Re: [PATCH 2/1] bswap: convert get_be16, get_be32 and put_be32 to inline functions
- Date: Sun, 16 Jul 2017 06:27:04 -0400
- From: Jeff King <peff@xxxxxxxx>
- Subject: Re: [PATCH 2/1] bswap: convert get_be16, get_be32 and put_be32 to inline functions
On Sat, Jul 15, 2017 at 09:22:50PM +0200, René Scharfe wrote:
> Simplify the implementation and allow callers to use expressions with
> side-effects by turning the macros get_be16, get_be32 and put_be32 into
> inline functions.
> Signed-off-by: Rene Scharfe <l.s.r@xxxxxx>
> All these redundant casts started to bother me, so I tried to come up
> with nice and clean inline functions. Successfully? You tell me.
> They are longer, but less cluttered. Would it punish -O0 builds? Is
> it all worth it?
I do think the end result is a lot more readable. On gcc 6 at least, the
function seems to end up inlined even with -O0.
Interestingly, at -O2 even with -DNO_UNALIGNED_LOADS, gcc converts the
result to a movl and a bswap. Which is the same thing our
unaligned-loads path is trying for. I wonder if we could/should just
drop it (that _would_ punish -O0 on x86, though).