xref: /llvm-project/llvm/lib/Target/SPIRV/SPIRVInstructionSelector.cpp (revision 57f79371a5c08e1328e85b68b757cd5547f2bf62)
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/TargetOpcodes.h"
32 #include "llvm/IR/IntrinsicsSPIRV.h"
33 #include "llvm/Support/Debug.h"
34 
35 namespace llvm {
36 
37 class SPIRVMachineModuleInfo : public MachineModuleInfoImpl {
38 public:
39   SyncScope::ID Work_ItemSSID;
40   SyncScope::ID WorkGroupSSID;
41   SyncScope::ID DeviceSSID;
42   SyncScope::ID AllSVMDevicesSSID;
43   SyncScope::ID SubGroupSSID;
44 
45   SPIRVMachineModuleInfo(const MachineModuleInfo &MMI) {
46     LLVMContext &CTX = MMI.getModule()->getContext();
47     Work_ItemSSID = CTX.getOrInsertSyncScopeID("work_item");
48     WorkGroupSSID = CTX.getOrInsertSyncScopeID("workgroup");
49     DeviceSSID = CTX.getOrInsertSyncScopeID("device");
50     AllSVMDevicesSSID = CTX.getOrInsertSyncScopeID("all_svm_devices");
51     SubGroupSSID = CTX.getOrInsertSyncScopeID("sub_group");
52   }
53 };
54 
55 } // end namespace llvm
56 
57 #define DEBUG_TYPE "spirv-isel"
58 
59 using namespace llvm;
60 namespace CL = SPIRV::OpenCLExtInst;
61 namespace GL = SPIRV::GLSLExtInst;
62 
63 using ExtInstList =
64     std::vector<std::pair<SPIRV::InstructionSet::InstructionSet, uint32_t>>;
65 
66 namespace {
67 
68 #define GET_GLOBALISEL_PREDICATE_BITSET
69 #include "SPIRVGenGlobalISel.inc"
70 #undef GET_GLOBALISEL_PREDICATE_BITSET
71 
72 class SPIRVInstructionSelector : public InstructionSelector {
73   const SPIRVSubtarget &STI;
74   const SPIRVInstrInfo &TII;
75   const SPIRVRegisterInfo &TRI;
76   const RegisterBankInfo &RBI;
77   SPIRVGlobalRegistry &GR;
78   MachineRegisterInfo *MRI;
79   SPIRVMachineModuleInfo *MMI = nullptr;
80 
81   /// We need to keep track of the number we give to anonymous global values to
82   /// generate the same name every time when this is needed.
83   mutable DenseMap<const GlobalValue *, unsigned> UnnamedGlobalIDs;
84 
85 public:
86   SPIRVInstructionSelector(const SPIRVTargetMachine &TM,
87                            const SPIRVSubtarget &ST,
88                            const RegisterBankInfo &RBI);
89   void setupMF(MachineFunction &MF, GISelKnownBits *KB,
90                CodeGenCoverage *CoverageInfo, ProfileSummaryInfo *PSI,
91                BlockFrequencyInfo *BFI) override;
92   // Common selection code. Instruction-specific selection occurs in spvSelect.
93   bool select(MachineInstr &I) override;
94   static const char *getName() { return DEBUG_TYPE; }
95 
96 #define GET_GLOBALISEL_PREDICATES_DECL
97 #include "SPIRVGenGlobalISel.inc"
98 #undef GET_GLOBALISEL_PREDICATES_DECL
99 
100 #define GET_GLOBALISEL_TEMPORARIES_DECL
101 #include "SPIRVGenGlobalISel.inc"
102 #undef GET_GLOBALISEL_TEMPORARIES_DECL
103 
104 private:
105   // tblgen-erated 'select' implementation, used as the initial selector for
106   // the patterns that don't require complex C++.
107   bool selectImpl(MachineInstr &I, CodeGenCoverage &CoverageInfo) const;
108 
109   // All instruction-specific selection that didn't happen in "select()".
110   // Is basically a large Switch/Case delegating to all other select method.
111   bool spvSelect(Register ResVReg, const SPIRVType *ResType,
112                  MachineInstr &I) const;
113 
114   bool selectGlobalValue(Register ResVReg, MachineInstr &I,
115                          const MachineInstr *Init = nullptr) const;
116 
117   bool selectUnOpWithSrc(Register ResVReg, const SPIRVType *ResType,
118                          MachineInstr &I, Register SrcReg,
119                          unsigned Opcode) const;
120   bool selectUnOp(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
121                   unsigned Opcode) const;
122 
123   bool selectBitcast(Register ResVReg, const SPIRVType *ResType,
124                      MachineInstr &I) const;
125 
126   bool selectLoad(Register ResVReg, const SPIRVType *ResType,
127                   MachineInstr &I) const;
128   bool selectStore(MachineInstr &I) const;
129 
130   bool selectStackSave(Register ResVReg, const SPIRVType *ResType,
131                        MachineInstr &I) const;
132   bool selectStackRestore(MachineInstr &I) const;
133 
134   bool selectMemOperation(Register ResVReg, MachineInstr &I) const;
135 
136   bool selectAtomicRMW(Register ResVReg, const SPIRVType *ResType,
137                        MachineInstr &I, unsigned NewOpcode,
138                        unsigned NegateOpcode = 0) const;
139 
140   bool selectAtomicCmpXchg(Register ResVReg, const SPIRVType *ResType,
141                            MachineInstr &I) const;
142 
143   bool selectFence(MachineInstr &I) const;
144 
145   bool selectAddrSpaceCast(Register ResVReg, const SPIRVType *ResType,
146                            MachineInstr &I) const;
147 
148   bool selectAnyOrAll(Register ResVReg, const SPIRVType *ResType,
149                       MachineInstr &I, unsigned OpType) const;
150 
151   bool selectAll(Register ResVReg, const SPIRVType *ResType,
152                  MachineInstr &I) const;
153 
154   bool selectAny(Register ResVReg, const SPIRVType *ResType,
155                  MachineInstr &I) const;
156 
157   bool selectBitreverse(Register ResVReg, const SPIRVType *ResType,
158                         MachineInstr &I) const;
159 
160   bool selectConstVector(Register ResVReg, const SPIRVType *ResType,
161                          MachineInstr &I) const;
162   bool selectSplatVector(Register ResVReg, const SPIRVType *ResType,
163                          MachineInstr &I) const;
164 
165   bool selectCmp(Register ResVReg, const SPIRVType *ResType,
166                  unsigned comparisonOpcode, MachineInstr &I) const;
167 
168   bool selectICmp(Register ResVReg, const SPIRVType *ResType,
169                   MachineInstr &I) const;
170   bool selectFCmp(Register ResVReg, const SPIRVType *ResType,
171                   MachineInstr &I) const;
172 
173   bool selectFmix(Register ResVReg, const SPIRVType *ResType,
174                   MachineInstr &I) const;
175 
176   bool selectRsqrt(Register ResVReg, const SPIRVType *ResType,
177                    MachineInstr &I) const;
178 
179   void renderImm32(MachineInstrBuilder &MIB, const MachineInstr &I,
180                    int OpIdx) const;
181   void renderFImm32(MachineInstrBuilder &MIB, const MachineInstr &I,
182                     int OpIdx) const;
183 
184   bool selectConst(Register ResVReg, const SPIRVType *ResType, const APInt &Imm,
185                    MachineInstr &I) const;
186 
187   bool selectSelect(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
188                     bool IsSigned) const;
189   bool selectIToF(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
190                   bool IsSigned, unsigned Opcode) const;
191   bool selectExt(Register ResVReg, const SPIRVType *ResType, MachineInstr &I,
192                  bool IsSigned) const;
193 
194   bool selectTrunc(Register ResVReg, const SPIRVType *ResType,
195                    MachineInstr &I) const;
196 
197   bool selectIntToBool(Register IntReg, Register ResVReg, MachineInstr &I,
198                        const SPIRVType *intTy, const SPIRVType *boolTy) const;
199 
200   bool selectOpUndef(Register ResVReg, const SPIRVType *ResType,
201                      MachineInstr &I) const;
202   bool selectFreeze(Register ResVReg, const SPIRVType *ResType,
203                     MachineInstr &I) const;
204   bool selectIntrinsic(Register ResVReg, const SPIRVType *ResType,
205                        MachineInstr &I) const;
206   bool selectExtractVal(Register ResVReg, const SPIRVType *ResType,
207                         MachineInstr &I) const;
208   bool selectInsertVal(Register ResVReg, const SPIRVType *ResType,
209                        MachineInstr &I) const;
210   bool selectExtractElt(Register ResVReg, const SPIRVType *ResType,
211                         MachineInstr &I) const;
212   bool selectInsertElt(Register ResVReg, const SPIRVType *ResType,
213                        MachineInstr &I) const;
214   bool selectGEP(Register ResVReg, const SPIRVType *ResType,
215                  MachineInstr &I) const;
216 
217   bool selectFrameIndex(Register ResVReg, const SPIRVType *ResType,
218                         MachineInstr &I) const;
219   bool selectAllocaArray(Register ResVReg, const SPIRVType *ResType,
220                          MachineInstr &I) const;
221 
222   bool selectBranch(MachineInstr &I) const;
223   bool selectBranchCond(MachineInstr &I) const;
224 
225   bool selectPhi(Register ResVReg, const SPIRVType *ResType,
226                  MachineInstr &I) const;
227 
228   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
229                      MachineInstr &I, CL::OpenCLExtInst CLInst) const;
230   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
231                      MachineInstr &I, CL::OpenCLExtInst CLInst,
232                      GL::GLSLExtInst GLInst) const;
233   bool selectExtInst(Register ResVReg, const SPIRVType *ResType,
234                      MachineInstr &I, const ExtInstList &ExtInsts) const;
235 
236   bool selectLog10(Register ResVReg, const SPIRVType *ResType,
237                    MachineInstr &I) const;
238 
239   bool selectSpvThreadId(Register ResVReg, const SPIRVType *ResType,
240                          MachineInstr &I) const;
241 
242   bool selectUnmergeValues(MachineInstr &I) const;
243 
244   Register buildI32Constant(uint32_t Val, MachineInstr &I,
245                             const SPIRVType *ResType = nullptr) const;
246 
247   Register buildZerosVal(const SPIRVType *ResType, MachineInstr &I) const;
248   Register buildZerosValF(const SPIRVType *ResType, MachineInstr &I) const;
249   Register buildOnesVal(bool AllOnes, const SPIRVType *ResType,
250                         MachineInstr &I) const;
251 
252   bool wrapIntoSpecConstantOp(MachineInstr &I,
253                               SmallVector<Register> &CompositeArgs) const;
254 };
255 
256 } // end anonymous namespace
257 
258 #define GET_GLOBALISEL_IMPL
259 #include "SPIRVGenGlobalISel.inc"
260 #undef GET_GLOBALISEL_IMPL
261 
262 SPIRVInstructionSelector::SPIRVInstructionSelector(const SPIRVTargetMachine &TM,
263                                                    const SPIRVSubtarget &ST,
264                                                    const RegisterBankInfo &RBI)
265     : InstructionSelector(), STI(ST), TII(*ST.getInstrInfo()),
266       TRI(*ST.getRegisterInfo()), RBI(RBI), GR(*ST.getSPIRVGlobalRegistry()),
267 #define GET_GLOBALISEL_PREDICATES_INIT
268 #include "SPIRVGenGlobalISel.inc"
269 #undef GET_GLOBALISEL_PREDICATES_INIT
270 #define GET_GLOBALISEL_TEMPORARIES_INIT
271 #include "SPIRVGenGlobalISel.inc"
272 #undef GET_GLOBALISEL_TEMPORARIES_INIT
273 {
274 }
275 
276 void SPIRVInstructionSelector::setupMF(MachineFunction &MF, GISelKnownBits *KB,
277                                        CodeGenCoverage *CoverageInfo,
278                                        ProfileSummaryInfo *PSI,
279                                        BlockFrequencyInfo *BFI) {
280   MMI = &MF.getMMI().getObjFileInfo<SPIRVMachineModuleInfo>();
281   MRI = &MF.getRegInfo();
282   GR.setCurrentFunc(MF);
283   InstructionSelector::setupMF(MF, KB, CoverageInfo, PSI, BFI);
284 }
285 
286 static bool isImm(const MachineOperand &MO, MachineRegisterInfo *MRI);
287 
288 // Defined in SPIRVLegalizerInfo.cpp.
289 extern bool isTypeFoldingSupported(unsigned Opcode);
290 
291 bool SPIRVInstructionSelector::select(MachineInstr &I) {
292   assert(I.getParent() && "Instruction should be in a basic block!");
293   assert(I.getParent()->getParent() && "Instruction should be in a function!");
294 
295   Register Opcode = I.getOpcode();
296   // If it's not a GMIR instruction, we've selected it already.
297   if (!isPreISelGenericOpcode(Opcode)) {
298     if (Opcode == SPIRV::ASSIGN_TYPE) { // These pseudos aren't needed any more.
299       Register DstReg = I.getOperand(0).getReg();
300       Register SrcReg = I.getOperand(1).getReg();
301       auto *Def = MRI->getVRegDef(SrcReg);
302       if (isTypeFoldingSupported(Def->getOpcode())) {
303         if (MRI->getType(DstReg).isPointer())
304           MRI->setType(DstReg, LLT::scalar(32));
305         bool Res = selectImpl(I, *CoverageInfo);
306         assert(Res || Def->getOpcode() == TargetOpcode::G_CONSTANT);
307         if (Res)
308           return Res;
309       }
310       MRI->replaceRegWith(SrcReg, DstReg);
311       I.removeFromParent();
312       return true;
313     } else if (I.getNumDefs() == 1) {
314       // Make all vregs 32 bits (for SPIR-V IDs).
315       MRI->setType(I.getOperand(0).getReg(), LLT::scalar(32));
316     }
317     return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
318   }
319 
320   if (I.getNumOperands() != I.getNumExplicitOperands()) {
321     LLVM_DEBUG(errs() << "Generic instr has unexpected implicit operands\n");
322     return false;
323   }
324 
325   // Common code for getting return reg+type, and removing selected instr
326   // from parent occurs here. Instr-specific selection happens in spvSelect().
327   bool HasDefs = I.getNumDefs() > 0;
328   Register ResVReg = HasDefs ? I.getOperand(0).getReg() : Register(0);
329   SPIRVType *ResType = HasDefs ? GR.getSPIRVTypeForVReg(ResVReg) : nullptr;
330   assert(!HasDefs || ResType || I.getOpcode() == TargetOpcode::G_GLOBAL_VALUE);
331   if (spvSelect(ResVReg, ResType, I)) {
332     if (HasDefs) // Make all vregs 32 bits (for SPIR-V IDs).
333       for (unsigned i = 0; i < I.getNumDefs(); ++i)
334         MRI->setType(I.getOperand(i).getReg(), LLT::scalar(32));
335     I.removeFromParent();
336     return true;
337   }
338   return false;
339 }
340 
341 bool SPIRVInstructionSelector::spvSelect(Register ResVReg,
342                                          const SPIRVType *ResType,
343                                          MachineInstr &I) const {
344   const unsigned Opcode = I.getOpcode();
345   if (isTypeFoldingSupported(Opcode) && Opcode != TargetOpcode::G_CONSTANT)
346     return selectImpl(I, *CoverageInfo);
347   switch (Opcode) {
348   case TargetOpcode::G_CONSTANT:
349     return selectConst(ResVReg, ResType, I.getOperand(1).getCImm()->getValue(),
350                        I);
351   case TargetOpcode::G_GLOBAL_VALUE:
352     return selectGlobalValue(ResVReg, I);
353   case TargetOpcode::G_IMPLICIT_DEF:
354     return selectOpUndef(ResVReg, ResType, I);
355   case TargetOpcode::G_FREEZE:
356     return selectFreeze(ResVReg, ResType, I);
357 
358   case TargetOpcode::G_INTRINSIC:
359   case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
360   case TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS:
361     return selectIntrinsic(ResVReg, ResType, I);
362   case TargetOpcode::G_BITREVERSE:
363     return selectBitreverse(ResVReg, ResType, I);
364 
365   case TargetOpcode::G_BUILD_VECTOR:
366     return selectConstVector(ResVReg, ResType, I);
367   case TargetOpcode::G_SPLAT_VECTOR:
368     return selectSplatVector(ResVReg, ResType, I);
369 
370   case TargetOpcode::G_SHUFFLE_VECTOR: {
371     MachineBasicBlock &BB = *I.getParent();
372     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorShuffle))
373                    .addDef(ResVReg)
374                    .addUse(GR.getSPIRVTypeID(ResType))
375                    .addUse(I.getOperand(1).getReg())
376                    .addUse(I.getOperand(2).getReg());
377     for (auto V : I.getOperand(3).getShuffleMask())
378       MIB.addImm(V);
379     return MIB.constrainAllUses(TII, TRI, RBI);
380   }
381   case TargetOpcode::G_MEMMOVE:
382   case TargetOpcode::G_MEMCPY:
383   case TargetOpcode::G_MEMSET:
384     return selectMemOperation(ResVReg, I);
385 
386   case TargetOpcode::G_ICMP:
387     return selectICmp(ResVReg, ResType, I);
388   case TargetOpcode::G_FCMP:
389     return selectFCmp(ResVReg, ResType, I);
390 
391   case TargetOpcode::G_FRAME_INDEX:
392     return selectFrameIndex(ResVReg, ResType, I);
393 
394   case TargetOpcode::G_LOAD:
395     return selectLoad(ResVReg, ResType, I);
396   case TargetOpcode::G_STORE:
397     return selectStore(I);
398 
399   case TargetOpcode::G_BR:
400     return selectBranch(I);
401   case TargetOpcode::G_BRCOND:
402     return selectBranchCond(I);
403 
404   case TargetOpcode::G_PHI:
405     return selectPhi(ResVReg, ResType, I);
406 
407   case TargetOpcode::G_FPTOSI:
408     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertFToS);
409   case TargetOpcode::G_FPTOUI:
410     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertFToU);
411 
412   case TargetOpcode::G_SITOFP:
413     return selectIToF(ResVReg, ResType, I, true, SPIRV::OpConvertSToF);
414   case TargetOpcode::G_UITOFP:
415     return selectIToF(ResVReg, ResType, I, false, SPIRV::OpConvertUToF);
416 
417   case TargetOpcode::G_CTPOP:
418     return selectUnOp(ResVReg, ResType, I, SPIRV::OpBitCount);
419   case TargetOpcode::G_SMIN:
420     return selectExtInst(ResVReg, ResType, I, CL::s_min, GL::SMin);
421   case TargetOpcode::G_UMIN:
422     return selectExtInst(ResVReg, ResType, I, CL::u_min, GL::UMin);
423 
424   case TargetOpcode::G_SMAX:
425     return selectExtInst(ResVReg, ResType, I, CL::s_max, GL::SMax);
426   case TargetOpcode::G_UMAX:
427     return selectExtInst(ResVReg, ResType, I, CL::u_max, GL::UMax);
428 
429   case TargetOpcode::G_FMA:
430     return selectExtInst(ResVReg, ResType, I, CL::fma, GL::Fma);
431 
432   case TargetOpcode::G_FPOW:
433     return selectExtInst(ResVReg, ResType, I, CL::pow, GL::Pow);
434   case TargetOpcode::G_FPOWI:
435     return selectExtInst(ResVReg, ResType, I, CL::pown);
436 
437   case TargetOpcode::G_FEXP:
438     return selectExtInst(ResVReg, ResType, I, CL::exp, GL::Exp);
439   case TargetOpcode::G_FEXP2:
440     return selectExtInst(ResVReg, ResType, I, CL::exp2, GL::Exp2);
441 
442   case TargetOpcode::G_FLOG:
443     return selectExtInst(ResVReg, ResType, I, CL::log, GL::Log);
444   case TargetOpcode::G_FLOG2:
445     return selectExtInst(ResVReg, ResType, I, CL::log2, GL::Log2);
446   case TargetOpcode::G_FLOG10:
447     return selectLog10(ResVReg, ResType, I);
448 
449   case TargetOpcode::G_FABS:
450     return selectExtInst(ResVReg, ResType, I, CL::fabs, GL::FAbs);
451   case TargetOpcode::G_ABS:
452     return selectExtInst(ResVReg, ResType, I, CL::s_abs, GL::SAbs);
453 
454   case TargetOpcode::G_FMINNUM:
455   case TargetOpcode::G_FMINIMUM:
456     return selectExtInst(ResVReg, ResType, I, CL::fmin, GL::NMin);
457   case TargetOpcode::G_FMAXNUM:
458   case TargetOpcode::G_FMAXIMUM:
459     return selectExtInst(ResVReg, ResType, I, CL::fmax, GL::NMax);
460 
461   case TargetOpcode::G_FCOPYSIGN:
462     return selectExtInst(ResVReg, ResType, I, CL::copysign);
463 
464   case TargetOpcode::G_FCEIL:
465     return selectExtInst(ResVReg, ResType, I, CL::ceil, GL::Ceil);
466   case TargetOpcode::G_FFLOOR:
467     return selectExtInst(ResVReg, ResType, I, CL::floor, GL::Floor);
468 
469   case TargetOpcode::G_FCOS:
470     return selectExtInst(ResVReg, ResType, I, CL::cos, GL::Cos);
471   case TargetOpcode::G_FSIN:
472     return selectExtInst(ResVReg, ResType, I, CL::sin, GL::Sin);
473   case TargetOpcode::G_FTAN:
474     return selectExtInst(ResVReg, ResType, I, CL::tan, GL::Tan);
475   case TargetOpcode::G_FACOS:
476     return selectExtInst(ResVReg, ResType, I, CL::acos, GL::Acos);
477   case TargetOpcode::G_FASIN:
478     return selectExtInst(ResVReg, ResType, I, CL::asin, GL::Asin);
479   case TargetOpcode::G_FATAN:
480     return selectExtInst(ResVReg, ResType, I, CL::atan, GL::Atan);
481   case TargetOpcode::G_FCOSH:
482     return selectExtInst(ResVReg, ResType, I, CL::cosh, GL::Cosh);
483   case TargetOpcode::G_FSINH:
484     return selectExtInst(ResVReg, ResType, I, CL::sinh, GL::Sinh);
485   case TargetOpcode::G_FTANH:
486     return selectExtInst(ResVReg, ResType, I, CL::tanh, GL::Tanh);
487 
488   case TargetOpcode::G_FSQRT:
489     return selectExtInst(ResVReg, ResType, I, CL::sqrt, GL::Sqrt);
490 
491   case TargetOpcode::G_CTTZ:
492   case TargetOpcode::G_CTTZ_ZERO_UNDEF:
493     return selectExtInst(ResVReg, ResType, I, CL::ctz);
494   case TargetOpcode::G_CTLZ:
495   case TargetOpcode::G_CTLZ_ZERO_UNDEF:
496     return selectExtInst(ResVReg, ResType, I, CL::clz);
497 
498   case TargetOpcode::G_INTRINSIC_ROUND:
499     return selectExtInst(ResVReg, ResType, I, CL::round, GL::Round);
500   case TargetOpcode::G_INTRINSIC_ROUNDEVEN:
501     return selectExtInst(ResVReg, ResType, I, CL::rint, GL::RoundEven);
502   case TargetOpcode::G_INTRINSIC_TRUNC:
503     return selectExtInst(ResVReg, ResType, I, CL::trunc, GL::Trunc);
504   case TargetOpcode::G_FRINT:
505   case TargetOpcode::G_FNEARBYINT:
506     return selectExtInst(ResVReg, ResType, I, CL::rint, GL::RoundEven);
507 
508   case TargetOpcode::G_SMULH:
509     return selectExtInst(ResVReg, ResType, I, CL::s_mul_hi);
510   case TargetOpcode::G_UMULH:
511     return selectExtInst(ResVReg, ResType, I, CL::u_mul_hi);
512 
513   case TargetOpcode::G_SADDSAT:
514     return selectExtInst(ResVReg, ResType, I, CL::s_add_sat);
515   case TargetOpcode::G_UADDSAT:
516     return selectExtInst(ResVReg, ResType, I, CL::u_add_sat);
517   case TargetOpcode::G_SSUBSAT:
518     return selectExtInst(ResVReg, ResType, I, CL::s_sub_sat);
519   case TargetOpcode::G_USUBSAT:
520     return selectExtInst(ResVReg, ResType, I, CL::u_sub_sat);
521 
522   case TargetOpcode::G_SEXT:
523     return selectExt(ResVReg, ResType, I, true);
524   case TargetOpcode::G_ANYEXT:
525   case TargetOpcode::G_ZEXT:
526     return selectExt(ResVReg, ResType, I, false);
527   case TargetOpcode::G_TRUNC:
528     return selectTrunc(ResVReg, ResType, I);
529   case TargetOpcode::G_FPTRUNC:
530   case TargetOpcode::G_FPEXT:
531     return selectUnOp(ResVReg, ResType, I, SPIRV::OpFConvert);
532 
533   case TargetOpcode::G_PTRTOINT:
534     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertPtrToU);
535   case TargetOpcode::G_INTTOPTR:
536     return selectUnOp(ResVReg, ResType, I, SPIRV::OpConvertUToPtr);
537   case TargetOpcode::G_BITCAST:
538     return selectBitcast(ResVReg, ResType, I);
539   case TargetOpcode::G_ADDRSPACE_CAST:
540     return selectAddrSpaceCast(ResVReg, ResType, I);
541   case TargetOpcode::G_PTR_ADD: {
542     // Currently, we get G_PTR_ADD only as a result of translating
543     // global variables, initialized with constant expressions like GV + Const
544     // (see test opencl/basic/progvar_prog_scope_init.ll).
545     // TODO: extend the handler once we have other cases.
546     assert(I.getOperand(1).isReg() && I.getOperand(2).isReg());
547     Register GV = I.getOperand(1).getReg();
548     MachineRegisterInfo::def_instr_iterator II = MRI->def_instr_begin(GV);
549     (void)II;
550     assert(((*II).getOpcode() == TargetOpcode::G_GLOBAL_VALUE ||
551             (*II).getOpcode() == TargetOpcode::COPY ||
552             (*II).getOpcode() == SPIRV::OpVariable) &&
553            isImm(I.getOperand(2), MRI));
554     Register Idx = buildZerosVal(GR.getOrCreateSPIRVIntegerType(32, I, TII), I);
555     MachineBasicBlock &BB = *I.getParent();
556     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
557                    .addDef(ResVReg)
558                    .addUse(GR.getSPIRVTypeID(ResType))
559                    .addImm(static_cast<uint32_t>(
560                        SPIRV::Opcode::InBoundsPtrAccessChain))
561                    .addUse(GV)
562                    .addUse(Idx)
563                    .addUse(I.getOperand(2).getReg());
564     return MIB.constrainAllUses(TII, TRI, RBI);
565   }
566 
567   case TargetOpcode::G_ATOMICRMW_OR:
568     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicOr);
569   case TargetOpcode::G_ATOMICRMW_ADD:
570     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicIAdd);
571   case TargetOpcode::G_ATOMICRMW_AND:
572     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicAnd);
573   case TargetOpcode::G_ATOMICRMW_MAX:
574     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicSMax);
575   case TargetOpcode::G_ATOMICRMW_MIN:
576     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicSMin);
577   case TargetOpcode::G_ATOMICRMW_SUB:
578     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicISub);
579   case TargetOpcode::G_ATOMICRMW_XOR:
580     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicXor);
581   case TargetOpcode::G_ATOMICRMW_UMAX:
582     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicUMax);
583   case TargetOpcode::G_ATOMICRMW_UMIN:
584     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicUMin);
585   case TargetOpcode::G_ATOMICRMW_XCHG:
586     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicExchange);
587   case TargetOpcode::G_ATOMIC_CMPXCHG:
588     return selectAtomicCmpXchg(ResVReg, ResType, I);
589 
590   case TargetOpcode::G_ATOMICRMW_FADD:
591     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFAddEXT);
592   case TargetOpcode::G_ATOMICRMW_FSUB:
593     // Translate G_ATOMICRMW_FSUB to OpAtomicFAddEXT with negative value operand
594     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFAddEXT,
595                            SPIRV::OpFNegate);
596   case TargetOpcode::G_ATOMICRMW_FMIN:
597     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFMinEXT);
598   case TargetOpcode::G_ATOMICRMW_FMAX:
599     return selectAtomicRMW(ResVReg, ResType, I, SPIRV::OpAtomicFMaxEXT);
600 
601   case TargetOpcode::G_FENCE:
602     return selectFence(I);
603 
604   case TargetOpcode::G_STACKSAVE:
605     return selectStackSave(ResVReg, ResType, I);
606   case TargetOpcode::G_STACKRESTORE:
607     return selectStackRestore(I);
608 
609   case TargetOpcode::G_UNMERGE_VALUES:
610     return selectUnmergeValues(I);
611 
612   default:
613     return false;
614   }
615 }
616 
617 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
618                                              const SPIRVType *ResType,
619                                              MachineInstr &I,
620                                              CL::OpenCLExtInst CLInst) const {
621   return selectExtInst(ResVReg, ResType, I,
622                        {{SPIRV::InstructionSet::OpenCL_std, CLInst}});
623 }
624 
625 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
626                                              const SPIRVType *ResType,
627                                              MachineInstr &I,
628                                              CL::OpenCLExtInst CLInst,
629                                              GL::GLSLExtInst GLInst) const {
630   ExtInstList ExtInsts = {{SPIRV::InstructionSet::OpenCL_std, CLInst},
631                           {SPIRV::InstructionSet::GLSL_std_450, GLInst}};
632   return selectExtInst(ResVReg, ResType, I, ExtInsts);
633 }
634 
635 bool SPIRVInstructionSelector::selectExtInst(Register ResVReg,
636                                              const SPIRVType *ResType,
637                                              MachineInstr &I,
638                                              const ExtInstList &Insts) const {
639 
640   for (const auto &Ex : Insts) {
641     SPIRV::InstructionSet::InstructionSet Set = Ex.first;
642     uint32_t Opcode = Ex.second;
643     if (STI.canUseExtInstSet(Set)) {
644       MachineBasicBlock &BB = *I.getParent();
645       auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
646                      .addDef(ResVReg)
647                      .addUse(GR.getSPIRVTypeID(ResType))
648                      .addImm(static_cast<uint32_t>(Set))
649                      .addImm(Opcode);
650       const unsigned NumOps = I.getNumOperands();
651       for (unsigned i = 1; i < NumOps; ++i)
652         MIB.add(I.getOperand(i));
653       return MIB.constrainAllUses(TII, TRI, RBI);
654     }
655   }
656   return false;
657 }
658 
659 bool SPIRVInstructionSelector::selectUnOpWithSrc(Register ResVReg,
660                                                  const SPIRVType *ResType,
661                                                  MachineInstr &I,
662                                                  Register SrcReg,
663                                                  unsigned Opcode) const {
664   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
665       .addDef(ResVReg)
666       .addUse(GR.getSPIRVTypeID(ResType))
667       .addUse(SrcReg)
668       .constrainAllUses(TII, TRI, RBI);
669 }
670 
671 bool SPIRVInstructionSelector::selectUnOp(Register ResVReg,
672                                           const SPIRVType *ResType,
673                                           MachineInstr &I,
674                                           unsigned Opcode) const {
675   if (STI.isOpenCLEnv() && I.getOperand(1).isReg()) {
676     Register SrcReg = I.getOperand(1).getReg();
677     bool IsGV = false;
678     for (MachineRegisterInfo::def_instr_iterator DefIt =
679              MRI->def_instr_begin(SrcReg);
680          DefIt != MRI->def_instr_end(); DefIt = std::next(DefIt)) {
681       if ((*DefIt).getOpcode() == TargetOpcode::G_GLOBAL_VALUE) {
682         IsGV = true;
683         break;
684       }
685     }
686     if (IsGV) {
687       uint32_t SpecOpcode = 0;
688       switch (Opcode) {
689       case SPIRV::OpConvertPtrToU:
690         SpecOpcode = static_cast<uint32_t>(SPIRV::Opcode::ConvertPtrToU);
691         break;
692       case SPIRV::OpConvertUToPtr:
693         SpecOpcode = static_cast<uint32_t>(SPIRV::Opcode::ConvertUToPtr);
694         break;
695       }
696       if (SpecOpcode)
697         return BuildMI(*I.getParent(), I, I.getDebugLoc(),
698                        TII.get(SPIRV::OpSpecConstantOp))
699             .addDef(ResVReg)
700             .addUse(GR.getSPIRVTypeID(ResType))
701             .addImm(SpecOpcode)
702             .addUse(SrcReg)
703             .constrainAllUses(TII, TRI, RBI);
704     }
705   }
706   return selectUnOpWithSrc(ResVReg, ResType, I, I.getOperand(1).getReg(),
707                            Opcode);
708 }
709 
710 bool SPIRVInstructionSelector::selectBitcast(Register ResVReg,
711                                              const SPIRVType *ResType,
712                                              MachineInstr &I) const {
713   Register OpReg = I.getOperand(1).getReg();
714   SPIRVType *OpType = OpReg.isValid() ? GR.getSPIRVTypeForVReg(OpReg) : nullptr;
715   if (!GR.isBitcastCompatible(ResType, OpType))
716     report_fatal_error("incompatible result and operand types in a bitcast");
717   return selectUnOp(ResVReg, ResType, I, SPIRV::OpBitcast);
718 }
719 
720 static SPIRV::Scope::Scope getScope(SyncScope::ID Ord,
721                                     SPIRVMachineModuleInfo *MMI) {
722   if (Ord == SyncScope::SingleThread || Ord == MMI->Work_ItemSSID)
723     return SPIRV::Scope::Invocation;
724   else if (Ord == SyncScope::System || Ord == MMI->DeviceSSID)
725     return SPIRV::Scope::Device;
726   else if (Ord == MMI->WorkGroupSSID)
727     return SPIRV::Scope::Workgroup;
728   else if (Ord == MMI->AllSVMDevicesSSID)
729     return SPIRV::Scope::CrossDevice;
730   else if (Ord == MMI->SubGroupSSID)
731     return SPIRV::Scope::Subgroup;
732   else
733     // OpenCL approach is: "The functions that do not have memory_scope argument
734     // have the same semantics as the corresponding functions with the
735     // memory_scope argument set to memory_scope_device." See ref.: //
736     // https://registry.khronos.org/OpenCL/specs/3.0-unified/html/OpenCL_C.html#atomic-functions
737     // In our case if the scope is unknown, assuming that SPIR-V code is to be
738     // consumed in an OpenCL environment, we use the same approach and set the
739     // scope to memory_scope_device.
740     return SPIRV::Scope::Device;
741 }
742 
743 static void addMemoryOperands(MachineMemOperand *MemOp,
744                               MachineInstrBuilder &MIB) {
745   uint32_t SpvMemOp = static_cast<uint32_t>(SPIRV::MemoryOperand::None);
746   if (MemOp->isVolatile())
747     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Volatile);
748   if (MemOp->isNonTemporal())
749     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Nontemporal);
750   if (MemOp->getAlign().value())
751     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Aligned);
752 
753   if (SpvMemOp != static_cast<uint32_t>(SPIRV::MemoryOperand::None)) {
754     MIB.addImm(SpvMemOp);
755     if (SpvMemOp & static_cast<uint32_t>(SPIRV::MemoryOperand::Aligned))
756       MIB.addImm(MemOp->getAlign().value());
757   }
758 }
759 
760 static void addMemoryOperands(uint64_t Flags, MachineInstrBuilder &MIB) {
761   uint32_t SpvMemOp = static_cast<uint32_t>(SPIRV::MemoryOperand::None);
762   if (Flags & MachineMemOperand::Flags::MOVolatile)
763     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Volatile);
764   if (Flags & MachineMemOperand::Flags::MONonTemporal)
765     SpvMemOp |= static_cast<uint32_t>(SPIRV::MemoryOperand::Nontemporal);
766 
767   if (SpvMemOp != static_cast<uint32_t>(SPIRV::MemoryOperand::None))
768     MIB.addImm(SpvMemOp);
769 }
770 
771 bool SPIRVInstructionSelector::selectLoad(Register ResVReg,
772                                           const SPIRVType *ResType,
773                                           MachineInstr &I) const {
774   unsigned OpOffset = isa<GIntrinsic>(I) ? 1 : 0;
775   Register Ptr = I.getOperand(1 + OpOffset).getReg();
776   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
777                  .addDef(ResVReg)
778                  .addUse(GR.getSPIRVTypeID(ResType))
779                  .addUse(Ptr);
780   if (!I.getNumMemOperands()) {
781     assert(I.getOpcode() == TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS ||
782            I.getOpcode() ==
783                TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS);
784     addMemoryOperands(I.getOperand(2 + OpOffset).getImm(), MIB);
785   } else {
786     addMemoryOperands(*I.memoperands_begin(), MIB);
787   }
788   return MIB.constrainAllUses(TII, TRI, RBI);
789 }
790 
791 bool SPIRVInstructionSelector::selectStore(MachineInstr &I) const {
792   unsigned OpOffset = isa<GIntrinsic>(I) ? 1 : 0;
793   Register StoreVal = I.getOperand(0 + OpOffset).getReg();
794   Register Ptr = I.getOperand(1 + OpOffset).getReg();
795   MachineBasicBlock &BB = *I.getParent();
796   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpStore))
797                  .addUse(Ptr)
798                  .addUse(StoreVal);
799   if (!I.getNumMemOperands()) {
800     assert(I.getOpcode() == TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS ||
801            I.getOpcode() ==
802                TargetOpcode::G_INTRINSIC_CONVERGENT_W_SIDE_EFFECTS);
803     addMemoryOperands(I.getOperand(2 + OpOffset).getImm(), MIB);
804   } else {
805     addMemoryOperands(*I.memoperands_begin(), MIB);
806   }
807   return MIB.constrainAllUses(TII, TRI, RBI);
808 }
809 
810 bool SPIRVInstructionSelector::selectStackSave(Register ResVReg,
811                                                const SPIRVType *ResType,
812                                                MachineInstr &I) const {
813   if (!STI.canUseExtension(SPIRV::Extension::SPV_INTEL_variable_length_array))
814     report_fatal_error(
815         "llvm.stacksave intrinsic: this instruction requires the following "
816         "SPIR-V extension: SPV_INTEL_variable_length_array",
817         false);
818   MachineBasicBlock &BB = *I.getParent();
819   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSaveMemoryINTEL))
820       .addDef(ResVReg)
821       .addUse(GR.getSPIRVTypeID(ResType))
822       .constrainAllUses(TII, TRI, RBI);
823 }
824 
825 bool SPIRVInstructionSelector::selectStackRestore(MachineInstr &I) const {
826   if (!STI.canUseExtension(SPIRV::Extension::SPV_INTEL_variable_length_array))
827     report_fatal_error(
828         "llvm.stackrestore intrinsic: this instruction requires the following "
829         "SPIR-V extension: SPV_INTEL_variable_length_array",
830         false);
831   if (!I.getOperand(0).isReg())
832     return false;
833   MachineBasicBlock &BB = *I.getParent();
834   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpRestoreMemoryINTEL))
835       .addUse(I.getOperand(0).getReg())
836       .constrainAllUses(TII, TRI, RBI);
837 }
838 
839 bool SPIRVInstructionSelector::selectMemOperation(Register ResVReg,
840                                                   MachineInstr &I) const {
841   MachineBasicBlock &BB = *I.getParent();
842   Register SrcReg = I.getOperand(1).getReg();
843   if (I.getOpcode() == TargetOpcode::G_MEMSET) {
844     assert(I.getOperand(1).isReg() && I.getOperand(2).isReg());
845     unsigned Val = getIConstVal(I.getOperand(1).getReg(), MRI);
846     unsigned Num = getIConstVal(I.getOperand(2).getReg(), MRI);
847     SPIRVType *ValTy = GR.getOrCreateSPIRVIntegerType(8, I, TII);
848     SPIRVType *ArrTy = GR.getOrCreateSPIRVArrayType(ValTy, Num, I, TII);
849     Register Const = GR.getOrCreateConsIntArray(Val, I, ArrTy, TII);
850     SPIRVType *VarTy = GR.getOrCreateSPIRVPointerType(
851         ArrTy, I, TII, SPIRV::StorageClass::UniformConstant);
852     // TODO: check if we have such GV, add init, use buildGlobalVariable.
853     Function &CurFunction = GR.CurMF->getFunction();
854     Type *LLVMArrTy =
855         ArrayType::get(IntegerType::get(CurFunction.getContext(), 8), Num);
856     // Module takes ownership of the global var.
857     GlobalVariable *GV = new GlobalVariable(*CurFunction.getParent(), LLVMArrTy,
858                                             true, GlobalValue::InternalLinkage,
859                                             Constant::getNullValue(LLVMArrTy));
860     Register VarReg = MRI->createGenericVirtualRegister(LLT::scalar(32));
861     GR.add(GV, GR.CurMF, VarReg);
862 
863     buildOpDecorate(VarReg, I, TII, SPIRV::Decoration::Constant, {});
864     BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpVariable))
865         .addDef(VarReg)
866         .addUse(GR.getSPIRVTypeID(VarTy))
867         .addImm(SPIRV::StorageClass::UniformConstant)
868         .addUse(Const)
869         .constrainAllUses(TII, TRI, RBI);
870     SPIRVType *SourceTy = GR.getOrCreateSPIRVPointerType(
871         ValTy, I, TII, SPIRV::StorageClass::UniformConstant);
872     SrcReg = MRI->createGenericVirtualRegister(LLT::scalar(32));
873     selectUnOpWithSrc(SrcReg, SourceTy, I, VarReg, SPIRV::OpBitcast);
874   }
875   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCopyMemorySized))
876                  .addUse(I.getOperand(0).getReg())
877                  .addUse(SrcReg)
878                  .addUse(I.getOperand(2).getReg());
879   if (I.getNumMemOperands())
880     addMemoryOperands(*I.memoperands_begin(), MIB);
881   bool Result = MIB.constrainAllUses(TII, TRI, RBI);
882   if (ResVReg.isValid() && ResVReg != MIB->getOperand(0).getReg())
883     BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY), ResVReg)
884         .addUse(MIB->getOperand(0).getReg());
885   return Result;
886 }
887 
888 bool SPIRVInstructionSelector::selectAtomicRMW(Register ResVReg,
889                                                const SPIRVType *ResType,
890                                                MachineInstr &I,
891                                                unsigned NewOpcode,
892                                                unsigned NegateOpcode) const {
893   assert(I.hasOneMemOperand());
894   const MachineMemOperand *MemOp = *I.memoperands_begin();
895   uint32_t Scope =
896       static_cast<uint32_t>(getScope(MemOp->getSyncScopeID(), MMI));
897   Register ScopeReg = buildI32Constant(Scope, I);
898 
899   Register Ptr = I.getOperand(1).getReg();
900   // TODO: Changed as it's implemented in the translator. See test/atomicrmw.ll
901   // auto ScSem =
902   // getMemSemanticsForStorageClass(GR.getPointerStorageClass(Ptr));
903   AtomicOrdering AO = MemOp->getSuccessOrdering();
904   uint32_t MemSem = static_cast<uint32_t>(getMemSemantics(AO));
905   Register MemSemReg = buildI32Constant(MemSem /*| ScSem*/, I);
906 
907   bool Result = false;
908   Register ValueReg = I.getOperand(2).getReg();
909   if (NegateOpcode != 0) {
910     // Translation with negative value operand is requested
911     Register TmpReg = MRI->createVirtualRegister(&SPIRV::IDRegClass);
912     Result |= selectUnOpWithSrc(TmpReg, ResType, I, ValueReg, NegateOpcode);
913     ValueReg = TmpReg;
914   }
915 
916   Result |= BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(NewOpcode))
917                 .addDef(ResVReg)
918                 .addUse(GR.getSPIRVTypeID(ResType))
919                 .addUse(Ptr)
920                 .addUse(ScopeReg)
921                 .addUse(MemSemReg)
922                 .addUse(ValueReg)
923                 .constrainAllUses(TII, TRI, RBI);
924   return Result;
925 }
926 
927 bool SPIRVInstructionSelector::selectUnmergeValues(MachineInstr &I) const {
928   unsigned ArgI = I.getNumOperands() - 1;
929   Register SrcReg =
930       I.getOperand(ArgI).isReg() ? I.getOperand(ArgI).getReg() : Register(0);
931   SPIRVType *DefType =
932       SrcReg.isValid() ? GR.getSPIRVTypeForVReg(SrcReg) : nullptr;
933   if (!DefType || DefType->getOpcode() != SPIRV::OpTypeVector)
934     report_fatal_error(
935         "cannot select G_UNMERGE_VALUES with a non-vector argument");
936 
937   SPIRVType *ScalarType =
938       GR.getSPIRVTypeForVReg(DefType->getOperand(1).getReg());
939   MachineBasicBlock &BB = *I.getParent();
940   bool Res = false;
941   for (unsigned i = 0; i < I.getNumDefs(); ++i) {
942     Register ResVReg = I.getOperand(i).getReg();
943     SPIRVType *ResType = GR.getSPIRVTypeForVReg(ResVReg);
944     if (!ResType) {
945       // There was no "assign type" actions, let's fix this now
946       ResType = ScalarType;
947       MRI->setRegClass(ResVReg, &SPIRV::IDRegClass);
948       MRI->setType(ResVReg, LLT::scalar(GR.getScalarOrVectorBitWidth(ResType)));
949       GR.assignSPIRVTypeToVReg(ResType, ResVReg, *GR.CurMF);
950     }
951     auto MIB =
952         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
953             .addDef(ResVReg)
954             .addUse(GR.getSPIRVTypeID(ResType))
955             .addUse(SrcReg)
956             .addImm(static_cast<int64_t>(i));
957     Res |= MIB.constrainAllUses(TII, TRI, RBI);
958   }
959   return Res;
960 }
961 
962 bool SPIRVInstructionSelector::selectFence(MachineInstr &I) const {
963   AtomicOrdering AO = AtomicOrdering(I.getOperand(0).getImm());
964   uint32_t MemSem = static_cast<uint32_t>(getMemSemantics(AO));
965   Register MemSemReg = buildI32Constant(MemSem, I);
966   SyncScope::ID Ord = SyncScope::ID(I.getOperand(1).getImm());
967   uint32_t Scope = static_cast<uint32_t>(getScope(Ord, MMI));
968   Register ScopeReg = buildI32Constant(Scope, I);
969   MachineBasicBlock &BB = *I.getParent();
970   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpMemoryBarrier))
971       .addUse(ScopeReg)
972       .addUse(MemSemReg)
973       .constrainAllUses(TII, TRI, RBI);
974 }
975 
976 bool SPIRVInstructionSelector::selectAtomicCmpXchg(Register ResVReg,
977                                                    const SPIRVType *ResType,
978                                                    MachineInstr &I) const {
979   Register ScopeReg;
980   Register MemSemEqReg;
981   Register MemSemNeqReg;
982   Register Ptr = I.getOperand(2).getReg();
983   if (!isa<GIntrinsic>(I)) {
984     assert(I.hasOneMemOperand());
985     const MachineMemOperand *MemOp = *I.memoperands_begin();
986     unsigned Scope =
987         static_cast<uint32_t>(getScope(MemOp->getSyncScopeID(), MMI));
988     ScopeReg = buildI32Constant(Scope, I);
989 
990     unsigned ScSem = static_cast<uint32_t>(
991         getMemSemanticsForStorageClass(GR.getPointerStorageClass(Ptr)));
992     AtomicOrdering AO = MemOp->getSuccessOrdering();
993     unsigned MemSemEq = static_cast<uint32_t>(getMemSemantics(AO)) | ScSem;
994     MemSemEqReg = buildI32Constant(MemSemEq, I);
995     AtomicOrdering FO = MemOp->getFailureOrdering();
996     unsigned MemSemNeq = static_cast<uint32_t>(getMemSemantics(FO)) | ScSem;
997     MemSemNeqReg =
998         MemSemEq == MemSemNeq ? MemSemEqReg : buildI32Constant(MemSemNeq, I);
999   } else {
1000     ScopeReg = I.getOperand(5).getReg();
1001     MemSemEqReg = I.getOperand(6).getReg();
1002     MemSemNeqReg = I.getOperand(7).getReg();
1003   }
1004 
1005   Register Cmp = I.getOperand(3).getReg();
1006   Register Val = I.getOperand(4).getReg();
1007   SPIRVType *SpvValTy = GR.getSPIRVTypeForVReg(Val);
1008   Register ACmpRes = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1009   const DebugLoc &DL = I.getDebugLoc();
1010   bool Result =
1011       BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpAtomicCompareExchange))
1012           .addDef(ACmpRes)
1013           .addUse(GR.getSPIRVTypeID(SpvValTy))
1014           .addUse(Ptr)
1015           .addUse(ScopeReg)
1016           .addUse(MemSemEqReg)
1017           .addUse(MemSemNeqReg)
1018           .addUse(Val)
1019           .addUse(Cmp)
1020           .constrainAllUses(TII, TRI, RBI);
1021   Register CmpSuccReg = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1022   SPIRVType *BoolTy = GR.getOrCreateSPIRVBoolType(I, TII);
1023   Result |= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpIEqual))
1024                 .addDef(CmpSuccReg)
1025                 .addUse(GR.getSPIRVTypeID(BoolTy))
1026                 .addUse(ACmpRes)
1027                 .addUse(Cmp)
1028                 .constrainAllUses(TII, TRI, RBI);
1029   Register TmpReg = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1030   Result |= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpCompositeInsert))
1031                 .addDef(TmpReg)
1032                 .addUse(GR.getSPIRVTypeID(ResType))
1033                 .addUse(ACmpRes)
1034                 .addUse(GR.getOrCreateUndef(I, ResType, TII))
1035                 .addImm(0)
1036                 .constrainAllUses(TII, TRI, RBI);
1037   Result |= BuildMI(*I.getParent(), I, DL, TII.get(SPIRV::OpCompositeInsert))
1038                 .addDef(ResVReg)
1039                 .addUse(GR.getSPIRVTypeID(ResType))
1040                 .addUse(CmpSuccReg)
1041                 .addUse(TmpReg)
1042                 .addImm(1)
1043                 .constrainAllUses(TII, TRI, RBI);
1044   return Result;
1045 }
1046 
1047 static bool isGenericCastablePtr(SPIRV::StorageClass::StorageClass SC) {
1048   switch (SC) {
1049   case SPIRV::StorageClass::Workgroup:
1050   case SPIRV::StorageClass::CrossWorkgroup:
1051   case SPIRV::StorageClass::Function:
1052     return true;
1053   default:
1054     return false;
1055   }
1056 }
1057 
1058 static bool isUSMStorageClass(SPIRV::StorageClass::StorageClass SC) {
1059   switch (SC) {
1060   case SPIRV::StorageClass::DeviceOnlyINTEL:
1061   case SPIRV::StorageClass::HostOnlyINTEL:
1062     return true;
1063   default:
1064     return false;
1065   }
1066 }
1067 
1068 // In SPIR-V address space casting can only happen to and from the Generic
1069 // storage class. We can also only cast Workgroup, CrossWorkgroup, or Function
1070 // pointers to and from Generic pointers. As such, we can convert e.g. from
1071 // Workgroup to Function by going via a Generic pointer as an intermediary. All
1072 // other combinations can only be done by a bitcast, and are probably not safe.
1073 bool SPIRVInstructionSelector::selectAddrSpaceCast(Register ResVReg,
1074                                                    const SPIRVType *ResType,
1075                                                    MachineInstr &I) const {
1076   // If the AddrSpaceCast user is single and in OpConstantComposite or
1077   // OpVariable, we should select OpSpecConstantOp.
1078   auto UIs = MRI->use_instructions(ResVReg);
1079   if (!UIs.empty() && ++UIs.begin() == UIs.end() &&
1080       (UIs.begin()->getOpcode() == SPIRV::OpConstantComposite ||
1081        UIs.begin()->getOpcode() == SPIRV::OpVariable ||
1082        isSpvIntrinsic(*UIs.begin(), Intrinsic::spv_init_global))) {
1083     Register NewReg = I.getOperand(1).getReg();
1084     MachineBasicBlock &BB = *I.getParent();
1085     SPIRVType *SpvBaseTy = GR.getOrCreateSPIRVIntegerType(8, I, TII);
1086     ResType = GR.getOrCreateSPIRVPointerType(SpvBaseTy, I, TII,
1087                                              SPIRV::StorageClass::Generic);
1088     bool Result =
1089         BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
1090             .addDef(ResVReg)
1091             .addUse(GR.getSPIRVTypeID(ResType))
1092             .addImm(static_cast<uint32_t>(SPIRV::Opcode::PtrCastToGeneric))
1093             .addUse(NewReg)
1094             .constrainAllUses(TII, TRI, RBI);
1095     return Result;
1096   }
1097   Register SrcPtr = I.getOperand(1).getReg();
1098   SPIRVType *SrcPtrTy = GR.getSPIRVTypeForVReg(SrcPtr);
1099   SPIRV::StorageClass::StorageClass SrcSC = GR.getPointerStorageClass(SrcPtr);
1100   SPIRV::StorageClass::StorageClass DstSC = GR.getPointerStorageClass(ResVReg);
1101 
1102   // don't generate a cast between identical storage classes
1103   if (SrcSC == DstSC)
1104     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1105                    TII.get(TargetOpcode::COPY))
1106         .addDef(ResVReg)
1107         .addUse(SrcPtr)
1108         .constrainAllUses(TII, TRI, RBI);
1109 
1110   // Casting from an eligible pointer to Generic.
1111   if (DstSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(SrcSC))
1112     return selectUnOp(ResVReg, ResType, I, SPIRV::OpPtrCastToGeneric);
1113   // Casting from Generic to an eligible pointer.
1114   if (SrcSC == SPIRV::StorageClass::Generic && isGenericCastablePtr(DstSC))
1115     return selectUnOp(ResVReg, ResType, I, SPIRV::OpGenericCastToPtr);
1116   // Casting between 2 eligible pointers using Generic as an intermediary.
1117   if (isGenericCastablePtr(SrcSC) && isGenericCastablePtr(DstSC)) {
1118     Register Tmp = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1119     SPIRVType *GenericPtrTy = GR.getOrCreateSPIRVPointerType(
1120         GR.getPointeeType(SrcPtrTy), I, TII, SPIRV::StorageClass::Generic);
1121     MachineBasicBlock &BB = *I.getParent();
1122     const DebugLoc &DL = I.getDebugLoc();
1123     bool Success = BuildMI(BB, I, DL, TII.get(SPIRV::OpPtrCastToGeneric))
1124                        .addDef(Tmp)
1125                        .addUse(GR.getSPIRVTypeID(GenericPtrTy))
1126                        .addUse(SrcPtr)
1127                        .constrainAllUses(TII, TRI, RBI);
1128     return Success && BuildMI(BB, I, DL, TII.get(SPIRV::OpGenericCastToPtr))
1129                           .addDef(ResVReg)
1130                           .addUse(GR.getSPIRVTypeID(ResType))
1131                           .addUse(Tmp)
1132                           .constrainAllUses(TII, TRI, RBI);
1133   }
1134 
1135   // Check if instructions from the SPV_INTEL_usm_storage_classes extension may
1136   // be applied
1137   if (isUSMStorageClass(SrcSC) && DstSC == SPIRV::StorageClass::CrossWorkgroup)
1138     return selectUnOp(ResVReg, ResType, I,
1139                       SPIRV::OpPtrCastToCrossWorkgroupINTEL);
1140   if (SrcSC == SPIRV::StorageClass::CrossWorkgroup && isUSMStorageClass(DstSC))
1141     return selectUnOp(ResVReg, ResType, I,
1142                       SPIRV::OpCrossWorkgroupCastToPtrINTEL);
1143   if (isUSMStorageClass(SrcSC) && DstSC == SPIRV::StorageClass::Generic)
1144     return selectUnOp(ResVReg, ResType, I, SPIRV::OpPtrCastToGeneric);
1145   if (SrcSC == SPIRV::StorageClass::Generic && isUSMStorageClass(DstSC))
1146     return selectUnOp(ResVReg, ResType, I, SPIRV::OpGenericCastToPtr);
1147 
1148   // Bitcast for pointers requires that the address spaces must match
1149   return false;
1150 }
1151 
1152 static unsigned getFCmpOpcode(unsigned PredNum) {
1153   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1154   switch (Pred) {
1155   case CmpInst::FCMP_OEQ:
1156     return SPIRV::OpFOrdEqual;
1157   case CmpInst::FCMP_OGE:
1158     return SPIRV::OpFOrdGreaterThanEqual;
1159   case CmpInst::FCMP_OGT:
1160     return SPIRV::OpFOrdGreaterThan;
1161   case CmpInst::FCMP_OLE:
1162     return SPIRV::OpFOrdLessThanEqual;
1163   case CmpInst::FCMP_OLT:
1164     return SPIRV::OpFOrdLessThan;
1165   case CmpInst::FCMP_ONE:
1166     return SPIRV::OpFOrdNotEqual;
1167   case CmpInst::FCMP_ORD:
1168     return SPIRV::OpOrdered;
1169   case CmpInst::FCMP_UEQ:
1170     return SPIRV::OpFUnordEqual;
1171   case CmpInst::FCMP_UGE:
1172     return SPIRV::OpFUnordGreaterThanEqual;
1173   case CmpInst::FCMP_UGT:
1174     return SPIRV::OpFUnordGreaterThan;
1175   case CmpInst::FCMP_ULE:
1176     return SPIRV::OpFUnordLessThanEqual;
1177   case CmpInst::FCMP_ULT:
1178     return SPIRV::OpFUnordLessThan;
1179   case CmpInst::FCMP_UNE:
1180     return SPIRV::OpFUnordNotEqual;
1181   case CmpInst::FCMP_UNO:
1182     return SPIRV::OpUnordered;
1183   default:
1184     llvm_unreachable("Unknown predicate type for FCmp");
1185   }
1186 }
1187 
1188 static unsigned getICmpOpcode(unsigned PredNum) {
1189   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1190   switch (Pred) {
1191   case CmpInst::ICMP_EQ:
1192     return SPIRV::OpIEqual;
1193   case CmpInst::ICMP_NE:
1194     return SPIRV::OpINotEqual;
1195   case CmpInst::ICMP_SGE:
1196     return SPIRV::OpSGreaterThanEqual;
1197   case CmpInst::ICMP_SGT:
1198     return SPIRV::OpSGreaterThan;
1199   case CmpInst::ICMP_SLE:
1200     return SPIRV::OpSLessThanEqual;
1201   case CmpInst::ICMP_SLT:
1202     return SPIRV::OpSLessThan;
1203   case CmpInst::ICMP_UGE:
1204     return SPIRV::OpUGreaterThanEqual;
1205   case CmpInst::ICMP_UGT:
1206     return SPIRV::OpUGreaterThan;
1207   case CmpInst::ICMP_ULE:
1208     return SPIRV::OpULessThanEqual;
1209   case CmpInst::ICMP_ULT:
1210     return SPIRV::OpULessThan;
1211   default:
1212     llvm_unreachable("Unknown predicate type for ICmp");
1213   }
1214 }
1215 
1216 static unsigned getPtrCmpOpcode(unsigned Pred) {
1217   switch (static_cast<CmpInst::Predicate>(Pred)) {
1218   case CmpInst::ICMP_EQ:
1219     return SPIRV::OpPtrEqual;
1220   case CmpInst::ICMP_NE:
1221     return SPIRV::OpPtrNotEqual;
1222   default:
1223     llvm_unreachable("Unknown predicate type for pointer comparison");
1224   }
1225 }
1226 
1227 // Return the logical operation, or abort if none exists.
1228 static unsigned getBoolCmpOpcode(unsigned PredNum) {
1229   auto Pred = static_cast<CmpInst::Predicate>(PredNum);
1230   switch (Pred) {
1231   case CmpInst::ICMP_EQ:
1232     return SPIRV::OpLogicalEqual;
1233   case CmpInst::ICMP_NE:
1234     return SPIRV::OpLogicalNotEqual;
1235   default:
1236     llvm_unreachable("Unknown predicate type for Bool comparison");
1237   }
1238 }
1239 
1240 bool SPIRVInstructionSelector::selectAnyOrAll(Register ResVReg,
1241                                               const SPIRVType *ResType,
1242                                               MachineInstr &I,
1243                                               unsigned OpAnyOrAll) const {
1244   assert(I.getNumOperands() == 3);
1245   assert(I.getOperand(2).isReg());
1246   MachineBasicBlock &BB = *I.getParent();
1247   Register InputRegister = I.getOperand(2).getReg();
1248   SPIRVType *InputType = GR.getSPIRVTypeForVReg(InputRegister);
1249 
1250   if (!InputType)
1251     report_fatal_error("Input Type could not be determined.");
1252 
1253   bool IsBoolTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeBool);
1254   bool IsVectorTy = InputType->getOpcode() == SPIRV::OpTypeVector;
1255   if (IsBoolTy && !IsVectorTy) {
1256     assert(ResVReg == I.getOperand(0).getReg());
1257     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1258                    TII.get(TargetOpcode::COPY))
1259         .addDef(ResVReg)
1260         .addUse(InputRegister)
1261         .constrainAllUses(TII, TRI, RBI);
1262   }
1263 
1264   bool IsFloatTy = GR.isScalarOrVectorOfType(InputRegister, SPIRV::OpTypeFloat);
1265   unsigned SpirvNotEqualId =
1266       IsFloatTy ? SPIRV::OpFOrdNotEqual : SPIRV::OpINotEqual;
1267   SPIRVType *SpvBoolScalarTy = GR.getOrCreateSPIRVBoolType(I, TII);
1268   SPIRVType *SpvBoolTy = SpvBoolScalarTy;
1269   Register NotEqualReg = ResVReg;
1270 
1271   if (IsVectorTy) {
1272     NotEqualReg = IsBoolTy ? InputRegister
1273                            : MRI->createVirtualRegister(&SPIRV::IDRegClass);
1274     const unsigned NumElts = InputType->getOperand(2).getImm();
1275     SpvBoolTy = GR.getOrCreateSPIRVVectorType(SpvBoolTy, NumElts, I, TII);
1276   }
1277 
1278   if (!IsBoolTy) {
1279     Register ConstZeroReg =
1280         IsFloatTy ? buildZerosValF(InputType, I) : buildZerosVal(InputType, I);
1281 
1282     BuildMI(BB, I, I.getDebugLoc(), TII.get(SpirvNotEqualId))
1283         .addDef(NotEqualReg)
1284         .addUse(GR.getSPIRVTypeID(SpvBoolTy))
1285         .addUse(InputRegister)
1286         .addUse(ConstZeroReg)
1287         .constrainAllUses(TII, TRI, RBI);
1288   }
1289 
1290   if (!IsVectorTy)
1291     return true;
1292 
1293   return BuildMI(BB, I, I.getDebugLoc(), TII.get(OpAnyOrAll))
1294       .addDef(ResVReg)
1295       .addUse(GR.getSPIRVTypeID(SpvBoolScalarTy))
1296       .addUse(NotEqualReg)
1297       .constrainAllUses(TII, TRI, RBI);
1298 }
1299 
1300 bool SPIRVInstructionSelector::selectAll(Register ResVReg,
1301                                          const SPIRVType *ResType,
1302                                          MachineInstr &I) const {
1303   return selectAnyOrAll(ResVReg, ResType, I, SPIRV::OpAll);
1304 }
1305 
1306 bool SPIRVInstructionSelector::selectAny(Register ResVReg,
1307                                          const SPIRVType *ResType,
1308                                          MachineInstr &I) const {
1309   return selectAnyOrAll(ResVReg, ResType, I, SPIRV::OpAny);
1310 }
1311 
1312 bool SPIRVInstructionSelector::selectFmix(Register ResVReg,
1313                                           const SPIRVType *ResType,
1314                                           MachineInstr &I) const {
1315 
1316   assert(I.getNumOperands() == 5);
1317   assert(I.getOperand(2).isReg());
1318   assert(I.getOperand(3).isReg());
1319   assert(I.getOperand(4).isReg());
1320   MachineBasicBlock &BB = *I.getParent();
1321 
1322   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
1323       .addDef(ResVReg)
1324       .addUse(GR.getSPIRVTypeID(ResType))
1325       .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
1326       .addImm(GL::FMix)
1327       .addUse(I.getOperand(2).getReg())
1328       .addUse(I.getOperand(3).getReg())
1329       .addUse(I.getOperand(4).getReg())
1330       .constrainAllUses(TII, TRI, RBI);
1331 }
1332 
1333 bool SPIRVInstructionSelector::selectRsqrt(Register ResVReg,
1334                                            const SPIRVType *ResType,
1335                                            MachineInstr &I) const {
1336 
1337   assert(I.getNumOperands() == 3);
1338   assert(I.getOperand(2).isReg());
1339   MachineBasicBlock &BB = *I.getParent();
1340 
1341   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
1342       .addDef(ResVReg)
1343       .addUse(GR.getSPIRVTypeID(ResType))
1344       .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
1345       .addImm(GL::InverseSqrt)
1346       .addUse(I.getOperand(2).getReg())
1347       .constrainAllUses(TII, TRI, RBI);
1348 }
1349 
1350 bool SPIRVInstructionSelector::selectBitreverse(Register ResVReg,
1351                                                 const SPIRVType *ResType,
1352                                                 MachineInstr &I) const {
1353   MachineBasicBlock &BB = *I.getParent();
1354   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpBitReverse))
1355       .addDef(ResVReg)
1356       .addUse(GR.getSPIRVTypeID(ResType))
1357       .addUse(I.getOperand(1).getReg())
1358       .constrainAllUses(TII, TRI, RBI);
1359 }
1360 
1361 bool SPIRVInstructionSelector::selectFreeze(Register ResVReg,
1362                                             const SPIRVType *ResType,
1363                                             MachineInstr &I) const {
1364   // There is no way to implement `freeze` correctly without support on SPIR-V
1365   // standard side, but we may at least address a simple (static) case when
1366   // undef/poison value presence is obvious. The main benefit of even
1367   // incomplete `freeze` support is preventing of translation from crashing due
1368   // to lack of support on legalization and instruction selection steps.
1369   if (!I.getOperand(0).isReg() || !I.getOperand(1).isReg())
1370     return false;
1371   Register OpReg = I.getOperand(1).getReg();
1372   if (MachineInstr *Def = MRI->getVRegDef(OpReg)) {
1373     Register Reg;
1374     switch (Def->getOpcode()) {
1375     case SPIRV::ASSIGN_TYPE:
1376       if (MachineInstr *AssignToDef =
1377               MRI->getVRegDef(Def->getOperand(1).getReg())) {
1378         if (AssignToDef->getOpcode() == TargetOpcode::G_IMPLICIT_DEF)
1379           Reg = Def->getOperand(2).getReg();
1380       }
1381       break;
1382     case SPIRV::OpUndef:
1383       Reg = Def->getOperand(1).getReg();
1384       break;
1385     }
1386     unsigned DestOpCode;
1387     if (Reg.isValid()) {
1388       DestOpCode = SPIRV::OpConstantNull;
1389     } else {
1390       DestOpCode = TargetOpcode::COPY;
1391       Reg = OpReg;
1392     }
1393     return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(DestOpCode))
1394         .addDef(I.getOperand(0).getReg())
1395         .addUse(Reg)
1396         .constrainAllUses(TII, TRI, RBI);
1397   }
1398   return false;
1399 }
1400 
1401 bool SPIRVInstructionSelector::selectConstVector(Register ResVReg,
1402                                                  const SPIRVType *ResType,
1403                                                  MachineInstr &I) const {
1404   // TODO: only const case is supported for now.
1405   assert(std::all_of(
1406       I.operands_begin(), I.operands_end(), [this](const MachineOperand &MO) {
1407         if (MO.isDef())
1408           return true;
1409         if (!MO.isReg())
1410           return false;
1411         SPIRVType *ConstTy = this->MRI->getVRegDef(MO.getReg());
1412         assert(ConstTy && ConstTy->getOpcode() == SPIRV::ASSIGN_TYPE &&
1413                ConstTy->getOperand(1).isReg());
1414         Register ConstReg = ConstTy->getOperand(1).getReg();
1415         const MachineInstr *Const = this->MRI->getVRegDef(ConstReg);
1416         assert(Const);
1417         return (Const->getOpcode() == TargetOpcode::G_CONSTANT ||
1418                 Const->getOpcode() == TargetOpcode::G_FCONSTANT);
1419       }));
1420 
1421   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
1422                      TII.get(SPIRV::OpConstantComposite))
1423                  .addDef(ResVReg)
1424                  .addUse(GR.getSPIRVTypeID(ResType));
1425   for (unsigned i = I.getNumExplicitDefs(); i < I.getNumExplicitOperands(); ++i)
1426     MIB.addUse(I.getOperand(i).getReg());
1427   return MIB.constrainAllUses(TII, TRI, RBI);
1428 }
1429 
1430 static unsigned getArrayComponentCount(MachineRegisterInfo *MRI,
1431                                        const SPIRVType *ResType) {
1432   Register OpReg = ResType->getOperand(2).getReg();
1433   SPIRVType *OpDef = MRI->getVRegDef(OpReg);
1434   if (!OpDef)
1435     return 0;
1436   if (OpDef->getOpcode() == SPIRV::ASSIGN_TYPE &&
1437       OpDef->getOperand(1).isReg()) {
1438     if (SPIRVType *RefDef = MRI->getVRegDef(OpDef->getOperand(1).getReg()))
1439       OpDef = RefDef;
1440   }
1441   unsigned N = OpDef->getOpcode() == TargetOpcode::G_CONSTANT
1442                    ? OpDef->getOperand(1).getCImm()->getValue().getZExtValue()
1443                    : 0;
1444   return N;
1445 }
1446 
1447 // Return true if the type represents a constant register
1448 static bool isConstReg(MachineRegisterInfo *MRI, SPIRVType *OpDef) {
1449   if (OpDef->getOpcode() == SPIRV::ASSIGN_TYPE &&
1450       OpDef->getOperand(1).isReg()) {
1451     if (SPIRVType *RefDef = MRI->getVRegDef(OpDef->getOperand(1).getReg()))
1452       OpDef = RefDef;
1453   }
1454   return OpDef->getOpcode() == TargetOpcode::G_CONSTANT ||
1455          OpDef->getOpcode() == TargetOpcode::G_FCONSTANT;
1456 }
1457 
1458 // Return true if the virtual register represents a constant
1459 static bool isConstReg(MachineRegisterInfo *MRI, Register OpReg) {
1460   if (SPIRVType *OpDef = MRI->getVRegDef(OpReg))
1461     return isConstReg(MRI, OpDef);
1462   return false;
1463 }
1464 
1465 bool SPIRVInstructionSelector::selectSplatVector(Register ResVReg,
1466                                                  const SPIRVType *ResType,
1467                                                  MachineInstr &I) const {
1468   unsigned N = 0;
1469   if (ResType->getOpcode() == SPIRV::OpTypeVector)
1470     N = GR.getScalarOrVectorComponentCount(ResType);
1471   else if (ResType->getOpcode() == SPIRV::OpTypeArray)
1472     N = getArrayComponentCount(MRI, ResType);
1473   else
1474     report_fatal_error("Cannot select G_SPLAT_VECTOR with a non-vector result");
1475 
1476   unsigned OpIdx = I.getNumExplicitDefs();
1477   if (!I.getOperand(OpIdx).isReg())
1478     report_fatal_error("Unexpected argument in G_SPLAT_VECTOR");
1479 
1480   // check if we may construct a constant vector
1481   Register OpReg = I.getOperand(OpIdx).getReg();
1482   bool IsConst = isConstReg(MRI, OpReg);
1483 
1484   if (!IsConst && N < 2)
1485     report_fatal_error(
1486         "There must be at least two constituent operands in a vector");
1487 
1488   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(),
1489                      TII.get(IsConst ? SPIRV::OpConstantComposite
1490                                      : SPIRV::OpCompositeConstruct))
1491                  .addDef(ResVReg)
1492                  .addUse(GR.getSPIRVTypeID(ResType));
1493   for (unsigned i = 0; i < N; ++i)
1494     MIB.addUse(OpReg);
1495   return MIB.constrainAllUses(TII, TRI, RBI);
1496 }
1497 
1498 bool SPIRVInstructionSelector::selectCmp(Register ResVReg,
1499                                          const SPIRVType *ResType,
1500                                          unsigned CmpOpc,
1501                                          MachineInstr &I) const {
1502   Register Cmp0 = I.getOperand(2).getReg();
1503   Register Cmp1 = I.getOperand(3).getReg();
1504   assert(GR.getSPIRVTypeForVReg(Cmp0)->getOpcode() ==
1505              GR.getSPIRVTypeForVReg(Cmp1)->getOpcode() &&
1506          "CMP operands should have the same type");
1507   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(CmpOpc))
1508       .addDef(ResVReg)
1509       .addUse(GR.getSPIRVTypeID(ResType))
1510       .addUse(Cmp0)
1511       .addUse(Cmp1)
1512       .constrainAllUses(TII, TRI, RBI);
1513 }
1514 
1515 bool SPIRVInstructionSelector::selectICmp(Register ResVReg,
1516                                           const SPIRVType *ResType,
1517                                           MachineInstr &I) const {
1518   auto Pred = I.getOperand(1).getPredicate();
1519   unsigned CmpOpc;
1520 
1521   Register CmpOperand = I.getOperand(2).getReg();
1522   if (GR.isScalarOfType(CmpOperand, SPIRV::OpTypePointer))
1523     CmpOpc = getPtrCmpOpcode(Pred);
1524   else if (GR.isScalarOrVectorOfType(CmpOperand, SPIRV::OpTypeBool))
1525     CmpOpc = getBoolCmpOpcode(Pred);
1526   else
1527     CmpOpc = getICmpOpcode(Pred);
1528   return selectCmp(ResVReg, ResType, CmpOpc, I);
1529 }
1530 
1531 void SPIRVInstructionSelector::renderFImm32(MachineInstrBuilder &MIB,
1532                                             const MachineInstr &I,
1533                                             int OpIdx) const {
1534   assert(I.getOpcode() == TargetOpcode::G_FCONSTANT && OpIdx == -1 &&
1535          "Expected G_FCONSTANT");
1536   const ConstantFP *FPImm = I.getOperand(1).getFPImm();
1537   addNumImm(FPImm->getValueAPF().bitcastToAPInt(), MIB);
1538 }
1539 
1540 void SPIRVInstructionSelector::renderImm32(MachineInstrBuilder &MIB,
1541                                            const MachineInstr &I,
1542                                            int OpIdx) const {
1543   assert(I.getOpcode() == TargetOpcode::G_CONSTANT && OpIdx == -1 &&
1544          "Expected G_CONSTANT");
1545   addNumImm(I.getOperand(1).getCImm()->getValue(), MIB);
1546 }
1547 
1548 Register
1549 SPIRVInstructionSelector::buildI32Constant(uint32_t Val, MachineInstr &I,
1550                                            const SPIRVType *ResType) const {
1551   Type *LLVMTy = IntegerType::get(GR.CurMF->getFunction().getContext(), 32);
1552   const SPIRVType *SpvI32Ty =
1553       ResType ? ResType : GR.getOrCreateSPIRVIntegerType(32, I, TII);
1554   // Find a constant in DT or build a new one.
1555   auto ConstInt = ConstantInt::get(LLVMTy, Val);
1556   Register NewReg = GR.find(ConstInt, GR.CurMF);
1557   if (!NewReg.isValid()) {
1558     NewReg = MRI->createGenericVirtualRegister(LLT::scalar(32));
1559     GR.add(ConstInt, GR.CurMF, NewReg);
1560     MachineInstr *MI;
1561     MachineBasicBlock &BB = *I.getParent();
1562     if (Val == 0) {
1563       MI = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
1564                .addDef(NewReg)
1565                .addUse(GR.getSPIRVTypeID(SpvI32Ty));
1566     } else {
1567       MI = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantI))
1568                .addDef(NewReg)
1569                .addUse(GR.getSPIRVTypeID(SpvI32Ty))
1570                .addImm(APInt(32, Val).getZExtValue());
1571     }
1572     constrainSelectedInstRegOperands(*MI, TII, TRI, RBI);
1573   }
1574   return NewReg;
1575 }
1576 
1577 bool SPIRVInstructionSelector::selectFCmp(Register ResVReg,
1578                                           const SPIRVType *ResType,
1579                                           MachineInstr &I) const {
1580   unsigned CmpOp = getFCmpOpcode(I.getOperand(1).getPredicate());
1581   return selectCmp(ResVReg, ResType, CmpOp, I);
1582 }
1583 
1584 Register SPIRVInstructionSelector::buildZerosVal(const SPIRVType *ResType,
1585                                                  MachineInstr &I) const {
1586   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
1587   bool ZeroAsNull = STI.isOpenCLEnv();
1588   if (ResType->getOpcode() == SPIRV::OpTypeVector)
1589     return GR.getOrCreateConstVector(0UL, I, ResType, TII, ZeroAsNull);
1590   return GR.getOrCreateConstInt(0, I, ResType, TII, ZeroAsNull);
1591 }
1592 
1593 static APFloat getZeroFP(const Type *LLVMFloatTy) {
1594   if (!LLVMFloatTy)
1595     return APFloat::getZero(APFloat::IEEEsingle());
1596   switch (LLVMFloatTy->getScalarType()->getTypeID()) {
1597   case Type::HalfTyID:
1598     return APFloat::getZero(APFloat::IEEEhalf());
1599   default:
1600   case Type::FloatTyID:
1601     return APFloat::getZero(APFloat::IEEEsingle());
1602   case Type::DoubleTyID:
1603     return APFloat::getZero(APFloat::IEEEdouble());
1604   }
1605 }
1606 
1607 Register SPIRVInstructionSelector::buildZerosValF(const SPIRVType *ResType,
1608                                                   MachineInstr &I) const {
1609   // OpenCL uses nulls for Zero. In HLSL we don't use null constants.
1610   bool ZeroAsNull = STI.isOpenCLEnv();
1611   APFloat VZero = getZeroFP(GR.getTypeForSPIRVType(ResType));
1612   if (ResType->getOpcode() == SPIRV::OpTypeVector)
1613     return GR.getOrCreateConstVector(VZero, I, ResType, TII, ZeroAsNull);
1614   return GR.getOrCreateConstFP(VZero, I, ResType, TII, ZeroAsNull);
1615 }
1616 
1617 Register SPIRVInstructionSelector::buildOnesVal(bool AllOnes,
1618                                                 const SPIRVType *ResType,
1619                                                 MachineInstr &I) const {
1620   unsigned BitWidth = GR.getScalarOrVectorBitWidth(ResType);
1621   APInt One =
1622       AllOnes ? APInt::getAllOnes(BitWidth) : APInt::getOneBitSet(BitWidth, 0);
1623   if (ResType->getOpcode() == SPIRV::OpTypeVector)
1624     return GR.getOrCreateConstVector(One.getZExtValue(), I, ResType, TII);
1625   return GR.getOrCreateConstInt(One.getZExtValue(), I, ResType, TII);
1626 }
1627 
1628 bool SPIRVInstructionSelector::selectSelect(Register ResVReg,
1629                                             const SPIRVType *ResType,
1630                                             MachineInstr &I,
1631                                             bool IsSigned) const {
1632   // To extend a bool, we need to use OpSelect between constants.
1633   Register ZeroReg = buildZerosVal(ResType, I);
1634   Register OneReg = buildOnesVal(IsSigned, ResType, I);
1635   bool IsScalarBool =
1636       GR.isScalarOfType(I.getOperand(1).getReg(), SPIRV::OpTypeBool);
1637   unsigned Opcode =
1638       IsScalarBool ? SPIRV::OpSelectSISCond : SPIRV::OpSelectSIVCond;
1639   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
1640       .addDef(ResVReg)
1641       .addUse(GR.getSPIRVTypeID(ResType))
1642       .addUse(I.getOperand(1).getReg())
1643       .addUse(OneReg)
1644       .addUse(ZeroReg)
1645       .constrainAllUses(TII, TRI, RBI);
1646 }
1647 
1648 bool SPIRVInstructionSelector::selectIToF(Register ResVReg,
1649                                           const SPIRVType *ResType,
1650                                           MachineInstr &I, bool IsSigned,
1651                                           unsigned Opcode) const {
1652   Register SrcReg = I.getOperand(1).getReg();
1653   // We can convert bool value directly to float type without OpConvert*ToF,
1654   // however the translator generates OpSelect+OpConvert*ToF, so we do the same.
1655   if (GR.isScalarOrVectorOfType(I.getOperand(1).getReg(), SPIRV::OpTypeBool)) {
1656     unsigned BitWidth = GR.getScalarOrVectorBitWidth(ResType);
1657     SPIRVType *TmpType = GR.getOrCreateSPIRVIntegerType(BitWidth, I, TII);
1658     if (ResType->getOpcode() == SPIRV::OpTypeVector) {
1659       const unsigned NumElts = ResType->getOperand(2).getImm();
1660       TmpType = GR.getOrCreateSPIRVVectorType(TmpType, NumElts, I, TII);
1661     }
1662     SrcReg = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1663     selectSelect(SrcReg, TmpType, I, false);
1664   }
1665   return selectUnOpWithSrc(ResVReg, ResType, I, SrcReg, Opcode);
1666 }
1667 
1668 bool SPIRVInstructionSelector::selectExt(Register ResVReg,
1669                                          const SPIRVType *ResType,
1670                                          MachineInstr &I, bool IsSigned) const {
1671   Register SrcReg = I.getOperand(1).getReg();
1672   if (GR.isScalarOrVectorOfType(SrcReg, SPIRV::OpTypeBool))
1673     return selectSelect(ResVReg, ResType, I, IsSigned);
1674 
1675   SPIRVType *SrcType = GR.getSPIRVTypeForVReg(SrcReg);
1676   if (SrcType == ResType)
1677     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1678                    TII.get(TargetOpcode::COPY))
1679         .addDef(ResVReg)
1680         .addUse(SrcReg)
1681         .constrainAllUses(TII, TRI, RBI);
1682 
1683   unsigned Opcode = IsSigned ? SPIRV::OpSConvert : SPIRV::OpUConvert;
1684   return selectUnOp(ResVReg, ResType, I, Opcode);
1685 }
1686 
1687 bool SPIRVInstructionSelector::selectIntToBool(Register IntReg,
1688                                                Register ResVReg,
1689                                                MachineInstr &I,
1690                                                const SPIRVType *IntTy,
1691                                                const SPIRVType *BoolTy) const {
1692   // To truncate to a bool, we use OpBitwiseAnd 1 and OpINotEqual to zero.
1693   Register BitIntReg = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1694   bool IsVectorTy = IntTy->getOpcode() == SPIRV::OpTypeVector;
1695   unsigned Opcode = IsVectorTy ? SPIRV::OpBitwiseAndV : SPIRV::OpBitwiseAndS;
1696   Register Zero = buildZerosVal(IntTy, I);
1697   Register One = buildOnesVal(false, IntTy, I);
1698   MachineBasicBlock &BB = *I.getParent();
1699   BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
1700       .addDef(BitIntReg)
1701       .addUse(GR.getSPIRVTypeID(IntTy))
1702       .addUse(IntReg)
1703       .addUse(One)
1704       .constrainAllUses(TII, TRI, RBI);
1705   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpINotEqual))
1706       .addDef(ResVReg)
1707       .addUse(GR.getSPIRVTypeID(BoolTy))
1708       .addUse(BitIntReg)
1709       .addUse(Zero)
1710       .constrainAllUses(TII, TRI, RBI);
1711 }
1712 
1713 bool SPIRVInstructionSelector::selectTrunc(Register ResVReg,
1714                                            const SPIRVType *ResType,
1715                                            MachineInstr &I) const {
1716   Register IntReg = I.getOperand(1).getReg();
1717   const SPIRVType *ArgType = GR.getSPIRVTypeForVReg(IntReg);
1718   if (GR.isScalarOrVectorOfType(ResVReg, SPIRV::OpTypeBool))
1719     return selectIntToBool(IntReg, ResVReg, I, ArgType, ResType);
1720   if (ArgType == ResType)
1721     return BuildMI(*I.getParent(), I, I.getDebugLoc(),
1722                    TII.get(TargetOpcode::COPY))
1723         .addDef(ResVReg)
1724         .addUse(IntReg)
1725         .constrainAllUses(TII, TRI, RBI);
1726   bool IsSigned = GR.isScalarOrVectorSigned(ResType);
1727   unsigned Opcode = IsSigned ? SPIRV::OpSConvert : SPIRV::OpUConvert;
1728   return selectUnOp(ResVReg, ResType, I, Opcode);
1729 }
1730 
1731 bool SPIRVInstructionSelector::selectConst(Register ResVReg,
1732                                            const SPIRVType *ResType,
1733                                            const APInt &Imm,
1734                                            MachineInstr &I) const {
1735   unsigned TyOpcode = ResType->getOpcode();
1736   assert(TyOpcode != SPIRV::OpTypePointer || Imm.isZero());
1737   MachineBasicBlock &BB = *I.getParent();
1738   if ((TyOpcode == SPIRV::OpTypePointer || TyOpcode == SPIRV::OpTypeEvent) &&
1739       Imm.isZero())
1740     return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
1741         .addDef(ResVReg)
1742         .addUse(GR.getSPIRVTypeID(ResType))
1743         .constrainAllUses(TII, TRI, RBI);
1744   if (TyOpcode == SPIRV::OpTypeInt) {
1745     assert(Imm.getBitWidth() <= 64 && "Unsupported integer width!");
1746     Register Reg = GR.getOrCreateConstInt(Imm.getZExtValue(), I, ResType, TII);
1747     if (Reg == ResVReg)
1748       return true;
1749     return BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY))
1750         .addDef(ResVReg)
1751         .addUse(Reg)
1752         .constrainAllUses(TII, TRI, RBI);
1753   }
1754   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantI))
1755                  .addDef(ResVReg)
1756                  .addUse(GR.getSPIRVTypeID(ResType));
1757   // <=32-bit integers should be caught by the sdag pattern.
1758   assert(Imm.getBitWidth() > 32);
1759   addNumImm(Imm, MIB);
1760   return MIB.constrainAllUses(TII, TRI, RBI);
1761 }
1762 
1763 bool SPIRVInstructionSelector::selectOpUndef(Register ResVReg,
1764                                              const SPIRVType *ResType,
1765                                              MachineInstr &I) const {
1766   return BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpUndef))
1767       .addDef(ResVReg)
1768       .addUse(GR.getSPIRVTypeID(ResType))
1769       .constrainAllUses(TII, TRI, RBI);
1770 }
1771 
1772 static bool isImm(const MachineOperand &MO, MachineRegisterInfo *MRI) {
1773   assert(MO.isReg());
1774   const SPIRVType *TypeInst = MRI->getVRegDef(MO.getReg());
1775   if (TypeInst->getOpcode() != SPIRV::ASSIGN_TYPE)
1776     return false;
1777   assert(TypeInst->getOperand(1).isReg());
1778   MachineInstr *ImmInst = MRI->getVRegDef(TypeInst->getOperand(1).getReg());
1779   return ImmInst->getOpcode() == TargetOpcode::G_CONSTANT;
1780 }
1781 
1782 static int64_t foldImm(const MachineOperand &MO, MachineRegisterInfo *MRI) {
1783   const SPIRVType *TypeInst = MRI->getVRegDef(MO.getReg());
1784   MachineInstr *ImmInst = MRI->getVRegDef(TypeInst->getOperand(1).getReg());
1785   assert(ImmInst->getOpcode() == TargetOpcode::G_CONSTANT);
1786   return ImmInst->getOperand(1).getCImm()->getZExtValue();
1787 }
1788 
1789 bool SPIRVInstructionSelector::selectInsertVal(Register ResVReg,
1790                                                const SPIRVType *ResType,
1791                                                MachineInstr &I) const {
1792   MachineBasicBlock &BB = *I.getParent();
1793   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeInsert))
1794                  .addDef(ResVReg)
1795                  .addUse(GR.getSPIRVTypeID(ResType))
1796                  // object to insert
1797                  .addUse(I.getOperand(3).getReg())
1798                  // composite to insert into
1799                  .addUse(I.getOperand(2).getReg());
1800   for (unsigned i = 4; i < I.getNumOperands(); i++)
1801     MIB.addImm(foldImm(I.getOperand(i), MRI));
1802   return MIB.constrainAllUses(TII, TRI, RBI);
1803 }
1804 
1805 bool SPIRVInstructionSelector::selectExtractVal(Register ResVReg,
1806                                                 const SPIRVType *ResType,
1807                                                 MachineInstr &I) const {
1808   MachineBasicBlock &BB = *I.getParent();
1809   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
1810                  .addDef(ResVReg)
1811                  .addUse(GR.getSPIRVTypeID(ResType))
1812                  .addUse(I.getOperand(2).getReg());
1813   for (unsigned i = 3; i < I.getNumOperands(); i++)
1814     MIB.addImm(foldImm(I.getOperand(i), MRI));
1815   return MIB.constrainAllUses(TII, TRI, RBI);
1816 }
1817 
1818 bool SPIRVInstructionSelector::selectInsertElt(Register ResVReg,
1819                                                const SPIRVType *ResType,
1820                                                MachineInstr &I) const {
1821   if (isImm(I.getOperand(4), MRI))
1822     return selectInsertVal(ResVReg, ResType, I);
1823   MachineBasicBlock &BB = *I.getParent();
1824   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorInsertDynamic))
1825       .addDef(ResVReg)
1826       .addUse(GR.getSPIRVTypeID(ResType))
1827       .addUse(I.getOperand(2).getReg())
1828       .addUse(I.getOperand(3).getReg())
1829       .addUse(I.getOperand(4).getReg())
1830       .constrainAllUses(TII, TRI, RBI);
1831 }
1832 
1833 bool SPIRVInstructionSelector::selectExtractElt(Register ResVReg,
1834                                                 const SPIRVType *ResType,
1835                                                 MachineInstr &I) const {
1836   if (isImm(I.getOperand(3), MRI))
1837     return selectExtractVal(ResVReg, ResType, I);
1838   MachineBasicBlock &BB = *I.getParent();
1839   return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpVectorExtractDynamic))
1840       .addDef(ResVReg)
1841       .addUse(GR.getSPIRVTypeID(ResType))
1842       .addUse(I.getOperand(2).getReg())
1843       .addUse(I.getOperand(3).getReg())
1844       .constrainAllUses(TII, TRI, RBI);
1845 }
1846 
1847 bool SPIRVInstructionSelector::selectGEP(Register ResVReg,
1848                                          const SPIRVType *ResType,
1849                                          MachineInstr &I) const {
1850   const bool IsGEPInBounds = I.getOperand(2).getImm();
1851 
1852   // OpAccessChain could be used for OpenCL, but the SPIRV-LLVM Translator only
1853   // relies on PtrAccessChain, so we'll try not to deviate. For Vulkan however,
1854   // we have to use Op[InBounds]AccessChain.
1855   const unsigned Opcode = STI.isVulkanEnv()
1856                               ? (IsGEPInBounds ? SPIRV::OpInBoundsAccessChain
1857                                                : SPIRV::OpAccessChain)
1858                               : (IsGEPInBounds ? SPIRV::OpInBoundsPtrAccessChain
1859                                                : SPIRV::OpPtrAccessChain);
1860 
1861   auto Res = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(Opcode))
1862                  .addDef(ResVReg)
1863                  .addUse(GR.getSPIRVTypeID(ResType))
1864                  // Object to get a pointer to.
1865                  .addUse(I.getOperand(3).getReg());
1866   // Adding indices.
1867   const unsigned StartingIndex =
1868       (Opcode == SPIRV::OpAccessChain || Opcode == SPIRV::OpInBoundsAccessChain)
1869           ? 5
1870           : 4;
1871   for (unsigned i = StartingIndex; i < I.getNumExplicitOperands(); ++i)
1872     Res.addUse(I.getOperand(i).getReg());
1873   return Res.constrainAllUses(TII, TRI, RBI);
1874 }
1875 
1876 // Maybe wrap a value into OpSpecConstantOp
1877 bool SPIRVInstructionSelector::wrapIntoSpecConstantOp(
1878     MachineInstr &I, SmallVector<Register> &CompositeArgs) const {
1879   bool Result = true;
1880   unsigned Lim = I.getNumExplicitOperands();
1881   for (unsigned i = I.getNumExplicitDefs() + 1; i < Lim; ++i) {
1882     Register OpReg = I.getOperand(i).getReg();
1883     SPIRVType *OpDefine = MRI->getVRegDef(OpReg);
1884     SPIRVType *OpType = GR.getSPIRVTypeForVReg(OpReg);
1885     if (!OpDefine || !OpType || isConstReg(MRI, OpDefine) ||
1886         OpDefine->getOpcode() == TargetOpcode::G_ADDRSPACE_CAST) {
1887       // The case of G_ADDRSPACE_CAST inside spv_const_composite() is processed
1888       // by selectAddrSpaceCast()
1889       CompositeArgs.push_back(OpReg);
1890       continue;
1891     }
1892     MachineFunction *MF = I.getMF();
1893     Register WrapReg = GR.find(OpDefine, MF);
1894     if (WrapReg.isValid()) {
1895       CompositeArgs.push_back(WrapReg);
1896       continue;
1897     }
1898     // Create a new register for the wrapper
1899     WrapReg = MRI->createVirtualRegister(&SPIRV::IDRegClass);
1900     GR.add(OpDefine, MF, WrapReg);
1901     CompositeArgs.push_back(WrapReg);
1902     // Decorate the wrapper register and generate a new instruction
1903     MRI->setType(WrapReg, LLT::pointer(0, 32));
1904     GR.assignSPIRVTypeToVReg(OpType, WrapReg, *MF);
1905     MachineBasicBlock &BB = *I.getParent();
1906     Result = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSpecConstantOp))
1907                  .addDef(WrapReg)
1908                  .addUse(GR.getSPIRVTypeID(OpType))
1909                  .addImm(static_cast<uint32_t>(SPIRV::Opcode::Bitcast))
1910                  .addUse(OpReg)
1911                  .constrainAllUses(TII, TRI, RBI);
1912     if (!Result)
1913       break;
1914   }
1915   return Result;
1916 }
1917 
1918 bool SPIRVInstructionSelector::selectIntrinsic(Register ResVReg,
1919                                                const SPIRVType *ResType,
1920                                                MachineInstr &I) const {
1921   MachineBasicBlock &BB = *I.getParent();
1922   Intrinsic::ID IID = cast<GIntrinsic>(I).getIntrinsicID();
1923   switch (IID) {
1924   case Intrinsic::spv_load:
1925     return selectLoad(ResVReg, ResType, I);
1926   case Intrinsic::spv_store:
1927     return selectStore(I);
1928   case Intrinsic::spv_extractv:
1929     return selectExtractVal(ResVReg, ResType, I);
1930   case Intrinsic::spv_insertv:
1931     return selectInsertVal(ResVReg, ResType, I);
1932   case Intrinsic::spv_extractelt:
1933     return selectExtractElt(ResVReg, ResType, I);
1934   case Intrinsic::spv_insertelt:
1935     return selectInsertElt(ResVReg, ResType, I);
1936   case Intrinsic::spv_gep:
1937     return selectGEP(ResVReg, ResType, I);
1938   case Intrinsic::spv_unref_global:
1939   case Intrinsic::spv_init_global: {
1940     MachineInstr *MI = MRI->getVRegDef(I.getOperand(1).getReg());
1941     MachineInstr *Init = I.getNumExplicitOperands() > 2
1942                              ? MRI->getVRegDef(I.getOperand(2).getReg())
1943                              : nullptr;
1944     assert(MI);
1945     return selectGlobalValue(MI->getOperand(0).getReg(), *MI, Init);
1946   }
1947   case Intrinsic::spv_undef: {
1948     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpUndef))
1949                    .addDef(ResVReg)
1950                    .addUse(GR.getSPIRVTypeID(ResType));
1951     return MIB.constrainAllUses(TII, TRI, RBI);
1952   }
1953   case Intrinsic::spv_const_composite: {
1954     // If no values are attached, the composite is null constant.
1955     bool IsNull = I.getNumExplicitDefs() + 1 == I.getNumExplicitOperands();
1956     // Select a proper instruction.
1957     unsigned Opcode = SPIRV::OpConstantNull;
1958     SmallVector<Register> CompositeArgs;
1959     if (!IsNull) {
1960       Opcode = SPIRV::OpConstantComposite;
1961       if (!wrapIntoSpecConstantOp(I, CompositeArgs))
1962         return false;
1963     }
1964     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
1965                    .addDef(ResVReg)
1966                    .addUse(GR.getSPIRVTypeID(ResType));
1967     // skip type MD node we already used when generated assign.type for this
1968     if (!IsNull) {
1969       for (Register OpReg : CompositeArgs)
1970         MIB.addUse(OpReg);
1971     }
1972     return MIB.constrainAllUses(TII, TRI, RBI);
1973   }
1974   case Intrinsic::spv_assign_name: {
1975     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpName));
1976     MIB.addUse(I.getOperand(I.getNumExplicitDefs() + 1).getReg());
1977     for (unsigned i = I.getNumExplicitDefs() + 2;
1978          i < I.getNumExplicitOperands(); ++i) {
1979       MIB.addImm(I.getOperand(i).getImm());
1980     }
1981     return MIB.constrainAllUses(TII, TRI, RBI);
1982   }
1983   case Intrinsic::spv_switch: {
1984     auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpSwitch));
1985     for (unsigned i = 1; i < I.getNumExplicitOperands(); ++i) {
1986       if (I.getOperand(i).isReg())
1987         MIB.addReg(I.getOperand(i).getReg());
1988       else if (I.getOperand(i).isCImm())
1989         addNumImm(I.getOperand(i).getCImm()->getValue(), MIB);
1990       else if (I.getOperand(i).isMBB())
1991         MIB.addMBB(I.getOperand(i).getMBB());
1992       else
1993         llvm_unreachable("Unexpected OpSwitch operand");
1994     }
1995     return MIB.constrainAllUses(TII, TRI, RBI);
1996   }
1997   case Intrinsic::spv_cmpxchg:
1998     return selectAtomicCmpXchg(ResVReg, ResType, I);
1999   case Intrinsic::spv_unreachable:
2000     BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpUnreachable));
2001     break;
2002   case Intrinsic::spv_alloca:
2003     return selectFrameIndex(ResVReg, ResType, I);
2004   case Intrinsic::spv_alloca_array:
2005     return selectAllocaArray(ResVReg, ResType, I);
2006   case Intrinsic::spv_assume:
2007     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_expect_assume))
2008       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpAssumeTrueKHR))
2009           .addUse(I.getOperand(1).getReg());
2010     break;
2011   case Intrinsic::spv_expect:
2012     if (STI.canUseExtension(SPIRV::Extension::SPV_KHR_expect_assume))
2013       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExpectKHR))
2014           .addDef(ResVReg)
2015           .addUse(GR.getSPIRVTypeID(ResType))
2016           .addUse(I.getOperand(2).getReg())
2017           .addUse(I.getOperand(3).getReg());
2018     break;
2019   case Intrinsic::spv_thread_id:
2020     return selectSpvThreadId(ResVReg, ResType, I);
2021   case Intrinsic::spv_all:
2022     return selectAll(ResVReg, ResType, I);
2023   case Intrinsic::spv_any:
2024     return selectAny(ResVReg, ResType, I);
2025   case Intrinsic::spv_lerp:
2026     return selectFmix(ResVReg, ResType, I);
2027   case Intrinsic::spv_rsqrt:
2028     return selectRsqrt(ResVReg, ResType, I);
2029   case Intrinsic::spv_lifetime_start:
2030   case Intrinsic::spv_lifetime_end: {
2031     unsigned Op = IID == Intrinsic::spv_lifetime_start ? SPIRV::OpLifetimeStart
2032                                                        : SPIRV::OpLifetimeStop;
2033     int64_t Size = I.getOperand(I.getNumExplicitDefs() + 1).getImm();
2034     Register PtrReg = I.getOperand(I.getNumExplicitDefs() + 2).getReg();
2035     unsigned PonteeOpType = GR.getPointeeTypeOp(PtrReg);
2036     bool IsNonvoidPtr = PonteeOpType != 0 && PonteeOpType != SPIRV::OpTypeVoid;
2037     if (Size == -1 || IsNonvoidPtr)
2038       Size = 0;
2039     BuildMI(BB, I, I.getDebugLoc(), TII.get(Op)).addUse(PtrReg).addImm(Size);
2040   } break;
2041   default: {
2042     std::string DiagMsg;
2043     raw_string_ostream OS(DiagMsg);
2044     I.print(OS);
2045     DiagMsg = "Intrinsic selection not implemented: " + DiagMsg;
2046     report_fatal_error(DiagMsg.c_str(), false);
2047   }
2048   }
2049   return true;
2050 }
2051 
2052 bool SPIRVInstructionSelector::selectAllocaArray(Register ResVReg,
2053                                                  const SPIRVType *ResType,
2054                                                  MachineInstr &I) const {
2055   // there was an allocation size parameter to the allocation instruction
2056   // that is not 1
2057   MachineBasicBlock &BB = *I.getParent();
2058   return BuildMI(BB, I, I.getDebugLoc(),
2059                  TII.get(SPIRV::OpVariableLengthArrayINTEL))
2060       .addDef(ResVReg)
2061       .addUse(GR.getSPIRVTypeID(ResType))
2062       .addUse(I.getOperand(2).getReg())
2063       .constrainAllUses(TII, TRI, RBI);
2064 }
2065 
2066 bool SPIRVInstructionSelector::selectFrameIndex(Register ResVReg,
2067                                                 const SPIRVType *ResType,
2068                                                 MachineInstr &I) const {
2069   // Change order of instructions if needed: all OpVariable instructions in a
2070   // function must be the first instructions in the first block
2071   MachineFunction *MF = I.getParent()->getParent();
2072   MachineBasicBlock *MBB = &MF->front();
2073   auto It = MBB->SkipPHIsAndLabels(MBB->begin()), E = MBB->end();
2074   bool IsHeader = false;
2075   unsigned Opcode;
2076   for (; It != E && It != I; ++It) {
2077     Opcode = It->getOpcode();
2078     if (Opcode == SPIRV::OpFunction || Opcode == SPIRV::OpFunctionParameter) {
2079       IsHeader = true;
2080     } else if (IsHeader &&
2081                !(Opcode == SPIRV::ASSIGN_TYPE || Opcode == SPIRV::OpLabel)) {
2082       ++It;
2083       break;
2084     }
2085   }
2086   return BuildMI(*MBB, It, It->getDebugLoc(), TII.get(SPIRV::OpVariable))
2087       .addDef(ResVReg)
2088       .addUse(GR.getSPIRVTypeID(ResType))
2089       .addImm(static_cast<uint32_t>(SPIRV::StorageClass::Function))
2090       .constrainAllUses(TII, TRI, RBI);
2091 }
2092 
2093 bool SPIRVInstructionSelector::selectBranch(MachineInstr &I) const {
2094   // InstructionSelector walks backwards through the instructions. We can use
2095   // both a G_BR and a G_BRCOND to create an OpBranchConditional. We hit G_BR
2096   // first, so can generate an OpBranchConditional here. If there is no
2097   // G_BRCOND, we just use OpBranch for a regular unconditional branch.
2098   const MachineInstr *PrevI = I.getPrevNode();
2099   MachineBasicBlock &MBB = *I.getParent();
2100   if (PrevI != nullptr && PrevI->getOpcode() == TargetOpcode::G_BRCOND) {
2101     return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranchConditional))
2102         .addUse(PrevI->getOperand(0).getReg())
2103         .addMBB(PrevI->getOperand(1).getMBB())
2104         .addMBB(I.getOperand(0).getMBB())
2105         .constrainAllUses(TII, TRI, RBI);
2106   }
2107   return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranch))
2108       .addMBB(I.getOperand(0).getMBB())
2109       .constrainAllUses(TII, TRI, RBI);
2110 }
2111 
2112 bool SPIRVInstructionSelector::selectBranchCond(MachineInstr &I) const {
2113   // InstructionSelector walks backwards through the instructions. For an
2114   // explicit conditional branch with no fallthrough, we use both a G_BR and a
2115   // G_BRCOND to create an OpBranchConditional. We should hit G_BR first, and
2116   // generate the OpBranchConditional in selectBranch above.
2117   //
2118   // If an OpBranchConditional has been generated, we simply return, as the work
2119   // is alread done. If there is no OpBranchConditional, LLVM must be relying on
2120   // implicit fallthrough to the next basic block, so we need to create an
2121   // OpBranchConditional with an explicit "false" argument pointing to the next
2122   // basic block that LLVM would fall through to.
2123   const MachineInstr *NextI = I.getNextNode();
2124   // Check if this has already been successfully selected.
2125   if (NextI != nullptr && NextI->getOpcode() == SPIRV::OpBranchConditional)
2126     return true;
2127   // Must be relying on implicit block fallthrough, so generate an
2128   // OpBranchConditional with the "next" basic block as the "false" target.
2129   MachineBasicBlock &MBB = *I.getParent();
2130   unsigned NextMBBNum = MBB.getNextNode()->getNumber();
2131   MachineBasicBlock *NextMBB = I.getMF()->getBlockNumbered(NextMBBNum);
2132   return BuildMI(MBB, I, I.getDebugLoc(), TII.get(SPIRV::OpBranchConditional))
2133       .addUse(I.getOperand(0).getReg())
2134       .addMBB(I.getOperand(1).getMBB())
2135       .addMBB(NextMBB)
2136       .constrainAllUses(TII, TRI, RBI);
2137 }
2138 
2139 bool SPIRVInstructionSelector::selectPhi(Register ResVReg,
2140                                          const SPIRVType *ResType,
2141                                          MachineInstr &I) const {
2142   auto MIB = BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpPhi))
2143                  .addDef(ResVReg)
2144                  .addUse(GR.getSPIRVTypeID(ResType));
2145   const unsigned NumOps = I.getNumOperands();
2146   for (unsigned i = 1; i < NumOps; i += 2) {
2147     MIB.addUse(I.getOperand(i + 0).getReg());
2148     MIB.addMBB(I.getOperand(i + 1).getMBB());
2149   }
2150   return MIB.constrainAllUses(TII, TRI, RBI);
2151 }
2152 
2153 bool SPIRVInstructionSelector::selectGlobalValue(
2154     Register ResVReg, MachineInstr &I, const MachineInstr *Init) const {
2155   // FIXME: don't use MachineIRBuilder here, replace it with BuildMI.
2156   MachineIRBuilder MIRBuilder(I);
2157   const GlobalValue *GV = I.getOperand(1).getGlobal();
2158   Type *GVType = GR.getDeducedGlobalValueType(GV);
2159   SPIRVType *PointerBaseType;
2160   if (GVType->isArrayTy()) {
2161     SPIRVType *ArrayElementType =
2162         GR.getOrCreateSPIRVType(GVType->getArrayElementType(), MIRBuilder,
2163                                 SPIRV::AccessQualifier::ReadWrite, false);
2164     PointerBaseType = GR.getOrCreateSPIRVArrayType(
2165         ArrayElementType, GVType->getArrayNumElements(), I, TII);
2166   } else {
2167     PointerBaseType = GR.getOrCreateSPIRVType(
2168         GVType, MIRBuilder, SPIRV::AccessQualifier::ReadWrite, false);
2169   }
2170   SPIRVType *ResType = GR.getOrCreateSPIRVPointerType(
2171       PointerBaseType, I, TII,
2172       addressSpaceToStorageClass(GV->getAddressSpace(), STI));
2173 
2174   std::string GlobalIdent;
2175   if (!GV->hasName()) {
2176     unsigned &ID = UnnamedGlobalIDs[GV];
2177     if (ID == 0)
2178       ID = UnnamedGlobalIDs.size();
2179     GlobalIdent = "__unnamed_" + Twine(ID).str();
2180   } else {
2181     GlobalIdent = GV->getGlobalIdentifier();
2182   }
2183 
2184   // Behaviour of functions as operands depends on availability of the
2185   // corresponding extension (SPV_INTEL_function_pointers):
2186   // - If there is an extension to operate with functions as operands:
2187   // We create a proper constant operand and evaluate a correct type for a
2188   // function pointer.
2189   // - Without the required extension:
2190   // We have functions as operands in tests with blocks of instruction e.g. in
2191   // transcoding/global_block.ll. These operands are not used and should be
2192   // substituted by zero constants. Their type is expected to be always
2193   // OpTypePointer Function %uchar.
2194   if (isa<Function>(GV)) {
2195     const Constant *ConstVal = GV;
2196     MachineBasicBlock &BB = *I.getParent();
2197     Register NewReg = GR.find(ConstVal, GR.CurMF);
2198     if (!NewReg.isValid()) {
2199       Register NewReg = ResVReg;
2200       GR.add(ConstVal, GR.CurMF, NewReg);
2201       const Function *GVFun =
2202           STI.canUseExtension(SPIRV::Extension::SPV_INTEL_function_pointers)
2203               ? dyn_cast<Function>(GV)
2204               : nullptr;
2205       if (GVFun) {
2206         // References to a function via function pointers generate virtual
2207         // registers without a definition. We will resolve it later, during
2208         // module analysis stage.
2209         MachineRegisterInfo *MRI = MIRBuilder.getMRI();
2210         Register FuncVReg = MRI->createGenericVirtualRegister(LLT::scalar(32));
2211         MRI->setRegClass(FuncVReg, &SPIRV::IDRegClass);
2212         MachineInstrBuilder MB =
2213             BuildMI(BB, I, I.getDebugLoc(),
2214                     TII.get(SPIRV::OpConstantFunctionPointerINTEL))
2215                 .addDef(NewReg)
2216                 .addUse(GR.getSPIRVTypeID(ResType))
2217                 .addUse(FuncVReg);
2218         // mapping the function pointer to the used Function
2219         GR.recordFunctionPointer(&MB.getInstr()->getOperand(2), GVFun);
2220         return MB.constrainAllUses(TII, TRI, RBI);
2221       }
2222       return BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpConstantNull))
2223           .addDef(NewReg)
2224           .addUse(GR.getSPIRVTypeID(ResType))
2225           .constrainAllUses(TII, TRI, RBI);
2226     }
2227     assert(NewReg != ResVReg);
2228     return BuildMI(BB, I, I.getDebugLoc(), TII.get(TargetOpcode::COPY))
2229         .addDef(ResVReg)
2230         .addUse(NewReg)
2231         .constrainAllUses(TII, TRI, RBI);
2232   }
2233   auto GlobalVar = cast<GlobalVariable>(GV);
2234   assert(GlobalVar->getName() != "llvm.global.annotations");
2235 
2236   bool HasInit = GlobalVar->hasInitializer() &&
2237                  !isa<UndefValue>(GlobalVar->getInitializer());
2238   // Skip empty declaration for GVs with initilaizers till we get the decl with
2239   // passed initializer.
2240   if (HasInit && !Init)
2241     return true;
2242 
2243   unsigned AddrSpace = GV->getAddressSpace();
2244   SPIRV::StorageClass::StorageClass Storage =
2245       addressSpaceToStorageClass(AddrSpace, STI);
2246   bool HasLnkTy = GV->getLinkage() != GlobalValue::InternalLinkage &&
2247                   Storage != SPIRV::StorageClass::Function;
2248   SPIRV::LinkageType::LinkageType LnkType =
2249       (GV->isDeclaration() || GV->hasAvailableExternallyLinkage())
2250           ? SPIRV::LinkageType::Import
2251           : (GV->getLinkage() == GlobalValue::LinkOnceODRLinkage &&
2252                      STI.canUseExtension(SPIRV::Extension::SPV_KHR_linkonce_odr)
2253                  ? SPIRV::LinkageType::LinkOnceODR
2254                  : SPIRV::LinkageType::Export);
2255 
2256   Register Reg = GR.buildGlobalVariable(ResVReg, ResType, GlobalIdent, GV,
2257                                         Storage, Init, GlobalVar->isConstant(),
2258                                         HasLnkTy, LnkType, MIRBuilder, true);
2259   return Reg.isValid();
2260 }
2261 
2262 bool SPIRVInstructionSelector::selectLog10(Register ResVReg,
2263                                            const SPIRVType *ResType,
2264                                            MachineInstr &I) const {
2265   if (STI.canUseExtInstSet(SPIRV::InstructionSet::OpenCL_std)) {
2266     return selectExtInst(ResVReg, ResType, I, CL::log10);
2267   }
2268 
2269   // There is no log10 instruction in the GLSL Extended Instruction set, so it
2270   // is implemented as:
2271   // log10(x) = log2(x) * (1 / log2(10))
2272   //          = log2(x) * 0.30103
2273 
2274   MachineIRBuilder MIRBuilder(I);
2275   MachineBasicBlock &BB = *I.getParent();
2276 
2277   // Build log2(x).
2278   Register VarReg = MRI->createVirtualRegister(&SPIRV::IDRegClass);
2279   bool Result =
2280       BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpExtInst))
2281           .addDef(VarReg)
2282           .addUse(GR.getSPIRVTypeID(ResType))
2283           .addImm(static_cast<uint32_t>(SPIRV::InstructionSet::GLSL_std_450))
2284           .addImm(GL::Log2)
2285           .add(I.getOperand(1))
2286           .constrainAllUses(TII, TRI, RBI);
2287 
2288   // Build 0.30103.
2289   assert(ResType->getOpcode() == SPIRV::OpTypeVector ||
2290          ResType->getOpcode() == SPIRV::OpTypeFloat);
2291   // TODO: Add matrix implementation once supported by the HLSL frontend.
2292   const SPIRVType *SpirvScalarType =
2293       ResType->getOpcode() == SPIRV::OpTypeVector
2294           ? GR.getSPIRVTypeForVReg(ResType->getOperand(1).getReg())
2295           : ResType;
2296   Register ScaleReg =
2297       GR.buildConstantFP(APFloat(0.30103f), MIRBuilder, SpirvScalarType);
2298 
2299   // Multiply log2(x) by 0.30103 to get log10(x) result.
2300   auto Opcode = ResType->getOpcode() == SPIRV::OpTypeVector
2301                     ? SPIRV::OpVectorTimesScalar
2302                     : SPIRV::OpFMulS;
2303   Result &= BuildMI(BB, I, I.getDebugLoc(), TII.get(Opcode))
2304                 .addDef(ResVReg)
2305                 .addUse(GR.getSPIRVTypeID(ResType))
2306                 .addUse(VarReg)
2307                 .addUse(ScaleReg)
2308                 .constrainAllUses(TII, TRI, RBI);
2309 
2310   return Result;
2311 }
2312 
2313 bool SPIRVInstructionSelector::selectSpvThreadId(Register ResVReg,
2314                                                  const SPIRVType *ResType,
2315                                                  MachineInstr &I) const {
2316   // DX intrinsic: @llvm.dx.thread.id(i32)
2317   // ID  Name      Description
2318   // 93  ThreadId  reads the thread ID
2319 
2320   MachineIRBuilder MIRBuilder(I);
2321   const SPIRVType *U32Type = GR.getOrCreateSPIRVIntegerType(32, MIRBuilder);
2322   const SPIRVType *Vec3Ty =
2323       GR.getOrCreateSPIRVVectorType(U32Type, 3, MIRBuilder);
2324   const SPIRVType *PtrType = GR.getOrCreateSPIRVPointerType(
2325       Vec3Ty, MIRBuilder, SPIRV::StorageClass::Input);
2326 
2327   // Create new register for GlobalInvocationID builtin variable.
2328   Register NewRegister =
2329       MIRBuilder.getMRI()->createVirtualRegister(&SPIRV::IDRegClass);
2330   MIRBuilder.getMRI()->setType(NewRegister, LLT::pointer(0, 32));
2331   GR.assignSPIRVTypeToVReg(PtrType, NewRegister, MIRBuilder.getMF());
2332 
2333   // Build GlobalInvocationID global variable with the necessary decorations.
2334   Register Variable = GR.buildGlobalVariable(
2335       NewRegister, PtrType,
2336       getLinkStringForBuiltIn(SPIRV::BuiltIn::GlobalInvocationId), nullptr,
2337       SPIRV::StorageClass::Input, nullptr, true, true,
2338       SPIRV::LinkageType::Import, MIRBuilder, false);
2339 
2340   // Create new register for loading value.
2341   MachineRegisterInfo *MRI = MIRBuilder.getMRI();
2342   Register LoadedRegister = MRI->createVirtualRegister(&SPIRV::IDRegClass);
2343   MIRBuilder.getMRI()->setType(LoadedRegister, LLT::pointer(0, 32));
2344   GR.assignSPIRVTypeToVReg(Vec3Ty, LoadedRegister, MIRBuilder.getMF());
2345 
2346   // Load v3uint value from the global variable.
2347   BuildMI(*I.getParent(), I, I.getDebugLoc(), TII.get(SPIRV::OpLoad))
2348       .addDef(LoadedRegister)
2349       .addUse(GR.getSPIRVTypeID(Vec3Ty))
2350       .addUse(Variable);
2351 
2352   // Get Thread ID index. Expecting operand is a constant immediate value,
2353   // wrapped in a type assignment.
2354   assert(I.getOperand(2).isReg());
2355   Register ThreadIdReg = I.getOperand(2).getReg();
2356   SPIRVType *ConstTy = this->MRI->getVRegDef(ThreadIdReg);
2357   assert(ConstTy && ConstTy->getOpcode() == SPIRV::ASSIGN_TYPE &&
2358          ConstTy->getOperand(1).isReg());
2359   Register ConstReg = ConstTy->getOperand(1).getReg();
2360   const MachineInstr *Const = this->MRI->getVRegDef(ConstReg);
2361   assert(Const && Const->getOpcode() == TargetOpcode::G_CONSTANT);
2362   const llvm::APInt &Val = Const->getOperand(1).getCImm()->getValue();
2363   const uint32_t ThreadId = Val.getZExtValue();
2364 
2365   // Extract the thread ID from the loaded vector value.
2366   MachineBasicBlock &BB = *I.getParent();
2367   auto MIB = BuildMI(BB, I, I.getDebugLoc(), TII.get(SPIRV::OpCompositeExtract))
2368                  .addDef(ResVReg)
2369                  .addUse(GR.getSPIRVTypeID(ResType))
2370                  .addUse(LoadedRegister)
2371                  .addImm(ThreadId);
2372   return MIB.constrainAllUses(TII, TRI, RBI);
2373 }
2374 
2375 namespace llvm {
2376 InstructionSelector *
2377 createSPIRVInstructionSelector(const SPIRVTargetMachine &TM,
2378                                const SPIRVSubtarget &Subtarget,
2379                                const RegisterBankInfo &RBI) {
2380   return new SPIRVInstructionSelector(TM, Subtarget, RBI);
2381 }
2382 } // namespace llvm
2383