[Bug tree-optimization/58195] Missed optimization opportunity when returning a conditional

[glisse at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58195

--- Comment #3 from Marc Glisse <glisse at gcc dot gnu.org> ---
This looks like the unary version of:
http://gcc.gnu.org/ml/gcc-patches/2014-03/msg00014.html

and something that could be auto-generated from a pattern like:
(cond (ne @0 0) (negate @0) 0) -> (negate @0)
;-)