[Bug rtl-optimization/78546] [6/7 Regression] wrong code at -O2 and above

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78546

--- Comment #12 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Therefore the comment should be
/* CST1 - (CST2 - A) -> (CST1 - CST2) - A  */
rather than
/* CST - (CST - A) -> CST - A  */