Use range analysis for better trip count analysis

Marking more loops as always-taken avoids generating
unnecessary new top tests while marking more loops
are non-infinite enables more optimizations. This
CL helps with these improvements. Also, some more
code is shared between induction and range analysis
and a bug with refining ranges has been fixed.

Bug: 27151190

Change-Id: Iecc0d7f32ae4779ee5424cda9dcc20816220935e
6 files changed