[Bug tree-optimization/68021] [6 Regression] ice in rewrite_use_nonlinear_expr with -O3

[amker at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68021

--- Comment #15 from amker at gcc dot gnu.org ---
Though the previous patch can work, I am testing another patch less intrusive.