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       if (STI.getFeatureBits()[AMDGPU::FeatureUnpackedD16VMem]) {
203         Res = tryDecodeInst(DecoderTableGFX80_UNPACKED64, MI, QW, Address);
204         if (Res) break;
205       }
206     }
207 
208     // Reinitialize Bytes as DPP64 could have eaten too much
209     Bytes = Bytes_.slice(0, MaxInstBytesNum);
210 
211     // Try decode 32-bit instruction
212     if (Bytes.size() < 4) break;
213     const uint32_t DW = eatBytes<uint32_t>(Bytes);
214     Res = tryDecodeInst(DecoderTableVI32, MI, DW, Address);
215     if (Res) break;
216 
217     Res = tryDecodeInst(DecoderTableAMDGPU32, MI, DW, Address);
218     if (Res) break;
219 
220     Res = tryDecodeInst(DecoderTableGFX932, MI, DW, Address);
221     if (Res) break;
222 
223     if (Bytes.size() < 4) break;
224     const uint64_t QW = ((uint64_t)eatBytes<uint32_t>(Bytes) << 32) | DW;
225     Res = tryDecodeInst(DecoderTableVI64, MI, QW, Address);
226     if (Res) break;
227 
228     Res = tryDecodeInst(DecoderTableAMDGPU64, MI, QW, Address);
229     if (Res) break;
230 
231     Res = tryDecodeInst(DecoderTableGFX964, MI, QW, Address);
232   } while (false);
233 
234   if (Res && (MI.getOpcode() == AMDGPU::V_MAC_F32_e64_vi ||
235               MI.getOpcode() == AMDGPU::V_MAC_F32_e64_si ||
236               MI.getOpcode() == AMDGPU::V_MAC_F16_e64_vi)) {
237     // Insert dummy unused src2_modifiers.
238     insertNamedMCOperand(MI, MCOperand::createImm(0),
239                          AMDGPU::OpName::src2_modifiers);
240   }
241 
242   if (Res && (MCII->get(MI.getOpcode()).TSFlags & SIInstrFlags::MIMG)) {
243     Res = convertMIMGInst(MI);
244   }
245 
246   if (Res && IsSDWA)
247     Res = convertSDWAInst(MI);
248 
249   Size = Res ? (MaxInstBytesNum - Bytes.size()) : 0;
250   return Res;
251 }
252 
253 DecodeStatus AMDGPUDisassembler::convertSDWAInst(MCInst &MI) const {
254   if (STI.getFeatureBits()[AMDGPU::FeatureGFX9]) {
255     if (AMDGPU::getNamedOperandIdx(MI.getOpcode(), AMDGPU::OpName::sdst) != -1)
256       // VOPC - insert clamp
257       insertNamedMCOperand(MI, MCOperand::createImm(0), AMDGPU::OpName::clamp);
258   } else if (STI.getFeatureBits()[AMDGPU::FeatureVolcanicIslands]) {
259     int SDst = AMDGPU::getNamedOperandIdx(MI.getOpcode(), AMDGPU::OpName::sdst);
260     if (SDst != -1) {
261       // VOPC - insert VCC register as sdst
262       insertNamedMCOperand(MI, createRegOperand(AMDGPU::VCC),
263                            AMDGPU::OpName::sdst);
264     } else {
265       // VOP1/2 - insert omod if present in instruction
266       insertNamedMCOperand(MI, MCOperand::createImm(0), AMDGPU::OpName::omod);
267     }
268   }
269   return MCDisassembler::Success;
270 }
271 
272 DecodeStatus AMDGPUDisassembler::convertMIMGInst(MCInst &MI) const {
273   int VDstIdx = AMDGPU::getNamedOperandIdx(MI.getOpcode(),
274                                            AMDGPU::OpName::vdst);
275 
276   int VDataIdx = AMDGPU::getNamedOperandIdx(MI.getOpcode(),
277                                             AMDGPU::OpName::vdata);
278 
279   int DMaskIdx = AMDGPU::getNamedOperandIdx(MI.getOpcode(),
280                                             AMDGPU::OpName::dmask);
281 
282   assert(VDataIdx != -1);
283   assert(DMaskIdx != -1);
284 
285   bool isAtomic = (VDstIdx != -1);
286 
287   unsigned DMask = MI.getOperand(DMaskIdx).getImm() & 0xf;
288   if (DMask == 0)
289     return MCDisassembler::Success;
290 
291   unsigned ChannelCount = countPopulation(DMask);
292   if (ChannelCount == 1)
293     return MCDisassembler::Success;
294 
295   int NewOpcode = -1;
296 
297   if (isAtomic) {
298     if (DMask == 0x1 || DMask == 0x3 || DMask == 0xF) {
299       NewOpcode = AMDGPU::getMaskedMIMGAtomicOp(*MCII, MI.getOpcode(), ChannelCount);
300     }
301     if (NewOpcode == -1) return MCDisassembler::Success;
302   } else {
303     NewOpcode = AMDGPU::getMaskedMIMGOp(*MCII, MI.getOpcode(), ChannelCount);
304     assert(NewOpcode != -1 && "could not find matching mimg channel instruction");
305   }
306 
307   auto RCID = MCII->get(NewOpcode).OpInfo[VDataIdx].RegClass;
308 
309   // Get first subregister of VData
310   unsigned Vdata0 = MI.getOperand(VDataIdx).getReg();
311   unsigned VdataSub0 = MRI.getSubReg(Vdata0, AMDGPU::sub0);
312   Vdata0 = (VdataSub0 != 0)? VdataSub0 : Vdata0;
313 
314   // Widen the register to the correct number of enabled channels.
315   auto NewVdata = MRI.getMatchingSuperReg(Vdata0, AMDGPU::sub0,
316                                           &MRI.getRegClass(RCID));
317   if (NewVdata == AMDGPU::NoRegister) {
318     // It's possible to encode this such that the low register + enabled
319     // components exceeds the register count.
320     return MCDisassembler::Success;
321   }
322 
323   MI.setOpcode(NewOpcode);
324   // vaddr will be always appear as a single VGPR. This will look different than
325   // how it is usually emitted because the number of register components is not
326   // in the instruction encoding.
327   MI.getOperand(VDataIdx) = MCOperand::createReg(NewVdata);
328 
329   if (isAtomic) {
330     // Atomic operations have an additional operand (a copy of data)
331     MI.getOperand(VDstIdx) = MCOperand::createReg(NewVdata);
332   }
333 
334   return MCDisassembler::Success;
335 }
336 
337 const char* AMDGPUDisassembler::getRegClassName(unsigned RegClassID) const {
338   return getContext().getRegisterInfo()->
339     getRegClassName(&AMDGPUMCRegisterClasses[RegClassID]);
340 }
341 
342 inline
343 MCOperand AMDGPUDisassembler::errOperand(unsigned V,
344                                          const Twine& ErrMsg) const {
345   *CommentStream << "Error: " + ErrMsg;
346 
347   // ToDo: add support for error operands to MCInst.h
348   // return MCOperand::createError(V);
349   return MCOperand();
350 }
351 
352 inline
353 MCOperand AMDGPUDisassembler::createRegOperand(unsigned int RegId) const {
354   return MCOperand::createReg(AMDGPU::getMCReg(RegId, STI));
355 }
356 
357 inline
358 MCOperand AMDGPUDisassembler::createRegOperand(unsigned RegClassID,
359                                                unsigned Val) const {
360   const auto& RegCl = AMDGPUMCRegisterClasses[RegClassID];
361   if (Val >= RegCl.getNumRegs())
362     return errOperand(Val, Twine(getRegClassName(RegClassID)) +
363                            ": unknown register " + Twine(Val));
364   return createRegOperand(RegCl.getRegister(Val));
365 }
366 
367 inline
368 MCOperand AMDGPUDisassembler::createSRegOperand(unsigned SRegClassID,
369                                                 unsigned Val) const {
370   // ToDo: SI/CI have 104 SGPRs, VI - 102
371   // Valery: here we accepting as much as we can, let assembler sort it out
372   int shift = 0;
373   switch (SRegClassID) {
374   case AMDGPU::SGPR_32RegClassID:
375   case AMDGPU::TTMP_32RegClassID:
376     break;
377   case AMDGPU::SGPR_64RegClassID:
378   case AMDGPU::TTMP_64RegClassID:
379     shift = 1;
380     break;
381   case AMDGPU::SGPR_128RegClassID:
382   case AMDGPU::TTMP_128RegClassID:
383   // ToDo: unclear if s[100:104] is available on VI. Can we use VCC as SGPR in
384   // this bundle?
385   case AMDGPU::SGPR_256RegClassID:
386   case AMDGPU::TTMP_256RegClassID:
387     // ToDo: unclear if s[96:104] is available on VI. Can we use VCC as SGPR in
388   // this bundle?
389   case AMDGPU::SGPR_512RegClassID:
390   case AMDGPU::TTMP_512RegClassID:
391     shift = 2;
392     break;
393   // ToDo: unclear if s[88:104] is available on VI. Can we use VCC as SGPR in
394   // this bundle?
395   default:
396     llvm_unreachable("unhandled register class");
397   }
398 
399   if (Val % (1 << shift)) {
400     *CommentStream << "Warning: " << getRegClassName(SRegClassID)
401                    << ": scalar reg isn't aligned " << Val;
402   }
403 
404   return createRegOperand(SRegClassID, Val >> shift);
405 }
406 
407 MCOperand AMDGPUDisassembler::decodeOperand_VS_32(unsigned Val) const {
408   return decodeSrcOp(OPW32, Val);
409 }
410 
411 MCOperand AMDGPUDisassembler::decodeOperand_VS_64(unsigned Val) const {
412   return decodeSrcOp(OPW64, Val);
413 }
414 
415 MCOperand AMDGPUDisassembler::decodeOperand_VS_128(unsigned Val) const {
416   return decodeSrcOp(OPW128, Val);
417 }
418 
419 MCOperand AMDGPUDisassembler::decodeOperand_VSrc16(unsigned Val) const {
420   return decodeSrcOp(OPW16, Val);
421 }
422 
423 MCOperand AMDGPUDisassembler::decodeOperand_VSrcV216(unsigned Val) const {
424   return decodeSrcOp(OPWV216, Val);
425 }
426 
427 MCOperand AMDGPUDisassembler::decodeOperand_VGPR_32(unsigned Val) const {
428   // Some instructions have operand restrictions beyond what the encoding
429   // allows. Some ordinarily VSrc_32 operands are VGPR_32, so clear the extra
430   // high bit.
431   Val &= 255;
432 
433   return createRegOperand(AMDGPU::VGPR_32RegClassID, Val);
434 }
435 
436 MCOperand AMDGPUDisassembler::decodeOperand_VReg_64(unsigned Val) const {
437   return createRegOperand(AMDGPU::VReg_64RegClassID, Val);
438 }
439 
440 MCOperand AMDGPUDisassembler::decodeOperand_VReg_96(unsigned Val) const {
441   return createRegOperand(AMDGPU::VReg_96RegClassID, Val);
442 }
443 
444 MCOperand AMDGPUDisassembler::decodeOperand_VReg_128(unsigned Val) const {
445   return createRegOperand(AMDGPU::VReg_128RegClassID, Val);
446 }
447 
448 MCOperand AMDGPUDisassembler::decodeOperand_SReg_32(unsigned Val) const {
449   // table-gen generated disassembler doesn't care about operand types
450   // leaving only registry class so SSrc_32 operand turns into SReg_32
451   // and therefore we accept immediates and literals here as well
452   return decodeSrcOp(OPW32, Val);
453 }
454 
455 MCOperand AMDGPUDisassembler::decodeOperand_SReg_32_XM0_XEXEC(
456   unsigned Val) const {
457   // SReg_32_XM0 is SReg_32 without M0 or EXEC_LO/EXEC_HI
458   return decodeOperand_SReg_32(Val);
459 }
460 
461 MCOperand AMDGPUDisassembler::decodeOperand_SReg_32_XEXEC_HI(
462   unsigned Val) const {
463   // SReg_32_XM0 is SReg_32 without EXEC_HI
464   return decodeOperand_SReg_32(Val);
465 }
466 
467 MCOperand AMDGPUDisassembler::decodeOperand_SReg_64(unsigned Val) const {
468   return decodeSrcOp(OPW64, Val);
469 }
470 
471 MCOperand AMDGPUDisassembler::decodeOperand_SReg_64_XEXEC(unsigned Val) const {
472   return decodeSrcOp(OPW64, Val);
473 }
474 
475 MCOperand AMDGPUDisassembler::decodeOperand_SReg_128(unsigned Val) const {
476   return decodeSrcOp(OPW128, Val);
477 }
478 
479 MCOperand AMDGPUDisassembler::decodeOperand_SReg_256(unsigned Val) const {
480   return decodeDstOp(OPW256, Val);
481 }
482 
483 MCOperand AMDGPUDisassembler::decodeOperand_SReg_512(unsigned Val) const {
484   return decodeDstOp(OPW512, Val);
485 }
486 
487 MCOperand AMDGPUDisassembler::decodeLiteralConstant() const {
488   // For now all literal constants are supposed to be unsigned integer
489   // ToDo: deal with signed/unsigned 64-bit integer constants
490   // ToDo: deal with float/double constants
491   if (!HasLiteral) {
492     if (Bytes.size() < 4) {
493       return errOperand(0, "cannot read literal, inst bytes left " +
494                         Twine(Bytes.size()));
495     }
496     HasLiteral = true;
497     Literal = eatBytes<uint32_t>(Bytes);
498   }
499   return MCOperand::createImm(Literal);
500 }
501 
502 MCOperand AMDGPUDisassembler::decodeIntImmed(unsigned Imm) {
503   using namespace AMDGPU::EncValues;
504 
505   assert(Imm >= INLINE_INTEGER_C_MIN && Imm <= INLINE_INTEGER_C_MAX);
506   return MCOperand::createImm((Imm <= INLINE_INTEGER_C_POSITIVE_MAX) ?
507     (static_cast<int64_t>(Imm) - INLINE_INTEGER_C_MIN) :
508     (INLINE_INTEGER_C_POSITIVE_MAX - static_cast<int64_t>(Imm)));
509       // Cast prevents negative overflow.
510 }
511 
512 static int64_t getInlineImmVal32(unsigned Imm) {
513   switch (Imm) {
514   case 240:
515     return FloatToBits(0.5f);
516   case 241:
517     return FloatToBits(-0.5f);
518   case 242:
519     return FloatToBits(1.0f);
520   case 243:
521     return FloatToBits(-1.0f);
522   case 244:
523     return FloatToBits(2.0f);
524   case 245:
525     return FloatToBits(-2.0f);
526   case 246:
527     return FloatToBits(4.0f);
528   case 247:
529     return FloatToBits(-4.0f);
530   case 248: // 1 / (2 * PI)
531     return 0x3e22f983;
532   default:
533     llvm_unreachable("invalid fp inline imm");
534   }
535 }
536 
537 static int64_t getInlineImmVal64(unsigned Imm) {
538   switch (Imm) {
539   case 240:
540     return DoubleToBits(0.5);
541   case 241:
542     return DoubleToBits(-0.5);
543   case 242:
544     return DoubleToBits(1.0);
545   case 243:
546     return DoubleToBits(-1.0);
547   case 244:
548     return DoubleToBits(2.0);
549   case 245:
550     return DoubleToBits(-2.0);
551   case 246:
552     return DoubleToBits(4.0);
553   case 247:
554     return DoubleToBits(-4.0);
555   case 248: // 1 / (2 * PI)
556     return 0x3fc45f306dc9c882;
557   default:
558     llvm_unreachable("invalid fp inline imm");
559   }
560 }
561 
562 static int64_t getInlineImmVal16(unsigned Imm) {
563   switch (Imm) {
564   case 240:
565     return 0x3800;
566   case 241:
567     return 0xB800;
568   case 242:
569     return 0x3C00;
570   case 243:
571     return 0xBC00;
572   case 244:
573     return 0x4000;
574   case 245:
575     return 0xC000;
576   case 246:
577     return 0x4400;
578   case 247:
579     return 0xC400;
580   case 248: // 1 / (2 * PI)
581     return 0x3118;
582   default:
583     llvm_unreachable("invalid fp inline imm");
584   }
585 }
586 
587 MCOperand AMDGPUDisassembler::decodeFPImmed(OpWidthTy Width, unsigned Imm) {
588   assert(Imm >= AMDGPU::EncValues::INLINE_FLOATING_C_MIN
589       && Imm <= AMDGPU::EncValues::INLINE_FLOATING_C_MAX);
590 
591   // ToDo: case 248: 1/(2*PI) - is allowed only on VI
592   switch (Width) {
593   case OPW32:
594     return MCOperand::createImm(getInlineImmVal32(Imm));
595   case OPW64:
596     return MCOperand::createImm(getInlineImmVal64(Imm));
597   case OPW16:
598   case OPWV216:
599     return MCOperand::createImm(getInlineImmVal16(Imm));
600   default:
601     llvm_unreachable("implement me");
602   }
603 }
604 
605 unsigned AMDGPUDisassembler::getVgprClassId(const OpWidthTy Width) const {
606   using namespace AMDGPU;
607 
608   assert(OPW_FIRST_ <= Width && Width < OPW_LAST_);
609   switch (Width) {
610   default: // fall
611   case OPW32:
612   case OPW16:
613   case OPWV216:
614     return VGPR_32RegClassID;
615   case OPW64: return VReg_64RegClassID;
616   case OPW128: return VReg_128RegClassID;
617   }
618 }
619 
620 unsigned AMDGPUDisassembler::getSgprClassId(const OpWidthTy Width) const {
621   using namespace AMDGPU;
622 
623   assert(OPW_FIRST_ <= Width && Width < OPW_LAST_);
624   switch (Width) {
625   default: // fall
626   case OPW32:
627   case OPW16:
628   case OPWV216:
629     return SGPR_32RegClassID;
630   case OPW64: return SGPR_64RegClassID;
631   case OPW128: return SGPR_128RegClassID;
632   case OPW256: return SGPR_256RegClassID;
633   case OPW512: return SGPR_512RegClassID;
634   }
635 }
636 
637 unsigned AMDGPUDisassembler::getTtmpClassId(const OpWidthTy Width) const {
638   using namespace AMDGPU;
639 
640   assert(OPW_FIRST_ <= Width && Width < OPW_LAST_);
641   switch (Width) {
642   default: // fall
643   case OPW32:
644   case OPW16:
645   case OPWV216:
646     return TTMP_32RegClassID;
647   case OPW64: return TTMP_64RegClassID;
648   case OPW128: return TTMP_128RegClassID;
649   case OPW256: return TTMP_256RegClassID;
650   case OPW512: return TTMP_512RegClassID;
651   }
652 }
653 
654 int AMDGPUDisassembler::getTTmpIdx(unsigned Val) const {
655   using namespace AMDGPU::EncValues;
656 
657   unsigned TTmpMin = isGFX9() ? TTMP_GFX9_MIN : TTMP_VI_MIN;
658   unsigned TTmpMax = isGFX9() ? TTMP_GFX9_MAX : TTMP_VI_MAX;
659 
660   return (TTmpMin <= Val && Val <= TTmpMax)? Val - TTmpMin : -1;
661 }
662 
663 MCOperand AMDGPUDisassembler::decodeSrcOp(const OpWidthTy Width, unsigned Val) const {
664   using namespace AMDGPU::EncValues;
665 
666   assert(Val < 512); // enum9
667 
668   if (VGPR_MIN <= Val && Val <= VGPR_MAX) {
669     return createRegOperand(getVgprClassId(Width), Val - VGPR_MIN);
670   }
671   if (Val <= SGPR_MAX) {
672     assert(SGPR_MIN == 0); // "SGPR_MIN <= Val" is always true and causes compilation warning.
673     return createSRegOperand(getSgprClassId(Width), Val - SGPR_MIN);
674   }
675 
676   int TTmpIdx = getTTmpIdx(Val);
677   if (TTmpIdx >= 0) {
678     return createSRegOperand(getTtmpClassId(Width), TTmpIdx);
679   }
680 
681   if (INLINE_INTEGER_C_MIN <= Val && Val <= INLINE_INTEGER_C_MAX)
682     return decodeIntImmed(Val);
683 
684   if (INLINE_FLOATING_C_MIN <= Val && Val <= INLINE_FLOATING_C_MAX)
685     return decodeFPImmed(Width, Val);
686 
687   if (Val == LITERAL_CONST)
688     return decodeLiteralConstant();
689 
690   switch (Width) {
691   case OPW32:
692   case OPW16:
693   case OPWV216:
694     return decodeSpecialReg32(Val);
695   case OPW64:
696     return decodeSpecialReg64(Val);
697   default:
698     llvm_unreachable("unexpected immediate type");
699   }
700 }
701 
702 MCOperand AMDGPUDisassembler::decodeDstOp(const OpWidthTy Width, unsigned Val) const {
703   using namespace AMDGPU::EncValues;
704 
705   assert(Val < 128);
706   assert(Width == OPW256 || Width == OPW512);
707 
708   if (Val <= SGPR_MAX) {
709     assert(SGPR_MIN == 0); // "SGPR_MIN <= Val" is always true and causes compilation warning.
710     return createSRegOperand(getSgprClassId(Width), Val - SGPR_MIN);
711   }
712 
713   int TTmpIdx = getTTmpIdx(Val);
714   if (TTmpIdx >= 0) {
715     return createSRegOperand(getTtmpClassId(Width), TTmpIdx);
716   }
717 
718   llvm_unreachable("unknown dst register");
719 }
720 
721 MCOperand AMDGPUDisassembler::decodeSpecialReg32(unsigned Val) const {
722   using namespace AMDGPU;
723 
724   switch (Val) {
725   case 102: return createRegOperand(FLAT_SCR_LO);
726   case 103: return createRegOperand(FLAT_SCR_HI);
727   case 104: return createRegOperand(XNACK_MASK_LO);
728   case 105: return createRegOperand(XNACK_MASK_HI);
729   case 106: return createRegOperand(VCC_LO);
730   case 107: return createRegOperand(VCC_HI);
731   case 108: assert(!isGFX9()); return createRegOperand(TBA_LO);
732   case 109: assert(!isGFX9()); return createRegOperand(TBA_HI);
733   case 110: assert(!isGFX9()); return createRegOperand(TMA_LO);
734   case 111: assert(!isGFX9()); return createRegOperand(TMA_HI);
735   case 124: return createRegOperand(M0);
736   case 126: return createRegOperand(EXEC_LO);
737   case 127: return createRegOperand(EXEC_HI);
738   case 235: return createRegOperand(SRC_SHARED_BASE);
739   case 236: return createRegOperand(SRC_SHARED_LIMIT);
740   case 237: return createRegOperand(SRC_PRIVATE_BASE);
741   case 238: return createRegOperand(SRC_PRIVATE_LIMIT);
742     // TODO: SRC_POPS_EXITING_WAVE_ID
743     // ToDo: no support for vccz register
744   case 251: break;
745     // ToDo: no support for execz register
746   case 252: break;
747   case 253: return createRegOperand(SCC);
748   default: break;
749   }
750   return errOperand(Val, "unknown operand encoding " + Twine(Val));
751 }
752 
753 MCOperand AMDGPUDisassembler::decodeSpecialReg64(unsigned Val) const {
754   using namespace AMDGPU;
755 
756   switch (Val) {
757   case 102: return createRegOperand(FLAT_SCR);
758   case 104: return createRegOperand(XNACK_MASK);
759   case 106: return createRegOperand(VCC);
760   case 108: assert(!isGFX9()); return createRegOperand(TBA);
761   case 110: assert(!isGFX9()); return createRegOperand(TMA);
762   case 126: return createRegOperand(EXEC);
763   default: break;
764   }
765   return errOperand(Val, "unknown operand encoding " + Twine(Val));
766 }
767 
768 MCOperand AMDGPUDisassembler::decodeSDWASrc(const OpWidthTy Width,
769                                             const unsigned Val) const {
770   using namespace AMDGPU::SDWA;
771   using namespace AMDGPU::EncValues;
772 
773   if (STI.getFeatureBits()[AMDGPU::FeatureGFX9]) {
774     // XXX: static_cast<int> is needed to avoid stupid warning:
775     // compare with unsigned is always true
776     if (SDWA9EncValues::SRC_VGPR_MIN <= static_cast<int>(Val) &&
777         Val <= SDWA9EncValues::SRC_VGPR_MAX) {
778       return createRegOperand(getVgprClassId(Width),
779                               Val - SDWA9EncValues::SRC_VGPR_MIN);
780     }
781     if (SDWA9EncValues::SRC_SGPR_MIN <= Val &&
782         Val <= SDWA9EncValues::SRC_SGPR_MAX) {
783       return createSRegOperand(getSgprClassId(Width),
784                                Val - SDWA9EncValues::SRC_SGPR_MIN);
785     }
786     if (SDWA9EncValues::SRC_TTMP_MIN <= Val &&
787         Val <= SDWA9EncValues::SRC_TTMP_MAX) {
788       return createSRegOperand(getTtmpClassId(Width),
789                                Val - SDWA9EncValues::SRC_TTMP_MIN);
790     }
791 
792     const unsigned SVal = Val - SDWA9EncValues::SRC_SGPR_MIN;
793 
794     if (INLINE_INTEGER_C_MIN <= SVal && SVal <= INLINE_INTEGER_C_MAX)
795       return decodeIntImmed(SVal);
796 
797     if (INLINE_FLOATING_C_MIN <= SVal && SVal <= INLINE_FLOATING_C_MAX)
798       return decodeFPImmed(Width, SVal);
799 
800     return decodeSpecialReg32(SVal);
801   } else if (STI.getFeatureBits()[AMDGPU::FeatureVolcanicIslands]) {
802     return createRegOperand(getVgprClassId(Width), Val);
803   }
804   llvm_unreachable("unsupported target");
805 }
806 
807 MCOperand AMDGPUDisassembler::decodeSDWASrc16(unsigned Val) const {
808   return decodeSDWASrc(OPW16, Val);
809 }
810 
811 MCOperand AMDGPUDisassembler::decodeSDWASrc32(unsigned Val) const {
812   return decodeSDWASrc(OPW32, Val);
813 }
814 
815 MCOperand AMDGPUDisassembler::decodeSDWAVopcDst(unsigned Val) const {
816   using namespace AMDGPU::SDWA;
817 
818   assert(STI.getFeatureBits()[AMDGPU::FeatureGFX9] &&
819          "SDWAVopcDst should be present only on GFX9");
820   if (Val & SDWA9EncValues::VOPC_DST_VCC_MASK) {
821     Val &= SDWA9EncValues::VOPC_DST_SGPR_MASK;
822 
823     int TTmpIdx = getTTmpIdx(Val);
824     if (TTmpIdx >= 0) {
825       return createSRegOperand(getTtmpClassId(OPW64), TTmpIdx);
826     } else if (Val > AMDGPU::EncValues::SGPR_MAX) {
827       return decodeSpecialReg64(Val);
828     } else {
829       return createSRegOperand(getSgprClassId(OPW64), Val);
830     }
831   } else {
832     return createRegOperand(AMDGPU::VCC);
833   }
834 }
835 
836 bool AMDGPUDisassembler::isVI() const {
837   return STI.getFeatureBits()[AMDGPU::FeatureVolcanicIslands];
838 }
839 
840 bool AMDGPUDisassembler::isGFX9() const {
841   return STI.getFeatureBits()[AMDGPU::FeatureGFX9];
842 }
843 
844 //===----------------------------------------------------------------------===//
845 // AMDGPUSymbolizer
846 //===----------------------------------------------------------------------===//
847 
848 // Try to find symbol name for specified label
849 bool AMDGPUSymbolizer::tryAddingSymbolicOperand(MCInst &Inst,
850                                 raw_ostream &/*cStream*/, int64_t Value,
851                                 uint64_t /*Address*/, bool IsBranch,
852                                 uint64_t /*Offset*/, uint64_t /*InstSize*/) {
853   using SymbolInfoTy = std::tuple<uint64_t, StringRef, uint8_t>;
854   using SectionSymbolsTy = std::vector<SymbolInfoTy>;
855 
856   if (!IsBranch) {
857     return false;
858   }
859 
860   auto *Symbols = static_cast<SectionSymbolsTy *>(DisInfo);
861   auto Result = std::find_if(Symbols->begin(), Symbols->end(),
862                              [Value](const SymbolInfoTy& Val) {
863                                 return std::get<0>(Val) == static_cast<uint64_t>(Value)
864                                     && std::get<2>(Val) == ELF::STT_NOTYPE;
865                              });
866   if (Result != Symbols->end()) {
867     auto *Sym = Ctx.getOrCreateSymbol(std::get<1>(*Result));
868     const auto *Add = MCSymbolRefExpr::create(Sym, Ctx);
869     Inst.addOperand(MCOperand::createExpr(Add));
870     return true;
871   }
872   return false;
873 }
874 
875 void AMDGPUSymbolizer::tryAddingPcLoadReferenceComment(raw_ostream &cStream,
876                                                        int64_t Value,
877                                                        uint64_t Address) {
878   llvm_unreachable("unimplemented");
879 }
880 
881 //===----------------------------------------------------------------------===//
882 // Initialization
883 //===----------------------------------------------------------------------===//
884 
885 static MCSymbolizer *createAMDGPUSymbolizer(const Triple &/*TT*/,
886                               LLVMOpInfoCallback /*GetOpInfo*/,
887                               LLVMSymbolLookupCallback /*SymbolLookUp*/,
888                               void *DisInfo,
889                               MCContext *Ctx,
890                               std::unique_ptr<MCRelocationInfo> &&RelInfo) {
891   return new AMDGPUSymbolizer(*Ctx, std::move(RelInfo), DisInfo);
892 }
893 
894 static MCDisassembler *createAMDGPUDisassembler(const Target &T,
895                                                 const MCSubtargetInfo &STI,
896                                                 MCContext &Ctx) {
897   return new AMDGPUDisassembler(STI, Ctx, T.createMCInstrInfo());
898 }
899 
900 extern "C" void LLVMInitializeAMDGPUDisassembler() {
901   TargetRegistry::RegisterMCDisassembler(getTheGCNTarget(),
902                                          createAMDGPUDisassembler);
903   TargetRegistry::RegisterMCSymbolizer(getTheGCNTarget(),
904                                        createAMDGPUSymbolizer);
905 }
906