+ return Identifier::fromString(vm, m_string.characters8(), m_string.length());
+
+ return Identifier::fromString(vm, m_string.characters16(), m_string.length());
+}
+
+const UChar* OpaqueJSString::characters()
+{
+ // m_characters is put in a local here to avoid an extra atomic load.
+ UChar* characters = m_characters;
+ if (characters)
+ return characters;
+
+ if (m_string.isNull())
+ return nullptr;
+
+ unsigned length = m_string.length();
+ UChar* newCharacters = static_cast<UChar*>(fastMalloc(length * sizeof(UChar)));
+ StringView(m_string).getCharactersWithUpconvert(newCharacters);
+
+ if (!m_characters.compare_exchange_strong(characters, newCharacters)) {
+ fastFree(newCharacters);
+ return characters;
+ }
+
+ return newCharacters;
+}
+
+bool OpaqueJSString::equal(const OpaqueJSString* a, const OpaqueJSString* b)
+{
+ if (a == b)
+ return true;
+
+ if (!a || !b)
+ return false;