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/Endian.h"
28 #include "llvm/Support/MathExtras.h"
29 #include "llvm/Support/TargetRegistry.h"
30 #include "llvm/Support/raw_ostream.h"
31 #include <cassert>
32 #include <cstddef>
33 #include <cstdint>
34 #include <memory>
35 
36 using namespace llvm;
37 using namespace Hexagon;
38 
39 using DecodeStatus = MCDisassembler::DecodeStatus;
40 
41 namespace {
42 
43 /// \brief Hexagon disassembler for all Hexagon platforms.
44 class HexagonDisassembler : public MCDisassembler {
45 public:
46   std::unique_ptr<MCInstrInfo const> const MCII;
47   std::unique_ptr<MCInst *> CurrentBundle;
48 
49   HexagonDisassembler(const MCSubtargetInfo &STI, MCContext &Ctx,
50                       MCInstrInfo const *MCII)
51       : MCDisassembler(STI, Ctx), MCII(MCII), CurrentBundle(new MCInst *) {}
52 
53   DecodeStatus getSingleInstruction(MCInst &Instr, MCInst &MCB,
54                                     ArrayRef<uint8_t> Bytes, uint64_t Address,
55                                     raw_ostream &VStream, raw_ostream &CStream,
56                                     bool &Complete) const;
57   DecodeStatus getInstruction(MCInst &Instr, uint64_t &Size,
58                               ArrayRef<uint8_t> Bytes, uint64_t Address,
59                               raw_ostream &VStream,
60                               raw_ostream &CStream) const override;
61   void addSubinstOperands(MCInst *MI, unsigned opcode, unsigned inst) const;
62 };
63 
64 } // end anonymous namespace
65 
66 static uint32_t fullValue(MCInstrInfo const &MCII, MCInst &MCB, MCInst &MI,
67                           int64_t Value) {
68   MCInst const *Extender = HexagonMCInstrInfo::extenderForIndex(
69     MCB, HexagonMCInstrInfo::bundleSize(MCB));
70   if (!Extender || MI.size() != HexagonMCInstrInfo::getExtendableOp(MCII, MI))
71     return Value;
72   unsigned Alignment = HexagonMCInstrInfo::getExtentAlignment(MCII, MI);
73   uint32_t Lower6 = static_cast<uint32_t>(Value >> Alignment) & 0x3f;
74   int64_t Bits;
75   bool Success = Extender->getOperand(0).getExpr()->evaluateAsAbsolute(Bits);
76   assert(Success); (void)Success;
77   uint32_t Upper26 = static_cast<uint32_t>(Bits);
78   uint32_t Operand = Upper26 | Lower6;
79   return Operand;
80 }
81 
82 static HexagonDisassembler const &disassembler(void const *Decoder) {
83   return *static_cast<HexagonDisassembler const *>(Decoder);
84 }
85 
86 template <size_t T>
87 static void signedDecoder(MCInst &MI, unsigned tmp, const void *Decoder) {
88   HexagonDisassembler const &Disassembler = disassembler(Decoder);
89   int64_t FullValue =
90       fullValue(*Disassembler.MCII, **Disassembler.CurrentBundle, MI,
91                 SignExtend64<T>(tmp));
92   int64_t Extended = SignExtend64<32>(FullValue);
93   HexagonMCInstrInfo::addConstant(MI, Extended, Disassembler.getContext());
94 }
95 
96 // Forward declare these because the auto-generated code will reference them.
97 // Definitions are further down.
98 
99 static DecodeStatus DecodeIntRegsRegisterClass(MCInst &Inst, unsigned RegNo,
100                                                uint64_t Address,
101                                                const void *Decoder);
102 static DecodeStatus DecodeGeneralSubRegsRegisterClass(MCInst &Inst,
103                                                       unsigned RegNo,
104                                                       uint64_t Address,
105                                                       const void *Decoder);
106 static DecodeStatus DecodeIntRegsLow8RegisterClass(MCInst &Inst, unsigned RegNo,
107                                                    uint64_t Address,
108                                                    const void *Decoder);
109 static DecodeStatus DecodeHvxVRRegisterClass(MCInst &Inst, unsigned RegNo,
110                                                   uint64_t Address,
111                                                   const void *Decoder);
112 static DecodeStatus DecodeDoubleRegsRegisterClass(MCInst &Inst, unsigned RegNo,
113                                                   uint64_t Address,
114                                                   const void *Decoder);
115 static DecodeStatus
116 DecodeGeneralDoubleLow8RegsRegisterClass(MCInst &Inst, unsigned RegNo,
117                                          uint64_t Address, const void *Decoder);
118 static DecodeStatus DecodeHvxWRRegisterClass(MCInst &Inst, unsigned RegNo,
119                                                   uint64_t Address,
120                                                   const void *Decoder);
121 static DecodeStatus DecodePredRegsRegisterClass(MCInst &Inst, unsigned RegNo,
122                                                 uint64_t Address,
123                                                 const void *Decoder);
124 static DecodeStatus DecodeHvxQRRegisterClass(MCInst &Inst, unsigned RegNo,
125                                                    uint64_t Address,
126                                                    const void *Decoder);
127 static DecodeStatus DecodeCtrRegsRegisterClass(MCInst &Inst, unsigned RegNo,
128                                                uint64_t Address,
129                                                const void *Decoder);
130 static DecodeStatus DecodeModRegsRegisterClass(MCInst &Inst, unsigned RegNo,
131                                                uint64_t Address,
132                                                const void *Decoder);
133 static DecodeStatus DecodeCtrRegs64RegisterClass(MCInst &Inst, unsigned RegNo,
134                                                  uint64_t Address,
135                                                  const void *Decoder);
136 
137 static DecodeStatus unsignedImmDecoder(MCInst &MI, unsigned tmp,
138                                        uint64_t Address, const void *Decoder);
139 static DecodeStatus s32_0ImmDecoder(MCInst &MI, unsigned tmp,
140                                     uint64_t /*Address*/, const void *Decoder);
141 static DecodeStatus s8_0ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
142                                  const void *Decoder);
143 static DecodeStatus s6_0ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
144                                    const void *Decoder);
145 static DecodeStatus s4_0ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
146                                    const void *Decoder);
147 static DecodeStatus s4_1ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
148                                    const void *Decoder);
149 static DecodeStatus s4_2ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
150                                    const void *Decoder);
151 static DecodeStatus s4_3ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
152                                    const void *Decoder);
153 static DecodeStatus s3_0ImmDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
154                                    const void *Decoder);
155 static DecodeStatus brtargetDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
156                                     const void *Decoder);
157 
158 #include "HexagonDepDecoders.h"
159 #include "HexagonGenDisassemblerTables.inc"
160 
161 static MCDisassembler *createHexagonDisassembler(const Target &T,
162                                                  const MCSubtargetInfo &STI,
163                                                  MCContext &Ctx) {
164   return new HexagonDisassembler(STI, Ctx, T.createMCInstrInfo());
165 }
166 
167 extern "C" void LLVMInitializeHexagonDisassembler() {
168   TargetRegistry::RegisterMCDisassembler(getTheHexagonTarget(),
169                                          createHexagonDisassembler);
170 }
171 
172 DecodeStatus HexagonDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
173                                                  ArrayRef<uint8_t> Bytes,
174                                                  uint64_t Address,
175                                                  raw_ostream &os,
176                                                  raw_ostream &cs) const {
177   DecodeStatus Result = DecodeStatus::Success;
178   bool Complete = false;
179   Size = 0;
180 
181   *CurrentBundle = &MI;
182   MI = HexagonMCInstrInfo::createBundle();
183   while (Result == Success && !Complete) {
184     if (Bytes.size() < HEXAGON_INSTR_SIZE)
185       return MCDisassembler::Fail;
186     MCInst *Inst = new (getContext()) MCInst;
187     Result = getSingleInstruction(*Inst, MI, Bytes, Address, os, cs, Complete);
188     MI.addOperand(MCOperand::createInst(Inst));
189     Size += HEXAGON_INSTR_SIZE;
190     Bytes = Bytes.slice(HEXAGON_INSTR_SIZE);
191   }
192   if (Result == MCDisassembler::Fail)
193     return Result;
194   if (Size > HEXAGON_MAX_PACKET_SIZE)
195     return MCDisassembler::Fail;
196   HexagonMCChecker Checker(getContext(), *MCII, STI, MI,
197                            *getContext().getRegisterInfo(), false);
198   if (!Checker.check())
199     return MCDisassembler::Fail;
200   return MCDisassembler::Success;
201 }
202 
203 static void adjustDuplex(MCInst &MI, MCContext &Context) {
204   switch (MI.getOpcode()) {
205   case Hexagon::SA1_setin1:
206     MI.insert(MI.begin() + 1,
207               MCOperand::createExpr(MCConstantExpr::create(-1, Context)));
208     break;
209   case Hexagon::SA1_dec:
210     MI.insert(MI.begin() + 2,
211               MCOperand::createExpr(MCConstantExpr::create(-1, Context)));
212     break;
213   default:
214     break;
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 DecodeHvxVRRegisterClass(MCInst &Inst, unsigned RegNo,
485                                              uint64_t /*Address*/,
486                                              const void *Decoder) {
487   static const MCPhysReg HvxVRDecoderTable[] = {
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, HvxVRDecoderTable);
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 DecodeHvxWRRegisterClass(MCInst &Inst, unsigned RegNo,
521                                              uint64_t /*Address*/,
522                                              const void *Decoder) {
523   static const MCPhysReg HvxWRDecoderTable[] = {
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, HvxWRDecoderTable));
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 DecodeHvxQRRegisterClass(MCInst &Inst, unsigned RegNo,
542                                              uint64_t /*Address*/,
543                                              const void *Decoder) {
544   static const MCPhysReg HvxQRDecoderTable[] = {Hexagon::Q0, Hexagon::Q1,
545                                                 Hexagon::Q2, Hexagon::Q3};
546 
547   return DecodeRegisterClass(Inst, RegNo, HvxQRDecoderTable);
548 }
549 
550 static DecodeStatus DecodeCtrRegsRegisterClass(MCInst &Inst, unsigned RegNo,
551                                                uint64_t /*Address*/,
552                                                const void *Decoder) {
553   using namespace Hexagon;
554 
555   static const MCPhysReg CtrlRegDecoderTable[] = {
556     /*  0 */  SA0,        LC0,        SA1,        LC1,
557     /*  4 */  P3_0,       C5,         M0,         M1,
558     /*  8 */  USR,        PC,         UGP,        GP,
559     /* 12 */  CS0,        CS1,        UPCYCLELO,  UPCYCLEHI,
560     /* 16 */  FRAMELIMIT, FRAMEKEY,   PKTCOUNTLO, PKTCOUNTHI,
561     /* 20 */  0,          0,          0,          0,
562     /* 24 */  0,          0,          0,          0,
563     /* 28 */  0,          0,          UTIMERLO,   UTIMERHI
564   };
565 
566   if (RegNo >= array_lengthof(CtrlRegDecoderTable))
567     return MCDisassembler::Fail;
568 
569   static_assert(NoRegister == 0, "Expecting NoRegister to be 0");
570   if (CtrlRegDecoderTable[RegNo] == NoRegister)
571     return MCDisassembler::Fail;
572 
573   unsigned Register = CtrlRegDecoderTable[RegNo];
574   Inst.addOperand(MCOperand::createReg(Register));
575   return MCDisassembler::Success;
576 }
577 
578 static DecodeStatus DecodeCtrRegs64RegisterClass(MCInst &Inst, unsigned RegNo,
579                                                  uint64_t /*Address*/,
580                                                  const void *Decoder) {
581   using namespace Hexagon;
582 
583   static const MCPhysReg CtrlReg64DecoderTable[] = {
584     /*  0 */  C1_0,       0,          C3_2,       0,
585     /*  4 */  C5_4,       0,          C7_6,       0,
586     /*  8 */  C9_8,       0,          C11_10,     0,
587     /* 12 */  CS,         0,          UPCYCLE,    0,
588     /* 16 */  C17_16,     0,          PKTCOUNT,   0,
589     /* 20 */  0,          0,          0,          0,
590     /* 24 */  0,          0,          0,          0,
591     /* 28 */  0,          0,          UTIMER,     0
592   };
593 
594   if (RegNo >= array_lengthof(CtrlReg64DecoderTable))
595     return MCDisassembler::Fail;
596 
597   static_assert(NoRegister == 0, "Expecting NoRegister to be 0");
598   if (CtrlReg64DecoderTable[RegNo] == NoRegister)
599     return MCDisassembler::Fail;
600 
601   unsigned Register = CtrlReg64DecoderTable[RegNo];
602   Inst.addOperand(MCOperand::createReg(Register));
603   return MCDisassembler::Success;
604 }
605 
606 static DecodeStatus DecodeModRegsRegisterClass(MCInst &Inst, unsigned RegNo,
607                                                uint64_t /*Address*/,
608                                                const void *Decoder) {
609   unsigned Register = 0;
610   switch (RegNo) {
611   case 0:
612     Register = Hexagon::M0;
613     break;
614   case 1:
615     Register = Hexagon::M1;
616     break;
617   default:
618     return MCDisassembler::Fail;
619   }
620   Inst.addOperand(MCOperand::createReg(Register));
621   return MCDisassembler::Success;
622 }
623 
624 static DecodeStatus unsignedImmDecoder(MCInst &MI, unsigned tmp,
625                                        uint64_t /*Address*/,
626                                        const void *Decoder) {
627   HexagonDisassembler const &Disassembler = disassembler(Decoder);
628   int64_t FullValue =
629       fullValue(*Disassembler.MCII, **Disassembler.CurrentBundle, MI, tmp);
630   assert(FullValue >= 0 && "Negative in unsigned decoder");
631   HexagonMCInstrInfo::addConstant(MI, FullValue, Disassembler.getContext());
632   return MCDisassembler::Success;
633 }
634 
635 static DecodeStatus s32_0ImmDecoder(MCInst &MI, unsigned tmp,
636                                     uint64_t /*Address*/, const void *Decoder) {
637   HexagonDisassembler const &Disassembler = disassembler(Decoder);
638   unsigned Bits = HexagonMCInstrInfo::getExtentBits(*Disassembler.MCII, MI);
639   tmp = SignExtend64(tmp, Bits);
640   signedDecoder<32>(MI, tmp, Decoder);
641   return MCDisassembler::Success;
642 }
643 
644 // custom decoder for various jump/call immediates
645 static DecodeStatus brtargetDecoder(MCInst &MI, unsigned tmp, uint64_t Address,
646                                     const void *Decoder) {
647   HexagonDisassembler const &Disassembler = disassembler(Decoder);
648   unsigned Bits = HexagonMCInstrInfo::getExtentBits(*Disassembler.MCII, MI);
649   // r13_2 is not extendable, so if there are no extent bits, it's r13_2
650   if (Bits == 0)
651     Bits = 15;
652   uint32_t FullValue =
653       fullValue(*Disassembler.MCII, **Disassembler.CurrentBundle, MI,
654                 SignExtend64(tmp, Bits));
655   int64_t Extended = SignExtend64<32>(FullValue) + Address;
656   if (!Disassembler.tryAddingSymbolicOperand(MI, Extended, Address, true, 0, 4))
657     HexagonMCInstrInfo::addConstant(MI, Extended, Disassembler.getContext());
658   return MCDisassembler::Success;
659 }
660