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/TimeProfiler.h"
  29 #include "llvm/Support/raw_ostream.h"
  30
  31 using namespace llvm;
  32 using namespace llvm::object;
  33 using namespace lld;
  34 using namespace lld::coff;
  35
  36 using SymbolMapTy =
  37     DenseMap<const SectionChunk *, SmallVector<DefinedRegular *, 4>>;
  38
  39 static constexpr char indent8[] = "        ";          // 8 spaces
  40 static constexpr char indent16[] = "                "; // 16 spaces
  41
  42 // Print out the first three columns of a line.
  43 static void writeHeader(raw_ostream &os, uint64_t addr, uint64_t size,
  44                         uint64_t align) {
  45   os << format("%08llx %08llx %5lld ", addr, size, align);
  46 }
  47
  48 // Returns a list of all symbols that we want to print out.
  49 static std::vector<DefinedRegular *> getSymbols(const COFFLinkerContext &ctx) {
  50   std::vector<DefinedRegular *> v;
  51   for (ObjFile *file : ctx.objFileInstances)
  52     for (Symbol *b : file->getSymbols())
  53       if (auto *sym = dyn_cast_or_null<DefinedRegular>(b))
  54         if (sym && !sym->getCOFFSymbol().isSectionDefinition())
  55           v.push_back(sym);
  56   return v;
  57 }
  58
  59 // Returns a map from sections to their symbols.
  60 static SymbolMapTy getSectionSyms(ArrayRef<DefinedRegular *> syms) {
  61   SymbolMapTy ret;
  62   for (DefinedRegular *s : syms)
  63     ret[s->getChunk()].push_back(s);
  64
  65   // Sort symbols by address.
  66   for (auto &it : ret) {
  67     SmallVectorImpl<DefinedRegular *> &v = it.second;
  68     std::stable_sort(v.begin(), v.end(), [](DefinedRegular *a, DefinedRegular *b) {
  69       return a->getRVA() < b->getRVA();
  70     });
  71   }
  72   return ret;
  73 }
  74
  75 // Construct a map from symbols to their stringified representations.
  76 static DenseMap<DefinedRegular *, std::string>
  77 getSymbolStrings(const COFFLinkerContext &ctx,
  78                  ArrayRef<DefinedRegular *> syms) {
  79   std::vector<std::string> str(syms.size());
  80   parallelFor((size_t)0, syms.size(), [&](size_t i) {
  81     raw_string_ostream os(str[i]);
  82     writeHeader(os, syms[i]->getRVA(), 0, 0);
  83     os << indent16 << toString(ctx, *syms[i]);
  84   });
  85
  86   DenseMap<DefinedRegular *, std::string> ret;
  87   for (size_t i = 0, e = syms.size(); i < e; ++i)
  88     ret[syms[i]] = std::move(str[i]);
  89   return ret;
  90 }
  91
  92 void lld::coff::writeLLDMapFile(const COFFLinkerContext &ctx) {
  93   if (ctx.config.lldmapFile.empty())
  94     return;
  95
  96   llvm::TimeTraceScope timeScope(".lldmap file");
  97   std::error_code ec;
  98   raw_fd_ostream os(ctx.config.lldmapFile, ec, sys::fs::OF_None);
  99   if (ec)
 100     fatal("cannot open " + ctx.config.lldmapFile + ": " + ec.message());
 101
 102   // Collect symbol info that we want to print out.
 103   std::vector<DefinedRegular *> syms = getSymbols(ctx);
 104   SymbolMapTy sectionSyms = getSectionSyms(syms);
 105   DenseMap<DefinedRegular *, std::string> symStr = getSymbolStrings(ctx, syms);
 106
 107   // Print out the header line.
 108   os << "Address  Size     Align Out     In      Symbol\n";
 109
 110   // Print out file contents.
 111   for (OutputSection *sec : ctx.outputSections) {
 112     writeHeader(os, sec->getRVA(), sec->getVirtualSize(), /*align=*/pageSize);
 113     os << sec->name << '\n';
 114
 115     for (Chunk *c : sec->chunks) {
 116       auto *sc = dyn_cast<SectionChunk>(c);
 117       if (!sc)
 118         continue;
 119
 120       writeHeader(os, sc->getRVA(), sc->getSize(), sc->getAlignment());
 121       os << indent8 << sc->file->getName() << ":(" << sc->getSectionName()
 122          << ")\n";
 123       for (DefinedRegular *sym : sectionSyms[sc])
 124         os << symStr[sym] << '\n';
 125     }
 126   }
 127 }