[llvm-objcopy] Delete redundant !Config.xx.empty() when followed by positive is_contained() check

[MaskRay]

Summary

The original intention of !Config.xx.empty() was probably to emphasize the thing that is currently considered, but I feel the simplified form is actually easier to understand and it is also consistent with the call sites in other llvm components.

[alexander-shaposhnikov]

Thanks for cleaning this up.

tools/llvm-objcopy/ELF/ELFObjcopy.cpp

static void handleArgs(const CopyConfig &Config, Object &Obj,
 
   // TODO: update or remove symbols only if there is an option that affects
   // them.
   if (Obj.SymbolTable) {
     Obj.SymbolTable->updateSymbols([&](Symbol &Sym) {
       if (!Sym.isCommon() &&
           ((Config.LocalizeHidden &&
             (Sym.Visibility == STV_HIDDEN || Sym.Visibility == STV_INTERNAL)) ||
-           (!Config.SymbolsToLocalize.empty() &&
-            is_contained(Config.SymbolsToLocalize, Sym.Name))))
+           is_contained(Config.SymbolsToLocalize, Sym.Name)))
         Sym.Binding = STB_LOCAL;
 
       // Note: these two globalize flags have very similar names but different
       // meanings:
       //
       // --globalize-symbol: promote a symbol to global
       // --keep-global-symbol: all symbols except for these should be made local
       //
       // If --globalize-symbol is specified for a given symbol, it will be
       // global in the output file even if it is not included via
       // --keep-global-symbol. Because of that, make sure to check
       // --globalize-symbol second.
       if (!Config.SymbolsToKeepGlobal.empty() &&
           !is_contained(Config.SymbolsToKeepGlobal, Sym.Name) &&
           Sym.getShndx() != SHN_UNDEF)
         Sym.Binding = STB_LOCAL;
 
-      if (!Config.SymbolsToGlobalize.empty() &&
-          is_contained(Config.SymbolsToGlobalize, Sym.Name) &&
+      if (is_contained(Config.SymbolsToGlobalize, Sym.Name) &&
           Sym.getShndx() != SHN_UNDEF)
         Sym.Binding = STB_GLOBAL;
 
-      if (!Config.SymbolsToWeaken.empty() &&
-          is_contained(Config.SymbolsToWeaken, Sym.Name) &&
+      if (is_contained(Config.SymbolsToWeaken, Sym.Name) &&
           Sym.Binding == STB_GLOBAL)
         Sym.Binding = STB_WEAK;
 
       if (Config.Weaken && Sym.Binding == STB_GLOBAL &&
           Sym.getShndx() != SHN_UNDEF)
         Sym.Binding = STB_WEAK;
 
       const auto I = Config.SymbolsToRename.find(Sym.Name);
       if (I != Config.SymbolsToRename.end())
         Sym.Name = I->getValue();
 
       if (!Config.SymbolsPrefix.empty() && Sym.Type != STT_SECTION)
         Sym.Name = (Config.SymbolsPrefix + Sym.Name).str();
     });
 
     // The purpose of this loop is to mark symbols referenced by sections
     // (like GroupSection or RelocationSection). This way, we know which
     // symbols are still 'needed' and which are not.
     if (Config.StripUnneeded) {
       for (auto &Section : Obj.sections())
         Section.markSymbols();
     }
 
     Obj.removeSymbols([&](const Symbol &Sym) {
-      if ((!Config.SymbolsToKeep.empty() &&
-           is_contained(Config.SymbolsToKeep, Sym.Name)) ||
+      if (is_contained(Config.SymbolsToKeep, Sym.Name) ||
           (Config.KeepFileSymbols && Sym.Type == STT_FILE))
         return false;
 
       if (Config.DiscardAll && Sym.Binding == STB_LOCAL &&
           Sym.getShndx() != SHN_UNDEF && Sym.Type != STT_FILE &&
           Sym.Type != STT_SECTION)
         return true;
 
       if (Config.StripAll || Config.StripAllGNU)
         return true;
 
-      if (!Config.SymbolsToRemove.empty() &&
-          is_contained(Config.SymbolsToRemove, Sym.Name)) {
+      if (is_contained(Config.SymbolsToRemove, Sym.Name))
         return true;
-      }
 
       if (Config.StripUnneeded && !Sym.Referenced &&
           (Sym.Binding == STB_LOCAL || Sym.getShndx() == SHN_UNDEF) &&
           Sym.Type != STT_FILE && Sym.Type != STT_SECTION)
         return true;
 
       return false;
     });