[Bug rtl-optimization/70542] [6 Regression] Wrong code with -O3 -mavx2.

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70542

--- Comment #5 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 38190
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=38190&action=edit
gcc6-pr70542.patch

Untested fix.