Only keep the global split candidates that work out.
Only keep the global split candidates that work out.

Some pysical registers create split solutions that would spill anywhere.
They should not even be considered in future multi-way global splits.

This does not affect code generation (yet).

git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@135080 91177308-0d34-0410-b5e6-96231b3b80d8

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