xref: /llvm-project-15.0.7/lld/COFF/MapFile.cpp (revision 3141ddc5)
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 /lldmap 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     File    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 "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 
33 using namespace lld;
34 using namespace lld::coff;
35 
36 typedef DenseMap<const SectionChunk *, SmallVector<DefinedRegular *, 4>>
37     SymbolMapTy;
38 
39 // Print out the first three columns of a line.
40 static void writeHeader(raw_ostream &OS, uint64_t Addr, uint64_t Size,
41                         uint64_t Align) {
42   OS << format("%08llx %08llx %5lld ", Addr, Size, Align);
43 }
44 
45 static std::string indent(int Depth) { return std::string(Depth * 8, ' '); }
46 
47 // Returns a list of all symbols that we want to print out.
48 static std::vector<DefinedRegular *> getSymbols() {
49   std::vector<DefinedRegular *> V;
50   for (ObjFile *File : ObjFile::Instances)
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::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   for_each_n(parallel::par, (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 << indent(2) << 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 coff::writeMapFile(ArrayRef<OutputSection *> OutputSections) {
91   if (Config->MapFile.empty())
92     return;
93 
94   std::error_code EC;
95   raw_fd_ostream OS(Config->MapFile, EC, sys::fs::F_None);
96   if (EC)
97     fatal("cannot open " + Config->MapFile + ": " + EC.message());
98 
99   // Collect symbol info that we want to print out.
100   std::vector<DefinedRegular *> Syms = getSymbols();
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 : OutputSections) {
109     writeHeader(OS, Sec->getRVA(), Sec->getVirtualSize(), /*Align=*/PageSize);
110     OS << Sec->getName() << '\n';
111 
112     for (Chunk *C : Sec->getChunks()) {
113       auto *SC = dyn_cast<SectionChunk>(C);
114       if (!SC)
115         continue;
116 
117       writeHeader(OS, SC->getRVA(), SC->getSize(), SC->Alignment);
118       OS << indent(1) << SC->File->getName() << ":(" << SC->getSectionName()
119          << ")\n";
120       for (DefinedRegular *Sym : SectionSyms[SC])
121         OS << SymStr[Sym] << '\n';
122     }
123   }
124 }
125