[Bug tree-optimization/67975] Failure to optimise equality between two call sequences

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67975

--- Comment #3 from Richard Biener <rguenth at gcc dot gnu.org> ---
I have a prototype that handles (extended) diamonds.  With this FRE1 is able to
optimize the check to 1 (with -O -ffast-math).