[Bug c/92716] -Os doesn't inline byteswap function even though it's a single instruction

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92716

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
Most likely what is happening is the following:
inlining happens twice but the detection of bswap does not happen until after
both inlining so the cost huestric for byteswap function is high.