xref: /llvm-project/llvm/lib/Target/SPIRV/SPIRVInstructionSelector.cpp (revision 3cdac0670823e2da58001bc2600d2e74c929ae5b)
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   template <bool Signed>
168   bool selectDot4AddPacked(Register ResVReg, const SPIRVType *ResType,
169                            MachineInstr &I) const;
170   template <bool Signed>
171   bool selectDot4AddPackedExpansion(Register ResVReg, const SPIRVType *ResType,
172                                     MachineInstr &I) const;
173 
174   void renderImm32(MachineInstrBuilder &MIB, const MachineInstr &I,
175                    int OpIdx) const;
176   void renderFImm64(MachineInstrBuilder &MIB, const MachineInstr &I,
177                     int OpIdx) const;
178 
179   bool selectConst(Register ResVReg, const SPIRVType *ResType, const APInt &Imm,
180                    MachineInstr &I) const;
181 
182   bool selectSelect(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
183                     bool IsSigned) const;
184   bool selectIToF(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
185                   bool IsSigned, unsigned Opcode) const;
186   bool selectExt(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
187                  bool IsSigned) const;
188 
189   bool selectTrunc(Register ResVReg, const SPIRVType *ResType,
190                    MachineInstr &I) const;
191 
192   bool selectIntToBool(Register IntReg, Register ResVReg, MachineInstr &I,
193                        const SPIRVType *intTy, const SPIRVType *boolTy) const;
194 
195   bool selectOpUndef(Register ResVReg, const SPIRVType *ResType,
196                      MachineInstr &I) const;
197   bool selectFreeze(Register ResVReg, const SPIRVType *ResType,
198                     MachineInstr &I) const;
199   bool selectIntrinsic(Register ResVReg, const SPIRVType *ResType,
200                        MachineInstr &I) const;
201   bool selectExtractVal(Register ResVReg, const SPIRVType *ResType,
202                         MachineInstr &I) const;
203   bool selectInsertVal(Register ResVReg, const SPIRVType *ResType,
204                        MachineInstr &I) const;
205   bool selectExtractElt(Register ResVReg, const SPIRVType *ResType,
206                         MachineInstr &I) const;
207   bool selectInsertElt(Register ResVReg, const SPIRVType *ResType,
208                        MachineInstr &I) const;
209   bool selectGEP(Register ResVReg, const SPIRVType *ResType,
210                  MachineInstr &I) const;
211 
212   bool selectFrameIndex(Register ResVReg, const SPIRVType *ResType,
213                         MachineInstr &I) const;
214   bool selectAllocaArray(Register ResVReg, const SPIRVType *ResType,
215                          MachineInstr &I) const;
216 
217   bool selectBranch(MachineInstr &I) const;
218   bool selectBranchCond(MachineInstr &I) const;
219 
220   bool selectPhi(Register ResVReg, const SPIRVType *ResType,
221                  MachineInstr &I) const;
222 
223   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
224                      MachineInstr &I, CL::OpenCLExtInst CLInst) const;
225   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
226                      MachineInstr &I, CL::OpenCLExtInst CLInst,
227                      GL::GLSLExtInst GLInst) const;
228   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
229                      MachineInstr &I, const ExtInstList &ExtInsts) const;
230 
231   bool selectLog10(Register ResVReg, const SPIRVType *ResType,
232                    MachineInstr &I) const;
233 
234   bool selectSaturate(Register ResVReg, const SPIRVType *ResType,
235                       MachineInstr &I) const;
236 
237   bool selectSpvThreadId(Register ResVReg, const SPIRVType *ResType,
238                          MachineInstr &I) const;
239 
240   bool selectWaveReadLaneAt(Register ResVReg, const SPIRVType *ResType,
241                             MachineInstr &I) const;
242 
243   bool selectUnmergeValues(MachineInstr &I) const;
244 
245   void selectHandleFromBinding(Register &ResVReg, const SPIRVType *ResType,
246                                MachineInstr &I) const;
247 
248   // Utilities
249   Register buildI32Constant(uint32_t Val, MachineInstr &I,
250                             const SPIRVType *ResType = nullptr) const;
251 
252   Register buildZerosVal(const SPIRVType *ResType, MachineInstr &I) const;
253   Register buildZerosValF(const SPIRVType *ResType, MachineInstr &I) const;
254   Register buildOnesVal(bool AllOnes, const SPIRVType *ResType,
255                         MachineInstr &I) const;
256   Register buildOnesValF(const SPIRVType *ResType, MachineInstr &I) const;
257 
258   bool wrapIntoSpecConstantOp(MachineInstr &I,
259                               SmallVector<Register> &CompositeArgs) const;
260 
261   Register getUcharPtrTypeReg(MachineInstr &I,
262                               SPIRV::StorageClass::StorageClass SC) const;
263   MachineInstrBuilder buildSpecConstantOp(MachineInstr &I, Register Dest,
264                                           Register Src, Register DestType,
265                                           uint32_t Opcode) const;
266   MachineInstrBuilder buildConstGenericPtr(MachineInstr &I, Register SrcPtr,
267                                            SPIRVType *SrcPtrTy) const;
268   Register buildPointerToResource(const SPIRVType *ResType, uint32_t Set,
269                                   uint32_t Binding, uint32_t ArraySize,
270                                   Register IndexReg, bool IsNonUniform,
271                                   MachineIRBuilder MIRBuilder) const;
272 };
273 
274 } // end anonymous namespace
275 
276 #define GET_GLOBALISEL_IMPL
277 #include "SPIRVGenGlobalISel.inc"
278 #undef GET_GLOBALISEL_IMPL
279 
280 SPIRVInstructionSelector::SPIRVInstructionSelector(const SPIRVTargetMachine &TM,
281                                                    const SPIRVSubtarget &ST,
282                                                    const RegisterBankInfo &RBI)
283     : InstructionSelector(), STI(ST), TII(*ST.getInstrInfo()),
284       TRI(*ST.getRegisterInfo()), RBI(RBI), GR(*ST.getSPIRVGlobalRegistry()),
285 #define GET_GLOBALISEL_PREDICATES_INIT
286 #include "SPIRVGenGlobalISel.inc"
287 #undef GET_GLOBALISEL_PREDICATES_INIT
288 #define GET_GLOBALISEL_TEMPORARIES_INIT
289 #include "SPIRVGenGlobalISel.inc"
290 #undef GET_GLOBALISEL_TEMPORARIES_INIT
291 {
292 }
293 
294 void SPIRVInstructionSelector::setupMF(MachineFunction &MF, GISelKnownBits *KB,
295                                        CodeGenCoverage *CoverageInfo,
296                                        ProfileSummaryInfo *PSI,
297                                        BlockFrequencyInfo *BFI) {
298   MRI = &MF.getRegInfo();
299   GR.setCurrentFunc(MF);
300   InstructionSelector::setupMF(MF, KB, CoverageInfo, PSI, BFI);
301 }
302 
303 // Ensure that register classes correspond to pattern matching rules.
304 void SPIRVInstructionSelector::resetVRegsType(MachineFunction &MF) {
305   if (HasVRegsReset == &MF)
306     return;
307   HasVRegsReset = &MF;
308 
309   MachineRegisterInfo &MRI = MF.getRegInfo();
310   for (unsigned I = 0, E = MRI.getNumVirtRegs(); I != E; ++I) {
311     Register Reg = Register::index2VirtReg(I);
312     LLT RegType = MRI.getType(Reg);
313     if (RegType.isScalar())
314       MRI.setType(Reg, LLT::scalar(64));
315     else if (RegType.isPointer())
316       MRI.setType(Reg, LLT::pointer(0, 64));
317     else if (RegType.isVector())
318       MRI.setType(Reg, LLT::fixed_vector(2, LLT::scalar(64)));
319   }
320   for (const auto &MBB : MF) {
321     for (const auto &MI : MBB) {
322       if (MI.getOpcode() != SPIRV::ASSIGN_TYPE)
323         continue;
324       Register DstReg = MI.getOperand(0).getReg();
325       LLT DstType = MRI.getType(DstReg);
326       Register SrcReg = MI.getOperand(1).getReg();
327       LLT SrcType = MRI.getType(SrcReg);
328       if (DstType != SrcType)
329         MRI.setType(DstReg, MRI.getType(SrcReg));
330 
331       const TargetRegisterClass *DstRC = MRI.getRegClassOrNull(DstReg);
332       const TargetRegisterClass *SrcRC = MRI.getRegClassOrNull(SrcReg);
333       if (DstRC != SrcRC && SrcRC)
334         MRI.setRegClass(DstReg, SrcRC);
335     }
336   }
337 }
338 
339 static bool isImm(const MachineOperand &MO, MachineRegisterInfo *MRI);
340 
341 // Defined in SPIRVLegalizerInfo.cpp.
342 extern bool isTypeFoldingSupported(unsigned Opcode);
343 
344 bool SPIRVInstructionSelector::select(MachineInstr &I) {
345   resetVRegsType(*I.getParent()->getParent());
346 
347   assert(I.getParent() && "Instruction should be in a basic block!");
348   assert(I.getParent()->getParent() && "Instruction should be in a function!");
349 
350   Register Opcode = I.getOpcode();
351   // If it's not a GMIR instruction, we've selected it already.
352   if (!isPreISelGenericOpcode(Opcode)) {
353     if (Opcode == SPIRV::ASSIGN_TYPE) { // These pseudos aren't needed any more.
354       Register DstReg = I.getOperand(0).getReg();
355       Register SrcReg = I.getOperand(1).getReg();
356       auto *Def = MRI->getVRegDef(SrcReg);
357       if (isTypeFoldingSupported(Def->getOpcode())) {
358         bool Res = selectImpl(I, *CoverageInfo);
359         LLVM_DEBUG({
360           if (!Res && Def->getOpcode() != TargetOpcode::G_CONSTANT) {
361             dbgs() << "Unexpected pattern in ASSIGN_TYPE.\nInstruction: ";
362             I.print(dbgs());
363           }
364         });
365         assert(Res || Def->getOpcode() == TargetOpcode::G_CONSTANT);
366         if (Res)
367           return Res;
368       }
369       MRI->setRegClass(SrcReg, MRI->getRegClass(DstReg));
370       MRI->replaceRegWith(SrcReg, DstReg);
371       I.removeFromParent();
372       return true;
373     } else if (I.getNumDefs() == 1) {
374       // Make all vregs 64 bits (for SPIR-V IDs).
375       MRI->setType(I.getOperand(0).getReg(), LLT::scalar(64));
376     }
377     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
378   }
379 
380   if (I.getNumOperands() != I.getNumExplicitOperands()) {
381     LLVM_DEBUG(errs() << "Generic instr has unexpected implicit operands\n");
382     return false;
383   }
384 
385   // Common code for getting return reg+type, and removing selected instr
386   // from parent occurs here. Instr-specific selection happens in spvSelect().
387   bool HasDefs = I.getNumDefs() > 0;
388   Register ResVReg = HasDefs ? I.getOperand(0).getReg() : Register(0);
389   SPIRVType *ResType = HasDefs ? GR.getSPIRVTypeForVReg(ResVReg) : nullptr;
390   assert(!HasDefs || ResType || I.getOpcode() == TargetOpcode::G_GLOBAL_VALUE);
391   if (spvSelect(ResVReg, ResType, I)) {
392     if (HasDefs) // Make all vregs 64 bits (for SPIR-V IDs).
393       for (unsigned i = 0; i < I.getNumDefs(); ++i)
394         MRI->setType(I.getOperand(i).getReg(), LLT::scalar(64));
395     I.removeFromParent();
396     return true;
397   }
398   return false;
399 }
400 
401 static bool mayApplyGenericSelection(unsigned Opcode) {
402   switch (Opcode) {
403   case TargetOpcode::G_CONSTANT:
404     return false;
405   case TargetOpcode::G_SADDO:
406   case TargetOpcode::G_SSUBO:
407     return true;
408   }
409   return isTypeFoldingSupported(Opcode);
410 }
411 
412 bool SPIRVInstructionSelector::spvSelect(Register ResVReg,
413                                          const SPIRVType *ResType,
414                                          MachineInstr &I) const {
415   const unsigned Opcode = I.getOpcode();
416   if (mayApplyGenericSelection(Opcode))
417     return selectImpl(I, *CoverageInfo);
418   switch (Opcode) {
419   case TargetOpcode::G_CONSTANT:
420     return selectConst(ResVReg, ResType, I.getOperand(1).getCImm()->getValue(),
421                        I);
422   case TargetOpcode::G_GLOBAL_VALUE:
423     return selectGlobalValue(ResVReg, I);
424   case TargetOpcode::G_IMPLICIT_DEF:
425     return selectOpUndef(ResVReg, ResType, I);
426   case TargetOpcode::G_FREEZE:
427     return selectFreeze(ResVReg, ResType, I);
428 
429   case TargetOpcode::G_INTRINSIC:
430   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
431   case TargetOpcode::G_INTRINSIC_CONVERGENT:
432   case TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS:
433     return selectIntrinsic(ResVReg, ResType, I);
434   case TargetOpcode::G_BITREVERSE:
435     return selectBitreverse(ResVReg, ResType, I);
436 
437   case TargetOpcode::G_BUILD_VECTOR:
438     return selectBuildVector(ResVReg, ResType, I);
439   case TargetOpcode::G_SPLAT_VECTOR:
440     return selectSplatVector(ResVReg, ResType, I);
441 
442   case TargetOpcode::G_SHUFFLE_VECTOR: {
443     MachineBasicBlock &BB = *I.getParent();
444     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorShuffle))
445                    .addDef(ResVReg)
446                    .addUse(GR.getSPIRVTypeID(ResType))
447                    .addUse(I.getOperand(1).getReg())
448                    .addUse(I.getOperand(2).getReg());
449     for (auto V : I.getOperand(3).getShuffleMask())
450       MIB.addImm(V);
451     return MIB.constrainAllUses(TII, TRI, RBI);
452   }
453   case TargetOpcode::G_MEMMOVE:
454   case TargetOpcode::G_MEMCPY:
455   case TargetOpcode::G_MEMSET:
456     return selectMemOperation(ResVReg, I);
457 
458   case TargetOpcode::G_ICMP:
459     return selectICmp(ResVReg, ResType, I);
460   case TargetOpcode::G_FCMP:
461     return selectFCmp(ResVReg, ResType, I);
462 
463   case TargetOpcode::G_FRAME_INDEX:
464     return selectFrameIndex(ResVReg, ResType, I);
465 
466   case TargetOpcode::G_LOAD:
467     return selectLoad(ResVReg, ResType, I);
468   case TargetOpcode::G_STORE:
469     return selectStore(I);
470 
471   case TargetOpcode::G_BR:
472     return selectBranch(I);
473   case TargetOpcode::G_BRCOND:
474     return selectBranchCond(I);
475 
476   case TargetOpcode::G_PHI:
477     return selectPhi(ResVReg, ResType, I);
478 
479   case TargetOpcode::G_FPTOSI:
480     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertFToS);
481   case TargetOpcode::G_FPTOUI:
482     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertFToU);
483 
484   case TargetOpcode::G_SITOFP:
485     return selectIToF(ResVReg, ResType, I, true, SPIRV::OpConvertSToF);
486   case TargetOpcode::G_UITOFP:
487     return selectIToF(ResVReg, ResType, I, false, SPIRV::OpConvertUToF);
488 
489   case TargetOpcode::G_CTPOP:
490     return selectUnOp(ResVReg, ResType, I, SPIRV::OpBitCount);
491   case TargetOpcode::G_SMIN:
492     return selectExtInst(ResVReg, ResType, I, CL::s_min, GL::SMin);
493   case TargetOpcode::G_UMIN:
494     return selectExtInst(ResVReg, ResType, I, CL::u_min, GL::UMin);
495 
496   case TargetOpcode::G_SMAX:
497     return selectExtInst(ResVReg, ResType, I, CL::s_max, GL::SMax);
498   case TargetOpcode::G_UMAX:
499     return selectExtInst(ResVReg, ResType, I, CL::u_max, GL::UMax);
500 
501   case TargetOpcode::G_FMA:
502     return selectExtInst(ResVReg, ResType, I, CL::fma, GL::Fma);
503 
504   case TargetOpcode::G_FPOW:
505     return selectExtInst(ResVReg, ResType, I, CL::pow, GL::Pow);
506   case TargetOpcode::G_FPOWI:
507     return selectExtInst(ResVReg, ResType, I, CL::pown);
508 
509   case TargetOpcode::G_FEXP:
510     return selectExtInst(ResVReg, ResType, I, CL::exp, GL::Exp);
511   case TargetOpcode::G_FEXP2:
512     return selectExtInst(ResVReg, ResType, I, CL::exp2, GL::Exp2);
513 
514   case TargetOpcode::G_FLOG:
515     return selectExtInst(ResVReg, ResType, I, CL::log, GL::Log);
516   case TargetOpcode::G_FLOG2:
517     return selectExtInst(ResVReg, ResType, I, CL::log2, GL::Log2);
518   case TargetOpcode::G_FLOG10:
519     return selectLog10(ResVReg, ResType, I);
520 
521   case TargetOpcode::G_FABS:
522     return selectExtInst(ResVReg, ResType, I, CL::fabs, GL::FAbs);
523   case TargetOpcode::G_ABS:
524     return selectExtInst(ResVReg, ResType, I, CL::s_abs, GL::SAbs);
525 
526   case TargetOpcode::G_FMINNUM:
527   case TargetOpcode::G_FMINIMUM:
528     return selectExtInst(ResVReg, ResType, I, CL::fmin, GL::NMin);
529   case TargetOpcode::G_FMAXNUM:
530   case TargetOpcode::G_FMAXIMUM:
531     return selectExtInst(ResVReg, ResType, I, CL::fmax, GL::NMax);
532 
533   case TargetOpcode::G_FCOPYSIGN:
534     return selectExtInst(ResVReg, ResType, I, CL::copysign);
535 
536   case TargetOpcode::G_FCEIL:
537     return selectExtInst(ResVReg, ResType, I, CL::ceil, GL::Ceil);
538   case TargetOpcode::G_FFLOOR:
539     return selectExtInst(ResVReg, ResType, I, CL::floor, GL::Floor);
540 
541   case TargetOpcode::G_FCOS:
542     return selectExtInst(ResVReg, ResType, I, CL::cos, GL::Cos);
543   case TargetOpcode::G_FSIN:
544     return selectExtInst(ResVReg, ResType, I, CL::sin, GL::Sin);
545   case TargetOpcode::G_FTAN:
546     return selectExtInst(ResVReg, ResType, I, CL::tan, GL::Tan);
547   case TargetOpcode::G_FACOS:
548     return selectExtInst(ResVReg, ResType, I, CL::acos, GL::Acos);
549   case TargetOpcode::G_FASIN:
550     return selectExtInst(ResVReg, ResType, I, CL::asin, GL::Asin);
551   case TargetOpcode::G_FATAN:
552     return selectExtInst(ResVReg, ResType, I, CL::atan, GL::Atan);
553   case TargetOpcode::G_FATAN2:
554     return selectExtInst(ResVReg, ResType, I, CL::atan2, GL::Atan2);
555   case TargetOpcode::G_FCOSH:
556     return selectExtInst(ResVReg, ResType, I, CL::cosh, GL::Cosh);
557   case TargetOpcode::G_FSINH:
558     return selectExtInst(ResVReg, ResType, I, CL::sinh, GL::Sinh);
559   case TargetOpcode::G_FTANH:
560     return selectExtInst(ResVReg, ResType, I, CL::tanh, GL::Tanh);
561 
562   case TargetOpcode::G_FSQRT:
563     return selectExtInst(ResVReg, ResType, I, CL::sqrt, GL::Sqrt);
564 
565   case TargetOpcode::G_CTTZ:
566   case TargetOpcode::G_CTTZ_ZERO_UNDEF:
567     return selectExtInst(ResVReg, ResType, I, CL::ctz);
568   case TargetOpcode::G_CTLZ:
569   case TargetOpcode::G_CTLZ_ZERO_UNDEF:
570     return selectExtInst(ResVReg, ResType, I, CL::clz);
571 
572   case TargetOpcode::G_INTRINSIC_ROUND:
573     return selectExtInst(ResVReg, ResType, I, CL::round, GL::Round);
574   case TargetOpcode::G_INTRINSIC_ROUNDEVEN:
575     return selectExtInst(ResVReg, ResType, I, CL::rint, GL::RoundEven);
576   case TargetOpcode::G_INTRINSIC_TRUNC:
577     return selectExtInst(ResVReg, ResType, I, CL::trunc, GL::Trunc);
578   case TargetOpcode::G_FRINT:
579   case TargetOpcode::G_FNEARBYINT:
580     return selectExtInst(ResVReg, ResType, I, CL::rint, GL::RoundEven);
581 
582   case TargetOpcode::G_SMULH:
583     return selectExtInst(ResVReg, ResType, I, CL::s_mul_hi);
584   case TargetOpcode::G_UMULH:
585     return selectExtInst(ResVReg, ResType, I, CL::u_mul_hi);
586 
587   case TargetOpcode::G_SADDSAT:
588     return selectExtInst(ResVReg, ResType, I, CL::s_add_sat);
589   case TargetOpcode::G_UADDSAT:
590     return selectExtInst(ResVReg, ResType, I, CL::u_add_sat);
591   case TargetOpcode::G_SSUBSAT:
592     return selectExtInst(ResVReg, ResType, I, CL::s_sub_sat);
593   case TargetOpcode::G_USUBSAT:
594     return selectExtInst(ResVReg, ResType, I, CL::u_sub_sat);
595 
596   case TargetOpcode::G_UADDO:
597     return selectOverflowArith(ResVReg, ResType, I,
598                                ResType->getOpcode() == SPIRV::OpTypeVector
599                                    ? SPIRV::OpIAddCarryV
600                                    : SPIRV::OpIAddCarryS);
601   case TargetOpcode::G_USUBO:
602     return selectOverflowArith(ResVReg, ResType, I,
603                                ResType->getOpcode() == SPIRV::OpTypeVector
604                                    ? SPIRV::OpISubBorrowV
605                                    : SPIRV::OpISubBorrowS);
606   case TargetOpcode::G_UMULO:
607     return selectOverflowArith(ResVReg, ResType, I, SPIRV::OpUMulExtended);
608   case TargetOpcode::G_SMULO:
609     return selectOverflowArith(ResVReg, ResType, I, SPIRV::OpSMulExtended);
610 
611   case TargetOpcode::G_SEXT:
612     return selectExt(ResVReg, ResType, I, true);
613   case TargetOpcode::G_ANYEXT:
614   case TargetOpcode::G_ZEXT:
615     return selectExt(ResVReg, ResType, I, false);
616   case TargetOpcode::G_TRUNC:
617     return selectTrunc(ResVReg, ResType, I);
618   case TargetOpcode::G_FPTRUNC:
619   case TargetOpcode::G_FPEXT:
620     return selectUnOp(ResVReg, ResType, I, SPIRV::OpFConvert);
621 
622   case TargetOpcode::G_PTRTOINT:
623     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertPtrToU);
624   case TargetOpcode::G_INTTOPTR:
625     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertUToPtr);
626   case TargetOpcode::G_BITCAST:
627     return selectBitcast(ResVReg, ResType, I);
628   case TargetOpcode::G_ADDRSPACE_CAST:
629     return selectAddrSpaceCast(ResVReg, ResType, I);
630   case TargetOpcode::G_PTR_ADD: {
631     // Currently, we get G_PTR_ADD only applied to global variables.
632     assert(I.getOperand(1).isReg() && I.getOperand(2).isReg());
633     Register GV = I.getOperand(1).getReg();
634     MachineRegisterInfo::def_instr_iterator II = MRI->def_instr_begin(GV);
635     (void)II;
636     assert(((*II).getOpcode() == TargetOpcode::G_GLOBAL_VALUE ||
637             (*II).getOpcode() == TargetOpcode::COPY ||
638             (*II).getOpcode() == SPIRV::OpVariable) &&
639            isImm(I.getOperand(2), MRI));
640     // It may be the initialization of a global variable.
641     bool IsGVInit = false;
642     for (MachineRegisterInfo::use_instr_iterator
643              UseIt = MRI->use_instr_begin(I.getOperand(0).getReg()),
644              UseEnd = MRI->use_instr_end();
645          UseIt != UseEnd; UseIt = std::next(UseIt)) {
646       if ((*UseIt).getOpcode() == TargetOpcode::G_GLOBAL_VALUE ||
647           (*UseIt).getOpcode() == SPIRV::OpVariable) {
648         IsGVInit = true;
649         break;
650       }
651     }
652     MachineBasicBlock &BB = *I.getParent();
653     if (!IsGVInit) {
654       SPIRVType *GVType = GR.getSPIRVTypeForVReg(GV);
655       SPIRVType *GVPointeeType = GR.getPointeeType(GVType);
656       SPIRVType *ResPointeeType = GR.getPointeeType(ResType);
657       if (GVPointeeType && ResPointeeType && GVPointeeType != ResPointeeType) {
658         // Build a new virtual register that is associated with the required
659         // data type.
660         Register NewVReg = MRI->createGenericVirtualRegister(MRI->getType(GV));
661         MRI->setRegClass(NewVReg, MRI->getRegClass(GV));
662         //  Having a correctly typed base we are ready to build the actually
663         //  required GEP. It may not be a constant though, because all Operands
664         //  of OpSpecConstantOp is to originate from other const instructions,
665         //  and only the AccessChain named opcodes accept a global OpVariable
666         //  instruction. We can't use an AccessChain opcode because of the type
667         //  mismatch between result and base types.
668         if (!GR.isBitcastCompatible(ResType, GVType))
669           report_fatal_error(
670               "incompatible result and operand types in a bitcast");
671         Register ResTypeReg = GR.getSPIRVTypeID(ResType);
672         MachineInstrBuilder MIB =
673             BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpBitcast))
674                 .addDef(NewVReg)
675                 .addUse(ResTypeReg)
676                 .addUse(GV);
677         return MIB.constrainAllUses(TII, TRI, RBI) &&
678                BuildMI(BB, I, I.getDebugLoc(),
679                        TII.get(STI.isVulkanEnv()
680                                    ? SPIRV::OpInBoundsAccessChain
681                                    : SPIRV::OpInBoundsPtrAccessChain))
682                    .addDef(ResVReg)
683                    .addUse(ResTypeReg)
684                    .addUse(NewVReg)
685                    .addUse(I.getOperand(2).getReg())
686                    .constrainAllUses(TII, TRI, RBI);
687       } else {
688         return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
689             .addDef(ResVReg)
690             .addUse(GR.getSPIRVTypeID(ResType))
691             .addImm(
692                 static_cast<uint32_t>(SPIRV::Opcode::InBoundsPtrAccessChain))
693             .addUse(GV)
694             .addUse(I.getOperand(2).getReg())
695             .constrainAllUses(TII, TRI, RBI);
696       }
697     }
698     // It's possible to translate G_PTR_ADD to OpSpecConstantOp: either to
699     // initialize a global variable with a constant expression (e.g., the test
700     // case opencl/basic/progvar_prog_scope_init.ll), or for another use case
701     Register Idx = buildZerosVal(GR.getOrCreateSPIRVIntegerType(32, I, TII), I);
702     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
703                    .addDef(ResVReg)
704                    .addUse(GR.getSPIRVTypeID(ResType))
705                    .addImm(static_cast<uint32_t>(
706                        SPIRV::Opcode::InBoundsPtrAccessChain))
707                    .addUse(GV)
708                    .addUse(Idx)
709                    .addUse(I.getOperand(2).getReg());
710     return MIB.constrainAllUses(TII, TRI, RBI);
711   }
712 
713   case TargetOpcode::G_ATOMICRMW_OR:
714     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicOr);
715   case TargetOpcode::G_ATOMICRMW_ADD:
716     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicIAdd);
717   case TargetOpcode::G_ATOMICRMW_AND:
718     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicAnd);
719   case TargetOpcode::G_ATOMICRMW_MAX:
720     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicSMax);
721   case TargetOpcode::G_ATOMICRMW_MIN:
722     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicSMin);
723   case TargetOpcode::G_ATOMICRMW_SUB:
724     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicISub);
725   case TargetOpcode::G_ATOMICRMW_XOR:
726     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicXor);
727   case TargetOpcode::G_ATOMICRMW_UMAX:
728     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicUMax);
729   case TargetOpcode::G_ATOMICRMW_UMIN:
730     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicUMin);
731   case TargetOpcode::G_ATOMICRMW_XCHG:
732     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicExchange);
733   case TargetOpcode::G_ATOMIC_CMPXCHG:
734     return selectAtomicCmpXchg(ResVReg, ResType, I);
735 
736   case TargetOpcode::G_ATOMICRMW_FADD:
737     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFAddEXT);
738   case TargetOpcode::G_ATOMICRMW_FSUB:
739     // Translate G_ATOMICRMW_FSUB to OpAtomicFAddEXT with negative value operand
740     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFAddEXT,
741                            SPIRV::OpFNegate);
742   case TargetOpcode::G_ATOMICRMW_FMIN:
743     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFMinEXT);
744   case TargetOpcode::G_ATOMICRMW_FMAX:
745     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFMaxEXT);
746 
747   case TargetOpcode::G_FENCE:
748     return selectFence(I);
749 
750   case TargetOpcode::G_STACKSAVE:
751     return selectStackSave(ResVReg, ResType, I);
752   case TargetOpcode::G_STACKRESTORE:
753     return selectStackRestore(I);
754 
755   case TargetOpcode::G_UNMERGE_VALUES:
756     return selectUnmergeValues(I);
757 
758   // Discard gen opcodes for intrinsics which we do not expect to actually
759   // represent code after lowering or intrinsics which are not implemented but
760   // should not crash when found in a customer's LLVM IR input.
761   case TargetOpcode::G_TRAP:
762   case TargetOpcode::G_DEBUGTRAP:
763   case TargetOpcode::G_UBSANTRAP:
764   case TargetOpcode::DBG_LABEL:
765     return true;
766 
767   default:
768     return false;
769   }
770 }
771 
772 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
773                                              const SPIRVType *ResType,
774                                              MachineInstr &I,
775                                              CL::OpenCLExtInst CLInst) const {
776   return selectExtInst(ResVReg, ResType, I,
777                        {{SPIRV::InstructionSet::OpenCL_std, CLInst}});
778 }
779 
780 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
781                                              const SPIRVType *ResType,
782                                              MachineInstr &I,
783                                              CL::OpenCLExtInst CLInst,
784                                              GL::GLSLExtInst GLInst) const {
785   ExtInstList ExtInsts = {{SPIRV::InstructionSet::OpenCL_std, CLInst},
786                           {SPIRV::InstructionSet::GLSL_std_450, GLInst}};
787   return selectExtInst(ResVReg, ResType, I, ExtInsts);
788 }
789 
790 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
791                                              const SPIRVType *ResType,
792                                              MachineInstr &I,
793                                              const ExtInstList &Insts) const {
794 
795   for (const auto &Ex : Insts) {
796     SPIRV::InstructionSet::InstructionSet Set = Ex.first;
797     uint32_t Opcode = Ex.second;
798     if (STI.canUseExtInstSet(Set)) {
799       MachineBasicBlock &BB = *I.getParent();
800       auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
801                      .addDef(ResVReg)
802                      .addUse(GR.getSPIRVTypeID(ResType))
803                      .addImm(static_cast<uint32_t>(Set))
804                      .addImm(Opcode);
805       const unsigned NumOps = I.getNumOperands();
806       unsigned Index = 1;
807       if (Index < NumOps &&
808           I.getOperand(Index).getType() ==
809               MachineOperand::MachineOperandType::MO_IntrinsicID)
810         Index = 2;
811       for (; Index < NumOps; ++Index)
812         MIB.add(I.getOperand(Index));
813       return MIB.constrainAllUses(TII, TRI, RBI);
814     }
815   }
816   return false;
817 }
818 
819 bool SPIRVInstructionSelector::selectUnOpWithSrc(Register ResVReg,
820                                                  const SPIRVType *ResType,
821                                                  MachineInstr &I,
822                                                  Register SrcReg,
823                                                  unsigned Opcode) const {
824   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
825       .addDef(ResVReg)
826       .addUse(GR.getSPIRVTypeID(ResType))
827       .addUse(SrcReg)
828       .constrainAllUses(TII, TRI, RBI);
829 }
830 
831 bool SPIRVInstructionSelector::selectUnOp(Register ResVReg,
832                                           const SPIRVType *ResType,
833                                           MachineInstr &I,
834                                           unsigned Opcode) const {
835   if (STI.isOpenCLEnv() && I.getOperand(1).isReg()) {
836     Register SrcReg = I.getOperand(1).getReg();
837     bool IsGV = false;
838     for (MachineRegisterInfo::def_instr_iterator DefIt =
839              MRI->def_instr_begin(SrcReg);
840          DefIt != MRI->def_instr_end(); DefIt = std::next(DefIt)) {
841       if ((*DefIt).getOpcode() == TargetOpcode::G_GLOBAL_VALUE) {
842         IsGV = true;
843         break;
844       }
845     }
846     if (IsGV) {
847       uint32_t SpecOpcode = 0;
848       switch (Opcode) {
849       case SPIRV::OpConvertPtrToU:
850         SpecOpcode = static_cast<uint32_t>(SPIRV::Opcode::ConvertPtrToU);
851         break;
852       case SPIRV::OpConvertUToPtr:
853         SpecOpcode = static_cast<uint32_t>(SPIRV::Opcode::ConvertUToPtr);
854         break;
855       }
856       if (SpecOpcode)
857         return BuildMI(*I.getParent(), I, I.getDebugLoc(),
858                        TII.get(SPIRV::OpSpecConstantOp))
859             .addDef(ResVReg)
860             .addUse(GR.getSPIRVTypeID(ResType))
861             .addImm(SpecOpcode)
862             .addUse(SrcReg)
863             .constrainAllUses(TII, TRI, RBI);
864     }
865   }
866   return selectUnOpWithSrc(ResVReg, ResType, I, I.getOperand(1).getReg(),
867                            Opcode);
868 }
869 
870 bool SPIRVInstructionSelector::selectBitcast(Register ResVReg,
871                                              const SPIRVType *ResType,
872                                              MachineInstr &I) const {
873   Register OpReg = I.getOperand(1).getReg();
874   SPIRVType *OpType = OpReg.isValid() ? GR.getSPIRVTypeForVReg(OpReg) : nullptr;
875   if (!GR.isBitcastCompatible(ResType, OpType))
876     report_fatal_error("incompatible result and operand types in a bitcast");
877   return selectUnOp(ResVReg, ResType, I, SPIRV::OpBitcast);
878 }
879 
880 static void addMemoryOperands(MachineMemOperand *MemOp,
881                               MachineInstrBuilder &MIB) {
882   uint32_t SpvMemOp = static_cast<uint32_t>(SPIRV::MemoryOperand::None);
883   if (MemOp->isVolatile())
884     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Volatile);
885   if (MemOp->isNonTemporal())
886     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Nontemporal);
887   if (MemOp->getAlign().value())
888     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Aligned);
889 
890   if (SpvMemOp != static_cast<uint32_t>(SPIRV::MemoryOperand::None)) {
891     MIB.addImm(SpvMemOp);
892     if (SpvMemOp & static_cast<uint32_t>(SPIRV::MemoryOperand::Aligned))
893       MIB.addImm(MemOp->getAlign().value());
894   }
895 }
896 
897 static void addMemoryOperands(uint64_t Flags, MachineInstrBuilder &MIB) {
898   uint32_t SpvMemOp = static_cast<uint32_t>(SPIRV::MemoryOperand::None);
899   if (Flags & MachineMemOperand::Flags::MOVolatile)
900     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Volatile);
901   if (Flags & MachineMemOperand::Flags::MONonTemporal)
902     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Nontemporal);
903 
904   if (SpvMemOp != static_cast<uint32_t>(SPIRV::MemoryOperand::None))
905     MIB.addImm(SpvMemOp);
906 }
907 
908 bool SPIRVInstructionSelector::selectLoad(Register ResVReg,
909                                           const SPIRVType *ResType,
910                                           MachineInstr &I) const {
911   unsigned OpOffset = isa<GIntrinsic>(I) ? 1 : 0;
912   Register Ptr = I.getOperand(1 + OpOffset).getReg();
913   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
914                  .addDef(ResVReg)
915                  .addUse(GR.getSPIRVTypeID(ResType))
916                  .addUse(Ptr);
917   if (!I.getNumMemOperands()) {
918     assert(I.getOpcode() == TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS ||
919            I.getOpcode() ==
920                TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS);
921     addMemoryOperands(I.getOperand(2 + OpOffset).getImm(), MIB);
922   } else {
923     addMemoryOperands(*I.memoperands_begin(), MIB);
924   }
925   return MIB.constrainAllUses(TII, TRI, RBI);
926 }
927 
928 bool SPIRVInstructionSelector::selectStore(MachineInstr &I) const {
929   unsigned OpOffset = isa<GIntrinsic>(I) ? 1 : 0;
930   Register StoreVal = I.getOperand(0 + OpOffset).getReg();
931   Register Ptr = I.getOperand(1 + OpOffset).getReg();
932   MachineBasicBlock &BB = *I.getParent();
933   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpStore))
934                  .addUse(Ptr)
935                  .addUse(StoreVal);
936   if (!I.getNumMemOperands()) {
937     assert(I.getOpcode() == TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS ||
938            I.getOpcode() ==
939                TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS);
940     addMemoryOperands(I.getOperand(2 + OpOffset).getImm(), MIB);
941   } else {
942     addMemoryOperands(*I.memoperands_begin(), MIB);
943   }
944   return MIB.constrainAllUses(TII, TRI, RBI);
945 }
946 
947 bool SPIRVInstructionSelector::selectStackSave(Register ResVReg,
948                                                const SPIRVType *ResType,
949                                                MachineInstr &I) const {
950   if (!STI.canUseExtension(SPIRV::Extension::SPV_INTEL_variable_length_array))
951     report_fatal_error(
952         "llvm.stacksave intrinsic: this instruction requires the following "
953         "SPIR-V extension: SPV_INTEL_variable_length_array",
954         false);
955   MachineBasicBlock &BB = *I.getParent();
956   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSaveMemoryINTEL))
957       .addDef(ResVReg)
958       .addUse(GR.getSPIRVTypeID(ResType))
959       .constrainAllUses(TII, TRI, RBI);
960 }
961 
962 bool SPIRVInstructionSelector::selectStackRestore(MachineInstr &I) const {
963   if (!STI.canUseExtension(SPIRV::Extension::SPV_INTEL_variable_length_array))
964     report_fatal_error(
965         "llvm.stackrestore intrinsic: this instruction requires the following "
966         "SPIR-V extension: SPV_INTEL_variable_length_array",
967         false);
968   if (!I.getOperand(0).isReg())
969     return false;
970   MachineBasicBlock &BB = *I.getParent();
971   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpRestoreMemoryINTEL))
972       .addUse(I.getOperand(0).getReg())
973       .constrainAllUses(TII, TRI, RBI);
974 }
975 
976 bool SPIRVInstructionSelector::selectMemOperation(Register ResVReg,
977                                                   MachineInstr &I) const {
978   MachineBasicBlock &BB = *I.getParent();
979   Register SrcReg = I.getOperand(1).getReg();
980   if (I.getOpcode() == TargetOpcode::G_MEMSET) {
981     assert(I.getOperand(1).isReg() && I.getOperand(2).isReg());
982     unsigned Val = getIConstVal(I.getOperand(1).getReg(), MRI);
983     unsigned Num = getIConstVal(I.getOperand(2).getReg(), MRI);
984     SPIRVType *ValTy = GR.getOrCreateSPIRVIntegerType(8, I, TII);
985     SPIRVType *ArrTy = GR.getOrCreateSPIRVArrayType(ValTy, Num, I, TII);
986     Register Const = GR.getOrCreateConstIntArray(Val, Num, I, ArrTy, TII);
987     SPIRVType *VarTy = GR.getOrCreateSPIRVPointerType(
988         ArrTy, I, TII, SPIRV::StorageClass::UniformConstant);
989     // TODO: check if we have such GV, add init, use buildGlobalVariable.
990     Function &CurFunction = GR.CurMF->getFunction();
991     Type *LLVMArrTy =
992         ArrayType::get(IntegerType::get(CurFunction.getContext(), 8), Num);
993     // Module takes ownership of the global var.
994     GlobalVariable *GV = new GlobalVariable(*CurFunction.getParent(), LLVMArrTy,
995                                             true, GlobalValue::InternalLinkage,
996                                             Constant::getNullValue(LLVMArrTy));
997     Register VarReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
998     GR.add(GV, GR.CurMF, VarReg);
999 
1000     BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpVariable))
1001         .addDef(VarReg)
1002         .addUse(GR.getSPIRVTypeID(VarTy))
1003         .addImm(SPIRV::StorageClass::UniformConstant)
1004         .addUse(Const)
1005         .constrainAllUses(TII, TRI, RBI);
1006     buildOpDecorate(VarReg, I, TII, SPIRV::Decoration::Constant, {});
1007     SPIRVType *SourceTy = GR.getOrCreateSPIRVPointerType(
1008         ValTy, I, TII, SPIRV::StorageClass::UniformConstant);
1009     SrcReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1010     selectUnOpWithSrc(SrcReg, SourceTy, I, VarReg, SPIRV::OpBitcast);
1011   }
1012   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCopyMemorySized))
1013                  .addUse(I.getOperand(0).getReg())
1014                  .addUse(SrcReg)
1015                  .addUse(I.getOperand(2).getReg());
1016   if (I.getNumMemOperands())
1017     addMemoryOperands(*I.memoperands_begin(), MIB);
1018   bool Result = MIB.constrainAllUses(TII, TRI, RBI);
1019   if (ResVReg.isValid() && ResVReg != MIB->getOperand(0).getReg())
1020     BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY), ResVReg)
1021         .addUse(MIB->getOperand(0).getReg());
1022   return Result;
1023 }
1024 
1025 bool SPIRVInstructionSelector::selectAtomicRMW(Register ResVReg,
1026                                                const SPIRVType *ResType,
1027                                                MachineInstr &I,
1028                                                unsigned NewOpcode,
1029                                                unsigned NegateOpcode) const {
1030   assert(I.hasOneMemOperand());
1031   const MachineMemOperand *MemOp = *I.memoperands_begin();
1032   uint32_t Scope = static_cast<uint32_t>(getMemScope(
1033       GR.CurMF->getFunction().getContext(), MemOp->getSyncScopeID()));
1034   Register ScopeReg = buildI32Constant(Scope, I);
1035 
1036   Register Ptr = I.getOperand(1).getReg();
1037   // TODO: Changed as it's implemented in the translator. See test/atomicrmw.ll
1038   // auto ScSem =
1039   // getMemSemanticsForStorageClass(GR.getPointerStorageClass(Ptr));
1040   AtomicOrdering AO = MemOp->getSuccessOrdering();
1041   uint32_t MemSem = static_cast<uint32_t>(getMemSemantics(AO));
1042   Register MemSemReg = buildI32Constant(MemSem /*| ScSem*/, I);
1043 
1044   bool Result = false;
1045   Register ValueReg = I.getOperand(2).getReg();
1046   if (NegateOpcode != 0) {
1047     // Translation with negative value operand is requested
1048     Register TmpReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1049     Result |= selectUnOpWithSrc(TmpReg, ResType, I, ValueReg, NegateOpcode);
1050     ValueReg = TmpReg;
1051   }
1052 
1053   Result |= BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(NewOpcode))
1054                 .addDef(ResVReg)
1055                 .addUse(GR.getSPIRVTypeID(ResType))
1056                 .addUse(Ptr)
1057                 .addUse(ScopeReg)
1058                 .addUse(MemSemReg)
1059                 .addUse(ValueReg)
1060                 .constrainAllUses(TII, TRI, RBI);
1061   return Result;
1062 }
1063 
1064 bool SPIRVInstructionSelector::selectUnmergeValues(MachineInstr &I) const {
1065   unsigned ArgI = I.getNumOperands() - 1;
1066   Register SrcReg =
1067       I.getOperand(ArgI).isReg() ? I.getOperand(ArgI).getReg() : Register(0);
1068   SPIRVType *DefType =
1069       SrcReg.isValid() ? GR.getSPIRVTypeForVReg(SrcReg) : nullptr;
1070   if (!DefType || DefType->getOpcode() != SPIRV::OpTypeVector)
1071     report_fatal_error(
1072         "cannot select G_UNMERGE_VALUES with a non-vector argument");
1073 
1074   SPIRVType *ScalarType =
1075       GR.getSPIRVTypeForVReg(DefType->getOperand(1).getReg());
1076   MachineBasicBlock &BB = *I.getParent();
1077   bool Res = false;
1078   for (unsigned i = 0; i < I.getNumDefs(); ++i) {
1079     Register ResVReg = I.getOperand(i).getReg();
1080     SPIRVType *ResType = GR.getSPIRVTypeForVReg(ResVReg);
1081     if (!ResType) {
1082       // There was no "assign type" actions, let's fix this now
1083       ResType = ScalarType;
1084       MRI->setRegClass(ResVReg, GR.getRegClass(ResType));
1085       MRI->setType(ResVReg, LLT::scalar(GR.getScalarOrVectorBitWidth(ResType)));
1086       GR.assignSPIRVTypeToVReg(ResType, ResVReg, *GR.CurMF);
1087     }
1088     auto MIB =
1089         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1090             .addDef(ResVReg)
1091             .addUse(GR.getSPIRVTypeID(ResType))
1092             .addUse(SrcReg)
1093             .addImm(static_cast<int64_t>(i));
1094     Res |= MIB.constrainAllUses(TII, TRI, RBI);
1095   }
1096   return Res;
1097 }
1098 
1099 bool SPIRVInstructionSelector::selectFence(MachineInstr &I) const {
1100   AtomicOrdering AO = AtomicOrdering(I.getOperand(0).getImm());
1101   uint32_t MemSem = static_cast<uint32_t>(getMemSemantics(AO));
1102   Register MemSemReg = buildI32Constant(MemSem, I);
1103   SyncScope::ID Ord = SyncScope::ID(I.getOperand(1).getImm());
1104   uint32_t Scope = static_cast<uint32_t>(
1105       getMemScope(GR.CurMF->getFunction().getContext(), Ord));
1106   Register ScopeReg = buildI32Constant(Scope, I);
1107   MachineBasicBlock &BB = *I.getParent();
1108   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpMemoryBarrier))
1109       .addUse(ScopeReg)
1110       .addUse(MemSemReg)
1111       .constrainAllUses(TII, TRI, RBI);
1112 }
1113 
1114 bool SPIRVInstructionSelector::selectOverflowArith(Register ResVReg,
1115                                                    const SPIRVType *ResType,
1116                                                    MachineInstr &I,
1117                                                    unsigned Opcode) const {
1118   Type *ResTy = nullptr;
1119   StringRef ResName;
1120   if (!GR.findValueAttrs(&I, ResTy, ResName))
1121     report_fatal_error(
1122         "Not enough info to select the arithmetic with overflow instruction");
1123   if (!ResTy || !ResTy->isStructTy())
1124     report_fatal_error("Expect struct type result for the arithmetic "
1125                        "with overflow instruction");
1126   // "Result Type must be from OpTypeStruct. The struct must have two members,
1127   // and the two members must be the same type."
1128   Type *ResElemTy = cast<StructType>(ResTy)->getElementType(0);
1129   ResTy = StructType::create(SmallVector<Type *, 2>{ResElemTy, ResElemTy});
1130   // Build SPIR-V types and constant(s) if needed.
1131   MachineIRBuilder MIRBuilder(I);
1132   SPIRVType *StructType = GR.getOrCreateSPIRVType(
1133       ResTy, MIRBuilder, SPIRV::AccessQualifier::ReadWrite, false);
1134   assert(I.getNumDefs() > 1 && "Not enought operands");
1135   SPIRVType *BoolType = GR.getOrCreateSPIRVBoolType(I, TII);
1136   unsigned N = GR.getScalarOrVectorComponentCount(ResType);
1137   if (N > 1)
1138     BoolType = GR.getOrCreateSPIRVVectorType(BoolType, N, I, TII);
1139   Register BoolTypeReg = GR.getSPIRVTypeID(BoolType);
1140   Register ZeroReg = buildZerosVal(ResType, I);
1141   // A new virtual register to store the result struct.
1142   Register StructVReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1143   MRI->setRegClass(StructVReg, &SPIRV::IDRegClass);
1144   // Build the result name if needed.
1145   if (ResName.size() > 0)
1146     buildOpName(StructVReg, ResName, MIRBuilder);
1147   // Build the arithmetic with overflow instruction.
1148   MachineBasicBlock &BB = *I.getParent();
1149   auto MIB =
1150       BuildMI(BB, MIRBuilder.getInsertPt(), I.getDebugLoc(), TII.get(Opcode))
1151           .addDef(StructVReg)
1152           .addUse(GR.getSPIRVTypeID(StructType));
1153   for (unsigned i = I.getNumDefs(); i < I.getNumOperands(); ++i)
1154     MIB.addUse(I.getOperand(i).getReg());
1155   bool Status = MIB.constrainAllUses(TII, TRI, RBI);
1156   // Build instructions to extract fields of the instruction's result.
1157   // A new virtual register to store the higher part of the result struct.
1158   Register HigherVReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
1159   MRI->setRegClass(HigherVReg, &SPIRV::iIDRegClass);
1160   for (unsigned i = 0; i < I.getNumDefs(); ++i) {
1161     auto MIB =
1162         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1163             .addDef(i == 1 ? HigherVReg : I.getOperand(i).getReg())
1164             .addUse(GR.getSPIRVTypeID(ResType))
1165             .addUse(StructVReg)
1166             .addImm(i);
1167     Status &= MIB.constrainAllUses(TII, TRI, RBI);
1168   }
1169   // Build boolean value from the higher part.
1170   Status &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpINotEqual))
1171                 .addDef(I.getOperand(1).getReg())
1172                 .addUse(BoolTypeReg)
1173                 .addUse(HigherVReg)
1174                 .addUse(ZeroReg)
1175                 .constrainAllUses(TII, TRI, RBI);
1176   return Status;
1177 }
1178 
1179 bool SPIRVInstructionSelector::selectAtomicCmpXchg(Register ResVReg,
1180                                                    const SPIRVType *ResType,
1181                                                    MachineInstr &I) const {
1182   Register ScopeReg;
1183   Register MemSemEqReg;
1184   Register MemSemNeqReg;
1185   Register Ptr = I.getOperand(2).getReg();
1186   if (!isa<GIntrinsic>(I)) {
1187     assert(I.hasOneMemOperand());
1188     const MachineMemOperand *MemOp = *I.memoperands_begin();
1189     unsigned Scope = static_cast<uint32_t>(getMemScope(
1190         GR.CurMF->getFunction().getContext(), MemOp->getSyncScopeID()));
1191     ScopeReg = buildI32Constant(Scope, I);
1192 
1193     unsigned ScSem = static_cast<uint32_t>(
1194         getMemSemanticsForStorageClass(GR.getPointerStorageClass(Ptr)));
1195     AtomicOrdering AO = MemOp->getSuccessOrdering();
1196     unsigned MemSemEq = static_cast<uint32_t>(getMemSemantics(AO)) | ScSem;
1197     MemSemEqReg = buildI32Constant(MemSemEq, I);
1198     AtomicOrdering FO = MemOp->getFailureOrdering();
1199     unsigned MemSemNeq = static_cast<uint32_t>(getMemSemantics(FO)) | ScSem;
1200     MemSemNeqReg =
1201         MemSemEq == MemSemNeq ? MemSemEqReg : buildI32Constant(MemSemNeq, I);
1202   } else {
1203     ScopeReg = I.getOperand(5).getReg();
1204     MemSemEqReg = I.getOperand(6).getReg();
1205     MemSemNeqReg = I.getOperand(7).getReg();
1206   }
1207 
1208   Register Cmp = I.getOperand(3).getReg();
1209   Register Val = I.getOperand(4).getReg();
1210   SPIRVType *SpvValTy = GR.getSPIRVTypeForVReg(Val);
1211   Register ACmpRes = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1212   const DebugLoc &DL = I.getDebugLoc();
1213   bool Result =
1214       BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpAtomicCompareExchange))
1215           .addDef(ACmpRes)
1216           .addUse(GR.getSPIRVTypeID(SpvValTy))
1217           .addUse(Ptr)
1218           .addUse(ScopeReg)
1219           .addUse(MemSemEqReg)
1220           .addUse(MemSemNeqReg)
1221           .addUse(Val)
1222           .addUse(Cmp)
1223           .constrainAllUses(TII, TRI, RBI);
1224   Register CmpSuccReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1225   SPIRVType *BoolTy = GR.getOrCreateSPIRVBoolType(I, TII);
1226   Result |= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpIEqual))
1227                 .addDef(CmpSuccReg)
1228                 .addUse(GR.getSPIRVTypeID(BoolTy))
1229                 .addUse(ACmpRes)
1230                 .addUse(Cmp)
1231                 .constrainAllUses(TII, TRI, RBI);
1232   Register TmpReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1233   Result |= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpCompositeInsert))
1234                 .addDef(TmpReg)
1235                 .addUse(GR.getSPIRVTypeID(ResType))
1236                 .addUse(ACmpRes)
1237                 .addUse(GR.getOrCreateUndef(I, ResType, TII))
1238                 .addImm(0)
1239                 .constrainAllUses(TII, TRI, RBI);
1240   Result |= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpCompositeInsert))
1241                 .addDef(ResVReg)
1242                 .addUse(GR.getSPIRVTypeID(ResType))
1243                 .addUse(CmpSuccReg)
1244                 .addUse(TmpReg)
1245                 .addImm(1)
1246                 .constrainAllUses(TII, TRI, RBI);
1247   return Result;
1248 }
1249 
1250 static bool isGenericCastablePtr(SPIRV::StorageClass::StorageClass SC) {
1251   switch (SC) {
1252   case SPIRV::StorageClass::Workgroup:
1253   case SPIRV::StorageClass::CrossWorkgroup:
1254   case SPIRV::StorageClass::Function:
1255     return true;
1256   default:
1257     return false;
1258   }
1259 }
1260 
1261 static bool isUSMStorageClass(SPIRV::StorageClass::StorageClass SC) {
1262   switch (SC) {
1263   case SPIRV::StorageClass::DeviceOnlyINTEL:
1264   case SPIRV::StorageClass::HostOnlyINTEL:
1265     return true;
1266   default:
1267     return false;
1268   }
1269 }
1270 
1271 // Returns true ResVReg is referred only from global vars and OpName's.
1272 static bool isASCastInGVar(MachineRegisterInfo *MRI, Register ResVReg) {
1273   bool IsGRef = false;
1274   bool IsAllowedRefs =
1275       std::all_of(MRI->use_instr_begin(ResVReg), MRI->use_instr_end(),
1276                   [&IsGRef](auto const &It) {
1277                     unsigned Opcode = It.getOpcode();
1278                     if (Opcode == SPIRV::OpConstantComposite ||
1279                         Opcode == SPIRV::OpVariable ||
1280                         isSpvIntrinsic(It, Intrinsic::spv_init_global))
1281                       return IsGRef = true;
1282                     return Opcode == SPIRV::OpName;
1283                   });
1284   return IsAllowedRefs && IsGRef;
1285 }
1286 
1287 Register SPIRVInstructionSelector::getUcharPtrTypeReg(
1288     MachineInstr &I, SPIRV::StorageClass::StorageClass SC) const {
1289   return GR.getSPIRVTypeID(GR.getOrCreateSPIRVPointerType(
1290       GR.getOrCreateSPIRVIntegerType(8, I, TII), I, TII, SC));
1291 }
1292 
1293 MachineInstrBuilder
1294 SPIRVInstructionSelector::buildSpecConstantOp(MachineInstr &I, Register Dest,
1295                                               Register Src, Register DestType,
1296                                               uint32_t Opcode) const {
1297   return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1298                  TII.get(SPIRV::OpSpecConstantOp))
1299       .addDef(Dest)
1300       .addUse(DestType)
1301       .addImm(Opcode)
1302       .addUse(Src);
1303 }
1304 
1305 MachineInstrBuilder
1306 SPIRVInstructionSelector::buildConstGenericPtr(MachineInstr &I, Register SrcPtr,
1307                                                SPIRVType *SrcPtrTy) const {
1308   SPIRVType *GenericPtrTy = GR.getOrCreateSPIRVPointerType(
1309       GR.getPointeeType(SrcPtrTy), I, TII, SPIRV::StorageClass::Generic);
1310   Register Tmp = MRI->createVirtualRegister(&SPIRV::pIDRegClass);
1311   MRI->setType(Tmp, LLT::pointer(storageClassToAddressSpace(
1312                                      SPIRV::StorageClass::Generic),
1313                                  GR.getPointerSize()));
1314   MachineFunction *MF = I.getParent()->getParent();
1315   GR.assignSPIRVTypeToVReg(GenericPtrTy, Tmp, *MF);
1316   MachineInstrBuilder MIB = buildSpecConstantOp(
1317       I, Tmp, SrcPtr, GR.getSPIRVTypeID(GenericPtrTy),
1318       static_cast<uint32_t>(SPIRV::Opcode::PtrCastToGeneric));
1319   GR.add(MIB.getInstr(), MF, Tmp);
1320   return MIB;
1321 }
1322 
1323 // In SPIR-V address space casting can only happen to and from the Generic
1324 // storage class. We can also only cast Workgroup, CrossWorkgroup, or Function
1325 // pointers to and from Generic pointers. As such, we can convert e.g. from
1326 // Workgroup to Function by going via a Generic pointer as an intermediary. All
1327 // other combinations can only be done by a bitcast, and are probably not safe.
1328 bool SPIRVInstructionSelector::selectAddrSpaceCast(Register ResVReg,
1329                                                    const SPIRVType *ResType,
1330                                                    MachineInstr &I) const {
1331   MachineBasicBlock &BB = *I.getParent();
1332   const DebugLoc &DL = I.getDebugLoc();
1333 
1334   Register SrcPtr = I.getOperand(1).getReg();
1335   SPIRVType *SrcPtrTy = GR.getSPIRVTypeForVReg(SrcPtr);
1336 
1337   // don't generate a cast for a null that may be represented by OpTypeInt
1338   if (SrcPtrTy->getOpcode() != SPIRV::OpTypePointer ||
1339       ResType->getOpcode() != SPIRV::OpTypePointer)
1340     return BuildMI(BB, I, DL, TII.get(TargetOpcode::COPY))
1341         .addDef(ResVReg)
1342         .addUse(SrcPtr)
1343         .constrainAllUses(TII, TRI, RBI);
1344 
1345   SPIRV::StorageClass::StorageClass SrcSC = GR.getPointerStorageClass(SrcPtrTy);
1346   SPIRV::StorageClass::StorageClass DstSC = GR.getPointerStorageClass(ResType);
1347 
1348   if (isASCastInGVar(MRI, ResVReg)) {
1349     // AddrSpaceCast uses within OpVariable and OpConstantComposite instructions
1350     // are expressed by OpSpecConstantOp with an Opcode.
1351     // TODO: maybe insert a check whether the Kernel capability was declared and
1352     // so PtrCastToGeneric/GenericCastToPtr are available.
1353     unsigned SpecOpcode =
1354         DstSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(SrcSC)
1355             ? static_cast<uint32_t>(SPIRV::Opcode::PtrCastToGeneric)
1356             : (SrcSC == SPIRV::StorageClass::Generic &&
1357                        isGenericCastablePtr(DstSC)
1358                    ? static_cast<uint32_t>(SPIRV::Opcode::GenericCastToPtr)
1359                    : 0);
1360     // TODO: OpConstantComposite expects i8*, so we are forced to forget a
1361     // correct value of ResType and use general i8* instead. Maybe this should
1362     // be addressed in the emit-intrinsic step to infer a correct
1363     // OpConstantComposite type.
1364     if (SpecOpcode) {
1365       return buildSpecConstantOp(I, ResVReg, SrcPtr,
1366                                  getUcharPtrTypeReg(I, DstSC), SpecOpcode)
1367           .constrainAllUses(TII, TRI, RBI);
1368     } else if (isGenericCastablePtr(SrcSC) && isGenericCastablePtr(DstSC)) {
1369       MachineInstrBuilder MIB = buildConstGenericPtr(I, SrcPtr, SrcPtrTy);
1370       return MIB.constrainAllUses(TII, TRI, RBI) &&
1371              buildSpecConstantOp(
1372                  I, ResVReg, MIB->getOperand(0).getReg(),
1373                  getUcharPtrTypeReg(I, DstSC),
1374                  static_cast<uint32_t>(SPIRV::Opcode::GenericCastToPtr))
1375                  .constrainAllUses(TII, TRI, RBI);
1376     }
1377   }
1378 
1379   // don't generate a cast between identical storage classes
1380   if (SrcSC == DstSC)
1381     return BuildMI(BB, I, DL, TII.get(TargetOpcode::COPY))
1382         .addDef(ResVReg)
1383         .addUse(SrcPtr)
1384         .constrainAllUses(TII, TRI, RBI);
1385 
1386   // Casting from an eligible pointer to Generic.
1387   if (DstSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(SrcSC))
1388     return selectUnOp(ResVReg, ResType, I, SPIRV::OpPtrCastToGeneric);
1389   // Casting from Generic to an eligible pointer.
1390   if (SrcSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(DstSC))
1391     return selectUnOp(ResVReg, ResType, I, SPIRV::OpGenericCastToPtr);
1392   // Casting between 2 eligible pointers using Generic as an intermediary.
1393   if (isGenericCastablePtr(SrcSC) && isGenericCastablePtr(DstSC)) {
1394     Register Tmp = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1395     SPIRVType *GenericPtrTy = GR.getOrCreateSPIRVPointerType(
1396         GR.getPointeeType(SrcPtrTy), I, TII, SPIRV::StorageClass::Generic);
1397     bool Success = BuildMI(BB, I, DL, TII.get(SPIRV::OpPtrCastToGeneric))
1398                        .addDef(Tmp)
1399                        .addUse(GR.getSPIRVTypeID(GenericPtrTy))
1400                        .addUse(SrcPtr)
1401                        .constrainAllUses(TII, TRI, RBI);
1402     return Success && BuildMI(BB, I, DL, TII.get(SPIRV::OpGenericCastToPtr))
1403                           .addDef(ResVReg)
1404                           .addUse(GR.getSPIRVTypeID(ResType))
1405                           .addUse(Tmp)
1406                           .constrainAllUses(TII, TRI, RBI);
1407   }
1408 
1409   // Check if instructions from the SPV_INTEL_usm_storage_classes extension may
1410   // be applied
1411   if (isUSMStorageClass(SrcSC) && DstSC == SPIRV::StorageClass::CrossWorkgroup)
1412     return selectUnOp(ResVReg, ResType, I,
1413                       SPIRV::OpPtrCastToCrossWorkgroupINTEL);
1414   if (SrcSC == SPIRV::StorageClass::CrossWorkgroup && isUSMStorageClass(DstSC))
1415     return selectUnOp(ResVReg, ResType, I,
1416                       SPIRV::OpCrossWorkgroupCastToPtrINTEL);
1417   if (isUSMStorageClass(SrcSC) && DstSC == SPIRV::StorageClass::Generic)
1418     return selectUnOp(ResVReg, ResType, I, SPIRV::OpPtrCastToGeneric);
1419   if (SrcSC == SPIRV::StorageClass::Generic && isUSMStorageClass(DstSC))
1420     return selectUnOp(ResVReg, ResType, I, SPIRV::OpGenericCastToPtr);
1421 
1422   // Bitcast for pointers requires that the address spaces must match
1423   return false;
1424 }
1425 
1426 static unsigned getFCmpOpcode(unsigned PredNum) {
1427   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1428   switch (Pred) {
1429   case CmpInst::FCMP_OEQ:
1430     return SPIRV::OpFOrdEqual;
1431   case CmpInst::FCMP_OGE:
1432     return SPIRV::OpFOrdGreaterThanEqual;
1433   case CmpInst::FCMP_OGT:
1434     return SPIRV::OpFOrdGreaterThan;
1435   case CmpInst::FCMP_OLE:
1436     return SPIRV::OpFOrdLessThanEqual;
1437   case CmpInst::FCMP_OLT:
1438     return SPIRV::OpFOrdLessThan;
1439   case CmpInst::FCMP_ONE:
1440     return SPIRV::OpFOrdNotEqual;
1441   case CmpInst::FCMP_ORD:
1442     return SPIRV::OpOrdered;
1443   case CmpInst::FCMP_UEQ:
1444     return SPIRV::OpFUnordEqual;
1445   case CmpInst::FCMP_UGE:
1446     return SPIRV::OpFUnordGreaterThanEqual;
1447   case CmpInst::FCMP_UGT:
1448     return SPIRV::OpFUnordGreaterThan;
1449   case CmpInst::FCMP_ULE:
1450     return SPIRV::OpFUnordLessThanEqual;
1451   case CmpInst::FCMP_ULT:
1452     return SPIRV::OpFUnordLessThan;
1453   case CmpInst::FCMP_UNE:
1454     return SPIRV::OpFUnordNotEqual;
1455   case CmpInst::FCMP_UNO:
1456     return SPIRV::OpUnordered;
1457   default:
1458     llvm_unreachable("Unknown predicate type for FCmp");
1459   }
1460 }
1461 
1462 static unsigned getICmpOpcode(unsigned PredNum) {
1463   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1464   switch (Pred) {
1465   case CmpInst::ICMP_EQ:
1466     return SPIRV::OpIEqual;
1467   case CmpInst::ICMP_NE:
1468     return SPIRV::OpINotEqual;
1469   case CmpInst::ICMP_SGE:
1470     return SPIRV::OpSGreaterThanEqual;
1471   case CmpInst::ICMP_SGT:
1472     return SPIRV::OpSGreaterThan;
1473   case CmpInst::ICMP_SLE:
1474     return SPIRV::OpSLessThanEqual;
1475   case CmpInst::ICMP_SLT:
1476     return SPIRV::OpSLessThan;
1477   case CmpInst::ICMP_UGE:
1478     return SPIRV::OpUGreaterThanEqual;
1479   case CmpInst::ICMP_UGT:
1480     return SPIRV::OpUGreaterThan;
1481   case CmpInst::ICMP_ULE:
1482     return SPIRV::OpULessThanEqual;
1483   case CmpInst::ICMP_ULT:
1484     return SPIRV::OpULessThan;
1485   default:
1486     llvm_unreachable("Unknown predicate type for ICmp");
1487   }
1488 }
1489 
1490 static unsigned getPtrCmpOpcode(unsigned Pred) {
1491   switch (static_cast<CmpInst::Predicate>(Pred)) {
1492   case CmpInst::ICMP_EQ:
1493     return SPIRV::OpPtrEqual;
1494   case CmpInst::ICMP_NE:
1495     return SPIRV::OpPtrNotEqual;
1496   default:
1497     llvm_unreachable("Unknown predicate type for pointer comparison");
1498   }
1499 }
1500 
1501 // Return the logical operation, or abort if none exists.
1502 static unsigned getBoolCmpOpcode(unsigned PredNum) {
1503   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1504   switch (Pred) {
1505   case CmpInst::ICMP_EQ:
1506     return SPIRV::OpLogicalEqual;
1507   case CmpInst::ICMP_NE:
1508     return SPIRV::OpLogicalNotEqual;
1509   default:
1510     llvm_unreachable("Unknown predicate type for Bool comparison");
1511   }
1512 }
1513 
1514 static APFloat getZeroFP(const Type *LLVMFloatTy) {
1515   if (!LLVMFloatTy)
1516     return APFloat::getZero(APFloat::IEEEsingle());
1517   switch (LLVMFloatTy->getScalarType()->getTypeID()) {
1518   case Type::HalfTyID:
1519     return APFloat::getZero(APFloat::IEEEhalf());
1520   default:
1521   case Type::FloatTyID:
1522     return APFloat::getZero(APFloat::IEEEsingle());
1523   case Type::DoubleTyID:
1524     return APFloat::getZero(APFloat::IEEEdouble());
1525   }
1526 }
1527 
1528 static APFloat getOneFP(const Type *LLVMFloatTy) {
1529   if (!LLVMFloatTy)
1530     return APFloat::getOne(APFloat::IEEEsingle());
1531   switch (LLVMFloatTy->getScalarType()->getTypeID()) {
1532   case Type::HalfTyID:
1533     return APFloat::getOne(APFloat::IEEEhalf());
1534   default:
1535   case Type::FloatTyID:
1536     return APFloat::getOne(APFloat::IEEEsingle());
1537   case Type::DoubleTyID:
1538     return APFloat::getOne(APFloat::IEEEdouble());
1539   }
1540 }
1541 
1542 bool SPIRVInstructionSelector::selectAnyOrAll(Register ResVReg,
1543                                               const SPIRVType *ResType,
1544                                               MachineInstr &I,
1545                                               unsigned OpAnyOrAll) const {
1546   assert(I.getNumOperands() == 3);
1547   assert(I.getOperand(2).isReg());
1548   MachineBasicBlock &BB = *I.getParent();
1549   Register InputRegister = I.getOperand(2).getReg();
1550   SPIRVType *InputType = GR.getSPIRVTypeForVReg(InputRegister);
1551 
1552   if (!InputType)
1553     report_fatal_error("Input Type could not be determined.");
1554 
1555   bool IsBoolTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeBool);
1556   bool IsVectorTy = InputType->getOpcode() == SPIRV::OpTypeVector;
1557   if (IsBoolTy && !IsVectorTy) {
1558     assert(ResVReg == I.getOperand(0).getReg());
1559     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1560                    TII.get(TargetOpcode::COPY))
1561         .addDef(ResVReg)
1562         .addUse(InputRegister)
1563         .constrainAllUses(TII, TRI, RBI);
1564   }
1565 
1566   bool IsFloatTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeFloat);
1567   unsigned SpirvNotEqualId =
1568       IsFloatTy ? SPIRV::OpFOrdNotEqual : SPIRV::OpINotEqual;
1569   SPIRVType *SpvBoolScalarTy = GR.getOrCreateSPIRVBoolType(I, TII);
1570   SPIRVType *SpvBoolTy = SpvBoolScalarTy;
1571   Register NotEqualReg = ResVReg;
1572 
1573   if (IsVectorTy) {
1574     NotEqualReg = IsBoolTy ? InputRegister
1575                            : MRI->createVirtualRegister(&SPIRV::iIDRegClass);
1576     const unsigned NumElts = InputType->getOperand(2).getImm();
1577     SpvBoolTy = GR.getOrCreateSPIRVVectorType(SpvBoolTy, NumElts, I, TII);
1578   }
1579 
1580   if (!IsBoolTy) {
1581     Register ConstZeroReg =
1582         IsFloatTy ? buildZerosValF(InputType, I) : buildZerosVal(InputType, I);
1583 
1584     BuildMI(BB, I, I.getDebugLoc(), TII.get(SpirvNotEqualId))
1585         .addDef(NotEqualReg)
1586         .addUse(GR.getSPIRVTypeID(SpvBoolTy))
1587         .addUse(InputRegister)
1588         .addUse(ConstZeroReg)
1589         .constrainAllUses(TII, TRI, RBI);
1590   }
1591 
1592   if (!IsVectorTy)
1593     return true;
1594 
1595   return BuildMI(BB, I, I.getDebugLoc(), TII.get(OpAnyOrAll))
1596       .addDef(ResVReg)
1597       .addUse(GR.getSPIRVTypeID(SpvBoolScalarTy))
1598       .addUse(NotEqualReg)
1599       .constrainAllUses(TII, TRI, RBI);
1600 }
1601 
1602 bool SPIRVInstructionSelector::selectAll(Register ResVReg,
1603                                          const SPIRVType *ResType,
1604                                          MachineInstr &I) const {
1605   return selectAnyOrAll(ResVReg, ResType, I, SPIRV::OpAll);
1606 }
1607 
1608 bool SPIRVInstructionSelector::selectAny(Register ResVReg,
1609                                          const SPIRVType *ResType,
1610                                          MachineInstr &I) const {
1611   return selectAnyOrAll(ResVReg, ResType, I, SPIRV::OpAny);
1612 }
1613 
1614 // Select the OpDot instruction for the given float dot
1615 bool SPIRVInstructionSelector::selectFloatDot(Register ResVReg,
1616                                               const SPIRVType *ResType,
1617                                               MachineInstr &I) const {
1618   assert(I.getNumOperands() == 4);
1619   assert(I.getOperand(2).isReg());
1620   assert(I.getOperand(3).isReg());
1621 
1622   [[maybe_unused]] SPIRVType *VecType =
1623       GR.getSPIRVTypeForVReg(I.getOperand(2).getReg());
1624 
1625   assert(VecType->getOpcode() == SPIRV::OpTypeVector &&
1626          GR.getScalarOrVectorComponentCount(VecType) > 1 &&
1627          "dot product requires a vector of at least 2 components");
1628 
1629   [[maybe_unused]] SPIRVType *EltType =
1630       GR.getSPIRVTypeForVReg(VecType->getOperand(1).getReg());
1631 
1632   assert(EltType->getOpcode() == SPIRV::OpTypeFloat);
1633 
1634   MachineBasicBlock &BB = *I.getParent();
1635   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpDot))
1636       .addDef(ResVReg)
1637       .addUse(GR.getSPIRVTypeID(ResType))
1638       .addUse(I.getOperand(2).getReg())
1639       .addUse(I.getOperand(3).getReg())
1640       .constrainAllUses(TII, TRI, RBI);
1641 }
1642 
1643 // Since pre-1.6 SPIRV has no integer dot implementation,
1644 // expand by piecewise multiplying and adding the results
1645 bool SPIRVInstructionSelector::selectIntegerDot(Register ResVReg,
1646                                                 const SPIRVType *ResType,
1647                                                 MachineInstr &I) const {
1648   assert(I.getNumOperands() == 4);
1649   assert(I.getOperand(2).isReg());
1650   assert(I.getOperand(3).isReg());
1651   MachineBasicBlock &BB = *I.getParent();
1652 
1653   // Multiply the vectors, then sum the results
1654   Register Vec0 = I.getOperand(2).getReg();
1655   Register Vec1 = I.getOperand(3).getReg();
1656   Register TmpVec = MRI->createVirtualRegister(GR.getRegClass(ResType));
1657   SPIRVType *VecType = GR.getSPIRVTypeForVReg(Vec0);
1658 
1659   bool Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIMulV))
1660                     .addDef(TmpVec)
1661                     .addUse(GR.getSPIRVTypeID(VecType))
1662                     .addUse(Vec0)
1663                     .addUse(Vec1)
1664                     .constrainAllUses(TII, TRI, RBI);
1665 
1666   assert(VecType->getOpcode() == SPIRV::OpTypeVector &&
1667          GR.getScalarOrVectorComponentCount(VecType) > 1 &&
1668          "dot product requires a vector of at least 2 components");
1669 
1670   Register Res = MRI->createVirtualRegister(GR.getRegClass(ResType));
1671   Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1672                 .addDef(Res)
1673                 .addUse(GR.getSPIRVTypeID(ResType))
1674                 .addUse(TmpVec)
1675                 .addImm(0)
1676                 .constrainAllUses(TII, TRI, RBI);
1677 
1678   for (unsigned i = 1; i < GR.getScalarOrVectorComponentCount(VecType); i++) {
1679     Register Elt = MRI->createVirtualRegister(GR.getRegClass(ResType));
1680 
1681     Result &=
1682         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1683             .addDef(Elt)
1684             .addUse(GR.getSPIRVTypeID(ResType))
1685             .addUse(TmpVec)
1686             .addImm(i)
1687             .constrainAllUses(TII, TRI, RBI);
1688 
1689     Register Sum = i < GR.getScalarOrVectorComponentCount(VecType) - 1
1690                        ? MRI->createVirtualRegister(GR.getRegClass(ResType))
1691                        : ResVReg;
1692 
1693     Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIAddS))
1694                   .addDef(Sum)
1695                   .addUse(GR.getSPIRVTypeID(ResType))
1696                   .addUse(Res)
1697                   .addUse(Elt)
1698                   .constrainAllUses(TII, TRI, RBI);
1699     Res = Sum;
1700   }
1701 
1702   return Result;
1703 }
1704 
1705 template <bool Signed>
1706 bool SPIRVInstructionSelector::selectDot4AddPacked(Register ResVReg,
1707                                                    const SPIRVType *ResType,
1708                                                    MachineInstr &I) const {
1709   assert(I.getNumOperands() == 5);
1710   assert(I.getOperand(2).isReg());
1711   assert(I.getOperand(3).isReg());
1712   assert(I.getOperand(4).isReg());
1713   MachineBasicBlock &BB = *I.getParent();
1714 
1715   auto DotOp = Signed ? SPIRV::OpSDot : SPIRV::OpUDot;
1716   Register Dot = MRI->createVirtualRegister(GR.getRegClass(ResType));
1717   bool Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(DotOp))
1718                     .addDef(Dot)
1719                     .addUse(GR.getSPIRVTypeID(ResType))
1720                     .addUse(I.getOperand(2).getReg())
1721                     .addUse(I.getOperand(3).getReg())
1722                     .constrainAllUses(TII, TRI, RBI);
1723 
1724   Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIAddS))
1725                 .addDef(ResVReg)
1726                 .addUse(GR.getSPIRVTypeID(ResType))
1727                 .addUse(Dot)
1728                 .addUse(I.getOperand(4).getReg())
1729                 .constrainAllUses(TII, TRI, RBI);
1730 
1731   return Result;
1732 }
1733 
1734 // Since pre-1.6 SPIRV has no DotProductInput4x8BitPacked implementation,
1735 // extract the elements of the packed inputs, multiply them and add the result
1736 // to the accumulator.
1737 template <bool Signed>
1738 bool SPIRVInstructionSelector::selectDot4AddPackedExpansion(
1739     Register ResVReg, const SPIRVType *ResType, MachineInstr &I) const {
1740   assert(I.getNumOperands() == 5);
1741   assert(I.getOperand(2).isReg());
1742   assert(I.getOperand(3).isReg());
1743   assert(I.getOperand(4).isReg());
1744   MachineBasicBlock &BB = *I.getParent();
1745 
1746   bool Result = false;
1747 
1748   // Acc = C
1749   Register Acc = I.getOperand(4).getReg();
1750   SPIRVType *EltType = GR.getOrCreateSPIRVIntegerType(8, I, TII);
1751   auto ExtractOp =
1752       Signed ? SPIRV::OpBitFieldSExtract : SPIRV::OpBitFieldUExtract;
1753 
1754   // Extract the i8 element, multiply and add it to the accumulator
1755   for (unsigned i = 0; i < 4; i++) {
1756     // A[i]
1757     Register AElt = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1758     Result |= BuildMI(BB, I, I.getDebugLoc(), TII.get(ExtractOp))
1759                   .addDef(AElt)
1760                   .addUse(GR.getSPIRVTypeID(ResType))
1761                   .addUse(I.getOperand(2).getReg())
1762                   .addUse(GR.getOrCreateConstInt(i * 8, I, EltType, TII))
1763                   .addUse(GR.getOrCreateConstInt(8, I, EltType, TII))
1764                   .constrainAllUses(TII, TRI, RBI);
1765 
1766     // B[i]
1767     Register BElt = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1768     Result |= BuildMI(BB, I, I.getDebugLoc(), TII.get(ExtractOp))
1769                   .addDef(BElt)
1770                   .addUse(GR.getSPIRVTypeID(ResType))
1771                   .addUse(I.getOperand(3).getReg())
1772                   .addUse(GR.getOrCreateConstInt(i * 8, I, EltType, TII))
1773                   .addUse(GR.getOrCreateConstInt(8, I, EltType, TII))
1774                   .constrainAllUses(TII, TRI, RBI);
1775 
1776     // A[i] * B[i]
1777     Register Mul = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1778     Result |= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIMulS))
1779                   .addDef(Mul)
1780                   .addUse(GR.getSPIRVTypeID(ResType))
1781                   .addUse(AElt)
1782                   .addUse(BElt)
1783                   .constrainAllUses(TII, TRI, RBI);
1784 
1785     // Discard 24 highest-bits so that stored i32 register is i8 equivalent
1786     Register MaskMul = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1787     Result |= BuildMI(BB, I, I.getDebugLoc(), TII.get(ExtractOp))
1788                   .addDef(MaskMul)
1789                   .addUse(GR.getSPIRVTypeID(ResType))
1790                   .addUse(Mul)
1791                   .addUse(GR.getOrCreateConstInt(0, I, EltType, TII))
1792                   .addUse(GR.getOrCreateConstInt(8, I, EltType, TII))
1793                   .constrainAllUses(TII, TRI, RBI);
1794 
1795     // Acc = Acc + A[i] * B[i]
1796     Register Sum =
1797         i < 3 ? MRI->createVirtualRegister(&SPIRV::IDRegClass) : ResVReg;
1798     Result |= BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpIAddS))
1799                   .addDef(Sum)
1800                   .addUse(GR.getSPIRVTypeID(ResType))
1801                   .addUse(Acc)
1802                   .addUse(MaskMul)
1803                   .constrainAllUses(TII, TRI, RBI);
1804 
1805     Acc = Sum;
1806   }
1807 
1808   return Result;
1809 }
1810 
1811 /// Transform saturate(x) to clamp(x, 0.0f, 1.0f) as SPIRV
1812 /// does not have a saturate builtin.
1813 bool SPIRVInstructionSelector::selectSaturate(Register ResVReg,
1814                                               const SPIRVType *ResType,
1815                                               MachineInstr &I) const {
1816   assert(I.getNumOperands() == 3);
1817   assert(I.getOperand(2).isReg());
1818   MachineBasicBlock &BB = *I.getParent();
1819   Register VZero = buildZerosValF(ResType, I);
1820   Register VOne = buildOnesValF(ResType, I);
1821 
1822   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
1823       .addDef(ResVReg)
1824       .addUse(GR.getSPIRVTypeID(ResType))
1825       .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
1826       .addImm(GL::FClamp)
1827       .addUse(I.getOperand(2).getReg())
1828       .addUse(VZero)
1829       .addUse(VOne)
1830       .constrainAllUses(TII, TRI, RBI);
1831 }
1832 
1833 bool SPIRVInstructionSelector::selectSign(Register ResVReg,
1834                                           const SPIRVType *ResType,
1835                                           MachineInstr &I) const {
1836   assert(I.getNumOperands() == 3);
1837   assert(I.getOperand(2).isReg());
1838   MachineBasicBlock &BB = *I.getParent();
1839   Register InputRegister = I.getOperand(2).getReg();
1840   SPIRVType *InputType = GR.getSPIRVTypeForVReg(InputRegister);
1841   auto &DL = I.getDebugLoc();
1842 
1843   if (!InputType)
1844     report_fatal_error("Input Type could not be determined.");
1845 
1846   bool IsFloatTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeFloat);
1847 
1848   unsigned SignBitWidth = GR.getScalarOrVectorBitWidth(InputType);
1849   unsigned ResBitWidth = GR.getScalarOrVectorBitWidth(ResType);
1850 
1851   bool NeedsConversion = IsFloatTy || SignBitWidth != ResBitWidth;
1852 
1853   auto SignOpcode = IsFloatTy ? GL::FSign : GL::SSign;
1854   Register SignReg = NeedsConversion
1855                          ? MRI->createVirtualRegister(&SPIRV::IDRegClass)
1856                          : ResVReg;
1857 
1858   bool Result =
1859       BuildMI(BB, I, DL, TII.get(SPIRV::OpExtInst))
1860           .addDef(SignReg)
1861           .addUse(GR.getSPIRVTypeID(InputType))
1862           .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
1863           .addImm(SignOpcode)
1864           .addUse(InputRegister)
1865           .constrainAllUses(TII, TRI, RBI);
1866 
1867   if (NeedsConversion) {
1868     auto ConvertOpcode = IsFloatTy ? SPIRV::OpConvertFToS : SPIRV::OpSConvert;
1869     Result |= BuildMI(*I.getParent(), I, DL, TII.get(ConvertOpcode))
1870                   .addDef(ResVReg)
1871                   .addUse(GR.getSPIRVTypeID(ResType))
1872                   .addUse(SignReg)
1873                   .constrainAllUses(TII, TRI, RBI);
1874   }
1875 
1876   return Result;
1877 }
1878 
1879 bool SPIRVInstructionSelector::selectWaveReadLaneAt(Register ResVReg,
1880                                                     const SPIRVType *ResType,
1881                                                     MachineInstr &I) const {
1882   assert(I.getNumOperands() == 4);
1883   assert(I.getOperand(2).isReg());
1884   assert(I.getOperand(3).isReg());
1885   MachineBasicBlock &BB = *I.getParent();
1886 
1887   // IntTy is used to define the execution scope, set to 3 to denote a
1888   // cross-lane interaction equivalent to a SPIR-V subgroup.
1889   SPIRVType *IntTy = GR.getOrCreateSPIRVIntegerType(32, I, TII);
1890   return BuildMI(BB, I, I.getDebugLoc(),
1891                  TII.get(SPIRV::OpGroupNonUniformShuffle))
1892       .addDef(ResVReg)
1893       .addUse(GR.getSPIRVTypeID(ResType))
1894       .addUse(GR.getOrCreateConstInt(3, I, IntTy, TII))
1895       .addUse(I.getOperand(2).getReg())
1896       .addUse(I.getOperand(3).getReg());
1897 }
1898 
1899 bool SPIRVInstructionSelector::selectBitreverse(Register ResVReg,
1900                                                 const SPIRVType *ResType,
1901                                                 MachineInstr &I) const {
1902   MachineBasicBlock &BB = *I.getParent();
1903   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpBitReverse))
1904       .addDef(ResVReg)
1905       .addUse(GR.getSPIRVTypeID(ResType))
1906       .addUse(I.getOperand(1).getReg())
1907       .constrainAllUses(TII, TRI, RBI);
1908 }
1909 
1910 bool SPIRVInstructionSelector::selectFreeze(Register ResVReg,
1911                                             const SPIRVType *ResType,
1912                                             MachineInstr &I) const {
1913   // There is no way to implement `freeze` correctly without support on SPIR-V
1914   // standard side, but we may at least address a simple (static) case when
1915   // undef/poison value presence is obvious. The main benefit of even
1916   // incomplete `freeze` support is preventing of translation from crashing due
1917   // to lack of support on legalization and instruction selection steps.
1918   if (!I.getOperand(0).isReg() || !I.getOperand(1).isReg())
1919     return false;
1920   Register OpReg = I.getOperand(1).getReg();
1921   if (MachineInstr *Def = MRI->getVRegDef(OpReg)) {
1922     Register Reg;
1923     switch (Def->getOpcode()) {
1924     case SPIRV::ASSIGN_TYPE:
1925       if (MachineInstr *AssignToDef =
1926               MRI->getVRegDef(Def->getOperand(1).getReg())) {
1927         if (AssignToDef->getOpcode() == TargetOpcode::G_IMPLICIT_DEF)
1928           Reg = Def->getOperand(2).getReg();
1929       }
1930       break;
1931     case SPIRV::OpUndef:
1932       Reg = Def->getOperand(1).getReg();
1933       break;
1934     }
1935     unsigned DestOpCode;
1936     if (Reg.isValid()) {
1937       DestOpCode = SPIRV::OpConstantNull;
1938     } else {
1939       DestOpCode = TargetOpcode::COPY;
1940       Reg = OpReg;
1941     }
1942     return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(DestOpCode))
1943         .addDef(I.getOperand(0).getReg())
1944         .addUse(Reg)
1945         .constrainAllUses(TII, TRI, RBI);
1946   }
1947   return false;
1948 }
1949 
1950 static unsigned getArrayComponentCount(MachineRegisterInfo *MRI,
1951                                        const SPIRVType *ResType) {
1952   Register OpReg = ResType->getOperand(2).getReg();
1953   SPIRVType *OpDef = MRI->getVRegDef(OpReg);
1954   if (!OpDef)
1955     return 0;
1956   if (OpDef->getOpcode() == SPIRV::ASSIGN_TYPE &&
1957       OpDef->getOperand(1).isReg()) {
1958     if (SPIRVType *RefDef = MRI->getVRegDef(OpDef->getOperand(1).getReg()))
1959       OpDef = RefDef;
1960   }
1961   unsigned N = OpDef->getOpcode() == TargetOpcode::G_CONSTANT
1962                    ? OpDef->getOperand(1).getCImm()->getValue().getZExtValue()
1963                    : 0;
1964   return N;
1965 }
1966 
1967 // Return true if the type represents a constant register
1968 static bool isConstReg(MachineRegisterInfo *MRI, SPIRVType *OpDef,
1969                        SmallPtrSet<SPIRVType *, 4> &Visited) {
1970   if (OpDef->getOpcode() == SPIRV::ASSIGN_TYPE &&
1971       OpDef->getOperand(1).isReg()) {
1972     if (SPIRVType *RefDef = MRI->getVRegDef(OpDef->getOperand(1).getReg()))
1973       OpDef = RefDef;
1974   }
1975 
1976   if (Visited.contains(OpDef))
1977     return true;
1978   Visited.insert(OpDef);
1979 
1980   unsigned Opcode = OpDef->getOpcode();
1981   switch (Opcode) {
1982   case TargetOpcode::G_CONSTANT:
1983   case TargetOpcode::G_FCONSTANT:
1984     return true;
1985   case TargetOpcode::G_INTRINSIC:
1986   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
1987   case TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS:
1988     return cast<GIntrinsic>(*OpDef).getIntrinsicID() ==
1989            Intrinsic::spv_const_composite;
1990   case TargetOpcode::G_BUILD_VECTOR:
1991   case TargetOpcode::G_SPLAT_VECTOR: {
1992     for (unsigned i = OpDef->getNumExplicitDefs(); i < OpDef->getNumOperands();
1993          i++) {
1994       SPIRVType *OpNestedDef =
1995           OpDef->getOperand(i).isReg()
1996               ? MRI->getVRegDef(OpDef->getOperand(i).getReg())
1997               : nullptr;
1998       if (OpNestedDef && !isConstReg(MRI, OpNestedDef, Visited))
1999         return false;
2000     }
2001     return true;
2002   }
2003   }
2004   return false;
2005 }
2006 
2007 // Return true if the virtual register represents a constant
2008 static bool isConstReg(MachineRegisterInfo *MRI, Register OpReg) {
2009   SmallPtrSet<SPIRVType *, 4> Visited;
2010   if (SPIRVType *OpDef = MRI->getVRegDef(OpReg))
2011     return isConstReg(MRI, OpDef, Visited);
2012   return false;
2013 }
2014 
2015 bool SPIRVInstructionSelector::selectBuildVector(Register ResVReg,
2016                                                  const SPIRVType *ResType,
2017                                                  MachineInstr &I) const {
2018   unsigned N = 0;
2019   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2020     N = GR.getScalarOrVectorComponentCount(ResType);
2021   else if (ResType->getOpcode() == SPIRV::OpTypeArray)
2022     N = getArrayComponentCount(MRI, ResType);
2023   else
2024     report_fatal_error("Cannot select G_BUILD_VECTOR with a non-vector result");
2025   if (I.getNumExplicitOperands() - I.getNumExplicitDefs() != N)
2026     report_fatal_error("G_BUILD_VECTOR and the result type are inconsistent");
2027 
2028   // check if we may construct a constant vector
2029   bool IsConst = true;
2030   for (unsigned i = I.getNumExplicitDefs();
2031        i < I.getNumExplicitOperands() && IsConst; ++i)
2032     if (!isConstReg(MRI, I.getOperand(i).getReg()))
2033       IsConst = false;
2034 
2035   if (!IsConst && N < 2)
2036     report_fatal_error(
2037         "There must be at least two constituent operands in a vector");
2038 
2039   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
2040                      TII.get(IsConst ? SPIRV::OpConstantComposite
2041                                      : SPIRV::OpCompositeConstruct))
2042                  .addDef(ResVReg)
2043                  .addUse(GR.getSPIRVTypeID(ResType));
2044   for (unsigned i = I.getNumExplicitDefs(); i < I.getNumExplicitOperands(); ++i)
2045     MIB.addUse(I.getOperand(i).getReg());
2046   return MIB.constrainAllUses(TII, TRI, RBI);
2047 }
2048 
2049 bool SPIRVInstructionSelector::selectSplatVector(Register ResVReg,
2050                                                  const SPIRVType *ResType,
2051                                                  MachineInstr &I) const {
2052   unsigned N = 0;
2053   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2054     N = GR.getScalarOrVectorComponentCount(ResType);
2055   else if (ResType->getOpcode() == SPIRV::OpTypeArray)
2056     N = getArrayComponentCount(MRI, ResType);
2057   else
2058     report_fatal_error("Cannot select G_SPLAT_VECTOR with a non-vector result");
2059 
2060   unsigned OpIdx = I.getNumExplicitDefs();
2061   if (!I.getOperand(OpIdx).isReg())
2062     report_fatal_error("Unexpected argument in G_SPLAT_VECTOR");
2063 
2064   // check if we may construct a constant vector
2065   Register OpReg = I.getOperand(OpIdx).getReg();
2066   bool IsConst = isConstReg(MRI, OpReg);
2067 
2068   if (!IsConst && N < 2)
2069     report_fatal_error(
2070         "There must be at least two constituent operands in a vector");
2071 
2072   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
2073                      TII.get(IsConst ? SPIRV::OpConstantComposite
2074                                      : SPIRV::OpCompositeConstruct))
2075                  .addDef(ResVReg)
2076                  .addUse(GR.getSPIRVTypeID(ResType));
2077   for (unsigned i = 0; i < N; ++i)
2078     MIB.addUse(OpReg);
2079   return MIB.constrainAllUses(TII, TRI, RBI);
2080 }
2081 
2082 bool SPIRVInstructionSelector::selectCmp(Register ResVReg,
2083                                          const SPIRVType *ResType,
2084                                          unsigned CmpOpc,
2085                                          MachineInstr &I) const {
2086   Register Cmp0 = I.getOperand(2).getReg();
2087   Register Cmp1 = I.getOperand(3).getReg();
2088   assert(GR.getSPIRVTypeForVReg(Cmp0)->getOpcode() ==
2089              GR.getSPIRVTypeForVReg(Cmp1)->getOpcode() &&
2090          "CMP operands should have the same type");
2091   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(CmpOpc))
2092       .addDef(ResVReg)
2093       .addUse(GR.getSPIRVTypeID(ResType))
2094       .addUse(Cmp0)
2095       .addUse(Cmp1)
2096       .constrainAllUses(TII, TRI, RBI);
2097 }
2098 
2099 bool SPIRVInstructionSelector::selectICmp(Register ResVReg,
2100                                           const SPIRVType *ResType,
2101                                           MachineInstr &I) const {
2102   auto Pred = I.getOperand(1).getPredicate();
2103   unsigned CmpOpc;
2104 
2105   Register CmpOperand = I.getOperand(2).getReg();
2106   if (GR.isScalarOfType(CmpOperand, SPIRV::OpTypePointer))
2107     CmpOpc = getPtrCmpOpcode(Pred);
2108   else if (GR.isScalarOrVectorOfType(CmpOperand, SPIRV::OpTypeBool))
2109     CmpOpc = getBoolCmpOpcode(Pred);
2110   else
2111     CmpOpc = getICmpOpcode(Pred);
2112   return selectCmp(ResVReg, ResType, CmpOpc, I);
2113 }
2114 
2115 void SPIRVInstructionSelector::renderFImm64(MachineInstrBuilder &MIB,
2116                                             const MachineInstr &I,
2117                                             int OpIdx) const {
2118   assert(I.getOpcode() == TargetOpcode::G_FCONSTANT && OpIdx == -1 &&
2119          "Expected G_FCONSTANT");
2120   const ConstantFP *FPImm = I.getOperand(1).getFPImm();
2121   addNumImm(FPImm->getValueAPF().bitcastToAPInt(), MIB);
2122 }
2123 
2124 void SPIRVInstructionSelector::renderImm32(MachineInstrBuilder &MIB,
2125                                            const MachineInstr &I,
2126                                            int OpIdx) const {
2127   assert(I.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
2128          "Expected G_CONSTANT");
2129   addNumImm(I.getOperand(1).getCImm()->getValue(), MIB);
2130 }
2131 
2132 Register
2133 SPIRVInstructionSelector::buildI32Constant(uint32_t Val, MachineInstr &I,
2134                                            const SPIRVType *ResType) const {
2135   Type *LLVMTy = IntegerType::get(GR.CurMF->getFunction().getContext(), 32);
2136   const SPIRVType *SpvI32Ty =
2137       ResType ? ResType : GR.getOrCreateSPIRVIntegerType(32, I, TII);
2138   // Find a constant in DT or build a new one.
2139   auto ConstInt = ConstantInt::get(LLVMTy, Val);
2140   Register NewReg = GR.find(ConstInt, GR.CurMF);
2141   if (!NewReg.isValid()) {
2142     NewReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
2143     GR.add(ConstInt, GR.CurMF, NewReg);
2144     MachineInstr *MI;
2145     MachineBasicBlock &BB = *I.getParent();
2146     if (Val == 0) {
2147       MI = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
2148                .addDef(NewReg)
2149                .addUse(GR.getSPIRVTypeID(SpvI32Ty));
2150     } else {
2151       MI = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantI))
2152                .addDef(NewReg)
2153                .addUse(GR.getSPIRVTypeID(SpvI32Ty))
2154                .addImm(APInt(32, Val).getZExtValue());
2155     }
2156     constrainSelectedInstRegOperands(*MI, TII, TRI, RBI);
2157   }
2158   return NewReg;
2159 }
2160 
2161 bool SPIRVInstructionSelector::selectFCmp(Register ResVReg,
2162                                           const SPIRVType *ResType,
2163                                           MachineInstr &I) const {
2164   unsigned CmpOp = getFCmpOpcode(I.getOperand(1).getPredicate());
2165   return selectCmp(ResVReg, ResType, CmpOp, I);
2166 }
2167 
2168 Register SPIRVInstructionSelector::buildZerosVal(const SPIRVType *ResType,
2169                                                  MachineInstr &I) const {
2170   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
2171   bool ZeroAsNull = STI.isOpenCLEnv();
2172   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2173     return GR.getOrCreateConstVector(0UL, I, ResType, TII, ZeroAsNull);
2174   return GR.getOrCreateConstInt(0, I, ResType, TII, ZeroAsNull);
2175 }
2176 
2177 Register SPIRVInstructionSelector::buildZerosValF(const SPIRVType *ResType,
2178                                                   MachineInstr &I) const {
2179   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
2180   bool ZeroAsNull = STI.isOpenCLEnv();
2181   APFloat VZero = getZeroFP(GR.getTypeForSPIRVType(ResType));
2182   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2183     return GR.getOrCreateConstVector(VZero, I, ResType, TII, ZeroAsNull);
2184   return GR.getOrCreateConstFP(VZero, I, ResType, TII, ZeroAsNull);
2185 }
2186 
2187 Register SPIRVInstructionSelector::buildOnesValF(const SPIRVType *ResType,
2188                                                  MachineInstr &I) const {
2189   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
2190   bool ZeroAsNull = STI.isOpenCLEnv();
2191   APFloat VOne = getOneFP(GR.getTypeForSPIRVType(ResType));
2192   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2193     return GR.getOrCreateConstVector(VOne, I, ResType, TII, ZeroAsNull);
2194   return GR.getOrCreateConstFP(VOne, I, ResType, TII, ZeroAsNull);
2195 }
2196 
2197 Register SPIRVInstructionSelector::buildOnesVal(bool AllOnes,
2198                                                 const SPIRVType *ResType,
2199                                                 MachineInstr &I) const {
2200   unsigned BitWidth = GR.getScalarOrVectorBitWidth(ResType);
2201   APInt One =
2202       AllOnes ? APInt::getAllOnes(BitWidth) : APInt::getOneBitSet(BitWidth, 0);
2203   if (ResType->getOpcode() == SPIRV::OpTypeVector)
2204     return GR.getOrCreateConstVector(One.getZExtValue(), I, ResType, TII);
2205   return GR.getOrCreateConstInt(One.getZExtValue(), I, ResType, TII);
2206 }
2207 
2208 bool SPIRVInstructionSelector::selectSelect(Register ResVReg,
2209                                             const SPIRVType *ResType,
2210                                             MachineInstr &I,
2211                                             bool IsSigned) const {
2212   // To extend a bool, we need to use OpSelect between constants.
2213   Register ZeroReg = buildZerosVal(ResType, I);
2214   Register OneReg = buildOnesVal(IsSigned, ResType, I);
2215   bool IsScalarBool =
2216       GR.isScalarOfType(I.getOperand(1).getReg(), SPIRV::OpTypeBool);
2217   unsigned Opcode =
2218       IsScalarBool ? SPIRV::OpSelectSISCond : SPIRV::OpSelectSIVCond;
2219   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
2220       .addDef(ResVReg)
2221       .addUse(GR.getSPIRVTypeID(ResType))
2222       .addUse(I.getOperand(1).getReg())
2223       .addUse(OneReg)
2224       .addUse(ZeroReg)
2225       .constrainAllUses(TII, TRI, RBI);
2226 }
2227 
2228 bool SPIRVInstructionSelector::selectIToF(Register ResVReg,
2229                                           const SPIRVType *ResType,
2230                                           MachineInstr &I, bool IsSigned,
2231                                           unsigned Opcode) const {
2232   Register SrcReg = I.getOperand(1).getReg();
2233   // We can convert bool value directly to float type without OpConvert*ToF,
2234   // however the translator generates OpSelect+OpConvert*ToF, so we do the same.
2235   if (GR.isScalarOrVectorOfType(I.getOperand(1).getReg(), SPIRV::OpTypeBool)) {
2236     unsigned BitWidth = GR.getScalarOrVectorBitWidth(ResType);
2237     SPIRVType *TmpType = GR.getOrCreateSPIRVIntegerType(BitWidth, I, TII);
2238     if (ResType->getOpcode() == SPIRV::OpTypeVector) {
2239       const unsigned NumElts = ResType->getOperand(2).getImm();
2240       TmpType = GR.getOrCreateSPIRVVectorType(TmpType, NumElts, I, TII);
2241     }
2242     SrcReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2243     selectSelect(SrcReg, TmpType, I, false);
2244   }
2245   return selectUnOpWithSrc(ResVReg, ResType, I, SrcReg, Opcode);
2246 }
2247 
2248 bool SPIRVInstructionSelector::selectExt(Register ResVReg,
2249                                          const SPIRVType *ResType,
2250                                          MachineInstr &I, bool IsSigned) const {
2251   Register SrcReg = I.getOperand(1).getReg();
2252   if (GR.isScalarOrVectorOfType(SrcReg, SPIRV::OpTypeBool))
2253     return selectSelect(ResVReg, ResType, I, IsSigned);
2254 
2255   SPIRVType *SrcType = GR.getSPIRVTypeForVReg(SrcReg);
2256   if (SrcType == ResType) {
2257     const TargetRegisterClass *DstRC = MRI->getRegClassOrNull(ResVReg);
2258     const TargetRegisterClass *SrcRC = MRI->getRegClassOrNull(SrcReg);
2259     if (DstRC != SrcRC && SrcRC)
2260       MRI->setRegClass(ResVReg, SrcRC);
2261     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
2262                    TII.get(TargetOpcode::COPY))
2263         .addDef(ResVReg)
2264         .addUse(SrcReg)
2265         .constrainAllUses(TII, TRI, RBI);
2266   }
2267 
2268   unsigned Opcode = IsSigned ? SPIRV::OpSConvert : SPIRV::OpUConvert;
2269   return selectUnOp(ResVReg, ResType, I, Opcode);
2270 }
2271 
2272 bool SPIRVInstructionSelector::selectIntToBool(Register IntReg,
2273                                                Register ResVReg,
2274                                                MachineInstr &I,
2275                                                const SPIRVType *IntTy,
2276                                                const SPIRVType *BoolTy) const {
2277   // To truncate to a bool, we use OpBitwiseAnd 1 and OpINotEqual to zero.
2278   Register BitIntReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2279   bool IsVectorTy = IntTy->getOpcode() == SPIRV::OpTypeVector;
2280   unsigned Opcode = IsVectorTy ? SPIRV::OpBitwiseAndV : SPIRV::OpBitwiseAndS;
2281   Register Zero = buildZerosVal(IntTy, I);
2282   Register One = buildOnesVal(false, IntTy, I);
2283   MachineBasicBlock &BB = *I.getParent();
2284   BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2285       .addDef(BitIntReg)
2286       .addUse(GR.getSPIRVTypeID(IntTy))
2287       .addUse(IntReg)
2288       .addUse(One)
2289       .constrainAllUses(TII, TRI, RBI);
2290   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpINotEqual))
2291       .addDef(ResVReg)
2292       .addUse(GR.getSPIRVTypeID(BoolTy))
2293       .addUse(BitIntReg)
2294       .addUse(Zero)
2295       .constrainAllUses(TII, TRI, RBI);
2296 }
2297 
2298 bool SPIRVInstructionSelector::selectTrunc(Register ResVReg,
2299                                            const SPIRVType *ResType,
2300                                            MachineInstr &I) const {
2301   Register IntReg = I.getOperand(1).getReg();
2302   const SPIRVType *ArgType = GR.getSPIRVTypeForVReg(IntReg);
2303   if (GR.isScalarOrVectorOfType(ResVReg, SPIRV::OpTypeBool))
2304     return selectIntToBool(IntReg, ResVReg, I, ArgType, ResType);
2305   if (ArgType == ResType) {
2306     const TargetRegisterClass *DstRC = MRI->getRegClassOrNull(ResVReg);
2307     const TargetRegisterClass *SrcRC = MRI->getRegClassOrNull(IntReg);
2308     if (DstRC != SrcRC && SrcRC)
2309       MRI->setRegClass(ResVReg, SrcRC);
2310     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
2311                    TII.get(TargetOpcode::COPY))
2312         .addDef(ResVReg)
2313         .addUse(IntReg)
2314         .constrainAllUses(TII, TRI, RBI);
2315   }
2316   bool IsSigned = GR.isScalarOrVectorSigned(ResType);
2317   unsigned Opcode = IsSigned ? SPIRV::OpSConvert : SPIRV::OpUConvert;
2318   return selectUnOp(ResVReg, ResType, I, Opcode);
2319 }
2320 
2321 bool SPIRVInstructionSelector::selectConst(Register ResVReg,
2322                                            const SPIRVType *ResType,
2323                                            const APInt &Imm,
2324                                            MachineInstr &I) const {
2325   unsigned TyOpcode = ResType->getOpcode();
2326   assert(TyOpcode != SPIRV::OpTypePointer || Imm.isZero());
2327   MachineBasicBlock &BB = *I.getParent();
2328   if ((TyOpcode == SPIRV::OpTypePointer || TyOpcode == SPIRV::OpTypeEvent) &&
2329       Imm.isZero())
2330     return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
2331         .addDef(ResVReg)
2332         .addUse(GR.getSPIRVTypeID(ResType))
2333         .constrainAllUses(TII, TRI, RBI);
2334   if (TyOpcode == SPIRV::OpTypeInt) {
2335     assert(Imm.getBitWidth() <= 64 && "Unsupported integer width!");
2336     Register Reg = GR.getOrCreateConstInt(Imm.getZExtValue(), I, ResType, TII);
2337     if (Reg == ResVReg)
2338       return true;
2339     return BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY))
2340         .addDef(ResVReg)
2341         .addUse(Reg)
2342         .constrainAllUses(TII, TRI, RBI);
2343   }
2344   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantI))
2345                  .addDef(ResVReg)
2346                  .addUse(GR.getSPIRVTypeID(ResType));
2347   // <=32-bit integers should be caught by the sdag pattern.
2348   assert(Imm.getBitWidth() > 32);
2349   addNumImm(Imm, MIB);
2350   return MIB.constrainAllUses(TII, TRI, RBI);
2351 }
2352 
2353 bool SPIRVInstructionSelector::selectOpUndef(Register ResVReg,
2354                                              const SPIRVType *ResType,
2355                                              MachineInstr &I) const {
2356   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpUndef))
2357       .addDef(ResVReg)
2358       .addUse(GR.getSPIRVTypeID(ResType))
2359       .constrainAllUses(TII, TRI, RBI);
2360 }
2361 
2362 static bool isImm(const MachineOperand &MO, MachineRegisterInfo *MRI) {
2363   assert(MO.isReg());
2364   const SPIRVType *TypeInst = MRI->getVRegDef(MO.getReg());
2365   if (TypeInst->getOpcode() == SPIRV::ASSIGN_TYPE) {
2366     assert(TypeInst->getOperand(1).isReg());
2367     MachineInstr *ImmInst = MRI->getVRegDef(TypeInst->getOperand(1).getReg());
2368     return ImmInst->getOpcode() == TargetOpcode::G_CONSTANT;
2369   }
2370   return TypeInst->getOpcode() == SPIRV::OpConstantI;
2371 }
2372 
2373 static int64_t foldImm(const MachineOperand &MO, MachineRegisterInfo *MRI) {
2374   const SPIRVType *TypeInst = MRI->getVRegDef(MO.getReg());
2375   if (TypeInst->getOpcode() == SPIRV::OpConstantI)
2376     return TypeInst->getOperand(2).getImm();
2377   MachineInstr *ImmInst = MRI->getVRegDef(TypeInst->getOperand(1).getReg());
2378   assert(ImmInst->getOpcode() == TargetOpcode::G_CONSTANT);
2379   return ImmInst->getOperand(1).getCImm()->getZExtValue();
2380 }
2381 
2382 bool SPIRVInstructionSelector::selectInsertVal(Register ResVReg,
2383                                                const SPIRVType *ResType,
2384                                                MachineInstr &I) const {
2385   MachineBasicBlock &BB = *I.getParent();
2386   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeInsert))
2387                  .addDef(ResVReg)
2388                  .addUse(GR.getSPIRVTypeID(ResType))
2389                  // object to insert
2390                  .addUse(I.getOperand(3).getReg())
2391                  // composite to insert into
2392                  .addUse(I.getOperand(2).getReg());
2393   for (unsigned i = 4; i < I.getNumOperands(); i++)
2394     MIB.addImm(foldImm(I.getOperand(i), MRI));
2395   return MIB.constrainAllUses(TII, TRI, RBI);
2396 }
2397 
2398 bool SPIRVInstructionSelector::selectExtractVal(Register ResVReg,
2399                                                 const SPIRVType *ResType,
2400                                                 MachineInstr &I) const {
2401   MachineBasicBlock &BB = *I.getParent();
2402   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
2403                  .addDef(ResVReg)
2404                  .addUse(GR.getSPIRVTypeID(ResType))
2405                  .addUse(I.getOperand(2).getReg());
2406   for (unsigned i = 3; i < I.getNumOperands(); i++)
2407     MIB.addImm(foldImm(I.getOperand(i), MRI));
2408   return MIB.constrainAllUses(TII, TRI, RBI);
2409 }
2410 
2411 bool SPIRVInstructionSelector::selectInsertElt(Register ResVReg,
2412                                                const SPIRVType *ResType,
2413                                                MachineInstr &I) const {
2414   if (isImm(I.getOperand(4), MRI))
2415     return selectInsertVal(ResVReg, ResType, I);
2416   MachineBasicBlock &BB = *I.getParent();
2417   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorInsertDynamic))
2418       .addDef(ResVReg)
2419       .addUse(GR.getSPIRVTypeID(ResType))
2420       .addUse(I.getOperand(2).getReg())
2421       .addUse(I.getOperand(3).getReg())
2422       .addUse(I.getOperand(4).getReg())
2423       .constrainAllUses(TII, TRI, RBI);
2424 }
2425 
2426 bool SPIRVInstructionSelector::selectExtractElt(Register ResVReg,
2427                                                 const SPIRVType *ResType,
2428                                                 MachineInstr &I) const {
2429   if (isImm(I.getOperand(3), MRI))
2430     return selectExtractVal(ResVReg, ResType, I);
2431   MachineBasicBlock &BB = *I.getParent();
2432   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorExtractDynamic))
2433       .addDef(ResVReg)
2434       .addUse(GR.getSPIRVTypeID(ResType))
2435       .addUse(I.getOperand(2).getReg())
2436       .addUse(I.getOperand(3).getReg())
2437       .constrainAllUses(TII, TRI, RBI);
2438 }
2439 
2440 bool SPIRVInstructionSelector::selectGEP(Register ResVReg,
2441                                          const SPIRVType *ResType,
2442                                          MachineInstr &I) const {
2443   const bool IsGEPInBounds = I.getOperand(2).getImm();
2444 
2445   // OpAccessChain could be used for OpenCL, but the SPIRV-LLVM Translator only
2446   // relies on PtrAccessChain, so we'll try not to deviate. For Vulkan however,
2447   // we have to use Op[InBounds]AccessChain.
2448   const unsigned Opcode = STI.isVulkanEnv()
2449                               ? (IsGEPInBounds ? SPIRV::OpInBoundsAccessChain
2450                                                : SPIRV::OpAccessChain)
2451                               : (IsGEPInBounds ? SPIRV::OpInBoundsPtrAccessChain
2452                                                : SPIRV::OpPtrAccessChain);
2453 
2454   auto Res = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
2455                  .addDef(ResVReg)
2456                  .addUse(GR.getSPIRVTypeID(ResType))
2457                  // Object to get a pointer to.
2458                  .addUse(I.getOperand(3).getReg());
2459   // Adding indices.
2460   const unsigned StartingIndex =
2461       (Opcode == SPIRV::OpAccessChain || Opcode == SPIRV::OpInBoundsAccessChain)
2462           ? 5
2463           : 4;
2464   for (unsigned i = StartingIndex; i < I.getNumExplicitOperands(); ++i)
2465     Res.addUse(I.getOperand(i).getReg());
2466   return Res.constrainAllUses(TII, TRI, RBI);
2467 }
2468 
2469 // Maybe wrap a value into OpSpecConstantOp
2470 bool SPIRVInstructionSelector::wrapIntoSpecConstantOp(
2471     MachineInstr &I, SmallVector<Register> &CompositeArgs) const {
2472   bool Result = true;
2473   unsigned Lim = I.getNumExplicitOperands();
2474   for (unsigned i = I.getNumExplicitDefs() + 1; i < Lim; ++i) {
2475     Register OpReg = I.getOperand(i).getReg();
2476     SPIRVType *OpDefine = MRI->getVRegDef(OpReg);
2477     SPIRVType *OpType = GR.getSPIRVTypeForVReg(OpReg);
2478     SmallPtrSet<SPIRVType *, 4> Visited;
2479     if (!OpDefine || !OpType || isConstReg(MRI, OpDefine, Visited) ||
2480         OpDefine->getOpcode() == TargetOpcode::G_ADDRSPACE_CAST ||
2481         GR.isAggregateType(OpType)) {
2482       // The case of G_ADDRSPACE_CAST inside spv_const_composite() is processed
2483       // by selectAddrSpaceCast()
2484       CompositeArgs.push_back(OpReg);
2485       continue;
2486     }
2487     MachineFunction *MF = I.getMF();
2488     Register WrapReg = GR.find(OpDefine, MF);
2489     if (WrapReg.isValid()) {
2490       CompositeArgs.push_back(WrapReg);
2491       continue;
2492     }
2493     // Create a new register for the wrapper
2494     WrapReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2495     GR.add(OpDefine, MF, WrapReg);
2496     CompositeArgs.push_back(WrapReg);
2497     // Decorate the wrapper register and generate a new instruction
2498     MRI->setType(WrapReg, LLT::pointer(0, 64));
2499     GR.assignSPIRVTypeToVReg(OpType, WrapReg, *MF);
2500     MachineBasicBlock &BB = *I.getParent();
2501     Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
2502                  .addDef(WrapReg)
2503                  .addUse(GR.getSPIRVTypeID(OpType))
2504                  .addImm(static_cast<uint32_t>(SPIRV::Opcode::Bitcast))
2505                  .addUse(OpReg)
2506                  .constrainAllUses(TII, TRI, RBI);
2507     if (!Result)
2508       break;
2509   }
2510   return Result;
2511 }
2512 
2513 bool SPIRVInstructionSelector::selectIntrinsic(Register ResVReg,
2514                                                const SPIRVType *ResType,
2515                                                MachineInstr &I) const {
2516   MachineBasicBlock &BB = *I.getParent();
2517   Intrinsic::ID IID = cast<GIntrinsic>(I).getIntrinsicID();
2518   switch (IID) {
2519   case Intrinsic::spv_load:
2520     return selectLoad(ResVReg, ResType, I);
2521   case Intrinsic::spv_store:
2522     return selectStore(I);
2523   case Intrinsic::spv_extractv:
2524     return selectExtractVal(ResVReg, ResType, I);
2525   case Intrinsic::spv_insertv:
2526     return selectInsertVal(ResVReg, ResType, I);
2527   case Intrinsic::spv_extractelt:
2528     return selectExtractElt(ResVReg, ResType, I);
2529   case Intrinsic::spv_insertelt:
2530     return selectInsertElt(ResVReg, ResType, I);
2531   case Intrinsic::spv_gep:
2532     return selectGEP(ResVReg, ResType, I);
2533   case Intrinsic::spv_unref_global:
2534   case Intrinsic::spv_init_global: {
2535     MachineInstr *MI = MRI->getVRegDef(I.getOperand(1).getReg());
2536     MachineInstr *Init = I.getNumExplicitOperands() > 2
2537                              ? MRI->getVRegDef(I.getOperand(2).getReg())
2538                              : nullptr;
2539     assert(MI);
2540     return selectGlobalValue(MI->getOperand(0).getReg(), *MI, Init);
2541   }
2542   case Intrinsic::spv_undef: {
2543     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpUndef))
2544                    .addDef(ResVReg)
2545                    .addUse(GR.getSPIRVTypeID(ResType));
2546     return MIB.constrainAllUses(TII, TRI, RBI);
2547   }
2548   case Intrinsic::spv_const_composite: {
2549     // If no values are attached, the composite is null constant.
2550     bool IsNull = I.getNumExplicitDefs() + 1 == I.getNumExplicitOperands();
2551     // Select a proper instruction.
2552     unsigned Opcode = SPIRV::OpConstantNull;
2553     SmallVector<Register> CompositeArgs;
2554     if (!IsNull) {
2555       Opcode = SPIRV::OpConstantComposite;
2556       if (!wrapIntoSpecConstantOp(I, CompositeArgs))
2557         return false;
2558     }
2559     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2560                    .addDef(ResVReg)
2561                    .addUse(GR.getSPIRVTypeID(ResType));
2562     // skip type MD node we already used when generated assign.type for this
2563     if (!IsNull) {
2564       for (Register OpReg : CompositeArgs)
2565         MIB.addUse(OpReg);
2566     }
2567     return MIB.constrainAllUses(TII, TRI, RBI);
2568   }
2569   case Intrinsic::spv_assign_name: {
2570     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpName));
2571     MIB.addUse(I.getOperand(I.getNumExplicitDefs() + 1).getReg());
2572     for (unsigned i = I.getNumExplicitDefs() + 2;
2573          i < I.getNumExplicitOperands(); ++i) {
2574       MIB.addImm(I.getOperand(i).getImm());
2575     }
2576     return MIB.constrainAllUses(TII, TRI, RBI);
2577   }
2578   case Intrinsic::spv_switch: {
2579     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSwitch));
2580     for (unsigned i = 1; i < I.getNumExplicitOperands(); ++i) {
2581       if (I.getOperand(i).isReg())
2582         MIB.addReg(I.getOperand(i).getReg());
2583       else if (I.getOperand(i).isCImm())
2584         addNumImm(I.getOperand(i).getCImm()->getValue(), MIB);
2585       else if (I.getOperand(i).isMBB())
2586         MIB.addMBB(I.getOperand(i).getMBB());
2587       else
2588         llvm_unreachable("Unexpected OpSwitch operand");
2589     }
2590     return MIB.constrainAllUses(TII, TRI, RBI);
2591   }
2592   case Intrinsic::spv_loop_merge:
2593   case Intrinsic::spv_selection_merge: {
2594     const auto Opcode = IID == Intrinsic::spv_selection_merge
2595                             ? SPIRV::OpSelectionMerge
2596                             : SPIRV::OpLoopMerge;
2597     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode));
2598     for (unsigned i = 1; i < I.getNumExplicitOperands(); ++i) {
2599       assert(I.getOperand(i).isMBB());
2600       MIB.addMBB(I.getOperand(i).getMBB());
2601     }
2602     MIB.addImm(SPIRV::SelectionControl::None);
2603     return MIB.constrainAllUses(TII, TRI, RBI);
2604   }
2605   case Intrinsic::spv_cmpxchg:
2606     return selectAtomicCmpXchg(ResVReg, ResType, I);
2607   case Intrinsic::spv_unreachable:
2608     BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpUnreachable));
2609     break;
2610   case Intrinsic::spv_alloca:
2611     return selectFrameIndex(ResVReg, ResType, I);
2612   case Intrinsic::spv_alloca_array:
2613     return selectAllocaArray(ResVReg, ResType, I);
2614   case Intrinsic::spv_assume:
2615     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_expect_assume))
2616       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpAssumeTrueKHR))
2617           .addUse(I.getOperand(1).getReg());
2618     break;
2619   case Intrinsic::spv_expect:
2620     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_expect_assume))
2621       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExpectKHR))
2622           .addDef(ResVReg)
2623           .addUse(GR.getSPIRVTypeID(ResType))
2624           .addUse(I.getOperand(2).getReg())
2625           .addUse(I.getOperand(3).getReg());
2626     break;
2627   case Intrinsic::arithmetic_fence:
2628     if (STI.canUseExtension(SPIRV::Extension::SPV_EXT_arithmetic_fence))
2629       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpArithmeticFenceEXT))
2630           .addDef(ResVReg)
2631           .addUse(GR.getSPIRVTypeID(ResType))
2632           .addUse(I.getOperand(2).getReg());
2633     else
2634       BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY), ResVReg)
2635           .addUse(I.getOperand(2).getReg());
2636     break;
2637   case Intrinsic::spv_thread_id:
2638     return selectSpvThreadId(ResVReg, ResType, I);
2639   case Intrinsic::spv_fdot:
2640     return selectFloatDot(ResVReg, ResType, I);
2641   case Intrinsic::spv_udot:
2642   case Intrinsic::spv_sdot:
2643     return selectIntegerDot(ResVReg, ResType, I);
2644   case Intrinsic::spv_dot4add_i8packed:
2645     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_integer_dot_product) ||
2646         STI.isAtLeastSPIRVVer(VersionTuple(1, 6)))
2647       return selectDot4AddPacked<true>(ResVReg, ResType, I);
2648     return selectDot4AddPackedExpansion<true>(ResVReg, ResType, I);
2649   case Intrinsic::spv_all:
2650     return selectAll(ResVReg, ResType, I);
2651   case Intrinsic::spv_any:
2652     return selectAny(ResVReg, ResType, I);
2653   case Intrinsic::spv_cross:
2654     return selectExtInst(ResVReg, ResType, I, CL::cross, GL::Cross);
2655   case Intrinsic::spv_lerp:
2656     return selectExtInst(ResVReg, ResType, I, CL::mix, GL::FMix);
2657   case Intrinsic::spv_length:
2658     return selectExtInst(ResVReg, ResType, I, CL::length, GL::Length);
2659   case Intrinsic::spv_degrees:
2660     return selectExtInst(ResVReg, ResType, I, CL::degrees, GL::Degrees);
2661   case Intrinsic::spv_frac:
2662     return selectExtInst(ResVReg, ResType, I, CL::fract, GL::Fract);
2663   case Intrinsic::spv_normalize:
2664     return selectExtInst(ResVReg, ResType, I, CL::normalize, GL::Normalize);
2665   case Intrinsic::spv_rsqrt:
2666     return selectExtInst(ResVReg, ResType, I, CL::rsqrt, GL::InverseSqrt);
2667   case Intrinsic::spv_sign:
2668     return selectSign(ResVReg, ResType, I);
2669   case Intrinsic::spv_group_memory_barrier_with_group_sync: {
2670     Register MemSemReg =
2671         buildI32Constant(SPIRV::MemorySemantics::SequentiallyConsistent, I);
2672     Register ScopeReg = buildI32Constant(SPIRV::Scope::Workgroup, I);
2673     MachineBasicBlock &BB = *I.getParent();
2674     return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpControlBarrier))
2675         .addUse(ScopeReg)
2676         .addUse(ScopeReg)
2677         .addUse(MemSemReg)
2678         .constrainAllUses(TII, TRI, RBI);
2679   } break;
2680   case Intrinsic::spv_lifetime_start:
2681   case Intrinsic::spv_lifetime_end: {
2682     unsigned Op = IID == Intrinsic::spv_lifetime_start ? SPIRV::OpLifetimeStart
2683                                                        : SPIRV::OpLifetimeStop;
2684     int64_t Size = I.getOperand(I.getNumExplicitDefs() + 1).getImm();
2685     Register PtrReg = I.getOperand(I.getNumExplicitDefs() + 2).getReg();
2686     if (Size == -1)
2687       Size = 0;
2688     BuildMI(BB, I, I.getDebugLoc(), TII.get(Op)).addUse(PtrReg).addImm(Size);
2689   } break;
2690   case Intrinsic::spv_saturate:
2691     return selectSaturate(ResVReg, ResType, I);
2692   case Intrinsic::spv_wave_is_first_lane: {
2693     SPIRVType *IntTy = GR.getOrCreateSPIRVIntegerType(32, I, TII);
2694     return BuildMI(BB, I, I.getDebugLoc(),
2695                    TII.get(SPIRV::OpGroupNonUniformElect))
2696         .addDef(ResVReg)
2697         .addUse(GR.getSPIRVTypeID(ResType))
2698         .addUse(GR.getOrCreateConstInt(3, I, IntTy, TII));
2699   }
2700   case Intrinsic::spv_wave_readlane:
2701     return selectWaveReadLaneAt(ResVReg, ResType, I);
2702   case Intrinsic::spv_step:
2703     return selectExtInst(ResVReg, ResType, I, CL::step, GL::Step);
2704   case Intrinsic::spv_radians:
2705     return selectExtInst(ResVReg, ResType, I, CL::radians, GL::Radians);
2706   // Discard intrinsics which we do not expect to actually represent code after
2707   // lowering or intrinsics which are not implemented but should not crash when
2708   // found in a customer's LLVM IR input.
2709   case Intrinsic::instrprof_increment:
2710   case Intrinsic::instrprof_increment_step:
2711   case Intrinsic::instrprof_value_profile:
2712     break;
2713   // Discard internal intrinsics.
2714   case Intrinsic::spv_value_md:
2715     break;
2716   case Intrinsic::spv_handle_fromBinding: {
2717     selectHandleFromBinding(ResVReg, ResType, I);
2718     return true;
2719   }
2720   default: {
2721     std::string DiagMsg;
2722     raw_string_ostream OS(DiagMsg);
2723     I.print(OS);
2724     DiagMsg = "Intrinsic selection not implemented: " + DiagMsg;
2725     report_fatal_error(DiagMsg.c_str(), false);
2726   }
2727   }
2728   return true;
2729 }
2730 
2731 void SPIRVInstructionSelector::selectHandleFromBinding(Register &ResVReg,
2732                                                        const SPIRVType *ResType,
2733                                                        MachineInstr &I) const {
2734 
2735   uint32_t Set = foldImm(I.getOperand(2), MRI);
2736   uint32_t Binding = foldImm(I.getOperand(3), MRI);
2737   uint32_t ArraySize = foldImm(I.getOperand(4), MRI);
2738   Register IndexReg = I.getOperand(5).getReg();
2739   bool IsNonUniform = ArraySize > 1 && foldImm(I.getOperand(6), MRI);
2740 
2741   MachineIRBuilder MIRBuilder(I);
2742   Register VarReg = buildPointerToResource(ResType, Set, Binding, ArraySize,
2743                                            IndexReg, IsNonUniform, MIRBuilder);
2744 
2745   if (IsNonUniform)
2746     buildOpDecorate(ResVReg, I, TII, SPIRV::Decoration::NonUniformEXT, {});
2747 
2748   // TODO: For now we assume the resource is an image, which needs to be
2749   // loaded to get the handle. That will not be true for storage buffers.
2750   BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
2751       .addDef(ResVReg)
2752       .addUse(GR.getSPIRVTypeID(ResType))
2753       .addUse(VarReg);
2754 }
2755 
2756 Register SPIRVInstructionSelector::buildPointerToResource(
2757     const SPIRVType *ResType, uint32_t Set, uint32_t Binding,
2758     uint32_t ArraySize, Register IndexReg, bool IsNonUniform,
2759     MachineIRBuilder MIRBuilder) const {
2760   if (ArraySize == 1)
2761     return GR.getOrCreateGlobalVariableWithBinding(ResType, Set, Binding,
2762                                                    MIRBuilder);
2763 
2764   const SPIRVType *VarType = GR.getOrCreateSPIRVArrayType(
2765       ResType, ArraySize, *MIRBuilder.getInsertPt(), TII);
2766   Register VarReg = GR.getOrCreateGlobalVariableWithBinding(
2767       VarType, Set, Binding, MIRBuilder);
2768 
2769   SPIRVType *ResPointerType = GR.getOrCreateSPIRVPointerType(
2770       ResType, MIRBuilder, SPIRV::StorageClass::UniformConstant);
2771 
2772   Register AcReg = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
2773   if (IsNonUniform) {
2774     // It is unclear which value needs to be marked an non-uniform, so both
2775     // the index and the access changed are decorated as non-uniform.
2776     buildOpDecorate(IndexReg, MIRBuilder, SPIRV::Decoration::NonUniformEXT, {});
2777     buildOpDecorate(AcReg, MIRBuilder, SPIRV::Decoration::NonUniformEXT, {});
2778   }
2779 
2780   MIRBuilder.buildInstr(SPIRV::OpAccessChain)
2781       .addDef(AcReg)
2782       .addUse(GR.getSPIRVTypeID(ResPointerType))
2783       .addUse(VarReg)
2784       .addUse(IndexReg);
2785 
2786   return AcReg;
2787 }
2788 
2789 bool SPIRVInstructionSelector::selectAllocaArray(Register ResVReg,
2790                                                  const SPIRVType *ResType,
2791                                                  MachineInstr &I) const {
2792   // there was an allocation size parameter to the allocation instruction
2793   // that is not 1
2794   MachineBasicBlock &BB = *I.getParent();
2795   return BuildMI(BB, I, I.getDebugLoc(),
2796                  TII.get(SPIRV::OpVariableLengthArrayINTEL))
2797       .addDef(ResVReg)
2798       .addUse(GR.getSPIRVTypeID(ResType))
2799       .addUse(I.getOperand(2).getReg())
2800       .constrainAllUses(TII, TRI, RBI);
2801 }
2802 
2803 bool SPIRVInstructionSelector::selectFrameIndex(Register ResVReg,
2804                                                 const SPIRVType *ResType,
2805                                                 MachineInstr &I) const {
2806   // Change order of instructions if needed: all OpVariable instructions in a
2807   // function must be the first instructions in the first block
2808   MachineFunction *MF = I.getParent()->getParent();
2809   MachineBasicBlock *MBB = &MF->front();
2810   auto It = MBB->SkipPHIsAndLabels(MBB->begin()), E = MBB->end();
2811   bool IsHeader = false;
2812   unsigned Opcode;
2813   for (; It != E && It != I; ++It) {
2814     Opcode = It->getOpcode();
2815     if (Opcode == SPIRV::OpFunction || Opcode == SPIRV::OpFunctionParameter) {
2816       IsHeader = true;
2817     } else if (IsHeader &&
2818                !(Opcode == SPIRV::ASSIGN_TYPE || Opcode == SPIRV::OpLabel)) {
2819       ++It;
2820       break;
2821     }
2822   }
2823   return BuildMI(*MBB, It, It->getDebugLoc(), TII.get(SPIRV::OpVariable))
2824       .addDef(ResVReg)
2825       .addUse(GR.getSPIRVTypeID(ResType))
2826       .addImm(static_cast<uint32_t>(SPIRV::StorageClass::Function))
2827       .constrainAllUses(TII, TRI, RBI);
2828 }
2829 
2830 bool SPIRVInstructionSelector::selectBranch(MachineInstr &I) const {
2831   // InstructionSelector walks backwards through the instructions. We can use
2832   // both a G_BR and a G_BRCOND to create an OpBranchConditional. We hit G_BR
2833   // first, so can generate an OpBranchConditional here. If there is no
2834   // G_BRCOND, we just use OpBranch for a regular unconditional branch.
2835   const MachineInstr *PrevI = I.getPrevNode();
2836   MachineBasicBlock &MBB = *I.getParent();
2837   if (PrevI != nullptr && PrevI->getOpcode() == TargetOpcode::G_BRCOND) {
2838     return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranchConditional))
2839         .addUse(PrevI->getOperand(0).getReg())
2840         .addMBB(PrevI->getOperand(1).getMBB())
2841         .addMBB(I.getOperand(0).getMBB())
2842         .constrainAllUses(TII, TRI, RBI);
2843   }
2844   return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranch))
2845       .addMBB(I.getOperand(0).getMBB())
2846       .constrainAllUses(TII, TRI, RBI);
2847 }
2848 
2849 bool SPIRVInstructionSelector::selectBranchCond(MachineInstr &I) const {
2850   // InstructionSelector walks backwards through the instructions. For an
2851   // explicit conditional branch with no fallthrough, we use both a G_BR and a
2852   // G_BRCOND to create an OpBranchConditional. We should hit G_BR first, and
2853   // generate the OpBranchConditional in selectBranch above.
2854   //
2855   // If an OpBranchConditional has been generated, we simply return, as the work
2856   // is alread done. If there is no OpBranchConditional, LLVM must be relying on
2857   // implicit fallthrough to the next basic block, so we need to create an
2858   // OpBranchConditional with an explicit "false" argument pointing to the next
2859   // basic block that LLVM would fall through to.
2860   const MachineInstr *NextI = I.getNextNode();
2861   // Check if this has already been successfully selected.
2862   if (NextI != nullptr && NextI->getOpcode() == SPIRV::OpBranchConditional)
2863     return true;
2864   // Must be relying on implicit block fallthrough, so generate an
2865   // OpBranchConditional with the "next" basic block as the "false" target.
2866   MachineBasicBlock &MBB = *I.getParent();
2867   unsigned NextMBBNum = MBB.getNextNode()->getNumber();
2868   MachineBasicBlock *NextMBB = I.getMF()->getBlockNumbered(NextMBBNum);
2869   return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranchConditional))
2870       .addUse(I.getOperand(0).getReg())
2871       .addMBB(I.getOperand(1).getMBB())
2872       .addMBB(NextMBB)
2873       .constrainAllUses(TII, TRI, RBI);
2874 }
2875 
2876 bool SPIRVInstructionSelector::selectPhi(Register ResVReg,
2877                                          const SPIRVType *ResType,
2878                                          MachineInstr &I) const {
2879   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpPhi))
2880                  .addDef(ResVReg)
2881                  .addUse(GR.getSPIRVTypeID(ResType));
2882   const unsigned NumOps = I.getNumOperands();
2883   for (unsigned i = 1; i < NumOps; i += 2) {
2884     MIB.addUse(I.getOperand(i + 0).getReg());
2885     MIB.addMBB(I.getOperand(i + 1).getMBB());
2886   }
2887   return MIB.constrainAllUses(TII, TRI, RBI);
2888 }
2889 
2890 bool SPIRVInstructionSelector::selectGlobalValue(
2891     Register ResVReg, MachineInstr &I, const MachineInstr *Init) const {
2892   // FIXME: don't use MachineIRBuilder here, replace it with BuildMI.
2893   MachineIRBuilder MIRBuilder(I);
2894   const GlobalValue *GV = I.getOperand(1).getGlobal();
2895   Type *GVType = toTypedPointer(GR.getDeducedGlobalValueType(GV));
2896   SPIRVType *PointerBaseType;
2897   if (GVType->isArrayTy()) {
2898     SPIRVType *ArrayElementType =
2899         GR.getOrCreateSPIRVType(GVType->getArrayElementType(), MIRBuilder,
2900                                 SPIRV::AccessQualifier::ReadWrite, false);
2901     PointerBaseType = GR.getOrCreateSPIRVArrayType(
2902         ArrayElementType, GVType->getArrayNumElements(), I, TII);
2903   } else {
2904     PointerBaseType = GR.getOrCreateSPIRVType(
2905         GVType, MIRBuilder, SPIRV::AccessQualifier::ReadWrite, false);
2906   }
2907   SPIRVType *ResType = GR.getOrCreateSPIRVPointerType(
2908       PointerBaseType, I, TII,
2909       addressSpaceToStorageClass(GV->getAddressSpace(), STI));
2910 
2911   std::string GlobalIdent;
2912   if (!GV->hasName()) {
2913     unsigned &ID = UnnamedGlobalIDs[GV];
2914     if (ID == 0)
2915       ID = UnnamedGlobalIDs.size();
2916     GlobalIdent = "__unnamed_" + Twine(ID).str();
2917   } else {
2918     GlobalIdent = GV->getGlobalIdentifier();
2919   }
2920 
2921   // Behaviour of functions as operands depends on availability of the
2922   // corresponding extension (SPV_INTEL_function_pointers):
2923   // - If there is an extension to operate with functions as operands:
2924   // We create a proper constant operand and evaluate a correct type for a
2925   // function pointer.
2926   // - Without the required extension:
2927   // We have functions as operands in tests with blocks of instruction e.g. in
2928   // transcoding/global_block.ll. These operands are not used and should be
2929   // substituted by zero constants. Their type is expected to be always
2930   // OpTypePointer Function %uchar.
2931   if (isa<Function>(GV)) {
2932     const Constant *ConstVal = GV;
2933     MachineBasicBlock &BB = *I.getParent();
2934     Register NewReg = GR.find(ConstVal, GR.CurMF);
2935     if (!NewReg.isValid()) {
2936       Register NewReg = ResVReg;
2937       GR.add(ConstVal, GR.CurMF, NewReg);
2938       const Function *GVFun =
2939           STI.canUseExtension(SPIRV::Extension::SPV_INTEL_function_pointers)
2940               ? dyn_cast<Function>(GV)
2941               : nullptr;
2942       if (GVFun) {
2943         // References to a function via function pointers generate virtual
2944         // registers without a definition. We will resolve it later, during
2945         // module analysis stage.
2946         MachineRegisterInfo *MRI = MIRBuilder.getMRI();
2947         Register FuncVReg = MRI->createGenericVirtualRegister(LLT::scalar(64));
2948         MRI->setRegClass(FuncVReg, &SPIRV::iIDRegClass);
2949         MachineInstrBuilder MB =
2950             BuildMI(BB, I, I.getDebugLoc(),
2951                     TII.get(SPIRV::OpConstantFunctionPointerINTEL))
2952                 .addDef(NewReg)
2953                 .addUse(GR.getSPIRVTypeID(ResType))
2954                 .addUse(FuncVReg);
2955         // mapping the function pointer to the used Function
2956         GR.recordFunctionPointer(&MB.getInstr()->getOperand(2), GVFun);
2957         return MB.constrainAllUses(TII, TRI, RBI);
2958       }
2959       return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
2960           .addDef(NewReg)
2961           .addUse(GR.getSPIRVTypeID(ResType))
2962           .constrainAllUses(TII, TRI, RBI);
2963     }
2964     assert(NewReg != ResVReg);
2965     return BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY))
2966         .addDef(ResVReg)
2967         .addUse(NewReg)
2968         .constrainAllUses(TII, TRI, RBI);
2969   }
2970   auto GlobalVar = cast<GlobalVariable>(GV);
2971   assert(GlobalVar->getName() != "llvm.global.annotations");
2972 
2973   bool HasInit = GlobalVar->hasInitializer() &&
2974                  !isa<UndefValue>(GlobalVar->getInitializer());
2975   // Skip empty declaration for GVs with initilaizers till we get the decl with
2976   // passed initializer.
2977   if (HasInit && !Init)
2978     return true;
2979 
2980   unsigned AddrSpace = GV->getAddressSpace();
2981   SPIRV::StorageClass::StorageClass Storage =
2982       addressSpaceToStorageClass(AddrSpace, STI);
2983   bool HasLnkTy = GV->getLinkage() != GlobalValue::InternalLinkage &&
2984                   Storage != SPIRV::StorageClass::Function;
2985   SPIRV::LinkageType::LinkageType LnkType =
2986       (GV->isDeclaration() || GV->hasAvailableExternallyLinkage())
2987           ? SPIRV::LinkageType::Import
2988           : (GV->getLinkage() == GlobalValue::LinkOnceODRLinkage &&
2989                      STI.canUseExtension(SPIRV::Extension::SPV_KHR_linkonce_odr)
2990                  ? SPIRV::LinkageType::LinkOnceODR
2991                  : SPIRV::LinkageType::Export);
2992 
2993   Register Reg = GR.buildGlobalVariable(ResVReg, ResType, GlobalIdent, GV,
2994                                         Storage, Init, GlobalVar->isConstant(),
2995                                         HasLnkTy, LnkType, MIRBuilder, true);
2996   return Reg.isValid();
2997 }
2998 
2999 bool SPIRVInstructionSelector::selectLog10(Register ResVReg,
3000                                            const SPIRVType *ResType,
3001                                            MachineInstr &I) const {
3002   if (STI.canUseExtInstSet(SPIRV::InstructionSet::OpenCL_std)) {
3003     return selectExtInst(ResVReg, ResType, I, CL::log10);
3004   }
3005 
3006   // There is no log10 instruction in the GLSL Extended Instruction set, so it
3007   // is implemented as:
3008   // log10(x) = log2(x) * (1 / log2(10))
3009   //          = log2(x) * 0.30103
3010 
3011   MachineIRBuilder MIRBuilder(I);
3012   MachineBasicBlock &BB = *I.getParent();
3013 
3014   // Build log2(x).
3015   Register VarReg = MRI->createVirtualRegister(GR.getRegClass(ResType));
3016   bool Result =
3017       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
3018           .addDef(VarReg)
3019           .addUse(GR.getSPIRVTypeID(ResType))
3020           .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
3021           .addImm(GL::Log2)
3022           .add(I.getOperand(1))
3023           .constrainAllUses(TII, TRI, RBI);
3024 
3025   // Build 0.30103.
3026   assert(ResType->getOpcode() == SPIRV::OpTypeVector ||
3027          ResType->getOpcode() == SPIRV::OpTypeFloat);
3028   // TODO: Add matrix implementation once supported by the HLSL frontend.
3029   const SPIRVType *SpirvScalarType =
3030       ResType->getOpcode() == SPIRV::OpTypeVector
3031           ? GR.getSPIRVTypeForVReg(ResType->getOperand(1).getReg())
3032           : ResType;
3033   Register ScaleReg =
3034       GR.buildConstantFP(APFloat(0.30103f), MIRBuilder, SpirvScalarType);
3035 
3036   // Multiply log2(x) by 0.30103 to get log10(x) result.
3037   auto Opcode = ResType->getOpcode() == SPIRV::OpTypeVector
3038                     ? SPIRV::OpVectorTimesScalar
3039                     : SPIRV::OpFMulS;
3040   Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
3041                 .addDef(ResVReg)
3042                 .addUse(GR.getSPIRVTypeID(ResType))
3043                 .addUse(VarReg)
3044                 .addUse(ScaleReg)
3045                 .constrainAllUses(TII, TRI, RBI);
3046 
3047   return Result;
3048 }
3049 
3050 bool SPIRVInstructionSelector::selectSpvThreadId(Register ResVReg,
3051                                                  const SPIRVType *ResType,
3052                                                  MachineInstr &I) const {
3053   // DX intrinsic: @llvm.dx.thread.id(i32)
3054   // ID  Name      Description
3055   // 93  ThreadId  reads the thread ID
3056 
3057   MachineIRBuilder MIRBuilder(I);
3058   const SPIRVType *U32Type = GR.getOrCreateSPIRVIntegerType(32, MIRBuilder);
3059   const SPIRVType *Vec3Ty =
3060       GR.getOrCreateSPIRVVectorType(U32Type, 3, MIRBuilder);
3061   const SPIRVType *PtrType = GR.getOrCreateSPIRVPointerType(
3062       Vec3Ty, MIRBuilder, SPIRV::StorageClass::Input);
3063 
3064   // Create new register for GlobalInvocationID builtin variable.
3065   Register NewRegister =
3066       MIRBuilder.getMRI()->createVirtualRegister(&SPIRV::iIDRegClass);
3067   MIRBuilder.getMRI()->setType(NewRegister, LLT::pointer(0, 64));
3068   GR.assignSPIRVTypeToVReg(PtrType, NewRegister, MIRBuilder.getMF());
3069 
3070   // Build GlobalInvocationID global variable with the necessary decorations.
3071   Register Variable = GR.buildGlobalVariable(
3072       NewRegister, PtrType,
3073       getLinkStringForBuiltIn(SPIRV::BuiltIn::GlobalInvocationId), nullptr,
3074       SPIRV::StorageClass::Input, nullptr, true, true,
3075       SPIRV::LinkageType::Import, MIRBuilder, false);
3076 
3077   // Create new register for loading value.
3078   MachineRegisterInfo *MRI = MIRBuilder.getMRI();
3079   Register LoadedRegister = MRI->createVirtualRegister(&SPIRV::iIDRegClass);
3080   MIRBuilder.getMRI()->setType(LoadedRegister, LLT::pointer(0, 64));
3081   GR.assignSPIRVTypeToVReg(Vec3Ty, LoadedRegister, MIRBuilder.getMF());
3082 
3083   // Load v3uint value from the global variable.
3084   BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
3085       .addDef(LoadedRegister)
3086       .addUse(GR.getSPIRVTypeID(Vec3Ty))
3087       .addUse(Variable);
3088 
3089   // Get Thread ID index. Expecting operand is a constant immediate value,
3090   // wrapped in a type assignment.
3091   assert(I.getOperand(2).isReg());
3092   const uint32_t ThreadId = foldImm(I.getOperand(2), MRI);
3093 
3094   // Extract the thread ID from the loaded vector value.
3095   MachineBasicBlock &BB = *I.getParent();
3096   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
3097                  .addDef(ResVReg)
3098                  .addUse(GR.getSPIRVTypeID(ResType))
3099                  .addUse(LoadedRegister)
3100                  .addImm(ThreadId);
3101   return MIB.constrainAllUses(TII, TRI, RBI);
3102 }
3103 
3104 namespace llvm {
3105 InstructionSelector *
3106 createSPIRVInstructionSelector(const SPIRVTargetMachine &TM,
3107                                const SPIRVSubtarget &Subtarget,
3108                                const RegisterBankInfo &RBI) {
3109   return new SPIRVInstructionSelector(TM, Subtarget, RBI);
3110 }
3111 } // namespace llvm
3112