Delete SyntheticUndefined.

Now that resolved is templated anyway, we can use the regular Undefined.

llvm-svn: 246407

lld/ELF/SymbolTable.cpp

@@ -27,25 +27,29 @@ void SymbolTable::addFile(std::unique_ptr<InputFile> File) {
   addObject(P);
 }
 
+template <class ELFT> void SymbolTable::init() {
+  resolve<ELFT>(new (Alloc)
+                    Undefined<ELFT>("_start", Undefined<ELFT>::Synthetic));
+}
+
 void SymbolTable::addObject(ObjectFileBase *File) {
   if (!ObjectFiles.empty()) {
     ObjectFileBase &Old = *ObjectFiles[0];
     if (!Old.isCompatibleWith(*File))
       error(Twine(Old.getName() + " is incompatible with " + File->getName()));
   } else {
-    auto *Start = new (Alloc) SyntheticUndefined("_start");
     switch (File->kind()) {
     case InputFile::Object32LEKind:
-      resolve<ELF32LE>(Start);
+      init<ELF32LE>();
       break;
     case InputFile::Object32BEKind:
-      resolve<ELF32BE>(Start);
+      init<ELF32BE>();
       break;
     case InputFile::Object64LEKind:
-      resolve<ELF64LE>(Start);
+      init<ELF64LE>();
       break;
     case InputFile::Object64BEKind:
-      resolve<ELF64BE>(Start);
+      init<ELF64BE>();
       break;
     }
   }

lld/ELF/SymbolTable.h

@@ -51,6 +51,7 @@ public:
 private:
   void addObject(ObjectFileBase *File);
 
+  template <class ELFT> void init();
   template <class ELFT> void resolve(SymbolBody *Body);
 
   llvm::DenseMap<StringRef, Symbol *> Symtab;

lld/ELF/Symbols.h

@@ -42,16 +42,13 @@ public:
     DefinedAbsoluteKind = 1,
     DefinedCommonKind = 2,
     DefinedLast = 2,
-    UndefinedKind = 3,
-    UndefinedSyntheticKind = 4
+    UndefinedKind = 3
   };
 
   Kind kind() const { return static_cast<Kind>(SymbolKind); }
 
   bool isWeak() const { return IsWeak; }
-  bool isUndefined() const {
-    return SymbolKind == UndefinedKind || SymbolKind == UndefinedSyntheticKind;
-  }
+  bool isUndefined() const { return SymbolKind == UndefinedKind; }
   bool isDefined() const { return !isUndefined(); }
   bool isStrongUndefined() const { return !IsWeak && isUndefined(); }
   bool isCommon() const { return SymbolKind == DefinedCommonKind; }
@@ -166,22 +163,14 @@ public:
   const SectionChunk<ELFT> &Section;
 };
 
-// Undefined symbols.
-class SyntheticUndefined : public SymbolBody {
-public:
-  explicit SyntheticUndefined(StringRef N)
-      : SymbolBody(UndefinedKind, N, false) {}
-
-  static bool classof(const SymbolBody *S) {
-    return S->kind() == UndefinedSyntheticKind;
-  }
-};
-
+// Undefined symbol.
 template <class ELFT> class Undefined : public ELFSymbolBody<ELFT> {
   typedef ELFSymbolBody<ELFT> Base;
   typedef typename Base::Elf_Sym Elf_Sym;
 
 public:
+  static Elf_Sym Synthetic;
+
   explicit Undefined(StringRef N, const Elf_Sym &Sym)
       : ELFSymbolBody<ELFT>(Base::UndefinedKind, N, Sym) {}
 
@@ -190,6 +179,9 @@ public:
   }
 };
 
+template <class ELFT>
+typename Undefined<ELFT>::Elf_Sym Undefined<ELFT>::Synthetic;
+
 } // namespace elf2
 } // namespace lld
 

lld/ELF/Writer.cpp

@@ -302,8 +302,6 @@ template <class ELFT> void SymbolTableSection<ELFT>::writeTo(uint8_t *Buf) {
     const Elf_Sym *InputSym = nullptr;
 
     switch (Body->kind()) {
-    case SymbolBody::UndefinedSyntheticKind:
-      llvm_unreachable("Should be defined by now");
     case SymbolBody::DefinedRegularKind: {
       auto *Def = cast<DefinedRegular<ELFT>>(Body);
       InputSym = &Def->Sym;