From: "Randy Brukardt" <randy@rrsoftware.com>
Subject: Re: AI12-0218: What is the portable representation clause for processing IETF packets on little-endian machines?
Date: Mon, 14 May 2018 17:54:52 -0500
Date: 2018-05-14T17:54:52-05:00 [thread overview]
Message-ID: <pdd43t$uhf$1@franka.jacob-sparre.dk> (raw)
In-Reply-To: 87lgcphdxq.fsf@nightsong.com
"Paul Rubin" <no.email@nospam.invalid> wrote in message
news:87lgcphdxq.fsf@nightsong.com...
> "Randy Brukardt" <randy@rrsoftware.com> writes:
>> I don't know of any way on the x86 processor of reading a byte-swapped
>> 32-bit integer into a register so it can be used.
>
> Load it into a register, then BSWAP. This could be made into a compiler
> intrinsic if necessary. GCC has __builtin_bswap16, __builtin_bswap32,
> and __builtin_bswap64 for this purpose.
What's "BSWAP"? It's not an instruction I'm familar with on x86.
(Admittedly, I don't usually use newer instructions because of the need to
have some sort of alternative to run on older processors.)
In any case, one has to build such support into the back-end. (Compiler
front-ends are almost always target-independent.) "intrinsics" are just a
fancy way of identifying things that are directly supported in the back-end.
Randy.
next prev parent reply other threads:[~2018-05-14 22:54 UTC|newest]
Thread overview: 63+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-10 17:45 AI12-0218: What is the portable representation clause for processing IETF packets on little-endian machines? Dan'l Miller
2018-05-10 19:24 ` Dan'l Miller
2018-05-10 20:32 ` Paul Rubin
2018-05-10 22:24 ` Dan'l Miller
2018-05-10 22:44 ` Niklas Holsti
2018-05-10 23:14 ` Paul Rubin
2018-05-11 2:38 ` Dan'l Miller
2018-05-11 7:55 ` Simon Wright
2018-05-11 12:11 ` Lucretia
2018-05-11 13:49 ` Simon Wright
2018-05-11 16:11 ` Jeffrey R. Carter
2018-05-11 16:48 ` Simon Wright
2018-05-11 19:08 ` Jeffrey R. Carter
2018-05-11 21:39 ` Simon Wright
2018-05-11 21:56 ` Jeffrey R. Carter
2018-05-12 7:08 ` Simon Wright
2018-05-12 7:53 ` Jeffrey R. Carter
2018-05-14 22:43 ` Randy Brukardt
2018-05-11 13:46 ` Simon Wright
2018-05-11 22:12 ` Randy Brukardt
2018-05-12 10:33 ` Björn Lundin
2018-05-12 13:08 ` Simon Wright
2018-05-12 14:21 ` Björn Lundin
2018-05-10 23:07 ` Paul Rubin
2018-05-11 0:14 ` Dan'l Miller
2018-05-11 0:30 ` Paul Rubin
2018-05-11 0:50 ` Dan'l Miller
2018-05-11 1:34 ` Paul Rubin
2018-05-11 2:11 ` Dan'l Miller
2018-05-11 22:32 ` Randy Brukardt
2018-05-11 8:02 ` Simon Wright
2018-05-11 22:14 ` Randy Brukardt
2018-05-10 19:28 ` Simon Wright
2018-05-10 22:40 ` Randy Brukardt
2018-05-10 22:50 ` Dan'l Miller
2018-05-11 22:00 ` Randy Brukardt
2018-05-12 1:15 ` Paul Rubin
2018-05-14 22:54 ` Randy Brukardt [this message]
2018-05-15 0:43 ` Paul Rubin
2018-05-15 21:39 ` Randy Brukardt
2018-05-15 0:44 ` Dennis Lee Bieber
2018-05-11 8:09 ` Simon Wright
2018-05-10 19:34 ` Dmitry A. Kazakov
2018-05-10 20:06 ` Dan'l Miller
2018-05-10 22:44 ` Paul Rubin
2018-05-10 22:50 ` Randy Brukardt
2018-05-11 9:40 ` Niklas Holsti
2018-05-11 11:40 ` Dan'l Miller
2018-05-11 20:16 ` Niklas Holsti
2018-05-11 9:40 ` Dmitry A. Kazakov
2018-05-11 14:21 ` AdaMagica
2018-05-26 16:15 ` Dan'l Miller
2018-05-26 19:02 ` AdaMagica
2018-05-26 21:01 ` Dan'l Miller
2018-05-27 14:58 ` AdaMagica
2018-05-27 18:03 ` Simon Wright
2018-05-29 22:17 ` Randy Brukardt
2018-05-30 6:39 ` Simon Wright
2018-05-30 7:25 ` Dmitry A. Kazakov
2018-05-30 15:01 ` Simon Wright
2018-05-30 15:59 ` Dan'l Miller
2018-05-30 19:38 ` Randy Brukardt
2018-05-27 18:04 ` Dan'l Miller
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