Subzero: Assemble calls to constant addresses.

src/IceELFSection.cpp

 //===- subzero/src/IceELFSection.cpp - Representation of ELF sections -----===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file defines how ELF sections are represented.
@@ skipping 62 matching lines @@
     F.set_position(BaseOff + F.position());
   }
 }
 
 size_t ELFRelocationSection::getSectionDataSize() const {
   return Fixups.size() * Header.sh_entsize;
 }
 
 // Symbol tables.
 
+void ELFSymbolTableSection::createNullSymbol(ELFSection *NullSection) {
+  // The first entry in the symbol table should be a NULL entry,
+  // so make sure the map is still empty.
+  assert(LocalSymbols.empty());
+  const IceString NullSymName("");
+  createDefinedSym(NullSymName, STT_NOTYPE, STB_LOCAL, NullSection, 0, 0);
+  NullSymbol = findSymbol(NullSymName);
+}
+
 void ELFSymbolTableSection::createDefinedSym(const IceString &Name,
                                              uint8_t Type, uint8_t Binding,
                                              ELFSection *Section,
                                              RelocOffsetT Offset, SizeT Size) {
   ELFSym NewSymbol = ELFSym();
   NewSymbol.Sym.setBindingAndType(Binding, Type);
   NewSymbol.Sym.st_value = Offset;
   NewSymbol.Sym.st_size = Size;
   NewSymbol.Section = Section;
   NewSymbol.Number = ELFSym::UnknownNumber;
   bool Unique;
   if (Binding == STB_LOCAL)
     Unique = LocalSymbols.insert(std::make_pair(Name, NewSymbol)).second;
   else
     Unique = GlobalSymbols.insert(std::make_pair(Name, NewSymbol)).second;
   assert(Unique);
   (void)Unique;
 }
 
 void ELFSymbolTableSection::noteUndefinedSym(const IceString &Name,
                                              ELFSection *NullSection) {
   ELFSym NewSymbol = ELFSym();
   NewSymbol.Sym.setBindingAndType(STB_GLOBAL, STT_NOTYPE);
   NewSymbol.Section = NullSection;
   NewSymbol.Number = ELFSym::UnknownNumber;
-  GlobalSymbols.insert(std::make_pair(Name, NewSymbol));
+  bool Unique = GlobalSymbols.insert(std::make_pair(Name, NewSymbol)).second;
+  assert(Unique);
+  (void)Unique;
 }
 
 const ELFSym *ELFSymbolTableSection::findSymbol(const IceString &Name) const {
   auto I = LocalSymbols.find(Name);
   if (I != LocalSymbols.end())
     return &I->second;
   I = GlobalSymbols.find(Name);
   if (I != GlobalSymbols.end())
     return &I->second;
   return nullptr;
@@ skipping 83 matching lines @@
       continue;
     }
     StringIndex.second = StringData.size();
     std::copy(Cur.begin(), Cur.end(), back_inserter(StringData));
     StringData.push_back(0);
     Prev = Cur;
   }
 }
 
 } // end of namespace Ice