lib/MC/MCDisassembler/EDDisassembler.cpp

   1 //===-EDDisassembler.cpp - LLVM Enhanced Disassembler ---------------------===//
   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 file implements the Enhanced Disassembly library's  disassembler class.
  11 // The disassembler is responsible for vending individual instructions according
  12 // to a given architecture and disassembly syntax.
  13 //
  14 //===----------------------------------------------------------------------===//
  15
  16 #include "EDDisassembler.h"
  17 #include "EDInst.h"
  18 #include "llvm/MC/EDInstInfo.h"
  19 #include "llvm/MC/MCAsmInfo.h"
  20 #include "llvm/MC/MCContext.h"
  21 #include "llvm/MC/MCDisassembler.h"
  22 #include "llvm/MC/MCExpr.h"
  23 #include "llvm/MC/MCInst.h"
  24 #include "llvm/MC/MCInstPrinter.h"
  25 #include "llvm/MC/MCStreamer.h"
  26 #include "llvm/MC/MCParser/AsmLexer.h"
  27 #include "llvm/MC/MCParser/MCAsmParser.h"
  28 #include "llvm/MC/MCParser/MCParsedAsmOperand.h"
  29 #include "llvm/Support/MemoryBuffer.h"
  30 #include "llvm/Support/MemoryObject.h"
  31 #include "llvm/Support/SourceMgr.h"
  32 #include "llvm/Target/TargetAsmLexer.h"
  33 #include "llvm/Target/TargetAsmParser.h"
  34 #include "llvm/Target/TargetRegistry.h"
  35 #include "llvm/Target/TargetMachine.h"
  36 #include "llvm/Target/TargetRegisterInfo.h"
  37 #include "llvm/Target/TargetSelect.h"
  38 using namespace llvm;
  39
  40 bool EDDisassembler::sInitialized = false;
  41 EDDisassembler::DisassemblerMap_t EDDisassembler::sDisassemblers;
  42
  43 struct TripleMap {
  44   Triple::ArchType Arch;
  45   const char *String;
  46 };
  47
  48 static struct TripleMap triplemap[] = {
  49   { Triple::x86,          "i386-unknown-unknown"    },
  50   { Triple::x86_64,       "x86_64-unknown-unknown"  },
  51   { Triple::arm,          "arm-unknown-unknown"     },
  52   { Triple::thumb,        "thumb-unknown-unknown"   },
  53   { Triple::InvalidArch,  NULL,                     }
  54 };
  55
  56 /// infoFromArch - Returns the TripleMap corresponding to a given architecture,
  57 ///   or NULL if there is an error
  58 ///
  59 /// @arg arch - The Triple::ArchType for the desired architecture
  60 static const char *tripleFromArch(Triple::ArchType arch) {
  61   unsigned int infoIndex;
  62
  63   for (infoIndex = 0; triplemap[infoIndex].String != NULL; ++infoIndex) {
  64     if (arch == triplemap[infoIndex].Arch)
  65       return triplemap[infoIndex].String;
  66   }
  67
  68   return NULL;
  69 }
  70
  71 /// getLLVMSyntaxVariant - gets the constant to use to get an assembly printer
  72 ///   for the desired assembly syntax, suitable for passing to
  73 ///   Target::createMCInstPrinter()
  74 ///
  75 /// @arg arch   - The target architecture
  76 /// @arg syntax - The assembly syntax in sd form
  77 static int getLLVMSyntaxVariant(Triple::ArchType arch,
  78                                 EDDisassembler::AssemblySyntax syntax) {
  79   switch (syntax) {
  80   default:
  81     return -1;
  82   // Mappings below from X86AsmPrinter.cpp
  83   case EDDisassembler::kEDAssemblySyntaxX86ATT:
  84     if (arch == Triple::x86 || arch == Triple::x86_64)
  85       return 0;
  86     else
  87       return -1;
  88   case EDDisassembler::kEDAssemblySyntaxX86Intel:
  89     if (arch == Triple::x86 || arch == Triple::x86_64)
  90       return 1;
  91     else
  92       return -1;
  93   case EDDisassembler::kEDAssemblySyntaxARMUAL:
  94     if (arch == Triple::arm || arch == Triple::thumb)
  95       return 0;
  96     else
  97       return -1;
  98   }
  99 }
 100
 101 void EDDisassembler::initialize() {
 102   if (sInitialized)
 103     return;
 104
 105   sInitialized = true;
 106
 107   InitializeAllTargetInfos();
 108   InitializeAllTargets();
 109   InitializeAllAsmPrinters();
 110   InitializeAllAsmParsers();
 111   InitializeAllDisassemblers();
 112 }
 113
 114 #undef BRINGUP_TARGET
 115
 116 EDDisassembler *EDDisassembler::getDisassembler(Triple::ArchType arch,
 117                                                 AssemblySyntax syntax) {
 118   CPUKey key;
 119   key.Arch = arch;
 120   key.Syntax = syntax;
 121
 122   EDDisassembler::DisassemblerMap_t::iterator i = sDisassemblers.find(key);
 123
 124   if (i != sDisassemblers.end()) {
 125     return i->second;
 126   } else {
 127     EDDisassembler* sdd = new EDDisassembler(key);
 128     if (!sdd->valid()) {
 129       delete sdd;
 130       return NULL;
 131     }
 132
 133     sDisassemblers[key] = sdd;
 134
 135     return sdd;
 136   }
 137
 138   return NULL;
 139 }
 140
 141 EDDisassembler *EDDisassembler::getDisassembler(StringRef str,
 142                                                 AssemblySyntax syntax) {
 143   return getDisassembler(Triple(str).getArch(), syntax);
 144 }
 145
 146 EDDisassembler::EDDisassembler(CPUKey &key) :
 147   Valid(false),
 148   HasSemantics(false),
 149   ErrorStream(nulls()),
 150   Key(key) {
 151   const char *triple = tripleFromArch(key.Arch);
 152
 153   if (!triple)
 154     return;
 155
 156   LLVMSyntaxVariant = getLLVMSyntaxVariant(key.Arch, key.Syntax);
 157
 158   if (LLVMSyntaxVariant < 0)
 159     return;
 160
 161   std::string tripleString(triple);
 162   std::string errorString;
 163
 164   Tgt = TargetRegistry::lookupTarget(tripleString,
 165                                      errorString);
 166
 167   if (!Tgt)
 168     return;
 169
 170   std::string featureString;
 171
 172   TargetMachine.reset(Tgt->createTargetMachine(tripleString,
 173                                                featureString));
 174
 175   const TargetRegisterInfo *registerInfo = TargetMachine->getRegisterInfo();
 176
 177   if (!registerInfo)
 178     return;
 179
 180   initMaps(*registerInfo);
 181
 182   AsmInfo.reset(Tgt->createAsmInfo(tripleString));
 183
 184   if (!AsmInfo)
 185     return;
 186
 187   Disassembler.reset(Tgt->createMCDisassembler());
 188
 189   if (!Disassembler)
 190     return;
 191
 192   InstInfos = Disassembler->getEDInfo();
 193
 194   InstString.reset(new std::string);
 195   InstStream.reset(new raw_string_ostream(*InstString));
 196   InstPrinter.reset(Tgt->createMCInstPrinter(*TargetMachine, LLVMSyntaxVariant,
 197                                              *AsmInfo));
 198
 199   if (!InstPrinter)
 200     return;
 201
 202   GenericAsmLexer.reset(new AsmLexer(*AsmInfo));
 203   SpecificAsmLexer.reset(Tgt->createAsmLexer(*AsmInfo));
 204   SpecificAsmLexer->InstallLexer(*GenericAsmLexer);
 205
 206   initMaps(*TargetMachine->getRegisterInfo());
 207
 208   Valid = true;
 209 }
 210
 211 EDDisassembler::~EDDisassembler() {
 212   if (!valid())
 213     return;
 214 }
 215
 216 namespace {
 217   /// EDMemoryObject - a subclass of MemoryObject that allows use of a callback
 218   ///   as provided by the sd interface.  See MemoryObject.
 219   class EDMemoryObject : public llvm::MemoryObject {
 220   private:
 221     EDByteReaderCallback Callback;
 222     void *Arg;
 223   public:
 224     EDMemoryObject(EDByteReaderCallback callback,
 225                    void *arg) : Callback(callback), Arg(arg) { }
 226     ~EDMemoryObject() { }
 227     uint64_t getBase() const { return 0x0; }
 228     uint64_t getExtent() const { return (uint64_t)-1; }
 229     int readByte(uint64_t address, uint8_t *ptr) const {
 230       if (!Callback)
 231         return -1;
 232
 233       if (Callback(ptr, address, Arg))
 234         return -1;
 235
 236       return 0;
 237     }
 238   };
 239 }
 240
 241 EDInst *EDDisassembler::createInst(EDByteReaderCallback byteReader,
 242                                    uint64_t address,
 243                                    void *arg) {
 244   EDMemoryObject memoryObject(byteReader, arg);
 245
 246   MCInst* inst = new MCInst;
 247   uint64_t byteSize;
 248
 249   if (!Disassembler->getInstruction(*inst,
 250                                     byteSize,
 251                                     memoryObject,
 252                                     address,
 253                                     ErrorStream)) {
 254     delete inst;
 255     return NULL;
 256   } else {
 257     const llvm::EDInstInfo *thisInstInfo;
 258
 259     thisInstInfo = &InstInfos[inst->getOpcode()];
 260
 261     EDInst* sdInst = new EDInst(inst, byteSize, *this, thisInstInfo);
 262     return sdInst;
 263   }
 264 }
 265
 266 void EDDisassembler::initMaps(const TargetRegisterInfo &registerInfo) {
 267   unsigned numRegisters = registerInfo.getNumRegs();
 268   unsigned registerIndex;
 269
 270   for (registerIndex = 0; registerIndex < numRegisters; ++registerIndex) {
 271     const char* registerName = registerInfo.get(registerIndex).Name;
 272
 273     RegVec.push_back(registerName);
 274     RegRMap[registerName] = registerIndex;
 275   }
 276
 277   switch (Key.Arch) {
 278   default:
 279     break;
 280   case Triple::x86:
 281   case Triple::x86_64:
 282     stackPointers.insert(registerIDWithName("SP"));
 283     stackPointers.insert(registerIDWithName("ESP"));
 284     stackPointers.insert(registerIDWithName("RSP"));
 285
 286     programCounters.insert(registerIDWithName("IP"));
 287     programCounters.insert(registerIDWithName("EIP"));
 288     programCounters.insert(registerIDWithName("RIP"));
 289     break;
 290   case Triple::arm:
 291   case Triple::thumb:
 292     stackPointers.insert(registerIDWithName("SP"));
 293
 294     programCounters.insert(registerIDWithName("PC"));
 295     break;
 296   }
 297 }
 298
 299 const char *EDDisassembler::nameWithRegisterID(unsigned registerID) const {
 300   if (registerID >= RegVec.size())
 301     return NULL;
 302   else
 303     return RegVec[registerID].c_str();
 304 }
 305
 306 unsigned EDDisassembler::registerIDWithName(const char *name) const {
 307   regrmap_t::const_iterator iter = RegRMap.find(std::string(name));
 308   if (iter == RegRMap.end())
 309     return 0;
 310   else
 311     return (*iter).second;
 312 }
 313
 314 bool EDDisassembler::registerIsStackPointer(unsigned registerID) {
 315   return (stackPointers.find(registerID) != stackPointers.end());
 316 }
 317
 318 bool EDDisassembler::registerIsProgramCounter(unsigned registerID) {
 319   return (programCounters.find(registerID) != programCounters.end());
 320 }
 321
 322 int EDDisassembler::printInst(std::string &str, MCInst &inst) {
 323   PrinterMutex.acquire();
 324
 325   InstPrinter->printInst(&inst, *InstStream);
 326   InstStream->flush();
 327   str = *InstString;
 328   InstString->clear();
 329
 330   PrinterMutex.release();
 331
 332   return 0;
 333 }
 334
 335 int EDDisassembler::parseInst(SmallVectorImpl<MCParsedAsmOperand*> &operands,
 336                               SmallVectorImpl<AsmToken> &tokens,
 337                               const std::string &str) {
 338   int ret = 0;
 339
 340   switch (Key.Arch) {
 341   default:
 342     return -1;
 343   case Triple::x86:
 344   case Triple::x86_64:
 345   case Triple::arm:
 346   case Triple::thumb:
 347     break;
 348   }
 349
 350   const char *cStr = str.c_str();
 351   MemoryBuffer *buf = MemoryBuffer::getMemBuffer(cStr, cStr + strlen(cStr));
 352
 353   StringRef instName;
 354   SMLoc instLoc;
 355
 356   SourceMgr sourceMgr;
 357   sourceMgr.AddNewSourceBuffer(buf, SMLoc()); // ownership of buf handed over
 358   MCContext context(*AsmInfo, NULL);
 359   OwningPtr<MCStreamer> streamer(createNullStreamer(context));
 360   OwningPtr<MCAsmParser> genericParser(createMCAsmParser(*Tgt, sourceMgr,
 361                                                          context, *streamer,
 362                                                          *AsmInfo));
 363   OwningPtr<TargetAsmParser> TargetParser(Tgt->createAsmParser(*genericParser,
 364                                                                *TargetMachine));
 365
 366   AsmToken OpcodeToken = genericParser->Lex();
 367   AsmToken NextToken = genericParser->Lex();  // consume next token, because specificParser expects us to
 368
 369   if (OpcodeToken.is(AsmToken::Identifier)) {
 370     instName = OpcodeToken.getString();
 371     instLoc = OpcodeToken.getLoc();
 372
 373     if (NextToken.isNot(AsmToken::Eof) &&
 374         TargetParser->ParseInstruction(instName, instLoc, operands))
 375       ret = -1;
 376   } else {
 377     ret = -1;
 378   }
 379
 380   ParserMutex.acquire();
 381
 382   if (!ret) {
 383     GenericAsmLexer->setBuffer(buf);
 384
 385     while (SpecificAsmLexer->Lex(),
 386            SpecificAsmLexer->isNot(AsmToken::Eof) &&
 387            SpecificAsmLexer->isNot(AsmToken::EndOfStatement)) {
 388       if (SpecificAsmLexer->is(AsmToken::Error)) {
 389         ret = -1;
 390         break;
 391       }
 392       tokens.push_back(SpecificAsmLexer->getTok());
 393     }
 394   }
 395
 396   ParserMutex.release();
 397
 398   return ret;
 399 }
 400
 401 int EDDisassembler::llvmSyntaxVariant() const {
 402   return LLVMSyntaxVariant;
 403 }