Migrate some case conversion functions from JS to CPP builtins

src/bootstrapper.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/bootstrapper.h"
 
 #include "src/accessors.h"
 #include "src/api-natives.h"
 #include "src/base/ieee754.h"
 #include "src/code-stubs.h"
@@ skipping 1706 matching lines @@
     SimpleInstallFunction(prototype, "trimLeft",
                           Builtins::kStringPrototypeTrimLeft, 0, false);
     SimpleInstallFunction(prototype, "trimRight",
                           Builtins::kStringPrototypeTrimRight, 0, false);
     SimpleInstallFunction(prototype, "toLocaleLowerCase",
                           Builtins::kStringPrototypeToLocaleLowerCase, 0,
                           false);
     SimpleInstallFunction(prototype, "toLocaleUpperCase",
                           Builtins::kStringPrototypeToLocaleUpperCase, 0,
                           false);
-    SimpleInstallFunction(prototype, "toLowerCase",
-                          Builtins::kStringPrototypeToLowerCase, 0, false);
-    SimpleInstallFunction(prototype, "toUpperCase",
-                          Builtins::kStringPrototypeToUpperCase, 0, false);
+
     SimpleInstallFunction(prototype, "valueOf",
                           Builtins::kStringPrototypeValueOf, 0, true);
 
     Handle<JSFunction> iterator = SimpleCreateFunction(
         isolate, factory->NewStringFromAsciiChecked("[Symbol.iterator]"),
         Builtins::kStringPrototypeIterator, 0, true);
     iterator->shared()->set_builtin_function_id(kStringIterator);
     JSObject::AddProperty(prototype, factory->iterator_symbol(), iterator,
                           static_cast<PropertyAttributes>(DONT_ENUM));
   }
@@ skipping 2081 matching lines @@
 
 void SetFunction(Handle<JSObject> target, Handle<JSFunction> function,
                  Handle<Name> name, PropertyAttributes attributes = DONT_ENUM) {
   JSObject::SetOwnPropertyIgnoreAttributes(target, name, function, attributes)
       .ToHandleChecked();
 }
 
 }  // namespace
 
 void Genesis::InitializeGlobal_icu_case_mapping() {
-  if (!FLAG_icu_case_mapping) return;
-
-  Handle<JSReceiver> exports_container(
-      JSReceiver::cast(native_context()->exports_container()));
-
   Handle<JSObject> string_prototype(
       JSObject::cast(native_context()->string_function()->prototype()));
 
-  Handle<JSFunction> to_lower_case = Handle<JSFunction>::cast(
-      JSReceiver::GetProperty(
-          exports_container,
-          factory()->InternalizeUtf8String("ToLowerCaseI18N"))
-          .ToHandleChecked());
-  SetFunction(string_prototype, to_lower_case,
-              factory()->InternalizeUtf8String("toLowerCase"));
+  if (FLAG_icu_case_mapping) {
+    // ICU
+    Handle<JSReceiver> exports_container(
+        JSReceiver::cast(native_context()->exports_container()));
 
-  Handle<JSFunction> to_upper_case = Handle<JSFunction>::cast(
-      JSReceiver::GetProperty(
-          exports_container,
-          factory()->InternalizeUtf8String("ToUpperCaseI18N"))
-          .ToHandleChecked());
-  SetFunction(string_prototype, to_upper_case,
-              factory()->InternalizeUtf8String("toUpperCase"));
+    SimpleInstallFunction(string_prototype, "toLowerCase",
+                          Builtins::kStringPrototypeToLowerCaseI18N, 0, false);
+    SimpleInstallFunction(string_prototype, "toUpperCase",
+                          Builtins::kStringPrototypeToUpperCaseI18N, 0, false);
 
-  Handle<JSFunction> to_locale_lower_case = Handle<JSFunction>::cast(
-      JSReceiver::GetProperty(
-          exports_container,
-          factory()->InternalizeUtf8String("ToLocaleLowerCaseI18N"))
-          .ToHandleChecked());
-  SetFunction(string_prototype, to_locale_lower_case,
-              factory()->InternalizeUtf8String("toLocaleLowerCase"));
+    Handle<JSFunction> to_locale_lower_case = Handle<JSFunction>::cast(
+        JSReceiver::GetProperty(
+            exports_container,
+            factory()->InternalizeUtf8String("ToLocaleLowerCaseI18N"))
+            .ToHandleChecked());
+    SetFunction(string_prototype, to_locale_lower_case,
+                factory()->InternalizeUtf8String("toLocaleLowerCase"));
 
-  Handle<JSFunction> to_locale_upper_case = Handle<JSFunction>::cast(
-      JSReceiver::GetProperty(
-          exports_container,
-          factory()->InternalizeUtf8String("ToLocaleUpperCaseI18N"))
-          .ToHandleChecked());
-  SetFunction(string_prototype, to_locale_upper_case,
-              factory()->InternalizeUtf8String("toLocaleUpperCase"));
+    Handle<JSFunction> to_locale_upper_case = Handle<JSFunction>::cast(
+        JSReceiver::GetProperty(
+            exports_container,
+            factory()->InternalizeUtf8String("ToLocaleUpperCaseI18N"))
+            .ToHandleChecked());
+    SetFunction(string_prototype, to_locale_upper_case,
+                factory()->InternalizeUtf8String("toLocaleUpperCase"));
+
+  } else {
+    // Unibrow
+    SimpleInstallFunction(string_prototype, "toLowerCase",
+                          Builtins::kStringPrototypeToLowerCase, 0, false);
+    SimpleInstallFunction(string_prototype, "toUpperCase",
+                          Builtins::kStringPrototypeToUpperCase, 0, false);
+  }
 }
 #endif
 
 Handle<JSFunction> Genesis::InstallArrayBuffer(Handle<JSObject> target,
                                                const char* name,
                                                Builtins::Name call,
                                                BuiltinFunctionId id,
                                                bool is_shared) {
   // Create the %ArrayBufferPrototype%
   // Setup the {prototype} with the given {name} for @@toStringTag.
@@ skipping 1222 matching lines @@
 }
 
 
 // Called when the top-level V8 mutex is destroyed.
 void Bootstrapper::FreeThreadResources() {
   DCHECK(!IsActive());
 }
 
 }  // namespace internal
 }  // namespace v8