xref: /llvm-project/llvm/lib/Target/Sparc/Disassembler/SparcDisassembler.cpp (revision 829b104dc28d0982b86245790adf335eed598b0c)
1 //===- SparcDisassembler.cpp - Disassembler for Sparc -----------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file is part of the Sparc Disassembler.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "Sparc.h"
15 #include "SparcRegisterInfo.h"
16 #include "SparcSubtarget.h"
17 #include "llvm/MC/MCDisassembler/MCDisassembler.h"
18 #include "llvm/MC/MCFixedLenDisassembler.h"
19 #include "llvm/MC/MCInst.h"
20 #include "llvm/MC/MCContext.h"
21 #include "llvm/MC/MCAsmInfo.h"
22 #include "llvm/Support/TargetRegistry.h"
23 
24 using namespace llvm;
25 
26 #define DEBUG_TYPE "sparc-disassembler"
27 
28 typedef MCDisassembler::DecodeStatus DecodeStatus;
29 
30 namespace {
31 
32 /// A disassembler class for Sparc.
33 class SparcDisassembler : public MCDisassembler {
34 public:
35   SparcDisassembler(const MCSubtargetInfo &STI, MCContext &Ctx)
36       : MCDisassembler(STI, Ctx) {}
37   virtual ~SparcDisassembler() {}
38 
39   DecodeStatus getInstruction(MCInst &Instr, uint64_t &Size,
40                               ArrayRef<uint8_t> Bytes, uint64_t Address,
41                               raw_ostream &VStream,
42                               raw_ostream &CStream) const override;
43 };
44 }
45 
46 namespace llvm {
47 extern Target TheSparcTarget, TheSparcV9Target, TheSparcelTarget;
48 }
49 
50 static MCDisassembler *createSparcDisassembler(const Target &T,
51                                                const MCSubtargetInfo &STI,
52                                                MCContext &Ctx) {
53   return new SparcDisassembler(STI, Ctx);
54 }
55 
56 
57 extern "C" void LLVMInitializeSparcDisassembler() {
58   // Register the disassembler.
59   TargetRegistry::RegisterMCDisassembler(TheSparcTarget,
60                                          createSparcDisassembler);
61   TargetRegistry::RegisterMCDisassembler(TheSparcV9Target,
62                                          createSparcDisassembler);
63   TargetRegistry::RegisterMCDisassembler(TheSparcelTarget,
64                                          createSparcDisassembler);
65 }
66 
67 static const unsigned IntRegDecoderTable[] = {
68   SP::G0,  SP::G1,  SP::G2,  SP::G3,
69   SP::G4,  SP::G5,  SP::G6,  SP::G7,
70   SP::O0,  SP::O1,  SP::O2,  SP::O3,
71   SP::O4,  SP::O5,  SP::O6,  SP::O7,
72   SP::L0,  SP::L1,  SP::L2,  SP::L3,
73   SP::L4,  SP::L5,  SP::L6,  SP::L7,
74   SP::I0,  SP::I1,  SP::I2,  SP::I3,
75   SP::I4,  SP::I5,  SP::I6,  SP::I7 };
76 
77 static const unsigned FPRegDecoderTable[] = {
78   SP::F0,   SP::F1,   SP::F2,   SP::F3,
79   SP::F4,   SP::F5,   SP::F6,   SP::F7,
80   SP::F8,   SP::F9,   SP::F10,  SP::F11,
81   SP::F12,  SP::F13,  SP::F14,  SP::F15,
82   SP::F16,  SP::F17,  SP::F18,  SP::F19,
83   SP::F20,  SP::F21,  SP::F22,  SP::F23,
84   SP::F24,  SP::F25,  SP::F26,  SP::F27,
85   SP::F28,  SP::F29,  SP::F30,  SP::F31 };
86 
87 static const unsigned DFPRegDecoderTable[] = {
88   SP::D0,   SP::D16,  SP::D1,   SP::D17,
89   SP::D2,   SP::D18,  SP::D3,   SP::D19,
90   SP::D4,   SP::D20,  SP::D5,   SP::D21,
91   SP::D6,   SP::D22,  SP::D7,   SP::D23,
92   SP::D8,   SP::D24,  SP::D9,   SP::D25,
93   SP::D10,  SP::D26,  SP::D11,  SP::D27,
94   SP::D12,  SP::D28,  SP::D13,  SP::D29,
95   SP::D14,  SP::D30,  SP::D15,  SP::D31 };
96 
97 static const unsigned QFPRegDecoderTable[] = {
98   SP::Q0,  SP::Q8,   ~0U,  ~0U,
99   SP::Q1,  SP::Q9,   ~0U,  ~0U,
100   SP::Q2,  SP::Q10,  ~0U,  ~0U,
101   SP::Q3,  SP::Q11,  ~0U,  ~0U,
102   SP::Q4,  SP::Q12,  ~0U,  ~0U,
103   SP::Q5,  SP::Q13,  ~0U,  ~0U,
104   SP::Q6,  SP::Q14,  ~0U,  ~0U,
105   SP::Q7,  SP::Q15,  ~0U,  ~0U } ;
106 
107 static const unsigned FCCRegDecoderTable[] = {
108   SP::FCC0, SP::FCC1, SP::FCC2, SP::FCC3 };
109 
110 static const unsigned ASRRegDecoderTable[] = {
111   SP::Y,     SP::ASR1,  SP::ASR2,  SP::ASR3,
112   SP::ASR4,  SP::ASR5,  SP::ASR6,  SP::ASR7,
113   SP::ASR8,  SP::ASR9,  SP::ASR10, SP::ASR11,
114   SP::ASR12, SP::ASR13, SP::ASR14, SP::ASR15,
115   SP::ASR16, SP::ASR17, SP::ASR18, SP::ASR19,
116   SP::ASR20, SP::ASR21, SP::ASR22, SP::ASR23,
117   SP::ASR24, SP::ASR25, SP::ASR26, SP::ASR27,
118   SP::ASR28, SP::ASR29, SP::ASR30, SP::ASR31};
119 
120 static const unsigned PRRegDecoderTable[] = {
121   SP::TPC, SP::TNPC, SP::TSTATE, SP::TT, SP::TICK, SP::TBA, SP::PSTATE,
122   SP::TL, SP::PIL, SP::CWP, SP::CANSAVE, SP::CANRESTORE, SP::CLEANWIN,
123   SP::OTHERWIN, SP::WSTATE
124 };
125 
126 static const uint16_t IntPairDecoderTable[] = {
127   SP::G0_G1, SP::G2_G3, SP::G4_G5, SP::G6_G7,
128   SP::O0_O1, SP::O2_O3, SP::O4_O5, SP::O6_O7,
129   SP::L0_L1, SP::L2_L3, SP::L4_L5, SP::L6_L7,
130   SP::I0_I1, SP::I2_I3, SP::I4_I5, SP::I6_I7,
131 };
132 
133 static DecodeStatus DecodeIntRegsRegisterClass(MCInst &Inst,
134                                                unsigned RegNo,
135                                                uint64_t Address,
136                                                const void *Decoder) {
137   if (RegNo > 31)
138     return MCDisassembler::Fail;
139   unsigned Reg = IntRegDecoderTable[RegNo];
140   Inst.addOperand(MCOperand::createReg(Reg));
141   return MCDisassembler::Success;
142 }
143 
144 static DecodeStatus DecodeI64RegsRegisterClass(MCInst &Inst,
145                                                unsigned RegNo,
146                                                uint64_t Address,
147                                                const void *Decoder) {
148   if (RegNo > 31)
149     return MCDisassembler::Fail;
150   unsigned Reg = IntRegDecoderTable[RegNo];
151   Inst.addOperand(MCOperand::createReg(Reg));
152   return MCDisassembler::Success;
153 }
154 
155 
156 static DecodeStatus DecodeFPRegsRegisterClass(MCInst &Inst,
157                                               unsigned RegNo,
158                                               uint64_t Address,
159                                               const void *Decoder) {
160   if (RegNo > 31)
161     return MCDisassembler::Fail;
162   unsigned Reg = FPRegDecoderTable[RegNo];
163   Inst.addOperand(MCOperand::createReg(Reg));
164   return MCDisassembler::Success;
165 }
166 
167 
168 static DecodeStatus DecodeDFPRegsRegisterClass(MCInst &Inst,
169                                                unsigned RegNo,
170                                                uint64_t Address,
171                                                const void *Decoder) {
172   if (RegNo > 31)
173     return MCDisassembler::Fail;
174   unsigned Reg = DFPRegDecoderTable[RegNo];
175   Inst.addOperand(MCOperand::createReg(Reg));
176   return MCDisassembler::Success;
177 }
178 
179 
180 static DecodeStatus DecodeQFPRegsRegisterClass(MCInst &Inst,
181                                                unsigned RegNo,
182                                                uint64_t Address,
183                                                const void *Decoder) {
184   if (RegNo > 31)
185     return MCDisassembler::Fail;
186 
187   unsigned Reg = QFPRegDecoderTable[RegNo];
188   if (Reg == ~0U)
189     return MCDisassembler::Fail;
190   Inst.addOperand(MCOperand::createReg(Reg));
191   return MCDisassembler::Success;
192 }
193 
194 static DecodeStatus DecodeFCCRegsRegisterClass(MCInst &Inst, unsigned RegNo,
195                                                uint64_t Address,
196                                                const void *Decoder) {
197   if (RegNo > 3)
198     return MCDisassembler::Fail;
199   Inst.addOperand(MCOperand::createReg(FCCRegDecoderTable[RegNo]));
200   return MCDisassembler::Success;
201 }
202 
203 static DecodeStatus DecodeASRRegsRegisterClass(MCInst &Inst, unsigned RegNo,
204                                                uint64_t Address,
205                                                const void *Decoder) {
206   if (RegNo > 31)
207     return MCDisassembler::Fail;
208   Inst.addOperand(MCOperand::createReg(ASRRegDecoderTable[RegNo]));
209   return MCDisassembler::Success;
210 }
211 
212 static DecodeStatus DecodePRRegsRegisterClass(MCInst &Inst, unsigned RegNo,
213                                                uint64_t Address,
214                                                const void *Decoder) {
215   if (RegNo >= array_lengthof(PRRegDecoderTable))
216     return MCDisassembler::Fail;
217   Inst.addOperand(MCOperand::createReg(PRRegDecoderTable[RegNo]));
218   return MCDisassembler::Success;
219 }
220 
221 static DecodeStatus DecodeIntPairRegisterClass(MCInst &Inst, unsigned RegNo,
222                                    uint64_t Address, const void *Decoder) {
223   DecodeStatus S = MCDisassembler::Success;
224 
225   if (RegNo > 31)
226     return MCDisassembler::Fail;
227 
228   if ((RegNo & 1))
229     S = MCDisassembler::SoftFail;
230 
231   unsigned RegisterPair = IntPairDecoderTable[RegNo/2];
232   Inst.addOperand(MCOperand::createReg(RegisterPair));
233   return S;
234 }
235 
236 static DecodeStatus DecodeLoadInt(MCInst &Inst, unsigned insn, uint64_t Address,
237                                   const void *Decoder);
238 static DecodeStatus DecodeLoadIntPair(MCInst &Inst, unsigned insn, uint64_t Address,
239                                   const void *Decoder);
240 static DecodeStatus DecodeLoadFP(MCInst &Inst, unsigned insn, uint64_t Address,
241                                  const void *Decoder);
242 static DecodeStatus DecodeLoadDFP(MCInst &Inst, unsigned insn, uint64_t Address,
243                                   const void *Decoder);
244 static DecodeStatus DecodeLoadQFP(MCInst &Inst, unsigned insn, uint64_t Address,
245                                   const void *Decoder);
246 static DecodeStatus DecodeStoreInt(MCInst &Inst, unsigned insn,
247                                    uint64_t Address, const void *Decoder);
248 static DecodeStatus DecodeStoreIntPair(MCInst &Inst, unsigned insn,
249                                    uint64_t Address, const void *Decoder);
250 static DecodeStatus DecodeStoreFP(MCInst &Inst, unsigned insn,
251                                   uint64_t Address, const void *Decoder);
252 static DecodeStatus DecodeStoreDFP(MCInst &Inst, unsigned insn,
253                                    uint64_t Address, const void *Decoder);
254 static DecodeStatus DecodeStoreQFP(MCInst &Inst, unsigned insn,
255                                    uint64_t Address, const void *Decoder);
256 static DecodeStatus DecodeCall(MCInst &Inst, unsigned insn,
257                                uint64_t Address, const void *Decoder);
258 static DecodeStatus DecodeSIMM13(MCInst &Inst, unsigned insn,
259                                  uint64_t Address, const void *Decoder);
260 static DecodeStatus DecodeJMPL(MCInst &Inst, unsigned insn, uint64_t Address,
261                                const void *Decoder);
262 static DecodeStatus DecodeReturn(MCInst &MI, unsigned insn, uint64_t Address,
263                                  const void *Decoder);
264 static DecodeStatus DecodeSWAP(MCInst &Inst, unsigned insn, uint64_t Address,
265                                const void *Decoder);
266 
267 #include "SparcGenDisassemblerTables.inc"
268 
269 /// Read four bytes from the ArrayRef and return 32 bit word.
270 static DecodeStatus readInstruction32(ArrayRef<uint8_t> Bytes, uint64_t Address,
271                                       uint64_t &Size, uint32_t &Insn,
272                                       bool IsLittleEndian) {
273   // We want to read exactly 4 Bytes of data.
274   if (Bytes.size() < 4) {
275     Size = 0;
276     return MCDisassembler::Fail;
277   }
278 
279   Insn = IsLittleEndian
280              ? (Bytes[0] << 0) | (Bytes[1] << 8) | (Bytes[2] << 16) |
281                    (Bytes[3] << 24)
282              : (Bytes[3] << 0) | (Bytes[2] << 8) | (Bytes[1] << 16) |
283                    (Bytes[0] << 24);
284 
285   return MCDisassembler::Success;
286 }
287 
288 DecodeStatus SparcDisassembler::getInstruction(MCInst &Instr, uint64_t &Size,
289                                                ArrayRef<uint8_t> Bytes,
290                                                uint64_t Address,
291                                                raw_ostream &VStream,
292                                                raw_ostream &CStream) const {
293   uint32_t Insn;
294   bool isLittleEndian = getContext().getAsmInfo()->isLittleEndian();
295   DecodeStatus Result =
296       readInstruction32(Bytes, Address, Size, Insn, isLittleEndian);
297   if (Result == MCDisassembler::Fail)
298     return MCDisassembler::Fail;
299 
300   // Calling the auto-generated decoder function.
301   Result =
302       decodeInstruction(DecoderTableSparc32, Instr, Insn, Address, this, STI);
303 
304   if (Result != MCDisassembler::Fail) {
305     Size = 4;
306     return Result;
307   }
308 
309   return MCDisassembler::Fail;
310 }
311 
312 
313 typedef DecodeStatus (*DecodeFunc)(MCInst &MI, unsigned insn, uint64_t Address,
314                                    const void *Decoder);
315 
316 static DecodeStatus DecodeMem(MCInst &MI, unsigned insn, uint64_t Address,
317                               const void *Decoder,
318                               bool isLoad, DecodeFunc DecodeRD) {
319   unsigned rd = fieldFromInstruction(insn, 25, 5);
320   unsigned rs1 = fieldFromInstruction(insn, 14, 5);
321   bool isImm = fieldFromInstruction(insn, 13, 1);
322   bool hasAsi = fieldFromInstruction(insn, 23, 1); // (in op3 field)
323   unsigned asi = fieldFromInstruction(insn, 5, 8);
324   unsigned rs2 = 0;
325   unsigned simm13 = 0;
326   if (isImm)
327     simm13 = SignExtend32<13>(fieldFromInstruction(insn, 0, 13));
328   else
329     rs2 = fieldFromInstruction(insn, 0, 5);
330 
331   DecodeStatus status;
332   if (isLoad) {
333     status = DecodeRD(MI, rd, Address, Decoder);
334     if (status != MCDisassembler::Success)
335       return status;
336   }
337 
338   // Decode rs1.
339   status = DecodeIntRegsRegisterClass(MI, rs1, Address, Decoder);
340   if (status != MCDisassembler::Success)
341     return status;
342 
343   // Decode imm|rs2.
344   if (isImm)
345     MI.addOperand(MCOperand::createImm(simm13));
346   else {
347     status = DecodeIntRegsRegisterClass(MI, rs2, Address, Decoder);
348     if (status != MCDisassembler::Success)
349       return status;
350   }
351 
352   if (hasAsi)
353     MI.addOperand(MCOperand::createImm(asi));
354 
355   if (!isLoad) {
356     status = DecodeRD(MI, rd, Address, Decoder);
357     if (status != MCDisassembler::Success)
358       return status;
359   }
360   return MCDisassembler::Success;
361 }
362 
363 static DecodeStatus DecodeLoadInt(MCInst &Inst, unsigned insn, uint64_t Address,
364                                   const void *Decoder) {
365   return DecodeMem(Inst, insn, Address, Decoder, true,
366                    DecodeIntRegsRegisterClass);
367 }
368 
369 static DecodeStatus DecodeLoadIntPair(MCInst &Inst, unsigned insn, uint64_t Address,
370                                   const void *Decoder) {
371   return DecodeMem(Inst, insn, Address, Decoder, true,
372                    DecodeIntPairRegisterClass);
373 }
374 
375 static DecodeStatus DecodeLoadFP(MCInst &Inst, unsigned insn, uint64_t Address,
376                                  const void *Decoder) {
377   return DecodeMem(Inst, insn, Address, Decoder, true,
378                    DecodeFPRegsRegisterClass);
379 }
380 
381 static DecodeStatus DecodeLoadDFP(MCInst &Inst, unsigned insn, uint64_t Address,
382                                   const void *Decoder) {
383   return DecodeMem(Inst, insn, Address, Decoder, true,
384                    DecodeDFPRegsRegisterClass);
385 }
386 
387 static DecodeStatus DecodeLoadQFP(MCInst &Inst, unsigned insn, uint64_t Address,
388                                   const void *Decoder) {
389   return DecodeMem(Inst, insn, Address, Decoder, true,
390                    DecodeQFPRegsRegisterClass);
391 }
392 
393 static DecodeStatus DecodeStoreInt(MCInst &Inst, unsigned insn,
394                                    uint64_t Address, const void *Decoder) {
395   return DecodeMem(Inst, insn, Address, Decoder, false,
396                    DecodeIntRegsRegisterClass);
397 }
398 
399 static DecodeStatus DecodeStoreIntPair(MCInst &Inst, unsigned insn,
400                                    uint64_t Address, const void *Decoder) {
401   return DecodeMem(Inst, insn, Address, Decoder, false,
402                    DecodeIntPairRegisterClass);
403 }
404 
405 static DecodeStatus DecodeStoreFP(MCInst &Inst, unsigned insn, uint64_t Address,
406                                   const void *Decoder) {
407   return DecodeMem(Inst, insn, Address, Decoder, false,
408                    DecodeFPRegsRegisterClass);
409 }
410 
411 static DecodeStatus DecodeStoreDFP(MCInst &Inst, unsigned insn,
412                                    uint64_t Address, const void *Decoder) {
413   return DecodeMem(Inst, insn, Address, Decoder, false,
414                    DecodeDFPRegsRegisterClass);
415 }
416 
417 static DecodeStatus DecodeStoreQFP(MCInst &Inst, unsigned insn,
418                                    uint64_t Address, const void *Decoder) {
419   return DecodeMem(Inst, insn, Address, Decoder, false,
420                    DecodeQFPRegsRegisterClass);
421 }
422 
423 static bool tryAddingSymbolicOperand(int64_t Value,  bool isBranch,
424                                      uint64_t Address, uint64_t Offset,
425                                      uint64_t Width, MCInst &MI,
426                                      const void *Decoder) {
427   const MCDisassembler *Dis = static_cast<const MCDisassembler*>(Decoder);
428   return Dis->tryAddingSymbolicOperand(MI, Value, Address, isBranch,
429                                        Offset, Width);
430 }
431 
432 static DecodeStatus DecodeCall(MCInst &MI, unsigned insn,
433                                uint64_t Address, const void *Decoder) {
434   unsigned tgt = fieldFromInstruction(insn, 0, 30);
435   tgt <<= 2;
436   if (!tryAddingSymbolicOperand(tgt+Address, false, Address,
437                                 0, 30, MI, Decoder))
438     MI.addOperand(MCOperand::createImm(tgt));
439   return MCDisassembler::Success;
440 }
441 
442 static DecodeStatus DecodeSIMM13(MCInst &MI, unsigned insn,
443                                  uint64_t Address, const void *Decoder) {
444   unsigned tgt = SignExtend32<13>(fieldFromInstruction(insn, 0, 13));
445   MI.addOperand(MCOperand::createImm(tgt));
446   return MCDisassembler::Success;
447 }
448 
449 static DecodeStatus DecodeJMPL(MCInst &MI, unsigned insn, uint64_t Address,
450                                const void *Decoder) {
451 
452   unsigned rd = fieldFromInstruction(insn, 25, 5);
453   unsigned rs1 = fieldFromInstruction(insn, 14, 5);
454   unsigned isImm = fieldFromInstruction(insn, 13, 1);
455   unsigned rs2 = 0;
456   unsigned simm13 = 0;
457   if (isImm)
458     simm13 = SignExtend32<13>(fieldFromInstruction(insn, 0, 13));
459   else
460     rs2 = fieldFromInstruction(insn, 0, 5);
461 
462   // Decode RD.
463   DecodeStatus status = DecodeIntRegsRegisterClass(MI, rd, Address, Decoder);
464   if (status != MCDisassembler::Success)
465     return status;
466 
467   // Decode RS1.
468   status = DecodeIntRegsRegisterClass(MI, rs1, Address, Decoder);
469   if (status != MCDisassembler::Success)
470     return status;
471 
472   // Decode RS1 | SIMM13.
473   if (isImm)
474     MI.addOperand(MCOperand::createImm(simm13));
475   else {
476     status = DecodeIntRegsRegisterClass(MI, rs2, Address, Decoder);
477     if (status != MCDisassembler::Success)
478       return status;
479   }
480   return MCDisassembler::Success;
481 }
482 
483 static DecodeStatus DecodeReturn(MCInst &MI, unsigned insn, uint64_t Address,
484                                  const void *Decoder) {
485 
486   unsigned rs1 = fieldFromInstruction(insn, 14, 5);
487   unsigned isImm = fieldFromInstruction(insn, 13, 1);
488   unsigned rs2 = 0;
489   unsigned simm13 = 0;
490   if (isImm)
491     simm13 = SignExtend32<13>(fieldFromInstruction(insn, 0, 13));
492   else
493     rs2 = fieldFromInstruction(insn, 0, 5);
494 
495   // Decode RS1.
496   DecodeStatus status = DecodeIntRegsRegisterClass(MI, rs1, Address, Decoder);
497   if (status != MCDisassembler::Success)
498     return status;
499 
500   // Decode RS2 | SIMM13.
501   if (isImm)
502     MI.addOperand(MCOperand::createImm(simm13));
503   else {
504     status = DecodeIntRegsRegisterClass(MI, rs2, Address, Decoder);
505     if (status != MCDisassembler::Success)
506       return status;
507   }
508   return MCDisassembler::Success;
509 }
510 
511 static DecodeStatus DecodeSWAP(MCInst &MI, unsigned insn, uint64_t Address,
512                                const void *Decoder) {
513 
514   unsigned rd = fieldFromInstruction(insn, 25, 5);
515   unsigned rs1 = fieldFromInstruction(insn, 14, 5);
516   unsigned isImm = fieldFromInstruction(insn, 13, 1);
517   bool hasAsi = fieldFromInstruction(insn, 23, 1); // (in op3 field)
518   unsigned asi = fieldFromInstruction(insn, 5, 8);
519   unsigned rs2 = 0;
520   unsigned simm13 = 0;
521   if (isImm)
522     simm13 = SignExtend32<13>(fieldFromInstruction(insn, 0, 13));
523   else
524     rs2 = fieldFromInstruction(insn, 0, 5);
525 
526   // Decode RD.
527   DecodeStatus status = DecodeIntRegsRegisterClass(MI, rd, Address, Decoder);
528   if (status != MCDisassembler::Success)
529     return status;
530 
531   // Decode RS1.
532   status = DecodeIntRegsRegisterClass(MI, rs1, Address, Decoder);
533   if (status != MCDisassembler::Success)
534     return status;
535 
536   // Decode RS1 | SIMM13.
537   if (isImm)
538     MI.addOperand(MCOperand::createImm(simm13));
539   else {
540     status = DecodeIntRegsRegisterClass(MI, rs2, Address, Decoder);
541     if (status != MCDisassembler::Success)
542       return status;
543   }
544 
545   if (hasAsi)
546     MI.addOperand(MCOperand::createImm(asi));
547 
548   return MCDisassembler::Success;
549 }
550