Revert of [regexp] Remove IsRegExp intrinsic

src/interpreter/interpreter-intrinsics.cc

 // Copyright 2015 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/interpreter/interpreter-intrinsics.h"
 
 #include "src/code-factory.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 166 matching lines @@
 }
 
 Node* IntrinsicsHelper::IsArray(Node* input, Node* arg_count, Node* context) {
   return IsInstanceType(input, JS_ARRAY_TYPE);
 }
 
 Node* IntrinsicsHelper::IsJSProxy(Node* input, Node* arg_count, Node* context) {
   return IsInstanceType(input, JS_PROXY_TYPE);
 }
 
+Node* IntrinsicsHelper::IsRegExp(Node* input, Node* arg_count, Node* context) {
+  return IsInstanceType(input, JS_REGEXP_TYPE);
+}
+
 Node* IntrinsicsHelper::IsTypedArray(Node* input, Node* arg_count,
                                      Node* context) {
   return IsInstanceType(input, JS_TYPED_ARRAY_TYPE);
 }
 
 Node* IntrinsicsHelper::IsSmi(Node* input, Node* arg_count, Node* context) {
   // TODO(ishell): Use SelectBooleanConstant here.
   InterpreterAssembler::Variable return_value(assembler_,
                                               MachineRepresentation::kTagged);
   InterpreterAssembler::Label if_smi(assembler_), if_not_smi(assembler_),
@@ skipping 196 matching lines @@
   Node* comparison = __ Word32Equal(actual, __ Int32Constant(expected));
   __ GotoIf(comparison, &match);
   __ Abort(kWrongArgumentCountForInvokeIntrinsic);
   __ Goto(&match);
   __ Bind(&match);
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8