xref: /llvm-project/llvm/lib/Target/AMDGPU/Disassembler/AMDGPUDisassembler.cpp (revision 44b30b453743e95d79ba69a7b9155e23ed4595e5)
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 "MCTargetDesc/AMDGPUMCTargetDesc.h"
25 #include "Utils/AMDGPUBaseInfo.h"
26 #include "llvm-c/Disassembler.h"
27 #include "llvm/ADT/APInt.h"
28 #include "llvm/ADT/ArrayRef.h"
29 #include "llvm/ADT/Twine.h"
30 #include "llvm/BinaryFormat/ELF.h"
31 #include "llvm/MC/MCContext.h"
32 #include "llvm/MC/MCDisassembler/MCDisassembler.h"
33 #include "llvm/MC/MCExpr.h"
34 #include "llvm/MC/MCFixedLenDisassembler.h"
35 #include "llvm/MC/MCInst.h"
36 #include "llvm/MC/MCSubtargetInfo.h"
37 #include "llvm/Support/Endian.h"
38 #include "llvm/Support/ErrorHandling.h"
39 #include "llvm/Support/MathExtras.h"
40 #include "llvm/Support/TargetRegistry.h"
41 #include "llvm/Support/raw_ostream.h"
42 #include <algorithm>
43 #include <cassert>
44 #include <cstddef>
45 #include <cstdint>
46 #include <iterator>
47 #include <tuple>
48 #include <vector>
49 
50 using namespace llvm;
51 
52 #define DEBUG_TYPE "amdgpu-disassembler"
53 
54 using DecodeStatus = llvm::MCDisassembler::DecodeStatus;
55 
56 inline static MCDisassembler::DecodeStatus
57 addOperand(MCInst &Inst, const MCOperand& Opnd) {
58   Inst.addOperand(Opnd);
59   return Opnd.isValid() ?
60     MCDisassembler::Success :
61     MCDisassembler::SoftFail;
62 }
63 
64 static int insertNamedMCOperand(MCInst &MI, const MCOperand &Op,
65                                 uint16_t NameIdx) {
66   int OpIdx = AMDGPU::getNamedOperandIdx(MI.getOpcode(), NameIdx);
67   if (OpIdx != -1) {
68     auto I = MI.begin();
69     std::advance(I, OpIdx);
70     MI.insert(I, Op);
71   }
72   return OpIdx;
73 }
74 
75 static DecodeStatus decodeSoppBrTarget(MCInst &Inst, unsigned Imm,
76                                        uint64_t Addr, const void *Decoder) {
77   auto DAsm = static_cast<const AMDGPUDisassembler*>(Decoder);
78 
79   APInt SignedOffset(18, Imm * 4, true);
80   int64_t Offset = (SignedOffset.sext(64) + 4 + Addr).getSExtValue();
81 
82   if (DAsm->tryAddingSymbolicOperand(Inst, Offset, Addr, true, 2, 2))
83     return MCDisassembler::Success;
84   return addOperand(Inst, MCOperand::createImm(Imm));
85 }
86 
87 #define DECODE_OPERAND(StaticDecoderName, DecoderName) \
88 static DecodeStatus StaticDecoderName(MCInst &Inst, \
89                                        unsigned Imm, \
90                                        uint64_t /*Addr*/, \
91                                        const void *Decoder) { \
92   auto DAsm = static_cast<const AMDGPUDisassembler*>(Decoder); \
93   return addOperand(Inst, DAsm->DecoderName(Imm)); \
94 }
95 
96 #define DECODE_OPERAND_REG(RegClass) \
97 DECODE_OPERAND(Decode##RegClass##RegisterClass, decodeOperand_##RegClass)
98 
99 DECODE_OPERAND_REG(VGPR_32)
100 DECODE_OPERAND_REG(VS_32)
101 DECODE_OPERAND_REG(VS_64)
102 DECODE_OPERAND_REG(VS_128)
103 
104 DECODE_OPERAND_REG(VReg_64)
105 DECODE_OPERAND_REG(VReg_96)
106 DECODE_OPERAND_REG(VReg_128)
107 
108 DECODE_OPERAND_REG(SReg_32)
109 DECODE_OPERAND_REG(SReg_32_XM0_XEXEC)
110 DECODE_OPERAND_REG(SReg_32_XEXEC_HI)
111 DECODE_OPERAND_REG(SReg_64)
112 DECODE_OPERAND_REG(SReg_64_XEXEC)
113 DECODE_OPERAND_REG(SReg_128)
114 DECODE_OPERAND_REG(SReg_256)
115 DECODE_OPERAND_REG(SReg_512)
116 
117 static DecodeStatus decodeOperand_VSrc16(MCInst &Inst,
118                                          unsigned Imm,
119                                          uint64_t Addr,
120                                          const void *Decoder) {
121   auto DAsm = static_cast<const AMDGPUDisassembler*>(Decoder);
122   return addOperand(Inst, DAsm->decodeOperand_VSrc16(Imm));
123 }
124 
125 static DecodeStatus decodeOperand_VSrcV216(MCInst &Inst,
126                                          unsigned Imm,
127                                          uint64_t Addr,
128                                          const void *Decoder) {
129   auto DAsm = static_cast<const AMDGPUDisassembler*>(Decoder);
130   return addOperand(Inst, DAsm->decodeOperand_VSrcV216(Imm));
131 }
132 
133 #define DECODE_SDWA(DecName) \
134 DECODE_OPERAND(decodeSDWA##DecName, decodeSDWA##DecName)
135 
136 DECODE_SDWA(Src32)
137 DECODE_SDWA(Src16)
138 DECODE_SDWA(VopcDst)
139 
140 #include "AMDGPUGenDisassemblerTables.inc"
141 
142 //===----------------------------------------------------------------------===//
143 //
144 //===----------------------------------------------------------------------===//
145 
146 template <typename T> static inline T eatBytes(ArrayRef<uint8_t>& Bytes) {
147   assert(Bytes.size() >= sizeof(T));
148   const auto Res = support::endian::read<T, support::endianness::little>(Bytes.data());
149   Bytes = Bytes.slice(sizeof(T));
150   return Res;
151 }
152 
153 DecodeStatus AMDGPUDisassembler::tryDecodeInst(const uint8_t* Table,
154                                                MCInst &MI,
155                                                uint64_t Inst,
156                                                uint64_t Address) const {
157   assert(MI.getOpcode() == 0);
158   assert(MI.getNumOperands() == 0);
159   MCInst TmpInst;
160   HasLiteral = false;
161   const auto SavedBytes = Bytes;
162   if (decodeInstruction(Table, TmpInst, Inst, Address, this, STI)) {
163     MI = TmpInst;
164     return MCDisassembler::Success;
165   }
166   Bytes = SavedBytes;
167   return MCDisassembler::Fail;
168 }
169 
170 DecodeStatus AMDGPUDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
171                                                 ArrayRef<uint8_t> Bytes_,
172                                                 uint64_t Address,
173                                                 raw_ostream &WS,
174                                                 raw_ostream &CS) const {
175   CommentStream = &CS;
176   bool IsSDWA = false;
177 
178   // ToDo: AMDGPUDisassembler supports only VI ISA.
179   if (!STI.getFeatureBits()[AMDGPU::FeatureGCN3Encoding])
180     report_fatal_error("Disassembly not yet supported for subtarget");
181 
182   const unsigned MaxInstBytesNum = (std::min)((size_t)8, Bytes_.size());
183   Bytes = Bytes_.slice(0, MaxInstBytesNum);
184 
185   DecodeStatus Res = MCDisassembler::Fail;
186   do {
187     // ToDo: better to switch encoding length using some bit predicate
188     // but it is unknown yet, so try all we can
189 
190     // Try to decode DPP and SDWA first to solve conflict with VOP1 and VOP2
191     // encodings
192     if (Bytes.size() >= 8) {
193       const uint64_t QW = eatBytes<uint64_t>(Bytes);
194       Res = tryDecodeInst(DecoderTableDPP64, MI, QW, Address);
195       if (Res) break;
196 
197       Res = tryDecodeInst(DecoderTableSDWA64, MI, QW, Address);
198       if (Res) { IsSDWA = true;  break; }
199 
200       Res = tryDecodeInst(DecoderTableSDWA964, MI, QW, Address);
201       if (Res) { IsSDWA = true;  break; }
202 
203       if (STI.getFeatureBits()[AMDGPU::FeatureUnpackedD16VMem]) {
204         Res = tryDecodeInst(DecoderTableGFX80_UNPACKED64, MI, QW, Address);
205         if (Res)
206           break;
207       }
208 
209       // Some GFX9 subtargets repurposed the v_mad_mix_f32, v_mad_mixlo_f16 and
210       // v_mad_mixhi_f16 for FMA variants. Try to decode using this special
211       // table first so we print the correct name.
212       if (STI.getFeatureBits()[AMDGPU::FeatureFmaMixInsts]) {
213         Res = tryDecodeInst(DecoderTableGFX9_DL64, MI, QW, Address);
214         if (Res)
215           break;
216       }
217     }
218 
219     // Reinitialize Bytes as DPP64 could have eaten too much
220     Bytes = Bytes_.slice(0, MaxInstBytesNum);
221 
222     // Try decode 32-bit instruction
223     if (Bytes.size() < 4) break;
224     const uint32_t DW = eatBytes<uint32_t>(Bytes);
225     Res = tryDecodeInst(DecoderTableVI32, MI, DW, Address);
226     if (Res) break;
227 
228     Res = tryDecodeInst(DecoderTableAMDGPU32, MI, DW, Address);
229     if (Res) break;
230 
231     Res = tryDecodeInst(DecoderTableGFX932, MI, DW, Address);
232     if (Res) break;
233 
234     if (Bytes.size() < 4) break;
235     const uint64_t QW = ((uint64_t)eatBytes<uint32_t>(Bytes) << 32) | DW;
236     Res = tryDecodeInst(DecoderTableVI64, MI, QW, Address);
237     if (Res) break;
238 
239     Res = tryDecodeInst(DecoderTableAMDGPU64, MI, QW, Address);
240     if (Res) break;
241 
242     Res = tryDecodeInst(DecoderTableGFX964, MI, QW, Address);
243   } while (false);
244 
245   if (Res && (MI.getOpcode() == AMDGPU::V_MAC_F32_e64_vi ||
246               MI.getOpcode() == AMDGPU::V_MAC_F32_e64_si ||
247               MI.getOpcode() == AMDGPU::V_MAC_F16_e64_vi ||
248               MI.getOpcode() == AMDGPU::V_FMAC_F32_e64_vi)) {
249     // Insert dummy unused src2_modifiers.
250     insertNamedMCOperand(MI, MCOperand::createImm(0),
251                          AMDGPU::OpName::src2_modifiers);
252   }
253 
254   if (Res && (MCII->get(MI.getOpcode()).TSFlags & SIInstrFlags::MIMG)) {
255     Res = convertMIMGInst(MI);
256   }
257 
258   if (Res && IsSDWA)
259     Res = convertSDWAInst(MI);
260 
261   // if the opcode was not recognized we'll assume a Size of 4 bytes
262   // (unless there are fewer bytes left)
263   Size = Res ? (MaxInstBytesNum - Bytes.size())
264              : std::min((size_t)4, Bytes_.size());
265   return Res;
266 }
267 
268 DecodeStatus AMDGPUDisassembler::convertSDWAInst(MCInst &MI) const {
269   if (STI.getFeatureBits()[AMDGPU::FeatureGFX9]) {
270     if (AMDGPU::getNamedOperandIdx(MI.getOpcode(), AMDGPU::OpName::sdst) != -1)
271       // VOPC - insert clamp
272       insertNamedMCOperand(MI, MCOperand::createImm(0), AMDGPU::OpName::clamp);
273   } else if (STI.getFeatureBits()[AMDGPU::FeatureVolcanicIslands]) {
274     int SDst = AMDGPU::getNamedOperandIdx(MI.getOpcode(), AMDGPU::OpName::sdst);
275     if (SDst != -1) {
276       // VOPC - insert VCC register as sdst
277       insertNamedMCOperand(MI, createRegOperand(AMDGPU::VCC),
278                            AMDGPU::OpName::sdst);
279     } else {
280       // VOP1/2 - insert omod if present in instruction
281       insertNamedMCOperand(MI, MCOperand::createImm(0), AMDGPU::OpName::omod);
282     }
283   }
284   return MCDisassembler::Success;
285 }
286 
287 // Note that MIMG format provides no information about VADDR size.
288 // Consequently, decoded instructions always show address
289 // as if it has 1 dword, which could be not really so.
290 DecodeStatus AMDGPUDisassembler::convertMIMGInst(MCInst &MI) const {
291 
292   if (MCII->get(MI.getOpcode()).TSFlags & SIInstrFlags::Gather4) {
293     return MCDisassembler::Success;
294   }
295 
296   int VDstIdx = AMDGPU::getNamedOperandIdx(MI.getOpcode(),
297                                            AMDGPU::OpName::vdst);
298 
299   int VDataIdx = AMDGPU::getNamedOperandIdx(MI.getOpcode(),
300                                             AMDGPU::OpName::vdata);
301 
302   int DMaskIdx = AMDGPU::getNamedOperandIdx(MI.getOpcode(),
303                                             AMDGPU::OpName::dmask);
304 
305   int TFEIdx   = AMDGPU::getNamedOperandIdx(MI.getOpcode(),
306                                             AMDGPU::OpName::tfe);
307 
308   assert(VDataIdx != -1);
309   assert(DMaskIdx != -1);
310   assert(TFEIdx != -1);
311 
312   bool IsAtomic = (VDstIdx != -1);
313 
314   unsigned DMask = MI.getOperand(DMaskIdx).getImm() & 0xf;
315   if (DMask == 0)
316     return MCDisassembler::Success;
317 
318   unsigned DstSize = countPopulation(DMask);
319   if (DstSize == 1)
320     return MCDisassembler::Success;
321 
322   bool D16 = MCII->get(MI.getOpcode()).TSFlags & SIInstrFlags::D16;
323   if (D16 && AMDGPU::hasPackedD16(STI)) {
324     DstSize = (DstSize + 1) / 2;
325   }
326 
327   // FIXME: Add tfe support
328   if (MI.getOperand(TFEIdx).getImm())
329     return MCDisassembler::Success;
330 
331   int NewOpcode = -1;
332 
333   if (IsAtomic) {
334     if (DMask == 0x1 || DMask == 0x3 || DMask == 0xF) {
335       NewOpcode = AMDGPU::getMaskedMIMGAtomicOp(*MCII, MI.getOpcode(), DstSize);
336     }
337     if (NewOpcode == -1) return MCDisassembler::Success;
338   } else {
339     NewOpcode = AMDGPU::getMaskedMIMGOp(*MCII, MI.getOpcode(), DstSize);
340     assert(NewOpcode != -1 && "could not find matching mimg channel instruction");
341   }
342 
343   auto RCID = MCII->get(NewOpcode).OpInfo[VDataIdx].RegClass;
344 
345   // Get first subregister of VData
346   unsigned Vdata0 = MI.getOperand(VDataIdx).getReg();
347   unsigned VdataSub0 = MRI.getSubReg(Vdata0, AMDGPU::sub0);
348   Vdata0 = (VdataSub0 != 0)? VdataSub0 : Vdata0;
349 
350   // Widen the register to the correct number of enabled channels.
351   auto NewVdata = MRI.getMatchingSuperReg(Vdata0, AMDGPU::sub0,
352                                           &MRI.getRegClass(RCID));
353   if (NewVdata == AMDGPU::NoRegister) {
354     // It's possible to encode this such that the low register + enabled
355     // components exceeds the register count.
356     return MCDisassembler::Success;
357   }
358 
359   MI.setOpcode(NewOpcode);
360   // vaddr will be always appear as a single VGPR. This will look different than
361   // how it is usually emitted because the number of register components is not
362   // in the instruction encoding.
363   MI.getOperand(VDataIdx) = MCOperand::createReg(NewVdata);
364 
365   if (IsAtomic) {
366     // Atomic operations have an additional operand (a copy of data)
367     MI.getOperand(VDstIdx) = MCOperand::createReg(NewVdata);
368   }
369 
370   return MCDisassembler::Success;
371 }
372 
373 const char* AMDGPUDisassembler::getRegClassName(unsigned RegClassID) const {
374   return getContext().getRegisterInfo()->
375     getRegClassName(&AMDGPUMCRegisterClasses[RegClassID]);
376 }
377 
378 inline
379 MCOperand AMDGPUDisassembler::errOperand(unsigned V,
380                                          const Twine& ErrMsg) const {
381   *CommentStream << "Error: " + ErrMsg;
382 
383   // ToDo: add support for error operands to MCInst.h
384   // return MCOperand::createError(V);
385   return MCOperand();
386 }
387 
388 inline
389 MCOperand AMDGPUDisassembler::createRegOperand(unsigned int RegId) const {
390   return MCOperand::createReg(AMDGPU::getMCReg(RegId, STI));
391 }
392 
393 inline
394 MCOperand AMDGPUDisassembler::createRegOperand(unsigned RegClassID,
395                                                unsigned Val) const {
396   const auto& RegCl = AMDGPUMCRegisterClasses[RegClassID];
397   if (Val >= RegCl.getNumRegs())
398     return errOperand(Val, Twine(getRegClassName(RegClassID)) +
399                            ": unknown register " + Twine(Val));
400   return createRegOperand(RegCl.getRegister(Val));
401 }
402 
403 inline
404 MCOperand AMDGPUDisassembler::createSRegOperand(unsigned SRegClassID,
405                                                 unsigned Val) const {
406   // ToDo: SI/CI have 104 SGPRs, VI - 102
407   // Valery: here we accepting as much as we can, let assembler sort it out
408   int shift = 0;
409   switch (SRegClassID) {
410   case AMDGPU::SGPR_32RegClassID:
411   case AMDGPU::TTMP_32RegClassID:
412     break;
413   case AMDGPU::SGPR_64RegClassID:
414   case AMDGPU::TTMP_64RegClassID:
415     shift = 1;
416     break;
417   case AMDGPU::SGPR_128RegClassID:
418   case AMDGPU::TTMP_128RegClassID:
419   // ToDo: unclear if s[100:104] is available on VI. Can we use VCC as SGPR in
420   // this bundle?
421   case AMDGPU::SGPR_256RegClassID:
422   case AMDGPU::TTMP_256RegClassID:
423     // ToDo: unclear if s[96:104] is available on VI. Can we use VCC as SGPR in
424   // this bundle?
425   case AMDGPU::SGPR_512RegClassID:
426   case AMDGPU::TTMP_512RegClassID:
427     shift = 2;
428     break;
429   // ToDo: unclear if s[88:104] is available on VI. Can we use VCC as SGPR in
430   // this bundle?
431   default:
432     llvm_unreachable("unhandled register class");
433   }
434 
435   if (Val % (1 << shift)) {
436     *CommentStream << "Warning: " << getRegClassName(SRegClassID)
437                    << ": scalar reg isn't aligned " << Val;
438   }
439 
440   return createRegOperand(SRegClassID, Val >> shift);
441 }
442 
443 MCOperand AMDGPUDisassembler::decodeOperand_VS_32(unsigned Val) const {
444   return decodeSrcOp(OPW32, Val);
445 }
446 
447 MCOperand AMDGPUDisassembler::decodeOperand_VS_64(unsigned Val) const {
448   return decodeSrcOp(OPW64, Val);
449 }
450 
451 MCOperand AMDGPUDisassembler::decodeOperand_VS_128(unsigned Val) const {
452   return decodeSrcOp(OPW128, Val);
453 }
454 
455 MCOperand AMDGPUDisassembler::decodeOperand_VSrc16(unsigned Val) const {
456   return decodeSrcOp(OPW16, Val);
457 }
458 
459 MCOperand AMDGPUDisassembler::decodeOperand_VSrcV216(unsigned Val) const {
460   return decodeSrcOp(OPWV216, Val);
461 }
462 
463 MCOperand AMDGPUDisassembler::decodeOperand_VGPR_32(unsigned Val) const {
464   // Some instructions have operand restrictions beyond what the encoding
465   // allows. Some ordinarily VSrc_32 operands are VGPR_32, so clear the extra
466   // high bit.
467   Val &= 255;
468 
469   return createRegOperand(AMDGPU::VGPR_32RegClassID, Val);
470 }
471 
472 MCOperand AMDGPUDisassembler::decodeOperand_VReg_64(unsigned Val) const {
473   return createRegOperand(AMDGPU::VReg_64RegClassID, Val);
474 }
475 
476 MCOperand AMDGPUDisassembler::decodeOperand_VReg_96(unsigned Val) const {
477   return createRegOperand(AMDGPU::VReg_96RegClassID, Val);
478 }
479 
480 MCOperand AMDGPUDisassembler::decodeOperand_VReg_128(unsigned Val) const {
481   return createRegOperand(AMDGPU::VReg_128RegClassID, Val);
482 }
483 
484 MCOperand AMDGPUDisassembler::decodeOperand_SReg_32(unsigned Val) const {
485   // table-gen generated disassembler doesn't care about operand types
486   // leaving only registry class so SSrc_32 operand turns into SReg_32
487   // and therefore we accept immediates and literals here as well
488   return decodeSrcOp(OPW32, Val);
489 }
490 
491 MCOperand AMDGPUDisassembler::decodeOperand_SReg_32_XM0_XEXEC(
492   unsigned Val) const {
493   // SReg_32_XM0 is SReg_32 without M0 or EXEC_LO/EXEC_HI
494   return decodeOperand_SReg_32(Val);
495 }
496 
497 MCOperand AMDGPUDisassembler::decodeOperand_SReg_32_XEXEC_HI(
498   unsigned Val) const {
499   // SReg_32_XM0 is SReg_32 without EXEC_HI
500   return decodeOperand_SReg_32(Val);
501 }
502 
503 MCOperand AMDGPUDisassembler::decodeOperand_SReg_64(unsigned Val) const {
504   return decodeSrcOp(OPW64, Val);
505 }
506 
507 MCOperand AMDGPUDisassembler::decodeOperand_SReg_64_XEXEC(unsigned Val) const {
508   return decodeSrcOp(OPW64, Val);
509 }
510 
511 MCOperand AMDGPUDisassembler::decodeOperand_SReg_128(unsigned Val) const {
512   return decodeSrcOp(OPW128, Val);
513 }
514 
515 MCOperand AMDGPUDisassembler::decodeOperand_SReg_256(unsigned Val) const {
516   return decodeDstOp(OPW256, Val);
517 }
518 
519 MCOperand AMDGPUDisassembler::decodeOperand_SReg_512(unsigned Val) const {
520   return decodeDstOp(OPW512, Val);
521 }
522 
523 MCOperand AMDGPUDisassembler::decodeLiteralConstant() const {
524   // For now all literal constants are supposed to be unsigned integer
525   // ToDo: deal with signed/unsigned 64-bit integer constants
526   // ToDo: deal with float/double constants
527   if (!HasLiteral) {
528     if (Bytes.size() < 4) {
529       return errOperand(0, "cannot read literal, inst bytes left " +
530                         Twine(Bytes.size()));
531     }
532     HasLiteral = true;
533     Literal = eatBytes<uint32_t>(Bytes);
534   }
535   return MCOperand::createImm(Literal);
536 }
537 
538 MCOperand AMDGPUDisassembler::decodeIntImmed(unsigned Imm) {
539   using namespace AMDGPU::EncValues;
540 
541   assert(Imm >= INLINE_INTEGER_C_MIN && Imm <= INLINE_INTEGER_C_MAX);
542   return MCOperand::createImm((Imm <= INLINE_INTEGER_C_POSITIVE_MAX) ?
543     (static_cast<int64_t>(Imm) - INLINE_INTEGER_C_MIN) :
544     (INLINE_INTEGER_C_POSITIVE_MAX - static_cast<int64_t>(Imm)));
545       // Cast prevents negative overflow.
546 }
547 
548 static int64_t getInlineImmVal32(unsigned Imm) {
549   switch (Imm) {
550   case 240:
551     return FloatToBits(0.5f);
552   case 241:
553     return FloatToBits(-0.5f);
554   case 242:
555     return FloatToBits(1.0f);
556   case 243:
557     return FloatToBits(-1.0f);
558   case 244:
559     return FloatToBits(2.0f);
560   case 245:
561     return FloatToBits(-2.0f);
562   case 246:
563     return FloatToBits(4.0f);
564   case 247:
565     return FloatToBits(-4.0f);
566   case 248: // 1 / (2 * PI)
567     return 0x3e22f983;
568   default:
569     llvm_unreachable("invalid fp inline imm");
570   }
571 }
572 
573 static int64_t getInlineImmVal64(unsigned Imm) {
574   switch (Imm) {
575   case 240:
576     return DoubleToBits(0.5);
577   case 241:
578     return DoubleToBits(-0.5);
579   case 242:
580     return DoubleToBits(1.0);
581   case 243:
582     return DoubleToBits(-1.0);
583   case 244:
584     return DoubleToBits(2.0);
585   case 245:
586     return DoubleToBits(-2.0);
587   case 246:
588     return DoubleToBits(4.0);
589   case 247:
590     return DoubleToBits(-4.0);
591   case 248: // 1 / (2 * PI)
592     return 0x3fc45f306dc9c882;
593   default:
594     llvm_unreachable("invalid fp inline imm");
595   }
596 }
597 
598 static int64_t getInlineImmVal16(unsigned Imm) {
599   switch (Imm) {
600   case 240:
601     return 0x3800;
602   case 241:
603     return 0xB800;
604   case 242:
605     return 0x3C00;
606   case 243:
607     return 0xBC00;
608   case 244:
609     return 0x4000;
610   case 245:
611     return 0xC000;
612   case 246:
613     return 0x4400;
614   case 247:
615     return 0xC400;
616   case 248: // 1 / (2 * PI)
617     return 0x3118;
618   default:
619     llvm_unreachable("invalid fp inline imm");
620   }
621 }
622 
623 MCOperand AMDGPUDisassembler::decodeFPImmed(OpWidthTy Width, unsigned Imm) {
624   assert(Imm >= AMDGPU::EncValues::INLINE_FLOATING_C_MIN
625       && Imm <= AMDGPU::EncValues::INLINE_FLOATING_C_MAX);
626 
627   // ToDo: case 248: 1/(2*PI) - is allowed only on VI
628   switch (Width) {
629   case OPW32:
630     return MCOperand::createImm(getInlineImmVal32(Imm));
631   case OPW64:
632     return MCOperand::createImm(getInlineImmVal64(Imm));
633   case OPW16:
634   case OPWV216:
635     return MCOperand::createImm(getInlineImmVal16(Imm));
636   default:
637     llvm_unreachable("implement me");
638   }
639 }
640 
641 unsigned AMDGPUDisassembler::getVgprClassId(const OpWidthTy Width) const {
642   using namespace AMDGPU;
643 
644   assert(OPW_FIRST_ <= Width && Width < OPW_LAST_);
645   switch (Width) {
646   default: // fall
647   case OPW32:
648   case OPW16:
649   case OPWV216:
650     return VGPR_32RegClassID;
651   case OPW64: return VReg_64RegClassID;
652   case OPW128: return VReg_128RegClassID;
653   }
654 }
655 
656 unsigned AMDGPUDisassembler::getSgprClassId(const OpWidthTy Width) const {
657   using namespace AMDGPU;
658 
659   assert(OPW_FIRST_ <= Width && Width < OPW_LAST_);
660   switch (Width) {
661   default: // fall
662   case OPW32:
663   case OPW16:
664   case OPWV216:
665     return SGPR_32RegClassID;
666   case OPW64: return SGPR_64RegClassID;
667   case OPW128: return SGPR_128RegClassID;
668   case OPW256: return SGPR_256RegClassID;
669   case OPW512: return SGPR_512RegClassID;
670   }
671 }
672 
673 unsigned AMDGPUDisassembler::getTtmpClassId(const OpWidthTy Width) const {
674   using namespace AMDGPU;
675 
676   assert(OPW_FIRST_ <= Width && Width < OPW_LAST_);
677   switch (Width) {
678   default: // fall
679   case OPW32:
680   case OPW16:
681   case OPWV216:
682     return TTMP_32RegClassID;
683   case OPW64: return TTMP_64RegClassID;
684   case OPW128: return TTMP_128RegClassID;
685   case OPW256: return TTMP_256RegClassID;
686   case OPW512: return TTMP_512RegClassID;
687   }
688 }
689 
690 int AMDGPUDisassembler::getTTmpIdx(unsigned Val) const {
691   using namespace AMDGPU::EncValues;
692 
693   unsigned TTmpMin = isGFX9() ? TTMP_GFX9_MIN : TTMP_VI_MIN;
694   unsigned TTmpMax = isGFX9() ? TTMP_GFX9_MAX : TTMP_VI_MAX;
695 
696   return (TTmpMin <= Val && Val <= TTmpMax)? Val - TTmpMin : -1;
697 }
698 
699 MCOperand AMDGPUDisassembler::decodeSrcOp(const OpWidthTy Width, unsigned Val) const {
700   using namespace AMDGPU::EncValues;
701 
702   assert(Val < 512); // enum9
703 
704   if (VGPR_MIN <= Val && Val <= VGPR_MAX) {
705     return createRegOperand(getVgprClassId(Width), Val - VGPR_MIN);
706   }
707   if (Val <= SGPR_MAX) {
708     assert(SGPR_MIN == 0); // "SGPR_MIN <= Val" is always true and causes compilation warning.
709     return createSRegOperand(getSgprClassId(Width), Val - SGPR_MIN);
710   }
711 
712   int TTmpIdx = getTTmpIdx(Val);
713   if (TTmpIdx >= 0) {
714     return createSRegOperand(getTtmpClassId(Width), TTmpIdx);
715   }
716 
717   if (INLINE_INTEGER_C_MIN <= Val && Val <= INLINE_INTEGER_C_MAX)
718     return decodeIntImmed(Val);
719 
720   if (INLINE_FLOATING_C_MIN <= Val && Val <= INLINE_FLOATING_C_MAX)
721     return decodeFPImmed(Width, Val);
722 
723   if (Val == LITERAL_CONST)
724     return decodeLiteralConstant();
725 
726   switch (Width) {
727   case OPW32:
728   case OPW16:
729   case OPWV216:
730     return decodeSpecialReg32(Val);
731   case OPW64:
732     return decodeSpecialReg64(Val);
733   default:
734     llvm_unreachable("unexpected immediate type");
735   }
736 }
737 
738 MCOperand AMDGPUDisassembler::decodeDstOp(const OpWidthTy Width, unsigned Val) const {
739   using namespace AMDGPU::EncValues;
740 
741   assert(Val < 128);
742   assert(Width == OPW256 || Width == OPW512);
743 
744   if (Val <= SGPR_MAX) {
745     assert(SGPR_MIN == 0); // "SGPR_MIN <= Val" is always true and causes compilation warning.
746     return createSRegOperand(getSgprClassId(Width), Val - SGPR_MIN);
747   }
748 
749   int TTmpIdx = getTTmpIdx(Val);
750   if (TTmpIdx >= 0) {
751     return createSRegOperand(getTtmpClassId(Width), TTmpIdx);
752   }
753 
754   llvm_unreachable("unknown dst register");
755 }
756 
757 MCOperand AMDGPUDisassembler::decodeSpecialReg32(unsigned Val) const {
758   using namespace AMDGPU;
759 
760   switch (Val) {
761   case 102: return createRegOperand(FLAT_SCR_LO);
762   case 103: return createRegOperand(FLAT_SCR_HI);
763   case 104: return createRegOperand(XNACK_MASK_LO);
764   case 105: return createRegOperand(XNACK_MASK_HI);
765   case 106: return createRegOperand(VCC_LO);
766   case 107: return createRegOperand(VCC_HI);
767   case 108: assert(!isGFX9()); return createRegOperand(TBA_LO);
768   case 109: assert(!isGFX9()); return createRegOperand(TBA_HI);
769   case 110: assert(!isGFX9()); return createRegOperand(TMA_LO);
770   case 111: assert(!isGFX9()); return createRegOperand(TMA_HI);
771   case 124: return createRegOperand(M0);
772   case 126: return createRegOperand(EXEC_LO);
773   case 127: return createRegOperand(EXEC_HI);
774   case 235: return createRegOperand(SRC_SHARED_BASE);
775   case 236: return createRegOperand(SRC_SHARED_LIMIT);
776   case 237: return createRegOperand(SRC_PRIVATE_BASE);
777   case 238: return createRegOperand(SRC_PRIVATE_LIMIT);
778     // TODO: SRC_POPS_EXITING_WAVE_ID
779     // ToDo: no support for vccz register
780   case 251: break;
781     // ToDo: no support for execz register
782   case 252: break;
783   case 253: return createRegOperand(SCC);
784   default: break;
785   }
786   return errOperand(Val, "unknown operand encoding " + Twine(Val));
787 }
788 
789 MCOperand AMDGPUDisassembler::decodeSpecialReg64(unsigned Val) const {
790   using namespace AMDGPU;
791 
792   switch (Val) {
793   case 102: return createRegOperand(FLAT_SCR);
794   case 104: return createRegOperand(XNACK_MASK);
795   case 106: return createRegOperand(VCC);
796   case 108: assert(!isGFX9()); return createRegOperand(TBA);
797   case 110: assert(!isGFX9()); return createRegOperand(TMA);
798   case 126: return createRegOperand(EXEC);
799   default: break;
800   }
801   return errOperand(Val, "unknown operand encoding " + Twine(Val));
802 }
803 
804 MCOperand AMDGPUDisassembler::decodeSDWASrc(const OpWidthTy Width,
805                                             const unsigned Val) const {
806   using namespace AMDGPU::SDWA;
807   using namespace AMDGPU::EncValues;
808 
809   if (STI.getFeatureBits()[AMDGPU::FeatureGFX9]) {
810     // XXX: static_cast<int> is needed to avoid stupid warning:
811     // compare with unsigned is always true
812     if (SDWA9EncValues::SRC_VGPR_MIN <= static_cast<int>(Val) &&
813         Val <= SDWA9EncValues::SRC_VGPR_MAX) {
814       return createRegOperand(getVgprClassId(Width),
815                               Val - SDWA9EncValues::SRC_VGPR_MIN);
816     }
817     if (SDWA9EncValues::SRC_SGPR_MIN <= Val &&
818         Val <= SDWA9EncValues::SRC_SGPR_MAX) {
819       return createSRegOperand(getSgprClassId(Width),
820                                Val - SDWA9EncValues::SRC_SGPR_MIN);
821     }
822     if (SDWA9EncValues::SRC_TTMP_MIN <= Val &&
823         Val <= SDWA9EncValues::SRC_TTMP_MAX) {
824       return createSRegOperand(getTtmpClassId(Width),
825                                Val - SDWA9EncValues::SRC_TTMP_MIN);
826     }
827 
828     const unsigned SVal = Val - SDWA9EncValues::SRC_SGPR_MIN;
829 
830     if (INLINE_INTEGER_C_MIN <= SVal && SVal <= INLINE_INTEGER_C_MAX)
831       return decodeIntImmed(SVal);
832 
833     if (INLINE_FLOATING_C_MIN <= SVal && SVal <= INLINE_FLOATING_C_MAX)
834       return decodeFPImmed(Width, SVal);
835 
836     return decodeSpecialReg32(SVal);
837   } else if (STI.getFeatureBits()[AMDGPU::FeatureVolcanicIslands]) {
838     return createRegOperand(getVgprClassId(Width), Val);
839   }
840   llvm_unreachable("unsupported target");
841 }
842 
843 MCOperand AMDGPUDisassembler::decodeSDWASrc16(unsigned Val) const {
844   return decodeSDWASrc(OPW16, Val);
845 }
846 
847 MCOperand AMDGPUDisassembler::decodeSDWASrc32(unsigned Val) const {
848   return decodeSDWASrc(OPW32, Val);
849 }
850 
851 MCOperand AMDGPUDisassembler::decodeSDWAVopcDst(unsigned Val) const {
852   using namespace AMDGPU::SDWA;
853 
854   assert(STI.getFeatureBits()[AMDGPU::FeatureGFX9] &&
855          "SDWAVopcDst should be present only on GFX9");
856   if (Val & SDWA9EncValues::VOPC_DST_VCC_MASK) {
857     Val &= SDWA9EncValues::VOPC_DST_SGPR_MASK;
858 
859     int TTmpIdx = getTTmpIdx(Val);
860     if (TTmpIdx >= 0) {
861       return createSRegOperand(getTtmpClassId(OPW64), TTmpIdx);
862     } else if (Val > AMDGPU::EncValues::SGPR_MAX) {
863       return decodeSpecialReg64(Val);
864     } else {
865       return createSRegOperand(getSgprClassId(OPW64), Val);
866     }
867   } else {
868     return createRegOperand(AMDGPU::VCC);
869   }
870 }
871 
872 bool AMDGPUDisassembler::isVI() const {
873   return STI.getFeatureBits()[AMDGPU::FeatureVolcanicIslands];
874 }
875 
876 bool AMDGPUDisassembler::isGFX9() const {
877   return STI.getFeatureBits()[AMDGPU::FeatureGFX9];
878 }
879 
880 //===----------------------------------------------------------------------===//
881 // AMDGPUSymbolizer
882 //===----------------------------------------------------------------------===//
883 
884 // Try to find symbol name for specified label
885 bool AMDGPUSymbolizer::tryAddingSymbolicOperand(MCInst &Inst,
886                                 raw_ostream &/*cStream*/, int64_t Value,
887                                 uint64_t /*Address*/, bool IsBranch,
888                                 uint64_t /*Offset*/, uint64_t /*InstSize*/) {
889   using SymbolInfoTy = std::tuple<uint64_t, StringRef, uint8_t>;
890   using SectionSymbolsTy = std::vector<SymbolInfoTy>;
891 
892   if (!IsBranch) {
893     return false;
894   }
895 
896   auto *Symbols = static_cast<SectionSymbolsTy *>(DisInfo);
897   if (!Symbols)
898     return false;
899 
900   auto Result = std::find_if(Symbols->begin(), Symbols->end(),
901                              [Value](const SymbolInfoTy& Val) {
902                                 return std::get<0>(Val) == static_cast<uint64_t>(Value)
903                                     && std::get<2>(Val) == ELF::STT_NOTYPE;
904                              });
905   if (Result != Symbols->end()) {
906     auto *Sym = Ctx.getOrCreateSymbol(std::get<1>(*Result));
907     const auto *Add = MCSymbolRefExpr::create(Sym, Ctx);
908     Inst.addOperand(MCOperand::createExpr(Add));
909     return true;
910   }
911   return false;
912 }
913 
914 void AMDGPUSymbolizer::tryAddingPcLoadReferenceComment(raw_ostream &cStream,
915                                                        int64_t Value,
916                                                        uint64_t Address) {
917   llvm_unreachable("unimplemented");
918 }
919 
920 //===----------------------------------------------------------------------===//
921 // Initialization
922 //===----------------------------------------------------------------------===//
923 
924 static MCSymbolizer *createAMDGPUSymbolizer(const Triple &/*TT*/,
925                               LLVMOpInfoCallback /*GetOpInfo*/,
926                               LLVMSymbolLookupCallback /*SymbolLookUp*/,
927                               void *DisInfo,
928                               MCContext *Ctx,
929                               std::unique_ptr<MCRelocationInfo> &&RelInfo) {
930   return new AMDGPUSymbolizer(*Ctx, std::move(RelInfo), DisInfo);
931 }
932 
933 static MCDisassembler *createAMDGPUDisassembler(const Target &T,
934                                                 const MCSubtargetInfo &STI,
935                                                 MCContext &Ctx) {
936   return new AMDGPUDisassembler(STI, Ctx, T.createMCInstrInfo());
937 }
938 
939 extern "C" void LLVMInitializeAMDGPUDisassembler() {
940   TargetRegistry::RegisterMCDisassembler(getTheGCNTarget(),
941                                          createAMDGPUDisassembler);
942   TargetRegistry::RegisterMCSymbolizer(getTheGCNTarget(),
943                                        createAMDGPUSymbolizer);
944 }
945