1 //===-- AMDGPUDisassembler.cpp - Disassembler for AMDGPU ISA --------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 //===----------------------------------------------------------------------===//
14 /// This file contains definition for AMDGPU ISA disassembler
16 //===----------------------------------------------------------------------===//
18 // ToDo: What to do with instruction suffixes (v_mov_b32 vs v_mov_b32_e32)?
20 #include "AMDGPUDisassembler.h"
22 #include "AMDGPURegisterInfo.h"
23 #include "Utils/AMDGPUBaseInfo.h"
25 #include "llvm/MC/MCContext.h"
26 #include "llvm/MC/MCFixedLenDisassembler.h"
27 #include "llvm/MC/MCInst.h"
28 #include "llvm/MC/MCInstrDesc.h"
29 #include "llvm/MC/MCSubtargetInfo.h"
30 #include "llvm/Support/Endian.h"
31 #include "llvm/Support/Debug.h"
32 #include "llvm/Support/TargetRegistry.h"
37 #define DEBUG_TYPE "amdgpu-disassembler"
39 typedef llvm::MCDisassembler::DecodeStatus DecodeStatus;
42 inline static MCDisassembler::DecodeStatus
43 addOperand(MCInst &Inst, const MCOperand& Opnd) {
44 Inst.addOperand(Opnd);
45 return Opnd.isValid() ?
46 MCDisassembler::Success :
47 MCDisassembler::SoftFail;
50 #define DECODE_OPERAND2(RegClass, DecName) \
51 static DecodeStatus Decode##RegClass##RegisterClass(MCInst &Inst, \
54 const void *Decoder) { \
55 auto DAsm = static_cast<const AMDGPUDisassembler*>(Decoder); \
56 return addOperand(Inst, DAsm->decodeOperand_##DecName(Imm)); \
59 #define DECODE_OPERAND(RegClass) DECODE_OPERAND2(RegClass, RegClass)
61 DECODE_OPERAND(VGPR_32)
65 DECODE_OPERAND(VReg_64)
66 DECODE_OPERAND(VReg_96)
67 DECODE_OPERAND(VReg_128)
69 DECODE_OPERAND(SReg_32)
70 DECODE_OPERAND(SReg_64)
71 DECODE_OPERAND(SReg_128)
72 DECODE_OPERAND(SReg_256)
74 #define GET_SUBTARGETINFO_ENUM
75 #include "AMDGPUGenSubtargetInfo.inc"
76 #undef GET_SUBTARGETINFO_ENUM
78 #include "AMDGPUGenDisassemblerTables.inc"
80 //===----------------------------------------------------------------------===//
82 //===----------------------------------------------------------------------===//
84 static inline uint32_t eatB32(ArrayRef<uint8_t>& Bytes) {
85 assert(Bytes.size() >= sizeof eatB32(Bytes));
86 const auto Res = support::endian::read32le(Bytes.data());
87 Bytes = Bytes.slice(sizeof Res);
91 DecodeStatus AMDGPUDisassembler::tryDecodeInst(const uint8_t* Table,
94 uint64_t Address) const {
95 assert(MI.getOpcode() == 0);
96 assert(MI.getNumOperands() == 0);
98 const auto SavedBytes = Bytes;
99 if (decodeInstruction(Table, TmpInst, Inst, Address, this, STI)) {
101 return MCDisassembler::Success;
104 return MCDisassembler::Fail;
107 DecodeStatus AMDGPUDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
108 ArrayRef<uint8_t> Bytes_,
111 raw_ostream &CS) const {
114 // ToDo: AMDGPUDisassembler supports only VI ISA.
115 assert(AMDGPU::isVI(STI) && "Can disassemble only VI ISA.");
117 const unsigned MaxInstBytesNum = (std::min)((size_t)8, Bytes_.size());
118 Bytes = Bytes_.slice(0, MaxInstBytesNum);
120 DecodeStatus Res = MCDisassembler::Fail;
122 // ToDo: better to switch enc len using some bit predicate
123 // but it is unknown yet, so try all we can
124 if (Bytes.size() < 4) break;
125 const uint32_t DW = eatB32(Bytes);
126 Res = tryDecodeInst(DecoderTableVI32, MI, DW, Address);
129 Res = tryDecodeInst(DecoderTableAMDGPU32, MI, DW, Address);
132 if (Bytes.size() < 4) break;
133 const uint64_t QW = ((uint64_t)eatB32(Bytes) << 32) | DW;
134 Res = tryDecodeInst(DecoderTableVI64, MI, QW, Address);
137 Res = tryDecodeInst(DecoderTableAMDGPU64, MI, QW, Address);
140 Size = Res ? (MaxInstBytesNum - Bytes.size()) : 0;
144 const char* AMDGPUDisassembler::getRegClassName(unsigned RegClassID) const {
145 return getContext().getRegisterInfo()->
146 getRegClassName(&AMDGPUMCRegisterClasses[RegClassID]);
150 MCOperand AMDGPUDisassembler::errOperand(unsigned V,
151 const Twine& ErrMsg) const {
152 *CommentStream << "Error: " + ErrMsg;
154 // ToDo: add support for error operands to MCInst.h
155 // return MCOperand::createError(V);
160 MCOperand AMDGPUDisassembler::createRegOperand(unsigned int RegId) const {
161 return MCOperand::createReg(RegId);
165 MCOperand AMDGPUDisassembler::createRegOperand(unsigned RegClassID,
166 unsigned Val) const {
167 const auto& RegCl = AMDGPUMCRegisterClasses[RegClassID];
168 if (Val >= RegCl.getNumRegs())
169 return errOperand(Val, Twine(getRegClassName(RegClassID)) +
170 ": unknown register " + Twine(Val));
171 return createRegOperand(RegCl.getRegister(Val));
175 MCOperand AMDGPUDisassembler::createSRegOperand(unsigned SRegClassID,
176 unsigned Val) const {
177 // ToDo: SI/CI have 104 SGPRs, VI - 102
178 // Valery: here we accepting as much as we can, let assembler sort it out
180 switch (SRegClassID) {
181 case AMDGPU::SGPR_32RegClassID:
182 case AMDGPU::SReg_32RegClassID: break;
183 case AMDGPU::SGPR_64RegClassID:
184 case AMDGPU::SReg_64RegClassID: shift = 1; break;
185 case AMDGPU::SReg_128RegClassID:
186 // ToDo: unclear if s[100:104] is available on VI. Can we use VCC as SGPR in
188 case AMDGPU::SReg_256RegClassID:
189 // ToDo: unclear if s[96:104] is available on VI. Can we use VCC as SGPR in
191 case AMDGPU::SReg_512RegClassID: shift = 2; break;
192 // ToDo: unclear if s[88:104] is available on VI. Can we use VCC as SGPR in
194 default: assert(false); break;
196 if (Val % (1 << shift))
197 *CommentStream << "Warning: " << getRegClassName(SRegClassID)
198 << ": scalar reg isn't aligned " << Val;
199 return createRegOperand(SRegClassID, Val >> shift);
202 MCOperand AMDGPUDisassembler::decodeOperand_VS_32(unsigned Val) const {
203 return decodeSrcOp(OP32, Val);
206 MCOperand AMDGPUDisassembler::decodeOperand_VS_64(unsigned Val) const {
207 return decodeSrcOp(OP64, Val);
210 MCOperand AMDGPUDisassembler::decodeOperand_VGPR_32(unsigned Val) const {
211 return createRegOperand(AMDGPU::VGPR_32RegClassID, Val);
214 MCOperand AMDGPUDisassembler::decodeOperand_VReg_64(unsigned Val) const {
215 return createRegOperand(AMDGPU::VReg_64RegClassID, Val);
218 MCOperand AMDGPUDisassembler::decodeOperand_VReg_96(unsigned Val) const {
219 return createRegOperand(AMDGPU::VReg_96RegClassID, Val);
222 MCOperand AMDGPUDisassembler::decodeOperand_VReg_128(unsigned Val) const {
223 return createRegOperand(AMDGPU::VReg_128RegClassID, Val);
226 MCOperand AMDGPUDisassembler::decodeOperand_SGPR_32(unsigned Val) const {
227 return createSRegOperand(AMDGPU::SGPR_32RegClassID, Val);
230 MCOperand AMDGPUDisassembler::decodeOperand_SReg_32(unsigned Val) const {
231 // table-gen generated disassembler doesn't care about operand types
232 // leaving only registry class so SSrc_32 operand turns into SReg_32
233 // and therefore we accept immediates and literals here as well
234 return decodeSrcOp(OP32, Val);
237 MCOperand AMDGPUDisassembler::decodeOperand_SReg_64(unsigned Val) const {
238 // see decodeOperand_SReg_32 comment
239 return decodeSrcOp(OP64, Val);
242 MCOperand AMDGPUDisassembler::decodeOperand_SReg_128(unsigned Val) const {
243 return createSRegOperand(AMDGPU::SReg_128RegClassID, Val);
246 MCOperand AMDGPUDisassembler::decodeOperand_SReg_256(unsigned Val) const {
247 return createSRegOperand(AMDGPU::SReg_256RegClassID, Val);
250 MCOperand AMDGPUDisassembler::decodeOperand_SReg_512(unsigned Val) const {
251 return createSRegOperand(AMDGPU::SReg_512RegClassID, Val);
255 MCOperand AMDGPUDisassembler::decodeLiteralConstant() const {
256 // For now all literal constants are supposed to be unsigned integer
257 // ToDo: deal with signed/unsigned 64-bit integer constants
258 // ToDo: deal with float/double constants
259 if (Bytes.size() < 4)
260 return errOperand(0, "cannot read literal, inst bytes left " +
261 Twine(Bytes.size()));
262 return MCOperand::createImm(eatB32(Bytes));
265 MCOperand AMDGPUDisassembler::decodeIntImmed(unsigned Imm) {
266 assert(Imm >= 128 && Imm <= 208);
267 return MCOperand::createImm((Imm <= 192) ? (Imm - 128) : (192 - Imm));
270 MCOperand AMDGPUDisassembler::decodeFPImmed(bool Is32, unsigned Imm) {
271 assert(Imm >= 240 && Imm <= 248);
272 // ToDo: case 248: 1/(2*PI) - is allowed only on VI
273 // ToDo: AMDGPUInstPrinter does not support 1/(2*PI). It consider 1/(2*PI) as
277 case 240: V = 0.5f; break;
278 case 241: V = -0.5f; break;
279 case 242: V = 1.0f; break;
280 case 243: V = -1.0f; break;
281 case 244: V = 2.0f; break;
282 case 245: V = -2.0f; break;
283 case 246: V = 4.0f; break;
284 case 247: V = -4.0f; break;
285 case 248: return MCOperand::createImm(Is32 ? // 1/(2*PI)
290 return MCOperand::createImm(Is32? FloatToBits(V) : DoubleToBits(V));
293 MCOperand AMDGPUDisassembler::decodeSrcOp(bool Is32, unsigned Val) const {
294 using namespace AMDGPU;
295 assert(Val < 512); // enum9
298 return createRegOperand(Is32 ? VGPR_32RegClassID : VReg_64RegClassID,
301 return createSRegOperand(Is32 ? SGPR_32RegClassID : SGPR_64RegClassID,
304 if (Val >= 128 && Val <= 208)
305 return decodeIntImmed(Val);
307 if (Val >= 240 && Val <= 248)
308 return decodeFPImmed(Is32, Val);
311 return decodeLiteralConstant();
313 return Is32 ? decodeSpecialReg32(Val) : decodeSpecialReg64(Val);
316 MCOperand AMDGPUDisassembler::decodeSpecialReg32(unsigned Val) const {
317 using namespace AMDGPU;
319 case 102: return createRegOperand(getMCReg(FLAT_SCR_LO, STI));
320 case 103: return createRegOperand(getMCReg(FLAT_SCR_HI, STI));
321 // ToDo: no support for xnack_mask_lo/_hi register
324 case 106: return createRegOperand(VCC_LO);
325 case 107: return createRegOperand(VCC_HI);
326 // ToDo: no support for tba_lo/_hi register
329 // ToDo: no support for tma_lo/_hi register
332 // ToDo: no support for ttmp[0:11] register
345 case 124: return createRegOperand(M0);
346 case 126: return createRegOperand(EXEC_LO);
347 case 127: return createRegOperand(EXEC_HI);
348 // ToDo: no support for vccz register
350 // ToDo: no support for execz register
352 case 253: return createRegOperand(SCC);
355 return errOperand(Val, "unknown operand encoding " + Twine(Val));
358 MCOperand AMDGPUDisassembler::decodeSpecialReg64(unsigned Val) const {
359 using namespace AMDGPU;
361 case 102: return createRegOperand(getMCReg(FLAT_SCR, STI));
362 case 106: return createRegOperand(VCC);
363 case 126: return createRegOperand(EXEC);
366 return errOperand(Val, "unknown operand encoding " + Twine(Val));
369 static MCDisassembler *createAMDGPUDisassembler(const Target &T,
370 const MCSubtargetInfo &STI,
372 return new AMDGPUDisassembler(STI, Ctx);
375 extern "C" void LLVMInitializeAMDGPUDisassembler() {
376 TargetRegistry::RegisterMCDisassembler(TheGCNTarget, createAMDGPUDisassembler);