Revert of Remove obsolete JSFunction::IsOptimizable predicate.

src/objects-inl.h

 // Copyright 2012 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.
 //
 // Review notes:
 //
 // - The use of macros in these inline functions may seem superfluous
 // but it is absolutely needed to make sure gcc generates optimal
 // code. gcc is not happy when attempting to inline too deep.
 //
@@ skipping 5988 matching lines @@
   return shared()->internal_formal_parameter_count() !=
          SharedFunctionInfo::kDontAdaptArgumentsSentinel;
 }
 
 
 bool JSFunction::IsOptimized() {
   return code()->kind() == Code::OPTIMIZED_FUNCTION;
 }
 
 
+bool JSFunction::IsOptimizable() {
+  return code()->kind() == Code::FUNCTION && !shared()->optimization_disabled();
+}
+
+
 bool JSFunction::IsMarkedForOptimization() {
   return code() == GetIsolate()->builtins()->builtin(
       Builtins::kCompileOptimized);
 }
 
 
 bool JSFunction::IsMarkedForConcurrentOptimization() {
   return code() == GetIsolate()->builtins()->builtin(
       Builtins::kCompileOptimizedConcurrent);
 }
@@ skipping 1591 matching lines @@
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 #undef NOBARRIER_READ_BYTE_FIELD
 #undef NOBARRIER_WRITE_BYTE_FIELD
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_