[lldb][NFC] use llvm::StringRef in ExtractContextAndIdentifer function (#169506)

this avoids allocation when checking if a method contains a path.

Author: da-viper

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

@@ -84,7 +84,7 @@ CPlusPlusLanguage::GetFunctionNameInfo(ConstString name) const {
   if (basename.empty()) {
     llvm::StringRef context;
     func_name_type |=
-        (ExtractContextAndIdentifier(name.GetCString(), context, basename)
+        (ExtractContextAndIdentifier(name.GetStringRef(), context, basename)
              ? (eFunctionNameTypeMethod | eFunctionNameTypeBase)
              : eFunctionNameTypeFull);
   } else {
@@ -546,9 +546,8 @@ bool CPlusPlusLanguage::CxxMethodName::ContainsPath(llvm::StringRef path) {
 
   llvm::StringRef identifier;
   llvm::StringRef context;
-  std::string path_str = path.str();
-  bool success = CPlusPlusLanguage::ExtractContextAndIdentifier(
-      path_str.c_str(), context, identifier);
+  const bool success =
+      CPlusPlusLanguage::ExtractContextAndIdentifier(path, context, identifier);
   if (!success)
     return m_full.GetStringRef().contains(path);
 
@@ -592,7 +591,8 @@ bool CPlusPlusLanguage::DemangledNameContainsPath(llvm::StringRef path,
 }
 
 bool CPlusPlusLanguage::ExtractContextAndIdentifier(
-    const char *name, llvm::StringRef &context, llvm::StringRef &identifier) {
+    llvm::StringRef name, llvm::StringRef &context,
+    llvm::StringRef &identifier) {
   if (MSVCUndecoratedNameParser::IsMSVCUndecoratedName(name))
     return MSVCUndecoratedNameParser::ExtractContextAndIdentifier(name, context,
                                                                   identifier);

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

@@ -154,7 +154,7 @@ class CPlusPlusLanguage : public Language {
   // C/C++ identifier, then it will return false
   // and identifier and context will be unchanged.
 
-  static bool ExtractContextAndIdentifier(const char *name,
+  static bool ExtractContextAndIdentifier(llvm::StringRef name,
                                           llvm::StringRef &context,
                                           llvm::StringRef &identifier);
 

lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp

@@ -2341,7 +2341,7 @@ void SymbolFileDWARF::FindGlobalVariables(
   bool name_is_mangled = Mangled::GetManglingScheme(name.GetStringRef()) !=
                          Mangled::eManglingSchemeNone;
 
-  if (!CPlusPlusLanguage::ExtractContextAndIdentifier(name.GetCString(),
+  if (!CPlusPlusLanguage::ExtractContextAndIdentifier(name.GetStringRef(),
                                                       context, basename))
     basename = name.GetStringRef();
 

lldb/unittests/Language/CPlusPlus/CPlusPlusLanguageTest.cpp

@@ -341,7 +341,7 @@ TEST(CPlusPlusLanguage, ExtractContextAndIdentifier) {
   llvm::StringRef context, basename;
   for (const auto &test : test_cases) {
     EXPECT_TRUE(CPlusPlusLanguage::ExtractContextAndIdentifier(
-        test.input.c_str(), context, basename));
+        test.input, context, basename));
     EXPECT_EQ(test.context, context.str());
     EXPECT_EQ(test.basename, basename.str());
   }