This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: Proposal for merging scalar-storage-order branch into mainline
- From: Richard Biener <richard dot guenther at gmail dot com>
- To: Eric Botcazou <ebotcazou at adacore dot com>
- Cc: GCC Development <gcc at gcc dot gnu dot org>
- Date: Tue, 9 Jun 2015 12:52:16 +0200
- Subject: Re: Proposal for merging scalar-storage-order branch into mainline
- Authentication-results: sourceware.org; auth=none
- References: <2354857 dot 0uXrE6NL1R at polaris> <CAFiYyc0fmZcb1SYm5NfObE-bL3T0Z0vs6yNraesAfH+jb90pHA at mail dot gmail dot com> <24307404 dot yEd3bIJVu1 at polaris>
On Tue, Jun 9, 2015 at 12:39 PM, Eric Botcazou <ebotcazou@adacore.com> wrote:
>> What's the reason to not expose the byte swapping operations earlier, like
>> on GIMPLE? (or even on GENERIC?)
>
> That would be too heavy, every load and store in GENERIC/GIMPLE would have an
> associated byte swapping operation, although you don't know if they will be
> needed in the end. For example, if the structure is scalarized, they are not.
Yes, but I'd expect them to be optimized away (well, hopefully).
Anwyay, and I thought
use of the feature would be rare so that "every load and store" is
still very few?
I suppose doing the lowering somewhen during the GIMPLE optimization pipeline
would still be possible to address missed-optimization concerns.
>> What frontends are affected?
>
> The branch contains a working implementation for the C and Ada front-ends, and
> the beginning of an implementation for the C++ front-end.
Ok, I see.
Richard.
> --
> Eric Botcazou