[Bug tree-optimization/89518] missed optimisation for array address calculations

[glisse at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89518

--- Comment #2 from Marc Glisse <glisse at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #1)
> We do not have a (a / b) * b + (a % b) simplification rule.

Indeed. That's surprising since we do have for trunc_div
/* X - (X / Y) * Y is the same as X % Y.  */