1 //===- SIInstrInfo.cpp - SI Instruction 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 TargetInstrInfo.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "SIInstrInfo.h"
15 #include "AMDGPU.h"
16 #include "AMDGPUSubtarget.h"
17 #include "GCNHazardRecognizer.h"
18 #include "SIDefines.h"
19 #include "SIMachineFunctionInfo.h"
20 #include "SIRegisterInfo.h"
21 #include "MCTargetDesc/AMDGPUMCTargetDesc.h"
22 #include "Utils/AMDGPUBaseInfo.h"
23 #include "llvm/ADT/APInt.h"
24 #include "llvm/ADT/ArrayRef.h"
25 #include "llvm/ADT/SmallVector.h"
26 #include "llvm/ADT/StringRef.h"
27 #include "llvm/ADT/iterator_range.h"
28 #include "llvm/Analysis/AliasAnalysis.h"
29 #include "llvm/Analysis/MemoryLocation.h"
30 #include "llvm/Analysis/ValueTracking.h"
31 #include "llvm/CodeGen/MachineBasicBlock.h"
32 #include "llvm/CodeGen/MachineDominators.h"
33 #include "llvm/CodeGen/MachineFrameInfo.h"
34 #include "llvm/CodeGen/MachineFunction.h"
35 #include "llvm/CodeGen/MachineInstr.h"
36 #include "llvm/CodeGen/MachineInstrBuilder.h"
37 #include "llvm/CodeGen/MachineInstrBundle.h"
38 #include "llvm/CodeGen/MachineMemOperand.h"
39 #include "llvm/CodeGen/MachineOperand.h"
40 #include "llvm/CodeGen/MachineRegisterInfo.h"
41 #include "llvm/CodeGen/RegisterScavenging.h"
42 #include "llvm/CodeGen/ScheduleDAG.h"
43 #include "llvm/CodeGen/SelectionDAGNodes.h"
44 #include "llvm/CodeGen/TargetOpcodes.h"
45 #include "llvm/CodeGen/TargetRegisterInfo.h"
46 #include "llvm/IR/DebugLoc.h"
47 #include "llvm/IR/DiagnosticInfo.h"
48 #include "llvm/IR/Function.h"
49 #include "llvm/IR/InlineAsm.h"
50 #include "llvm/IR/LLVMContext.h"
51 #include "llvm/MC/MCInstrDesc.h"
52 #include "llvm/Support/Casting.h"
53 #include "llvm/Support/CommandLine.h"
54 #include "llvm/Support/Compiler.h"
55 #include "llvm/Support/ErrorHandling.h"
56 #include "llvm/Support/MachineValueType.h"
57 #include "llvm/Support/MathExtras.h"
58 #include "llvm/Target/TargetMachine.h"
59 #include <cassert>
60 #include <cstdint>
61 #include <iterator>
62 #include <utility>
63 
64 using namespace llvm;
65 
66 #define GET_INSTRINFO_CTOR_DTOR
67 #include "AMDGPUGenInstrInfo.inc"
68 
69 namespace llvm {
70 namespace AMDGPU {
71 #define GET_D16ImageDimIntrinsics_IMPL
72 #define GET_ImageDimIntrinsicTable_IMPL
73 #define GET_RsrcIntrinsics_IMPL
74 #include "AMDGPUGenSearchableTables.inc"
75 }
76 }
77 
78 
79 // Must be at least 4 to be able to branch over minimum unconditional branch
80 // code. This is only for making it possible to write reasonably small tests for
81 // long branches.
82 static cl::opt<unsigned>
83 BranchOffsetBits("amdgpu-s-branch-bits", cl::ReallyHidden, cl::init(16),
84                  cl::desc("Restrict range of branch instructions (DEBUG)"));
85 
SIInstrInfo(const GCNSubtarget & ST)86 SIInstrInfo::SIInstrInfo(const GCNSubtarget &ST)
87   : AMDGPUGenInstrInfo(AMDGPU::ADJCALLSTACKUP, AMDGPU::ADJCALLSTACKDOWN),
88     RI(ST), ST(ST) {
89   SchedModel.init(&ST);
90 }
91 
92 //===----------------------------------------------------------------------===//
93 // TargetInstrInfo callbacks
94 //===----------------------------------------------------------------------===//
95 
getNumOperandsNoGlue(SDNode * Node)96 static unsigned getNumOperandsNoGlue(SDNode *Node) {
97   unsigned N = Node->getNumOperands();
98   while (N && Node->getOperand(N - 1).getValueType() == MVT::Glue)
99     --N;
100   return N;
101 }
102 
103 /// Returns true if both nodes have the same value for the given
104 ///        operand \p Op, or if both nodes do not have this operand.
nodesHaveSameOperandValue(SDNode * N0,SDNode * N1,unsigned OpName)105 static bool nodesHaveSameOperandValue(SDNode *N0, SDNode* N1, unsigned OpName) {
106   unsigned Opc0 = N0->getMachineOpcode();
107   unsigned Opc1 = N1->getMachineOpcode();
108 
109   int Op0Idx = AMDGPU::getNamedOperandIdx(Opc0, OpName);
110   int Op1Idx = AMDGPU::getNamedOperandIdx(Opc1, OpName);
111 
112   if (Op0Idx == -1 && Op1Idx == -1)
113     return true;
114 
115 
116   if ((Op0Idx == -1 && Op1Idx != -1) ||
117       (Op1Idx == -1 && Op0Idx != -1))
118     return false;
119 
120   // getNamedOperandIdx returns the index for the MachineInstr's operands,
121   // which includes the result as the first operand. We are indexing into the
122   // MachineSDNode's operands, so we need to skip the result operand to get
123   // the real index.
124   --Op0Idx;
125   --Op1Idx;
126 
127   return N0->getOperand(Op0Idx) == N1->getOperand(Op1Idx);
128 }
129 
isReallyTriviallyReMaterializable(const MachineInstr & MI,AliasAnalysis * AA) const130 bool SIInstrInfo::isReallyTriviallyReMaterializable(const MachineInstr &MI,
131                                                     AliasAnalysis *AA) const {
132   // TODO: The generic check fails for VALU instructions that should be
133   // rematerializable due to implicit reads of exec. We really want all of the
134   // generic logic for this except for this.
135   switch (MI.getOpcode()) {
136   case AMDGPU::V_MOV_B32_e32:
137   case AMDGPU::V_MOV_B32_e64:
138   case AMDGPU::V_MOV_B64_PSEUDO:
139     // No implicit operands.
140     return MI.getNumOperands() == MI.getDesc().getNumOperands();
141   default:
142     return false;
143   }
144 }
145 
areLoadsFromSameBasePtr(SDNode * Load0,SDNode * Load1,int64_t & Offset0,int64_t & Offset1) const146 bool SIInstrInfo::areLoadsFromSameBasePtr(SDNode *Load0, SDNode *Load1,
147                                           int64_t &Offset0,
148                                           int64_t &Offset1) const {
149   if (!Load0->isMachineOpcode() || !Load1->isMachineOpcode())
150     return false;
151 
152   unsigned Opc0 = Load0->getMachineOpcode();
153   unsigned Opc1 = Load1->getMachineOpcode();
154 
155   // Make sure both are actually loads.
156   if (!get(Opc0).mayLoad() || !get(Opc1).mayLoad())
157     return false;
158 
159   if (isDS(Opc0) && isDS(Opc1)) {
160 
161     // FIXME: Handle this case:
162     if (getNumOperandsNoGlue(Load0) != getNumOperandsNoGlue(Load1))
163       return false;
164 
165     // Check base reg.
166     if (Load0->getOperand(0) != Load1->getOperand(0))
167       return false;
168 
169     // Skip read2 / write2 variants for simplicity.
170     // TODO: We should report true if the used offsets are adjacent (excluded
171     // st64 versions).
172     int Offset0Idx = AMDGPU::getNamedOperandIdx(Opc0, AMDGPU::OpName::offset);
173     int Offset1Idx = AMDGPU::getNamedOperandIdx(Opc1, AMDGPU::OpName::offset);
174     if (Offset0Idx == -1 || Offset1Idx == -1)
175       return false;
176 
177     // XXX - be careful of datalesss loads
178     // getNamedOperandIdx returns the index for MachineInstrs.  Since they
179     // include the output in the operand list, but SDNodes don't, we need to
180     // subtract the index by one.
181     Offset0Idx -= get(Opc0).NumDefs;
182     Offset1Idx -= get(Opc1).NumDefs;
183     Offset0 = cast<ConstantSDNode>(Load0->getOperand(Offset0Idx))->getZExtValue();
184     Offset1 = cast<ConstantSDNode>(Load1->getOperand(Offset1Idx))->getZExtValue();
185     return true;
186   }
187 
188   if (isSMRD(Opc0) && isSMRD(Opc1)) {
189     // Skip time and cache invalidation instructions.
190     if (AMDGPU::getNamedOperandIdx(Opc0, AMDGPU::OpName::sbase) == -1 ||
191         AMDGPU::getNamedOperandIdx(Opc1, AMDGPU::OpName::sbase) == -1)
192       return false;
193 
194     assert(getNumOperandsNoGlue(Load0) == getNumOperandsNoGlue(Load1));
195 
196     // Check base reg.
197     if (Load0->getOperand(0) != Load1->getOperand(0))
198       return false;
199 
200     const ConstantSDNode *Load0Offset =
201         dyn_cast<ConstantSDNode>(Load0->getOperand(1));
202     const ConstantSDNode *Load1Offset =
203         dyn_cast<ConstantSDNode>(Load1->getOperand(1));
204 
205     if (!Load0Offset || !Load1Offset)
206       return false;
207 
208     Offset0 = Load0Offset->getZExtValue();
209     Offset1 = Load1Offset->getZExtValue();
210     return true;
211   }
212 
213   // MUBUF and MTBUF can access the same addresses.
214   if ((isMUBUF(Opc0) || isMTBUF(Opc0)) && (isMUBUF(Opc1) || isMTBUF(Opc1))) {
215 
216     // MUBUF and MTBUF have vaddr at different indices.
217     if (!nodesHaveSameOperandValue(Load0, Load1, AMDGPU::OpName::soffset) ||
218         !nodesHaveSameOperandValue(Load0, Load1, AMDGPU::OpName::vaddr) ||
219         !nodesHaveSameOperandValue(Load0, Load1, AMDGPU::OpName::srsrc))
220       return false;
221 
222     int OffIdx0 = AMDGPU::getNamedOperandIdx(Opc0, AMDGPU::OpName::offset);
223     int OffIdx1 = AMDGPU::getNamedOperandIdx(Opc1, AMDGPU::OpName::offset);
224 
225     if (OffIdx0 == -1 || OffIdx1 == -1)
226       return false;
227 
228     // getNamedOperandIdx returns the index for MachineInstrs.  Since they
229     // include the output in the operand list, but SDNodes don't, we need to
230     // subtract the index by one.
231     OffIdx0 -= get(Opc0).NumDefs;
232     OffIdx1 -= get(Opc1).NumDefs;
233 
234     SDValue Off0 = Load0->getOperand(OffIdx0);
235     SDValue Off1 = Load1->getOperand(OffIdx1);
236 
237     // The offset might be a FrameIndexSDNode.
238     if (!isa<ConstantSDNode>(Off0) || !isa<ConstantSDNode>(Off1))
239       return false;
240 
241     Offset0 = cast<ConstantSDNode>(Off0)->getZExtValue();
242     Offset1 = cast<ConstantSDNode>(Off1)->getZExtValue();
243     return true;
244   }
245 
246   return false;
247 }
248 
isStride64(unsigned Opc)249 static bool isStride64(unsigned Opc) {
250   switch (Opc) {
251   case AMDGPU::DS_READ2ST64_B32:
252   case AMDGPU::DS_READ2ST64_B64:
253   case AMDGPU::DS_WRITE2ST64_B32:
254   case AMDGPU::DS_WRITE2ST64_B64:
255     return true;
256   default:
257     return false;
258   }
259 }
260 
getMemOperandWithOffset(const MachineInstr & LdSt,const MachineOperand * & BaseOp,int64_t & Offset,const TargetRegisterInfo * TRI) const261 bool SIInstrInfo::getMemOperandWithOffset(const MachineInstr &LdSt,
262                                           const MachineOperand *&BaseOp,
263                                           int64_t &Offset,
264                                           const TargetRegisterInfo *TRI) const {
265   if (!LdSt.mayLoadOrStore())
266     return false;
267 
268   unsigned Opc = LdSt.getOpcode();
269 
270   if (isDS(LdSt)) {
271     const MachineOperand *OffsetImm =
272         getNamedOperand(LdSt, AMDGPU::OpName::offset);
273     if (OffsetImm) {
274       // Normal, single offset LDS instruction.
275       BaseOp = getNamedOperand(LdSt, AMDGPU::OpName::addr);
276       // TODO: ds_consume/ds_append use M0 for the base address. Is it safe to
277       // report that here?
278       if (!BaseOp || !BaseOp->isReg())
279         return false;
280 
281       Offset = OffsetImm->getImm();
282 
283       return true;
284     }
285 
286     // The 2 offset instructions use offset0 and offset1 instead. We can treat
287     // these as a load with a single offset if the 2 offsets are consecutive. We
288     // will use this for some partially aligned loads.
289     const MachineOperand *Offset0Imm =
290         getNamedOperand(LdSt, AMDGPU::OpName::offset0);
291     const MachineOperand *Offset1Imm =
292         getNamedOperand(LdSt, AMDGPU::OpName::offset1);
293 
294     uint8_t Offset0 = Offset0Imm->getImm();
295     uint8_t Offset1 = Offset1Imm->getImm();
296 
297     if (Offset1 > Offset0 && Offset1 - Offset0 == 1) {
298       // Each of these offsets is in element sized units, so we need to convert
299       // to bytes of the individual reads.
300 
301       unsigned EltSize;
302       if (LdSt.mayLoad())
303         EltSize = TRI->getRegSizeInBits(*getOpRegClass(LdSt, 0)) / 16;
304       else {
305         assert(LdSt.mayStore());
306         int Data0Idx = AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::data0);
307         EltSize = TRI->getRegSizeInBits(*getOpRegClass(LdSt, Data0Idx)) / 8;
308       }
309 
310       if (isStride64(Opc))
311         EltSize *= 64;
312 
313       BaseOp = getNamedOperand(LdSt, AMDGPU::OpName::addr);
314       if (!BaseOp->isReg())
315         return false;
316 
317       Offset = EltSize * Offset0;
318 
319       return true;
320     }
321 
322     return false;
323   }
324 
325   if (isMUBUF(LdSt) || isMTBUF(LdSt)) {
326     const MachineOperand *SOffset = getNamedOperand(LdSt, AMDGPU::OpName::soffset);
327     if (SOffset && SOffset->isReg()) {
328       // We can only handle this if it's a stack access, as any other resource
329       // would require reporting multiple base registers.
330       const MachineOperand *AddrReg = getNamedOperand(LdSt, AMDGPU::OpName::vaddr);
331       if (AddrReg && !AddrReg->isFI())
332         return false;
333 
334       const MachineOperand *RSrc = getNamedOperand(LdSt, AMDGPU::OpName::srsrc);
335       const SIMachineFunctionInfo *MFI
336         = LdSt.getParent()->getParent()->getInfo<SIMachineFunctionInfo>();
337       if (RSrc->getReg() != MFI->getScratchRSrcReg())
338         return false;
339 
340       const MachineOperand *OffsetImm =
341         getNamedOperand(LdSt, AMDGPU::OpName::offset);
342       BaseOp = SOffset;
343       Offset = OffsetImm->getImm();
344       return true;
345     }
346 
347     const MachineOperand *AddrReg = getNamedOperand(LdSt, AMDGPU::OpName::vaddr);
348     if (!AddrReg)
349       return false;
350 
351     const MachineOperand *OffsetImm =
352         getNamedOperand(LdSt, AMDGPU::OpName::offset);
353     BaseOp = AddrReg;
354     Offset = OffsetImm->getImm();
355     if (SOffset) // soffset can be an inline immediate.
356       Offset += SOffset->getImm();
357 
358     if (!BaseOp->isReg())
359       return false;
360 
361     return true;
362   }
363 
364   if (isSMRD(LdSt)) {
365     const MachineOperand *OffsetImm =
366         getNamedOperand(LdSt, AMDGPU::OpName::offset);
367     if (!OffsetImm)
368       return false;
369 
370     const MachineOperand *SBaseReg = getNamedOperand(LdSt, AMDGPU::OpName::sbase);
371     BaseOp = SBaseReg;
372     Offset = OffsetImm->getImm();
373     if (!BaseOp->isReg())
374       return false;
375 
376     return true;
377   }
378 
379   if (isFLAT(LdSt)) {
380     const MachineOperand *VAddr = getNamedOperand(LdSt, AMDGPU::OpName::vaddr);
381     if (VAddr) {
382       // Can't analyze 2 offsets.
383       if (getNamedOperand(LdSt, AMDGPU::OpName::saddr))
384         return false;
385 
386       BaseOp = VAddr;
387     } else {
388       // scratch instructions have either vaddr or saddr.
389       BaseOp = getNamedOperand(LdSt, AMDGPU::OpName::saddr);
390     }
391 
392     Offset = getNamedOperand(LdSt, AMDGPU::OpName::offset)->getImm();
393     if (!BaseOp->isReg())
394       return false;
395     return true;
396   }
397 
398   return false;
399 }
400 
memOpsHaveSameBasePtr(const MachineInstr & MI1,const MachineOperand & BaseOp1,const MachineInstr & MI2,const MachineOperand & BaseOp2)401 static bool memOpsHaveSameBasePtr(const MachineInstr &MI1,
402                                   const MachineOperand &BaseOp1,
403                                   const MachineInstr &MI2,
404                                   const MachineOperand &BaseOp2) {
405   // Support only base operands with base registers.
406   // Note: this could be extended to support FI operands.
407   if (!BaseOp1.isReg() || !BaseOp2.isReg())
408     return false;
409 
410   if (BaseOp1.isIdenticalTo(BaseOp2))
411     return true;
412 
413   if (!MI1.hasOneMemOperand() || !MI2.hasOneMemOperand())
414     return false;
415 
416   auto MO1 = *MI1.memoperands_begin();
417   auto MO2 = *MI2.memoperands_begin();
418   if (MO1->getAddrSpace() != MO2->getAddrSpace())
419     return false;
420 
421   auto Base1 = MO1->getValue();
422   auto Base2 = MO2->getValue();
423   if (!Base1 || !Base2)
424     return false;
425   const MachineFunction &MF = *MI1.getParent()->getParent();
426   const DataLayout &DL = MF.getFunction().getParent()->getDataLayout();
427   Base1 = GetUnderlyingObject(Base1, DL);
428   Base2 = GetUnderlyingObject(Base2, DL);
429 
430   if (isa<UndefValue>(Base1) || isa<UndefValue>(Base2))
431     return false;
432 
433   return Base1 == Base2;
434 }
435 
shouldClusterMemOps(const MachineOperand & BaseOp1,const MachineOperand & BaseOp2,unsigned NumLoads) const436 bool SIInstrInfo::shouldClusterMemOps(const MachineOperand &BaseOp1,
437                                       const MachineOperand &BaseOp2,
438                                       unsigned NumLoads) const {
439   const MachineInstr &FirstLdSt = *BaseOp1.getParent();
440   const MachineInstr &SecondLdSt = *BaseOp2.getParent();
441 
442   if (!memOpsHaveSameBasePtr(FirstLdSt, BaseOp1, SecondLdSt, BaseOp2))
443     return false;
444 
445   const MachineOperand *FirstDst = nullptr;
446   const MachineOperand *SecondDst = nullptr;
447 
448   if ((isMUBUF(FirstLdSt) && isMUBUF(SecondLdSt)) ||
449       (isMTBUF(FirstLdSt) && isMTBUF(SecondLdSt)) ||
450       (isFLAT(FirstLdSt) && isFLAT(SecondLdSt))) {
451     const unsigned MaxGlobalLoadCluster = 6;
452     if (NumLoads > MaxGlobalLoadCluster)
453       return false;
454 
455     FirstDst = getNamedOperand(FirstLdSt, AMDGPU::OpName::vdata);
456     if (!FirstDst)
457       FirstDst = getNamedOperand(FirstLdSt, AMDGPU::OpName::vdst);
458     SecondDst = getNamedOperand(SecondLdSt, AMDGPU::OpName::vdata);
459     if (!SecondDst)
460       SecondDst = getNamedOperand(SecondLdSt, AMDGPU::OpName::vdst);
461   } else if (isSMRD(FirstLdSt) && isSMRD(SecondLdSt)) {
462     FirstDst = getNamedOperand(FirstLdSt, AMDGPU::OpName::sdst);
463     SecondDst = getNamedOperand(SecondLdSt, AMDGPU::OpName::sdst);
464   } else if (isDS(FirstLdSt) && isDS(SecondLdSt)) {
465     FirstDst = getNamedOperand(FirstLdSt, AMDGPU::OpName::vdst);
466     SecondDst = getNamedOperand(SecondLdSt, AMDGPU::OpName::vdst);
467   }
468 
469   if (!FirstDst || !SecondDst)
470     return false;
471 
472   // Try to limit clustering based on the total number of bytes loaded
473   // rather than the number of instructions.  This is done to help reduce
474   // register pressure.  The method used is somewhat inexact, though,
475   // because it assumes that all loads in the cluster will load the
476   // same number of bytes as FirstLdSt.
477 
478   // The unit of this value is bytes.
479   // FIXME: This needs finer tuning.
480   unsigned LoadClusterThreshold = 16;
481 
482   const MachineRegisterInfo &MRI =
483       FirstLdSt.getParent()->getParent()->getRegInfo();
484 
485   const Register Reg = FirstDst->getReg();
486 
487   const TargetRegisterClass *DstRC = Register::isVirtualRegister(Reg)
488                                          ? MRI.getRegClass(Reg)
489                                          : RI.getPhysRegClass(Reg);
490 
491   return (NumLoads * (RI.getRegSizeInBits(*DstRC) / 8)) <= LoadClusterThreshold;
492 }
493 
494 // FIXME: This behaves strangely. If, for example, you have 32 load + stores,
495 // the first 16 loads will be interleaved with the stores, and the next 16 will
496 // be clustered as expected. It should really split into 2 16 store batches.
497 //
498 // Loads are clustered until this returns false, rather than trying to schedule
499 // groups of stores. This also means we have to deal with saying different
500 // address space loads should be clustered, and ones which might cause bank
501 // conflicts.
502 //
503 // This might be deprecated so it might not be worth that much effort to fix.
shouldScheduleLoadsNear(SDNode * Load0,SDNode * Load1,int64_t Offset0,int64_t Offset1,unsigned NumLoads) const504 bool SIInstrInfo::shouldScheduleLoadsNear(SDNode *Load0, SDNode *Load1,
505                                           int64_t Offset0, int64_t Offset1,
506                                           unsigned NumLoads) const {
507   assert(Offset1 > Offset0 &&
508          "Second offset should be larger than first offset!");
509   // If we have less than 16 loads in a row, and the offsets are within 64
510   // bytes, then schedule together.
511 
512   // A cacheline is 64 bytes (for global memory).
513   return (NumLoads <= 16 && (Offset1 - Offset0) < 64);
514 }
515 
reportIllegalCopy(const SIInstrInfo * TII,MachineBasicBlock & MBB,MachineBasicBlock::iterator MI,const DebugLoc & DL,MCRegister DestReg,MCRegister SrcReg,bool KillSrc)516 static void reportIllegalCopy(const SIInstrInfo *TII, MachineBasicBlock &MBB,
517                               MachineBasicBlock::iterator MI,
518                               const DebugLoc &DL, MCRegister DestReg,
519                               MCRegister SrcReg, bool KillSrc) {
520   MachineFunction *MF = MBB.getParent();
521   DiagnosticInfoUnsupported IllegalCopy(MF->getFunction(),
522                                         "illegal SGPR to VGPR copy",
523                                         DL, DS_Error);
524   LLVMContext &C = MF->getFunction().getContext();
525   C.diagnose(IllegalCopy);
526 
527   BuildMI(MBB, MI, DL, TII->get(AMDGPU::SI_ILLEGAL_COPY), DestReg)
528     .addReg(SrcReg, getKillRegState(KillSrc));
529 }
530 
copyPhysReg(MachineBasicBlock & MBB,MachineBasicBlock::iterator MI,const DebugLoc & DL,MCRegister DestReg,MCRegister SrcReg,bool KillSrc) const531 void SIInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
532                               MachineBasicBlock::iterator MI,
533                               const DebugLoc &DL, MCRegister DestReg,
534                               MCRegister SrcReg, bool KillSrc) const {
535   const TargetRegisterClass *RC = RI.getPhysRegClass(DestReg);
536 
537   if (RC == &AMDGPU::VGPR_32RegClass) {
538     assert(AMDGPU::VGPR_32RegClass.contains(SrcReg) ||
539            AMDGPU::SReg_32RegClass.contains(SrcReg) ||
540            AMDGPU::AGPR_32RegClass.contains(SrcReg));
541     unsigned Opc = AMDGPU::AGPR_32RegClass.contains(SrcReg) ?
542                      AMDGPU::V_ACCVGPR_READ_B32 : AMDGPU::V_MOV_B32_e32;
543     BuildMI(MBB, MI, DL, get(Opc), DestReg)
544       .addReg(SrcReg, getKillRegState(KillSrc));
545     return;
546   }
547 
548   if (RC == &AMDGPU::SReg_32_XM0RegClass ||
549       RC == &AMDGPU::SReg_32RegClass) {
550     if (SrcReg == AMDGPU::SCC) {
551       BuildMI(MBB, MI, DL, get(AMDGPU::S_CSELECT_B32), DestReg)
552           .addImm(1)
553           .addImm(0);
554       return;
555     }
556 
557     if (DestReg == AMDGPU::VCC_LO) {
558       if (AMDGPU::SReg_32RegClass.contains(SrcReg)) {
559         BuildMI(MBB, MI, DL, get(AMDGPU::S_MOV_B32), AMDGPU::VCC_LO)
560           .addReg(SrcReg, getKillRegState(KillSrc));
561       } else {
562         // FIXME: Hack until VReg_1 removed.
563         assert(AMDGPU::VGPR_32RegClass.contains(SrcReg));
564         BuildMI(MBB, MI, DL, get(AMDGPU::V_CMP_NE_U32_e32))
565           .addImm(0)
566           .addReg(SrcReg, getKillRegState(KillSrc));
567       }
568 
569       return;
570     }
571 
572     if (!AMDGPU::SReg_32RegClass.contains(SrcReg)) {
573       reportIllegalCopy(this, MBB, MI, DL, DestReg, SrcReg, KillSrc);
574       return;
575     }
576 
577     BuildMI(MBB, MI, DL, get(AMDGPU::S_MOV_B32), DestReg)
578             .addReg(SrcReg, getKillRegState(KillSrc));
579     return;
580   }
581 
582   if (RC == &AMDGPU::SReg_64RegClass) {
583     if (DestReg == AMDGPU::VCC) {
584       if (AMDGPU::SReg_64RegClass.contains(SrcReg)) {
585         BuildMI(MBB, MI, DL, get(AMDGPU::S_MOV_B64), AMDGPU::VCC)
586           .addReg(SrcReg, getKillRegState(KillSrc));
587       } else {
588         // FIXME: Hack until VReg_1 removed.
589         assert(AMDGPU::VGPR_32RegClass.contains(SrcReg));
590         BuildMI(MBB, MI, DL, get(AMDGPU::V_CMP_NE_U32_e32))
591           .addImm(0)
592           .addReg(SrcReg, getKillRegState(KillSrc));
593       }
594 
595       return;
596     }
597 
598     if (!AMDGPU::SReg_64RegClass.contains(SrcReg)) {
599       reportIllegalCopy(this, MBB, MI, DL, DestReg, SrcReg, KillSrc);
600       return;
601     }
602 
603     BuildMI(MBB, MI, DL, get(AMDGPU::S_MOV_B64), DestReg)
604             .addReg(SrcReg, getKillRegState(KillSrc));
605     return;
606   }
607 
608   if (DestReg == AMDGPU::SCC) {
609     assert(AMDGPU::SReg_32RegClass.contains(SrcReg));
610     BuildMI(MBB, MI, DL, get(AMDGPU::S_CMP_LG_U32))
611       .addReg(SrcReg, getKillRegState(KillSrc))
612       .addImm(0);
613     return;
614   }
615 
616   if (RC == &AMDGPU::AGPR_32RegClass) {
617     assert(AMDGPU::VGPR_32RegClass.contains(SrcReg) ||
618            AMDGPU::SReg_32RegClass.contains(SrcReg) ||
619            AMDGPU::AGPR_32RegClass.contains(SrcReg));
620     if (!AMDGPU::VGPR_32RegClass.contains(SrcReg)) {
621       // First try to find defining accvgpr_write to avoid temporary registers.
622       for (auto Def = MI, E = MBB.begin(); Def != E; ) {
623         --Def;
624         if (!Def->definesRegister(SrcReg, &RI))
625           continue;
626         if (Def->getOpcode() != AMDGPU::V_ACCVGPR_WRITE_B32)
627           break;
628 
629         MachineOperand &DefOp = Def->getOperand(1);
630         assert(DefOp.isReg() || DefOp.isImm());
631 
632         if (DefOp.isReg()) {
633           // Check that register source operand if not clobbered before MI.
634           // Immediate operands are always safe to propagate.
635           bool SafeToPropagate = true;
636           for (auto I = Def; I != MI && SafeToPropagate; ++I)
637             if (I->modifiesRegister(DefOp.getReg(), &RI))
638               SafeToPropagate = false;
639 
640           if (!SafeToPropagate)
641             break;
642 
643           DefOp.setIsKill(false);
644         }
645 
646         BuildMI(MBB, MI, DL, get(AMDGPU::V_ACCVGPR_WRITE_B32), DestReg)
647           .add(DefOp);
648         return;
649       }
650 
651       RegScavenger RS;
652       RS.enterBasicBlock(MBB);
653       RS.forward(MI);
654 
655       // Ideally we want to have three registers for a long reg_sequence copy
656       // to hide 2 waitstates between v_mov_b32 and accvgpr_write.
657       unsigned MaxVGPRs = RI.getRegPressureLimit(&AMDGPU::VGPR_32RegClass,
658                                                  *MBB.getParent());
659 
660       // Registers in the sequence are allocated contiguously so we can just
661       // use register number to pick one of three round-robin temps.
662       unsigned RegNo = DestReg % 3;
663       unsigned Tmp = RS.scavengeRegister(&AMDGPU::VGPR_32RegClass, 0);
664       if (!Tmp)
665         report_fatal_error("Cannot scavenge VGPR to copy to AGPR");
666       RS.setRegUsed(Tmp);
667       // Only loop through if there are any free registers left, otherwise
668       // scavenger may report a fatal error without emergency spill slot
669       // or spill with the slot.
670       while (RegNo-- && RS.FindUnusedReg(&AMDGPU::VGPR_32RegClass)) {
671         unsigned Tmp2 = RS.scavengeRegister(&AMDGPU::VGPR_32RegClass, 0);
672         if (!Tmp2 || RI.getHWRegIndex(Tmp2) >= MaxVGPRs)
673           break;
674         Tmp = Tmp2;
675         RS.setRegUsed(Tmp);
676       }
677       copyPhysReg(MBB, MI, DL, Tmp, SrcReg, KillSrc);
678       BuildMI(MBB, MI, DL, get(AMDGPU::V_ACCVGPR_WRITE_B32), DestReg)
679         .addReg(Tmp, RegState::Kill);
680       return;
681     }
682 
683     BuildMI(MBB, MI, DL, get(AMDGPU::V_ACCVGPR_WRITE_B32), DestReg)
684       .addReg(SrcReg, getKillRegState(KillSrc));
685     return;
686   }
687 
688   unsigned EltSize = 4;
689   unsigned Opcode = AMDGPU::V_MOV_B32_e32;
690   if (RI.isSGPRClass(RC)) {
691     // TODO: Copy vec3/vec5 with s_mov_b64s then final s_mov_b32.
692     if (!(RI.getRegSizeInBits(*RC) % 64)) {
693       Opcode =  AMDGPU::S_MOV_B64;
694       EltSize = 8;
695     } else {
696       Opcode = AMDGPU::S_MOV_B32;
697       EltSize = 4;
698     }
699 
700     if (!RI.isSGPRClass(RI.getPhysRegClass(SrcReg))) {
701       reportIllegalCopy(this, MBB, MI, DL, DestReg, SrcReg, KillSrc);
702       return;
703     }
704   } else if (RI.hasAGPRs(RC)) {
705     Opcode = RI.hasVGPRs(RI.getPhysRegClass(SrcReg)) ?
706       AMDGPU::V_ACCVGPR_WRITE_B32 : AMDGPU::COPY;
707   } else if (RI.hasVGPRs(RC) && RI.hasAGPRs(RI.getPhysRegClass(SrcReg))) {
708     Opcode = AMDGPU::V_ACCVGPR_READ_B32;
709   }
710 
711   ArrayRef<int16_t> SubIndices = RI.getRegSplitParts(RC, EltSize);
712   bool Forward = RI.getHWRegIndex(DestReg) <= RI.getHWRegIndex(SrcReg);
713 
714   for (unsigned Idx = 0; Idx < SubIndices.size(); ++Idx) {
715     unsigned SubIdx;
716     if (Forward)
717       SubIdx = SubIndices[Idx];
718     else
719       SubIdx = SubIndices[SubIndices.size() - Idx - 1];
720 
721     if (Opcode == TargetOpcode::COPY) {
722       copyPhysReg(MBB, MI, DL, RI.getSubReg(DestReg, SubIdx),
723                   RI.getSubReg(SrcReg, SubIdx), KillSrc);
724       continue;
725     }
726 
727     MachineInstrBuilder Builder = BuildMI(MBB, MI, DL,
728       get(Opcode), RI.getSubReg(DestReg, SubIdx));
729 
730     Builder.addReg(RI.getSubReg(SrcReg, SubIdx));
731 
732     if (Idx == 0)
733       Builder.addReg(DestReg, RegState::Define | RegState::Implicit);
734 
735     bool UseKill = KillSrc && Idx == SubIndices.size() - 1;
736     Builder.addReg(SrcReg, getKillRegState(UseKill) | RegState::Implicit);
737   }
738 }
739 
commuteOpcode(unsigned Opcode) const740 int SIInstrInfo::commuteOpcode(unsigned Opcode) const {
741   int NewOpc;
742 
743   // Try to map original to commuted opcode
744   NewOpc = AMDGPU::getCommuteRev(Opcode);
745   if (NewOpc != -1)
746     // Check if the commuted (REV) opcode exists on the target.
747     return pseudoToMCOpcode(NewOpc) != -1 ? NewOpc : -1;
748 
749   // Try to map commuted to original opcode
750   NewOpc = AMDGPU::getCommuteOrig(Opcode);
751   if (NewOpc != -1)
752     // Check if the original (non-REV) opcode exists on the target.
753     return pseudoToMCOpcode(NewOpc) != -1 ? NewOpc : -1;
754 
755   return Opcode;
756 }
757 
materializeImmediate(MachineBasicBlock & MBB,MachineBasicBlock::iterator MI,const DebugLoc & DL,unsigned DestReg,int64_t Value) const758 void SIInstrInfo::materializeImmediate(MachineBasicBlock &MBB,
759                                        MachineBasicBlock::iterator MI,
760                                        const DebugLoc &DL, unsigned DestReg,
761                                        int64_t Value) const {
762   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
763   const TargetRegisterClass *RegClass = MRI.getRegClass(DestReg);
764   if (RegClass == &AMDGPU::SReg_32RegClass ||
765       RegClass == &AMDGPU::SGPR_32RegClass ||
766       RegClass == &AMDGPU::SReg_32_XM0RegClass ||
767       RegClass == &AMDGPU::SReg_32_XM0_XEXECRegClass) {
768     BuildMI(MBB, MI, DL, get(AMDGPU::S_MOV_B32), DestReg)
769       .addImm(Value);
770     return;
771   }
772 
773   if (RegClass == &AMDGPU::SReg_64RegClass ||
774       RegClass == &AMDGPU::SGPR_64RegClass ||
775       RegClass == &AMDGPU::SReg_64_XEXECRegClass) {
776     BuildMI(MBB, MI, DL, get(AMDGPU::S_MOV_B64), DestReg)
777       .addImm(Value);
778     return;
779   }
780 
781   if (RegClass == &AMDGPU::VGPR_32RegClass) {
782     BuildMI(MBB, MI, DL, get(AMDGPU::V_MOV_B32_e32), DestReg)
783       .addImm(Value);
784     return;
785   }
786   if (RegClass == &AMDGPU::VReg_64RegClass) {
787     BuildMI(MBB, MI, DL, get(AMDGPU::V_MOV_B64_PSEUDO), DestReg)
788       .addImm(Value);
789     return;
790   }
791 
792   unsigned EltSize = 4;
793   unsigned Opcode = AMDGPU::V_MOV_B32_e32;
794   if (RI.isSGPRClass(RegClass)) {
795     if (RI.getRegSizeInBits(*RegClass) > 32) {
796       Opcode =  AMDGPU::S_MOV_B64;
797       EltSize = 8;
798     } else {
799       Opcode = AMDGPU::S_MOV_B32;
800       EltSize = 4;
801     }
802   }
803 
804   ArrayRef<int16_t> SubIndices = RI.getRegSplitParts(RegClass, EltSize);
805   for (unsigned Idx = 0; Idx < SubIndices.size(); ++Idx) {
806     int64_t IdxValue = Idx == 0 ? Value : 0;
807 
808     MachineInstrBuilder Builder = BuildMI(MBB, MI, DL,
809       get(Opcode), RI.getSubReg(DestReg, Idx));
810     Builder.addImm(IdxValue);
811   }
812 }
813 
814 const TargetRegisterClass *
getPreferredSelectRegClass(unsigned Size) const815 SIInstrInfo::getPreferredSelectRegClass(unsigned Size) const {
816   return &AMDGPU::VGPR_32RegClass;
817 }
818 
insertVectorSelect(MachineBasicBlock & MBB,MachineBasicBlock::iterator I,const DebugLoc & DL,unsigned DstReg,ArrayRef<MachineOperand> Cond,unsigned TrueReg,unsigned FalseReg) const819 void SIInstrInfo::insertVectorSelect(MachineBasicBlock &MBB,
820                                      MachineBasicBlock::iterator I,
821                                      const DebugLoc &DL, unsigned DstReg,
822                                      ArrayRef<MachineOperand> Cond,
823                                      unsigned TrueReg,
824                                      unsigned FalseReg) const {
825   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
826   MachineFunction *MF = MBB.getParent();
827   const GCNSubtarget &ST = MF->getSubtarget<GCNSubtarget>();
828   const TargetRegisterClass *BoolXExecRC =
829     RI.getRegClass(AMDGPU::SReg_1_XEXECRegClassID);
830   assert(MRI.getRegClass(DstReg) == &AMDGPU::VGPR_32RegClass &&
831          "Not a VGPR32 reg");
832 
833   if (Cond.size() == 1) {
834     Register SReg = MRI.createVirtualRegister(BoolXExecRC);
835     BuildMI(MBB, I, DL, get(AMDGPU::COPY), SReg)
836       .add(Cond[0]);
837     BuildMI(MBB, I, DL, get(AMDGPU::V_CNDMASK_B32_e64), DstReg)
838       .addImm(0)
839       .addReg(FalseReg)
840       .addImm(0)
841       .addReg(TrueReg)
842       .addReg(SReg);
843   } else if (Cond.size() == 2) {
844     assert(Cond[0].isImm() && "Cond[0] is not an immediate");
845     switch (Cond[0].getImm()) {
846     case SIInstrInfo::SCC_TRUE: {
847       Register SReg = MRI.createVirtualRegister(BoolXExecRC);
848       BuildMI(MBB, I, DL, get(ST.isWave32() ? AMDGPU::S_CSELECT_B32
849                                             : AMDGPU::S_CSELECT_B64), SReg)
850         .addImm(1)
851         .addImm(0);
852       BuildMI(MBB, I, DL, get(AMDGPU::V_CNDMASK_B32_e64), DstReg)
853         .addImm(0)
854         .addReg(FalseReg)
855         .addImm(0)
856         .addReg(TrueReg)
857         .addReg(SReg);
858       break;
859     }
860     case SIInstrInfo::SCC_FALSE: {
861       Register SReg = MRI.createVirtualRegister(BoolXExecRC);
862       BuildMI(MBB, I, DL, get(ST.isWave32() ? AMDGPU::S_CSELECT_B32
863                                             : AMDGPU::S_CSELECT_B64), SReg)
864         .addImm(0)
865         .addImm(1);
866       BuildMI(MBB, I, DL, get(AMDGPU::V_CNDMASK_B32_e64), DstReg)
867         .addImm(0)
868         .addReg(FalseReg)
869         .addImm(0)
870         .addReg(TrueReg)
871         .addReg(SReg);
872       break;
873     }
874     case SIInstrInfo::VCCNZ: {
875       MachineOperand RegOp = Cond[1];
876       RegOp.setImplicit(false);
877       Register SReg = MRI.createVirtualRegister(BoolXExecRC);
878       BuildMI(MBB, I, DL, get(AMDGPU::COPY), SReg)
879         .add(RegOp);
880       BuildMI(MBB, I, DL, get(AMDGPU::V_CNDMASK_B32_e64), DstReg)
881           .addImm(0)
882           .addReg(FalseReg)
883           .addImm(0)
884           .addReg(TrueReg)
885           .addReg(SReg);
886       break;
887     }
888     case SIInstrInfo::VCCZ: {
889       MachineOperand RegOp = Cond[1];
890       RegOp.setImplicit(false);
891       Register SReg = MRI.createVirtualRegister(BoolXExecRC);
892       BuildMI(MBB, I, DL, get(AMDGPU::COPY), SReg)
893         .add(RegOp);
894       BuildMI(MBB, I, DL, get(AMDGPU::V_CNDMASK_B32_e64), DstReg)
895           .addImm(0)
896           .addReg(TrueReg)
897           .addImm(0)
898           .addReg(FalseReg)
899           .addReg(SReg);
900       break;
901     }
902     case SIInstrInfo::EXECNZ: {
903       Register SReg = MRI.createVirtualRegister(BoolXExecRC);
904       Register SReg2 = MRI.createVirtualRegister(RI.getBoolRC());
905       BuildMI(MBB, I, DL, get(ST.isWave32() ? AMDGPU::S_OR_SAVEEXEC_B32
906                                             : AMDGPU::S_OR_SAVEEXEC_B64), SReg2)
907         .addImm(0);
908       BuildMI(MBB, I, DL, get(ST.isWave32() ? AMDGPU::S_CSELECT_B32
909                                             : AMDGPU::S_CSELECT_B64), SReg)
910         .addImm(1)
911         .addImm(0);
912       BuildMI(MBB, I, DL, get(AMDGPU::V_CNDMASK_B32_e64), DstReg)
913         .addImm(0)
914         .addReg(FalseReg)
915         .addImm(0)
916         .addReg(TrueReg)
917         .addReg(SReg);
918       break;
919     }
920     case SIInstrInfo::EXECZ: {
921       Register SReg = MRI.createVirtualRegister(BoolXExecRC);
922       Register SReg2 = MRI.createVirtualRegister(RI.getBoolRC());
923       BuildMI(MBB, I, DL, get(ST.isWave32() ? AMDGPU::S_OR_SAVEEXEC_B32
924                                             : AMDGPU::S_OR_SAVEEXEC_B64), SReg2)
925         .addImm(0);
926       BuildMI(MBB, I, DL, get(ST.isWave32() ? AMDGPU::S_CSELECT_B32
927                                             : AMDGPU::S_CSELECT_B64), SReg)
928         .addImm(0)
929         .addImm(1);
930       BuildMI(MBB, I, DL, get(AMDGPU::V_CNDMASK_B32_e64), DstReg)
931         .addImm(0)
932         .addReg(FalseReg)
933         .addImm(0)
934         .addReg(TrueReg)
935         .addReg(SReg);
936       llvm_unreachable("Unhandled branch predicate EXECZ");
937       break;
938     }
939     default:
940       llvm_unreachable("invalid branch predicate");
941     }
942   } else {
943     llvm_unreachable("Can only handle Cond size 1 or 2");
944   }
945 }
946 
insertEQ(MachineBasicBlock * MBB,MachineBasicBlock::iterator I,const DebugLoc & DL,unsigned SrcReg,int Value) const947 unsigned SIInstrInfo::insertEQ(MachineBasicBlock *MBB,
948                                MachineBasicBlock::iterator I,
949                                const DebugLoc &DL,
950                                unsigned SrcReg, int Value) const {
951   MachineRegisterInfo &MRI = MBB->getParent()->getRegInfo();
952   Register Reg = MRI.createVirtualRegister(RI.getBoolRC());
953   BuildMI(*MBB, I, DL, get(AMDGPU::V_CMP_EQ_I32_e64), Reg)
954     .addImm(Value)
955     .addReg(SrcReg);
956 
957   return Reg;
958 }
959 
insertNE(MachineBasicBlock * MBB,MachineBasicBlock::iterator I,const DebugLoc & DL,unsigned SrcReg,int Value) const960 unsigned SIInstrInfo::insertNE(MachineBasicBlock *MBB,
961                                MachineBasicBlock::iterator I,
962                                const DebugLoc &DL,
963                                unsigned SrcReg, int Value) const {
964   MachineRegisterInfo &MRI = MBB->getParent()->getRegInfo();
965   Register Reg = MRI.createVirtualRegister(RI.getBoolRC());
966   BuildMI(*MBB, I, DL, get(AMDGPU::V_CMP_NE_I32_e64), Reg)
967     .addImm(Value)
968     .addReg(SrcReg);
969 
970   return Reg;
971 }
972 
getMovOpcode(const TargetRegisterClass * DstRC) const973 unsigned SIInstrInfo::getMovOpcode(const TargetRegisterClass *DstRC) const {
974 
975   if (RI.hasAGPRs(DstRC))
976     return AMDGPU::COPY;
977   if (RI.getRegSizeInBits(*DstRC) == 32) {
978     return RI.isSGPRClass(DstRC) ? AMDGPU::S_MOV_B32 : AMDGPU::V_MOV_B32_e32;
979   } else if (RI.getRegSizeInBits(*DstRC) == 64 && RI.isSGPRClass(DstRC)) {
980     return AMDGPU::S_MOV_B64;
981   } else if (RI.getRegSizeInBits(*DstRC) == 64 && !RI.isSGPRClass(DstRC)) {
982     return  AMDGPU::V_MOV_B64_PSEUDO;
983   }
984   return AMDGPU::COPY;
985 }
986 
getSGPRSpillSaveOpcode(unsigned Size)987 static unsigned getSGPRSpillSaveOpcode(unsigned Size) {
988   switch (Size) {
989   case 4:
990     return AMDGPU::SI_SPILL_S32_SAVE;
991   case 8:
992     return AMDGPU::SI_SPILL_S64_SAVE;
993   case 12:
994     return AMDGPU::SI_SPILL_S96_SAVE;
995   case 16:
996     return AMDGPU::SI_SPILL_S128_SAVE;
997   case 20:
998     return AMDGPU::SI_SPILL_S160_SAVE;
999   case 32:
1000     return AMDGPU::SI_SPILL_S256_SAVE;
1001   case 64:
1002     return AMDGPU::SI_SPILL_S512_SAVE;
1003   case 128:
1004     return AMDGPU::SI_SPILL_S1024_SAVE;
1005   default:
1006     llvm_unreachable("unknown register size");
1007   }
1008 }
1009 
getVGPRSpillSaveOpcode(unsigned Size)1010 static unsigned getVGPRSpillSaveOpcode(unsigned Size) {
1011   switch (Size) {
1012   case 4:
1013     return AMDGPU::SI_SPILL_V32_SAVE;
1014   case 8:
1015     return AMDGPU::SI_SPILL_V64_SAVE;
1016   case 12:
1017     return AMDGPU::SI_SPILL_V96_SAVE;
1018   case 16:
1019     return AMDGPU::SI_SPILL_V128_SAVE;
1020   case 20:
1021     return AMDGPU::SI_SPILL_V160_SAVE;
1022   case 32:
1023     return AMDGPU::SI_SPILL_V256_SAVE;
1024   case 64:
1025     return AMDGPU::SI_SPILL_V512_SAVE;
1026   case 128:
1027     return AMDGPU::SI_SPILL_V1024_SAVE;
1028   default:
1029     llvm_unreachable("unknown register size");
1030   }
1031 }
1032 
getAGPRSpillSaveOpcode(unsigned Size)1033 static unsigned getAGPRSpillSaveOpcode(unsigned Size) {
1034   switch (Size) {
1035   case 4:
1036     return AMDGPU::SI_SPILL_A32_SAVE;
1037   case 8:
1038     return AMDGPU::SI_SPILL_A64_SAVE;
1039   case 16:
1040     return AMDGPU::SI_SPILL_A128_SAVE;
1041   case 64:
1042     return AMDGPU::SI_SPILL_A512_SAVE;
1043   case 128:
1044     return AMDGPU::SI_SPILL_A1024_SAVE;
1045   default:
1046     llvm_unreachable("unknown register size");
1047   }
1048 }
1049 
storeRegToStackSlot(MachineBasicBlock & MBB,MachineBasicBlock::iterator MI,unsigned SrcReg,bool isKill,int FrameIndex,const TargetRegisterClass * RC,const TargetRegisterInfo * TRI) const1050 void SIInstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
1051                                       MachineBasicBlock::iterator MI,
1052                                       unsigned SrcReg, bool isKill,
1053                                       int FrameIndex,
1054                                       const TargetRegisterClass *RC,
1055                                       const TargetRegisterInfo *TRI) const {
1056   MachineFunction *MF = MBB.getParent();
1057   SIMachineFunctionInfo *MFI = MF->getInfo<SIMachineFunctionInfo>();
1058   MachineFrameInfo &FrameInfo = MF->getFrameInfo();
1059   const DebugLoc &DL = MBB.findDebugLoc(MI);
1060 
1061   unsigned Size = FrameInfo.getObjectSize(FrameIndex);
1062   unsigned Align = FrameInfo.getObjectAlignment(FrameIndex);
1063   MachinePointerInfo PtrInfo
1064     = MachinePointerInfo::getFixedStack(*MF, FrameIndex);
1065   MachineMemOperand *MMO
1066     = MF->getMachineMemOperand(PtrInfo, MachineMemOperand::MOStore,
1067                                Size, Align);
1068   unsigned SpillSize = TRI->getSpillSize(*RC);
1069 
1070   if (RI.isSGPRClass(RC)) {
1071     MFI->setHasSpilledSGPRs();
1072     assert(SrcReg != AMDGPU::M0 && "m0 should not be spilled");
1073 
1074     // We are only allowed to create one new instruction when spilling
1075     // registers, so we need to use pseudo instruction for spilling SGPRs.
1076     const MCInstrDesc &OpDesc = get(getSGPRSpillSaveOpcode(SpillSize));
1077 
1078     // The SGPR spill/restore instructions only work on number sgprs, so we need
1079     // to make sure we are using the correct register class.
1080     if (Register::isVirtualRegister(SrcReg) && SpillSize == 4) {
1081       MachineRegisterInfo &MRI = MF->getRegInfo();
1082       MRI.constrainRegClass(SrcReg, &AMDGPU::SReg_32_XM0RegClass);
1083     }
1084 
1085     BuildMI(MBB, MI, DL, OpDesc)
1086       .addReg(SrcReg, getKillRegState(isKill)) // data
1087       .addFrameIndex(FrameIndex)               // addr
1088       .addMemOperand(MMO)
1089       .addReg(MFI->getScratchRSrcReg(), RegState::Implicit)
1090       .addReg(MFI->getStackPtrOffsetReg(), RegState::Implicit);
1091     // Add the scratch resource registers as implicit uses because we may end up
1092     // needing them, and need to ensure that the reserved registers are
1093     // correctly handled.
1094     if (RI.spillSGPRToVGPR())
1095       FrameInfo.setStackID(FrameIndex, TargetStackID::SGPRSpill);
1096     return;
1097   }
1098 
1099   unsigned Opcode = RI.hasAGPRs(RC) ? getAGPRSpillSaveOpcode(SpillSize)
1100                                     : getVGPRSpillSaveOpcode(SpillSize);
1101   MFI->setHasSpilledVGPRs();
1102 
1103   auto MIB = BuildMI(MBB, MI, DL, get(Opcode));
1104   if (RI.hasAGPRs(RC)) {
1105     MachineRegisterInfo &MRI = MF->getRegInfo();
1106     Register Tmp = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
1107     MIB.addReg(Tmp, RegState::Define);
1108   }
1109   MIB.addReg(SrcReg, getKillRegState(isKill)) // data
1110      .addFrameIndex(FrameIndex)               // addr
1111      .addReg(MFI->getScratchRSrcReg())        // scratch_rsrc
1112      .addReg(MFI->getStackPtrOffsetReg())     // scratch_offset
1113      .addImm(0)                               // offset
1114      .addMemOperand(MMO);
1115 }
1116 
getSGPRSpillRestoreOpcode(unsigned Size)1117 static unsigned getSGPRSpillRestoreOpcode(unsigned Size) {
1118   switch (Size) {
1119   case 4:
1120     return AMDGPU::SI_SPILL_S32_RESTORE;
1121   case 8:
1122     return AMDGPU::SI_SPILL_S64_RESTORE;
1123   case 12:
1124     return AMDGPU::SI_SPILL_S96_RESTORE;
1125   case 16:
1126     return AMDGPU::SI_SPILL_S128_RESTORE;
1127   case 20:
1128     return AMDGPU::SI_SPILL_S160_RESTORE;
1129   case 32:
1130     return AMDGPU::SI_SPILL_S256_RESTORE;
1131   case 64:
1132     return AMDGPU::SI_SPILL_S512_RESTORE;
1133   case 128:
1134     return AMDGPU::SI_SPILL_S1024_RESTORE;
1135   default:
1136     llvm_unreachable("unknown register size");
1137   }
1138 }
1139 
getVGPRSpillRestoreOpcode(unsigned Size)1140 static unsigned getVGPRSpillRestoreOpcode(unsigned Size) {
1141   switch (Size) {
1142   case 4:
1143     return AMDGPU::SI_SPILL_V32_RESTORE;
1144   case 8:
1145     return AMDGPU::SI_SPILL_V64_RESTORE;
1146   case 12:
1147     return AMDGPU::SI_SPILL_V96_RESTORE;
1148   case 16:
1149     return AMDGPU::SI_SPILL_V128_RESTORE;
1150   case 20:
1151     return AMDGPU::SI_SPILL_V160_RESTORE;
1152   case 32:
1153     return AMDGPU::SI_SPILL_V256_RESTORE;
1154   case 64:
1155     return AMDGPU::SI_SPILL_V512_RESTORE;
1156   case 128:
1157     return AMDGPU::SI_SPILL_V1024_RESTORE;
1158   default:
1159     llvm_unreachable("unknown register size");
1160   }
1161 }
1162 
getAGPRSpillRestoreOpcode(unsigned Size)1163 static unsigned getAGPRSpillRestoreOpcode(unsigned Size) {
1164   switch (Size) {
1165   case 4:
1166     return AMDGPU::SI_SPILL_A32_RESTORE;
1167   case 8:
1168     return AMDGPU::SI_SPILL_A64_RESTORE;
1169   case 16:
1170     return AMDGPU::SI_SPILL_A128_RESTORE;
1171   case 64:
1172     return AMDGPU::SI_SPILL_A512_RESTORE;
1173   case 128:
1174     return AMDGPU::SI_SPILL_A1024_RESTORE;
1175   default:
1176     llvm_unreachable("unknown register size");
1177   }
1178 }
1179 
loadRegFromStackSlot(MachineBasicBlock & MBB,MachineBasicBlock::iterator MI,unsigned DestReg,int FrameIndex,const TargetRegisterClass * RC,const TargetRegisterInfo * TRI) const1180 void SIInstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
1181                                        MachineBasicBlock::iterator MI,
1182                                        unsigned DestReg, int FrameIndex,
1183                                        const TargetRegisterClass *RC,
1184                                        const TargetRegisterInfo *TRI) const {
1185   MachineFunction *MF = MBB.getParent();
1186   SIMachineFunctionInfo *MFI = MF->getInfo<SIMachineFunctionInfo>();
1187   MachineFrameInfo &FrameInfo = MF->getFrameInfo();
1188   const DebugLoc &DL = MBB.findDebugLoc(MI);
1189   unsigned Align = FrameInfo.getObjectAlignment(FrameIndex);
1190   unsigned Size = FrameInfo.getObjectSize(FrameIndex);
1191   unsigned SpillSize = TRI->getSpillSize(*RC);
1192 
1193   MachinePointerInfo PtrInfo
1194     = MachinePointerInfo::getFixedStack(*MF, FrameIndex);
1195 
1196   MachineMemOperand *MMO = MF->getMachineMemOperand(
1197     PtrInfo, MachineMemOperand::MOLoad, Size, Align);
1198 
1199   if (RI.isSGPRClass(RC)) {
1200     MFI->setHasSpilledSGPRs();
1201     assert(DestReg != AMDGPU::M0 && "m0 should not be reloaded into");
1202 
1203     // FIXME: Maybe this should not include a memoperand because it will be
1204     // lowered to non-memory instructions.
1205     const MCInstrDesc &OpDesc = get(getSGPRSpillRestoreOpcode(SpillSize));
1206     if (Register::isVirtualRegister(DestReg) && SpillSize == 4) {
1207       MachineRegisterInfo &MRI = MF->getRegInfo();
1208       MRI.constrainRegClass(DestReg, &AMDGPU::SReg_32_XM0RegClass);
1209     }
1210 
1211     if (RI.spillSGPRToVGPR())
1212       FrameInfo.setStackID(FrameIndex, TargetStackID::SGPRSpill);
1213     BuildMI(MBB, MI, DL, OpDesc, DestReg)
1214       .addFrameIndex(FrameIndex) // addr
1215       .addMemOperand(MMO)
1216       .addReg(MFI->getScratchRSrcReg(), RegState::Implicit)
1217       .addReg(MFI->getStackPtrOffsetReg(), RegState::Implicit);
1218     return;
1219   }
1220 
1221   unsigned Opcode = RI.hasAGPRs(RC) ? getAGPRSpillRestoreOpcode(SpillSize)
1222                                     : getVGPRSpillRestoreOpcode(SpillSize);
1223   auto MIB = BuildMI(MBB, MI, DL, get(Opcode), DestReg);
1224   if (RI.hasAGPRs(RC)) {
1225     MachineRegisterInfo &MRI = MF->getRegInfo();
1226     Register Tmp = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
1227     MIB.addReg(Tmp, RegState::Define);
1228   }
1229   MIB.addFrameIndex(FrameIndex)        // vaddr
1230      .addReg(MFI->getScratchRSrcReg()) // scratch_rsrc
1231      .addReg(MFI->getStackPtrOffsetReg()) // scratch_offset
1232      .addImm(0)                           // offset
1233      .addMemOperand(MMO);
1234 }
1235 
1236 /// \param @Offset Offset in bytes of the FrameIndex being spilled
calculateLDSSpillAddress(MachineBasicBlock & MBB,MachineInstr & MI,RegScavenger * RS,unsigned TmpReg,unsigned FrameOffset,unsigned Size) const1237 unsigned SIInstrInfo::calculateLDSSpillAddress(
1238     MachineBasicBlock &MBB, MachineInstr &MI, RegScavenger *RS, unsigned TmpReg,
1239     unsigned FrameOffset, unsigned Size) const {
1240   MachineFunction *MF = MBB.getParent();
1241   SIMachineFunctionInfo *MFI = MF->getInfo<SIMachineFunctionInfo>();
1242   const GCNSubtarget &ST = MF->getSubtarget<GCNSubtarget>();
1243   const DebugLoc &DL = MBB.findDebugLoc(MI);
1244   unsigned WorkGroupSize = MFI->getMaxFlatWorkGroupSize();
1245   unsigned WavefrontSize = ST.getWavefrontSize();
1246 
1247   unsigned TIDReg = MFI->getTIDReg();
1248   if (!MFI->hasCalculatedTID()) {
1249     MachineBasicBlock &Entry = MBB.getParent()->front();
1250     MachineBasicBlock::iterator Insert = Entry.front();
1251     const DebugLoc &DL = Insert->getDebugLoc();
1252 
1253     TIDReg = RI.findUnusedRegister(MF->getRegInfo(), &AMDGPU::VGPR_32RegClass,
1254                                    *MF);
1255     if (TIDReg == AMDGPU::NoRegister)
1256       return TIDReg;
1257 
1258     if (!AMDGPU::isShader(MF->getFunction().getCallingConv()) &&
1259         WorkGroupSize > WavefrontSize) {
1260       Register TIDIGXReg =
1261           MFI->getPreloadedReg(AMDGPUFunctionArgInfo::WORKGROUP_ID_X);
1262       Register TIDIGYReg =
1263           MFI->getPreloadedReg(AMDGPUFunctionArgInfo::WORKGROUP_ID_Y);
1264       Register TIDIGZReg =
1265           MFI->getPreloadedReg(AMDGPUFunctionArgInfo::WORKGROUP_ID_Z);
1266       Register InputPtrReg =
1267           MFI->getPreloadedReg(AMDGPUFunctionArgInfo::KERNARG_SEGMENT_PTR);
1268       for (unsigned Reg : {TIDIGXReg, TIDIGYReg, TIDIGZReg}) {
1269         if (!Entry.isLiveIn(Reg))
1270           Entry.addLiveIn(Reg);
1271       }
1272 
1273       RS->enterBasicBlock(Entry);
1274       // FIXME: Can we scavenge an SReg_64 and access the subregs?
1275       unsigned STmp0 = RS->scavengeRegister(&AMDGPU::SGPR_32RegClass, 0);
1276       unsigned STmp1 = RS->scavengeRegister(&AMDGPU::SGPR_32RegClass, 0);
1277       BuildMI(Entry, Insert, DL, get(AMDGPU::S_LOAD_DWORD_IMM), STmp0)
1278               .addReg(InputPtrReg)
1279               .addImm(SI::KernelInputOffsets::NGROUPS_Z);
1280       BuildMI(Entry, Insert, DL, get(AMDGPU::S_LOAD_DWORD_IMM), STmp1)
1281               .addReg(InputPtrReg)
1282               .addImm(SI::KernelInputOffsets::NGROUPS_Y);
1283 
1284       // NGROUPS.X * NGROUPS.Y
1285       BuildMI(Entry, Insert, DL, get(AMDGPU::S_MUL_I32), STmp1)
1286               .addReg(STmp1)
1287               .addReg(STmp0);
1288       // (NGROUPS.X * NGROUPS.Y) * TIDIG.X
1289       BuildMI(Entry, Insert, DL, get(AMDGPU::V_MUL_U32_U24_e32), TIDReg)
1290               .addReg(STmp1)
1291               .addReg(TIDIGXReg);
1292       // NGROUPS.Z * TIDIG.Y + (NGROUPS.X * NGROPUS.Y * TIDIG.X)
1293       BuildMI(Entry, Insert, DL, get(AMDGPU::V_MAD_U32_U24), TIDReg)
1294               .addReg(STmp0)
1295               .addReg(TIDIGYReg)
1296               .addReg(TIDReg);
1297       // (NGROUPS.Z * TIDIG.Y + (NGROUPS.X * NGROPUS.Y * TIDIG.X)) + TIDIG.Z
1298       getAddNoCarry(Entry, Insert, DL, TIDReg)
1299         .addReg(TIDReg)
1300         .addReg(TIDIGZReg)
1301         .addImm(0); // clamp bit
1302     } else {
1303       // Get the wave id
1304       BuildMI(Entry, Insert, DL, get(AMDGPU::V_MBCNT_LO_U32_B32_e64),
1305               TIDReg)
1306               .addImm(-1)
1307               .addImm(0);
1308 
1309       BuildMI(Entry, Insert, DL, get(AMDGPU::V_MBCNT_HI_U32_B32_e64),
1310               TIDReg)
1311               .addImm(-1)
1312               .addReg(TIDReg);
1313     }
1314 
1315     BuildMI(Entry, Insert, DL, get(AMDGPU::V_LSHLREV_B32_e32),
1316             TIDReg)
1317             .addImm(2)
1318             .addReg(TIDReg);
1319     MFI->setTIDReg(TIDReg);
1320   }
1321 
1322   // Add FrameIndex to LDS offset
1323   unsigned LDSOffset = MFI->getLDSSize() + (FrameOffset * WorkGroupSize);
1324   getAddNoCarry(MBB, MI, DL, TmpReg)
1325     .addImm(LDSOffset)
1326     .addReg(TIDReg)
1327     .addImm(0); // clamp bit
1328 
1329   return TmpReg;
1330 }
1331 
insertWaitStates(MachineBasicBlock & MBB,MachineBasicBlock::iterator MI,int Count) const1332 void SIInstrInfo::insertWaitStates(MachineBasicBlock &MBB,
1333                                    MachineBasicBlock::iterator MI,
1334                                    int Count) const {
1335   DebugLoc DL = MBB.findDebugLoc(MI);
1336   while (Count > 0) {
1337     int Arg;
1338     if (Count >= 8)
1339       Arg = 7;
1340     else
1341       Arg = Count - 1;
1342     Count -= 8;
1343     BuildMI(MBB, MI, DL, get(AMDGPU::S_NOP))
1344             .addImm(Arg);
1345   }
1346 }
1347 
insertNoop(MachineBasicBlock & MBB,MachineBasicBlock::iterator MI) const1348 void SIInstrInfo::insertNoop(MachineBasicBlock &MBB,
1349                              MachineBasicBlock::iterator MI) const {
1350   insertWaitStates(MBB, MI, 1);
1351 }
1352 
insertReturn(MachineBasicBlock & MBB) const1353 void SIInstrInfo::insertReturn(MachineBasicBlock &MBB) const {
1354   auto MF = MBB.getParent();
1355   SIMachineFunctionInfo *Info = MF->getInfo<SIMachineFunctionInfo>();
1356 
1357   assert(Info->isEntryFunction());
1358 
1359   if (MBB.succ_empty()) {
1360     bool HasNoTerminator = MBB.getFirstTerminator() == MBB.end();
1361     if (HasNoTerminator) {
1362       if (Info->returnsVoid()) {
1363         BuildMI(MBB, MBB.end(), DebugLoc(), get(AMDGPU::S_ENDPGM)).addImm(0);
1364       } else {
1365         BuildMI(MBB, MBB.end(), DebugLoc(), get(AMDGPU::SI_RETURN_TO_EPILOG));
1366       }
1367     }
1368   }
1369 }
1370 
getNumWaitStates(const MachineInstr & MI)1371 unsigned SIInstrInfo::getNumWaitStates(const MachineInstr &MI) {
1372   switch (MI.getOpcode()) {
1373   default: return 1; // FIXME: Do wait states equal cycles?
1374 
1375   case AMDGPU::S_NOP:
1376     return MI.getOperand(0).getImm() + 1;
1377   }
1378 }
1379 
expandPostRAPseudo(MachineInstr & MI) const1380 bool SIInstrInfo::expandPostRAPseudo(MachineInstr &MI) const {
1381   MachineBasicBlock &MBB = *MI.getParent();
1382   DebugLoc DL = MBB.findDebugLoc(MI);
1383   switch (MI.getOpcode()) {
1384   default: return TargetInstrInfo::expandPostRAPseudo(MI);
1385   case AMDGPU::S_MOV_B64_term:
1386     // This is only a terminator to get the correct spill code placement during
1387     // register allocation.
1388     MI.setDesc(get(AMDGPU::S_MOV_B64));
1389     break;
1390 
1391   case AMDGPU::S_MOV_B32_term:
1392     // This is only a terminator to get the correct spill code placement during
1393     // register allocation.
1394     MI.setDesc(get(AMDGPU::S_MOV_B32));
1395     break;
1396 
1397   case AMDGPU::S_XOR_B64_term:
1398     // This is only a terminator to get the correct spill code placement during
1399     // register allocation.
1400     MI.setDesc(get(AMDGPU::S_XOR_B64));
1401     break;
1402 
1403   case AMDGPU::S_XOR_B32_term:
1404     // This is only a terminator to get the correct spill code placement during
1405     // register allocation.
1406     MI.setDesc(get(AMDGPU::S_XOR_B32));
1407     break;
1408 
1409   case AMDGPU::S_OR_B32_term:
1410     // This is only a terminator to get the correct spill code placement during
1411     // register allocation.
1412     MI.setDesc(get(AMDGPU::S_OR_B32));
1413     break;
1414 
1415   case AMDGPU::S_ANDN2_B64_term:
1416     // This is only a terminator to get the correct spill code placement during
1417     // register allocation.
1418     MI.setDesc(get(AMDGPU::S_ANDN2_B64));
1419     break;
1420 
1421   case AMDGPU::S_ANDN2_B32_term:
1422     // This is only a terminator to get the correct spill code placement during
1423     // register allocation.
1424     MI.setDesc(get(AMDGPU::S_ANDN2_B32));
1425     break;
1426 
1427   case AMDGPU::V_MOV_B64_PSEUDO: {
1428     Register Dst = MI.getOperand(0).getReg();
1429     Register DstLo = RI.getSubReg(Dst, AMDGPU::sub0);
1430     Register DstHi = RI.getSubReg(Dst, AMDGPU::sub1);
1431 
1432     const MachineOperand &SrcOp = MI.getOperand(1);
1433     // FIXME: Will this work for 64-bit floating point immediates?
1434     assert(!SrcOp.isFPImm());
1435     if (SrcOp.isImm()) {
1436       APInt Imm(64, SrcOp.getImm());
1437       BuildMI(MBB, MI, DL, get(AMDGPU::V_MOV_B32_e32), DstLo)
1438         .addImm(Imm.getLoBits(32).getZExtValue())
1439         .addReg(Dst, RegState::Implicit | RegState::Define);
1440       BuildMI(MBB, MI, DL, get(AMDGPU::V_MOV_B32_e32), DstHi)
1441         .addImm(Imm.getHiBits(32).getZExtValue())
1442         .addReg(Dst, RegState::Implicit | RegState::Define);
1443     } else {
1444       assert(SrcOp.isReg());
1445       BuildMI(MBB, MI, DL, get(AMDGPU::V_MOV_B32_e32), DstLo)
1446         .addReg(RI.getSubReg(SrcOp.getReg(), AMDGPU::sub0))
1447         .addReg(Dst, RegState::Implicit | RegState::Define);
1448       BuildMI(MBB, MI, DL, get(AMDGPU::V_MOV_B32_e32), DstHi)
1449         .addReg(RI.getSubReg(SrcOp.getReg(), AMDGPU::sub1))
1450         .addReg(Dst, RegState::Implicit | RegState::Define);
1451     }
1452     MI.eraseFromParent();
1453     break;
1454   }
1455   case AMDGPU::V_MOV_B64_DPP_PSEUDO: {
1456     expandMovDPP64(MI);
1457     break;
1458   }
1459   case AMDGPU::V_SET_INACTIVE_B32: {
1460     unsigned NotOpc = ST.isWave32() ? AMDGPU::S_NOT_B32 : AMDGPU::S_NOT_B64;
1461     unsigned Exec = ST.isWave32() ? AMDGPU::EXEC_LO : AMDGPU::EXEC;
1462     BuildMI(MBB, MI, DL, get(NotOpc), Exec)
1463       .addReg(Exec);
1464     BuildMI(MBB, MI, DL, get(AMDGPU::V_MOV_B32_e32), MI.getOperand(0).getReg())
1465       .add(MI.getOperand(2));
1466     BuildMI(MBB, MI, DL, get(NotOpc), Exec)
1467       .addReg(Exec);
1468     MI.eraseFromParent();
1469     break;
1470   }
1471   case AMDGPU::V_SET_INACTIVE_B64: {
1472     unsigned NotOpc = ST.isWave32() ? AMDGPU::S_NOT_B32 : AMDGPU::S_NOT_B64;
1473     unsigned Exec = ST.isWave32() ? AMDGPU::EXEC_LO : AMDGPU::EXEC;
1474     BuildMI(MBB, MI, DL, get(NotOpc), Exec)
1475       .addReg(Exec);
1476     MachineInstr *Copy = BuildMI(MBB, MI, DL, get(AMDGPU::V_MOV_B64_PSEUDO),
1477                                  MI.getOperand(0).getReg())
1478       .add(MI.getOperand(2));
1479     expandPostRAPseudo(*Copy);
1480     BuildMI(MBB, MI, DL, get(NotOpc), Exec)
1481       .addReg(Exec);
1482     MI.eraseFromParent();
1483     break;
1484   }
1485   case AMDGPU::V_MOVRELD_B32_V1:
1486   case AMDGPU::V_MOVRELD_B32_V2:
1487   case AMDGPU::V_MOVRELD_B32_V4:
1488   case AMDGPU::V_MOVRELD_B32_V8:
1489   case AMDGPU::V_MOVRELD_B32_V16: {
1490     const MCInstrDesc &MovRelDesc = get(AMDGPU::V_MOVRELD_B32_e32);
1491     Register VecReg = MI.getOperand(0).getReg();
1492     bool IsUndef = MI.getOperand(1).isUndef();
1493     unsigned SubReg = AMDGPU::sub0 + MI.getOperand(3).getImm();
1494     assert(VecReg == MI.getOperand(1).getReg());
1495 
1496     MachineInstr *MovRel =
1497         BuildMI(MBB, MI, DL, MovRelDesc)
1498             .addReg(RI.getSubReg(VecReg, SubReg), RegState::Undef)
1499             .add(MI.getOperand(2))
1500             .addReg(VecReg, RegState::ImplicitDefine)
1501             .addReg(VecReg,
1502                     RegState::Implicit | (IsUndef ? RegState::Undef : 0));
1503 
1504     const int ImpDefIdx =
1505         MovRelDesc.getNumOperands() + MovRelDesc.getNumImplicitUses();
1506     const int ImpUseIdx = ImpDefIdx + 1;
1507     MovRel->tieOperands(ImpDefIdx, ImpUseIdx);
1508 
1509     MI.eraseFromParent();
1510     break;
1511   }
1512   case AMDGPU::SI_PC_ADD_REL_OFFSET: {
1513     MachineFunction &MF = *MBB.getParent();
1514     Register Reg = MI.getOperand(0).getReg();
1515     Register RegLo = RI.getSubReg(Reg, AMDGPU::sub0);
1516     Register RegHi = RI.getSubReg(Reg, AMDGPU::sub1);
1517 
1518     // Create a bundle so these instructions won't be re-ordered by the
1519     // post-RA scheduler.
1520     MIBundleBuilder Bundler(MBB, MI);
1521     Bundler.append(BuildMI(MF, DL, get(AMDGPU::S_GETPC_B64), Reg));
1522 
1523     // Add 32-bit offset from this instruction to the start of the
1524     // constant data.
1525     Bundler.append(BuildMI(MF, DL, get(AMDGPU::S_ADD_U32), RegLo)
1526                        .addReg(RegLo)
1527                        .add(MI.getOperand(1)));
1528 
1529     MachineInstrBuilder MIB = BuildMI(MF, DL, get(AMDGPU::S_ADDC_U32), RegHi)
1530                                   .addReg(RegHi);
1531     MIB.add(MI.getOperand(2));
1532 
1533     Bundler.append(MIB);
1534     finalizeBundle(MBB, Bundler.begin());
1535 
1536     MI.eraseFromParent();
1537     break;
1538   }
1539   case AMDGPU::ENTER_WWM: {
1540     // This only gets its own opcode so that SIPreAllocateWWMRegs can tell when
1541     // WWM is entered.
1542     MI.setDesc(get(ST.isWave32() ? AMDGPU::S_OR_SAVEEXEC_B32
1543                                  : AMDGPU::S_OR_SAVEEXEC_B64));
1544     break;
1545   }
1546   case AMDGPU::EXIT_WWM: {
1547     // This only gets its own opcode so that SIPreAllocateWWMRegs can tell when
1548     // WWM is exited.
1549     MI.setDesc(get(ST.isWave32() ? AMDGPU::S_MOV_B32 : AMDGPU::S_MOV_B64));
1550     break;
1551   }
1552   case TargetOpcode::BUNDLE: {
1553     if (!MI.mayLoad() || MI.hasUnmodeledSideEffects())
1554       return false;
1555 
1556     // If it is a load it must be a memory clause
1557     for (MachineBasicBlock::instr_iterator I = MI.getIterator();
1558          I->isBundledWithSucc(); ++I) {
1559       I->unbundleFromSucc();
1560       for (MachineOperand &MO : I->operands())
1561         if (MO.isReg())
1562           MO.setIsInternalRead(false);
1563     }
1564 
1565     MI.eraseFromParent();
1566     break;
1567   }
1568   }
1569   return true;
1570 }
1571 
1572 std::pair<MachineInstr*, MachineInstr*>
expandMovDPP64(MachineInstr & MI) const1573 SIInstrInfo::expandMovDPP64(MachineInstr &MI) const {
1574   assert (MI.getOpcode() == AMDGPU::V_MOV_B64_DPP_PSEUDO);
1575 
1576   MachineBasicBlock &MBB = *MI.getParent();
1577   DebugLoc DL = MBB.findDebugLoc(MI);
1578   MachineFunction *MF = MBB.getParent();
1579   MachineRegisterInfo &MRI = MF->getRegInfo();
1580   Register Dst = MI.getOperand(0).getReg();
1581   unsigned Part = 0;
1582   MachineInstr *Split[2];
1583 
1584 
1585   for (auto Sub : { AMDGPU::sub0, AMDGPU::sub1 }) {
1586     auto MovDPP = BuildMI(MBB, MI, DL, get(AMDGPU::V_MOV_B32_dpp));
1587     if (Dst.isPhysical()) {
1588       MovDPP.addDef(RI.getSubReg(Dst, Sub));
1589     } else {
1590       assert(MRI.isSSA());
1591       auto Tmp = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
1592       MovDPP.addDef(Tmp);
1593     }
1594 
1595     for (unsigned I = 1; I <= 2; ++I) { // old and src operands.
1596       const MachineOperand &SrcOp = MI.getOperand(I);
1597       assert(!SrcOp.isFPImm());
1598       if (SrcOp.isImm()) {
1599         APInt Imm(64, SrcOp.getImm());
1600         Imm.ashrInPlace(Part * 32);
1601         MovDPP.addImm(Imm.getLoBits(32).getZExtValue());
1602       } else {
1603         assert(SrcOp.isReg());
1604         Register Src = SrcOp.getReg();
1605         if (Src.isPhysical())
1606           MovDPP.addReg(RI.getSubReg(Src, Sub));
1607         else
1608           MovDPP.addReg(Src, SrcOp.isUndef() ? RegState::Undef : 0, Sub);
1609       }
1610     }
1611 
1612     for (unsigned I = 3; I < MI.getNumExplicitOperands(); ++I)
1613       MovDPP.addImm(MI.getOperand(I).getImm());
1614 
1615     Split[Part] = MovDPP;
1616     ++Part;
1617   }
1618 
1619   if (Dst.isVirtual())
1620     BuildMI(MBB, MI, DL, get(AMDGPU::REG_SEQUENCE), Dst)
1621       .addReg(Split[0]->getOperand(0).getReg())
1622       .addImm(AMDGPU::sub0)
1623       .addReg(Split[1]->getOperand(0).getReg())
1624       .addImm(AMDGPU::sub1);
1625 
1626   MI.eraseFromParent();
1627   return std::make_pair(Split[0], Split[1]);
1628 }
1629 
swapSourceModifiers(MachineInstr & MI,MachineOperand & Src0,unsigned Src0OpName,MachineOperand & Src1,unsigned Src1OpName) const1630 bool SIInstrInfo::swapSourceModifiers(MachineInstr &MI,
1631                                       MachineOperand &Src0,
1632                                       unsigned Src0OpName,
1633                                       MachineOperand &Src1,
1634                                       unsigned Src1OpName) const {
1635   MachineOperand *Src0Mods = getNamedOperand(MI, Src0OpName);
1636   if (!Src0Mods)
1637     return false;
1638 
1639   MachineOperand *Src1Mods = getNamedOperand(MI, Src1OpName);
1640   assert(Src1Mods &&
1641          "All commutable instructions have both src0 and src1 modifiers");
1642 
1643   int Src0ModsVal = Src0Mods->getImm();
1644   int Src1ModsVal = Src1Mods->getImm();
1645 
1646   Src1Mods->setImm(Src0ModsVal);
1647   Src0Mods->setImm(Src1ModsVal);
1648   return true;
1649 }
1650 
swapRegAndNonRegOperand(MachineInstr & MI,MachineOperand & RegOp,MachineOperand & NonRegOp)1651 static MachineInstr *swapRegAndNonRegOperand(MachineInstr &MI,
1652                                              MachineOperand &RegOp,
1653                                              MachineOperand &NonRegOp) {
1654   Register Reg = RegOp.getReg();
1655   unsigned SubReg = RegOp.getSubReg();
1656   bool IsKill = RegOp.isKill();
1657   bool IsDead = RegOp.isDead();
1658   bool IsUndef = RegOp.isUndef();
1659   bool IsDebug = RegOp.isDebug();
1660 
1661   if (NonRegOp.isImm())
1662     RegOp.ChangeToImmediate(NonRegOp.getImm());
1663   else if (NonRegOp.isFI())
1664     RegOp.ChangeToFrameIndex(NonRegOp.getIndex());
1665   else
1666     return nullptr;
1667 
1668   NonRegOp.ChangeToRegister(Reg, false, false, IsKill, IsDead, IsUndef, IsDebug);
1669   NonRegOp.setSubReg(SubReg);
1670 
1671   return &MI;
1672 }
1673 
commuteInstructionImpl(MachineInstr & MI,bool NewMI,unsigned Src0Idx,unsigned Src1Idx) const1674 MachineInstr *SIInstrInfo::commuteInstructionImpl(MachineInstr &MI, bool NewMI,
1675                                                   unsigned Src0Idx,
1676                                                   unsigned Src1Idx) const {
1677   assert(!NewMI && "this should never be used");
1678 
1679   unsigned Opc = MI.getOpcode();
1680   int CommutedOpcode = commuteOpcode(Opc);
1681   if (CommutedOpcode == -1)
1682     return nullptr;
1683 
1684   assert(AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src0) ==
1685            static_cast<int>(Src0Idx) &&
1686          AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src1) ==
1687            static_cast<int>(Src1Idx) &&
1688          "inconsistency with findCommutedOpIndices");
1689 
1690   MachineOperand &Src0 = MI.getOperand(Src0Idx);
1691   MachineOperand &Src1 = MI.getOperand(Src1Idx);
1692 
1693   MachineInstr *CommutedMI = nullptr;
1694   if (Src0.isReg() && Src1.isReg()) {
1695     if (isOperandLegal(MI, Src1Idx, &Src0)) {
1696       // Be sure to copy the source modifiers to the right place.
1697       CommutedMI
1698         = TargetInstrInfo::commuteInstructionImpl(MI, NewMI, Src0Idx, Src1Idx);
1699     }
1700 
1701   } else if (Src0.isReg() && !Src1.isReg()) {
1702     // src0 should always be able to support any operand type, so no need to
1703     // check operand legality.
1704     CommutedMI = swapRegAndNonRegOperand(MI, Src0, Src1);
1705   } else if (!Src0.isReg() && Src1.isReg()) {
1706     if (isOperandLegal(MI, Src1Idx, &Src0))
1707       CommutedMI = swapRegAndNonRegOperand(MI, Src1, Src0);
1708   } else {
1709     // FIXME: Found two non registers to commute. This does happen.
1710     return nullptr;
1711   }
1712 
1713   if (CommutedMI) {
1714     swapSourceModifiers(MI, Src0, AMDGPU::OpName::src0_modifiers,
1715                         Src1, AMDGPU::OpName::src1_modifiers);
1716 
1717     CommutedMI->setDesc(get(CommutedOpcode));
1718   }
1719 
1720   return CommutedMI;
1721 }
1722 
1723 // This needs to be implemented because the source modifiers may be inserted
1724 // between the true commutable operands, and the base
1725 // TargetInstrInfo::commuteInstruction uses it.
findCommutedOpIndices(const MachineInstr & MI,unsigned & SrcOpIdx0,unsigned & SrcOpIdx1) const1726 bool SIInstrInfo::findCommutedOpIndices(const MachineInstr &MI,
1727                                         unsigned &SrcOpIdx0,
1728                                         unsigned &SrcOpIdx1) const {
1729   return findCommutedOpIndices(MI.getDesc(), SrcOpIdx0, SrcOpIdx1);
1730 }
1731 
findCommutedOpIndices(MCInstrDesc Desc,unsigned & SrcOpIdx0,unsigned & SrcOpIdx1) const1732 bool SIInstrInfo::findCommutedOpIndices(MCInstrDesc Desc, unsigned &SrcOpIdx0,
1733                                         unsigned &SrcOpIdx1) const {
1734   if (!Desc.isCommutable())
1735     return false;
1736 
1737   unsigned Opc = Desc.getOpcode();
1738   int Src0Idx = AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src0);
1739   if (Src0Idx == -1)
1740     return false;
1741 
1742   int Src1Idx = AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src1);
1743   if (Src1Idx == -1)
1744     return false;
1745 
1746   return fixCommutedOpIndices(SrcOpIdx0, SrcOpIdx1, Src0Idx, Src1Idx);
1747 }
1748 
isBranchOffsetInRange(unsigned BranchOp,int64_t BrOffset) const1749 bool SIInstrInfo::isBranchOffsetInRange(unsigned BranchOp,
1750                                         int64_t BrOffset) const {
1751   // BranchRelaxation should never have to check s_setpc_b64 because its dest
1752   // block is unanalyzable.
1753   assert(BranchOp != AMDGPU::S_SETPC_B64);
1754 
1755   // Convert to dwords.
1756   BrOffset /= 4;
1757 
1758   // The branch instructions do PC += signext(SIMM16 * 4) + 4, so the offset is
1759   // from the next instruction.
1760   BrOffset -= 1;
1761 
1762   return isIntN(BranchOffsetBits, BrOffset);
1763 }
1764 
getBranchDestBlock(const MachineInstr & MI) const1765 MachineBasicBlock *SIInstrInfo::getBranchDestBlock(
1766   const MachineInstr &MI) const {
1767   if (MI.getOpcode() == AMDGPU::S_SETPC_B64) {
1768     // This would be a difficult analysis to perform, but can always be legal so
1769     // there's no need to analyze it.
1770     return nullptr;
1771   }
1772 
1773   return MI.getOperand(0).getMBB();
1774 }
1775 
insertIndirectBranch(MachineBasicBlock & MBB,MachineBasicBlock & DestBB,const DebugLoc & DL,int64_t BrOffset,RegScavenger * RS) const1776 unsigned SIInstrInfo::insertIndirectBranch(MachineBasicBlock &MBB,
1777                                            MachineBasicBlock &DestBB,
1778                                            const DebugLoc &DL,
1779                                            int64_t BrOffset,
1780                                            RegScavenger *RS) const {
1781   assert(RS && "RegScavenger required for long branching");
1782   assert(MBB.empty() &&
1783          "new block should be inserted for expanding unconditional branch");
1784   assert(MBB.pred_size() == 1);
1785 
1786   MachineFunction *MF = MBB.getParent();
1787   MachineRegisterInfo &MRI = MF->getRegInfo();
1788 
1789   // FIXME: Virtual register workaround for RegScavenger not working with empty
1790   // blocks.
1791   Register PCReg = MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass);
1792 
1793   auto I = MBB.end();
1794 
1795   // We need to compute the offset relative to the instruction immediately after
1796   // s_getpc_b64. Insert pc arithmetic code before last terminator.
1797   MachineInstr *GetPC = BuildMI(MBB, I, DL, get(AMDGPU::S_GETPC_B64), PCReg);
1798 
1799   // TODO: Handle > 32-bit block address.
1800   if (BrOffset >= 0) {
1801     BuildMI(MBB, I, DL, get(AMDGPU::S_ADD_U32))
1802       .addReg(PCReg, RegState::Define, AMDGPU::sub0)
1803       .addReg(PCReg, 0, AMDGPU::sub0)
1804       .addMBB(&DestBB, MO_LONG_BRANCH_FORWARD);
1805     BuildMI(MBB, I, DL, get(AMDGPU::S_ADDC_U32))
1806       .addReg(PCReg, RegState::Define, AMDGPU::sub1)
1807       .addReg(PCReg, 0, AMDGPU::sub1)
1808       .addImm(0);
1809   } else {
1810     // Backwards branch.
1811     BuildMI(MBB, I, DL, get(AMDGPU::S_SUB_U32))
1812       .addReg(PCReg, RegState::Define, AMDGPU::sub0)
1813       .addReg(PCReg, 0, AMDGPU::sub0)
1814       .addMBB(&DestBB, MO_LONG_BRANCH_BACKWARD);
1815     BuildMI(MBB, I, DL, get(AMDGPU::S_SUBB_U32))
1816       .addReg(PCReg, RegState::Define, AMDGPU::sub1)
1817       .addReg(PCReg, 0, AMDGPU::sub1)
1818       .addImm(0);
1819   }
1820 
1821   // Insert the indirect branch after the other terminator.
1822   BuildMI(&MBB, DL, get(AMDGPU::S_SETPC_B64))
1823     .addReg(PCReg);
1824 
1825   // FIXME: If spilling is necessary, this will fail because this scavenger has
1826   // no emergency stack slots. It is non-trivial to spill in this situation,
1827   // because the restore code needs to be specially placed after the
1828   // jump. BranchRelaxation then needs to be made aware of the newly inserted
1829   // block.
1830   //
1831   // If a spill is needed for the pc register pair, we need to insert a spill
1832   // restore block right before the destination block, and insert a short branch
1833   // into the old destination block's fallthrough predecessor.
1834   // e.g.:
1835   //
1836   // s_cbranch_scc0 skip_long_branch:
1837   //
1838   // long_branch_bb:
1839   //   spill s[8:9]
1840   //   s_getpc_b64 s[8:9]
1841   //   s_add_u32 s8, s8, restore_bb
1842   //   s_addc_u32 s9, s9, 0
1843   //   s_setpc_b64 s[8:9]
1844   //
1845   // skip_long_branch:
1846   //   foo;
1847   //
1848   // .....
1849   //
1850   // dest_bb_fallthrough_predecessor:
1851   // bar;
1852   // s_branch dest_bb
1853   //
1854   // restore_bb:
1855   //  restore s[8:9]
1856   //  fallthrough dest_bb
1857   ///
1858   // dest_bb:
1859   //   buzz;
1860 
1861   RS->enterBasicBlockEnd(MBB);
1862   unsigned Scav = RS->scavengeRegisterBackwards(
1863     AMDGPU::SReg_64RegClass,
1864     MachineBasicBlock::iterator(GetPC), false, 0);
1865   MRI.replaceRegWith(PCReg, Scav);
1866   MRI.clearVirtRegs();
1867   RS->setRegUsed(Scav);
1868 
1869   return 4 + 8 + 4 + 4;
1870 }
1871 
getBranchOpcode(SIInstrInfo::BranchPredicate Cond)1872 unsigned SIInstrInfo::getBranchOpcode(SIInstrInfo::BranchPredicate Cond) {
1873   switch (Cond) {
1874   case SIInstrInfo::SCC_TRUE:
1875     return AMDGPU::S_CBRANCH_SCC1;
1876   case SIInstrInfo::SCC_FALSE:
1877     return AMDGPU::S_CBRANCH_SCC0;
1878   case SIInstrInfo::VCCNZ:
1879     return AMDGPU::S_CBRANCH_VCCNZ;
1880   case SIInstrInfo::VCCZ:
1881     return AMDGPU::S_CBRANCH_VCCZ;
1882   case SIInstrInfo::EXECNZ:
1883     return AMDGPU::S_CBRANCH_EXECNZ;
1884   case SIInstrInfo::EXECZ:
1885     return AMDGPU::S_CBRANCH_EXECZ;
1886   default:
1887     llvm_unreachable("invalid branch predicate");
1888   }
1889 }
1890 
getBranchPredicate(unsigned Opcode)1891 SIInstrInfo::BranchPredicate SIInstrInfo::getBranchPredicate(unsigned Opcode) {
1892   switch (Opcode) {
1893   case AMDGPU::S_CBRANCH_SCC0:
1894     return SCC_FALSE;
1895   case AMDGPU::S_CBRANCH_SCC1:
1896     return SCC_TRUE;
1897   case AMDGPU::S_CBRANCH_VCCNZ:
1898     return VCCNZ;
1899   case AMDGPU::S_CBRANCH_VCCZ:
1900     return VCCZ;
1901   case AMDGPU::S_CBRANCH_EXECNZ:
1902     return EXECNZ;
1903   case AMDGPU::S_CBRANCH_EXECZ:
1904     return EXECZ;
1905   default:
1906     return INVALID_BR;
1907   }
1908 }
1909 
analyzeBranchImpl(MachineBasicBlock & MBB,MachineBasicBlock::iterator I,MachineBasicBlock * & TBB,MachineBasicBlock * & FBB,SmallVectorImpl<MachineOperand> & Cond,bool AllowModify) const1910 bool SIInstrInfo::analyzeBranchImpl(MachineBasicBlock &MBB,
1911                                     MachineBasicBlock::iterator I,
1912                                     MachineBasicBlock *&TBB,
1913                                     MachineBasicBlock *&FBB,
1914                                     SmallVectorImpl<MachineOperand> &Cond,
1915                                     bool AllowModify) const {
1916   if (I->getOpcode() == AMDGPU::S_BRANCH) {
1917     // Unconditional Branch
1918     TBB = I->getOperand(0).getMBB();
1919     return false;
1920   }
1921 
1922   MachineBasicBlock *CondBB = nullptr;
1923 
1924   if (I->getOpcode() == AMDGPU::SI_NON_UNIFORM_BRCOND_PSEUDO) {
1925     CondBB = I->getOperand(1).getMBB();
1926     Cond.push_back(I->getOperand(0));
1927   } else {
1928     BranchPredicate Pred = getBranchPredicate(I->getOpcode());
1929     if (Pred == INVALID_BR)
1930       return true;
1931 
1932     CondBB = I->getOperand(0).getMBB();
1933     Cond.push_back(MachineOperand::CreateImm(Pred));
1934     Cond.push_back(I->getOperand(1)); // Save the branch register.
1935   }
1936   ++I;
1937 
1938   if (I == MBB.end()) {
1939     // Conditional branch followed by fall-through.
1940     TBB = CondBB;
1941     return false;
1942   }
1943 
1944   if (I->getOpcode() == AMDGPU::S_BRANCH) {
1945     TBB = CondBB;
1946     FBB = I->getOperand(0).getMBB();
1947     return false;
1948   }
1949 
1950   return true;
1951 }
1952 
analyzeBranch(MachineBasicBlock & MBB,MachineBasicBlock * & TBB,MachineBasicBlock * & FBB,SmallVectorImpl<MachineOperand> & Cond,bool AllowModify) const1953 bool SIInstrInfo::analyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
1954                                 MachineBasicBlock *&FBB,
1955                                 SmallVectorImpl<MachineOperand> &Cond,
1956                                 bool AllowModify) const {
1957   MachineBasicBlock::iterator I = MBB.getFirstTerminator();
1958   auto E = MBB.end();
1959   if (I == E)
1960     return false;
1961 
1962   // Skip over the instructions that are artificially terminators for special
1963   // exec management.
1964   while (I != E && !I->isBranch() && !I->isReturn() &&
1965          I->getOpcode() != AMDGPU::SI_MASK_BRANCH) {
1966     switch (I->getOpcode()) {
1967     case AMDGPU::SI_MASK_BRANCH:
1968     case AMDGPU::S_MOV_B64_term:
1969     case AMDGPU::S_XOR_B64_term:
1970     case AMDGPU::S_ANDN2_B64_term:
1971     case AMDGPU::S_MOV_B32_term:
1972     case AMDGPU::S_XOR_B32_term:
1973     case AMDGPU::S_OR_B32_term:
1974     case AMDGPU::S_ANDN2_B32_term:
1975       break;
1976     case AMDGPU::SI_IF:
1977     case AMDGPU::SI_ELSE:
1978     case AMDGPU::SI_KILL_I1_TERMINATOR:
1979     case AMDGPU::SI_KILL_F32_COND_IMM_TERMINATOR:
1980       // FIXME: It's messy that these need to be considered here at all.
1981       return true;
1982     default:
1983       llvm_unreachable("unexpected non-branch terminator inst");
1984     }
1985 
1986     ++I;
1987   }
1988 
1989   if (I == E)
1990     return false;
1991 
1992   if (I->getOpcode() != AMDGPU::SI_MASK_BRANCH)
1993     return analyzeBranchImpl(MBB, I, TBB, FBB, Cond, AllowModify);
1994 
1995   ++I;
1996 
1997   // TODO: Should be able to treat as fallthrough?
1998   if (I == MBB.end())
1999     return true;
2000 
2001   if (analyzeBranchImpl(MBB, I, TBB, FBB, Cond, AllowModify))
2002     return true;
2003 
2004   MachineBasicBlock *MaskBrDest = I->getOperand(0).getMBB();
2005 
2006   // Specifically handle the case where the conditional branch is to the same
2007   // destination as the mask branch. e.g.
2008   //
2009   // si_mask_branch BB8
2010   // s_cbranch_execz BB8
2011   // s_cbranch BB9
2012   //
2013   // This is required to understand divergent loops which may need the branches
2014   // to be relaxed.
2015   if (TBB != MaskBrDest || Cond.empty())
2016     return true;
2017 
2018   auto Pred = Cond[0].getImm();
2019   return (Pred != EXECZ && Pred != EXECNZ);
2020 }
2021 
removeBranch(MachineBasicBlock & MBB,int * BytesRemoved) const2022 unsigned SIInstrInfo::removeBranch(MachineBasicBlock &MBB,
2023                                    int *BytesRemoved) const {
2024   MachineBasicBlock::iterator I = MBB.getFirstTerminator();
2025 
2026   unsigned Count = 0;
2027   unsigned RemovedSize = 0;
2028   while (I != MBB.end()) {
2029     MachineBasicBlock::iterator Next = std::next(I);
2030     if (I->getOpcode() == AMDGPU::SI_MASK_BRANCH) {
2031       I = Next;
2032       continue;
2033     }
2034 
2035     RemovedSize += getInstSizeInBytes(*I);
2036     I->eraseFromParent();
2037     ++Count;
2038     I = Next;
2039   }
2040 
2041   if (BytesRemoved)
2042     *BytesRemoved = RemovedSize;
2043 
2044   return Count;
2045 }
2046 
2047 // Copy the flags onto the implicit condition register operand.
preserveCondRegFlags(MachineOperand & CondReg,const MachineOperand & OrigCond)2048 static void preserveCondRegFlags(MachineOperand &CondReg,
2049                                  const MachineOperand &OrigCond) {
2050   CondReg.setIsUndef(OrigCond.isUndef());
2051   CondReg.setIsKill(OrigCond.isKill());
2052 }
2053 
insertBranch(MachineBasicBlock & MBB,MachineBasicBlock * TBB,MachineBasicBlock * FBB,ArrayRef<MachineOperand> Cond,const DebugLoc & DL,int * BytesAdded) const2054 unsigned SIInstrInfo::insertBranch(MachineBasicBlock &MBB,
2055                                    MachineBasicBlock *TBB,
2056                                    MachineBasicBlock *FBB,
2057                                    ArrayRef<MachineOperand> Cond,
2058                                    const DebugLoc &DL,
2059                                    int *BytesAdded) const {
2060   if (!FBB && Cond.empty()) {
2061     BuildMI(&MBB, DL, get(AMDGPU::S_BRANCH))
2062       .addMBB(TBB);
2063     if (BytesAdded)
2064       *BytesAdded = 4;
2065     return 1;
2066   }
2067 
2068   if(Cond.size() == 1 && Cond[0].isReg()) {
2069      BuildMI(&MBB, DL, get(AMDGPU::SI_NON_UNIFORM_BRCOND_PSEUDO))
2070        .add(Cond[0])
2071        .addMBB(TBB);
2072      return 1;
2073   }
2074 
2075   assert(TBB && Cond[0].isImm());
2076 
2077   unsigned Opcode
2078     = getBranchOpcode(static_cast<BranchPredicate>(Cond[0].getImm()));
2079 
2080   if (!FBB) {
2081     Cond[1].isUndef();
2082     MachineInstr *CondBr =
2083       BuildMI(&MBB, DL, get(Opcode))
2084       .addMBB(TBB);
2085 
2086     // Copy the flags onto the implicit condition register operand.
2087     preserveCondRegFlags(CondBr->getOperand(1), Cond[1]);
2088 
2089     if (BytesAdded)
2090       *BytesAdded = 4;
2091     return 1;
2092   }
2093 
2094   assert(TBB && FBB);
2095 
2096   MachineInstr *CondBr =
2097     BuildMI(&MBB, DL, get(Opcode))
2098     .addMBB(TBB);
2099   BuildMI(&MBB, DL, get(AMDGPU::S_BRANCH))
2100     .addMBB(FBB);
2101 
2102   MachineOperand &CondReg = CondBr->getOperand(1);
2103   CondReg.setIsUndef(Cond[1].isUndef());
2104   CondReg.setIsKill(Cond[1].isKill());
2105 
2106   if (BytesAdded)
2107       *BytesAdded = 8;
2108 
2109   return 2;
2110 }
2111 
reverseBranchCondition(SmallVectorImpl<MachineOperand> & Cond) const2112 bool SIInstrInfo::reverseBranchCondition(
2113   SmallVectorImpl<MachineOperand> &Cond) const {
2114   if (Cond.size() != 2) {
2115     return true;
2116   }
2117 
2118   if (Cond[0].isImm()) {
2119     Cond[0].setImm(-Cond[0].getImm());
2120     return false;
2121   }
2122 
2123   return true;
2124 }
2125 
canInsertSelect(const MachineBasicBlock & MBB,ArrayRef<MachineOperand> Cond,unsigned TrueReg,unsigned FalseReg,int & CondCycles,int & TrueCycles,int & FalseCycles) const2126 bool SIInstrInfo::canInsertSelect(const MachineBasicBlock &MBB,
2127                                   ArrayRef<MachineOperand> Cond,
2128                                   unsigned TrueReg, unsigned FalseReg,
2129                                   int &CondCycles,
2130                                   int &TrueCycles, int &FalseCycles) const {
2131   switch (Cond[0].getImm()) {
2132   case VCCNZ:
2133   case VCCZ: {
2134     const MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
2135     const TargetRegisterClass *RC = MRI.getRegClass(TrueReg);
2136     assert(MRI.getRegClass(FalseReg) == RC);
2137 
2138     int NumInsts = AMDGPU::getRegBitWidth(RC->getID()) / 32;
2139     CondCycles = TrueCycles = FalseCycles = NumInsts; // ???
2140 
2141     // Limit to equal cost for branch vs. N v_cndmask_b32s.
2142     return RI.hasVGPRs(RC) && NumInsts <= 6;
2143   }
2144   case SCC_TRUE:
2145   case SCC_FALSE: {
2146     // FIXME: We could insert for VGPRs if we could replace the original compare
2147     // with a vector one.
2148     const MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
2149     const TargetRegisterClass *RC = MRI.getRegClass(TrueReg);
2150     assert(MRI.getRegClass(FalseReg) == RC);
2151 
2152     int NumInsts = AMDGPU::getRegBitWidth(RC->getID()) / 32;
2153 
2154     // Multiples of 8 can do s_cselect_b64
2155     if (NumInsts % 2 == 0)
2156       NumInsts /= 2;
2157 
2158     CondCycles = TrueCycles = FalseCycles = NumInsts; // ???
2159     return RI.isSGPRClass(RC);
2160   }
2161   default:
2162     return false;
2163   }
2164 }
2165 
insertSelect(MachineBasicBlock & MBB,MachineBasicBlock::iterator I,const DebugLoc & DL,unsigned DstReg,ArrayRef<MachineOperand> Cond,unsigned TrueReg,unsigned FalseReg) const2166 void SIInstrInfo::insertSelect(MachineBasicBlock &MBB,
2167                                MachineBasicBlock::iterator I, const DebugLoc &DL,
2168                                unsigned DstReg, ArrayRef<MachineOperand> Cond,
2169                                unsigned TrueReg, unsigned FalseReg) const {
2170   BranchPredicate Pred = static_cast<BranchPredicate>(Cond[0].getImm());
2171   if (Pred == VCCZ || Pred == SCC_FALSE) {
2172     Pred = static_cast<BranchPredicate>(-Pred);
2173     std::swap(TrueReg, FalseReg);
2174   }
2175 
2176   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
2177   const TargetRegisterClass *DstRC = MRI.getRegClass(DstReg);
2178   unsigned DstSize = RI.getRegSizeInBits(*DstRC);
2179 
2180   if (DstSize == 32) {
2181     unsigned SelOp = Pred == SCC_TRUE ?
2182       AMDGPU::S_CSELECT_B32 : AMDGPU::V_CNDMASK_B32_e32;
2183 
2184     // Instruction's operands are backwards from what is expected.
2185     MachineInstr *Select =
2186       BuildMI(MBB, I, DL, get(SelOp), DstReg)
2187       .addReg(FalseReg)
2188       .addReg(TrueReg);
2189 
2190     preserveCondRegFlags(Select->getOperand(3), Cond[1]);
2191     return;
2192   }
2193 
2194   if (DstSize == 64 && Pred == SCC_TRUE) {
2195     MachineInstr *Select =
2196       BuildMI(MBB, I, DL, get(AMDGPU::S_CSELECT_B64), DstReg)
2197       .addReg(FalseReg)
2198       .addReg(TrueReg);
2199 
2200     preserveCondRegFlags(Select->getOperand(3), Cond[1]);
2201     return;
2202   }
2203 
2204   static const int16_t Sub0_15[] = {
2205     AMDGPU::sub0, AMDGPU::sub1, AMDGPU::sub2, AMDGPU::sub3,
2206     AMDGPU::sub4, AMDGPU::sub5, AMDGPU::sub6, AMDGPU::sub7,
2207     AMDGPU::sub8, AMDGPU::sub9, AMDGPU::sub10, AMDGPU::sub11,
2208     AMDGPU::sub12, AMDGPU::sub13, AMDGPU::sub14, AMDGPU::sub15,
2209   };
2210 
2211   static const int16_t Sub0_15_64[] = {
2212     AMDGPU::sub0_sub1, AMDGPU::sub2_sub3,
2213     AMDGPU::sub4_sub5, AMDGPU::sub6_sub7,
2214     AMDGPU::sub8_sub9, AMDGPU::sub10_sub11,
2215     AMDGPU::sub12_sub13, AMDGPU::sub14_sub15,
2216   };
2217 
2218   unsigned SelOp = AMDGPU::V_CNDMASK_B32_e32;
2219   const TargetRegisterClass *EltRC = &AMDGPU::VGPR_32RegClass;
2220   const int16_t *SubIndices = Sub0_15;
2221   int NElts = DstSize / 32;
2222 
2223   // 64-bit select is only available for SALU.
2224   // TODO: Split 96-bit into 64-bit and 32-bit, not 3x 32-bit.
2225   if (Pred == SCC_TRUE) {
2226     if (NElts % 2) {
2227       SelOp = AMDGPU::S_CSELECT_B32;
2228       EltRC = &AMDGPU::SGPR_32RegClass;
2229     } else {
2230       SelOp = AMDGPU::S_CSELECT_B64;
2231       EltRC = &AMDGPU::SGPR_64RegClass;
2232       SubIndices = Sub0_15_64;
2233       NElts /= 2;
2234     }
2235   }
2236 
2237   MachineInstrBuilder MIB = BuildMI(
2238     MBB, I, DL, get(AMDGPU::REG_SEQUENCE), DstReg);
2239 
2240   I = MIB->getIterator();
2241 
2242   SmallVector<unsigned, 8> Regs;
2243   for (int Idx = 0; Idx != NElts; ++Idx) {
2244     Register DstElt = MRI.createVirtualRegister(EltRC);
2245     Regs.push_back(DstElt);
2246 
2247     unsigned SubIdx = SubIndices[Idx];
2248 
2249     MachineInstr *Select =
2250       BuildMI(MBB, I, DL, get(SelOp), DstElt)
2251       .addReg(FalseReg, 0, SubIdx)
2252       .addReg(TrueReg, 0, SubIdx);
2253     preserveCondRegFlags(Select->getOperand(3), Cond[1]);
2254     fixImplicitOperands(*Select);
2255 
2256     MIB.addReg(DstElt)
2257        .addImm(SubIdx);
2258   }
2259 }
2260 
isFoldableCopy(const MachineInstr & MI) const2261 bool SIInstrInfo::isFoldableCopy(const MachineInstr &MI) const {
2262   switch (MI.getOpcode()) {
2263   case AMDGPU::V_MOV_B32_e32:
2264   case AMDGPU::V_MOV_B32_e64:
2265   case AMDGPU::V_MOV_B64_PSEUDO: {
2266     // If there are additional implicit register operands, this may be used for
2267     // register indexing so the source register operand isn't simply copied.
2268     unsigned NumOps = MI.getDesc().getNumOperands() +
2269       MI.getDesc().getNumImplicitUses();
2270 
2271     return MI.getNumOperands() == NumOps;
2272   }
2273   case AMDGPU::S_MOV_B32:
2274   case AMDGPU::S_MOV_B64:
2275   case AMDGPU::COPY:
2276   case AMDGPU::V_ACCVGPR_WRITE_B32:
2277   case AMDGPU::V_ACCVGPR_READ_B32:
2278     return true;
2279   default:
2280     return false;
2281   }
2282 }
2283 
getAddressSpaceForPseudoSourceKind(unsigned Kind) const2284 unsigned SIInstrInfo::getAddressSpaceForPseudoSourceKind(
2285     unsigned Kind) const {
2286   switch(Kind) {
2287   case PseudoSourceValue::Stack:
2288   case PseudoSourceValue::FixedStack:
2289     return AMDGPUAS::PRIVATE_ADDRESS;
2290   case PseudoSourceValue::ConstantPool:
2291   case PseudoSourceValue::GOT:
2292   case PseudoSourceValue::JumpTable:
2293   case PseudoSourceValue::GlobalValueCallEntry:
2294   case PseudoSourceValue::ExternalSymbolCallEntry:
2295   case PseudoSourceValue::TargetCustom:
2296     return AMDGPUAS::CONSTANT_ADDRESS;
2297   }
2298   return AMDGPUAS::FLAT_ADDRESS;
2299 }
2300 
removeModOperands(MachineInstr & MI)2301 static void removeModOperands(MachineInstr &MI) {
2302   unsigned Opc = MI.getOpcode();
2303   int Src0ModIdx = AMDGPU::getNamedOperandIdx(Opc,
2304                                               AMDGPU::OpName::src0_modifiers);
2305   int Src1ModIdx = AMDGPU::getNamedOperandIdx(Opc,
2306                                               AMDGPU::OpName::src1_modifiers);
2307   int Src2ModIdx = AMDGPU::getNamedOperandIdx(Opc,
2308                                               AMDGPU::OpName::src2_modifiers);
2309 
2310   MI.RemoveOperand(Src2ModIdx);
2311   MI.RemoveOperand(Src1ModIdx);
2312   MI.RemoveOperand(Src0ModIdx);
2313 }
2314 
FoldImmediate(MachineInstr & UseMI,MachineInstr & DefMI,unsigned Reg,MachineRegisterInfo * MRI) const2315 bool SIInstrInfo::FoldImmediate(MachineInstr &UseMI, MachineInstr &DefMI,
2316                                 unsigned Reg, MachineRegisterInfo *MRI) const {
2317   if (!MRI->hasOneNonDBGUse(Reg))
2318     return false;
2319 
2320   switch (DefMI.getOpcode()) {
2321   default:
2322     return false;
2323   case AMDGPU::S_MOV_B64:
2324     // TODO: We could fold 64-bit immediates, but this get compilicated
2325     // when there are sub-registers.
2326     return false;
2327 
2328   case AMDGPU::V_MOV_B32_e32:
2329   case AMDGPU::S_MOV_B32:
2330   case AMDGPU::V_ACCVGPR_WRITE_B32:
2331     break;
2332   }
2333 
2334   const MachineOperand *ImmOp = getNamedOperand(DefMI, AMDGPU::OpName::src0);
2335   assert(ImmOp);
2336   // FIXME: We could handle FrameIndex values here.
2337   if (!ImmOp->isImm())
2338     return false;
2339 
2340   unsigned Opc = UseMI.getOpcode();
2341   if (Opc == AMDGPU::COPY) {
2342     bool isVGPRCopy = RI.isVGPR(*MRI, UseMI.getOperand(0).getReg());
2343     unsigned NewOpc = isVGPRCopy ? AMDGPU::V_MOV_B32_e32 : AMDGPU::S_MOV_B32;
2344     if (RI.isAGPR(*MRI, UseMI.getOperand(0).getReg())) {
2345       if (!isInlineConstant(*ImmOp, AMDGPU::OPERAND_REG_INLINE_AC_INT32))
2346         return false;
2347       NewOpc = AMDGPU::V_ACCVGPR_WRITE_B32;
2348     }
2349     UseMI.setDesc(get(NewOpc));
2350     UseMI.getOperand(1).ChangeToImmediate(ImmOp->getImm());
2351     UseMI.addImplicitDefUseOperands(*UseMI.getParent()->getParent());
2352     return true;
2353   }
2354 
2355   if (Opc == AMDGPU::V_MAD_F32 || Opc == AMDGPU::V_MAC_F32_e64 ||
2356       Opc == AMDGPU::V_MAD_F16 || Opc == AMDGPU::V_MAC_F16_e64 ||
2357       Opc == AMDGPU::V_FMA_F32 || Opc == AMDGPU::V_FMAC_F32_e64 ||
2358       Opc == AMDGPU::V_FMA_F16 || Opc == AMDGPU::V_FMAC_F16_e64) {
2359     // Don't fold if we are using source or output modifiers. The new VOP2
2360     // instructions don't have them.
2361     if (hasAnyModifiersSet(UseMI))
2362       return false;
2363 
2364     // If this is a free constant, there's no reason to do this.
2365     // TODO: We could fold this here instead of letting SIFoldOperands do it
2366     // later.
2367     MachineOperand *Src0 = getNamedOperand(UseMI, AMDGPU::OpName::src0);
2368 
2369     // Any src operand can be used for the legality check.
2370     if (isInlineConstant(UseMI, *Src0, *ImmOp))
2371       return false;
2372 
2373     bool IsF32 = Opc == AMDGPU::V_MAD_F32 || Opc == AMDGPU::V_MAC_F32_e64 ||
2374                  Opc == AMDGPU::V_FMA_F32 || Opc == AMDGPU::V_FMAC_F32_e64;
2375     bool IsFMA = Opc == AMDGPU::V_FMA_F32 || Opc == AMDGPU::V_FMAC_F32_e64 ||
2376                  Opc == AMDGPU::V_FMA_F16 || Opc == AMDGPU::V_FMAC_F16_e64;
2377     MachineOperand *Src1 = getNamedOperand(UseMI, AMDGPU::OpName::src1);
2378     MachineOperand *Src2 = getNamedOperand(UseMI, AMDGPU::OpName::src2);
2379 
2380     // Multiplied part is the constant: Use v_madmk_{f16, f32}.
2381     // We should only expect these to be on src0 due to canonicalizations.
2382     if (Src0->isReg() && Src0->getReg() == Reg) {
2383       if (!Src1->isReg() || RI.isSGPRClass(MRI->getRegClass(Src1->getReg())))
2384         return false;
2385 
2386       if (!Src2->isReg() || RI.isSGPRClass(MRI->getRegClass(Src2->getReg())))
2387         return false;
2388 
2389       unsigned NewOpc =
2390         IsFMA ? (IsF32 ? AMDGPU::V_FMAMK_F32 : AMDGPU::V_FMAMK_F16)
2391               : (IsF32 ? AMDGPU::V_MADMK_F32 : AMDGPU::V_MADMK_F16);
2392       if (pseudoToMCOpcode(NewOpc) == -1)
2393         return false;
2394 
2395       // We need to swap operands 0 and 1 since madmk constant is at operand 1.
2396 
2397       const int64_t Imm = ImmOp->getImm();
2398 
2399       // FIXME: This would be a lot easier if we could return a new instruction
2400       // instead of having to modify in place.
2401 
2402       // Remove these first since they are at the end.
2403       UseMI.RemoveOperand(
2404           AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::omod));
2405       UseMI.RemoveOperand(
2406           AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::clamp));
2407 
2408       Register Src1Reg = Src1->getReg();
2409       unsigned Src1SubReg = Src1->getSubReg();
2410       Src0->setReg(Src1Reg);
2411       Src0->setSubReg(Src1SubReg);
2412       Src0->setIsKill(Src1->isKill());
2413 
2414       if (Opc == AMDGPU::V_MAC_F32_e64 ||
2415           Opc == AMDGPU::V_MAC_F16_e64 ||
2416           Opc == AMDGPU::V_FMAC_F32_e64 ||
2417           Opc == AMDGPU::V_FMAC_F16_e64)
2418         UseMI.untieRegOperand(
2419             AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src2));
2420 
2421       Src1->ChangeToImmediate(Imm);
2422 
2423       removeModOperands(UseMI);
2424       UseMI.setDesc(get(NewOpc));
2425 
2426       bool DeleteDef = MRI->hasOneNonDBGUse(Reg);
2427       if (DeleteDef)
2428         DefMI.eraseFromParent();
2429 
2430       return true;
2431     }
2432 
2433     // Added part is the constant: Use v_madak_{f16, f32}.
2434     if (Src2->isReg() && Src2->getReg() == Reg) {
2435       // Not allowed to use constant bus for another operand.
2436       // We can however allow an inline immediate as src0.
2437       bool Src0Inlined = false;
2438       if (Src0->isReg()) {
2439         // Try to inline constant if possible.
2440         // If the Def moves immediate and the use is single
2441         // We are saving VGPR here.
2442         MachineInstr *Def = MRI->getUniqueVRegDef(Src0->getReg());
2443         if (Def && Def->isMoveImmediate() &&
2444           isInlineConstant(Def->getOperand(1)) &&
2445           MRI->hasOneUse(Src0->getReg())) {
2446           Src0->ChangeToImmediate(Def->getOperand(1).getImm());
2447           Src0Inlined = true;
2448         } else if ((Register::isPhysicalRegister(Src0->getReg()) &&
2449                     (ST.getConstantBusLimit(Opc) <= 1 &&
2450                      RI.isSGPRClass(RI.getPhysRegClass(Src0->getReg())))) ||
2451                    (Register::isVirtualRegister(Src0->getReg()) &&
2452                     (ST.getConstantBusLimit(Opc) <= 1 &&
2453                      RI.isSGPRClass(MRI->getRegClass(Src0->getReg())))))
2454           return false;
2455           // VGPR is okay as Src0 - fallthrough
2456       }
2457 
2458       if (Src1->isReg() && !Src0Inlined ) {
2459         // We have one slot for inlinable constant so far - try to fill it
2460         MachineInstr *Def = MRI->getUniqueVRegDef(Src1->getReg());
2461         if (Def && Def->isMoveImmediate() &&
2462             isInlineConstant(Def->getOperand(1)) &&
2463             MRI->hasOneUse(Src1->getReg()) &&
2464             commuteInstruction(UseMI)) {
2465             Src0->ChangeToImmediate(Def->getOperand(1).getImm());
2466         } else if ((Register::isPhysicalRegister(Src1->getReg()) &&
2467                     RI.isSGPRClass(RI.getPhysRegClass(Src1->getReg()))) ||
2468                    (Register::isVirtualRegister(Src1->getReg()) &&
2469                     RI.isSGPRClass(MRI->getRegClass(Src1->getReg()))))
2470           return false;
2471           // VGPR is okay as Src1 - fallthrough
2472       }
2473 
2474       unsigned NewOpc =
2475         IsFMA ? (IsF32 ? AMDGPU::V_FMAAK_F32 : AMDGPU::V_FMAAK_F16)
2476               : (IsF32 ? AMDGPU::V_MADAK_F32 : AMDGPU::V_MADAK_F16);
2477       if (pseudoToMCOpcode(NewOpc) == -1)
2478         return false;
2479 
2480       const int64_t Imm = ImmOp->getImm();
2481 
2482       // FIXME: This would be a lot easier if we could return a new instruction
2483       // instead of having to modify in place.
2484 
2485       // Remove these first since they are at the end.
2486       UseMI.RemoveOperand(
2487           AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::omod));
2488       UseMI.RemoveOperand(
2489           AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::clamp));
2490 
2491       if (Opc == AMDGPU::V_MAC_F32_e64 ||
2492           Opc == AMDGPU::V_MAC_F16_e64 ||
2493           Opc == AMDGPU::V_FMAC_F32_e64 ||
2494           Opc == AMDGPU::V_FMAC_F16_e64)
2495         UseMI.untieRegOperand(
2496             AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src2));
2497 
2498       // ChangingToImmediate adds Src2 back to the instruction.
2499       Src2->ChangeToImmediate(Imm);
2500 
2501       // These come before src2.
2502       removeModOperands(UseMI);
2503       UseMI.setDesc(get(NewOpc));
2504       // It might happen that UseMI was commuted
2505       // and we now have SGPR as SRC1. If so 2 inlined
2506       // constant and SGPR are illegal.
2507       legalizeOperands(UseMI);
2508 
2509       bool DeleteDef = MRI->hasOneNonDBGUse(Reg);
2510       if (DeleteDef)
2511         DefMI.eraseFromParent();
2512 
2513       return true;
2514     }
2515   }
2516 
2517   return false;
2518 }
2519 
offsetsDoNotOverlap(int WidthA,int OffsetA,int WidthB,int OffsetB)2520 static bool offsetsDoNotOverlap(int WidthA, int OffsetA,
2521                                 int WidthB, int OffsetB) {
2522   int LowOffset = OffsetA < OffsetB ? OffsetA : OffsetB;
2523   int HighOffset = OffsetA < OffsetB ? OffsetB : OffsetA;
2524   int LowWidth = (LowOffset == OffsetA) ? WidthA : WidthB;
2525   return LowOffset + LowWidth <= HighOffset;
2526 }
2527 
checkInstOffsetsDoNotOverlap(const MachineInstr & MIa,const MachineInstr & MIb) const2528 bool SIInstrInfo::checkInstOffsetsDoNotOverlap(const MachineInstr &MIa,
2529                                                const MachineInstr &MIb) const {
2530   const MachineOperand *BaseOp0, *BaseOp1;
2531   int64_t Offset0, Offset1;
2532 
2533   if (getMemOperandWithOffset(MIa, BaseOp0, Offset0, &RI) &&
2534       getMemOperandWithOffset(MIb, BaseOp1, Offset1, &RI)) {
2535     if (!BaseOp0->isIdenticalTo(*BaseOp1))
2536       return false;
2537 
2538     if (!MIa.hasOneMemOperand() || !MIb.hasOneMemOperand()) {
2539       // FIXME: Handle ds_read2 / ds_write2.
2540       return false;
2541     }
2542     unsigned Width0 = (*MIa.memoperands_begin())->getSize();
2543     unsigned Width1 = (*MIb.memoperands_begin())->getSize();
2544     if (offsetsDoNotOverlap(Width0, Offset0, Width1, Offset1)) {
2545       return true;
2546     }
2547   }
2548 
2549   return false;
2550 }
2551 
areMemAccessesTriviallyDisjoint(const MachineInstr & MIa,const MachineInstr & MIb) const2552 bool SIInstrInfo::areMemAccessesTriviallyDisjoint(const MachineInstr &MIa,
2553                                                   const MachineInstr &MIb) const {
2554   assert(MIa.mayLoadOrStore() &&
2555          "MIa must load from or modify a memory location");
2556   assert(MIb.mayLoadOrStore() &&
2557          "MIb must load from or modify a memory location");
2558 
2559   if (MIa.hasUnmodeledSideEffects() || MIb.hasUnmodeledSideEffects())
2560     return false;
2561 
2562   // XXX - Can we relax this between address spaces?
2563   if (MIa.hasOrderedMemoryRef() || MIb.hasOrderedMemoryRef())
2564     return false;
2565 
2566   // TODO: Should we check the address space from the MachineMemOperand? That
2567   // would allow us to distinguish objects we know don't alias based on the
2568   // underlying address space, even if it was lowered to a different one,
2569   // e.g. private accesses lowered to use MUBUF instructions on a scratch
2570   // buffer.
2571   if (isDS(MIa)) {
2572     if (isDS(MIb))
2573       return checkInstOffsetsDoNotOverlap(MIa, MIb);
2574 
2575     return !isFLAT(MIb) || isSegmentSpecificFLAT(MIb);
2576   }
2577 
2578   if (isMUBUF(MIa) || isMTBUF(MIa)) {
2579     if (isMUBUF(MIb) || isMTBUF(MIb))
2580       return checkInstOffsetsDoNotOverlap(MIa, MIb);
2581 
2582     return !isFLAT(MIb) && !isSMRD(MIb);
2583   }
2584 
2585   if (isSMRD(MIa)) {
2586     if (isSMRD(MIb))
2587       return checkInstOffsetsDoNotOverlap(MIa, MIb);
2588 
2589     return !isFLAT(MIb) && !isMUBUF(MIa) && !isMTBUF(MIa);
2590   }
2591 
2592   if (isFLAT(MIa)) {
2593     if (isFLAT(MIb))
2594       return checkInstOffsetsDoNotOverlap(MIa, MIb);
2595 
2596     return false;
2597   }
2598 
2599   return false;
2600 }
2601 
getFoldableImm(const MachineOperand * MO)2602 static int64_t getFoldableImm(const MachineOperand* MO) {
2603   if (!MO->isReg())
2604     return false;
2605   const MachineFunction *MF = MO->getParent()->getParent()->getParent();
2606   const MachineRegisterInfo &MRI = MF->getRegInfo();
2607   auto Def = MRI.getUniqueVRegDef(MO->getReg());
2608   if (Def && Def->getOpcode() == AMDGPU::V_MOV_B32_e32 &&
2609       Def->getOperand(1).isImm())
2610     return Def->getOperand(1).getImm();
2611   return AMDGPU::NoRegister;
2612 }
2613 
convertToThreeAddress(MachineFunction::iterator & MBB,MachineInstr & MI,LiveVariables * LV) const2614 MachineInstr *SIInstrInfo::convertToThreeAddress(MachineFunction::iterator &MBB,
2615                                                  MachineInstr &MI,
2616                                                  LiveVariables *LV) const {
2617   unsigned Opc = MI.getOpcode();
2618   bool IsF16 = false;
2619   bool IsFMA = Opc == AMDGPU::V_FMAC_F32_e32 || Opc == AMDGPU::V_FMAC_F32_e64 ||
2620                Opc == AMDGPU::V_FMAC_F16_e32 || Opc == AMDGPU::V_FMAC_F16_e64;
2621 
2622   switch (Opc) {
2623   default:
2624     return nullptr;
2625   case AMDGPU::V_MAC_F16_e64:
2626   case AMDGPU::V_FMAC_F16_e64:
2627     IsF16 = true;
2628     LLVM_FALLTHROUGH;
2629   case AMDGPU::V_MAC_F32_e64:
2630   case AMDGPU::V_FMAC_F32_e64:
2631     break;
2632   case AMDGPU::V_MAC_F16_e32:
2633   case AMDGPU::V_FMAC_F16_e32:
2634     IsF16 = true;
2635     LLVM_FALLTHROUGH;
2636   case AMDGPU::V_MAC_F32_e32:
2637   case AMDGPU::V_FMAC_F32_e32: {
2638     int Src0Idx = AMDGPU::getNamedOperandIdx(MI.getOpcode(),
2639                                              AMDGPU::OpName::src0);
2640     const MachineOperand *Src0 = &MI.getOperand(Src0Idx);
2641     if (!Src0->isReg() && !Src0->isImm())
2642       return nullptr;
2643 
2644     if (Src0->isImm() && !isInlineConstant(MI, Src0Idx, *Src0))
2645       return nullptr;
2646 
2647     break;
2648   }
2649   }
2650 
2651   const MachineOperand *Dst = getNamedOperand(MI, AMDGPU::OpName::vdst);
2652   const MachineOperand *Src0 = getNamedOperand(MI, AMDGPU::OpName::src0);
2653   const MachineOperand *Src0Mods =
2654     getNamedOperand(MI, AMDGPU::OpName::src0_modifiers);
2655   const MachineOperand *Src1 = getNamedOperand(MI, AMDGPU::OpName::src1);
2656   const MachineOperand *Src1Mods =
2657     getNamedOperand(MI, AMDGPU::OpName::src1_modifiers);
2658   const MachineOperand *Src2 = getNamedOperand(MI, AMDGPU::OpName::src2);
2659   const MachineOperand *Clamp = getNamedOperand(MI, AMDGPU::OpName::clamp);
2660   const MachineOperand *Omod = getNamedOperand(MI, AMDGPU::OpName::omod);
2661 
2662   if (!Src0Mods && !Src1Mods && !Clamp && !Omod &&
2663       // If we have an SGPR input, we will violate the constant bus restriction.
2664       (ST.getConstantBusLimit(Opc) > 1 ||
2665        !Src0->isReg() ||
2666        !RI.isSGPRReg(MBB->getParent()->getRegInfo(), Src0->getReg()))) {
2667     if (auto Imm = getFoldableImm(Src2)) {
2668       unsigned NewOpc =
2669          IsFMA ? (IsF16 ? AMDGPU::V_FMAAK_F16 : AMDGPU::V_FMAAK_F32)
2670                : (IsF16 ? AMDGPU::V_MADAK_F16 : AMDGPU::V_MADAK_F32);
2671       if (pseudoToMCOpcode(NewOpc) != -1)
2672         return BuildMI(*MBB, MI, MI.getDebugLoc(), get(NewOpc))
2673                  .add(*Dst)
2674                  .add(*Src0)
2675                  .add(*Src1)
2676                  .addImm(Imm);
2677     }
2678     unsigned NewOpc =
2679       IsFMA ? (IsF16 ? AMDGPU::V_FMAMK_F16 : AMDGPU::V_FMAMK_F32)
2680             : (IsF16 ? AMDGPU::V_MADMK_F16 : AMDGPU::V_MADMK_F32);
2681     if (auto Imm = getFoldableImm(Src1)) {
2682       if (pseudoToMCOpcode(NewOpc) != -1)
2683         return BuildMI(*MBB, MI, MI.getDebugLoc(), get(NewOpc))
2684                  .add(*Dst)
2685                  .add(*Src0)
2686                  .addImm(Imm)
2687                  .add(*Src2);
2688     }
2689     if (auto Imm = getFoldableImm(Src0)) {
2690       if (pseudoToMCOpcode(NewOpc) != -1 &&
2691           isOperandLegal(MI, AMDGPU::getNamedOperandIdx(NewOpc,
2692                            AMDGPU::OpName::src0), Src1))
2693         return BuildMI(*MBB, MI, MI.getDebugLoc(), get(NewOpc))
2694                  .add(*Dst)
2695                  .add(*Src1)
2696                  .addImm(Imm)
2697                  .add(*Src2);
2698     }
2699   }
2700 
2701   unsigned NewOpc = IsFMA ? (IsF16 ? AMDGPU::V_FMA_F16 : AMDGPU::V_FMA_F32)
2702                           : (IsF16 ? AMDGPU::V_MAD_F16 : AMDGPU::V_MAD_F32);
2703   if (pseudoToMCOpcode(NewOpc) == -1)
2704     return nullptr;
2705 
2706   return BuildMI(*MBB, MI, MI.getDebugLoc(), get(NewOpc))
2707       .add(*Dst)
2708       .addImm(Src0Mods ? Src0Mods->getImm() : 0)
2709       .add(*Src0)
2710       .addImm(Src1Mods ? Src1Mods->getImm() : 0)
2711       .add(*Src1)
2712       .addImm(0) // Src mods
2713       .add(*Src2)
2714       .addImm(Clamp ? Clamp->getImm() : 0)
2715       .addImm(Omod ? Omod->getImm() : 0);
2716 }
2717 
2718 // It's not generally safe to move VALU instructions across these since it will
2719 // start using the register as a base index rather than directly.
2720 // XXX - Why isn't hasSideEffects sufficient for these?
changesVGPRIndexingMode(const MachineInstr & MI)2721 static bool changesVGPRIndexingMode(const MachineInstr &MI) {
2722   switch (MI.getOpcode()) {
2723   case AMDGPU::S_SET_GPR_IDX_ON:
2724   case AMDGPU::S_SET_GPR_IDX_MODE:
2725   case AMDGPU::S_SET_GPR_IDX_OFF:
2726     return true;
2727   default:
2728     return false;
2729   }
2730 }
2731 
isSchedulingBoundary(const MachineInstr & MI,const MachineBasicBlock * MBB,const MachineFunction & MF) const2732 bool SIInstrInfo::isSchedulingBoundary(const MachineInstr &MI,
2733                                        const MachineBasicBlock *MBB,
2734                                        const MachineFunction &MF) const {
2735   // XXX - Do we want the SP check in the base implementation?
2736 
2737   // Target-independent instructions do not have an implicit-use of EXEC, even
2738   // when they operate on VGPRs. Treating EXEC modifications as scheduling
2739   // boundaries prevents incorrect movements of such instructions.
2740   return TargetInstrInfo::isSchedulingBoundary(MI, MBB, MF) ||
2741          MI.modifiesRegister(AMDGPU::EXEC, &RI) ||
2742          MI.getOpcode() == AMDGPU::S_SETREG_IMM32_B32 ||
2743          MI.getOpcode() == AMDGPU::S_SETREG_B32 ||
2744          MI.getOpcode() == AMDGPU::S_DENORM_MODE ||
2745          changesVGPRIndexingMode(MI);
2746 }
2747 
isAlwaysGDS(uint16_t Opcode) const2748 bool SIInstrInfo::isAlwaysGDS(uint16_t Opcode) const {
2749   return Opcode == AMDGPU::DS_ORDERED_COUNT ||
2750          Opcode == AMDGPU::DS_GWS_INIT ||
2751          Opcode == AMDGPU::DS_GWS_SEMA_V ||
2752          Opcode == AMDGPU::DS_GWS_SEMA_BR ||
2753          Opcode == AMDGPU::DS_GWS_SEMA_P ||
2754          Opcode == AMDGPU::DS_GWS_SEMA_RELEASE_ALL ||
2755          Opcode == AMDGPU::DS_GWS_BARRIER;
2756 }
2757 
hasUnwantedEffectsWhenEXECEmpty(const MachineInstr & MI) const2758 bool SIInstrInfo::hasUnwantedEffectsWhenEXECEmpty(const MachineInstr &MI) const {
2759   unsigned Opcode = MI.getOpcode();
2760 
2761   if (MI.mayStore() && isSMRD(MI))
2762     return true; // scalar store or atomic
2763 
2764   // This will terminate the function when other lanes may need to continue.
2765   if (MI.isReturn())
2766     return true;
2767 
2768   // These instructions cause shader I/O that may cause hardware lockups
2769   // when executed with an empty EXEC mask.
2770   //
2771   // Note: exp with VM = DONE = 0 is automatically skipped by hardware when
2772   //       EXEC = 0, but checking for that case here seems not worth it
2773   //       given the typical code patterns.
2774   if (Opcode == AMDGPU::S_SENDMSG || Opcode == AMDGPU::S_SENDMSGHALT ||
2775       Opcode == AMDGPU::EXP || Opcode == AMDGPU::EXP_DONE ||
2776       Opcode == AMDGPU::DS_ORDERED_COUNT || Opcode == AMDGPU::S_TRAP ||
2777       Opcode == AMDGPU::DS_GWS_INIT || Opcode == AMDGPU::DS_GWS_BARRIER)
2778     return true;
2779 
2780   if (MI.isCall() || MI.isInlineAsm())
2781     return true; // conservative assumption
2782 
2783   // These are like SALU instructions in terms of effects, so it's questionable
2784   // whether we should return true for those.
2785   //
2786   // However, executing them with EXEC = 0 causes them to operate on undefined
2787   // data, which we avoid by returning true here.
2788   if (Opcode == AMDGPU::V_READFIRSTLANE_B32 || Opcode == AMDGPU::V_READLANE_B32)
2789     return true;
2790 
2791   return false;
2792 }
2793 
mayReadEXEC(const MachineRegisterInfo & MRI,const MachineInstr & MI) const2794 bool SIInstrInfo::mayReadEXEC(const MachineRegisterInfo &MRI,
2795                               const MachineInstr &MI) const {
2796   if (MI.isMetaInstruction())
2797     return false;
2798 
2799   // This won't read exec if this is an SGPR->SGPR copy.
2800   if (MI.isCopyLike()) {
2801     if (!RI.isSGPRReg(MRI, MI.getOperand(0).getReg()))
2802       return true;
2803 
2804     // Make sure this isn't copying exec as a normal operand
2805     return MI.readsRegister(AMDGPU::EXEC, &RI);
2806   }
2807 
2808   // Make a conservative assumption about the callee.
2809   if (MI.isCall())
2810     return true;
2811 
2812   // Be conservative with any unhandled generic opcodes.
2813   if (!isTargetSpecificOpcode(MI.getOpcode()))
2814     return true;
2815 
2816   return !isSALU(MI) || MI.readsRegister(AMDGPU::EXEC, &RI);
2817 }
2818 
isInlineConstant(const APInt & Imm) const2819 bool SIInstrInfo::isInlineConstant(const APInt &Imm) const {
2820   switch (Imm.getBitWidth()) {
2821   case 1: // This likely will be a condition code mask.
2822     return true;
2823 
2824   case 32:
2825     return AMDGPU::isInlinableLiteral32(Imm.getSExtValue(),
2826                                         ST.hasInv2PiInlineImm());
2827   case 64:
2828     return AMDGPU::isInlinableLiteral64(Imm.getSExtValue(),
2829                                         ST.hasInv2PiInlineImm());
2830   case 16:
2831     return ST.has16BitInsts() &&
2832            AMDGPU::isInlinableLiteral16(Imm.getSExtValue(),
2833                                         ST.hasInv2PiInlineImm());
2834   default:
2835     llvm_unreachable("invalid bitwidth");
2836   }
2837 }
2838 
isInlineConstant(const MachineOperand & MO,uint8_t OperandType) const2839 bool SIInstrInfo::isInlineConstant(const MachineOperand &MO,
2840                                    uint8_t OperandType) const {
2841   if (!MO.isImm() ||
2842       OperandType < AMDGPU::OPERAND_SRC_FIRST ||
2843       OperandType > AMDGPU::OPERAND_SRC_LAST)
2844     return false;
2845 
2846   // MachineOperand provides no way to tell the true operand size, since it only
2847   // records a 64-bit value. We need to know the size to determine if a 32-bit
2848   // floating point immediate bit pattern is legal for an integer immediate. It
2849   // would be for any 32-bit integer operand, but would not be for a 64-bit one.
2850 
2851   int64_t Imm = MO.getImm();
2852   switch (OperandType) {
2853   case AMDGPU::OPERAND_REG_IMM_INT32:
2854   case AMDGPU::OPERAND_REG_IMM_FP32:
2855   case AMDGPU::OPERAND_REG_INLINE_C_INT32:
2856   case AMDGPU::OPERAND_REG_INLINE_C_FP32:
2857   case AMDGPU::OPERAND_REG_INLINE_AC_INT32:
2858   case AMDGPU::OPERAND_REG_INLINE_AC_FP32: {
2859     int32_t Trunc = static_cast<int32_t>(Imm);
2860     return AMDGPU::isInlinableLiteral32(Trunc, ST.hasInv2PiInlineImm());
2861   }
2862   case AMDGPU::OPERAND_REG_IMM_INT64:
2863   case AMDGPU::OPERAND_REG_IMM_FP64:
2864   case AMDGPU::OPERAND_REG_INLINE_C_INT64:
2865   case AMDGPU::OPERAND_REG_INLINE_C_FP64:
2866     return AMDGPU::isInlinableLiteral64(MO.getImm(),
2867                                         ST.hasInv2PiInlineImm());
2868   case AMDGPU::OPERAND_REG_IMM_INT16:
2869   case AMDGPU::OPERAND_REG_IMM_FP16:
2870   case AMDGPU::OPERAND_REG_INLINE_C_INT16:
2871   case AMDGPU::OPERAND_REG_INLINE_C_FP16:
2872   case AMDGPU::OPERAND_REG_INLINE_AC_INT16:
2873   case AMDGPU::OPERAND_REG_INLINE_AC_FP16: {
2874     if (isInt<16>(Imm) || isUInt<16>(Imm)) {
2875       // A few special case instructions have 16-bit operands on subtargets
2876       // where 16-bit instructions are not legal.
2877       // TODO: Do the 32-bit immediates work? We shouldn't really need to handle
2878       // constants in these cases
2879       int16_t Trunc = static_cast<int16_t>(Imm);
2880       return ST.has16BitInsts() &&
2881              AMDGPU::isInlinableLiteral16(Trunc, ST.hasInv2PiInlineImm());
2882     }
2883 
2884     return false;
2885   }
2886   case AMDGPU::OPERAND_REG_IMM_V2INT16:
2887   case AMDGPU::OPERAND_REG_IMM_V2FP16:
2888   case AMDGPU::OPERAND_REG_INLINE_C_V2INT16:
2889   case AMDGPU::OPERAND_REG_INLINE_C_V2FP16:
2890   case AMDGPU::OPERAND_REG_INLINE_AC_V2INT16:
2891   case AMDGPU::OPERAND_REG_INLINE_AC_V2FP16: {
2892     uint32_t Trunc = static_cast<uint32_t>(Imm);
2893     return AMDGPU::isInlinableLiteralV216(Trunc, ST.hasInv2PiInlineImm());
2894   }
2895   default:
2896     llvm_unreachable("invalid bitwidth");
2897   }
2898 }
2899 
isLiteralConstantLike(const MachineOperand & MO,const MCOperandInfo & OpInfo) const2900 bool SIInstrInfo::isLiteralConstantLike(const MachineOperand &MO,
2901                                         const MCOperandInfo &OpInfo) const {
2902   switch (MO.getType()) {
2903   case MachineOperand::MO_Register:
2904     return false;
2905   case MachineOperand::MO_Immediate:
2906     return !isInlineConstant(MO, OpInfo);
2907   case MachineOperand::MO_FrameIndex:
2908   case MachineOperand::MO_MachineBasicBlock:
2909   case MachineOperand::MO_ExternalSymbol:
2910   case MachineOperand::MO_GlobalAddress:
2911   case MachineOperand::MO_MCSymbol:
2912     return true;
2913   default:
2914     llvm_unreachable("unexpected operand type");
2915   }
2916 }
2917 
compareMachineOp(const MachineOperand & Op0,const MachineOperand & Op1)2918 static bool compareMachineOp(const MachineOperand &Op0,
2919                              const MachineOperand &Op1) {
2920   if (Op0.getType() != Op1.getType())
2921     return false;
2922 
2923   switch (Op0.getType()) {
2924   case MachineOperand::MO_Register:
2925     return Op0.getReg() == Op1.getReg();
2926   case MachineOperand::MO_Immediate:
2927     return Op0.getImm() == Op1.getImm();
2928   default:
2929     llvm_unreachable("Didn't expect to be comparing these operand types");
2930   }
2931 }
2932 
isImmOperandLegal(const MachineInstr & MI,unsigned OpNo,const MachineOperand & MO) const2933 bool SIInstrInfo::isImmOperandLegal(const MachineInstr &MI, unsigned OpNo,
2934                                     const MachineOperand &MO) const {
2935   const MCInstrDesc &InstDesc = MI.getDesc();
2936   const MCOperandInfo &OpInfo = InstDesc.OpInfo[OpNo];
2937 
2938   assert(MO.isImm() || MO.isTargetIndex() || MO.isFI() || MO.isGlobal());
2939 
2940   if (OpInfo.OperandType == MCOI::OPERAND_IMMEDIATE)
2941     return true;
2942 
2943   if (OpInfo.RegClass < 0)
2944     return false;
2945 
2946   const MachineFunction *MF = MI.getParent()->getParent();
2947   const GCNSubtarget &ST = MF->getSubtarget<GCNSubtarget>();
2948 
2949   if (MO.isImm() && isInlineConstant(MO, OpInfo)) {
2950     if (isMAI(MI) && ST.hasMFMAInlineLiteralBug() &&
2951         OpNo ==(unsigned)AMDGPU::getNamedOperandIdx(MI.getOpcode(),
2952                                                     AMDGPU::OpName::src2))
2953       return false;
2954     return RI.opCanUseInlineConstant(OpInfo.OperandType);
2955   }
2956 
2957   if (!RI.opCanUseLiteralConstant(OpInfo.OperandType))
2958     return false;
2959 
2960   if (!isVOP3(MI) || !AMDGPU::isSISrcOperand(InstDesc, OpNo))
2961     return true;
2962 
2963   return ST.hasVOP3Literal();
2964 }
2965 
hasVALU32BitEncoding(unsigned Opcode) const2966 bool SIInstrInfo::hasVALU32BitEncoding(unsigned Opcode) const {
2967   int Op32 = AMDGPU::getVOPe32(Opcode);
2968   if (Op32 == -1)
2969     return false;
2970 
2971   return pseudoToMCOpcode(Op32) != -1;
2972 }
2973 
hasModifiers(unsigned Opcode) const2974 bool SIInstrInfo::hasModifiers(unsigned Opcode) const {
2975   // The src0_modifier operand is present on all instructions
2976   // that have modifiers.
2977 
2978   return AMDGPU::getNamedOperandIdx(Opcode,
2979                                     AMDGPU::OpName::src0_modifiers) != -1;
2980 }
2981 
hasModifiersSet(const MachineInstr & MI,unsigned OpName) const2982 bool SIInstrInfo::hasModifiersSet(const MachineInstr &MI,
2983                                   unsigned OpName) const {
2984   const MachineOperand *Mods = getNamedOperand(MI, OpName);
2985   return Mods && Mods->getImm();
2986 }
2987 
hasAnyModifiersSet(const MachineInstr & MI) const2988 bool SIInstrInfo::hasAnyModifiersSet(const MachineInstr &MI) const {
2989   return hasModifiersSet(MI, AMDGPU::OpName::src0_modifiers) ||
2990          hasModifiersSet(MI, AMDGPU::OpName::src1_modifiers) ||
2991          hasModifiersSet(MI, AMDGPU::OpName::src2_modifiers) ||
2992          hasModifiersSet(MI, AMDGPU::OpName::clamp) ||
2993          hasModifiersSet(MI, AMDGPU::OpName::omod);
2994 }
2995 
canShrink(const MachineInstr & MI,const MachineRegisterInfo & MRI) const2996 bool SIInstrInfo::canShrink(const MachineInstr &MI,
2997                             const MachineRegisterInfo &MRI) const {
2998   const MachineOperand *Src2 = getNamedOperand(MI, AMDGPU::OpName::src2);
2999   // Can't shrink instruction with three operands.
3000   // FIXME: v_cndmask_b32 has 3 operands and is shrinkable, but we need to add
3001   // a special case for it.  It can only be shrunk if the third operand
3002   // is vcc, and src0_modifiers and src1_modifiers are not set.
3003   // We should handle this the same way we handle vopc, by addding
3004   // a register allocation hint pre-regalloc and then do the shrinking
3005   // post-regalloc.
3006   if (Src2) {
3007     switch (MI.getOpcode()) {
3008       default: return false;
3009 
3010       case AMDGPU::V_ADDC_U32_e64:
3011       case AMDGPU::V_SUBB_U32_e64:
3012       case AMDGPU::V_SUBBREV_U32_e64: {
3013         const MachineOperand *Src1
3014           = getNamedOperand(MI, AMDGPU::OpName::src1);
3015         if (!Src1->isReg() || !RI.isVGPR(MRI, Src1->getReg()))
3016           return false;
3017         // Additional verification is needed for sdst/src2.
3018         return true;
3019       }
3020       case AMDGPU::V_MAC_F32_e64:
3021       case AMDGPU::V_MAC_F16_e64:
3022       case AMDGPU::V_FMAC_F32_e64:
3023       case AMDGPU::V_FMAC_F16_e64:
3024         if (!Src2->isReg() || !RI.isVGPR(MRI, Src2->getReg()) ||
3025             hasModifiersSet(MI, AMDGPU::OpName::src2_modifiers))
3026           return false;
3027         break;
3028 
3029       case AMDGPU::V_CNDMASK_B32_e64:
3030         break;
3031     }
3032   }
3033 
3034   const MachineOperand *Src1 = getNamedOperand(MI, AMDGPU::OpName::src1);
3035   if (Src1 && (!Src1->isReg() || !RI.isVGPR(MRI, Src1->getReg()) ||
3036                hasModifiersSet(MI, AMDGPU::OpName::src1_modifiers)))
3037     return false;
3038 
3039   // We don't need to check src0, all input types are legal, so just make sure
3040   // src0 isn't using any modifiers.
3041   if (hasModifiersSet(MI, AMDGPU::OpName::src0_modifiers))
3042     return false;
3043 
3044   // Can it be shrunk to a valid 32 bit opcode?
3045   if (!hasVALU32BitEncoding(MI.getOpcode()))
3046     return false;
3047 
3048   // Check output modifiers
3049   return !hasModifiersSet(MI, AMDGPU::OpName::omod) &&
3050          !hasModifiersSet(MI, AMDGPU::OpName::clamp);
3051 }
3052 
3053 // Set VCC operand with all flags from \p Orig, except for setting it as
3054 // implicit.
copyFlagsToImplicitVCC(MachineInstr & MI,const MachineOperand & Orig)3055 static void copyFlagsToImplicitVCC(MachineInstr &MI,
3056                                    const MachineOperand &Orig) {
3057 
3058   for (MachineOperand &Use : MI.implicit_operands()) {
3059     if (Use.isUse() && Use.getReg() == AMDGPU::VCC) {
3060       Use.setIsUndef(Orig.isUndef());
3061       Use.setIsKill(Orig.isKill());
3062       return;
3063     }
3064   }
3065 }
3066 
buildShrunkInst(MachineInstr & MI,unsigned Op32) const3067 MachineInstr *SIInstrInfo::buildShrunkInst(MachineInstr &MI,
3068                                            unsigned Op32) const {
3069   MachineBasicBlock *MBB = MI.getParent();;
3070   MachineInstrBuilder Inst32 =
3071     BuildMI(*MBB, MI, MI.getDebugLoc(), get(Op32));
3072 
3073   // Add the dst operand if the 32-bit encoding also has an explicit $vdst.
3074   // For VOPC instructions, this is replaced by an implicit def of vcc.
3075   int Op32DstIdx = AMDGPU::getNamedOperandIdx(Op32, AMDGPU::OpName::vdst);
3076   if (Op32DstIdx != -1) {
3077     // dst
3078     Inst32.add(MI.getOperand(0));
3079   } else {
3080     assert(((MI.getOperand(0).getReg() == AMDGPU::VCC) ||
3081             (MI.getOperand(0).getReg() == AMDGPU::VCC_LO)) &&
3082            "Unexpected case");
3083   }
3084 
3085   Inst32.add(*getNamedOperand(MI, AMDGPU::OpName::src0));
3086 
3087   const MachineOperand *Src1 = getNamedOperand(MI, AMDGPU::OpName::src1);
3088   if (Src1)
3089     Inst32.add(*Src1);
3090 
3091   const MachineOperand *Src2 = getNamedOperand(MI, AMDGPU::OpName::src2);
3092 
3093   if (Src2) {
3094     int Op32Src2Idx = AMDGPU::getNamedOperandIdx(Op32, AMDGPU::OpName::src2);
3095     if (Op32Src2Idx != -1) {
3096       Inst32.add(*Src2);
3097     } else {
3098       // In the case of V_CNDMASK_B32_e32, the explicit operand src2 is
3099       // replaced with an implicit read of vcc. This was already added
3100       // during the initial BuildMI, so find it to preserve the flags.
3101       copyFlagsToImplicitVCC(*Inst32, *Src2);
3102     }
3103   }
3104 
3105   return Inst32;
3106 }
3107 
usesConstantBus(const MachineRegisterInfo & MRI,const MachineOperand & MO,const MCOperandInfo & OpInfo) const3108 bool SIInstrInfo::usesConstantBus(const MachineRegisterInfo &MRI,
3109                                   const MachineOperand &MO,
3110                                   const MCOperandInfo &OpInfo) const {
3111   // Literal constants use the constant bus.
3112   //if (isLiteralConstantLike(MO, OpInfo))
3113   // return true;
3114   if (MO.isImm())
3115     return !isInlineConstant(MO, OpInfo);
3116 
3117   if (!MO.isReg())
3118     return true; // Misc other operands like FrameIndex
3119 
3120   if (!MO.isUse())
3121     return false;
3122 
3123   if (Register::isVirtualRegister(MO.getReg()))
3124     return RI.isSGPRClass(MRI.getRegClass(MO.getReg()));
3125 
3126   // Null is free
3127   if (MO.getReg() == AMDGPU::SGPR_NULL)
3128     return false;
3129 
3130   // SGPRs use the constant bus
3131   if (MO.isImplicit()) {
3132     return MO.getReg() == AMDGPU::M0 ||
3133            MO.getReg() == AMDGPU::VCC ||
3134            MO.getReg() == AMDGPU::VCC_LO;
3135   } else {
3136     return AMDGPU::SReg_32RegClass.contains(MO.getReg()) ||
3137            AMDGPU::SReg_64RegClass.contains(MO.getReg());
3138   }
3139 }
3140 
findImplicitSGPRRead(const MachineInstr & MI)3141 static unsigned findImplicitSGPRRead(const MachineInstr &MI) {
3142   for (const MachineOperand &MO : MI.implicit_operands()) {
3143     // We only care about reads.
3144     if (MO.isDef())
3145       continue;
3146 
3147     switch (MO.getReg()) {
3148     case AMDGPU::VCC:
3149     case AMDGPU::VCC_LO:
3150     case AMDGPU::VCC_HI:
3151     case AMDGPU::M0:
3152     case AMDGPU::FLAT_SCR:
3153       return MO.getReg();
3154 
3155     default:
3156       break;
3157     }
3158   }
3159 
3160   return AMDGPU::NoRegister;
3161 }
3162 
shouldReadExec(const MachineInstr & MI)3163 static bool shouldReadExec(const MachineInstr &MI) {
3164   if (SIInstrInfo::isVALU(MI)) {
3165     switch (MI.getOpcode()) {
3166     case AMDGPU::V_READLANE_B32:
3167     case AMDGPU::V_READLANE_B32_gfx6_gfx7:
3168     case AMDGPU::V_READLANE_B32_gfx10:
3169     case AMDGPU::V_READLANE_B32_vi:
3170     case AMDGPU::V_WRITELANE_B32:
3171     case AMDGPU::V_WRITELANE_B32_gfx6_gfx7:
3172     case AMDGPU::V_WRITELANE_B32_gfx10:
3173     case AMDGPU::V_WRITELANE_B32_vi:
3174       return false;
3175     }
3176 
3177     return true;
3178   }
3179 
3180   if (MI.isPreISelOpcode() ||
3181       SIInstrInfo::isGenericOpcode(MI.getOpcode()) ||
3182       SIInstrInfo::isSALU(MI) ||
3183       SIInstrInfo::isSMRD(MI))
3184     return false;
3185 
3186   return true;
3187 }
3188 
isSubRegOf(const SIRegisterInfo & TRI,const MachineOperand & SuperVec,const MachineOperand & SubReg)3189 static bool isSubRegOf(const SIRegisterInfo &TRI,
3190                        const MachineOperand &SuperVec,
3191                        const MachineOperand &SubReg) {
3192   if (Register::isPhysicalRegister(SubReg.getReg()))
3193     return TRI.isSubRegister(SuperVec.getReg(), SubReg.getReg());
3194 
3195   return SubReg.getSubReg() != AMDGPU::NoSubRegister &&
3196          SubReg.getReg() == SuperVec.getReg();
3197 }
3198 
verifyInstruction(const MachineInstr & MI,StringRef & ErrInfo) const3199 bool SIInstrInfo::verifyInstruction(const MachineInstr &MI,
3200                                     StringRef &ErrInfo) const {
3201   uint16_t Opcode = MI.getOpcode();
3202   if (SIInstrInfo::isGenericOpcode(MI.getOpcode()))
3203     return true;
3204 
3205   const MachineFunction *MF = MI.getParent()->getParent();
3206   const MachineRegisterInfo &MRI = MF->getRegInfo();
3207 
3208   int Src0Idx = AMDGPU::getNamedOperandIdx(Opcode, AMDGPU::OpName::src0);
3209   int Src1Idx = AMDGPU::getNamedOperandIdx(Opcode, AMDGPU::OpName::src1);
3210   int Src2Idx = AMDGPU::getNamedOperandIdx(Opcode, AMDGPU::OpName::src2);
3211 
3212   // Make sure the number of operands is correct.
3213   const MCInstrDesc &Desc = get(Opcode);
3214   if (!Desc.isVariadic() &&
3215       Desc.getNumOperands() != MI.getNumExplicitOperands()) {
3216     ErrInfo = "Instruction has wrong number of operands.";
3217     return false;
3218   }
3219 
3220   if (MI.isInlineAsm()) {
3221     // Verify register classes for inlineasm constraints.
3222     for (unsigned I = InlineAsm::MIOp_FirstOperand, E = MI.getNumOperands();
3223          I != E; ++I) {
3224       const TargetRegisterClass *RC = MI.getRegClassConstraint(I, this, &RI);
3225       if (!RC)
3226         continue;
3227 
3228       const MachineOperand &Op = MI.getOperand(I);
3229       if (!Op.isReg())
3230         continue;
3231 
3232       Register Reg = Op.getReg();
3233       if (!Register::isVirtualRegister(Reg) && !RC->contains(Reg)) {
3234         ErrInfo = "inlineasm operand has incorrect register class.";
3235         return false;
3236       }
3237     }
3238 
3239     return true;
3240   }
3241 
3242   // Make sure the register classes are correct.
3243   for (int i = 0, e = Desc.getNumOperands(); i != e; ++i) {
3244     if (MI.getOperand(i).isFPImm()) {
3245       ErrInfo = "FPImm Machine Operands are not supported. ISel should bitcast "
3246                 "all fp values to integers.";
3247       return false;
3248     }
3249 
3250     int RegClass = Desc.OpInfo[i].RegClass;
3251 
3252     switch (Desc.OpInfo[i].OperandType) {
3253     case MCOI::OPERAND_REGISTER:
3254       if (MI.getOperand(i).isImm() || MI.getOperand(i).isGlobal()) {
3255         ErrInfo = "Illegal immediate value for operand.";
3256         return false;
3257       }
3258       break;
3259     case AMDGPU::OPERAND_REG_IMM_INT32:
3260     case AMDGPU::OPERAND_REG_IMM_FP32:
3261       break;
3262     case AMDGPU::OPERAND_REG_INLINE_C_INT32:
3263     case AMDGPU::OPERAND_REG_INLINE_C_FP32:
3264     case AMDGPU::OPERAND_REG_INLINE_C_INT64:
3265     case AMDGPU::OPERAND_REG_INLINE_C_FP64:
3266     case AMDGPU::OPERAND_REG_INLINE_C_INT16:
3267     case AMDGPU::OPERAND_REG_INLINE_C_FP16:
3268     case AMDGPU::OPERAND_REG_INLINE_AC_INT32:
3269     case AMDGPU::OPERAND_REG_INLINE_AC_FP32:
3270     case AMDGPU::OPERAND_REG_INLINE_AC_INT16:
3271     case AMDGPU::OPERAND_REG_INLINE_AC_FP16: {
3272       const MachineOperand &MO = MI.getOperand(i);
3273       if (!MO.isReg() && (!MO.isImm() || !isInlineConstant(MI, i))) {
3274         ErrInfo = "Illegal immediate value for operand.";
3275         return false;
3276       }
3277       break;
3278     }
3279     case MCOI::OPERAND_IMMEDIATE:
3280     case AMDGPU::OPERAND_KIMM32:
3281       // Check if this operand is an immediate.
3282       // FrameIndex operands will be replaced by immediates, so they are
3283       // allowed.
3284       if (!MI.getOperand(i).isImm() && !MI.getOperand(i).isFI()) {
3285         ErrInfo = "Expected immediate, but got non-immediate";
3286         return false;
3287       }
3288       LLVM_FALLTHROUGH;
3289     default:
3290       continue;
3291     }
3292 
3293     if (!MI.getOperand(i).isReg())
3294       continue;
3295 
3296     if (RegClass != -1) {
3297       Register Reg = MI.getOperand(i).getReg();
3298       if (Reg == AMDGPU::NoRegister || Register::isVirtualRegister(Reg))
3299         continue;
3300 
3301       const TargetRegisterClass *RC = RI.getRegClass(RegClass);
3302       if (!RC->contains(Reg)) {
3303         ErrInfo = "Operand has incorrect register class.";
3304         return false;
3305       }
3306     }
3307   }
3308 
3309   // Verify SDWA
3310   if (isSDWA(MI)) {
3311     if (!ST.hasSDWA()) {
3312       ErrInfo = "SDWA is not supported on this target";
3313       return false;
3314     }
3315 
3316     int DstIdx = AMDGPU::getNamedOperandIdx(Opcode, AMDGPU::OpName::vdst);
3317 
3318     const int OpIndicies[] = { DstIdx, Src0Idx, Src1Idx, Src2Idx };
3319 
3320     for (int OpIdx: OpIndicies) {
3321       if (OpIdx == -1)
3322         continue;
3323       const MachineOperand &MO = MI.getOperand(OpIdx);
3324 
3325       if (!ST.hasSDWAScalar()) {
3326         // Only VGPRS on VI
3327         if (!MO.isReg() || !RI.hasVGPRs(RI.getRegClassForReg(MRI, MO.getReg()))) {
3328           ErrInfo = "Only VGPRs allowed as operands in SDWA instructions on VI";
3329           return false;
3330         }
3331       } else {
3332         // No immediates on GFX9
3333         if (!MO.isReg()) {
3334           ErrInfo = "Only reg allowed as operands in SDWA instructions on GFX9";
3335           return false;
3336         }
3337       }
3338     }
3339 
3340     if (!ST.hasSDWAOmod()) {
3341       // No omod allowed on VI
3342       const MachineOperand *OMod = getNamedOperand(MI, AMDGPU::OpName::omod);
3343       if (OMod != nullptr &&
3344         (!OMod->isImm() || OMod->getImm() != 0)) {
3345         ErrInfo = "OMod not allowed in SDWA instructions on VI";
3346         return false;
3347       }
3348     }
3349 
3350     uint16_t BasicOpcode = AMDGPU::getBasicFromSDWAOp(Opcode);
3351     if (isVOPC(BasicOpcode)) {
3352       if (!ST.hasSDWASdst() && DstIdx != -1) {
3353         // Only vcc allowed as dst on VI for VOPC
3354         const MachineOperand &Dst = MI.getOperand(DstIdx);
3355         if (!Dst.isReg() || Dst.getReg() != AMDGPU::VCC) {
3356           ErrInfo = "Only VCC allowed as dst in SDWA instructions on VI";
3357           return false;
3358         }
3359       } else if (!ST.hasSDWAOutModsVOPC()) {
3360         // No clamp allowed on GFX9 for VOPC
3361         const MachineOperand *Clamp = getNamedOperand(MI, AMDGPU::OpName::clamp);
3362         if (Clamp && (!Clamp->isImm() || Clamp->getImm() != 0)) {
3363           ErrInfo = "Clamp not allowed in VOPC SDWA instructions on VI";
3364           return false;
3365         }
3366 
3367         // No omod allowed on GFX9 for VOPC
3368         const MachineOperand *OMod = getNamedOperand(MI, AMDGPU::OpName::omod);
3369         if (OMod && (!OMod->isImm() || OMod->getImm() != 0)) {
3370           ErrInfo = "OMod not allowed in VOPC SDWA instructions on VI";
3371           return false;
3372         }
3373       }
3374     }
3375 
3376     const MachineOperand *DstUnused = getNamedOperand(MI, AMDGPU::OpName::dst_unused);
3377     if (DstUnused && DstUnused->isImm() &&
3378         DstUnused->getImm() == AMDGPU::SDWA::UNUSED_PRESERVE) {
3379       const MachineOperand &Dst = MI.getOperand(DstIdx);
3380       if (!Dst.isReg() || !Dst.isTied()) {
3381         ErrInfo = "Dst register should have tied register";
3382         return false;
3383       }
3384 
3385       const MachineOperand &TiedMO =
3386           MI.getOperand(MI.findTiedOperandIdx(DstIdx));
3387       if (!TiedMO.isReg() || !TiedMO.isImplicit() || !TiedMO.isUse()) {
3388         ErrInfo =
3389             "Dst register should be tied to implicit use of preserved register";
3390         return false;
3391       } else if (Register::isPhysicalRegister(TiedMO.getReg()) &&
3392                  Dst.getReg() != TiedMO.getReg()) {
3393         ErrInfo = "Dst register should use same physical register as preserved";
3394         return false;
3395       }
3396     }
3397   }
3398 
3399   // Verify MIMG
3400   if (isMIMG(MI.getOpcode()) && !MI.mayStore()) {
3401     // Ensure that the return type used is large enough for all the options
3402     // being used TFE/LWE require an extra result register.
3403     const MachineOperand *DMask = getNamedOperand(MI, AMDGPU::OpName::dmask);
3404     if (DMask) {
3405       uint64_t DMaskImm = DMask->getImm();
3406       uint32_t RegCount =
3407           isGather4(MI.getOpcode()) ? 4 : countPopulation(DMaskImm);
3408       const MachineOperand *TFE = getNamedOperand(MI, AMDGPU::OpName::tfe);
3409       const MachineOperand *LWE = getNamedOperand(MI, AMDGPU::OpName::lwe);
3410       const MachineOperand *D16 = getNamedOperand(MI, AMDGPU::OpName::d16);
3411 
3412       // Adjust for packed 16 bit values
3413       if (D16 && D16->getImm() && !ST.hasUnpackedD16VMem())
3414         RegCount >>= 1;
3415 
3416       // Adjust if using LWE or TFE
3417       if ((LWE && LWE->getImm()) || (TFE && TFE->getImm()))
3418         RegCount += 1;
3419 
3420       const uint32_t DstIdx =
3421           AMDGPU::getNamedOperandIdx(MI.getOpcode(), AMDGPU::OpName::vdata);
3422       const MachineOperand &Dst = MI.getOperand(DstIdx);
3423       if (Dst.isReg()) {
3424         const TargetRegisterClass *DstRC = getOpRegClass(MI, DstIdx);
3425         uint32_t DstSize = RI.getRegSizeInBits(*DstRC) / 32;
3426         if (RegCount > DstSize) {
3427           ErrInfo = "MIMG instruction returns too many registers for dst "
3428                     "register class";
3429           return false;
3430         }
3431       }
3432     }
3433   }
3434 
3435   // Verify VOP*. Ignore multiple sgpr operands on writelane.
3436   if (Desc.getOpcode() != AMDGPU::V_WRITELANE_B32
3437       && (isVOP1(MI) || isVOP2(MI) || isVOP3(MI) || isVOPC(MI) || isSDWA(MI))) {
3438     // Only look at the true operands. Only a real operand can use the constant
3439     // bus, and we don't want to check pseudo-operands like the source modifier
3440     // flags.
3441     const int OpIndices[] = { Src0Idx, Src1Idx, Src2Idx };
3442 
3443     unsigned ConstantBusCount = 0;
3444     unsigned LiteralCount = 0;
3445 
3446     if (AMDGPU::getNamedOperandIdx(Opcode, AMDGPU::OpName::imm) != -1)
3447       ++ConstantBusCount;
3448 
3449     SmallVector<unsigned, 2> SGPRsUsed;
3450     unsigned SGPRUsed = findImplicitSGPRRead(MI);
3451     if (SGPRUsed != AMDGPU::NoRegister) {
3452       ++ConstantBusCount;
3453       SGPRsUsed.push_back(SGPRUsed);
3454     }
3455 
3456     for (int OpIdx : OpIndices) {
3457       if (OpIdx == -1)
3458         break;
3459       const MachineOperand &MO = MI.getOperand(OpIdx);
3460       if (usesConstantBus(MRI, MO, MI.getDesc().OpInfo[OpIdx])) {
3461         if (MO.isReg()) {
3462           SGPRUsed = MO.getReg();
3463           if (llvm::all_of(SGPRsUsed, [this, SGPRUsed](unsigned SGPR) {
3464                 return !RI.regsOverlap(SGPRUsed, SGPR);
3465               })) {
3466             ++ConstantBusCount;
3467             SGPRsUsed.push_back(SGPRUsed);
3468           }
3469         } else {
3470           ++ConstantBusCount;
3471           ++LiteralCount;
3472         }
3473       }
3474     }
3475     const GCNSubtarget &ST = MF->getSubtarget<GCNSubtarget>();
3476     // v_writelane_b32 is an exception from constant bus restriction:
3477     // vsrc0 can be sgpr, const or m0 and lane select sgpr, m0 or inline-const
3478     if (ConstantBusCount > ST.getConstantBusLimit(Opcode) &&
3479         Opcode != AMDGPU::V_WRITELANE_B32) {
3480       ErrInfo = "VOP* instruction violates constant bus restriction";
3481       return false;
3482     }
3483 
3484     if (isVOP3(MI) && LiteralCount) {
3485       if (LiteralCount && !ST.hasVOP3Literal()) {
3486         ErrInfo = "VOP3 instruction uses literal";
3487         return false;
3488       }
3489       if (LiteralCount > 1) {
3490         ErrInfo = "VOP3 instruction uses more than one literal";
3491         return false;
3492       }
3493     }
3494   }
3495 
3496   // Special case for writelane - this can break the multiple constant bus rule,
3497   // but still can't use more than one SGPR register
3498   if (Desc.getOpcode() == AMDGPU::V_WRITELANE_B32) {
3499     unsigned SGPRCount = 0;
3500     Register SGPRUsed = AMDGPU::NoRegister;
3501 
3502     for (int OpIdx : {Src0Idx, Src1Idx, Src2Idx}) {
3503       if (OpIdx == -1)
3504         break;
3505 
3506       const MachineOperand &MO = MI.getOperand(OpIdx);
3507 
3508       if (usesConstantBus(MRI, MO, MI.getDesc().OpInfo[OpIdx])) {
3509         if (MO.isReg() && MO.getReg() != AMDGPU::M0) {
3510           if (MO.getReg() != SGPRUsed)
3511             ++SGPRCount;
3512           SGPRUsed = MO.getReg();
3513         }
3514       }
3515       if (SGPRCount > ST.getConstantBusLimit(Opcode)) {
3516         ErrInfo = "WRITELANE instruction violates constant bus restriction";
3517         return false;
3518       }
3519     }
3520   }
3521 
3522   // Verify misc. restrictions on specific instructions.
3523   if (Desc.getOpcode() == AMDGPU::V_DIV_SCALE_F32 ||
3524       Desc.getOpcode() == AMDGPU::V_DIV_SCALE_F64) {
3525     const MachineOperand &Src0 = MI.getOperand(Src0Idx);
3526     const MachineOperand &Src1 = MI.getOperand(Src1Idx);
3527     const MachineOperand &Src2 = MI.getOperand(Src2Idx);
3528     if (Src0.isReg() && Src1.isReg() && Src2.isReg()) {
3529       if (!compareMachineOp(Src0, Src1) &&
3530           !compareMachineOp(Src0, Src2)) {
3531         ErrInfo = "v_div_scale_{f32|f64} require src0 = src1 or src2";
3532         return false;
3533       }
3534     }
3535   }
3536 
3537   if (isSOP2(MI) || isSOPC(MI)) {
3538     const MachineOperand &Src0 = MI.getOperand(Src0Idx);
3539     const MachineOperand &Src1 = MI.getOperand(Src1Idx);
3540     unsigned Immediates = 0;
3541 
3542     if (!Src0.isReg() &&
3543         !isInlineConstant(Src0, Desc.OpInfo[Src0Idx].OperandType))
3544       Immediates++;
3545     if (!Src1.isReg() &&
3546         !isInlineConstant(Src1, Desc.OpInfo[Src1Idx].OperandType))
3547       Immediates++;
3548 
3549     if (Immediates > 1) {
3550       ErrInfo = "SOP2/SOPC instruction requires too many immediate constants";
3551       return false;
3552     }
3553   }
3554 
3555   if (isSOPK(MI)) {
3556     auto Op = getNamedOperand(MI, AMDGPU::OpName::simm16);
3557     if (Desc.isBranch()) {
3558       if (!Op->isMBB()) {
3559         ErrInfo = "invalid branch target for SOPK instruction";
3560         return false;
3561       }
3562     } else {
3563       uint64_t Imm = Op->getImm();
3564       if (sopkIsZext(MI)) {
3565         if (!isUInt<16>(Imm)) {
3566           ErrInfo = "invalid immediate for SOPK instruction";
3567           return false;
3568         }
3569       } else {
3570         if (!isInt<16>(Imm)) {
3571           ErrInfo = "invalid immediate for SOPK instruction";
3572           return false;
3573         }
3574       }
3575     }
3576   }
3577 
3578   if (Desc.getOpcode() == AMDGPU::V_MOVRELS_B32_e32 ||
3579       Desc.getOpcode() == AMDGPU::V_MOVRELS_B32_e64 ||
3580       Desc.getOpcode() == AMDGPU::V_MOVRELD_B32_e32 ||
3581       Desc.getOpcode() == AMDGPU::V_MOVRELD_B32_e64) {
3582     const bool IsDst = Desc.getOpcode() == AMDGPU::V_MOVRELD_B32_e32 ||
3583                        Desc.getOpcode() == AMDGPU::V_MOVRELD_B32_e64;
3584 
3585     const unsigned StaticNumOps = Desc.getNumOperands() +
3586       Desc.getNumImplicitUses();
3587     const unsigned NumImplicitOps = IsDst ? 2 : 1;
3588 
3589     // Allow additional implicit operands. This allows a fixup done by the post
3590     // RA scheduler where the main implicit operand is killed and implicit-defs
3591     // are added for sub-registers that remain live after this instruction.
3592     if (MI.getNumOperands() < StaticNumOps + NumImplicitOps) {
3593       ErrInfo = "missing implicit register operands";
3594       return false;
3595     }
3596 
3597     const MachineOperand *Dst = getNamedOperand(MI, AMDGPU::OpName::vdst);
3598     if (IsDst) {
3599       if (!Dst->isUse()) {
3600         ErrInfo = "v_movreld_b32 vdst should be a use operand";
3601         return false;
3602       }
3603 
3604       unsigned UseOpIdx;
3605       if (!MI.isRegTiedToUseOperand(StaticNumOps, &UseOpIdx) ||
3606           UseOpIdx != StaticNumOps + 1) {
3607         ErrInfo = "movrel implicit operands should be tied";
3608         return false;
3609       }
3610     }
3611 
3612     const MachineOperand &Src0 = MI.getOperand(Src0Idx);
3613     const MachineOperand &ImpUse
3614       = MI.getOperand(StaticNumOps + NumImplicitOps - 1);
3615     if (!ImpUse.isReg() || !ImpUse.isUse() ||
3616         !isSubRegOf(RI, ImpUse, IsDst ? *Dst : Src0)) {
3617       ErrInfo = "src0 should be subreg of implicit vector use";
3618       return false;
3619     }
3620   }
3621 
3622   // Make sure we aren't losing exec uses in the td files. This mostly requires
3623   // being careful when using let Uses to try to add other use registers.
3624   if (shouldReadExec(MI)) {
3625     if (!MI.hasRegisterImplicitUseOperand(AMDGPU::EXEC)) {
3626       ErrInfo = "VALU instruction does not implicitly read exec mask";
3627       return false;
3628     }
3629   }
3630 
3631   if (isSMRD(MI)) {
3632     if (MI.mayStore()) {
3633       // The register offset form of scalar stores may only use m0 as the
3634       // soffset register.
3635       const MachineOperand *Soff = getNamedOperand(MI, AMDGPU::OpName::soff);
3636       if (Soff && Soff->getReg() != AMDGPU::M0) {
3637         ErrInfo = "scalar stores must use m0 as offset register";
3638         return false;
3639       }
3640     }
3641   }
3642 
3643   if (isFLAT(MI) && !MF->getSubtarget<GCNSubtarget>().hasFlatInstOffsets()) {
3644     const MachineOperand *Offset = getNamedOperand(MI, AMDGPU::OpName::offset);
3645     if (Offset->getImm() != 0) {
3646       ErrInfo = "subtarget does not support offsets in flat instructions";
3647       return false;
3648     }
3649   }
3650 
3651   if (isMIMG(MI)) {
3652     const MachineOperand *DimOp = getNamedOperand(MI, AMDGPU::OpName::dim);
3653     if (DimOp) {
3654       int VAddr0Idx = AMDGPU::getNamedOperandIdx(Opcode,
3655                                                  AMDGPU::OpName::vaddr0);
3656       int SRsrcIdx = AMDGPU::getNamedOperandIdx(Opcode, AMDGPU::OpName::srsrc);
3657       const AMDGPU::MIMGInfo *Info = AMDGPU::getMIMGInfo(Opcode);
3658       const AMDGPU::MIMGBaseOpcodeInfo *BaseOpcode =
3659           AMDGPU::getMIMGBaseOpcodeInfo(Info->BaseOpcode);
3660       const AMDGPU::MIMGDimInfo *Dim =
3661           AMDGPU::getMIMGDimInfoByEncoding(DimOp->getImm());
3662 
3663       if (!Dim) {
3664         ErrInfo = "dim is out of range";
3665         return false;
3666       }
3667 
3668       bool IsNSA = SRsrcIdx - VAddr0Idx > 1;
3669       unsigned AddrWords = BaseOpcode->NumExtraArgs +
3670                            (BaseOpcode->Gradients ? Dim->NumGradients : 0) +
3671                            (BaseOpcode->Coordinates ? Dim->NumCoords : 0) +
3672                            (BaseOpcode->LodOrClampOrMip ? 1 : 0);
3673 
3674       unsigned VAddrWords;
3675       if (IsNSA) {
3676         VAddrWords = SRsrcIdx - VAddr0Idx;
3677       } else {
3678         const TargetRegisterClass *RC = getOpRegClass(MI, VAddr0Idx);
3679         VAddrWords = MRI.getTargetRegisterInfo()->getRegSizeInBits(*RC) / 32;
3680         if (AddrWords > 8)
3681           AddrWords = 16;
3682         else if (AddrWords > 4)
3683           AddrWords = 8;
3684         else if (AddrWords == 3 && VAddrWords == 4) {
3685           // CodeGen uses the V4 variant of instructions for three addresses,
3686           // because the selection DAG does not support non-power-of-two types.
3687           AddrWords = 4;
3688         }
3689       }
3690 
3691       if (VAddrWords != AddrWords) {
3692         ErrInfo = "bad vaddr size";
3693         return false;
3694       }
3695     }
3696   }
3697 
3698   const MachineOperand *DppCt = getNamedOperand(MI, AMDGPU::OpName::dpp_ctrl);
3699   if (DppCt) {
3700     using namespace AMDGPU::DPP;
3701 
3702     unsigned DC = DppCt->getImm();
3703     if (DC == DppCtrl::DPP_UNUSED1 || DC == DppCtrl::DPP_UNUSED2 ||
3704         DC == DppCtrl::DPP_UNUSED3 || DC > DppCtrl::DPP_LAST ||
3705         (DC >= DppCtrl::DPP_UNUSED4_FIRST && DC <= DppCtrl::DPP_UNUSED4_LAST) ||
3706         (DC >= DppCtrl::DPP_UNUSED5_FIRST && DC <= DppCtrl::DPP_UNUSED5_LAST) ||
3707         (DC >= DppCtrl::DPP_UNUSED6_FIRST && DC <= DppCtrl::DPP_UNUSED6_LAST) ||
3708         (DC >= DppCtrl::DPP_UNUSED7_FIRST && DC <= DppCtrl::DPP_UNUSED7_LAST) ||
3709         (DC >= DppCtrl::DPP_UNUSED8_FIRST && DC <= DppCtrl::DPP_UNUSED8_LAST)) {
3710       ErrInfo = "Invalid dpp_ctrl value";
3711       return false;
3712     }
3713     if (DC >= DppCtrl::WAVE_SHL1 && DC <= DppCtrl::WAVE_ROR1 &&
3714         ST.getGeneration() >= AMDGPUSubtarget::GFX10) {
3715       ErrInfo = "Invalid dpp_ctrl value: "
3716                 "wavefront shifts are not supported on GFX10+";
3717       return false;
3718     }
3719     if (DC >= DppCtrl::BCAST15 && DC <= DppCtrl::BCAST31 &&
3720         ST.getGeneration() >= AMDGPUSubtarget::GFX10) {
3721       ErrInfo = "Invalid dpp_ctrl value: "
3722                 "broadcasts are not supported on GFX10+";
3723       return false;
3724     }
3725     if (DC >= DppCtrl::ROW_SHARE_FIRST && DC <= DppCtrl::ROW_XMASK_LAST &&
3726         ST.getGeneration() < AMDGPUSubtarget::GFX10) {
3727       ErrInfo = "Invalid dpp_ctrl value: "
3728                 "row_share and row_xmask are not supported before GFX10";
3729       return false;
3730     }
3731   }
3732 
3733   return true;
3734 }
3735 
getVALUOp(const MachineInstr & MI) const3736 unsigned SIInstrInfo::getVALUOp(const MachineInstr &MI) const {
3737   switch (MI.getOpcode()) {
3738   default: return AMDGPU::INSTRUCTION_LIST_END;
3739   case AMDGPU::REG_SEQUENCE: return AMDGPU::REG_SEQUENCE;
3740   case AMDGPU::COPY: return AMDGPU::COPY;
3741   case AMDGPU::PHI: return AMDGPU::PHI;
3742   case AMDGPU::INSERT_SUBREG: return AMDGPU::INSERT_SUBREG;
3743   case AMDGPU::WQM: return AMDGPU::WQM;
3744   case AMDGPU::SOFT_WQM: return AMDGPU::SOFT_WQM;
3745   case AMDGPU::WWM: return AMDGPU::WWM;
3746   case AMDGPU::S_MOV_B32: {
3747     const MachineRegisterInfo &MRI = MI.getParent()->getParent()->getRegInfo();
3748     return MI.getOperand(1).isReg() ||
3749            RI.isAGPR(MRI, MI.getOperand(0).getReg()) ?
3750            AMDGPU::COPY : AMDGPU::V_MOV_B32_e32;
3751   }
3752   case AMDGPU::S_ADD_I32:
3753     return ST.hasAddNoCarry() ? AMDGPU::V_ADD_U32_e64 : AMDGPU::V_ADD_I32_e32;
3754   case AMDGPU::S_ADDC_U32:
3755     return AMDGPU::V_ADDC_U32_e32;
3756   case AMDGPU::S_SUB_I32:
3757     return ST.hasAddNoCarry() ? AMDGPU::V_SUB_U32_e64 : AMDGPU::V_SUB_I32_e32;
3758     // FIXME: These are not consistently handled, and selected when the carry is
3759     // used.
3760   case AMDGPU::S_ADD_U32:
3761     return AMDGPU::V_ADD_I32_e32;
3762   case AMDGPU::S_SUB_U32:
3763     return AMDGPU::V_SUB_I32_e32;
3764   case AMDGPU::S_SUBB_U32: return AMDGPU::V_SUBB_U32_e32;
3765   case AMDGPU::S_MUL_I32: return AMDGPU::V_MUL_LO_U32;
3766   case AMDGPU::S_MUL_HI_U32: return AMDGPU::V_MUL_HI_U32;
3767   case AMDGPU::S_MUL_HI_I32: return AMDGPU::V_MUL_HI_I32;
3768   case AMDGPU::S_AND_B32: return AMDGPU::V_AND_B32_e64;
3769   case AMDGPU::S_OR_B32: return AMDGPU::V_OR_B32_e64;
3770   case AMDGPU::S_XOR_B32: return AMDGPU::V_XOR_B32_e64;
3771   case AMDGPU::S_XNOR_B32:
3772     return ST.hasDLInsts() ? AMDGPU::V_XNOR_B32_e64 : AMDGPU::INSTRUCTION_LIST_END;
3773   case AMDGPU::S_MIN_I32: return AMDGPU::V_MIN_I32_e64;
3774   case AMDGPU::S_MIN_U32: return AMDGPU::V_MIN_U32_e64;
3775   case AMDGPU::S_MAX_I32: return AMDGPU::V_MAX_I32_e64;
3776   case AMDGPU::S_MAX_U32: return AMDGPU::V_MAX_U32_e64;
3777   case AMDGPU::S_ASHR_I32: return AMDGPU::V_ASHR_I32_e32;
3778   case AMDGPU::S_ASHR_I64: return AMDGPU::V_ASHR_I64;
3779   case AMDGPU::S_LSHL_B32: return AMDGPU::V_LSHL_B32_e32;
3780   case AMDGPU::S_LSHL_B64: return AMDGPU::V_LSHL_B64;
3781   case AMDGPU::S_LSHR_B32: return AMDGPU::V_LSHR_B32_e32;
3782   case AMDGPU::S_LSHR_B64: return AMDGPU::V_LSHR_B64;
3783   case AMDGPU::S_SEXT_I32_I8: return AMDGPU::V_BFE_I32;
3784   case AMDGPU::S_SEXT_I32_I16: return AMDGPU::V_BFE_I32;
3785   case AMDGPU::S_BFE_U32: return AMDGPU::V_BFE_U32;
3786   case AMDGPU::S_BFE_I32: return AMDGPU::V_BFE_I32;
3787   case AMDGPU::S_BFM_B32: return AMDGPU::V_BFM_B32_e64;
3788   case AMDGPU::S_BREV_B32: return AMDGPU::V_BFREV_B32_e32;
3789   case AMDGPU::S_NOT_B32: return AMDGPU::V_NOT_B32_e32;
3790   case AMDGPU::S_NOT_B64: return AMDGPU::V_NOT_B32_e32;
3791   case AMDGPU::S_CMP_EQ_I32: return AMDGPU::V_CMP_EQ_I32_e32;
3792   case AMDGPU::S_CMP_LG_I32: return AMDGPU::V_CMP_NE_I32_e32;
3793   case AMDGPU::S_CMP_GT_I32: return AMDGPU::V_CMP_GT_I32_e32;
3794   case AMDGPU::S_CMP_GE_I32: return AMDGPU::V_CMP_GE_I32_e32;
3795   case AMDGPU::S_CMP_LT_I32: return AMDGPU::V_CMP_LT_I32_e32;
3796   case AMDGPU::S_CMP_LE_I32: return AMDGPU::V_CMP_LE_I32_e32;
3797   case AMDGPU::S_CMP_EQ_U32: return AMDGPU::V_CMP_EQ_U32_e32;
3798   case AMDGPU::S_CMP_LG_U32: return AMDGPU::V_CMP_NE_U32_e32;
3799   case AMDGPU::S_CMP_GT_U32: return AMDGPU::V_CMP_GT_U32_e32;
3800   case AMDGPU::S_CMP_GE_U32: return AMDGPU::V_CMP_GE_U32_e32;
3801   case AMDGPU::S_CMP_LT_U32: return AMDGPU::V_CMP_LT_U32_e32;
3802   case AMDGPU::S_CMP_LE_U32: return AMDGPU::V_CMP_LE_U32_e32;
3803   case AMDGPU::S_CMP_EQ_U64: return AMDGPU::V_CMP_EQ_U64_e32;
3804   case AMDGPU::S_CMP_LG_U64: return AMDGPU::V_CMP_NE_U64_e32;
3805   case AMDGPU::S_BCNT1_I32_B32: return AMDGPU::V_BCNT_U32_B32_e64;
3806   case AMDGPU::S_FF1_I32_B32: return AMDGPU::V_FFBL_B32_e32;
3807   case AMDGPU::S_FLBIT_I32_B32: return AMDGPU::V_FFBH_U32_e32;
3808   case AMDGPU::S_FLBIT_I32: return AMDGPU::V_FFBH_I32_e64;
3809   case AMDGPU::S_CBRANCH_SCC0: return AMDGPU::S_CBRANCH_VCCZ;
3810   case AMDGPU::S_CBRANCH_SCC1: return AMDGPU::S_CBRANCH_VCCNZ;
3811   }
3812   llvm_unreachable(
3813       "Unexpected scalar opcode without corresponding vector one!");
3814 }
3815 
getOpRegClass(const MachineInstr & MI,unsigned OpNo) const3816 const TargetRegisterClass *SIInstrInfo::getOpRegClass(const MachineInstr &MI,
3817                                                       unsigned OpNo) const {
3818   const MachineRegisterInfo &MRI = MI.getParent()->getParent()->getRegInfo();
3819   const MCInstrDesc &Desc = get(MI.getOpcode());
3820   if (MI.isVariadic() || OpNo >= Desc.getNumOperands() ||
3821       Desc.OpInfo[OpNo].RegClass == -1) {
3822     Register Reg = MI.getOperand(OpNo).getReg();
3823 
3824     if (Register::isVirtualRegister(Reg))
3825       return MRI.getRegClass(Reg);
3826     return RI.getPhysRegClass(Reg);
3827   }
3828 
3829   unsigned RCID = Desc.OpInfo[OpNo].RegClass;
3830   return RI.getRegClass(RCID);
3831 }
3832 
legalizeOpWithMove(MachineInstr & MI,unsigned OpIdx) const3833 void SIInstrInfo::legalizeOpWithMove(MachineInstr &MI, unsigned OpIdx) const {
3834   MachineBasicBlock::iterator I = MI;
3835   MachineBasicBlock *MBB = MI.getParent();
3836   MachineOperand &MO = MI.getOperand(OpIdx);
3837   MachineRegisterInfo &MRI = MBB->getParent()->getRegInfo();
3838   const SIRegisterInfo *TRI =
3839       static_cast<const SIRegisterInfo*>(MRI.getTargetRegisterInfo());
3840   unsigned RCID = get(MI.getOpcode()).OpInfo[OpIdx].RegClass;
3841   const TargetRegisterClass *RC = RI.getRegClass(RCID);
3842   unsigned Size = TRI->getRegSizeInBits(*RC);
3843   unsigned Opcode = (Size == 64) ? AMDGPU::V_MOV_B64_PSEUDO : AMDGPU::V_MOV_B32_e32;
3844   if (MO.isReg())
3845     Opcode = AMDGPU::COPY;
3846   else if (RI.isSGPRClass(RC))
3847     Opcode = (Size == 64) ? AMDGPU::S_MOV_B64 : AMDGPU::S_MOV_B32;
3848 
3849   const TargetRegisterClass *VRC = RI.getEquivalentVGPRClass(RC);
3850   if (RI.getCommonSubClass(&AMDGPU::VReg_64RegClass, VRC))
3851     VRC = &AMDGPU::VReg_64RegClass;
3852   else
3853     VRC = &AMDGPU::VGPR_32RegClass;
3854 
3855   Register Reg = MRI.createVirtualRegister(VRC);
3856   DebugLoc DL = MBB->findDebugLoc(I);
3857   BuildMI(*MI.getParent(), I, DL, get(Opcode), Reg).add(MO);
3858   MO.ChangeToRegister(Reg, false);
3859 }
3860 
buildExtractSubReg(MachineBasicBlock::iterator MI,MachineRegisterInfo & MRI,MachineOperand & SuperReg,const TargetRegisterClass * SuperRC,unsigned SubIdx,const TargetRegisterClass * SubRC) const3861 unsigned SIInstrInfo::buildExtractSubReg(MachineBasicBlock::iterator MI,
3862                                          MachineRegisterInfo &MRI,
3863                                          MachineOperand &SuperReg,
3864                                          const TargetRegisterClass *SuperRC,
3865                                          unsigned SubIdx,
3866                                          const TargetRegisterClass *SubRC)
3867                                          const {
3868   MachineBasicBlock *MBB = MI->getParent();
3869   DebugLoc DL = MI->getDebugLoc();
3870   Register SubReg = MRI.createVirtualRegister(SubRC);
3871 
3872   if (SuperReg.getSubReg() == AMDGPU::NoSubRegister) {
3873     BuildMI(*MBB, MI, DL, get(TargetOpcode::COPY), SubReg)
3874       .addReg(SuperReg.getReg(), 0, SubIdx);
3875     return SubReg;
3876   }
3877 
3878   // Just in case the super register is itself a sub-register, copy it to a new
3879   // value so we don't need to worry about merging its subreg index with the
3880   // SubIdx passed to this function. The register coalescer should be able to
3881   // eliminate this extra copy.
3882   Register NewSuperReg = MRI.createVirtualRegister(SuperRC);
3883 
3884   BuildMI(*MBB, MI, DL, get(TargetOpcode::COPY), NewSuperReg)
3885     .addReg(SuperReg.getReg(), 0, SuperReg.getSubReg());
3886 
3887   BuildMI(*MBB, MI, DL, get(TargetOpcode::COPY), SubReg)
3888     .addReg(NewSuperReg, 0, SubIdx);
3889 
3890   return SubReg;
3891 }
3892 
buildExtractSubRegOrImm(MachineBasicBlock::iterator MII,MachineRegisterInfo & MRI,MachineOperand & Op,const TargetRegisterClass * SuperRC,unsigned SubIdx,const TargetRegisterClass * SubRC) const3893 MachineOperand SIInstrInfo::buildExtractSubRegOrImm(
3894   MachineBasicBlock::iterator MII,
3895   MachineRegisterInfo &MRI,
3896   MachineOperand &Op,
3897   const TargetRegisterClass *SuperRC,
3898   unsigned SubIdx,
3899   const TargetRegisterClass *SubRC) const {
3900   if (Op.isImm()) {
3901     if (SubIdx == AMDGPU::sub0)
3902       return MachineOperand::CreateImm(static_cast<int32_t>(Op.getImm()));
3903     if (SubIdx == AMDGPU::sub1)
3904       return MachineOperand::CreateImm(static_cast<int32_t>(Op.getImm() >> 32));
3905 
3906     llvm_unreachable("Unhandled register index for immediate");
3907   }
3908 
3909   unsigned SubReg = buildExtractSubReg(MII, MRI, Op, SuperRC,
3910                                        SubIdx, SubRC);
3911   return MachineOperand::CreateReg(SubReg, false);
3912 }
3913 
3914 // Change the order of operands from (0, 1, 2) to (0, 2, 1)
swapOperands(MachineInstr & Inst) const3915 void SIInstrInfo::swapOperands(MachineInstr &Inst) const {
3916   assert(Inst.getNumExplicitOperands() == 3);
3917   MachineOperand Op1 = Inst.getOperand(1);
3918   Inst.RemoveOperand(1);
3919   Inst.addOperand(Op1);
3920 }
3921 
isLegalRegOperand(const MachineRegisterInfo & MRI,const MCOperandInfo & OpInfo,const MachineOperand & MO) const3922 bool SIInstrInfo::isLegalRegOperand(const MachineRegisterInfo &MRI,
3923                                     const MCOperandInfo &OpInfo,
3924                                     const MachineOperand &MO) const {
3925   if (!MO.isReg())
3926     return false;
3927 
3928   Register Reg = MO.getReg();
3929   const TargetRegisterClass *RC = Register::isVirtualRegister(Reg)
3930                                       ? MRI.getRegClass(Reg)
3931                                       : RI.getPhysRegClass(Reg);
3932 
3933   const TargetRegisterClass *DRC = RI.getRegClass(OpInfo.RegClass);
3934   if (MO.getSubReg()) {
3935     const MachineFunction *MF = MO.getParent()->getParent()->getParent();
3936     const TargetRegisterClass *SuperRC = RI.getLargestLegalSuperClass(RC, *MF);
3937     if (!SuperRC)
3938       return false;
3939 
3940     DRC = RI.getMatchingSuperRegClass(SuperRC, DRC, MO.getSubReg());
3941     if (!DRC)
3942       return false;
3943   }
3944   return RC->hasSuperClassEq(DRC);
3945 }
3946 
isLegalVSrcOperand(const MachineRegisterInfo & MRI,const MCOperandInfo & OpInfo,const MachineOperand & MO) const3947 bool SIInstrInfo::isLegalVSrcOperand(const MachineRegisterInfo &MRI,
3948                                      const MCOperandInfo &OpInfo,
3949                                      const MachineOperand &MO) const {
3950   if (MO.isReg())
3951     return isLegalRegOperand(MRI, OpInfo, MO);
3952 
3953   // Handle non-register types that are treated like immediates.
3954   assert(MO.isImm() || MO.isTargetIndex() || MO.isFI() || MO.isGlobal());
3955   return true;
3956 }
3957 
isOperandLegal(const MachineInstr & MI,unsigned OpIdx,const MachineOperand * MO) const3958 bool SIInstrInfo::isOperandLegal(const MachineInstr &MI, unsigned OpIdx,
3959                                  const MachineOperand *MO) const {
3960   const MachineFunction &MF = *MI.getParent()->getParent();
3961   const MachineRegisterInfo &MRI = MF.getRegInfo();
3962   const MCInstrDesc &InstDesc = MI.getDesc();
3963   const MCOperandInfo &OpInfo = InstDesc.OpInfo[OpIdx];
3964   const GCNSubtarget &ST = MF.getSubtarget<GCNSubtarget>();
3965   const TargetRegisterClass *DefinedRC =
3966       OpInfo.RegClass != -1 ? RI.getRegClass(OpInfo.RegClass) : nullptr;
3967   if (!MO)
3968     MO = &MI.getOperand(OpIdx);
3969 
3970   int ConstantBusLimit = ST.getConstantBusLimit(MI.getOpcode());
3971   int VOP3LiteralLimit = ST.hasVOP3Literal() ? 1 : 0;
3972   if (isVALU(MI) && usesConstantBus(MRI, *MO, OpInfo)) {
3973     if (isVOP3(MI) && isLiteralConstantLike(*MO, OpInfo) && !VOP3LiteralLimit--)
3974       return false;
3975 
3976     SmallDenseSet<RegSubRegPair> SGPRsUsed;
3977     if (MO->isReg())
3978       SGPRsUsed.insert(RegSubRegPair(MO->getReg(), MO->getSubReg()));
3979 
3980     for (unsigned i = 0, e = MI.getNumOperands(); i != e; ++i) {
3981       if (i == OpIdx)
3982         continue;
3983       const MachineOperand &Op = MI.getOperand(i);
3984       if (Op.isReg()) {
3985         RegSubRegPair SGPR(Op.getReg(), Op.getSubReg());
3986         if (!SGPRsUsed.count(SGPR) &&
3987             usesConstantBus(MRI, Op, InstDesc.OpInfo[i])) {
3988           if (--ConstantBusLimit <= 0)
3989             return false;
3990           SGPRsUsed.insert(SGPR);
3991         }
3992       } else if (InstDesc.OpInfo[i].OperandType == AMDGPU::OPERAND_KIMM32) {
3993         if (--ConstantBusLimit <= 0)
3994           return false;
3995       } else if (isVOP3(MI) && AMDGPU::isSISrcOperand(InstDesc, i) &&
3996                  isLiteralConstantLike(Op, InstDesc.OpInfo[i])) {
3997         if (!VOP3LiteralLimit--)
3998           return false;
3999         if (--ConstantBusLimit <= 0)
4000           return false;
4001       }
4002     }
4003   }
4004 
4005   if (MO->isReg()) {
4006     assert(DefinedRC);
4007     return isLegalRegOperand(MRI, OpInfo, *MO);
4008   }
4009 
4010   // Handle non-register types that are treated like immediates.
4011   assert(MO->isImm() || MO->isTargetIndex() || MO->isFI() || MO->isGlobal());
4012 
4013   if (!DefinedRC) {
4014     // This operand expects an immediate.
4015     return true;
4016   }
4017 
4018   return isImmOperandLegal(MI, OpIdx, *MO);
4019 }
4020 
legalizeOperandsVOP2(MachineRegisterInfo & MRI,MachineInstr & MI) const4021 void SIInstrInfo::legalizeOperandsVOP2(MachineRegisterInfo &MRI,
4022                                        MachineInstr &MI) const {
4023   unsigned Opc = MI.getOpcode();
4024   const MCInstrDesc &InstrDesc = get(Opc);
4025 
4026   int Src0Idx = AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src0);
4027   MachineOperand &Src0 = MI.getOperand(Src0Idx);
4028 
4029   int Src1Idx = AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src1);
4030   MachineOperand &Src1 = MI.getOperand(Src1Idx);
4031 
4032   // If there is an implicit SGPR use such as VCC use for v_addc_u32/v_subb_u32
4033   // we need to only have one constant bus use before GFX10.
4034   bool HasImplicitSGPR = findImplicitSGPRRead(MI) != AMDGPU::NoRegister;
4035   if (HasImplicitSGPR && ST.getConstantBusLimit(Opc) <= 1 &&
4036       Src0.isReg() && (RI.isSGPRReg(MRI, Src0.getReg()) ||
4037        isLiteralConstantLike(Src0, InstrDesc.OpInfo[Src0Idx])))
4038     legalizeOpWithMove(MI, Src0Idx);
4039 
4040   // Special case: V_WRITELANE_B32 accepts only immediate or SGPR operands for
4041   // both the value to write (src0) and lane select (src1).  Fix up non-SGPR
4042   // src0/src1 with V_READFIRSTLANE.
4043   if (Opc == AMDGPU::V_WRITELANE_B32) {
4044     const DebugLoc &DL = MI.getDebugLoc();
4045     if (Src0.isReg() && RI.isVGPR(MRI, Src0.getReg())) {
4046       Register Reg = MRI.createVirtualRegister(&AMDGPU::SReg_32_XM0RegClass);
4047       BuildMI(*MI.getParent(), MI, DL, get(AMDGPU::V_READFIRSTLANE_B32), Reg)
4048           .add(Src0);
4049       Src0.ChangeToRegister(Reg, false);
4050     }
4051     if (Src1.isReg() && RI.isVGPR(MRI, Src1.getReg())) {
4052       Register Reg = MRI.createVirtualRegister(&AMDGPU::SReg_32_XM0RegClass);
4053       const DebugLoc &DL = MI.getDebugLoc();
4054       BuildMI(*MI.getParent(), MI, DL, get(AMDGPU::V_READFIRSTLANE_B32), Reg)
4055           .add(Src1);
4056       Src1.ChangeToRegister(Reg, false);
4057     }
4058     return;
4059   }
4060 
4061   // No VOP2 instructions support AGPRs.
4062   if (Src0.isReg() && RI.isAGPR(MRI, Src0.getReg()))
4063     legalizeOpWithMove(MI, Src0Idx);
4064 
4065   if (Src1.isReg() && RI.isAGPR(MRI, Src1.getReg()))
4066     legalizeOpWithMove(MI, Src1Idx);
4067 
4068   // VOP2 src0 instructions support all operand types, so we don't need to check
4069   // their legality. If src1 is already legal, we don't need to do anything.
4070   if (isLegalRegOperand(MRI, InstrDesc.OpInfo[Src1Idx], Src1))
4071     return;
4072 
4073   // Special case: V_READLANE_B32 accepts only immediate or SGPR operands for
4074   // lane select. Fix up using V_READFIRSTLANE, since we assume that the lane
4075   // select is uniform.
4076   if (Opc == AMDGPU::V_READLANE_B32 && Src1.isReg() &&
4077       RI.isVGPR(MRI, Src1.getReg())) {
4078     Register Reg = MRI.createVirtualRegister(&AMDGPU::SReg_32_XM0RegClass);
4079     const DebugLoc &DL = MI.getDebugLoc();
4080     BuildMI(*MI.getParent(), MI, DL, get(AMDGPU::V_READFIRSTLANE_B32), Reg)
4081         .add(Src1);
4082     Src1.ChangeToRegister(Reg, false);
4083     return;
4084   }
4085 
4086   // We do not use commuteInstruction here because it is too aggressive and will
4087   // commute if it is possible. We only want to commute here if it improves
4088   // legality. This can be called a fairly large number of times so don't waste
4089   // compile time pointlessly swapping and checking legality again.
4090   if (HasImplicitSGPR || !MI.isCommutable()) {
4091     legalizeOpWithMove(MI, Src1Idx);
4092     return;
4093   }
4094 
4095   // If src0 can be used as src1, commuting will make the operands legal.
4096   // Otherwise we have to give up and insert a move.
4097   //
4098   // TODO: Other immediate-like operand kinds could be commuted if there was a
4099   // MachineOperand::ChangeTo* for them.
4100   if ((!Src1.isImm() && !Src1.isReg()) ||
4101       !isLegalRegOperand(MRI, InstrDesc.OpInfo[Src1Idx], Src0)) {
4102     legalizeOpWithMove(MI, Src1Idx);
4103     return;
4104   }
4105 
4106   int CommutedOpc = commuteOpcode(MI);
4107   if (CommutedOpc == -1) {
4108     legalizeOpWithMove(MI, Src1Idx);
4109     return;
4110   }
4111 
4112   MI.setDesc(get(CommutedOpc));
4113 
4114   Register Src0Reg = Src0.getReg();
4115   unsigned Src0SubReg = Src0.getSubReg();
4116   bool Src0Kill = Src0.isKill();
4117 
4118   if (Src1.isImm())
4119     Src0.ChangeToImmediate(Src1.getImm());
4120   else if (Src1.isReg()) {
4121     Src0.ChangeToRegister(Src1.getReg(), false, false, Src1.isKill());
4122     Src0.setSubReg(Src1.getSubReg());
4123   } else
4124     llvm_unreachable("Should only have register or immediate operands");
4125 
4126   Src1.ChangeToRegister(Src0Reg, false, false, Src0Kill);
4127   Src1.setSubReg(Src0SubReg);
4128   fixImplicitOperands(MI);
4129 }
4130 
4131 // Legalize VOP3 operands. All operand types are supported for any operand
4132 // but only one literal constant and only starting from GFX10.
legalizeOperandsVOP3(MachineRegisterInfo & MRI,MachineInstr & MI) const4133 void SIInstrInfo::legalizeOperandsVOP3(MachineRegisterInfo &MRI,
4134                                        MachineInstr &MI) const {
4135   unsigned Opc = MI.getOpcode();
4136 
4137   int VOP3Idx[3] = {
4138     AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src0),
4139     AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src1),
4140     AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src2)
4141   };
4142 
4143   if (Opc == AMDGPU::V_PERMLANE16_B32 ||
4144       Opc == AMDGPU::V_PERMLANEX16_B32) {
4145     // src1 and src2 must be scalar
4146     MachineOperand &Src1 = MI.getOperand(VOP3Idx[1]);
4147     MachineOperand &Src2 = MI.getOperand(VOP3Idx[2]);
4148     const DebugLoc &DL = MI.getDebugLoc();
4149     if (Src1.isReg() && !RI.isSGPRClass(MRI.getRegClass(Src1.getReg()))) {
4150       Register Reg = MRI.createVirtualRegister(&AMDGPU::SReg_32_XM0RegClass);
4151       BuildMI(*MI.getParent(), MI, DL, get(AMDGPU::V_READFIRSTLANE_B32), Reg)
4152         .add(Src1);
4153       Src1.ChangeToRegister(Reg, false);
4154     }
4155     if (Src2.isReg() && !RI.isSGPRClass(MRI.getRegClass(Src2.getReg()))) {
4156       Register Reg = MRI.createVirtualRegister(&AMDGPU::SReg_32_XM0RegClass);
4157       BuildMI(*MI.getParent(), MI, DL, get(AMDGPU::V_READFIRSTLANE_B32), Reg)
4158         .add(Src2);
4159       Src2.ChangeToRegister(Reg, false);
4160     }
4161   }
4162 
4163   // Find the one SGPR operand we are allowed to use.
4164   int ConstantBusLimit = ST.getConstantBusLimit(Opc);
4165   int LiteralLimit = ST.hasVOP3Literal() ? 1 : 0;
4166   SmallDenseSet<unsigned> SGPRsUsed;
4167   unsigned SGPRReg = findUsedSGPR(MI, VOP3Idx);
4168   if (SGPRReg != AMDGPU::NoRegister) {
4169     SGPRsUsed.insert(SGPRReg);
4170     --ConstantBusLimit;
4171   }
4172 
4173   for (unsigned i = 0; i < 3; ++i) {
4174     int Idx = VOP3Idx[i];
4175     if (Idx == -1)
4176       break;
4177     MachineOperand &MO = MI.getOperand(Idx);
4178 
4179     if (!MO.isReg()) {
4180       if (!isLiteralConstantLike(MO, get(Opc).OpInfo[Idx]))
4181         continue;
4182 
4183       if (LiteralLimit > 0 && ConstantBusLimit > 0) {
4184         --LiteralLimit;
4185         --ConstantBusLimit;
4186         continue;
4187       }
4188 
4189       --LiteralLimit;
4190       --ConstantBusLimit;
4191       legalizeOpWithMove(MI, Idx);
4192       continue;
4193     }
4194 
4195     if (RI.hasAGPRs(MRI.getRegClass(MO.getReg())) &&
4196         !isOperandLegal(MI, Idx, &MO)) {
4197       legalizeOpWithMove(MI, Idx);
4198       continue;
4199     }
4200 
4201     if (!RI.isSGPRClass(MRI.getRegClass(MO.getReg())))
4202       continue; // VGPRs are legal
4203 
4204     // We can use one SGPR in each VOP3 instruction prior to GFX10
4205     // and two starting from GFX10.
4206     if (SGPRsUsed.count(MO.getReg()))
4207       continue;
4208     if (ConstantBusLimit > 0) {
4209       SGPRsUsed.insert(MO.getReg());
4210       --ConstantBusLimit;
4211       continue;
4212     }
4213 
4214     // If we make it this far, then the operand is not legal and we must
4215     // legalize it.
4216     legalizeOpWithMove(MI, Idx);
4217   }
4218 }
4219 
readlaneVGPRToSGPR(unsigned SrcReg,MachineInstr & UseMI,MachineRegisterInfo & MRI) const4220 unsigned SIInstrInfo::readlaneVGPRToSGPR(unsigned SrcReg, MachineInstr &UseMI,
4221                                          MachineRegisterInfo &MRI) const {
4222   const TargetRegisterClass *VRC = MRI.getRegClass(SrcReg);
4223   const TargetRegisterClass *SRC = RI.getEquivalentSGPRClass(VRC);
4224   Register DstReg = MRI.createVirtualRegister(SRC);
4225   unsigned SubRegs = RI.getRegSizeInBits(*VRC) / 32;
4226 
4227   if (RI.hasAGPRs(VRC)) {
4228     VRC = RI.getEquivalentVGPRClass(VRC);
4229     Register NewSrcReg = MRI.createVirtualRegister(VRC);
4230     BuildMI(*UseMI.getParent(), UseMI, UseMI.getDebugLoc(),
4231             get(TargetOpcode::COPY), NewSrcReg)
4232         .addReg(SrcReg);
4233     SrcReg = NewSrcReg;
4234   }
4235 
4236   if (SubRegs == 1) {
4237     BuildMI(*UseMI.getParent(), UseMI, UseMI.getDebugLoc(),
4238             get(AMDGPU::V_READFIRSTLANE_B32), DstReg)
4239         .addReg(SrcReg);
4240     return DstReg;
4241   }
4242 
4243   SmallVector<unsigned, 8> SRegs;
4244   for (unsigned i = 0; i < SubRegs; ++i) {
4245     Register SGPR = MRI.createVirtualRegister(&AMDGPU::SGPR_32RegClass);
4246     BuildMI(*UseMI.getParent(), UseMI, UseMI.getDebugLoc(),
4247             get(AMDGPU::V_READFIRSTLANE_B32), SGPR)
4248         .addReg(SrcReg, 0, RI.getSubRegFromChannel(i));
4249     SRegs.push_back(SGPR);
4250   }
4251 
4252   MachineInstrBuilder MIB =
4253       BuildMI(*UseMI.getParent(), UseMI, UseMI.getDebugLoc(),
4254               get(AMDGPU::REG_SEQUENCE), DstReg);
4255   for (unsigned i = 0; i < SubRegs; ++i) {
4256     MIB.addReg(SRegs[i]);
4257     MIB.addImm(RI.getSubRegFromChannel(i));
4258   }
4259   return DstReg;
4260 }
4261 
legalizeOperandsSMRD(MachineRegisterInfo & MRI,MachineInstr & MI) const4262 void SIInstrInfo::legalizeOperandsSMRD(MachineRegisterInfo &MRI,
4263                                        MachineInstr &MI) const {
4264 
4265   // If the pointer is store in VGPRs, then we need to move them to
4266   // SGPRs using v_readfirstlane.  This is safe because we only select
4267   // loads with uniform pointers to SMRD instruction so we know the
4268   // pointer value is uniform.
4269   MachineOperand *SBase = getNamedOperand(MI, AMDGPU::OpName::sbase);
4270   if (SBase && !RI.isSGPRClass(MRI.getRegClass(SBase->getReg()))) {
4271     unsigned SGPR = readlaneVGPRToSGPR(SBase->getReg(), MI, MRI);
4272     SBase->setReg(SGPR);
4273   }
4274   MachineOperand *SOff = getNamedOperand(MI, AMDGPU::OpName::soff);
4275   if (SOff && !RI.isSGPRClass(MRI.getRegClass(SOff->getReg()))) {
4276     unsigned SGPR = readlaneVGPRToSGPR(SOff->getReg(), MI, MRI);
4277     SOff->setReg(SGPR);
4278   }
4279 }
4280 
legalizeGenericOperand(MachineBasicBlock & InsertMBB,MachineBasicBlock::iterator I,const TargetRegisterClass * DstRC,MachineOperand & Op,MachineRegisterInfo & MRI,const DebugLoc & DL) const4281 void SIInstrInfo::legalizeGenericOperand(MachineBasicBlock &InsertMBB,
4282                                          MachineBasicBlock::iterator I,
4283                                          const TargetRegisterClass *DstRC,
4284                                          MachineOperand &Op,
4285                                          MachineRegisterInfo &MRI,
4286                                          const DebugLoc &DL) const {
4287   Register OpReg = Op.getReg();
4288   unsigned OpSubReg = Op.getSubReg();
4289 
4290   const TargetRegisterClass *OpRC = RI.getSubClassWithSubReg(
4291       RI.getRegClassForReg(MRI, OpReg), OpSubReg);
4292 
4293   // Check if operand is already the correct register class.
4294   if (DstRC == OpRC)
4295     return;
4296 
4297   Register DstReg = MRI.createVirtualRegister(DstRC);
4298   MachineInstr *Copy =
4299       BuildMI(InsertMBB, I, DL, get(AMDGPU::COPY), DstReg).add(Op);
4300 
4301   Op.setReg(DstReg);
4302   Op.setSubReg(0);
4303 
4304   MachineInstr *Def = MRI.getVRegDef(OpReg);
4305   if (!Def)
4306     return;
4307 
4308   // Try to eliminate the copy if it is copying an immediate value.
4309   if (Def->isMoveImmediate() && DstRC != &AMDGPU::VReg_1RegClass)
4310     FoldImmediate(*Copy, *Def, OpReg, &MRI);
4311 
4312   bool ImpDef = Def->isImplicitDef();
4313   while (!ImpDef && Def && Def->isCopy()) {
4314     if (Def->getOperand(1).getReg().isPhysical())
4315       break;
4316     Def = MRI.getUniqueVRegDef(Def->getOperand(1).getReg());
4317     ImpDef = Def && Def->isImplicitDef();
4318   }
4319   if (!RI.isSGPRClass(DstRC) && !Copy->readsRegister(AMDGPU::EXEC, &RI) &&
4320       !ImpDef)
4321     Copy->addOperand(MachineOperand::CreateReg(AMDGPU::EXEC, false, true));
4322 }
4323 
4324 // Emit the actual waterfall loop, executing the wrapped instruction for each
4325 // unique value of \p Rsrc across all lanes. In the best case we execute 1
4326 // iteration, in the worst case we execute 64 (once per lane).
4327 static void
emitLoadSRsrcFromVGPRLoop(const SIInstrInfo & TII,MachineRegisterInfo & MRI,MachineBasicBlock & OrigBB,MachineBasicBlock & LoopBB,const DebugLoc & DL,MachineOperand & Rsrc)4328 emitLoadSRsrcFromVGPRLoop(const SIInstrInfo &TII, MachineRegisterInfo &MRI,
4329                           MachineBasicBlock &OrigBB, MachineBasicBlock &LoopBB,
4330                           const DebugLoc &DL, MachineOperand &Rsrc) {
4331   MachineFunction &MF = *OrigBB.getParent();
4332   const GCNSubtarget &ST = MF.getSubtarget<GCNSubtarget>();
4333   const SIRegisterInfo *TRI = ST.getRegisterInfo();
4334   unsigned Exec = ST.isWave32() ? AMDGPU::EXEC_LO : AMDGPU::EXEC;
4335   unsigned SaveExecOpc =
4336       ST.isWave32() ? AMDGPU::S_AND_SAVEEXEC_B32 : AMDGPU::S_AND_SAVEEXEC_B64;
4337   unsigned XorTermOpc =
4338       ST.isWave32() ? AMDGPU::S_XOR_B32_term : AMDGPU::S_XOR_B64_term;
4339   unsigned AndOpc =
4340       ST.isWave32() ? AMDGPU::S_AND_B32 : AMDGPU::S_AND_B64;
4341   const auto *BoolXExecRC = TRI->getRegClass(AMDGPU::SReg_1_XEXECRegClassID);
4342 
4343   MachineBasicBlock::iterator I = LoopBB.begin();
4344 
4345   Register VRsrc = Rsrc.getReg();
4346   unsigned VRsrcUndef = getUndefRegState(Rsrc.isUndef());
4347 
4348   Register SaveExec = MRI.createVirtualRegister(BoolXExecRC);
4349   Register CondReg0 = MRI.createVirtualRegister(BoolXExecRC);
4350   Register CondReg1 = MRI.createVirtualRegister(BoolXExecRC);
4351   Register AndCond = MRI.createVirtualRegister(BoolXExecRC);
4352   Register SRsrcSub0 = MRI.createVirtualRegister(&AMDGPU::SGPR_32RegClass);
4353   Register SRsrcSub1 = MRI.createVirtualRegister(&AMDGPU::SGPR_32RegClass);
4354   Register SRsrcSub2 = MRI.createVirtualRegister(&AMDGPU::SGPR_32RegClass);
4355   Register SRsrcSub3 = MRI.createVirtualRegister(&AMDGPU::SGPR_32RegClass);
4356   Register SRsrc = MRI.createVirtualRegister(&AMDGPU::SGPR_128RegClass);
4357 
4358   // Beginning of the loop, read the next Rsrc variant.
4359   BuildMI(LoopBB, I, DL, TII.get(AMDGPU::V_READFIRSTLANE_B32), SRsrcSub0)
4360       .addReg(VRsrc, VRsrcUndef, AMDGPU::sub0);
4361   BuildMI(LoopBB, I, DL, TII.get(AMDGPU::V_READFIRSTLANE_B32), SRsrcSub1)
4362       .addReg(VRsrc, VRsrcUndef, AMDGPU::sub1);
4363   BuildMI(LoopBB, I, DL, TII.get(AMDGPU::V_READFIRSTLANE_B32), SRsrcSub2)
4364       .addReg(VRsrc, VRsrcUndef, AMDGPU::sub2);
4365   BuildMI(LoopBB, I, DL, TII.get(AMDGPU::V_READFIRSTLANE_B32), SRsrcSub3)
4366       .addReg(VRsrc, VRsrcUndef, AMDGPU::sub3);
4367 
4368   BuildMI(LoopBB, I, DL, TII.get(AMDGPU::REG_SEQUENCE), SRsrc)
4369       .addReg(SRsrcSub0)
4370       .addImm(AMDGPU::sub0)
4371       .addReg(SRsrcSub1)
4372       .addImm(AMDGPU::sub1)
4373       .addReg(SRsrcSub2)
4374       .addImm(AMDGPU::sub2)
4375       .addReg(SRsrcSub3)
4376       .addImm(AMDGPU::sub3);
4377 
4378   // Update Rsrc operand to use the SGPR Rsrc.
4379   Rsrc.setReg(SRsrc);
4380   Rsrc.setIsKill(true);
4381 
4382   // Identify all lanes with identical Rsrc operands in their VGPRs.
4383   BuildMI(LoopBB, I, DL, TII.get(AMDGPU::V_CMP_EQ_U64_e64), CondReg0)
4384       .addReg(SRsrc, 0, AMDGPU::sub0_sub1)
4385       .addReg(VRsrc, 0, AMDGPU::sub0_sub1);
4386   BuildMI(LoopBB, I, DL, TII.get(AMDGPU::V_CMP_EQ_U64_e64), CondReg1)
4387       .addReg(SRsrc, 0, AMDGPU::sub2_sub3)
4388       .addReg(VRsrc, 0, AMDGPU::sub2_sub3);
4389   BuildMI(LoopBB, I, DL, TII.get(AndOpc), AndCond)
4390       .addReg(CondReg0)
4391       .addReg(CondReg1);
4392 
4393   MRI.setSimpleHint(SaveExec, AndCond);
4394 
4395   // Update EXEC to matching lanes, saving original to SaveExec.
4396   BuildMI(LoopBB, I, DL, TII.get(SaveExecOpc), SaveExec)
4397       .addReg(AndCond, RegState::Kill);
4398 
4399   // The original instruction is here; we insert the terminators after it.
4400   I = LoopBB.end();
4401 
4402   // Update EXEC, switch all done bits to 0 and all todo bits to 1.
4403   BuildMI(LoopBB, I, DL, TII.get(XorTermOpc), Exec)
4404       .addReg(Exec)
4405       .addReg(SaveExec);
4406   BuildMI(LoopBB, I, DL, TII.get(AMDGPU::S_CBRANCH_EXECNZ)).addMBB(&LoopBB);
4407 }
4408 
4409 // Build a waterfall loop around \p MI, replacing the VGPR \p Rsrc register
4410 // with SGPRs by iterating over all unique values across all lanes.
loadSRsrcFromVGPR(const SIInstrInfo & TII,MachineInstr & MI,MachineOperand & Rsrc,MachineDominatorTree * MDT)4411 static void loadSRsrcFromVGPR(const SIInstrInfo &TII, MachineInstr &MI,
4412                               MachineOperand &Rsrc, MachineDominatorTree *MDT) {
4413   MachineBasicBlock &MBB = *MI.getParent();
4414   MachineFunction &MF = *MBB.getParent();
4415   const GCNSubtarget &ST = MF.getSubtarget<GCNSubtarget>();
4416   const SIRegisterInfo *TRI = ST.getRegisterInfo();
4417   MachineRegisterInfo &MRI = MF.getRegInfo();
4418   MachineBasicBlock::iterator I(&MI);
4419   const DebugLoc &DL = MI.getDebugLoc();
4420   unsigned Exec = ST.isWave32() ? AMDGPU::EXEC_LO : AMDGPU::EXEC;
4421   unsigned MovExecOpc = ST.isWave32() ? AMDGPU::S_MOV_B32 : AMDGPU::S_MOV_B64;
4422   const auto *BoolXExecRC = TRI->getRegClass(AMDGPU::SReg_1_XEXECRegClassID);
4423 
4424   Register SaveExec = MRI.createVirtualRegister(BoolXExecRC);
4425 
4426   // Save the EXEC mask
4427   BuildMI(MBB, I, DL, TII.get(MovExecOpc), SaveExec).addReg(Exec);
4428 
4429   // Killed uses in the instruction we are waterfalling around will be
4430   // incorrect due to the added control-flow.
4431   for (auto &MO : MI.uses()) {
4432     if (MO.isReg() && MO.isUse()) {
4433       MRI.clearKillFlags(MO.getReg());
4434     }
4435   }
4436 
4437   // To insert the loop we need to split the block. Move everything after this
4438   // point to a new block, and insert a new empty block between the two.
4439   MachineBasicBlock *LoopBB = MF.CreateMachineBasicBlock();
4440   MachineBasicBlock *RemainderBB = MF.CreateMachineBasicBlock();
4441   MachineFunction::iterator MBBI(MBB);
4442   ++MBBI;
4443 
4444   MF.insert(MBBI, LoopBB);
4445   MF.insert(MBBI, RemainderBB);
4446 
4447   LoopBB->addSuccessor(LoopBB);
4448   LoopBB->addSuccessor(RemainderBB);
4449 
4450   // Move MI to the LoopBB, and the remainder of the block to RemainderBB.
4451   MachineBasicBlock::iterator J = I++;
4452   RemainderBB->transferSuccessorsAndUpdatePHIs(&MBB);
4453   RemainderBB->splice(RemainderBB->begin(), &MBB, I, MBB.end());
4454   LoopBB->splice(LoopBB->begin(), &MBB, J);
4455 
4456   MBB.addSuccessor(LoopBB);
4457 
4458   // Update dominators. We know that MBB immediately dominates LoopBB, that
4459   // LoopBB immediately dominates RemainderBB, and that RemainderBB immediately
4460   // dominates all of the successors transferred to it from MBB that MBB used
4461   // to properly dominate.
4462   if (MDT) {
4463     MDT->addNewBlock(LoopBB, &MBB);
4464     MDT->addNewBlock(RemainderBB, LoopBB);
4465     for (auto &Succ : RemainderBB->successors()) {
4466       if (MDT->properlyDominates(&MBB, Succ)) {
4467         MDT->changeImmediateDominator(Succ, RemainderBB);
4468       }
4469     }
4470   }
4471 
4472   emitLoadSRsrcFromVGPRLoop(TII, MRI, MBB, *LoopBB, DL, Rsrc);
4473 
4474   // Restore the EXEC mask
4475   MachineBasicBlock::iterator First = RemainderBB->begin();
4476   BuildMI(*RemainderBB, First, DL, TII.get(MovExecOpc), Exec).addReg(SaveExec);
4477 }
4478 
4479 // Extract pointer from Rsrc and return a zero-value Rsrc replacement.
4480 static std::tuple<unsigned, unsigned>
extractRsrcPtr(const SIInstrInfo & TII,MachineInstr & MI,MachineOperand & Rsrc)4481 extractRsrcPtr(const SIInstrInfo &TII, MachineInstr &MI, MachineOperand &Rsrc) {
4482   MachineBasicBlock &MBB = *MI.getParent();
4483   MachineFunction &MF = *MBB.getParent();
4484   MachineRegisterInfo &MRI = MF.getRegInfo();
4485 
4486   // Extract the ptr from the resource descriptor.
4487   unsigned RsrcPtr =
4488       TII.buildExtractSubReg(MI, MRI, Rsrc, &AMDGPU::VReg_128RegClass,
4489                              AMDGPU::sub0_sub1, &AMDGPU::VReg_64RegClass);
4490 
4491   // Create an empty resource descriptor
4492   Register Zero64 = MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass);
4493   Register SRsrcFormatLo = MRI.createVirtualRegister(&AMDGPU::SGPR_32RegClass);
4494   Register SRsrcFormatHi = MRI.createVirtualRegister(&AMDGPU::SGPR_32RegClass);
4495   Register NewSRsrc = MRI.createVirtualRegister(&AMDGPU::SGPR_128RegClass);
4496   uint64_t RsrcDataFormat = TII.getDefaultRsrcDataFormat();
4497 
4498   // Zero64 = 0
4499   BuildMI(MBB, MI, MI.getDebugLoc(), TII.get(AMDGPU::S_MOV_B64), Zero64)
4500       .addImm(0);
4501 
4502   // SRsrcFormatLo = RSRC_DATA_FORMAT{31-0}
4503   BuildMI(MBB, MI, MI.getDebugLoc(), TII.get(AMDGPU::S_MOV_B32), SRsrcFormatLo)
4504       .addImm(RsrcDataFormat & 0xFFFFFFFF);
4505 
4506   // SRsrcFormatHi = RSRC_DATA_FORMAT{63-32}
4507   BuildMI(MBB, MI, MI.getDebugLoc(), TII.get(AMDGPU::S_MOV_B32), SRsrcFormatHi)
4508       .addImm(RsrcDataFormat >> 32);
4509 
4510   // NewSRsrc = {Zero64, SRsrcFormat}
4511   BuildMI(MBB, MI, MI.getDebugLoc(), TII.get(AMDGPU::REG_SEQUENCE), NewSRsrc)
4512       .addReg(Zero64)
4513       .addImm(AMDGPU::sub0_sub1)
4514       .addReg(SRsrcFormatLo)
4515       .addImm(AMDGPU::sub2)
4516       .addReg(SRsrcFormatHi)
4517       .addImm(AMDGPU::sub3);
4518 
4519   return std::make_tuple(RsrcPtr, NewSRsrc);
4520 }
4521 
legalizeOperands(MachineInstr & MI,MachineDominatorTree * MDT) const4522 void SIInstrInfo::legalizeOperands(MachineInstr &MI,
4523                                    MachineDominatorTree *MDT) const {
4524   MachineFunction &MF = *MI.getParent()->getParent();
4525   MachineRegisterInfo &MRI = MF.getRegInfo();
4526 
4527   // Legalize VOP2
4528   if (isVOP2(MI) || isVOPC(MI)) {
4529     legalizeOperandsVOP2(MRI, MI);
4530     return;
4531   }
4532 
4533   // Legalize VOP3
4534   if (isVOP3(MI)) {
4535     legalizeOperandsVOP3(MRI, MI);
4536     return;
4537   }
4538 
4539   // Legalize SMRD
4540   if (isSMRD(MI)) {
4541     legalizeOperandsSMRD(MRI, MI);
4542     return;
4543   }
4544 
4545   // Legalize REG_SEQUENCE and PHI
4546   // The register class of the operands much be the same type as the register
4547   // class of the output.
4548   if (MI.getOpcode() == AMDGPU::PHI) {
4549     const TargetRegisterClass *RC = nullptr, *SRC = nullptr, *VRC = nullptr;
4550     for (unsigned i = 1, e = MI.getNumOperands(); i != e; i += 2) {
4551       if (!MI.getOperand(i).isReg() ||
4552           !Register::isVirtualRegister(MI.getOperand(i).getReg()))
4553         continue;
4554       const TargetRegisterClass *OpRC =
4555           MRI.getRegClass(MI.getOperand(i).getReg());
4556       if (RI.hasVectorRegisters(OpRC)) {
4557         VRC = OpRC;
4558       } else {
4559         SRC = OpRC;
4560       }
4561     }
4562 
4563     // If any of the operands are VGPR registers, then they all most be
4564     // otherwise we will create illegal VGPR->SGPR copies when legalizing
4565     // them.
4566     if (VRC || !RI.isSGPRClass(getOpRegClass(MI, 0))) {
4567       if (!VRC) {
4568         assert(SRC);
4569         if (getOpRegClass(MI, 0) == &AMDGPU::VReg_1RegClass) {
4570           VRC = &AMDGPU::VReg_1RegClass;
4571         } else
4572           VRC = RI.hasAGPRs(getOpRegClass(MI, 0))
4573                     ? RI.getEquivalentAGPRClass(SRC)
4574                     : RI.getEquivalentVGPRClass(SRC);
4575       } else {
4576           VRC = RI.hasAGPRs(getOpRegClass(MI, 0))
4577                     ? RI.getEquivalentAGPRClass(VRC)
4578                     : RI.getEquivalentVGPRClass(VRC);
4579       }
4580       RC = VRC;
4581     } else {
4582       RC = SRC;
4583     }
4584 
4585     // Update all the operands so they have the same type.
4586     for (unsigned I = 1, E = MI.getNumOperands(); I != E; I += 2) {
4587       MachineOperand &Op = MI.getOperand(I);
4588       if (!Op.isReg() || !Register::isVirtualRegister(Op.getReg()))
4589         continue;
4590 
4591       // MI is a PHI instruction.
4592       MachineBasicBlock *InsertBB = MI.getOperand(I + 1).getMBB();
4593       MachineBasicBlock::iterator Insert = InsertBB->getFirstTerminator();
4594 
4595       // Avoid creating no-op copies with the same src and dst reg class.  These
4596       // confuse some of the machine passes.
4597       legalizeGenericOperand(*InsertBB, Insert, RC, Op, MRI, MI.getDebugLoc());
4598     }
4599   }
4600 
4601   // REG_SEQUENCE doesn't really require operand legalization, but if one has a
4602   // VGPR dest type and SGPR sources, insert copies so all operands are
4603   // VGPRs. This seems to help operand folding / the register coalescer.
4604   if (MI.getOpcode() == AMDGPU::REG_SEQUENCE) {
4605     MachineBasicBlock *MBB = MI.getParent();
4606     const TargetRegisterClass *DstRC = getOpRegClass(MI, 0);
4607     if (RI.hasVGPRs(DstRC)) {
4608       // Update all the operands so they are VGPR register classes. These may
4609       // not be the same register class because REG_SEQUENCE supports mixing
4610       // subregister index types e.g. sub0_sub1 + sub2 + sub3
4611       for (unsigned I = 1, E = MI.getNumOperands(); I != E; I += 2) {
4612         MachineOperand &Op = MI.getOperand(I);
4613         if (!Op.isReg() || !Register::isVirtualRegister(Op.getReg()))
4614           continue;
4615 
4616         const TargetRegisterClass *OpRC = MRI.getRegClass(Op.getReg());
4617         const TargetRegisterClass *VRC = RI.getEquivalentVGPRClass(OpRC);
4618         if (VRC == OpRC)
4619           continue;
4620 
4621         legalizeGenericOperand(*MBB, MI, VRC, Op, MRI, MI.getDebugLoc());
4622         Op.setIsKill();
4623       }
4624     }
4625 
4626     return;
4627   }
4628 
4629   // Legalize INSERT_SUBREG
4630   // src0 must have the same register class as dst
4631   if (MI.getOpcode() == AMDGPU::INSERT_SUBREG) {
4632     Register Dst = MI.getOperand(0).getReg();
4633     Register Src0 = MI.getOperand(1).getReg();
4634     const TargetRegisterClass *DstRC = MRI.getRegClass(Dst);
4635     const TargetRegisterClass *Src0RC = MRI.getRegClass(Src0);
4636     if (DstRC != Src0RC) {
4637       MachineBasicBlock *MBB = MI.getParent();
4638       MachineOperand &Op = MI.getOperand(1);
4639       legalizeGenericOperand(*MBB, MI, DstRC, Op, MRI, MI.getDebugLoc());
4640     }
4641     return;
4642   }
4643 
4644   // Legalize SI_INIT_M0
4645   if (MI.getOpcode() == AMDGPU::SI_INIT_M0) {
4646     MachineOperand &Src = MI.getOperand(0);
4647     if (Src.isReg() && RI.hasVectorRegisters(MRI.getRegClass(Src.getReg())))
4648       Src.setReg(readlaneVGPRToSGPR(Src.getReg(), MI, MRI));
4649     return;
4650   }
4651 
4652   // Legalize MIMG and MUBUF/MTBUF for shaders.
4653   //
4654   // Shaders only generate MUBUF/MTBUF instructions via intrinsics or via
4655   // scratch memory access. In both cases, the legalization never involves
4656   // conversion to the addr64 form.
4657   if (isMIMG(MI) ||
4658       (AMDGPU::isShader(MF.getFunction().getCallingConv()) &&
4659        (isMUBUF(MI) || isMTBUF(MI)))) {
4660     MachineOperand *SRsrc = getNamedOperand(MI, AMDGPU::OpName::srsrc);
4661     if (SRsrc && !RI.isSGPRClass(MRI.getRegClass(SRsrc->getReg()))) {
4662       unsigned SGPR = readlaneVGPRToSGPR(SRsrc->getReg(), MI, MRI);
4663       SRsrc->setReg(SGPR);
4664     }
4665 
4666     MachineOperand *SSamp = getNamedOperand(MI, AMDGPU::OpName::ssamp);
4667     if (SSamp && !RI.isSGPRClass(MRI.getRegClass(SSamp->getReg()))) {
4668       unsigned SGPR = readlaneVGPRToSGPR(SSamp->getReg(), MI, MRI);
4669       SSamp->setReg(SGPR);
4670     }
4671     return;
4672   }
4673 
4674   // Legalize MUBUF* instructions.
4675   int RsrcIdx =
4676       AMDGPU::getNamedOperandIdx(MI.getOpcode(), AMDGPU::OpName::srsrc);
4677   if (RsrcIdx != -1) {
4678     // We have an MUBUF instruction
4679     MachineOperand *Rsrc = &MI.getOperand(RsrcIdx);
4680     unsigned RsrcRC = get(MI.getOpcode()).OpInfo[RsrcIdx].RegClass;
4681     if (RI.getCommonSubClass(MRI.getRegClass(Rsrc->getReg()),
4682                              RI.getRegClass(RsrcRC))) {
4683       // The operands are legal.
4684       // FIXME: We may need to legalize operands besided srsrc.
4685       return;
4686     }
4687 
4688     // Legalize a VGPR Rsrc.
4689     //
4690     // If the instruction is _ADDR64, we can avoid a waterfall by extracting
4691     // the base pointer from the VGPR Rsrc, adding it to the VAddr, then using
4692     // a zero-value SRsrc.
4693     //
4694     // If the instruction is _OFFSET (both idxen and offen disabled), and we
4695     // support ADDR64 instructions, we can convert to ADDR64 and do the same as
4696     // above.
4697     //
4698     // Otherwise we are on non-ADDR64 hardware, and/or we have
4699     // idxen/offen/bothen and we fall back to a waterfall loop.
4700 
4701     MachineBasicBlock &MBB = *MI.getParent();
4702 
4703     MachineOperand *VAddr = getNamedOperand(MI, AMDGPU::OpName::vaddr);
4704     if (VAddr && AMDGPU::getIfAddr64Inst(MI.getOpcode()) != -1) {
4705       // This is already an ADDR64 instruction so we need to add the pointer
4706       // extracted from the resource descriptor to the current value of VAddr.
4707       Register NewVAddrLo = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
4708       Register NewVAddrHi = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
4709       Register NewVAddr = MRI.createVirtualRegister(&AMDGPU::VReg_64RegClass);
4710 
4711       const auto *BoolXExecRC = RI.getRegClass(AMDGPU::SReg_1_XEXECRegClassID);
4712       Register CondReg0 = MRI.createVirtualRegister(BoolXExecRC);
4713       Register CondReg1 = MRI.createVirtualRegister(BoolXExecRC);
4714 
4715       unsigned RsrcPtr, NewSRsrc;
4716       std::tie(RsrcPtr, NewSRsrc) = extractRsrcPtr(*this, MI, *Rsrc);
4717 
4718       // NewVaddrLo = RsrcPtr:sub0 + VAddr:sub0
4719       const DebugLoc &DL = MI.getDebugLoc();
4720       BuildMI(MBB, MI, DL, get(AMDGPU::V_ADD_I32_e64), NewVAddrLo)
4721         .addDef(CondReg0)
4722         .addReg(RsrcPtr, 0, AMDGPU::sub0)
4723         .addReg(VAddr->getReg(), 0, AMDGPU::sub0)
4724         .addImm(0);
4725 
4726       // NewVaddrHi = RsrcPtr:sub1 + VAddr:sub1
4727       BuildMI(MBB, MI, DL, get(AMDGPU::V_ADDC_U32_e64), NewVAddrHi)
4728         .addDef(CondReg1, RegState::Dead)
4729         .addReg(RsrcPtr, 0, AMDGPU::sub1)
4730         .addReg(VAddr->getReg(), 0, AMDGPU::sub1)
4731         .addReg(CondReg0, RegState::Kill)
4732         .addImm(0);
4733 
4734       // NewVaddr = {NewVaddrHi, NewVaddrLo}
4735       BuildMI(MBB, MI, MI.getDebugLoc(), get(AMDGPU::REG_SEQUENCE), NewVAddr)
4736           .addReg(NewVAddrLo)
4737           .addImm(AMDGPU::sub0)
4738           .addReg(NewVAddrHi)
4739           .addImm(AMDGPU::sub1);
4740 
4741       VAddr->setReg(NewVAddr);
4742       Rsrc->setReg(NewSRsrc);
4743     } else if (!VAddr && ST.hasAddr64()) {
4744       // This instructions is the _OFFSET variant, so we need to convert it to
4745       // ADDR64.
4746       assert(MBB.getParent()->getSubtarget<GCNSubtarget>().getGeneration()
4747              < AMDGPUSubtarget::VOLCANIC_ISLANDS &&
4748              "FIXME: Need to emit flat atomics here");
4749 
4750       unsigned RsrcPtr, NewSRsrc;
4751       std::tie(RsrcPtr, NewSRsrc) = extractRsrcPtr(*this, MI, *Rsrc);
4752 
4753       Register NewVAddr = MRI.createVirtualRegister(&AMDGPU::VReg_64RegClass);
4754       MachineOperand *VData = getNamedOperand(MI, AMDGPU::OpName::vdata);
4755       MachineOperand *Offset = getNamedOperand(MI, AMDGPU::OpName::offset);
4756       MachineOperand *SOffset = getNamedOperand(MI, AMDGPU::OpName::soffset);
4757       unsigned Addr64Opcode = AMDGPU::getAddr64Inst(MI.getOpcode());
4758 
4759       // Atomics rith return have have an additional tied operand and are
4760       // missing some of the special bits.
4761       MachineOperand *VDataIn = getNamedOperand(MI, AMDGPU::OpName::vdata_in);
4762       MachineInstr *Addr64;
4763 
4764       if (!VDataIn) {
4765         // Regular buffer load / store.
4766         MachineInstrBuilder MIB =
4767             BuildMI(MBB, MI, MI.getDebugLoc(), get(Addr64Opcode))
4768                 .add(*VData)
4769                 .addReg(NewVAddr)
4770                 .addReg(NewSRsrc)
4771                 .add(*SOffset)
4772                 .add(*Offset);
4773 
4774         // Atomics do not have this operand.
4775         if (const MachineOperand *GLC =
4776                 getNamedOperand(MI, AMDGPU::OpName::glc)) {
4777           MIB.addImm(GLC->getImm());
4778         }
4779         if (const MachineOperand *DLC =
4780                 getNamedOperand(MI, AMDGPU::OpName::dlc)) {
4781           MIB.addImm(DLC->getImm());
4782         }
4783 
4784         MIB.addImm(getNamedImmOperand(MI, AMDGPU::OpName::slc));
4785 
4786         if (const MachineOperand *TFE =
4787                 getNamedOperand(MI, AMDGPU::OpName::tfe)) {
4788           MIB.addImm(TFE->getImm());
4789         }
4790 
4791         MIB.addImm(getNamedImmOperand(MI, AMDGPU::OpName::swz));
4792 
4793         MIB.cloneMemRefs(MI);
4794         Addr64 = MIB;
4795       } else {
4796         // Atomics with return.
4797         Addr64 = BuildMI(MBB, MI, MI.getDebugLoc(), get(Addr64Opcode))
4798                      .add(*VData)
4799                      .add(*VDataIn)
4800                      .addReg(NewVAddr)
4801                      .addReg(NewSRsrc)
4802                      .add(*SOffset)
4803                      .add(*Offset)
4804                      .addImm(getNamedImmOperand(MI, AMDGPU::OpName::slc))
4805                      .cloneMemRefs(MI);
4806       }
4807 
4808       MI.removeFromParent();
4809 
4810       // NewVaddr = {NewVaddrHi, NewVaddrLo}
4811       BuildMI(MBB, Addr64, Addr64->getDebugLoc(), get(AMDGPU::REG_SEQUENCE),
4812               NewVAddr)
4813           .addReg(RsrcPtr, 0, AMDGPU::sub0)
4814           .addImm(AMDGPU::sub0)
4815           .addReg(RsrcPtr, 0, AMDGPU::sub1)
4816           .addImm(AMDGPU::sub1);
4817     } else {
4818       // This is another variant; legalize Rsrc with waterfall loop from VGPRs
4819       // to SGPRs.
4820       loadSRsrcFromVGPR(*this, MI, *Rsrc, MDT);
4821     }
4822   }
4823 }
4824 
moveToVALU(MachineInstr & TopInst,MachineDominatorTree * MDT) const4825 void SIInstrInfo::moveToVALU(MachineInstr &TopInst,
4826                              MachineDominatorTree *MDT) const {
4827   SetVectorType Worklist;
4828   Worklist.insert(&TopInst);
4829 
4830   while (!Worklist.empty()) {
4831     MachineInstr &Inst = *Worklist.pop_back_val();
4832     MachineBasicBlock *MBB = Inst.getParent();
4833     MachineRegisterInfo &MRI = MBB->getParent()->getRegInfo();
4834 
4835     unsigned Opcode = Inst.getOpcode();
4836     unsigned NewOpcode = getVALUOp(Inst);
4837 
4838     // Handle some special cases
4839     switch (Opcode) {
4840     default:
4841       break;
4842     case AMDGPU::S_ADD_U64_PSEUDO:
4843     case AMDGPU::S_SUB_U64_PSEUDO:
4844       splitScalar64BitAddSub(Worklist, Inst, MDT);
4845       Inst.eraseFromParent();
4846       continue;
4847     case AMDGPU::S_ADD_I32:
4848     case AMDGPU::S_SUB_I32:
4849       // FIXME: The u32 versions currently selected use the carry.
4850       if (moveScalarAddSub(Worklist, Inst, MDT))
4851         continue;
4852 
4853       // Default handling
4854       break;
4855     case AMDGPU::S_AND_B64:
4856       splitScalar64BitBinaryOp(Worklist, Inst, AMDGPU::S_AND_B32, MDT);
4857       Inst.eraseFromParent();
4858       continue;
4859 
4860     case AMDGPU::S_OR_B64:
4861       splitScalar64BitBinaryOp(Worklist, Inst, AMDGPU::S_OR_B32, MDT);
4862       Inst.eraseFromParent();
4863       continue;
4864 
4865     case AMDGPU::S_XOR_B64:
4866       splitScalar64BitBinaryOp(Worklist, Inst, AMDGPU::S_XOR_B32, MDT);
4867       Inst.eraseFromParent();
4868       continue;
4869 
4870     case AMDGPU::S_NAND_B64:
4871       splitScalar64BitBinaryOp(Worklist, Inst, AMDGPU::S_NAND_B32, MDT);
4872       Inst.eraseFromParent();
4873       continue;
4874 
4875     case AMDGPU::S_NOR_B64:
4876       splitScalar64BitBinaryOp(Worklist, Inst, AMDGPU::S_NOR_B32, MDT);
4877       Inst.eraseFromParent();
4878       continue;
4879 
4880     case AMDGPU::S_XNOR_B64:
4881       if (ST.hasDLInsts())
4882         splitScalar64BitBinaryOp(Worklist, Inst, AMDGPU::S_XNOR_B32, MDT);
4883       else
4884         splitScalar64BitXnor(Worklist, Inst, MDT);
4885       Inst.eraseFromParent();
4886       continue;
4887 
4888     case AMDGPU::S_ANDN2_B64:
4889       splitScalar64BitBinaryOp(Worklist, Inst, AMDGPU::S_ANDN2_B32, MDT);
4890       Inst.eraseFromParent();
4891       continue;
4892 
4893     case AMDGPU::S_ORN2_B64:
4894       splitScalar64BitBinaryOp(Worklist, Inst, AMDGPU::S_ORN2_B32, MDT);
4895       Inst.eraseFromParent();
4896       continue;
4897 
4898     case AMDGPU::S_NOT_B64:
4899       splitScalar64BitUnaryOp(Worklist, Inst, AMDGPU::S_NOT_B32);
4900       Inst.eraseFromParent();
4901       continue;
4902 
4903     case AMDGPU::S_BCNT1_I32_B64:
4904       splitScalar64BitBCNT(Worklist, Inst);
4905       Inst.eraseFromParent();
4906       continue;
4907 
4908     case AMDGPU::S_BFE_I64:
4909       splitScalar64BitBFE(Worklist, Inst);
4910       Inst.eraseFromParent();
4911       continue;
4912 
4913     case AMDGPU::S_LSHL_B32:
4914       if (ST.hasOnlyRevVALUShifts()) {
4915         NewOpcode = AMDGPU::V_LSHLREV_B32_e64;
4916         swapOperands(Inst);
4917       }
4918       break;
4919     case AMDGPU::S_ASHR_I32:
4920       if (ST.hasOnlyRevVALUShifts()) {
4921         NewOpcode = AMDGPU::V_ASHRREV_I32_e64;
4922         swapOperands(Inst);
4923       }
4924       break;
4925     case AMDGPU::S_LSHR_B32:
4926       if (ST.hasOnlyRevVALUShifts()) {
4927         NewOpcode = AMDGPU::V_LSHRREV_B32_e64;
4928         swapOperands(Inst);
4929       }
4930       break;
4931     case AMDGPU::S_LSHL_B64:
4932       if (ST.hasOnlyRevVALUShifts()) {
4933         NewOpcode = AMDGPU::V_LSHLREV_B64;
4934         swapOperands(Inst);
4935       }
4936       break;
4937     case AMDGPU::S_ASHR_I64:
4938       if (ST.hasOnlyRevVALUShifts()) {
4939         NewOpcode = AMDGPU::V_ASHRREV_I64;
4940         swapOperands(Inst);
4941       }
4942       break;
4943     case AMDGPU::S_LSHR_B64:
4944       if (ST.hasOnlyRevVALUShifts()) {
4945         NewOpcode = AMDGPU::V_LSHRREV_B64;
4946         swapOperands(Inst);
4947       }
4948       break;
4949 
4950     case AMDGPU::S_ABS_I32:
4951       lowerScalarAbs(Worklist, Inst);
4952       Inst.eraseFromParent();
4953       continue;
4954 
4955     case AMDGPU::S_CBRANCH_SCC0:
4956     case AMDGPU::S_CBRANCH_SCC1:
4957       // Clear unused bits of vcc
4958       if (ST.isWave32())
4959         BuildMI(*MBB, Inst, Inst.getDebugLoc(), get(AMDGPU::S_AND_B32),
4960                 AMDGPU::VCC_LO)
4961             .addReg(AMDGPU::EXEC_LO)
4962             .addReg(AMDGPU::VCC_LO);
4963       else
4964         BuildMI(*MBB, Inst, Inst.getDebugLoc(), get(AMDGPU::S_AND_B64),
4965                 AMDGPU::VCC)
4966             .addReg(AMDGPU::EXEC)
4967             .addReg(AMDGPU::VCC);
4968       break;
4969 
4970     case AMDGPU::S_BFE_U64:
4971     case AMDGPU::S_BFM_B64:
4972       llvm_unreachable("Moving this op to VALU not implemented");
4973 
4974     case AMDGPU::S_PACK_LL_B32_B16:
4975     case AMDGPU::S_PACK_LH_B32_B16:
4976     case AMDGPU::S_PACK_HH_B32_B16:
4977       movePackToVALU(Worklist, MRI, Inst);
4978       Inst.eraseFromParent();
4979       continue;
4980 
4981     case AMDGPU::S_XNOR_B32:
4982       lowerScalarXnor(Worklist, Inst);
4983       Inst.eraseFromParent();
4984       continue;
4985 
4986     case AMDGPU::S_NAND_B32:
4987       splitScalarNotBinop(Worklist, Inst, AMDGPU::S_AND_B32);
4988       Inst.eraseFromParent();
4989       continue;
4990 
4991     case AMDGPU::S_NOR_B32:
4992       splitScalarNotBinop(Worklist, Inst, AMDGPU::S_OR_B32);
4993       Inst.eraseFromParent();
4994       continue;
4995 
4996     case AMDGPU::S_ANDN2_B32:
4997       splitScalarBinOpN2(Worklist, Inst, AMDGPU::S_AND_B32);
4998       Inst.eraseFromParent();
4999       continue;
5000 
5001     case AMDGPU::S_ORN2_B32:
5002       splitScalarBinOpN2(Worklist, Inst, AMDGPU::S_OR_B32);
5003       Inst.eraseFromParent();
5004       continue;
5005     }
5006 
5007     if (NewOpcode == AMDGPU::INSTRUCTION_LIST_END) {
5008       // We cannot move this instruction to the VALU, so we should try to
5009       // legalize its operands instead.
5010       legalizeOperands(Inst, MDT);
5011       continue;
5012     }
5013 
5014     // Use the new VALU Opcode.
5015     const MCInstrDesc &NewDesc = get(NewOpcode);
5016     Inst.setDesc(NewDesc);
5017 
5018     // Remove any references to SCC. Vector instructions can't read from it, and
5019     // We're just about to add the implicit use / defs of VCC, and we don't want
5020     // both.
5021     for (unsigned i = Inst.getNumOperands() - 1; i > 0; --i) {
5022       MachineOperand &Op = Inst.getOperand(i);
5023       if (Op.isReg() && Op.getReg() == AMDGPU::SCC) {
5024         // Only propagate through live-def of SCC.
5025         if (Op.isDef() && !Op.isDead())
5026           addSCCDefUsersToVALUWorklist(Op, Inst, Worklist);
5027         Inst.RemoveOperand(i);
5028       }
5029     }
5030 
5031     if (Opcode == AMDGPU::S_SEXT_I32_I8 || Opcode == AMDGPU::S_SEXT_I32_I16) {
5032       // We are converting these to a BFE, so we need to add the missing
5033       // operands for the size and offset.
5034       unsigned Size = (Opcode == AMDGPU::S_SEXT_I32_I8) ? 8 : 16;
5035       Inst.addOperand(MachineOperand::CreateImm(0));
5036       Inst.addOperand(MachineOperand::CreateImm(Size));
5037 
5038     } else if (Opcode == AMDGPU::S_BCNT1_I32_B32) {
5039       // The VALU version adds the second operand to the result, so insert an
5040       // extra 0 operand.
5041       Inst.addOperand(MachineOperand::CreateImm(0));
5042     }
5043 
5044     Inst.addImplicitDefUseOperands(*Inst.getParent()->getParent());
5045     fixImplicitOperands(Inst);
5046 
5047     if (Opcode == AMDGPU::S_BFE_I32 || Opcode == AMDGPU::S_BFE_U32) {
5048       const MachineOperand &OffsetWidthOp = Inst.getOperand(2);
5049       // If we need to move this to VGPRs, we need to unpack the second operand
5050       // back into the 2 separate ones for bit offset and width.
5051       assert(OffsetWidthOp.isImm() &&
5052              "Scalar BFE is only implemented for constant width and offset");
5053       uint32_t Imm = OffsetWidthOp.getImm();
5054 
5055       uint32_t Offset = Imm & 0x3f; // Extract bits [5:0].
5056       uint32_t BitWidth = (Imm & 0x7f0000) >> 16; // Extract bits [22:16].
5057       Inst.RemoveOperand(2);                     // Remove old immediate.
5058       Inst.addOperand(MachineOperand::CreateImm(Offset));
5059       Inst.addOperand(MachineOperand::CreateImm(BitWidth));
5060     }
5061 
5062     bool HasDst = Inst.getOperand(0).isReg() && Inst.getOperand(0).isDef();
5063     unsigned NewDstReg = AMDGPU::NoRegister;
5064     if (HasDst) {
5065       Register DstReg = Inst.getOperand(0).getReg();
5066       if (Register::isPhysicalRegister(DstReg))
5067         continue;
5068 
5069       // Update the destination register class.
5070       const TargetRegisterClass *NewDstRC = getDestEquivalentVGPRClass(Inst);
5071       if (!NewDstRC)
5072         continue;
5073 
5074       if (Inst.isCopy() &&
5075           Register::isVirtualRegister(Inst.getOperand(1).getReg()) &&
5076           NewDstRC == RI.getRegClassForReg(MRI, Inst.getOperand(1).getReg())) {
5077         // Instead of creating a copy where src and dst are the same register
5078         // class, we just replace all uses of dst with src.  These kinds of
5079         // copies interfere with the heuristics MachineSink uses to decide
5080         // whether or not to split a critical edge.  Since the pass assumes
5081         // that copies will end up as machine instructions and not be
5082         // eliminated.
5083         addUsersToMoveToVALUWorklist(DstReg, MRI, Worklist);
5084         MRI.replaceRegWith(DstReg, Inst.getOperand(1).getReg());
5085         MRI.clearKillFlags(Inst.getOperand(1).getReg());
5086         Inst.getOperand(0).setReg(DstReg);
5087 
5088         // Make sure we don't leave around a dead VGPR->SGPR copy. Normally
5089         // these are deleted later, but at -O0 it would leave a suspicious
5090         // looking illegal copy of an undef register.
5091         for (unsigned I = Inst.getNumOperands() - 1; I != 0; --I)
5092           Inst.RemoveOperand(I);
5093         Inst.setDesc(get(AMDGPU::IMPLICIT_DEF));
5094         continue;
5095       }
5096 
5097       NewDstReg = MRI.createVirtualRegister(NewDstRC);
5098       MRI.replaceRegWith(DstReg, NewDstReg);
5099     }
5100 
5101     // Legalize the operands
5102     legalizeOperands(Inst, MDT);
5103 
5104     if (HasDst)
5105      addUsersToMoveToVALUWorklist(NewDstReg, MRI, Worklist);
5106   }
5107 }
5108 
5109 // Add/sub require special handling to deal with carry outs.
moveScalarAddSub(SetVectorType & Worklist,MachineInstr & Inst,MachineDominatorTree * MDT) const5110 bool SIInstrInfo::moveScalarAddSub(SetVectorType &Worklist, MachineInstr &Inst,
5111                                    MachineDominatorTree *MDT) const {
5112   if (ST.hasAddNoCarry()) {
5113     // Assume there is no user of scc since we don't select this in that case.
5114     // Since scc isn't used, it doesn't really matter if the i32 or u32 variant
5115     // is used.
5116 
5117     MachineBasicBlock &MBB = *Inst.getParent();
5118     MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
5119 
5120     Register OldDstReg = Inst.getOperand(0).getReg();
5121     Register ResultReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5122 
5123     unsigned Opc = Inst.getOpcode();
5124     assert(Opc == AMDGPU::S_ADD_I32 || Opc == AMDGPU::S_SUB_I32);
5125 
5126     unsigned NewOpc = Opc == AMDGPU::S_ADD_I32 ?
5127       AMDGPU::V_ADD_U32_e64 : AMDGPU::V_SUB_U32_e64;
5128 
5129     assert(Inst.getOperand(3).getReg() == AMDGPU::SCC);
5130     Inst.RemoveOperand(3);
5131 
5132     Inst.setDesc(get(NewOpc));
5133     Inst.addOperand(MachineOperand::CreateImm(0)); // clamp bit
5134     Inst.addImplicitDefUseOperands(*MBB.getParent());
5135     MRI.replaceRegWith(OldDstReg, ResultReg);
5136     legalizeOperands(Inst, MDT);
5137 
5138     addUsersToMoveToVALUWorklist(ResultReg, MRI, Worklist);
5139     return true;
5140   }
5141 
5142   return false;
5143 }
5144 
lowerScalarAbs(SetVectorType & Worklist,MachineInstr & Inst) const5145 void SIInstrInfo::lowerScalarAbs(SetVectorType &Worklist,
5146                                  MachineInstr &Inst) const {
5147   MachineBasicBlock &MBB = *Inst.getParent();
5148   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
5149   MachineBasicBlock::iterator MII = Inst;
5150   DebugLoc DL = Inst.getDebugLoc();
5151 
5152   MachineOperand &Dest = Inst.getOperand(0);
5153   MachineOperand &Src = Inst.getOperand(1);
5154   Register TmpReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5155   Register ResultReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5156 
5157   unsigned SubOp = ST.hasAddNoCarry() ?
5158     AMDGPU::V_SUB_U32_e32 : AMDGPU::V_SUB_I32_e32;
5159 
5160   BuildMI(MBB, MII, DL, get(SubOp), TmpReg)
5161     .addImm(0)
5162     .addReg(Src.getReg());
5163 
5164   BuildMI(MBB, MII, DL, get(AMDGPU::V_MAX_I32_e64), ResultReg)
5165     .addReg(Src.getReg())
5166     .addReg(TmpReg);
5167 
5168   MRI.replaceRegWith(Dest.getReg(), ResultReg);
5169   addUsersToMoveToVALUWorklist(ResultReg, MRI, Worklist);
5170 }
5171 
lowerScalarXnor(SetVectorType & Worklist,MachineInstr & Inst) const5172 void SIInstrInfo::lowerScalarXnor(SetVectorType &Worklist,
5173                                   MachineInstr &Inst) const {
5174   MachineBasicBlock &MBB = *Inst.getParent();
5175   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
5176   MachineBasicBlock::iterator MII = Inst;
5177   const DebugLoc &DL = Inst.getDebugLoc();
5178 
5179   MachineOperand &Dest = Inst.getOperand(0);
5180   MachineOperand &Src0 = Inst.getOperand(1);
5181   MachineOperand &Src1 = Inst.getOperand(2);
5182 
5183   if (ST.hasDLInsts()) {
5184     Register NewDest = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5185     legalizeGenericOperand(MBB, MII, &AMDGPU::VGPR_32RegClass, Src0, MRI, DL);
5186     legalizeGenericOperand(MBB, MII, &AMDGPU::VGPR_32RegClass, Src1, MRI, DL);
5187 
5188     BuildMI(MBB, MII, DL, get(AMDGPU::V_XNOR_B32_e64), NewDest)
5189       .add(Src0)
5190       .add(Src1);
5191 
5192     MRI.replaceRegWith(Dest.getReg(), NewDest);
5193     addUsersToMoveToVALUWorklist(NewDest, MRI, Worklist);
5194   } else {
5195     // Using the identity !(x ^ y) == (!x ^ y) == (x ^ !y), we can
5196     // invert either source and then perform the XOR. If either source is a
5197     // scalar register, then we can leave the inversion on the scalar unit to
5198     // acheive a better distrubution of scalar and vector instructions.
5199     bool Src0IsSGPR = Src0.isReg() &&
5200                       RI.isSGPRClass(MRI.getRegClass(Src0.getReg()));
5201     bool Src1IsSGPR = Src1.isReg() &&
5202                       RI.isSGPRClass(MRI.getRegClass(Src1.getReg()));
5203     MachineInstr *Xor;
5204     Register Temp = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
5205     Register NewDest = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
5206 
5207     // Build a pair of scalar instructions and add them to the work list.
5208     // The next iteration over the work list will lower these to the vector
5209     // unit as necessary.
5210     if (Src0IsSGPR) {
5211       BuildMI(MBB, MII, DL, get(AMDGPU::S_NOT_B32), Temp).add(Src0);
5212       Xor = BuildMI(MBB, MII, DL, get(AMDGPU::S_XOR_B32), NewDest)
5213       .addReg(Temp)
5214       .add(Src1);
5215     } else if (Src1IsSGPR) {
5216       BuildMI(MBB, MII, DL, get(AMDGPU::S_NOT_B32), Temp).add(Src1);
5217       Xor = BuildMI(MBB, MII, DL, get(AMDGPU::S_XOR_B32), NewDest)
5218       .add(Src0)
5219       .addReg(Temp);
5220     } else {
5221       Xor = BuildMI(MBB, MII, DL, get(AMDGPU::S_XOR_B32), Temp)
5222         .add(Src0)
5223         .add(Src1);
5224       MachineInstr *Not =
5225           BuildMI(MBB, MII, DL, get(AMDGPU::S_NOT_B32), NewDest).addReg(Temp);
5226       Worklist.insert(Not);
5227     }
5228 
5229     MRI.replaceRegWith(Dest.getReg(), NewDest);
5230 
5231     Worklist.insert(Xor);
5232 
5233     addUsersToMoveToVALUWorklist(NewDest, MRI, Worklist);
5234   }
5235 }
5236 
splitScalarNotBinop(SetVectorType & Worklist,MachineInstr & Inst,unsigned Opcode) const5237 void SIInstrInfo::splitScalarNotBinop(SetVectorType &Worklist,
5238                                       MachineInstr &Inst,
5239                                       unsigned Opcode) const {
5240   MachineBasicBlock &MBB = *Inst.getParent();
5241   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
5242   MachineBasicBlock::iterator MII = Inst;
5243   const DebugLoc &DL = Inst.getDebugLoc();
5244 
5245   MachineOperand &Dest = Inst.getOperand(0);
5246   MachineOperand &Src0 = Inst.getOperand(1);
5247   MachineOperand &Src1 = Inst.getOperand(2);
5248 
5249   Register NewDest = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
5250   Register Interm = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
5251 
5252   MachineInstr &Op = *BuildMI(MBB, MII, DL, get(Opcode), Interm)
5253     .add(Src0)
5254     .add(Src1);
5255 
5256   MachineInstr &Not = *BuildMI(MBB, MII, DL, get(AMDGPU::S_NOT_B32), NewDest)
5257     .addReg(Interm);
5258 
5259   Worklist.insert(&Op);
5260   Worklist.insert(&Not);
5261 
5262   MRI.replaceRegWith(Dest.getReg(), NewDest);
5263   addUsersToMoveToVALUWorklist(NewDest, MRI, Worklist);
5264 }
5265 
splitScalarBinOpN2(SetVectorType & Worklist,MachineInstr & Inst,unsigned Opcode) const5266 void SIInstrInfo::splitScalarBinOpN2(SetVectorType& Worklist,
5267                                      MachineInstr &Inst,
5268                                      unsigned Opcode) const {
5269   MachineBasicBlock &MBB = *Inst.getParent();
5270   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
5271   MachineBasicBlock::iterator MII = Inst;
5272   const DebugLoc &DL = Inst.getDebugLoc();
5273 
5274   MachineOperand &Dest = Inst.getOperand(0);
5275   MachineOperand &Src0 = Inst.getOperand(1);
5276   MachineOperand &Src1 = Inst.getOperand(2);
5277 
5278   Register NewDest = MRI.createVirtualRegister(&AMDGPU::SReg_32_XM0RegClass);
5279   Register Interm = MRI.createVirtualRegister(&AMDGPU::SReg_32_XM0RegClass);
5280 
5281   MachineInstr &Not = *BuildMI(MBB, MII, DL, get(AMDGPU::S_NOT_B32), Interm)
5282     .add(Src1);
5283 
5284   MachineInstr &Op = *BuildMI(MBB, MII, DL, get(Opcode), NewDest)
5285     .add(Src0)
5286     .addReg(Interm);
5287 
5288   Worklist.insert(&Not);
5289   Worklist.insert(&Op);
5290 
5291   MRI.replaceRegWith(Dest.getReg(), NewDest);
5292   addUsersToMoveToVALUWorklist(NewDest, MRI, Worklist);
5293 }
5294 
splitScalar64BitUnaryOp(SetVectorType & Worklist,MachineInstr & Inst,unsigned Opcode) const5295 void SIInstrInfo::splitScalar64BitUnaryOp(
5296     SetVectorType &Worklist, MachineInstr &Inst,
5297     unsigned Opcode) const {
5298   MachineBasicBlock &MBB = *Inst.getParent();
5299   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
5300 
5301   MachineOperand &Dest = Inst.getOperand(0);
5302   MachineOperand &Src0 = Inst.getOperand(1);
5303   DebugLoc DL = Inst.getDebugLoc();
5304 
5305   MachineBasicBlock::iterator MII = Inst;
5306 
5307   const MCInstrDesc &InstDesc = get(Opcode);
5308   const TargetRegisterClass *Src0RC = Src0.isReg() ?
5309     MRI.getRegClass(Src0.getReg()) :
5310     &AMDGPU::SGPR_32RegClass;
5311 
5312   const TargetRegisterClass *Src0SubRC = RI.getSubRegClass(Src0RC, AMDGPU::sub0);
5313 
5314   MachineOperand SrcReg0Sub0 = buildExtractSubRegOrImm(MII, MRI, Src0, Src0RC,
5315                                                        AMDGPU::sub0, Src0SubRC);
5316 
5317   const TargetRegisterClass *DestRC = MRI.getRegClass(Dest.getReg());
5318   const TargetRegisterClass *NewDestRC = RI.getEquivalentVGPRClass(DestRC);
5319   const TargetRegisterClass *NewDestSubRC = RI.getSubRegClass(NewDestRC, AMDGPU::sub0);
5320 
5321   Register DestSub0 = MRI.createVirtualRegister(NewDestSubRC);
5322   MachineInstr &LoHalf = *BuildMI(MBB, MII, DL, InstDesc, DestSub0).add(SrcReg0Sub0);
5323 
5324   MachineOperand SrcReg0Sub1 = buildExtractSubRegOrImm(MII, MRI, Src0, Src0RC,
5325                                                        AMDGPU::sub1, Src0SubRC);
5326 
5327   Register DestSub1 = MRI.createVirtualRegister(NewDestSubRC);
5328   MachineInstr &HiHalf = *BuildMI(MBB, MII, DL, InstDesc, DestSub1).add(SrcReg0Sub1);
5329 
5330   Register FullDestReg = MRI.createVirtualRegister(NewDestRC);
5331   BuildMI(MBB, MII, DL, get(TargetOpcode::REG_SEQUENCE), FullDestReg)
5332     .addReg(DestSub0)
5333     .addImm(AMDGPU::sub0)
5334     .addReg(DestSub1)
5335     .addImm(AMDGPU::sub1);
5336 
5337   MRI.replaceRegWith(Dest.getReg(), FullDestReg);
5338 
5339   Worklist.insert(&LoHalf);
5340   Worklist.insert(&HiHalf);
5341 
5342   // We don't need to legalizeOperands here because for a single operand, src0
5343   // will support any kind of input.
5344 
5345   // Move all users of this moved value.
5346   addUsersToMoveToVALUWorklist(FullDestReg, MRI, Worklist);
5347 }
5348 
splitScalar64BitAddSub(SetVectorType & Worklist,MachineInstr & Inst,MachineDominatorTree * MDT) const5349 void SIInstrInfo::splitScalar64BitAddSub(SetVectorType &Worklist,
5350                                          MachineInstr &Inst,
5351                                          MachineDominatorTree *MDT) const {
5352   bool IsAdd = (Inst.getOpcode() == AMDGPU::S_ADD_U64_PSEUDO);
5353 
5354   MachineBasicBlock &MBB = *Inst.getParent();
5355   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
5356   const auto *CarryRC = RI.getRegClass(AMDGPU::SReg_1_XEXECRegClassID);
5357 
5358   Register FullDestReg = MRI.createVirtualRegister(&AMDGPU::VReg_64RegClass);
5359   Register DestSub0 = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5360   Register DestSub1 = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5361 
5362   Register CarryReg = MRI.createVirtualRegister(CarryRC);
5363   Register DeadCarryReg = MRI.createVirtualRegister(CarryRC);
5364 
5365   MachineOperand &Dest = Inst.getOperand(0);
5366   MachineOperand &Src0 = Inst.getOperand(1);
5367   MachineOperand &Src1 = Inst.getOperand(2);
5368   const DebugLoc &DL = Inst.getDebugLoc();
5369   MachineBasicBlock::iterator MII = Inst;
5370 
5371   const TargetRegisterClass *Src0RC = MRI.getRegClass(Src0.getReg());
5372   const TargetRegisterClass *Src1RC = MRI.getRegClass(Src1.getReg());
5373   const TargetRegisterClass *Src0SubRC = RI.getSubRegClass(Src0RC, AMDGPU::sub0);
5374   const TargetRegisterClass *Src1SubRC = RI.getSubRegClass(Src1RC, AMDGPU::sub0);
5375 
5376   MachineOperand SrcReg0Sub0 = buildExtractSubRegOrImm(MII, MRI, Src0, Src0RC,
5377                                                        AMDGPU::sub0, Src0SubRC);
5378   MachineOperand SrcReg1Sub0 = buildExtractSubRegOrImm(MII, MRI, Src1, Src1RC,
5379                                                        AMDGPU::sub0, Src1SubRC);
5380 
5381 
5382   MachineOperand SrcReg0Sub1 = buildExtractSubRegOrImm(MII, MRI, Src0, Src0RC,
5383                                                        AMDGPU::sub1, Src0SubRC);
5384   MachineOperand SrcReg1Sub1 = buildExtractSubRegOrImm(MII, MRI, Src1, Src1RC,
5385                                                        AMDGPU::sub1, Src1SubRC);
5386 
5387   unsigned LoOpc = IsAdd ? AMDGPU::V_ADD_I32_e64 : AMDGPU::V_SUB_I32_e64;
5388   MachineInstr *LoHalf =
5389     BuildMI(MBB, MII, DL, get(LoOpc), DestSub0)
5390     .addReg(CarryReg, RegState::Define)
5391     .add(SrcReg0Sub0)
5392     .add(SrcReg1Sub0)
5393     .addImm(0); // clamp bit
5394 
5395   unsigned HiOpc = IsAdd ? AMDGPU::V_ADDC_U32_e64 : AMDGPU::V_SUBB_U32_e64;
5396   MachineInstr *HiHalf =
5397     BuildMI(MBB, MII, DL, get(HiOpc), DestSub1)
5398     .addReg(DeadCarryReg, RegState::Define | RegState::Dead)
5399     .add(SrcReg0Sub1)
5400     .add(SrcReg1Sub1)
5401     .addReg(CarryReg, RegState::Kill)
5402     .addImm(0); // clamp bit
5403 
5404   BuildMI(MBB, MII, DL, get(TargetOpcode::REG_SEQUENCE), FullDestReg)
5405     .addReg(DestSub0)
5406     .addImm(AMDGPU::sub0)
5407     .addReg(DestSub1)
5408     .addImm(AMDGPU::sub1);
5409 
5410   MRI.replaceRegWith(Dest.getReg(), FullDestReg);
5411 
5412   // Try to legalize the operands in case we need to swap the order to keep it
5413   // valid.
5414   legalizeOperands(*LoHalf, MDT);
5415   legalizeOperands(*HiHalf, MDT);
5416 
5417   // Move all users of this moved vlaue.
5418   addUsersToMoveToVALUWorklist(FullDestReg, MRI, Worklist);
5419 }
5420 
splitScalar64BitBinaryOp(SetVectorType & Worklist,MachineInstr & Inst,unsigned Opcode,MachineDominatorTree * MDT) const5421 void SIInstrInfo::splitScalar64BitBinaryOp(SetVectorType &Worklist,
5422                                            MachineInstr &Inst, unsigned Opcode,
5423                                            MachineDominatorTree *MDT) const {
5424   MachineBasicBlock &MBB = *Inst.getParent();
5425   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
5426 
5427   MachineOperand &Dest = Inst.getOperand(0);
5428   MachineOperand &Src0 = Inst.getOperand(1);
5429   MachineOperand &Src1 = Inst.getOperand(2);
5430   DebugLoc DL = Inst.getDebugLoc();
5431 
5432   MachineBasicBlock::iterator MII = Inst;
5433 
5434   const MCInstrDesc &InstDesc = get(Opcode);
5435   const TargetRegisterClass *Src0RC = Src0.isReg() ?
5436     MRI.getRegClass(Src0.getReg()) :
5437     &AMDGPU::SGPR_32RegClass;
5438 
5439   const TargetRegisterClass *Src0SubRC = RI.getSubRegClass(Src0RC, AMDGPU::sub0);
5440   const TargetRegisterClass *Src1RC = Src1.isReg() ?
5441     MRI.getRegClass(Src1.getReg()) :
5442     &AMDGPU::SGPR_32RegClass;
5443 
5444   const TargetRegisterClass *Src1SubRC = RI.getSubRegClass(Src1RC, AMDGPU::sub0);
5445 
5446   MachineOperand SrcReg0Sub0 = buildExtractSubRegOrImm(MII, MRI, Src0, Src0RC,
5447                                                        AMDGPU::sub0, Src0SubRC);
5448   MachineOperand SrcReg1Sub0 = buildExtractSubRegOrImm(MII, MRI, Src1, Src1RC,
5449                                                        AMDGPU::sub0, Src1SubRC);
5450   MachineOperand SrcReg0Sub1 = buildExtractSubRegOrImm(MII, MRI, Src0, Src0RC,
5451                                                        AMDGPU::sub1, Src0SubRC);
5452   MachineOperand SrcReg1Sub1 = buildExtractSubRegOrImm(MII, MRI, Src1, Src1RC,
5453                                                        AMDGPU::sub1, Src1SubRC);
5454 
5455   const TargetRegisterClass *DestRC = MRI.getRegClass(Dest.getReg());
5456   const TargetRegisterClass *NewDestRC = RI.getEquivalentVGPRClass(DestRC);
5457   const TargetRegisterClass *NewDestSubRC = RI.getSubRegClass(NewDestRC, AMDGPU::sub0);
5458 
5459   Register DestSub0 = MRI.createVirtualRegister(NewDestSubRC);
5460   MachineInstr &LoHalf = *BuildMI(MBB, MII, DL, InstDesc, DestSub0)
5461                               .add(SrcReg0Sub0)
5462                               .add(SrcReg1Sub0);
5463 
5464   Register DestSub1 = MRI.createVirtualRegister(NewDestSubRC);
5465   MachineInstr &HiHalf = *BuildMI(MBB, MII, DL, InstDesc, DestSub1)
5466                               .add(SrcReg0Sub1)
5467                               .add(SrcReg1Sub1);
5468 
5469   Register FullDestReg = MRI.createVirtualRegister(NewDestRC);
5470   BuildMI(MBB, MII, DL, get(TargetOpcode::REG_SEQUENCE), FullDestReg)
5471     .addReg(DestSub0)
5472     .addImm(AMDGPU::sub0)
5473     .addReg(DestSub1)
5474     .addImm(AMDGPU::sub1);
5475 
5476   MRI.replaceRegWith(Dest.getReg(), FullDestReg);
5477 
5478   Worklist.insert(&LoHalf);
5479   Worklist.insert(&HiHalf);
5480 
5481   // Move all users of this moved vlaue.
5482   addUsersToMoveToVALUWorklist(FullDestReg, MRI, Worklist);
5483 }
5484 
splitScalar64BitXnor(SetVectorType & Worklist,MachineInstr & Inst,MachineDominatorTree * MDT) const5485 void SIInstrInfo::splitScalar64BitXnor(SetVectorType &Worklist,
5486                                        MachineInstr &Inst,
5487                                        MachineDominatorTree *MDT) const {
5488   MachineBasicBlock &MBB = *Inst.getParent();
5489   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
5490 
5491   MachineOperand &Dest = Inst.getOperand(0);
5492   MachineOperand &Src0 = Inst.getOperand(1);
5493   MachineOperand &Src1 = Inst.getOperand(2);
5494   const DebugLoc &DL = Inst.getDebugLoc();
5495 
5496   MachineBasicBlock::iterator MII = Inst;
5497 
5498   const TargetRegisterClass *DestRC = MRI.getRegClass(Dest.getReg());
5499 
5500   Register Interm = MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass);
5501 
5502   MachineOperand* Op0;
5503   MachineOperand* Op1;
5504 
5505   if (Src0.isReg() && RI.isSGPRReg(MRI, Src0.getReg())) {
5506     Op0 = &Src0;
5507     Op1 = &Src1;
5508   } else {
5509     Op0 = &Src1;
5510     Op1 = &Src0;
5511   }
5512 
5513   BuildMI(MBB, MII, DL, get(AMDGPU::S_NOT_B64), Interm)
5514     .add(*Op0);
5515 
5516   Register NewDest = MRI.createVirtualRegister(DestRC);
5517 
5518   MachineInstr &Xor = *BuildMI(MBB, MII, DL, get(AMDGPU::S_XOR_B64), NewDest)
5519     .addReg(Interm)
5520     .add(*Op1);
5521 
5522   MRI.replaceRegWith(Dest.getReg(), NewDest);
5523 
5524   Worklist.insert(&Xor);
5525 }
5526 
splitScalar64BitBCNT(SetVectorType & Worklist,MachineInstr & Inst) const5527 void SIInstrInfo::splitScalar64BitBCNT(
5528     SetVectorType &Worklist, MachineInstr &Inst) const {
5529   MachineBasicBlock &MBB = *Inst.getParent();
5530   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
5531 
5532   MachineBasicBlock::iterator MII = Inst;
5533   const DebugLoc &DL = Inst.getDebugLoc();
5534 
5535   MachineOperand &Dest = Inst.getOperand(0);
5536   MachineOperand &Src = Inst.getOperand(1);
5537 
5538   const MCInstrDesc &InstDesc = get(AMDGPU::V_BCNT_U32_B32_e64);
5539   const TargetRegisterClass *SrcRC = Src.isReg() ?
5540     MRI.getRegClass(Src.getReg()) :
5541     &AMDGPU::SGPR_32RegClass;
5542 
5543   Register MidReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5544   Register ResultReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5545 
5546   const TargetRegisterClass *SrcSubRC = RI.getSubRegClass(SrcRC, AMDGPU::sub0);
5547 
5548   MachineOperand SrcRegSub0 = buildExtractSubRegOrImm(MII, MRI, Src, SrcRC,
5549                                                       AMDGPU::sub0, SrcSubRC);
5550   MachineOperand SrcRegSub1 = buildExtractSubRegOrImm(MII, MRI, Src, SrcRC,
5551                                                       AMDGPU::sub1, SrcSubRC);
5552 
5553   BuildMI(MBB, MII, DL, InstDesc, MidReg).add(SrcRegSub0).addImm(0);
5554 
5555   BuildMI(MBB, MII, DL, InstDesc, ResultReg).add(SrcRegSub1).addReg(MidReg);
5556 
5557   MRI.replaceRegWith(Dest.getReg(), ResultReg);
5558 
5559   // We don't need to legalize operands here. src0 for etiher instruction can be
5560   // an SGPR, and the second input is unused or determined here.
5561   addUsersToMoveToVALUWorklist(ResultReg, MRI, Worklist);
5562 }
5563 
splitScalar64BitBFE(SetVectorType & Worklist,MachineInstr & Inst) const5564 void SIInstrInfo::splitScalar64BitBFE(SetVectorType &Worklist,
5565                                       MachineInstr &Inst) const {
5566   MachineBasicBlock &MBB = *Inst.getParent();
5567   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
5568   MachineBasicBlock::iterator MII = Inst;
5569   const DebugLoc &DL = Inst.getDebugLoc();
5570 
5571   MachineOperand &Dest = Inst.getOperand(0);
5572   uint32_t Imm = Inst.getOperand(2).getImm();
5573   uint32_t Offset = Imm & 0x3f; // Extract bits [5:0].
5574   uint32_t BitWidth = (Imm & 0x7f0000) >> 16; // Extract bits [22:16].
5575 
5576   (void) Offset;
5577 
5578   // Only sext_inreg cases handled.
5579   assert(Inst.getOpcode() == AMDGPU::S_BFE_I64 && BitWidth <= 32 &&
5580          Offset == 0 && "Not implemented");
5581 
5582   if (BitWidth < 32) {
5583     Register MidRegLo = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5584     Register MidRegHi = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5585     Register ResultReg = MRI.createVirtualRegister(&AMDGPU::VReg_64RegClass);
5586 
5587     BuildMI(MBB, MII, DL, get(AMDGPU::V_BFE_I32), MidRegLo)
5588         .addReg(Inst.getOperand(1).getReg(), 0, AMDGPU::sub0)
5589         .addImm(0)
5590         .addImm(BitWidth);
5591 
5592     BuildMI(MBB, MII, DL, get(AMDGPU::V_ASHRREV_I32_e32), MidRegHi)
5593       .addImm(31)
5594       .addReg(MidRegLo);
5595 
5596     BuildMI(MBB, MII, DL, get(TargetOpcode::REG_SEQUENCE), ResultReg)
5597       .addReg(MidRegLo)
5598       .addImm(AMDGPU::sub0)
5599       .addReg(MidRegHi)
5600       .addImm(AMDGPU::sub1);
5601 
5602     MRI.replaceRegWith(Dest.getReg(), ResultReg);
5603     addUsersToMoveToVALUWorklist(ResultReg, MRI, Worklist);
5604     return;
5605   }
5606 
5607   MachineOperand &Src = Inst.getOperand(1);
5608   Register TmpReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5609   Register ResultReg = MRI.createVirtualRegister(&AMDGPU::VReg_64RegClass);
5610 
5611   BuildMI(MBB, MII, DL, get(AMDGPU::V_ASHRREV_I32_e64), TmpReg)
5612     .addImm(31)
5613     .addReg(Src.getReg(), 0, AMDGPU::sub0);
5614 
5615   BuildMI(MBB, MII, DL, get(TargetOpcode::REG_SEQUENCE), ResultReg)
5616     .addReg(Src.getReg(), 0, AMDGPU::sub0)
5617     .addImm(AMDGPU::sub0)
5618     .addReg(TmpReg)
5619     .addImm(AMDGPU::sub1);
5620 
5621   MRI.replaceRegWith(Dest.getReg(), ResultReg);
5622   addUsersToMoveToVALUWorklist(ResultReg, MRI, Worklist);
5623 }
5624 
addUsersToMoveToVALUWorklist(unsigned DstReg,MachineRegisterInfo & MRI,SetVectorType & Worklist) const5625 void SIInstrInfo::addUsersToMoveToVALUWorklist(
5626   unsigned DstReg,
5627   MachineRegisterInfo &MRI,
5628   SetVectorType &Worklist) const {
5629   for (MachineRegisterInfo::use_iterator I = MRI.use_begin(DstReg),
5630          E = MRI.use_end(); I != E;) {
5631     MachineInstr &UseMI = *I->getParent();
5632 
5633     unsigned OpNo = 0;
5634 
5635     switch (UseMI.getOpcode()) {
5636     case AMDGPU::COPY:
5637     case AMDGPU::WQM:
5638     case AMDGPU::SOFT_WQM:
5639     case AMDGPU::WWM:
5640     case AMDGPU::REG_SEQUENCE:
5641     case AMDGPU::PHI:
5642     case AMDGPU::INSERT_SUBREG:
5643       break;
5644     default:
5645       OpNo = I.getOperandNo();
5646       break;
5647     }
5648 
5649     if (!RI.hasVectorRegisters(getOpRegClass(UseMI, OpNo))) {
5650       Worklist.insert(&UseMI);
5651 
5652       do {
5653         ++I;
5654       } while (I != E && I->getParent() == &UseMI);
5655     } else {
5656       ++I;
5657     }
5658   }
5659 }
5660 
movePackToVALU(SetVectorType & Worklist,MachineRegisterInfo & MRI,MachineInstr & Inst) const5661 void SIInstrInfo::movePackToVALU(SetVectorType &Worklist,
5662                                  MachineRegisterInfo &MRI,
5663                                  MachineInstr &Inst) const {
5664   Register ResultReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5665   MachineBasicBlock *MBB = Inst.getParent();
5666   MachineOperand &Src0 = Inst.getOperand(1);
5667   MachineOperand &Src1 = Inst.getOperand(2);
5668   const DebugLoc &DL = Inst.getDebugLoc();
5669 
5670   switch (Inst.getOpcode()) {
5671   case AMDGPU::S_PACK_LL_B32_B16: {
5672     Register ImmReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5673     Register TmpReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5674 
5675     // FIXME: Can do a lot better if we know the high bits of src0 or src1 are
5676     // 0.
5677     BuildMI(*MBB, Inst, DL, get(AMDGPU::V_MOV_B32_e32), ImmReg)
5678       .addImm(0xffff);
5679 
5680     BuildMI(*MBB, Inst, DL, get(AMDGPU::V_AND_B32_e64), TmpReg)
5681       .addReg(ImmReg, RegState::Kill)
5682       .add(Src0);
5683 
5684     BuildMI(*MBB, Inst, DL, get(AMDGPU::V_LSHL_OR_B32), ResultReg)
5685       .add(Src1)
5686       .addImm(16)
5687       .addReg(TmpReg, RegState::Kill);
5688     break;
5689   }
5690   case AMDGPU::S_PACK_LH_B32_B16: {
5691     Register ImmReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5692     BuildMI(*MBB, Inst, DL, get(AMDGPU::V_MOV_B32_e32), ImmReg)
5693       .addImm(0xffff);
5694     BuildMI(*MBB, Inst, DL, get(AMDGPU::V_BFI_B32), ResultReg)
5695       .addReg(ImmReg, RegState::Kill)
5696       .add(Src0)
5697       .add(Src1);
5698     break;
5699   }
5700   case AMDGPU::S_PACK_HH_B32_B16: {
5701     Register ImmReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5702     Register TmpReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
5703     BuildMI(*MBB, Inst, DL, get(AMDGPU::V_LSHRREV_B32_e64), TmpReg)
5704       .addImm(16)
5705       .add(Src0);
5706     BuildMI(*MBB, Inst, DL, get(AMDGPU::V_MOV_B32_e32), ImmReg)
5707       .addImm(0xffff0000);
5708     BuildMI(*MBB, Inst, DL, get(AMDGPU::V_AND_OR_B32), ResultReg)
5709       .add(Src1)
5710       .addReg(ImmReg, RegState::Kill)
5711       .addReg(TmpReg, RegState::Kill);
5712     break;
5713   }
5714   default:
5715     llvm_unreachable("unhandled s_pack_* instruction");
5716   }
5717 
5718   MachineOperand &Dest = Inst.getOperand(0);
5719   MRI.replaceRegWith(Dest.getReg(), ResultReg);
5720   addUsersToMoveToVALUWorklist(ResultReg, MRI, Worklist);
5721 }
5722 
addSCCDefUsersToVALUWorklist(MachineOperand & Op,MachineInstr & SCCDefInst,SetVectorType & Worklist) const5723 void SIInstrInfo::addSCCDefUsersToVALUWorklist(MachineOperand &Op,
5724                                                MachineInstr &SCCDefInst,
5725                                                SetVectorType &Worklist) const {
5726   // Ensure that def inst defines SCC, which is still live.
5727   assert(Op.isReg() && Op.getReg() == AMDGPU::SCC && Op.isDef() &&
5728          !Op.isDead() && Op.getParent() == &SCCDefInst);
5729   // This assumes that all the users of SCC are in the same block
5730   // as the SCC def.
5731   for (MachineInstr &MI : // Skip the def inst itself.
5732        make_range(std::next(MachineBasicBlock::iterator(SCCDefInst)),
5733                   SCCDefInst.getParent()->end())) {
5734     // Check if SCC is used first.
5735     if (MI.findRegisterUseOperandIdx(AMDGPU::SCC, false, &RI) != -1)
5736       Worklist.insert(&MI);
5737     // Exit if we find another SCC def.
5738     if (MI.findRegisterDefOperandIdx(AMDGPU::SCC, false, false, &RI) != -1)
5739       return;
5740   }
5741 }
5742 
getDestEquivalentVGPRClass(const MachineInstr & Inst) const5743 const TargetRegisterClass *SIInstrInfo::getDestEquivalentVGPRClass(
5744   const MachineInstr &Inst) const {
5745   const TargetRegisterClass *NewDstRC = getOpRegClass(Inst, 0);
5746 
5747   switch (Inst.getOpcode()) {
5748   // For target instructions, getOpRegClass just returns the virtual register
5749   // class associated with the operand, so we need to find an equivalent VGPR
5750   // register class in order to move the instruction to the VALU.
5751   case AMDGPU::COPY:
5752   case AMDGPU::PHI:
5753   case AMDGPU::REG_SEQUENCE:
5754   case AMDGPU::INSERT_SUBREG:
5755   case AMDGPU::WQM:
5756   case AMDGPU::SOFT_WQM:
5757   case AMDGPU::WWM: {
5758     const TargetRegisterClass *SrcRC = getOpRegClass(Inst, 1);
5759     if (RI.hasAGPRs(SrcRC)) {
5760       if (RI.hasAGPRs(NewDstRC))
5761         return nullptr;
5762 
5763       switch (Inst.getOpcode()) {
5764       case AMDGPU::PHI:
5765       case AMDGPU::REG_SEQUENCE:
5766       case AMDGPU::INSERT_SUBREG:
5767         NewDstRC = RI.getEquivalentAGPRClass(NewDstRC);
5768         break;
5769       default:
5770         NewDstRC = RI.getEquivalentVGPRClass(NewDstRC);
5771       }
5772 
5773       if (!NewDstRC)
5774         return nullptr;
5775     } else {
5776       if (RI.hasVGPRs(NewDstRC) || NewDstRC == &AMDGPU::VReg_1RegClass)
5777         return nullptr;
5778 
5779       NewDstRC = RI.getEquivalentVGPRClass(NewDstRC);
5780       if (!NewDstRC)
5781         return nullptr;
5782     }
5783 
5784     return NewDstRC;
5785   }
5786   default:
5787     return NewDstRC;
5788   }
5789 }
5790 
5791 // Find the one SGPR operand we are allowed to use.
findUsedSGPR(const MachineInstr & MI,int OpIndices[3]) const5792 unsigned SIInstrInfo::findUsedSGPR(const MachineInstr &MI,
5793                                    int OpIndices[3]) const {
5794   const MCInstrDesc &Desc = MI.getDesc();
5795 
5796   // Find the one SGPR operand we are allowed to use.
5797   //
5798   // First we need to consider the instruction's operand requirements before
5799   // legalizing. Some operands are required to be SGPRs, such as implicit uses
5800   // of VCC, but we are still bound by the constant bus requirement to only use
5801   // one.
5802   //
5803   // If the operand's class is an SGPR, we can never move it.
5804 
5805   unsigned SGPRReg = findImplicitSGPRRead(MI);
5806   if (SGPRReg != AMDGPU::NoRegister)
5807     return SGPRReg;
5808 
5809   unsigned UsedSGPRs[3] = { AMDGPU::NoRegister };
5810   const MachineRegisterInfo &MRI = MI.getParent()->getParent()->getRegInfo();
5811 
5812   for (unsigned i = 0; i < 3; ++i) {
5813     int Idx = OpIndices[i];
5814     if (Idx == -1)
5815       break;
5816 
5817     const MachineOperand &MO = MI.getOperand(Idx);
5818     if (!MO.isReg())
5819       continue;
5820 
5821     // Is this operand statically required to be an SGPR based on the operand
5822     // constraints?
5823     const TargetRegisterClass *OpRC = RI.getRegClass(Desc.OpInfo[Idx].RegClass);
5824     bool IsRequiredSGPR = RI.isSGPRClass(OpRC);
5825     if (IsRequiredSGPR)
5826       return MO.getReg();
5827 
5828     // If this could be a VGPR or an SGPR, Check the dynamic register class.
5829     Register Reg = MO.getReg();
5830     const TargetRegisterClass *RegRC = MRI.getRegClass(Reg);
5831     if (RI.isSGPRClass(RegRC))
5832       UsedSGPRs[i] = Reg;
5833   }
5834 
5835   // We don't have a required SGPR operand, so we have a bit more freedom in
5836   // selecting operands to move.
5837 
5838   // Try to select the most used SGPR. If an SGPR is equal to one of the
5839   // others, we choose that.
5840   //
5841   // e.g.
5842   // V_FMA_F32 v0, s0, s0, s0 -> No moves
5843   // V_FMA_F32 v0, s0, s1, s0 -> Move s1
5844 
5845   // TODO: If some of the operands are 64-bit SGPRs and some 32, we should
5846   // prefer those.
5847 
5848   if (UsedSGPRs[0] != AMDGPU::NoRegister) {
5849     if (UsedSGPRs[0] == UsedSGPRs[1] || UsedSGPRs[0] == UsedSGPRs[2])
5850       SGPRReg = UsedSGPRs[0];
5851   }
5852 
5853   if (SGPRReg == AMDGPU::NoRegister && UsedSGPRs[1] != AMDGPU::NoRegister) {
5854     if (UsedSGPRs[1] == UsedSGPRs[2])
5855       SGPRReg = UsedSGPRs[1];
5856   }
5857 
5858   return SGPRReg;
5859 }
5860 
getNamedOperand(MachineInstr & MI,unsigned OperandName) const5861 MachineOperand *SIInstrInfo::getNamedOperand(MachineInstr &MI,
5862                                              unsigned OperandName) const {
5863   int Idx = AMDGPU::getNamedOperandIdx(MI.getOpcode(), OperandName);
5864   if (Idx == -1)
5865     return nullptr;
5866 
5867   return &MI.getOperand(Idx);
5868 }
5869 
getDefaultRsrcDataFormat() const5870 uint64_t SIInstrInfo::getDefaultRsrcDataFormat() const {
5871   if (ST.getGeneration() >= AMDGPUSubtarget::GFX10) {
5872     return (22ULL << 44) | // IMG_FORMAT_32_FLOAT
5873            (1ULL << 56) | // RESOURCE_LEVEL = 1
5874            (3ULL << 60); // OOB_SELECT = 3
5875   }
5876 
5877   uint64_t RsrcDataFormat = AMDGPU::RSRC_DATA_FORMAT;
5878   if (ST.isAmdHsaOS()) {
5879     // Set ATC = 1. GFX9 doesn't have this bit.
5880     if (ST.getGeneration() <= AMDGPUSubtarget::VOLCANIC_ISLANDS)
5881       RsrcDataFormat |= (1ULL << 56);
5882 
5883     // Set MTYPE = 2 (MTYPE_UC = uncached). GFX9 doesn't have this.
5884     // BTW, it disables TC L2 and therefore decreases performance.
5885     if (ST.getGeneration() == AMDGPUSubtarget::VOLCANIC_ISLANDS)
5886       RsrcDataFormat |= (2ULL << 59);
5887   }
5888 
5889   return RsrcDataFormat;
5890 }
5891 
getScratchRsrcWords23() const5892 uint64_t SIInstrInfo::getScratchRsrcWords23() const {
5893   uint64_t Rsrc23 = getDefaultRsrcDataFormat() |
5894                     AMDGPU::RSRC_TID_ENABLE |
5895                     0xffffffff; // Size;
5896 
5897   // GFX9 doesn't have ELEMENT_SIZE.
5898   if (ST.getGeneration() <= AMDGPUSubtarget::VOLCANIC_ISLANDS) {
5899     uint64_t EltSizeValue = Log2_32(ST.getMaxPrivateElementSize()) - 1;
5900     Rsrc23 |= EltSizeValue << AMDGPU::RSRC_ELEMENT_SIZE_SHIFT;
5901   }
5902 
5903   // IndexStride = 64 / 32.
5904   uint64_t IndexStride = ST.getWavefrontSize() == 64 ? 3 : 2;
5905   Rsrc23 |= IndexStride << AMDGPU::RSRC_INDEX_STRIDE_SHIFT;
5906 
5907   // If TID_ENABLE is set, DATA_FORMAT specifies stride bits [14:17].
5908   // Clear them unless we want a huge stride.
5909   if (ST.getGeneration() >= AMDGPUSubtarget::VOLCANIC_ISLANDS &&
5910       ST.getGeneration() <= AMDGPUSubtarget::GFX9)
5911     Rsrc23 &= ~AMDGPU::RSRC_DATA_FORMAT;
5912 
5913   return Rsrc23;
5914 }
5915 
isLowLatencyInstruction(const MachineInstr & MI) const5916 bool SIInstrInfo::isLowLatencyInstruction(const MachineInstr &MI) const {
5917   unsigned Opc = MI.getOpcode();
5918 
5919   return isSMRD(Opc);
5920 }
5921 
isHighLatencyInstruction(const MachineInstr & MI) const5922 bool SIInstrInfo::isHighLatencyInstruction(const MachineInstr &MI) const {
5923   unsigned Opc = MI.getOpcode();
5924 
5925   return isMUBUF(Opc) || isMTBUF(Opc) || isMIMG(Opc);
5926 }
5927 
isStackAccess(const MachineInstr & MI,int & FrameIndex) const5928 unsigned SIInstrInfo::isStackAccess(const MachineInstr &MI,
5929                                     int &FrameIndex) const {
5930   const MachineOperand *Addr = getNamedOperand(MI, AMDGPU::OpName::vaddr);
5931   if (!Addr || !Addr->isFI())
5932     return AMDGPU::NoRegister;
5933 
5934   assert(!MI.memoperands_empty() &&
5935          (*MI.memoperands_begin())->getAddrSpace() == AMDGPUAS::PRIVATE_ADDRESS);
5936 
5937   FrameIndex = Addr->getIndex();
5938   return getNamedOperand(MI, AMDGPU::OpName::vdata)->getReg();
5939 }
5940 
isSGPRStackAccess(const MachineInstr & MI,int & FrameIndex) const5941 unsigned SIInstrInfo::isSGPRStackAccess(const MachineInstr &MI,
5942                                         int &FrameIndex) const {
5943   const MachineOperand *Addr = getNamedOperand(MI, AMDGPU::OpName::addr);
5944   assert(Addr && Addr->isFI());
5945   FrameIndex = Addr->getIndex();
5946   return getNamedOperand(MI, AMDGPU::OpName::data)->getReg();
5947 }
5948 
isLoadFromStackSlot(const MachineInstr & MI,int & FrameIndex) const5949 unsigned SIInstrInfo::isLoadFromStackSlot(const MachineInstr &MI,
5950                                           int &FrameIndex) const {
5951   if (!MI.mayLoad())
5952     return AMDGPU::NoRegister;
5953 
5954   if (isMUBUF(MI) || isVGPRSpill(MI))
5955     return isStackAccess(MI, FrameIndex);
5956 
5957   if (isSGPRSpill(MI))
5958     return isSGPRStackAccess(MI, FrameIndex);
5959 
5960   return AMDGPU::NoRegister;
5961 }
5962 
isStoreToStackSlot(const MachineInstr & MI,int & FrameIndex) const5963 unsigned SIInstrInfo::isStoreToStackSlot(const MachineInstr &MI,
5964                                          int &FrameIndex) const {
5965   if (!MI.mayStore())
5966     return AMDGPU::NoRegister;
5967 
5968   if (isMUBUF(MI) || isVGPRSpill(MI))
5969     return isStackAccess(MI, FrameIndex);
5970 
5971   if (isSGPRSpill(MI))
5972     return isSGPRStackAccess(MI, FrameIndex);
5973 
5974   return AMDGPU::NoRegister;
5975 }
5976 
getInstBundleSize(const MachineInstr & MI) const5977 unsigned SIInstrInfo::getInstBundleSize(const MachineInstr &MI) const {
5978   unsigned Size = 0;
5979   MachineBasicBlock::const_instr_iterator I = MI.getIterator();
5980   MachineBasicBlock::const_instr_iterator E = MI.getParent()->instr_end();
5981   while (++I != E && I->isInsideBundle()) {
5982     assert(!I->isBundle() && "No nested bundle!");
5983     Size += getInstSizeInBytes(*I);
5984   }
5985 
5986   return Size;
5987 }
5988 
getInstSizeInBytes(const MachineInstr & MI) const5989 unsigned SIInstrInfo::getInstSizeInBytes(const MachineInstr &MI) const {
5990   unsigned Opc = MI.getOpcode();
5991   const MCInstrDesc &Desc = getMCOpcodeFromPseudo(Opc);
5992   unsigned DescSize = Desc.getSize();
5993 
5994   // If we have a definitive size, we can use it. Otherwise we need to inspect
5995   // the operands to know the size.
5996   if (isFixedSize(MI))
5997     return DescSize;
5998 
5999   // 4-byte instructions may have a 32-bit literal encoded after them. Check
6000   // operands that coud ever be literals.
6001   if (isVALU(MI) || isSALU(MI)) {
6002     int Src0Idx = AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src0);
6003     if (Src0Idx == -1)
6004       return DescSize; // No operands.
6005 
6006     if (isLiteralConstantLike(MI.getOperand(Src0Idx), Desc.OpInfo[Src0Idx]))
6007       return isVOP3(MI) ? 12 : (DescSize + 4);
6008 
6009     int Src1Idx = AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src1);
6010     if (Src1Idx == -1)
6011       return DescSize;
6012 
6013     if (isLiteralConstantLike(MI.getOperand(Src1Idx), Desc.OpInfo[Src1Idx]))
6014       return isVOP3(MI) ? 12 : (DescSize + 4);
6015 
6016     int Src2Idx = AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::src2);
6017     if (Src2Idx == -1)
6018       return DescSize;
6019 
6020     if (isLiteralConstantLike(MI.getOperand(Src2Idx), Desc.OpInfo[Src2Idx]))
6021       return isVOP3(MI) ? 12 : (DescSize + 4);
6022 
6023     return DescSize;
6024   }
6025 
6026   // Check whether we have extra NSA words.
6027   if (isMIMG(MI)) {
6028     int VAddr0Idx = AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::vaddr0);
6029     if (VAddr0Idx < 0)
6030       return 8;
6031 
6032     int RSrcIdx = AMDGPU::getNamedOperandIdx(Opc, AMDGPU::OpName::srsrc);
6033     return 8 + 4 * ((RSrcIdx - VAddr0Idx + 2) / 4);
6034   }
6035 
6036   switch (Opc) {
6037   case TargetOpcode::IMPLICIT_DEF:
6038   case TargetOpcode::KILL:
6039   case TargetOpcode::DBG_VALUE:
6040   case TargetOpcode::EH_LABEL:
6041     return 0;
6042   case TargetOpcode::BUNDLE:
6043     return getInstBundleSize(MI);
6044   case TargetOpcode::INLINEASM:
6045   case TargetOpcode::INLINEASM_BR: {
6046     const MachineFunction *MF = MI.getParent()->getParent();
6047     const char *AsmStr = MI.getOperand(0).getSymbolName();
6048     return getInlineAsmLength(AsmStr, *MF->getTarget().getMCAsmInfo(),
6049                               &MF->getSubtarget());
6050   }
6051   default:
6052     return DescSize;
6053   }
6054 }
6055 
mayAccessFlatAddressSpace(const MachineInstr & MI) const6056 bool SIInstrInfo::mayAccessFlatAddressSpace(const MachineInstr &MI) const {
6057   if (!isFLAT(MI))
6058     return false;
6059 
6060   if (MI.memoperands_empty())
6061     return true;
6062 
6063   for (const MachineMemOperand *MMO : MI.memoperands()) {
6064     if (MMO->getAddrSpace() == AMDGPUAS::FLAT_ADDRESS)
6065       return true;
6066   }
6067   return false;
6068 }
6069 
isNonUniformBranchInstr(MachineInstr & Branch) const6070 bool SIInstrInfo::isNonUniformBranchInstr(MachineInstr &Branch) const {
6071   return Branch.getOpcode() == AMDGPU::SI_NON_UNIFORM_BRCOND_PSEUDO;
6072 }
6073 
convertNonUniformIfRegion(MachineBasicBlock * IfEntry,MachineBasicBlock * IfEnd) const6074 void SIInstrInfo::convertNonUniformIfRegion(MachineBasicBlock *IfEntry,
6075                                             MachineBasicBlock *IfEnd) const {
6076   MachineBasicBlock::iterator TI = IfEntry->getFirstTerminator();
6077   assert(TI != IfEntry->end());
6078 
6079   MachineInstr *Branch = &(*TI);
6080   MachineFunction *MF = IfEntry->getParent();
6081   MachineRegisterInfo &MRI = IfEntry->getParent()->getRegInfo();
6082 
6083   if (Branch->getOpcode() == AMDGPU::SI_NON_UNIFORM_BRCOND_PSEUDO) {
6084     Register DstReg = MRI.createVirtualRegister(RI.getBoolRC());
6085     MachineInstr *SIIF =
6086         BuildMI(*MF, Branch->getDebugLoc(), get(AMDGPU::SI_IF), DstReg)
6087             .add(Branch->getOperand(0))
6088             .add(Branch->getOperand(1));
6089     MachineInstr *SIEND =
6090         BuildMI(*MF, Branch->getDebugLoc(), get(AMDGPU::SI_END_CF))
6091             .addReg(DstReg);
6092 
6093     IfEntry->erase(TI);
6094     IfEntry->insert(IfEntry->end(), SIIF);
6095     IfEnd->insert(IfEnd->getFirstNonPHI(), SIEND);
6096   }
6097 }
6098 
convertNonUniformLoopRegion(MachineBasicBlock * LoopEntry,MachineBasicBlock * LoopEnd) const6099 void SIInstrInfo::convertNonUniformLoopRegion(
6100     MachineBasicBlock *LoopEntry, MachineBasicBlock *LoopEnd) const {
6101   MachineBasicBlock::iterator TI = LoopEnd->getFirstTerminator();
6102   // We expect 2 terminators, one conditional and one unconditional.
6103   assert(TI != LoopEnd->end());
6104 
6105   MachineInstr *Branch = &(*TI);
6106   MachineFunction *MF = LoopEnd->getParent();
6107   MachineRegisterInfo &MRI = LoopEnd->getParent()->getRegInfo();
6108 
6109   if (Branch->getOpcode() == AMDGPU::SI_NON_UNIFORM_BRCOND_PSEUDO) {
6110 
6111     Register DstReg = MRI.createVirtualRegister(RI.getBoolRC());
6112     Register BackEdgeReg = MRI.createVirtualRegister(RI.getBoolRC());
6113     MachineInstrBuilder HeaderPHIBuilder =
6114         BuildMI(*(MF), Branch->getDebugLoc(), get(TargetOpcode::PHI), DstReg);
6115     for (MachineBasicBlock::pred_iterator PI = LoopEntry->pred_begin(),
6116                                           E = LoopEntry->pred_end();
6117          PI != E; ++PI) {
6118       if (*PI == LoopEnd) {
6119         HeaderPHIBuilder.addReg(BackEdgeReg);
6120       } else {
6121         MachineBasicBlock *PMBB = *PI;
6122         Register ZeroReg = MRI.createVirtualRegister(RI.getBoolRC());
6123         materializeImmediate(*PMBB, PMBB->getFirstTerminator(), DebugLoc(),
6124                              ZeroReg, 0);
6125         HeaderPHIBuilder.addReg(ZeroReg);
6126       }
6127       HeaderPHIBuilder.addMBB(*PI);
6128     }
6129     MachineInstr *HeaderPhi = HeaderPHIBuilder;
6130     MachineInstr *SIIFBREAK = BuildMI(*(MF), Branch->getDebugLoc(),
6131                                       get(AMDGPU::SI_IF_BREAK), BackEdgeReg)
6132                                   .addReg(DstReg)
6133                                   .add(Branch->getOperand(0));
6134     MachineInstr *SILOOP =
6135         BuildMI(*(MF), Branch->getDebugLoc(), get(AMDGPU::SI_LOOP))
6136             .addReg(BackEdgeReg)
6137             .addMBB(LoopEntry);
6138 
6139     LoopEntry->insert(LoopEntry->begin(), HeaderPhi);
6140     LoopEnd->erase(TI);
6141     LoopEnd->insert(LoopEnd->end(), SIIFBREAK);
6142     LoopEnd->insert(LoopEnd->end(), SILOOP);
6143   }
6144 }
6145 
6146 ArrayRef<std::pair<int, const char *>>
getSerializableTargetIndices() const6147 SIInstrInfo::getSerializableTargetIndices() const {
6148   static const std::pair<int, const char *> TargetIndices[] = {
6149       {AMDGPU::TI_CONSTDATA_START, "amdgpu-constdata-start"},
6150       {AMDGPU::TI_SCRATCH_RSRC_DWORD0, "amdgpu-scratch-rsrc-dword0"},
6151       {AMDGPU::TI_SCRATCH_RSRC_DWORD1, "amdgpu-scratch-rsrc-dword1"},
6152       {AMDGPU::TI_SCRATCH_RSRC_DWORD2, "amdgpu-scratch-rsrc-dword2"},
6153       {AMDGPU::TI_SCRATCH_RSRC_DWORD3, "amdgpu-scratch-rsrc-dword3"}};
6154   return makeArrayRef(TargetIndices);
6155 }
6156 
6157 /// This is used by the post-RA scheduler (SchedulePostRAList.cpp).  The
6158 /// post-RA version of misched uses CreateTargetMIHazardRecognizer.
6159 ScheduleHazardRecognizer *
CreateTargetPostRAHazardRecognizer(const InstrItineraryData * II,const ScheduleDAG * DAG) const6160 SIInstrInfo::CreateTargetPostRAHazardRecognizer(const InstrItineraryData *II,
6161                                             const ScheduleDAG *DAG) const {
6162   return new GCNHazardRecognizer(DAG->MF);
6163 }
6164 
6165 /// This is the hazard recognizer used at -O0 by the PostRAHazardRecognizer
6166 /// pass.
6167 ScheduleHazardRecognizer *
CreateTargetPostRAHazardRecognizer(const MachineFunction & MF) const6168 SIInstrInfo::CreateTargetPostRAHazardRecognizer(const MachineFunction &MF) const {
6169   return new GCNHazardRecognizer(MF);
6170 }
6171 
6172 std::pair<unsigned, unsigned>
decomposeMachineOperandsTargetFlags(unsigned TF) const6173 SIInstrInfo::decomposeMachineOperandsTargetFlags(unsigned TF) const {
6174   return std::make_pair(TF & MO_MASK, TF & ~MO_MASK);
6175 }
6176 
6177 ArrayRef<std::pair<unsigned, const char *>>
getSerializableDirectMachineOperandTargetFlags() const6178 SIInstrInfo::getSerializableDirectMachineOperandTargetFlags() const {
6179   static const std::pair<unsigned, const char *> TargetFlags[] = {
6180     { MO_GOTPCREL, "amdgpu-gotprel" },
6181     { MO_GOTPCREL32_LO, "amdgpu-gotprel32-lo" },
6182     { MO_GOTPCREL32_HI, "amdgpu-gotprel32-hi" },
6183     { MO_REL32_LO, "amdgpu-rel32-lo" },
6184     { MO_REL32_HI, "amdgpu-rel32-hi" },
6185     { MO_ABS32_LO, "amdgpu-abs32-lo" },
6186     { MO_ABS32_HI, "amdgpu-abs32-hi" },
6187   };
6188 
6189   return makeArrayRef(TargetFlags);
6190 }
6191 
isBasicBlockPrologue(const MachineInstr & MI) const6192 bool SIInstrInfo::isBasicBlockPrologue(const MachineInstr &MI) const {
6193   return !MI.isTerminator() && MI.getOpcode() != AMDGPU::COPY &&
6194          MI.modifiesRegister(AMDGPU::EXEC, &RI);
6195 }
6196 
6197 MachineInstrBuilder
getAddNoCarry(MachineBasicBlock & MBB,MachineBasicBlock::iterator I,const DebugLoc & DL,unsigned DestReg) const6198 SIInstrInfo::getAddNoCarry(MachineBasicBlock &MBB,
6199                            MachineBasicBlock::iterator I,
6200                            const DebugLoc &DL,
6201                            unsigned DestReg) const {
6202   if (ST.hasAddNoCarry())
6203     return BuildMI(MBB, I, DL, get(AMDGPU::V_ADD_U32_e64), DestReg);
6204 
6205   MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
6206   Register UnusedCarry = MRI.createVirtualRegister(RI.getBoolRC());
6207   MRI.setRegAllocationHint(UnusedCarry, 0, RI.getVCC());
6208 
6209   return BuildMI(MBB, I, DL, get(AMDGPU::V_ADD_I32_e64), DestReg)
6210            .addReg(UnusedCarry, RegState::Define | RegState::Dead);
6211 }
6212 
getAddNoCarry(MachineBasicBlock & MBB,MachineBasicBlock::iterator I,const DebugLoc & DL,Register DestReg,RegScavenger & RS) const6213 MachineInstrBuilder SIInstrInfo::getAddNoCarry(MachineBasicBlock &MBB,
6214                                                MachineBasicBlock::iterator I,
6215                                                const DebugLoc &DL,
6216                                                Register DestReg,
6217                                                RegScavenger &RS) const {
6218   if (ST.hasAddNoCarry())
6219     return BuildMI(MBB, I, DL, get(AMDGPU::V_ADD_U32_e32), DestReg);
6220 
6221   // If available, prefer to use vcc.
6222   Register UnusedCarry = !RS.isRegUsed(AMDGPU::VCC)
6223                              ? Register(RI.getVCC())
6224                              : RS.scavengeRegister(RI.getBoolRC(), I, 0, false);
6225 
6226   // TODO: Users need to deal with this.
6227   if (!UnusedCarry.isValid())
6228     return MachineInstrBuilder();
6229 
6230   return BuildMI(MBB, I, DL, get(AMDGPU::V_ADD_I32_e64), DestReg)
6231            .addReg(UnusedCarry, RegState::Define | RegState::Dead);
6232 }
6233 
isKillTerminator(unsigned Opcode)6234 bool SIInstrInfo::isKillTerminator(unsigned Opcode) {
6235   switch (Opcode) {
6236   case AMDGPU::SI_KILL_F32_COND_IMM_TERMINATOR:
6237   case AMDGPU::SI_KILL_I1_TERMINATOR:
6238     return true;
6239   default:
6240     return false;
6241   }
6242 }
6243 
getKillTerminatorFromPseudo(unsigned Opcode) const6244 const MCInstrDesc &SIInstrInfo::getKillTerminatorFromPseudo(unsigned Opcode) const {
6245   switch (Opcode) {
6246   case AMDGPU::SI_KILL_F32_COND_IMM_PSEUDO:
6247     return get(AMDGPU::SI_KILL_F32_COND_IMM_TERMINATOR);
6248   case AMDGPU::SI_KILL_I1_PSEUDO:
6249     return get(AMDGPU::SI_KILL_I1_TERMINATOR);
6250   default:
6251     llvm_unreachable("invalid opcode, expected SI_KILL_*_PSEUDO");
6252   }
6253 }
6254 
fixImplicitOperands(MachineInstr & MI) const6255 void SIInstrInfo::fixImplicitOperands(MachineInstr &MI) const {
6256   MachineBasicBlock *MBB = MI.getParent();
6257   MachineFunction *MF = MBB->getParent();
6258   const GCNSubtarget &ST = MF->getSubtarget<GCNSubtarget>();
6259 
6260   if (!ST.isWave32())
6261     return;
6262 
6263   for (auto &Op : MI.implicit_operands()) {
6264     if (Op.isReg() && Op.getReg() == AMDGPU::VCC)
6265       Op.setReg(AMDGPU::VCC_LO);
6266   }
6267 }
6268 
isBufferSMRD(const MachineInstr & MI) const6269 bool SIInstrInfo::isBufferSMRD(const MachineInstr &MI) const {
6270   if (!isSMRD(MI))
6271     return false;
6272 
6273   // Check that it is using a buffer resource.
6274   int Idx = AMDGPU::getNamedOperandIdx(MI.getOpcode(), AMDGPU::OpName::sbase);
6275   if (Idx == -1) // e.g. s_memtime
6276     return false;
6277 
6278   const auto RCID = MI.getDesc().OpInfo[Idx].RegClass;
6279   return RI.getRegClass(RCID)->hasSubClassEq(&AMDGPU::SGPR_128RegClass);
6280 }
6281 
getNumFlatOffsetBits(unsigned AddrSpace,bool Signed) const6282 unsigned SIInstrInfo::getNumFlatOffsetBits(unsigned AddrSpace,
6283                                            bool Signed) const {
6284   if (!ST.hasFlatInstOffsets())
6285     return 0;
6286 
6287   if (ST.hasFlatSegmentOffsetBug() && AddrSpace == AMDGPUAS::FLAT_ADDRESS)
6288     return 0;
6289 
6290   if (ST.getGeneration() >= AMDGPUSubtarget::GFX10)
6291     return Signed ? 12 : 11;
6292 
6293   return Signed ? 13 : 12;
6294 }
6295 
isLegalFLATOffset(int64_t Offset,unsigned AddrSpace,bool Signed) const6296 bool SIInstrInfo::isLegalFLATOffset(int64_t Offset, unsigned AddrSpace,
6297                                     bool Signed) const {
6298   // TODO: Should 0 be special cased?
6299   if (!ST.hasFlatInstOffsets())
6300     return false;
6301 
6302   if (ST.hasFlatSegmentOffsetBug() && AddrSpace == AMDGPUAS::FLAT_ADDRESS)
6303     return false;
6304 
6305   if (ST.getGeneration() >= AMDGPUSubtarget::GFX10) {
6306     return (Signed && isInt<12>(Offset)) ||
6307            (!Signed && isUInt<11>(Offset));
6308   }
6309 
6310   return (Signed && isInt<13>(Offset)) ||
6311          (!Signed && isUInt<12>(Offset));
6312 }
6313 
6314 
6315 // This must be kept in sync with the SIEncodingFamily class in SIInstrInfo.td
6316 enum SIEncodingFamily {
6317   SI = 0,
6318   VI = 1,
6319   SDWA = 2,
6320   SDWA9 = 3,
6321   GFX80 = 4,
6322   GFX9 = 5,
6323   GFX10 = 6,
6324   SDWA10 = 7
6325 };
6326 
subtargetEncodingFamily(const GCNSubtarget & ST)6327 static SIEncodingFamily subtargetEncodingFamily(const GCNSubtarget &ST) {
6328   switch (ST.getGeneration()) {
6329   default:
6330     break;
6331   case AMDGPUSubtarget::SOUTHERN_ISLANDS:
6332   case AMDGPUSubtarget::SEA_ISLANDS:
6333     return SIEncodingFamily::SI;
6334   case AMDGPUSubtarget::VOLCANIC_ISLANDS:
6335   case AMDGPUSubtarget::GFX9:
6336     return SIEncodingFamily::VI;
6337   case AMDGPUSubtarget::GFX10:
6338     return SIEncodingFamily::GFX10;
6339   }
6340   llvm_unreachable("Unknown subtarget generation!");
6341 }
6342 
isAsmOnlyOpcode(int MCOp) const6343 bool SIInstrInfo::isAsmOnlyOpcode(int MCOp) const {
6344   switch(MCOp) {
6345   // These opcodes use indirect register addressing so
6346   // they need special handling by codegen (currently missing).
6347   // Therefore it is too risky to allow these opcodes
6348   // to be selected by dpp combiner or sdwa peepholer.
6349   case AMDGPU::V_MOVRELS_B32_dpp_gfx10:
6350   case AMDGPU::V_MOVRELS_B32_sdwa_gfx10:
6351   case AMDGPU::V_MOVRELD_B32_dpp_gfx10:
6352   case AMDGPU::V_MOVRELD_B32_sdwa_gfx10:
6353   case AMDGPU::V_MOVRELSD_B32_dpp_gfx10:
6354   case AMDGPU::V_MOVRELSD_B32_sdwa_gfx10:
6355   case AMDGPU::V_MOVRELSD_2_B32_dpp_gfx10:
6356   case AMDGPU::V_MOVRELSD_2_B32_sdwa_gfx10:
6357     return true;
6358   default:
6359     return false;
6360   }
6361 }
6362 
pseudoToMCOpcode(int Opcode) const6363 int SIInstrInfo::pseudoToMCOpcode(int Opcode) const {
6364   SIEncodingFamily Gen = subtargetEncodingFamily(ST);
6365 
6366   if ((get(Opcode).TSFlags & SIInstrFlags::renamedInGFX9) != 0 &&
6367     ST.getGeneration() == AMDGPUSubtarget::GFX9)
6368     Gen = SIEncodingFamily::GFX9;
6369 
6370   // Adjust the encoding family to GFX80 for D16 buffer instructions when the
6371   // subtarget has UnpackedD16VMem feature.
6372   // TODO: remove this when we discard GFX80 encoding.
6373   if (ST.hasUnpackedD16VMem() && (get(Opcode).TSFlags & SIInstrFlags::D16Buf))
6374     Gen = SIEncodingFamily::GFX80;
6375 
6376   if (get(Opcode).TSFlags & SIInstrFlags::SDWA) {
6377     switch (ST.getGeneration()) {
6378     default:
6379       Gen = SIEncodingFamily::SDWA;
6380       break;
6381     case AMDGPUSubtarget::GFX9:
6382       Gen = SIEncodingFamily::SDWA9;
6383       break;
6384     case AMDGPUSubtarget::GFX10:
6385       Gen = SIEncodingFamily::SDWA10;
6386       break;
6387     }
6388   }
6389 
6390   int MCOp = AMDGPU::getMCOpcode(Opcode, Gen);
6391 
6392   // -1 means that Opcode is already a native instruction.
6393   if (MCOp == -1)
6394     return Opcode;
6395 
6396   // (uint16_t)-1 means that Opcode is a pseudo instruction that has
6397   // no encoding in the given subtarget generation.
6398   if (MCOp == (uint16_t)-1)
6399     return -1;
6400 
6401   if (isAsmOnlyOpcode(MCOp))
6402     return -1;
6403 
6404   return MCOp;
6405 }
6406 
6407 static
getRegOrUndef(const MachineOperand & RegOpnd)6408 TargetInstrInfo::RegSubRegPair getRegOrUndef(const MachineOperand &RegOpnd) {
6409   assert(RegOpnd.isReg());
6410   return RegOpnd.isUndef() ? TargetInstrInfo::RegSubRegPair() :
6411                              getRegSubRegPair(RegOpnd);
6412 }
6413 
6414 TargetInstrInfo::RegSubRegPair
getRegSequenceSubReg(MachineInstr & MI,unsigned SubReg)6415 llvm::getRegSequenceSubReg(MachineInstr &MI, unsigned SubReg) {
6416   assert(MI.isRegSequence());
6417   for (unsigned I = 0, E = (MI.getNumOperands() - 1)/ 2; I < E; ++I)
6418     if (MI.getOperand(1 + 2 * I + 1).getImm() == SubReg) {
6419       auto &RegOp = MI.getOperand(1 + 2 * I);
6420       return getRegOrUndef(RegOp);
6421     }
6422   return TargetInstrInfo::RegSubRegPair();
6423 }
6424 
6425 // Try to find the definition of reg:subreg in subreg-manipulation pseudos
6426 // Following a subreg of reg:subreg isn't supported
followSubRegDef(MachineInstr & MI,TargetInstrInfo::RegSubRegPair & RSR)6427 static bool followSubRegDef(MachineInstr &MI,
6428                             TargetInstrInfo::RegSubRegPair &RSR) {
6429   if (!RSR.SubReg)
6430     return false;
6431   switch (MI.getOpcode()) {
6432   default: break;
6433   case AMDGPU::REG_SEQUENCE:
6434     RSR = getRegSequenceSubReg(MI, RSR.SubReg);
6435     return true;
6436   // EXTRACT_SUBREG ins't supported as this would follow a subreg of subreg
6437   case AMDGPU::INSERT_SUBREG:
6438     if (RSR.SubReg == (unsigned)MI.getOperand(3).getImm())
6439       // inserted the subreg we're looking for
6440       RSR = getRegOrUndef(MI.getOperand(2));
6441     else { // the subreg in the rest of the reg
6442       auto R1 = getRegOrUndef(MI.getOperand(1));
6443       if (R1.SubReg) // subreg of subreg isn't supported
6444         return false;
6445       RSR.Reg = R1.Reg;
6446     }
6447     return true;
6448   }
6449   return false;
6450 }
6451 
getVRegSubRegDef(const TargetInstrInfo::RegSubRegPair & P,MachineRegisterInfo & MRI)6452 MachineInstr *llvm::getVRegSubRegDef(const TargetInstrInfo::RegSubRegPair &P,
6453                                      MachineRegisterInfo &MRI) {
6454   assert(MRI.isSSA());
6455   if (!Register::isVirtualRegister(P.Reg))
6456     return nullptr;
6457 
6458   auto RSR = P;
6459   auto *DefInst = MRI.getVRegDef(RSR.Reg);
6460   while (auto *MI = DefInst) {
6461     DefInst = nullptr;
6462     switch (MI->getOpcode()) {
6463     case AMDGPU::COPY:
6464     case AMDGPU::V_MOV_B32_e32: {
6465       auto &Op1 = MI->getOperand(1);
6466       if (Op1.isReg() && Register::isVirtualRegister(Op1.getReg())) {
6467         if (Op1.isUndef())
6468           return nullptr;
6469         RSR = getRegSubRegPair(Op1);
6470         DefInst = MRI.getVRegDef(RSR.Reg);
6471       }
6472       break;
6473     }
6474     default:
6475       if (followSubRegDef(*MI, RSR)) {
6476         if (!RSR.Reg)
6477           return nullptr;
6478         DefInst = MRI.getVRegDef(RSR.Reg);
6479       }
6480     }
6481     if (!DefInst)
6482       return MI;
6483   }
6484   return nullptr;
6485 }
6486 
execMayBeModifiedBeforeUse(const MachineRegisterInfo & MRI,Register VReg,const MachineInstr & DefMI,const MachineInstr & UseMI)6487 bool llvm::execMayBeModifiedBeforeUse(const MachineRegisterInfo &MRI,
6488                                       Register VReg,
6489                                       const MachineInstr &DefMI,
6490                                       const MachineInstr &UseMI) {
6491   assert(MRI.isSSA() && "Must be run on SSA");
6492 
6493   auto *TRI = MRI.getTargetRegisterInfo();
6494   auto *DefBB = DefMI.getParent();
6495 
6496   // Don't bother searching between blocks, although it is possible this block
6497   // doesn't modify exec.
6498   if (UseMI.getParent() != DefBB)
6499     return true;
6500 
6501   const int MaxInstScan = 20;
6502   int NumInst = 0;
6503 
6504   // Stop scan at the use.
6505   auto E = UseMI.getIterator();
6506   for (auto I = std::next(DefMI.getIterator()); I != E; ++I) {
6507     if (I->isDebugInstr())
6508       continue;
6509 
6510     if (++NumInst > MaxInstScan)
6511       return true;
6512 
6513     if (I->modifiesRegister(AMDGPU::EXEC, TRI))
6514       return true;
6515   }
6516 
6517   return false;
6518 }
6519 
execMayBeModifiedBeforeAnyUse(const MachineRegisterInfo & MRI,Register VReg,const MachineInstr & DefMI)6520 bool llvm::execMayBeModifiedBeforeAnyUse(const MachineRegisterInfo &MRI,
6521                                          Register VReg,
6522                                          const MachineInstr &DefMI) {
6523   assert(MRI.isSSA() && "Must be run on SSA");
6524 
6525   auto *TRI = MRI.getTargetRegisterInfo();
6526   auto *DefBB = DefMI.getParent();
6527 
6528   const int MaxUseInstScan = 10;
6529   int NumUseInst = 0;
6530 
6531   for (auto &UseInst : MRI.use_nodbg_instructions(VReg)) {
6532     // Don't bother searching between blocks, although it is possible this block
6533     // doesn't modify exec.
6534     if (UseInst.getParent() != DefBB)
6535       return true;
6536 
6537     if (++NumUseInst > MaxUseInstScan)
6538       return true;
6539   }
6540 
6541   const int MaxInstScan = 20;
6542   int NumInst = 0;
6543 
6544   // Stop scan when we have seen all the uses.
6545   for (auto I = std::next(DefMI.getIterator()); ; ++I) {
6546     if (I->isDebugInstr())
6547       continue;
6548 
6549     if (++NumInst > MaxInstScan)
6550       return true;
6551 
6552     if (I->readsRegister(VReg))
6553       if (--NumUseInst == 0)
6554         return false;
6555 
6556     if (I->modifiesRegister(AMDGPU::EXEC, TRI))
6557       return true;
6558   }
6559 }
6560 
createPHIDestinationCopy(MachineBasicBlock & MBB,MachineBasicBlock::iterator LastPHIIt,const DebugLoc & DL,Register Src,Register Dst) const6561 MachineInstr *SIInstrInfo::createPHIDestinationCopy(
6562     MachineBasicBlock &MBB, MachineBasicBlock::iterator LastPHIIt,
6563     const DebugLoc &DL, Register Src, Register Dst) const {
6564   auto Cur = MBB.begin();
6565   if (Cur != MBB.end())
6566     do {
6567       if (!Cur->isPHI() && Cur->readsRegister(Dst))
6568         return BuildMI(MBB, Cur, DL, get(TargetOpcode::COPY), Dst).addReg(Src);
6569       ++Cur;
6570     } while (Cur != MBB.end() && Cur != LastPHIIt);
6571 
6572   return TargetInstrInfo::createPHIDestinationCopy(MBB, LastPHIIt, DL, Src,
6573                                                    Dst);
6574 }
6575 
createPHISourceCopy(MachineBasicBlock & MBB,MachineBasicBlock::iterator InsPt,const DebugLoc & DL,Register Src,unsigned SrcSubReg,Register Dst) const6576 MachineInstr *SIInstrInfo::createPHISourceCopy(
6577     MachineBasicBlock &MBB, MachineBasicBlock::iterator InsPt,
6578     const DebugLoc &DL, Register Src, unsigned SrcSubReg, Register Dst) const {
6579   if (InsPt != MBB.end() &&
6580       (InsPt->getOpcode() == AMDGPU::SI_IF ||
6581        InsPt->getOpcode() == AMDGPU::SI_ELSE ||
6582        InsPt->getOpcode() == AMDGPU::SI_IF_BREAK) &&
6583       InsPt->definesRegister(Src)) {
6584     InsPt++;
6585     return BuildMI(MBB, InsPt, DL,
6586                    get(ST.isWave32() ? AMDGPU::S_MOV_B32_term
6587                                      : AMDGPU::S_MOV_B64_term),
6588                    Dst)
6589         .addReg(Src, 0, SrcSubReg)
6590         .addReg(AMDGPU::EXEC, RegState::Implicit);
6591   }
6592   return TargetInstrInfo::createPHISourceCopy(MBB, InsPt, DL, Src, SrcSubReg,
6593                                               Dst);
6594 }
6595 
isWave32() const6596 bool llvm::SIInstrInfo::isWave32() const { return ST.isWave32(); }
6597 
foldMemoryOperandImpl(MachineFunction & MF,MachineInstr & MI,ArrayRef<unsigned> Ops,MachineBasicBlock::iterator InsertPt,int FrameIndex,LiveIntervals * LIS,VirtRegMap * VRM) const6598 MachineInstr *SIInstrInfo::foldMemoryOperandImpl(
6599     MachineFunction &MF, MachineInstr &MI, ArrayRef<unsigned> Ops,
6600     MachineBasicBlock::iterator InsertPt, int FrameIndex, LiveIntervals *LIS,
6601     VirtRegMap *VRM) const {
6602   // This is a bit of a hack (copied from AArch64). Consider this instruction:
6603   //
6604   //   %0:sreg_32 = COPY $m0
6605   //
6606   // We explicitly chose SReg_32 for the virtual register so such a copy might
6607   // be eliminated by RegisterCoalescer. However, that may not be possible, and
6608   // %0 may even spill. We can't spill $m0 normally (it would require copying to
6609   // a numbered SGPR anyway), and since it is in the SReg_32 register class,
6610   // TargetInstrInfo::foldMemoryOperand() is going to try.
6611   //
6612   // To prevent that, constrain the %0 register class here.
6613   if (MI.isFullCopy()) {
6614     Register DstReg = MI.getOperand(0).getReg();
6615     Register SrcReg = MI.getOperand(1).getReg();
6616 
6617     if (DstReg == AMDGPU::M0 && SrcReg.isVirtual()) {
6618       MF.getRegInfo().constrainRegClass(SrcReg, &AMDGPU::SReg_32_XM0RegClass);
6619       return nullptr;
6620     }
6621 
6622     if (SrcReg == AMDGPU::M0 && DstReg.isVirtual()) {
6623       MF.getRegInfo().constrainRegClass(DstReg, &AMDGPU::SReg_32_XM0RegClass);
6624       return nullptr;
6625     }
6626   }
6627 
6628   return nullptr;
6629 }
6630 
getInstrLatency(const InstrItineraryData * ItinData,const MachineInstr & MI,unsigned * PredCost) const6631 unsigned SIInstrInfo::getInstrLatency(const InstrItineraryData *ItinData,
6632                                       const MachineInstr &MI,
6633                                       unsigned *PredCost) const {
6634   if (MI.isBundle()) {
6635     MachineBasicBlock::const_instr_iterator I(MI.getIterator());
6636     MachineBasicBlock::const_instr_iterator E(MI.getParent()->instr_end());
6637     unsigned Lat = 0, Count = 0;
6638     for (++I; I != E && I->isBundledWithPred(); ++I) {
6639       ++Count;
6640       Lat = std::max(Lat, SchedModel.computeInstrLatency(&*I));
6641     }
6642     return Lat + Count - 1;
6643   }
6644 
6645   return SchedModel.computeInstrLatency(&MI);
6646 }
6647