Avoid overdeep recursion in regexp where a guarded expression with a

test/mjsunit/regexp-capture-3.js

 // Copyright 2012 the V8 project authors. All rights reserved.
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 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
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@@ skipping 198 matching lines @@
 
 var regex9 = new RegExp(re);
 regex9.exec(input0);
 
 var regex10 = new RegExp(re, "i");
 regex10.exec(input0);
 
 var regex11 = /^(?:[^\u0000-\u0080]|[0-9a-z?,.!&\s#()])+$/i;
 regex11.exec(input0);
 
+var regex12 = /u(\xf0{8}?\D*?|( ? !)$h??(|)*?(||)+?\6((?:\W\B|--\d-*-|)?$){0, }?|^Y( ? !1)\d+)+a/;
+regex12.exec("");