Optimize bitops with non-Smi inputs. Instead of converting both inputs
to floating point and then converting back we convert directly to a
32 bit integer. In addition the bit twiddling implementation of float-
to-integer conversion has been ported from ARM. Testing has shown that
this runs faster than the x87 or SSE3 rounding instructions. This change
is IA32 only. There may be a smaller benefit from doing the same on x64.
Review URL: http://codereview.chromium.org/506052
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3492
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