[lldb] abi_tag support 3/4 - Add char const* overload for SymbolNameFitsToLanguage

[Michael137]

Summary

This patch adds a new overload to Language::SymbolNameFitsToLanguage
that only requires a char const* parameter instead of a Mangled
object. This is useful for future efforts in which parts of the
CPlusPlusLanguage plugin will avoid using Mangled in favour
of the Itanium mangle tree API.

[Michael137]

• Rebase

[aprantl]

lldb/include/lldb/Target/Language.h

210

1. Would it be worth hiding this implementation detail inside the function? Ie., would it make sense to pass a Mangled and then have the implementation of SymbolNameFitsToLanguage extract the raw mangled string from it?

2. We usually try to avoid APIs that take a char * and use StringRefs. Or is the cxx demangler API using char * too?

[Michael137]

lldb/include/lldb/Target/Language.h

210

Would it be worth hiding this implementation detail inside the function? Ie., would it make sense to pass a Mangled and then have the implementation of SymbolNameFitsToLanguage extract the raw mangled string from it?

I wanted to avoid creating a Mangled object in the code-path where we use the mangle tree API since we'd then be demangling the function symbol twice. But you're right, we can just keep this in class CPlusPlusLanguage I plan to only use it there.

We usually try to avoid APIs that take a char * and use StringRefs. Or is the cxx demangler API using char * too?

Yup StringRef would make sense

lldb/include/lldb/Target/Language.h

public:
   };
 
   /// Returns true iff the given symbol name is compatible with the mangling
   /// scheme of this language.
   ///
   /// This function should only return true if there is a high confidence
   /// that the name actually belongs to this language.
   virtual bool SymbolNameFitsToLanguage(Mangled name) const { return false; }
+  virtual bool SymbolNameFitsToLanguage(char const *mangled) const {
+    return false;
+  }
 
   // if an individual data formatter can apply to several types and cross a
   // language boundary it makes sense for individual languages to want to
   // customize the printing of values of that type by appending proper
   // prefix/suffix information in language-specific ways
   virtual bool GetFormatterPrefixSuffix(ValueObject &valobj,
                                         ConstString type_hint,
                                         std::string &prefix,

lldb/source/Plugins/Language/CPlusPlus/CPlusPlusLanguage.h

public:
 
   static void Terminate();
 
   static lldb_private::Language *CreateInstance(lldb::LanguageType language);
 
   static llvm::StringRef GetPluginNameStatic() { return "cplusplus"; }
 
   bool SymbolNameFitsToLanguage(Mangled mangled) const override;
-  
+  bool SymbolNameFitsToLanguage(char const *mangled) const override;
   bool DemangledNameContainsPath(llvm::StringRef path, 
                                  ConstString demangled) const override;
 
   ConstString
   GetDemangledFunctionNameWithoutArguments(Mangled mangled) const override;
 
   static bool IsCPPMangledName(llvm::StringRef name);
 

lldb/source/Plugins/Language/CPlusPlus/CPlusPlusLanguage.cpp

void CPlusPlusLanguage::Terminate() {
   PluginManager::UnregisterPlugin(CreateInstance);
 }
 
 bool CPlusPlusLanguage::SymbolNameFitsToLanguage(Mangled mangled) const {
   const char *mangled_name = mangled.GetMangledName().GetCString();
   return mangled_name && CPlusPlusLanguage::IsCPPMangledName(mangled_name);
 }
 
+bool CPlusPlusLanguage::SymbolNameFitsToLanguage(char const *mangled) const {
+  return mangled && CPlusPlusLanguage::IsCPPMangledName(mangled);
+}
+
 ConstString CPlusPlusLanguage::GetDemangledFunctionNameWithoutArguments(
     Mangled mangled) const {
   const char *mangled_name_cstr = mangled.GetMangledName().GetCString();
   ConstString demangled_name = mangled.GetDemangledName();
   if (demangled_name && mangled_name_cstr && mangled_name_cstr[0]) {
     if (mangled_name_cstr[0] == '_' && mangled_name_cstr[1] == 'Z' &&
         (mangled_name_cstr[2] != 'T' && // avoid virtual table, VTT structure,
                                         // typeinfo structure, and typeinfo