1 //===-- AMDGPUISelDAGToDAG.cpp - A dag to dag inst selector for AMDGPU ----===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //==-----------------------------------------------------------------------===//
9 //
10 /// \file
11 /// Defines an instruction selector for the AMDGPU target.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "AMDGPU.h"
16 #include "AMDGPUArgumentUsageInfo.h"
17 #include "AMDGPUISelLowering.h" // For AMDGPUISD
18 #include "AMDGPUInstrInfo.h"
19 #include "AMDGPUPerfHintAnalysis.h"
20 #include "AMDGPURegisterInfo.h"
21 #include "AMDGPUSubtarget.h"
22 #include "AMDGPUTargetMachine.h"
23 #include "SIDefines.h"
24 #include "SIISelLowering.h"
25 #include "SIInstrInfo.h"
26 #include "SIMachineFunctionInfo.h"
27 #include "SIRegisterInfo.h"
28 #include "MCTargetDesc/AMDGPUMCTargetDesc.h"
29 #include "llvm/ADT/APInt.h"
30 #include "llvm/ADT/SmallVector.h"
31 #include "llvm/ADT/StringRef.h"
32 #include "llvm/Analysis/LegacyDivergenceAnalysis.h"
33 #include "llvm/Analysis/ValueTracking.h"
34 #include "llvm/CodeGen/FunctionLoweringInfo.h"
35 #include "llvm/CodeGen/ISDOpcodes.h"
36 #include "llvm/CodeGen/MachineFunction.h"
37 #include "llvm/CodeGen/MachineRegisterInfo.h"
38 #include "llvm/CodeGen/SelectionDAG.h"
39 #include "llvm/CodeGen/SelectionDAGISel.h"
40 #include "llvm/CodeGen/SelectionDAGNodes.h"
41 #include "llvm/CodeGen/ValueTypes.h"
42 #include "llvm/IR/BasicBlock.h"
43 #include "llvm/IR/Instruction.h"
44 #include "llvm/MC/MCInstrDesc.h"
45 #include "llvm/Support/Casting.h"
46 #include "llvm/Support/CodeGen.h"
47 #include "llvm/Support/ErrorHandling.h"
48 #include "llvm/Support/MachineValueType.h"
49 #include "llvm/Support/MathExtras.h"
50 #include <cassert>
51 #include <cstdint>
52 #include <new>
53 #include <vector>
54 
55 using namespace llvm;
56 
57 namespace llvm {
58 
59 class R600InstrInfo;
60 
61 } // end namespace llvm
62 
63 //===----------------------------------------------------------------------===//
64 // Instruction Selector Implementation
65 //===----------------------------------------------------------------------===//
66 
67 namespace {
68 
69 /// AMDGPU specific code to select AMDGPU machine instructions for
70 /// SelectionDAG operations.
71 class AMDGPUDAGToDAGISel : public SelectionDAGISel {
72   // Subtarget - Keep a pointer to the AMDGPU Subtarget around so that we can
73   // make the right decision when generating code for different targets.
74   const GCNSubtarget *Subtarget;
75   bool EnableLateStructurizeCFG;
76 
77 public:
78   explicit AMDGPUDAGToDAGISel(TargetMachine *TM = nullptr,
79                               CodeGenOpt::Level OptLevel = CodeGenOpt::Default)
80     : SelectionDAGISel(*TM, OptLevel) {
81     EnableLateStructurizeCFG = AMDGPUTargetMachine::EnableLateStructurizeCFG;
82   }
83   ~AMDGPUDAGToDAGISel() override = default;
84 
85   void getAnalysisUsage(AnalysisUsage &AU) const override {
86     AU.addRequired<AMDGPUArgumentUsageInfo>();
87     AU.addRequired<AMDGPUPerfHintAnalysis>();
88     AU.addRequired<LegacyDivergenceAnalysis>();
89     SelectionDAGISel::getAnalysisUsage(AU);
90   }
91 
92   bool runOnMachineFunction(MachineFunction &MF) override;
93   void Select(SDNode *N) override;
94   StringRef getPassName() const override;
95   void PostprocessISelDAG() override;
96 
97 protected:
98   void SelectBuildVector(SDNode *N, unsigned RegClassID);
99 
100 private:
101   std::pair<SDValue, SDValue> foldFrameIndex(SDValue N) const;
102   bool isNoNanSrc(SDValue N) const;
103   bool isInlineImmediate(const SDNode *N) const;
104   bool isVGPRImm(const SDNode *N) const;
105   bool isUniformLoad(const SDNode *N) const;
106   bool isUniformBr(const SDNode *N) const;
107 
108   MachineSDNode *buildSMovImm64(SDLoc &DL, uint64_t Val, EVT VT) const;
109 
110   SDNode *glueCopyToM0(SDNode *N) const;
111 
112   const TargetRegisterClass *getOperandRegClass(SDNode *N, unsigned OpNo) const;
113   virtual bool SelectADDRVTX_READ(SDValue Addr, SDValue &Base, SDValue &Offset);
114   virtual bool SelectADDRIndirect(SDValue Addr, SDValue &Base, SDValue &Offset);
115   bool isDSOffsetLegal(const SDValue &Base, unsigned Offset,
116                        unsigned OffsetBits) const;
117   bool SelectDS1Addr1Offset(SDValue Ptr, SDValue &Base, SDValue &Offset) const;
118   bool SelectDS64Bit4ByteAligned(SDValue Ptr, SDValue &Base, SDValue &Offset0,
119                                  SDValue &Offset1) const;
120   bool SelectMUBUF(SDValue Addr, SDValue &SRsrc, SDValue &VAddr,
121                    SDValue &SOffset, SDValue &Offset, SDValue &Offen,
122                    SDValue &Idxen, SDValue &Addr64, SDValue &GLC, SDValue &SLC,
123                    SDValue &TFE) const;
124   bool SelectMUBUFAddr64(SDValue Addr, SDValue &SRsrc, SDValue &VAddr,
125                          SDValue &SOffset, SDValue &Offset, SDValue &GLC,
126                          SDValue &SLC, SDValue &TFE) const;
127   bool SelectMUBUFAddr64(SDValue Addr, SDValue &SRsrc,
128                          SDValue &VAddr, SDValue &SOffset, SDValue &Offset,
129                          SDValue &SLC) const;
130   bool SelectMUBUFScratchOffen(SDNode *Parent,
131                                SDValue Addr, SDValue &RSrc, SDValue &VAddr,
132                                SDValue &SOffset, SDValue &ImmOffset) const;
133   bool SelectMUBUFScratchOffset(SDNode *Parent,
134                                 SDValue Addr, SDValue &SRsrc, SDValue &Soffset,
135                                 SDValue &Offset) const;
136 
137   bool SelectMUBUFOffset(SDValue Addr, SDValue &SRsrc, SDValue &SOffset,
138                          SDValue &Offset, SDValue &GLC, SDValue &SLC,
139                          SDValue &TFE) const;
140   bool SelectMUBUFOffset(SDValue Addr, SDValue &SRsrc, SDValue &Soffset,
141                          SDValue &Offset, SDValue &SLC) const;
142   bool SelectMUBUFOffset(SDValue Addr, SDValue &SRsrc, SDValue &Soffset,
143                          SDValue &Offset) const;
144 
145   bool SelectFlatAtomic(SDValue Addr, SDValue &VAddr,
146                         SDValue &Offset, SDValue &SLC) const;
147   bool SelectFlatAtomicSigned(SDValue Addr, SDValue &VAddr,
148                               SDValue &Offset, SDValue &SLC) const;
149 
150   template <bool IsSigned>
151   bool SelectFlatOffset(SDValue Addr, SDValue &VAddr,
152                         SDValue &Offset, SDValue &SLC) const;
153 
154   bool SelectSMRDOffset(SDValue ByteOffsetNode, SDValue &Offset,
155                         bool &Imm) const;
156   SDValue Expand32BitAddress(SDValue Addr) const;
157   bool SelectSMRD(SDValue Addr, SDValue &SBase, SDValue &Offset,
158                   bool &Imm) const;
159   bool SelectSMRDImm(SDValue Addr, SDValue &SBase, SDValue &Offset) const;
160   bool SelectSMRDImm32(SDValue Addr, SDValue &SBase, SDValue &Offset) const;
161   bool SelectSMRDSgpr(SDValue Addr, SDValue &SBase, SDValue &Offset) const;
162   bool SelectSMRDBufferImm(SDValue Addr, SDValue &Offset) const;
163   bool SelectSMRDBufferImm32(SDValue Addr, SDValue &Offset) const;
164   bool SelectMOVRELOffset(SDValue Index, SDValue &Base, SDValue &Offset) const;
165 
166   bool SelectVOP3Mods_NNaN(SDValue In, SDValue &Src, SDValue &SrcMods) const;
167   bool SelectVOP3ModsImpl(SDValue In, SDValue &Src, unsigned &SrcMods) const;
168   bool SelectVOP3Mods(SDValue In, SDValue &Src, SDValue &SrcMods) const;
169   bool SelectVOP3NoMods(SDValue In, SDValue &Src) const;
170   bool SelectVOP3Mods0(SDValue In, SDValue &Src, SDValue &SrcMods,
171                        SDValue &Clamp, SDValue &Omod) const;
172   bool SelectVOP3NoMods0(SDValue In, SDValue &Src, SDValue &SrcMods,
173                          SDValue &Clamp, SDValue &Omod) const;
174 
175   bool SelectVOP3Mods0Clamp0OMod(SDValue In, SDValue &Src, SDValue &SrcMods,
176                                  SDValue &Clamp,
177                                  SDValue &Omod) const;
178 
179   bool SelectVOP3OMods(SDValue In, SDValue &Src,
180                        SDValue &Clamp, SDValue &Omod) const;
181 
182   bool SelectVOP3PMods(SDValue In, SDValue &Src, SDValue &SrcMods) const;
183   bool SelectVOP3PMods0(SDValue In, SDValue &Src, SDValue &SrcMods,
184                         SDValue &Clamp) const;
185 
186   bool SelectVOP3OpSel(SDValue In, SDValue &Src, SDValue &SrcMods) const;
187   bool SelectVOP3OpSel0(SDValue In, SDValue &Src, SDValue &SrcMods,
188                         SDValue &Clamp) const;
189 
190   bool SelectVOP3OpSelMods(SDValue In, SDValue &Src, SDValue &SrcMods) const;
191   bool SelectVOP3OpSelMods0(SDValue In, SDValue &Src, SDValue &SrcMods,
192                             SDValue &Clamp) const;
193   bool SelectVOP3PMadMixModsImpl(SDValue In, SDValue &Src, unsigned &Mods) const;
194   bool SelectVOP3PMadMixMods(SDValue In, SDValue &Src, SDValue &SrcMods) const;
195 
196   bool SelectHi16Elt(SDValue In, SDValue &Src) const;
197 
198   void SelectADD_SUB_I64(SDNode *N);
199   void SelectUADDO_USUBO(SDNode *N);
200   void SelectDIV_SCALE(SDNode *N);
201   void SelectMAD_64_32(SDNode *N);
202   void SelectFMA_W_CHAIN(SDNode *N);
203   void SelectFMUL_W_CHAIN(SDNode *N);
204 
205   SDNode *getS_BFE(unsigned Opcode, const SDLoc &DL, SDValue Val,
206                    uint32_t Offset, uint32_t Width);
207   void SelectS_BFEFromShifts(SDNode *N);
208   void SelectS_BFE(SDNode *N);
209   bool isCBranchSCC(const SDNode *N) const;
210   void SelectBRCOND(SDNode *N);
211   void SelectFMAD_FMA(SDNode *N);
212   void SelectATOMIC_CMP_SWAP(SDNode *N);
213 
214 protected:
215   // Include the pieces autogenerated from the target description.
216 #include "AMDGPUGenDAGISel.inc"
217 };
218 
219 class R600DAGToDAGISel : public AMDGPUDAGToDAGISel {
220   const R600Subtarget *Subtarget;
221 
222   bool isConstantLoad(const MemSDNode *N, int cbID) const;
223   bool SelectGlobalValueConstantOffset(SDValue Addr, SDValue& IntPtr);
224   bool SelectGlobalValueVariableOffset(SDValue Addr, SDValue &BaseReg,
225                                        SDValue& Offset);
226 public:
227   explicit R600DAGToDAGISel(TargetMachine *TM, CodeGenOpt::Level OptLevel) :
228       AMDGPUDAGToDAGISel(TM, OptLevel) {}
229 
230   void Select(SDNode *N) override;
231 
232   bool SelectADDRIndirect(SDValue Addr, SDValue &Base,
233                           SDValue &Offset) override;
234   bool SelectADDRVTX_READ(SDValue Addr, SDValue &Base,
235                           SDValue &Offset) override;
236 
237   bool runOnMachineFunction(MachineFunction &MF) override;
238 protected:
239   // Include the pieces autogenerated from the target description.
240 #include "R600GenDAGISel.inc"
241 };
242 
243 }  // end anonymous namespace
244 
245 INITIALIZE_PASS_BEGIN(AMDGPUDAGToDAGISel, "amdgpu-isel",
246                       "AMDGPU DAG->DAG Pattern Instruction Selection", false, false)
247 INITIALIZE_PASS_DEPENDENCY(AMDGPUArgumentUsageInfo)
248 INITIALIZE_PASS_DEPENDENCY(AMDGPUPerfHintAnalysis)
249 INITIALIZE_PASS_DEPENDENCY(LegacyDivergenceAnalysis)
250 INITIALIZE_PASS_END(AMDGPUDAGToDAGISel, "amdgpu-isel",
251                     "AMDGPU DAG->DAG Pattern Instruction Selection", false, false)
252 
253 /// This pass converts a legalized DAG into a AMDGPU-specific
254 // DAG, ready for instruction scheduling.
255 FunctionPass *llvm::createAMDGPUISelDag(TargetMachine *TM,
256                                         CodeGenOpt::Level OptLevel) {
257   return new AMDGPUDAGToDAGISel(TM, OptLevel);
258 }
259 
260 /// This pass converts a legalized DAG into a R600-specific
261 // DAG, ready for instruction scheduling.
262 FunctionPass *llvm::createR600ISelDag(TargetMachine *TM,
263                                       CodeGenOpt::Level OptLevel) {
264   return new R600DAGToDAGISel(TM, OptLevel);
265 }
266 
267 bool AMDGPUDAGToDAGISel::runOnMachineFunction(MachineFunction &MF) {
268   Subtarget = &MF.getSubtarget<GCNSubtarget>();
269   return SelectionDAGISel::runOnMachineFunction(MF);
270 }
271 
272 bool AMDGPUDAGToDAGISel::isNoNanSrc(SDValue N) const {
273   if (TM.Options.NoNaNsFPMath)
274     return true;
275 
276   // TODO: Move into isKnownNeverNaN
277   if (N->getFlags().isDefined())
278     return N->getFlags().hasNoNaNs();
279 
280   return CurDAG->isKnownNeverNaN(N);
281 }
282 
283 bool AMDGPUDAGToDAGISel::isInlineImmediate(const SDNode *N) const {
284   const SIInstrInfo *TII = Subtarget->getInstrInfo();
285 
286   if (const ConstantSDNode *C = dyn_cast<ConstantSDNode>(N))
287     return TII->isInlineConstant(C->getAPIntValue());
288 
289   if (const ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(N))
290     return TII->isInlineConstant(C->getValueAPF().bitcastToAPInt());
291 
292   return false;
293 }
294 
295 /// Determine the register class for \p OpNo
296 /// \returns The register class of the virtual register that will be used for
297 /// the given operand number \OpNo or NULL if the register class cannot be
298 /// determined.
299 const TargetRegisterClass *AMDGPUDAGToDAGISel::getOperandRegClass(SDNode *N,
300                                                           unsigned OpNo) const {
301   if (!N->isMachineOpcode()) {
302     if (N->getOpcode() == ISD::CopyToReg) {
303       unsigned Reg = cast<RegisterSDNode>(N->getOperand(1))->getReg();
304       if (TargetRegisterInfo::isVirtualRegister(Reg)) {
305         MachineRegisterInfo &MRI = CurDAG->getMachineFunction().getRegInfo();
306         return MRI.getRegClass(Reg);
307       }
308 
309       const SIRegisterInfo *TRI
310         = static_cast<const GCNSubtarget *>(Subtarget)->getRegisterInfo();
311       return TRI->getPhysRegClass(Reg);
312     }
313 
314     return nullptr;
315   }
316 
317   switch (N->getMachineOpcode()) {
318   default: {
319     const MCInstrDesc &Desc =
320         Subtarget->getInstrInfo()->get(N->getMachineOpcode());
321     unsigned OpIdx = Desc.getNumDefs() + OpNo;
322     if (OpIdx >= Desc.getNumOperands())
323       return nullptr;
324     int RegClass = Desc.OpInfo[OpIdx].RegClass;
325     if (RegClass == -1)
326       return nullptr;
327 
328     return Subtarget->getRegisterInfo()->getRegClass(RegClass);
329   }
330   case AMDGPU::REG_SEQUENCE: {
331     unsigned RCID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
332     const TargetRegisterClass *SuperRC =
333         Subtarget->getRegisterInfo()->getRegClass(RCID);
334 
335     SDValue SubRegOp = N->getOperand(OpNo + 1);
336     unsigned SubRegIdx = cast<ConstantSDNode>(SubRegOp)->getZExtValue();
337     return Subtarget->getRegisterInfo()->getSubClassWithSubReg(SuperRC,
338                                                               SubRegIdx);
339   }
340   }
341 }
342 
343 SDNode *AMDGPUDAGToDAGISel::glueCopyToM0(SDNode *N) const {
344   if (cast<MemSDNode>(N)->getAddressSpace() != AMDGPUAS::LOCAL_ADDRESS ||
345       !Subtarget->ldsRequiresM0Init())
346     return N;
347 
348   const SITargetLowering& Lowering =
349       *static_cast<const SITargetLowering*>(getTargetLowering());
350 
351   // Write max value to m0 before each load operation
352 
353   SDValue M0 = Lowering.copyToM0(*CurDAG, CurDAG->getEntryNode(), SDLoc(N),
354                                  CurDAG->getTargetConstant(-1, SDLoc(N), MVT::i32));
355 
356   SDValue Glue = M0.getValue(1);
357 
358   SmallVector <SDValue, 8> Ops;
359   for (unsigned i = 0, e = N->getNumOperands(); i != e; ++i) {
360      Ops.push_back(N->getOperand(i));
361   }
362   Ops.push_back(Glue);
363   return CurDAG->MorphNodeTo(N, N->getOpcode(), N->getVTList(), Ops);
364 }
365 
366 MachineSDNode *AMDGPUDAGToDAGISel::buildSMovImm64(SDLoc &DL, uint64_t Imm,
367                                                   EVT VT) const {
368   SDNode *Lo = CurDAG->getMachineNode(
369       AMDGPU::S_MOV_B32, DL, MVT::i32,
370       CurDAG->getConstant(Imm & 0xFFFFFFFF, DL, MVT::i32));
371   SDNode *Hi =
372       CurDAG->getMachineNode(AMDGPU::S_MOV_B32, DL, MVT::i32,
373                              CurDAG->getConstant(Imm >> 32, DL, MVT::i32));
374   const SDValue Ops[] = {
375       CurDAG->getTargetConstant(AMDGPU::SReg_64RegClassID, DL, MVT::i32),
376       SDValue(Lo, 0), CurDAG->getTargetConstant(AMDGPU::sub0, DL, MVT::i32),
377       SDValue(Hi, 0), CurDAG->getTargetConstant(AMDGPU::sub1, DL, MVT::i32)};
378 
379   return CurDAG->getMachineNode(TargetOpcode::REG_SEQUENCE, DL, VT, Ops);
380 }
381 
382 static unsigned selectSGPRVectorRegClassID(unsigned NumVectorElts) {
383   switch (NumVectorElts) {
384   case 1:
385     return AMDGPU::SReg_32_XM0RegClassID;
386   case 2:
387     return AMDGPU::SReg_64RegClassID;
388   case 4:
389     return AMDGPU::SReg_128RegClassID;
390   case 8:
391     return AMDGPU::SReg_256RegClassID;
392   case 16:
393     return AMDGPU::SReg_512RegClassID;
394   }
395 
396   llvm_unreachable("invalid vector size");
397 }
398 
399 static bool getConstantValue(SDValue N, uint32_t &Out) {
400   if (const ConstantSDNode *C = dyn_cast<ConstantSDNode>(N)) {
401     Out = C->getAPIntValue().getZExtValue();
402     return true;
403   }
404 
405   if (const ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(N)) {
406     Out = C->getValueAPF().bitcastToAPInt().getZExtValue();
407     return true;
408   }
409 
410   return false;
411 }
412 
413 void AMDGPUDAGToDAGISel::SelectBuildVector(SDNode *N, unsigned RegClassID) {
414   EVT VT = N->getValueType(0);
415   unsigned NumVectorElts = VT.getVectorNumElements();
416   EVT EltVT = VT.getVectorElementType();
417   SDLoc DL(N);
418   SDValue RegClass = CurDAG->getTargetConstant(RegClassID, DL, MVT::i32);
419 
420   if (NumVectorElts == 1) {
421     CurDAG->SelectNodeTo(N, AMDGPU::COPY_TO_REGCLASS, EltVT, N->getOperand(0),
422                          RegClass);
423     return;
424   }
425 
426   assert(NumVectorElts <= 16 && "Vectors with more than 16 elements not "
427                                   "supported yet");
428   // 16 = Max Num Vector Elements
429   // 2 = 2 REG_SEQUENCE operands per element (value, subreg index)
430   // 1 = Vector Register Class
431   SmallVector<SDValue, 16 * 2 + 1> RegSeqArgs(NumVectorElts * 2 + 1);
432 
433   RegSeqArgs[0] = CurDAG->getTargetConstant(RegClassID, DL, MVT::i32);
434   bool IsRegSeq = true;
435   unsigned NOps = N->getNumOperands();
436   for (unsigned i = 0; i < NOps; i++) {
437     // XXX: Why is this here?
438     if (isa<RegisterSDNode>(N->getOperand(i))) {
439       IsRegSeq = false;
440       break;
441     }
442     unsigned Sub = AMDGPURegisterInfo::getSubRegFromChannel(i);
443     RegSeqArgs[1 + (2 * i)] = N->getOperand(i);
444     RegSeqArgs[1 + (2 * i) + 1] = CurDAG->getTargetConstant(Sub, DL, MVT::i32);
445   }
446   if (NOps != NumVectorElts) {
447     // Fill in the missing undef elements if this was a scalar_to_vector.
448     assert(N->getOpcode() == ISD::SCALAR_TO_VECTOR && NOps < NumVectorElts);
449     MachineSDNode *ImpDef = CurDAG->getMachineNode(TargetOpcode::IMPLICIT_DEF,
450                                                    DL, EltVT);
451     for (unsigned i = NOps; i < NumVectorElts; ++i) {
452       unsigned Sub = AMDGPURegisterInfo::getSubRegFromChannel(i);
453       RegSeqArgs[1 + (2 * i)] = SDValue(ImpDef, 0);
454       RegSeqArgs[1 + (2 * i) + 1] =
455           CurDAG->getTargetConstant(Sub, DL, MVT::i32);
456     }
457   }
458 
459   if (!IsRegSeq)
460     SelectCode(N);
461   CurDAG->SelectNodeTo(N, AMDGPU::REG_SEQUENCE, N->getVTList(), RegSeqArgs);
462 }
463 
464 void AMDGPUDAGToDAGISel::Select(SDNode *N) {
465   unsigned int Opc = N->getOpcode();
466   if (N->isMachineOpcode()) {
467     N->setNodeId(-1);
468     return;   // Already selected.
469   }
470 
471   if (isa<AtomicSDNode>(N) ||
472       (Opc == AMDGPUISD::ATOMIC_INC || Opc == AMDGPUISD::ATOMIC_DEC ||
473        Opc == AMDGPUISD::ATOMIC_LOAD_FADD ||
474        Opc == AMDGPUISD::ATOMIC_LOAD_FMIN ||
475        Opc == AMDGPUISD::ATOMIC_LOAD_FMAX))
476     N = glueCopyToM0(N);
477 
478   switch (Opc) {
479   default:
480     break;
481   // We are selecting i64 ADD here instead of custom lower it during
482   // DAG legalization, so we can fold some i64 ADDs used for address
483   // calculation into the LOAD and STORE instructions.
484   case ISD::ADDC:
485   case ISD::ADDE:
486   case ISD::SUBC:
487   case ISD::SUBE: {
488     if (N->getValueType(0) != MVT::i64)
489       break;
490 
491     SelectADD_SUB_I64(N);
492     return;
493   }
494   case ISD::UADDO:
495   case ISD::USUBO: {
496     SelectUADDO_USUBO(N);
497     return;
498   }
499   case AMDGPUISD::FMUL_W_CHAIN: {
500     SelectFMUL_W_CHAIN(N);
501     return;
502   }
503   case AMDGPUISD::FMA_W_CHAIN: {
504     SelectFMA_W_CHAIN(N);
505     return;
506   }
507 
508   case ISD::SCALAR_TO_VECTOR:
509   case ISD::BUILD_VECTOR: {
510     EVT VT = N->getValueType(0);
511     unsigned NumVectorElts = VT.getVectorNumElements();
512     if (VT.getScalarSizeInBits() == 16) {
513       if (Opc == ISD::BUILD_VECTOR && NumVectorElts == 2) {
514         uint32_t LHSVal, RHSVal;
515         if (getConstantValue(N->getOperand(0), LHSVal) &&
516             getConstantValue(N->getOperand(1), RHSVal)) {
517           uint32_t K = LHSVal | (RHSVal << 16);
518           CurDAG->SelectNodeTo(N, AMDGPU::S_MOV_B32, VT,
519                                CurDAG->getTargetConstant(K, SDLoc(N), MVT::i32));
520           return;
521         }
522       }
523 
524       break;
525     }
526 
527     assert(VT.getVectorElementType().bitsEq(MVT::i32));
528     unsigned RegClassID = selectSGPRVectorRegClassID(NumVectorElts);
529     SelectBuildVector(N, RegClassID);
530     return;
531   }
532   case ISD::BUILD_PAIR: {
533     SDValue RC, SubReg0, SubReg1;
534     SDLoc DL(N);
535     if (N->getValueType(0) == MVT::i128) {
536       RC = CurDAG->getTargetConstant(AMDGPU::SReg_128RegClassID, DL, MVT::i32);
537       SubReg0 = CurDAG->getTargetConstant(AMDGPU::sub0_sub1, DL, MVT::i32);
538       SubReg1 = CurDAG->getTargetConstant(AMDGPU::sub2_sub3, DL, MVT::i32);
539     } else if (N->getValueType(0) == MVT::i64) {
540       RC = CurDAG->getTargetConstant(AMDGPU::SReg_64RegClassID, DL, MVT::i32);
541       SubReg0 = CurDAG->getTargetConstant(AMDGPU::sub0, DL, MVT::i32);
542       SubReg1 = CurDAG->getTargetConstant(AMDGPU::sub1, DL, MVT::i32);
543     } else {
544       llvm_unreachable("Unhandled value type for BUILD_PAIR");
545     }
546     const SDValue Ops[] = { RC, N->getOperand(0), SubReg0,
547                             N->getOperand(1), SubReg1 };
548     ReplaceNode(N, CurDAG->getMachineNode(TargetOpcode::REG_SEQUENCE, DL,
549                                           N->getValueType(0), Ops));
550     return;
551   }
552 
553   case ISD::Constant:
554   case ISD::ConstantFP: {
555     if (N->getValueType(0).getSizeInBits() != 64 || isInlineImmediate(N))
556       break;
557 
558     uint64_t Imm;
559     if (ConstantFPSDNode *FP = dyn_cast<ConstantFPSDNode>(N))
560       Imm = FP->getValueAPF().bitcastToAPInt().getZExtValue();
561     else {
562       ConstantSDNode *C = cast<ConstantSDNode>(N);
563       Imm = C->getZExtValue();
564     }
565 
566     SDLoc DL(N);
567     ReplaceNode(N, buildSMovImm64(DL, Imm, N->getValueType(0)));
568     return;
569   }
570   case ISD::LOAD:
571   case ISD::STORE:
572   case ISD::ATOMIC_LOAD:
573   case ISD::ATOMIC_STORE: {
574     N = glueCopyToM0(N);
575     break;
576   }
577 
578   case AMDGPUISD::BFE_I32:
579   case AMDGPUISD::BFE_U32: {
580     // There is a scalar version available, but unlike the vector version which
581     // has a separate operand for the offset and width, the scalar version packs
582     // the width and offset into a single operand. Try to move to the scalar
583     // version if the offsets are constant, so that we can try to keep extended
584     // loads of kernel arguments in SGPRs.
585 
586     // TODO: Technically we could try to pattern match scalar bitshifts of
587     // dynamic values, but it's probably not useful.
588     ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1));
589     if (!Offset)
590       break;
591 
592     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(N->getOperand(2));
593     if (!Width)
594       break;
595 
596     bool Signed = Opc == AMDGPUISD::BFE_I32;
597 
598     uint32_t OffsetVal = Offset->getZExtValue();
599     uint32_t WidthVal = Width->getZExtValue();
600 
601     ReplaceNode(N, getS_BFE(Signed ? AMDGPU::S_BFE_I32 : AMDGPU::S_BFE_U32,
602                             SDLoc(N), N->getOperand(0), OffsetVal, WidthVal));
603     return;
604   }
605   case AMDGPUISD::DIV_SCALE: {
606     SelectDIV_SCALE(N);
607     return;
608   }
609   case AMDGPUISD::MAD_I64_I32:
610   case AMDGPUISD::MAD_U64_U32: {
611     SelectMAD_64_32(N);
612     return;
613   }
614   case ISD::CopyToReg: {
615     const SITargetLowering& Lowering =
616       *static_cast<const SITargetLowering*>(getTargetLowering());
617     N = Lowering.legalizeTargetIndependentNode(N, *CurDAG);
618     break;
619   }
620   case ISD::AND:
621   case ISD::SRL:
622   case ISD::SRA:
623   case ISD::SIGN_EXTEND_INREG:
624     if (N->getValueType(0) != MVT::i32)
625       break;
626 
627     SelectS_BFE(N);
628     return;
629   case ISD::BRCOND:
630     SelectBRCOND(N);
631     return;
632   case ISD::FMAD:
633   case ISD::FMA:
634     SelectFMAD_FMA(N);
635     return;
636   case AMDGPUISD::ATOMIC_CMP_SWAP:
637     SelectATOMIC_CMP_SWAP(N);
638     return;
639   case AMDGPUISD::CVT_PKRTZ_F16_F32:
640   case AMDGPUISD::CVT_PKNORM_I16_F32:
641   case AMDGPUISD::CVT_PKNORM_U16_F32:
642   case AMDGPUISD::CVT_PK_U16_U32:
643   case AMDGPUISD::CVT_PK_I16_I32: {
644     // Hack around using a legal type if f16 is illegal.
645     if (N->getValueType(0) == MVT::i32) {
646       MVT NewVT = Opc == AMDGPUISD::CVT_PKRTZ_F16_F32 ? MVT::v2f16 : MVT::v2i16;
647       N = CurDAG->MorphNodeTo(N, N->getOpcode(), CurDAG->getVTList(NewVT),
648                               { N->getOperand(0), N->getOperand(1) });
649       SelectCode(N);
650       return;
651     }
652   }
653   }
654 
655   SelectCode(N);
656 }
657 
658 bool AMDGPUDAGToDAGISel::isUniformBr(const SDNode *N) const {
659   const BasicBlock *BB = FuncInfo->MBB->getBasicBlock();
660   const Instruction *Term = BB->getTerminator();
661   return Term->getMetadata("amdgpu.uniform") ||
662          Term->getMetadata("structurizecfg.uniform");
663 }
664 
665 StringRef AMDGPUDAGToDAGISel::getPassName() const {
666   return "AMDGPU DAG->DAG Pattern Instruction Selection";
667 }
668 
669 //===----------------------------------------------------------------------===//
670 // Complex Patterns
671 //===----------------------------------------------------------------------===//
672 
673 bool AMDGPUDAGToDAGISel::SelectADDRVTX_READ(SDValue Addr, SDValue &Base,
674                                             SDValue &Offset) {
675   return false;
676 }
677 
678 bool AMDGPUDAGToDAGISel::SelectADDRIndirect(SDValue Addr, SDValue &Base,
679                                             SDValue &Offset) {
680   ConstantSDNode *C;
681   SDLoc DL(Addr);
682 
683   if ((C = dyn_cast<ConstantSDNode>(Addr))) {
684     Base = CurDAG->getRegister(R600::INDIRECT_BASE_ADDR, MVT::i32);
685     Offset = CurDAG->getTargetConstant(C->getZExtValue(), DL, MVT::i32);
686   } else if ((Addr.getOpcode() == AMDGPUISD::DWORDADDR) &&
687              (C = dyn_cast<ConstantSDNode>(Addr.getOperand(0)))) {
688     Base = CurDAG->getRegister(R600::INDIRECT_BASE_ADDR, MVT::i32);
689     Offset = CurDAG->getTargetConstant(C->getZExtValue(), DL, MVT::i32);
690   } else if ((Addr.getOpcode() == ISD::ADD || Addr.getOpcode() == ISD::OR) &&
691             (C = dyn_cast<ConstantSDNode>(Addr.getOperand(1)))) {
692     Base = Addr.getOperand(0);
693     Offset = CurDAG->getTargetConstant(C->getZExtValue(), DL, MVT::i32);
694   } else {
695     Base = Addr;
696     Offset = CurDAG->getTargetConstant(0, DL, MVT::i32);
697   }
698 
699   return true;
700 }
701 
702 // FIXME: Should only handle addcarry/subcarry
703 void AMDGPUDAGToDAGISel::SelectADD_SUB_I64(SDNode *N) {
704   SDLoc DL(N);
705   SDValue LHS = N->getOperand(0);
706   SDValue RHS = N->getOperand(1);
707 
708   unsigned Opcode = N->getOpcode();
709   bool ConsumeCarry = (Opcode == ISD::ADDE || Opcode == ISD::SUBE);
710   bool ProduceCarry =
711       ConsumeCarry || Opcode == ISD::ADDC || Opcode == ISD::SUBC;
712   bool IsAdd = Opcode == ISD::ADD || Opcode == ISD::ADDC || Opcode == ISD::ADDE;
713 
714   SDValue Sub0 = CurDAG->getTargetConstant(AMDGPU::sub0, DL, MVT::i32);
715   SDValue Sub1 = CurDAG->getTargetConstant(AMDGPU::sub1, DL, MVT::i32);
716 
717   SDNode *Lo0 = CurDAG->getMachineNode(TargetOpcode::EXTRACT_SUBREG,
718                                        DL, MVT::i32, LHS, Sub0);
719   SDNode *Hi0 = CurDAG->getMachineNode(TargetOpcode::EXTRACT_SUBREG,
720                                        DL, MVT::i32, LHS, Sub1);
721 
722   SDNode *Lo1 = CurDAG->getMachineNode(TargetOpcode::EXTRACT_SUBREG,
723                                        DL, MVT::i32, RHS, Sub0);
724   SDNode *Hi1 = CurDAG->getMachineNode(TargetOpcode::EXTRACT_SUBREG,
725                                        DL, MVT::i32, RHS, Sub1);
726 
727   SDVTList VTList = CurDAG->getVTList(MVT::i32, MVT::Glue);
728 
729   unsigned Opc = IsAdd ? AMDGPU::S_ADD_U32 : AMDGPU::S_SUB_U32;
730   unsigned CarryOpc = IsAdd ? AMDGPU::S_ADDC_U32 : AMDGPU::S_SUBB_U32;
731 
732   SDNode *AddLo;
733   if (!ConsumeCarry) {
734     SDValue Args[] = { SDValue(Lo0, 0), SDValue(Lo1, 0) };
735     AddLo = CurDAG->getMachineNode(Opc, DL, VTList, Args);
736   } else {
737     SDValue Args[] = { SDValue(Lo0, 0), SDValue(Lo1, 0), N->getOperand(2) };
738     AddLo = CurDAG->getMachineNode(CarryOpc, DL, VTList, Args);
739   }
740   SDValue AddHiArgs[] = {
741     SDValue(Hi0, 0),
742     SDValue(Hi1, 0),
743     SDValue(AddLo, 1)
744   };
745   SDNode *AddHi = CurDAG->getMachineNode(CarryOpc, DL, VTList, AddHiArgs);
746 
747   SDValue RegSequenceArgs[] = {
748     CurDAG->getTargetConstant(AMDGPU::SReg_64RegClassID, DL, MVT::i32),
749     SDValue(AddLo,0),
750     Sub0,
751     SDValue(AddHi,0),
752     Sub1,
753   };
754   SDNode *RegSequence = CurDAG->getMachineNode(AMDGPU::REG_SEQUENCE, DL,
755                                                MVT::i64, RegSequenceArgs);
756 
757   if (ProduceCarry) {
758     // Replace the carry-use
759     ReplaceUses(SDValue(N, 1), SDValue(AddHi, 1));
760   }
761 
762   // Replace the remaining uses.
763   ReplaceNode(N, RegSequence);
764 }
765 
766 void AMDGPUDAGToDAGISel::SelectUADDO_USUBO(SDNode *N) {
767   // The name of the opcodes are misleading. v_add_i32/v_sub_i32 have unsigned
768   // carry out despite the _i32 name. These were renamed in VI to _U32.
769   // FIXME: We should probably rename the opcodes here.
770   unsigned Opc = N->getOpcode() == ISD::UADDO ?
771     AMDGPU::V_ADD_I32_e64 : AMDGPU::V_SUB_I32_e64;
772 
773   CurDAG->SelectNodeTo(N, Opc, N->getVTList(),
774                        { N->getOperand(0), N->getOperand(1) });
775 }
776 
777 void AMDGPUDAGToDAGISel::SelectFMA_W_CHAIN(SDNode *N) {
778   SDLoc SL(N);
779   //  src0_modifiers, src0,  src1_modifiers, src1, src2_modifiers, src2, clamp, omod
780   SDValue Ops[10];
781 
782   SelectVOP3Mods0(N->getOperand(1), Ops[1], Ops[0], Ops[6], Ops[7]);
783   SelectVOP3Mods(N->getOperand(2), Ops[3], Ops[2]);
784   SelectVOP3Mods(N->getOperand(3), Ops[5], Ops[4]);
785   Ops[8] = N->getOperand(0);
786   Ops[9] = N->getOperand(4);
787 
788   CurDAG->SelectNodeTo(N, AMDGPU::V_FMA_F32, N->getVTList(), Ops);
789 }
790 
791 void AMDGPUDAGToDAGISel::SelectFMUL_W_CHAIN(SDNode *N) {
792   SDLoc SL(N);
793   //    src0_modifiers, src0,  src1_modifiers, src1, clamp, omod
794   SDValue Ops[8];
795 
796   SelectVOP3Mods0(N->getOperand(1), Ops[1], Ops[0], Ops[4], Ops[5]);
797   SelectVOP3Mods(N->getOperand(2), Ops[3], Ops[2]);
798   Ops[6] = N->getOperand(0);
799   Ops[7] = N->getOperand(3);
800 
801   CurDAG->SelectNodeTo(N, AMDGPU::V_MUL_F32_e64, N->getVTList(), Ops);
802 }
803 
804 // We need to handle this here because tablegen doesn't support matching
805 // instructions with multiple outputs.
806 void AMDGPUDAGToDAGISel::SelectDIV_SCALE(SDNode *N) {
807   SDLoc SL(N);
808   EVT VT = N->getValueType(0);
809 
810   assert(VT == MVT::f32 || VT == MVT::f64);
811 
812   unsigned Opc
813     = (VT == MVT::f64) ? AMDGPU::V_DIV_SCALE_F64 : AMDGPU::V_DIV_SCALE_F32;
814 
815   SDValue Ops[] = { N->getOperand(0), N->getOperand(1), N->getOperand(2) };
816   CurDAG->SelectNodeTo(N, Opc, N->getVTList(), Ops);
817 }
818 
819 // We need to handle this here because tablegen doesn't support matching
820 // instructions with multiple outputs.
821 void AMDGPUDAGToDAGISel::SelectMAD_64_32(SDNode *N) {
822   SDLoc SL(N);
823   bool Signed = N->getOpcode() == AMDGPUISD::MAD_I64_I32;
824   unsigned Opc = Signed ? AMDGPU::V_MAD_I64_I32 : AMDGPU::V_MAD_U64_U32;
825 
826   SDValue Clamp = CurDAG->getTargetConstant(0, SL, MVT::i1);
827   SDValue Ops[] = { N->getOperand(0), N->getOperand(1), N->getOperand(2),
828                     Clamp };
829   CurDAG->SelectNodeTo(N, Opc, N->getVTList(), Ops);
830 }
831 
832 bool AMDGPUDAGToDAGISel::isDSOffsetLegal(const SDValue &Base, unsigned Offset,
833                                          unsigned OffsetBits) const {
834   if ((OffsetBits == 16 && !isUInt<16>(Offset)) ||
835       (OffsetBits == 8 && !isUInt<8>(Offset)))
836     return false;
837 
838   if (Subtarget->getGeneration() >= AMDGPUSubtarget::SEA_ISLANDS ||
839       Subtarget->unsafeDSOffsetFoldingEnabled())
840     return true;
841 
842   // On Southern Islands instruction with a negative base value and an offset
843   // don't seem to work.
844   return CurDAG->SignBitIsZero(Base);
845 }
846 
847 bool AMDGPUDAGToDAGISel::SelectDS1Addr1Offset(SDValue Addr, SDValue &Base,
848                                               SDValue &Offset) const {
849   SDLoc DL(Addr);
850   if (CurDAG->isBaseWithConstantOffset(Addr)) {
851     SDValue N0 = Addr.getOperand(0);
852     SDValue N1 = Addr.getOperand(1);
853     ConstantSDNode *C1 = cast<ConstantSDNode>(N1);
854     if (isDSOffsetLegal(N0, C1->getSExtValue(), 16)) {
855       // (add n0, c0)
856       Base = N0;
857       Offset = CurDAG->getTargetConstant(C1->getZExtValue(), DL, MVT::i16);
858       return true;
859     }
860   } else if (Addr.getOpcode() == ISD::SUB) {
861     // sub C, x -> add (sub 0, x), C
862     if (const ConstantSDNode *C = dyn_cast<ConstantSDNode>(Addr.getOperand(0))) {
863       int64_t ByteOffset = C->getSExtValue();
864       if (isUInt<16>(ByteOffset)) {
865         SDValue Zero = CurDAG->getTargetConstant(0, DL, MVT::i32);
866 
867         // XXX - This is kind of hacky. Create a dummy sub node so we can check
868         // the known bits in isDSOffsetLegal. We need to emit the selected node
869         // here, so this is thrown away.
870         SDValue Sub = CurDAG->getNode(ISD::SUB, DL, MVT::i32,
871                                       Zero, Addr.getOperand(1));
872 
873         if (isDSOffsetLegal(Sub, ByteOffset, 16)) {
874           // FIXME: Select to VOP3 version for with-carry.
875           unsigned SubOp = Subtarget->hasAddNoCarry() ?
876             AMDGPU::V_SUB_U32_e64 : AMDGPU::V_SUB_I32_e32;
877 
878           MachineSDNode *MachineSub
879             = CurDAG->getMachineNode(SubOp, DL, MVT::i32,
880                                      Zero, Addr.getOperand(1));
881 
882           Base = SDValue(MachineSub, 0);
883           Offset = CurDAG->getTargetConstant(ByteOffset, DL, MVT::i16);
884           return true;
885         }
886       }
887     }
888   } else if (const ConstantSDNode *CAddr = dyn_cast<ConstantSDNode>(Addr)) {
889     // If we have a constant address, prefer to put the constant into the
890     // offset. This can save moves to load the constant address since multiple
891     // operations can share the zero base address register, and enables merging
892     // into read2 / write2 instructions.
893 
894     SDLoc DL(Addr);
895 
896     if (isUInt<16>(CAddr->getZExtValue())) {
897       SDValue Zero = CurDAG->getTargetConstant(0, DL, MVT::i32);
898       MachineSDNode *MovZero = CurDAG->getMachineNode(AMDGPU::V_MOV_B32_e32,
899                                  DL, MVT::i32, Zero);
900       Base = SDValue(MovZero, 0);
901       Offset = CurDAG->getTargetConstant(CAddr->getZExtValue(), DL, MVT::i16);
902       return true;
903     }
904   }
905 
906   // default case
907   Base = Addr;
908   Offset = CurDAG->getTargetConstant(0, SDLoc(Addr), MVT::i16);
909   return true;
910 }
911 
912 // TODO: If offset is too big, put low 16-bit into offset.
913 bool AMDGPUDAGToDAGISel::SelectDS64Bit4ByteAligned(SDValue Addr, SDValue &Base,
914                                                    SDValue &Offset0,
915                                                    SDValue &Offset1) const {
916   SDLoc DL(Addr);
917 
918   if (CurDAG->isBaseWithConstantOffset(Addr)) {
919     SDValue N0 = Addr.getOperand(0);
920     SDValue N1 = Addr.getOperand(1);
921     ConstantSDNode *C1 = cast<ConstantSDNode>(N1);
922     unsigned DWordOffset0 = C1->getZExtValue() / 4;
923     unsigned DWordOffset1 = DWordOffset0 + 1;
924     // (add n0, c0)
925     if (isDSOffsetLegal(N0, DWordOffset1, 8)) {
926       Base = N0;
927       Offset0 = CurDAG->getTargetConstant(DWordOffset0, DL, MVT::i8);
928       Offset1 = CurDAG->getTargetConstant(DWordOffset1, DL, MVT::i8);
929       return true;
930     }
931   } else if (Addr.getOpcode() == ISD::SUB) {
932     // sub C, x -> add (sub 0, x), C
933     if (const ConstantSDNode *C = dyn_cast<ConstantSDNode>(Addr.getOperand(0))) {
934       unsigned DWordOffset0 = C->getZExtValue() / 4;
935       unsigned DWordOffset1 = DWordOffset0 + 1;
936 
937       if (isUInt<8>(DWordOffset0)) {
938         SDLoc DL(Addr);
939         SDValue Zero = CurDAG->getTargetConstant(0, DL, MVT::i32);
940 
941         // XXX - This is kind of hacky. Create a dummy sub node so we can check
942         // the known bits in isDSOffsetLegal. We need to emit the selected node
943         // here, so this is thrown away.
944         SDValue Sub = CurDAG->getNode(ISD::SUB, DL, MVT::i32,
945                                       Zero, Addr.getOperand(1));
946 
947         if (isDSOffsetLegal(Sub, DWordOffset1, 8)) {
948           unsigned SubOp = Subtarget->hasAddNoCarry() ?
949             AMDGPU::V_SUB_U32_e64 : AMDGPU::V_SUB_I32_e32;
950 
951           MachineSDNode *MachineSub
952             = CurDAG->getMachineNode(SubOp, DL, MVT::i32,
953                                      Zero, Addr.getOperand(1));
954 
955           Base = SDValue(MachineSub, 0);
956           Offset0 = CurDAG->getTargetConstant(DWordOffset0, DL, MVT::i8);
957           Offset1 = CurDAG->getTargetConstant(DWordOffset1, DL, MVT::i8);
958           return true;
959         }
960       }
961     }
962   } else if (const ConstantSDNode *CAddr = dyn_cast<ConstantSDNode>(Addr)) {
963     unsigned DWordOffset0 = CAddr->getZExtValue() / 4;
964     unsigned DWordOffset1 = DWordOffset0 + 1;
965     assert(4 * DWordOffset0 == CAddr->getZExtValue());
966 
967     if (isUInt<8>(DWordOffset0) && isUInt<8>(DWordOffset1)) {
968       SDValue Zero = CurDAG->getTargetConstant(0, DL, MVT::i32);
969       MachineSDNode *MovZero
970         = CurDAG->getMachineNode(AMDGPU::V_MOV_B32_e32,
971                                  DL, MVT::i32, Zero);
972       Base = SDValue(MovZero, 0);
973       Offset0 = CurDAG->getTargetConstant(DWordOffset0, DL, MVT::i8);
974       Offset1 = CurDAG->getTargetConstant(DWordOffset1, DL, MVT::i8);
975       return true;
976     }
977   }
978 
979   // default case
980 
981   Base = Addr;
982   Offset0 = CurDAG->getTargetConstant(0, DL, MVT::i8);
983   Offset1 = CurDAG->getTargetConstant(1, DL, MVT::i8);
984   return true;
985 }
986 
987 bool AMDGPUDAGToDAGISel::SelectMUBUF(SDValue Addr, SDValue &Ptr,
988                                      SDValue &VAddr, SDValue &SOffset,
989                                      SDValue &Offset, SDValue &Offen,
990                                      SDValue &Idxen, SDValue &Addr64,
991                                      SDValue &GLC, SDValue &SLC,
992                                      SDValue &TFE) const {
993   // Subtarget prefers to use flat instruction
994   if (Subtarget->useFlatForGlobal())
995     return false;
996 
997   SDLoc DL(Addr);
998 
999   if (!GLC.getNode())
1000     GLC = CurDAG->getTargetConstant(0, DL, MVT::i1);
1001   if (!SLC.getNode())
1002     SLC = CurDAG->getTargetConstant(0, DL, MVT::i1);
1003   TFE = CurDAG->getTargetConstant(0, DL, MVT::i1);
1004 
1005   Idxen = CurDAG->getTargetConstant(0, DL, MVT::i1);
1006   Offen = CurDAG->getTargetConstant(0, DL, MVT::i1);
1007   Addr64 = CurDAG->getTargetConstant(0, DL, MVT::i1);
1008   SOffset = CurDAG->getTargetConstant(0, DL, MVT::i32);
1009 
1010   ConstantSDNode *C1 = nullptr;
1011   SDValue N0 = Addr;
1012   if (CurDAG->isBaseWithConstantOffset(Addr)) {
1013     C1 = cast<ConstantSDNode>(Addr.getOperand(1));
1014     if (isUInt<32>(C1->getZExtValue()))
1015       N0 = Addr.getOperand(0);
1016     else
1017       C1 = nullptr;
1018   }
1019 
1020   if (N0.getOpcode() == ISD::ADD) {
1021     // (add N2, N3) -> addr64, or
1022     // (add (add N2, N3), C1) -> addr64
1023     SDValue N2 = N0.getOperand(0);
1024     SDValue N3 = N0.getOperand(1);
1025     Addr64 = CurDAG->getTargetConstant(1, DL, MVT::i1);
1026 
1027     if (N2->isDivergent()) {
1028       if (N3->isDivergent()) {
1029         // Both N2 and N3 are divergent. Use N0 (the result of the add) as the
1030         // addr64, and construct the resource from a 0 address.
1031         Ptr = SDValue(buildSMovImm64(DL, 0, MVT::v2i32), 0);
1032         VAddr = N0;
1033       } else {
1034         // N2 is divergent, N3 is not.
1035         Ptr = N3;
1036         VAddr = N2;
1037       }
1038     } else {
1039       // N2 is not divergent.
1040       Ptr = N2;
1041       VAddr = N3;
1042     }
1043     Offset = CurDAG->getTargetConstant(0, DL, MVT::i16);
1044   } else if (N0->isDivergent()) {
1045     // N0 is divergent. Use it as the addr64, and construct the resource from a
1046     // 0 address.
1047     Ptr = SDValue(buildSMovImm64(DL, 0, MVT::v2i32), 0);
1048     VAddr = N0;
1049     Addr64 = CurDAG->getTargetConstant(1, DL, MVT::i1);
1050   } else {
1051     // N0 -> offset, or
1052     // (N0 + C1) -> offset
1053     VAddr = CurDAG->getTargetConstant(0, DL, MVT::i32);
1054     Ptr = N0;
1055   }
1056 
1057   if (!C1) {
1058     // No offset.
1059     Offset = CurDAG->getTargetConstant(0, DL, MVT::i16);
1060     return true;
1061   }
1062 
1063   if (SIInstrInfo::isLegalMUBUFImmOffset(C1->getZExtValue())) {
1064     // Legal offset for instruction.
1065     Offset = CurDAG->getTargetConstant(C1->getZExtValue(), DL, MVT::i16);
1066     return true;
1067   }
1068 
1069   // Illegal offset, store it in soffset.
1070   Offset = CurDAG->getTargetConstant(0, DL, MVT::i16);
1071   SOffset =
1072       SDValue(CurDAG->getMachineNode(
1073                   AMDGPU::S_MOV_B32, DL, MVT::i32,
1074                   CurDAG->getTargetConstant(C1->getZExtValue(), DL, MVT::i32)),
1075               0);
1076   return true;
1077 }
1078 
1079 bool AMDGPUDAGToDAGISel::SelectMUBUFAddr64(SDValue Addr, SDValue &SRsrc,
1080                                            SDValue &VAddr, SDValue &SOffset,
1081                                            SDValue &Offset, SDValue &GLC,
1082                                            SDValue &SLC, SDValue &TFE) const {
1083   SDValue Ptr, Offen, Idxen, Addr64;
1084 
1085   // addr64 bit was removed for volcanic islands.
1086   if (Subtarget->getGeneration() >= AMDGPUSubtarget::VOLCANIC_ISLANDS)
1087     return false;
1088 
1089   if (!SelectMUBUF(Addr, Ptr, VAddr, SOffset, Offset, Offen, Idxen, Addr64,
1090               GLC, SLC, TFE))
1091     return false;
1092 
1093   ConstantSDNode *C = cast<ConstantSDNode>(Addr64);
1094   if (C->getSExtValue()) {
1095     SDLoc DL(Addr);
1096 
1097     const SITargetLowering& Lowering =
1098       *static_cast<const SITargetLowering*>(getTargetLowering());
1099 
1100     SRsrc = SDValue(Lowering.wrapAddr64Rsrc(*CurDAG, DL, Ptr), 0);
1101     return true;
1102   }
1103 
1104   return false;
1105 }
1106 
1107 bool AMDGPUDAGToDAGISel::SelectMUBUFAddr64(SDValue Addr, SDValue &SRsrc,
1108                                            SDValue &VAddr, SDValue &SOffset,
1109                                            SDValue &Offset,
1110                                            SDValue &SLC) const {
1111   SLC = CurDAG->getTargetConstant(0, SDLoc(Addr), MVT::i1);
1112   SDValue GLC, TFE;
1113 
1114   return SelectMUBUFAddr64(Addr, SRsrc, VAddr, SOffset, Offset, GLC, SLC, TFE);
1115 }
1116 
1117 static bool isStackPtrRelative(const MachinePointerInfo &PtrInfo) {
1118   auto PSV = PtrInfo.V.dyn_cast<const PseudoSourceValue *>();
1119   return PSV && PSV->isStack();
1120 }
1121 
1122 std::pair<SDValue, SDValue> AMDGPUDAGToDAGISel::foldFrameIndex(SDValue N) const {
1123   const MachineFunction &MF = CurDAG->getMachineFunction();
1124   const SIMachineFunctionInfo *Info = MF.getInfo<SIMachineFunctionInfo>();
1125 
1126   if (auto FI = dyn_cast<FrameIndexSDNode>(N)) {
1127     SDValue TFI = CurDAG->getTargetFrameIndex(FI->getIndex(),
1128                                               FI->getValueType(0));
1129 
1130     // If we can resolve this to a frame index access, this is relative to the
1131     // frame pointer SGPR.
1132     return std::make_pair(TFI, CurDAG->getRegister(Info->getFrameOffsetReg(),
1133                                                    MVT::i32));
1134   }
1135 
1136   // If we don't know this private access is a local stack object, it needs to
1137   // be relative to the entry point's scratch wave offset register.
1138   return std::make_pair(N, CurDAG->getRegister(Info->getScratchWaveOffsetReg(),
1139                                                MVT::i32));
1140 }
1141 
1142 bool AMDGPUDAGToDAGISel::SelectMUBUFScratchOffen(SDNode *Parent,
1143                                                  SDValue Addr, SDValue &Rsrc,
1144                                                  SDValue &VAddr, SDValue &SOffset,
1145                                                  SDValue &ImmOffset) const {
1146 
1147   SDLoc DL(Addr);
1148   MachineFunction &MF = CurDAG->getMachineFunction();
1149   const SIMachineFunctionInfo *Info = MF.getInfo<SIMachineFunctionInfo>();
1150 
1151   Rsrc = CurDAG->getRegister(Info->getScratchRSrcReg(), MVT::v4i32);
1152 
1153   if (ConstantSDNode *CAddr = dyn_cast<ConstantSDNode>(Addr)) {
1154     unsigned Imm = CAddr->getZExtValue();
1155 
1156     SDValue HighBits = CurDAG->getTargetConstant(Imm & ~4095, DL, MVT::i32);
1157     MachineSDNode *MovHighBits = CurDAG->getMachineNode(AMDGPU::V_MOV_B32_e32,
1158                                                         DL, MVT::i32, HighBits);
1159     VAddr = SDValue(MovHighBits, 0);
1160 
1161     // In a call sequence, stores to the argument stack area are relative to the
1162     // stack pointer.
1163     const MachinePointerInfo &PtrInfo = cast<MemSDNode>(Parent)->getPointerInfo();
1164     unsigned SOffsetReg = isStackPtrRelative(PtrInfo) ?
1165       Info->getStackPtrOffsetReg() : Info->getScratchWaveOffsetReg();
1166 
1167     SOffset = CurDAG->getRegister(SOffsetReg, MVT::i32);
1168     ImmOffset = CurDAG->getTargetConstant(Imm & 4095, DL, MVT::i16);
1169     return true;
1170   }
1171 
1172   if (CurDAG->isBaseWithConstantOffset(Addr)) {
1173     // (add n0, c1)
1174 
1175     SDValue N0 = Addr.getOperand(0);
1176     SDValue N1 = Addr.getOperand(1);
1177 
1178     // Offsets in vaddr must be positive if range checking is enabled.
1179     //
1180     // The total computation of vaddr + soffset + offset must not overflow.  If
1181     // vaddr is negative, even if offset is 0 the sgpr offset add will end up
1182     // overflowing.
1183     //
1184     // Prior to gfx9, MUBUF instructions with the vaddr offset enabled would
1185     // always perform a range check. If a negative vaddr base index was used,
1186     // this would fail the range check. The overall address computation would
1187     // compute a valid address, but this doesn't happen due to the range
1188     // check. For out-of-bounds MUBUF loads, a 0 is returned.
1189     //
1190     // Therefore it should be safe to fold any VGPR offset on gfx9 into the
1191     // MUBUF vaddr, but not on older subtargets which can only do this if the
1192     // sign bit is known 0.
1193     ConstantSDNode *C1 = cast<ConstantSDNode>(N1);
1194     if (SIInstrInfo::isLegalMUBUFImmOffset(C1->getZExtValue()) &&
1195         (!Subtarget->privateMemoryResourceIsRangeChecked() ||
1196          CurDAG->SignBitIsZero(N0))) {
1197       std::tie(VAddr, SOffset) = foldFrameIndex(N0);
1198       ImmOffset = CurDAG->getTargetConstant(C1->getZExtValue(), DL, MVT::i16);
1199       return true;
1200     }
1201   }
1202 
1203   // (node)
1204   std::tie(VAddr, SOffset) = foldFrameIndex(Addr);
1205   ImmOffset = CurDAG->getTargetConstant(0, DL, MVT::i16);
1206   return true;
1207 }
1208 
1209 bool AMDGPUDAGToDAGISel::SelectMUBUFScratchOffset(SDNode *Parent,
1210                                                   SDValue Addr,
1211                                                   SDValue &SRsrc,
1212                                                   SDValue &SOffset,
1213                                                   SDValue &Offset) const {
1214   ConstantSDNode *CAddr = dyn_cast<ConstantSDNode>(Addr);
1215   if (!CAddr || !SIInstrInfo::isLegalMUBUFImmOffset(CAddr->getZExtValue()))
1216     return false;
1217 
1218   SDLoc DL(Addr);
1219   MachineFunction &MF = CurDAG->getMachineFunction();
1220   const SIMachineFunctionInfo *Info = MF.getInfo<SIMachineFunctionInfo>();
1221 
1222   SRsrc = CurDAG->getRegister(Info->getScratchRSrcReg(), MVT::v4i32);
1223 
1224   const MachinePointerInfo &PtrInfo = cast<MemSDNode>(Parent)->getPointerInfo();
1225   unsigned SOffsetReg = isStackPtrRelative(PtrInfo) ?
1226     Info->getStackPtrOffsetReg() : Info->getScratchWaveOffsetReg();
1227 
1228   // FIXME: Get from MachinePointerInfo? We should only be using the frame
1229   // offset if we know this is in a call sequence.
1230   SOffset = CurDAG->getRegister(SOffsetReg, MVT::i32);
1231 
1232   Offset = CurDAG->getTargetConstant(CAddr->getZExtValue(), DL, MVT::i16);
1233   return true;
1234 }
1235 
1236 bool AMDGPUDAGToDAGISel::SelectMUBUFOffset(SDValue Addr, SDValue &SRsrc,
1237                                            SDValue &SOffset, SDValue &Offset,
1238                                            SDValue &GLC, SDValue &SLC,
1239                                            SDValue &TFE) const {
1240   SDValue Ptr, VAddr, Offen, Idxen, Addr64;
1241   const SIInstrInfo *TII =
1242     static_cast<const SIInstrInfo *>(Subtarget->getInstrInfo());
1243 
1244   if (!SelectMUBUF(Addr, Ptr, VAddr, SOffset, Offset, Offen, Idxen, Addr64,
1245               GLC, SLC, TFE))
1246     return false;
1247 
1248   if (!cast<ConstantSDNode>(Offen)->getSExtValue() &&
1249       !cast<ConstantSDNode>(Idxen)->getSExtValue() &&
1250       !cast<ConstantSDNode>(Addr64)->getSExtValue()) {
1251     uint64_t Rsrc = TII->getDefaultRsrcDataFormat() |
1252                     APInt::getAllOnesValue(32).getZExtValue(); // Size
1253     SDLoc DL(Addr);
1254 
1255     const SITargetLowering& Lowering =
1256       *static_cast<const SITargetLowering*>(getTargetLowering());
1257 
1258     SRsrc = SDValue(Lowering.buildRSRC(*CurDAG, DL, Ptr, 0, Rsrc), 0);
1259     return true;
1260   }
1261   return false;
1262 }
1263 
1264 bool AMDGPUDAGToDAGISel::SelectMUBUFOffset(SDValue Addr, SDValue &SRsrc,
1265                                            SDValue &Soffset, SDValue &Offset
1266                                            ) const {
1267   SDValue GLC, SLC, TFE;
1268 
1269   return SelectMUBUFOffset(Addr, SRsrc, Soffset, Offset, GLC, SLC, TFE);
1270 }
1271 bool AMDGPUDAGToDAGISel::SelectMUBUFOffset(SDValue Addr, SDValue &SRsrc,
1272                                            SDValue &Soffset, SDValue &Offset,
1273                                            SDValue &SLC) const {
1274   SDValue GLC, TFE;
1275 
1276   return SelectMUBUFOffset(Addr, SRsrc, Soffset, Offset, GLC, SLC, TFE);
1277 }
1278 
1279 template <bool IsSigned>
1280 bool AMDGPUDAGToDAGISel::SelectFlatOffset(SDValue Addr,
1281                                           SDValue &VAddr,
1282                                           SDValue &Offset,
1283                                           SDValue &SLC) const {
1284   int64_t OffsetVal = 0;
1285 
1286   if (Subtarget->hasFlatInstOffsets() &&
1287       CurDAG->isBaseWithConstantOffset(Addr)) {
1288     SDValue N0 = Addr.getOperand(0);
1289     SDValue N1 = Addr.getOperand(1);
1290     int64_t COffsetVal = cast<ConstantSDNode>(N1)->getSExtValue();
1291 
1292     if ((IsSigned && isInt<13>(COffsetVal)) ||
1293         (!IsSigned && isUInt<12>(COffsetVal))) {
1294       Addr = N0;
1295       OffsetVal = COffsetVal;
1296     }
1297   }
1298 
1299   VAddr = Addr;
1300   Offset = CurDAG->getTargetConstant(OffsetVal, SDLoc(), MVT::i16);
1301   SLC = CurDAG->getTargetConstant(0, SDLoc(), MVT::i1);
1302 
1303   return true;
1304 }
1305 
1306 bool AMDGPUDAGToDAGISel::SelectFlatAtomic(SDValue Addr,
1307                                           SDValue &VAddr,
1308                                           SDValue &Offset,
1309                                           SDValue &SLC) const {
1310   return SelectFlatOffset<false>(Addr, VAddr, Offset, SLC);
1311 }
1312 
1313 bool AMDGPUDAGToDAGISel::SelectFlatAtomicSigned(SDValue Addr,
1314                                           SDValue &VAddr,
1315                                           SDValue &Offset,
1316                                           SDValue &SLC) const {
1317   return SelectFlatOffset<true>(Addr, VAddr, Offset, SLC);
1318 }
1319 
1320 bool AMDGPUDAGToDAGISel::SelectSMRDOffset(SDValue ByteOffsetNode,
1321                                           SDValue &Offset, bool &Imm) const {
1322 
1323   // FIXME: Handle non-constant offsets.
1324   ConstantSDNode *C = dyn_cast<ConstantSDNode>(ByteOffsetNode);
1325   if (!C)
1326     return false;
1327 
1328   SDLoc SL(ByteOffsetNode);
1329   GCNSubtarget::Generation Gen = Subtarget->getGeneration();
1330   int64_t ByteOffset = C->getSExtValue();
1331   int64_t EncodedOffset = AMDGPU::getSMRDEncodedOffset(*Subtarget, ByteOffset);
1332 
1333   if (AMDGPU::isLegalSMRDImmOffset(*Subtarget, ByteOffset)) {
1334     Offset = CurDAG->getTargetConstant(EncodedOffset, SL, MVT::i32);
1335     Imm = true;
1336     return true;
1337   }
1338 
1339   if (!isUInt<32>(EncodedOffset) || !isUInt<32>(ByteOffset))
1340     return false;
1341 
1342   if (Gen == AMDGPUSubtarget::SEA_ISLANDS && isUInt<32>(EncodedOffset)) {
1343     // 32-bit Immediates are supported on Sea Islands.
1344     Offset = CurDAG->getTargetConstant(EncodedOffset, SL, MVT::i32);
1345   } else {
1346     SDValue C32Bit = CurDAG->getTargetConstant(ByteOffset, SL, MVT::i32);
1347     Offset = SDValue(CurDAG->getMachineNode(AMDGPU::S_MOV_B32, SL, MVT::i32,
1348                                             C32Bit), 0);
1349   }
1350   Imm = false;
1351   return true;
1352 }
1353 
1354 SDValue AMDGPUDAGToDAGISel::Expand32BitAddress(SDValue Addr) const {
1355   if (Addr.getValueType() != MVT::i32)
1356     return Addr;
1357 
1358   // Zero-extend a 32-bit address.
1359   SDLoc SL(Addr);
1360 
1361   const MachineFunction &MF = CurDAG->getMachineFunction();
1362   const SIMachineFunctionInfo *Info = MF.getInfo<SIMachineFunctionInfo>();
1363   unsigned AddrHiVal = Info->get32BitAddressHighBits();
1364   SDValue AddrHi = CurDAG->getTargetConstant(AddrHiVal, SL, MVT::i32);
1365 
1366   const SDValue Ops[] = {
1367     CurDAG->getTargetConstant(AMDGPU::SReg_64_XEXECRegClassID, SL, MVT::i32),
1368     Addr,
1369     CurDAG->getTargetConstant(AMDGPU::sub0, SL, MVT::i32),
1370     SDValue(CurDAG->getMachineNode(AMDGPU::S_MOV_B32, SL, MVT::i32, AddrHi),
1371             0),
1372     CurDAG->getTargetConstant(AMDGPU::sub1, SL, MVT::i32),
1373   };
1374 
1375   return SDValue(CurDAG->getMachineNode(AMDGPU::REG_SEQUENCE, SL, MVT::i64,
1376                                         Ops), 0);
1377 }
1378 
1379 bool AMDGPUDAGToDAGISel::SelectSMRD(SDValue Addr, SDValue &SBase,
1380                                      SDValue &Offset, bool &Imm) const {
1381   SDLoc SL(Addr);
1382 
1383   // A 32-bit (address + offset) should not cause unsigned 32-bit integer
1384   // wraparound, because s_load instructions perform the addition in 64 bits.
1385   if ((Addr.getValueType() != MVT::i32 ||
1386        Addr->getFlags().hasNoUnsignedWrap()) &&
1387       CurDAG->isBaseWithConstantOffset(Addr)) {
1388     SDValue N0 = Addr.getOperand(0);
1389     SDValue N1 = Addr.getOperand(1);
1390 
1391     if (SelectSMRDOffset(N1, Offset, Imm)) {
1392       SBase = Expand32BitAddress(N0);
1393       return true;
1394     }
1395   }
1396   SBase = Expand32BitAddress(Addr);
1397   Offset = CurDAG->getTargetConstant(0, SL, MVT::i32);
1398   Imm = true;
1399   return true;
1400 }
1401 
1402 bool AMDGPUDAGToDAGISel::SelectSMRDImm(SDValue Addr, SDValue &SBase,
1403                                        SDValue &Offset) const {
1404   bool Imm;
1405   return SelectSMRD(Addr, SBase, Offset, Imm) && Imm;
1406 }
1407 
1408 bool AMDGPUDAGToDAGISel::SelectSMRDImm32(SDValue Addr, SDValue &SBase,
1409                                          SDValue &Offset) const {
1410 
1411   if (Subtarget->getGeneration() != AMDGPUSubtarget::SEA_ISLANDS)
1412     return false;
1413 
1414   bool Imm;
1415   if (!SelectSMRD(Addr, SBase, Offset, Imm))
1416     return false;
1417 
1418   return !Imm && isa<ConstantSDNode>(Offset);
1419 }
1420 
1421 bool AMDGPUDAGToDAGISel::SelectSMRDSgpr(SDValue Addr, SDValue &SBase,
1422                                         SDValue &Offset) const {
1423   bool Imm;
1424   return SelectSMRD(Addr, SBase, Offset, Imm) && !Imm &&
1425          !isa<ConstantSDNode>(Offset);
1426 }
1427 
1428 bool AMDGPUDAGToDAGISel::SelectSMRDBufferImm(SDValue Addr,
1429                                              SDValue &Offset) const {
1430   bool Imm;
1431   return SelectSMRDOffset(Addr, Offset, Imm) && Imm;
1432 }
1433 
1434 bool AMDGPUDAGToDAGISel::SelectSMRDBufferImm32(SDValue Addr,
1435                                                SDValue &Offset) const {
1436   if (Subtarget->getGeneration() != AMDGPUSubtarget::SEA_ISLANDS)
1437     return false;
1438 
1439   bool Imm;
1440   if (!SelectSMRDOffset(Addr, Offset, Imm))
1441     return false;
1442 
1443   return !Imm && isa<ConstantSDNode>(Offset);
1444 }
1445 
1446 bool AMDGPUDAGToDAGISel::SelectMOVRELOffset(SDValue Index,
1447                                             SDValue &Base,
1448                                             SDValue &Offset) const {
1449   SDLoc DL(Index);
1450 
1451   if (CurDAG->isBaseWithConstantOffset(Index)) {
1452     SDValue N0 = Index.getOperand(0);
1453     SDValue N1 = Index.getOperand(1);
1454     ConstantSDNode *C1 = cast<ConstantSDNode>(N1);
1455 
1456     // (add n0, c0)
1457     Base = N0;
1458     Offset = CurDAG->getTargetConstant(C1->getZExtValue(), DL, MVT::i32);
1459     return true;
1460   }
1461 
1462   if (isa<ConstantSDNode>(Index))
1463     return false;
1464 
1465   Base = Index;
1466   Offset = CurDAG->getTargetConstant(0, DL, MVT::i32);
1467   return true;
1468 }
1469 
1470 SDNode *AMDGPUDAGToDAGISel::getS_BFE(unsigned Opcode, const SDLoc &DL,
1471                                      SDValue Val, uint32_t Offset,
1472                                      uint32_t Width) {
1473   // Transformation function, pack the offset and width of a BFE into
1474   // the format expected by the S_BFE_I32 / S_BFE_U32. In the second
1475   // source, bits [5:0] contain the offset and bits [22:16] the width.
1476   uint32_t PackedVal = Offset | (Width << 16);
1477   SDValue PackedConst = CurDAG->getTargetConstant(PackedVal, DL, MVT::i32);
1478 
1479   return CurDAG->getMachineNode(Opcode, DL, MVT::i32, Val, PackedConst);
1480 }
1481 
1482 void AMDGPUDAGToDAGISel::SelectS_BFEFromShifts(SDNode *N) {
1483   // "(a << b) srl c)" ---> "BFE_U32 a, (c-b), (32-c)
1484   // "(a << b) sra c)" ---> "BFE_I32 a, (c-b), (32-c)
1485   // Predicate: 0 < b <= c < 32
1486 
1487   const SDValue &Shl = N->getOperand(0);
1488   ConstantSDNode *B = dyn_cast<ConstantSDNode>(Shl->getOperand(1));
1489   ConstantSDNode *C = dyn_cast<ConstantSDNode>(N->getOperand(1));
1490 
1491   if (B && C) {
1492     uint32_t BVal = B->getZExtValue();
1493     uint32_t CVal = C->getZExtValue();
1494 
1495     if (0 < BVal && BVal <= CVal && CVal < 32) {
1496       bool Signed = N->getOpcode() == ISD::SRA;
1497       unsigned Opcode = Signed ? AMDGPU::S_BFE_I32 : AMDGPU::S_BFE_U32;
1498 
1499       ReplaceNode(N, getS_BFE(Opcode, SDLoc(N), Shl.getOperand(0), CVal - BVal,
1500                               32 - CVal));
1501       return;
1502     }
1503   }
1504   SelectCode(N);
1505 }
1506 
1507 void AMDGPUDAGToDAGISel::SelectS_BFE(SDNode *N) {
1508   switch (N->getOpcode()) {
1509   case ISD::AND:
1510     if (N->getOperand(0).getOpcode() == ISD::SRL) {
1511       // "(a srl b) & mask" ---> "BFE_U32 a, b, popcount(mask)"
1512       // Predicate: isMask(mask)
1513       const SDValue &Srl = N->getOperand(0);
1514       ConstantSDNode *Shift = dyn_cast<ConstantSDNode>(Srl.getOperand(1));
1515       ConstantSDNode *Mask = dyn_cast<ConstantSDNode>(N->getOperand(1));
1516 
1517       if (Shift && Mask) {
1518         uint32_t ShiftVal = Shift->getZExtValue();
1519         uint32_t MaskVal = Mask->getZExtValue();
1520 
1521         if (isMask_32(MaskVal)) {
1522           uint32_t WidthVal = countPopulation(MaskVal);
1523 
1524           ReplaceNode(N, getS_BFE(AMDGPU::S_BFE_U32, SDLoc(N),
1525                                   Srl.getOperand(0), ShiftVal, WidthVal));
1526           return;
1527         }
1528       }
1529     }
1530     break;
1531   case ISD::SRL:
1532     if (N->getOperand(0).getOpcode() == ISD::AND) {
1533       // "(a & mask) srl b)" ---> "BFE_U32 a, b, popcount(mask >> b)"
1534       // Predicate: isMask(mask >> b)
1535       const SDValue &And = N->getOperand(0);
1536       ConstantSDNode *Shift = dyn_cast<ConstantSDNode>(N->getOperand(1));
1537       ConstantSDNode *Mask = dyn_cast<ConstantSDNode>(And->getOperand(1));
1538 
1539       if (Shift && Mask) {
1540         uint32_t ShiftVal = Shift->getZExtValue();
1541         uint32_t MaskVal = Mask->getZExtValue() >> ShiftVal;
1542 
1543         if (isMask_32(MaskVal)) {
1544           uint32_t WidthVal = countPopulation(MaskVal);
1545 
1546           ReplaceNode(N, getS_BFE(AMDGPU::S_BFE_U32, SDLoc(N),
1547                                   And.getOperand(0), ShiftVal, WidthVal));
1548           return;
1549         }
1550       }
1551     } else if (N->getOperand(0).getOpcode() == ISD::SHL) {
1552       SelectS_BFEFromShifts(N);
1553       return;
1554     }
1555     break;
1556   case ISD::SRA:
1557     if (N->getOperand(0).getOpcode() == ISD::SHL) {
1558       SelectS_BFEFromShifts(N);
1559       return;
1560     }
1561     break;
1562 
1563   case ISD::SIGN_EXTEND_INREG: {
1564     // sext_inreg (srl x, 16), i8 -> bfe_i32 x, 16, 8
1565     SDValue Src = N->getOperand(0);
1566     if (Src.getOpcode() != ISD::SRL)
1567       break;
1568 
1569     const ConstantSDNode *Amt = dyn_cast<ConstantSDNode>(Src.getOperand(1));
1570     if (!Amt)
1571       break;
1572 
1573     unsigned Width = cast<VTSDNode>(N->getOperand(1))->getVT().getSizeInBits();
1574     ReplaceNode(N, getS_BFE(AMDGPU::S_BFE_I32, SDLoc(N), Src.getOperand(0),
1575                             Amt->getZExtValue(), Width));
1576     return;
1577   }
1578   }
1579 
1580   SelectCode(N);
1581 }
1582 
1583 bool AMDGPUDAGToDAGISel::isCBranchSCC(const SDNode *N) const {
1584   assert(N->getOpcode() == ISD::BRCOND);
1585   if (!N->hasOneUse())
1586     return false;
1587 
1588   SDValue Cond = N->getOperand(1);
1589   if (Cond.getOpcode() == ISD::CopyToReg)
1590     Cond = Cond.getOperand(2);
1591 
1592   if (Cond.getOpcode() != ISD::SETCC || !Cond.hasOneUse())
1593     return false;
1594 
1595   MVT VT = Cond.getOperand(0).getSimpleValueType();
1596   if (VT == MVT::i32)
1597     return true;
1598 
1599   if (VT == MVT::i64) {
1600     auto ST = static_cast<const GCNSubtarget *>(Subtarget);
1601 
1602     ISD::CondCode CC = cast<CondCodeSDNode>(Cond.getOperand(2))->get();
1603     return (CC == ISD::SETEQ || CC == ISD::SETNE) && ST->hasScalarCompareEq64();
1604   }
1605 
1606   return false;
1607 }
1608 
1609 void AMDGPUDAGToDAGISel::SelectBRCOND(SDNode *N) {
1610   SDValue Cond = N->getOperand(1);
1611 
1612   if (Cond.isUndef()) {
1613     CurDAG->SelectNodeTo(N, AMDGPU::SI_BR_UNDEF, MVT::Other,
1614                          N->getOperand(2), N->getOperand(0));
1615     return;
1616   }
1617 
1618   bool UseSCCBr = isCBranchSCC(N) && isUniformBr(N);
1619   unsigned BrOp = UseSCCBr ? AMDGPU::S_CBRANCH_SCC1 : AMDGPU::S_CBRANCH_VCCNZ;
1620   unsigned CondReg = UseSCCBr ? AMDGPU::SCC : AMDGPU::VCC;
1621   SDLoc SL(N);
1622 
1623   if (!UseSCCBr) {
1624     // This is the case that we are selecting to S_CBRANCH_VCCNZ.  We have not
1625     // analyzed what generates the vcc value, so we do not know whether vcc
1626     // bits for disabled lanes are 0.  Thus we need to mask out bits for
1627     // disabled lanes.
1628     //
1629     // For the case that we select S_CBRANCH_SCC1 and it gets
1630     // changed to S_CBRANCH_VCCNZ in SIFixSGPRCopies, SIFixSGPRCopies calls
1631     // SIInstrInfo::moveToVALU which inserts the S_AND).
1632     //
1633     // We could add an analysis of what generates the vcc value here and omit
1634     // the S_AND when is unnecessary. But it would be better to add a separate
1635     // pass after SIFixSGPRCopies to do the unnecessary S_AND removal, so it
1636     // catches both cases.
1637     Cond = SDValue(CurDAG->getMachineNode(AMDGPU::S_AND_B64, SL, MVT::i1,
1638                                CurDAG->getRegister(AMDGPU::EXEC, MVT::i1),
1639                                Cond),
1640                    0);
1641   }
1642 
1643   SDValue VCC = CurDAG->getCopyToReg(N->getOperand(0), SL, CondReg, Cond);
1644   CurDAG->SelectNodeTo(N, BrOp, MVT::Other,
1645                        N->getOperand(2), // Basic Block
1646                        VCC.getValue(0));
1647 }
1648 
1649 void AMDGPUDAGToDAGISel::SelectFMAD_FMA(SDNode *N) {
1650   MVT VT = N->getSimpleValueType(0);
1651   bool IsFMA = N->getOpcode() == ISD::FMA;
1652   if (VT != MVT::f32 || (!Subtarget->hasMadMixInsts() &&
1653                          !Subtarget->hasFmaMixInsts()) ||
1654       ((IsFMA && Subtarget->hasMadMixInsts()) ||
1655        (!IsFMA && Subtarget->hasFmaMixInsts()))) {
1656     SelectCode(N);
1657     return;
1658   }
1659 
1660   SDValue Src0 = N->getOperand(0);
1661   SDValue Src1 = N->getOperand(1);
1662   SDValue Src2 = N->getOperand(2);
1663   unsigned Src0Mods, Src1Mods, Src2Mods;
1664 
1665   // Avoid using v_mad_mix_f32/v_fma_mix_f32 unless there is actually an operand
1666   // using the conversion from f16.
1667   bool Sel0 = SelectVOP3PMadMixModsImpl(Src0, Src0, Src0Mods);
1668   bool Sel1 = SelectVOP3PMadMixModsImpl(Src1, Src1, Src1Mods);
1669   bool Sel2 = SelectVOP3PMadMixModsImpl(Src2, Src2, Src2Mods);
1670 
1671   assert((IsFMA || !Subtarget->hasFP32Denormals()) &&
1672          "fmad selected with denormals enabled");
1673   // TODO: We can select this with f32 denormals enabled if all the sources are
1674   // converted from f16 (in which case fmad isn't legal).
1675 
1676   if (Sel0 || Sel1 || Sel2) {
1677     // For dummy operands.
1678     SDValue Zero = CurDAG->getTargetConstant(0, SDLoc(), MVT::i32);
1679     SDValue Ops[] = {
1680       CurDAG->getTargetConstant(Src0Mods, SDLoc(), MVT::i32), Src0,
1681       CurDAG->getTargetConstant(Src1Mods, SDLoc(), MVT::i32), Src1,
1682       CurDAG->getTargetConstant(Src2Mods, SDLoc(), MVT::i32), Src2,
1683       CurDAG->getTargetConstant(0, SDLoc(), MVT::i1),
1684       Zero, Zero
1685     };
1686 
1687     CurDAG->SelectNodeTo(N,
1688                          IsFMA ? AMDGPU::V_FMA_MIX_F32 : AMDGPU::V_MAD_MIX_F32,
1689                          MVT::f32, Ops);
1690   } else {
1691     SelectCode(N);
1692   }
1693 }
1694 
1695 // This is here because there isn't a way to use the generated sub0_sub1 as the
1696 // subreg index to EXTRACT_SUBREG in tablegen.
1697 void AMDGPUDAGToDAGISel::SelectATOMIC_CMP_SWAP(SDNode *N) {
1698   MemSDNode *Mem = cast<MemSDNode>(N);
1699   unsigned AS = Mem->getAddressSpace();
1700   if (AS == AMDGPUAS::FLAT_ADDRESS) {
1701     SelectCode(N);
1702     return;
1703   }
1704 
1705   MVT VT = N->getSimpleValueType(0);
1706   bool Is32 = (VT == MVT::i32);
1707   SDLoc SL(N);
1708 
1709   MachineSDNode *CmpSwap = nullptr;
1710   if (Subtarget->hasAddr64()) {
1711     SDValue SRsrc, VAddr, SOffset, Offset, SLC;
1712 
1713     if (SelectMUBUFAddr64(Mem->getBasePtr(), SRsrc, VAddr, SOffset, Offset, SLC)) {
1714       unsigned Opcode = Is32 ? AMDGPU::BUFFER_ATOMIC_CMPSWAP_ADDR64_RTN :
1715         AMDGPU::BUFFER_ATOMIC_CMPSWAP_X2_ADDR64_RTN;
1716       SDValue CmpVal = Mem->getOperand(2);
1717 
1718       // XXX - Do we care about glue operands?
1719 
1720       SDValue Ops[] = {
1721         CmpVal, VAddr, SRsrc, SOffset, Offset, SLC, Mem->getChain()
1722       };
1723 
1724       CmpSwap = CurDAG->getMachineNode(Opcode, SL, Mem->getVTList(), Ops);
1725     }
1726   }
1727 
1728   if (!CmpSwap) {
1729     SDValue SRsrc, SOffset, Offset, SLC;
1730     if (SelectMUBUFOffset(Mem->getBasePtr(), SRsrc, SOffset, Offset, SLC)) {
1731       unsigned Opcode = Is32 ? AMDGPU::BUFFER_ATOMIC_CMPSWAP_OFFSET_RTN :
1732         AMDGPU::BUFFER_ATOMIC_CMPSWAP_X2_OFFSET_RTN;
1733 
1734       SDValue CmpVal = Mem->getOperand(2);
1735       SDValue Ops[] = {
1736         CmpVal, SRsrc, SOffset, Offset, SLC, Mem->getChain()
1737       };
1738 
1739       CmpSwap = CurDAG->getMachineNode(Opcode, SL, Mem->getVTList(), Ops);
1740     }
1741   }
1742 
1743   if (!CmpSwap) {
1744     SelectCode(N);
1745     return;
1746   }
1747 
1748   MachineMemOperand *MMO = Mem->getMemOperand();
1749   CurDAG->setNodeMemRefs(CmpSwap, {MMO});
1750 
1751   unsigned SubReg = Is32 ? AMDGPU::sub0 : AMDGPU::sub0_sub1;
1752   SDValue Extract
1753     = CurDAG->getTargetExtractSubreg(SubReg, SL, VT, SDValue(CmpSwap, 0));
1754 
1755   ReplaceUses(SDValue(N, 0), Extract);
1756   ReplaceUses(SDValue(N, 1), SDValue(CmpSwap, 1));
1757   CurDAG->RemoveDeadNode(N);
1758 }
1759 
1760 bool AMDGPUDAGToDAGISel::SelectVOP3ModsImpl(SDValue In, SDValue &Src,
1761                                             unsigned &Mods) const {
1762   Mods = 0;
1763   Src = In;
1764 
1765   if (Src.getOpcode() == ISD::FNEG) {
1766     Mods |= SISrcMods::NEG;
1767     Src = Src.getOperand(0);
1768   }
1769 
1770   if (Src.getOpcode() == ISD::FABS) {
1771     Mods |= SISrcMods::ABS;
1772     Src = Src.getOperand(0);
1773   }
1774 
1775   return true;
1776 }
1777 
1778 bool AMDGPUDAGToDAGISel::SelectVOP3Mods(SDValue In, SDValue &Src,
1779                                         SDValue &SrcMods) const {
1780   unsigned Mods;
1781   if (SelectVOP3ModsImpl(In, Src, Mods)) {
1782     SrcMods = CurDAG->getTargetConstant(Mods, SDLoc(In), MVT::i32);
1783     return true;
1784   }
1785 
1786   return false;
1787 }
1788 
1789 bool AMDGPUDAGToDAGISel::SelectVOP3Mods_NNaN(SDValue In, SDValue &Src,
1790                                              SDValue &SrcMods) const {
1791   SelectVOP3Mods(In, Src, SrcMods);
1792   return isNoNanSrc(Src);
1793 }
1794 
1795 bool AMDGPUDAGToDAGISel::SelectVOP3NoMods(SDValue In, SDValue &Src) const {
1796   if (In.getOpcode() == ISD::FABS || In.getOpcode() == ISD::FNEG)
1797     return false;
1798 
1799   Src = In;
1800   return true;
1801 }
1802 
1803 bool AMDGPUDAGToDAGISel::SelectVOP3Mods0(SDValue In, SDValue &Src,
1804                                          SDValue &SrcMods, SDValue &Clamp,
1805                                          SDValue &Omod) const {
1806   SDLoc DL(In);
1807   Clamp = CurDAG->getTargetConstant(0, DL, MVT::i1);
1808   Omod = CurDAG->getTargetConstant(0, DL, MVT::i1);
1809 
1810   return SelectVOP3Mods(In, Src, SrcMods);
1811 }
1812 
1813 bool AMDGPUDAGToDAGISel::SelectVOP3Mods0Clamp0OMod(SDValue In, SDValue &Src,
1814                                                    SDValue &SrcMods,
1815                                                    SDValue &Clamp,
1816                                                    SDValue &Omod) const {
1817   Clamp = Omod = CurDAG->getTargetConstant(0, SDLoc(In), MVT::i32);
1818   return SelectVOP3Mods(In, Src, SrcMods);
1819 }
1820 
1821 bool AMDGPUDAGToDAGISel::SelectVOP3OMods(SDValue In, SDValue &Src,
1822                                          SDValue &Clamp, SDValue &Omod) const {
1823   Src = In;
1824 
1825   SDLoc DL(In);
1826   Clamp = CurDAG->getTargetConstant(0, DL, MVT::i1);
1827   Omod = CurDAG->getTargetConstant(0, DL, MVT::i1);
1828 
1829   return true;
1830 }
1831 
1832 static SDValue stripBitcast(SDValue Val) {
1833   return Val.getOpcode() == ISD::BITCAST ? Val.getOperand(0) : Val;
1834 }
1835 
1836 // Figure out if this is really an extract of the high 16-bits of a dword.
1837 static bool isExtractHiElt(SDValue In, SDValue &Out) {
1838   In = stripBitcast(In);
1839   if (In.getOpcode() != ISD::TRUNCATE)
1840     return false;
1841 
1842   SDValue Srl = In.getOperand(0);
1843   if (Srl.getOpcode() == ISD::SRL) {
1844     if (ConstantSDNode *ShiftAmt = dyn_cast<ConstantSDNode>(Srl.getOperand(1))) {
1845       if (ShiftAmt->getZExtValue() == 16) {
1846         Out = stripBitcast(Srl.getOperand(0));
1847         return true;
1848       }
1849     }
1850   }
1851 
1852   return false;
1853 }
1854 
1855 // Look through operations that obscure just looking at the low 16-bits of the
1856 // same register.
1857 static SDValue stripExtractLoElt(SDValue In) {
1858   if (In.getOpcode() == ISD::TRUNCATE) {
1859     SDValue Src = In.getOperand(0);
1860     if (Src.getValueType().getSizeInBits() == 32)
1861       return stripBitcast(Src);
1862   }
1863 
1864   return In;
1865 }
1866 
1867 bool AMDGPUDAGToDAGISel::SelectVOP3PMods(SDValue In, SDValue &Src,
1868                                          SDValue &SrcMods) const {
1869   unsigned Mods = 0;
1870   Src = In;
1871 
1872   if (Src.getOpcode() == ISD::FNEG) {
1873     Mods ^= (SISrcMods::NEG | SISrcMods::NEG_HI);
1874     Src = Src.getOperand(0);
1875   }
1876 
1877   if (Src.getOpcode() == ISD::BUILD_VECTOR) {
1878     unsigned VecMods = Mods;
1879 
1880     SDValue Lo = stripBitcast(Src.getOperand(0));
1881     SDValue Hi = stripBitcast(Src.getOperand(1));
1882 
1883     if (Lo.getOpcode() == ISD::FNEG) {
1884       Lo = stripBitcast(Lo.getOperand(0));
1885       Mods ^= SISrcMods::NEG;
1886     }
1887 
1888     if (Hi.getOpcode() == ISD::FNEG) {
1889       Hi = stripBitcast(Hi.getOperand(0));
1890       Mods ^= SISrcMods::NEG_HI;
1891     }
1892 
1893     if (isExtractHiElt(Lo, Lo))
1894       Mods |= SISrcMods::OP_SEL_0;
1895 
1896     if (isExtractHiElt(Hi, Hi))
1897       Mods |= SISrcMods::OP_SEL_1;
1898 
1899     Lo = stripExtractLoElt(Lo);
1900     Hi = stripExtractLoElt(Hi);
1901 
1902     if (Lo == Hi && !isInlineImmediate(Lo.getNode())) {
1903       // Really a scalar input. Just select from the low half of the register to
1904       // avoid packing.
1905 
1906       Src = Lo;
1907       SrcMods = CurDAG->getTargetConstant(Mods, SDLoc(In), MVT::i32);
1908       return true;
1909     }
1910 
1911     Mods = VecMods;
1912   }
1913 
1914   // Packed instructions do not have abs modifiers.
1915   Mods |= SISrcMods::OP_SEL_1;
1916 
1917   SrcMods = CurDAG->getTargetConstant(Mods, SDLoc(In), MVT::i32);
1918   return true;
1919 }
1920 
1921 bool AMDGPUDAGToDAGISel::SelectVOP3PMods0(SDValue In, SDValue &Src,
1922                                           SDValue &SrcMods,
1923                                           SDValue &Clamp) const {
1924   SDLoc SL(In);
1925 
1926   // FIXME: Handle clamp and op_sel
1927   Clamp = CurDAG->getTargetConstant(0, SL, MVT::i32);
1928 
1929   return SelectVOP3PMods(In, Src, SrcMods);
1930 }
1931 
1932 bool AMDGPUDAGToDAGISel::SelectVOP3OpSel(SDValue In, SDValue &Src,
1933                                          SDValue &SrcMods) const {
1934   Src = In;
1935   // FIXME: Handle op_sel
1936   SrcMods = CurDAG->getTargetConstant(0, SDLoc(In), MVT::i32);
1937   return true;
1938 }
1939 
1940 bool AMDGPUDAGToDAGISel::SelectVOP3OpSel0(SDValue In, SDValue &Src,
1941                                           SDValue &SrcMods,
1942                                           SDValue &Clamp) const {
1943   SDLoc SL(In);
1944 
1945   // FIXME: Handle clamp
1946   Clamp = CurDAG->getTargetConstant(0, SL, MVT::i32);
1947 
1948   return SelectVOP3OpSel(In, Src, SrcMods);
1949 }
1950 
1951 bool AMDGPUDAGToDAGISel::SelectVOP3OpSelMods(SDValue In, SDValue &Src,
1952                                              SDValue &SrcMods) const {
1953   // FIXME: Handle op_sel
1954   return SelectVOP3Mods(In, Src, SrcMods);
1955 }
1956 
1957 bool AMDGPUDAGToDAGISel::SelectVOP3OpSelMods0(SDValue In, SDValue &Src,
1958                                               SDValue &SrcMods,
1959                                               SDValue &Clamp) const {
1960   SDLoc SL(In);
1961 
1962   // FIXME: Handle clamp
1963   Clamp = CurDAG->getTargetConstant(0, SL, MVT::i32);
1964 
1965   return SelectVOP3OpSelMods(In, Src, SrcMods);
1966 }
1967 
1968 // The return value is not whether the match is possible (which it always is),
1969 // but whether or not it a conversion is really used.
1970 bool AMDGPUDAGToDAGISel::SelectVOP3PMadMixModsImpl(SDValue In, SDValue &Src,
1971                                                    unsigned &Mods) const {
1972   Mods = 0;
1973   SelectVOP3ModsImpl(In, Src, Mods);
1974 
1975   if (Src.getOpcode() == ISD::FP_EXTEND) {
1976     Src = Src.getOperand(0);
1977     assert(Src.getValueType() == MVT::f16);
1978     Src = stripBitcast(Src);
1979 
1980     // Be careful about folding modifiers if we already have an abs. fneg is
1981     // applied last, so we don't want to apply an earlier fneg.
1982     if ((Mods & SISrcMods::ABS) == 0) {
1983       unsigned ModsTmp;
1984       SelectVOP3ModsImpl(Src, Src, ModsTmp);
1985 
1986       if ((ModsTmp & SISrcMods::NEG) != 0)
1987         Mods ^= SISrcMods::NEG;
1988 
1989       if ((ModsTmp & SISrcMods::ABS) != 0)
1990         Mods |= SISrcMods::ABS;
1991     }
1992 
1993     // op_sel/op_sel_hi decide the source type and source.
1994     // If the source's op_sel_hi is set, it indicates to do a conversion from fp16.
1995     // If the sources's op_sel is set, it picks the high half of the source
1996     // register.
1997 
1998     Mods |= SISrcMods::OP_SEL_1;
1999     if (isExtractHiElt(Src, Src)) {
2000       Mods |= SISrcMods::OP_SEL_0;
2001 
2002       // TODO: Should we try to look for neg/abs here?
2003     }
2004 
2005     return true;
2006   }
2007 
2008   return false;
2009 }
2010 
2011 bool AMDGPUDAGToDAGISel::SelectVOP3PMadMixMods(SDValue In, SDValue &Src,
2012                                                SDValue &SrcMods) const {
2013   unsigned Mods = 0;
2014   SelectVOP3PMadMixModsImpl(In, Src, Mods);
2015   SrcMods = CurDAG->getTargetConstant(Mods, SDLoc(In), MVT::i32);
2016   return true;
2017 }
2018 
2019 // TODO: Can we identify things like v_mad_mixhi_f16?
2020 bool AMDGPUDAGToDAGISel::SelectHi16Elt(SDValue In, SDValue &Src) const {
2021   if (In.isUndef()) {
2022     Src = In;
2023     return true;
2024   }
2025 
2026   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(In)) {
2027     SDLoc SL(In);
2028     SDValue K = CurDAG->getTargetConstant(C->getZExtValue() << 16, SL, MVT::i32);
2029     MachineSDNode *MovK = CurDAG->getMachineNode(AMDGPU::V_MOV_B32_e32,
2030                                                  SL, MVT::i32, K);
2031     Src = SDValue(MovK, 0);
2032     return true;
2033   }
2034 
2035   if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(In)) {
2036     SDLoc SL(In);
2037     SDValue K = CurDAG->getTargetConstant(
2038       C->getValueAPF().bitcastToAPInt().getZExtValue() << 16, SL, MVT::i32);
2039     MachineSDNode *MovK = CurDAG->getMachineNode(AMDGPU::V_MOV_B32_e32,
2040                                                  SL, MVT::i32, K);
2041     Src = SDValue(MovK, 0);
2042     return true;
2043   }
2044 
2045   return isExtractHiElt(In, Src);
2046 }
2047 
2048 bool AMDGPUDAGToDAGISel::isVGPRImm(const SDNode * N) const {
2049   if (Subtarget->getGeneration() < AMDGPUSubtarget::SOUTHERN_ISLANDS) {
2050     return false;
2051   }
2052   const SIRegisterInfo *SIRI =
2053     static_cast<const SIRegisterInfo *>(Subtarget->getRegisterInfo());
2054   const SIInstrInfo * SII =
2055     static_cast<const SIInstrInfo *>(Subtarget->getInstrInfo());
2056 
2057   unsigned Limit = 0;
2058   bool AllUsesAcceptSReg = true;
2059   for (SDNode::use_iterator U = N->use_begin(), E = SDNode::use_end();
2060     Limit < 10 && U != E; ++U, ++Limit) {
2061     const TargetRegisterClass *RC = getOperandRegClass(*U, U.getOperandNo());
2062 
2063     // If the register class is unknown, it could be an unknown
2064     // register class that needs to be an SGPR, e.g. an inline asm
2065     // constraint
2066     if (!RC || SIRI->isSGPRClass(RC))
2067       return false;
2068 
2069     if (RC != &AMDGPU::VS_32RegClass) {
2070       AllUsesAcceptSReg = false;
2071       SDNode * User = *U;
2072       if (User->isMachineOpcode()) {
2073         unsigned Opc = User->getMachineOpcode();
2074         MCInstrDesc Desc = SII->get(Opc);
2075         if (Desc.isCommutable()) {
2076           unsigned OpIdx = Desc.getNumDefs() + U.getOperandNo();
2077           unsigned CommuteIdx1 = TargetInstrInfo::CommuteAnyOperandIndex;
2078           if (SII->findCommutedOpIndices(Desc, OpIdx, CommuteIdx1)) {
2079             unsigned CommutedOpNo = CommuteIdx1 - Desc.getNumDefs();
2080             const TargetRegisterClass *CommutedRC = getOperandRegClass(*U, CommutedOpNo);
2081             if (CommutedRC == &AMDGPU::VS_32RegClass)
2082               AllUsesAcceptSReg = true;
2083           }
2084         }
2085       }
2086       // If "AllUsesAcceptSReg == false" so far we haven't suceeded
2087       // commuting current user. This means have at least one use
2088       // that strictly require VGPR. Thus, we will not attempt to commute
2089       // other user instructions.
2090       if (!AllUsesAcceptSReg)
2091         break;
2092     }
2093   }
2094   return !AllUsesAcceptSReg && (Limit < 10);
2095 }
2096 
2097 bool AMDGPUDAGToDAGISel::isUniformLoad(const SDNode * N) const {
2098   auto Ld = cast<LoadSDNode>(N);
2099 
2100   return Ld->getAlignment() >= 4 &&
2101         (
2102           (
2103             (
2104               Ld->getAddressSpace() == AMDGPUAS::CONSTANT_ADDRESS       ||
2105               Ld->getAddressSpace() == AMDGPUAS::CONSTANT_ADDRESS_32BIT
2106             )
2107             &&
2108             !N->isDivergent()
2109           )
2110           ||
2111           (
2112             Subtarget->getScalarizeGlobalBehavior() &&
2113             Ld->getAddressSpace() == AMDGPUAS::GLOBAL_ADDRESS &&
2114             !Ld->isVolatile() &&
2115             !N->isDivergent() &&
2116             static_cast<const SITargetLowering *>(
2117               getTargetLowering())->isMemOpHasNoClobberedMemOperand(N)
2118           )
2119         );
2120 }
2121 
2122 void AMDGPUDAGToDAGISel::PostprocessISelDAG() {
2123   const AMDGPUTargetLowering& Lowering =
2124     *static_cast<const AMDGPUTargetLowering*>(getTargetLowering());
2125   bool IsModified = false;
2126   do {
2127     IsModified = false;
2128 
2129     // Go over all selected nodes and try to fold them a bit more
2130     SelectionDAG::allnodes_iterator Position = CurDAG->allnodes_begin();
2131     while (Position != CurDAG->allnodes_end()) {
2132       SDNode *Node = &*Position++;
2133       MachineSDNode *MachineNode = dyn_cast<MachineSDNode>(Node);
2134       if (!MachineNode)
2135         continue;
2136 
2137       SDNode *ResNode = Lowering.PostISelFolding(MachineNode, *CurDAG);
2138       if (ResNode != Node) {
2139         if (ResNode)
2140           ReplaceUses(Node, ResNode);
2141         IsModified = true;
2142       }
2143     }
2144     CurDAG->RemoveDeadNodes();
2145   } while (IsModified);
2146 }
2147 
2148 bool R600DAGToDAGISel::runOnMachineFunction(MachineFunction &MF) {
2149   Subtarget = &MF.getSubtarget<R600Subtarget>();
2150   return SelectionDAGISel::runOnMachineFunction(MF);
2151 }
2152 
2153 bool R600DAGToDAGISel::isConstantLoad(const MemSDNode *N, int CbId) const {
2154   if (!N->readMem())
2155     return false;
2156   if (CbId == -1)
2157     return N->getAddressSpace() == AMDGPUAS::CONSTANT_ADDRESS ||
2158            N->getAddressSpace() == AMDGPUAS::CONSTANT_ADDRESS_32BIT;
2159 
2160   return N->getAddressSpace() == AMDGPUAS::CONSTANT_BUFFER_0 + CbId;
2161 }
2162 
2163 bool R600DAGToDAGISel::SelectGlobalValueConstantOffset(SDValue Addr,
2164                                                          SDValue& IntPtr) {
2165   if (ConstantSDNode *Cst = dyn_cast<ConstantSDNode>(Addr)) {
2166     IntPtr = CurDAG->getIntPtrConstant(Cst->getZExtValue() / 4, SDLoc(Addr),
2167                                        true);
2168     return true;
2169   }
2170   return false;
2171 }
2172 
2173 bool R600DAGToDAGISel::SelectGlobalValueVariableOffset(SDValue Addr,
2174     SDValue& BaseReg, SDValue &Offset) {
2175   if (!isa<ConstantSDNode>(Addr)) {
2176     BaseReg = Addr;
2177     Offset = CurDAG->getIntPtrConstant(0, SDLoc(Addr), true);
2178     return true;
2179   }
2180   return false;
2181 }
2182 
2183 void R600DAGToDAGISel::Select(SDNode *N) {
2184   unsigned int Opc = N->getOpcode();
2185   if (N->isMachineOpcode()) {
2186     N->setNodeId(-1);
2187     return;   // Already selected.
2188   }
2189 
2190   switch (Opc) {
2191   default: break;
2192   case AMDGPUISD::BUILD_VERTICAL_VECTOR:
2193   case ISD::SCALAR_TO_VECTOR:
2194   case ISD::BUILD_VECTOR: {
2195     EVT VT = N->getValueType(0);
2196     unsigned NumVectorElts = VT.getVectorNumElements();
2197     unsigned RegClassID;
2198     // BUILD_VECTOR was lowered into an IMPLICIT_DEF + 4 INSERT_SUBREG
2199     // that adds a 128 bits reg copy when going through TwoAddressInstructions
2200     // pass. We want to avoid 128 bits copies as much as possible because they
2201     // can't be bundled by our scheduler.
2202     switch(NumVectorElts) {
2203     case 2: RegClassID = R600::R600_Reg64RegClassID; break;
2204     case 4:
2205       if (Opc == AMDGPUISD::BUILD_VERTICAL_VECTOR)
2206         RegClassID = R600::R600_Reg128VerticalRegClassID;
2207       else
2208         RegClassID = R600::R600_Reg128RegClassID;
2209       break;
2210     default: llvm_unreachable("Do not know how to lower this BUILD_VECTOR");
2211     }
2212     SelectBuildVector(N, RegClassID);
2213     return;
2214   }
2215   }
2216 
2217   SelectCode(N);
2218 }
2219 
2220 bool R600DAGToDAGISel::SelectADDRIndirect(SDValue Addr, SDValue &Base,
2221                                           SDValue &Offset) {
2222   ConstantSDNode *C;
2223   SDLoc DL(Addr);
2224 
2225   if ((C = dyn_cast<ConstantSDNode>(Addr))) {
2226     Base = CurDAG->getRegister(R600::INDIRECT_BASE_ADDR, MVT::i32);
2227     Offset = CurDAG->getTargetConstant(C->getZExtValue(), DL, MVT::i32);
2228   } else if ((Addr.getOpcode() == AMDGPUISD::DWORDADDR) &&
2229              (C = dyn_cast<ConstantSDNode>(Addr.getOperand(0)))) {
2230     Base = CurDAG->getRegister(R600::INDIRECT_BASE_ADDR, MVT::i32);
2231     Offset = CurDAG->getTargetConstant(C->getZExtValue(), DL, MVT::i32);
2232   } else if ((Addr.getOpcode() == ISD::ADD || Addr.getOpcode() == ISD::OR) &&
2233             (C = dyn_cast<ConstantSDNode>(Addr.getOperand(1)))) {
2234     Base = Addr.getOperand(0);
2235     Offset = CurDAG->getTargetConstant(C->getZExtValue(), DL, MVT::i32);
2236   } else {
2237     Base = Addr;
2238     Offset = CurDAG->getTargetConstant(0, DL, MVT::i32);
2239   }
2240 
2241   return true;
2242 }
2243 
2244 bool R600DAGToDAGISel::SelectADDRVTX_READ(SDValue Addr, SDValue &Base,
2245                                           SDValue &Offset) {
2246   ConstantSDNode *IMMOffset;
2247 
2248   if (Addr.getOpcode() == ISD::ADD
2249       && (IMMOffset = dyn_cast<ConstantSDNode>(Addr.getOperand(1)))
2250       && isInt<16>(IMMOffset->getZExtValue())) {
2251 
2252       Base = Addr.getOperand(0);
2253       Offset = CurDAG->getTargetConstant(IMMOffset->getZExtValue(), SDLoc(Addr),
2254                                          MVT::i32);
2255       return true;
2256   // If the pointer address is constant, we can move it to the offset field.
2257   } else if ((IMMOffset = dyn_cast<ConstantSDNode>(Addr))
2258              && isInt<16>(IMMOffset->getZExtValue())) {
2259     Base = CurDAG->getCopyFromReg(CurDAG->getEntryNode(),
2260                                   SDLoc(CurDAG->getEntryNode()),
2261                                   R600::ZERO, MVT::i32);
2262     Offset = CurDAG->getTargetConstant(IMMOffset->getZExtValue(), SDLoc(Addr),
2263                                        MVT::i32);
2264     return true;
2265   }
2266 
2267   // Default case, no offset
2268   Base = Addr;
2269   Offset = CurDAG->getTargetConstant(0, SDLoc(Addr), MVT::i32);
2270   return true;
2271 }
2272