1 //===-- SIRegisterInfo.cpp - SI Register Information ---------------------===//
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 /// \file
10 /// SI implementation of the TargetRegisterInfo class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "SIRegisterInfo.h"
15 #include "AMDGPU.h"
16 #include "AMDGPURegisterBankInfo.h"
17 #include "GCNSubtarget.h"
18 #include "MCTargetDesc/AMDGPUInstPrinter.h"
19 #include "MCTargetDesc/AMDGPUMCTargetDesc.h"
20 #include "SIMachineFunctionInfo.h"
21 #include "llvm/CodeGen/LiveIntervals.h"
22 #include "llvm/CodeGen/MachineDominators.h"
23 #include "llvm/CodeGen/RegisterScavenging.h"
24 
25 using namespace llvm;
26 
27 #define GET_REGINFO_TARGET_DESC
28 #include "AMDGPUGenRegisterInfo.inc"
29 
30 static cl::opt<bool> EnableSpillSGPRToVGPR(
31   "amdgpu-spill-sgpr-to-vgpr",
32   cl::desc("Enable spilling VGPRs to SGPRs"),
33   cl::ReallyHidden,
34   cl::init(true));
35 
36 std::array<std::vector<int16_t>, 16> SIRegisterInfo::RegSplitParts;
37 std::array<std::array<uint16_t, 32>, 9> SIRegisterInfo::SubRegFromChannelTable;
38 
39 // Map numbers of DWORDs to indexes in SubRegFromChannelTable.
40 // Valid indexes are shifted 1, such that a 0 mapping means unsupported.
41 // e.g. for 8 DWORDs (256-bit), SubRegFromChannelTableWidthMap[8] = 8,
42 //      meaning index 7 in SubRegFromChannelTable.
43 static const std::array<unsigned, 17> SubRegFromChannelTableWidthMap = {
44     0, 1, 2, 3, 4, 5, 6, 7, 8, 0, 0, 0, 0, 0, 0, 0, 9};
45 
46 namespace llvm {
47 
48 // A temporary struct to spill SGPRs.
49 // This is mostly to spill SGPRs to memory. Spilling SGPRs into VGPR lanes emits
50 // just v_writelane and v_readlane.
51 //
52 // When spilling to memory, the SGPRs are written into VGPR lanes and the VGPR
53 // is saved to scratch (or the other way around for loads).
54 // For this, a VGPR is required where the needed lanes can be clobbered. The
55 // RegScavenger can provide a VGPR where currently active lanes can be
56 // clobbered, but we still need to save inactive lanes.
57 // The high-level steps are:
58 // - Try to scavenge SGPR(s) to save exec
59 // - Try to scavenge VGPR
60 // - Save needed, all or inactive lanes of a TmpVGPR
61 // - Spill/Restore SGPRs using TmpVGPR
62 // - Restore TmpVGPR
63 //
64 // To save all lanes of TmpVGPR, exec needs to be saved and modified. If we
65 // cannot scavenge temporary SGPRs to save exec, we use the following code:
66 // buffer_store_dword TmpVGPR ; only if active lanes need to be saved
67 // s_not exec, exec
68 // buffer_store_dword TmpVGPR ; save inactive lanes
69 // s_not exec, exec
70 struct SGPRSpillBuilder {
71   struct PerVGPRData {
72     unsigned PerVGPR;
73     unsigned NumVGPRs;
74     int64_t VGPRLanes;
75   };
76 
77   // The SGPR to save
78   Register SuperReg;
79   MachineBasicBlock::iterator MI;
80   ArrayRef<int16_t> SplitParts;
81   unsigned NumSubRegs;
82   bool IsKill;
83   const DebugLoc &DL;
84 
85   /* When spilling to stack */
86   // The SGPRs are written into this VGPR, which is then written to scratch
87   // (or vice versa for loads).
88   Register TmpVGPR = AMDGPU::NoRegister;
89   // Temporary spill slot to save TmpVGPR to.
90   int TmpVGPRIndex = 0;
91   // If TmpVGPR is live before the spill or if it is scavenged.
92   bool TmpVGPRLive = false;
93   // Scavenged SGPR to save EXEC.
94   Register SavedExecReg = AMDGPU::NoRegister;
95   // Stack index to write the SGPRs to.
96   int Index;
97   unsigned EltSize = 4;
98 
99   RegScavenger *RS;
100   MachineBasicBlock *MBB;
101   MachineFunction &MF;
102   SIMachineFunctionInfo &MFI;
103   const SIInstrInfo &TII;
104   const SIRegisterInfo &TRI;
105   bool IsWave32;
106   Register ExecReg;
107   unsigned MovOpc;
108   unsigned NotOpc;
109 
110   SGPRSpillBuilder(const SIRegisterInfo &TRI, const SIInstrInfo &TII,
111                    bool IsWave32, MachineBasicBlock::iterator MI, int Index,
112                    RegScavenger *RS)
113       : SGPRSpillBuilder(TRI, TII, IsWave32, MI, MI->getOperand(0).getReg(),
114                          MI->getOperand(0).isKill(), Index, RS) {}
115 
116   SGPRSpillBuilder(const SIRegisterInfo &TRI, const SIInstrInfo &TII,
117                    bool IsWave32, MachineBasicBlock::iterator MI, Register Reg,
118                    bool IsKill, int Index, RegScavenger *RS)
119       : SuperReg(Reg), MI(MI), IsKill(IsKill), DL(MI->getDebugLoc()),
120         Index(Index), RS(RS), MBB(MI->getParent()), MF(*MBB->getParent()),
121         MFI(*MF.getInfo<SIMachineFunctionInfo>()), TII(TII), TRI(TRI),
122         IsWave32(IsWave32) {
123     const TargetRegisterClass *RC = TRI.getPhysRegClass(SuperReg);
124     SplitParts = TRI.getRegSplitParts(RC, EltSize);
125     NumSubRegs = SplitParts.empty() ? 1 : SplitParts.size();
126 
127     if (IsWave32) {
128       ExecReg = AMDGPU::EXEC_LO;
129       MovOpc = AMDGPU::S_MOV_B32;
130       NotOpc = AMDGPU::S_NOT_B32;
131     } else {
132       ExecReg = AMDGPU::EXEC;
133       MovOpc = AMDGPU::S_MOV_B64;
134       NotOpc = AMDGPU::S_NOT_B64;
135     }
136 
137     assert(SuperReg != AMDGPU::M0 && "m0 should never spill");
138     assert(SuperReg != AMDGPU::EXEC_LO && SuperReg != AMDGPU::EXEC_HI &&
139            SuperReg != AMDGPU::EXEC && "exec should never spill");
140   }
141 
142   PerVGPRData getPerVGPRData() {
143     PerVGPRData Data;
144     Data.PerVGPR = IsWave32 ? 32 : 64;
145     Data.NumVGPRs = (NumSubRegs + (Data.PerVGPR - 1)) / Data.PerVGPR;
146     Data.VGPRLanes = (1LL << std::min(Data.PerVGPR, NumSubRegs)) - 1LL;
147     return Data;
148   }
149 
150   // Tries to scavenge SGPRs to save EXEC and a VGPR. Uses v0 if no VGPR is
151   // free.
152   // Writes these instructions if an SGPR can be scavenged:
153   // s_mov_b64 s[6:7], exec   ; Save exec
154   // s_mov_b64 exec, 3        ; Wanted lanemask
155   // buffer_store_dword v1    ; Write scavenged VGPR to emergency slot
156   //
157   // Writes these instructions if no SGPR can be scavenged:
158   // buffer_store_dword v0    ; Only if no free VGPR was found
159   // s_not_b64 exec, exec
160   // buffer_store_dword v0    ; Save inactive lanes
161   //                          ; exec stays inverted, it is flipped back in
162   //                          ; restore.
163   void prepare() {
164     // Scavenged temporary VGPR to use. It must be scavenged once for any number
165     // of spilled subregs.
166     // FIXME: The liveness analysis is limited and does not tell if a register
167     // is in use in lanes that are currently inactive. We can never be sure if
168     // a register as actually in use in another lane, so we need to save all
169     // used lanes of the chosen VGPR.
170     assert(RS && "Cannot spill SGPR to memory without RegScavenger");
171     TmpVGPR = RS->scavengeRegister(&AMDGPU::VGPR_32RegClass, MI, 0, false);
172 
173     // Reserve temporary stack slot
174     TmpVGPRIndex = MFI.getScavengeFI(MF.getFrameInfo(), TRI);
175     if (TmpVGPR) {
176       // Found a register that is dead in the currently active lanes, we only
177       // need to spill inactive lanes.
178       TmpVGPRLive = false;
179     } else {
180       // Pick v0 because it doesn't make a difference.
181       TmpVGPR = AMDGPU::VGPR0;
182       TmpVGPRLive = true;
183     }
184 
185     if (TmpVGPRLive) {
186       // We need to inform the scavenger that this index is already in use until
187       // we're done with the custom emergency spill.
188       RS->assignRegToScavengingIndex(TmpVGPRIndex, TmpVGPR);
189     }
190 
191     // We may end up recursively calling the scavenger, and don't want to re-use
192     // the same register.
193     RS->setRegUsed(TmpVGPR);
194 
195     // Try to scavenge SGPRs to save exec
196     assert(!SavedExecReg && "Exec is already saved, refuse to save again");
197     const TargetRegisterClass &RC =
198         IsWave32 ? AMDGPU::SGPR_32RegClass : AMDGPU::SGPR_64RegClass;
199     RS->setRegUsed(SuperReg);
200     SavedExecReg = RS->scavengeRegister(&RC, MI, 0, false);
201 
202     int64_t VGPRLanes = getPerVGPRData().VGPRLanes;
203 
204     if (SavedExecReg) {
205       RS->setRegUsed(SavedExecReg);
206       // Set exec to needed lanes
207       BuildMI(*MBB, MI, DL, TII.get(MovOpc), SavedExecReg).addReg(ExecReg);
208       auto I =
209           BuildMI(*MBB, MI, DL, TII.get(MovOpc), ExecReg).addImm(VGPRLanes);
210       if (!TmpVGPRLive)
211         I.addReg(TmpVGPR, RegState::ImplicitDefine);
212       // Spill needed lanes
213       TRI.buildVGPRSpillLoadStore(*this, TmpVGPRIndex, 0, /*IsLoad*/ false);
214     } else {
215       // The modify and restore of exec clobber SCC, which we would have to save
216       // and restore. FIXME: We probably would need to reserve a register for
217       // this.
218       if (RS->isRegUsed(AMDGPU::SCC))
219         MI->emitError("unhandled SGPR spill to memory");
220 
221       // Spill active lanes
222       if (TmpVGPRLive)
223         TRI.buildVGPRSpillLoadStore(*this, TmpVGPRIndex, 0, /*IsLoad*/ false,
224                                     /*IsKill*/ false);
225       // Spill inactive lanes
226       auto I = BuildMI(*MBB, MI, DL, TII.get(NotOpc), ExecReg).addReg(ExecReg);
227       if (!TmpVGPRLive)
228         I.addReg(TmpVGPR, RegState::ImplicitDefine);
229       I->getOperand(2).setIsDead(true); // Mark SCC as dead.
230       TRI.buildVGPRSpillLoadStore(*this, TmpVGPRIndex, 0, /*IsLoad*/ false);
231     }
232   }
233 
234   // Writes these instructions if an SGPR can be scavenged:
235   // buffer_load_dword v1     ; Write scavenged VGPR to emergency slot
236   // s_waitcnt vmcnt(0)       ; If a free VGPR was found
237   // s_mov_b64 exec, s[6:7]   ; Save exec
238   //
239   // Writes these instructions if no SGPR can be scavenged:
240   // buffer_load_dword v0     ; Restore inactive lanes
241   // s_waitcnt vmcnt(0)       ; If a free VGPR was found
242   // s_not_b64 exec, exec
243   // buffer_load_dword v0     ; Only if no free VGPR was found
244   void restore() {
245     if (SavedExecReg) {
246       // Restore used lanes
247       TRI.buildVGPRSpillLoadStore(*this, TmpVGPRIndex, 0, /*IsLoad*/ true,
248                                   /*IsKill*/ false);
249       // Restore exec
250       auto I = BuildMI(*MBB, MI, DL, TII.get(MovOpc), ExecReg)
251                    .addReg(SavedExecReg, RegState::Kill);
252       // Add an implicit use of the load so it is not dead.
253       // FIXME This inserts an unnecessary waitcnt
254       if (!TmpVGPRLive) {
255         I.addReg(TmpVGPR, RegState::ImplicitKill);
256       }
257     } else {
258       // Restore inactive lanes
259       TRI.buildVGPRSpillLoadStore(*this, TmpVGPRIndex, 0, /*IsLoad*/ true,
260                                   /*IsKill*/ false);
261       auto I = BuildMI(*MBB, MI, DL, TII.get(NotOpc), ExecReg).addReg(ExecReg);
262       if (!TmpVGPRLive)
263         I.addReg(TmpVGPR, RegState::ImplicitKill);
264       I->getOperand(2).setIsDead(true); // Mark SCC as dead.
265 
266       // Restore active lanes
267       if (TmpVGPRLive)
268         TRI.buildVGPRSpillLoadStore(*this, TmpVGPRIndex, 0, /*IsLoad*/ true);
269     }
270 
271     // Inform the scavenger where we're releasing our custom scavenged register.
272     if (TmpVGPRLive) {
273       MachineBasicBlock::iterator RestorePt = std::prev(MI);
274       RS->assignRegToScavengingIndex(TmpVGPRIndex, TmpVGPR, &*RestorePt);
275     }
276   }
277 
278   // Write TmpVGPR to memory or read TmpVGPR from memory.
279   // Either using a single buffer_load/store if exec is set to the needed mask
280   // or using
281   // buffer_load
282   // s_not exec, exec
283   // buffer_load
284   // s_not exec, exec
285   void readWriteTmpVGPR(unsigned Offset, bool IsLoad) {
286     if (SavedExecReg) {
287       // Spill needed lanes
288       TRI.buildVGPRSpillLoadStore(*this, Index, Offset, IsLoad);
289     } else {
290       // The modify and restore of exec clobber SCC, which we would have to save
291       // and restore. FIXME: We probably would need to reserve a register for
292       // this.
293       if (RS->isRegUsed(AMDGPU::SCC))
294         MI->emitError("unhandled SGPR spill to memory");
295 
296       // Spill active lanes
297       TRI.buildVGPRSpillLoadStore(*this, Index, Offset, IsLoad,
298                                   /*IsKill*/ false);
299       // Spill inactive lanes
300       auto Not0 = BuildMI(*MBB, MI, DL, TII.get(NotOpc), ExecReg).addReg(ExecReg);
301       Not0->getOperand(2).setIsDead(); // Mark SCC as dead.
302       TRI.buildVGPRSpillLoadStore(*this, Index, Offset, IsLoad);
303       auto Not1 = BuildMI(*MBB, MI, DL, TII.get(NotOpc), ExecReg).addReg(ExecReg);
304       Not1->getOperand(2).setIsDead(); // Mark SCC as dead.
305     }
306   }
307 
308   void setMI(MachineBasicBlock *NewMBB, MachineBasicBlock::iterator NewMI) {
309     assert(MBB->getParent() == &MF);
310     MI = NewMI;
311     MBB = NewMBB;
312   }
313 };
314 
315 } // namespace llvm
316 
317 SIRegisterInfo::SIRegisterInfo(const GCNSubtarget &ST)
318     : AMDGPUGenRegisterInfo(AMDGPU::PC_REG, ST.getAMDGPUDwarfFlavour()), ST(ST),
319       SpillSGPRToVGPR(EnableSpillSGPRToVGPR), isWave32(ST.isWave32()) {
320 
321   assert(getSubRegIndexLaneMask(AMDGPU::sub0).getAsInteger() == 3 &&
322          getSubRegIndexLaneMask(AMDGPU::sub31).getAsInteger() == (3ULL << 62) &&
323          (getSubRegIndexLaneMask(AMDGPU::lo16) |
324           getSubRegIndexLaneMask(AMDGPU::hi16)).getAsInteger() ==
325            getSubRegIndexLaneMask(AMDGPU::sub0).getAsInteger() &&
326          "getNumCoveredRegs() will not work with generated subreg masks!");
327 
328   RegPressureIgnoredUnits.resize(getNumRegUnits());
329   RegPressureIgnoredUnits.set(
330       *MCRegUnitIterator(MCRegister::from(AMDGPU::M0), this));
331   for (auto Reg : AMDGPU::VGPR_HI16RegClass)
332     RegPressureIgnoredUnits.set(*MCRegUnitIterator(Reg, this));
333 
334   // HACK: Until this is fully tablegen'd.
335   static llvm::once_flag InitializeRegSplitPartsFlag;
336 
337   static auto InitializeRegSplitPartsOnce = [this]() {
338     for (unsigned Idx = 1, E = getNumSubRegIndices() - 1; Idx < E; ++Idx) {
339       unsigned Size = getSubRegIdxSize(Idx);
340       if (Size & 31)
341         continue;
342       std::vector<int16_t> &Vec = RegSplitParts[Size / 32 - 1];
343       unsigned Pos = getSubRegIdxOffset(Idx);
344       if (Pos % Size)
345         continue;
346       Pos /= Size;
347       if (Vec.empty()) {
348         unsigned MaxNumParts = 1024 / Size; // Maximum register is 1024 bits.
349         Vec.resize(MaxNumParts);
350       }
351       Vec[Pos] = Idx;
352     }
353   };
354 
355   static llvm::once_flag InitializeSubRegFromChannelTableFlag;
356 
357   static auto InitializeSubRegFromChannelTableOnce = [this]() {
358     for (auto &Row : SubRegFromChannelTable)
359       Row.fill(AMDGPU::NoSubRegister);
360     for (uint16_t Idx = 1; Idx < getNumSubRegIndices(); ++Idx) {
361       unsigned Width = AMDGPUSubRegIdxRanges[Idx].Size / 32;
362       unsigned Offset = AMDGPUSubRegIdxRanges[Idx].Offset / 32;
363       assert(Width < SubRegFromChannelTableWidthMap.size());
364       Width = SubRegFromChannelTableWidthMap[Width];
365       if (Width == 0)
366         continue;
367       unsigned TableIdx = Width - 1;
368       assert(TableIdx < SubRegFromChannelTable.size());
369       assert(Offset < SubRegFromChannelTable[TableIdx].size());
370       SubRegFromChannelTable[TableIdx][Offset] = Idx;
371     }
372   };
373 
374   llvm::call_once(InitializeRegSplitPartsFlag, InitializeRegSplitPartsOnce);
375   llvm::call_once(InitializeSubRegFromChannelTableFlag,
376                   InitializeSubRegFromChannelTableOnce);
377 }
378 
379 void SIRegisterInfo::reserveRegisterTuples(BitVector &Reserved,
380                                            MCRegister Reg) const {
381   MCRegAliasIterator R(Reg, this, true);
382 
383   for (; R.isValid(); ++R)
384     Reserved.set(*R);
385 }
386 
387 // Forced to be here by one .inc
388 const MCPhysReg *SIRegisterInfo::getCalleeSavedRegs(
389   const MachineFunction *MF) const {
390   CallingConv::ID CC = MF->getFunction().getCallingConv();
391   switch (CC) {
392   case CallingConv::C:
393   case CallingConv::Fast:
394   case CallingConv::Cold:
395     return ST.hasGFX90AInsts() ? CSR_AMDGPU_HighRegs_With_AGPRs_SaveList
396                                : CSR_AMDGPU_HighRegs_SaveList;
397   case CallingConv::AMDGPU_Gfx:
398     return ST.hasGFX90AInsts() ? CSR_AMDGPU_SI_Gfx_With_AGPRs_SaveList
399                                : CSR_AMDGPU_SI_Gfx_SaveList;
400   default: {
401     // Dummy to not crash RegisterClassInfo.
402     static const MCPhysReg NoCalleeSavedReg = AMDGPU::NoRegister;
403     return &NoCalleeSavedReg;
404   }
405   }
406 }
407 
408 const MCPhysReg *
409 SIRegisterInfo::getCalleeSavedRegsViaCopy(const MachineFunction *MF) const {
410   return nullptr;
411 }
412 
413 const uint32_t *SIRegisterInfo::getCallPreservedMask(const MachineFunction &MF,
414                                                      CallingConv::ID CC) const {
415   switch (CC) {
416   case CallingConv::C:
417   case CallingConv::Fast:
418   case CallingConv::Cold:
419     return ST.hasGFX90AInsts() ? CSR_AMDGPU_HighRegs_With_AGPRs_RegMask
420                                : CSR_AMDGPU_HighRegs_RegMask;
421   case CallingConv::AMDGPU_Gfx:
422     return ST.hasGFX90AInsts() ? CSR_AMDGPU_SI_Gfx_With_AGPRs_RegMask
423                                : CSR_AMDGPU_SI_Gfx_RegMask;
424   default:
425     return nullptr;
426   }
427 }
428 
429 const uint32_t *SIRegisterInfo::getNoPreservedMask() const {
430   return CSR_AMDGPU_NoRegs_RegMask;
431 }
432 
433 const TargetRegisterClass *
434 SIRegisterInfo::getLargestLegalSuperClass(const TargetRegisterClass *RC,
435                                           const MachineFunction &MF) const {
436   // FIXME: Should have a helper function like getEquivalentVGPRClass to get the
437   // equivalent AV class. If used one, the verifier will crash after
438   // RegBankSelect in the GISel flow. The aligned regclasses are not fully given
439   // until Instruction selection.
440   if (ST.hasMAIInsts() && (isVGPRClass(RC) || isAGPRClass(RC))) {
441     if (RC == &AMDGPU::VGPR_32RegClass || RC == &AMDGPU::AGPR_32RegClass)
442       return &AMDGPU::AV_32RegClass;
443     if (RC == &AMDGPU::VReg_64RegClass || RC == &AMDGPU::AReg_64RegClass)
444       return &AMDGPU::AV_64RegClass;
445     if (RC == &AMDGPU::VReg_64_Align2RegClass ||
446         RC == &AMDGPU::AReg_64_Align2RegClass)
447       return &AMDGPU::AV_64_Align2RegClass;
448     if (RC == &AMDGPU::VReg_96RegClass || RC == &AMDGPU::AReg_96RegClass)
449       return &AMDGPU::AV_96RegClass;
450     if (RC == &AMDGPU::VReg_96_Align2RegClass ||
451         RC == &AMDGPU::AReg_96_Align2RegClass)
452       return &AMDGPU::AV_96_Align2RegClass;
453     if (RC == &AMDGPU::VReg_128RegClass || RC == &AMDGPU::AReg_128RegClass)
454       return &AMDGPU::AV_128RegClass;
455     if (RC == &AMDGPU::VReg_128_Align2RegClass ||
456         RC == &AMDGPU::AReg_128_Align2RegClass)
457       return &AMDGPU::AV_128_Align2RegClass;
458     if (RC == &AMDGPU::VReg_160RegClass || RC == &AMDGPU::AReg_160RegClass)
459       return &AMDGPU::AV_160RegClass;
460     if (RC == &AMDGPU::VReg_160_Align2RegClass ||
461         RC == &AMDGPU::AReg_160_Align2RegClass)
462       return &AMDGPU::AV_160_Align2RegClass;
463     if (RC == &AMDGPU::VReg_192RegClass || RC == &AMDGPU::AReg_192RegClass)
464       return &AMDGPU::AV_192RegClass;
465     if (RC == &AMDGPU::VReg_192_Align2RegClass ||
466         RC == &AMDGPU::AReg_192_Align2RegClass)
467       return &AMDGPU::AV_192_Align2RegClass;
468     if (RC == &AMDGPU::VReg_256RegClass || RC == &AMDGPU::AReg_256RegClass)
469       return &AMDGPU::AV_256RegClass;
470     if (RC == &AMDGPU::VReg_256_Align2RegClass ||
471         RC == &AMDGPU::AReg_256_Align2RegClass)
472       return &AMDGPU::AV_256_Align2RegClass;
473     if (RC == &AMDGPU::VReg_512RegClass || RC == &AMDGPU::AReg_512RegClass)
474       return &AMDGPU::AV_512RegClass;
475     if (RC == &AMDGPU::VReg_512_Align2RegClass ||
476         RC == &AMDGPU::AReg_512_Align2RegClass)
477       return &AMDGPU::AV_512_Align2RegClass;
478     if (RC == &AMDGPU::VReg_1024RegClass || RC == &AMDGPU::AReg_1024RegClass)
479       return &AMDGPU::AV_1024RegClass;
480     if (RC == &AMDGPU::VReg_1024_Align2RegClass ||
481         RC == &AMDGPU::AReg_1024_Align2RegClass)
482       return &AMDGPU::AV_1024_Align2RegClass;
483   }
484 
485   return TargetRegisterInfo::getLargestLegalSuperClass(RC, MF);
486 }
487 
488 Register SIRegisterInfo::getFrameRegister(const MachineFunction &MF) const {
489   const SIFrameLowering *TFI = ST.getFrameLowering();
490   const SIMachineFunctionInfo *FuncInfo = MF.getInfo<SIMachineFunctionInfo>();
491   // During ISel lowering we always reserve the stack pointer in entry
492   // functions, but never actually want to reference it when accessing our own
493   // frame. If we need a frame pointer we use it, but otherwise we can just use
494   // an immediate "0" which we represent by returning NoRegister.
495   if (FuncInfo->isEntryFunction()) {
496     return TFI->hasFP(MF) ? FuncInfo->getFrameOffsetReg() : Register();
497   }
498   return TFI->hasFP(MF) ? FuncInfo->getFrameOffsetReg()
499                         : FuncInfo->getStackPtrOffsetReg();
500 }
501 
502 bool SIRegisterInfo::hasBasePointer(const MachineFunction &MF) const {
503   // When we need stack realignment, we can't reference off of the
504   // stack pointer, so we reserve a base pointer.
505   const MachineFrameInfo &MFI = MF.getFrameInfo();
506   return MFI.getNumFixedObjects() && shouldRealignStack(MF);
507 }
508 
509 Register SIRegisterInfo::getBaseRegister() const { return AMDGPU::SGPR34; }
510 
511 const uint32_t *SIRegisterInfo::getAllVGPRRegMask() const {
512   return CSR_AMDGPU_AllVGPRs_RegMask;
513 }
514 
515 const uint32_t *SIRegisterInfo::getAllAGPRRegMask() const {
516   return CSR_AMDGPU_AllAGPRs_RegMask;
517 }
518 
519 const uint32_t *SIRegisterInfo::getAllVectorRegMask() const {
520   return CSR_AMDGPU_AllVectorRegs_RegMask;
521 }
522 
523 const uint32_t *SIRegisterInfo::getAllAllocatableSRegMask() const {
524   return CSR_AMDGPU_AllAllocatableSRegs_RegMask;
525 }
526 
527 unsigned SIRegisterInfo::getSubRegFromChannel(unsigned Channel,
528                                               unsigned NumRegs) {
529   assert(NumRegs < SubRegFromChannelTableWidthMap.size());
530   unsigned NumRegIndex = SubRegFromChannelTableWidthMap[NumRegs];
531   assert(NumRegIndex && "Not implemented");
532   assert(Channel < SubRegFromChannelTable[NumRegIndex - 1].size());
533   return SubRegFromChannelTable[NumRegIndex - 1][Channel];
534 }
535 
536 MCRegister SIRegisterInfo::reservedPrivateSegmentBufferReg(
537   const MachineFunction &MF) const {
538   unsigned BaseIdx = alignDown(ST.getMaxNumSGPRs(MF), 4) - 4;
539   MCRegister BaseReg(AMDGPU::SGPR_32RegClass.getRegister(BaseIdx));
540   return getMatchingSuperReg(BaseReg, AMDGPU::sub0, &AMDGPU::SGPR_128RegClass);
541 }
542 
543 BitVector SIRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
544   BitVector Reserved(getNumRegs());
545   Reserved.set(AMDGPU::MODE);
546 
547   // EXEC_LO and EXEC_HI could be allocated and used as regular register, but
548   // this seems likely to result in bugs, so I'm marking them as reserved.
549   reserveRegisterTuples(Reserved, AMDGPU::EXEC);
550   reserveRegisterTuples(Reserved, AMDGPU::FLAT_SCR);
551 
552   // M0 has to be reserved so that llvm accepts it as a live-in into a block.
553   reserveRegisterTuples(Reserved, AMDGPU::M0);
554 
555   // Reserve src_vccz, src_execz, src_scc.
556   reserveRegisterTuples(Reserved, AMDGPU::SRC_VCCZ);
557   reserveRegisterTuples(Reserved, AMDGPU::SRC_EXECZ);
558   reserveRegisterTuples(Reserved, AMDGPU::SRC_SCC);
559 
560   // Reserve the memory aperture registers.
561   reserveRegisterTuples(Reserved, AMDGPU::SRC_SHARED_BASE);
562   reserveRegisterTuples(Reserved, AMDGPU::SRC_SHARED_LIMIT);
563   reserveRegisterTuples(Reserved, AMDGPU::SRC_PRIVATE_BASE);
564   reserveRegisterTuples(Reserved, AMDGPU::SRC_PRIVATE_LIMIT);
565 
566   // Reserve src_pops_exiting_wave_id - support is not implemented in Codegen.
567   reserveRegisterTuples(Reserved, AMDGPU::SRC_POPS_EXITING_WAVE_ID);
568 
569   // Reserve xnack_mask registers - support is not implemented in Codegen.
570   reserveRegisterTuples(Reserved, AMDGPU::XNACK_MASK);
571 
572   // Reserve lds_direct register - support is not implemented in Codegen.
573   reserveRegisterTuples(Reserved, AMDGPU::LDS_DIRECT);
574 
575   // Reserve Trap Handler registers - support is not implemented in Codegen.
576   reserveRegisterTuples(Reserved, AMDGPU::TBA);
577   reserveRegisterTuples(Reserved, AMDGPU::TMA);
578   reserveRegisterTuples(Reserved, AMDGPU::TTMP0_TTMP1);
579   reserveRegisterTuples(Reserved, AMDGPU::TTMP2_TTMP3);
580   reserveRegisterTuples(Reserved, AMDGPU::TTMP4_TTMP5);
581   reserveRegisterTuples(Reserved, AMDGPU::TTMP6_TTMP7);
582   reserveRegisterTuples(Reserved, AMDGPU::TTMP8_TTMP9);
583   reserveRegisterTuples(Reserved, AMDGPU::TTMP10_TTMP11);
584   reserveRegisterTuples(Reserved, AMDGPU::TTMP12_TTMP13);
585   reserveRegisterTuples(Reserved, AMDGPU::TTMP14_TTMP15);
586 
587   // Reserve null register - it shall never be allocated
588   reserveRegisterTuples(Reserved, AMDGPU::SGPR_NULL);
589 
590   // Disallow vcc_hi allocation in wave32. It may be allocated but most likely
591   // will result in bugs.
592   if (isWave32) {
593     Reserved.set(AMDGPU::VCC);
594     Reserved.set(AMDGPU::VCC_HI);
595   }
596 
597   unsigned MaxNumSGPRs = ST.getMaxNumSGPRs(MF);
598   unsigned TotalNumSGPRs = AMDGPU::SGPR_32RegClass.getNumRegs();
599   for (unsigned i = MaxNumSGPRs; i < TotalNumSGPRs; ++i) {
600     unsigned Reg = AMDGPU::SGPR_32RegClass.getRegister(i);
601     reserveRegisterTuples(Reserved, Reg);
602   }
603 
604   const SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
605   unsigned MaxNumVGPRs = ST.getMaxNumVGPRs(MF);
606   unsigned MaxNumAGPRs = MaxNumVGPRs;
607   unsigned TotalNumVGPRs = AMDGPU::VGPR_32RegClass.getNumRegs();
608 
609   if (ST.hasGFX90AInsts()) {
610     // In an entry function without calls and AGPRs used it is possible to use
611     // the whole register budget for VGPRs.
612 
613     // TODO: it shall be possible to estimate maximum AGPR/VGPR pressure and
614     //       split register file accordingly.
615     if (MFI->usesAGPRs(MF)) {
616       MaxNumVGPRs /= 2;
617       MaxNumAGPRs = MaxNumVGPRs;
618     } else {
619       if (MaxNumVGPRs > TotalNumVGPRs) {
620         MaxNumAGPRs = MaxNumVGPRs - TotalNumVGPRs;
621         MaxNumVGPRs = TotalNumVGPRs;
622       } else
623         MaxNumAGPRs = 0;
624     }
625   } else if (ST.hasMAIInsts() && MFI->usesAGPRs(MF)) {
626     // In order to guarantee copying between AGPRs, we need a scratch VGPR
627     // available at all times.
628     reserveRegisterTuples(Reserved, AMDGPU::VGPR32);
629   }
630 
631   for (unsigned i = MaxNumVGPRs; i < TotalNumVGPRs; ++i) {
632     unsigned Reg = AMDGPU::VGPR_32RegClass.getRegister(i);
633     reserveRegisterTuples(Reserved, Reg);
634   }
635 
636   for (unsigned i = MaxNumAGPRs; i < TotalNumVGPRs; ++i) {
637     unsigned Reg = AMDGPU::AGPR_32RegClass.getRegister(i);
638     reserveRegisterTuples(Reserved, Reg);
639   }
640 
641   for (auto Reg : AMDGPU::SReg_32RegClass) {
642     Reserved.set(getSubReg(Reg, AMDGPU::hi16));
643     Register Low = getSubReg(Reg, AMDGPU::lo16);
644     // This is to prevent BB vcc liveness errors.
645     if (!AMDGPU::SGPR_LO16RegClass.contains(Low))
646       Reserved.set(Low);
647   }
648 
649   for (auto Reg : AMDGPU::AGPR_32RegClass) {
650     Reserved.set(getSubReg(Reg, AMDGPU::hi16));
651   }
652 
653   // Reserve all the rest AGPRs if there are no instructions to use it.
654   if (!ST.hasMAIInsts()) {
655     for (unsigned i = 0; i < MaxNumVGPRs; ++i) {
656       unsigned Reg = AMDGPU::AGPR_32RegClass.getRegister(i);
657       reserveRegisterTuples(Reserved, Reg);
658     }
659   }
660 
661   Register ScratchRSrcReg = MFI->getScratchRSrcReg();
662   if (ScratchRSrcReg != AMDGPU::NoRegister) {
663     // Reserve 4 SGPRs for the scratch buffer resource descriptor in case we need
664     // to spill.
665     // TODO: May need to reserve a VGPR if doing LDS spilling.
666     reserveRegisterTuples(Reserved, ScratchRSrcReg);
667   }
668 
669   // We have to assume the SP is needed in case there are calls in the function,
670   // which is detected after the function is lowered. If we aren't really going
671   // to need SP, don't bother reserving it.
672   MCRegister StackPtrReg = MFI->getStackPtrOffsetReg();
673 
674   if (StackPtrReg) {
675     reserveRegisterTuples(Reserved, StackPtrReg);
676     assert(!isSubRegister(ScratchRSrcReg, StackPtrReg));
677   }
678 
679   MCRegister FrameReg = MFI->getFrameOffsetReg();
680   if (FrameReg) {
681     reserveRegisterTuples(Reserved, FrameReg);
682     assert(!isSubRegister(ScratchRSrcReg, FrameReg));
683   }
684 
685   if (hasBasePointer(MF)) {
686     MCRegister BasePtrReg = getBaseRegister();
687     reserveRegisterTuples(Reserved, BasePtrReg);
688     assert(!isSubRegister(ScratchRSrcReg, BasePtrReg));
689   }
690 
691   for (auto Reg : MFI->WWMReservedRegs) {
692     reserveRegisterTuples(Reserved, Reg.first);
693   }
694 
695   // Reserve VGPRs used for SGPR spilling.
696   // Note we treat freezeReservedRegs unusually because we run register
697   // allocation in two phases. It's OK to re-freeze with new registers for the
698   // second run.
699 #if 0
700   for (auto &SpilledFI : MFI->sgpr_spill_vgprs()) {
701     for (auto &SpilledVGPR : SpilledFI.second)
702       reserveRegisterTuples(Reserved, SpilledVGPR.VGPR);
703   }
704 #endif
705 
706   // FIXME: Stop using reserved registers for this.
707   for (MCPhysReg Reg : MFI->getAGPRSpillVGPRs())
708     reserveRegisterTuples(Reserved, Reg);
709 
710   for (MCPhysReg Reg : MFI->getVGPRSpillAGPRs())
711     reserveRegisterTuples(Reserved, Reg);
712 
713   for (auto SSpill : MFI->getSGPRSpillVGPRs())
714     reserveRegisterTuples(Reserved, SSpill.VGPR);
715 
716   return Reserved;
717 }
718 
719 bool SIRegisterInfo::isAsmClobberable(const MachineFunction &MF,
720                                       MCRegister PhysReg) const {
721   return !MF.getRegInfo().isReserved(PhysReg);
722 }
723 
724 bool SIRegisterInfo::shouldRealignStack(const MachineFunction &MF) const {
725   const SIMachineFunctionInfo *Info = MF.getInfo<SIMachineFunctionInfo>();
726   // On entry, the base address is 0, so it can't possibly need any more
727   // alignment.
728 
729   // FIXME: Should be able to specify the entry frame alignment per calling
730   // convention instead.
731   if (Info->isEntryFunction())
732     return false;
733 
734   return TargetRegisterInfo::shouldRealignStack(MF);
735 }
736 
737 bool SIRegisterInfo::requiresRegisterScavenging(const MachineFunction &Fn) const {
738   const SIMachineFunctionInfo *Info = Fn.getInfo<SIMachineFunctionInfo>();
739   if (Info->isEntryFunction()) {
740     const MachineFrameInfo &MFI = Fn.getFrameInfo();
741     return MFI.hasStackObjects() || MFI.hasCalls();
742   }
743 
744   // May need scavenger for dealing with callee saved registers.
745   return true;
746 }
747 
748 bool SIRegisterInfo::requiresFrameIndexScavenging(
749   const MachineFunction &MF) const {
750   // Do not use frame virtual registers. They used to be used for SGPRs, but
751   // once we reach PrologEpilogInserter, we can no longer spill SGPRs. If the
752   // scavenger fails, we can increment/decrement the necessary SGPRs to avoid a
753   // spill.
754   return false;
755 }
756 
757 bool SIRegisterInfo::requiresFrameIndexReplacementScavenging(
758   const MachineFunction &MF) const {
759   const MachineFrameInfo &MFI = MF.getFrameInfo();
760   return MFI.hasStackObjects();
761 }
762 
763 bool SIRegisterInfo::requiresVirtualBaseRegisters(
764   const MachineFunction &) const {
765   // There are no special dedicated stack or frame pointers.
766   return true;
767 }
768 
769 int64_t SIRegisterInfo::getScratchInstrOffset(const MachineInstr *MI) const {
770   assert(SIInstrInfo::isMUBUF(*MI) || SIInstrInfo::isFLATScratch(*MI));
771 
772   int OffIdx = AMDGPU::getNamedOperandIdx(MI->getOpcode(),
773                                           AMDGPU::OpName::offset);
774   return MI->getOperand(OffIdx).getImm();
775 }
776 
777 int64_t SIRegisterInfo::getFrameIndexInstrOffset(const MachineInstr *MI,
778                                                  int Idx) const {
779   if (!SIInstrInfo::isMUBUF(*MI) && !SIInstrInfo::isFLATScratch(*MI))
780     return 0;
781 
782   assert((Idx == AMDGPU::getNamedOperandIdx(MI->getOpcode(),
783                                             AMDGPU::OpName::vaddr) ||
784          (Idx == AMDGPU::getNamedOperandIdx(MI->getOpcode(),
785                                             AMDGPU::OpName::saddr))) &&
786          "Should never see frame index on non-address operand");
787 
788   return getScratchInstrOffset(MI);
789 }
790 
791 bool SIRegisterInfo::needsFrameBaseReg(MachineInstr *MI, int64_t Offset) const {
792   if (!SIInstrInfo::isMUBUF(*MI) && !SIInstrInfo::isFLATScratch(*MI))
793     return false;
794 
795   int64_t FullOffset = Offset + getScratchInstrOffset(MI);
796 
797   if (SIInstrInfo::isMUBUF(*MI))
798     return !SIInstrInfo::isLegalMUBUFImmOffset(FullOffset);
799 
800   const SIInstrInfo *TII = ST.getInstrInfo();
801   return !TII->isLegalFLATOffset(FullOffset, AMDGPUAS::PRIVATE_ADDRESS,
802                                  SIInstrFlags::FlatScratch);
803 }
804 
805 Register SIRegisterInfo::materializeFrameBaseRegister(MachineBasicBlock *MBB,
806                                                       int FrameIdx,
807                                                       int64_t Offset) const {
808   MachineBasicBlock::iterator Ins = MBB->begin();
809   DebugLoc DL; // Defaults to "unknown"
810 
811   if (Ins != MBB->end())
812     DL = Ins->getDebugLoc();
813 
814   MachineFunction *MF = MBB->getParent();
815   const SIInstrInfo *TII = ST.getInstrInfo();
816   MachineRegisterInfo &MRI = MF->getRegInfo();
817   unsigned MovOpc = ST.enableFlatScratch() ? AMDGPU::S_MOV_B32
818                                            : AMDGPU::V_MOV_B32_e32;
819 
820   Register BaseReg = MRI.createVirtualRegister(
821       ST.enableFlatScratch() ? &AMDGPU::SReg_32_XEXEC_HIRegClass
822                              : &AMDGPU::VGPR_32RegClass);
823 
824   if (Offset == 0) {
825     BuildMI(*MBB, Ins, DL, TII->get(MovOpc), BaseReg)
826       .addFrameIndex(FrameIdx);
827     return BaseReg;
828   }
829 
830   Register OffsetReg = MRI.createVirtualRegister(&AMDGPU::SReg_32_XM0RegClass);
831 
832   Register FIReg = MRI.createVirtualRegister(
833       ST.enableFlatScratch() ? &AMDGPU::SReg_32_XM0RegClass
834                              : &AMDGPU::VGPR_32RegClass);
835 
836   BuildMI(*MBB, Ins, DL, TII->get(AMDGPU::S_MOV_B32), OffsetReg)
837     .addImm(Offset);
838   BuildMI(*MBB, Ins, DL, TII->get(MovOpc), FIReg)
839     .addFrameIndex(FrameIdx);
840 
841   if (ST.enableFlatScratch() ) {
842     BuildMI(*MBB, Ins, DL, TII->get(AMDGPU::S_ADD_I32), BaseReg)
843         .addReg(OffsetReg, RegState::Kill)
844         .addReg(FIReg);
845     return BaseReg;
846   }
847 
848   TII->getAddNoCarry(*MBB, Ins, DL, BaseReg)
849     .addReg(OffsetReg, RegState::Kill)
850     .addReg(FIReg)
851     .addImm(0); // clamp bit
852 
853   return BaseReg;
854 }
855 
856 void SIRegisterInfo::resolveFrameIndex(MachineInstr &MI, Register BaseReg,
857                                        int64_t Offset) const {
858   const SIInstrInfo *TII = ST.getInstrInfo();
859   bool IsFlat = TII->isFLATScratch(MI);
860 
861 #ifndef NDEBUG
862   // FIXME: Is it possible to be storing a frame index to itself?
863   bool SeenFI = false;
864   for (const MachineOperand &MO: MI.operands()) {
865     if (MO.isFI()) {
866       if (SeenFI)
867         llvm_unreachable("should not see multiple frame indices");
868 
869       SeenFI = true;
870     }
871   }
872 #endif
873 
874   MachineOperand *FIOp =
875       TII->getNamedOperand(MI, IsFlat ? AMDGPU::OpName::saddr
876                                       : AMDGPU::OpName::vaddr);
877 
878   MachineOperand *OffsetOp = TII->getNamedOperand(MI, AMDGPU::OpName::offset);
879   int64_t NewOffset = OffsetOp->getImm() + Offset;
880 
881   assert(FIOp && FIOp->isFI() && "frame index must be address operand");
882   assert(TII->isMUBUF(MI) || TII->isFLATScratch(MI));
883 
884   if (IsFlat) {
885     assert(TII->isLegalFLATOffset(NewOffset, AMDGPUAS::PRIVATE_ADDRESS,
886                                   SIInstrFlags::FlatScratch) &&
887            "offset should be legal");
888     FIOp->ChangeToRegister(BaseReg, false);
889     OffsetOp->setImm(NewOffset);
890     return;
891   }
892 
893 #ifndef NDEBUG
894   MachineOperand *SOffset = TII->getNamedOperand(MI, AMDGPU::OpName::soffset);
895   assert(SOffset->isImm() && SOffset->getImm() == 0);
896 #endif
897 
898   assert(SIInstrInfo::isLegalMUBUFImmOffset(NewOffset) &&
899          "offset should be legal");
900 
901   FIOp->ChangeToRegister(BaseReg, false);
902   OffsetOp->setImm(NewOffset);
903 }
904 
905 bool SIRegisterInfo::isFrameOffsetLegal(const MachineInstr *MI,
906                                         Register BaseReg,
907                                         int64_t Offset) const {
908   if (!SIInstrInfo::isMUBUF(*MI) && !SIInstrInfo::isFLATScratch(*MI))
909     return false;
910 
911   int64_t NewOffset = Offset + getScratchInstrOffset(MI);
912 
913   if (SIInstrInfo::isMUBUF(*MI))
914     return SIInstrInfo::isLegalMUBUFImmOffset(NewOffset);
915 
916   const SIInstrInfo *TII = ST.getInstrInfo();
917   return TII->isLegalFLATOffset(NewOffset, AMDGPUAS::PRIVATE_ADDRESS,
918                                 SIInstrFlags::FlatScratch);
919 }
920 
921 const TargetRegisterClass *SIRegisterInfo::getPointerRegClass(
922   const MachineFunction &MF, unsigned Kind) const {
923   // This is inaccurate. It depends on the instruction and address space. The
924   // only place where we should hit this is for dealing with frame indexes /
925   // private accesses, so this is correct in that case.
926   return &AMDGPU::VGPR_32RegClass;
927 }
928 
929 const TargetRegisterClass *
930 SIRegisterInfo::getCrossCopyRegClass(const TargetRegisterClass *RC) const {
931   if (isAGPRClass(RC) && !ST.hasGFX90AInsts())
932     return getEquivalentVGPRClass(RC);
933 
934   return RC;
935 }
936 
937 static unsigned getNumSubRegsForSpillOp(unsigned Op) {
938 
939   switch (Op) {
940   case AMDGPU::SI_SPILL_S1024_SAVE:
941   case AMDGPU::SI_SPILL_S1024_RESTORE:
942   case AMDGPU::SI_SPILL_V1024_SAVE:
943   case AMDGPU::SI_SPILL_V1024_RESTORE:
944   case AMDGPU::SI_SPILL_A1024_SAVE:
945   case AMDGPU::SI_SPILL_A1024_RESTORE:
946   case AMDGPU::SI_SPILL_AV1024_SAVE:
947   case AMDGPU::SI_SPILL_AV1024_RESTORE:
948     return 32;
949   case AMDGPU::SI_SPILL_S512_SAVE:
950   case AMDGPU::SI_SPILL_S512_RESTORE:
951   case AMDGPU::SI_SPILL_V512_SAVE:
952   case AMDGPU::SI_SPILL_V512_RESTORE:
953   case AMDGPU::SI_SPILL_A512_SAVE:
954   case AMDGPU::SI_SPILL_A512_RESTORE:
955   case AMDGPU::SI_SPILL_AV512_SAVE:
956   case AMDGPU::SI_SPILL_AV512_RESTORE:
957     return 16;
958   case AMDGPU::SI_SPILL_S256_SAVE:
959   case AMDGPU::SI_SPILL_S256_RESTORE:
960   case AMDGPU::SI_SPILL_V256_SAVE:
961   case AMDGPU::SI_SPILL_V256_RESTORE:
962   case AMDGPU::SI_SPILL_A256_SAVE:
963   case AMDGPU::SI_SPILL_A256_RESTORE:
964   case AMDGPU::SI_SPILL_AV256_SAVE:
965   case AMDGPU::SI_SPILL_AV256_RESTORE:
966     return 8;
967   case AMDGPU::SI_SPILL_S224_SAVE:
968   case AMDGPU::SI_SPILL_S224_RESTORE:
969   case AMDGPU::SI_SPILL_V224_SAVE:
970   case AMDGPU::SI_SPILL_V224_RESTORE:
971   case AMDGPU::SI_SPILL_A224_SAVE:
972   case AMDGPU::SI_SPILL_A224_RESTORE:
973   case AMDGPU::SI_SPILL_AV224_SAVE:
974   case AMDGPU::SI_SPILL_AV224_RESTORE:
975     return 7;
976   case AMDGPU::SI_SPILL_S192_SAVE:
977   case AMDGPU::SI_SPILL_S192_RESTORE:
978   case AMDGPU::SI_SPILL_V192_SAVE:
979   case AMDGPU::SI_SPILL_V192_RESTORE:
980   case AMDGPU::SI_SPILL_A192_SAVE:
981   case AMDGPU::SI_SPILL_A192_RESTORE:
982   case AMDGPU::SI_SPILL_AV192_SAVE:
983   case AMDGPU::SI_SPILL_AV192_RESTORE:
984     return 6;
985   case AMDGPU::SI_SPILL_S160_SAVE:
986   case AMDGPU::SI_SPILL_S160_RESTORE:
987   case AMDGPU::SI_SPILL_V160_SAVE:
988   case AMDGPU::SI_SPILL_V160_RESTORE:
989   case AMDGPU::SI_SPILL_A160_SAVE:
990   case AMDGPU::SI_SPILL_A160_RESTORE:
991   case AMDGPU::SI_SPILL_AV160_SAVE:
992   case AMDGPU::SI_SPILL_AV160_RESTORE:
993     return 5;
994   case AMDGPU::SI_SPILL_S128_SAVE:
995   case AMDGPU::SI_SPILL_S128_RESTORE:
996   case AMDGPU::SI_SPILL_V128_SAVE:
997   case AMDGPU::SI_SPILL_V128_RESTORE:
998   case AMDGPU::SI_SPILL_A128_SAVE:
999   case AMDGPU::SI_SPILL_A128_RESTORE:
1000   case AMDGPU::SI_SPILL_AV128_SAVE:
1001   case AMDGPU::SI_SPILL_AV128_RESTORE:
1002     return 4;
1003   case AMDGPU::SI_SPILL_S96_SAVE:
1004   case AMDGPU::SI_SPILL_S96_RESTORE:
1005   case AMDGPU::SI_SPILL_V96_SAVE:
1006   case AMDGPU::SI_SPILL_V96_RESTORE:
1007   case AMDGPU::SI_SPILL_A96_SAVE:
1008   case AMDGPU::SI_SPILL_A96_RESTORE:
1009   case AMDGPU::SI_SPILL_AV96_SAVE:
1010   case AMDGPU::SI_SPILL_AV96_RESTORE:
1011     return 3;
1012   case AMDGPU::SI_SPILL_S64_SAVE:
1013   case AMDGPU::SI_SPILL_S64_RESTORE:
1014   case AMDGPU::SI_SPILL_V64_SAVE:
1015   case AMDGPU::SI_SPILL_V64_RESTORE:
1016   case AMDGPU::SI_SPILL_A64_SAVE:
1017   case AMDGPU::SI_SPILL_A64_RESTORE:
1018   case AMDGPU::SI_SPILL_AV64_SAVE:
1019   case AMDGPU::SI_SPILL_AV64_RESTORE:
1020     return 2;
1021   case AMDGPU::SI_SPILL_S32_SAVE:
1022   case AMDGPU::SI_SPILL_S32_RESTORE:
1023   case AMDGPU::SI_SPILL_V32_SAVE:
1024   case AMDGPU::SI_SPILL_V32_RESTORE:
1025   case AMDGPU::SI_SPILL_A32_SAVE:
1026   case AMDGPU::SI_SPILL_A32_RESTORE:
1027   case AMDGPU::SI_SPILL_AV32_SAVE:
1028   case AMDGPU::SI_SPILL_AV32_RESTORE:
1029     return 1;
1030   default: llvm_unreachable("Invalid spill opcode");
1031   }
1032 }
1033 
1034 static int getOffsetMUBUFStore(unsigned Opc) {
1035   switch (Opc) {
1036   case AMDGPU::BUFFER_STORE_DWORD_OFFEN:
1037     return AMDGPU::BUFFER_STORE_DWORD_OFFSET;
1038   case AMDGPU::BUFFER_STORE_BYTE_OFFEN:
1039     return AMDGPU::BUFFER_STORE_BYTE_OFFSET;
1040   case AMDGPU::BUFFER_STORE_SHORT_OFFEN:
1041     return AMDGPU::BUFFER_STORE_SHORT_OFFSET;
1042   case AMDGPU::BUFFER_STORE_DWORDX2_OFFEN:
1043     return AMDGPU::BUFFER_STORE_DWORDX2_OFFSET;
1044   case AMDGPU::BUFFER_STORE_DWORDX3_OFFEN:
1045     return AMDGPU::BUFFER_STORE_DWORDX3_OFFSET;
1046   case AMDGPU::BUFFER_STORE_DWORDX4_OFFEN:
1047     return AMDGPU::BUFFER_STORE_DWORDX4_OFFSET;
1048   case AMDGPU::BUFFER_STORE_SHORT_D16_HI_OFFEN:
1049     return AMDGPU::BUFFER_STORE_SHORT_D16_HI_OFFSET;
1050   case AMDGPU::BUFFER_STORE_BYTE_D16_HI_OFFEN:
1051     return AMDGPU::BUFFER_STORE_BYTE_D16_HI_OFFSET;
1052   default:
1053     return -1;
1054   }
1055 }
1056 
1057 static int getOffsetMUBUFLoad(unsigned Opc) {
1058   switch (Opc) {
1059   case AMDGPU::BUFFER_LOAD_DWORD_OFFEN:
1060     return AMDGPU::BUFFER_LOAD_DWORD_OFFSET;
1061   case AMDGPU::BUFFER_LOAD_UBYTE_OFFEN:
1062     return AMDGPU::BUFFER_LOAD_UBYTE_OFFSET;
1063   case AMDGPU::BUFFER_LOAD_SBYTE_OFFEN:
1064     return AMDGPU::BUFFER_LOAD_SBYTE_OFFSET;
1065   case AMDGPU::BUFFER_LOAD_USHORT_OFFEN:
1066     return AMDGPU::BUFFER_LOAD_USHORT_OFFSET;
1067   case AMDGPU::BUFFER_LOAD_SSHORT_OFFEN:
1068     return AMDGPU::BUFFER_LOAD_SSHORT_OFFSET;
1069   case AMDGPU::BUFFER_LOAD_DWORDX2_OFFEN:
1070     return AMDGPU::BUFFER_LOAD_DWORDX2_OFFSET;
1071   case AMDGPU::BUFFER_LOAD_DWORDX3_OFFEN:
1072     return AMDGPU::BUFFER_LOAD_DWORDX3_OFFSET;
1073   case AMDGPU::BUFFER_LOAD_DWORDX4_OFFEN:
1074     return AMDGPU::BUFFER_LOAD_DWORDX4_OFFSET;
1075   case AMDGPU::BUFFER_LOAD_UBYTE_D16_OFFEN:
1076     return AMDGPU::BUFFER_LOAD_UBYTE_D16_OFFSET;
1077   case AMDGPU::BUFFER_LOAD_UBYTE_D16_HI_OFFEN:
1078     return AMDGPU::BUFFER_LOAD_UBYTE_D16_HI_OFFSET;
1079   case AMDGPU::BUFFER_LOAD_SBYTE_D16_OFFEN:
1080     return AMDGPU::BUFFER_LOAD_SBYTE_D16_OFFSET;
1081   case AMDGPU::BUFFER_LOAD_SBYTE_D16_HI_OFFEN:
1082     return AMDGPU::BUFFER_LOAD_SBYTE_D16_HI_OFFSET;
1083   case AMDGPU::BUFFER_LOAD_SHORT_D16_OFFEN:
1084     return AMDGPU::BUFFER_LOAD_SHORT_D16_OFFSET;
1085   case AMDGPU::BUFFER_LOAD_SHORT_D16_HI_OFFEN:
1086     return AMDGPU::BUFFER_LOAD_SHORT_D16_HI_OFFSET;
1087   default:
1088     return -1;
1089   }
1090 }
1091 
1092 static int getOffenMUBUFStore(unsigned Opc) {
1093   switch (Opc) {
1094   case AMDGPU::BUFFER_STORE_DWORD_OFFSET:
1095     return AMDGPU::BUFFER_STORE_DWORD_OFFEN;
1096   case AMDGPU::BUFFER_STORE_BYTE_OFFSET:
1097     return AMDGPU::BUFFER_STORE_BYTE_OFFEN;
1098   case AMDGPU::BUFFER_STORE_SHORT_OFFSET:
1099     return AMDGPU::BUFFER_STORE_SHORT_OFFEN;
1100   case AMDGPU::BUFFER_STORE_DWORDX2_OFFSET:
1101     return AMDGPU::BUFFER_STORE_DWORDX2_OFFEN;
1102   case AMDGPU::BUFFER_STORE_DWORDX3_OFFSET:
1103     return AMDGPU::BUFFER_STORE_DWORDX3_OFFEN;
1104   case AMDGPU::BUFFER_STORE_DWORDX4_OFFSET:
1105     return AMDGPU::BUFFER_STORE_DWORDX4_OFFEN;
1106   case AMDGPU::BUFFER_STORE_SHORT_D16_HI_OFFSET:
1107     return AMDGPU::BUFFER_STORE_SHORT_D16_HI_OFFEN;
1108   case AMDGPU::BUFFER_STORE_BYTE_D16_HI_OFFSET:
1109     return AMDGPU::BUFFER_STORE_BYTE_D16_HI_OFFEN;
1110   default:
1111     return -1;
1112   }
1113 }
1114 
1115 static int getOffenMUBUFLoad(unsigned Opc) {
1116   switch (Opc) {
1117   case AMDGPU::BUFFER_LOAD_DWORD_OFFSET:
1118     return AMDGPU::BUFFER_LOAD_DWORD_OFFEN;
1119   case AMDGPU::BUFFER_LOAD_UBYTE_OFFSET:
1120     return AMDGPU::BUFFER_LOAD_UBYTE_OFFEN;
1121   case AMDGPU::BUFFER_LOAD_SBYTE_OFFSET:
1122     return AMDGPU::BUFFER_LOAD_SBYTE_OFFEN;
1123   case AMDGPU::BUFFER_LOAD_USHORT_OFFSET:
1124     return AMDGPU::BUFFER_LOAD_USHORT_OFFEN;
1125   case AMDGPU::BUFFER_LOAD_SSHORT_OFFSET:
1126     return AMDGPU::BUFFER_LOAD_SSHORT_OFFEN;
1127   case AMDGPU::BUFFER_LOAD_DWORDX2_OFFSET:
1128     return AMDGPU::BUFFER_LOAD_DWORDX2_OFFEN;
1129   case AMDGPU::BUFFER_LOAD_DWORDX3_OFFSET:
1130     return AMDGPU::BUFFER_LOAD_DWORDX3_OFFEN;
1131   case AMDGPU::BUFFER_LOAD_DWORDX4_OFFSET:
1132     return AMDGPU::BUFFER_LOAD_DWORDX4_OFFEN;
1133   case AMDGPU::BUFFER_LOAD_UBYTE_D16_OFFSET:
1134     return AMDGPU::BUFFER_LOAD_UBYTE_D16_OFFEN;
1135   case AMDGPU::BUFFER_LOAD_UBYTE_D16_HI_OFFSET:
1136     return AMDGPU::BUFFER_LOAD_UBYTE_D16_HI_OFFEN;
1137   case AMDGPU::BUFFER_LOAD_SBYTE_D16_OFFSET:
1138     return AMDGPU::BUFFER_LOAD_SBYTE_D16_OFFEN;
1139   case AMDGPU::BUFFER_LOAD_SBYTE_D16_HI_OFFSET:
1140     return AMDGPU::BUFFER_LOAD_SBYTE_D16_HI_OFFEN;
1141   case AMDGPU::BUFFER_LOAD_SHORT_D16_OFFSET:
1142     return AMDGPU::BUFFER_LOAD_SHORT_D16_OFFEN;
1143   case AMDGPU::BUFFER_LOAD_SHORT_D16_HI_OFFSET:
1144     return AMDGPU::BUFFER_LOAD_SHORT_D16_HI_OFFEN;
1145   default:
1146     return -1;
1147   }
1148 }
1149 
1150 static MachineInstrBuilder spillVGPRtoAGPR(const GCNSubtarget &ST,
1151                                            MachineBasicBlock &MBB,
1152                                            MachineBasicBlock::iterator MI,
1153                                            int Index, unsigned Lane,
1154                                            unsigned ValueReg, bool IsKill) {
1155   MachineFunction *MF = MBB.getParent();
1156   SIMachineFunctionInfo *MFI = MF->getInfo<SIMachineFunctionInfo>();
1157   const SIInstrInfo *TII = ST.getInstrInfo();
1158 
1159   MCPhysReg Reg = MFI->getVGPRToAGPRSpill(Index, Lane);
1160 
1161   if (Reg == AMDGPU::NoRegister)
1162     return MachineInstrBuilder();
1163 
1164   bool IsStore = MI->mayStore();
1165   MachineRegisterInfo &MRI = MF->getRegInfo();
1166   auto *TRI = static_cast<const SIRegisterInfo*>(MRI.getTargetRegisterInfo());
1167 
1168   unsigned Dst = IsStore ? Reg : ValueReg;
1169   unsigned Src = IsStore ? ValueReg : Reg;
1170   bool IsVGPR = TRI->isVGPR(MRI, Reg);
1171   DebugLoc DL = MI->getDebugLoc();
1172   if (IsVGPR == TRI->isVGPR(MRI, ValueReg)) {
1173     // Spiller during regalloc may restore a spilled register to its superclass.
1174     // It could result in AGPR spills restored to VGPRs or the other way around,
1175     // making the src and dst with identical regclasses at this point. It just
1176     // needs a copy in such cases.
1177     auto CopyMIB = BuildMI(MBB, MI, DL, TII->get(AMDGPU::COPY), Dst)
1178                        .addReg(Src, getKillRegState(IsKill));
1179     CopyMIB->setAsmPrinterFlag(MachineInstr::ReloadReuse);
1180     return CopyMIB;
1181   }
1182   unsigned Opc = (IsStore ^ IsVGPR) ? AMDGPU::V_ACCVGPR_WRITE_B32_e64
1183                                     : AMDGPU::V_ACCVGPR_READ_B32_e64;
1184 
1185   auto MIB = BuildMI(MBB, MI, DL, TII->get(Opc), Dst)
1186                  .addReg(Src, getKillRegState(IsKill));
1187   MIB->setAsmPrinterFlag(MachineInstr::ReloadReuse);
1188   return MIB;
1189 }
1190 
1191 // This differs from buildSpillLoadStore by only scavenging a VGPR. It does not
1192 // need to handle the case where an SGPR may need to be spilled while spilling.
1193 static bool buildMUBUFOffsetLoadStore(const GCNSubtarget &ST,
1194                                       MachineFrameInfo &MFI,
1195                                       MachineBasicBlock::iterator MI,
1196                                       int Index,
1197                                       int64_t Offset) {
1198   const SIInstrInfo *TII = ST.getInstrInfo();
1199   MachineBasicBlock *MBB = MI->getParent();
1200   const DebugLoc &DL = MI->getDebugLoc();
1201   bool IsStore = MI->mayStore();
1202 
1203   unsigned Opc = MI->getOpcode();
1204   int LoadStoreOp = IsStore ?
1205     getOffsetMUBUFStore(Opc) : getOffsetMUBUFLoad(Opc);
1206   if (LoadStoreOp == -1)
1207     return false;
1208 
1209   const MachineOperand *Reg = TII->getNamedOperand(*MI, AMDGPU::OpName::vdata);
1210   if (spillVGPRtoAGPR(ST, *MBB, MI, Index, 0, Reg->getReg(), false).getInstr())
1211     return true;
1212 
1213   MachineInstrBuilder NewMI =
1214       BuildMI(*MBB, MI, DL, TII->get(LoadStoreOp))
1215           .add(*Reg)
1216           .add(*TII->getNamedOperand(*MI, AMDGPU::OpName::srsrc))
1217           .add(*TII->getNamedOperand(*MI, AMDGPU::OpName::soffset))
1218           .addImm(Offset)
1219           .addImm(0) // cpol
1220           .addImm(0) // tfe
1221           .addImm(0) // swz
1222           .cloneMemRefs(*MI);
1223 
1224   const MachineOperand *VDataIn = TII->getNamedOperand(*MI,
1225                                                        AMDGPU::OpName::vdata_in);
1226   if (VDataIn)
1227     NewMI.add(*VDataIn);
1228   return true;
1229 }
1230 
1231 static unsigned getFlatScratchSpillOpcode(const SIInstrInfo *TII,
1232                                           unsigned LoadStoreOp,
1233                                           unsigned EltSize) {
1234   bool IsStore = TII->get(LoadStoreOp).mayStore();
1235   bool HasVAddr = AMDGPU::getNamedOperandIdx(LoadStoreOp, AMDGPU::OpName::vaddr) != -1;
1236   bool UseST =
1237     !HasVAddr &&
1238     AMDGPU::getNamedOperandIdx(LoadStoreOp, AMDGPU::OpName::saddr) < 0;
1239 
1240   switch (EltSize) {
1241   case 4:
1242     LoadStoreOp = IsStore ? AMDGPU::SCRATCH_STORE_DWORD_SADDR
1243                           : AMDGPU::SCRATCH_LOAD_DWORD_SADDR;
1244     break;
1245   case 8:
1246     LoadStoreOp = IsStore ? AMDGPU::SCRATCH_STORE_DWORDX2_SADDR
1247                           : AMDGPU::SCRATCH_LOAD_DWORDX2_SADDR;
1248     break;
1249   case 12:
1250     LoadStoreOp = IsStore ? AMDGPU::SCRATCH_STORE_DWORDX3_SADDR
1251                           : AMDGPU::SCRATCH_LOAD_DWORDX3_SADDR;
1252     break;
1253   case 16:
1254     LoadStoreOp = IsStore ? AMDGPU::SCRATCH_STORE_DWORDX4_SADDR
1255                           : AMDGPU::SCRATCH_LOAD_DWORDX4_SADDR;
1256     break;
1257   default:
1258     llvm_unreachable("Unexpected spill load/store size!");
1259   }
1260 
1261   if (HasVAddr)
1262     LoadStoreOp = AMDGPU::getFlatScratchInstSVfromSS(LoadStoreOp);
1263   else if (UseST)
1264     LoadStoreOp = AMDGPU::getFlatScratchInstSTfromSS(LoadStoreOp);
1265 
1266   return LoadStoreOp;
1267 }
1268 
1269 void SIRegisterInfo::buildSpillLoadStore(
1270     MachineBasicBlock &MBB, MachineBasicBlock::iterator MI, const DebugLoc &DL,
1271     unsigned LoadStoreOp, int Index, Register ValueReg, bool IsKill,
1272     MCRegister ScratchOffsetReg, int64_t InstOffset, MachineMemOperand *MMO,
1273     RegScavenger *RS, LivePhysRegs *LiveRegs) const {
1274   assert((!RS || !LiveRegs) && "Only RS or LiveRegs can be set but not both");
1275 
1276   MachineFunction *MF = MBB.getParent();
1277   const SIInstrInfo *TII = ST.getInstrInfo();
1278   const MachineFrameInfo &MFI = MF->getFrameInfo();
1279   const SIMachineFunctionInfo *FuncInfo = MF->getInfo<SIMachineFunctionInfo>();
1280 
1281   const MCInstrDesc *Desc = &TII->get(LoadStoreOp);
1282   bool IsStore = Desc->mayStore();
1283   bool IsFlat = TII->isFLATScratch(LoadStoreOp);
1284 
1285   bool CanClobberSCC = false;
1286   bool Scavenged = false;
1287   MCRegister SOffset = ScratchOffsetReg;
1288 
1289   const TargetRegisterClass *RC = getRegClassForReg(MF->getRegInfo(), ValueReg);
1290   // On gfx90a+ AGPR is a regular VGPR acceptable for loads and stores.
1291   const bool IsAGPR = !ST.hasGFX90AInsts() && isAGPRClass(RC);
1292   const unsigned RegWidth = AMDGPU::getRegBitWidth(RC->getID()) / 8;
1293 
1294   // Always use 4 byte operations for AGPRs because we need to scavenge
1295   // a temporary VGPR.
1296   unsigned EltSize = (IsFlat && !IsAGPR) ? std::min(RegWidth, 16u) : 4u;
1297   unsigned NumSubRegs = RegWidth / EltSize;
1298   unsigned Size = NumSubRegs * EltSize;
1299   unsigned RemSize = RegWidth - Size;
1300   unsigned NumRemSubRegs = RemSize ? 1 : 0;
1301   int64_t Offset = InstOffset + MFI.getObjectOffset(Index);
1302   int64_t MaterializedOffset = Offset;
1303 
1304   int64_t MaxOffset = Offset + Size + RemSize - EltSize;
1305   int64_t ScratchOffsetRegDelta = 0;
1306 
1307   if (IsFlat && EltSize > 4) {
1308     LoadStoreOp = getFlatScratchSpillOpcode(TII, LoadStoreOp, EltSize);
1309     Desc = &TII->get(LoadStoreOp);
1310   }
1311 
1312   Align Alignment = MFI.getObjectAlign(Index);
1313   const MachinePointerInfo &BasePtrInfo = MMO->getPointerInfo();
1314 
1315   assert((IsFlat || ((Offset % EltSize) == 0)) &&
1316          "unexpected VGPR spill offset");
1317 
1318   // Track a VGPR to use for a constant offset we need to materialize.
1319   Register TmpOffsetVGPR;
1320 
1321   // Track a VGPR to use as an intermediate value.
1322   Register TmpIntermediateVGPR;
1323   bool UseVGPROffset = false;
1324 
1325   // Materialize a VGPR offset required for the given SGPR/VGPR/Immediate
1326   // combination.
1327   auto MaterializeVOffset = [&](Register SGPRBase, Register TmpVGPR,
1328                                 int64_t VOffset) {
1329     // We are using a VGPR offset
1330     if (IsFlat && SGPRBase) {
1331       // We only have 1 VGPR offset, or 1 SGPR offset. We don't have a free
1332       // SGPR, so perform the add as vector.
1333       // We don't need a base SGPR in the kernel.
1334 
1335       if (ST.getConstantBusLimit(AMDGPU::V_ADD_U32_e64) >= 2) {
1336         BuildMI(MBB, MI, DL, TII->get(AMDGPU::V_ADD_U32_e64), TmpVGPR)
1337           .addReg(SGPRBase)
1338           .addImm(VOffset)
1339           .addImm(0); // clamp
1340       } else {
1341         BuildMI(MBB, MI, DL, TII->get(AMDGPU::V_MOV_B32_e32), TmpVGPR)
1342           .addReg(SGPRBase);
1343         BuildMI(MBB, MI, DL, TII->get(AMDGPU::V_ADD_U32_e32), TmpVGPR)
1344           .addImm(VOffset)
1345           .addReg(TmpOffsetVGPR);
1346       }
1347     } else {
1348       assert(TmpOffsetVGPR);
1349       BuildMI(MBB, MI, DL, TII->get(AMDGPU::V_MOV_B32_e32), TmpVGPR)
1350         .addImm(VOffset);
1351     }
1352   };
1353 
1354   bool IsOffsetLegal =
1355       IsFlat ? TII->isLegalFLATOffset(MaxOffset, AMDGPUAS::PRIVATE_ADDRESS,
1356                                       SIInstrFlags::FlatScratch)
1357              : SIInstrInfo::isLegalMUBUFImmOffset(MaxOffset);
1358   if (!IsOffsetLegal || (IsFlat && !SOffset && !ST.hasFlatScratchSTMode())) {
1359     SOffset = MCRegister();
1360 
1361     // We don't have access to the register scavenger if this function is called
1362     // during  PEI::scavengeFrameVirtualRegs() so use LiveRegs in this case.
1363     // TODO: Clobbering SCC is not necessary for scratch instructions in the
1364     // entry.
1365     if (RS) {
1366       SOffset = RS->scavengeRegister(&AMDGPU::SGPR_32RegClass, MI, 0, false);
1367 
1368       // Piggy back on the liveness scan we just did see if SCC is dead.
1369       CanClobberSCC = !RS->isRegUsed(AMDGPU::SCC);
1370     } else if (LiveRegs) {
1371       CanClobberSCC = !LiveRegs->contains(AMDGPU::SCC);
1372       for (MCRegister Reg : AMDGPU::SGPR_32RegClass) {
1373         if (LiveRegs->available(MF->getRegInfo(), Reg)) {
1374           SOffset = Reg;
1375           break;
1376         }
1377       }
1378     }
1379 
1380     if (ScratchOffsetReg != AMDGPU::NoRegister && !CanClobberSCC)
1381       SOffset = Register();
1382 
1383     if (!SOffset) {
1384       UseVGPROffset = true;
1385 
1386       if (RS) {
1387         TmpOffsetVGPR = RS->scavengeRegister(&AMDGPU::VGPR_32RegClass, MI, 0);
1388       } else {
1389         assert(LiveRegs);
1390         for (MCRegister Reg : AMDGPU::VGPR_32RegClass) {
1391           if (LiveRegs->available(MF->getRegInfo(), Reg)) {
1392             TmpOffsetVGPR = Reg;
1393             break;
1394           }
1395         }
1396       }
1397 
1398       assert(TmpOffsetVGPR);
1399     } else if (!SOffset && CanClobberSCC) {
1400       // There are no free SGPRs, and since we are in the process of spilling
1401       // VGPRs too.  Since we need a VGPR in order to spill SGPRs (this is true
1402       // on SI/CI and on VI it is true until we implement spilling using scalar
1403       // stores), we have no way to free up an SGPR.  Our solution here is to
1404       // add the offset directly to the ScratchOffset or StackPtrOffset
1405       // register, and then subtract the offset after the spill to return the
1406       // register to it's original value.
1407 
1408       // TODO: If we don't have to do an emergency stack slot spill, converting
1409       // to use the VGPR offset is fewer instructions.
1410       if (!ScratchOffsetReg)
1411         ScratchOffsetReg = FuncInfo->getStackPtrOffsetReg();
1412       SOffset = ScratchOffsetReg;
1413       ScratchOffsetRegDelta = Offset;
1414     } else {
1415       Scavenged = true;
1416     }
1417 
1418     // We currently only support spilling VGPRs to EltSize boundaries, meaning
1419     // we can simplify the adjustment of Offset here to just scale with
1420     // WavefrontSize.
1421     if (!IsFlat && !UseVGPROffset)
1422       Offset *= ST.getWavefrontSize();
1423 
1424     if (!UseVGPROffset && !SOffset)
1425       report_fatal_error("could not scavenge SGPR to spill in entry function");
1426 
1427     if (UseVGPROffset) {
1428       // We are using a VGPR offset
1429       MaterializeVOffset(ScratchOffsetReg, TmpOffsetVGPR, Offset);
1430     } else if (ScratchOffsetReg == AMDGPU::NoRegister) {
1431       BuildMI(MBB, MI, DL, TII->get(AMDGPU::S_MOV_B32), SOffset).addImm(Offset);
1432     } else {
1433       assert(Offset != 0);
1434       auto Add = BuildMI(MBB, MI, DL, TII->get(AMDGPU::S_ADD_I32), SOffset)
1435           .addReg(ScratchOffsetReg)
1436           .addImm(Offset);
1437       Add->getOperand(3).setIsDead(); // Mark SCC as dead.
1438     }
1439 
1440     Offset = 0;
1441   }
1442 
1443   if (IsFlat && SOffset == AMDGPU::NoRegister) {
1444     assert(AMDGPU::getNamedOperandIdx(LoadStoreOp, AMDGPU::OpName::vaddr) < 0
1445            && "Unexpected vaddr for flat scratch with a FI operand");
1446 
1447     if (UseVGPROffset) {
1448       LoadStoreOp = AMDGPU::getFlatScratchInstSVfromSS(LoadStoreOp);
1449     } else {
1450       assert(ST.hasFlatScratchSTMode());
1451       LoadStoreOp = AMDGPU::getFlatScratchInstSTfromSS(LoadStoreOp);
1452     }
1453 
1454     Desc = &TII->get(LoadStoreOp);
1455   }
1456 
1457   for (unsigned i = 0, e = NumSubRegs + NumRemSubRegs, RegOffset = 0; i != e;
1458        ++i, RegOffset += EltSize) {
1459     if (i == NumSubRegs) {
1460       EltSize = RemSize;
1461       LoadStoreOp = getFlatScratchSpillOpcode(TII, LoadStoreOp, EltSize);
1462     }
1463     Desc = &TII->get(LoadStoreOp);
1464 
1465     if (!IsFlat && UseVGPROffset) {
1466       int NewLoadStoreOp = IsStore ? getOffenMUBUFStore(LoadStoreOp)
1467                                    : getOffenMUBUFLoad(LoadStoreOp);
1468       Desc = &TII->get(NewLoadStoreOp);
1469     }
1470 
1471     if (UseVGPROffset && TmpOffsetVGPR == TmpIntermediateVGPR) {
1472       // If we are spilling an AGPR beyond the range of the memory instruction
1473       // offset and need to use a VGPR offset, we ideally have at least 2
1474       // scratch VGPRs. If we don't have a second free VGPR without spilling,
1475       // recycle the VGPR used for the offset which requires resetting after
1476       // each subregister.
1477 
1478       MaterializeVOffset(ScratchOffsetReg, TmpOffsetVGPR, MaterializedOffset);
1479     }
1480 
1481     unsigned NumRegs = EltSize / 4;
1482     Register SubReg = e == 1
1483             ? ValueReg
1484             : Register(getSubReg(ValueReg,
1485                                  getSubRegFromChannel(RegOffset / 4, NumRegs)));
1486 
1487     unsigned SOffsetRegState = 0;
1488     unsigned SrcDstRegState = getDefRegState(!IsStore);
1489     const bool IsLastSubReg = i + 1 == e;
1490     if (IsLastSubReg) {
1491       SOffsetRegState |= getKillRegState(Scavenged);
1492       // The last implicit use carries the "Kill" flag.
1493       SrcDstRegState |= getKillRegState(IsKill);
1494     }
1495 
1496     // Make sure the whole register is defined if there are undef components by
1497     // adding an implicit def of the super-reg on the first instruction.
1498     bool NeedSuperRegDef = e > 1 && IsStore && i == 0;
1499     bool NeedSuperRegImpOperand = e > 1;
1500 
1501     // Remaining element size to spill into memory after some parts of it
1502     // spilled into either AGPRs or VGPRs.
1503     unsigned RemEltSize = EltSize;
1504 
1505     // AGPRs to spill VGPRs and vice versa are allocated in a reverse order,
1506     // starting from the last lane. In case if a register cannot be completely
1507     // spilled into another register that will ensure its alignment does not
1508     // change. For targets with VGPR alignment requirement this is important
1509     // in case of flat scratch usage as we might get a scratch_load or
1510     // scratch_store of an unaligned register otherwise.
1511     for (int LaneS = (RegOffset + EltSize) / 4 - 1, Lane = LaneS,
1512              LaneE = RegOffset / 4;
1513          Lane >= LaneE; --Lane) {
1514       bool IsSubReg = e > 1 || EltSize > 4;
1515       Register Sub = IsSubReg
1516              ? Register(getSubReg(ValueReg, getSubRegFromChannel(Lane)))
1517              : ValueReg;
1518       auto MIB = spillVGPRtoAGPR(ST, MBB, MI, Index, Lane, Sub, IsKill);
1519       if (!MIB.getInstr())
1520         break;
1521       if (NeedSuperRegDef || (IsSubReg && IsStore && Lane == LaneS && !i)) {
1522         MIB.addReg(ValueReg, RegState::ImplicitDefine);
1523         NeedSuperRegDef = false;
1524       }
1525       if (IsSubReg || NeedSuperRegImpOperand) {
1526         NeedSuperRegImpOperand = true;
1527         unsigned State = SrcDstRegState;
1528         if (Lane != LaneE)
1529           State &= ~RegState::Kill;
1530         MIB.addReg(ValueReg, RegState::Implicit | State);
1531       }
1532       RemEltSize -= 4;
1533     }
1534 
1535     if (!RemEltSize) // Fully spilled into AGPRs.
1536       continue;
1537 
1538     if (RemEltSize != EltSize) { // Partially spilled to AGPRs
1539       assert(IsFlat && EltSize > 4);
1540 
1541       unsigned NumRegs = RemEltSize / 4;
1542       SubReg = Register(getSubReg(ValueReg,
1543                         getSubRegFromChannel(RegOffset / 4, NumRegs)));
1544       unsigned Opc = getFlatScratchSpillOpcode(TII, LoadStoreOp, RemEltSize);
1545       Desc = &TII->get(Opc);
1546     }
1547 
1548     unsigned FinalReg = SubReg;
1549 
1550     if (IsAGPR) {
1551       assert(EltSize == 4);
1552 
1553       if (!TmpIntermediateVGPR) {
1554         assert(MF->getRegInfo().isReserved(AMDGPU::VGPR32));
1555         TmpIntermediateVGPR = AMDGPU::VGPR32;
1556       }
1557       if (IsStore) {
1558         auto AccRead = BuildMI(MBB, MI, DL,
1559                                TII->get(AMDGPU::V_ACCVGPR_READ_B32_e64),
1560                                TmpIntermediateVGPR)
1561                            .addReg(SubReg, getKillRegState(IsKill));
1562         if (NeedSuperRegDef)
1563           AccRead.addReg(ValueReg, RegState::ImplicitDefine);
1564         AccRead->setAsmPrinterFlag(MachineInstr::ReloadReuse);
1565       }
1566       SubReg = TmpIntermediateVGPR;
1567     } else if (UseVGPROffset) {
1568       // FIXME: change to scavengeRegisterBackwards()
1569       if (!TmpOffsetVGPR) {
1570         TmpOffsetVGPR = RS->scavengeRegister(&AMDGPU::VGPR_32RegClass, MI, 0);
1571         RS->setRegUsed(TmpOffsetVGPR);
1572       }
1573     }
1574 
1575     MachinePointerInfo PInfo = BasePtrInfo.getWithOffset(RegOffset);
1576     MachineMemOperand *NewMMO =
1577         MF->getMachineMemOperand(PInfo, MMO->getFlags(), RemEltSize,
1578                                  commonAlignment(Alignment, RegOffset));
1579 
1580     auto MIB =
1581         BuildMI(MBB, MI, DL, *Desc)
1582             .addReg(SubReg, getDefRegState(!IsStore) | getKillRegState(IsKill));
1583 
1584     if (UseVGPROffset) {
1585       // For an AGPR spill, we reuse the same temp VGPR for the offset and the
1586       // intermediate accvgpr_write.
1587       MIB.addReg(TmpOffsetVGPR, getKillRegState(IsLastSubReg && !IsAGPR));
1588     }
1589 
1590     if (!IsFlat)
1591       MIB.addReg(FuncInfo->getScratchRSrcReg());
1592 
1593     if (SOffset == AMDGPU::NoRegister) {
1594       if (!IsFlat) {
1595         if (UseVGPROffset && ScratchOffsetReg) {
1596           assert(!FuncInfo->isEntryFunction());
1597           MIB.addReg(ScratchOffsetReg);
1598         } else {
1599           assert(FuncInfo->isEntryFunction());
1600           MIB.addImm(0);
1601         }
1602       }
1603     } else {
1604       MIB.addReg(SOffset, SOffsetRegState);
1605     }
1606     MIB.addImm(Offset + RegOffset)
1607        .addImm(0); // cpol
1608     if (!IsFlat)
1609       MIB.addImm(0)  // tfe
1610          .addImm(0); // swz
1611     MIB.addMemOperand(NewMMO);
1612 
1613     if (!IsAGPR && NeedSuperRegDef)
1614       MIB.addReg(ValueReg, RegState::ImplicitDefine);
1615 
1616     if (!IsStore && IsAGPR && TmpIntermediateVGPR != AMDGPU::NoRegister) {
1617       MIB = BuildMI(MBB, MI, DL, TII->get(AMDGPU::V_ACCVGPR_WRITE_B32_e64),
1618                     FinalReg)
1619                 .addReg(TmpIntermediateVGPR, RegState::Kill);
1620       MIB->setAsmPrinterFlag(MachineInstr::ReloadReuse);
1621     }
1622 
1623     if (NeedSuperRegImpOperand)
1624       MIB.addReg(ValueReg, RegState::Implicit | SrcDstRegState);
1625   }
1626 
1627   if (ScratchOffsetRegDelta != 0) {
1628     // Subtract the offset we added to the ScratchOffset register.
1629     BuildMI(MBB, MI, DL, TII->get(AMDGPU::S_ADD_I32), SOffset)
1630         .addReg(SOffset)
1631         .addImm(-ScratchOffsetRegDelta);
1632   }
1633 }
1634 
1635 void SIRegisterInfo::buildVGPRSpillLoadStore(SGPRSpillBuilder &SB, int Index,
1636                                              int Offset, bool IsLoad,
1637                                              bool IsKill) const {
1638   // Load/store VGPR
1639   MachineFrameInfo &FrameInfo = SB.MF.getFrameInfo();
1640   assert(FrameInfo.getStackID(Index) != TargetStackID::SGPRSpill);
1641 
1642   Register FrameReg =
1643       FrameInfo.isFixedObjectIndex(Index) && hasBasePointer(SB.MF)
1644           ? getBaseRegister()
1645           : getFrameRegister(SB.MF);
1646 
1647   Align Alignment = FrameInfo.getObjectAlign(Index);
1648   MachinePointerInfo PtrInfo = MachinePointerInfo::getFixedStack(SB.MF, Index);
1649   MachineMemOperand *MMO = SB.MF.getMachineMemOperand(
1650       PtrInfo, IsLoad ? MachineMemOperand::MOLoad : MachineMemOperand::MOStore,
1651       SB.EltSize, Alignment);
1652 
1653   if (IsLoad) {
1654     unsigned Opc = ST.enableFlatScratch() ? AMDGPU::SCRATCH_LOAD_DWORD_SADDR
1655                                           : AMDGPU::BUFFER_LOAD_DWORD_OFFSET;
1656     buildSpillLoadStore(*SB.MBB, SB.MI, SB.DL, Opc, Index, SB.TmpVGPR, false,
1657                         FrameReg, Offset * SB.EltSize, MMO, SB.RS);
1658   } else {
1659     unsigned Opc = ST.enableFlatScratch() ? AMDGPU::SCRATCH_STORE_DWORD_SADDR
1660                                           : AMDGPU::BUFFER_STORE_DWORD_OFFSET;
1661     buildSpillLoadStore(*SB.MBB, SB.MI, SB.DL, Opc, Index, SB.TmpVGPR, IsKill,
1662                         FrameReg, Offset * SB.EltSize, MMO, SB.RS);
1663     // This only ever adds one VGPR spill
1664     SB.MFI.addToSpilledVGPRs(1);
1665   }
1666 }
1667 
1668 bool SIRegisterInfo::spillSGPR(MachineBasicBlock::iterator MI,
1669                                int Index,
1670                                RegScavenger *RS,
1671                                LiveIntervals *LIS,
1672                                bool OnlyToVGPR) const {
1673   SGPRSpillBuilder SB(*this, *ST.getInstrInfo(), isWave32, MI, Index, RS);
1674 
1675   ArrayRef<SIMachineFunctionInfo::SpilledReg> VGPRSpills =
1676       SB.MFI.getSGPRToVGPRSpills(Index);
1677   bool SpillToVGPR = !VGPRSpills.empty();
1678   if (OnlyToVGPR && !SpillToVGPR)
1679     return false;
1680 
1681   assert(SpillToVGPR || (SB.SuperReg != SB.MFI.getStackPtrOffsetReg() &&
1682                          SB.SuperReg != SB.MFI.getFrameOffsetReg()));
1683 
1684   if (SpillToVGPR) {
1685 
1686     assert(SB.NumSubRegs == VGPRSpills.size() &&
1687            "Num of VGPR lanes should be equal to num of SGPRs spilled");
1688 
1689     for (unsigned i = 0, e = SB.NumSubRegs; i < e; ++i) {
1690       Register SubReg =
1691           SB.NumSubRegs == 1
1692               ? SB.SuperReg
1693               : Register(getSubReg(SB.SuperReg, SB.SplitParts[i]));
1694       SIMachineFunctionInfo::SpilledReg Spill = VGPRSpills[i];
1695 
1696       bool UseKill = SB.IsKill && i == SB.NumSubRegs - 1;
1697 
1698       // Mark the "old value of vgpr" input undef only if this is the first sgpr
1699       // spill to this specific vgpr in the first basic block.
1700       auto MIB = BuildMI(*SB.MBB, MI, SB.DL,
1701                          SB.TII.get(AMDGPU::V_WRITELANE_B32), Spill.VGPR)
1702                      .addReg(SubReg, getKillRegState(UseKill))
1703                      .addImm(Spill.Lane)
1704                      .addReg(Spill.VGPR);
1705       if (LIS) {
1706         if (i == 0)
1707           LIS->ReplaceMachineInstrInMaps(*MI, *MIB);
1708         else
1709           LIS->InsertMachineInstrInMaps(*MIB);
1710       }
1711 
1712       if (i == 0 && SB.NumSubRegs > 1) {
1713         // We may be spilling a super-register which is only partially defined,
1714         // and need to ensure later spills think the value is defined.
1715         MIB.addReg(SB.SuperReg, RegState::ImplicitDefine);
1716       }
1717 
1718       if (SB.NumSubRegs > 1)
1719         MIB.addReg(SB.SuperReg, getKillRegState(UseKill) | RegState::Implicit);
1720 
1721       // FIXME: Since this spills to another register instead of an actual
1722       // frame index, we should delete the frame index when all references to
1723       // it are fixed.
1724     }
1725   } else {
1726     SB.prepare();
1727 
1728     // SubReg carries the "Kill" flag when SubReg == SB.SuperReg.
1729     unsigned SubKillState = getKillRegState((SB.NumSubRegs == 1) && SB.IsKill);
1730 
1731     // Per VGPR helper data
1732     auto PVD = SB.getPerVGPRData();
1733 
1734     for (unsigned Offset = 0; Offset < PVD.NumVGPRs; ++Offset) {
1735       unsigned TmpVGPRFlags = RegState::Undef;
1736 
1737       // Write sub registers into the VGPR
1738       for (unsigned i = Offset * PVD.PerVGPR,
1739                     e = std::min((Offset + 1) * PVD.PerVGPR, SB.NumSubRegs);
1740            i < e; ++i) {
1741         Register SubReg =
1742             SB.NumSubRegs == 1
1743                 ? SB.SuperReg
1744                 : Register(getSubReg(SB.SuperReg, SB.SplitParts[i]));
1745 
1746         MachineInstrBuilder WriteLane =
1747             BuildMI(*SB.MBB, MI, SB.DL, SB.TII.get(AMDGPU::V_WRITELANE_B32),
1748                     SB.TmpVGPR)
1749                 .addReg(SubReg, SubKillState)
1750                 .addImm(i % PVD.PerVGPR)
1751                 .addReg(SB.TmpVGPR, TmpVGPRFlags);
1752         TmpVGPRFlags = 0;
1753 
1754         if (LIS) {
1755           if (i == 0)
1756             LIS->ReplaceMachineInstrInMaps(*MI, *WriteLane);
1757           else
1758             LIS->InsertMachineInstrInMaps(*WriteLane);
1759         }
1760 
1761         // There could be undef components of a spilled super register.
1762         // TODO: Can we detect this and skip the spill?
1763         if (SB.NumSubRegs > 1) {
1764           // The last implicit use of the SB.SuperReg carries the "Kill" flag.
1765           unsigned SuperKillState = 0;
1766           if (i + 1 == SB.NumSubRegs)
1767             SuperKillState |= getKillRegState(SB.IsKill);
1768           WriteLane.addReg(SB.SuperReg, RegState::Implicit | SuperKillState);
1769         }
1770       }
1771 
1772       // Write out VGPR
1773       SB.readWriteTmpVGPR(Offset, /*IsLoad*/ false);
1774     }
1775 
1776     SB.restore();
1777   }
1778 
1779   MI->eraseFromParent();
1780   SB.MFI.addToSpilledSGPRs(SB.NumSubRegs);
1781 
1782   if (LIS)
1783     LIS->removeAllRegUnitsForPhysReg(SB.SuperReg);
1784 
1785   return true;
1786 }
1787 
1788 bool SIRegisterInfo::restoreSGPR(MachineBasicBlock::iterator MI,
1789                                  int Index,
1790                                  RegScavenger *RS,
1791                                  LiveIntervals *LIS,
1792                                  bool OnlyToVGPR) const {
1793   SGPRSpillBuilder SB(*this, *ST.getInstrInfo(), isWave32, MI, Index, RS);
1794 
1795   ArrayRef<SIMachineFunctionInfo::SpilledReg> VGPRSpills =
1796       SB.MFI.getSGPRToVGPRSpills(Index);
1797   bool SpillToVGPR = !VGPRSpills.empty();
1798   if (OnlyToVGPR && !SpillToVGPR)
1799     return false;
1800 
1801   if (SpillToVGPR) {
1802     for (unsigned i = 0, e = SB.NumSubRegs; i < e; ++i) {
1803       Register SubReg =
1804           SB.NumSubRegs == 1
1805               ? SB.SuperReg
1806               : Register(getSubReg(SB.SuperReg, SB.SplitParts[i]));
1807 
1808       SIMachineFunctionInfo::SpilledReg Spill = VGPRSpills[i];
1809       auto MIB = BuildMI(*SB.MBB, MI, SB.DL, SB.TII.get(AMDGPU::V_READLANE_B32),
1810                          SubReg)
1811                      .addReg(Spill.VGPR)
1812                      .addImm(Spill.Lane);
1813       if (SB.NumSubRegs > 1 && i == 0)
1814         MIB.addReg(SB.SuperReg, RegState::ImplicitDefine);
1815       if (LIS) {
1816         if (i == e - 1)
1817           LIS->ReplaceMachineInstrInMaps(*MI, *MIB);
1818         else
1819           LIS->InsertMachineInstrInMaps(*MIB);
1820       }
1821 
1822     }
1823   } else {
1824     SB.prepare();
1825 
1826     // Per VGPR helper data
1827     auto PVD = SB.getPerVGPRData();
1828 
1829     for (unsigned Offset = 0; Offset < PVD.NumVGPRs; ++Offset) {
1830       // Load in VGPR data
1831       SB.readWriteTmpVGPR(Offset, /*IsLoad*/ true);
1832 
1833       // Unpack lanes
1834       for (unsigned i = Offset * PVD.PerVGPR,
1835                     e = std::min((Offset + 1) * PVD.PerVGPR, SB.NumSubRegs);
1836            i < e; ++i) {
1837         Register SubReg =
1838             SB.NumSubRegs == 1
1839                 ? SB.SuperReg
1840                 : Register(getSubReg(SB.SuperReg, SB.SplitParts[i]));
1841 
1842         bool LastSubReg = (i + 1 == e);
1843         auto MIB = BuildMI(*SB.MBB, MI, SB.DL,
1844                            SB.TII.get(AMDGPU::V_READLANE_B32), SubReg)
1845                        .addReg(SB.TmpVGPR, getKillRegState(LastSubReg))
1846                        .addImm(i);
1847         if (SB.NumSubRegs > 1 && i == 0)
1848           MIB.addReg(SB.SuperReg, RegState::ImplicitDefine);
1849         if (LIS) {
1850           if (i == e - 1)
1851             LIS->ReplaceMachineInstrInMaps(*MI, *MIB);
1852           else
1853             LIS->InsertMachineInstrInMaps(*MIB);
1854         }
1855       }
1856     }
1857 
1858     SB.restore();
1859   }
1860 
1861   MI->eraseFromParent();
1862 
1863   if (LIS)
1864     LIS->removeAllRegUnitsForPhysReg(SB.SuperReg);
1865 
1866   return true;
1867 }
1868 
1869 bool SIRegisterInfo::spillEmergencySGPR(MachineBasicBlock::iterator MI,
1870                                         MachineBasicBlock &RestoreMBB,
1871                                         Register SGPR, RegScavenger *RS) const {
1872   SGPRSpillBuilder SB(*this, *ST.getInstrInfo(), isWave32, MI, SGPR, false, 0,
1873                       RS);
1874   SB.prepare();
1875   // Generate the spill of SGPR to SB.TmpVGPR.
1876   unsigned SubKillState = getKillRegState((SB.NumSubRegs == 1) && SB.IsKill);
1877   auto PVD = SB.getPerVGPRData();
1878   for (unsigned Offset = 0; Offset < PVD.NumVGPRs; ++Offset) {
1879     unsigned TmpVGPRFlags = RegState::Undef;
1880     // Write sub registers into the VGPR
1881     for (unsigned i = Offset * PVD.PerVGPR,
1882                   e = std::min((Offset + 1) * PVD.PerVGPR, SB.NumSubRegs);
1883          i < e; ++i) {
1884       Register SubReg =
1885           SB.NumSubRegs == 1
1886               ? SB.SuperReg
1887               : Register(getSubReg(SB.SuperReg, SB.SplitParts[i]));
1888 
1889       MachineInstrBuilder WriteLane =
1890           BuildMI(*SB.MBB, MI, SB.DL, SB.TII.get(AMDGPU::V_WRITELANE_B32),
1891                   SB.TmpVGPR)
1892               .addReg(SubReg, SubKillState)
1893               .addImm(i % PVD.PerVGPR)
1894               .addReg(SB.TmpVGPR, TmpVGPRFlags);
1895       TmpVGPRFlags = 0;
1896       // There could be undef components of a spilled super register.
1897       // TODO: Can we detect this and skip the spill?
1898       if (SB.NumSubRegs > 1) {
1899         // The last implicit use of the SB.SuperReg carries the "Kill" flag.
1900         unsigned SuperKillState = 0;
1901         if (i + 1 == SB.NumSubRegs)
1902           SuperKillState |= getKillRegState(SB.IsKill);
1903         WriteLane.addReg(SB.SuperReg, RegState::Implicit | SuperKillState);
1904       }
1905     }
1906     // Don't need to write VGPR out.
1907   }
1908 
1909   // Restore clobbered registers in the specified restore block.
1910   MI = RestoreMBB.end();
1911   SB.setMI(&RestoreMBB, MI);
1912   // Generate the restore of SGPR from SB.TmpVGPR.
1913   for (unsigned Offset = 0; Offset < PVD.NumVGPRs; ++Offset) {
1914     // Don't need to load VGPR in.
1915     // Unpack lanes
1916     for (unsigned i = Offset * PVD.PerVGPR,
1917                   e = std::min((Offset + 1) * PVD.PerVGPR, SB.NumSubRegs);
1918          i < e; ++i) {
1919       Register SubReg =
1920           SB.NumSubRegs == 1
1921               ? SB.SuperReg
1922               : Register(getSubReg(SB.SuperReg, SB.SplitParts[i]));
1923       bool LastSubReg = (i + 1 == e);
1924       auto MIB = BuildMI(*SB.MBB, MI, SB.DL, SB.TII.get(AMDGPU::V_READLANE_B32),
1925                          SubReg)
1926                      .addReg(SB.TmpVGPR, getKillRegState(LastSubReg))
1927                      .addImm(i);
1928       if (SB.NumSubRegs > 1 && i == 0)
1929         MIB.addReg(SB.SuperReg, RegState::ImplicitDefine);
1930     }
1931   }
1932   SB.restore();
1933 
1934   SB.MFI.addToSpilledSGPRs(SB.NumSubRegs);
1935   return false;
1936 }
1937 
1938 /// Special case of eliminateFrameIndex. Returns true if the SGPR was spilled to
1939 /// a VGPR and the stack slot can be safely eliminated when all other users are
1940 /// handled.
1941 bool SIRegisterInfo::eliminateSGPRToVGPRSpillFrameIndex(
1942   MachineBasicBlock::iterator MI,
1943   int FI,
1944   RegScavenger *RS,
1945   LiveIntervals *LIS) const {
1946   switch (MI->getOpcode()) {
1947   case AMDGPU::SI_SPILL_S1024_SAVE:
1948   case AMDGPU::SI_SPILL_S512_SAVE:
1949   case AMDGPU::SI_SPILL_S256_SAVE:
1950   case AMDGPU::SI_SPILL_S224_SAVE:
1951   case AMDGPU::SI_SPILL_S192_SAVE:
1952   case AMDGPU::SI_SPILL_S160_SAVE:
1953   case AMDGPU::SI_SPILL_S128_SAVE:
1954   case AMDGPU::SI_SPILL_S96_SAVE:
1955   case AMDGPU::SI_SPILL_S64_SAVE:
1956   case AMDGPU::SI_SPILL_S32_SAVE:
1957     return spillSGPR(MI, FI, RS, LIS, true);
1958   case AMDGPU::SI_SPILL_S1024_RESTORE:
1959   case AMDGPU::SI_SPILL_S512_RESTORE:
1960   case AMDGPU::SI_SPILL_S256_RESTORE:
1961   case AMDGPU::SI_SPILL_S224_RESTORE:
1962   case AMDGPU::SI_SPILL_S192_RESTORE:
1963   case AMDGPU::SI_SPILL_S160_RESTORE:
1964   case AMDGPU::SI_SPILL_S128_RESTORE:
1965   case AMDGPU::SI_SPILL_S96_RESTORE:
1966   case AMDGPU::SI_SPILL_S64_RESTORE:
1967   case AMDGPU::SI_SPILL_S32_RESTORE:
1968     return restoreSGPR(MI, FI, RS, LIS, true);
1969   default:
1970     llvm_unreachable("not an SGPR spill instruction");
1971   }
1972 }
1973 
1974 void SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
1975                                         int SPAdj, unsigned FIOperandNum,
1976                                         RegScavenger *RS) const {
1977   MachineFunction *MF = MI->getParent()->getParent();
1978   MachineBasicBlock *MBB = MI->getParent();
1979   SIMachineFunctionInfo *MFI = MF->getInfo<SIMachineFunctionInfo>();
1980   MachineFrameInfo &FrameInfo = MF->getFrameInfo();
1981   const SIInstrInfo *TII = ST.getInstrInfo();
1982   DebugLoc DL = MI->getDebugLoc();
1983 
1984   assert(SPAdj == 0 && "unhandled SP adjustment in call sequence?");
1985 
1986   MachineOperand &FIOp = MI->getOperand(FIOperandNum);
1987   int Index = MI->getOperand(FIOperandNum).getIndex();
1988 
1989   Register FrameReg = FrameInfo.isFixedObjectIndex(Index) && hasBasePointer(*MF)
1990                           ? getBaseRegister()
1991                           : getFrameRegister(*MF);
1992 
1993   switch (MI->getOpcode()) {
1994     // SGPR register spill
1995     case AMDGPU::SI_SPILL_S1024_SAVE:
1996     case AMDGPU::SI_SPILL_S512_SAVE:
1997     case AMDGPU::SI_SPILL_S256_SAVE:
1998     case AMDGPU::SI_SPILL_S224_SAVE:
1999     case AMDGPU::SI_SPILL_S192_SAVE:
2000     case AMDGPU::SI_SPILL_S160_SAVE:
2001     case AMDGPU::SI_SPILL_S128_SAVE:
2002     case AMDGPU::SI_SPILL_S96_SAVE:
2003     case AMDGPU::SI_SPILL_S64_SAVE:
2004     case AMDGPU::SI_SPILL_S32_SAVE: {
2005       spillSGPR(MI, Index, RS);
2006       break;
2007     }
2008 
2009     // SGPR register restore
2010     case AMDGPU::SI_SPILL_S1024_RESTORE:
2011     case AMDGPU::SI_SPILL_S512_RESTORE:
2012     case AMDGPU::SI_SPILL_S256_RESTORE:
2013     case AMDGPU::SI_SPILL_S224_RESTORE:
2014     case AMDGPU::SI_SPILL_S192_RESTORE:
2015     case AMDGPU::SI_SPILL_S160_RESTORE:
2016     case AMDGPU::SI_SPILL_S128_RESTORE:
2017     case AMDGPU::SI_SPILL_S96_RESTORE:
2018     case AMDGPU::SI_SPILL_S64_RESTORE:
2019     case AMDGPU::SI_SPILL_S32_RESTORE: {
2020       restoreSGPR(MI, Index, RS);
2021       break;
2022     }
2023 
2024     // VGPR register spill
2025     case AMDGPU::SI_SPILL_V1024_SAVE:
2026     case AMDGPU::SI_SPILL_V512_SAVE:
2027     case AMDGPU::SI_SPILL_V256_SAVE:
2028     case AMDGPU::SI_SPILL_V224_SAVE:
2029     case AMDGPU::SI_SPILL_V192_SAVE:
2030     case AMDGPU::SI_SPILL_V160_SAVE:
2031     case AMDGPU::SI_SPILL_V128_SAVE:
2032     case AMDGPU::SI_SPILL_V96_SAVE:
2033     case AMDGPU::SI_SPILL_V64_SAVE:
2034     case AMDGPU::SI_SPILL_V32_SAVE:
2035     case AMDGPU::SI_SPILL_A1024_SAVE:
2036     case AMDGPU::SI_SPILL_A512_SAVE:
2037     case AMDGPU::SI_SPILL_A256_SAVE:
2038     case AMDGPU::SI_SPILL_A224_SAVE:
2039     case AMDGPU::SI_SPILL_A192_SAVE:
2040     case AMDGPU::SI_SPILL_A160_SAVE:
2041     case AMDGPU::SI_SPILL_A128_SAVE:
2042     case AMDGPU::SI_SPILL_A96_SAVE:
2043     case AMDGPU::SI_SPILL_A64_SAVE:
2044     case AMDGPU::SI_SPILL_A32_SAVE:
2045     case AMDGPU::SI_SPILL_AV1024_SAVE:
2046     case AMDGPU::SI_SPILL_AV512_SAVE:
2047     case AMDGPU::SI_SPILL_AV256_SAVE:
2048     case AMDGPU::SI_SPILL_AV224_SAVE:
2049     case AMDGPU::SI_SPILL_AV192_SAVE:
2050     case AMDGPU::SI_SPILL_AV160_SAVE:
2051     case AMDGPU::SI_SPILL_AV128_SAVE:
2052     case AMDGPU::SI_SPILL_AV96_SAVE:
2053     case AMDGPU::SI_SPILL_AV64_SAVE:
2054     case AMDGPU::SI_SPILL_AV32_SAVE: {
2055       const MachineOperand *VData = TII->getNamedOperand(*MI,
2056                                                          AMDGPU::OpName::vdata);
2057       assert(TII->getNamedOperand(*MI, AMDGPU::OpName::soffset)->getReg() ==
2058              MFI->getStackPtrOffsetReg());
2059 
2060       unsigned Opc = ST.enableFlatScratch() ? AMDGPU::SCRATCH_STORE_DWORD_SADDR
2061                                             : AMDGPU::BUFFER_STORE_DWORD_OFFSET;
2062       auto *MBB = MI->getParent();
2063       buildSpillLoadStore(
2064           *MBB, MI, DL, Opc, Index, VData->getReg(), VData->isKill(), FrameReg,
2065           TII->getNamedOperand(*MI, AMDGPU::OpName::offset)->getImm(),
2066           *MI->memoperands_begin(), RS);
2067       MFI->addToSpilledVGPRs(getNumSubRegsForSpillOp(MI->getOpcode()));
2068       MI->eraseFromParent();
2069       break;
2070     }
2071     case AMDGPU::SI_SPILL_V32_RESTORE:
2072     case AMDGPU::SI_SPILL_V64_RESTORE:
2073     case AMDGPU::SI_SPILL_V96_RESTORE:
2074     case AMDGPU::SI_SPILL_V128_RESTORE:
2075     case AMDGPU::SI_SPILL_V160_RESTORE:
2076     case AMDGPU::SI_SPILL_V192_RESTORE:
2077     case AMDGPU::SI_SPILL_V224_RESTORE:
2078     case AMDGPU::SI_SPILL_V256_RESTORE:
2079     case AMDGPU::SI_SPILL_V512_RESTORE:
2080     case AMDGPU::SI_SPILL_V1024_RESTORE:
2081     case AMDGPU::SI_SPILL_A32_RESTORE:
2082     case AMDGPU::SI_SPILL_A64_RESTORE:
2083     case AMDGPU::SI_SPILL_A96_RESTORE:
2084     case AMDGPU::SI_SPILL_A128_RESTORE:
2085     case AMDGPU::SI_SPILL_A160_RESTORE:
2086     case AMDGPU::SI_SPILL_A192_RESTORE:
2087     case AMDGPU::SI_SPILL_A224_RESTORE:
2088     case AMDGPU::SI_SPILL_A256_RESTORE:
2089     case AMDGPU::SI_SPILL_A512_RESTORE:
2090     case AMDGPU::SI_SPILL_A1024_RESTORE:
2091     case AMDGPU::SI_SPILL_AV32_RESTORE:
2092     case AMDGPU::SI_SPILL_AV64_RESTORE:
2093     case AMDGPU::SI_SPILL_AV96_RESTORE:
2094     case AMDGPU::SI_SPILL_AV128_RESTORE:
2095     case AMDGPU::SI_SPILL_AV160_RESTORE:
2096     case AMDGPU::SI_SPILL_AV192_RESTORE:
2097     case AMDGPU::SI_SPILL_AV224_RESTORE:
2098     case AMDGPU::SI_SPILL_AV256_RESTORE:
2099     case AMDGPU::SI_SPILL_AV512_RESTORE:
2100     case AMDGPU::SI_SPILL_AV1024_RESTORE: {
2101       const MachineOperand *VData = TII->getNamedOperand(*MI,
2102                                                          AMDGPU::OpName::vdata);
2103       assert(TII->getNamedOperand(*MI, AMDGPU::OpName::soffset)->getReg() ==
2104              MFI->getStackPtrOffsetReg());
2105 
2106       unsigned Opc = ST.enableFlatScratch() ? AMDGPU::SCRATCH_LOAD_DWORD_SADDR
2107                                             : AMDGPU::BUFFER_LOAD_DWORD_OFFSET;
2108       auto *MBB = MI->getParent();
2109       buildSpillLoadStore(
2110           *MBB, MI, DL, Opc, Index, VData->getReg(), VData->isKill(), FrameReg,
2111           TII->getNamedOperand(*MI, AMDGPU::OpName::offset)->getImm(),
2112           *MI->memoperands_begin(), RS);
2113       MI->eraseFromParent();
2114       break;
2115     }
2116 
2117     default: {
2118       // Other access to frame index
2119       const DebugLoc &DL = MI->getDebugLoc();
2120 
2121       int64_t Offset = FrameInfo.getObjectOffset(Index);
2122       if (ST.enableFlatScratch()) {
2123         if (TII->isFLATScratch(*MI)) {
2124           assert((int16_t)FIOperandNum ==
2125                  AMDGPU::getNamedOperandIdx(MI->getOpcode(),
2126                                             AMDGPU::OpName::saddr));
2127 
2128           // The offset is always swizzled, just replace it
2129           if (FrameReg)
2130             FIOp.ChangeToRegister(FrameReg, false);
2131 
2132           if (!Offset)
2133             return;
2134 
2135           MachineOperand *OffsetOp =
2136             TII->getNamedOperand(*MI, AMDGPU::OpName::offset);
2137           int64_t NewOffset = Offset + OffsetOp->getImm();
2138           if (TII->isLegalFLATOffset(NewOffset, AMDGPUAS::PRIVATE_ADDRESS,
2139                                      SIInstrFlags::FlatScratch)) {
2140             OffsetOp->setImm(NewOffset);
2141             if (FrameReg)
2142               return;
2143             Offset = 0;
2144           }
2145 
2146           assert(!TII->getNamedOperand(*MI, AMDGPU::OpName::vaddr) &&
2147                  "Unexpected vaddr for flat scratch with a FI operand");
2148 
2149           // On GFX10 we have ST mode to use no registers for an address.
2150           // Otherwise we need to materialize 0 into an SGPR.
2151           if (!Offset && ST.hasFlatScratchSTMode()) {
2152             unsigned Opc = MI->getOpcode();
2153             unsigned NewOpc = AMDGPU::getFlatScratchInstSTfromSS(Opc);
2154             MI->RemoveOperand(
2155                 AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::saddr));
2156             MI->setDesc(TII->get(NewOpc));
2157             return;
2158           }
2159         }
2160 
2161         if (!FrameReg) {
2162           FIOp.ChangeToImmediate(Offset);
2163           if (TII->isImmOperandLegal(*MI, FIOperandNum, FIOp))
2164             return;
2165         }
2166 
2167         // We need to use register here. Check if we can use an SGPR or need
2168         // a VGPR.
2169         FIOp.ChangeToRegister(AMDGPU::M0, false);
2170         bool UseSGPR = TII->isOperandLegal(*MI, FIOperandNum, &FIOp);
2171 
2172         if (!Offset && FrameReg && UseSGPR) {
2173           FIOp.setReg(FrameReg);
2174           return;
2175         }
2176 
2177         const TargetRegisterClass *RC = UseSGPR ? &AMDGPU::SReg_32_XM0RegClass
2178                                                 : &AMDGPU::VGPR_32RegClass;
2179 
2180         Register TmpReg = RS->scavengeRegister(RC, MI, 0, !UseSGPR);
2181         FIOp.setReg(TmpReg);
2182         FIOp.setIsKill(true);
2183 
2184         if ((!FrameReg || !Offset) && TmpReg) {
2185           unsigned Opc = UseSGPR ? AMDGPU::S_MOV_B32 : AMDGPU::V_MOV_B32_e32;
2186           auto MIB = BuildMI(*MBB, MI, DL, TII->get(Opc), TmpReg);
2187           if (FrameReg)
2188             MIB.addReg(FrameReg);
2189           else
2190             MIB.addImm(Offset);
2191 
2192           return;
2193         }
2194 
2195         Register TmpSReg =
2196             UseSGPR ? TmpReg
2197                     : RS->scavengeRegister(&AMDGPU::SReg_32_XM0RegClass, MI, 0,
2198                                            !UseSGPR);
2199 
2200         // TODO: for flat scratch another attempt can be made with a VGPR index
2201         //       if no SGPRs can be scavenged.
2202         if ((!TmpSReg && !FrameReg) || (!TmpReg && !UseSGPR))
2203           report_fatal_error("Cannot scavenge register in FI elimination!");
2204 
2205         if (!TmpSReg) {
2206           // Use frame register and restore it after.
2207           TmpSReg = FrameReg;
2208           FIOp.setReg(FrameReg);
2209           FIOp.setIsKill(false);
2210         }
2211 
2212         BuildMI(*MBB, MI, DL, TII->get(AMDGPU::S_ADD_I32), TmpSReg)
2213             .addReg(FrameReg)
2214             .addImm(Offset);
2215 
2216         if (!UseSGPR)
2217           BuildMI(*MBB, MI, DL, TII->get(AMDGPU::V_MOV_B32_e32), TmpReg)
2218             .addReg(TmpSReg, RegState::Kill);
2219 
2220         if (TmpSReg == FrameReg) {
2221           // Undo frame register modification.
2222           BuildMI(*MBB, std::next(MI), DL, TII->get(AMDGPU::S_ADD_I32),
2223                   FrameReg)
2224               .addReg(FrameReg)
2225               .addImm(-Offset);
2226         }
2227 
2228         return;
2229       }
2230 
2231       bool IsMUBUF = TII->isMUBUF(*MI);
2232 
2233       if (!IsMUBUF && !MFI->isEntryFunction()) {
2234         // Convert to a swizzled stack address by scaling by the wave size.
2235         //
2236         // In an entry function/kernel the offset is already swizzled.
2237 
2238         bool IsCopy = MI->getOpcode() == AMDGPU::V_MOV_B32_e32;
2239         Register ResultReg =
2240             IsCopy ? MI->getOperand(0).getReg()
2241                    : RS->scavengeRegister(&AMDGPU::VGPR_32RegClass, MI, 0);
2242 
2243         int64_t Offset = FrameInfo.getObjectOffset(Index);
2244         if (Offset == 0) {
2245           // XXX - This never happens because of emergency scavenging slot at 0?
2246           BuildMI(*MBB, MI, DL, TII->get(AMDGPU::V_LSHRREV_B32_e64), ResultReg)
2247             .addImm(ST.getWavefrontSizeLog2())
2248             .addReg(FrameReg);
2249         } else {
2250           if (auto MIB = TII->getAddNoCarry(*MBB, MI, DL, ResultReg, *RS)) {
2251             // Reuse ResultReg in intermediate step.
2252             Register ScaledReg = ResultReg;
2253 
2254             BuildMI(*MBB, *MIB, DL, TII->get(AMDGPU::V_LSHRREV_B32_e64),
2255                     ScaledReg)
2256               .addImm(ST.getWavefrontSizeLog2())
2257               .addReg(FrameReg);
2258 
2259             const bool IsVOP2 = MIB->getOpcode() == AMDGPU::V_ADD_U32_e32;
2260 
2261             // TODO: Fold if use instruction is another add of a constant.
2262             if (IsVOP2 || AMDGPU::isInlinableLiteral32(Offset, ST.hasInv2PiInlineImm())) {
2263               // FIXME: This can fail
2264               MIB.addImm(Offset);
2265               MIB.addReg(ScaledReg, RegState::Kill);
2266               if (!IsVOP2)
2267                 MIB.addImm(0); // clamp bit
2268             } else {
2269               assert(MIB->getOpcode() == AMDGPU::V_ADD_CO_U32_e64 &&
2270                      "Need to reuse carry out register");
2271 
2272               // Use scavenged unused carry out as offset register.
2273               Register ConstOffsetReg;
2274               if (!isWave32)
2275                 ConstOffsetReg = getSubReg(MIB.getReg(1), AMDGPU::sub0);
2276               else
2277                 ConstOffsetReg = MIB.getReg(1);
2278 
2279               BuildMI(*MBB, *MIB, DL, TII->get(AMDGPU::S_MOV_B32), ConstOffsetReg)
2280                 .addImm(Offset);
2281               MIB.addReg(ConstOffsetReg, RegState::Kill);
2282               MIB.addReg(ScaledReg, RegState::Kill);
2283               MIB.addImm(0); // clamp bit
2284             }
2285           } else {
2286             // We have to produce a carry out, and there isn't a free SGPR pair
2287             // for it. We can keep the whole computation on the SALU to avoid
2288             // clobbering an additional register at the cost of an extra mov.
2289 
2290             // We may have 1 free scratch SGPR even though a carry out is
2291             // unavailable. Only one additional mov is needed.
2292             Register TmpScaledReg =
2293                 RS->scavengeRegister(&AMDGPU::SReg_32_XM0RegClass, MI, 0, false);
2294             Register ScaledReg = TmpScaledReg.isValid() ? TmpScaledReg : FrameReg;
2295 
2296             BuildMI(*MBB, MI, DL, TII->get(AMDGPU::S_LSHR_B32), ScaledReg)
2297               .addReg(FrameReg)
2298               .addImm(ST.getWavefrontSizeLog2());
2299             BuildMI(*MBB, MI, DL, TII->get(AMDGPU::S_ADD_I32), ScaledReg)
2300                 .addReg(ScaledReg, RegState::Kill)
2301                 .addImm(Offset);
2302             BuildMI(*MBB, MI, DL, TII->get(AMDGPU::COPY), ResultReg)
2303               .addReg(ScaledReg, RegState::Kill);
2304 
2305             // If there were truly no free SGPRs, we need to undo everything.
2306             if (!TmpScaledReg.isValid()) {
2307               BuildMI(*MBB, MI, DL, TII->get(AMDGPU::S_ADD_I32), ScaledReg)
2308                   .addReg(ScaledReg, RegState::Kill)
2309                   .addImm(-Offset);
2310               BuildMI(*MBB, MI, DL, TII->get(AMDGPU::S_LSHL_B32), ScaledReg)
2311                 .addReg(FrameReg)
2312                 .addImm(ST.getWavefrontSizeLog2());
2313             }
2314           }
2315         }
2316 
2317         // Don't introduce an extra copy if we're just materializing in a mov.
2318         if (IsCopy)
2319           MI->eraseFromParent();
2320         else
2321           FIOp.ChangeToRegister(ResultReg, false, false, true);
2322         return;
2323       }
2324 
2325       if (IsMUBUF) {
2326         // Disable offen so we don't need a 0 vgpr base.
2327         assert(static_cast<int>(FIOperandNum) ==
2328                AMDGPU::getNamedOperandIdx(MI->getOpcode(),
2329                                           AMDGPU::OpName::vaddr));
2330 
2331         auto &SOffset = *TII->getNamedOperand(*MI, AMDGPU::OpName::soffset);
2332         assert((SOffset.isImm() && SOffset.getImm() == 0));
2333 
2334         if (FrameReg != AMDGPU::NoRegister)
2335           SOffset.ChangeToRegister(FrameReg, false);
2336 
2337         int64_t Offset = FrameInfo.getObjectOffset(Index);
2338         int64_t OldImm
2339           = TII->getNamedOperand(*MI, AMDGPU::OpName::offset)->getImm();
2340         int64_t NewOffset = OldImm + Offset;
2341 
2342         if (SIInstrInfo::isLegalMUBUFImmOffset(NewOffset) &&
2343             buildMUBUFOffsetLoadStore(ST, FrameInfo, MI, Index, NewOffset)) {
2344           MI->eraseFromParent();
2345           return;
2346         }
2347       }
2348 
2349       // If the offset is simply too big, don't convert to a scratch wave offset
2350       // relative index.
2351 
2352       FIOp.ChangeToImmediate(Offset);
2353       if (!TII->isImmOperandLegal(*MI, FIOperandNum, FIOp)) {
2354         Register TmpReg = RS->scavengeRegister(&AMDGPU::VGPR_32RegClass, MI, 0);
2355         BuildMI(*MBB, MI, DL, TII->get(AMDGPU::V_MOV_B32_e32), TmpReg)
2356           .addImm(Offset);
2357         FIOp.ChangeToRegister(TmpReg, false, false, true);
2358       }
2359     }
2360   }
2361 }
2362 
2363 StringRef SIRegisterInfo::getRegAsmName(MCRegister Reg) const {
2364   return AMDGPUInstPrinter::getRegisterName(Reg);
2365 }
2366 
2367 static const TargetRegisterClass *
2368 getAnyVGPRClassForBitWidth(unsigned BitWidth) {
2369   if (BitWidth <= 64)
2370     return &AMDGPU::VReg_64RegClass;
2371   if (BitWidth <= 96)
2372     return &AMDGPU::VReg_96RegClass;
2373   if (BitWidth <= 128)
2374     return &AMDGPU::VReg_128RegClass;
2375   if (BitWidth <= 160)
2376     return &AMDGPU::VReg_160RegClass;
2377   if (BitWidth <= 192)
2378     return &AMDGPU::VReg_192RegClass;
2379   if (BitWidth <= 224)
2380     return &AMDGPU::VReg_224RegClass;
2381   if (BitWidth <= 256)
2382     return &AMDGPU::VReg_256RegClass;
2383   if (BitWidth <= 512)
2384     return &AMDGPU::VReg_512RegClass;
2385   if (BitWidth <= 1024)
2386     return &AMDGPU::VReg_1024RegClass;
2387 
2388   return nullptr;
2389 }
2390 
2391 static const TargetRegisterClass *
2392 getAlignedVGPRClassForBitWidth(unsigned BitWidth) {
2393   if (BitWidth <= 64)
2394     return &AMDGPU::VReg_64_Align2RegClass;
2395   if (BitWidth <= 96)
2396     return &AMDGPU::VReg_96_Align2RegClass;
2397   if (BitWidth <= 128)
2398     return &AMDGPU::VReg_128_Align2RegClass;
2399   if (BitWidth <= 160)
2400     return &AMDGPU::VReg_160_Align2RegClass;
2401   if (BitWidth <= 192)
2402     return &AMDGPU::VReg_192_Align2RegClass;
2403   if (BitWidth <= 224)
2404     return &AMDGPU::VReg_224_Align2RegClass;
2405   if (BitWidth <= 256)
2406     return &AMDGPU::VReg_256_Align2RegClass;
2407   if (BitWidth <= 512)
2408     return &AMDGPU::VReg_512_Align2RegClass;
2409   if (BitWidth <= 1024)
2410     return &AMDGPU::VReg_1024_Align2RegClass;
2411 
2412   return nullptr;
2413 }
2414 
2415 const TargetRegisterClass *
2416 SIRegisterInfo::getVGPRClassForBitWidth(unsigned BitWidth) const {
2417   if (BitWidth == 1)
2418     return &AMDGPU::VReg_1RegClass;
2419   if (BitWidth <= 16)
2420     return &AMDGPU::VGPR_LO16RegClass;
2421   if (BitWidth <= 32)
2422     return &AMDGPU::VGPR_32RegClass;
2423   return ST.needsAlignedVGPRs() ? getAlignedVGPRClassForBitWidth(BitWidth)
2424                                 : getAnyVGPRClassForBitWidth(BitWidth);
2425 }
2426 
2427 static const TargetRegisterClass *
2428 getAnyAGPRClassForBitWidth(unsigned BitWidth) {
2429   if (BitWidth <= 64)
2430     return &AMDGPU::AReg_64RegClass;
2431   if (BitWidth <= 96)
2432     return &AMDGPU::AReg_96RegClass;
2433   if (BitWidth <= 128)
2434     return &AMDGPU::AReg_128RegClass;
2435   if (BitWidth <= 160)
2436     return &AMDGPU::AReg_160RegClass;
2437   if (BitWidth <= 192)
2438     return &AMDGPU::AReg_192RegClass;
2439   if (BitWidth <= 224)
2440     return &AMDGPU::AReg_224RegClass;
2441   if (BitWidth <= 256)
2442     return &AMDGPU::AReg_256RegClass;
2443   if (BitWidth <= 512)
2444     return &AMDGPU::AReg_512RegClass;
2445   if (BitWidth <= 1024)
2446     return &AMDGPU::AReg_1024RegClass;
2447 
2448   return nullptr;
2449 }
2450 
2451 static const TargetRegisterClass *
2452 getAlignedAGPRClassForBitWidth(unsigned BitWidth) {
2453   if (BitWidth <= 64)
2454     return &AMDGPU::AReg_64_Align2RegClass;
2455   if (BitWidth <= 96)
2456     return &AMDGPU::AReg_96_Align2RegClass;
2457   if (BitWidth <= 128)
2458     return &AMDGPU::AReg_128_Align2RegClass;
2459   if (BitWidth <= 160)
2460     return &AMDGPU::AReg_160_Align2RegClass;
2461   if (BitWidth <= 192)
2462     return &AMDGPU::AReg_192_Align2RegClass;
2463   if (BitWidth <= 224)
2464     return &AMDGPU::AReg_224_Align2RegClass;
2465   if (BitWidth <= 256)
2466     return &AMDGPU::AReg_256_Align2RegClass;
2467   if (BitWidth <= 512)
2468     return &AMDGPU::AReg_512_Align2RegClass;
2469   if (BitWidth <= 1024)
2470     return &AMDGPU::AReg_1024_Align2RegClass;
2471 
2472   return nullptr;
2473 }
2474 
2475 const TargetRegisterClass *
2476 SIRegisterInfo::getAGPRClassForBitWidth(unsigned BitWidth) const {
2477   if (BitWidth <= 16)
2478     return &AMDGPU::AGPR_LO16RegClass;
2479   if (BitWidth <= 32)
2480     return &AMDGPU::AGPR_32RegClass;
2481   return ST.needsAlignedVGPRs() ? getAlignedAGPRClassForBitWidth(BitWidth)
2482                                 : getAnyAGPRClassForBitWidth(BitWidth);
2483 }
2484 
2485 static const TargetRegisterClass *
2486 getAnyVectorSuperClassForBitWidth(unsigned BitWidth) {
2487   if (BitWidth <= 64)
2488     return &AMDGPU::AV_64RegClass;
2489   if (BitWidth <= 96)
2490     return &AMDGPU::AV_96RegClass;
2491   if (BitWidth <= 128)
2492     return &AMDGPU::AV_128RegClass;
2493   if (BitWidth <= 160)
2494     return &AMDGPU::AV_160RegClass;
2495   if (BitWidth <= 192)
2496     return &AMDGPU::AV_192RegClass;
2497   if (BitWidth <= 224)
2498     return &AMDGPU::AV_224RegClass;
2499   if (BitWidth <= 256)
2500     return &AMDGPU::AV_256RegClass;
2501   if (BitWidth <= 512)
2502     return &AMDGPU::AV_512RegClass;
2503   if (BitWidth <= 1024)
2504     return &AMDGPU::AV_1024RegClass;
2505 
2506   return nullptr;
2507 }
2508 
2509 static const TargetRegisterClass *
2510 getAlignedVectorSuperClassForBitWidth(unsigned BitWidth) {
2511   if (BitWidth <= 64)
2512     return &AMDGPU::AV_64_Align2RegClass;
2513   if (BitWidth <= 96)
2514     return &AMDGPU::AV_96_Align2RegClass;
2515   if (BitWidth <= 128)
2516     return &AMDGPU::AV_128_Align2RegClass;
2517   if (BitWidth <= 160)
2518     return &AMDGPU::AV_160_Align2RegClass;
2519   if (BitWidth <= 192)
2520     return &AMDGPU::AV_192_Align2RegClass;
2521   if (BitWidth <= 224)
2522     return &AMDGPU::AV_224_Align2RegClass;
2523   if (BitWidth <= 256)
2524     return &AMDGPU::AV_256_Align2RegClass;
2525   if (BitWidth <= 512)
2526     return &AMDGPU::AV_512_Align2RegClass;
2527   if (BitWidth <= 1024)
2528     return &AMDGPU::AV_1024_Align2RegClass;
2529 
2530   return nullptr;
2531 }
2532 
2533 const TargetRegisterClass *
2534 SIRegisterInfo::getVectorSuperClassForBitWidth(unsigned BitWidth) const {
2535   if (BitWidth <= 16)
2536     return &AMDGPU::VGPR_LO16RegClass;
2537   if (BitWidth <= 32)
2538     return &AMDGPU::AV_32RegClass;
2539   return ST.needsAlignedVGPRs()
2540              ? getAlignedVectorSuperClassForBitWidth(BitWidth)
2541              : getAnyVectorSuperClassForBitWidth(BitWidth);
2542 }
2543 
2544 const TargetRegisterClass *
2545 SIRegisterInfo::getSGPRClassForBitWidth(unsigned BitWidth) {
2546   if (BitWidth <= 16)
2547     return &AMDGPU::SGPR_LO16RegClass;
2548   if (BitWidth <= 32)
2549     return &AMDGPU::SReg_32RegClass;
2550   if (BitWidth <= 64)
2551     return &AMDGPU::SReg_64RegClass;
2552   if (BitWidth <= 96)
2553     return &AMDGPU::SGPR_96RegClass;
2554   if (BitWidth <= 128)
2555     return &AMDGPU::SGPR_128RegClass;
2556   if (BitWidth <= 160)
2557     return &AMDGPU::SGPR_160RegClass;
2558   if (BitWidth <= 192)
2559     return &AMDGPU::SGPR_192RegClass;
2560   if (BitWidth <= 224)
2561     return &AMDGPU::SGPR_224RegClass;
2562   if (BitWidth <= 256)
2563     return &AMDGPU::SGPR_256RegClass;
2564   if (BitWidth <= 512)
2565     return &AMDGPU::SGPR_512RegClass;
2566   if (BitWidth <= 1024)
2567     return &AMDGPU::SGPR_1024RegClass;
2568 
2569   return nullptr;
2570 }
2571 
2572 // FIXME: This is very slow. It might be worth creating a map from physreg to
2573 // register class.
2574 const TargetRegisterClass *
2575 SIRegisterInfo::getPhysRegClass(MCRegister Reg) const {
2576   static const TargetRegisterClass *const BaseClasses[] = {
2577     &AMDGPU::VGPR_LO16RegClass,
2578     &AMDGPU::VGPR_HI16RegClass,
2579     &AMDGPU::SReg_LO16RegClass,
2580     &AMDGPU::AGPR_LO16RegClass,
2581     &AMDGPU::VGPR_32RegClass,
2582     &AMDGPU::SReg_32RegClass,
2583     &AMDGPU::AGPR_32RegClass,
2584     &AMDGPU::AGPR_32RegClass,
2585     &AMDGPU::VReg_64_Align2RegClass,
2586     &AMDGPU::VReg_64RegClass,
2587     &AMDGPU::SReg_64RegClass,
2588     &AMDGPU::AReg_64_Align2RegClass,
2589     &AMDGPU::AReg_64RegClass,
2590     &AMDGPU::VReg_96_Align2RegClass,
2591     &AMDGPU::VReg_96RegClass,
2592     &AMDGPU::SReg_96RegClass,
2593     &AMDGPU::AReg_96_Align2RegClass,
2594     &AMDGPU::AReg_96RegClass,
2595     &AMDGPU::VReg_128_Align2RegClass,
2596     &AMDGPU::VReg_128RegClass,
2597     &AMDGPU::SReg_128RegClass,
2598     &AMDGPU::AReg_128_Align2RegClass,
2599     &AMDGPU::AReg_128RegClass,
2600     &AMDGPU::VReg_160_Align2RegClass,
2601     &AMDGPU::VReg_160RegClass,
2602     &AMDGPU::SReg_160RegClass,
2603     &AMDGPU::AReg_160_Align2RegClass,
2604     &AMDGPU::AReg_160RegClass,
2605     &AMDGPU::VReg_192_Align2RegClass,
2606     &AMDGPU::VReg_192RegClass,
2607     &AMDGPU::SReg_192RegClass,
2608     &AMDGPU::AReg_192_Align2RegClass,
2609     &AMDGPU::AReg_192RegClass,
2610     &AMDGPU::VReg_224_Align2RegClass,
2611     &AMDGPU::VReg_224RegClass,
2612     &AMDGPU::SReg_224RegClass,
2613     &AMDGPU::AReg_224_Align2RegClass,
2614     &AMDGPU::AReg_224RegClass,
2615     &AMDGPU::VReg_256_Align2RegClass,
2616     &AMDGPU::VReg_256RegClass,
2617     &AMDGPU::SReg_256RegClass,
2618     &AMDGPU::AReg_256_Align2RegClass,
2619     &AMDGPU::AReg_256RegClass,
2620     &AMDGPU::VReg_512_Align2RegClass,
2621     &AMDGPU::VReg_512RegClass,
2622     &AMDGPU::SReg_512RegClass,
2623     &AMDGPU::AReg_512_Align2RegClass,
2624     &AMDGPU::AReg_512RegClass,
2625     &AMDGPU::SReg_1024RegClass,
2626     &AMDGPU::VReg_1024_Align2RegClass,
2627     &AMDGPU::VReg_1024RegClass,
2628     &AMDGPU::AReg_1024_Align2RegClass,
2629     &AMDGPU::AReg_1024RegClass,
2630     &AMDGPU::SCC_CLASSRegClass,
2631     &AMDGPU::Pseudo_SReg_32RegClass,
2632     &AMDGPU::Pseudo_SReg_128RegClass,
2633   };
2634 
2635   for (const TargetRegisterClass *BaseClass : BaseClasses) {
2636     if (BaseClass->contains(Reg)) {
2637       return BaseClass;
2638     }
2639   }
2640   return nullptr;
2641 }
2642 
2643 bool SIRegisterInfo::isSGPRReg(const MachineRegisterInfo &MRI,
2644                                Register Reg) const {
2645   const TargetRegisterClass *RC;
2646   if (Reg.isVirtual())
2647     RC = MRI.getRegClass(Reg);
2648   else
2649     RC = getPhysRegClass(Reg);
2650   return isSGPRClass(RC);
2651 }
2652 
2653 const TargetRegisterClass *
2654 SIRegisterInfo::getEquivalentVGPRClass(const TargetRegisterClass *SRC) const {
2655   unsigned Size = getRegSizeInBits(*SRC);
2656   const TargetRegisterClass *VRC = getVGPRClassForBitWidth(Size);
2657   assert(VRC && "Invalid register class size");
2658   return VRC;
2659 }
2660 
2661 const TargetRegisterClass *
2662 SIRegisterInfo::getEquivalentAGPRClass(const TargetRegisterClass *SRC) const {
2663   unsigned Size = getRegSizeInBits(*SRC);
2664   const TargetRegisterClass *ARC = getAGPRClassForBitWidth(Size);
2665   assert(ARC && "Invalid register class size");
2666   return ARC;
2667 }
2668 
2669 const TargetRegisterClass *
2670 SIRegisterInfo::getEquivalentSGPRClass(const TargetRegisterClass *VRC) const {
2671   unsigned Size = getRegSizeInBits(*VRC);
2672   if (Size == 32)
2673     return &AMDGPU::SGPR_32RegClass;
2674   const TargetRegisterClass *SRC = getSGPRClassForBitWidth(Size);
2675   assert(SRC && "Invalid register class size");
2676   return SRC;
2677 }
2678 
2679 const TargetRegisterClass *SIRegisterInfo::getSubRegClass(
2680                          const TargetRegisterClass *RC, unsigned SubIdx) const {
2681   if (SubIdx == AMDGPU::NoSubRegister)
2682     return RC;
2683 
2684   // We can assume that each lane corresponds to one 32-bit register.
2685   unsigned Size = getNumChannelsFromSubReg(SubIdx) * 32;
2686   if (isAGPRClass(RC)) {
2687     RC = getAGPRClassForBitWidth(Size);
2688   } else if (isVGPRClass(RC)) {
2689     RC = getVGPRClassForBitWidth(Size);
2690   } else if (isVectorSuperClass(RC)) {
2691     RC = getVectorSuperClassForBitWidth(Size);
2692   } else {
2693     RC = getSGPRClassForBitWidth(Size);
2694   }
2695   assert(RC && "Invalid sub-register class size");
2696   return RC;
2697 }
2698 
2699 const TargetRegisterClass *
2700 SIRegisterInfo::getCompatibleSubRegClass(const TargetRegisterClass *SuperRC,
2701                                          const TargetRegisterClass *SubRC,
2702                                          unsigned SubIdx) const {
2703   // Ensure this subregister index is aligned in the super register.
2704   const TargetRegisterClass *MatchRC =
2705       getMatchingSuperRegClass(SuperRC, SubRC, SubIdx);
2706   return MatchRC && MatchRC->hasSubClassEq(SuperRC) ? MatchRC : nullptr;
2707 }
2708 
2709 bool SIRegisterInfo::opCanUseInlineConstant(unsigned OpType) const {
2710   if (OpType >= AMDGPU::OPERAND_REG_INLINE_AC_FIRST &&
2711       OpType <= AMDGPU::OPERAND_REG_INLINE_AC_LAST)
2712     return !ST.hasMFMAInlineLiteralBug();
2713 
2714   return OpType >= AMDGPU::OPERAND_SRC_FIRST &&
2715          OpType <= AMDGPU::OPERAND_SRC_LAST;
2716 }
2717 
2718 bool SIRegisterInfo::shouldRewriteCopySrc(
2719   const TargetRegisterClass *DefRC,
2720   unsigned DefSubReg,
2721   const TargetRegisterClass *SrcRC,
2722   unsigned SrcSubReg) const {
2723   // We want to prefer the smallest register class possible, so we don't want to
2724   // stop and rewrite on anything that looks like a subregister
2725   // extract. Operations mostly don't care about the super register class, so we
2726   // only want to stop on the most basic of copies between the same register
2727   // class.
2728   //
2729   // e.g. if we have something like
2730   // %0 = ...
2731   // %1 = ...
2732   // %2 = REG_SEQUENCE %0, sub0, %1, sub1, %2, sub2
2733   // %3 = COPY %2, sub0
2734   //
2735   // We want to look through the COPY to find:
2736   //  => %3 = COPY %0
2737 
2738   // Plain copy.
2739   return getCommonSubClass(DefRC, SrcRC) != nullptr;
2740 }
2741 
2742 bool SIRegisterInfo::opCanUseLiteralConstant(unsigned OpType) const {
2743   // TODO: 64-bit operands have extending behavior from 32-bit literal.
2744   return OpType >= AMDGPU::OPERAND_REG_IMM_FIRST &&
2745          OpType <= AMDGPU::OPERAND_REG_IMM_LAST;
2746 }
2747 
2748 /// Returns a lowest register that is not used at any point in the function.
2749 ///        If all registers are used, then this function will return
2750 ///         AMDGPU::NoRegister. If \p ReserveHighestVGPR = true, then return
2751 ///         highest unused register.
2752 MCRegister SIRegisterInfo::findUnusedRegister(const MachineRegisterInfo &MRI,
2753                                               const TargetRegisterClass *RC,
2754                                               const MachineFunction &MF,
2755                                               bool ReserveHighestVGPR) const {
2756   if (ReserveHighestVGPR) {
2757     for (MCRegister Reg : reverse(*RC))
2758       if (MRI.isAllocatable(Reg) && !MRI.isPhysRegUsed(Reg))
2759         return Reg;
2760   } else {
2761     for (MCRegister Reg : *RC)
2762       if (MRI.isAllocatable(Reg) && !MRI.isPhysRegUsed(Reg))
2763         return Reg;
2764   }
2765   return MCRegister();
2766 }
2767 
2768 ArrayRef<int16_t> SIRegisterInfo::getRegSplitParts(const TargetRegisterClass *RC,
2769                                                    unsigned EltSize) const {
2770   const unsigned RegBitWidth = AMDGPU::getRegBitWidth(*RC->MC);
2771   assert(RegBitWidth >= 32 && RegBitWidth <= 1024);
2772 
2773   const unsigned RegDWORDs = RegBitWidth / 32;
2774   const unsigned EltDWORDs = EltSize / 4;
2775   assert(RegSplitParts.size() + 1 >= EltDWORDs);
2776 
2777   const std::vector<int16_t> &Parts = RegSplitParts[EltDWORDs - 1];
2778   const unsigned NumParts = RegDWORDs / EltDWORDs;
2779 
2780   return makeArrayRef(Parts.data(), NumParts);
2781 }
2782 
2783 const TargetRegisterClass*
2784 SIRegisterInfo::getRegClassForReg(const MachineRegisterInfo &MRI,
2785                                   Register Reg) const {
2786   return Reg.isVirtual() ? MRI.getRegClass(Reg) : getPhysRegClass(Reg);
2787 }
2788 
2789 bool SIRegisterInfo::isVGPR(const MachineRegisterInfo &MRI,
2790                             Register Reg) const {
2791   const TargetRegisterClass *RC = getRegClassForReg(MRI, Reg);
2792   // Registers without classes are unaddressable, SGPR-like registers.
2793   return RC && isVGPRClass(RC);
2794 }
2795 
2796 bool SIRegisterInfo::isAGPR(const MachineRegisterInfo &MRI,
2797                             Register Reg) const {
2798   const TargetRegisterClass *RC = getRegClassForReg(MRI, Reg);
2799 
2800   // Registers without classes are unaddressable, SGPR-like registers.
2801   return RC && isAGPRClass(RC);
2802 }
2803 
2804 bool SIRegisterInfo::shouldCoalesce(MachineInstr *MI,
2805                                     const TargetRegisterClass *SrcRC,
2806                                     unsigned SubReg,
2807                                     const TargetRegisterClass *DstRC,
2808                                     unsigned DstSubReg,
2809                                     const TargetRegisterClass *NewRC,
2810                                     LiveIntervals &LIS) const {
2811   unsigned SrcSize = getRegSizeInBits(*SrcRC);
2812   unsigned DstSize = getRegSizeInBits(*DstRC);
2813   unsigned NewSize = getRegSizeInBits(*NewRC);
2814 
2815   // Do not increase size of registers beyond dword, we would need to allocate
2816   // adjacent registers and constraint regalloc more than needed.
2817 
2818   // Always allow dword coalescing.
2819   if (SrcSize <= 32 || DstSize <= 32)
2820     return true;
2821 
2822   return NewSize <= DstSize || NewSize <= SrcSize;
2823 }
2824 
2825 unsigned SIRegisterInfo::getRegPressureLimit(const TargetRegisterClass *RC,
2826                                              MachineFunction &MF) const {
2827   const SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
2828 
2829   unsigned Occupancy = ST.getOccupancyWithLocalMemSize(MFI->getLDSSize(),
2830                                                        MF.getFunction());
2831   switch (RC->getID()) {
2832   default:
2833     return AMDGPUGenRegisterInfo::getRegPressureLimit(RC, MF);
2834   case AMDGPU::VGPR_32RegClassID:
2835   case AMDGPU::VGPR_LO16RegClassID:
2836   case AMDGPU::VGPR_HI16RegClassID:
2837     return std::min(ST.getMaxNumVGPRs(Occupancy), ST.getMaxNumVGPRs(MF));
2838   case AMDGPU::SGPR_32RegClassID:
2839   case AMDGPU::SGPR_LO16RegClassID:
2840     return std::min(ST.getMaxNumSGPRs(Occupancy, true), ST.getMaxNumSGPRs(MF));
2841   }
2842 }
2843 
2844 unsigned SIRegisterInfo::getRegPressureSetLimit(const MachineFunction &MF,
2845                                                 unsigned Idx) const {
2846   if (Idx == AMDGPU::RegisterPressureSets::VGPR_32 ||
2847       Idx == AMDGPU::RegisterPressureSets::AGPR_32)
2848     return getRegPressureLimit(&AMDGPU::VGPR_32RegClass,
2849                                const_cast<MachineFunction &>(MF));
2850 
2851   if (Idx == AMDGPU::RegisterPressureSets::SReg_32)
2852     return getRegPressureLimit(&AMDGPU::SGPR_32RegClass,
2853                                const_cast<MachineFunction &>(MF));
2854 
2855   llvm_unreachable("Unexpected register pressure set!");
2856 }
2857 
2858 const int *SIRegisterInfo::getRegUnitPressureSets(unsigned RegUnit) const {
2859   static const int Empty[] = { -1 };
2860 
2861   if (RegPressureIgnoredUnits[RegUnit])
2862     return Empty;
2863 
2864   return AMDGPUGenRegisterInfo::getRegUnitPressureSets(RegUnit);
2865 }
2866 
2867 MCRegister SIRegisterInfo::getReturnAddressReg(const MachineFunction &MF) const {
2868   // Not a callee saved register.
2869   return AMDGPU::SGPR30_SGPR31;
2870 }
2871 
2872 const TargetRegisterClass *
2873 SIRegisterInfo::getRegClassForSizeOnBank(unsigned Size,
2874                                          const RegisterBank &RB,
2875                                          const MachineRegisterInfo &MRI) const {
2876   switch (RB.getID()) {
2877   case AMDGPU::VGPRRegBankID:
2878     return getVGPRClassForBitWidth(std::max(32u, Size));
2879   case AMDGPU::VCCRegBankID:
2880     assert(Size == 1);
2881     return isWave32 ? &AMDGPU::SReg_32_XM0_XEXECRegClass
2882                     : &AMDGPU::SReg_64_XEXECRegClass;
2883   case AMDGPU::SGPRRegBankID:
2884     return getSGPRClassForBitWidth(std::max(32u, Size));
2885   case AMDGPU::AGPRRegBankID:
2886     return getAGPRClassForBitWidth(std::max(32u, Size));
2887   default:
2888     llvm_unreachable("unknown register bank");
2889   }
2890 }
2891 
2892 const TargetRegisterClass *
2893 SIRegisterInfo::getConstrainedRegClassForOperand(const MachineOperand &MO,
2894                                          const MachineRegisterInfo &MRI) const {
2895   const RegClassOrRegBank &RCOrRB = MRI.getRegClassOrRegBank(MO.getReg());
2896   if (const RegisterBank *RB = RCOrRB.dyn_cast<const RegisterBank*>())
2897     return getRegClassForTypeOnBank(MRI.getType(MO.getReg()), *RB, MRI);
2898 
2899   if (const auto *RC = RCOrRB.dyn_cast<const TargetRegisterClass *>())
2900     return getAllocatableClass(RC);
2901 
2902   return nullptr;
2903 }
2904 
2905 MCRegister SIRegisterInfo::getVCC() const {
2906   return isWave32 ? AMDGPU::VCC_LO : AMDGPU::VCC;
2907 }
2908 
2909 const TargetRegisterClass *SIRegisterInfo::getVGPR64Class() const {
2910   // VGPR tuples have an alignment requirement on gfx90a variants.
2911   return ST.needsAlignedVGPRs() ? &AMDGPU::VReg_64_Align2RegClass
2912                                 : &AMDGPU::VReg_64RegClass;
2913 }
2914 
2915 const TargetRegisterClass *
2916 SIRegisterInfo::getRegClass(unsigned RCID) const {
2917   switch ((int)RCID) {
2918   case AMDGPU::SReg_1RegClassID:
2919     return getBoolRC();
2920   case AMDGPU::SReg_1_XEXECRegClassID:
2921     return isWave32 ? &AMDGPU::SReg_32_XM0_XEXECRegClass
2922       : &AMDGPU::SReg_64_XEXECRegClass;
2923   case -1:
2924     return nullptr;
2925   default:
2926     return AMDGPUGenRegisterInfo::getRegClass(RCID);
2927   }
2928 }
2929 
2930 // Find reaching register definition
2931 MachineInstr *SIRegisterInfo::findReachingDef(Register Reg, unsigned SubReg,
2932                                               MachineInstr &Use,
2933                                               MachineRegisterInfo &MRI,
2934                                               LiveIntervals *LIS) const {
2935   auto &MDT = LIS->getAnalysis<MachineDominatorTree>();
2936   SlotIndex UseIdx = LIS->getInstructionIndex(Use);
2937   SlotIndex DefIdx;
2938 
2939   if (Reg.isVirtual()) {
2940     if (!LIS->hasInterval(Reg))
2941       return nullptr;
2942     LiveInterval &LI = LIS->getInterval(Reg);
2943     LaneBitmask SubLanes = SubReg ? getSubRegIndexLaneMask(SubReg)
2944                                   : MRI.getMaxLaneMaskForVReg(Reg);
2945     VNInfo *V = nullptr;
2946     if (LI.hasSubRanges()) {
2947       for (auto &S : LI.subranges()) {
2948         if ((S.LaneMask & SubLanes) == SubLanes) {
2949           V = S.getVNInfoAt(UseIdx);
2950           break;
2951         }
2952       }
2953     } else {
2954       V = LI.getVNInfoAt(UseIdx);
2955     }
2956     if (!V)
2957       return nullptr;
2958     DefIdx = V->def;
2959   } else {
2960     // Find last def.
2961     for (MCRegUnitIterator Units(Reg.asMCReg(), this); Units.isValid();
2962          ++Units) {
2963       LiveRange &LR = LIS->getRegUnit(*Units);
2964       if (VNInfo *V = LR.getVNInfoAt(UseIdx)) {
2965         if (!DefIdx.isValid() ||
2966             MDT.dominates(LIS->getInstructionFromIndex(DefIdx),
2967                           LIS->getInstructionFromIndex(V->def)))
2968           DefIdx = V->def;
2969       } else {
2970         return nullptr;
2971       }
2972     }
2973   }
2974 
2975   MachineInstr *Def = LIS->getInstructionFromIndex(DefIdx);
2976 
2977   if (!Def || !MDT.dominates(Def, &Use))
2978     return nullptr;
2979 
2980   assert(Def->modifiesRegister(Reg, this));
2981 
2982   return Def;
2983 }
2984 
2985 MCPhysReg SIRegisterInfo::get32BitRegister(MCPhysReg Reg) const {
2986   assert(getRegSizeInBits(*getPhysRegClass(Reg)) <= 32);
2987 
2988   for (const TargetRegisterClass &RC : { AMDGPU::VGPR_32RegClass,
2989                                          AMDGPU::SReg_32RegClass,
2990                                          AMDGPU::AGPR_32RegClass } ) {
2991     if (MCPhysReg Super = getMatchingSuperReg(Reg, AMDGPU::lo16, &RC))
2992       return Super;
2993   }
2994   if (MCPhysReg Super = getMatchingSuperReg(Reg, AMDGPU::hi16,
2995                                             &AMDGPU::VGPR_32RegClass)) {
2996       return Super;
2997   }
2998 
2999   return AMDGPU::NoRegister;
3000 }
3001 
3002 bool SIRegisterInfo::isProperlyAlignedRC(const TargetRegisterClass &RC) const {
3003   if (!ST.needsAlignedVGPRs())
3004     return true;
3005 
3006   if (isVGPRClass(&RC))
3007     return RC.hasSuperClassEq(getVGPRClassForBitWidth(getRegSizeInBits(RC)));
3008   if (isAGPRClass(&RC))
3009     return RC.hasSuperClassEq(getAGPRClassForBitWidth(getRegSizeInBits(RC)));
3010   if (isVectorSuperClass(&RC))
3011     return RC.hasSuperClassEq(
3012         getVectorSuperClassForBitWidth(getRegSizeInBits(RC)));
3013 
3014   return true;
3015 }
3016 
3017 bool SIRegisterInfo::isConstantPhysReg(MCRegister PhysReg) const {
3018   switch (PhysReg) {
3019   case AMDGPU::SGPR_NULL:
3020   case AMDGPU::SRC_SHARED_BASE:
3021   case AMDGPU::SRC_PRIVATE_BASE:
3022   case AMDGPU::SRC_SHARED_LIMIT:
3023   case AMDGPU::SRC_PRIVATE_LIMIT:
3024     return true;
3025   default:
3026     return false;
3027   }
3028 }
3029 
3030 ArrayRef<MCPhysReg>
3031 SIRegisterInfo::getAllSGPR128(const MachineFunction &MF) const {
3032   return makeArrayRef(AMDGPU::SGPR_128RegClass.begin(),
3033                       ST.getMaxNumSGPRs(MF) / 4);
3034 }
3035 
3036 ArrayRef<MCPhysReg>
3037 SIRegisterInfo::getAllSGPR64(const MachineFunction &MF) const {
3038   return makeArrayRef(AMDGPU::SGPR_64RegClass.begin(),
3039                       ST.getMaxNumSGPRs(MF) / 2);
3040 }
3041 
3042 ArrayRef<MCPhysReg>
3043 SIRegisterInfo::getAllSGPR32(const MachineFunction &MF) const {
3044   return makeArrayRef(AMDGPU::SGPR_32RegClass.begin(), ST.getMaxNumSGPRs(MF));
3045 }
3046