[Bug tree-optimization/31178] VRP can infer a range for b in a >> b and a << b

[jakub at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=31178

--- Comment #21 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Yes, though I think we should fix the Fortran FE so that it only relies on [0,
N) .  If the shift count is constant, it can deal with it at compile time, if
it is variable, can emit a COND_EXPR for the shift_count == N case.