Don't include shared libraries multiple times.

llvm-svn: 249061

lld/ELF/InputFiles.cpp

@@ -77,13 +77,14 @@ ELFData<ELFT>::getSymbolsHelper(bool Local) {
   return make_range(Syms.begin() + 1, Syms.begin() + FirstNonLocal);
 }
 
-template <class ELFT>
-typename ELFData<ELFT>::Elf_Sym_Range ELFData<ELFT>::getNonLocalSymbols() {
-  if (!Symtab)
-    return Elf_Sym_Range(nullptr, nullptr);
+template <class ELFT> void ELFData<ELFT>::initStringTable() {
   ErrorOr<StringRef> StringTableOrErr = ELFObj.getStringTableForSymtab(*Symtab);
   error(StringTableOrErr.getError());
   StringTable = *StringTableOrErr;
+}
+
+template <class ELFT>
+typename ELFData<ELFT>::Elf_Sym_Range ELFData<ELFT>::getNonLocalSymbols() {
   return getSymbolsHelper(false);
 }
 
@@ -141,6 +142,7 @@ template <class ELFT> void elf2::ObjectFile<ELFT>::initializeSections() {
 }
 
 template <class ELFT> void elf2::ObjectFile<ELFT>::initializeSymbols() {
+  this->initStringTable();
   Elf_Sym_Range Syms = this->getNonLocalSymbols();
   uint32_t NumSymbols = std::distance(Syms.begin(), Syms.end());
   SymbolBodies.reserve(NumSymbols);
@@ -233,7 +235,7 @@ template <class ELFT>
 SharedFile<ELFT>::SharedFile(MemoryBufferRef M)
     : SharedFileBase(getStaticELFKind<ELFT>(), M), ELFData<ELFT>(M) {}
 
-template <class ELFT> void SharedFile<ELFT>::parse() {
+template <class ELFT> void SharedFile<ELFT>::parseSoName() {
   typedef typename ELFFile<ELFT>::Elf_Dyn Elf_Dyn;
   typedef typename ELFFile<ELFT>::uintX_t uintX_t;
   const Elf_Shdr *DynamicSec = nullptr;
@@ -247,8 +249,7 @@ template <class ELFT> void SharedFile<ELFT>::parse() {
       DynamicSec = &Sec;
   }
 
-  // Also sets StringTable
-  Elf_Sym_Range Syms = this->getNonLocalSymbols();
+  this->initStringTable();
   SoName = getName();
 
   if (DynamicSec) {
@@ -266,7 +267,10 @@ template <class ELFT> void SharedFile<ELFT>::parse() {
       }
     }
   }
+}
 
+template <class ELFT> void SharedFile<ELFT>::parse() {
+  Elf_Sym_Range Syms = this->getNonLocalSymbols();
   uint32_t NumSymbols = std::distance(Syms.begin(), Syms.end());
   SymbolBodies.reserve(NumSymbols);
   for (const Elf_Sym &Sym : Syms) {

lld/ELF/InputFiles.h

@@ -116,6 +116,7 @@ protected:
   llvm::object::ELFFile<ELFT> ELFObj;
   const Elf_Shdr *Symtab = nullptr;
   StringRef StringTable;
+  void initStringTable();
   Elf_Sym_Range getNonLocalSymbols();
   Elf_Sym_Range getSymbolsHelper(bool);
 };
@@ -194,6 +195,7 @@ public:
       : ELFFileBase(SharedKind, EKind, M) {}
   static bool classof(const InputFile *F) { return F->kind() == SharedKind; }
   StringRef getSoName() const { return SoName; }
+  virtual void parseSoName() = 0;
 };
 
 template <class ELFT>
@@ -217,6 +219,7 @@ public:
 
   explicit SharedFile(MemoryBufferRef M);
 
+  void parseSoName() override;
   void parse() override;
 };
 

lld/ELF/SymbolTable.cpp

@@ -41,6 +41,11 @@ void SymbolTable::addFile(std::unique_ptr<InputFile> File) {
       addLazy(&Sym);
     return;
   }
+  if (auto *S = dyn_cast<SharedFileBase>(File.get())) {
+    S->parseSoName();
+    if (!IncludedSoNames.insert(S->getSoName()).second)
+      return;
+  }
   File->parse();
   addELFFile(cast<ELFFileBase>(File.release()));
 }

lld/ELF/SymbolTable.h

@@ -93,6 +93,7 @@ private:
   std::vector<std::unique_ptr<ObjectFileBase>> ObjectFiles;
 
   std::vector<std::unique_ptr<SharedFileBase>> SharedFiles;
+  llvm::DenseSet<StringRef> IncludedSoNames;
 
   SymbolBody *EntrySym = nullptr;
 };

lld/test/elf2/soname.s

@@ -1,9 +1,10 @@
 // RUN: llvm-mc -filetype=obj -triple=x86_64-pc-linux %s -o %t.o
 // RUN: lld -flavor gnu2 %t.o -shared -soname=bar -o %t.so
-// RUN: lld -flavor gnu2 %t.o %t.so -o %t
+// RUN: lld -flavor gnu2 %t.o %t.so %t.so -o %t
 // RUN: llvm-readobj --dynamic-table %t | FileCheck %s
 
 // CHECK:  0x0000000000000001 NEEDED               SharedLibrary (bar)
+// CHECK-NOT: NEEDED
 
 .global _start
 _start: