tighten up checks
tighten up checks

We manage to generate all of the matching instructions (and a lot more) via
the reciprocal optimization function - even if we completely remove the square
root optimization. With CHECK_NEXT, we assure that we're executing the
expected square root optimization paths and not generating extra insts.



git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@218284 91177308-0d34-0410-b5e6-96231b3b80d8

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