Re: [Qemu-devel] QEmu TCG SIMD extension?

[Peter Maydell]

On 6 March 2013 16:18, Paolo Bonzini <address@hidden> wrote:
> Il 06/03/2013 04:47, Peter Maydell ha scritto:
>> I think my opinions are still the same -- interesting idea, but getting
>> it to work with a set of IR ops which aren't target or host specific
>> and getting it to give correct bit-for-bit results, rounding, flags,
>> etc, is likely to be tricky. It would also be important to determine
>> first whether Neon (or other SIMD) emulation performance is truly
>> a major bottleneck.
>
> SSE operations, while not a bottleneck, are the top helpers in the
> profile when booting Linux on x86.
>
> Using common code to generate the simplest unrolled SIMD operations
> (logical operations, add, subtract, compare to zero) would already help
> a lot, I think.

Yeah, I don't mean to say it's a bad idea, just that there's a long
distance between a neat tech demo/research paper and productised
code that can be committed to mainline :-)

-- PMM