1 //===- Disassembler.cpp - Disassembler for hex strings --------------------===// 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 // This class implements the disassembler of strings of bytes written in 11 // hexadecimal, from standard input or from a file. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "Disassembler.h" 16 #include "../../lib/MC/MCDisassembler/EDDisassembler.h" 17 #include "../../lib/MC/MCDisassembler/EDInst.h" 18 #include "../../lib/MC/MCDisassembler/EDOperand.h" 19 #include "../../lib/MC/MCDisassembler/EDToken.h" 20 #include "llvm/MC/MCDisassembler.h" 21 #include "llvm/MC/MCInst.h" 22 #include "llvm/MC/MCStreamer.h" 23 #include "llvm/MC/MCSubtargetInfo.h" 24 #include "llvm/ADT/OwningPtr.h" 25 #include "llvm/ADT/Triple.h" 26 #include "llvm/Support/MemoryBuffer.h" 27 #include "llvm/Support/MemoryObject.h" 28 #include "llvm/Support/SourceMgr.h" 29 #include "llvm/Support/TargetRegistry.h" 30 #include "llvm/Support/raw_ostream.h" 31 32 using namespace llvm; 33 34 typedef std::vector<std::pair<unsigned char, const char*> > ByteArrayTy; 35 36 namespace { 37 class VectorMemoryObject : public MemoryObject { 38 private: 39 const ByteArrayTy &Bytes; 40 public: 41 VectorMemoryObject(const ByteArrayTy &bytes) : Bytes(bytes) {} 42 43 uint64_t getBase() const { return 0; } 44 uint64_t getExtent() const { return Bytes.size(); } 45 46 int readByte(uint64_t Addr, uint8_t *Byte) const { 47 if (Addr >= getExtent()) 48 return -1; 49 *Byte = Bytes[Addr].first; 50 return 0; 51 } 52 }; 53 } 54 55 static bool PrintInsts(const MCDisassembler &DisAsm, 56 const ByteArrayTy &Bytes, 57 SourceMgr &SM, raw_ostream &Out, 58 MCStreamer &Streamer) { 59 // Wrap the vector in a MemoryObject. 60 VectorMemoryObject memoryObject(Bytes); 61 62 // Disassemble it to strings. 63 uint64_t Size; 64 uint64_t Index; 65 66 for (Index = 0; Index < Bytes.size(); Index += Size) { 67 MCInst Inst; 68 69 MCDisassembler::DecodeStatus S; 70 S = DisAsm.getInstruction(Inst, Size, memoryObject, Index, 71 /*REMOVE*/ nulls(), nulls()); 72 switch (S) { 73 case MCDisassembler::Fail: 74 SM.PrintMessage(SMLoc::getFromPointer(Bytes[Index].second), 75 SourceMgr::DK_Warning, 76 "invalid instruction encoding"); 77 if (Size == 0) 78 Size = 1; // skip illegible bytes 79 break; 80 81 case MCDisassembler::SoftFail: 82 SM.PrintMessage(SMLoc::getFromPointer(Bytes[Index].second), 83 SourceMgr::DK_Warning, 84 "potentially undefined instruction encoding"); 85 // Fall through 86 87 case MCDisassembler::Success: 88 Streamer.EmitInstruction(Inst); 89 break; 90 } 91 } 92 93 return false; 94 } 95 96 static bool ByteArrayFromString(ByteArrayTy &ByteArray, 97 StringRef &Str, 98 SourceMgr &SM) { 99 while (!Str.empty()) { 100 // Strip horizontal whitespace. 101 if (size_t Pos = Str.find_first_not_of(" \t\r")) { 102 Str = Str.substr(Pos); 103 continue; 104 } 105 106 // If this is the end of a line or start of a comment, remove the rest of 107 // the line. 108 if (Str[0] == '\n' || Str[0] == '#') { 109 // Strip to the end of line if we already processed any bytes on this 110 // line. This strips the comment and/or the \n. 111 if (Str[0] == '\n') { 112 Str = Str.substr(1); 113 } else { 114 Str = Str.substr(Str.find_first_of('\n')); 115 if (!Str.empty()) 116 Str = Str.substr(1); 117 } 118 continue; 119 } 120 121 // Get the current token. 122 size_t Next = Str.find_first_of(" \t\n\r#"); 123 StringRef Value = Str.substr(0, Next); 124 125 // Convert to a byte and add to the byte vector. 126 unsigned ByteVal; 127 if (Value.getAsInteger(0, ByteVal) || ByteVal > 255) { 128 // If we have an error, print it and skip to the end of line. 129 SM.PrintMessage(SMLoc::getFromPointer(Value.data()), SourceMgr::DK_Error, 130 "invalid input token"); 131 Str = Str.substr(Str.find('\n')); 132 ByteArray.clear(); 133 continue; 134 } 135 136 ByteArray.push_back(std::make_pair((unsigned char)ByteVal, Value.data())); 137 Str = Str.substr(Next); 138 } 139 140 return false; 141 } 142 143 int Disassembler::disassemble(const Target &T, 144 const std::string &Triple, 145 MCSubtargetInfo &STI, 146 MCStreamer &Streamer, 147 MemoryBuffer &Buffer, 148 SourceMgr &SM, 149 raw_ostream &Out) { 150 OwningPtr<const MCDisassembler> DisAsm(T.createMCDisassembler(STI)); 151 if (!DisAsm) { 152 errs() << "error: no disassembler for target " << Triple << "\n"; 153 return -1; 154 } 155 156 // Set up initial section manually here 157 Streamer.InitSections(); 158 159 bool ErrorOccurred = false; 160 161 // Convert the input to a vector for disassembly. 162 ByteArrayTy ByteArray; 163 StringRef Str = Buffer.getBuffer(); 164 165 ErrorOccurred |= ByteArrayFromString(ByteArray, Str, SM); 166 167 if (!ByteArray.empty()) 168 ErrorOccurred |= PrintInsts(*DisAsm, ByteArray, SM, Out, Streamer); 169 170 return ErrorOccurred; 171 } 172 173 static int byteArrayReader(uint8_t *B, uint64_t A, void *Arg) { 174 ByteArrayTy &ByteArray = *((ByteArrayTy*)Arg); 175 176 if (A >= ByteArray.size()) 177 return -1; 178 179 *B = ByteArray[A].first; 180 181 return 0; 182 } 183 184 static int verboseEvaluator(uint64_t *V, unsigned R, void *Arg) { 185 EDDisassembler &disassembler = *(EDDisassembler *)((void **)Arg)[0]; 186 raw_ostream &Out = *(raw_ostream *)((void **)Arg)[1]; 187 188 if (const char *regName = disassembler.nameWithRegisterID(R)) 189 Out << "[" << regName << "/" << R << "]"; 190 191 if (disassembler.registerIsStackPointer(R)) 192 Out << "(sp)"; 193 if (disassembler.registerIsProgramCounter(R)) 194 Out << "(pc)"; 195 196 *V = 0; 197 return 0; 198 } 199 200 int Disassembler::disassembleEnhanced(const std::string &TS, 201 MemoryBuffer &Buffer, 202 SourceMgr &SM, 203 raw_ostream &Out) { 204 ByteArrayTy ByteArray; 205 StringRef Str = Buffer.getBuffer(); 206 207 if (ByteArrayFromString(ByteArray, Str, SM)) { 208 return -1; 209 } 210 211 Triple T(TS); 212 EDDisassembler::AssemblySyntax AS; 213 214 switch (T.getArch()) { 215 default: 216 errs() << "error: no default assembly syntax for " << TS.c_str() << "\n"; 217 return -1; 218 case Triple::arm: 219 case Triple::thumb: 220 AS = EDDisassembler::kEDAssemblySyntaxARMUAL; 221 break; 222 case Triple::x86: 223 case Triple::x86_64: 224 AS = EDDisassembler::kEDAssemblySyntaxX86ATT; 225 break; 226 } 227 228 OwningPtr<EDDisassembler> 229 disassembler(EDDisassembler::getDisassembler(TS.c_str(), AS)); 230 231 if (disassembler == 0) { 232 errs() << "error: couldn't get disassembler for " << TS << '\n'; 233 return -1; 234 } 235 236 while (ByteArray.size()) { 237 OwningPtr<EDInst> 238 inst(disassembler->createInst(byteArrayReader, 0, &ByteArray)); 239 240 if (inst == 0) { 241 errs() << "error: Didn't get an instruction\n"; 242 return -1; 243 } 244 245 ByteArray.erase (ByteArray.begin(), ByteArray.begin() + inst->byteSize()); 246 247 unsigned numTokens = inst->numTokens(); 248 if ((int)numTokens < 0) { 249 errs() << "error: couldn't count the instruction's tokens\n"; 250 return -1; 251 } 252 253 for (unsigned tokenIndex = 0; tokenIndex != numTokens; ++tokenIndex) { 254 EDToken *token; 255 256 if (inst->getToken(token, tokenIndex)) { 257 errs() << "error: Couldn't get token\n"; 258 return -1; 259 } 260 261 const char *buf; 262 if (token->getString(buf)) { 263 errs() << "error: Couldn't get string for token\n"; 264 return -1; 265 } 266 267 Out << '['; 268 int operandIndex = token->operandID(); 269 270 if (operandIndex >= 0) 271 Out << operandIndex << "-"; 272 273 switch (token->type()) { 274 case EDToken::kTokenWhitespace: Out << "w"; break; 275 case EDToken::kTokenPunctuation: Out << "p"; break; 276 case EDToken::kTokenOpcode: Out << "o"; break; 277 case EDToken::kTokenLiteral: Out << "l"; break; 278 case EDToken::kTokenRegister: Out << "r"; break; 279 } 280 281 Out << ":" << buf; 282 283 if (token->type() == EDToken::kTokenLiteral) { 284 Out << "="; 285 if (token->literalSign()) 286 Out << "-"; 287 uint64_t absoluteValue; 288 if (token->literalAbsoluteValue(absoluteValue)) { 289 errs() << "error: Couldn't get the value of a literal token\n"; 290 return -1; 291 } 292 Out << absoluteValue; 293 } else if (token->type() == EDToken::kTokenRegister) { 294 Out << "="; 295 unsigned regID; 296 if (token->registerID(regID)) { 297 errs() << "error: Couldn't get the ID of a register token\n"; 298 return -1; 299 } 300 Out << "r" << regID; 301 } 302 303 Out << "]"; 304 } 305 306 Out << " "; 307 308 if (inst->isBranch()) 309 Out << "<br> "; 310 if (inst->isMove()) 311 Out << "<mov> "; 312 313 unsigned numOperands = inst->numOperands(); 314 315 if ((int)numOperands < 0) { 316 errs() << "error: Couldn't count operands\n"; 317 return -1; 318 } 319 320 for (unsigned operandIndex = 0; operandIndex != numOperands; 321 ++operandIndex) { 322 Out << operandIndex << ":"; 323 324 EDOperand *operand; 325 if (inst->getOperand(operand, operandIndex)) { 326 errs() << "error: couldn't get operand\n"; 327 return -1; 328 } 329 330 uint64_t evaluatedResult; 331 void *Arg[] = { disassembler.get(), &Out }; 332 if (operand->evaluate(evaluatedResult, verboseEvaluator, Arg)) { 333 errs() << "error: Couldn't evaluate an operand\n"; 334 return -1; 335 } 336 Out << "=" << evaluatedResult << " "; 337 } 338 339 Out << '\n'; 340 } 341 342 return 0; 343 } 344
