[sledge] Revise excision of segments to witness existential size
[sledge] Revise excision of segments to witness existential size

Reviewed By: jvillard

Differential Revision: D14075517

fbshipit-source-id: a3d2e7fcf

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