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, const std::string &Triple,
 131                               MemoryBuffer &Buffer,
 132                               raw_ostream &Out) {
 133   // Set up disassembler.
 134   OwningPtr<const MCAsmInfo> AsmInfo(T.createAsmInfo(Triple));
 135
 136   if (!AsmInfo) {
 137     errs() << "error: no assembly info for target " << Triple << "\n";
 138     return -1;
 139   }
 140
 141   OwningPtr<const MCDisassembler> DisAsm(T.createMCDisassembler());
 142   if (!DisAsm) {
 143     errs() << "error: no disassembler for target " << Triple << "\n";
 144     return -1;
 145   }
 146
 147   int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
 148   OwningPtr<MCInstPrinter> IP(T.createMCInstPrinter(AsmPrinterVariant,
 149                                                     *AsmInfo));
 150   if (!IP) {
 151     errs() << "error: no instruction printer for target " << Triple << '\n';
 152     return -1;
 153   }
 154
 155   bool ErrorOccurred = false;
 156
 157   SourceMgr SM;
 158   SM.AddNewSourceBuffer(&Buffer, SMLoc());
 159
 160   // Convert the input to a vector for disassembly.
 161   ByteArrayTy ByteArray;
 162   StringRef Str = Buffer.getBuffer();
 163
 164   ErrorOccurred |= ByteArrayFromString(ByteArray, Str, SM);
 165
 166   if (!ByteArray.empty())
 167     ErrorOccurred |= PrintInsts(*DisAsm, *IP, ByteArray, SM, Out);
 168
 169   return ErrorOccurred;
 170 }
 171
 172 static int byteArrayReader(uint8_t *B, uint64_t A, void *Arg) {
 173   ByteArrayTy &ByteArray = *((ByteArrayTy*)Arg);
 174
 175   if (A >= ByteArray.size())
 176     return -1;
 177
 178   *B = ByteArray[A].first;
 179
 180   return 0;
 181 }
 182
 183 static int verboseEvaluator(uint64_t *V, unsigned R, void *Arg) {
 184   EDDisassembler &disassembler = *(EDDisassembler *)((void **)Arg)[0];
 185   raw_ostream &Out = *(raw_ostream *)((void **)Arg)[1];
 186
 187   if (const char *regName = disassembler.nameWithRegisterID(R))
 188     Out << "[" << regName << "/" << R << "]";
 189
 190   if (disassembler.registerIsStackPointer(R))
 191     Out << "(sp)";
 192   if (disassembler.registerIsProgramCounter(R))
 193     Out << "(pc)";
 194
 195   *V = 0;
 196   return 0;
 197 }
 198
 199 int Disassembler::disassembleEnhanced(const std::string &TS,
 200                                       MemoryBuffer &Buffer,
 201                                       raw_ostream &Out) {
 202   ByteArrayTy ByteArray;
 203   StringRef Str = Buffer.getBuffer();
 204   SourceMgr SM;
 205
 206   SM.AddNewSourceBuffer(&Buffer, SMLoc());
 207
 208   if (ByteArrayFromString(ByteArray, Str, SM)) {
 209     return -1;
 210   }
 211
 212   Triple T(TS);
 213   EDDisassembler::AssemblySyntax AS;
 214
 215   switch (T.getArch()) {
 216   default:
 217     errs() << "error: no default assembly syntax for " << TS.c_str() << "\n";
 218     return -1;
 219   case Triple::arm:
 220   case Triple::thumb:
 221     AS = EDDisassembler::kEDAssemblySyntaxARMUAL;
 222     break;
 223   case Triple::x86:
 224   case Triple::x86_64:
 225     AS = EDDisassembler::kEDAssemblySyntaxX86ATT;
 226     break;
 227   }
 228
 229   EDDisassembler::initialize();
 230   EDDisassembler *disassembler =
 231     EDDisassembler::getDisassembler(TS.c_str(), AS);
 232
 233   if (disassembler == 0) {
 234     errs() << "error: couldn't get disassembler for " << TS << '\n';
 235     return -1;
 236   }
 237
 238   EDInst *inst =
 239     disassembler->createInst(byteArrayReader, 0, &ByteArray);
 240
 241   if (inst == 0) {
 242     errs() << "error: Didn't get an instruction\n";
 243     return -1;
 244   }
 245
 246   unsigned numTokens = inst->numTokens();
 247   if ((int)numTokens < 0) {
 248     errs() << "error: couldn't count the instruction's tokens\n";
 249     return -1;
 250   }
 251
 252   for (unsigned tokenIndex = 0; tokenIndex != numTokens; ++tokenIndex) {
 253     EDToken *token;
 254
 255     if (inst->getToken(token, tokenIndex)) {
 256       errs() << "error: Couldn't get token\n";
 257       return -1;
 258     }
 259
 260     const char *buf;
 261     if (token->getString(buf)) {
 262       errs() << "error: Couldn't get string for token\n";
 263       return -1;
 264     }
 265
 266     Out << '[';
 267     int operandIndex = token->operandID();
 268
 269     if (operandIndex >= 0)
 270       Out << operandIndex << "-";
 271
 272     switch (token->type()) {
 273     default: Out << "?"; break;
 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; ++operandIndex) {
 321     Out << operandIndex << ":";
 322
 323     EDOperand *operand;
 324     if (inst->getOperand(operand, operandIndex)) {
 325       errs() << "error: couldn't get operand\n";
 326       return -1;
 327     }
 328
 329     uint64_t evaluatedResult;
 330     void *Arg[] = { disassembler, &Out };
 331     evaluatedResult = operand->evaluate(evaluatedResult, verboseEvaluator, Arg);
 332     Out << "=" << evaluatedResult << " ";
 333   }
 334
 335   Out << '\n';
 336
 337   return 0;
 338 }
 339