Fold trunc(any_ext).  This gives stuff like:
Fold trunc(any_ext).  This gives stuff like:

27,28c27
<       movzwl %di, %edi
<       movl %edi, %ebx
---
>       movw %di, %bx


git-svn-id: 0ff597fd157e6f4fc38580e8d64ab130330d2411@28137 91177308-0d34-0410-b5e6-96231b3b80d8

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