src/Binary.cxx

   1 #include "Binary.hxx"
   2
   3 #include "disassembler/Disassembler.hxx"
   4
   5 #include <iostream>
   6 #include <string>
   7 #include <algorithm>
   8
   9 #include "llvm/Support/raw_ostream.h"
  10
  11 using namespace llvm;
  12 using namespace llvm::object;
  13
  14 namespace {
  15     bool error(error_code ec) {
  16         if (!ec) return false;
  17
  18         outs() << "error reading file: " << ec.message() << ".\n";
  19         outs().flush();
  20         return true;
  21     }
  22
  23     bool RelocAddressLess(RelocationRef a, RelocationRef b) {
  24         uint64_t a_addr, b_addr;
  25         if (error(a.getOffset(a_addr))) return false;
  26         if (error(b.getOffset(b_addr))) return false;
  27         return a_addr < b_addr;
  28     }
  29
  30     void DumpBytes(StringRef bytes) {
  31         static const char hex_rep[] = "0123456789abcdef";
  32         // FIXME: The real way to do this is to figure out the longest instruction
  33         //        and align to that size before printing. I'll fix this when I get
  34         //        around to outputting relocations.
  35         // 15 is the longest x86 instruction
  36         // 3 is for the hex rep of a byte + a space.
  37         // 1 is for the null terminator.
  38         enum { OutputSize = (15 * 3) + 1 };
  39         char output[OutputSize];
  40
  41         assert(bytes.size() <= 15
  42                && "DumpBytes only supports instructions of up to 15 bytes");
  43         memset(output, ' ', sizeof(output));
  44         unsigned index = 0;
  45         for (StringRef::iterator i = bytes.begin(),
  46                  e = bytes.end(); i != e; ++i) {
  47             output[index] = hex_rep[(*i & 0xF0) >> 4];
  48             output[index + 1] = hex_rep[*i & 0xF];
  49             index += 3;
  50         }
  51
  52         output[sizeof(output) - 1] = 0;
  53         outs() << output;
  54     }
  55
  56     std::map<std::string, SectionRef> readSections(const ObjectFile& o) {
  57         error_code ec;
  58         std::map<std::string, SectionRef> result;
  59         section_iterator i(o.begin_sections()), e(o.end_sections());
  60         for (; i != e; i.increment(ec)) {
  61             StringRef name;
  62             if (error(i->getName(name))) break;
  63
  64             result.insert(make_pair(name.str(), *i));
  65         }
  66         return result;
  67     }
  68
  69     std::map<std::string, SymbolRef> readSymbols(const ObjectFile& o) {
  70         error_code ec;
  71         std::map<std::string, SymbolRef> result;
  72         symbol_iterator si(o.begin_symbols()), se(o.end_symbols());
  73         for (; si != se; si.increment(ec)) {
  74             StringRef name;
  75             if (error(si->getName(name))) break;
  76
  77             result.insert(make_pair(name.str(), *si));
  78         }
  79         return result;
  80     }
  81 }
  82
  83 namespace qtlldb {
  84
  85     Binary::Binary(const std::string& filename)
  86         : triple("unkown-unknown-unknown")
  87     {
  88         ::Disassembler d(filename);
  89         std::string error;
  90
  91         createBinary(filename, binary);
  92         if (Archive *a = dyn_cast<Archive>(binary.get())) {
  93             std::cerr << "Got an archive!" << std::endl;
  94             return;
  95         }
  96
  97         o = dyn_cast<ObjectFile>(binary.get());
  98
  99         triple.setArch(Triple::ArchType(o->getArch()));
 100         std::string tripleName(triple.getTriple());
 101
 102         outs() << tripleName << "\n";
 103
 104         target = TargetRegistry::lookupTarget("", triple, error);
 105         if (!target) {
 106             std::cerr << error;
 107             return;
 108         }
 109
 110         outs() << target->getName() << "\n";
 111
 112         MRI.reset(target->createMCRegInfo(tripleName));
 113         if (!MRI) {
 114             std::cerr << "error: no register info for target " << tripleName << "\n";
 115             return;
 116         }
 117
 118         // Set up disassembler.
 119         AsmInfo.reset(target->createMCAsmInfo(*MRI, tripleName));
 120         if (!AsmInfo) {
 121             std::cerr << "error: no assembly info for target " << tripleName << "\n";
 122             return;
 123         }
 124
 125         STI.reset(target->createMCSubtargetInfo(tripleName, "", ""));
 126         if (!STI) {
 127             errs() << "error: no subtarget info for target " << tripleName << "\n";
 128             return;
 129         }
 130
 131         MII.reset(target->createMCInstrInfo());
 132         if (!MII) {
 133             std::cerr << "error: no instruction info for target " << tripleName << "\n";
 134             return;
 135         }
 136
 137         DisAsm.reset(target->createMCDisassembler(*STI));
 138         if (!DisAsm) {
 139             std::cerr << "error: no disassembler for target " << tripleName << "\n";
 140             return;
 141         }
 142
 143         MOFI.reset(new MCObjectFileInfo);
 144         Ctx.reset(new MCContext(AsmInfo.get(), MRI.get(), MOFI.get()));
 145         RelInfo.reset(
 146             target->createMCRelocationInfo(tripleName, *Ctx.get()));
 147         if (RelInfo) {
 148             Symzer.reset(
 149                 MCObjectSymbolizer::createObjectSymbolizer(*Ctx.get(), RelInfo, o));
 150             if (Symzer)
 151                 DisAsm->setSymbolizer(Symzer);
 152         }
 153
 154         MIA.reset(target->createMCInstrAnalysis(MII.get()));
 155
 156         int AsmPrinterVariant = AsmInfo->getAssemblerDialect();
 157         IP.reset(target->createMCInstPrinter(AsmPrinterVariant, *AsmInfo, *MII, *MRI, *STI));
 158         if (!IP) {
 159             std::cerr << "error: no instruction printer for target " << tripleName
 160                       << '\n';
 161             return;
 162         }
 163
 164         OwningPtr<MCObjectDisassembler> OD(
 165             new MCObjectDisassembler(*o, *DisAsm, *MIA));
 166         Mod.reset(OD->buildModule(/* withCFG */ false));
 167
 168         symbols = readSymbols(*o);
 169         sections = readSections(*o);
 170
 171         // for_each(sections.begin(), sections.end(), [](const std::pair<std::string, SectionRef>& i){
 172         //         std::cout << "Section: " << i.first << std::endl;
 173         //     });
 174     }
 175
 176
 177
 178     std::vector<std::string> Binary::getSymbols() {
 179         error_code ec;
 180         SectionRef r = sections[".text"];
 181         std::vector<std::string> result;
 182         for_each(symbols.begin(), symbols.end(), [&](const std::pair<std::string, SymbolRef>& i) {
 183                      bool contains;
 184                      if (!error(r.containsSymbol(i.second, contains)) && contains)
 185                          result.push_back(i.first);
 186                  });
 187         return result;
 188     }
 189
 190     void Binary::for_each_instruction(const std::string& function,
 191                                       std::function<void (long, std::string, std::string)> callback) {
 192         StringRef bytes;
 193         uint64_t base_address, address, ssize, size(0), index, end;
 194         StringRefMemoryObject memoryObject("");
 195
 196         if (symbols.end() != symbols.find(function)) {
 197             SymbolRef ref;
 198             section_iterator sec(o->begin_sections());
 199
 200             ref = symbols.at(function);
 201             if (error(ref.getSection(sec))) return;
 202             if (error(ref.getAddress(address))) return;
 203             if (address == UnknownAddressOrSize) return;
 204             if (error(ref.getSize(ssize))) return;
 205             if (error(sec->getAddress(base_address))) return;
 206             if (error(sec->getContents(bytes))) return;
 207             memoryObject = bytes;
 208
 209         }
 210         else if (sections.end() != sections.find(function)) {
 211             SectionRef sref = sections.at(function);
 212             if (error(sref.getAddress(address))) return;
 213             if (address == UnknownAddressOrSize) return;
 214             if (error(sref.getSize(ssize))) return;
 215             if (error(sref.getContents(bytes))) return;
 216             base_address = address;
 217             memoryObject = bytes;
 218         }
 219
 220
 221         // outs() << "Start for_each_instruction " << function << "\n";
 222
 223
 224         for (end = address + ssize - base_address, index = address - base_address; index < end; index += size) {
 225             MCInst Inst;
 226
 227             if (DisAsm->getInstruction(Inst, size, memoryObject, index,
 228                                        nulls(), nulls())) {
 229                 std::string buf;
 230                 llvm::raw_string_ostream s(buf);
 231                 IP->printInst(&Inst, s, "");
 232
 233                 if (index + size < bytes.str().length())
 234                     callback(base_address + index, bytes.str().substr(index, size), s.str());
 235
 236             } else {
 237                 errs() << "warning: invalid instruction encoding\n";
 238                 if (size == 0)
 239                     size = 1; // skip illegible bytes
 240             }
 241         }
 242         // outs() << "End for_each_instruction\n";
 243
 244     }
 245
 246     void Binary::disassemble() {
 247         for (MCModule::const_atom_iterator AI = Mod->atom_begin(),
 248                  AE = Mod->atom_end();
 249              AI != AE; ++AI) {
 250
 251             if ((*AI)->getKind() != llvm::MCAtom::TextAtom)
 252                 continue;
 253
 254             outs() << "\n\nAtom " << (*AI)->getName() << ": \n";
 255             if (const MCTextAtom *TA = dyn_cast<MCTextAtom>(*AI)) {
 256                 for (MCTextAtom::const_iterator II = TA->begin(), IE = TA->end();
 257                      II != IE;
 258                      ++II) {
 259 //                II->Inst.dump();
 260                     IP->printInst(&II->Inst, outs(), "");
 261                     outs() << "\n";
 262                 }
 263             }
 264         }
 265
 266         outs() << "binary " << triple.getArchName() << "\n";
 267     }
 268
 269     void Binary::disassemble_functions() {
 270         error_code ec;
 271         for (section_iterator i = o->begin_sections(),
 272                  e = o->end_sections();
 273              i != e; i.increment(ec)) {
 274             if (error(ec)) break;
 275             bool text;
 276             if (error(i->isText(text))) break;
 277             if (!text) continue;
 278
 279             uint64_t SectionAddr;
 280             if (error(i->getAddress(SectionAddr))) break;
 281
 282             // Make a list of all the symbols in this section.
 283             std::vector<std::pair<uint64_t, StringRef> > Symbols;
 284             for (symbol_iterator si = o->begin_symbols(),
 285                      se = o->end_symbols();
 286                  si != se; si.increment(ec)) {
 287                 bool contains;
 288                 if (!error(i->containsSymbol(*si, contains)) && contains) {
 289                     uint64_t Address;
 290                     if (error(si->getAddress(Address))) break;
 291                     if (Address == UnknownAddressOrSize) continue;
 292                     Address -= SectionAddr;
 293
 294                     StringRef Name;
 295                     if (error(si->getName(Name))) break;
 296
 297                     outs() << "\nXXX " << Name << "\n";
 298
 299                     Symbols.push_back(std::make_pair(Address, Name));
 300                 }
 301             }
 302
 303             // Sort the symbols by address, just in case they didn't come in that way.
 304             array_pod_sort(Symbols.begin(), Symbols.end());
 305
 306             // Make a list of all the relocations for this section.
 307             std::vector<RelocationRef> Rels;
 308             // if (InlineRelocs) {
 309             //     for (relocation_iterator ri = i->begin_relocations(),
 310             //              re = i->end_relocations();
 311             //          ri != re; ri.increment(ec)) {
 312             //         if (error(ec)) break;
 313             //         Rels.push_back(*ri);
 314             //     }
 315             // }
 316
 317             // Sort relocations by address.
 318             std::sort(Rels.begin(), Rels.end(), RelocAddressLess);
 319
 320             StringRef SegmentName = "";
 321             // if (const MachOObjectFile *MachO =
 322             //     dyn_cast<const MachOObjectFile>(o)) {
 323             //     DataRefImpl DR = i->getRawDataRefImpl();
 324             //     SegmentName = MachO->getSectionFinalSegmentName(DR);
 325             // }
 326             StringRef name;
 327             if (error(i->getName(name))) break;
 328             outs() << "Disassembly of section ";
 329             if (!SegmentName.empty())
 330                 outs() << SegmentName << ",";
 331             outs() << name << ':';
 332
 333             // If the section has no symbols just insert a dummy one and disassemble
 334             // the whole section.
 335             if (Symbols.empty())
 336                 Symbols.push_back(std::make_pair(0, name));
 337
 338
 339             StringRef Bytes;
 340             if (error(i->getContents(Bytes))) break;
 341             StringRefMemoryObject memoryObject(Bytes);
 342             uint64_t Size;
 343             uint64_t Index;
 344             uint64_t SectSize;
 345             if (error(i->getSize(SectSize))) break;
 346
 347             std::vector<RelocationRef>::const_iterator rel_cur = Rels.begin();
 348             std::vector<RelocationRef>::const_iterator rel_end = Rels.end();
 349             // Disassemble symbol by symbol.
 350             for (unsigned si = 0, se = Symbols.size(); si != se; ++si) {
 351                 uint64_t Start = Symbols[si].first;
 352                 uint64_t End;
 353                 // The end is either the size of the section or the beginning of the next
 354                 // symbol.
 355                 if (si == se - 1)
 356                     End = SectSize;
 357                 // Make sure this symbol takes up space.
 358                 else if (Symbols[si + 1].first != Start)
 359                     End = Symbols[si + 1].first - 1;
 360                 else
 361                     // This symbol has the same address as the next symbol. Skip it.
 362                     continue;
 363
 364                 outs() << '\n' << Symbols[si].second << ":\n";
 365
 366 #ifndef NDEBUG
 367                 raw_ostream &DebugOut = DebugFlag ? dbgs() : nulls();
 368 #else
 369                 raw_ostream &DebugOut = nulls();
 370 #endif
 371
 372                 for (Index = Start; Index < End; Index += Size) {
 373                     MCInst Inst;
 374
 375                     if (DisAsm->getInstruction(Inst, Size, memoryObject, Index,
 376                                                DebugOut, nulls())) {
 377                         outs() << format("%8" PRIx64 ":", SectionAddr + Index);
 378                         outs() << "\t";
 379                         DumpBytes(StringRef(Bytes.data() + Index, Size));
 380
 381                         IP->printInst(&Inst, outs(), "");
 382                         outs() << "\n";
 383                     } else {
 384                         errs() << "warning: invalid instruction encoding\n";
 385                         if (Size == 0)
 386                             Size = 1; // skip illegible bytes
 387                     }
 388
 389                     // Print relocation for instruction.
 390                     while (rel_cur != rel_end) {
 391                         bool hidden = false;
 392                         uint64_t addr;
 393                         SmallString<16> name;
 394                         SmallString<32> val;
 395
 396                         // If this relocation is hidden, skip it.
 397                         if (error(rel_cur->getHidden(hidden))) goto skip_print_rel;
 398                         if (hidden) goto skip_print_rel;
 399
 400                         if (error(rel_cur->getOffset(addr))) goto skip_print_rel;
 401                         // Stop when rel_cur's address is past the current instruction.
 402                         if (addr >= Index + Size) break;
 403                         if (error(rel_cur->getTypeName(name))) goto skip_print_rel;
 404                         if (error(rel_cur->getValueString(val))) goto skip_print_rel;
 405
 406                         outs() << format("\t\t\t%8" PRIx64 ": ", SectionAddr + addr) << name
 407                                << "\t" << val << "\n";
 408
 409                       skip_print_rel:
 410                         ++rel_cur;
 411                     }
 412                 }
 413             }
 414         }
 415     }
 416
 417     void Binary::disassemble_cfg() {
 418         for (MCModule::const_func_iterator FI = Mod->func_begin(),
 419                  FE = Mod->func_end();
 420              FI != FE; ++FI) {
 421             static int filenum = 0;
 422             std::string FileName = std::string("dot/") + (Twine((*FI)->getName()) + "_" + utostr(filenum) + ".dot").str();
 423
 424             std::cerr << FileName << std::endl;
 425
 426             // Start a new dot file.
 427             std::string Error;
 428             raw_fd_ostream Out(FileName.c_str(), Error);
 429             if (!Error.empty()) {
 430                 errs() << "llvm-objdump: warning: " << Error << '\n';
 431                 return;
 432             }
 433
 434             Out << "digraph \"" << (*FI)->getName() << "\" {\n";
 435             Out << "graph [ rankdir = \"LR\" ];\n";
 436             for (MCFunction::const_iterator i = (*FI)->begin(), e = (*FI)->end(); i != e; ++i) {
 437                 // Only print blocks that have predecessors.
 438                 bool hasPreds = (*i)->pred_begin() != (*i)->pred_end();
 439
 440                 if (!hasPreds && i != (*FI)->begin())
 441                     continue;
 442
 443                 Out << '"' << (*i)->getInsts()->getBeginAddr() << "\" [ label=\"<a>";
 444                 // Print instructions.
 445                 for (unsigned ii = 0, ie = (*i)->getInsts()->size(); ii != ie;
 446                      ++ii) {
 447                     if (ii != 0) // Not the first line, start a new row.
 448                         Out << '|';
 449                     if (ii + 1 == ie) // Last line, add an end id.
 450                         Out << "<o>";
 451
 452                     // Escape special chars and print the instruction in mnemonic form.
 453                     std::string Str;
 454                     raw_string_ostream OS(Str);
 455                     IP->printInst(&(*i)->getInsts()->at(ii).Inst, OS, "");
 456                     Out << DOT::EscapeString(OS.str());
 457                 }
 458                 Out << "\" shape=\"record\" ];\n";
 459
 460                 // Add edges.
 461                 for (MCBasicBlock::succ_const_iterator si = (*i)->succ_begin(),
 462                          se = (*i)->succ_end(); si != se; ++si)
 463                     Out << (*i)->getInsts()->getBeginAddr() << ":o -> "
 464                         << (*si)->getInsts()->getBeginAddr() << ":a\n";
 465             }
 466             Out << "}\n";
 467
 468             ++filenum;
 469         }
 470     }
 471 }