| //===- MapFile.cpp --------------------------------------------------------===// |
| // |
| // The LLVM Linker |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the -Map option. It shows lists in order and |
| // hierarchically the output sections, input sections, input files and |
| // symbol: |
| // |
| // Address Size Align Out In Symbol |
| // 00201000 00000015 4 .text |
| // 00201000 0000000e 4 test.o:(.text) |
| // 0020100e 00000000 0 local |
| // 00201005 00000000 0 f(int) |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "MapFile.h" |
| #include "InputFiles.h" |
| #include "LinkerScript.h" |
| #include "OutputSections.h" |
| #include "SymbolTable.h" |
| #include "Symbols.h" |
| #include "SyntheticSections.h" |
| #include "lld/Common/Strings.h" |
| #include "lld/Common/Threads.h" |
| #include "llvm/ADT/MapVector.h" |
| #include "llvm/ADT/SetVector.h" |
| #include "llvm/Support/raw_ostream.h" |
| |
| using namespace llvm; |
| using namespace llvm::object; |
| |
| using namespace lld; |
| using namespace lld::elf; |
| |
| typedef DenseMap<const SectionBase *, SmallVector<Defined *, 4>> SymbolMapTy; |
| |
| static const std::string Indent8 = " "; // 8 spaces |
| static const std::string Indent16 = " "; // 16 spaces |
| |
| // Print out the first three columns of a line. |
| static void writeHeader(raw_ostream &OS, uint64_t VMA, uint64_t LMA, |
| uint64_t Size, uint64_t Align) { |
| if (Config->Is64) |
| OS << format("%16llx %16llx %8llx %5lld ", VMA, LMA, Size, Align); |
| else |
| OS << format("%8llx %8llx %8llx %5lld ", VMA, LMA, Size, Align); |
| } |
| |
| // Returns a list of all symbols that we want to print out. |
| static std::vector<Defined *> getSymbols() { |
| std::vector<Defined *> V; |
| for (InputFile *File : ObjectFiles) |
| for (Symbol *B : File->getSymbols()) |
| if (auto *DR = dyn_cast<Defined>(B)) |
| if (!DR->isSection() && DR->Section && DR->Section->Live && |
| (DR->File == File || DR->NeedsPltAddr || DR->Section->Bss)) |
| V.push_back(DR); |
| return V; |
| } |
| |
| // Returns a map from sections to their symbols. |
| static SymbolMapTy getSectionSyms(ArrayRef<Defined *> Syms) { |
| SymbolMapTy Ret; |
| for (Defined *DR : Syms) |
| Ret[DR->Section].push_back(DR); |
| |
| // Sort symbols by address. We want to print out symbols in the |
| // order in the output file rather than the order they appeared |
| // in the input files. |
| for (auto &It : Ret) { |
| SmallVectorImpl<Defined *> &V = It.second; |
| std::stable_sort(V.begin(), V.end(), [](Defined *A, Defined *B) { |
| return A->getVA() < B->getVA(); |
| }); |
| } |
| return Ret; |
| } |
| |
| // Construct a map from symbols to their stringified representations. |
| // Demangling symbols (which is what toString() does) is slow, so |
| // we do that in batch using parallel-for. |
| static DenseMap<Symbol *, std::string> |
| getSymbolStrings(ArrayRef<Defined *> Syms) { |
| std::vector<std::string> Str(Syms.size()); |
| parallelForEachN(0, Syms.size(), [&](size_t I) { |
| raw_string_ostream OS(Str[I]); |
| OutputSection *OSec = Syms[I]->getOutputSection(); |
| uint64_t VMA = Syms[I]->getVA(); |
| uint64_t LMA = OSec ? OSec->getLMA() + VMA - OSec->getVA(0) : 0; |
| writeHeader(OS, VMA, LMA, Syms[I]->getSize(), 1); |
| OS << Indent16 << toString(*Syms[I]); |
| }); |
| |
| DenseMap<Symbol *, std::string> Ret; |
| for (size_t I = 0, E = Syms.size(); I < E; ++I) |
| Ret[Syms[I]] = std::move(Str[I]); |
| return Ret; |
| } |
| |
| // Print .eh_frame contents. Since the section consists of EhSectionPieces, |
| // we need a specialized printer for that section. |
| // |
| // .eh_frame tend to contain a lot of section pieces that are contiguous |
| // both in input file and output file. Such pieces are squashed before |
| // being displayed to make output compact. |
| static void printEhFrame(raw_ostream &OS, OutputSection *OSec) { |
| std::vector<EhSectionPiece> Pieces; |
| |
| auto Add = [&](const EhSectionPiece &P) { |
| // If P is adjacent to Last, squash the two. |
| if (!Pieces.empty()) { |
| EhSectionPiece &Last = Pieces.back(); |
| if (Last.Sec == P.Sec && Last.InputOff + Last.Size == P.InputOff && |
| Last.OutputOff + Last.Size == P.OutputOff) { |
| Last.Size += P.Size; |
| return; |
| } |
| } |
| Pieces.push_back(P); |
| }; |
| |
| // Gather section pieces. |
| for (const CieRecord *Rec : InX::EhFrame->getCieRecords()) { |
| Add(*Rec->Cie); |
| for (const EhSectionPiece *Fde : Rec->Fdes) |
| Add(*Fde); |
| } |
| |
| // Print out section pieces. |
| for (EhSectionPiece &P : Pieces) { |
| writeHeader(OS, OSec->Addr + P.OutputOff, OSec->getLMA() + P.OutputOff, |
| P.Size, 1); |
| OS << Indent8 << toString(P.Sec->File) << ":(" << P.Sec->Name << "+0x" |
| << Twine::utohexstr(P.InputOff) + ")\n"; |
| } |
| } |
| |
| void elf::writeMapFile() { |
| if (Config->MapFile.empty()) |
| return; |
| |
| // Open a map file for writing. |
| std::error_code EC; |
| raw_fd_ostream OS(Config->MapFile, EC, sys::fs::F_None); |
| if (EC) { |
| error("cannot open " + Config->MapFile + ": " + EC.message()); |
| return; |
| } |
| |
| // Collect symbol info that we want to print out. |
| std::vector<Defined *> Syms = getSymbols(); |
| SymbolMapTy SectionSyms = getSectionSyms(Syms); |
| DenseMap<Symbol *, std::string> SymStr = getSymbolStrings(Syms); |
| |
| // Print out the header line. |
| int W = Config->Is64 ? 16 : 8; |
| OS << right_justify("VMA", W) << ' ' << right_justify("LMA", W) |
| << " Size Align Out In Symbol\n"; |
| |
| for (BaseCommand *Base : Script->SectionCommands) { |
| if (auto *Cmd = dyn_cast<SymbolAssignment>(Base)) { |
| if (Cmd->Provide && !Cmd->Sym) |
| continue; |
| //FIXME: calculate and print LMA. |
| writeHeader(OS, Cmd->Addr, 0, Cmd->Size, 1); |
| OS << Cmd->CommandString << '\n'; |
| continue; |
| } |
| |
| auto *OSec = cast<OutputSection>(Base); |
| writeHeader(OS, OSec->Addr, OSec->getLMA(), OSec->Size, OSec->Alignment); |
| OS << OSec->Name << '\n'; |
| |
| // Dump symbols for each input section. |
| for (BaseCommand *Base : OSec->SectionCommands) { |
| if (auto *ISD = dyn_cast<InputSectionDescription>(Base)) { |
| for (InputSection *IS : ISD->Sections) { |
| if (IS == InX::EhFrame) { |
| printEhFrame(OS, OSec); |
| continue; |
| } |
| |
| writeHeader(OS, IS->getVA(0), OSec->getLMA() + IS->getOffset(0), |
| IS->getSize(), IS->Alignment); |
| OS << Indent8 << toString(IS) << '\n'; |
| for (Symbol *Sym : SectionSyms[IS]) |
| OS << SymStr[Sym] << '\n'; |
| } |
| continue; |
| } |
| |
| if (auto *Cmd = dyn_cast<ByteCommand>(Base)) { |
| writeHeader(OS, OSec->Addr + Cmd->Offset, OSec->getLMA() + Cmd->Offset, |
| Cmd->Size, 1); |
| OS << Indent8 << Cmd->CommandString << '\n'; |
| continue; |
| } |
| |
| if (auto *Cmd = dyn_cast<SymbolAssignment>(Base)) { |
| if (Cmd->Provide && !Cmd->Sym) |
| continue; |
| writeHeader(OS, Cmd->Addr, OSec->getLMA() + Cmd->Addr - OSec->getVA(0), |
| Cmd->Size, 1); |
| OS << Indent8 << Cmd->CommandString << '\n'; |
| continue; |
| } |
| } |
| } |
| } |
| |
| static void print(StringRef A, StringRef B) { |
| outs() << left_justify(A, 49) << " " << B << "\n"; |
| } |
| |
| // Output a cross reference table to stdout. This is for --cref. |
| // |
| // For each global symbol, we print out a file that defines the symbol |
| // followed by files that uses that symbol. Here is an example. |
| // |
| // strlen /lib/x86_64-linux-gnu/libc.so.6 |
| // tools/lld/tools/lld/CMakeFiles/lld.dir/lld.cpp.o |
| // lib/libLLVMSupport.a(PrettyStackTrace.cpp.o) |
| // |
| // In this case, strlen is defined by libc.so.6 and used by other two |
| // files. |
| void elf::writeCrossReferenceTable() { |
| if (!Config->Cref) |
| return; |
| |
| // Collect symbols and files. |
| MapVector<Symbol *, SetVector<InputFile *>> Map; |
| for (InputFile *File : ObjectFiles) { |
| for (Symbol *Sym : File->getSymbols()) { |
| if (isa<SharedSymbol>(Sym)) |
| Map[Sym].insert(File); |
| if (auto *D = dyn_cast<Defined>(Sym)) |
| if (!D->isLocal() && (!D->Section || D->Section->Live)) |
| Map[D].insert(File); |
| } |
| } |
| |
| // Print out a header. |
| outs() << "Cross Reference Table\n\n"; |
| print("Symbol", "File"); |
| |
| // Print out a table. |
| for (auto KV : Map) { |
| Symbol *Sym = KV.first; |
| SetVector<InputFile *> &Files = KV.second; |
| |
| print(toString(*Sym), toString(Sym->File)); |
| for (InputFile *File : Files) |
| if (File != Sym->File) |
| print("", toString(File)); |
| } |
| } |