Bug fixes for JIT loop detection and formation

Specifically:
- Don't apply loop optimization if the basic induction variable is
  manipulated (ie excluding cases like "i+=0")
- Fix a case where variables reloaded with constants in the body are
  not considered as loop invariants

Bug: 2804188
Change-Id: Ia5ebb29bc6814b1be069e23794585f8313900b7d
4 files changed