lld/COFF/LLDMapFile.cpp

   1 //===- LLDMapFile.cpp -----------------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This file implements the /lldmap option. It shows lists in order and
  10 // hierarchically the output sections, input sections, input files and
  11 // symbol:
  12 //
  13 //   Address  Size     Align Out     File    Symbol
  14 //   00201000 00000015     4 .text
  15 //   00201000 0000000e     4         test.o:(.text)
  16 //   0020100e 00000000     0                 local
  17 //   00201005 00000000     0                 f(int)
  18 //
  19 //===----------------------------------------------------------------------===//
  20
  21 #include "LLDMapFile.h"
  22 #include "COFFLinkerContext.h"
  23 #include "SymbolTable.h"
  24 #include "Symbols.h"
  25 #include "Writer.h"
  26 #include "lld/Common/ErrorHandler.h"
  27 #include "llvm/Support/Parallel.h"
  28 #include "llvm/Support/raw_ostream.h"
  29
  30 using namespace llvm;
  31 using namespace llvm::object;
  32 using namespace lld;
  33 using namespace lld::coff;
  34
  35 using SymbolMapTy =
  36     DenseMap<const SectionChunk *, SmallVector<DefinedRegular *, 4>>;
  37
  38 static constexpr char indent8[] = "        ";          // 8 spaces
  39 static constexpr char indent16[] = "                "; // 16 spaces
  40
  41 // Print out the first three columns of a line.
  42 static void writeHeader(raw_ostream &os, uint64_t addr, uint64_t size,
  43                         uint64_t align) {
  44   os << format("%08llx %08llx %5lld ", addr, size, align);
  45 }
  46
  47 // Returns a list of all symbols that we want to print out.
  48 static std::vector<DefinedRegular *> getSymbols(const COFFLinkerContext &ctx) {
  49   std::vector<DefinedRegular *> v;
  50   for (ObjFile *file : ctx.objFileInstances)
  51     for (Symbol *b : file->getSymbols())
  52       if (auto *sym = dyn_cast_or_null<DefinedRegular>(b))
  53         if (sym && !sym->getCOFFSymbol().isSectionDefinition())
  54           v.push_back(sym);
  55   return v;
  56 }
  57
  58 // Returns a map from sections to their symbols.
  59 static SymbolMapTy getSectionSyms(ArrayRef<DefinedRegular *> syms) {
  60   SymbolMapTy ret;
  61   for (DefinedRegular *s : syms)
  62     ret[s->getChunk()].push_back(s);
  63
  64   // Sort symbols by address.
  65   for (auto &it : ret) {
  66     SmallVectorImpl<DefinedRegular *> &v = it.second;
  67     std::stable_sort(v.begin(), v.end(), [](DefinedRegular *a, DefinedRegular *b) {
  68       return a->getRVA() < b->getRVA();
  69     });
  70   }
  71   return ret;
  72 }
  73
  74 // Construct a map from symbols to their stringified representations.
  75 static DenseMap<DefinedRegular *, std::string>
  76 getSymbolStrings(ArrayRef<DefinedRegular *> syms) {
  77   std::vector<std::string> str(syms.size());
  78   parallelForEachN((size_t)0, syms.size(), [&](size_t i) {
  79     raw_string_ostream os(str[i]);
  80     writeHeader(os, syms[i]->getRVA(), 0, 0);
  81     os << indent16 << toString(*syms[i]);
  82   });
  83
  84   DenseMap<DefinedRegular *, std::string> ret;
  85   for (size_t i = 0, e = syms.size(); i < e; ++i)
  86     ret[syms[i]] = std::move(str[i]);
  87   return ret;
  88 }
  89
  90 void lld::coff::writeLLDMapFile(const COFFLinkerContext &ctx) {
  91   if (config->lldmapFile.empty())
  92     return;
  93
  94   std::error_code ec;
  95   raw_fd_ostream os(config->lldmapFile, ec, sys::fs::OF_None);
  96   if (ec)
  97     fatal("cannot open " + config->lldmapFile + ": " + ec.message());
  98
  99   // Collect symbol info that we want to print out.
 100   std::vector<DefinedRegular *> syms = getSymbols(ctx);
 101   SymbolMapTy sectionSyms = getSectionSyms(syms);
 102   DenseMap<DefinedRegular *, std::string> symStr = getSymbolStrings(syms);
 103
 104   // Print out the header line.
 105   os << "Address  Size     Align Out     In      Symbol\n";
 106
 107   // Print out file contents.
 108   for (OutputSection *sec : ctx.outputSections) {
 109     writeHeader(os, sec->getRVA(), sec->getVirtualSize(), /*align=*/pageSize);
 110     os << sec->name << '\n';
 111
 112     for (Chunk *c : sec->chunks) {
 113       auto *sc = dyn_cast<SectionChunk>(c);
 114       if (!sc)
 115         continue;
 116
 117       writeHeader(os, sc->getRVA(), sc->getSize(), sc->getAlignment());
 118       os << indent8 << sc->file->getName() << ":(" << sc->getSectionName()
 119          << ")\n";
 120       for (DefinedRegular *sym : sectionSyms[sc])
 121         os << symStr[sym] << '\n';
 122     }
 123   }
 124 }