[Bug tree-optimization/55177] missed optimizations with __builtin_bswap

[ubizjak at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55177

--- Comment #18 from Uroš Bizjak <ubizjak at gmail dot com> ---
(In reply to David Woodhouse from comment #17)

> unsigned or(struct pkt *p)

gcc 5.0 optimizes the above case ...

> unsigned add(struct pkt *p)

... but not this one.  Probably just the case of missing match.pd pattern.