Don't replace all dominated uses if there is only one use, since that use can't be dominated, saving one domtree lookup.
Don't replace all dominated uses if there is only one use, since that
use can't be dominated, saving one domtree lookup.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@142066 91177308-0d34-0410-b5e6-96231b3b80d8

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