[Bug middle-end/66741] loops not fused nor vectorized

[aldot at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66741

--- Comment #5 from Bernhard Reutner-Fischer <aldot at gcc dot gnu.org> ---
Created attachment 35941
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=35941&action=edit
Variant perusing builtins

This is (essentially) the motivating real-world example