[BUG] to logical is broken for very aggregated

[DenisYaroshevskiy]

This:

eve/include/eve/detail/function/simd/common/to_logical.hpp

Line 67 in c8686c4

using i_t = std::conditional_t< (T::size()>=128 && sizeof(element_type_t<T>) == 1)

Will run into problems very quickly

[jfalcou]

Philosphical question : do we want to support VERY aggregated types after all ?

[DenisYaroshevskiy]

Yeah. I don't know an answer to that. I'm generally not sure about aggregation, since it's not very good. Or like 64 bytes max.

Needs a decision.

[jfalcou]

wide larger than cache lien size is useless IMHO. SO we could have :

• a maximum size in a static_assert
• a hand unrolled implementation of aggregation faster to compile

[jfalcou]

It's a bit more complicated in fact. Can't some conversion lea to more than 64 bytes ?
Like converting AVX512 float into AVX512 double will requires 2 registers for a total of 128 bytes.
Worst case, AVX512 char to AVX512 double will requires 8x registers for a total of 512 bytes.