Revert of [regexp] Remove IsRegExp intrinsic

src/crankshaft/hydrogen.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.
 
 #ifndef V8_CRANKSHAFT_HYDROGEN_H_
 #define V8_CRANKSHAFT_HYDROGEN_H_
 
 #include "src/accessors.h"
 #include "src/allocation.h"
 #include "src/ast/ast-type-bounds.h"
@@ skipping 2138 matching lines @@
     function_state()->ClearInlinedTestContext();
   }
   LanguageMode function_language_mode() {
     return function_state()->compilation_info()->parse_info()->language_mode();
   }
 
 #define FOR_EACH_HYDROGEN_INTRINSIC(F) \
   F(IsSmi)                             \
   F(IsArray)                           \
   F(IsTypedArray)                      \
+  F(IsRegExp)                          \
   F(IsJSProxy)                         \
   F(Call)                              \
   F(NewObject)                         \
   F(ToInteger)                         \
   F(ToObject)                          \
   F(ToString)                          \
   F(ToLength)                          \
   F(ToNumber)                          \
   F(IsJSReceiver)                      \
   F(DebugBreakInOptimizedCode)         \
@@ skipping 812 matching lines @@
   }
 
  private:
   HOptimizedGraphBuilder* builder_;
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CRANKSHAFT_HYDROGEN_H_