interleaved with other instructions.  Reorder the stack check
slightly to avoid some load delay. The end result is almost
imperceptible.
Review URL: http://codereview.chromium.org/181019

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2784 ce2b1a6d-e550-0410-aec6-3dcde31c8c00