tools/llvm-dwarfdump/llvm-dwarfdump.cpp

   1 //===-- llvm-dwarfdump.cpp - Debug info 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 "dwarfdump".
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "llvm/ADT/OwningPtr.h"
  15 #include "llvm/ADT/Triple.h"
  16 #include "llvm/ADT/STLExtras.h"
  17 #include "llvm/Object/ObjectFile.h"
  18 #include "llvm/Object/RelocVisitor.h"
  19 #include "llvm/DebugInfo/DIContext.h"
  20 #include "llvm/Support/CommandLine.h"
  21 #include "llvm/Support/Debug.h"
  22 #include "llvm/Support/Format.h"
  23 #include "llvm/Support/ManagedStatic.h"
  24 #include "llvm/Support/MemoryBuffer.h"
  25 #include "llvm/Support/MemoryObject.h"
  26 #include "llvm/Support/PrettyStackTrace.h"
  27 #include "llvm/Support/Signals.h"
  28 #include "llvm/Support/raw_ostream.h"
  29 #include "llvm/Support/system_error.h"
  30 #include <algorithm>
  31 #include <cstring>
  32 #include <list>
  33 #include <string>
  34
  35 using namespace llvm;
  36 using namespace object;
  37
  38 static cl::list<std::string>
  39 InputFilenames(cl::Positional, cl::desc("<input object files>"),
  40                cl::ZeroOrMore);
  41
  42 static cl::opt<unsigned long long>
  43 Address("address", cl::init(-1ULL),
  44         cl::desc("Print line information for a given address"));
  45
  46 static cl::opt<bool>
  47 PrintFunctions("functions", cl::init(false),
  48                cl::desc("Print function names as well as line information "
  49                         "for a given address"));
  50
  51 static cl::opt<bool>
  52 PrintInlining("inlining", cl::init(false),
  53               cl::desc("Print all inlined frames for a given address"));
  54
  55 static void PrintDILineInfo(DILineInfo dli) {
  56   if (PrintFunctions)
  57     outs() << (dli.getFunctionName() ? dli.getFunctionName() : "<unknown>")
  58            << "\n";
  59   outs() << (dli.getFileName() ? dli.getFileName() : "<unknown>") << ':'
  60          << dli.getLine() << ':' << dli.getColumn() << '\n';
  61 }
  62
  63 static void DumpInput(const StringRef &Filename) {
  64   OwningPtr<MemoryBuffer> Buff;
  65
  66   if (error_code ec = MemoryBuffer::getFileOrSTDIN(Filename, Buff)) {
  67     errs() << Filename << ": " << ec.message() << "\n";
  68     return;
  69   }
  70
  71   OwningPtr<ObjectFile> Obj(ObjectFile::createObjectFile(Buff.take()));
  72
  73   StringRef DebugInfoSection;
  74   RelocAddrMap RelocMap;
  75   StringRef DebugAbbrevSection;
  76   StringRef DebugLineSection;
  77   StringRef DebugArangesSection;
  78   StringRef DebugStringSection;
  79   StringRef DebugRangesSection;
  80
  81   error_code ec;
  82   for (section_iterator i = Obj->begin_sections(),
  83                         e = Obj->end_sections();
  84                         i != e; i.increment(ec)) {
  85     StringRef name;
  86     i->getName(name);
  87     StringRef data;
  88     i->getContents(data);
  89
  90     if (name.startswith("__DWARF,"))
  91       name = name.substr(8); // Skip "__DWARF," prefix.
  92     name = name.substr(name.find_first_not_of("._")); // Skip . and _ prefixes.
  93     if (name == "debug_info")
  94       DebugInfoSection = data;
  95     else if (name == "debug_abbrev")
  96       DebugAbbrevSection = data;
  97     else if (name == "debug_line")
  98       DebugLineSection = data;
  99     else if (name == "debug_aranges")
 100       DebugArangesSection = data;
 101     else if (name == "debug_str")
 102       DebugStringSection = data;
 103     else if (name == "debug_ranges")
 104       DebugRangesSection = data;
 105     // Any more debug info sections go here.
 106     else
 107       continue;
 108
 109     // TODO: For now only handle relocations for the debug_info section.
 110     if (name != "debug_info")
 111       continue;
 112
 113     if (i->begin_relocations() != i->end_relocations()) {
 114       uint64_t SectionSize;
 115       i->getSize(SectionSize);
 116       for (relocation_iterator reloc_i = i->begin_relocations(),
 117                                reloc_e = i->end_relocations();
 118                                reloc_i != reloc_e; reloc_i.increment(ec)) {
 119         uint64_t Address;
 120         reloc_i->getAddress(Address);
 121         uint64_t Type;
 122         reloc_i->getType(Type);
 123
 124         RelocVisitor V(Obj->getFileFormatName());
 125         // The section address is always 0 for debug sections.
 126         RelocToApply R(V.visit(Type, *reloc_i));
 127         if (V.error()) {
 128           SmallString<32> Name;
 129           error_code ec(reloc_i->getTypeName(Name));
 130           if (ec) {
 131             errs() << "Aaaaaa! Nameless relocation! Aaaaaa!\n";
 132           }
 133           errs() << "error: failed to compute relocation: "
 134                  << Name << "\n";
 135           continue;
 136         }
 137
 138         if (Address + R.Width > SectionSize) {
 139           errs() << "error: " << R.Width << "-byte relocation starting "
 140                  << Address << " bytes into section " << name << " which is "
 141                  << SectionSize << " bytes long.\n";
 142           continue;
 143         }
 144         if (R.Width > 8) {
 145           errs() << "error: can't handle a relocation of more than 8 bytes at "
 146                     "a time.\n";
 147           continue;
 148         }
 149         DEBUG(dbgs() << "Writing " << format("%p", R.Value)
 150                      << " at " << format("%p", Address)
 151                      << " with width " << format("%d", R.Width)
 152                      << "\n");
 153         RelocMap[Address] = std::make_pair(R.Width, R.Value);
 154       }
 155     }
 156   }
 157
 158   OwningPtr<DIContext> dictx(DIContext::getDWARFContext(/*FIXME*/true,
 159                                                         DebugInfoSection,
 160                                                         DebugAbbrevSection,
 161                                                         DebugArangesSection,
 162                                                         DebugLineSection,
 163                                                         DebugStringSection,
 164                                                         DebugRangesSection,
 165                                                         RelocMap));
 166   if (Address == -1ULL) {
 167     outs() << Filename
 168            << ":\tfile format " << Obj->getFileFormatName() << "\n\n";
 169     // Dump the complete DWARF structure.
 170     dictx->dump(outs());
 171   } else {
 172     // Print line info for the specified address.
 173     int SpecFlags = DILineInfoSpecifier::FileLineInfo |
 174                     DILineInfoSpecifier::AbsoluteFilePath;
 175     if (PrintFunctions)
 176       SpecFlags |= DILineInfoSpecifier::FunctionName;
 177     if (PrintInlining) {
 178       DIInliningInfo InliningInfo =
 179         dictx->getInliningInfoForAddress(Address, SpecFlags);
 180       uint32_t n = InliningInfo.getNumberOfFrames();
 181       if (n == 0) {
 182         // Print one empty debug line info in any case.
 183         PrintDILineInfo(DILineInfo());
 184       } else {
 185         for (uint32_t i = 0; i < n; i++) {
 186           DILineInfo dli = InliningInfo.getFrame(i);
 187           PrintDILineInfo(dli);
 188         }
 189       }
 190     } else {
 191       DILineInfo dli = dictx->getLineInfoForAddress(Address, SpecFlags);
 192       PrintDILineInfo(dli);
 193     }
 194   }
 195 }
 196
 197 int main(int argc, char **argv) {
 198   // Print a stack trace if we signal out.
 199   sys::PrintStackTraceOnErrorSignal();
 200   PrettyStackTraceProgram X(argc, argv);
 201   llvm_shutdown_obj Y;  // Call llvm_shutdown() on exit.
 202
 203   cl::ParseCommandLineOptions(argc, argv, "llvm dwarf dumper\n");
 204
 205   // Defaults to a.out if no filenames specified.
 206   if (InputFilenames.size() == 0)
 207     InputFilenames.push_back("a.out");
 208
 209   std::for_each(InputFilenames.begin(), InputFilenames.end(), DumpInput);
 210
 211   return 0;
 212 }