1809   return false;
1810 }
1811 
1812 static unsigned getArrayComponentCount(MachineRegisterInfo *MRI,
1813                                        const SPIRVType *ResType) {
1814   Register OpReg = ResType->getOperand(2).getReg();
1815   SPIRVType *OpDef = MRI->getVRegDef(OpReg);
1816   if (!OpDef)
1817     return 0;
1818   if (OpDef->getOpcode() == SPIRV::ASSIGN_TYPE &&
1819       OpDef->getOperand(1).isReg()) {
1820     if (SPIRVType *RefDef = MRI->getVRegDef(OpDef->getOperand(1).getReg()))
1821       OpDef = RefDef;
1822   }
1823   unsigned N = OpDef->getOpcode() == TargetOpcode::G_CONSTANT
1824                    ? OpDef->getOperand(1).getCImm()->getValue().getZExtValue()
1825                    : 0;
1826   return N;
1827 }
1828 
1829 // Return true if the type represents a constant register
1830 static bool isConstReg(MachineRegisterInfo *MRI, SPIRVType *OpDef,
1831                        SmallPtrSet<SPIRVType *, 4> &Visited) {
1832   if (OpDef->getOpcode() == SPIRV::ASSIGN_TYPE &&
1833       OpDef->getOperand(1).isReg()) {
1834     if (SPIRVType *RefDef = MRI->getVRegDef(OpDef->getOperand(1).getReg()))
1835       OpDef = RefDef;
1836   }
1837 
1838   if (Visited.contains(OpDef))
1839     return true;
1840   Visited.insert(OpDef);
1841 
1842   unsigned Opcode = OpDef->getOpcode();
1843   switch (Opcode) {
1844   case TargetOpcode::G_CONSTANT:
1845   case TargetOpcode::G_FCONSTANT:
1846     return true;
1847   case TargetOpcode::G_INTRINSIC:
1848   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
1849   case TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS:
1850     return cast<GIntrinsic>(*OpDef).getIntrinsicID() ==
1851            Intrinsic::spv_const_composite;
1852   case TargetOpcode::G_BUILD_VECTOR:
1853   case TargetOpcode::G_SPLAT_VECTOR: {
1854     for (unsigned i = OpDef->getNumExplicitDefs(); i < OpDef->getNumOperands();
1855          i++) {
1856       SPIRVType *OpNestedDef =
1857           OpDef->getOperand(i).isReg()
1858               ? MRI->getVRegDef(OpDef->getOperand(i).getReg())
1859               : nullptr;
1860       if (OpNestedDef && !isConstReg(MRI, OpNestedDef, Visited))
1861         return false;
1862     }
1863     return true;
1864   }
1865   }
1866   return false;
1867 }
1868 
1869 // Return true if the virtual register represents a constant
1870 static bool isConstReg(MachineRegisterInfo *MRI, Register OpReg) {
1871   SmallPtrSet<SPIRVType *, 4> Visited;
1872   if (SPIRVType *OpDef = MRI->getVRegDef(OpReg))
1873     return isConstReg(MRI, OpDef, Visited);
1874   return false;
1875 }
1876 
1877 bool SPIRVInstructionSelector::selectBuildVector(Register ResVReg,
1878                                                  const SPIRVType *ResType,
1879                                                  MachineInstr &I) const {
1880   unsigned N = 0;
1881   if (ResType->getOpcode() == SPIRV::OpTypeVector)
1882     N = GR.getScalarOrVectorComponentCount(ResType);
1883   else if (ResType->getOpcode() == SPIRV::OpTypeArray)
1884     N = getArrayComponentCount(MRI, ResType);
1885   else
1886     report_fatal_error("Cannot select G_BUILD_VECTOR with a non-vector result");
1887   if (I.getNumExplicitOperands() - I.getNumExplicitDefs() != N)
1888     report_fatal_error("G_BUILD_VECTOR and the result type are inconsistent");
1889 
1890   // check if we may construct a constant vector
1891   bool IsConst = true;
1892   for (unsigned i = I.getNumExplicitDefs();
1893        i < I.getNumExplicitOperands() && IsConst; ++i)
1894     if (!isConstReg(MRI, I.getOperand(i).getReg()))
1895       IsConst = false;
1896 
1897   if (!IsConst && N < 2)
1898     report_fatal_error(
1899         "There must be at least two constituent operands in a vector");
1900 
1901   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
1902                      TII.get(IsConst ? SPIRV::OpConstantComposite
1903                                      : SPIRV::OpCompositeConstruct))
1904                  .addDef(ResVReg)
1905                  .addUse(GR.getSPIRVTypeID(ResType));
1906   for (unsigned i = I.getNumExplicitDefs(); i < I.getNumExplicitOperands(); ++i)
1907     MIB.addUse(I.getOperand(i).getReg());
1908   return MIB.constrainAllUses(TII, TRI, RBI);
1909 }
1910 
1911 bool SPIRVInstructionSelector::selectSplatVector(Register ResVReg,
1912                                                  const SPIRVType *ResType,
1913                                                  MachineInstr &I) const {
1914   unsigned N = 0;
1915   if (ResType->getOpcode() == SPIRV::OpTypeVector)
1916     N = GR.getScalarOrVectorComponentCount(ResType);
1917   else if (ResType->getOpcode() == SPIRV::OpTypeArray)
1918     N = getArrayComponentCount(MRI, ResType);
1919   else
1920     report_fatal_error("Cannot select G_SPLAT_VECTOR with a non-vector result");
1921 
1922   unsigned OpIdx = I.getNumExplicitDefs();
1923   if (!I.getOperand(OpIdx).isReg())
1924     report_fatal_error("Unexpected argument in G_SPLAT_VECTOR");
1925 
1926   // check if we may construct a constant vector
1927   Register OpReg = I.getOperand(OpIdx).getReg();
1928   bool IsConst = isConstReg(MRI, OpReg);
1929 
1930   if (!IsConst && N < 2)
1931     report_fatal_error(
1932         "There must be at least two constituent operands in a vector");
1933 
1934   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
1935                      TII.get(IsConst ? SPIRV::OpConstantComposite
1936                                      : SPIRV::OpCompositeConstruct))
1937                  .addDef(ResVReg)
1938                  .addUse(GR.getSPIRVTypeID(ResType));
1939   for (unsigned i = 0; i < N; ++i)
1940     MIB.addUse(OpReg);
1941   return MIB.constrainAllUses(TII, TRI, RBI);
1942 }
1943 
1944 bool SPIRVInstructionSelector::selectCmp(Register ResVReg,
1945                                          const SPIRVType *ResType,
1946                                          unsigned CmpOpc,
1947                                          MachineInstr &I) const {
1948   Register Cmp0 = I.getOperand(2).getReg();
1949   Register Cmp1 = I.getOperand(3).getReg();
1950   assert(GR.getSPIRVTypeForVReg(Cmp0)->getOpcode() ==
1951              GR.getSPIRVTypeForVReg(Cmp1)->getOpcode() &&
1952          "CMP operands should have the same type");
1953   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(CmpOpc))
1954       .addDef(ResVReg)
1955       .addUse(GR.getSPIRVTypeID(ResType))
1956       .addUse(Cmp0)
1957       .addUse(Cmp1)
1958       .constrainAllUses(TII, TRI, RBI);
1959 }
1960 
1961 bool SPIRVInstructionSelector::selectICmp(Register ResVReg,
1962                                           const SPIRVType *ResType,
1963                                           MachineInstr &I) const {
1964   auto Pred = I.getOperand(1).getPredicate();
1965   unsigned CmpOpc;
1966 
1967   Register CmpOperand = I.getOperand(2).getReg();
1968   if (GR.isScalarOfType(CmpOperand, SPIRV::OpTypePointer))
1969     CmpOpc = getPtrCmpOpcode(Pred);
1970   else if (GR.isScalarOrVectorOfType(CmpOperand, SPIRV::OpTypeBool))
1971     CmpOpc = getBoolCmpOpcode(Pred);
1972   else
1973     CmpOpc = getICmpOpcode(Pred);
1974   return selectCmp(ResVReg, ResType, CmpOpc, I);
1975 }
1976 
1977 void SPIRVInstructionSelector::renderFImm64(MachineInstrBuilder &MIB,
1978                                             const MachineInstr &I,
1979                                             int OpIdx) const {
1980   assert(I.getOpcode() == TargetOpcode::G_FCONSTANT && OpIdx == -1 &&
1981          "Expected G_FCONSTANT");
1982   const ConstantFP *FPImm = I.getOperand(1).getFPImm();
1983   addNumImm(FPImm->getValueAPF().bitcastToAPInt(), MIB);
1984 }
1985 
1986 void SPIRVInstructionSelector::renderImm32(MachineInstrBuilder &MIB,
1987                                            const MachineInstr &I,
1988                                            int OpIdx) const {
1989   assert(I.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
1990          "Expected G_CONSTANT");
1991   addNumImm(I.getOperand(1).getCImm()->getValue(), MIB);
1992 }
1993 
1994 Register
1995 SPIRVInstructionSelector::buildI32Constant(uint32_t Val, MachineInstr &I,
1996                                            const SPIRVType *ResType) const {
1997   Type *LLVMTy = IntegerType::get(GR.CurMF->getFunction().getContext(), 32);
1998   const SPIRVType *SpvI32Ty =
1999       ResType ? ResType : GR.getOrCreateSPIRVIntegerType(32, I, TII);
2000   // Find a constant in DT or build a new one.
2001   auto ConstInt = ConstantInt::get(LLVMTy, Val);
2002   Register NewReg = GR.find(ConstInt, GR.CurMF);
2003   if (!NewReg.isValid()) {
2004     NewReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
2005     GR.add(ConstInt, GR.CurMF, NewReg);
2006     MachineInstr *MI;
2007     MachineBasicBlock &BB = *I.getParent();
2008     if (Val == 0) {
2009       MI = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
2010                .addDef(NewReg)
2011                .addUse(GR.getSPIRVTypeID(SpvI32Ty));
2012     } else {
2013       MI = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantI))
2014                .addDef(NewReg)
2015                .addUse(GR.getSPIRVTypeID(SpvI32Ty))
2016                .addImm(APInt(32, Val).getZExtValue());
2017     }
2018     constrainSelectedInstRegOperands(*MI, TII, TRI, RBI);
2019   }
2020   return NewReg;
2021 }
2022 
2023 bool SPIRVInstructionSelector::selectFCmp(Register ResVReg,
2024                                           const SPIRVType *ResType,
2025                                           MachineInstr &I) const {
2026   unsigned CmpOp = getFCmpOpcode(I.getOperand(1).getPredicate());
2027   return selectCmp(ResVReg, ResType, CmpOp, I);
2028 }
2029 
2030 Register SPIRVInstructionSelector::buildZerosVal(const SPIRVType *ResType,
2031                                                  MachineInstr &I) const {
2032   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
2033   bool ZeroAsNull = STI.isOpenCLEnv();
2034   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2035     return GR.getOrCreateConstVector(0UL, I, ResType, TII, ZeroAsNull);
2036   return GR.getOrCreateConstInt(0, I, ResType, TII, ZeroAsNull);
2037 }
2038 
2039 Register SPIRVInstructionSelector::buildZerosValF(const SPIRVType *ResType,
2040                                                   MachineInstr &I) const {
2041   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
2042   bool ZeroAsNull = STI.isOpenCLEnv();
2043   APFloat VZero = getZeroFP(GR.getTypeForSPIRVType(ResType));
2044   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2045     return GR.getOrCreateConstVector(VZero, I, ResType, TII, ZeroAsNull);
2046   return GR.getOrCreateConstFP(VZero, I, ResType, TII, ZeroAsNull);
2047 }
2048 
2049 Register SPIRVInstructionSelector::buildOnesValF(const SPIRVType *ResType,
2050                                                  MachineInstr &I) const {
2051   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
2052   bool ZeroAsNull = STI.isOpenCLEnv();
2053   APFloat VOne = getOneFP(GR.getTypeForSPIRVType(ResType));
2054   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2055     return GR.getOrCreateConstVector(VOne, I, ResType, TII, ZeroAsNull);
2056   return GR.getOrCreateConstFP(VOne, I, ResType, TII, ZeroAsNull);
2057 }
2058 
2059 Register SPIRVInstructionSelector::buildOnesVal(bool AllOnes,
2060                                                 const SPIRVType *ResType,
2061                                                 MachineInstr &I) const {
2062   unsigned BitWidth = GR.getScalarOrVectorBitWidth(ResType);
2063   APInt One =
2064       AllOnes ? APInt::getAllOnes(BitWidth) : APInt::getOneBitSet(BitWidth, 0);
2065   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2066     return GR.getOrCreateConstVector(One.getZExtValue(), I, ResType, TII);
2067   return GR.getOrCreateConstInt(One.getZExtValue(), I, ResType, TII);
2068 }
2069 
2070 bool SPIRVInstructionSelector::selectSelect(Register ResVReg,
2071                                             const SPIRVType *ResType,
2072                                             MachineInstr &I,
2073                                             bool IsSigned) const {
2074   // To extend a bool, we need to use OpSelect between constants.
2075   Register ZeroReg = buildZerosVal(ResType, I);
2076   Register OneReg = buildOnesVal(IsSigned, ResType, I);
2077   bool IsScalarBool =
2078       GR.isScalarOfType(I.getOperand(1).getReg(), SPIRV::OpTypeBool);
2079   unsigned Opcode =
2080       IsScalarBool ? SPIRV::OpSelectSISCond : SPIRV::OpSelectSIVCond;
2081   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
2082       .addDef(ResVReg)
2083       .addUse(GR.getSPIRVTypeID(ResType))
2084       .addUse(I.getOperand(1).getReg())
2085       .addUse(OneReg)
2086       .addUse(ZeroReg)
2087       .constrainAllUses(TII, TRI, RBI);
2088 }
2089 
2090 bool SPIRVInstructionSelector::selectIToF(Register ResVReg,
2091                                           const SPIRVType *ResType,
2092                                           MachineInstr &I, bool IsSigned,
2093                                           unsigned Opcode) const {
2094   Register SrcReg = I.getOperand(1).getReg();
2095   // We can convert bool value directly to float type without OpConvert*ToF,
2096   // however the translator generates OpSelect+OpConvert*ToF, so we do the same.
2097   if (GR.isScalarOrVectorOfType(I.getOperand(1).getReg(), SPIRV::OpTypeBool)) {
2098     unsigned BitWidth = GR.getScalarOrVectorBitWidth(ResType);
2099     SPIRVType *TmpType = GR.getOrCreateSPIRVIntegerType(BitWidth, I, TII);
2100     if (ResType->getOpcode() == SPIRV::OpTypeVector) {
2101       const unsigned NumElts = ResType->getOperand(2).getImm();
2102       TmpType = GR.getOrCreateSPIRVVectorType(TmpType, NumElts, I, TII);
2103     }
2104     SrcReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2105     selectSelect(SrcReg, TmpType, I, false);
2106   }
2107   return selectUnOpWithSrc(ResVReg, ResType, I, SrcReg, Opcode);
2108 }
2109 
2110 bool SPIRVInstructionSelector::selectExt(Register ResVReg,
2111                                          const SPIRVType *ResType,
2112                                          MachineInstr &I, bool IsSigned) const {
2113   Register SrcReg = I.getOperand(1).getReg();
2114   if (GR.isScalarOrVectorOfType(SrcReg, SPIRV::OpTypeBool))
2115     return selectSelect(ResVReg, ResType, I, IsSigned);
2116 
2117   SPIRVType *SrcType = GR.getSPIRVTypeForVReg(SrcReg);
2118   if (SrcType == ResType) {
2119     const TargetRegisterClass *DstRC = MRI->getRegClassOrNull(ResVReg);
2120     const TargetRegisterClass *SrcRC = MRI->getRegClassOrNull(SrcReg);
2121     if (DstRC != SrcRC && SrcRC)
2122       MRI->setRegClass(ResVReg, SrcRC);
2123     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
2124                    TII.get(TargetOpcode::COPY))
2125         .addDef(ResVReg)
2126         .addUse(SrcReg)
2127         .constrainAllUses(TII, TRI, RBI);
2128   }
2129 
2130   unsigned Opcode = IsSigned ? SPIRV::OpSConvert : SPIRV::OpUConvert;
2131   return selectUnOp(ResVReg, ResType, I, Opcode);
2132 }
2133 
2134 bool SPIRVInstructionSelector::selectIntToBool(Register IntReg,
2135                                                Register ResVReg,
2136                                                MachineInstr &I,
2137                                                const SPIRVType *IntTy,
2138                                                const SPIRVType *BoolTy) const {
2139   // To truncate to a bool, we use OpBitwiseAnd 1 and OpINotEqual to zero.
2140   Register BitIntReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2141   bool IsVectorTy = IntTy->getOpcode() == SPIRV::OpTypeVector;
2142   unsigned Opcode = IsVectorTy ? SPIRV::OpBitwiseAndV : SPIRV::OpBitwiseAndS;
2143   Register Zero = buildZerosVal(IntTy, I);
2144   Register One = buildOnesVal(false, IntTy, I);
2145   MachineBasicBlock &BB = *I.getParent();
2146   BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2147       .addDef(BitIntReg)
2148       .addUse(GR.getSPIRVTypeID(IntTy))
2149       .addUse(IntReg)
2150       .addUse(One)
2151       .constrainAllUses(TII, TRI, RBI);
2152   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpINotEqual))
2153       .addDef(ResVReg)
2154       .addUse(GR.getSPIRVTypeID(BoolTy))
2155       .addUse(BitIntReg)
2156       .addUse(Zero)
2157       .constrainAllUses(TII, TRI, RBI);
2158 }
2159 
2160 bool SPIRVInstructionSelector::selectTrunc(Register ResVReg,
2161                                            const SPIRVType *ResType,
2162                                            MachineInstr &I) const {
2163   Register IntReg = I.getOperand(1).getReg();
2164   const SPIRVType *ArgType = GR.getSPIRVTypeForVReg(IntReg);
2165   if (GR.isScalarOrVectorOfType(ResVReg, SPIRV::OpTypeBool))
2166     return selectIntToBool(IntReg, ResVReg, I, ArgType, ResType);
2167   if (ArgType == ResType) {
2168     const TargetRegisterClass *DstRC = MRI->getRegClassOrNull(ResVReg);
2169     const TargetRegisterClass *SrcRC = MRI->getRegClassOrNull(IntReg);
2170     if (DstRC != SrcRC && SrcRC)
2171       MRI->setRegClass(ResVReg, SrcRC);
2172     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
2173                    TII.get(TargetOpcode::COPY))
2174         .addDef(ResVReg)
2175         .addUse(IntReg)
2176         .constrainAllUses(TII, TRI, RBI);
2177   }
2178   bool IsSigned = GR.isScalarOrVectorSigned(ResType);
2179   unsigned Opcode = IsSigned ? SPIRV::OpSConvert : SPIRV::OpUConvert;
2180   return selectUnOp(ResVReg, ResType, I, Opcode);
2181 }
2182 
2183 bool SPIRVInstructionSelector::selectConst(Register ResVReg,
2184                                            const SPIRVType *ResType,
2185                                            const APInt &Imm,
2186                                            MachineInstr &I) const {
2187   unsigned TyOpcode = ResType->getOpcode();
2188   assert(TyOpcode != SPIRV::OpTypePointer || Imm.isZero());
2189   MachineBasicBlock &BB = *I.getParent();
2190   if ((TyOpcode == SPIRV::OpTypePointer || TyOpcode == SPIRV::OpTypeEvent) &&
2191       Imm.isZero())
2192     return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
2193         .addDef(ResVReg)
2194         .addUse(GR.getSPIRVTypeID(ResType))
2195         .constrainAllUses(TII, TRI, RBI);
2196   if (TyOpcode == SPIRV::OpTypeInt) {
2197     assert(Imm.getBitWidth() <= 64 && "Unsupported integer width!");
2198     Register Reg = GR.getOrCreateConstInt(Imm.getZExtValue(), I, ResType, TII);
2199     if (Reg == ResVReg)
2200       return true;
2201     return BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY))
2202         .addDef(ResVReg)
2203         .addUse(Reg)
2204         .constrainAllUses(TII, TRI, RBI);
2205   }
2206   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantI))
2207                  .addDef(ResVReg)
2208                  .addUse(GR.getSPIRVTypeID(ResType));
2209   // <=32-bit integers should be caught by the sdag pattern.
2210   assert(Imm.getBitWidth() > 32);
2211   addNumImm(Imm, MIB);
2212   return MIB.constrainAllUses(TII, TRI, RBI);
2213 }
2214 
2215 bool SPIRVInstructionSelector::selectOpUndef(Register ResVReg,
2216                                              const SPIRVType *ResType,
2217                                              MachineInstr &I) const {
2218   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpUndef))
2219       .addDef(ResVReg)
2220       .addUse(GR.getSPIRVTypeID(ResType))
2221       .constrainAllUses(TII, TRI, RBI);
2222 }
2223 
2224 static bool isImm(const MachineOperand &MO, MachineRegisterInfo *MRI) {
2225   assert(MO.isReg());
2226   const SPIRVType *TypeInst = MRI->getVRegDef(MO.getReg());
2227   if (TypeInst->getOpcode() == SPIRV::ASSIGN_TYPE) {
2228     assert(TypeInst->getOperand(1).isReg());
2229     MachineInstr *ImmInst = MRI->getVRegDef(TypeInst->getOperand(1).getReg());
2230     return ImmInst->getOpcode() == TargetOpcode::G_CONSTANT;
2231   }
2232   return TypeInst->getOpcode() == SPIRV::OpConstantI;
2233 }
2234 
2235 static int64_t foldImm(const MachineOperand &MO, MachineRegisterInfo *MRI) {
2236   const SPIRVType *TypeInst = MRI->getVRegDef(MO.getReg());
2237   if (TypeInst->getOpcode() == SPIRV::OpConstantI)
2238     return TypeInst->getOperand(2).getImm();
2239   MachineInstr *ImmInst = MRI->getVRegDef(TypeInst->getOperand(1).getReg());
2240   assert(ImmInst->getOpcode() == TargetOpcode::G_CONSTANT);
2241   return ImmInst->getOperand(1).getCImm()->getZExtValue();
2242 }
2243 
2244 bool SPIRVInstructionSelector::selectInsertVal(Register ResVReg,
2245                                                const SPIRVType *ResType,
2246                                                MachineInstr &I) const {
2247   MachineBasicBlock &BB = *I.getParent();
2248   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeInsert))
2249                  .addDef(ResVReg)
2250                  .addUse(GR.getSPIRVTypeID(ResType))
2251                  // object to insert
2252                  .addUse(I.getOperand(3).getReg())
2253                  // composite to insert into
2254                  .addUse(I.getOperand(2).getReg());
2255   for (unsigned i = 4; i < I.getNumOperands(); i++)
2256     MIB.addImm(foldImm(I.getOperand(i), MRI));
2257   return MIB.constrainAllUses(TII, TRI, RBI);
2258 }
2259 
2260 bool SPIRVInstructionSelector::selectExtractVal(Register ResVReg,
2261                                                 const SPIRVType *ResType,
2262                                                 MachineInstr &I) const {
2263   MachineBasicBlock &BB = *I.getParent();
2264   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
2265                  .addDef(ResVReg)
2266                  .addUse(GR.getSPIRVTypeID(ResType))
2267                  .addUse(I.getOperand(2).getReg());
2268   for (unsigned i = 3; i < I.getNumOperands(); i++)
2269     MIB.addImm(foldImm(I.getOperand(i), MRI));
2270   return MIB.constrainAllUses(TII, TRI, RBI);
2271 }
2272 
2273 bool SPIRVInstructionSelector::selectInsertElt(Register ResVReg,
2274                                                const SPIRVType *ResType,
2275                                                MachineInstr &I) const {
2276   if (isImm(I.getOperand(4), MRI))
2277     return selectInsertVal(ResVReg, ResType, I);
2278   MachineBasicBlock &BB = *I.getParent();
2279   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorInsertDynamic))
2280       .addDef(ResVReg)
2281       .addUse(GR.getSPIRVTypeID(ResType))
2282       .addUse(I.getOperand(2).getReg())
2283       .addUse(I.getOperand(3).getReg())
2284       .addUse(I.getOperand(4).getReg())
2285       .constrainAllUses(TII, TRI, RBI);
2286 }
2287 
2288 bool SPIRVInstructionSelector::selectExtractElt(Register ResVReg,
2289                                                 const SPIRVType *ResType,
2290                                                 MachineInstr &I) const {
2291   if (isImm(I.getOperand(3), MRI))
2292     return selectExtractVal(ResVReg, ResType, I);
2293   MachineBasicBlock &BB = *I.getParent();
2294   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorExtractDynamic))
2295       .addDef(ResVReg)
2296       .addUse(GR.getSPIRVTypeID(ResType))
2297       .addUse(I.getOperand(2).getReg())
2298       .addUse(I.getOperand(3).getReg())
2299       .constrainAllUses(TII, TRI, RBI);
2300 }
2301 
2302 bool SPIRVInstructionSelector::selectGEP(Register ResVReg,
2303                                          const SPIRVType *ResType,
2304                                          MachineInstr &I) const {
2305   const bool IsGEPInBounds = I.getOperand(2).getImm();
2306 
2307   // OpAccessChain could be used for OpenCL, but the SPIRV-LLVM Translator only
2308   // relies on PtrAccessChain, so we'll try not to deviate. For Vulkan however,
2309   // we have to use Op[InBounds]AccessChain.
2310   const unsigned Opcode = STI.isVulkanEnv()
2311                               ? (IsGEPInBounds ? SPIRV::OpInBoundsAccessChain
2312                                                : SPIRV::OpAccessChain)
2313                               : (IsGEPInBounds ? SPIRV::OpInBoundsPtrAccessChain
2314                                                : SPIRV::OpPtrAccessChain);
2315 
2316   auto Res = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
2317                  .addDef(ResVReg)
2318                  .addUse(GR.getSPIRVTypeID(ResType))
2319                  // Object to get a pointer to.
2320                  .addUse(I.getOperand(3).getReg());
2321   // Adding indices.
2322   const unsigned StartingIndex =
2323       (Opcode == SPIRV::OpAccessChain || Opcode == SPIRV::OpInBoundsAccessChain)
2324           ? 5
2325           : 4;
2326   for (unsigned i = StartingIndex; i < I.getNumExplicitOperands(); ++i)
2327     Res.addUse(I.getOperand(i).getReg());
2328   return Res.constrainAllUses(TII, TRI, RBI);
2329 }
2330 
2331 // Maybe wrap a value into OpSpecConstantOp
2332 bool SPIRVInstructionSelector::wrapIntoSpecConstantOp(
2333     MachineInstr &I, SmallVector<Register> &CompositeArgs) const {
2334   bool Result = true;
2335   unsigned Lim = I.getNumExplicitOperands();
2336   for (unsigned i = I.getNumExplicitDefs() + 1; i < Lim; ++i) {
2337     Register OpReg = I.getOperand(i).getReg();
2338     SPIRVType *OpDefine = MRI->getVRegDef(OpReg);
2339     SPIRVType *OpType = GR.getSPIRVTypeForVReg(OpReg);
2340     SmallPtrSet<SPIRVType *, 4> Visited;
2341     if (!OpDefine || !OpType || isConstReg(MRI, OpDefine, Visited) ||
2342         OpDefine->getOpcode() == TargetOpcode::G_ADDRSPACE_CAST ||
2343         GR.isAggregateType(OpType)) {
2344       // The case of G_ADDRSPACE_CAST inside spv_const_composite() is processed
2345       // by selectAddrSpaceCast()
2346       CompositeArgs.push_back(OpReg);
2347       continue;
2348     }
2349     MachineFunction *MF = I.getMF();
2350     Register WrapReg = GR.find(OpDefine, MF);
2351     if (WrapReg.isValid()) {
2352       CompositeArgs.push_back(WrapReg);
2353       continue;
2354     }
2355     // Create a new register for the wrapper
2356     WrapReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2357     GR.add(OpDefine, MF, WrapReg);
2358     CompositeArgs.push_back(WrapReg);
2359     // Decorate the wrapper register and generate a new instruction
2360     MRI->setType(WrapReg, LLT::pointer(0, 64));
2361     GR.assignSPIRVTypeToVReg(OpType, WrapReg, *MF);
2362     MachineBasicBlock &BB = *I.getParent();
2363     Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
2364                  .addDef(WrapReg)
2365                  .addUse(GR.getSPIRVTypeID(OpType))
2366                  .addImm(static_cast<uint32_t>(SPIRV::Opcode::Bitcast))
2367                  .addUse(OpReg)
2368                  .constrainAllUses(TII, TRI, RBI);
2369     if (!Result)
2370       break;
2371   }
2372   return Result;
2373 }
2374 
2375 bool SPIRVInstructionSelector::selectIntrinsic(Register ResVReg,
2376                                                const SPIRVType *ResType,
2377                                                MachineInstr &I) const {
2378   MachineBasicBlock &BB = *I.getParent();
2379   Intrinsic::ID IID = cast<GIntrinsic>(I).getIntrinsicID();
2380   switch (IID) {
2381   case Intrinsic::spv_load:
2382     return selectLoad(ResVReg, ResType, I);
2383   case Intrinsic::spv_store:
2384     return selectStore(I);
2385   case Intrinsic::spv_extractv:
2386     return selectExtractVal(ResVReg, ResType, I);
2387   case Intrinsic::spv_insertv:
2388     return selectInsertVal(ResVReg, ResType, I);
2389   case Intrinsic::spv_extractelt:
2390     return selectExtractElt(ResVReg, ResType, I);
2391   case Intrinsic::spv_insertelt:
2392     return selectInsertElt(ResVReg, ResType, I);
2393   case Intrinsic::spv_gep:
2394     return selectGEP(ResVReg, ResType, I);
2395   case Intrinsic::spv_unref_global:
2396   case Intrinsic::spv_init_global: {
2397     MachineInstr *MI = MRI->getVRegDef(I.getOperand(1).getReg());
2398     MachineInstr *Init = I.getNumExplicitOperands() > 2
2399                              ? MRI->getVRegDef(I.getOperand(2).getReg())
2400                              : nullptr;
2401     assert(MI);
2402     return selectGlobalValue(MI->getOperand(0).getReg(), *MI, Init);
2403   }
2404   case Intrinsic::spv_undef: {
2405     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpUndef))
2406                    .addDef(ResVReg)
2407                    .addUse(GR.getSPIRVTypeID(ResType));
2408     return MIB.constrainAllUses(TII, TRI, RBI);
2409   }
2410   case Intrinsic::spv_const_composite: {
2411     // If no values are attached, the composite is null constant.
2412     bool IsNull = I.getNumExplicitDefs() + 1 == I.getNumExplicitOperands();
2413     // Select a proper instruction.
2414     unsigned Opcode = SPIRV::OpConstantNull;
2415     SmallVector<Register> CompositeArgs;
2416     if (!IsNull) {
2417       Opcode = SPIRV::OpConstantComposite;
2418       if (!wrapIntoSpecConstantOp(I, CompositeArgs))
2419         return false;
2420     }
2421     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2422                    .addDef(ResVReg)
2423                    .addUse(GR.getSPIRVTypeID(ResType));
2424     // skip type MD node we already used when generated assign.type for this
2425     if (!IsNull) {
2426       for (Register OpReg : CompositeArgs)
2427         MIB.addUse(OpReg);
2428     }
2429     return MIB.constrainAllUses(TII, TRI, RBI);
2430   }
2431   case Intrinsic::spv_assign_name: {
2432     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpName));
2433     MIB.addUse(I.getOperand(I.getNumExplicitDefs() + 1).getReg());
2434     for (unsigned i = I.getNumExplicitDefs() + 2;
2435          i < I.getNumExplicitOperands(); ++i) {
2436       MIB.addImm(I.getOperand(i).getImm());
2437     }
2438     return MIB.constrainAllUses(TII, TRI, RBI);
2439   }
2440   case Intrinsic::spv_switch: {
2441     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSwitch));
2442     for (unsigned i = 1; i < I.getNumExplicitOperands(); ++i) {
2443       if (I.getOperand(i).isReg())
2444         MIB.addReg(I.getOperand(i).getReg());
2445       else if (I.getOperand(i).isCImm())
2446         addNumImm(I.getOperand(i).getCImm()->getValue(), MIB);
2447       else if (I.getOperand(i).isMBB())
2448         MIB.addMBB(I.getOperand(i).getMBB());
2449       else
2450         llvm_unreachable("Unexpected OpSwitch operand");
2451     }
2452     return MIB.constrainAllUses(TII, TRI, RBI);
2453   }
2454   case Intrinsic::spv_loop_merge:
2455   case Intrinsic::spv_selection_merge: {
2456     const auto Opcode = IID == Intrinsic::spv_selection_merge
2457                             ? SPIRV::OpSelectionMerge
2458                             : SPIRV::OpLoopMerge;
2459     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode));
2460     for (unsigned i = 1; i < I.getNumExplicitOperands(); ++i) {
2461       assert(I.getOperand(i).isMBB());
2462       MIB.addMBB(I.getOperand(i).getMBB());
2463     }
2464     MIB.addImm(SPIRV::SelectionControl::None);
2465     return MIB.constrainAllUses(TII, TRI, RBI);
2466   }
2467   case Intrinsic::spv_cmpxchg:
2468     return selectAtomicCmpXchg(ResVReg, ResType, I);
2469   case Intrinsic::spv_unreachable:
2470     BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpUnreachable));
2471     break;
2472   case Intrinsic::spv_alloca:
2473     return selectFrameIndex(ResVReg, ResType, I);
2474   case Intrinsic::spv_alloca_array:
2475     return selectAllocaArray(ResVReg, ResType, I);
2476   case Intrinsic::spv_assume:
2477     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_expect_assume))
2478       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpAssumeTrueKHR))
2479           .addUse(I.getOperand(1).getReg());
2480     break;
2481   case Intrinsic::spv_expect:
2482     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_expect_assume))
2483       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExpectKHR))
2484           .addDef(ResVReg)
2485           .addUse(GR.getSPIRVTypeID(ResType))
2486           .addUse(I.getOperand(2).getReg())
2487           .addUse(I.getOperand(3).getReg());
2488     break;
2489   case Intrinsic::arithmetic_fence:
2490     if (STI.canUseExtension(SPIRV::Extension::SPV_EXT_arithmetic_fence))
2491       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpArithmeticFenceEXT))
2492           .addDef(ResVReg)
2493           .addUse(GR.getSPIRVTypeID(ResType))
2494           .addUse(I.getOperand(2).getReg());
2495     else
2496       BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY), ResVReg)
2497           .addUse(I.getOperand(2).getReg());
2498     break;
2499   case Intrinsic::spv_thread_id:
2500     return selectSpvThreadId(ResVReg, ResType, I);
2501   case Intrinsic::spv_fdot:
2502     return selectFloatDot(ResVReg, ResType, I);
2503   case Intrinsic::spv_udot:
2504   case Intrinsic::spv_sdot:
2505     return selectIntegerDot(ResVReg, ResType, I);
2506   case Intrinsic::spv_all:
2507     return selectAll(ResVReg, ResType, I);
2508   case Intrinsic::spv_any:
2509     return selectAny(ResVReg, ResType, I);
2510   case Intrinsic::spv_cross:
2511     return selectExtInst(ResVReg, ResType, I, CL::cross, GL::Cross);
2512   case Intrinsic::spv_lerp:
2513     return selectExtInst(ResVReg, ResType, I, CL::mix, GL::FMix);
2514   case Intrinsic::spv_length:
2515     return selectExtInst(ResVReg, ResType, I, CL::length, GL::Length);
2516   case Intrinsic::spv_degrees:
2517     return selectExtInst(ResVReg, ResType, I, CL::degrees, GL::Degrees);
2518   case Intrinsic::spv_frac:
2519     return selectExtInst(ResVReg, ResType, I, CL::fract, GL::Fract);
2520   case Intrinsic::spv_normalize:
2521     return selectExtInst(ResVReg, ResType, I, CL::normalize, GL::Normalize);
2522   case Intrinsic::spv_rsqrt:
2523     return selectExtInst(ResVReg, ResType, I, CL::rsqrt, GL::InverseSqrt);
2524   case Intrinsic::spv_sign:
2525     return selectSign(ResVReg, ResType, I);
2526   case Intrinsic::spv_lifetime_start:
2527   case Intrinsic::spv_lifetime_end: {
2528     unsigned Op = IID == Intrinsic::spv_lifetime_start ? SPIRV::OpLifetimeStart
2529                                                        : SPIRV::OpLifetimeStop;
2530     int64_t Size = I.getOperand(I.getNumExplicitDefs() + 1).getImm();
2531     Register PtrReg = I.getOperand(I.getNumExplicitDefs() + 2).getReg();
2532     if (Size == -1)
2533       Size = 0;
2534     BuildMI(BB, I, I.getDebugLoc(), TII.get(Op)).addUse(PtrReg).addImm(Size);
2535   } break;
2536   case Intrinsic::spv_saturate:
2537     return selectSaturate(ResVReg, ResType, I);
2538   case Intrinsic::spv_wave_is_first_lane: {
2539     SPIRVType *IntTy = GR.getOrCreateSPIRVIntegerType(32, I, TII);
2540     return BuildMI(BB, I, I.getDebugLoc(),
2541                    TII.get(SPIRV::OpGroupNonUniformElect))
2542         .addDef(ResVReg)
2543         .addUse(GR.getSPIRVTypeID(ResType))
2544         .addUse(GR.getOrCreateConstInt(3, I, IntTy, TII));
2545   }
2546   case Intrinsic::spv_step:
2547     return selectExtInst(ResVReg, ResType, I, CL::step, GL::Step);
2548   case Intrinsic::spv_radians:
2549     return selectExtInst(ResVReg, ResType, I, CL::radians, GL::Radians);
2550   // Discard intrinsics which we do not expect to actually represent code after
2551   // lowering or intrinsics which are not implemented but should not crash when
2552   // found in a customer's LLVM IR input.
2553   case Intrinsic::instrprof_increment:
2554   case Intrinsic::instrprof_increment_step:
2555   case Intrinsic::instrprof_value_profile:
2556     break;
2557   // Discard internal intrinsics.
2558   case Intrinsic::spv_value_md:
2559     break;
2560   case Intrinsic::spv_handle_fromBinding: {
2561     selectHandleFromBinding(ResVReg, ResType, I);
2562     return true;
2563   }
2564   default: {
2565     std::string DiagMsg;
2566     raw_string_ostream OS(DiagMsg);
2567     I.print(OS);
2568     DiagMsg = "Intrinsic selection not implemented: " + DiagMsg;
2569     report_fatal_error(DiagMsg.c_str(), false);
2570   }
2571   }
2572   return true;
2573 }
2574 
2575 void SPIRVInstructionSelector::selectHandleFromBinding(Register &ResVReg,
2576                                                        const SPIRVType *ResType,
2577                                                        MachineInstr &I) const {
2578 
2579   uint32_t Set = foldImm(I.getOperand(2), MRI);
2580   uint32_t Binding = foldImm(I.getOperand(3), MRI);
2581   uint32_t ArraySize = foldImm(I.getOperand(4), MRI);
2582 
2583   MachineIRBuilder MIRBuilder(I);
2584   Register VarReg =
2585       buildPointerToResource(ResType, Set, Binding, ArraySize, MIRBuilder);
2586 
2587   // TODO: For now we assume the resource is an image, which needs to be
2588   // loaded to get the handle. That will not be true for storage buffers.
2589   BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
2590       .addDef(ResVReg)
2591       .addUse(GR.getSPIRVTypeID(ResType))
2592       .addUse(VarReg);
2593 }
2594 
2595 Register SPIRVInstructionSelector::buildPointerToResource(
2596     const SPIRVType *ResType, uint32_t Set, uint32_t Binding,
2597     uint32_t ArraySize, MachineIRBuilder MIRBuilder) const {
2598   assert(ArraySize == 1 && "Resource arrays are not implemented yet.");
2599   return GR.getOrCreateGlobalVariableWithBinding(ResType, Set, Binding,
2600                                                  MIRBuilder);
2601 }
2602 
2603 bool SPIRVInstructionSelector::selectAllocaArray(Register ResVReg,
2604                                                  const SPIRVType *ResType,
2605                                                  MachineInstr &I) const {
2606   // there was an allocation size parameter to the allocation instruction
2607   // that is not 1
2608   MachineBasicBlock &BB = *I.getParent();
2609   return BuildMI(BB, I, I.getDebugLoc(),
2610                  TII.get(SPIRV::OpVariableLengthArrayINTEL))
2611       .addDef(ResVReg)
2612       .addUse(GR.getSPIRVTypeID(ResType))
2613       .addUse(I.getOperand(2).getReg())
2614       .constrainAllUses(TII, TRI, RBI);
2615 }
2616 
2617 bool SPIRVInstructionSelector::selectFrameIndex(Register ResVReg,
2618                                                 const SPIRVType *ResType,
2619                                                 MachineInstr &I) const {
2620   // Change order of instructions if needed: all OpVariable instructions in a
2621   // function must be the first instructions in the first block
2622   MachineFunction *MF = I.getParent()->getParent();
2623   MachineBasicBlock *MBB = &MF->front();
2624   auto It = MBB->SkipPHIsAndLabels(MBB->begin()), E = MBB->end();
2625   bool IsHeader = false;
2626   unsigned Opcode;
2627   for (; It != E && It != I; ++It) {
2628     Opcode = It->getOpcode();
2629     if (Opcode == SPIRV::OpFunction || Opcode == SPIRV::OpFunctionParameter) {
2630       IsHeader = true;
2631     } else if (IsHeader &&
2632                !(Opcode == SPIRV::ASSIGN_TYPE || Opcode == SPIRV::OpLabel)) {
2633       ++It;
2634       break;
2635     }
2636   }
2637   return BuildMI(*MBB, It, It->getDebugLoc(), TII.get(SPIRV::OpVariable))
2638       .addDef(ResVReg)
2639       .addUse(GR.getSPIRVTypeID(ResType))
2640       .addImm(static_cast<uint32_t>(SPIRV::StorageClass::Function))
2641       .constrainAllUses(TII, TRI, RBI);
2642 }
2643 
2644 bool SPIRVInstructionSelector::selectBranch(MachineInstr &I) const {
2645   // InstructionSelector walks backwards through the instructions. We can use
2646   // both a G_BR and a G_BRCOND to create an OpBranchConditional. We hit G_BR
2647   // first, so can generate an OpBranchConditional here. If there is no
2648   // G_BRCOND, we just use OpBranch for a regular unconditional branch.
2649   const MachineInstr *PrevI = I.getPrevNode();
2650   MachineBasicBlock &MBB = *I.getParent();
2651   if (PrevI != nullptr && PrevI->getOpcode() == TargetOpcode::G_BRCOND) {
2652     return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranchConditional))
2653         .addUse(PrevI->getOperand(0).getReg())
2654         .addMBB(PrevI->getOperand(1).getMBB())
2655         .addMBB(I.getOperand(0).getMBB())
2656         .constrainAllUses(TII, TRI, RBI);
2657   }
2658   return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranch))
2659       .addMBB(I.getOperand(0).getMBB())
2660       .constrainAllUses(TII, TRI, RBI);
2661 }
2662 
2663 bool SPIRVInstructionSelector::selectBranchCond(MachineInstr &I) const {
2664   // InstructionSelector walks backwards through the instructions. For an
2665   // explicit conditional branch with no fallthrough, we use both a G_BR and a
2666   // G_BRCOND to create an OpBranchConditional. We should hit G_BR first, and
2667   // generate the OpBranchConditional in selectBranch above.
2668   //
2669   // If an OpBranchConditional has been generated, we simply return, as the work
2670   // is alread done. If there is no OpBranchConditional, LLVM must be relying on
2671   // implicit fallthrough to the next basic block, so we need to create an
2672   // OpBranchConditional with an explicit "false" argument pointing to the next
2673   // basic block that LLVM would fall through to.
2674   const MachineInstr *NextI = I.getNextNode();
2675   // Check if this has already been successfully selected.
2676   if (NextI != nullptr && NextI->getOpcode() == SPIRV::OpBranchConditional)
2677     return true;
2678   // Must be relying on implicit block fallthrough, so generate an
2679   // OpBranchConditional with the "next" basic block as the "false" target.
2680   MachineBasicBlock &MBB = *I.getParent();
2681   unsigned NextMBBNum = MBB.getNextNode()->getNumber();
2682   MachineBasicBlock *NextMBB = I.getMF()->getBlockNumbered(NextMBBNum);
2683   return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranchConditional))
2684       .addUse(I.getOperand(0).getReg())
2685       .addMBB(I.getOperand(1).getMBB())
2686       .addMBB(NextMBB)
2687       .constrainAllUses(TII, TRI, RBI);
2688 }
2689 
2690 bool SPIRVInstructionSelector::selectPhi(Register ResVReg,
2691                                          const SPIRVType *ResType,
2692                                          MachineInstr &I) const {
2693   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpPhi))
2694                  .addDef(ResVReg)
2695                  .addUse(GR.getSPIRVTypeID(ResType));
2696   const unsigned NumOps = I.getNumOperands();
2697   for (unsigned i = 1; i < NumOps; i += 2) {
2698     MIB.addUse(I.getOperand(i + 0).getReg());
2699     MIB.addMBB(I.getOperand(i + 1).getMBB());
2700   }
2701   return MIB.constrainAllUses(TII, TRI, RBI);
2702 }
2703 
2704 bool SPIRVInstructionSelector::selectGlobalValue(
2705     Register ResVReg, MachineInstr &I, const MachineInstr *Init) const {
2706   // FIXME: don't use MachineIRBuilder here, replace it with BuildMI.
2707   MachineIRBuilder MIRBuilder(I);
2708   const GlobalValue *GV = I.getOperand(1).getGlobal();
2709   Type *GVType = toTypedPointer(GR.getDeducedGlobalValueType(GV));
2710   SPIRVType *PointerBaseType;
2711   if (GVType->isArrayTy()) {
2712     SPIRVType *ArrayElementType =
2713         GR.getOrCreateSPIRVType(GVType->getArrayElementType(), MIRBuilder,
2714                                 SPIRV::AccessQualifier::ReadWrite, false);
2715     PointerBaseType = GR.getOrCreateSPIRVArrayType(
2716         ArrayElementType, GVType->getArrayNumElements(), I, TII);
2717   } else {
2718     PointerBaseType = GR.getOrCreateSPIRVType(
2719         GVType, MIRBuilder, SPIRV::AccessQualifier::ReadWrite, false);
2720   }
2721   SPIRVType *ResType = GR.getOrCreateSPIRVPointerType(
2722       PointerBaseType, I, TII,
2723       addressSpaceToStorageClass(GV->getAddressSpace(), STI));
2724 
2725   std::string GlobalIdent;
2726   if (!GV->hasName()) {
2727     unsigned &ID = UnnamedGlobalIDs[GV];
2728     if (ID == 0)
2729       ID = UnnamedGlobalIDs.size();
2730     GlobalIdent = "__unnamed_" + Twine(ID).str();
2731   } else {
2732     GlobalIdent = GV->getGlobalIdentifier();
2733   }
2734 
2735   // Behaviour of functions as operands depends on availability of the
2736   // corresponding extension (SPV_INTEL_function_pointers):
2737   // - If there is an extension to operate with functions as operands:
2738   // We create a proper constant operand and evaluate a correct type for a
2739   // function pointer.
2740   // - Without the required extension:
2741   // We have functions as operands in tests with blocks of instruction e.g. in
2742   // transcoding/global_block.ll. These operands are not used and should be
2743   // substituted by zero constants. Their type is expected to be always
2744   // OpTypePointer Function %uchar.
2745   if (isa<Function>(GV)) {
2746     const Constant *ConstVal = GV;
2747     MachineBasicBlock &BB = *I.getParent();
2748     Register NewReg = GR.find(ConstVal, GR.CurMF);
2749     if (!NewReg.isValid()) {
2750       Register NewReg = ResVReg;
2751       GR.add(ConstVal, GR.CurMF, NewReg);
2752       const Function *GVFun =
2753           STI.canUseExtension(SPIRV::Extension::SPV_INTEL_function_pointers)
2754               ? dyn_cast<Function>(GV)
2755               : nullptr;
2756       if (GVFun) {
2757         // References to a function via function pointers generate virtual
2758         // registers without a definition. We will resolve it later, during
2759         // module analysis stage.
2760         MachineRegisterInfo *MRI = MIRBuilder.getMRI();
2761         Register FuncVReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
2762         MRI->setRegClass(FuncVReg, &SPIRV::iIDRegClass);
2763         MachineInstrBuilder MB =
2764             BuildMI(BB, I, I.getDebugLoc(),
2765                     TII.get(SPIRV::OpConstantFunctionPointerINTEL))
2766                 .addDef(NewReg)
2767                 .addUse(GR.getSPIRVTypeID(ResType))
2768                 .addUse(FuncVReg);
2769         // mapping the function pointer to the used Function
2770         GR.recordFunctionPointer(&MB.getInstr()->getOperand(2), GVFun);
2771         return MB.constrainAllUses(TII, TRI, RBI);
2772       }
2773       return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
2774           .addDef(NewReg)
2775           .addUse(GR.getSPIRVTypeID(ResType))
2776           .constrainAllUses(TII, TRI, RBI);
2777     }
2778     assert(NewReg != ResVReg);
2779     return BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY))
2780         .addDef(ResVReg)
2781         .addUse(NewReg)
2782         .constrainAllUses(TII, TRI, RBI);
2783   }
2784   auto GlobalVar = cast<GlobalVariable>(GV);
2785   assert(GlobalVar->getName() != "llvm.global.annotations");
2786 
2787   bool HasInit = GlobalVar->hasInitializer() &&
2788                  !isa<UndefValue>(GlobalVar->getInitializer());
2789   // Skip empty declaration for GVs with initilaizers till we get the decl with
2790   // passed initializer.
2791   if (HasInit && !Init)
2792     return true;
2793 
2794   unsigned AddrSpace = GV->getAddressSpace();
2795   SPIRV::StorageClass::StorageClass Storage =
2796       addressSpaceToStorageClass(AddrSpace, STI);
2797   bool HasLnkTy = GV->getLinkage() != GlobalValue::InternalLinkage &&
2798                   Storage != SPIRV::StorageClass::Function;
2799   SPIRV::LinkageType::LinkageType LnkType =
2800       (GV->isDeclaration() || GV->hasAvailableExternallyLinkage())
2801           ? SPIRV::LinkageType::Import
2802           : (GV->getLinkage() == GlobalValue::LinkOnceODRLinkage &&
2803                      STI.canUseExtension(SPIRV::Extension::SPV_KHR_linkonce_odr)
2804                  ? SPIRV::LinkageType::LinkOnceODR
2805                  : SPIRV::LinkageType::Export);
2806 
2807   Register Reg = GR.buildGlobalVariable(ResVReg, ResType, GlobalIdent, GV,
2808                                         Storage, Init, GlobalVar->isConstant(),
2809                                         HasLnkTy, LnkType, MIRBuilder, true);
2810   return Reg.isValid();
2811 }
2812 
2813 bool SPIRVInstructionSelector::selectLog10(Register ResVReg,
2814                                            const SPIRVType *ResType,
2815                                            MachineInstr &I) const {
2816   if (STI.canUseExtInstSet(SPIRV::InstructionSet::OpenCL_std)) {
2817     return selectExtInst(ResVReg, ResType, I, CL::log10);
2818   }
2819 
2820   // There is no log10 instruction in the GLSL Extended Instruction set, so it
2821   // is implemented as:
2822   // log10(x) = log2(x) * (1 / log2(10))
2823   //          = log2(x) * 0.30103
2824 
2825   MachineIRBuilder MIRBuilder(I);
2826   MachineBasicBlock &BB = *I.getParent();
2827 
2828   // Build log2(x).
2829   Register VarReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
2830   bool Result =
2831       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
2832           .addDef(VarReg)
2833           .addUse(GR.getSPIRVTypeID(ResType))
2834           .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
2835           .addImm(GL::Log2)
2836           .add(I.getOperand(1))
2837           .constrainAllUses(TII, TRI, RBI);
2838 
2839   // Build 0.30103.
2840   assert(ResType->getOpcode() == SPIRV::OpTypeVector ||
2841          ResType->getOpcode() == SPIRV::OpTypeFloat);
2842   // TODO: Add matrix implementation once supported by the HLSL frontend.
2843   const SPIRVType *SpirvScalarType =
2844       ResType->getOpcode() == SPIRV::OpTypeVector
2845           ? GR.getSPIRVTypeForVReg(ResType->getOperand(1).getReg())
2846           : ResType;
2847   Register ScaleReg =
2848       GR.buildConstantFP(APFloat(0.30103f), MIRBuilder, SpirvScalarType);
2849 
2850   // Multiply log2(x) by 0.30103 to get log10(x) result.
2851   auto Opcode = ResType->getOpcode() == SPIRV::OpTypeVector
2852                     ? SPIRV::OpVectorTimesScalar
2853                     : SPIRV::OpFMulS;
2854   Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2855                 .addDef(ResVReg)
2856                 .addUse(GR.getSPIRVTypeID(ResType))
2857                 .addUse(VarReg)
2858                 .addUse(ScaleReg)
2859                 .constrainAllUses(TII, TRI, RBI);
2860 
2861   return Result;
2862 }
2863 
2864 bool SPIRVInstructionSelector::selectSpvThreadId(Register ResVReg,
2865                                                  const SPIRVType *ResType,
2866                                                  MachineInstr &I) const {
2867   // DX intrinsic: @llvm.dx.thread.id(i32)
2868   // ID  Name      Description
2869   // 93  ThreadId  reads the thread ID
2870 
2871   MachineIRBuilder MIRBuilder(I);
2872   const SPIRVType *U32Type = GR.getOrCreateSPIRVIntegerType(32, MIRBuilder);
2873   const SPIRVType *Vec3Ty =
2874       GR.getOrCreateSPIRVVectorType(U32Type, 3, MIRBuilder);
2875   const SPIRVType *PtrType = GR.getOrCreateSPIRVPointerType(
2876       Vec3Ty, MIRBuilder, SPIRV::StorageClass::Input);
2877 
2878   // Create new register for GlobalInvocationID builtin variable.
2879   Register NewRegister =
2880       MIRBuilder.getMRI()->createVirtualRegister(&SPIRV::iIDRegClass);
2881   MIRBuilder.getMRI()->setType(NewRegister, LLT::pointer(0, 64));
2882   GR.assignSPIRVTypeToVReg(PtrType, NewRegister, MIRBuilder.getMF());
2883 
2884   // Build GlobalInvocationID global variable with the necessary decorations.
2885   Register Variable = GR.buildGlobalVariable(
2886       NewRegister, PtrType,
2887       getLinkStringForBuiltIn(SPIRV::BuiltIn::GlobalInvocationId), nullptr,
2888       SPIRV::StorageClass::Input, nullptr, true, true,
2889       SPIRV::LinkageType::Import, MIRBuilder, false);
2890 
2891   // Create new register for loading value.
2892   MachineRegisterInfo *MRI = MIRBuilder.getMRI();
2893   Register LoadedRegister = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2894   MIRBuilder.getMRI()->setType(LoadedRegister, LLT::pointer(0, 64));
2895   GR.assignSPIRVTypeToVReg(Vec3Ty, LoadedRegister, MIRBuilder.getMF());
2896 
2897   // Load v3uint value from the global variable.
2898   BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
2899       .addDef(LoadedRegister)
2900       .addUse(GR.getSPIRVTypeID(Vec3Ty))
2901       .addUse(Variable);
2902 
2903   // Get Thread ID index. Expecting operand is a constant immediate value,
2904   // wrapped in a type assignment.
2905   assert(I.getOperand(2).isReg());
2906   const uint32_t ThreadId = foldImm(I.getOperand(2), MRI);
2907 
2908   // Extract the thread ID from the loaded vector value.
2909   MachineBasicBlock &BB = *I.getParent();
2910   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
2911                  .addDef(ResVReg)
2912                  .addUse(GR.getSPIRVTypeID(ResType))
2913                  .addUse(LoadedRegister)
2914                  .addImm(ThreadId);
2915   return MIB.constrainAllUses(TII, TRI, RBI);
2916 }
2917 
2918 namespace llvm {
2919 InstructionSelector *
2920 createSPIRVInstructionSelector(const SPIRVTargetMachine &TM,
2921                                const SPIRVSubtarget &Subtarget,
2922                                const RegisterBankInfo &RBI) {
2923   return new SPIRVInstructionSelector(TM, Subtarget, RBI);
2924 }
2925 } // namespace llvm
2926