xref: /llvm-project/llvm/lib/Target/ARM/Disassembler/ARMDisassembler.cpp (revision f01e2de5e627b242233dfc8121d340395fa74ec7)
1 //===- ARMDisassembler.cpp - Disassembler for ARM/Thumb ISA -----*- 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 #define DEBUG_TYPE "arm-disassembler"
11 
12 #include "ARM.h"
13 #include "ARMRegisterInfo.h"
14 #include "ARMSubtarget.h"
15 #include "MCTargetDesc/ARMAddressingModes.h"
16 #include "MCTargetDesc/ARMBaseInfo.h"
17 #include "llvm/MC/EDInstInfo.h"
18 #include "llvm/MC/MCInst.h"
19 #include "llvm/MC/MCExpr.h"
20 #include "llvm/MC/MCContext.h"
21 #include "llvm/MC/MCDisassembler.h"
22 #include "llvm/Support/Debug.h"
23 #include "llvm/Support/MemoryObject.h"
24 #include "llvm/Support/ErrorHandling.h"
25 #include "llvm/Support/TargetRegistry.h"
26 #include "llvm/Support/raw_ostream.h"
27 
28 using namespace llvm;
29 
30 typedef MCDisassembler::DecodeStatus DecodeStatus;
31 
32 namespace {
33 /// ARMDisassembler - ARM disassembler for all ARM platforms.
34 class ARMDisassembler : public MCDisassembler {
35 public:
36   /// Constructor     - Initializes the disassembler.
37   ///
38   ARMDisassembler(const MCSubtargetInfo &STI) :
39     MCDisassembler(STI) {
40   }
41 
42   ~ARMDisassembler() {
43   }
44 
45   /// getInstruction - See MCDisassembler.
46   DecodeStatus getInstruction(MCInst &instr,
47                               uint64_t &size,
48                               const MemoryObject &region,
49                               uint64_t address,
50                               raw_ostream &vStream,
51                               raw_ostream &cStream) const;
52 
53   /// getEDInfo - See MCDisassembler.
54   EDInstInfo *getEDInfo() const;
55 private:
56 };
57 
58 /// ThumbDisassembler - Thumb disassembler for all Thumb platforms.
59 class ThumbDisassembler : public MCDisassembler {
60 public:
61   /// Constructor     - Initializes the disassembler.
62   ///
63   ThumbDisassembler(const MCSubtargetInfo &STI) :
64     MCDisassembler(STI) {
65   }
66 
67   ~ThumbDisassembler() {
68   }
69 
70   /// getInstruction - See MCDisassembler.
71   DecodeStatus getInstruction(MCInst &instr,
72                               uint64_t &size,
73                               const MemoryObject &region,
74                               uint64_t address,
75                               raw_ostream &vStream,
76                               raw_ostream &cStream) const;
77 
78   /// getEDInfo - See MCDisassembler.
79   EDInstInfo *getEDInfo() const;
80 private:
81   mutable std::vector<unsigned> ITBlock;
82   DecodeStatus AddThumbPredicate(MCInst&) const;
83   void UpdateThumbVFPPredicate(MCInst&) const;
84 };
85 }
86 
87 static bool Check(DecodeStatus &Out, DecodeStatus In) {
88   switch (In) {
89     case MCDisassembler::Success:
90       // Out stays the same.
91       return true;
92     case MCDisassembler::SoftFail:
93       Out = In;
94       return true;
95     case MCDisassembler::Fail:
96       Out = In;
97       return false;
98   }
99   return false;
100 }
101 
102 
103 // Forward declare these because the autogenerated code will reference them.
104 // Definitions are further down.
105 static DecodeStatus DecodeGPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
106                                    uint64_t Address, const void *Decoder);
107 static DecodeStatus DecodeGPRnopcRegisterClass(llvm::MCInst &Inst,
108                                                unsigned RegNo, uint64_t Address,
109                                                const void *Decoder);
110 static DecodeStatus DecodetGPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
111                                    uint64_t Address, const void *Decoder);
112 static DecodeStatus DecodetcGPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
113                                    uint64_t Address, const void *Decoder);
114 static DecodeStatus DecoderGPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
115                                    uint64_t Address, const void *Decoder);
116 static DecodeStatus DecodeSPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
117                                    uint64_t Address, const void *Decoder);
118 static DecodeStatus DecodeDPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
119                                    uint64_t Address, const void *Decoder);
120 static DecodeStatus DecodeDPR_8RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
121                                    uint64_t Address, const void *Decoder);
122 static DecodeStatus DecodeDPR_VFP2RegisterClass(llvm::MCInst &Inst,
123                                                 unsigned RegNo,
124                                                 uint64_t Address,
125                                                 const void *Decoder);
126 static DecodeStatus DecodeQPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
127                                    uint64_t Address, const void *Decoder);
128 
129 static DecodeStatus DecodePredicateOperand(llvm::MCInst &Inst, unsigned Val,
130                                uint64_t Address, const void *Decoder);
131 static DecodeStatus DecodeCCOutOperand(llvm::MCInst &Inst, unsigned Val,
132                                uint64_t Address, const void *Decoder);
133 static DecodeStatus DecodeSOImmOperand(llvm::MCInst &Inst, unsigned Val,
134                                uint64_t Address, const void *Decoder);
135 static DecodeStatus DecodeRegListOperand(llvm::MCInst &Inst, unsigned Val,
136                                uint64_t Address, const void *Decoder);
137 static DecodeStatus DecodeSPRRegListOperand(llvm::MCInst &Inst, unsigned Val,
138                                uint64_t Address, const void *Decoder);
139 static DecodeStatus DecodeDPRRegListOperand(llvm::MCInst &Inst, unsigned Val,
140                                uint64_t Address, const void *Decoder);
141 
142 static DecodeStatus DecodeBitfieldMaskOperand(llvm::MCInst &Inst, unsigned Insn,
143                                uint64_t Address, const void *Decoder);
144 static DecodeStatus DecodeCopMemInstruction(llvm::MCInst &Inst, unsigned Insn,
145                                uint64_t Address, const void *Decoder);
146 static DecodeStatus DecodeAddrMode2IdxInstruction(llvm::MCInst &Inst,
147                                                   unsigned Insn,
148                                                   uint64_t Address,
149                                                   const void *Decoder);
150 static DecodeStatus DecodeSORegMemOperand(llvm::MCInst &Inst, unsigned Insn,
151                                uint64_t Address, const void *Decoder);
152 static DecodeStatus DecodeAddrMode3Instruction(llvm::MCInst &Inst,unsigned Insn,
153                                uint64_t Address, const void *Decoder);
154 static DecodeStatus DecodeSORegImmOperand(llvm::MCInst &Inst, unsigned Insn,
155                                uint64_t Address, const void *Decoder);
156 static DecodeStatus DecodeSORegRegOperand(llvm::MCInst &Inst, unsigned Insn,
157                                uint64_t Address, const void *Decoder);
158 
159 static DecodeStatus DecodeMemMultipleWritebackInstruction(llvm::MCInst & Inst,
160                                                   unsigned Insn,
161                                                   uint64_t Adddress,
162                                                   const void *Decoder);
163 static DecodeStatus DecodeSMLAInstruction(llvm::MCInst &Inst, unsigned Insn,
164                                uint64_t Address, const void *Decoder);
165 static DecodeStatus DecodeCPSInstruction(llvm::MCInst &Inst, unsigned Insn,
166                                uint64_t Address, const void *Decoder);
167 static DecodeStatus DecodeT2CPSInstruction(llvm::MCInst &Inst, unsigned Insn,
168                                uint64_t Address, const void *Decoder);
169 static DecodeStatus DecodeAddrModeImm12Operand(llvm::MCInst &Inst, unsigned Val,
170                                uint64_t Address, const void *Decoder);
171 static DecodeStatus DecodeAddrMode5Operand(llvm::MCInst &Inst, unsigned Val,
172                                uint64_t Address, const void *Decoder);
173 static DecodeStatus DecodeAddrMode7Operand(llvm::MCInst &Inst, unsigned Val,
174                                uint64_t Address, const void *Decoder);
175 static DecodeStatus DecodeBranchImmInstruction(llvm::MCInst &Inst,unsigned Insn,
176                                uint64_t Address, const void *Decoder);
177 static DecodeStatus DecodeVCVTImmOperand(llvm::MCInst &Inst, unsigned Val,
178                                uint64_t Address, const void *Decoder);
179 static DecodeStatus DecodeAddrMode6Operand(llvm::MCInst &Inst, unsigned Val,
180                                uint64_t Address, const void *Decoder);
181 static DecodeStatus DecodeVLDInstruction(llvm::MCInst &Inst, unsigned Val,
182                                uint64_t Address, const void *Decoder);
183 static DecodeStatus DecodeVSTInstruction(llvm::MCInst &Inst, unsigned Val,
184                                uint64_t Address, const void *Decoder);
185 static DecodeStatus DecodeVLD1DupInstruction(llvm::MCInst &Inst, unsigned Val,
186                                uint64_t Address, const void *Decoder);
187 static DecodeStatus DecodeVLD2DupInstruction(llvm::MCInst &Inst, unsigned Val,
188                                uint64_t Address, const void *Decoder);
189 static DecodeStatus DecodeVLD3DupInstruction(llvm::MCInst &Inst, unsigned Val,
190                                uint64_t Address, const void *Decoder);
191 static DecodeStatus DecodeVLD4DupInstruction(llvm::MCInst &Inst, unsigned Val,
192                                uint64_t Address, const void *Decoder);
193 static DecodeStatus DecodeNEONModImmInstruction(llvm::MCInst &Inst,unsigned Val,
194                                uint64_t Address, const void *Decoder);
195 static DecodeStatus DecodeVSHLMaxInstruction(llvm::MCInst &Inst, unsigned Val,
196                                uint64_t Address, const void *Decoder);
197 static DecodeStatus DecodeShiftRight8Imm(llvm::MCInst &Inst, unsigned Val,
198                                uint64_t Address, const void *Decoder);
199 static DecodeStatus DecodeShiftRight16Imm(llvm::MCInst &Inst, unsigned Val,
200                                uint64_t Address, const void *Decoder);
201 static DecodeStatus DecodeShiftRight32Imm(llvm::MCInst &Inst, unsigned Val,
202                                uint64_t Address, const void *Decoder);
203 static DecodeStatus DecodeShiftRight64Imm(llvm::MCInst &Inst, unsigned Val,
204                                uint64_t Address, const void *Decoder);
205 static DecodeStatus DecodeTBLInstruction(llvm::MCInst &Inst, unsigned Insn,
206                                uint64_t Address, const void *Decoder);
207 static DecodeStatus DecodeVFPfpImm(llvm::MCInst &Inst, unsigned Val,
208                                uint64_t Address, const void *Decoder);
209 static DecodeStatus DecodePostIdxReg(llvm::MCInst &Inst, unsigned Insn,
210                                uint64_t Address, const void *Decoder);
211 static DecodeStatus DecodeCoprocessor(llvm::MCInst &Inst, unsigned Insn,
212                                uint64_t Address, const void *Decoder);
213 static DecodeStatus DecodeMemBarrierOption(llvm::MCInst &Inst, unsigned Insn,
214                                uint64_t Address, const void *Decoder);
215 static DecodeStatus DecodeMSRMask(llvm::MCInst &Inst, unsigned Insn,
216                                uint64_t Address, const void *Decoder);
217 static DecodeStatus DecodeDoubleRegLoad(llvm::MCInst &Inst, unsigned Insn,
218                                uint64_t Address, const void *Decoder);
219 static DecodeStatus DecodeDoubleRegStore(llvm::MCInst &Inst, unsigned Insn,
220                                uint64_t Address, const void *Decoder);
221 static DecodeStatus DecodeLDRPreImm(llvm::MCInst &Inst, unsigned Insn,
222                                uint64_t Address, const void *Decoder);
223 static DecodeStatus DecodeLDRPreReg(llvm::MCInst &Inst, unsigned Insn,
224                                uint64_t Address, const void *Decoder);
225 static DecodeStatus DecodeSTRPreImm(llvm::MCInst &Inst, unsigned Insn,
226                                uint64_t Address, const void *Decoder);
227 static DecodeStatus DecodeSTRPreReg(llvm::MCInst &Inst, unsigned Insn,
228                                uint64_t Address, const void *Decoder);
229 static DecodeStatus DecodeVLD1LN(llvm::MCInst &Inst, unsigned Insn,
230                                uint64_t Address, const void *Decoder);
231 static DecodeStatus DecodeVLD2LN(llvm::MCInst &Inst, unsigned Insn,
232                                uint64_t Address, const void *Decoder);
233 static DecodeStatus DecodeVLD3LN(llvm::MCInst &Inst, unsigned Insn,
234                                uint64_t Address, const void *Decoder);
235 static DecodeStatus DecodeVLD4LN(llvm::MCInst &Inst, unsigned Insn,
236                                uint64_t Address, const void *Decoder);
237 static DecodeStatus DecodeVST1LN(llvm::MCInst &Inst, unsigned Insn,
238                                uint64_t Address, const void *Decoder);
239 static DecodeStatus DecodeVST2LN(llvm::MCInst &Inst, unsigned Insn,
240                                uint64_t Address, const void *Decoder);
241 static DecodeStatus DecodeVST3LN(llvm::MCInst &Inst, unsigned Insn,
242                                uint64_t Address, const void *Decoder);
243 static DecodeStatus DecodeVST4LN(llvm::MCInst &Inst, unsigned Insn,
244                                uint64_t Address, const void *Decoder);
245 static DecodeStatus DecodeVMOVSRR(llvm::MCInst &Inst, unsigned Insn,
246                                uint64_t Address, const void *Decoder);
247 static DecodeStatus DecodeVMOVRRS(llvm::MCInst &Inst, unsigned Insn,
248                                uint64_t Address, const void *Decoder);
249 
250 static DecodeStatus DecodeThumbAddSpecialReg(llvm::MCInst &Inst, uint16_t Insn,
251                                uint64_t Address, const void *Decoder);
252 static DecodeStatus DecodeThumbBROperand(llvm::MCInst &Inst, unsigned Val,
253                                uint64_t Address, const void *Decoder);
254 static DecodeStatus DecodeT2BROperand(llvm::MCInst &Inst, unsigned Val,
255                                uint64_t Address, const void *Decoder);
256 static DecodeStatus DecodeThumbCmpBROperand(llvm::MCInst &Inst, unsigned Val,
257                                uint64_t Address, const void *Decoder);
258 static DecodeStatus DecodeThumbAddrModeRR(llvm::MCInst &Inst, unsigned Val,
259                                uint64_t Address, const void *Decoder);
260 static DecodeStatus DecodeThumbAddrModeIS(llvm::MCInst &Inst, unsigned Val,
261                                uint64_t Address, const void *Decoder);
262 static DecodeStatus DecodeThumbAddrModePC(llvm::MCInst &Inst, unsigned Val,
263                                uint64_t Address, const void *Decoder);
264 static DecodeStatus DecodeThumbAddrModeSP(llvm::MCInst &Inst, unsigned Val,
265                                uint64_t Address, const void *Decoder);
266 static DecodeStatus DecodeT2AddrModeSOReg(llvm::MCInst &Inst, unsigned Val,
267                                uint64_t Address, const void *Decoder);
268 static DecodeStatus DecodeT2LoadShift(llvm::MCInst &Inst, unsigned Val,
269                                uint64_t Address, const void *Decoder);
270 static DecodeStatus DecodeT2Imm8S4(llvm::MCInst &Inst, unsigned Val,
271                                uint64_t Address, const void *Decoder);
272 static DecodeStatus DecodeT2AddrModeImm8s4(llvm::MCInst &Inst, unsigned Val,
273                                uint64_t Address, const void *Decoder);
274 static DecodeStatus DecodeT2AddrModeImm0_1020s4(llvm::MCInst &Inst,unsigned Val,
275                                uint64_t Address, const void *Decoder);
276 static DecodeStatus DecodeT2Imm8(llvm::MCInst &Inst, unsigned Val,
277                                uint64_t Address, const void *Decoder);
278 static DecodeStatus DecodeT2AddrModeImm8(llvm::MCInst &Inst, unsigned Val,
279                                uint64_t Address, const void *Decoder);
280 static DecodeStatus DecodeThumbAddSPImm(llvm::MCInst &Inst, uint16_t Val,
281                                uint64_t Address, const void *Decoder);
282 static DecodeStatus DecodeThumbAddSPReg(llvm::MCInst &Inst, uint16_t Insn,
283                                 uint64_t Address, const void *Decoder);
284 static DecodeStatus DecodeThumbCPS(llvm::MCInst &Inst, uint16_t Insn,
285                                 uint64_t Address, const void *Decoder);
286 static DecodeStatus DecodeThumbBLXOffset(llvm::MCInst &Inst, unsigned Insn,
287                                 uint64_t Address, const void *Decoder);
288 static DecodeStatus DecodeT2AddrModeImm12(llvm::MCInst &Inst, unsigned Val,
289                                 uint64_t Address, const void *Decoder);
290 static DecodeStatus DecodeThumbTableBranch(llvm::MCInst &Inst, unsigned Val,
291                                 uint64_t Address, const void *Decoder);
292 static DecodeStatus DecodeThumb2BCCInstruction(llvm::MCInst &Inst, unsigned Val,
293                                 uint64_t Address, const void *Decoder);
294 static DecodeStatus DecodeT2SOImm(llvm::MCInst &Inst, unsigned Val,
295                                 uint64_t Address, const void *Decoder);
296 static DecodeStatus DecodeThumbBCCTargetOperand(llvm::MCInst &Inst,unsigned Val,
297                                 uint64_t Address, const void *Decoder);
298 static DecodeStatus DecodeThumbBLTargetOperand(llvm::MCInst &Inst, unsigned Val,
299                                 uint64_t Address, const void *Decoder);
300 static DecodeStatus DecodeIT(llvm::MCInst &Inst, unsigned Val,
301                                 uint64_t Address, const void *Decoder);
302 static DecodeStatus DecodeT2LDRDPreInstruction(llvm::MCInst &Inst,unsigned Insn,
303                                uint64_t Address, const void *Decoder);
304 static DecodeStatus DecodeT2STRDPreInstruction(llvm::MCInst &Inst,unsigned Insn,
305                                uint64_t Address, const void *Decoder);
306 static DecodeStatus DecodeT2Adr(llvm::MCInst &Inst, unsigned Val,
307                                 uint64_t Address, const void *Decoder);
308 static DecodeStatus DecodeT2LdStPre(llvm::MCInst &Inst, unsigned Val,
309                                 uint64_t Address, const void *Decoder);
310 static DecodeStatus DecodeT2ShifterImmOperand(llvm::MCInst &Inst, unsigned Val,
311                                 uint64_t Address, const void *Decoder);
312 
313 
314 
315 #include "ARMGenDisassemblerTables.inc"
316 #include "ARMGenInstrInfo.inc"
317 #include "ARMGenEDInfo.inc"
318 
319 static MCDisassembler *createARMDisassembler(const Target &T, const MCSubtargetInfo &STI) {
320   return new ARMDisassembler(STI);
321 }
322 
323 static MCDisassembler *createThumbDisassembler(const Target &T, const MCSubtargetInfo &STI) {
324   return new ThumbDisassembler(STI);
325 }
326 
327 EDInstInfo *ARMDisassembler::getEDInfo() const {
328   return instInfoARM;
329 }
330 
331 EDInstInfo *ThumbDisassembler::getEDInfo() const {
332   return instInfoARM;
333 }
334 
335 DecodeStatus ARMDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
336                                              const MemoryObject &Region,
337                                              uint64_t Address,
338                                              raw_ostream &os,
339                                              raw_ostream &cs) const {
340   uint8_t bytes[4];
341 
342   assert(!(STI.getFeatureBits() & ARM::ModeThumb) &&
343          "Asked to disassemble an ARM instruction but Subtarget is in Thumb mode!");
344 
345   // We want to read exactly 4 bytes of data.
346   if (Region.readBytes(Address, 4, (uint8_t*)bytes, NULL) == -1) {
347     Size = 0;
348     return MCDisassembler::Fail;
349   }
350 
351   // Encoded as a small-endian 32-bit word in the stream.
352   uint32_t insn = (bytes[3] << 24) |
353                   (bytes[2] << 16) |
354                   (bytes[1] <<  8) |
355                   (bytes[0] <<  0);
356 
357   // Calling the auto-generated decoder function.
358   DecodeStatus result = decodeARMInstruction32(MI, insn, Address, this, STI);
359   if (result != MCDisassembler::Fail) {
360     Size = 4;
361     return result;
362   }
363 
364   // VFP and NEON instructions, similarly, are shared between ARM
365   // and Thumb modes.
366   MI.clear();
367   result = decodeVFPInstruction32(MI, insn, Address, this, STI);
368   if (result != MCDisassembler::Fail) {
369     Size = 4;
370     return result;
371   }
372 
373   MI.clear();
374   result = decodeNEONDataInstruction32(MI, insn, Address, this, STI);
375   if (result != MCDisassembler::Fail) {
376     Size = 4;
377     // Add a fake predicate operand, because we share these instruction
378     // definitions with Thumb2 where these instructions are predicable.
379     if (!DecodePredicateOperand(MI, 0xE, Address, this))
380       return MCDisassembler::Fail;
381     return result;
382   }
383 
384   MI.clear();
385   result = decodeNEONLoadStoreInstruction32(MI, insn, Address, this, STI);
386   if (result != MCDisassembler::Fail) {
387     Size = 4;
388     // Add a fake predicate operand, because we share these instruction
389     // definitions with Thumb2 where these instructions are predicable.
390     if (!DecodePredicateOperand(MI, 0xE, Address, this))
391       return MCDisassembler::Fail;
392     return result;
393   }
394 
395   MI.clear();
396   result = decodeNEONDupInstruction32(MI, insn, Address, this, STI);
397   if (result != MCDisassembler::Fail) {
398     Size = 4;
399     // Add a fake predicate operand, because we share these instruction
400     // definitions with Thumb2 where these instructions are predicable.
401     if (!DecodePredicateOperand(MI, 0xE, Address, this))
402       return MCDisassembler::Fail;
403     return result;
404   }
405 
406   MI.clear();
407 
408   Size = 0;
409   return MCDisassembler::Fail;
410 }
411 
412 namespace llvm {
413 extern MCInstrDesc ARMInsts[];
414 }
415 
416 // Thumb1 instructions don't have explicit S bits.  Rather, they
417 // implicitly set CPSR.  Since it's not represented in the encoding, the
418 // auto-generated decoder won't inject the CPSR operand.  We need to fix
419 // that as a post-pass.
420 static void AddThumb1SBit(MCInst &MI, bool InITBlock) {
421   const MCOperandInfo *OpInfo = ARMInsts[MI.getOpcode()].OpInfo;
422   unsigned short NumOps = ARMInsts[MI.getOpcode()].NumOperands;
423   MCInst::iterator I = MI.begin();
424   for (unsigned i = 0; i < NumOps; ++i, ++I) {
425     if (I == MI.end()) break;
426     if (OpInfo[i].isOptionalDef() && OpInfo[i].RegClass == ARM::CCRRegClassID) {
427       if (i > 0 && OpInfo[i-1].isPredicate()) continue;
428       MI.insert(I, MCOperand::CreateReg(InITBlock ? 0 : ARM::CPSR));
429       return;
430     }
431   }
432 
433   MI.insert(I, MCOperand::CreateReg(InITBlock ? 0 : ARM::CPSR));
434 }
435 
436 // Most Thumb instructions don't have explicit predicates in the
437 // encoding, but rather get their predicates from IT context.  We need
438 // to fix up the predicate operands using this context information as a
439 // post-pass.
440 MCDisassembler::DecodeStatus
441 ThumbDisassembler::AddThumbPredicate(MCInst &MI) const {
442   MCDisassembler::DecodeStatus S = Success;
443 
444   // A few instructions actually have predicates encoded in them.  Don't
445   // try to overwrite it if we're seeing one of those.
446   switch (MI.getOpcode()) {
447     case ARM::tBcc:
448     case ARM::t2Bcc:
449     case ARM::tCBZ:
450     case ARM::tCBNZ:
451     case ARM::tCPS:
452     case ARM::t2CPS3p:
453     case ARM::t2CPS2p:
454     case ARM::t2CPS1p:
455     case ARM::tMOVSr:
456       // Some instructions (mostly conditional branches) are not
457       // allowed in IT blocks.
458       if (!ITBlock.empty())
459         S = SoftFail;
460       else
461         return Success;
462       break;
463     case ARM::tB:
464     case ARM::t2B:
465     case ARM::t2TBB:
466     case ARM::t2TBH:
467       // Some instructions (mostly unconditional branches) can
468       // only appears at the end of, or outside of, an IT.
469       if (ITBlock.size() > 1)
470         S = SoftFail;
471       break;
472     default:
473       break;
474   }
475 
476   // If we're in an IT block, base the predicate on that.  Otherwise,
477   // assume a predicate of AL.
478   unsigned CC;
479   if (!ITBlock.empty()) {
480     CC = ITBlock.back();
481     if (CC == 0xF)
482       CC = ARMCC::AL;
483     ITBlock.pop_back();
484   } else
485     CC = ARMCC::AL;
486 
487   const MCOperandInfo *OpInfo = ARMInsts[MI.getOpcode()].OpInfo;
488   unsigned short NumOps = ARMInsts[MI.getOpcode()].NumOperands;
489   MCInst::iterator I = MI.begin();
490   for (unsigned i = 0; i < NumOps; ++i, ++I) {
491     if (I == MI.end()) break;
492     if (OpInfo[i].isPredicate()) {
493       I = MI.insert(I, MCOperand::CreateImm(CC));
494       ++I;
495       if (CC == ARMCC::AL)
496         MI.insert(I, MCOperand::CreateReg(0));
497       else
498         MI.insert(I, MCOperand::CreateReg(ARM::CPSR));
499       return S;
500     }
501   }
502 
503   I = MI.insert(I, MCOperand::CreateImm(CC));
504   ++I;
505   if (CC == ARMCC::AL)
506     MI.insert(I, MCOperand::CreateReg(0));
507   else
508     MI.insert(I, MCOperand::CreateReg(ARM::CPSR));
509 
510   return S;
511 }
512 
513 // Thumb VFP instructions are a special case.  Because we share their
514 // encodings between ARM and Thumb modes, and they are predicable in ARM
515 // mode, the auto-generated decoder will give them an (incorrect)
516 // predicate operand.  We need to rewrite these operands based on the IT
517 // context as a post-pass.
518 void ThumbDisassembler::UpdateThumbVFPPredicate(MCInst &MI) const {
519   unsigned CC;
520   if (!ITBlock.empty()) {
521     CC = ITBlock.back();
522     ITBlock.pop_back();
523   } else
524     CC = ARMCC::AL;
525 
526   const MCOperandInfo *OpInfo = ARMInsts[MI.getOpcode()].OpInfo;
527   MCInst::iterator I = MI.begin();
528   unsigned short NumOps = ARMInsts[MI.getOpcode()].NumOperands;
529   for (unsigned i = 0; i < NumOps; ++i, ++I) {
530     if (OpInfo[i].isPredicate() ) {
531       I->setImm(CC);
532       ++I;
533       if (CC == ARMCC::AL)
534         I->setReg(0);
535       else
536         I->setReg(ARM::CPSR);
537       return;
538     }
539   }
540 }
541 
542 DecodeStatus ThumbDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
543                                                const MemoryObject &Region,
544                                                uint64_t Address,
545                                                raw_ostream &os,
546                                                raw_ostream &cs) const {
547   uint8_t bytes[4];
548 
549   assert((STI.getFeatureBits() & ARM::ModeThumb) &&
550          "Asked to disassemble in Thumb mode but Subtarget is in ARM mode!");
551 
552   // We want to read exactly 2 bytes of data.
553   if (Region.readBytes(Address, 2, (uint8_t*)bytes, NULL) == -1) {
554     Size = 0;
555     return MCDisassembler::Fail;
556   }
557 
558   uint16_t insn16 = (bytes[1] << 8) | bytes[0];
559   DecodeStatus result = decodeThumbInstruction16(MI, insn16, Address, this, STI);
560   if (result != MCDisassembler::Fail) {
561     Size = 2;
562     Check(result, AddThumbPredicate(MI));
563     return result;
564   }
565 
566   MI.clear();
567   result = decodeThumbSBitInstruction16(MI, insn16, Address, this, STI);
568   if (result) {
569     Size = 2;
570     bool InITBlock = !ITBlock.empty();
571     Check(result, AddThumbPredicate(MI));
572     AddThumb1SBit(MI, InITBlock);
573     return result;
574   }
575 
576   MI.clear();
577   result = decodeThumb2Instruction16(MI, insn16, Address, this, STI);
578   if (result != MCDisassembler::Fail) {
579     Size = 2;
580     Check(result, AddThumbPredicate(MI));
581 
582     // If we find an IT instruction, we need to parse its condition
583     // code and mask operands so that we can apply them correctly
584     // to the subsequent instructions.
585     if (MI.getOpcode() == ARM::t2IT) {
586       // Nested IT blocks are UNPREDICTABLE.
587       if (!ITBlock.empty())
588         return MCDisassembler::SoftFail;
589 
590       // (3 - the number of trailing zeros) is the number of then / else.
591       unsigned firstcond = MI.getOperand(0).getImm();
592       unsigned Mask = MI.getOperand(1).getImm();
593       unsigned CondBit0 = Mask >> 4 & 1;
594       unsigned NumTZ = CountTrailingZeros_32(Mask);
595       assert(NumTZ <= 3 && "Invalid IT mask!");
596       for (unsigned Pos = 3, e = NumTZ; Pos > e; --Pos) {
597         bool T = ((Mask >> Pos) & 1) == CondBit0;
598         if (T)
599           ITBlock.insert(ITBlock.begin(), firstcond);
600         else
601           ITBlock.insert(ITBlock.begin(), firstcond ^ 1);
602       }
603 
604       ITBlock.push_back(firstcond);
605     }
606 
607     return result;
608   }
609 
610   // We want to read exactly 4 bytes of data.
611   if (Region.readBytes(Address, 4, (uint8_t*)bytes, NULL) == -1) {
612     Size = 0;
613     return MCDisassembler::Fail;
614   }
615 
616   uint32_t insn32 = (bytes[3] <<  8) |
617                     (bytes[2] <<  0) |
618                     (bytes[1] << 24) |
619                     (bytes[0] << 16);
620   MI.clear();
621   result = decodeThumbInstruction32(MI, insn32, Address, this, STI);
622   if (result != MCDisassembler::Fail) {
623     Size = 4;
624     bool InITBlock = ITBlock.size();
625     Check(result, AddThumbPredicate(MI));
626     AddThumb1SBit(MI, InITBlock);
627     return result;
628   }
629 
630   MI.clear();
631   result = decodeThumb2Instruction32(MI, insn32, Address, this, STI);
632   if (result != MCDisassembler::Fail) {
633     Size = 4;
634     Check(result, AddThumbPredicate(MI));
635     return result;
636   }
637 
638   MI.clear();
639   result = decodeVFPInstruction32(MI, insn32, Address, this, STI);
640   if (result != MCDisassembler::Fail) {
641     Size = 4;
642     UpdateThumbVFPPredicate(MI);
643     return result;
644   }
645 
646   MI.clear();
647   result = decodeNEONDupInstruction32(MI, insn32, Address, this, STI);
648   if (result != MCDisassembler::Fail) {
649     Size = 4;
650     Check(result, AddThumbPredicate(MI));
651     return result;
652   }
653 
654   if (fieldFromInstruction32(insn32, 24, 8) == 0xF9) {
655     MI.clear();
656     uint32_t NEONLdStInsn = insn32;
657     NEONLdStInsn &= 0xF0FFFFFF;
658     NEONLdStInsn |= 0x04000000;
659     result = decodeNEONLoadStoreInstruction32(MI, NEONLdStInsn, Address, this, STI);
660     if (result != MCDisassembler::Fail) {
661       Size = 4;
662       Check(result, AddThumbPredicate(MI));
663       return result;
664     }
665   }
666 
667   if (fieldFromInstruction32(insn32, 24, 4) == 0xF) {
668     MI.clear();
669     uint32_t NEONDataInsn = insn32;
670     NEONDataInsn &= 0xF0FFFFFF; // Clear bits 27-24
671     NEONDataInsn |= (NEONDataInsn & 0x10000000) >> 4; // Move bit 28 to bit 24
672     NEONDataInsn |= 0x12000000; // Set bits 28 and 25
673     result = decodeNEONDataInstruction32(MI, NEONDataInsn, Address, this, STI);
674     if (result != MCDisassembler::Fail) {
675       Size = 4;
676       Check(result, AddThumbPredicate(MI));
677       return result;
678     }
679   }
680 
681   Size = 0;
682   return MCDisassembler::Fail;
683 }
684 
685 
686 extern "C" void LLVMInitializeARMDisassembler() {
687   TargetRegistry::RegisterMCDisassembler(TheARMTarget,
688                                          createARMDisassembler);
689   TargetRegistry::RegisterMCDisassembler(TheThumbTarget,
690                                          createThumbDisassembler);
691 }
692 
693 static const unsigned GPRDecoderTable[] = {
694   ARM::R0, ARM::R1, ARM::R2, ARM::R3,
695   ARM::R4, ARM::R5, ARM::R6, ARM::R7,
696   ARM::R8, ARM::R9, ARM::R10, ARM::R11,
697   ARM::R12, ARM::SP, ARM::LR, ARM::PC
698 };
699 
700 static DecodeStatus DecodeGPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
701                                    uint64_t Address, const void *Decoder) {
702   if (RegNo > 15)
703     return MCDisassembler::Fail;
704 
705   unsigned Register = GPRDecoderTable[RegNo];
706   Inst.addOperand(MCOperand::CreateReg(Register));
707   return MCDisassembler::Success;
708 }
709 
710 static DecodeStatus
711 DecodeGPRnopcRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
712                            uint64_t Address, const void *Decoder) {
713   if (RegNo == 15) return MCDisassembler::Fail;
714   return DecodeGPRRegisterClass(Inst, RegNo, Address, Decoder);
715 }
716 
717 static DecodeStatus DecodetGPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
718                                    uint64_t Address, const void *Decoder) {
719   if (RegNo > 7)
720     return MCDisassembler::Fail;
721   return DecodeGPRRegisterClass(Inst, RegNo, Address, Decoder);
722 }
723 
724 static DecodeStatus DecodetcGPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
725                                    uint64_t Address, const void *Decoder) {
726   unsigned Register = 0;
727   switch (RegNo) {
728     case 0:
729       Register = ARM::R0;
730       break;
731     case 1:
732       Register = ARM::R1;
733       break;
734     case 2:
735       Register = ARM::R2;
736       break;
737     case 3:
738       Register = ARM::R3;
739       break;
740     case 9:
741       Register = ARM::R9;
742       break;
743     case 12:
744       Register = ARM::R12;
745       break;
746     default:
747       return MCDisassembler::Fail;
748     }
749 
750   Inst.addOperand(MCOperand::CreateReg(Register));
751   return MCDisassembler::Success;
752 }
753 
754 static DecodeStatus DecoderGPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
755                                    uint64_t Address, const void *Decoder) {
756   if (RegNo == 13 || RegNo == 15) return MCDisassembler::Fail;
757   return DecodeGPRRegisterClass(Inst, RegNo, Address, Decoder);
758 }
759 
760 static const unsigned SPRDecoderTable[] = {
761      ARM::S0,  ARM::S1,  ARM::S2,  ARM::S3,
762      ARM::S4,  ARM::S5,  ARM::S6,  ARM::S7,
763      ARM::S8,  ARM::S9, ARM::S10, ARM::S11,
764     ARM::S12, ARM::S13, ARM::S14, ARM::S15,
765     ARM::S16, ARM::S17, ARM::S18, ARM::S19,
766     ARM::S20, ARM::S21, ARM::S22, ARM::S23,
767     ARM::S24, ARM::S25, ARM::S26, ARM::S27,
768     ARM::S28, ARM::S29, ARM::S30, ARM::S31
769 };
770 
771 static DecodeStatus DecodeSPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
772                                    uint64_t Address, const void *Decoder) {
773   if (RegNo > 31)
774     return MCDisassembler::Fail;
775 
776   unsigned Register = SPRDecoderTable[RegNo];
777   Inst.addOperand(MCOperand::CreateReg(Register));
778   return MCDisassembler::Success;
779 }
780 
781 static const unsigned DPRDecoderTable[] = {
782      ARM::D0,  ARM::D1,  ARM::D2,  ARM::D3,
783      ARM::D4,  ARM::D5,  ARM::D6,  ARM::D7,
784      ARM::D8,  ARM::D9, ARM::D10, ARM::D11,
785     ARM::D12, ARM::D13, ARM::D14, ARM::D15,
786     ARM::D16, ARM::D17, ARM::D18, ARM::D19,
787     ARM::D20, ARM::D21, ARM::D22, ARM::D23,
788     ARM::D24, ARM::D25, ARM::D26, ARM::D27,
789     ARM::D28, ARM::D29, ARM::D30, ARM::D31
790 };
791 
792 static DecodeStatus DecodeDPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
793                                    uint64_t Address, const void *Decoder) {
794   if (RegNo > 31)
795     return MCDisassembler::Fail;
796 
797   unsigned Register = DPRDecoderTable[RegNo];
798   Inst.addOperand(MCOperand::CreateReg(Register));
799   return MCDisassembler::Success;
800 }
801 
802 static DecodeStatus DecodeDPR_8RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
803                                    uint64_t Address, const void *Decoder) {
804   if (RegNo > 7)
805     return MCDisassembler::Fail;
806   return DecodeDPRRegisterClass(Inst, RegNo, Address, Decoder);
807 }
808 
809 static DecodeStatus
810 DecodeDPR_VFP2RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
811                             uint64_t Address, const void *Decoder) {
812   if (RegNo > 15)
813     return MCDisassembler::Fail;
814   return DecodeDPRRegisterClass(Inst, RegNo, Address, Decoder);
815 }
816 
817 static const unsigned QPRDecoderTable[] = {
818      ARM::Q0,  ARM::Q1,  ARM::Q2,  ARM::Q3,
819      ARM::Q4,  ARM::Q5,  ARM::Q6,  ARM::Q7,
820      ARM::Q8,  ARM::Q9, ARM::Q10, ARM::Q11,
821     ARM::Q12, ARM::Q13, ARM::Q14, ARM::Q15
822 };
823 
824 
825 static DecodeStatus DecodeQPRRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
826                                    uint64_t Address, const void *Decoder) {
827   if (RegNo > 31)
828     return MCDisassembler::Fail;
829   RegNo >>= 1;
830 
831   unsigned Register = QPRDecoderTable[RegNo];
832   Inst.addOperand(MCOperand::CreateReg(Register));
833   return MCDisassembler::Success;
834 }
835 
836 static DecodeStatus DecodePredicateOperand(llvm::MCInst &Inst, unsigned Val,
837                                uint64_t Address, const void *Decoder) {
838   if (Val == 0xF) return MCDisassembler::Fail;
839   // AL predicate is not allowed on Thumb1 branches.
840   if (Inst.getOpcode() == ARM::tBcc && Val == 0xE)
841     return MCDisassembler::Fail;
842   Inst.addOperand(MCOperand::CreateImm(Val));
843   if (Val == ARMCC::AL) {
844     Inst.addOperand(MCOperand::CreateReg(0));
845   } else
846     Inst.addOperand(MCOperand::CreateReg(ARM::CPSR));
847   return MCDisassembler::Success;
848 }
849 
850 static DecodeStatus DecodeCCOutOperand(llvm::MCInst &Inst, unsigned Val,
851                                uint64_t Address, const void *Decoder) {
852   if (Val)
853     Inst.addOperand(MCOperand::CreateReg(ARM::CPSR));
854   else
855     Inst.addOperand(MCOperand::CreateReg(0));
856   return MCDisassembler::Success;
857 }
858 
859 static DecodeStatus DecodeSOImmOperand(llvm::MCInst &Inst, unsigned Val,
860                                uint64_t Address, const void *Decoder) {
861   uint32_t imm = Val & 0xFF;
862   uint32_t rot = (Val & 0xF00) >> 7;
863   uint32_t rot_imm = (imm >> rot) | (imm << (32-rot));
864   Inst.addOperand(MCOperand::CreateImm(rot_imm));
865   return MCDisassembler::Success;
866 }
867 
868 static DecodeStatus DecodeSORegImmOperand(llvm::MCInst &Inst, unsigned Val,
869                                uint64_t Address, const void *Decoder) {
870   DecodeStatus S = MCDisassembler::Success;
871 
872   unsigned Rm = fieldFromInstruction32(Val, 0, 4);
873   unsigned type = fieldFromInstruction32(Val, 5, 2);
874   unsigned imm = fieldFromInstruction32(Val, 7, 5);
875 
876   // Register-immediate
877   if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
878     return MCDisassembler::Fail;
879 
880   ARM_AM::ShiftOpc Shift = ARM_AM::lsl;
881   switch (type) {
882     case 0:
883       Shift = ARM_AM::lsl;
884       break;
885     case 1:
886       Shift = ARM_AM::lsr;
887       break;
888     case 2:
889       Shift = ARM_AM::asr;
890       break;
891     case 3:
892       Shift = ARM_AM::ror;
893       break;
894   }
895 
896   if (Shift == ARM_AM::ror && imm == 0)
897     Shift = ARM_AM::rrx;
898 
899   unsigned Op = Shift | (imm << 3);
900   Inst.addOperand(MCOperand::CreateImm(Op));
901 
902   return S;
903 }
904 
905 static DecodeStatus DecodeSORegRegOperand(llvm::MCInst &Inst, unsigned Val,
906                                uint64_t Address, const void *Decoder) {
907   DecodeStatus S = MCDisassembler::Success;
908 
909   unsigned Rm = fieldFromInstruction32(Val, 0, 4);
910   unsigned type = fieldFromInstruction32(Val, 5, 2);
911   unsigned Rs = fieldFromInstruction32(Val, 8, 4);
912 
913   // Register-register
914   if (!Check(S, DecodeGPRnopcRegisterClass(Inst, Rm, Address, Decoder)))
915     return MCDisassembler::Fail;
916   if (!Check(S, DecodeGPRnopcRegisterClass(Inst, Rs, Address, Decoder)))
917     return MCDisassembler::Fail;
918 
919   ARM_AM::ShiftOpc Shift = ARM_AM::lsl;
920   switch (type) {
921     case 0:
922       Shift = ARM_AM::lsl;
923       break;
924     case 1:
925       Shift = ARM_AM::lsr;
926       break;
927     case 2:
928       Shift = ARM_AM::asr;
929       break;
930     case 3:
931       Shift = ARM_AM::ror;
932       break;
933   }
934 
935   Inst.addOperand(MCOperand::CreateImm(Shift));
936 
937   return S;
938 }
939 
940 static DecodeStatus DecodeRegListOperand(llvm::MCInst &Inst, unsigned Val,
941                                  uint64_t Address, const void *Decoder) {
942   DecodeStatus S = MCDisassembler::Success;
943 
944   bool writebackLoad = false;
945   unsigned writebackReg = 0;
946   switch (Inst.getOpcode()) {
947     default:
948       break;
949     case ARM::LDMIA_UPD:
950     case ARM::LDMDB_UPD:
951     case ARM::LDMIB_UPD:
952     case ARM::LDMDA_UPD:
953     case ARM::t2LDMIA_UPD:
954     case ARM::t2LDMDB_UPD:
955       writebackLoad = true;
956       writebackReg = Inst.getOperand(0).getReg();
957       break;
958   }
959 
960   // Empty register lists are not allowed.
961   if (CountPopulation_32(Val) == 0) return MCDisassembler::Fail;
962   for (unsigned i = 0; i < 16; ++i) {
963     if (Val & (1 << i)) {
964       if (!Check(S, DecodeGPRRegisterClass(Inst, i, Address, Decoder)))
965         return MCDisassembler::Fail;
966       // Writeback not allowed if Rn is in the target list.
967       if (writebackLoad && writebackReg == Inst.end()[-1].getReg())
968         Check(S, MCDisassembler::SoftFail);
969     }
970   }
971 
972   return S;
973 }
974 
975 static DecodeStatus DecodeSPRRegListOperand(llvm::MCInst &Inst, unsigned Val,
976                                  uint64_t Address, const void *Decoder) {
977   DecodeStatus S = MCDisassembler::Success;
978 
979   unsigned Vd = fieldFromInstruction32(Val, 8, 4);
980   unsigned regs = Val & 0xFF;
981 
982   if (!Check(S, DecodeSPRRegisterClass(Inst, Vd, Address, Decoder)))
983     return MCDisassembler::Fail;
984   for (unsigned i = 0; i < (regs - 1); ++i) {
985     if (!Check(S, DecodeSPRRegisterClass(Inst, ++Vd, Address, Decoder)))
986       return MCDisassembler::Fail;
987   }
988 
989   return S;
990 }
991 
992 static DecodeStatus DecodeDPRRegListOperand(llvm::MCInst &Inst, unsigned Val,
993                                  uint64_t Address, const void *Decoder) {
994   DecodeStatus S = MCDisassembler::Success;
995 
996   unsigned Vd = fieldFromInstruction32(Val, 8, 4);
997   unsigned regs = (Val & 0xFF) / 2;
998 
999   if (!Check(S, DecodeDPRRegisterClass(Inst, Vd, Address, Decoder)))
1000       return MCDisassembler::Fail;
1001   for (unsigned i = 0; i < (regs - 1); ++i) {
1002     if (!Check(S, DecodeDPRRegisterClass(Inst, ++Vd, Address, Decoder)))
1003       return MCDisassembler::Fail;
1004   }
1005 
1006   return S;
1007 }
1008 
1009 static DecodeStatus DecodeBitfieldMaskOperand(llvm::MCInst &Inst, unsigned Val,
1010                                       uint64_t Address, const void *Decoder) {
1011   // This operand encodes a mask of contiguous zeros between a specified MSB
1012   // and LSB.  To decode it, we create the mask of all bits MSB-and-lower,
1013   // the mask of all bits LSB-and-lower, and then xor them to create
1014   // the mask of that's all ones on [msb, lsb].  Finally we not it to
1015   // create the final mask.
1016   unsigned msb = fieldFromInstruction32(Val, 5, 5);
1017   unsigned lsb = fieldFromInstruction32(Val, 0, 5);
1018 
1019   DecodeStatus S = MCDisassembler::Success;
1020   if (lsb > msb) Check(S, MCDisassembler::SoftFail);
1021 
1022   uint32_t msb_mask = 0xFFFFFFFF;
1023   if (msb != 31) msb_mask = (1U << (msb+1)) - 1;
1024   uint32_t lsb_mask = (1U << lsb) - 1;
1025 
1026   Inst.addOperand(MCOperand::CreateImm(~(msb_mask ^ lsb_mask)));
1027   return S;
1028 }
1029 
1030 static DecodeStatus DecodeCopMemInstruction(llvm::MCInst &Inst, unsigned Insn,
1031                                   uint64_t Address, const void *Decoder) {
1032   DecodeStatus S = MCDisassembler::Success;
1033 
1034   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
1035   unsigned CRd = fieldFromInstruction32(Insn, 12, 4);
1036   unsigned coproc = fieldFromInstruction32(Insn, 8, 4);
1037   unsigned imm = fieldFromInstruction32(Insn, 0, 8);
1038   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
1039   unsigned U = fieldFromInstruction32(Insn, 23, 1);
1040 
1041   switch (Inst.getOpcode()) {
1042     case ARM::LDC_OFFSET:
1043     case ARM::LDC_PRE:
1044     case ARM::LDC_POST:
1045     case ARM::LDC_OPTION:
1046     case ARM::LDCL_OFFSET:
1047     case ARM::LDCL_PRE:
1048     case ARM::LDCL_POST:
1049     case ARM::LDCL_OPTION:
1050     case ARM::STC_OFFSET:
1051     case ARM::STC_PRE:
1052     case ARM::STC_POST:
1053     case ARM::STC_OPTION:
1054     case ARM::STCL_OFFSET:
1055     case ARM::STCL_PRE:
1056     case ARM::STCL_POST:
1057     case ARM::STCL_OPTION:
1058     case ARM::t2LDC_OFFSET:
1059     case ARM::t2LDC_PRE:
1060     case ARM::t2LDC_POST:
1061     case ARM::t2LDC_OPTION:
1062     case ARM::t2LDCL_OFFSET:
1063     case ARM::t2LDCL_PRE:
1064     case ARM::t2LDCL_POST:
1065     case ARM::t2LDCL_OPTION:
1066     case ARM::t2STC_OFFSET:
1067     case ARM::t2STC_PRE:
1068     case ARM::t2STC_POST:
1069     case ARM::t2STC_OPTION:
1070     case ARM::t2STCL_OFFSET:
1071     case ARM::t2STCL_PRE:
1072     case ARM::t2STCL_POST:
1073     case ARM::t2STCL_OPTION:
1074       if (coproc == 0xA || coproc == 0xB)
1075         return MCDisassembler::Fail;
1076       break;
1077     default:
1078       break;
1079   }
1080 
1081   Inst.addOperand(MCOperand::CreateImm(coproc));
1082   Inst.addOperand(MCOperand::CreateImm(CRd));
1083   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1084     return MCDisassembler::Fail;
1085   switch (Inst.getOpcode()) {
1086     case ARM::LDC_OPTION:
1087     case ARM::LDCL_OPTION:
1088     case ARM::LDC2_OPTION:
1089     case ARM::LDC2L_OPTION:
1090     case ARM::STC_OPTION:
1091     case ARM::STCL_OPTION:
1092     case ARM::STC2_OPTION:
1093     case ARM::STC2L_OPTION:
1094     case ARM::LDCL_POST:
1095     case ARM::STCL_POST:
1096     case ARM::LDC2L_POST:
1097     case ARM::STC2L_POST:
1098     case ARM::t2LDC_OPTION:
1099     case ARM::t2LDCL_OPTION:
1100     case ARM::t2STC_OPTION:
1101     case ARM::t2STCL_OPTION:
1102     case ARM::t2LDCL_POST:
1103     case ARM::t2STCL_POST:
1104       break;
1105     default:
1106       Inst.addOperand(MCOperand::CreateReg(0));
1107       break;
1108   }
1109 
1110   unsigned P = fieldFromInstruction32(Insn, 24, 1);
1111   unsigned W = fieldFromInstruction32(Insn, 21, 1);
1112 
1113   bool writeback = (P == 0) || (W == 1);
1114   unsigned idx_mode = 0;
1115   if (P && writeback)
1116     idx_mode = ARMII::IndexModePre;
1117   else if (!P && writeback)
1118     idx_mode = ARMII::IndexModePost;
1119 
1120   switch (Inst.getOpcode()) {
1121     case ARM::LDCL_POST:
1122     case ARM::STCL_POST:
1123     case ARM::t2LDCL_POST:
1124     case ARM::t2STCL_POST:
1125     case ARM::LDC2L_POST:
1126     case ARM::STC2L_POST:
1127       imm |= U << 8;
1128     case ARM::LDC_OPTION:
1129     case ARM::LDCL_OPTION:
1130     case ARM::LDC2_OPTION:
1131     case ARM::LDC2L_OPTION:
1132     case ARM::STC_OPTION:
1133     case ARM::STCL_OPTION:
1134     case ARM::STC2_OPTION:
1135     case ARM::STC2L_OPTION:
1136     case ARM::t2LDC_OPTION:
1137     case ARM::t2LDCL_OPTION:
1138     case ARM::t2STC_OPTION:
1139     case ARM::t2STCL_OPTION:
1140       Inst.addOperand(MCOperand::CreateImm(imm));
1141       break;
1142     default:
1143       if (U)
1144         Inst.addOperand(MCOperand::CreateImm(
1145             ARM_AM::getAM2Opc(ARM_AM::add, imm, ARM_AM::lsl, idx_mode)));
1146       else
1147         Inst.addOperand(MCOperand::CreateImm(
1148             ARM_AM::getAM2Opc(ARM_AM::sub, imm, ARM_AM::lsl, idx_mode)));
1149       break;
1150   }
1151 
1152   switch (Inst.getOpcode()) {
1153     case ARM::LDC_OFFSET:
1154     case ARM::LDC_PRE:
1155     case ARM::LDC_POST:
1156     case ARM::LDC_OPTION:
1157     case ARM::LDCL_OFFSET:
1158     case ARM::LDCL_PRE:
1159     case ARM::LDCL_POST:
1160     case ARM::LDCL_OPTION:
1161     case ARM::STC_OFFSET:
1162     case ARM::STC_PRE:
1163     case ARM::STC_POST:
1164     case ARM::STC_OPTION:
1165     case ARM::STCL_OFFSET:
1166     case ARM::STCL_PRE:
1167     case ARM::STCL_POST:
1168     case ARM::STCL_OPTION:
1169       if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
1170         return MCDisassembler::Fail;
1171       break;
1172     default:
1173       break;
1174   }
1175 
1176   return S;
1177 }
1178 
1179 static DecodeStatus
1180 DecodeAddrMode2IdxInstruction(llvm::MCInst &Inst, unsigned Insn,
1181                               uint64_t Address, const void *Decoder) {
1182   DecodeStatus S = MCDisassembler::Success;
1183 
1184   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
1185   unsigned Rt = fieldFromInstruction32(Insn, 12, 4);
1186   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
1187   unsigned imm = fieldFromInstruction32(Insn, 0, 12);
1188   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
1189   unsigned reg = fieldFromInstruction32(Insn, 25, 1);
1190   unsigned P = fieldFromInstruction32(Insn, 24, 1);
1191   unsigned W = fieldFromInstruction32(Insn, 21, 1);
1192 
1193   // On stores, the writeback operand precedes Rt.
1194   switch (Inst.getOpcode()) {
1195     case ARM::STR_POST_IMM:
1196     case ARM::STR_POST_REG:
1197     case ARM::STRB_POST_IMM:
1198     case ARM::STRB_POST_REG:
1199     case ARM::STRT_POST_REG:
1200     case ARM::STRT_POST_IMM:
1201     case ARM::STRBT_POST_REG:
1202     case ARM::STRBT_POST_IMM:
1203       if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1204         return MCDisassembler::Fail;
1205       break;
1206     default:
1207       break;
1208   }
1209 
1210   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt, Address, Decoder)))
1211     return MCDisassembler::Fail;
1212 
1213   // On loads, the writeback operand comes after Rt.
1214   switch (Inst.getOpcode()) {
1215     case ARM::LDR_POST_IMM:
1216     case ARM::LDR_POST_REG:
1217     case ARM::LDRB_POST_IMM:
1218     case ARM::LDRB_POST_REG:
1219     case ARM::LDRBT_POST_REG:
1220     case ARM::LDRBT_POST_IMM:
1221     case ARM::LDRT_POST_REG:
1222     case ARM::LDRT_POST_IMM:
1223       if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1224         return MCDisassembler::Fail;
1225       break;
1226     default:
1227       break;
1228   }
1229 
1230   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1231     return MCDisassembler::Fail;
1232 
1233   ARM_AM::AddrOpc Op = ARM_AM::add;
1234   if (!fieldFromInstruction32(Insn, 23, 1))
1235     Op = ARM_AM::sub;
1236 
1237   bool writeback = (P == 0) || (W == 1);
1238   unsigned idx_mode = 0;
1239   if (P && writeback)
1240     idx_mode = ARMII::IndexModePre;
1241   else if (!P && writeback)
1242     idx_mode = ARMII::IndexModePost;
1243 
1244   if (writeback && (Rn == 15 || Rn == Rt))
1245     S = MCDisassembler::SoftFail; // UNPREDICTABLE
1246 
1247   if (reg) {
1248     if (!Check(S, DecodeGPRnopcRegisterClass(Inst, Rm, Address, Decoder)))
1249       return MCDisassembler::Fail;
1250     ARM_AM::ShiftOpc Opc = ARM_AM::lsl;
1251     switch( fieldFromInstruction32(Insn, 5, 2)) {
1252       case 0:
1253         Opc = ARM_AM::lsl;
1254         break;
1255       case 1:
1256         Opc = ARM_AM::lsr;
1257         break;
1258       case 2:
1259         Opc = ARM_AM::asr;
1260         break;
1261       case 3:
1262         Opc = ARM_AM::ror;
1263         break;
1264       default:
1265         return MCDisassembler::Fail;
1266     }
1267     unsigned amt = fieldFromInstruction32(Insn, 7, 5);
1268     unsigned imm = ARM_AM::getAM2Opc(Op, amt, Opc, idx_mode);
1269 
1270     Inst.addOperand(MCOperand::CreateImm(imm));
1271   } else {
1272     Inst.addOperand(MCOperand::CreateReg(0));
1273     unsigned tmp = ARM_AM::getAM2Opc(Op, imm, ARM_AM::lsl, idx_mode);
1274     Inst.addOperand(MCOperand::CreateImm(tmp));
1275   }
1276 
1277   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
1278     return MCDisassembler::Fail;
1279 
1280   return S;
1281 }
1282 
1283 static DecodeStatus DecodeSORegMemOperand(llvm::MCInst &Inst, unsigned Val,
1284                                   uint64_t Address, const void *Decoder) {
1285   DecodeStatus S = MCDisassembler::Success;
1286 
1287   unsigned Rn = fieldFromInstruction32(Val, 13, 4);
1288   unsigned Rm = fieldFromInstruction32(Val,  0, 4);
1289   unsigned type = fieldFromInstruction32(Val, 5, 2);
1290   unsigned imm = fieldFromInstruction32(Val, 7, 5);
1291   unsigned U = fieldFromInstruction32(Val, 12, 1);
1292 
1293   ARM_AM::ShiftOpc ShOp = ARM_AM::lsl;
1294   switch (type) {
1295     case 0:
1296       ShOp = ARM_AM::lsl;
1297       break;
1298     case 1:
1299       ShOp = ARM_AM::lsr;
1300       break;
1301     case 2:
1302       ShOp = ARM_AM::asr;
1303       break;
1304     case 3:
1305       ShOp = ARM_AM::ror;
1306       break;
1307   }
1308 
1309   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1310     return MCDisassembler::Fail;
1311   if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
1312     return MCDisassembler::Fail;
1313   unsigned shift;
1314   if (U)
1315     shift = ARM_AM::getAM2Opc(ARM_AM::add, imm, ShOp);
1316   else
1317     shift = ARM_AM::getAM2Opc(ARM_AM::sub, imm, ShOp);
1318   Inst.addOperand(MCOperand::CreateImm(shift));
1319 
1320   return S;
1321 }
1322 
1323 static DecodeStatus
1324 DecodeAddrMode3Instruction(llvm::MCInst &Inst, unsigned Insn,
1325                            uint64_t Address, const void *Decoder) {
1326   DecodeStatus S = MCDisassembler::Success;
1327 
1328   unsigned Rt = fieldFromInstruction32(Insn, 12, 4);
1329   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
1330   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
1331   unsigned type = fieldFromInstruction32(Insn, 22, 1);
1332   unsigned imm = fieldFromInstruction32(Insn, 8, 4);
1333   unsigned U = ((~fieldFromInstruction32(Insn, 23, 1)) & 1) << 8;
1334   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
1335   unsigned W = fieldFromInstruction32(Insn, 21, 1);
1336   unsigned P = fieldFromInstruction32(Insn, 24, 1);
1337 
1338   bool writeback = (W == 1) | (P == 0);
1339 
1340   // For {LD,ST}RD, Rt must be even, else undefined.
1341   switch (Inst.getOpcode()) {
1342     case ARM::STRD:
1343     case ARM::STRD_PRE:
1344     case ARM::STRD_POST:
1345     case ARM::LDRD:
1346     case ARM::LDRD_PRE:
1347     case ARM::LDRD_POST:
1348       if (Rt & 0x1) return MCDisassembler::Fail;
1349       break;
1350     default:
1351       break;
1352   }
1353 
1354   if (writeback) { // Writeback
1355     if (P)
1356       U |= ARMII::IndexModePre << 9;
1357     else
1358       U |= ARMII::IndexModePost << 9;
1359 
1360     // On stores, the writeback operand precedes Rt.
1361     switch (Inst.getOpcode()) {
1362     case ARM::STRD:
1363     case ARM::STRD_PRE:
1364     case ARM::STRD_POST:
1365     case ARM::STRH:
1366     case ARM::STRH_PRE:
1367     case ARM::STRH_POST:
1368       if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1369         return MCDisassembler::Fail;
1370       break;
1371     default:
1372       break;
1373     }
1374   }
1375 
1376   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt, Address, Decoder)))
1377     return MCDisassembler::Fail;
1378   switch (Inst.getOpcode()) {
1379     case ARM::STRD:
1380     case ARM::STRD_PRE:
1381     case ARM::STRD_POST:
1382     case ARM::LDRD:
1383     case ARM::LDRD_PRE:
1384     case ARM::LDRD_POST:
1385       if (!Check(S, DecodeGPRRegisterClass(Inst, Rt+1, Address, Decoder)))
1386         return MCDisassembler::Fail;
1387       break;
1388     default:
1389       break;
1390   }
1391 
1392   if (writeback) {
1393     // On loads, the writeback operand comes after Rt.
1394     switch (Inst.getOpcode()) {
1395     case ARM::LDRD:
1396     case ARM::LDRD_PRE:
1397     case ARM::LDRD_POST:
1398     case ARM::LDRH:
1399     case ARM::LDRH_PRE:
1400     case ARM::LDRH_POST:
1401     case ARM::LDRSH:
1402     case ARM::LDRSH_PRE:
1403     case ARM::LDRSH_POST:
1404     case ARM::LDRSB:
1405     case ARM::LDRSB_PRE:
1406     case ARM::LDRSB_POST:
1407     case ARM::LDRHTr:
1408     case ARM::LDRSBTr:
1409       if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1410         return MCDisassembler::Fail;
1411       break;
1412     default:
1413       break;
1414     }
1415   }
1416 
1417   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1418     return MCDisassembler::Fail;
1419 
1420   if (type) {
1421     Inst.addOperand(MCOperand::CreateReg(0));
1422     Inst.addOperand(MCOperand::CreateImm(U | (imm << 4) | Rm));
1423   } else {
1424     if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
1425     return MCDisassembler::Fail;
1426     Inst.addOperand(MCOperand::CreateImm(U));
1427   }
1428 
1429   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
1430     return MCDisassembler::Fail;
1431 
1432   return S;
1433 }
1434 
1435 static DecodeStatus DecodeRFEInstruction(llvm::MCInst &Inst, unsigned Insn,
1436                                  uint64_t Address, const void *Decoder) {
1437   DecodeStatus S = MCDisassembler::Success;
1438 
1439   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
1440   unsigned mode = fieldFromInstruction32(Insn, 23, 2);
1441 
1442   switch (mode) {
1443     case 0:
1444       mode = ARM_AM::da;
1445       break;
1446     case 1:
1447       mode = ARM_AM::ia;
1448       break;
1449     case 2:
1450       mode = ARM_AM::db;
1451       break;
1452     case 3:
1453       mode = ARM_AM::ib;
1454       break;
1455   }
1456 
1457   Inst.addOperand(MCOperand::CreateImm(mode));
1458   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1459     return MCDisassembler::Fail;
1460 
1461   return S;
1462 }
1463 
1464 static DecodeStatus DecodeMemMultipleWritebackInstruction(llvm::MCInst &Inst,
1465                                   unsigned Insn,
1466                                   uint64_t Address, const void *Decoder) {
1467   DecodeStatus S = MCDisassembler::Success;
1468 
1469   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
1470   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
1471   unsigned reglist = fieldFromInstruction32(Insn, 0, 16);
1472 
1473   if (pred == 0xF) {
1474     switch (Inst.getOpcode()) {
1475       case ARM::LDMDA:
1476         Inst.setOpcode(ARM::RFEDA);
1477         break;
1478       case ARM::LDMDA_UPD:
1479         Inst.setOpcode(ARM::RFEDA_UPD);
1480         break;
1481       case ARM::LDMDB:
1482         Inst.setOpcode(ARM::RFEDB);
1483         break;
1484       case ARM::LDMDB_UPD:
1485         Inst.setOpcode(ARM::RFEDB_UPD);
1486         break;
1487       case ARM::LDMIA:
1488         Inst.setOpcode(ARM::RFEIA);
1489         break;
1490       case ARM::LDMIA_UPD:
1491         Inst.setOpcode(ARM::RFEIA_UPD);
1492         break;
1493       case ARM::LDMIB:
1494         Inst.setOpcode(ARM::RFEIB);
1495         break;
1496       case ARM::LDMIB_UPD:
1497         Inst.setOpcode(ARM::RFEIB_UPD);
1498         break;
1499       case ARM::STMDA:
1500         Inst.setOpcode(ARM::SRSDA);
1501         break;
1502       case ARM::STMDA_UPD:
1503         Inst.setOpcode(ARM::SRSDA_UPD);
1504         break;
1505       case ARM::STMDB:
1506         Inst.setOpcode(ARM::SRSDB);
1507         break;
1508       case ARM::STMDB_UPD:
1509         Inst.setOpcode(ARM::SRSDB_UPD);
1510         break;
1511       case ARM::STMIA:
1512         Inst.setOpcode(ARM::SRSIA);
1513         break;
1514       case ARM::STMIA_UPD:
1515         Inst.setOpcode(ARM::SRSIA_UPD);
1516         break;
1517       case ARM::STMIB:
1518         Inst.setOpcode(ARM::SRSIB);
1519         break;
1520       case ARM::STMIB_UPD:
1521         Inst.setOpcode(ARM::SRSIB_UPD);
1522         break;
1523       default:
1524         if (!Check(S, MCDisassembler::Fail)) return MCDisassembler::Fail;
1525     }
1526 
1527     // For stores (which become SRS's, the only operand is the mode.
1528     if (fieldFromInstruction32(Insn, 20, 1) == 0) {
1529       Inst.addOperand(
1530           MCOperand::CreateImm(fieldFromInstruction32(Insn, 0, 4)));
1531       return S;
1532     }
1533 
1534     return DecodeRFEInstruction(Inst, Insn, Address, Decoder);
1535   }
1536 
1537   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1538     return MCDisassembler::Fail;
1539   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1540     return MCDisassembler::Fail; // Tied
1541   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
1542     return MCDisassembler::Fail;
1543   if (!Check(S, DecodeRegListOperand(Inst, reglist, Address, Decoder)))
1544     return MCDisassembler::Fail;
1545 
1546   return S;
1547 }
1548 
1549 static DecodeStatus DecodeCPSInstruction(llvm::MCInst &Inst, unsigned Insn,
1550                                  uint64_t Address, const void *Decoder) {
1551   unsigned imod = fieldFromInstruction32(Insn, 18, 2);
1552   unsigned M = fieldFromInstruction32(Insn, 17, 1);
1553   unsigned iflags = fieldFromInstruction32(Insn, 6, 3);
1554   unsigned mode = fieldFromInstruction32(Insn, 0, 5);
1555 
1556   DecodeStatus S = MCDisassembler::Success;
1557 
1558   // imod == '01' --> UNPREDICTABLE
1559   // NOTE: Even though this is technically UNPREDICTABLE, we choose to
1560   // return failure here.  The '01' imod value is unprintable, so there's
1561   // nothing useful we could do even if we returned UNPREDICTABLE.
1562 
1563   if (imod == 1) return MCDisassembler::Fail;
1564 
1565   if (imod && M) {
1566     Inst.setOpcode(ARM::CPS3p);
1567     Inst.addOperand(MCOperand::CreateImm(imod));
1568     Inst.addOperand(MCOperand::CreateImm(iflags));
1569     Inst.addOperand(MCOperand::CreateImm(mode));
1570   } else if (imod && !M) {
1571     Inst.setOpcode(ARM::CPS2p);
1572     Inst.addOperand(MCOperand::CreateImm(imod));
1573     Inst.addOperand(MCOperand::CreateImm(iflags));
1574     if (mode) S = MCDisassembler::SoftFail;
1575   } else if (!imod && M) {
1576     Inst.setOpcode(ARM::CPS1p);
1577     Inst.addOperand(MCOperand::CreateImm(mode));
1578     if (iflags) S = MCDisassembler::SoftFail;
1579   } else {
1580     // imod == '00' && M == '0' --> UNPREDICTABLE
1581     Inst.setOpcode(ARM::CPS1p);
1582     Inst.addOperand(MCOperand::CreateImm(mode));
1583     S = MCDisassembler::SoftFail;
1584   }
1585 
1586   return S;
1587 }
1588 
1589 static DecodeStatus DecodeT2CPSInstruction(llvm::MCInst &Inst, unsigned Insn,
1590                                  uint64_t Address, const void *Decoder) {
1591   unsigned imod = fieldFromInstruction32(Insn, 9, 2);
1592   unsigned M = fieldFromInstruction32(Insn, 8, 1);
1593   unsigned iflags = fieldFromInstruction32(Insn, 5, 3);
1594   unsigned mode = fieldFromInstruction32(Insn, 0, 5);
1595 
1596   DecodeStatus S = MCDisassembler::Success;
1597 
1598   // imod == '01' --> UNPREDICTABLE
1599   // NOTE: Even though this is technically UNPREDICTABLE, we choose to
1600   // return failure here.  The '01' imod value is unprintable, so there's
1601   // nothing useful we could do even if we returned UNPREDICTABLE.
1602 
1603   if (imod == 1) return MCDisassembler::Fail;
1604 
1605   if (imod && M) {
1606     Inst.setOpcode(ARM::t2CPS3p);
1607     Inst.addOperand(MCOperand::CreateImm(imod));
1608     Inst.addOperand(MCOperand::CreateImm(iflags));
1609     Inst.addOperand(MCOperand::CreateImm(mode));
1610   } else if (imod && !M) {
1611     Inst.setOpcode(ARM::t2CPS2p);
1612     Inst.addOperand(MCOperand::CreateImm(imod));
1613     Inst.addOperand(MCOperand::CreateImm(iflags));
1614     if (mode) S = MCDisassembler::SoftFail;
1615   } else if (!imod && M) {
1616     Inst.setOpcode(ARM::t2CPS1p);
1617     Inst.addOperand(MCOperand::CreateImm(mode));
1618     if (iflags) S = MCDisassembler::SoftFail;
1619   } else {
1620     // imod == '00' && M == '0' --> UNPREDICTABLE
1621     Inst.setOpcode(ARM::t2CPS1p);
1622     Inst.addOperand(MCOperand::CreateImm(mode));
1623     S = MCDisassembler::SoftFail;
1624   }
1625 
1626   return S;
1627 }
1628 
1629 
1630 static DecodeStatus DecodeSMLAInstruction(llvm::MCInst &Inst, unsigned Insn,
1631                                  uint64_t Address, const void *Decoder) {
1632   DecodeStatus S = MCDisassembler::Success;
1633 
1634   unsigned Rd = fieldFromInstruction32(Insn, 16, 4);
1635   unsigned Rn = fieldFromInstruction32(Insn, 0, 4);
1636   unsigned Rm = fieldFromInstruction32(Insn, 8, 4);
1637   unsigned Ra = fieldFromInstruction32(Insn, 12, 4);
1638   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
1639 
1640   if (pred == 0xF)
1641     return DecodeCPSInstruction(Inst, Insn, Address, Decoder);
1642 
1643   if (!Check(S, DecodeGPRnopcRegisterClass(Inst, Rd, Address, Decoder)))
1644     return MCDisassembler::Fail;
1645   if (!Check(S, DecodeGPRnopcRegisterClass(Inst, Rn, Address, Decoder)))
1646     return MCDisassembler::Fail;
1647   if (!Check(S, DecodeGPRnopcRegisterClass(Inst, Rm, Address, Decoder)))
1648     return MCDisassembler::Fail;
1649   if (!Check(S, DecodeGPRnopcRegisterClass(Inst, Ra, Address, Decoder)))
1650     return MCDisassembler::Fail;
1651 
1652   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
1653     return MCDisassembler::Fail;
1654 
1655   return S;
1656 }
1657 
1658 static DecodeStatus DecodeAddrModeImm12Operand(llvm::MCInst &Inst, unsigned Val,
1659                            uint64_t Address, const void *Decoder) {
1660   DecodeStatus S = MCDisassembler::Success;
1661 
1662   unsigned add = fieldFromInstruction32(Val, 12, 1);
1663   unsigned imm = fieldFromInstruction32(Val, 0, 12);
1664   unsigned Rn = fieldFromInstruction32(Val, 13, 4);
1665 
1666   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1667     return MCDisassembler::Fail;
1668 
1669   if (!add) imm *= -1;
1670   if (imm == 0 && !add) imm = INT32_MIN;
1671   Inst.addOperand(MCOperand::CreateImm(imm));
1672 
1673   return S;
1674 }
1675 
1676 static DecodeStatus DecodeAddrMode5Operand(llvm::MCInst &Inst, unsigned Val,
1677                                    uint64_t Address, const void *Decoder) {
1678   DecodeStatus S = MCDisassembler::Success;
1679 
1680   unsigned Rn = fieldFromInstruction32(Val, 9, 4);
1681   unsigned U = fieldFromInstruction32(Val, 8, 1);
1682   unsigned imm = fieldFromInstruction32(Val, 0, 8);
1683 
1684   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
1685     return MCDisassembler::Fail;
1686 
1687   if (U)
1688     Inst.addOperand(MCOperand::CreateImm(ARM_AM::getAM5Opc(ARM_AM::add, imm)));
1689   else
1690     Inst.addOperand(MCOperand::CreateImm(ARM_AM::getAM5Opc(ARM_AM::sub, imm)));
1691 
1692   return S;
1693 }
1694 
1695 static DecodeStatus DecodeAddrMode7Operand(llvm::MCInst &Inst, unsigned Val,
1696                                    uint64_t Address, const void *Decoder) {
1697   return DecodeGPRRegisterClass(Inst, Val, Address, Decoder);
1698 }
1699 
1700 static DecodeStatus
1701 DecodeBranchImmInstruction(llvm::MCInst &Inst, unsigned Insn,
1702                            uint64_t Address, const void *Decoder) {
1703   DecodeStatus S = MCDisassembler::Success;
1704 
1705   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
1706   unsigned imm = fieldFromInstruction32(Insn, 0, 24) << 2;
1707 
1708   if (pred == 0xF) {
1709     Inst.setOpcode(ARM::BLXi);
1710     imm |= fieldFromInstruction32(Insn, 24, 1) << 1;
1711     Inst.addOperand(MCOperand::CreateImm(SignExtend32<26>(imm)));
1712     return S;
1713   }
1714 
1715   Inst.addOperand(MCOperand::CreateImm(SignExtend32<26>(imm)));
1716   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
1717     return MCDisassembler::Fail;
1718 
1719   return S;
1720 }
1721 
1722 
1723 static DecodeStatus DecodeVCVTImmOperand(llvm::MCInst &Inst, unsigned Val,
1724                                  uint64_t Address, const void *Decoder) {
1725   Inst.addOperand(MCOperand::CreateImm(64 - Val));
1726   return MCDisassembler::Success;
1727 }
1728 
1729 static DecodeStatus DecodeAddrMode6Operand(llvm::MCInst &Inst, unsigned Val,
1730                                    uint64_t Address, const void *Decoder) {
1731   DecodeStatus S = MCDisassembler::Success;
1732 
1733   unsigned Rm = fieldFromInstruction32(Val, 0, 4);
1734   unsigned align = fieldFromInstruction32(Val, 4, 2);
1735 
1736   if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
1737     return MCDisassembler::Fail;
1738   if (!align)
1739     Inst.addOperand(MCOperand::CreateImm(0));
1740   else
1741     Inst.addOperand(MCOperand::CreateImm(4 << align));
1742 
1743   return S;
1744 }
1745 
1746 static DecodeStatus DecodeVLDInstruction(llvm::MCInst &Inst, unsigned Insn,
1747                                    uint64_t Address, const void *Decoder) {
1748   DecodeStatus S = MCDisassembler::Success;
1749 
1750   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
1751   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
1752   unsigned wb = fieldFromInstruction32(Insn, 16, 4);
1753   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
1754   Rn |= fieldFromInstruction32(Insn, 4, 2) << 4;
1755   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
1756 
1757   // First output register
1758   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
1759     return MCDisassembler::Fail;
1760 
1761   // Second output register
1762   switch (Inst.getOpcode()) {
1763     case ARM::VLD1q8:
1764     case ARM::VLD1q16:
1765     case ARM::VLD1q32:
1766     case ARM::VLD1q64:
1767     case ARM::VLD1q8_UPD:
1768     case ARM::VLD1q16_UPD:
1769     case ARM::VLD1q32_UPD:
1770     case ARM::VLD1q64_UPD:
1771     case ARM::VLD1d8T:
1772     case ARM::VLD1d16T:
1773     case ARM::VLD1d32T:
1774     case ARM::VLD1d64T:
1775     case ARM::VLD1d8T_UPD:
1776     case ARM::VLD1d16T_UPD:
1777     case ARM::VLD1d32T_UPD:
1778     case ARM::VLD1d64T_UPD:
1779     case ARM::VLD1d8Q:
1780     case ARM::VLD1d16Q:
1781     case ARM::VLD1d32Q:
1782     case ARM::VLD1d64Q:
1783     case ARM::VLD1d8Q_UPD:
1784     case ARM::VLD1d16Q_UPD:
1785     case ARM::VLD1d32Q_UPD:
1786     case ARM::VLD1d64Q_UPD:
1787     case ARM::VLD2d8:
1788     case ARM::VLD2d16:
1789     case ARM::VLD2d32:
1790     case ARM::VLD2d8_UPD:
1791     case ARM::VLD2d16_UPD:
1792     case ARM::VLD2d32_UPD:
1793     case ARM::VLD2q8:
1794     case ARM::VLD2q16:
1795     case ARM::VLD2q32:
1796     case ARM::VLD2q8_UPD:
1797     case ARM::VLD2q16_UPD:
1798     case ARM::VLD2q32_UPD:
1799     case ARM::VLD3d8:
1800     case ARM::VLD3d16:
1801     case ARM::VLD3d32:
1802     case ARM::VLD3d8_UPD:
1803     case ARM::VLD3d16_UPD:
1804     case ARM::VLD3d32_UPD:
1805     case ARM::VLD4d8:
1806     case ARM::VLD4d16:
1807     case ARM::VLD4d32:
1808     case ARM::VLD4d8_UPD:
1809     case ARM::VLD4d16_UPD:
1810     case ARM::VLD4d32_UPD:
1811       if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+1)%32, Address, Decoder)))
1812         return MCDisassembler::Fail;
1813       break;
1814     case ARM::VLD2b8:
1815     case ARM::VLD2b16:
1816     case ARM::VLD2b32:
1817     case ARM::VLD2b8_UPD:
1818     case ARM::VLD2b16_UPD:
1819     case ARM::VLD2b32_UPD:
1820     case ARM::VLD3q8:
1821     case ARM::VLD3q16:
1822     case ARM::VLD3q32:
1823     case ARM::VLD3q8_UPD:
1824     case ARM::VLD3q16_UPD:
1825     case ARM::VLD3q32_UPD:
1826     case ARM::VLD4q8:
1827     case ARM::VLD4q16:
1828     case ARM::VLD4q32:
1829     case ARM::VLD4q8_UPD:
1830     case ARM::VLD4q16_UPD:
1831     case ARM::VLD4q32_UPD:
1832       if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+2)%32, Address, Decoder)))
1833         return MCDisassembler::Fail;
1834     default:
1835       break;
1836   }
1837 
1838   // Third output register
1839   switch(Inst.getOpcode()) {
1840     case ARM::VLD1d8T:
1841     case ARM::VLD1d16T:
1842     case ARM::VLD1d32T:
1843     case ARM::VLD1d64T:
1844     case ARM::VLD1d8T_UPD:
1845     case ARM::VLD1d16T_UPD:
1846     case ARM::VLD1d32T_UPD:
1847     case ARM::VLD1d64T_UPD:
1848     case ARM::VLD1d8Q:
1849     case ARM::VLD1d16Q:
1850     case ARM::VLD1d32Q:
1851     case ARM::VLD1d64Q:
1852     case ARM::VLD1d8Q_UPD:
1853     case ARM::VLD1d16Q_UPD:
1854     case ARM::VLD1d32Q_UPD:
1855     case ARM::VLD1d64Q_UPD:
1856     case ARM::VLD2q8:
1857     case ARM::VLD2q16:
1858     case ARM::VLD2q32:
1859     case ARM::VLD2q8_UPD:
1860     case ARM::VLD2q16_UPD:
1861     case ARM::VLD2q32_UPD:
1862     case ARM::VLD3d8:
1863     case ARM::VLD3d16:
1864     case ARM::VLD3d32:
1865     case ARM::VLD3d8_UPD:
1866     case ARM::VLD3d16_UPD:
1867     case ARM::VLD3d32_UPD:
1868     case ARM::VLD4d8:
1869     case ARM::VLD4d16:
1870     case ARM::VLD4d32:
1871     case ARM::VLD4d8_UPD:
1872     case ARM::VLD4d16_UPD:
1873     case ARM::VLD4d32_UPD:
1874       if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+2)%32, Address, Decoder)))
1875         return MCDisassembler::Fail;
1876       break;
1877     case ARM::VLD3q8:
1878     case ARM::VLD3q16:
1879     case ARM::VLD3q32:
1880     case ARM::VLD3q8_UPD:
1881     case ARM::VLD3q16_UPD:
1882     case ARM::VLD3q32_UPD:
1883     case ARM::VLD4q8:
1884     case ARM::VLD4q16:
1885     case ARM::VLD4q32:
1886     case ARM::VLD4q8_UPD:
1887     case ARM::VLD4q16_UPD:
1888     case ARM::VLD4q32_UPD:
1889       if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+4)%32, Address, Decoder)))
1890         return MCDisassembler::Fail;
1891       break;
1892     default:
1893       break;
1894   }
1895 
1896   // Fourth output register
1897   switch (Inst.getOpcode()) {
1898     case ARM::VLD1d8Q:
1899     case ARM::VLD1d16Q:
1900     case ARM::VLD1d32Q:
1901     case ARM::VLD1d64Q:
1902     case ARM::VLD1d8Q_UPD:
1903     case ARM::VLD1d16Q_UPD:
1904     case ARM::VLD1d32Q_UPD:
1905     case ARM::VLD1d64Q_UPD:
1906     case ARM::VLD2q8:
1907     case ARM::VLD2q16:
1908     case ARM::VLD2q32:
1909     case ARM::VLD2q8_UPD:
1910     case ARM::VLD2q16_UPD:
1911     case ARM::VLD2q32_UPD:
1912     case ARM::VLD4d8:
1913     case ARM::VLD4d16:
1914     case ARM::VLD4d32:
1915     case ARM::VLD4d8_UPD:
1916     case ARM::VLD4d16_UPD:
1917     case ARM::VLD4d32_UPD:
1918       if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+3)%32, Address, Decoder)))
1919         return MCDisassembler::Fail;
1920       break;
1921     case ARM::VLD4q8:
1922     case ARM::VLD4q16:
1923     case ARM::VLD4q32:
1924     case ARM::VLD4q8_UPD:
1925     case ARM::VLD4q16_UPD:
1926     case ARM::VLD4q32_UPD:
1927       if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+6)%32, Address, Decoder)))
1928         return MCDisassembler::Fail;
1929       break;
1930     default:
1931       break;
1932   }
1933 
1934   // Writeback operand
1935   switch (Inst.getOpcode()) {
1936     case ARM::VLD1d8_UPD:
1937     case ARM::VLD1d16_UPD:
1938     case ARM::VLD1d32_UPD:
1939     case ARM::VLD1d64_UPD:
1940     case ARM::VLD1q8_UPD:
1941     case ARM::VLD1q16_UPD:
1942     case ARM::VLD1q32_UPD:
1943     case ARM::VLD1q64_UPD:
1944     case ARM::VLD1d8T_UPD:
1945     case ARM::VLD1d16T_UPD:
1946     case ARM::VLD1d32T_UPD:
1947     case ARM::VLD1d64T_UPD:
1948     case ARM::VLD1d8Q_UPD:
1949     case ARM::VLD1d16Q_UPD:
1950     case ARM::VLD1d32Q_UPD:
1951     case ARM::VLD1d64Q_UPD:
1952     case ARM::VLD2d8_UPD:
1953     case ARM::VLD2d16_UPD:
1954     case ARM::VLD2d32_UPD:
1955     case ARM::VLD2q8_UPD:
1956     case ARM::VLD2q16_UPD:
1957     case ARM::VLD2q32_UPD:
1958     case ARM::VLD2b8_UPD:
1959     case ARM::VLD2b16_UPD:
1960     case ARM::VLD2b32_UPD:
1961     case ARM::VLD3d8_UPD:
1962     case ARM::VLD3d16_UPD:
1963     case ARM::VLD3d32_UPD:
1964     case ARM::VLD3q8_UPD:
1965     case ARM::VLD3q16_UPD:
1966     case ARM::VLD3q32_UPD:
1967     case ARM::VLD4d8_UPD:
1968     case ARM::VLD4d16_UPD:
1969     case ARM::VLD4d32_UPD:
1970     case ARM::VLD4q8_UPD:
1971     case ARM::VLD4q16_UPD:
1972     case ARM::VLD4q32_UPD:
1973       if (!Check(S, DecodeGPRRegisterClass(Inst, wb, Address, Decoder)))
1974         return MCDisassembler::Fail;
1975       break;
1976     default:
1977       break;
1978   }
1979 
1980   // AddrMode6 Base (register+alignment)
1981   if (!Check(S, DecodeAddrMode6Operand(Inst, Rn, Address, Decoder)))
1982     return MCDisassembler::Fail;
1983 
1984   // AddrMode6 Offset (register)
1985   if (Rm == 0xD)
1986     Inst.addOperand(MCOperand::CreateReg(0));
1987   else if (Rm != 0xF) {
1988     if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
1989       return MCDisassembler::Fail;
1990   }
1991 
1992   return S;
1993 }
1994 
1995 static DecodeStatus DecodeVSTInstruction(llvm::MCInst &Inst, unsigned Insn,
1996                                  uint64_t Address, const void *Decoder) {
1997   DecodeStatus S = MCDisassembler::Success;
1998 
1999   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
2000   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
2001   unsigned wb = fieldFromInstruction32(Insn, 16, 4);
2002   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
2003   Rn |= fieldFromInstruction32(Insn, 4, 2) << 4;
2004   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
2005 
2006   // Writeback Operand
2007   switch (Inst.getOpcode()) {
2008     case ARM::VST1d8_UPD:
2009     case ARM::VST1d16_UPD:
2010     case ARM::VST1d32_UPD:
2011     case ARM::VST1d64_UPD:
2012     case ARM::VST1q8_UPD:
2013     case ARM::VST1q16_UPD:
2014     case ARM::VST1q32_UPD:
2015     case ARM::VST1q64_UPD:
2016     case ARM::VST1d8T_UPD:
2017     case ARM::VST1d16T_UPD:
2018     case ARM::VST1d32T_UPD:
2019     case ARM::VST1d64T_UPD:
2020     case ARM::VST1d8Q_UPD:
2021     case ARM::VST1d16Q_UPD:
2022     case ARM::VST1d32Q_UPD:
2023     case ARM::VST1d64Q_UPD:
2024     case ARM::VST2d8_UPD:
2025     case ARM::VST2d16_UPD:
2026     case ARM::VST2d32_UPD:
2027     case ARM::VST2q8_UPD:
2028     case ARM::VST2q16_UPD:
2029     case ARM::VST2q32_UPD:
2030     case ARM::VST2b8_UPD:
2031     case ARM::VST2b16_UPD:
2032     case ARM::VST2b32_UPD:
2033     case ARM::VST3d8_UPD:
2034     case ARM::VST3d16_UPD:
2035     case ARM::VST3d32_UPD:
2036     case ARM::VST3q8_UPD:
2037     case ARM::VST3q16_UPD:
2038     case ARM::VST3q32_UPD:
2039     case ARM::VST4d8_UPD:
2040     case ARM::VST4d16_UPD:
2041     case ARM::VST4d32_UPD:
2042     case ARM::VST4q8_UPD:
2043     case ARM::VST4q16_UPD:
2044     case ARM::VST4q32_UPD:
2045       if (!Check(S, DecodeGPRRegisterClass(Inst, wb, Address, Decoder)))
2046         return MCDisassembler::Fail;
2047       break;
2048     default:
2049       break;
2050   }
2051 
2052   // AddrMode6 Base (register+alignment)
2053   if (!Check(S, DecodeAddrMode6Operand(Inst, Rn, Address, Decoder)))
2054     return MCDisassembler::Fail;
2055 
2056   // AddrMode6 Offset (register)
2057   if (Rm == 0xD)
2058     Inst.addOperand(MCOperand::CreateReg(0));
2059   else if (Rm != 0xF) {
2060     if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
2061     return MCDisassembler::Fail;
2062   }
2063 
2064   // First input register
2065   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
2066     return MCDisassembler::Fail;
2067 
2068   // Second input register
2069   switch (Inst.getOpcode()) {
2070     case ARM::VST1q8:
2071     case ARM::VST1q16:
2072     case ARM::VST1q32:
2073     case ARM::VST1q64:
2074     case ARM::VST1q8_UPD:
2075     case ARM::VST1q16_UPD:
2076     case ARM::VST1q32_UPD:
2077     case ARM::VST1q64_UPD:
2078     case ARM::VST1d8T:
2079     case ARM::VST1d16T:
2080     case ARM::VST1d32T:
2081     case ARM::VST1d64T:
2082     case ARM::VST1d8T_UPD:
2083     case ARM::VST1d16T_UPD:
2084     case ARM::VST1d32T_UPD:
2085     case ARM::VST1d64T_UPD:
2086     case ARM::VST1d8Q:
2087     case ARM::VST1d16Q:
2088     case ARM::VST1d32Q:
2089     case ARM::VST1d64Q:
2090     case ARM::VST1d8Q_UPD:
2091     case ARM::VST1d16Q_UPD:
2092     case ARM::VST1d32Q_UPD:
2093     case ARM::VST1d64Q_UPD:
2094     case ARM::VST2d8:
2095     case ARM::VST2d16:
2096     case ARM::VST2d32:
2097     case ARM::VST2d8_UPD:
2098     case ARM::VST2d16_UPD:
2099     case ARM::VST2d32_UPD:
2100     case ARM::VST2q8:
2101     case ARM::VST2q16:
2102     case ARM::VST2q32:
2103     case ARM::VST2q8_UPD:
2104     case ARM::VST2q16_UPD:
2105     case ARM::VST2q32_UPD:
2106     case ARM::VST3d8:
2107     case ARM::VST3d16:
2108     case ARM::VST3d32:
2109     case ARM::VST3d8_UPD:
2110     case ARM::VST3d16_UPD:
2111     case ARM::VST3d32_UPD:
2112     case ARM::VST4d8:
2113     case ARM::VST4d16:
2114     case ARM::VST4d32:
2115     case ARM::VST4d8_UPD:
2116     case ARM::VST4d16_UPD:
2117     case ARM::VST4d32_UPD:
2118       if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+1)%32, Address, Decoder)))
2119         return MCDisassembler::Fail;
2120       break;
2121     case ARM::VST2b8:
2122     case ARM::VST2b16:
2123     case ARM::VST2b32:
2124     case ARM::VST2b8_UPD:
2125     case ARM::VST2b16_UPD:
2126     case ARM::VST2b32_UPD:
2127     case ARM::VST3q8:
2128     case ARM::VST3q16:
2129     case ARM::VST3q32:
2130     case ARM::VST3q8_UPD:
2131     case ARM::VST3q16_UPD:
2132     case ARM::VST3q32_UPD:
2133     case ARM::VST4q8:
2134     case ARM::VST4q16:
2135     case ARM::VST4q32:
2136     case ARM::VST4q8_UPD:
2137     case ARM::VST4q16_UPD:
2138     case ARM::VST4q32_UPD:
2139       if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+2)%32, Address, Decoder)))
2140         return MCDisassembler::Fail;
2141       break;
2142     default:
2143       break;
2144   }
2145 
2146   // Third input register
2147   switch (Inst.getOpcode()) {
2148     case ARM::VST1d8T:
2149     case ARM::VST1d16T:
2150     case ARM::VST1d32T:
2151     case ARM::VST1d64T:
2152     case ARM::VST1d8T_UPD:
2153     case ARM::VST1d16T_UPD:
2154     case ARM::VST1d32T_UPD:
2155     case ARM::VST1d64T_UPD:
2156     case ARM::VST1d8Q:
2157     case ARM::VST1d16Q:
2158     case ARM::VST1d32Q:
2159     case ARM::VST1d64Q:
2160     case ARM::VST1d8Q_UPD:
2161     case ARM::VST1d16Q_UPD:
2162     case ARM::VST1d32Q_UPD:
2163     case ARM::VST1d64Q_UPD:
2164     case ARM::VST2q8:
2165     case ARM::VST2q16:
2166     case ARM::VST2q32:
2167     case ARM::VST2q8_UPD:
2168     case ARM::VST2q16_UPD:
2169     case ARM::VST2q32_UPD:
2170     case ARM::VST3d8:
2171     case ARM::VST3d16:
2172     case ARM::VST3d32:
2173     case ARM::VST3d8_UPD:
2174     case ARM::VST3d16_UPD:
2175     case ARM::VST3d32_UPD:
2176     case ARM::VST4d8:
2177     case ARM::VST4d16:
2178     case ARM::VST4d32:
2179     case ARM::VST4d8_UPD:
2180     case ARM::VST4d16_UPD:
2181     case ARM::VST4d32_UPD:
2182       if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+2)%32, Address, Decoder)))
2183         return MCDisassembler::Fail;
2184       break;
2185     case ARM::VST3q8:
2186     case ARM::VST3q16:
2187     case ARM::VST3q32:
2188     case ARM::VST3q8_UPD:
2189     case ARM::VST3q16_UPD:
2190     case ARM::VST3q32_UPD:
2191     case ARM::VST4q8:
2192     case ARM::VST4q16:
2193     case ARM::VST4q32:
2194     case ARM::VST4q8_UPD:
2195     case ARM::VST4q16_UPD:
2196     case ARM::VST4q32_UPD:
2197       if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+4)%32, Address, Decoder)))
2198         return MCDisassembler::Fail;
2199       break;
2200     default:
2201       break;
2202   }
2203 
2204   // Fourth input register
2205   switch (Inst.getOpcode()) {
2206     case ARM::VST1d8Q:
2207     case ARM::VST1d16Q:
2208     case ARM::VST1d32Q:
2209     case ARM::VST1d64Q:
2210     case ARM::VST1d8Q_UPD:
2211     case ARM::VST1d16Q_UPD:
2212     case ARM::VST1d32Q_UPD:
2213     case ARM::VST1d64Q_UPD:
2214     case ARM::VST2q8:
2215     case ARM::VST2q16:
2216     case ARM::VST2q32:
2217     case ARM::VST2q8_UPD:
2218     case ARM::VST2q16_UPD:
2219     case ARM::VST2q32_UPD:
2220     case ARM::VST4d8:
2221     case ARM::VST4d16:
2222     case ARM::VST4d32:
2223     case ARM::VST4d8_UPD:
2224     case ARM::VST4d16_UPD:
2225     case ARM::VST4d32_UPD:
2226       if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+3)%32, Address, Decoder)))
2227         return MCDisassembler::Fail;
2228       break;
2229     case ARM::VST4q8:
2230     case ARM::VST4q16:
2231     case ARM::VST4q32:
2232     case ARM::VST4q8_UPD:
2233     case ARM::VST4q16_UPD:
2234     case ARM::VST4q32_UPD:
2235       if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+6)%32, Address, Decoder)))
2236         return MCDisassembler::Fail;
2237       break;
2238     default:
2239       break;
2240   }
2241 
2242   return S;
2243 }
2244 
2245 static DecodeStatus DecodeVLD1DupInstruction(llvm::MCInst &Inst, unsigned Insn,
2246                                     uint64_t Address, const void *Decoder) {
2247   DecodeStatus S = MCDisassembler::Success;
2248 
2249   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
2250   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
2251   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
2252   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
2253   unsigned align = fieldFromInstruction32(Insn, 4, 1);
2254   unsigned size = fieldFromInstruction32(Insn, 6, 2);
2255   unsigned regs = fieldFromInstruction32(Insn, 5, 1) + 1;
2256 
2257   align *= (1 << size);
2258 
2259   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
2260     return MCDisassembler::Fail;
2261   if (regs == 2) {
2262     if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+1)%32, Address, Decoder)))
2263       return MCDisassembler::Fail;
2264   }
2265   if (Rm != 0xF) {
2266     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2267       return MCDisassembler::Fail;
2268   }
2269 
2270   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2271     return MCDisassembler::Fail;
2272   Inst.addOperand(MCOperand::CreateImm(align));
2273 
2274   if (Rm == 0xD)
2275     Inst.addOperand(MCOperand::CreateReg(0));
2276   else if (Rm != 0xF) {
2277     if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
2278       return MCDisassembler::Fail;
2279   }
2280 
2281   return S;
2282 }
2283 
2284 static DecodeStatus DecodeVLD2DupInstruction(llvm::MCInst &Inst, unsigned Insn,
2285                                     uint64_t Address, const void *Decoder) {
2286   DecodeStatus S = MCDisassembler::Success;
2287 
2288   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
2289   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
2290   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
2291   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
2292   unsigned align = fieldFromInstruction32(Insn, 4, 1);
2293   unsigned size = 1 << fieldFromInstruction32(Insn, 6, 2);
2294   unsigned inc = fieldFromInstruction32(Insn, 5, 1) + 1;
2295   align *= 2*size;
2296 
2297   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
2298     return MCDisassembler::Fail;
2299   if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+inc)%32, Address, Decoder)))
2300     return MCDisassembler::Fail;
2301   if (Rm != 0xF) {
2302     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2303       return MCDisassembler::Fail;
2304   }
2305 
2306   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2307     return MCDisassembler::Fail;
2308   Inst.addOperand(MCOperand::CreateImm(align));
2309 
2310   if (Rm == 0xD)
2311     Inst.addOperand(MCOperand::CreateReg(0));
2312   else if (Rm != 0xF) {
2313     if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
2314       return MCDisassembler::Fail;
2315   }
2316 
2317   return S;
2318 }
2319 
2320 static DecodeStatus DecodeVLD3DupInstruction(llvm::MCInst &Inst, unsigned Insn,
2321                                     uint64_t Address, const void *Decoder) {
2322   DecodeStatus S = MCDisassembler::Success;
2323 
2324   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
2325   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
2326   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
2327   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
2328   unsigned inc = fieldFromInstruction32(Insn, 5, 1) + 1;
2329 
2330   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
2331     return MCDisassembler::Fail;
2332   if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+inc)%32, Address, Decoder)))
2333     return MCDisassembler::Fail;
2334   if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+2*inc)%32, Address, Decoder)))
2335     return MCDisassembler::Fail;
2336   if (Rm != 0xF) {
2337     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2338       return MCDisassembler::Fail;
2339   }
2340 
2341   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2342     return MCDisassembler::Fail;
2343   Inst.addOperand(MCOperand::CreateImm(0));
2344 
2345   if (Rm == 0xD)
2346     Inst.addOperand(MCOperand::CreateReg(0));
2347   else if (Rm != 0xF) {
2348     if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
2349       return MCDisassembler::Fail;
2350   }
2351 
2352   return S;
2353 }
2354 
2355 static DecodeStatus DecodeVLD4DupInstruction(llvm::MCInst &Inst, unsigned Insn,
2356                                     uint64_t Address, const void *Decoder) {
2357   DecodeStatus S = MCDisassembler::Success;
2358 
2359   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
2360   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
2361   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
2362   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
2363   unsigned size = fieldFromInstruction32(Insn, 6, 2);
2364   unsigned inc = fieldFromInstruction32(Insn, 5, 1) + 1;
2365   unsigned align = fieldFromInstruction32(Insn, 4, 1);
2366 
2367   if (size == 0x3) {
2368     size = 4;
2369     align = 16;
2370   } else {
2371     if (size == 2) {
2372       size = 1 << size;
2373       align *= 8;
2374     } else {
2375       size = 1 << size;
2376       align *= 4*size;
2377     }
2378   }
2379 
2380   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
2381     return MCDisassembler::Fail;
2382   if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+inc)%32, Address, Decoder)))
2383     return MCDisassembler::Fail;
2384   if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+2*inc)%32, Address, Decoder)))
2385     return MCDisassembler::Fail;
2386   if (!Check(S, DecodeDPRRegisterClass(Inst, (Rd+3*inc)%32, Address, Decoder)))
2387     return MCDisassembler::Fail;
2388   if (Rm != 0xF) {
2389     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2390       return MCDisassembler::Fail;
2391   }
2392 
2393   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2394     return MCDisassembler::Fail;
2395   Inst.addOperand(MCOperand::CreateImm(align));
2396 
2397   if (Rm == 0xD)
2398     Inst.addOperand(MCOperand::CreateReg(0));
2399   else if (Rm != 0xF) {
2400     if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
2401       return MCDisassembler::Fail;
2402   }
2403 
2404   return S;
2405 }
2406 
2407 static DecodeStatus
2408 DecodeNEONModImmInstruction(llvm::MCInst &Inst, unsigned Insn,
2409                             uint64_t Address, const void *Decoder) {
2410   DecodeStatus S = MCDisassembler::Success;
2411 
2412   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
2413   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
2414   unsigned imm = fieldFromInstruction32(Insn, 0, 4);
2415   imm |= fieldFromInstruction32(Insn, 16, 3) << 4;
2416   imm |= fieldFromInstruction32(Insn, 24, 1) << 7;
2417   imm |= fieldFromInstruction32(Insn, 8, 4) << 8;
2418   imm |= fieldFromInstruction32(Insn, 5, 1) << 12;
2419   unsigned Q = fieldFromInstruction32(Insn, 6, 1);
2420 
2421   if (Q) {
2422     if (!Check(S, DecodeQPRRegisterClass(Inst, Rd, Address, Decoder)))
2423     return MCDisassembler::Fail;
2424   } else {
2425     if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
2426     return MCDisassembler::Fail;
2427   }
2428 
2429   Inst.addOperand(MCOperand::CreateImm(imm));
2430 
2431   switch (Inst.getOpcode()) {
2432     case ARM::VORRiv4i16:
2433     case ARM::VORRiv2i32:
2434     case ARM::VBICiv4i16:
2435     case ARM::VBICiv2i32:
2436       if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
2437         return MCDisassembler::Fail;
2438       break;
2439     case ARM::VORRiv8i16:
2440     case ARM::VORRiv4i32:
2441     case ARM::VBICiv8i16:
2442     case ARM::VBICiv4i32:
2443       if (!Check(S, DecodeQPRRegisterClass(Inst, Rd, Address, Decoder)))
2444         return MCDisassembler::Fail;
2445       break;
2446     default:
2447       break;
2448   }
2449 
2450   return S;
2451 }
2452 
2453 static DecodeStatus DecodeVSHLMaxInstruction(llvm::MCInst &Inst, unsigned Insn,
2454                                         uint64_t Address, const void *Decoder) {
2455   DecodeStatus S = MCDisassembler::Success;
2456 
2457   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
2458   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
2459   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
2460   Rm |= fieldFromInstruction32(Insn, 5, 1) << 4;
2461   unsigned size = fieldFromInstruction32(Insn, 18, 2);
2462 
2463   if (!Check(S, DecodeQPRRegisterClass(Inst, Rd, Address, Decoder)))
2464     return MCDisassembler::Fail;
2465   if (!Check(S, DecodeDPRRegisterClass(Inst, Rm, Address, Decoder)))
2466     return MCDisassembler::Fail;
2467   Inst.addOperand(MCOperand::CreateImm(8 << size));
2468 
2469   return S;
2470 }
2471 
2472 static DecodeStatus DecodeShiftRight8Imm(llvm::MCInst &Inst, unsigned Val,
2473                                uint64_t Address, const void *Decoder) {
2474   Inst.addOperand(MCOperand::CreateImm(8 - Val));
2475   return MCDisassembler::Success;
2476 }
2477 
2478 static DecodeStatus DecodeShiftRight16Imm(llvm::MCInst &Inst, unsigned Val,
2479                                uint64_t Address, const void *Decoder) {
2480   Inst.addOperand(MCOperand::CreateImm(16 - Val));
2481   return MCDisassembler::Success;
2482 }
2483 
2484 static DecodeStatus DecodeShiftRight32Imm(llvm::MCInst &Inst, unsigned Val,
2485                                uint64_t Address, const void *Decoder) {
2486   Inst.addOperand(MCOperand::CreateImm(32 - Val));
2487   return MCDisassembler::Success;
2488 }
2489 
2490 static DecodeStatus DecodeShiftRight64Imm(llvm::MCInst &Inst, unsigned Val,
2491                                uint64_t Address, const void *Decoder) {
2492   Inst.addOperand(MCOperand::CreateImm(64 - Val));
2493   return MCDisassembler::Success;
2494 }
2495 
2496 static DecodeStatus DecodeTBLInstruction(llvm::MCInst &Inst, unsigned Insn,
2497                                uint64_t Address, const void *Decoder) {
2498   DecodeStatus S = MCDisassembler::Success;
2499 
2500   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
2501   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
2502   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
2503   Rn |= fieldFromInstruction32(Insn, 7, 1) << 4;
2504   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
2505   Rm |= fieldFromInstruction32(Insn, 5, 1) << 4;
2506   unsigned op = fieldFromInstruction32(Insn, 6, 1);
2507   unsigned length = fieldFromInstruction32(Insn, 8, 2) + 1;
2508 
2509   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
2510     return MCDisassembler::Fail;
2511   if (op) {
2512     if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
2513     return MCDisassembler::Fail; // Writeback
2514   }
2515 
2516   for (unsigned i = 0; i < length; ++i) {
2517     if (!Check(S, DecodeDPRRegisterClass(Inst, (Rn+i)%32, Address, Decoder)))
2518     return MCDisassembler::Fail;
2519   }
2520 
2521   if (!Check(S, DecodeDPRRegisterClass(Inst, Rm, Address, Decoder)))
2522     return MCDisassembler::Fail;
2523 
2524   return S;
2525 }
2526 
2527 static DecodeStatus DecodeVFPfpImm(llvm::MCInst &Inst, unsigned Val,
2528                             uint64_t Address, const void *Decoder) {
2529   // The immediate needs to be a fully instantiated float.  However, the
2530   // auto-generated decoder is only able to fill in some of the bits
2531   // necessary.  For instance, the 'b' bit is replicated multiple times,
2532   // and is even present in inverted form in one bit.  We do a little
2533   // binary parsing here to fill in those missing bits, and then
2534   // reinterpret it all as a float.
2535   union {
2536     uint32_t integer;
2537     float fp;
2538   } fp_conv;
2539 
2540   fp_conv.integer = Val;
2541   uint32_t b = fieldFromInstruction32(Val, 25, 1);
2542   fp_conv.integer |= b << 26;
2543   fp_conv.integer |= b << 27;
2544   fp_conv.integer |= b << 28;
2545   fp_conv.integer |= b << 29;
2546   fp_conv.integer |= (~b & 0x1) << 30;
2547 
2548   Inst.addOperand(MCOperand::CreateFPImm(fp_conv.fp));
2549   return MCDisassembler::Success;
2550 }
2551 
2552 static DecodeStatus DecodeThumbAddSpecialReg(llvm::MCInst &Inst, uint16_t Insn,
2553                                      uint64_t Address, const void *Decoder) {
2554   DecodeStatus S = MCDisassembler::Success;
2555 
2556   unsigned dst = fieldFromInstruction16(Insn, 8, 3);
2557   unsigned imm = fieldFromInstruction16(Insn, 0, 8);
2558 
2559   if (!Check(S, DecodetGPRRegisterClass(Inst, dst, Address, Decoder)))
2560     return MCDisassembler::Fail;
2561 
2562   switch(Inst.getOpcode()) {
2563     default:
2564       return MCDisassembler::Fail;
2565     case ARM::tADR:
2566       break; // tADR does not explicitly represent the PC as an operand.
2567     case ARM::tADDrSPi:
2568       Inst.addOperand(MCOperand::CreateReg(ARM::SP));
2569       break;
2570   }
2571 
2572   Inst.addOperand(MCOperand::CreateImm(imm));
2573   return S;
2574 }
2575 
2576 static DecodeStatus DecodeThumbBROperand(llvm::MCInst &Inst, unsigned Val,
2577                                  uint64_t Address, const void *Decoder) {
2578   Inst.addOperand(MCOperand::CreateImm(SignExtend32<12>(Val << 1)));
2579   return MCDisassembler::Success;
2580 }
2581 
2582 static DecodeStatus DecodeT2BROperand(llvm::MCInst &Inst, unsigned Val,
2583                                  uint64_t Address, const void *Decoder) {
2584   Inst.addOperand(MCOperand::CreateImm(SignExtend32<21>(Val)));
2585   return MCDisassembler::Success;
2586 }
2587 
2588 static DecodeStatus DecodeThumbCmpBROperand(llvm::MCInst &Inst, unsigned Val,
2589                                  uint64_t Address, const void *Decoder) {
2590   Inst.addOperand(MCOperand::CreateImm(SignExtend32<7>(Val << 1)));
2591   return MCDisassembler::Success;
2592 }
2593 
2594 static DecodeStatus DecodeThumbAddrModeRR(llvm::MCInst &Inst, unsigned Val,
2595                                  uint64_t Address, const void *Decoder) {
2596   DecodeStatus S = MCDisassembler::Success;
2597 
2598   unsigned Rn = fieldFromInstruction32(Val, 0, 3);
2599   unsigned Rm = fieldFromInstruction32(Val, 3, 3);
2600 
2601   if (!Check(S, DecodetGPRRegisterClass(Inst, Rn, Address, Decoder)))
2602     return MCDisassembler::Fail;
2603   if (!Check(S, DecodetGPRRegisterClass(Inst, Rm, Address, Decoder)))
2604     return MCDisassembler::Fail;
2605 
2606   return S;
2607 }
2608 
2609 static DecodeStatus DecodeThumbAddrModeIS(llvm::MCInst &Inst, unsigned Val,
2610                                   uint64_t Address, const void *Decoder) {
2611   DecodeStatus S = MCDisassembler::Success;
2612 
2613   unsigned Rn = fieldFromInstruction32(Val, 0, 3);
2614   unsigned imm = fieldFromInstruction32(Val, 3, 5);
2615 
2616   if (!Check(S, DecodetGPRRegisterClass(Inst, Rn, Address, Decoder)))
2617     return MCDisassembler::Fail;
2618   Inst.addOperand(MCOperand::CreateImm(imm));
2619 
2620   return S;
2621 }
2622 
2623 static DecodeStatus DecodeThumbAddrModePC(llvm::MCInst &Inst, unsigned Val,
2624                                   uint64_t Address, const void *Decoder) {
2625   Inst.addOperand(MCOperand::CreateImm(Val << 2));
2626 
2627   return MCDisassembler::Success;
2628 }
2629 
2630 static DecodeStatus DecodeThumbAddrModeSP(llvm::MCInst &Inst, unsigned Val,
2631                                   uint64_t Address, const void *Decoder) {
2632   Inst.addOperand(MCOperand::CreateReg(ARM::SP));
2633   Inst.addOperand(MCOperand::CreateImm(Val));
2634 
2635   return MCDisassembler::Success;
2636 }
2637 
2638 static DecodeStatus DecodeT2AddrModeSOReg(llvm::MCInst &Inst, unsigned Val,
2639                                   uint64_t Address, const void *Decoder) {
2640   DecodeStatus S = MCDisassembler::Success;
2641 
2642   unsigned Rn = fieldFromInstruction32(Val, 6, 4);
2643   unsigned Rm = fieldFromInstruction32(Val, 2, 4);
2644   unsigned imm = fieldFromInstruction32(Val, 0, 2);
2645 
2646   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2647     return MCDisassembler::Fail;
2648   if (!Check(S, DecoderGPRRegisterClass(Inst, Rm, Address, Decoder)))
2649     return MCDisassembler::Fail;
2650   Inst.addOperand(MCOperand::CreateImm(imm));
2651 
2652   return S;
2653 }
2654 
2655 static DecodeStatus DecodeT2LoadShift(llvm::MCInst &Inst, unsigned Insn,
2656                               uint64_t Address, const void *Decoder) {
2657   DecodeStatus S = MCDisassembler::Success;
2658 
2659   switch (Inst.getOpcode()) {
2660     case ARM::t2PLDs:
2661     case ARM::t2PLDWs:
2662     case ARM::t2PLIs:
2663       break;
2664     default: {
2665       unsigned Rt = fieldFromInstruction32(Insn, 12, 4);
2666       if (!Check(S, DecoderGPRRegisterClass(Inst, Rt, Address, Decoder)))
2667     return MCDisassembler::Fail;
2668     }
2669   }
2670 
2671   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
2672   if (Rn == 0xF) {
2673     switch (Inst.getOpcode()) {
2674       case ARM::t2LDRBs:
2675         Inst.setOpcode(ARM::t2LDRBpci);
2676         break;
2677       case ARM::t2LDRHs:
2678         Inst.setOpcode(ARM::t2LDRHpci);
2679         break;
2680       case ARM::t2LDRSHs:
2681         Inst.setOpcode(ARM::t2LDRSHpci);
2682         break;
2683       case ARM::t2LDRSBs:
2684         Inst.setOpcode(ARM::t2LDRSBpci);
2685         break;
2686       case ARM::t2PLDs:
2687         Inst.setOpcode(ARM::t2PLDi12);
2688         Inst.addOperand(MCOperand::CreateReg(ARM::PC));
2689         break;
2690       default:
2691         return MCDisassembler::Fail;
2692     }
2693 
2694     int imm = fieldFromInstruction32(Insn, 0, 12);
2695     if (!fieldFromInstruction32(Insn, 23, 1)) imm *= -1;
2696     Inst.addOperand(MCOperand::CreateImm(imm));
2697 
2698     return S;
2699   }
2700 
2701   unsigned addrmode = fieldFromInstruction32(Insn, 4, 2);
2702   addrmode |= fieldFromInstruction32(Insn, 0, 4) << 2;
2703   addrmode |= fieldFromInstruction32(Insn, 16, 4) << 6;
2704   if (!Check(S, DecodeT2AddrModeSOReg(Inst, addrmode, Address, Decoder)))
2705     return MCDisassembler::Fail;
2706 
2707   return S;
2708 }
2709 
2710 static DecodeStatus DecodeT2Imm8S4(llvm::MCInst &Inst, unsigned Val,
2711                            uint64_t Address, const void *Decoder) {
2712   int imm = Val & 0xFF;
2713   if (!(Val & 0x100)) imm *= -1;
2714   Inst.addOperand(MCOperand::CreateImm(imm << 2));
2715 
2716   return MCDisassembler::Success;
2717 }
2718 
2719 static DecodeStatus DecodeT2AddrModeImm8s4(llvm::MCInst &Inst, unsigned Val,
2720                                    uint64_t Address, const void *Decoder) {
2721   DecodeStatus S = MCDisassembler::Success;
2722 
2723   unsigned Rn = fieldFromInstruction32(Val, 9, 4);
2724   unsigned imm = fieldFromInstruction32(Val, 0, 9);
2725 
2726   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2727     return MCDisassembler::Fail;
2728   if (!Check(S, DecodeT2Imm8S4(Inst, imm, Address, Decoder)))
2729     return MCDisassembler::Fail;
2730 
2731   return S;
2732 }
2733 
2734 static DecodeStatus DecodeT2AddrModeImm0_1020s4(llvm::MCInst &Inst,unsigned Val,
2735                                    uint64_t Address, const void *Decoder) {
2736   DecodeStatus S = MCDisassembler::Success;
2737 
2738   unsigned Rn = fieldFromInstruction32(Val, 8, 4);
2739   unsigned imm = fieldFromInstruction32(Val, 0, 8);
2740 
2741   if (!Check(S, DecodeGPRnopcRegisterClass(Inst, Rn, Address, Decoder)))
2742     return MCDisassembler::Fail;
2743 
2744   Inst.addOperand(MCOperand::CreateImm(imm));
2745 
2746   return S;
2747 }
2748 
2749 static DecodeStatus DecodeT2Imm8(llvm::MCInst &Inst, unsigned Val,
2750                          uint64_t Address, const void *Decoder) {
2751   int imm = Val & 0xFF;
2752   if (Val == 0)
2753     imm = INT32_MIN;
2754   else if (!(Val & 0x100))
2755     imm *= -1;
2756   Inst.addOperand(MCOperand::CreateImm(imm));
2757 
2758   return MCDisassembler::Success;
2759 }
2760 
2761 
2762 static DecodeStatus DecodeT2AddrModeImm8(llvm::MCInst &Inst, unsigned Val,
2763                                  uint64_t Address, const void *Decoder) {
2764   DecodeStatus S = MCDisassembler::Success;
2765 
2766   unsigned Rn = fieldFromInstruction32(Val, 9, 4);
2767   unsigned imm = fieldFromInstruction32(Val, 0, 9);
2768 
2769   // Some instructions always use an additive offset.
2770   switch (Inst.getOpcode()) {
2771     case ARM::t2LDRT:
2772     case ARM::t2LDRBT:
2773     case ARM::t2LDRHT:
2774     case ARM::t2LDRSBT:
2775     case ARM::t2LDRSHT:
2776     case ARM::t2STRT:
2777     case ARM::t2STRBT:
2778     case ARM::t2STRHT:
2779       imm |= 0x100;
2780       break;
2781     default:
2782       break;
2783   }
2784 
2785   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2786     return MCDisassembler::Fail;
2787   if (!Check(S, DecodeT2Imm8(Inst, imm, Address, Decoder)))
2788     return MCDisassembler::Fail;
2789 
2790   return S;
2791 }
2792 
2793 static DecodeStatus DecodeT2LdStPre(llvm::MCInst &Inst, unsigned Insn,
2794                                     uint64_t Address, const void *Decoder) {
2795   DecodeStatus S = MCDisassembler::Success;
2796 
2797   unsigned Rt = fieldFromInstruction32(Insn, 12, 4);
2798   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
2799   unsigned addr = fieldFromInstruction32(Insn, 0, 8);
2800   addr |= fieldFromInstruction32(Insn, 9, 1) << 8;
2801   addr |= Rn << 9;
2802   unsigned load = fieldFromInstruction32(Insn, 20, 1);
2803 
2804   if (!load) {
2805     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2806       return MCDisassembler::Fail;
2807   }
2808 
2809   if (!Check(S, DecoderGPRRegisterClass(Inst, Rt, Address, Decoder)))
2810     return MCDisassembler::Fail;
2811 
2812   if (load) {
2813     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2814       return MCDisassembler::Fail;
2815   }
2816 
2817   if (!Check(S, DecodeT2AddrModeImm8(Inst, addr, Address, Decoder)))
2818     return MCDisassembler::Fail;
2819 
2820   return S;
2821 }
2822 
2823 static DecodeStatus DecodeT2AddrModeImm12(llvm::MCInst &Inst, unsigned Val,
2824                                   uint64_t Address, const void *Decoder) {
2825   DecodeStatus S = MCDisassembler::Success;
2826 
2827   unsigned Rn = fieldFromInstruction32(Val, 13, 4);
2828   unsigned imm = fieldFromInstruction32(Val, 0, 12);
2829 
2830   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2831     return MCDisassembler::Fail;
2832   Inst.addOperand(MCOperand::CreateImm(imm));
2833 
2834   return S;
2835 }
2836 
2837 
2838 static DecodeStatus DecodeThumbAddSPImm(llvm::MCInst &Inst, uint16_t Insn,
2839                                 uint64_t Address, const void *Decoder) {
2840   unsigned imm = fieldFromInstruction16(Insn, 0, 7);
2841 
2842   Inst.addOperand(MCOperand::CreateReg(ARM::SP));
2843   Inst.addOperand(MCOperand::CreateReg(ARM::SP));
2844   Inst.addOperand(MCOperand::CreateImm(imm));
2845 
2846   return MCDisassembler::Success;
2847 }
2848 
2849 static DecodeStatus DecodeThumbAddSPReg(llvm::MCInst &Inst, uint16_t Insn,
2850                                 uint64_t Address, const void *Decoder) {
2851   DecodeStatus S = MCDisassembler::Success;
2852 
2853   if (Inst.getOpcode() == ARM::tADDrSP) {
2854     unsigned Rdm = fieldFromInstruction16(Insn, 0, 3);
2855     Rdm |= fieldFromInstruction16(Insn, 7, 1) << 3;
2856 
2857     if (!Check(S, DecodeGPRRegisterClass(Inst, Rdm, Address, Decoder)))
2858     return MCDisassembler::Fail;
2859     if (!Check(S, DecodeGPRRegisterClass(Inst, Rdm, Address, Decoder)))
2860     return MCDisassembler::Fail;
2861     Inst.addOperand(MCOperand::CreateReg(ARM::SP));
2862   } else if (Inst.getOpcode() == ARM::tADDspr) {
2863     unsigned Rm = fieldFromInstruction16(Insn, 3, 4);
2864 
2865     Inst.addOperand(MCOperand::CreateReg(ARM::SP));
2866     Inst.addOperand(MCOperand::CreateReg(ARM::SP));
2867     if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
2868     return MCDisassembler::Fail;
2869   }
2870 
2871   return S;
2872 }
2873 
2874 static DecodeStatus DecodeThumbCPS(llvm::MCInst &Inst, uint16_t Insn,
2875                            uint64_t Address, const void *Decoder) {
2876   unsigned imod = fieldFromInstruction16(Insn, 4, 1) | 0x2;
2877   unsigned flags = fieldFromInstruction16(Insn, 0, 3);
2878 
2879   Inst.addOperand(MCOperand::CreateImm(imod));
2880   Inst.addOperand(MCOperand::CreateImm(flags));
2881 
2882   return MCDisassembler::Success;
2883 }
2884 
2885 static DecodeStatus DecodePostIdxReg(llvm::MCInst &Inst, unsigned Insn,
2886                              uint64_t Address, const void *Decoder) {
2887   DecodeStatus S = MCDisassembler::Success;
2888   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
2889   unsigned add = fieldFromInstruction32(Insn, 4, 1);
2890 
2891   if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
2892     return MCDisassembler::Fail;
2893   Inst.addOperand(MCOperand::CreateImm(add));
2894 
2895   return S;
2896 }
2897 
2898 static DecodeStatus DecodeThumbBLXOffset(llvm::MCInst &Inst, unsigned Val,
2899                                  uint64_t Address, const void *Decoder) {
2900   Inst.addOperand(MCOperand::CreateImm(SignExtend32<22>(Val << 1)));
2901   return MCDisassembler::Success;
2902 }
2903 
2904 static DecodeStatus DecodeCoprocessor(llvm::MCInst &Inst, unsigned Val,
2905                               uint64_t Address, const void *Decoder) {
2906   if (Val == 0xA || Val == 0xB)
2907     return MCDisassembler::Fail;
2908 
2909   Inst.addOperand(MCOperand::CreateImm(Val));
2910   return MCDisassembler::Success;
2911 }
2912 
2913 static DecodeStatus
2914 DecodeThumbTableBranch(llvm::MCInst &Inst, unsigned Insn,
2915                        uint64_t Address, const void *Decoder) {
2916   DecodeStatus S = MCDisassembler::Success;
2917 
2918   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
2919   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
2920 
2921   if (Rn == ARM::SP) S = MCDisassembler::SoftFail;
2922   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
2923     return MCDisassembler::Fail;
2924   if (!Check(S, DecoderGPRRegisterClass(Inst, Rm, Address, Decoder)))
2925     return MCDisassembler::Fail;
2926   return S;
2927 }
2928 
2929 static DecodeStatus
2930 DecodeThumb2BCCInstruction(llvm::MCInst &Inst, unsigned Insn,
2931                            uint64_t Address, const void *Decoder) {
2932   DecodeStatus S = MCDisassembler::Success;
2933 
2934   unsigned pred = fieldFromInstruction32(Insn, 22, 4);
2935   if (pred == 0xE || pred == 0xF) {
2936     unsigned opc = fieldFromInstruction32(Insn, 4, 28);
2937     switch (opc) {
2938       default:
2939         return MCDisassembler::Fail;
2940       case 0xf3bf8f4:
2941         Inst.setOpcode(ARM::t2DSB);
2942         break;
2943       case 0xf3bf8f5:
2944         Inst.setOpcode(ARM::t2DMB);
2945         break;
2946       case 0xf3bf8f6:
2947         Inst.setOpcode(ARM::t2ISB);
2948         break;
2949     }
2950 
2951     unsigned imm = fieldFromInstruction32(Insn, 0, 4);
2952     return DecodeMemBarrierOption(Inst, imm, Address, Decoder);
2953   }
2954 
2955   unsigned brtarget = fieldFromInstruction32(Insn, 0, 11) << 1;
2956   brtarget |= fieldFromInstruction32(Insn, 11, 1) << 19;
2957   brtarget |= fieldFromInstruction32(Insn, 13, 1) << 18;
2958   brtarget |= fieldFromInstruction32(Insn, 16, 6) << 12;
2959   brtarget |= fieldFromInstruction32(Insn, 26, 1) << 20;
2960 
2961   if (!Check(S, DecodeT2BROperand(Inst, brtarget, Address, Decoder)))
2962     return MCDisassembler::Fail;
2963   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
2964     return MCDisassembler::Fail;
2965 
2966   return S;
2967 }
2968 
2969 // Decode a shifted immediate operand.  These basically consist
2970 // of an 8-bit value, and a 4-bit directive that specifies either
2971 // a splat operation or a rotation.
2972 static DecodeStatus DecodeT2SOImm(llvm::MCInst &Inst, unsigned Val,
2973                           uint64_t Address, const void *Decoder) {
2974   unsigned ctrl = fieldFromInstruction32(Val, 10, 2);
2975   if (ctrl == 0) {
2976     unsigned byte = fieldFromInstruction32(Val, 8, 2);
2977     unsigned imm = fieldFromInstruction32(Val, 0, 8);
2978     switch (byte) {
2979       case 0:
2980         Inst.addOperand(MCOperand::CreateImm(imm));
2981         break;
2982       case 1:
2983         Inst.addOperand(MCOperand::CreateImm((imm << 16) | imm));
2984         break;
2985       case 2:
2986         Inst.addOperand(MCOperand::CreateImm((imm << 24) | (imm << 8)));
2987         break;
2988       case 3:
2989         Inst.addOperand(MCOperand::CreateImm((imm << 24) | (imm << 16) |
2990                                              (imm << 8)  |  imm));
2991         break;
2992     }
2993   } else {
2994     unsigned unrot = fieldFromInstruction32(Val, 0, 7) | 0x80;
2995     unsigned rot = fieldFromInstruction32(Val, 7, 5);
2996     unsigned imm = (unrot >> rot) | (unrot << ((32-rot)&31));
2997     Inst.addOperand(MCOperand::CreateImm(imm));
2998   }
2999 
3000   return MCDisassembler::Success;
3001 }
3002 
3003 static DecodeStatus
3004 DecodeThumbBCCTargetOperand(llvm::MCInst &Inst, unsigned Val,
3005                             uint64_t Address, const void *Decoder){
3006   Inst.addOperand(MCOperand::CreateImm(Val << 1));
3007   return MCDisassembler::Success;
3008 }
3009 
3010 static DecodeStatus DecodeThumbBLTargetOperand(llvm::MCInst &Inst, unsigned Val,
3011                                        uint64_t Address, const void *Decoder){
3012   Inst.addOperand(MCOperand::CreateImm(SignExtend32<22>(Val << 1)));
3013   return MCDisassembler::Success;
3014 }
3015 
3016 static DecodeStatus DecodeMemBarrierOption(llvm::MCInst &Inst, unsigned Val,
3017                                    uint64_t Address, const void *Decoder) {
3018   switch (Val) {
3019   default:
3020     return MCDisassembler::Fail;
3021   case 0xF: // SY
3022   case 0xE: // ST
3023   case 0xB: // ISH
3024   case 0xA: // ISHST
3025   case 0x7: // NSH
3026   case 0x6: // NSHST
3027   case 0x3: // OSH
3028   case 0x2: // OSHST
3029     break;
3030   }
3031 
3032   Inst.addOperand(MCOperand::CreateImm(Val));
3033   return MCDisassembler::Success;
3034 }
3035 
3036 static DecodeStatus DecodeMSRMask(llvm::MCInst &Inst, unsigned Val,
3037                           uint64_t Address, const void *Decoder) {
3038   if (!Val) return MCDisassembler::Fail;
3039   Inst.addOperand(MCOperand::CreateImm(Val));
3040   return MCDisassembler::Success;
3041 }
3042 
3043 static DecodeStatus DecodeDoubleRegLoad(llvm::MCInst &Inst, unsigned Insn,
3044                                         uint64_t Address, const void *Decoder) {
3045   DecodeStatus S = MCDisassembler::Success;
3046 
3047   unsigned Rt = fieldFromInstruction32(Insn, 12, 4);
3048   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3049   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
3050 
3051   if ((Rt & 1) || Rt == 0xE || Rn == 0xF) return MCDisassembler::Fail;
3052 
3053   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt, Address, Decoder)))
3054     return MCDisassembler::Fail;
3055   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt+1, Address, Decoder)))
3056     return MCDisassembler::Fail;
3057   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3058     return MCDisassembler::Fail;
3059   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
3060     return MCDisassembler::Fail;
3061 
3062   return S;
3063 }
3064 
3065 
3066 static DecodeStatus DecodeDoubleRegStore(llvm::MCInst &Inst, unsigned Insn,
3067                                          uint64_t Address, const void *Decoder){
3068   DecodeStatus S = MCDisassembler::Success;
3069 
3070   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
3071   unsigned Rt = fieldFromInstruction32(Insn, 0, 4);
3072   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3073   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
3074 
3075   if (!Check(S, DecoderGPRRegisterClass(Inst, Rd, Address, Decoder)))
3076     return MCDisassembler::Fail;
3077 
3078   if ((Rt & 1) || Rt == 0xE || Rn == 0xF) return MCDisassembler::Fail;
3079   if (Rd == Rn || Rd == Rt || Rd == Rt+1) return MCDisassembler::Fail;
3080 
3081   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt, Address, Decoder)))
3082     return MCDisassembler::Fail;
3083   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt+1, Address, Decoder)))
3084     return MCDisassembler::Fail;
3085   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3086     return MCDisassembler::Fail;
3087   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
3088     return MCDisassembler::Fail;
3089 
3090   return S;
3091 }
3092 
3093 static DecodeStatus DecodeLDRPreImm(llvm::MCInst &Inst, unsigned Insn,
3094                             uint64_t Address, const void *Decoder) {
3095   DecodeStatus S = MCDisassembler::Success;
3096 
3097   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3098   unsigned Rt = fieldFromInstruction32(Insn, 12, 4);
3099   unsigned imm = fieldFromInstruction32(Insn, 0, 12);
3100   imm |= fieldFromInstruction32(Insn, 16, 4) << 13;
3101   imm |= fieldFromInstruction32(Insn, 23, 1) << 12;
3102   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
3103 
3104   if (Rn == 0xF || Rn == Rt) S = MCDisassembler::SoftFail;
3105 
3106   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt, Address, Decoder)))
3107     return MCDisassembler::Fail;
3108   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3109     return MCDisassembler::Fail;
3110   if (!Check(S, DecodeAddrModeImm12Operand(Inst, imm, Address, Decoder)))
3111     return MCDisassembler::Fail;
3112   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
3113     return MCDisassembler::Fail;
3114 
3115   return S;
3116 }
3117 
3118 static DecodeStatus DecodeLDRPreReg(llvm::MCInst &Inst, unsigned Insn,
3119                             uint64_t Address, const void *Decoder) {
3120   DecodeStatus S = MCDisassembler::Success;
3121 
3122   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3123   unsigned Rt = fieldFromInstruction32(Insn, 12, 4);
3124   unsigned imm = fieldFromInstruction32(Insn, 0, 12);
3125   imm |= fieldFromInstruction32(Insn, 16, 4) << 13;
3126   imm |= fieldFromInstruction32(Insn, 23, 1) << 12;
3127   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
3128   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
3129 
3130   if (Rn == 0xF || Rn == Rt) S = MCDisassembler::SoftFail;
3131   if (Rm == 0xF) S = MCDisassembler::SoftFail;
3132 
3133   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt, Address, Decoder)))
3134     return MCDisassembler::Fail;
3135   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3136     return MCDisassembler::Fail;
3137   if (!Check(S, DecodeSORegMemOperand(Inst, imm, Address, Decoder)))
3138     return MCDisassembler::Fail;
3139   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
3140     return MCDisassembler::Fail;
3141 
3142   return S;
3143 }
3144 
3145 
3146 static DecodeStatus DecodeSTRPreImm(llvm::MCInst &Inst, unsigned Insn,
3147                             uint64_t Address, const void *Decoder) {
3148   DecodeStatus S = MCDisassembler::Success;
3149 
3150   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3151   unsigned Rt = fieldFromInstruction32(Insn, 12, 4);
3152   unsigned imm = fieldFromInstruction32(Insn, 0, 12);
3153   imm |= fieldFromInstruction32(Insn, 16, 4) << 13;
3154   imm |= fieldFromInstruction32(Insn, 23, 1) << 12;
3155   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
3156 
3157   if (Rn == 0xF || Rn == Rt) S = MCDisassembler::SoftFail;
3158 
3159   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3160     return MCDisassembler::Fail;
3161   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt, Address, Decoder)))
3162     return MCDisassembler::Fail;
3163   if (!Check(S, DecodeAddrModeImm12Operand(Inst, imm, Address, Decoder)))
3164     return MCDisassembler::Fail;
3165   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
3166     return MCDisassembler::Fail;
3167 
3168   return S;
3169 }
3170 
3171 static DecodeStatus DecodeSTRPreReg(llvm::MCInst &Inst, unsigned Insn,
3172                             uint64_t Address, const void *Decoder) {
3173   DecodeStatus S = MCDisassembler::Success;
3174 
3175   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3176   unsigned Rt = fieldFromInstruction32(Insn, 12, 4);
3177   unsigned imm = fieldFromInstruction32(Insn, 0, 12);
3178   imm |= fieldFromInstruction32(Insn, 16, 4) << 13;
3179   imm |= fieldFromInstruction32(Insn, 23, 1) << 12;
3180   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
3181 
3182   if (Rn == 0xF || Rn == Rt) S = MCDisassembler::SoftFail;
3183 
3184   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3185     return MCDisassembler::Fail;
3186   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt, Address, Decoder)))
3187     return MCDisassembler::Fail;
3188   if (!Check(S, DecodeSORegMemOperand(Inst, imm, Address, Decoder)))
3189     return MCDisassembler::Fail;
3190   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
3191     return MCDisassembler::Fail;
3192 
3193   return S;
3194 }
3195 
3196 static DecodeStatus DecodeVLD1LN(llvm::MCInst &Inst, unsigned Insn,
3197                          uint64_t Address, const void *Decoder) {
3198   DecodeStatus S = MCDisassembler::Success;
3199 
3200   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3201   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
3202   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
3203   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
3204   unsigned size = fieldFromInstruction32(Insn, 10, 2);
3205 
3206   unsigned align = 0;
3207   unsigned index = 0;
3208   switch (size) {
3209     default:
3210       return MCDisassembler::Fail;
3211     case 0:
3212       if (fieldFromInstruction32(Insn, 4, 1))
3213         return MCDisassembler::Fail; // UNDEFINED
3214       index = fieldFromInstruction32(Insn, 5, 3);
3215       break;
3216     case 1:
3217       if (fieldFromInstruction32(Insn, 5, 1))
3218         return MCDisassembler::Fail; // UNDEFINED
3219       index = fieldFromInstruction32(Insn, 6, 2);
3220       if (fieldFromInstruction32(Insn, 4, 1))
3221         align = 2;
3222       break;
3223     case 2:
3224       if (fieldFromInstruction32(Insn, 6, 1))
3225         return MCDisassembler::Fail; // UNDEFINED
3226       index = fieldFromInstruction32(Insn, 7, 1);
3227       if (fieldFromInstruction32(Insn, 4, 2) != 0)
3228         align = 4;
3229   }
3230 
3231   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
3232     return MCDisassembler::Fail;
3233   if (Rm != 0xF) { // Writeback
3234     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3235       return MCDisassembler::Fail;
3236   }
3237   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3238     return MCDisassembler::Fail;
3239   Inst.addOperand(MCOperand::CreateImm(align));
3240   if (Rm != 0xF) {
3241     if (Rm != 0xD) {
3242       if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
3243         return MCDisassembler::Fail;
3244     } else
3245       Inst.addOperand(MCOperand::CreateReg(0));
3246   }
3247 
3248   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
3249     return MCDisassembler::Fail;
3250   Inst.addOperand(MCOperand::CreateImm(index));
3251 
3252   return S;
3253 }
3254 
3255 static DecodeStatus DecodeVST1LN(llvm::MCInst &Inst, unsigned Insn,
3256                          uint64_t Address, const void *Decoder) {
3257   DecodeStatus S = MCDisassembler::Success;
3258 
3259   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3260   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
3261   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
3262   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
3263   unsigned size = fieldFromInstruction32(Insn, 10, 2);
3264 
3265   unsigned align = 0;
3266   unsigned index = 0;
3267   switch (size) {
3268     default:
3269       return MCDisassembler::Fail;
3270     case 0:
3271       if (fieldFromInstruction32(Insn, 4, 1))
3272         return MCDisassembler::Fail; // UNDEFINED
3273       index = fieldFromInstruction32(Insn, 5, 3);
3274       break;
3275     case 1:
3276       if (fieldFromInstruction32(Insn, 5, 1))
3277         return MCDisassembler::Fail; // UNDEFINED
3278       index = fieldFromInstruction32(Insn, 6, 2);
3279       if (fieldFromInstruction32(Insn, 4, 1))
3280         align = 2;
3281       break;
3282     case 2:
3283       if (fieldFromInstruction32(Insn, 6, 1))
3284         return MCDisassembler::Fail; // UNDEFINED
3285       index = fieldFromInstruction32(Insn, 7, 1);
3286       if (fieldFromInstruction32(Insn, 4, 2) != 0)
3287         align = 4;
3288   }
3289 
3290   if (Rm != 0xF) { // Writeback
3291     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3292     return MCDisassembler::Fail;
3293   }
3294   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3295     return MCDisassembler::Fail;
3296   Inst.addOperand(MCOperand::CreateImm(align));
3297   if (Rm != 0xF) {
3298     if (Rm != 0xD) {
3299       if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
3300     return MCDisassembler::Fail;
3301     } else
3302       Inst.addOperand(MCOperand::CreateReg(0));
3303   }
3304 
3305   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
3306     return MCDisassembler::Fail;
3307   Inst.addOperand(MCOperand::CreateImm(index));
3308 
3309   return S;
3310 }
3311 
3312 
3313 static DecodeStatus DecodeVLD2LN(llvm::MCInst &Inst, unsigned Insn,
3314                          uint64_t Address, const void *Decoder) {
3315   DecodeStatus S = MCDisassembler::Success;
3316 
3317   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3318   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
3319   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
3320   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
3321   unsigned size = fieldFromInstruction32(Insn, 10, 2);
3322 
3323   unsigned align = 0;
3324   unsigned index = 0;
3325   unsigned inc = 1;
3326   switch (size) {
3327     default:
3328       return MCDisassembler::Fail;
3329     case 0:
3330       index = fieldFromInstruction32(Insn, 5, 3);
3331       if (fieldFromInstruction32(Insn, 4, 1))
3332         align = 2;
3333       break;
3334     case 1:
3335       index = fieldFromInstruction32(Insn, 6, 2);
3336       if (fieldFromInstruction32(Insn, 4, 1))
3337         align = 4;
3338       if (fieldFromInstruction32(Insn, 5, 1))
3339         inc = 2;
3340       break;
3341     case 2:
3342       if (fieldFromInstruction32(Insn, 5, 1))
3343         return MCDisassembler::Fail; // UNDEFINED
3344       index = fieldFromInstruction32(Insn, 7, 1);
3345       if (fieldFromInstruction32(Insn, 4, 1) != 0)
3346         align = 8;
3347       if (fieldFromInstruction32(Insn, 6, 1))
3348         inc = 2;
3349       break;
3350   }
3351 
3352   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
3353     return MCDisassembler::Fail;
3354   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+inc, Address, Decoder)))
3355     return MCDisassembler::Fail;
3356   if (Rm != 0xF) { // Writeback
3357     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3358       return MCDisassembler::Fail;
3359   }
3360   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3361     return MCDisassembler::Fail;
3362   Inst.addOperand(MCOperand::CreateImm(align));
3363   if (Rm != 0xF) {
3364     if (Rm != 0xD) {
3365       if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
3366         return MCDisassembler::Fail;
3367     } else
3368       Inst.addOperand(MCOperand::CreateReg(0));
3369   }
3370 
3371   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
3372     return MCDisassembler::Fail;
3373   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+inc, Address, Decoder)))
3374     return MCDisassembler::Fail;
3375   Inst.addOperand(MCOperand::CreateImm(index));
3376 
3377   return S;
3378 }
3379 
3380 static DecodeStatus DecodeVST2LN(llvm::MCInst &Inst, unsigned Insn,
3381                          uint64_t Address, const void *Decoder) {
3382   DecodeStatus S = MCDisassembler::Success;
3383 
3384   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3385   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
3386   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
3387   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
3388   unsigned size = fieldFromInstruction32(Insn, 10, 2);
3389 
3390   unsigned align = 0;
3391   unsigned index = 0;
3392   unsigned inc = 1;
3393   switch (size) {
3394     default:
3395       return MCDisassembler::Fail;
3396     case 0:
3397       index = fieldFromInstruction32(Insn, 5, 3);
3398       if (fieldFromInstruction32(Insn, 4, 1))
3399         align = 2;
3400       break;
3401     case 1:
3402       index = fieldFromInstruction32(Insn, 6, 2);
3403       if (fieldFromInstruction32(Insn, 4, 1))
3404         align = 4;
3405       if (fieldFromInstruction32(Insn, 5, 1))
3406         inc = 2;
3407       break;
3408     case 2:
3409       if (fieldFromInstruction32(Insn, 5, 1))
3410         return MCDisassembler::Fail; // UNDEFINED
3411       index = fieldFromInstruction32(Insn, 7, 1);
3412       if (fieldFromInstruction32(Insn, 4, 1) != 0)
3413         align = 8;
3414       if (fieldFromInstruction32(Insn, 6, 1))
3415         inc = 2;
3416       break;
3417   }
3418 
3419   if (Rm != 0xF) { // Writeback
3420     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3421       return MCDisassembler::Fail;
3422   }
3423   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3424     return MCDisassembler::Fail;
3425   Inst.addOperand(MCOperand::CreateImm(align));
3426   if (Rm != 0xF) {
3427     if (Rm != 0xD) {
3428       if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
3429         return MCDisassembler::Fail;
3430     } else
3431       Inst.addOperand(MCOperand::CreateReg(0));
3432   }
3433 
3434   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
3435     return MCDisassembler::Fail;
3436   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+inc, Address, Decoder)))
3437     return MCDisassembler::Fail;
3438   Inst.addOperand(MCOperand::CreateImm(index));
3439 
3440   return S;
3441 }
3442 
3443 
3444 static DecodeStatus DecodeVLD3LN(llvm::MCInst &Inst, unsigned Insn,
3445                          uint64_t Address, const void *Decoder) {
3446   DecodeStatus S = MCDisassembler::Success;
3447 
3448   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3449   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
3450   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
3451   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
3452   unsigned size = fieldFromInstruction32(Insn, 10, 2);
3453 
3454   unsigned align = 0;
3455   unsigned index = 0;
3456   unsigned inc = 1;
3457   switch (size) {
3458     default:
3459       return MCDisassembler::Fail;
3460     case 0:
3461       if (fieldFromInstruction32(Insn, 4, 1))
3462         return MCDisassembler::Fail; // UNDEFINED
3463       index = fieldFromInstruction32(Insn, 5, 3);
3464       break;
3465     case 1:
3466       if (fieldFromInstruction32(Insn, 4, 1))
3467         return MCDisassembler::Fail; // UNDEFINED
3468       index = fieldFromInstruction32(Insn, 6, 2);
3469       if (fieldFromInstruction32(Insn, 5, 1))
3470         inc = 2;
3471       break;
3472     case 2:
3473       if (fieldFromInstruction32(Insn, 4, 2))
3474         return MCDisassembler::Fail; // UNDEFINED
3475       index = fieldFromInstruction32(Insn, 7, 1);
3476       if (fieldFromInstruction32(Insn, 6, 1))
3477         inc = 2;
3478       break;
3479   }
3480 
3481   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
3482     return MCDisassembler::Fail;
3483   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+inc, Address, Decoder)))
3484     return MCDisassembler::Fail;
3485   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+2*inc, Address, Decoder)))
3486     return MCDisassembler::Fail;
3487 
3488   if (Rm != 0xF) { // Writeback
3489     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3490     return MCDisassembler::Fail;
3491   }
3492   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3493     return MCDisassembler::Fail;
3494   Inst.addOperand(MCOperand::CreateImm(align));
3495   if (Rm != 0xF) {
3496     if (Rm != 0xD) {
3497       if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
3498     return MCDisassembler::Fail;
3499     } else
3500       Inst.addOperand(MCOperand::CreateReg(0));
3501   }
3502 
3503   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
3504     return MCDisassembler::Fail;
3505   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+inc, Address, Decoder)))
3506     return MCDisassembler::Fail;
3507   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+2*inc, Address, Decoder)))
3508     return MCDisassembler::Fail;
3509   Inst.addOperand(MCOperand::CreateImm(index));
3510 
3511   return S;
3512 }
3513 
3514 static DecodeStatus DecodeVST3LN(llvm::MCInst &Inst, unsigned Insn,
3515                          uint64_t Address, const void *Decoder) {
3516   DecodeStatus S = MCDisassembler::Success;
3517 
3518   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3519   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
3520   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
3521   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
3522   unsigned size = fieldFromInstruction32(Insn, 10, 2);
3523 
3524   unsigned align = 0;
3525   unsigned index = 0;
3526   unsigned inc = 1;
3527   switch (size) {
3528     default:
3529       return MCDisassembler::Fail;
3530     case 0:
3531       if (fieldFromInstruction32(Insn, 4, 1))
3532         return MCDisassembler::Fail; // UNDEFINED
3533       index = fieldFromInstruction32(Insn, 5, 3);
3534       break;
3535     case 1:
3536       if (fieldFromInstruction32(Insn, 4, 1))
3537         return MCDisassembler::Fail; // UNDEFINED
3538       index = fieldFromInstruction32(Insn, 6, 2);
3539       if (fieldFromInstruction32(Insn, 5, 1))
3540         inc = 2;
3541       break;
3542     case 2:
3543       if (fieldFromInstruction32(Insn, 4, 2))
3544         return MCDisassembler::Fail; // UNDEFINED
3545       index = fieldFromInstruction32(Insn, 7, 1);
3546       if (fieldFromInstruction32(Insn, 6, 1))
3547         inc = 2;
3548       break;
3549   }
3550 
3551   if (Rm != 0xF) { // Writeback
3552     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3553     return MCDisassembler::Fail;
3554   }
3555   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3556     return MCDisassembler::Fail;
3557   Inst.addOperand(MCOperand::CreateImm(align));
3558   if (Rm != 0xF) {
3559     if (Rm != 0xD) {
3560       if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
3561     return MCDisassembler::Fail;
3562     } else
3563       Inst.addOperand(MCOperand::CreateReg(0));
3564   }
3565 
3566   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
3567     return MCDisassembler::Fail;
3568   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+inc, Address, Decoder)))
3569     return MCDisassembler::Fail;
3570   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+2*inc, Address, Decoder)))
3571     return MCDisassembler::Fail;
3572   Inst.addOperand(MCOperand::CreateImm(index));
3573 
3574   return S;
3575 }
3576 
3577 
3578 static DecodeStatus DecodeVLD4LN(llvm::MCInst &Inst, unsigned Insn,
3579                          uint64_t Address, const void *Decoder) {
3580   DecodeStatus S = MCDisassembler::Success;
3581 
3582   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3583   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
3584   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
3585   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
3586   unsigned size = fieldFromInstruction32(Insn, 10, 2);
3587 
3588   unsigned align = 0;
3589   unsigned index = 0;
3590   unsigned inc = 1;
3591   switch (size) {
3592     default:
3593       return MCDisassembler::Fail;
3594     case 0:
3595       if (fieldFromInstruction32(Insn, 4, 1))
3596         align = 4;
3597       index = fieldFromInstruction32(Insn, 5, 3);
3598       break;
3599     case 1:
3600       if (fieldFromInstruction32(Insn, 4, 1))
3601         align = 8;
3602       index = fieldFromInstruction32(Insn, 6, 2);
3603       if (fieldFromInstruction32(Insn, 5, 1))
3604         inc = 2;
3605       break;
3606     case 2:
3607       if (fieldFromInstruction32(Insn, 4, 2))
3608         align = 4 << fieldFromInstruction32(Insn, 4, 2);
3609       index = fieldFromInstruction32(Insn, 7, 1);
3610       if (fieldFromInstruction32(Insn, 6, 1))
3611         inc = 2;
3612       break;
3613   }
3614 
3615   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
3616     return MCDisassembler::Fail;
3617   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+inc, Address, Decoder)))
3618     return MCDisassembler::Fail;
3619   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+2*inc, Address, Decoder)))
3620     return MCDisassembler::Fail;
3621   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+3*inc, Address, Decoder)))
3622     return MCDisassembler::Fail;
3623 
3624   if (Rm != 0xF) { // Writeback
3625     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3626       return MCDisassembler::Fail;
3627   }
3628   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3629     return MCDisassembler::Fail;
3630   Inst.addOperand(MCOperand::CreateImm(align));
3631   if (Rm != 0xF) {
3632     if (Rm != 0xD) {
3633       if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
3634         return MCDisassembler::Fail;
3635     } else
3636       Inst.addOperand(MCOperand::CreateReg(0));
3637   }
3638 
3639   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
3640     return MCDisassembler::Fail;
3641   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+inc, Address, Decoder)))
3642     return MCDisassembler::Fail;
3643   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+2*inc, Address, Decoder)))
3644     return MCDisassembler::Fail;
3645   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+3*inc, Address, Decoder)))
3646     return MCDisassembler::Fail;
3647   Inst.addOperand(MCOperand::CreateImm(index));
3648 
3649   return S;
3650 }
3651 
3652 static DecodeStatus DecodeVST4LN(llvm::MCInst &Inst, unsigned Insn,
3653                          uint64_t Address, const void *Decoder) {
3654   DecodeStatus S = MCDisassembler::Success;
3655 
3656   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3657   unsigned Rm = fieldFromInstruction32(Insn, 0, 4);
3658   unsigned Rd = fieldFromInstruction32(Insn, 12, 4);
3659   Rd |= fieldFromInstruction32(Insn, 22, 1) << 4;
3660   unsigned size = fieldFromInstruction32(Insn, 10, 2);
3661 
3662   unsigned align = 0;
3663   unsigned index = 0;
3664   unsigned inc = 1;
3665   switch (size) {
3666     default:
3667       return MCDisassembler::Fail;
3668     case 0:
3669       if (fieldFromInstruction32(Insn, 4, 1))
3670         align = 4;
3671       index = fieldFromInstruction32(Insn, 5, 3);
3672       break;
3673     case 1:
3674       if (fieldFromInstruction32(Insn, 4, 1))
3675         align = 8;
3676       index = fieldFromInstruction32(Insn, 6, 2);
3677       if (fieldFromInstruction32(Insn, 5, 1))
3678         inc = 2;
3679       break;
3680     case 2:
3681       if (fieldFromInstruction32(Insn, 4, 2))
3682         align = 4 << fieldFromInstruction32(Insn, 4, 2);
3683       index = fieldFromInstruction32(Insn, 7, 1);
3684       if (fieldFromInstruction32(Insn, 6, 1))
3685         inc = 2;
3686       break;
3687   }
3688 
3689   if (Rm != 0xF) { // Writeback
3690     if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3691     return MCDisassembler::Fail;
3692   }
3693   if (!Check(S, DecodeGPRRegisterClass(Inst, Rn, Address, Decoder)))
3694     return MCDisassembler::Fail;
3695   Inst.addOperand(MCOperand::CreateImm(align));
3696   if (Rm != 0xF) {
3697     if (Rm != 0xD) {
3698       if (!Check(S, DecodeGPRRegisterClass(Inst, Rm, Address, Decoder)))
3699     return MCDisassembler::Fail;
3700     } else
3701       Inst.addOperand(MCOperand::CreateReg(0));
3702   }
3703 
3704   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd, Address, Decoder)))
3705     return MCDisassembler::Fail;
3706   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+inc, Address, Decoder)))
3707     return MCDisassembler::Fail;
3708   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+2*inc, Address, Decoder)))
3709     return MCDisassembler::Fail;
3710   if (!Check(S, DecodeDPRRegisterClass(Inst, Rd+3*inc, Address, Decoder)))
3711     return MCDisassembler::Fail;
3712   Inst.addOperand(MCOperand::CreateImm(index));
3713 
3714   return S;
3715 }
3716 
3717 static DecodeStatus DecodeVMOVSRR(llvm::MCInst &Inst, unsigned Insn,
3718                                   uint64_t Address, const void *Decoder) {
3719   DecodeStatus S = MCDisassembler::Success;
3720   unsigned Rt  = fieldFromInstruction32(Insn, 12, 4);
3721   unsigned Rt2 = fieldFromInstruction32(Insn, 16, 4);
3722   unsigned Rm  = fieldFromInstruction32(Insn,  0, 4);
3723   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
3724   Rm |= fieldFromInstruction32(Insn, 5, 1) << 4;
3725 
3726   if (Rt == 0xF || Rt2 == 0xF || Rm == 0x1F)
3727     S = MCDisassembler::SoftFail;
3728 
3729   if (!Check(S, DecodeSPRRegisterClass(Inst, Rm  , Address, Decoder)))
3730     return MCDisassembler::Fail;
3731   if (!Check(S, DecodeSPRRegisterClass(Inst, Rm+1, Address, Decoder)))
3732     return MCDisassembler::Fail;
3733   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt  , Address, Decoder)))
3734     return MCDisassembler::Fail;
3735   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt2 , Address, Decoder)))
3736     return MCDisassembler::Fail;
3737   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
3738     return MCDisassembler::Fail;
3739 
3740   return S;
3741 }
3742 
3743 static DecodeStatus DecodeVMOVRRS(llvm::MCInst &Inst, unsigned Insn,
3744                                   uint64_t Address, const void *Decoder) {
3745   DecodeStatus S = MCDisassembler::Success;
3746   unsigned Rt  = fieldFromInstruction32(Insn, 12, 4);
3747   unsigned Rt2 = fieldFromInstruction32(Insn, 16, 4);
3748   unsigned Rm  = fieldFromInstruction32(Insn,  0, 4);
3749   unsigned pred = fieldFromInstruction32(Insn, 28, 4);
3750   Rm |= fieldFromInstruction32(Insn, 5, 1) << 4;
3751 
3752   if (Rt == 0xF || Rt2 == 0xF || Rm == 0x1F)
3753     S = MCDisassembler::SoftFail;
3754 
3755   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt  , Address, Decoder)))
3756     return MCDisassembler::Fail;
3757   if (!Check(S, DecodeGPRRegisterClass(Inst, Rt2 , Address, Decoder)))
3758     return MCDisassembler::Fail;
3759   if (!Check(S, DecodeSPRRegisterClass(Inst, Rm  , Address, Decoder)))
3760     return MCDisassembler::Fail;
3761   if (!Check(S, DecodeSPRRegisterClass(Inst, Rm+1, Address, Decoder)))
3762     return MCDisassembler::Fail;
3763   if (!Check(S, DecodePredicateOperand(Inst, pred, Address, Decoder)))
3764     return MCDisassembler::Fail;
3765 
3766   return S;
3767 }
3768 
3769 static DecodeStatus DecodeIT(llvm::MCInst &Inst, unsigned Insn,
3770                              uint64_t Address, const void *Decoder) {
3771   DecodeStatus S = MCDisassembler::Success;
3772   unsigned pred = fieldFromInstruction16(Insn, 4, 4);
3773   // The InstPrinter needs to have the low bit of the predicate in
3774   // the mask operand to be able to print it properly.
3775   unsigned mask = fieldFromInstruction16(Insn, 0, 5);
3776 
3777   if (pred == 0xF) {
3778     pred = 0xE;
3779     S = MCDisassembler::SoftFail;
3780   }
3781 
3782   if ((mask & 0xF) == 0) {
3783     // Preserve the high bit of the mask, which is the low bit of
3784     // the predicate.
3785     mask &= 0x10;
3786     mask |= 0x8;
3787     S = MCDisassembler::SoftFail;
3788   }
3789 
3790   Inst.addOperand(MCOperand::CreateImm(pred));
3791   Inst.addOperand(MCOperand::CreateImm(mask));
3792   return S;
3793 }
3794 
3795 static DecodeStatus
3796 DecodeT2LDRDPreInstruction(llvm::MCInst &Inst, unsigned Insn,
3797                            uint64_t Address, const void *Decoder) {
3798   DecodeStatus S = MCDisassembler::Success;
3799 
3800   unsigned Rt = fieldFromInstruction32(Insn, 12, 4);
3801   unsigned Rt2 = fieldFromInstruction32(Insn, 8, 4);
3802   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3803   unsigned addr = fieldFromInstruction32(Insn, 0, 8);
3804   unsigned W = fieldFromInstruction32(Insn, 21, 1);
3805   unsigned U = fieldFromInstruction32(Insn, 23, 1);
3806   unsigned P = fieldFromInstruction32(Insn, 24, 1);
3807   bool writeback = (W == 1) | (P == 0);
3808 
3809   addr |= (U << 8) | (Rn << 9);
3810 
3811   if (writeback && (Rn == Rt || Rn == Rt2))
3812     Check(S, MCDisassembler::SoftFail);
3813   if (Rt == Rt2)
3814     Check(S, MCDisassembler::SoftFail);
3815 
3816   // Rt
3817   if (!Check(S, DecoderGPRRegisterClass(Inst, Rt, Address, Decoder)))
3818     return MCDisassembler::Fail;
3819   // Rt2
3820   if (!Check(S, DecoderGPRRegisterClass(Inst, Rt2, Address, Decoder)))
3821     return MCDisassembler::Fail;
3822   // Writeback operand
3823   if (!Check(S, DecoderGPRRegisterClass(Inst, Rn, Address, Decoder)))
3824     return MCDisassembler::Fail;
3825   // addr
3826   if (!Check(S, DecodeT2AddrModeImm8s4(Inst, addr, Address, Decoder)))
3827     return MCDisassembler::Fail;
3828 
3829   return S;
3830 }
3831 
3832 static DecodeStatus
3833 DecodeT2STRDPreInstruction(llvm::MCInst &Inst, unsigned Insn,
3834                            uint64_t Address, const void *Decoder) {
3835   DecodeStatus S = MCDisassembler::Success;
3836 
3837   unsigned Rt = fieldFromInstruction32(Insn, 12, 4);
3838   unsigned Rt2 = fieldFromInstruction32(Insn, 8, 4);
3839   unsigned Rn = fieldFromInstruction32(Insn, 16, 4);
3840   unsigned addr = fieldFromInstruction32(Insn, 0, 8);
3841   unsigned W = fieldFromInstruction32(Insn, 21, 1);
3842   unsigned U = fieldFromInstruction32(Insn, 23, 1);
3843   unsigned P = fieldFromInstruction32(Insn, 24, 1);
3844   bool writeback = (W == 1) | (P == 0);
3845 
3846   addr |= (U << 8) | (Rn << 9);
3847 
3848   if (writeback && (Rn == Rt || Rn == Rt2))
3849     Check(S, MCDisassembler::SoftFail);
3850 
3851   // Writeback operand
3852   if (!Check(S, DecoderGPRRegisterClass(Inst, Rn, Address, Decoder)))
3853     return MCDisassembler::Fail;
3854   // Rt
3855   if (!Check(S, DecoderGPRRegisterClass(Inst, Rt, Address, Decoder)))
3856     return MCDisassembler::Fail;
3857   // Rt2
3858   if (!Check(S, DecoderGPRRegisterClass(Inst, Rt2, Address, Decoder)))
3859     return MCDisassembler::Fail;
3860   // addr
3861   if (!Check(S, DecodeT2AddrModeImm8s4(Inst, addr, Address, Decoder)))
3862     return MCDisassembler::Fail;
3863 
3864   return S;
3865 }
3866 
3867 static DecodeStatus DecodeT2Adr(llvm::MCInst &Inst, uint32_t Insn,
3868                                 uint64_t Address, const void *Decoder) {
3869   unsigned sign1 = fieldFromInstruction32(Insn, 21, 1);
3870   unsigned sign2 = fieldFromInstruction32(Insn, 23, 1);
3871   if (sign1 != sign2) return MCDisassembler::Fail;
3872 
3873   unsigned Val = fieldFromInstruction32(Insn, 0, 8);
3874   Val |= fieldFromInstruction32(Insn, 12, 3) << 8;
3875   Val |= fieldFromInstruction32(Insn, 26, 1) << 11;
3876   Val |= sign1 << 12;
3877   Inst.addOperand(MCOperand::CreateImm(SignExtend32<13>(Val)));
3878 
3879   return MCDisassembler::Success;
3880 }
3881 
3882 static DecodeStatus DecodeT2ShifterImmOperand(llvm::MCInst &Inst, uint32_t Val,
3883                                               uint64_t Address,
3884                                               const void *Decoder) {
3885   DecodeStatus S = MCDisassembler::Success;
3886 
3887   // Shift of "asr #32" is not allowed in Thumb2 mode.
3888   if (Val == 0x20) S = MCDisassembler::SoftFail;
3889   Inst.addOperand(MCOperand::CreateImm(Val));
3890   return S;
3891 }
3892 
3893