Turn ASSERT(!rn.is(ip)) into CHECK so the error can be caught in release mode.
Turn ASSERT(!rn.is(ip)) into CHECK so the error can be caught in release mode.

It addresses the problem of 'cmp' instruction that has the side-effect that ip register
shouldn't be used as rn.

Review URL: http://codereview.chromium.org/11323

git-svn-id: b158db1e4b4ab85d4c9e510fdef4b1e8c614b15b@810 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh,UniversalFuture/moosh