[Bug tree-optimization/81346] Missed constant propagation into comparison

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81346

--- Comment #12 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 41781
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=41781&action=edit
gcc8-pr81346-2.patch

Further optimization from build_range_check.