[ELF] - Do not omit common symbols when -Map is given.

[grimar]

Summary

This is PR33886,

previously we did not output common symbols to map,
patch fixes that.

[grimar]

• Added testcase.

[ruiu]

ELF/MapFile.cpp

40

Remove this typedef and inline.

60

Why do you have to check this?

[grimar]

ELF/MapFile.cpp

60

For -r/--no-define-common cases.
Otherwise getSectionSyms() would return map with key==null,
does not look clean an not useful
(see my answer in this thread to Rafael about this place).

[ruiu]

test/ELF/map-commons.s

1 ↗

(On Diff #110534)

Remove this file because the feature is tested by map-file.s

[grimar]

• Addressed comments.

[ruiu]

LGTM

ELF/MapFile.cpp

 //===----------------------------------------------------------------------===//
 
 #include "MapFile.h"
 #include "InputFiles.h"
 #include "LinkerScript.h"
 #include "OutputSections.h"
 #include "Strings.h"
 #include "SymbolTable.h"
+#include "SyntheticSections.h"
 #include "Threads.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<DefinedRegular *, 4>>
-    SymbolMapTy;
+typedef DenseMap<const SectionBase *, SmallVector<Defined *, 4>> SymbolMapTy;
 
 // Print out the first three columns of a line.
 static void writeHeader(raw_ostream &OS, uint64_t Addr, uint64_t Size,
                         uint64_t Align) {
   int W = Config->Is64 ? 16 : 8;
   OS << format("%0*llx %0*llx %5lld ", W, Addr, W, Size, Align);
 }
 
 static std::string indent(int Depth) { return std::string(Depth * 8, ' '); }
 
 // Returns a list of all symbols that we want to print out.
-template <class ELFT> static std::vector<DefinedRegular *> getSymbols() {
-  std::vector<DefinedRegular *> V;
-  for (ObjFile<ELFT> *File : ObjFile<ELFT>::Instances)
-    for (SymbolBody *B : File->getSymbols())
-      if (auto *DR = dyn_cast<DefinedRegular>(B))
+template <class ELFT> static std::vector<Defined *> getSymbols() {
+  std::vector<Defined *> V;
+  for (ObjFile<ELFT> *File : ObjFile<ELFT>::Instances) {
+    for (SymbolBody *B : File->getSymbols()) {
+      if (auto *DR = dyn_cast<DefinedRegular>(B)) {
         if (DR->getFile() == File && !DR->isSection() && DR->Section &&
             DR->Section->Live)
           V.push_back(DR);
+      } else if (auto *DC = dyn_cast<DefinedCommon>(B)) {
+        if (InX::Common)
+          V.push_back(cast<DefinedCommon>(B));
+      }
+    }
+  }
   return V;
 }
 
 // Returns a map from sections to their symbols.
-static SymbolMapTy getSectionSyms(ArrayRef<DefinedRegular *> Syms) {
+static SymbolMapTy getSectionSyms(ArrayRef<Defined *> Syms) {
   SymbolMapTy Ret;
-  for (DefinedRegular *S : Syms)
-    Ret[S->Section].push_back(S);
+  for (Defined *S : Syms) {
+    if (auto *DR = dyn_cast<DefinedRegular>(S))
+      Ret[DR->Section].push_back(S);
+    else
+      Ret[InX::Common].push_back(S);
+  }
 
   // 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<DefinedRegular *> &V = It.second;
-    std::sort(V.begin(), V.end(), [](DefinedRegular *A, DefinedRegular *B) {
-      return A->getVA() < B->getVA();
-    });
+    SmallVectorImpl<Defined *> &V = It.second;
+    std::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.
 template <class ELFT>
-static DenseMap<DefinedRegular *, std::string>
-getSymbolStrings(ArrayRef<DefinedRegular *> Syms) {
+static DenseMap<Defined *, 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]);
     writeHeader(OS, Syms[I]->getVA(), Syms[I]->template getSize<ELFT>(), 0);
     OS << indent(2) << toString(*Syms[I]);
   });
 
-  DenseMap<DefinedRegular *, std::string> Ret;
+  DenseMap<Defined *, std::string> Ret;
   for (size_t I = 0, E = Syms.size(); I < E; ++I)
     Ret[Syms[I]] = std::move(Str[I]);
   return Ret;
 }
 
 template <class ELFT> 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<DefinedRegular *> Syms = getSymbols<ELFT>();
+  std::vector<Defined *> Syms = getSymbols<ELFT>();
   SymbolMapTy SectionSyms = getSectionSyms(Syms);
-  DenseMap<DefinedRegular *, std::string> SymStr = getSymbolStrings<ELFT>(Syms);
+  DenseMap<Defined *, std::string> SymStr = getSymbolStrings<ELFT>(Syms);
 
   // Print out the header line.
   int W = ELFT::Is64Bits ? 16 : 8;
   OS << left_justify("Address", W) << ' ' << left_justify("Size", W)
      << " Align Out     In      Symbol\n";
 
   // Print out file contents.
   for (OutputSection *OSec : OutputSections) {
     writeHeader(OS, OSec->Addr, OSec->Size, OSec->Alignment);
     OS << OSec->Name << '\n';
 
     // Dump symbols for each input section.
     for (BaseCommand *Base : OSec->Commands) {
       auto *ISD = dyn_cast<InputSectionDescription>(Base);
       if (!ISD)
         continue;
       for (InputSection *IS : ISD->Sections) {
         writeHeader(OS, OSec->Addr + IS->OutSecOff, IS->getSize(),
                     IS->Alignment);
         OS << indent(1) << toString(IS) << '\n';
-        for (DefinedRegular *Sym : SectionSyms[IS])
+        for (Defined *Sym : SectionSyms[IS])
           OS << SymStr[Sym] << '\n';
       }
     }
   }
 }
 
 template void elf::writeMapFile<ELF32LE>();
 template void elf::writeMapFile<ELF32BE>();
 template void elf::writeMapFile<ELF64LE>();
 template void elf::writeMapFile<ELF64BE>();

test/ELF/map-file.s

 // CHECK-NEXT: 0000000000201012 0000000000000000     1         {{.*}}{{/|\\}}map-file.s.tmp2.o:(.text.zed)
 // CHECK-NEXT: 0000000000201012 0000000000000000     0                 zed
 // CHECK-NEXT: 0000000000201014 0000000000000000     4         {{.*}}{{/|\\}}map-file.s.tmp3.o:(.text)
 // CHECK-NEXT: 0000000000201014 0000000000000000     0                 bah
 // CHECK-NEXT: 0000000000201014 0000000000000001     4         {{.*}}{{/|\\}}map-file.s.tmp4.a(map-file.s.tmp4.o):(.text)
 // CHECK-NEXT: 0000000000201014 0000000000000000     0                 baz
 // CHECK-NEXT: 0000000000202000 0000000000000004    16 .bss
 // CHECK-NEXT: 0000000000202000 0000000000000004    16         <internal>:(COMMON)
+// CHECK-NEXT: 0000000000202000 0000000000000004     0                 common
 // CHECK-NEXT: 0000000000000000 0000000000000008     1 .comment
 // CHECK-NEXT: 0000000000000000 0000000000000008     1         <internal>:(.comment)
 // CHECK-NEXT: 0000000000000000 00000000000000f0     8 .symtab
 // CHECK-NEXT: 0000000000000000 00000000000000f0     8         <internal>:(.symtab)
 // CHECK-NEXT: 0000000000000000 0000000000000039     1 .shstrtab
 // CHECK-NEXT: 0000000000000000 0000000000000039     1         <internal>:(.shstrtab)
 // CHECK-NEXT: 0000000000000000 000000000000002f     1 .strtab
 // CHECK-NEXT: 0000000000000000 000000000000002f     1         <internal>:(.strtab)
 
 // RUN: not ld.lld %t1.o %t2.o %t3.o %t4.a -o %t -Map=/ 2>&1 \
 // RUN:  | FileCheck -check-prefix=FAIL %s
 // FAIL: cannot open map file /