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Re: Status of SSE builtins
> We could also have a target macro that controls the word size (i.e.
> hard register size) being assumed for an access of a subparty in one
> mode of an entity in another mode. For SSE2 targets, you would give the
> size of the SSE2 registers.
> This value can than be used instead of UNITS_PER_WORD in the generic simd
> code - and elsewhere if appropriate - to control wheather to use subregs or
> extract_bit_field / store_bit_field.
>
> This would make the target code a lot simpler than having to write expanders
> for every extraction. Of course, that is assuming that extract_bit_field
> will work OK.
I don't think this is good idea. We will end up with something that
will move do a lot of shifting on SSE register and finally subreg it
into integer register, do arithmetic and repeat the shifting that will
be dificult to simplify into the code we should produce.
Honza
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