tools/llvm-mc/Disassembler.cpp

   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/MCAsmInfo.h"
  21 #include "llvm/MC/MCDisassembler.h"
  22 #include "llvm/MC/MCInst.h"
  23 #include "llvm/MC/MCInstPrinter.h"
  24 #include "llvm/Target/TargetRegistry.h"
  25 #include "llvm/ADT/OwningPtr.h"
  26 #include "llvm/ADT/Triple.h"
  27 #include "llvm/ADT/Twine.h"
  28 #include "llvm/Support/MemoryBuffer.h"
  29 #include "llvm/Support/MemoryObject.h"
  30 #include "llvm/Support/raw_ostream.h"
  31 #include "llvm/Support/SourceMgr.h"
  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                        MCInstPrinter &Printer, const ByteArrayTy &Bytes,
  57                        SourceMgr &SM, raw_ostream &Out) {
  58   // Wrap the vector in a MemoryObject.
  59   VectorMemoryObject memoryObject(Bytes);
  60
  61   // Disassemble it to strings.
  62   uint64_t Size;
  63   uint64_t Index;
  64
  65   for (Index = 0; Index < Bytes.size(); Index += Size) {
  66     MCInst Inst;
  67
  68     if (DisAsm.getInstruction(Inst, Size, memoryObject, Index,
  69                                /*REMOVE*/ nulls())) {
  70       Printer.printInst(&Inst, Out);
  71       Out << "\n";
  72     } else {
  73       SM.PrintMessage(SMLoc::getFromPointer(Bytes[Index].second),
  74                       "invalid instruction encoding", "warning");
  75       if (Size == 0)
  76         Size = 1; // skip illegible bytes
  77     }
  78   }
  79
  80   return false;
  81 }
  82
  83 static bool ByteArrayFromString(ByteArrayTy &ByteArray,
  84                                 StringRef &Str,
  85                                 SourceMgr &SM) {
  86   while (!Str.empty()) {
  87     // Strip horizontal whitespace.
  88     if (size_t Pos = Str.find_first_not_of(" \t\r")) {
  89       Str = Str.substr(Pos);
  90       continue;
  91     }
  92
  93     // If this is the end of a line or start of a comment, remove the rest of
  94     // the line.
  95     if (Str[0] == '\n' || Str[0] == '#') {
  96       // Strip to the end of line if we already processed any bytes on this
  97       // line.  This strips the comment and/or the \n.
  98       if (Str[0] == '\n') {
  99         Str = Str.substr(1);
 100       } else {
 101         Str = Str.substr(Str.find_first_of('\n'));
 102         if (!Str.empty())
 103           Str = Str.substr(1);
 104       }
 105       continue;
 106     }
 107
 108     // Get the current token.
 109     size_t Next = Str.find_first_of(" \t\n\r#");
 110     StringRef Value = Str.substr(0, Next);
 111
 112     // Convert to a byte and add to the byte vector.
 113     unsigned ByteVal;
 114     if (Value.getAsInteger(0, ByteVal) || ByteVal > 255) {
 115       // If we have an error, print it and skip to the end of line.
 116       SM.PrintMessage(SMLoc::getFromPointer(Value.data()),
 117                       "invalid input token", "error");
 118       Str = Str.substr(Str.find('\n'));
 119       ByteArray.clear();
 120       continue;
 121     }
 122
 123     ByteArray.push_back(std::make_pair((unsigned char)ByteVal, Value.data()));
 124     Str = Str.substr(Next);
 125   }
 126
 127   return false;
 128 }
 129
 130 int Disassembler::disassemble(const Target &T,
 131                               const std::string &Triple,
 132                               MemoryBuffer &Buffer,
 133                               raw_ostream &Out) {
 134   // Set up disassembler.
 135   OwningPtr<const MCAsmInfo> AsmInfo(T.createAsmInfo(Triple));
 136
 137   if (!AsmInfo) {
 138     errs() << "error: no assembly info for target " << Triple << "\n";
 139     return -1;
 140   }
 141
 142   OwningPtr<const MCDisassembler> DisAsm(T.createMCDisassembler());
 143   if (!DisAsm) {
 144     errs() << "error: no disassembler for target " << Triple << "\n";
 145     return -1;
 146   }
 147
 148   int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
 149   OwningPtr<MCInstPrinter> IP(T.createMCInstPrinter(AsmPrinterVariant,
 150                                                     *AsmInfo));
 151   if (!IP) {
 152     errs() << "error: no instruction printer for target " << Triple << '\n';
 153     return -1;
 154   }
 155
 156   bool ErrorOccurred = false;
 157
 158   SourceMgr SM;
 159   SM.AddNewSourceBuffer(&Buffer, SMLoc());
 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, *IP, ByteArray, SM, Out);
 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                                       raw_ostream &Out) {
 203   ByteArrayTy ByteArray;
 204   StringRef Str = Buffer.getBuffer();
 205   SourceMgr SM;
 206
 207   SM.AddNewSourceBuffer(&Buffer, SMLoc());
 208
 209   if (ByteArrayFromString(ByteArray, Str, SM)) {
 210     return -1;
 211   }
 212
 213   Triple T(TS);
 214   EDDisassembler::AssemblySyntax AS;
 215
 216   switch (T.getArch()) {
 217   default:
 218     errs() << "error: no default assembly syntax for " << TS.c_str() << "\n";
 219     return -1;
 220   case Triple::arm:
 221   case Triple::thumb:
 222     AS = EDDisassembler::kEDAssemblySyntaxARMUAL;
 223     break;
 224   case Triple::x86:
 225   case Triple::x86_64:
 226     AS = EDDisassembler::kEDAssemblySyntaxX86ATT;
 227     break;
 228   }
 229
 230   EDDisassembler::initialize();
 231   OwningPtr<EDDisassembler>
 232     disassembler(EDDisassembler::getDisassembler(TS.c_str(), AS));
 233
 234   if (disassembler == 0) {
 235     errs() << "error: couldn't get disassembler for " << TS << '\n';
 236     return -1;
 237   }
 238
 239   while (ByteArray.size()) {
 240     OwningPtr<EDInst>
 241       inst(disassembler->createInst(byteArrayReader, 0, &ByteArray));
 242
 243     if (inst == 0) {
 244       errs() << "error: Didn't get an instruction\n";
 245       return -1;
 246     }
 247
 248     ByteArray.erase (ByteArray.begin(), ByteArray.begin() + inst->byteSize());
 249
 250     unsigned numTokens = inst->numTokens();
 251     if ((int)numTokens < 0) {
 252       errs() << "error: couldn't count the instruction's tokens\n";
 253       return -1;
 254     }
 255
 256     for (unsigned tokenIndex = 0; tokenIndex != numTokens; ++tokenIndex) {
 257       EDToken *token;
 258
 259       if (inst->getToken(token, tokenIndex)) {
 260         errs() << "error: Couldn't get token\n";
 261         return -1;
 262       }
 263
 264       const char *buf;
 265       if (token->getString(buf)) {
 266         errs() << "error: Couldn't get string for token\n";
 267         return -1;
 268       }
 269
 270       Out << '[';
 271       int operandIndex = token->operandID();
 272
 273       if (operandIndex >= 0)
 274         Out << operandIndex << "-";
 275
 276       switch (token->type()) {
 277       default: Out << "?"; break;
 278       case EDToken::kTokenWhitespace: Out << "w"; break;
 279       case EDToken::kTokenPunctuation: Out << "p"; break;
 280       case EDToken::kTokenOpcode: Out << "o"; break;
 281       case EDToken::kTokenLiteral: Out << "l"; break;
 282       case EDToken::kTokenRegister: Out << "r"; break;
 283       }
 284
 285       Out << ":" << buf;
 286
 287       if (token->type() == EDToken::kTokenLiteral) {
 288         Out << "=";
 289         if (token->literalSign())
 290           Out << "-";
 291         uint64_t absoluteValue;
 292         if (token->literalAbsoluteValue(absoluteValue)) {
 293           errs() << "error: Couldn't get the value of a literal token\n";
 294           return -1;
 295         }
 296         Out << absoluteValue;
 297       } else if (token->type() == EDToken::kTokenRegister) {
 298         Out << "=";
 299         unsigned regID;
 300         if (token->registerID(regID)) {
 301           errs() << "error: Couldn't get the ID of a register token\n";
 302           return -1;
 303         }
 304         Out << "r" << regID;
 305       }
 306
 307       Out << "]";
 308     }
 309
 310     Out << " ";
 311
 312     if (inst->isBranch())
 313       Out << "<br> ";
 314     if (inst->isMove())
 315       Out << "<mov> ";
 316
 317     unsigned numOperands = inst->numOperands();
 318
 319     if ((int)numOperands < 0) {
 320       errs() << "error: Couldn't count operands\n";
 321       return -1;
 322     }
 323
 324     for (unsigned operandIndex = 0; operandIndex != numOperands;
 325          ++operandIndex) {
 326       Out << operandIndex << ":";
 327
 328       EDOperand *operand;
 329       if (inst->getOperand(operand, operandIndex)) {
 330         errs() << "error: couldn't get operand\n";
 331         return -1;
 332       }
 333
 334       uint64_t evaluatedResult;
 335       void *Arg[] = { disassembler.get(), &Out };
 336       if (operand->evaluate(evaluatedResult, verboseEvaluator, Arg)) {
 337         errs() << "error: Couldn't evaluate an operand\n";
 338         return -1;
 339       }
 340       Out << "=" << evaluatedResult << " ";
 341     }
 342
 343     Out << '\n';
 344   }
 345
 346   return 0;
 347 }
 348