1 //===-- HexagonDisassembler.cpp - Disassembler for Hexagon ISA ------------===//
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 #define DEBUG_TYPE "hexagon-disassembler"
11 
12 #include "Hexagon.h"
13 #include "MCTargetDesc/HexagonBaseInfo.h"
14 #include "MCTargetDesc/HexagonMCChecker.h"
15 #include "MCTargetDesc/HexagonMCInstrInfo.h"
16 #include "MCTargetDesc/HexagonMCTargetDesc.h"
17 #include "llvm/ADT/ArrayRef.h"
18 #include "llvm/ADT/STLExtras.h"
19 #include "llvm/MC/MCContext.h"
20 #include "llvm/MC/MCDisassembler/MCDisassembler.h"
21 #include "llvm/MC/MCExpr.h"
22 #include "llvm/MC/MCFixedLenDisassembler.h"
23 #include "llvm/MC/MCInst.h"
24 #include "llvm/MC/MCInstrInfo.h"
25 #include "llvm/MC/MCRegisterInfo.h"
26 #include "llvm/MC/MCSubtargetInfo.h"
27 #include "llvm/Support/MathExtras.h"
28 #include "llvm/Support/TargetRegistry.h"
29 #include "llvm/Support/raw_ostream.h"
30 #include <cassert>
31 #include <cstddef>
32 #include <cstdint>
33 #include <memory>
34 
35 using namespace llvm;
36 using namespace Hexagon;
37 
38 typedef MCDisassembler::DecodeStatus DecodeStatus;
39 
40 namespace {
41 
42 /// \brief Hexagon disassembler for all Hexagon platforms.
43 class HexagonDisassembler : public MCDisassembler {
44 public:
45   std::unique_ptr<MCInstrInfo const> const MCII;
46   std::unique_ptr<MCInst *> CurrentBundle;
47 
48   HexagonDisassembler(const MCSubtargetInfo &STI, MCContext &Ctx,
49                       MCInstrInfo const *MCII)
50       : MCDisassembler(STI, Ctx), MCII(MCII), CurrentBundle(new MCInst *) {}
51 
52   DecodeStatus getSingleInstruction(MCInst &Instr, MCInst &MCB,
53                                     ArrayRef<uint8_t> Bytes, uint64_t Address,
54                                     raw_ostream &VStream, raw_ostream &CStream,
55                                     bool &Complete) const;
56   DecodeStatus getInstruction(MCInst &Instr, uint64_t &Size,
57                               ArrayRef<uint8_t> Bytes, uint64_t Address,
58                               raw_ostream &VStream,
59                               raw_ostream &CStream) const override;
60   void addSubinstOperands(MCInst *MI, unsigned opcode, unsigned inst) const;
61 };
62 
63 namespace {
64   uint32_t fullValue(MCInstrInfo const &MCII, MCInst &MCB, MCInst &MI,
65                      int64_t Value) {
66     MCInst const *Extender = HexagonMCInstrInfo::extenderForIndex(
67       MCB, HexagonMCInstrInfo::bundleSize(MCB));
68     if (!Extender || MI.size() != HexagonMCInstrInfo::getExtendableOp(MCII, MI))
69       return Value;
70     unsigned Alignment = HexagonMCInstrInfo::getExtentAlignment(MCII, MI);
71     uint32_t Lower6 = static_cast<uint32_t>(Value >> Alignment) & 0x3f;
72     int64_t Bits;
73     bool Success = Extender->getOperand(0).getExpr()->evaluateAsAbsolute(Bits);
74     assert(Success); (void)Success;
75     uint32_t Upper26 = static_cast<uint32_t>(Bits);
76     uint32_t Operand = Upper26 | Lower6;
77     return Operand;
78   }
79   HexagonDisassembler const &disassembler(void const *Decoder) {
80     return *static_cast<HexagonDisassembler const *>(Decoder);
81   }
82   template <size_t T>
83   void signedDecoder(MCInst &MI, unsigned tmp, const void *Decoder) {
84     HexagonDisassembler const &Disassembler = disassembler(Decoder);
85     int64_t FullValue =
86         fullValue(*Disassembler.MCII, **Disassembler.CurrentBundle, MI,
87                   SignExtend64<T>(tmp));
88     int64_t Extended = SignExtend64<32>(FullValue);
89     HexagonMCInstrInfo::addConstant(MI, Extended, Disassembler.getContext());
90   }
91 }
92 } // end anonymous namespace
93 
94 // Forward declare these because the auto-generated code will reference them.
95 // Definitions are further down.
96 
97 static DecodeStatus DecodeIntRegsRegisterClass(MCInst &Inst, unsigned RegNo,
98                                                uint64_t Address,
99                                                const void *Decoder);
100 static DecodeStatus DecodeGeneralSubRegsRegisterClass(MCInst &Inst,
101                                                       unsigned RegNo,
102                                                       uint64_t Address,
103                                                       const void *Decoder);
104 static DecodeStatus DecodeIntRegsLow8RegisterClass(MCInst &Inst, unsigned RegNo,
105                                                    uint64_t Address,
106                                                    const void *Decoder);
107 static DecodeStatus DecodeVectorRegsRegisterClass(MCInst &Inst, unsigned RegNo,
108                                                   uint64_t Address,
109                                                   const void *Decoder);
110 static DecodeStatus DecodeDoubleRegsRegisterClass(MCInst &Inst, unsigned RegNo,
111                                                   uint64_t Address,
112                                                   const void *Decoder);
113 static DecodeStatus
114 DecodeGeneralDoubleLow8RegsRegisterClass(MCInst &Inst, unsigned RegNo,
115                                          uint64_t Address, const void *Decoder);
116 static DecodeStatus DecodeVecDblRegsRegisterClass(MCInst &Inst, unsigned RegNo,
117                                                   uint64_t Address,
118                                                   const void *Decoder);
119 static DecodeStatus DecodePredRegsRegisterClass(MCInst &Inst, unsigned RegNo,
120                                                 uint64_t Address,
121                                                 const void *Decoder);
122 static DecodeStatus DecodeVecPredRegsRegisterClass(MCInst &Inst, unsigned RegNo,
123                                                    uint64_t Address,
124                                                    const void *Decoder);
125 static DecodeStatus DecodeCtrRegsRegisterClass(MCInst &Inst, unsigned RegNo,
126                                                uint64_t Address,
127                                                const void *Decoder);
128 static DecodeStatus DecodeModRegsRegisterClass(MCInst &Inst, unsigned RegNo,
129                                                uint64_t Address,
130                                                const void *Decoder);
131 static DecodeStatus DecodeCtrRegs64RegisterClass(MCInst &Inst, unsigned RegNo,
132                                                  uint64_t Address,
133                                                  const void *Decoder);
134 
135 static DecodeStatus unsignedImmDecoder(MCInst &MI, unsigned tmp,
136                                        uint64_t Address, const void *Decoder);
137 static DecodeStatus s32_0ImmDecoder(MCInst &MI, unsigned tmp,
138                                     uint64_t /*Address*/, const void *Decoder);
139 static DecodeStatus s8_0ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
140                                  const void *Decoder);
141 static DecodeStatus s6_0ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
142                                    const void *Decoder);
143 static DecodeStatus s4_0ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
144                                    const void *Decoder);
145 static DecodeStatus s4_1ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
146                                    const void *Decoder);
147 static DecodeStatus s4_2ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
148                                    const void *Decoder);
149 static DecodeStatus s4_3ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
150                                    const void *Decoder);
151 static DecodeStatus s3_0ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
152                                    const void *Decoder);
153 static DecodeStatus brtargetDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
154                                     const void *Decoder);
155 
156 #include "HexagonDepDecoders.h"
157 #include "HexagonGenDisassemblerTables.inc"
158 
159 static MCDisassembler *createHexagonDisassembler(const Target &T,
160                                                  const MCSubtargetInfo &STI,
161                                                  MCContext &Ctx) {
162   return new HexagonDisassembler(STI, Ctx, T.createMCInstrInfo());
163 }
164 
165 extern "C" void LLVMInitializeHexagonDisassembler() {
166   TargetRegistry::RegisterMCDisassembler(getTheHexagonTarget(),
167                                          createHexagonDisassembler);
168 }
169 
170 DecodeStatus HexagonDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
171                                                  ArrayRef<uint8_t> Bytes,
172                                                  uint64_t Address,
173                                                  raw_ostream &os,
174                                                  raw_ostream &cs) const {
175   DecodeStatus Result = DecodeStatus::Success;
176   bool Complete = false;
177   Size = 0;
178 
179   *CurrentBundle = &MI;
180   MI = HexagonMCInstrInfo::createBundle();
181   while (Result == Success && !Complete) {
182     if (Bytes.size() < HEXAGON_INSTR_SIZE)
183       return MCDisassembler::Fail;
184     MCInst *Inst = new (getContext()) MCInst;
185     Result = getSingleInstruction(*Inst, MI, Bytes, Address, os, cs, Complete);
186     MI.addOperand(MCOperand::createInst(Inst));
187     Size += HEXAGON_INSTR_SIZE;
188     Bytes = Bytes.slice(HEXAGON_INSTR_SIZE);
189   }
190   if (Result == MCDisassembler::Fail)
191     return Result;
192   if (Size > HEXAGON_MAX_PACKET_SIZE)
193     return MCDisassembler::Fail;
194   HexagonMCChecker Checker(getContext(), *MCII, STI, MI,
195                            *getContext().getRegisterInfo(), false);
196   if (!Checker.check())
197     return MCDisassembler::Fail;
198   return MCDisassembler::Success;
199 }
200 
201 namespace {
202 void adjustDuplex(MCInst &MI, MCContext &Context) {
203   switch (MI.getOpcode()) {
204   case Hexagon::SA1_setin1:
205     MI.insert(MI.begin() + 1,
206               MCOperand::createExpr(MCConstantExpr::create(-1, Context)));
207     break;
208   case Hexagon::SA1_dec:
209     MI.insert(MI.begin() + 2,
210               MCOperand::createExpr(MCConstantExpr::create(-1, Context)));
211     break;
212   default:
213     break;
214   }
215 }
216 }
217 
218 DecodeStatus HexagonDisassembler::getSingleInstruction(
219     MCInst &MI, MCInst &MCB, ArrayRef<uint8_t> Bytes, uint64_t Address,
220     raw_ostream &os, raw_ostream &cs, bool &Complete) const {
221   assert(Bytes.size() >= HEXAGON_INSTR_SIZE);
222 
223   uint32_t Instruction = support::endian::read32le(Bytes.data());
224 
225   auto BundleSize = HexagonMCInstrInfo::bundleSize(MCB);
226   if ((Instruction & HexagonII::INST_PARSE_MASK) ==
227       HexagonII::INST_PARSE_LOOP_END) {
228     if (BundleSize == 0)
229       HexagonMCInstrInfo::setInnerLoop(MCB);
230     else if (BundleSize == 1)
231       HexagonMCInstrInfo::setOuterLoop(MCB);
232     else
233       return DecodeStatus::Fail;
234   }
235 
236   MCInst const *Extender = HexagonMCInstrInfo::extenderForIndex(
237       MCB, HexagonMCInstrInfo::bundleSize(MCB));
238 
239   DecodeStatus Result = DecodeStatus::Fail;
240   if ((Instruction & HexagonII::INST_PARSE_MASK) ==
241       HexagonII::INST_PARSE_DUPLEX) {
242     unsigned duplexIClass;
243     uint8_t const *DecodeLow, *DecodeHigh;
244     duplexIClass = ((Instruction >> 28) & 0xe) | ((Instruction >> 13) & 0x1);
245     switch (duplexIClass) {
246     default:
247       return MCDisassembler::Fail;
248     case 0:
249       DecodeLow = DecoderTableSUBINSN_L132;
250       DecodeHigh = DecoderTableSUBINSN_L132;
251       break;
252     case 1:
253       DecodeLow = DecoderTableSUBINSN_L232;
254       DecodeHigh = DecoderTableSUBINSN_L132;
255       break;
256     case 2:
257       DecodeLow = DecoderTableSUBINSN_L232;
258       DecodeHigh = DecoderTableSUBINSN_L232;
259       break;
260     case 3:
261       DecodeLow = DecoderTableSUBINSN_A32;
262       DecodeHigh = DecoderTableSUBINSN_A32;
263       break;
264     case 4:
265       DecodeLow = DecoderTableSUBINSN_L132;
266       DecodeHigh = DecoderTableSUBINSN_A32;
267       break;
268     case 5:
269       DecodeLow = DecoderTableSUBINSN_L232;
270       DecodeHigh = DecoderTableSUBINSN_A32;
271       break;
272     case 6:
273       DecodeLow = DecoderTableSUBINSN_S132;
274       DecodeHigh = DecoderTableSUBINSN_A32;
275       break;
276     case 7:
277       DecodeLow = DecoderTableSUBINSN_S232;
278       DecodeHigh = DecoderTableSUBINSN_A32;
279       break;
280     case 8:
281       DecodeLow = DecoderTableSUBINSN_S132;
282       DecodeHigh = DecoderTableSUBINSN_L132;
283       break;
284     case 9:
285       DecodeLow = DecoderTableSUBINSN_S132;
286       DecodeHigh = DecoderTableSUBINSN_L232;
287       break;
288     case 10:
289       DecodeLow = DecoderTableSUBINSN_S132;
290       DecodeHigh = DecoderTableSUBINSN_S132;
291       break;
292     case 11:
293       DecodeLow = DecoderTableSUBINSN_S232;
294       DecodeHigh = DecoderTableSUBINSN_S132;
295       break;
296     case 12:
297       DecodeLow = DecoderTableSUBINSN_S232;
298       DecodeHigh = DecoderTableSUBINSN_L132;
299       break;
300     case 13:
301       DecodeLow = DecoderTableSUBINSN_S232;
302       DecodeHigh = DecoderTableSUBINSN_L232;
303       break;
304     case 14:
305       DecodeLow = DecoderTableSUBINSN_S232;
306       DecodeHigh = DecoderTableSUBINSN_S232;
307       break;
308     }
309     MI.setOpcode(Hexagon::DuplexIClass0 + duplexIClass);
310     MCInst *MILow = new (getContext()) MCInst;
311     MCInst *MIHigh = new (getContext()) MCInst;
312     Result = decodeInstruction(DecodeLow, *MILow, Instruction & 0x1fff, Address,
313                                this, STI);
314     if (Result != DecodeStatus::Success)
315       return DecodeStatus::Fail;
316     adjustDuplex(*MILow, getContext());
317     Result = decodeInstruction(
318         DecodeHigh, *MIHigh, (Instruction >> 16) & 0x1fff, Address, this, STI);
319     if (Result != DecodeStatus::Success)
320       return DecodeStatus::Fail;
321     adjustDuplex(*MIHigh, getContext());
322     MCOperand OPLow = MCOperand::createInst(MILow);
323     MCOperand OPHigh = MCOperand::createInst(MIHigh);
324     MI.addOperand(OPLow);
325     MI.addOperand(OPHigh);
326     Complete = true;
327   } else {
328     if ((Instruction & HexagonII::INST_PARSE_MASK) ==
329         HexagonII::INST_PARSE_PACKET_END)
330       Complete = true;
331 
332     if (Extender != nullptr)
333       Result = decodeInstruction(DecoderTableMustExtend32, MI, Instruction,
334                                  Address, this, STI);
335 
336     if (Result != MCDisassembler::Success)
337       Result = decodeInstruction(DecoderTable32, MI, Instruction, Address, this,
338                                  STI);
339 
340     if (Result != MCDisassembler::Success &&
341         STI.getFeatureBits()[Hexagon::ExtensionHVX])
342       Result = decodeInstruction(DecoderTableEXT_mmvec32, MI, Instruction,
343                                  Address, this, STI);
344 
345   }
346 
347   switch (MI.getOpcode()) {
348   case Hexagon::J4_cmpeqn1_f_jumpnv_nt:
349   case Hexagon::J4_cmpeqn1_f_jumpnv_t:
350   case Hexagon::J4_cmpeqn1_fp0_jump_nt:
351   case Hexagon::J4_cmpeqn1_fp0_jump_t:
352   case Hexagon::J4_cmpeqn1_fp1_jump_nt:
353   case Hexagon::J4_cmpeqn1_fp1_jump_t:
354   case Hexagon::J4_cmpeqn1_t_jumpnv_nt:
355   case Hexagon::J4_cmpeqn1_t_jumpnv_t:
356   case Hexagon::J4_cmpeqn1_tp0_jump_nt:
357   case Hexagon::J4_cmpeqn1_tp0_jump_t:
358   case Hexagon::J4_cmpeqn1_tp1_jump_nt:
359   case Hexagon::J4_cmpeqn1_tp1_jump_t:
360   case Hexagon::J4_cmpgtn1_f_jumpnv_nt:
361   case Hexagon::J4_cmpgtn1_f_jumpnv_t:
362   case Hexagon::J4_cmpgtn1_fp0_jump_nt:
363   case Hexagon::J4_cmpgtn1_fp0_jump_t:
364   case Hexagon::J4_cmpgtn1_fp1_jump_nt:
365   case Hexagon::J4_cmpgtn1_fp1_jump_t:
366   case Hexagon::J4_cmpgtn1_t_jumpnv_nt:
367   case Hexagon::J4_cmpgtn1_t_jumpnv_t:
368   case Hexagon::J4_cmpgtn1_tp0_jump_nt:
369   case Hexagon::J4_cmpgtn1_tp0_jump_t:
370   case Hexagon::J4_cmpgtn1_tp1_jump_nt:
371   case Hexagon::J4_cmpgtn1_tp1_jump_t:
372     MI.insert(MI.begin() + 1,
373               MCOperand::createExpr(MCConstantExpr::create(-1, getContext())));
374     break;
375   default:
376     break;
377   }
378 
379   if (HexagonMCInstrInfo::isNewValue(*MCII, MI)) {
380     unsigned OpIndex = HexagonMCInstrInfo::getNewValueOp(*MCII, MI);
381     MCOperand &MCO = MI.getOperand(OpIndex);
382     assert(MCO.isReg() && "New value consumers must be registers");
383     unsigned Register =
384         getContext().getRegisterInfo()->getEncodingValue(MCO.getReg());
385     if ((Register & 0x6) == 0)
386       // HexagonPRM 10.11 Bit 1-2 == 0 is reserved
387       return MCDisassembler::Fail;
388     unsigned Lookback = (Register & 0x6) >> 1;
389     unsigned Offset = 1;
390     bool Vector = HexagonMCInstrInfo::isVector(*MCII, MI);
391     auto Instructions = HexagonMCInstrInfo::bundleInstructions(**CurrentBundle);
392     auto i = Instructions.end() - 1;
393     for (auto n = Instructions.begin() - 1;; --i, ++Offset) {
394       if (i == n)
395         // Couldn't find producer
396         return MCDisassembler::Fail;
397       if (Vector && !HexagonMCInstrInfo::isVector(*MCII, *i->getInst()))
398         // Skip scalars when calculating distances for vectors
399         ++Lookback;
400       if (HexagonMCInstrInfo::isImmext(*i->getInst()))
401         ++Lookback;
402       if (Offset == Lookback)
403         break;
404     }
405     auto const &Inst = *i->getInst();
406     bool SubregBit = (Register & 0x1) != 0;
407     if (SubregBit && HexagonMCInstrInfo::hasNewValue2(*MCII, Inst)) {
408       // If subreg bit is set we're selecting the second produced newvalue
409       unsigned Producer =
410           HexagonMCInstrInfo::getNewValueOperand2(*MCII, Inst).getReg();
411       assert(Producer != Hexagon::NoRegister);
412       MCO.setReg(Producer);
413     } else if (HexagonMCInstrInfo::hasNewValue(*MCII, Inst)) {
414       unsigned Producer =
415           HexagonMCInstrInfo::getNewValueOperand(*MCII, Inst).getReg();
416       if (Producer >= Hexagon::W0 && Producer <= Hexagon::W15)
417         Producer = ((Producer - Hexagon::W0) << 1) + SubregBit + Hexagon::V0;
418       else if (SubregBit)
419         // Hexagon PRM 10.11 New-value operands
420         // Nt[0] is reserved and should always be encoded as zero.
421         return MCDisassembler::Fail;
422       assert(Producer != Hexagon::NoRegister);
423       MCO.setReg(Producer);
424     } else
425       return MCDisassembler::Fail;
426   }
427 
428   if (Extender != nullptr) {
429     MCInst const &Inst = HexagonMCInstrInfo::isDuplex(*MCII, MI)
430                              ? *MI.getOperand(1).getInst()
431                              : MI;
432     if (!HexagonMCInstrInfo::isExtendable(*MCII, Inst) &&
433         !HexagonMCInstrInfo::isExtended(*MCII, Inst))
434       return MCDisassembler::Fail;
435   }
436   return Result;
437 }
438 
439 static DecodeStatus DecodeRegisterClass(MCInst &Inst, unsigned RegNo,
440                                         ArrayRef<MCPhysReg> Table) {
441   if (RegNo < Table.size()) {
442     Inst.addOperand(MCOperand::createReg(Table[RegNo]));
443     return MCDisassembler::Success;
444   }
445 
446   return MCDisassembler::Fail;
447 }
448 
449 static DecodeStatus DecodeIntRegsLow8RegisterClass(MCInst &Inst, unsigned RegNo,
450                                                    uint64_t Address,
451                                                    const void *Decoder) {
452   return DecodeIntRegsRegisterClass(Inst, RegNo, Address, Decoder);
453 }
454 
455 static DecodeStatus DecodeIntRegsRegisterClass(MCInst &Inst, unsigned RegNo,
456                                                uint64_t Address,
457                                                const void *Decoder) {
458   static const MCPhysReg IntRegDecoderTable[] = {
459       Hexagon::R0,  Hexagon::R1,  Hexagon::R2,  Hexagon::R3,  Hexagon::R4,
460       Hexagon::R5,  Hexagon::R6,  Hexagon::R7,  Hexagon::R8,  Hexagon::R9,
461       Hexagon::R10, Hexagon::R11, Hexagon::R12, Hexagon::R13, Hexagon::R14,
462       Hexagon::R15, Hexagon::R16, Hexagon::R17, Hexagon::R18, Hexagon::R19,
463       Hexagon::R20, Hexagon::R21, Hexagon::R22, Hexagon::R23, Hexagon::R24,
464       Hexagon::R25, Hexagon::R26, Hexagon::R27, Hexagon::R28, Hexagon::R29,
465       Hexagon::R30, Hexagon::R31};
466 
467   return DecodeRegisterClass(Inst, RegNo, IntRegDecoderTable);
468 }
469 
470 static DecodeStatus DecodeGeneralSubRegsRegisterClass(MCInst &Inst,
471                                                       unsigned RegNo,
472                                                       uint64_t Address,
473                                                       const void *Decoder) {
474   static const MCPhysReg GeneralSubRegDecoderTable[] = {
475       Hexagon::R0,  Hexagon::R1,  Hexagon::R2,  Hexagon::R3,
476       Hexagon::R4,  Hexagon::R5,  Hexagon::R6,  Hexagon::R7,
477       Hexagon::R16, Hexagon::R17, Hexagon::R18, Hexagon::R19,
478       Hexagon::R20, Hexagon::R21, Hexagon::R22, Hexagon::R23,
479   };
480 
481   return DecodeRegisterClass(Inst, RegNo, GeneralSubRegDecoderTable);
482 }
483 
484 static DecodeStatus DecodeVectorRegsRegisterClass(MCInst &Inst, unsigned RegNo,
485                                                   uint64_t /*Address*/,
486                                                   const void *Decoder) {
487   static const MCPhysReg VecRegDecoderTable[] = {
488       Hexagon::V0,  Hexagon::V1,  Hexagon::V2,  Hexagon::V3,  Hexagon::V4,
489       Hexagon::V5,  Hexagon::V6,  Hexagon::V7,  Hexagon::V8,  Hexagon::V9,
490       Hexagon::V10, Hexagon::V11, Hexagon::V12, Hexagon::V13, Hexagon::V14,
491       Hexagon::V15, Hexagon::V16, Hexagon::V17, Hexagon::V18, Hexagon::V19,
492       Hexagon::V20, Hexagon::V21, Hexagon::V22, Hexagon::V23, Hexagon::V24,
493       Hexagon::V25, Hexagon::V26, Hexagon::V27, Hexagon::V28, Hexagon::V29,
494       Hexagon::V30, Hexagon::V31};
495 
496   return DecodeRegisterClass(Inst, RegNo, VecRegDecoderTable);
497 }
498 
499 static DecodeStatus DecodeDoubleRegsRegisterClass(MCInst &Inst, unsigned RegNo,
500                                                   uint64_t /*Address*/,
501                                                   const void *Decoder) {
502   static const MCPhysReg DoubleRegDecoderTable[] = {
503       Hexagon::D0,  Hexagon::D1,  Hexagon::D2,  Hexagon::D3,
504       Hexagon::D4,  Hexagon::D5,  Hexagon::D6,  Hexagon::D7,
505       Hexagon::D8,  Hexagon::D9,  Hexagon::D10, Hexagon::D11,
506       Hexagon::D12, Hexagon::D13, Hexagon::D14, Hexagon::D15};
507 
508   return DecodeRegisterClass(Inst, RegNo >> 1, DoubleRegDecoderTable);
509 }
510 
511 static DecodeStatus DecodeGeneralDoubleLow8RegsRegisterClass(
512     MCInst &Inst, unsigned RegNo, uint64_t /*Address*/, const void *Decoder) {
513   static const MCPhysReg GeneralDoubleLow8RegDecoderTable[] = {
514       Hexagon::D0, Hexagon::D1, Hexagon::D2,  Hexagon::D3,
515       Hexagon::D8, Hexagon::D9, Hexagon::D10, Hexagon::D11};
516 
517   return DecodeRegisterClass(Inst, RegNo, GeneralDoubleLow8RegDecoderTable);
518 }
519 
520 static DecodeStatus DecodeVecDblRegsRegisterClass(MCInst &Inst, unsigned RegNo,
521                                                   uint64_t /*Address*/,
522                                                   const void *Decoder) {
523   static const MCPhysReg VecDblRegDecoderTable[] = {
524       Hexagon::W0,  Hexagon::W1,  Hexagon::W2,  Hexagon::W3,
525       Hexagon::W4,  Hexagon::W5,  Hexagon::W6,  Hexagon::W7,
526       Hexagon::W8,  Hexagon::W9,  Hexagon::W10, Hexagon::W11,
527       Hexagon::W12, Hexagon::W13, Hexagon::W14, Hexagon::W15};
528 
529   return (DecodeRegisterClass(Inst, RegNo >> 1, VecDblRegDecoderTable));
530 }
531 
532 static DecodeStatus DecodePredRegsRegisterClass(MCInst &Inst, unsigned RegNo,
533                                                 uint64_t /*Address*/,
534                                                 const void *Decoder) {
535   static const MCPhysReg PredRegDecoderTable[] = {Hexagon::P0, Hexagon::P1,
536                                                   Hexagon::P2, Hexagon::P3};
537 
538   return DecodeRegisterClass(Inst, RegNo, PredRegDecoderTable);
539 }
540 
541 static DecodeStatus DecodeVecPredRegsRegisterClass(MCInst &Inst, unsigned RegNo,
542                                                    uint64_t /*Address*/,
543                                                    const void *Decoder) {
544   static const MCPhysReg VecPredRegDecoderTable[] = {Hexagon::Q0, Hexagon::Q1,
545                                                      Hexagon::Q2, Hexagon::Q3};
546 
547   return DecodeRegisterClass(Inst, RegNo, VecPredRegDecoderTable);
548 }
549 
550 static DecodeStatus DecodeCtrRegsRegisterClass(MCInst &Inst, unsigned RegNo,
551                                                uint64_t /*Address*/,
552                                                const void *Decoder) {
553   using namespace Hexagon;
554   static const MCPhysReg CtrlRegDecoderTable[] = {
555     /*  0 */  SA0,        LC0,        SA1,        LC1,
556     /*  4 */  P3_0,       C5,         M0,         M1,
557     /*  8 */  USR,        PC,         UGP,        GP,
558     /* 12 */  CS0,        CS1,        UPCYCLELO,  UPCYCLEHI,
559     /* 16 */  FRAMELIMIT, FRAMEKEY,   PKTCOUNTLO, PKTCOUNTHI,
560     /* 20 */  0,          0,          0,          0,
561     /* 24 */  0,          0,          0,          0,
562     /* 28 */  0,          0,          UTIMERLO,   UTIMERHI
563   };
564 
565   if (RegNo >= array_lengthof(CtrlRegDecoderTable))
566     return MCDisassembler::Fail;
567 
568   static_assert(NoRegister == 0, "Expecting NoRegister to be 0");
569   if (CtrlRegDecoderTable[RegNo] == NoRegister)
570     return MCDisassembler::Fail;
571 
572   unsigned Register = CtrlRegDecoderTable[RegNo];
573   Inst.addOperand(MCOperand::createReg(Register));
574   return MCDisassembler::Success;
575 }
576 
577 static DecodeStatus DecodeCtrRegs64RegisterClass(MCInst &Inst, unsigned RegNo,
578                                                  uint64_t /*Address*/,
579                                                  const void *Decoder) {
580   using namespace Hexagon;
581   static const MCPhysReg CtrlReg64DecoderTable[] = {
582     /*  0 */  C1_0,       0,          C3_2,       0,
583     /*  4 */  C5_4,       0,          C7_6,       0,
584     /*  8 */  C9_8,       0,          C11_10,     0,
585     /* 12 */  CS,         0,          UPCYCLE,    0,
586     /* 16 */  C17_16,     0,          PKTCOUNT,   0,
587     /* 20 */  0,          0,          0,          0,
588     /* 24 */  0,          0,          0,          0,
589     /* 28 */  0,          0,          UTIMER,     0
590   };
591 
592   if (RegNo >= array_lengthof(CtrlReg64DecoderTable))
593     return MCDisassembler::Fail;
594 
595   static_assert(NoRegister == 0, "Expecting NoRegister to be 0");
596   if (CtrlReg64DecoderTable[RegNo] == NoRegister)
597     return MCDisassembler::Fail;
598 
599   unsigned Register = CtrlReg64DecoderTable[RegNo];
600   Inst.addOperand(MCOperand::createReg(Register));
601   return MCDisassembler::Success;
602 }
603 
604 static DecodeStatus DecodeModRegsRegisterClass(MCInst &Inst, unsigned RegNo,
605                                                uint64_t /*Address*/,
606                                                const void *Decoder) {
607   unsigned Register = 0;
608   switch (RegNo) {
609   case 0:
610     Register = Hexagon::M0;
611     break;
612   case 1:
613     Register = Hexagon::M1;
614     break;
615   default:
616     return MCDisassembler::Fail;
617   }
618   Inst.addOperand(MCOperand::createReg(Register));
619   return MCDisassembler::Success;
620 }
621 
622 static DecodeStatus unsignedImmDecoder(MCInst &MI, unsigned tmp,
623                                        uint64_t /*Address*/,
624                                        const void *Decoder) {
625   HexagonDisassembler const &Disassembler = disassembler(Decoder);
626   int64_t FullValue =
627       fullValue(*Disassembler.MCII, **Disassembler.CurrentBundle, MI, tmp);
628   assert(FullValue >= 0 && "Negative in unsigned decoder");
629   HexagonMCInstrInfo::addConstant(MI, FullValue, Disassembler.getContext());
630   return MCDisassembler::Success;
631 }
632 
633 static DecodeStatus s32_0ImmDecoder(MCInst &MI, unsigned tmp,
634                                     uint64_t /*Address*/, const void *Decoder) {
635   HexagonDisassembler const &Disassembler = disassembler(Decoder);
636   unsigned Bits = HexagonMCInstrInfo::getExtentBits(*Disassembler.MCII, MI);
637   tmp = SignExtend64(tmp, Bits);
638   signedDecoder<32>(MI, tmp, Decoder);
639   return MCDisassembler::Success;
640 }
641 
642 // custom decoder for various jump/call immediates
643 static DecodeStatus brtargetDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
644                                     const void *Decoder) {
645   HexagonDisassembler const &Disassembler = disassembler(Decoder);
646   unsigned Bits = HexagonMCInstrInfo::getExtentBits(*Disassembler.MCII, MI);
647   // r13_2 is not extendable, so if there are no extent bits, it's r13_2
648   if (Bits == 0)
649     Bits = 15;
650   uint32_t FullValue =
651       fullValue(*Disassembler.MCII, **Disassembler.CurrentBundle, MI,
652                 SignExtend64(tmp, Bits));
653   int64_t Extended = SignExtend64<32>(FullValue) + Address;
654   if (!Disassembler.tryAddingSymbolicOperand(MI, Extended, Address, true, 0, 4))
655     HexagonMCInstrInfo::addConstant(MI, Extended, Disassembler.getContext());
656   return MCDisassembler::Success;
657 }
658 
659 
660