[regexp] Add additional asserts to RegExp builtins

src/code-stub-assembler.cc

 // Copyright 2016 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/code-stub-assembler.h"
 #include "src/code-factory.h"
 #include "src/frames-inl.h"
 #include "src/frames.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 3087 matching lines @@
 
 Node* CodeStubAssembler::IsFixedTypedArray(Node* object) {
   Node* instance_type = LoadInstanceType(object);
   return Word32And(
       Int32GreaterThanOrEqual(instance_type,
                               Int32Constant(FIRST_FIXED_TYPED_ARRAY_TYPE)),
       Int32LessThanOrEqual(instance_type,
                            Int32Constant(LAST_FIXED_TYPED_ARRAY_TYPE)));
 }
 
+Node* CodeStubAssembler::IsJSRegExp(Node* object) {
+  return HasInstanceType(object, JS_REGEXP_TYPE);
+}
+
 Node* CodeStubAssembler::StringCharCodeAt(Node* string, Node* index,
                                           ParameterMode parameter_mode) {
   CSA_ASSERT(this, IsString(string));
 
   // Translate the {index} into a Word.
   Node* const int_index = ParameterToWord(index, parameter_mode);
 
   Variable var_result(this, MachineRepresentation::kWord32);
 
   Label out(this, &var_result), runtime_generic(this), runtime_external(this);
@@ skipping 5349 matching lines @@
         formatted.c_str(), TENURED);
     CallRuntime(Runtime::kGlobalPrint, NoContextConstant(),
                 HeapConstant(string));
   }
   CallRuntime(Runtime::kDebugPrint, NoContextConstant(), tagged_value);
 #endif
 }
 
 }  // namespace internal
 }  // namespace v8