Revert my previous work on ArgumentPromotion.  Further investigation has revealed these changes to be incorrect.  They just weren't showing up in any of our current testcases.
Revert my previous work on ArgumentPromotion.  Further investigation has revealed these
changes to be incorrect.  They just weren't showing up in any of our current testcases.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@30385 91177308-0d34-0410-b5e6-96231b3b80d8

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