[Bug tree-optimization/113189] `(-X * Y) * -X` can be optimized to `(X * Y) * X`

[jsm28 at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=113189

--- Comment #2 from Joseph S. Myers <jsm28 at gcc dot gnu.org> ---
If Y is INT_MIN and X is -1, removing the negations introduces undefined
behavior in the first example (-(-1) * INT_MIN * -(-1) is valid, -1 * INT_MIN *
-1 has undefined behavior).

For floating types, removing the negations isn't valid if flag_rounding_math.