xref: /llvm-project/llvm/lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp (revision 0b4eb1ead18e437b3f630bf3f4c082adab417170)
1 //===- AMDGPUDisassembler.cpp - Disassembler for AMDGPU ISA ---------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 //===----------------------------------------------------------------------===//
11 //
12 /// \file
13 ///
14 /// This file contains definition for AMDGPU ISA disassembler
15 //
16 //===----------------------------------------------------------------------===//
17 
18 // ToDo: What to do with instruction suffixes (v_mov_b32 vs v_mov_b32_e32)?
19 
20 #include "Disassembler/AMDGPUDisassembler.h"
21 #include "AMDGPU.h"
22 #include "AMDGPURegisterInfo.h"
23 #include "SIDefines.h"
24 #include "Utils/AMDGPUBaseInfo.h"
25 #include "llvm-c/Disassembler.h"
26 #include "llvm/ADT/APInt.h"
27 #include "llvm/ADT/ArrayRef.h"
28 #include "llvm/ADT/Twine.h"
29 #include "llvm/BinaryFormat/ELF.h"
30 #include "llvm/MC/MCContext.h"
31 #include "llvm/MC/MCDisassembler/MCDisassembler.h"
32 #include "llvm/MC/MCExpr.h"
33 #include "llvm/MC/MCFixedLenDisassembler.h"
34 #include "llvm/MC/MCInst.h"
35 #include "llvm/MC/MCSubtargetInfo.h"
36 #include "llvm/Support/Endian.h"
37 #include "llvm/Support/ErrorHandling.h"
38 #include "llvm/Support/MathExtras.h"
39 #include "llvm/Support/TargetRegistry.h"
40 #include "llvm/Support/raw_ostream.h"
41 #include <algorithm>
42 #include <cassert>
43 #include <cstddef>
44 #include <cstdint>
45 #include <iterator>
46 #include <tuple>
47 #include <vector>
48 
49 using namespace llvm;
50 
51 #define DEBUG_TYPE "amdgpu-disassembler"
52 
53 using DecodeStatus = llvm::MCDisassembler::DecodeStatus;
54 
55 inline static MCDisassembler::DecodeStatus
56 addOperand(MCInst &Inst, const MCOperand& Opnd) {
57   Inst.addOperand(Opnd);
58   return Opnd.isValid() ?
59     MCDisassembler::Success :
60     MCDisassembler::SoftFail;
61 }
62 
63 static int insertNamedMCOperand(MCInst &MI, const MCOperand &Op,
64                                 uint16_t NameIdx) {
65   int OpIdx = AMDGPU::getNamedOperandIdx(MI.getOpcode(), NameIdx);
66   if (OpIdx != -1) {
67     auto I = MI.begin();
68     std::advance(I, OpIdx);
69     MI.insert(I, Op);
70   }
71   return OpIdx;
72 }
73 
74 static DecodeStatus decodeSoppBrTarget(MCInst &Inst, unsigned Imm,
75                                        uint64_t Addr, const void *Decoder) {
76   auto DAsm = static_cast<const AMDGPUDisassembler*>(Decoder);
77 
78   APInt SignedOffset(18, Imm * 4, true);
79   int64_t Offset = (SignedOffset.sext(64) + 4 + Addr).getSExtValue();
80 
81   if (DAsm->tryAddingSymbolicOperand(Inst, Offset, Addr, true, 2, 2))
82     return MCDisassembler::Success;
83   return addOperand(Inst, MCOperand::createImm(Imm));
84 }
85 
86 #define DECODE_OPERAND(StaticDecoderName, DecoderName) \
87 static DecodeStatus StaticDecoderName(MCInst &Inst, \
88                                        unsigned Imm, \
89                                        uint64_t /*Addr*/, \
90                                        const void *Decoder) { \
91   auto DAsm = static_cast<const AMDGPUDisassembler*>(Decoder); \
92   return addOperand(Inst, DAsm->DecoderName(Imm)); \
93 }
94 
95 #define DECODE_OPERAND_REG(RegClass) \
96 DECODE_OPERAND(Decode##RegClass##RegisterClass, decodeOperand_##RegClass)
97 
98 DECODE_OPERAND_REG(VGPR_32)
99 DECODE_OPERAND_REG(VS_32)
100 DECODE_OPERAND_REG(VS_64)
101 DECODE_OPERAND_REG(VS_128)
102 
103 DECODE_OPERAND_REG(VReg_64)
104 DECODE_OPERAND_REG(VReg_96)
105 DECODE_OPERAND_REG(VReg_128)
106 
107 DECODE_OPERAND_REG(SReg_32)
108 DECODE_OPERAND_REG(SReg_32_XM0_XEXEC)
109 DECODE_OPERAND_REG(SReg_32_XEXEC_HI)
110 DECODE_OPERAND_REG(SReg_64)
111 DECODE_OPERAND_REG(SReg_64_XEXEC)
112 DECODE_OPERAND_REG(SReg_128)
113 DECODE_OPERAND_REG(SReg_256)
114 DECODE_OPERAND_REG(SReg_512)
115 
116 static DecodeStatus decodeOperand_VSrc16(MCInst &Inst,
117                                          unsigned Imm,
118                                          uint64_t Addr,
119                                          const void *Decoder) {
120   auto DAsm = static_cast<const AMDGPUDisassembler*>(Decoder);
121   return addOperand(Inst, DAsm->decodeOperand_VSrc16(Imm));
122 }
123 
124 static DecodeStatus decodeOperand_VSrcV216(MCInst &Inst,
125                                          unsigned Imm,
126                                          uint64_t Addr,
127                                          const void *Decoder) {
128   auto DAsm = static_cast<const AMDGPUDisassembler*>(Decoder);
129   return addOperand(Inst, DAsm->decodeOperand_VSrcV216(Imm));
130 }
131 
132 #define DECODE_SDWA(DecName) \
133 DECODE_OPERAND(decodeSDWA##DecName, decodeSDWA##DecName)
134 
135 DECODE_SDWA(Src32)
136 DECODE_SDWA(Src16)
137 DECODE_SDWA(VopcDst)
138 
139 #include "AMDGPUGenDisassemblerTables.inc"
140 
141 //===----------------------------------------------------------------------===//
142 //
143 //===----------------------------------------------------------------------===//
144 
145 template <typename T> static inline T eatBytes(ArrayRef<uint8_t>& Bytes) {
146   assert(Bytes.size() >= sizeof(T));
147   const auto Res = support::endian::read<T, support::endianness::little>(Bytes.data());
148   Bytes = Bytes.slice(sizeof(T));
149   return Res;
150 }
151 
152 DecodeStatus AMDGPUDisassembler::tryDecodeInst(const uint8_t* Table,
153                                                MCInst &MI,
154                                                uint64_t Inst,
155                                                uint64_t Address) const {
156   assert(MI.getOpcode() == 0);
157   assert(MI.getNumOperands() == 0);
158   MCInst TmpInst;
159   HasLiteral = false;
160   const auto SavedBytes = Bytes;
161   if (decodeInstruction(Table, TmpInst, Inst, Address, this, STI)) {
162     MI = TmpInst;
163     return MCDisassembler::Success;
164   }
165   Bytes = SavedBytes;
166   return MCDisassembler::Fail;
167 }
168 
169 DecodeStatus AMDGPUDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
170                                                 ArrayRef<uint8_t> Bytes_,
171                                                 uint64_t Address,
172                                                 raw_ostream &WS,
173                                                 raw_ostream &CS) const {
174   CommentStream = &CS;
175   bool IsSDWA = false;
176 
177   // ToDo: AMDGPUDisassembler supports only VI ISA.
178   if (!STI.getFeatureBits()[AMDGPU::FeatureGCN3Encoding])
179     report_fatal_error("Disassembly not yet supported for subtarget");
180 
181   const unsigned MaxInstBytesNum = (std::min)((size_t)8, Bytes_.size());
182   Bytes = Bytes_.slice(0, MaxInstBytesNum);
183 
184   DecodeStatus Res = MCDisassembler::Fail;
185   do {
186     // ToDo: better to switch encoding length using some bit predicate
187     // but it is unknown yet, so try all we can
188 
189     // Try to decode DPP and SDWA first to solve conflict with VOP1 and VOP2
190     // encodings
191     if (Bytes.size() >= 8) {
192       const uint64_t QW = eatBytes<uint64_t>(Bytes);
193       Res = tryDecodeInst(DecoderTableDPP64, MI, QW, Address);
194       if (Res) break;
195 
196       Res = tryDecodeInst(DecoderTableSDWA64, MI, QW, Address);
197       if (Res) { IsSDWA = true;  break; }
198 
199       Res = tryDecodeInst(DecoderTableSDWA964, MI, QW, Address);
200       if (Res) { IsSDWA = true;  break; }
201     }
202 
203     // Reinitialize Bytes as DPP64 could have eaten too much
204     Bytes = Bytes_.slice(0, MaxInstBytesNum);
205 
206     // Try decode 32-bit instruction
207     if (Bytes.size() < 4) break;
208     const uint32_t DW = eatBytes<uint32_t>(Bytes);
209     Res = tryDecodeInst(DecoderTableVI32, MI, DW, Address);
210     if (Res) break;
211 
212     Res = tryDecodeInst(DecoderTableAMDGPU32, MI, DW, Address);
213     if (Res) break;
214 
215     Res = tryDecodeInst(DecoderTableGFX932, MI, DW, Address);
216     if (Res) break;
217 
218     if (Bytes.size() < 4) break;
219     const uint64_t QW = ((uint64_t)eatBytes<uint32_t>(Bytes) << 32) | DW;
220     Res = tryDecodeInst(DecoderTableVI64, MI, QW, Address);
221     if (Res) break;
222 
223     Res = tryDecodeInst(DecoderTableAMDGPU64, MI, QW, Address);
224     if (Res) break;
225 
226     Res = tryDecodeInst(DecoderTableGFX964, MI, QW, Address);
227   } while (false);
228 
229   if (Res && (MI.getOpcode() == AMDGPU::V_MAC_F32_e64_vi ||
230               MI.getOpcode() == AMDGPU::V_MAC_F32_e64_si ||
231               MI.getOpcode() == AMDGPU::V_MAC_F16_e64_vi)) {
232     // Insert dummy unused src2_modifiers.
233     insertNamedMCOperand(MI, MCOperand::createImm(0),
234                          AMDGPU::OpName::src2_modifiers);
235   }
236 
237   if (Res && (MCII->get(MI.getOpcode()).TSFlags & SIInstrFlags::MIMG)) {
238     Res = convertMIMGInst(MI);
239   }
240 
241   if (Res && IsSDWA)
242     Res = convertSDWAInst(MI);
243 
244   Size = Res ? (MaxInstBytesNum - Bytes.size()) : 0;
245   return Res;
246 }
247 
248 DecodeStatus AMDGPUDisassembler::convertSDWAInst(MCInst &MI) const {
249   if (STI.getFeatureBits()[AMDGPU::FeatureGFX9]) {
250     if (AMDGPU::getNamedOperandIdx(MI.getOpcode(), AMDGPU::OpName::sdst) != -1)
251       // VOPC - insert clamp
252       insertNamedMCOperand(MI, MCOperand::createImm(0), AMDGPU::OpName::clamp);
253   } else if (STI.getFeatureBits()[AMDGPU::FeatureVolcanicIslands]) {
254     int SDst = AMDGPU::getNamedOperandIdx(MI.getOpcode(), AMDGPU::OpName::sdst);
255     if (SDst != -1) {
256       // VOPC - insert VCC register as sdst
257       insertNamedMCOperand(MI, createRegOperand(AMDGPU::VCC),
258                            AMDGPU::OpName::sdst);
259     } else {
260       // VOP1/2 - insert omod if present in instruction
261       insertNamedMCOperand(MI, MCOperand::createImm(0), AMDGPU::OpName::omod);
262     }
263   }
264   return MCDisassembler::Success;
265 }
266 
267 DecodeStatus AMDGPUDisassembler::convertMIMGInst(MCInst &MI) const {
268   int VDstIdx = AMDGPU::getNamedOperandIdx(MI.getOpcode(),
269                                            AMDGPU::OpName::vdst);
270 
271   int VDataIdx = AMDGPU::getNamedOperandIdx(MI.getOpcode(),
272                                             AMDGPU::OpName::vdata);
273 
274   int DMaskIdx = AMDGPU::getNamedOperandIdx(MI.getOpcode(),
275                                             AMDGPU::OpName::dmask);
276 
277   assert(VDataIdx != -1);
278   assert(DMaskIdx != -1);
279 
280   bool isAtomic = (VDstIdx != -1);
281 
282   unsigned DMask = MI.getOperand(DMaskIdx).getImm() & 0xf;
283   if (DMask == 0)
284     return MCDisassembler::Success;
285 
286   unsigned ChannelCount = countPopulation(DMask);
287   if (ChannelCount == 1)
288     return MCDisassembler::Success;
289 
290   int NewOpcode = -1;
291 
292   if (isAtomic) {
293     if (DMask == 0x1 || DMask == 0x3 || DMask == 0xF) {
294       NewOpcode = AMDGPU::getMaskedMIMGAtomicOp(*MCII, MI.getOpcode(), ChannelCount);
295     }
296     if (NewOpcode == -1) return MCDisassembler::Success;
297   } else {
298     NewOpcode = AMDGPU::getMaskedMIMGOp(*MCII, MI.getOpcode(), ChannelCount);
299     assert(NewOpcode != -1 && "could not find matching mimg channel instruction");
300   }
301 
302   auto RCID = MCII->get(NewOpcode).OpInfo[VDataIdx].RegClass;
303 
304   // Get first subregister of VData
305   unsigned Vdata0 = MI.getOperand(VDataIdx).getReg();
306   unsigned VdataSub0 = MRI.getSubReg(Vdata0, AMDGPU::sub0);
307   Vdata0 = (VdataSub0 != 0)? VdataSub0 : Vdata0;
308 
309   // Widen the register to the correct number of enabled channels.
310   auto NewVdata = MRI.getMatchingSuperReg(Vdata0, AMDGPU::sub0,
311                                           &MRI.getRegClass(RCID));
312   if (NewVdata == AMDGPU::NoRegister) {
313     // It's possible to encode this such that the low register + enabled
314     // components exceeds the register count.
315     return MCDisassembler::Success;
316   }
317 
318   MI.setOpcode(NewOpcode);
319   // vaddr will be always appear as a single VGPR. This will look different than
320   // how it is usually emitted because the number of register components is not
321   // in the instruction encoding.
322   MI.getOperand(VDataIdx) = MCOperand::createReg(NewVdata);
323 
324   if (isAtomic) {
325     // Atomic operations have an additional operand (a copy of data)
326     MI.getOperand(VDstIdx) = MCOperand::createReg(NewVdata);
327   }
328 
329   return MCDisassembler::Success;
330 }
331 
332 const char* AMDGPUDisassembler::getRegClassName(unsigned RegClassID) const {
333   return getContext().getRegisterInfo()->
334     getRegClassName(&AMDGPUMCRegisterClasses[RegClassID]);
335 }
336 
337 inline
338 MCOperand AMDGPUDisassembler::errOperand(unsigned V,
339                                          const Twine& ErrMsg) const {
340   *CommentStream << "Error: " + ErrMsg;
341 
342   // ToDo: add support for error operands to MCInst.h
343   // return MCOperand::createError(V);
344   return MCOperand();
345 }
346 
347 inline
348 MCOperand AMDGPUDisassembler::createRegOperand(unsigned int RegId) const {
349   return MCOperand::createReg(AMDGPU::getMCReg(RegId, STI));
350 }
351 
352 inline
353 MCOperand AMDGPUDisassembler::createRegOperand(unsigned RegClassID,
354                                                unsigned Val) const {
355   const auto& RegCl = AMDGPUMCRegisterClasses[RegClassID];
356   if (Val >= RegCl.getNumRegs())
357     return errOperand(Val, Twine(getRegClassName(RegClassID)) +
358                            ": unknown register " + Twine(Val));
359   return createRegOperand(RegCl.getRegister(Val));
360 }
361 
362 inline
363 MCOperand AMDGPUDisassembler::createSRegOperand(unsigned SRegClassID,
364                                                 unsigned Val) const {
365   // ToDo: SI/CI have 104 SGPRs, VI - 102
366   // Valery: here we accepting as much as we can, let assembler sort it out
367   int shift = 0;
368   switch (SRegClassID) {
369   case AMDGPU::SGPR_32RegClassID:
370   case AMDGPU::TTMP_32RegClassID:
371     break;
372   case AMDGPU::SGPR_64RegClassID:
373   case AMDGPU::TTMP_64RegClassID:
374     shift = 1;
375     break;
376   case AMDGPU::SGPR_128RegClassID:
377   case AMDGPU::TTMP_128RegClassID:
378   // ToDo: unclear if s[100:104] is available on VI. Can we use VCC as SGPR in
379   // this bundle?
380   case AMDGPU::SGPR_256RegClassID:
381   case AMDGPU::TTMP_256RegClassID:
382     // ToDo: unclear if s[96:104] is available on VI. Can we use VCC as SGPR in
383   // this bundle?
384   case AMDGPU::SGPR_512RegClassID:
385   case AMDGPU::TTMP_512RegClassID:
386     shift = 2;
387     break;
388   // ToDo: unclear if s[88:104] is available on VI. Can we use VCC as SGPR in
389   // this bundle?
390   default:
391     llvm_unreachable("unhandled register class");
392   }
393 
394   if (Val % (1 << shift)) {
395     *CommentStream << "Warning: " << getRegClassName(SRegClassID)
396                    << ": scalar reg isn't aligned " << Val;
397   }
398 
399   return createRegOperand(SRegClassID, Val >> shift);
400 }
401 
402 MCOperand AMDGPUDisassembler::decodeOperand_VS_32(unsigned Val) const {
403   return decodeSrcOp(OPW32, Val);
404 }
405 
406 MCOperand AMDGPUDisassembler::decodeOperand_VS_64(unsigned Val) const {
407   return decodeSrcOp(OPW64, Val);
408 }
409 
410 MCOperand AMDGPUDisassembler::decodeOperand_VS_128(unsigned Val) const {
411   return decodeSrcOp(OPW128, Val);
412 }
413 
414 MCOperand AMDGPUDisassembler::decodeOperand_VSrc16(unsigned Val) const {
415   return decodeSrcOp(OPW16, Val);
416 }
417 
418 MCOperand AMDGPUDisassembler::decodeOperand_VSrcV216(unsigned Val) const {
419   return decodeSrcOp(OPWV216, Val);
420 }
421 
422 MCOperand AMDGPUDisassembler::decodeOperand_VGPR_32(unsigned Val) const {
423   // Some instructions have operand restrictions beyond what the encoding
424   // allows. Some ordinarily VSrc_32 operands are VGPR_32, so clear the extra
425   // high bit.
426   Val &= 255;
427 
428   return createRegOperand(AMDGPU::VGPR_32RegClassID, Val);
429 }
430 
431 MCOperand AMDGPUDisassembler::decodeOperand_VReg_64(unsigned Val) const {
432   return createRegOperand(AMDGPU::VReg_64RegClassID, Val);
433 }
434 
435 MCOperand AMDGPUDisassembler::decodeOperand_VReg_96(unsigned Val) const {
436   return createRegOperand(AMDGPU::VReg_96RegClassID, Val);
437 }
438 
439 MCOperand AMDGPUDisassembler::decodeOperand_VReg_128(unsigned Val) const {
440   return createRegOperand(AMDGPU::VReg_128RegClassID, Val);
441 }
442 
443 MCOperand AMDGPUDisassembler::decodeOperand_SReg_32(unsigned Val) const {
444   // table-gen generated disassembler doesn't care about operand types
445   // leaving only registry class so SSrc_32 operand turns into SReg_32
446   // and therefore we accept immediates and literals here as well
447   return decodeSrcOp(OPW32, Val);
448 }
449 
450 MCOperand AMDGPUDisassembler::decodeOperand_SReg_32_XM0_XEXEC(
451   unsigned Val) const {
452   // SReg_32_XM0 is SReg_32 without M0 or EXEC_LO/EXEC_HI
453   return decodeOperand_SReg_32(Val);
454 }
455 
456 MCOperand AMDGPUDisassembler::decodeOperand_SReg_32_XEXEC_HI(
457   unsigned Val) const {
458   // SReg_32_XM0 is SReg_32 without EXEC_HI
459   return decodeOperand_SReg_32(Val);
460 }
461 
462 MCOperand AMDGPUDisassembler::decodeOperand_SReg_64(unsigned Val) const {
463   return decodeSrcOp(OPW64, Val);
464 }
465 
466 MCOperand AMDGPUDisassembler::decodeOperand_SReg_64_XEXEC(unsigned Val) const {
467   return decodeSrcOp(OPW64, Val);
468 }
469 
470 MCOperand AMDGPUDisassembler::decodeOperand_SReg_128(unsigned Val) const {
471   return decodeSrcOp(OPW128, Val);
472 }
473 
474 MCOperand AMDGPUDisassembler::decodeOperand_SReg_256(unsigned Val) const {
475   return decodeDstOp(OPW256, Val);
476 }
477 
478 MCOperand AMDGPUDisassembler::decodeOperand_SReg_512(unsigned Val) const {
479   return decodeDstOp(OPW512, Val);
480 }
481 
482 MCOperand AMDGPUDisassembler::decodeLiteralConstant() const {
483   // For now all literal constants are supposed to be unsigned integer
484   // ToDo: deal with signed/unsigned 64-bit integer constants
485   // ToDo: deal with float/double constants
486   if (!HasLiteral) {
487     if (Bytes.size() < 4) {
488       return errOperand(0, "cannot read literal, inst bytes left " +
489                         Twine(Bytes.size()));
490     }
491     HasLiteral = true;
492     Literal = eatBytes<uint32_t>(Bytes);
493   }
494   return MCOperand::createImm(Literal);
495 }
496 
497 MCOperand AMDGPUDisassembler::decodeIntImmed(unsigned Imm) {
498   using namespace AMDGPU::EncValues;
499 
500   assert(Imm >= INLINE_INTEGER_C_MIN && Imm <= INLINE_INTEGER_C_MAX);
501   return MCOperand::createImm((Imm <= INLINE_INTEGER_C_POSITIVE_MAX) ?
502     (static_cast<int64_t>(Imm) - INLINE_INTEGER_C_MIN) :
503     (INLINE_INTEGER_C_POSITIVE_MAX - static_cast<int64_t>(Imm)));
504       // Cast prevents negative overflow.
505 }
506 
507 static int64_t getInlineImmVal32(unsigned Imm) {
508   switch (Imm) {
509   case 240:
510     return FloatToBits(0.5f);
511   case 241:
512     return FloatToBits(-0.5f);
513   case 242:
514     return FloatToBits(1.0f);
515   case 243:
516     return FloatToBits(-1.0f);
517   case 244:
518     return FloatToBits(2.0f);
519   case 245:
520     return FloatToBits(-2.0f);
521   case 246:
522     return FloatToBits(4.0f);
523   case 247:
524     return FloatToBits(-4.0f);
525   case 248: // 1 / (2 * PI)
526     return 0x3e22f983;
527   default:
528     llvm_unreachable("invalid fp inline imm");
529   }
530 }
531 
532 static int64_t getInlineImmVal64(unsigned Imm) {
533   switch (Imm) {
534   case 240:
535     return DoubleToBits(0.5);
536   case 241:
537     return DoubleToBits(-0.5);
538   case 242:
539     return DoubleToBits(1.0);
540   case 243:
541     return DoubleToBits(-1.0);
542   case 244:
543     return DoubleToBits(2.0);
544   case 245:
545     return DoubleToBits(-2.0);
546   case 246:
547     return DoubleToBits(4.0);
548   case 247:
549     return DoubleToBits(-4.0);
550   case 248: // 1 / (2 * PI)
551     return 0x3fc45f306dc9c882;
552   default:
553     llvm_unreachable("invalid fp inline imm");
554   }
555 }
556 
557 static int64_t getInlineImmVal16(unsigned Imm) {
558   switch (Imm) {
559   case 240:
560     return 0x3800;
561   case 241:
562     return 0xB800;
563   case 242:
564     return 0x3C00;
565   case 243:
566     return 0xBC00;
567   case 244:
568     return 0x4000;
569   case 245:
570     return 0xC000;
571   case 246:
572     return 0x4400;
573   case 247:
574     return 0xC400;
575   case 248: // 1 / (2 * PI)
576     return 0x3118;
577   default:
578     llvm_unreachable("invalid fp inline imm");
579   }
580 }
581 
582 MCOperand AMDGPUDisassembler::decodeFPImmed(OpWidthTy Width, unsigned Imm) {
583   assert(Imm >= AMDGPU::EncValues::INLINE_FLOATING_C_MIN
584       && Imm <= AMDGPU::EncValues::INLINE_FLOATING_C_MAX);
585 
586   // ToDo: case 248: 1/(2*PI) - is allowed only on VI
587   switch (Width) {
588   case OPW32:
589     return MCOperand::createImm(getInlineImmVal32(Imm));
590   case OPW64:
591     return MCOperand::createImm(getInlineImmVal64(Imm));
592   case OPW16:
593   case OPWV216:
594     return MCOperand::createImm(getInlineImmVal16(Imm));
595   default:
596     llvm_unreachable("implement me");
597   }
598 }
599 
600 unsigned AMDGPUDisassembler::getVgprClassId(const OpWidthTy Width) const {
601   using namespace AMDGPU;
602 
603   assert(OPW_FIRST_ <= Width && Width < OPW_LAST_);
604   switch (Width) {
605   default: // fall
606   case OPW32:
607   case OPW16:
608   case OPWV216:
609     return VGPR_32RegClassID;
610   case OPW64: return VReg_64RegClassID;
611   case OPW128: return VReg_128RegClassID;
612   }
613 }
614 
615 unsigned AMDGPUDisassembler::getSgprClassId(const OpWidthTy Width) const {
616   using namespace AMDGPU;
617 
618   assert(OPW_FIRST_ <= Width && Width < OPW_LAST_);
619   switch (Width) {
620   default: // fall
621   case OPW32:
622   case OPW16:
623   case OPWV216:
624     return SGPR_32RegClassID;
625   case OPW64: return SGPR_64RegClassID;
626   case OPW128: return SGPR_128RegClassID;
627   case OPW256: return SGPR_256RegClassID;
628   case OPW512: return SGPR_512RegClassID;
629   }
630 }
631 
632 unsigned AMDGPUDisassembler::getTtmpClassId(const OpWidthTy Width) const {
633   using namespace AMDGPU;
634 
635   assert(OPW_FIRST_ <= Width && Width < OPW_LAST_);
636   switch (Width) {
637   default: // fall
638   case OPW32:
639   case OPW16:
640   case OPWV216:
641     return TTMP_32RegClassID;
642   case OPW64: return TTMP_64RegClassID;
643   case OPW128: return TTMP_128RegClassID;
644   case OPW256: return TTMP_256RegClassID;
645   case OPW512: return TTMP_512RegClassID;
646   }
647 }
648 
649 int AMDGPUDisassembler::getTTmpIdx(unsigned Val) const {
650   using namespace AMDGPU::EncValues;
651 
652   unsigned TTmpMin = isGFX9() ? TTMP_GFX9_MIN : TTMP_VI_MIN;
653   unsigned TTmpMax = isGFX9() ? TTMP_GFX9_MAX : TTMP_VI_MAX;
654 
655   return (TTmpMin <= Val && Val <= TTmpMax)? Val - TTmpMin : -1;
656 }
657 
658 MCOperand AMDGPUDisassembler::decodeSrcOp(const OpWidthTy Width, unsigned Val) const {
659   using namespace AMDGPU::EncValues;
660 
661   assert(Val < 512); // enum9
662 
663   if (VGPR_MIN <= Val && Val <= VGPR_MAX) {
664     return createRegOperand(getVgprClassId(Width), Val - VGPR_MIN);
665   }
666   if (Val <= SGPR_MAX) {
667     assert(SGPR_MIN == 0); // "SGPR_MIN <= Val" is always true and causes compilation warning.
668     return createSRegOperand(getSgprClassId(Width), Val - SGPR_MIN);
669   }
670 
671   int TTmpIdx = getTTmpIdx(Val);
672   if (TTmpIdx >= 0) {
673     return createSRegOperand(getTtmpClassId(Width), TTmpIdx);
674   }
675 
676   if (INLINE_INTEGER_C_MIN <= Val && Val <= INLINE_INTEGER_C_MAX)
677     return decodeIntImmed(Val);
678 
679   if (INLINE_FLOATING_C_MIN <= Val && Val <= INLINE_FLOATING_C_MAX)
680     return decodeFPImmed(Width, Val);
681 
682   if (Val == LITERAL_CONST)
683     return decodeLiteralConstant();
684 
685   switch (Width) {
686   case OPW32:
687   case OPW16:
688   case OPWV216:
689     return decodeSpecialReg32(Val);
690   case OPW64:
691     return decodeSpecialReg64(Val);
692   default:
693     llvm_unreachable("unexpected immediate type");
694   }
695 }
696 
697 MCOperand AMDGPUDisassembler::decodeDstOp(const OpWidthTy Width, unsigned Val) const {
698   using namespace AMDGPU::EncValues;
699 
700   assert(Val < 128);
701   assert(Width == OPW256 || Width == OPW512);
702 
703   if (Val <= SGPR_MAX) {
704     assert(SGPR_MIN == 0); // "SGPR_MIN <= Val" is always true and causes compilation warning.
705     return createSRegOperand(getSgprClassId(Width), Val - SGPR_MIN);
706   }
707 
708   int TTmpIdx = getTTmpIdx(Val);
709   if (TTmpIdx >= 0) {
710     return createSRegOperand(getTtmpClassId(Width), TTmpIdx);
711   }
712 
713   llvm_unreachable("unknown dst register");
714 }
715 
716 MCOperand AMDGPUDisassembler::decodeSpecialReg32(unsigned Val) const {
717   using namespace AMDGPU;
718 
719   switch (Val) {
720   case 102: return createRegOperand(FLAT_SCR_LO);
721   case 103: return createRegOperand(FLAT_SCR_HI);
722   case 104: return createRegOperand(XNACK_MASK_LO);
723   case 105: return createRegOperand(XNACK_MASK_HI);
724   case 106: return createRegOperand(VCC_LO);
725   case 107: return createRegOperand(VCC_HI);
726   case 108: assert(!isGFX9()); return createRegOperand(TBA_LO);
727   case 109: assert(!isGFX9()); return createRegOperand(TBA_HI);
728   case 110: assert(!isGFX9()); return createRegOperand(TMA_LO);
729   case 111: assert(!isGFX9()); return createRegOperand(TMA_HI);
730   case 124: return createRegOperand(M0);
731   case 126: return createRegOperand(EXEC_LO);
732   case 127: return createRegOperand(EXEC_HI);
733   case 235: return createRegOperand(SRC_SHARED_BASE);
734   case 236: return createRegOperand(SRC_SHARED_LIMIT);
735   case 237: return createRegOperand(SRC_PRIVATE_BASE);
736   case 238: return createRegOperand(SRC_PRIVATE_LIMIT);
737     // TODO: SRC_POPS_EXITING_WAVE_ID
738     // ToDo: no support for vccz register
739   case 251: break;
740     // ToDo: no support for execz register
741   case 252: break;
742   case 253: return createRegOperand(SCC);
743   default: break;
744   }
745   return errOperand(Val, "unknown operand encoding " + Twine(Val));
746 }
747 
748 MCOperand AMDGPUDisassembler::decodeSpecialReg64(unsigned Val) const {
749   using namespace AMDGPU;
750 
751   switch (Val) {
752   case 102: return createRegOperand(FLAT_SCR);
753   case 104: return createRegOperand(XNACK_MASK);
754   case 106: return createRegOperand(VCC);
755   case 108: assert(!isGFX9()); return createRegOperand(TBA);
756   case 110: assert(!isGFX9()); return createRegOperand(TMA);
757   case 126: return createRegOperand(EXEC);
758   default: break;
759   }
760   return errOperand(Val, "unknown operand encoding " + Twine(Val));
761 }
762 
763 MCOperand AMDGPUDisassembler::decodeSDWASrc(const OpWidthTy Width,
764                                             const unsigned Val) const {
765   using namespace AMDGPU::SDWA;
766   using namespace AMDGPU::EncValues;
767 
768   if (STI.getFeatureBits()[AMDGPU::FeatureGFX9]) {
769     // XXX: static_cast<int> is needed to avoid stupid warning:
770     // compare with unsigned is always true
771     if (SDWA9EncValues::SRC_VGPR_MIN <= static_cast<int>(Val) &&
772         Val <= SDWA9EncValues::SRC_VGPR_MAX) {
773       return createRegOperand(getVgprClassId(Width),
774                               Val - SDWA9EncValues::SRC_VGPR_MIN);
775     }
776     if (SDWA9EncValues::SRC_SGPR_MIN <= Val &&
777         Val <= SDWA9EncValues::SRC_SGPR_MAX) {
778       return createSRegOperand(getSgprClassId(Width),
779                                Val - SDWA9EncValues::SRC_SGPR_MIN);
780     }
781     if (SDWA9EncValues::SRC_TTMP_MIN <= Val &&
782         Val <= SDWA9EncValues::SRC_TTMP_MAX) {
783       return createSRegOperand(getTtmpClassId(Width),
784                                Val - SDWA9EncValues::SRC_TTMP_MIN);
785     }
786 
787     const unsigned SVal = Val - SDWA9EncValues::SRC_SGPR_MIN;
788 
789     if (INLINE_INTEGER_C_MIN <= SVal && SVal <= INLINE_INTEGER_C_MAX)
790       return decodeIntImmed(SVal);
791 
792     if (INLINE_FLOATING_C_MIN <= SVal && SVal <= INLINE_FLOATING_C_MAX)
793       return decodeFPImmed(Width, SVal);
794 
795     return decodeSpecialReg32(SVal);
796   } else if (STI.getFeatureBits()[AMDGPU::FeatureVolcanicIslands]) {
797     return createRegOperand(getVgprClassId(Width), Val);
798   }
799   llvm_unreachable("unsupported target");
800 }
801 
802 MCOperand AMDGPUDisassembler::decodeSDWASrc16(unsigned Val) const {
803   return decodeSDWASrc(OPW16, Val);
804 }
805 
806 MCOperand AMDGPUDisassembler::decodeSDWASrc32(unsigned Val) const {
807   return decodeSDWASrc(OPW32, Val);
808 }
809 
810 MCOperand AMDGPUDisassembler::decodeSDWAVopcDst(unsigned Val) const {
811   using namespace AMDGPU::SDWA;
812 
813   assert(STI.getFeatureBits()[AMDGPU::FeatureGFX9] &&
814          "SDWAVopcDst should be present only on GFX9");
815   if (Val & SDWA9EncValues::VOPC_DST_VCC_MASK) {
816     Val &= SDWA9EncValues::VOPC_DST_SGPR_MASK;
817 
818     int TTmpIdx = getTTmpIdx(Val);
819     if (TTmpIdx >= 0) {
820       return createSRegOperand(getTtmpClassId(OPW64), TTmpIdx);
821     } else if (Val > AMDGPU::EncValues::SGPR_MAX) {
822       return decodeSpecialReg64(Val);
823     } else {
824       return createSRegOperand(getSgprClassId(OPW64), Val);
825     }
826   } else {
827     return createRegOperand(AMDGPU::VCC);
828   }
829 }
830 
831 bool AMDGPUDisassembler::isVI() const {
832   return STI.getFeatureBits()[AMDGPU::FeatureVolcanicIslands];
833 }
834 
835 bool AMDGPUDisassembler::isGFX9() const {
836   return STI.getFeatureBits()[AMDGPU::FeatureGFX9];
837 }
838 
839 //===----------------------------------------------------------------------===//
840 // AMDGPUSymbolizer
841 //===----------------------------------------------------------------------===//
842 
843 // Try to find symbol name for specified label
844 bool AMDGPUSymbolizer::tryAddingSymbolicOperand(MCInst &Inst,
845                                 raw_ostream &/*cStream*/, int64_t Value,
846                                 uint64_t /*Address*/, bool IsBranch,
847                                 uint64_t /*Offset*/, uint64_t /*InstSize*/) {
848   using SymbolInfoTy = std::tuple<uint64_t, StringRef, uint8_t>;
849   using SectionSymbolsTy = std::vector<SymbolInfoTy>;
850 
851   if (!IsBranch) {
852     return false;
853   }
854 
855   auto *Symbols = static_cast<SectionSymbolsTy *>(DisInfo);
856   auto Result = std::find_if(Symbols->begin(), Symbols->end(),
857                              [Value](const SymbolInfoTy& Val) {
858                                 return std::get<0>(Val) == static_cast<uint64_t>(Value)
859                                     && std::get<2>(Val) == ELF::STT_NOTYPE;
860                              });
861   if (Result != Symbols->end()) {
862     auto *Sym = Ctx.getOrCreateSymbol(std::get<1>(*Result));
863     const auto *Add = MCSymbolRefExpr::create(Sym, Ctx);
864     Inst.addOperand(MCOperand::createExpr(Add));
865     return true;
866   }
867   return false;
868 }
869 
870 void AMDGPUSymbolizer::tryAddingPcLoadReferenceComment(raw_ostream &cStream,
871                                                        int64_t Value,
872                                                        uint64_t Address) {
873   llvm_unreachable("unimplemented");
874 }
875 
876 //===----------------------------------------------------------------------===//
877 // Initialization
878 //===----------------------------------------------------------------------===//
879 
880 static MCSymbolizer *createAMDGPUSymbolizer(const Triple &/*TT*/,
881                               LLVMOpInfoCallback /*GetOpInfo*/,
882                               LLVMSymbolLookupCallback /*SymbolLookUp*/,
883                               void *DisInfo,
884                               MCContext *Ctx,
885                               std::unique_ptr<MCRelocationInfo> &&RelInfo) {
886   return new AMDGPUSymbolizer(*Ctx, std::move(RelInfo), DisInfo);
887 }
888 
889 static MCDisassembler *createAMDGPUDisassembler(const Target &T,
890                                                 const MCSubtargetInfo &STI,
891                                                 MCContext &Ctx) {
892   return new AMDGPUDisassembler(STI, Ctx, T.createMCInstrInfo());
893 }
894 
895 extern "C" void LLVMInitializeAMDGPUDisassembler() {
896   TargetRegistry::RegisterMCDisassembler(getTheGCNTarget(),
897                                          createAMDGPUDisassembler);
898   TargetRegistry::RegisterMCSymbolizer(getTheGCNTarget(),
899                                        createAMDGPUSymbolizer);
900 }
901