https://gcc.gnu.org/bugzilla/show_bug.cgi?id=99520
--- Comment #4 from ktkachov at gcc dot gnu.org ---
(In reply to Jakub Jelinek from comment #3)
> Consider e.g.
> unsigned foo (unsigned x)
> {
> return (x<<24) + ((x<<8)&0xff0000) + ((x>>8)&0xff00) + (x>>24) +
> (((x&0xff00)<<16)>>8);
> }
> as example that should not be optimized into __builtin_bswap32 (but should
> be with | instead of +).
interesting. That said, clang does do a better job than GCC on that too:
foo(unsigned int): // @foo(unsigned int)
lsl w9, w0, #8
rev w8, w0
and w9, w9, #0xff0000
add w0, w9, w8
ret
