Re: [Qemu-devel] [PATCH 01/10] target-arm: Make Neon helper routines use correct FP status

[Peter Maydell <peter.maydell@linaro.org>]

On 3 April 2011 12:10, Blue Swirl <blauwirbel@gmail.com> wrote:
> On Sun, Apr 3, 2011 at 1:51 PM, Peter Maydell <peter.maydell@linaro.org> wrote:
>> But I can submit a patch to do that if it's the right thing.
>
> It's not so much about correctness, but performance. All generated
> code already has access to global env, so passing it via helper
> arguments requires extra instructions which can be avoided.

Yes; I meant "right thing" in the more general senses of "is best
practice for qemu code" and "causes my patches to be accepted" :-)

Anyway, how about I do a version of this patch which moves
the affected neon helpers to op_helper.c rather than adding
an env parameter (which would avoid changes that a cleanup
would just have to revert); but leave patch 10 as-is (that's
the one which is touching vfp helpers, but it is just cleanup
which isn't changing how they handle env) ?

Then I can do a separate patchset to move other helpers,
rather than tangling a code-cleanup patchset with Neon
correctness fixes.

-- PMM