llvm calling convention matters

Geoffrey Mainland mainland at apeiron.net
Wed Sep 11 23:40:20 UTC 2013

On 09/11/2013 07:33 PM, Johan Tibell wrote:
> On Wed, Sep 11, 2013 at 3:59 PM, Geoffrey Mainland <mainland at apeiron.net> wrote:
>     I don't see why we should limit ourselves by insisting that the gap
>     between what the LLVM back-end and the native back-end not grow
>     If we want SIMD, the gap is already quite large. Yes it would be
nice to
>     have feature parity, but there are only so many man-hours
available, and
>     we want to invest them wisely. The SIMD primops already do not work on
>     the native codegen; the user gets an error telling them to use the
>     back-end if they use the SIMD primops with the native codegen.
> Having conditional primops makes for lots of ugly #ifdefs everywhere
> and everyone need to make sure they do these correctly. We don't have
> to implement SIMD in the native backend, we just need to have some
> reasonable emulation e.g. see how MO_PopCnt has a C fallback or how
> Int64 falls back to C code.

Do you mean we need a reasonable emulation of the SIMD primops for the
native codegen?


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