Revert of [regexp] Remove IsRegExp intrinsic

src/interpreter/interpreter-intrinsics.h

 // 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.
 
 #ifndef V8_INTERPRETER_INTERPRETER_INTRINSICS_H_
 #define V8_INTERPRETER_INTERPRETER_INTRINSICS_H_
 
 #include "src/allocation.h"
 #include "src/builtins/builtins.h"
 #include "src/frames.h"
@@ skipping 12 matching lines @@
 
 // List of supported intrisics, with upper case name, lower case name and
 // expected number of arguments (-1 denoting argument count is variable).
 #define INTRINSICS_LIST(V)                              \
   V(Call, call, -1)                                     \
   V(ClassOf, class_of, 1)                               \
   V(HasProperty, has_property, 2)                       \
   V(IsArray, is_array, 1)                               \
   V(IsJSProxy, is_js_proxy, 1)                          \
   V(IsJSReceiver, is_js_receiver, 1)                    \
+  V(IsRegExp, is_regexp, 1)                             \
   V(IsSmi, is_smi, 1)                                   \
   V(IsTypedArray, is_typed_array, 1)                    \
   V(NewObject, new_object, 2)                           \
   V(NumberToString, number_to_string, 1)                \
   V(RegExpExec, reg_exp_exec, 4)                        \
   V(SubString, sub_string, 3)                           \
   V(ToString, to_string, 1)                             \
   V(ToLength, to_length, 1)                             \
   V(ToInteger, to_integer, 1)                           \
   V(ToNumber, to_number, 1)                             \
@@ skipping 49 matching lines @@
   InterpreterAssembler* assembler_;
 
   DISALLOW_COPY_AND_ASSIGN(IntrinsicsHelper);
 };
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif