simplify some code.  If we can infer alignment for source and dest that are  greater than memcpy alignment, and if we lower to load/store, use the best  alignment info we have.
simplify some code.  If we can infer alignment for source and dest that are 
greater than memcpy alignment, and if we lower to load/store, use the best 
alignment info we have.


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@45943 91177308-0d34-0410-b5e6-96231b3b80d8

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