[sledge] Simplify `e xor e` to `0`
[sledge] Simplify `e xor e` to `0`

Reviewed By: bennostein

Differential Revision: D17665226

fbshipit-source-id: 655ddf6a8

facebook/infer,jvillard/infer,facebook/infer,jvillard/infer,jvillard/infer,facebook/infer,jvillard/infer,jvillard/infer,facebook/infer,facebook/infer,facebook/infer,jvillard/infer,jvillard/infer,facebook/infer