[Libre-soc-dev] clamping/saturation semantics

[Luke Kenneth Casson Leighton]

On 12/11/20, Jacob Lifshay <programmerjake at gmail.com> wrote:

> mv.swizzle would be a 1 src 1 dest op.

this is probably a good idea to have regardless of whether svp64 has it.


> I think you might misunderstand:

probably :)

> from what I recall from playing around with audio code,
> the operation required would be the following translated to a sequence of 1
> or more instructions:
> read inputs at src size
> scale to account for src/dest size mismatch // if src size==dest size, this
> step isn't needed
> perform arith at higher precision
> clamp result to dest size // not src size, not any other size
> write result to dest

ok so in that context, how critical would it be to have separate mv.saturate ops

vs

arith.saturate being able to specify a saturation depth less than that
of the arithmetic operation elwidth

to assess that we need an estimate of the percentage of saturated
operations within a given audio path.

l.