This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: builtin_bswap plus enhancements
- From: Paul Brook <paul at codesourcery dot com>
- To: Falk Hueffner <falk at debian dot org>
- Cc: Chris Lattner <clattner at apple dot com>, Eric Christopher <echristo at apple dot com>, "gcc-patches at gcc dot gnu dot org Patches" <gcc-patches at gcc dot gnu dot org>, iant at google dot com
- Date: Thu, 10 Aug 2006 20:52:04 +0100
- Subject: Re: builtin_bswap plus enhancements
- References: <44D29BA2.30206@apple.com> <2895761B-5D52-4C32-894C-B19DDFBD9F4D@apple.com> <87r6zotlzu.fsf@debian.org>
On Thursday 10 August 2006 20:43, Falk Hueffner wrote:
> Chris Lattner <clattner@apple.com> writes:
> > Why not add bswap16 as well?
>
> It should be unnecessary, since any attempt to express it should be
> picked up by the rot idiom recognizer, and the backends should then
> emit optimal code for constant-8 rots (and if that doesn't actually
> happen, we should rather fix that).
Is this true for machines that don't have HImode registers or arithmetic
operations?
Paul