[Bug tree-optimization/80898] [8 Regression] wrong code at -O2 and -O3 in both 32-bit and 64-bit modes on x86_64-linux-gnu

[jamborm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80898

--- Comment #5 from Martin Jambor <jamborm at gcc dot gnu.org> ---
Created attachment 41443
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=41443&action=edit
First fix

This patch fixes the issue, but I think I can now think of a slightly
more complicated scenario in which it would not be enough, I will try
to come up with a testcase and fix it too.