1 //===- MapFile.cpp --------------------------------------------------------===// 2 // 3 // The LLVM Linker 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 -Map option. It shows lists in order and 11 // hierarchically the output sections, input sections, input files and 12 // symbol: 13 // 14 // Address Size Align Out In Symbol 15 // 00201000 00000015 4 .text 16 // 00201000 0000000e 4 test.o:(.text) 17 // 0020100e 00000000 0 local 18 // 00201005 00000000 0 f(int) 19 // 20 //===----------------------------------------------------------------------===// 21 22 #include "MapFile.h" 23 #include "InputFiles.h" 24 #include "Strings.h" 25 #include "SymbolTable.h" 26 #include "Threads.h" 27 28 #include "llvm/Support/raw_ostream.h" 29 30 using namespace llvm; 31 using namespace llvm::object; 32 33 using namespace lld; 34 using namespace lld::elf; 35 36 typedef DenseMap<const SectionBase *, SmallVector<DefinedRegular *, 4>> 37 SymbolMapTy; 38 39 // Print out the first three columns of a line. 40 template <class ELFT> 41 static void writeHeader(raw_ostream &OS, uint64_t Addr, uint64_t Size, 42 uint64_t Align) { 43 int W = ELFT::Is64Bits ? 16 : 8; 44 OS << format("%0*llx %0*llx %5lld ", W, Addr, W, Size, Align); 45 } 46 47 static std::string indent(int Depth) { return std::string(Depth * 8, ' '); } 48 49 // Returns a list of all symbols that we want to print out. 50 template <class ELFT> std::vector<DefinedRegular *> getSymbols() { 51 std::vector<DefinedRegular *> V; 52 for (elf::ObjectFile<ELFT> *File : Symtab<ELFT>::X->getObjectFiles()) 53 for (SymbolBody *B : File->getSymbols()) 54 if (B->File == File && !B->isSection()) 55 if (auto *Sym = dyn_cast<DefinedRegular>(B)) 56 if (Sym->Section) 57 V.push_back(Sym); 58 return V; 59 } 60 61 // Returns a map from sections to their symbols. 62 template <class ELFT> 63 SymbolMapTy getSectionSyms(ArrayRef<DefinedRegular *> Syms) { 64 SymbolMapTy Ret; 65 for (DefinedRegular *S : Syms) 66 Ret[S->Section].push_back(S); 67 68 // Sort symbols by address. We want to print out symbols in the 69 // order in the output file rather than the order they appeared 70 // in the input files. 71 for (auto &It : Ret) { 72 SmallVectorImpl<DefinedRegular *> &V = It.second; 73 std::sort(V.begin(), V.end(), [](DefinedRegular *A, DefinedRegular *B) { 74 return A->getVA() < B->getVA(); 75 }); 76 } 77 return Ret; 78 } 79 80 // Construct a map from symbols to their stringified representations. 81 // Demangling symbols (which is what toString() does) is slow, so 82 // we do that in batch using parallel-for. 83 template <class ELFT> 84 DenseMap<DefinedRegular *, std::string> 85 getSymbolStrings(ArrayRef<DefinedRegular *> Syms) { 86 std::vector<std::string> Str(Syms.size()); 87 parallelForEachN(0, Syms.size(), [&](size_t I) { 88 raw_string_ostream OS(Str[I]); 89 writeHeader<ELFT>(OS, Syms[I]->getVA(), Syms[I]->template getSize<ELFT>(), 90 0); 91 OS << indent(2) << toString(*Syms[I]); 92 }); 93 94 DenseMap<DefinedRegular *, std::string> Ret; 95 for (size_t I = 0, E = Syms.size(); I < E; ++I) 96 Ret[Syms[I]] = std::move(Str[I]); 97 return Ret; 98 } 99 100 template <class ELFT> 101 void elf::writeMapFile(ArrayRef<OutputSection *> OutputSections) { 102 if (Config->MapFile.empty()) 103 return; 104 105 // Open a map file for writing. 106 std::error_code EC; 107 raw_fd_ostream OS(Config->MapFile, EC, sys::fs::F_None); 108 if (EC) { 109 error("cannot open " + Config->MapFile + ": " + EC.message()); 110 return; 111 } 112 113 // Collect symbol info that we want to print out. 114 std::vector<DefinedRegular *> Syms = getSymbols<ELFT>(); 115 SymbolMapTy SectionSyms = getSectionSyms<ELFT>(Syms); 116 DenseMap<DefinedRegular *, std::string> SymStr = getSymbolStrings<ELFT>(Syms); 117 118 // Print out the header line. 119 int W = ELFT::Is64Bits ? 16 : 8; 120 OS << left_justify("Address", W) << ' ' << left_justify("Size", W) 121 << " Align Out In Symbol\n"; 122 123 // Print out file contents. 124 for (OutputSection *OSec : OutputSections) { 125 writeHeader<ELFT>(OS, OSec->Addr, OSec->Size, OSec->Alignment); 126 OS << OSec->Name << '\n'; 127 128 // Dump symbols for each input section. 129 for (InputSection *IS : OSec->Sections) { 130 writeHeader<ELFT>(OS, OSec->Addr + IS->OutSecOff, IS->getSize(), 131 IS->Alignment); 132 OS << indent(1) << toString(IS) << '\n'; 133 for (DefinedRegular *Sym : SectionSyms[IS]) 134 OS << SymStr[Sym] << '\n'; 135 } 136 } 137 } 138 139 template void elf::writeMapFile<ELF32LE>(ArrayRef<OutputSection *>); 140 template void elf::writeMapFile<ELF32BE>(ArrayRef<OutputSection *>); 141 template void elf::writeMapFile<ELF64LE>(ArrayRef<OutputSection *>); 142 template void elf::writeMapFile<ELF64BE>(ArrayRef<OutputSection *>); 143