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      1 //===-- llvm-nm.cpp - Symbol table dumping utility for llvm ---------------===//
      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 program is a utility that works like traditional Unix "nm", that is, it
     11 // prints out the names of symbols in a bitcode or object file, along with some
     12 // information about each symbol.
     13 //
     14 // This "nm" supports many of the features of GNU "nm", including its different
     15 // output formats.
     16 //
     17 //===----------------------------------------------------------------------===//
     18 
     19 #include "llvm/IR/Function.h"
     20 #include "llvm/IR/GlobalAlias.h"
     21 #include "llvm/IR/GlobalVariable.h"
     22 #include "llvm/IR/LLVMContext.h"
     23 #include "llvm/Object/Archive.h"
     24 #include "llvm/Object/COFF.h"
     25 #include "llvm/Object/ELFObjectFile.h"
     26 #include "llvm/Object/IRObjectFile.h"
     27 #include "llvm/Object/MachO.h"
     28 #include "llvm/Object/MachOUniversal.h"
     29 #include "llvm/Object/ObjectFile.h"
     30 #include "llvm/Support/COFF.h"
     31 #include "llvm/Support/CommandLine.h"
     32 #include "llvm/Support/FileSystem.h"
     33 #include "llvm/Support/Format.h"
     34 #include "llvm/Support/ManagedStatic.h"
     35 #include "llvm/Support/MemoryBuffer.h"
     36 #include "llvm/Support/PrettyStackTrace.h"
     37 #include "llvm/Support/Program.h"
     38 #include "llvm/Support/Signals.h"
     39 #include "llvm/Support/raw_ostream.h"
     40 #include "llvm/Support/TargetSelect.h"
     41 #include <algorithm>
     42 #include <cctype>
     43 #include <cerrno>
     44 #include <cstring>
     45 #include <system_error>
     46 #include <vector>
     47 using namespace llvm;
     48 using namespace object;
     49 
     50 namespace {
     51 enum OutputFormatTy { bsd, sysv, posix, darwin };
     52 cl::opt<OutputFormatTy> OutputFormat(
     53     "format", cl::desc("Specify output format"),
     54     cl::values(clEnumVal(bsd, "BSD format"), clEnumVal(sysv, "System V format"),
     55                clEnumVal(posix, "POSIX.2 format"),
     56                clEnumVal(darwin, "Darwin -m format"), clEnumValEnd),
     57     cl::init(bsd));
     58 cl::alias OutputFormat2("f", cl::desc("Alias for --format"),
     59                         cl::aliasopt(OutputFormat));
     60 
     61 cl::list<std::string> InputFilenames(cl::Positional, cl::desc("<input files>"),
     62                                      cl::ZeroOrMore);
     63 
     64 cl::opt<bool> UndefinedOnly("undefined-only",
     65                             cl::desc("Show only undefined symbols"));
     66 cl::alias UndefinedOnly2("u", cl::desc("Alias for --undefined-only"),
     67                          cl::aliasopt(UndefinedOnly));
     68 
     69 cl::opt<bool> DynamicSyms("dynamic",
     70                           cl::desc("Display the dynamic symbols instead "
     71                                    "of normal symbols."));
     72 cl::alias DynamicSyms2("D", cl::desc("Alias for --dynamic"),
     73                        cl::aliasopt(DynamicSyms));
     74 
     75 cl::opt<bool> DefinedOnly("defined-only",
     76                           cl::desc("Show only defined symbols"));
     77 cl::alias DefinedOnly2("U", cl::desc("Alias for --defined-only"),
     78                        cl::aliasopt(DefinedOnly));
     79 
     80 cl::opt<bool> ExternalOnly("extern-only",
     81                            cl::desc("Show only external symbols"));
     82 cl::alias ExternalOnly2("g", cl::desc("Alias for --extern-only"),
     83                         cl::aliasopt(ExternalOnly));
     84 
     85 cl::opt<bool> BSDFormat("B", cl::desc("Alias for --format=bsd"));
     86 cl::opt<bool> POSIXFormat("P", cl::desc("Alias for --format=posix"));
     87 cl::opt<bool> DarwinFormat("m", cl::desc("Alias for --format=darwin"));
     88 
     89 static cl::list<std::string>
     90 ArchFlags("arch", cl::desc("architecture(s) from a Mach-O file to dump"),
     91           cl::ZeroOrMore);
     92 bool ArchAll = false;
     93 
     94 cl::opt<bool> PrintFileName(
     95     "print-file-name",
     96     cl::desc("Precede each symbol with the object file it came from"));
     97 
     98 cl::alias PrintFileNameA("A", cl::desc("Alias for --print-file-name"),
     99                          cl::aliasopt(PrintFileName));
    100 cl::alias PrintFileNameo("o", cl::desc("Alias for --print-file-name"),
    101                          cl::aliasopt(PrintFileName));
    102 
    103 cl::opt<bool> DebugSyms("debug-syms",
    104                         cl::desc("Show all symbols, even debugger only"));
    105 cl::alias DebugSymsa("a", cl::desc("Alias for --debug-syms"),
    106                      cl::aliasopt(DebugSyms));
    107 
    108 cl::opt<bool> NumericSort("numeric-sort", cl::desc("Sort symbols by address"));
    109 cl::alias NumericSortn("n", cl::desc("Alias for --numeric-sort"),
    110                        cl::aliasopt(NumericSort));
    111 cl::alias NumericSortv("v", cl::desc("Alias for --numeric-sort"),
    112                        cl::aliasopt(NumericSort));
    113 
    114 cl::opt<bool> NoSort("no-sort", cl::desc("Show symbols in order encountered"));
    115 cl::alias NoSortp("p", cl::desc("Alias for --no-sort"), cl::aliasopt(NoSort));
    116 
    117 cl::opt<bool> ReverseSort("reverse-sort", cl::desc("Sort in reverse order"));
    118 cl::alias ReverseSortr("r", cl::desc("Alias for --reverse-sort"),
    119                        cl::aliasopt(ReverseSort));
    120 
    121 cl::opt<bool> PrintSize("print-size",
    122                         cl::desc("Show symbol size instead of address"));
    123 cl::alias PrintSizeS("S", cl::desc("Alias for --print-size"),
    124                      cl::aliasopt(PrintSize));
    125 
    126 cl::opt<bool> SizeSort("size-sort", cl::desc("Sort symbols by size"));
    127 
    128 cl::opt<bool> WithoutAliases("without-aliases", cl::Hidden,
    129                              cl::desc("Exclude aliases from output"));
    130 
    131 cl::opt<bool> ArchiveMap("print-armap", cl::desc("Print the archive map"));
    132 cl::alias ArchiveMaps("M", cl::desc("Alias for --print-armap"),
    133                       cl::aliasopt(ArchiveMap));
    134 
    135 cl::opt<bool> JustSymbolName("just-symbol-name",
    136                              cl::desc("Print just the symbol's name"));
    137 cl::alias JustSymbolNames("j", cl::desc("Alias for --just-symbol-name"),
    138                           cl::aliasopt(JustSymbolName));
    139 bool PrintAddress = true;
    140 
    141 bool MultipleFiles = false;
    142 
    143 bool HadError = false;
    144 
    145 std::string ToolName;
    146 }
    147 
    148 static void error(Twine Message, Twine Path = Twine()) {
    149   HadError = true;
    150   errs() << ToolName << ": " << Path << ": " << Message << ".\n";
    151 }
    152 
    153 static bool error(std::error_code EC, Twine Path = Twine()) {
    154   if (EC) {
    155     error(EC.message(), Path);
    156     return true;
    157   }
    158   return false;
    159 }
    160 
    161 namespace {
    162 struct NMSymbol {
    163   uint64_t Address;
    164   uint64_t Size;
    165   char TypeChar;
    166   StringRef Name;
    167   DataRefImpl Symb;
    168 };
    169 }
    170 
    171 static bool compareSymbolAddress(const NMSymbol &A, const NMSymbol &B) {
    172   if (!ReverseSort) {
    173     if (A.Address < B.Address)
    174       return true;
    175     else if (A.Address == B.Address && A.Name < B.Name)
    176       return true;
    177     else if (A.Address == B.Address && A.Name == B.Name && A.Size < B.Size)
    178       return true;
    179     else
    180       return false;
    181   } else {
    182     if (A.Address > B.Address)
    183       return true;
    184     else if (A.Address == B.Address && A.Name > B.Name)
    185       return true;
    186     else if (A.Address == B.Address && A.Name == B.Name && A.Size > B.Size)
    187       return true;
    188     else
    189       return false;
    190   }
    191 }
    192 
    193 static bool compareSymbolSize(const NMSymbol &A, const NMSymbol &B) {
    194   if (!ReverseSort) {
    195     if (A.Size < B.Size)
    196       return true;
    197     else if (A.Size == B.Size && A.Name < B.Name)
    198       return true;
    199     else if (A.Size == B.Size && A.Name == B.Name && A.Address < B.Address)
    200       return true;
    201     else
    202       return false;
    203   } else {
    204     if (A.Size > B.Size)
    205       return true;
    206     else if (A.Size == B.Size && A.Name > B.Name)
    207       return true;
    208     else if (A.Size == B.Size && A.Name == B.Name && A.Address > B.Address)
    209       return true;
    210     else
    211       return false;
    212   }
    213 }
    214 
    215 static bool compareSymbolName(const NMSymbol &A, const NMSymbol &B) {
    216   if (!ReverseSort) {
    217     if (A.Name < B.Name)
    218       return true;
    219     else if (A.Name == B.Name && A.Size < B.Size)
    220       return true;
    221     else if (A.Name == B.Name && A.Size == B.Size && A.Address < B.Address)
    222       return true;
    223     else
    224       return false;
    225   } else {
    226     if (A.Name > B.Name)
    227       return true;
    228     else if (A.Name == B.Name && A.Size > B.Size)
    229       return true;
    230     else if (A.Name == B.Name && A.Size == B.Size && A.Address > B.Address)
    231       return true;
    232     else
    233       return false;
    234   }
    235 }
    236 
    237 static char isSymbolList64Bit(SymbolicFile *Obj) {
    238   if (isa<IRObjectFile>(Obj))
    239     return false;
    240   else if (isa<COFFObjectFile>(Obj))
    241     return false;
    242   else if (MachOObjectFile *MachO = dyn_cast<MachOObjectFile>(Obj))
    243     return MachO->is64Bit();
    244   else if (isa<ELF32LEObjectFile>(Obj))
    245     return false;
    246   else if (isa<ELF64LEObjectFile>(Obj))
    247     return true;
    248   else if (isa<ELF32BEObjectFile>(Obj))
    249     return false;
    250   else if (isa<ELF64BEObjectFile>(Obj))
    251     return true;
    252   else
    253     return false;
    254 }
    255 
    256 static StringRef CurrentFilename;
    257 typedef std::vector<NMSymbol> SymbolListT;
    258 static SymbolListT SymbolList;
    259 
    260 // darwinPrintSymbol() is used to print a symbol from a Mach-O file when the
    261 // the OutputFormat is darwin.  It produces the same output as darwin's nm(1) -m
    262 // output.
    263 static void darwinPrintSymbol(MachOObjectFile *MachO, SymbolListT::iterator I,
    264                               char *SymbolAddrStr, const char *printBlanks) {
    265   MachO::mach_header H;
    266   MachO::mach_header_64 H_64;
    267   uint32_t Filetype, Flags;
    268   MachO::nlist_64 STE_64;
    269   MachO::nlist STE;
    270   uint8_t NType;
    271   uint16_t NDesc;
    272   uint64_t NValue;
    273   if (MachO->is64Bit()) {
    274     H_64 = MachO->MachOObjectFile::getHeader64();
    275     Filetype = H_64.filetype;
    276     Flags = H_64.flags;
    277     STE_64 = MachO->getSymbol64TableEntry(I->Symb);
    278     NType = STE_64.n_type;
    279     NDesc = STE_64.n_desc;
    280     NValue = STE_64.n_value;
    281   } else {
    282     H = MachO->MachOObjectFile::getHeader();
    283     Filetype = H.filetype;
    284     Flags = H.flags;
    285     STE = MachO->getSymbolTableEntry(I->Symb);
    286     NType = STE.n_type;
    287     NDesc = STE.n_desc;
    288     NValue = STE.n_value;
    289   }
    290 
    291   if (PrintAddress) {
    292     if ((NType & MachO::N_TYPE) == MachO::N_INDR)
    293       strcpy(SymbolAddrStr, printBlanks);
    294     outs() << SymbolAddrStr << ' ';
    295   }
    296 
    297   switch (NType & MachO::N_TYPE) {
    298   case MachO::N_UNDF:
    299     if (NValue != 0) {
    300       outs() << "(common) ";
    301       if (MachO::GET_COMM_ALIGN(NDesc) != 0)
    302         outs() << "(alignment 2^" << (int)MachO::GET_COMM_ALIGN(NDesc) << ") ";
    303     } else {
    304       if ((NType & MachO::N_TYPE) == MachO::N_PBUD)
    305         outs() << "(prebound ";
    306       else
    307         outs() << "(";
    308       if ((NDesc & MachO::REFERENCE_TYPE) ==
    309           MachO::REFERENCE_FLAG_UNDEFINED_LAZY)
    310         outs() << "undefined [lazy bound]) ";
    311       else if ((NDesc & MachO::REFERENCE_TYPE) ==
    312                MachO::REFERENCE_FLAG_UNDEFINED_LAZY)
    313         outs() << "undefined [private lazy bound]) ";
    314       else if ((NDesc & MachO::REFERENCE_TYPE) ==
    315                MachO::REFERENCE_FLAG_PRIVATE_UNDEFINED_NON_LAZY)
    316         outs() << "undefined [private]) ";
    317       else
    318         outs() << "undefined) ";
    319     }
    320     break;
    321   case MachO::N_ABS:
    322     outs() << "(absolute) ";
    323     break;
    324   case MachO::N_INDR:
    325     outs() << "(indirect) ";
    326     break;
    327   case MachO::N_SECT: {
    328     section_iterator Sec = MachO->section_end();
    329     MachO->getSymbolSection(I->Symb, Sec);
    330     DataRefImpl Ref = Sec->getRawDataRefImpl();
    331     StringRef SectionName;
    332     MachO->getSectionName(Ref, SectionName);
    333     StringRef SegmentName = MachO->getSectionFinalSegmentName(Ref);
    334     outs() << "(" << SegmentName << "," << SectionName << ") ";
    335     break;
    336   }
    337   default:
    338     outs() << "(?) ";
    339     break;
    340   }
    341 
    342   if (NType & MachO::N_EXT) {
    343     if (NDesc & MachO::REFERENCED_DYNAMICALLY)
    344       outs() << "[referenced dynamically] ";
    345     if (NType & MachO::N_PEXT) {
    346       if ((NDesc & MachO::N_WEAK_DEF) == MachO::N_WEAK_DEF)
    347         outs() << "weak private external ";
    348       else
    349         outs() << "private external ";
    350     } else {
    351       if ((NDesc & MachO::N_WEAK_REF) == MachO::N_WEAK_REF ||
    352           (NDesc & MachO::N_WEAK_DEF) == MachO::N_WEAK_DEF) {
    353         if ((NDesc & (MachO::N_WEAK_REF | MachO::N_WEAK_DEF)) ==
    354             (MachO::N_WEAK_REF | MachO::N_WEAK_DEF))
    355           outs() << "weak external automatically hidden ";
    356         else
    357           outs() << "weak external ";
    358       } else
    359         outs() << "external ";
    360     }
    361   } else {
    362     if (NType & MachO::N_PEXT)
    363       outs() << "non-external (was a private external) ";
    364     else
    365       outs() << "non-external ";
    366   }
    367 
    368   if (Filetype == MachO::MH_OBJECT &&
    369       (NDesc & MachO::N_NO_DEAD_STRIP) == MachO::N_NO_DEAD_STRIP)
    370     outs() << "[no dead strip] ";
    371 
    372   if (Filetype == MachO::MH_OBJECT &&
    373       ((NType & MachO::N_TYPE) != MachO::N_UNDF) &&
    374       (NDesc & MachO::N_SYMBOL_RESOLVER) == MachO::N_SYMBOL_RESOLVER)
    375     outs() << "[symbol resolver] ";
    376 
    377   if (Filetype == MachO::MH_OBJECT &&
    378       ((NType & MachO::N_TYPE) != MachO::N_UNDF) &&
    379       (NDesc & MachO::N_ALT_ENTRY) == MachO::N_ALT_ENTRY)
    380     outs() << "[alt entry] ";
    381 
    382   if ((NDesc & MachO::N_ARM_THUMB_DEF) == MachO::N_ARM_THUMB_DEF)
    383     outs() << "[Thumb] ";
    384 
    385   if ((NType & MachO::N_TYPE) == MachO::N_INDR) {
    386     outs() << I->Name << " (for ";
    387     StringRef IndirectName;
    388     if (MachO->getIndirectName(I->Symb, IndirectName))
    389       outs() << "?)";
    390     else
    391       outs() << IndirectName << ")";
    392   } else
    393     outs() << I->Name;
    394 
    395   if ((Flags & MachO::MH_TWOLEVEL) == MachO::MH_TWOLEVEL &&
    396       (((NType & MachO::N_TYPE) == MachO::N_UNDF && NValue == 0) ||
    397        (NType & MachO::N_TYPE) == MachO::N_PBUD)) {
    398     uint32_t LibraryOrdinal = MachO::GET_LIBRARY_ORDINAL(NDesc);
    399     if (LibraryOrdinal != 0) {
    400       if (LibraryOrdinal == MachO::EXECUTABLE_ORDINAL)
    401         outs() << " (from executable)";
    402       else if (LibraryOrdinal == MachO::DYNAMIC_LOOKUP_ORDINAL)
    403         outs() << " (dynamically looked up)";
    404       else {
    405         StringRef LibraryName;
    406         if (MachO->getLibraryShortNameByIndex(LibraryOrdinal - 1, LibraryName))
    407           outs() << " (from bad library ordinal " << LibraryOrdinal << ")";
    408         else
    409           outs() << " (from " << LibraryName << ")";
    410       }
    411     }
    412   }
    413 
    414   outs() << "\n";
    415 }
    416 
    417 static void sortAndPrintSymbolList(SymbolicFile *Obj, bool printName) {
    418   if (!NoSort) {
    419     if (NumericSort)
    420       std::sort(SymbolList.begin(), SymbolList.end(), compareSymbolAddress);
    421     else if (SizeSort)
    422       std::sort(SymbolList.begin(), SymbolList.end(), compareSymbolSize);
    423     else
    424       std::sort(SymbolList.begin(), SymbolList.end(), compareSymbolName);
    425   }
    426 
    427   if (OutputFormat == posix && MultipleFiles && printName) {
    428     outs() << '\n' << CurrentFilename << ":\n";
    429   } else if (OutputFormat == bsd && MultipleFiles && printName) {
    430     outs() << "\n" << CurrentFilename << ":\n";
    431   } else if (OutputFormat == sysv) {
    432     outs() << "\n\nSymbols from " << CurrentFilename << ":\n\n"
    433            << "Name                  Value   Class        Type"
    434            << "         Size   Line  Section\n";
    435   }
    436 
    437   const char *printBlanks, *printFormat;
    438   if (isSymbolList64Bit(Obj)) {
    439     printBlanks = "                ";
    440     printFormat = "%016" PRIx64;
    441   } else {
    442     printBlanks = "        ";
    443     printFormat = "%08" PRIx64;
    444   }
    445 
    446   for (SymbolListT::iterator I = SymbolList.begin(), E = SymbolList.end();
    447        I != E; ++I) {
    448     if ((I->TypeChar != 'U') && UndefinedOnly)
    449       continue;
    450     if ((I->TypeChar == 'U') && DefinedOnly)
    451       continue;
    452     if (SizeSort && !PrintAddress && I->Size == UnknownAddressOrSize)
    453       continue;
    454     if (JustSymbolName) {
    455       outs() << I->Name << "\n";
    456       continue;
    457     }
    458 
    459     char SymbolAddrStr[18] = "";
    460     char SymbolSizeStr[18] = "";
    461 
    462     if (OutputFormat == sysv || I->Address == UnknownAddressOrSize)
    463       strcpy(SymbolAddrStr, printBlanks);
    464     if (OutputFormat == sysv)
    465       strcpy(SymbolSizeStr, printBlanks);
    466 
    467     if (I->Address != UnknownAddressOrSize)
    468       format(printFormat, I->Address)
    469           .print(SymbolAddrStr, sizeof(SymbolAddrStr));
    470     if (I->Size != UnknownAddressOrSize)
    471       format(printFormat, I->Size).print(SymbolSizeStr, sizeof(SymbolSizeStr));
    472 
    473     // If OutputFormat is darwin and we have a MachOObjectFile print as darwin's
    474     // nm(1) -m output, else if OutputFormat is darwin and not a Mach-O object
    475     // fall back to OutputFormat bsd (see below).
    476     MachOObjectFile *MachO = dyn_cast<MachOObjectFile>(Obj);
    477     if (OutputFormat == darwin && MachO) {
    478       darwinPrintSymbol(MachO, I, SymbolAddrStr, printBlanks);
    479     } else if (OutputFormat == posix) {
    480       outs() << I->Name << " " << I->TypeChar << " " << SymbolAddrStr
    481              << SymbolSizeStr << "\n";
    482     } else if (OutputFormat == bsd || (OutputFormat == darwin && !MachO)) {
    483       if (PrintAddress)
    484         outs() << SymbolAddrStr << ' ';
    485       if (PrintSize) {
    486         outs() << SymbolSizeStr;
    487         if (I->Size != UnknownAddressOrSize)
    488           outs() << ' ';
    489       }
    490       outs() << I->TypeChar << " " << I->Name << "\n";
    491     } else if (OutputFormat == sysv) {
    492       std::string PaddedName(I->Name);
    493       while (PaddedName.length() < 20)
    494         PaddedName += " ";
    495       outs() << PaddedName << "|" << SymbolAddrStr << "|   " << I->TypeChar
    496              << "  |                  |" << SymbolSizeStr << "|     |\n";
    497     }
    498   }
    499 
    500   SymbolList.clear();
    501 }
    502 
    503 template <class ELFT>
    504 static char getSymbolNMTypeChar(ELFObjectFile<ELFT> &Obj,
    505                                 basic_symbol_iterator I) {
    506   typedef typename ELFObjectFile<ELFT>::Elf_Sym Elf_Sym;
    507   typedef typename ELFObjectFile<ELFT>::Elf_Shdr Elf_Shdr;
    508 
    509   // OK, this is ELF
    510   symbol_iterator SymI(I);
    511 
    512   DataRefImpl Symb = I->getRawDataRefImpl();
    513   const Elf_Sym *ESym = Obj.getSymbol(Symb);
    514   const ELFFile<ELFT> &EF = *Obj.getELFFile();
    515   const Elf_Shdr *ESec = EF.getSection(ESym);
    516 
    517   if (ESec) {
    518     switch (ESec->sh_type) {
    519     case ELF::SHT_PROGBITS:
    520     case ELF::SHT_DYNAMIC:
    521       switch (ESec->sh_flags) {
    522       case (ELF::SHF_ALLOC | ELF::SHF_EXECINSTR):
    523         return 't';
    524       case (ELF::SHF_TLS | ELF::SHF_ALLOC | ELF::SHF_WRITE):
    525       case (ELF::SHF_ALLOC | ELF::SHF_WRITE):
    526         return 'd';
    527       case ELF::SHF_ALLOC:
    528       case (ELF::SHF_ALLOC | ELF::SHF_MERGE):
    529       case (ELF::SHF_ALLOC | ELF::SHF_MERGE | ELF::SHF_STRINGS):
    530         return 'r';
    531       }
    532       break;
    533     case ELF::SHT_NOBITS:
    534       return 'b';
    535     }
    536   }
    537 
    538   if (ESym->getType() == ELF::STT_SECTION) {
    539     StringRef Name;
    540     if (error(SymI->getName(Name)))
    541       return '?';
    542     return StringSwitch<char>(Name)
    543         .StartsWith(".debug", 'N')
    544         .StartsWith(".note", 'n')
    545         .Default('?');
    546   }
    547 
    548   return '?';
    549 }
    550 
    551 static char getSymbolNMTypeChar(COFFObjectFile &Obj, symbol_iterator I) {
    552   const coff_symbol *Symb = Obj.getCOFFSymbol(*I);
    553   // OK, this is COFF.
    554   symbol_iterator SymI(I);
    555 
    556   StringRef Name;
    557   if (error(SymI->getName(Name)))
    558     return '?';
    559 
    560   char Ret = StringSwitch<char>(Name)
    561                  .StartsWith(".debug", 'N')
    562                  .StartsWith(".sxdata", 'N')
    563                  .Default('?');
    564 
    565   if (Ret != '?')
    566     return Ret;
    567 
    568   uint32_t Characteristics = 0;
    569   if (!COFF::isReservedSectionNumber(Symb->SectionNumber)) {
    570     section_iterator SecI = Obj.section_end();
    571     if (error(SymI->getSection(SecI)))
    572       return '?';
    573     const coff_section *Section = Obj.getCOFFSection(*SecI);
    574     Characteristics = Section->Characteristics;
    575   }
    576 
    577   switch (Symb->SectionNumber) {
    578   case COFF::IMAGE_SYM_DEBUG:
    579     return 'n';
    580   default:
    581     // Check section type.
    582     if (Characteristics & COFF::IMAGE_SCN_CNT_CODE)
    583       return 't';
    584     else if (Characteristics & COFF::IMAGE_SCN_MEM_READ &&
    585              ~Characteristics & COFF::IMAGE_SCN_MEM_WRITE) // Read only.
    586       return 'r';
    587     else if (Characteristics & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA)
    588       return 'd';
    589     else if (Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA)
    590       return 'b';
    591     else if (Characteristics & COFF::IMAGE_SCN_LNK_INFO)
    592       return 'i';
    593 
    594     // Check for section symbol.
    595     else if (Symb->isSectionDefinition())
    596       return 's';
    597   }
    598 
    599   return '?';
    600 }
    601 
    602 static uint8_t getNType(MachOObjectFile &Obj, DataRefImpl Symb) {
    603   if (Obj.is64Bit()) {
    604     MachO::nlist_64 STE = Obj.getSymbol64TableEntry(Symb);
    605     return STE.n_type;
    606   }
    607   MachO::nlist STE = Obj.getSymbolTableEntry(Symb);
    608   return STE.n_type;
    609 }
    610 
    611 static char getSymbolNMTypeChar(MachOObjectFile &Obj, basic_symbol_iterator I) {
    612   DataRefImpl Symb = I->getRawDataRefImpl();
    613   uint8_t NType = getNType(Obj, Symb);
    614 
    615   switch (NType & MachO::N_TYPE) {
    616   case MachO::N_ABS:
    617     return 's';
    618   case MachO::N_INDR:
    619     return 'i';
    620   case MachO::N_SECT: {
    621     section_iterator Sec = Obj.section_end();
    622     Obj.getSymbolSection(Symb, Sec);
    623     DataRefImpl Ref = Sec->getRawDataRefImpl();
    624     StringRef SectionName;
    625     Obj.getSectionName(Ref, SectionName);
    626     StringRef SegmentName = Obj.getSectionFinalSegmentName(Ref);
    627     if (SegmentName == "__TEXT" && SectionName == "__text")
    628       return 't';
    629     else if (SegmentName == "__DATA" && SectionName == "__data")
    630       return 'd';
    631     else if (SegmentName == "__DATA" && SectionName == "__bss")
    632       return 'b';
    633     else
    634       return 's';
    635   }
    636   }
    637 
    638   return '?';
    639 }
    640 
    641 static char getSymbolNMTypeChar(const GlobalValue &GV) {
    642   if (GV.getType()->getElementType()->isFunctionTy())
    643     return 't';
    644   // FIXME: should we print 'b'? At the IR level we cannot be sure if this
    645   // will be in bss or not, but we could approximate.
    646   return 'd';
    647 }
    648 
    649 static char getSymbolNMTypeChar(IRObjectFile &Obj, basic_symbol_iterator I) {
    650   const GlobalValue *GV = Obj.getSymbolGV(I->getRawDataRefImpl());
    651   if (!GV)
    652     return 't';
    653   return getSymbolNMTypeChar(*GV);
    654 }
    655 
    656 template <class ELFT>
    657 static bool isObject(ELFObjectFile<ELFT> &Obj, symbol_iterator I) {
    658   typedef typename ELFObjectFile<ELFT>::Elf_Sym Elf_Sym;
    659 
    660   DataRefImpl Symb = I->getRawDataRefImpl();
    661   const Elf_Sym *ESym = Obj.getSymbol(Symb);
    662 
    663   return ESym->getType() == ELF::STT_OBJECT;
    664 }
    665 
    666 static bool isObject(SymbolicFile *Obj, basic_symbol_iterator I) {
    667   if (ELF32LEObjectFile *ELF = dyn_cast<ELF32LEObjectFile>(Obj))
    668     return isObject(*ELF, I);
    669   if (ELF64LEObjectFile *ELF = dyn_cast<ELF64LEObjectFile>(Obj))
    670     return isObject(*ELF, I);
    671   if (ELF32BEObjectFile *ELF = dyn_cast<ELF32BEObjectFile>(Obj))
    672     return isObject(*ELF, I);
    673   if (ELF64BEObjectFile *ELF = dyn_cast<ELF64BEObjectFile>(Obj))
    674     return isObject(*ELF, I);
    675   return false;
    676 }
    677 
    678 static char getNMTypeChar(SymbolicFile *Obj, basic_symbol_iterator I) {
    679   uint32_t Symflags = I->getFlags();
    680   if ((Symflags & object::SymbolRef::SF_Weak) && !isa<MachOObjectFile>(Obj)) {
    681     char Ret = isObject(Obj, I) ? 'v' : 'w';
    682     if (!(Symflags & object::SymbolRef::SF_Undefined))
    683       Ret = toupper(Ret);
    684     return Ret;
    685   }
    686 
    687   if (Symflags & object::SymbolRef::SF_Undefined)
    688     return 'U';
    689 
    690   if (Symflags & object::SymbolRef::SF_Common)
    691     return 'C';
    692 
    693   char Ret = '?';
    694   if (Symflags & object::SymbolRef::SF_Absolute)
    695     Ret = 'a';
    696   else if (IRObjectFile *IR = dyn_cast<IRObjectFile>(Obj))
    697     Ret = getSymbolNMTypeChar(*IR, I);
    698   else if (COFFObjectFile *COFF = dyn_cast<COFFObjectFile>(Obj))
    699     Ret = getSymbolNMTypeChar(*COFF, I);
    700   else if (MachOObjectFile *MachO = dyn_cast<MachOObjectFile>(Obj))
    701     Ret = getSymbolNMTypeChar(*MachO, I);
    702   else if (ELF32LEObjectFile *ELF = dyn_cast<ELF32LEObjectFile>(Obj))
    703     Ret = getSymbolNMTypeChar(*ELF, I);
    704   else if (ELF64LEObjectFile *ELF = dyn_cast<ELF64LEObjectFile>(Obj))
    705     Ret = getSymbolNMTypeChar(*ELF, I);
    706   else if (ELF32BEObjectFile *ELF = dyn_cast<ELF32BEObjectFile>(Obj))
    707     Ret = getSymbolNMTypeChar(*ELF, I);
    708   else
    709     Ret = getSymbolNMTypeChar(*cast<ELF64BEObjectFile>(Obj), I);
    710 
    711   if (Symflags & object::SymbolRef::SF_Global)
    712     Ret = toupper(Ret);
    713 
    714   return Ret;
    715 }
    716 
    717 static void dumpSymbolNamesFromObject(SymbolicFile *Obj, bool printName) {
    718   basic_symbol_iterator IBegin = Obj->symbol_begin();
    719   basic_symbol_iterator IEnd = Obj->symbol_end();
    720   if (DynamicSyms) {
    721     if (!Obj->isELF()) {
    722       error("File format has no dynamic symbol table", Obj->getFileName());
    723       return;
    724     }
    725     std::pair<symbol_iterator, symbol_iterator> IDyn =
    726         getELFDynamicSymbolIterators(Obj);
    727     IBegin = IDyn.first;
    728     IEnd = IDyn.second;
    729   }
    730   std::string NameBuffer;
    731   raw_string_ostream OS(NameBuffer);
    732   for (basic_symbol_iterator I = IBegin; I != IEnd; ++I) {
    733     uint32_t SymFlags = I->getFlags();
    734     if (!DebugSyms && (SymFlags & SymbolRef::SF_FormatSpecific))
    735       continue;
    736     if (WithoutAliases) {
    737       if (IRObjectFile *IR = dyn_cast<IRObjectFile>(Obj)) {
    738         const GlobalValue *GV = IR->getSymbolGV(I->getRawDataRefImpl());
    739         if (GV && isa<GlobalAlias>(GV))
    740           continue;
    741       }
    742     }
    743     NMSymbol S;
    744     S.Size = UnknownAddressOrSize;
    745     S.Address = UnknownAddressOrSize;
    746     if ((PrintSize || SizeSort) && isa<ObjectFile>(Obj)) {
    747       symbol_iterator SymI = I;
    748       if (error(SymI->getSize(S.Size)))
    749         break;
    750     }
    751     if (PrintAddress && isa<ObjectFile>(Obj))
    752       if (error(symbol_iterator(I)->getAddress(S.Address)))
    753         break;
    754     S.TypeChar = getNMTypeChar(Obj, I);
    755     if (error(I->printName(OS)))
    756       break;
    757     OS << '\0';
    758     S.Symb = I->getRawDataRefImpl();
    759     SymbolList.push_back(S);
    760   }
    761 
    762   OS.flush();
    763   const char *P = NameBuffer.c_str();
    764   for (unsigned I = 0; I < SymbolList.size(); ++I) {
    765     SymbolList[I].Name = P;
    766     P += strlen(P) + 1;
    767   }
    768 
    769   CurrentFilename = Obj->getFileName();
    770   sortAndPrintSymbolList(Obj, printName);
    771 }
    772 
    773 // checkMachOAndArchFlags() checks to see if the SymbolicFile is a Mach-O file
    774 // and if it is and there is a list of architecture flags is specified then
    775 // check to make sure this Mach-O file is one of those architectures or all
    776 // architectures was specificed.  If not then an error is generated and this
    777 // routine returns false.  Else it returns true.
    778 static bool checkMachOAndArchFlags(SymbolicFile *O, std::string &Filename) {
    779   if (isa<MachOObjectFile>(O) && !ArchAll && ArchFlags.size() != 0) {
    780     MachOObjectFile *MachO = dyn_cast<MachOObjectFile>(O);
    781     bool ArchFound = false;
    782     MachO::mach_header H;
    783     MachO::mach_header_64 H_64;
    784     Triple T;
    785     if (MachO->is64Bit()) {
    786       H_64 = MachO->MachOObjectFile::getHeader64();
    787       T = MachOObjectFile::getArch(H_64.cputype, H_64.cpusubtype);
    788     } else {
    789       H = MachO->MachOObjectFile::getHeader();
    790       T = MachOObjectFile::getArch(H.cputype, H.cpusubtype);
    791     }
    792     unsigned i;
    793     for (i = 0; i < ArchFlags.size(); ++i) {
    794       if (ArchFlags[i] == T.getArchName())
    795         ArchFound = true;
    796       break;
    797     }
    798     if (!ArchFound) {
    799       error(ArchFlags[i],
    800             "file: " + Filename + " does not contain architecture");
    801       return false;
    802     }
    803   }
    804   return true;
    805 }
    806 
    807 static void dumpSymbolNamesFromFile(std::string &Filename) {
    808   ErrorOr<std::unique_ptr<MemoryBuffer>> BufferOrErr =
    809       MemoryBuffer::getFileOrSTDIN(Filename);
    810   if (error(BufferOrErr.getError(), Filename))
    811     return;
    812   std::unique_ptr<MemoryBuffer> Buffer = std::move(BufferOrErr.get());
    813 
    814   LLVMContext &Context = getGlobalContext();
    815   ErrorOr<Binary *> BinaryOrErr = createBinary(Buffer, &Context);
    816   if (error(BinaryOrErr.getError(), Filename))
    817     return;
    818   Buffer.release();
    819   std::unique_ptr<Binary> Bin(BinaryOrErr.get());
    820 
    821   if (Archive *A = dyn_cast<Archive>(Bin.get())) {
    822     if (ArchiveMap) {
    823       Archive::symbol_iterator I = A->symbol_begin();
    824       Archive::symbol_iterator E = A->symbol_end();
    825       if (I != E) {
    826         outs() << "Archive map\n";
    827         for (; I != E; ++I) {
    828           ErrorOr<Archive::child_iterator> C = I->getMember();
    829           if (error(C.getError()))
    830             return;
    831           ErrorOr<StringRef> FileNameOrErr = C.get()->getName();
    832           if (error(FileNameOrErr.getError()))
    833             return;
    834           StringRef SymName = I->getName();
    835           outs() << SymName << " in " << FileNameOrErr.get() << "\n";
    836         }
    837         outs() << "\n";
    838       }
    839     }
    840 
    841     for (Archive::child_iterator I = A->child_begin(), E = A->child_end();
    842          I != E; ++I) {
    843       ErrorOr<std::unique_ptr<Binary>> ChildOrErr = I->getAsBinary(&Context);
    844       if (ChildOrErr.getError())
    845         continue;
    846       if (SymbolicFile *O = dyn_cast<SymbolicFile>(&*ChildOrErr.get())) {
    847         if (!checkMachOAndArchFlags(O, Filename))
    848           return;
    849         outs() << "\n";
    850         if (isa<MachOObjectFile>(O)) {
    851           outs() << Filename << "(" << O->getFileName() << ")";
    852         } else
    853           outs() << O->getFileName();
    854         outs() << ":\n";
    855         dumpSymbolNamesFromObject(O, false);
    856       }
    857     }
    858     return;
    859   }
    860   if (MachOUniversalBinary *UB = dyn_cast<MachOUniversalBinary>(Bin.get())) {
    861     // If we have a list of architecture flags specified dump only those.
    862     if (!ArchAll && ArchFlags.size() != 0) {
    863       // Look for a slice in the universal binary that matches each ArchFlag.
    864       bool ArchFound;
    865       for (unsigned i = 0; i < ArchFlags.size(); ++i) {
    866         ArchFound = false;
    867         for (MachOUniversalBinary::object_iterator I = UB->begin_objects(),
    868                                                    E = UB->end_objects();
    869              I != E; ++I) {
    870           if (ArchFlags[i] == I->getArchTypeName()) {
    871             ArchFound = true;
    872             ErrorOr<std::unique_ptr<ObjectFile>> ObjOrErr =
    873                 I->getAsObjectFile();
    874             std::unique_ptr<Archive> A;
    875             if (ObjOrErr) {
    876               std::unique_ptr<ObjectFile> Obj = std::move(ObjOrErr.get());
    877               if (ArchFlags.size() > 1) {
    878                 outs() << "\n" << Obj->getFileName() << " (for architecture "
    879                        << I->getArchTypeName() << ")"
    880                        << ":\n";
    881               }
    882               dumpSymbolNamesFromObject(Obj.get(), false);
    883             } else if (!I->getAsArchive(A)) {
    884               for (Archive::child_iterator AI = A->child_begin(),
    885                                            AE = A->child_end();
    886                    AI != AE; ++AI) {
    887                 ErrorOr<std::unique_ptr<Binary>> ChildOrErr =
    888                     AI->getAsBinary(&Context);
    889                 if (ChildOrErr.getError())
    890                   continue;
    891                 if (SymbolicFile *O =
    892                         dyn_cast<SymbolicFile>(&*ChildOrErr.get())) {
    893                   outs() << "\n" << A->getFileName();
    894                   outs() << "(" << O->getFileName() << ")";
    895                   if (ArchFlags.size() > 1) {
    896                     outs() << " (for architecture " << I->getArchTypeName()
    897                            << ")";
    898                   }
    899                   outs() << ":\n";
    900                   dumpSymbolNamesFromObject(O, false);
    901                 }
    902               }
    903             }
    904           }
    905         }
    906         if (!ArchFound) {
    907           error(ArchFlags[i],
    908                 "file: " + Filename + " does not contain architecture");
    909           return;
    910         }
    911       }
    912       return;
    913     }
    914     // No architecture flags were specified so if this contains a slice that
    915     // matches the host architecture dump only that.
    916     if (!ArchAll) {
    917       StringRef HostArchName = MachOObjectFile::getHostArch().getArchName();
    918       for (MachOUniversalBinary::object_iterator I = UB->begin_objects(),
    919                                                  E = UB->end_objects();
    920            I != E; ++I) {
    921         if (HostArchName == I->getArchTypeName()) {
    922           ErrorOr<std::unique_ptr<ObjectFile>> ObjOrErr = I->getAsObjectFile();
    923           std::unique_ptr<Archive> A;
    924           if (ObjOrErr) {
    925             std::unique_ptr<ObjectFile> Obj = std::move(ObjOrErr.get());
    926             dumpSymbolNamesFromObject(Obj.get(), false);
    927           } else if (!I->getAsArchive(A)) {
    928             for (Archive::child_iterator AI = A->child_begin(),
    929                                          AE = A->child_end();
    930                  AI != AE; ++AI) {
    931               ErrorOr<std::unique_ptr<Binary>> ChildOrErr =
    932                   AI->getAsBinary(&Context);
    933               if (ChildOrErr.getError())
    934                 continue;
    935               if (SymbolicFile *O =
    936                       dyn_cast<SymbolicFile>(&*ChildOrErr.get())) {
    937                 outs() << "\n" << A->getFileName() << "(" << O->getFileName()
    938                        << ")"
    939                        << ":\n";
    940                 dumpSymbolNamesFromObject(O, false);
    941               }
    942             }
    943           }
    944           return;
    945         }
    946       }
    947     }
    948     // Either all architectures have been specified or none have been specified
    949     // and this does not contain the host architecture so dump all the slices.
    950     bool moreThanOneArch = UB->getNumberOfObjects() > 1;
    951     for (MachOUniversalBinary::object_iterator I = UB->begin_objects(),
    952                                                E = UB->end_objects();
    953          I != E; ++I) {
    954       ErrorOr<std::unique_ptr<ObjectFile>> ObjOrErr = I->getAsObjectFile();
    955       std::unique_ptr<Archive> A;
    956       if (ObjOrErr) {
    957         std::unique_ptr<ObjectFile> Obj = std::move(ObjOrErr.get());
    958         if (moreThanOneArch)
    959           outs() << "\n";
    960         outs() << Obj->getFileName();
    961         if (isa<MachOObjectFile>(Obj.get()) && moreThanOneArch)
    962           outs() << " (for architecture " << I->getArchTypeName() << ")";
    963         outs() << ":\n";
    964         dumpSymbolNamesFromObject(Obj.get(), false);
    965       } else if (!I->getAsArchive(A)) {
    966         for (Archive::child_iterator AI = A->child_begin(), AE = A->child_end();
    967              AI != AE; ++AI) {
    968           ErrorOr<std::unique_ptr<Binary>> ChildOrErr =
    969               AI->getAsBinary(&Context);
    970           if (ChildOrErr.getError())
    971             continue;
    972           if (SymbolicFile *O = dyn_cast<SymbolicFile>(&*ChildOrErr.get())) {
    973             outs() << "\n" << A->getFileName();
    974             if (isa<MachOObjectFile>(O)) {
    975               outs() << "(" << O->getFileName() << ")";
    976               if (moreThanOneArch)
    977                 outs() << " (for architecture " << I->getArchTypeName() << ")";
    978             } else
    979               outs() << ":" << O->getFileName();
    980             outs() << ":\n";
    981             dumpSymbolNamesFromObject(O, false);
    982           }
    983         }
    984       }
    985     }
    986     return;
    987   }
    988   if (SymbolicFile *O = dyn_cast<SymbolicFile>(Bin.get())) {
    989     if (!checkMachOAndArchFlags(O, Filename))
    990       return;
    991     dumpSymbolNamesFromObject(O, true);
    992     return;
    993   }
    994   error("unrecognizable file type", Filename);
    995   return;
    996 }
    997 
    998 int main(int argc, char **argv) {
    999   // Print a stack trace if we signal out.
   1000   sys::PrintStackTraceOnErrorSignal();
   1001   PrettyStackTraceProgram X(argc, argv);
   1002 
   1003   llvm_shutdown_obj Y; // Call llvm_shutdown() on exit.
   1004   cl::ParseCommandLineOptions(argc, argv, "llvm symbol table dumper\n");
   1005 
   1006   // llvm-nm only reads binary files.
   1007   if (error(sys::ChangeStdinToBinary()))
   1008     return 1;
   1009 
   1010   llvm::InitializeAllTargetInfos();
   1011   llvm::InitializeAllTargetMCs();
   1012   llvm::InitializeAllAsmParsers();
   1013 
   1014   ToolName = argv[0];
   1015   if (BSDFormat)
   1016     OutputFormat = bsd;
   1017   if (POSIXFormat)
   1018     OutputFormat = posix;
   1019   if (DarwinFormat)
   1020     OutputFormat = darwin;
   1021 
   1022   // The relative order of these is important. If you pass --size-sort it should
   1023   // only print out the size. However, if you pass -S --size-sort, it should
   1024   // print out both the size and address.
   1025   if (SizeSort && !PrintSize)
   1026     PrintAddress = false;
   1027   if (OutputFormat == sysv || SizeSort)
   1028     PrintSize = true;
   1029 
   1030   switch (InputFilenames.size()) {
   1031   case 0:
   1032     InputFilenames.push_back("a.out");
   1033   case 1:
   1034     break;
   1035   default:
   1036     MultipleFiles = true;
   1037   }
   1038 
   1039   for (unsigned i = 0; i < ArchFlags.size(); ++i) {
   1040     if (ArchFlags[i] == "all") {
   1041       ArchAll = true;
   1042     } else {
   1043       Triple T = MachOObjectFile::getArch(ArchFlags[i]);
   1044       if (T.getArch() == Triple::UnknownArch)
   1045         error("Unknown architecture named '" + ArchFlags[i] + "'",
   1046               "for the -arch option");
   1047     }
   1048   }
   1049 
   1050   std::for_each(InputFilenames.begin(), InputFilenames.end(),
   1051                 dumpSymbolNamesFromFile);
   1052 
   1053   if (HadError)
   1054     return 1;
   1055 
   1056   return 0;
   1057 }
   1058