with simd, is it possible to have an array `ar` where i could index on with a vector `ar[vector]`?

[velvet gulch]

each element of vector would be a index in ar
the ar contains f32's which i would want to sum with @reduce (i think)

[halcyon briar]

you’ve discovered gathering, use @shuffle for exactly this
although if you’re summing them up, why do you need to gather?

or uh, to revise my original answer, i’d vector comptime known?

[velvet gulch]

ar is comptime known, vector is filled during runtime

[halcyon briar]

then just do like
for (0..N) |i| out[i] = ar[vector[i]]

[velvet gulch]

but then i'd be making the vector for nothing

[halcyon briar]

1. not really? it’ll still generate a vpshuf
2. what are you actually trying to achieve?

[velvet gulch]

1. whats that?
2. i want to 'parallel' (idk if thats correct terminology) indexing on a array. im reading characters from a line, i use those characters to index on ar which' values i need to sum

[halcyon briar]

1. x86 instruction that does gather
2. you need to sum the values at the given indices? is it a constant amount of items per line?

[velvet gulch]

1. ah so it would still do some performance optimizations?
2. the items per line differ

[velvet gulch]

wouldnt it be better to just do sum += ... instead of out[i] = ... first?

[halcyon briar]

i mean, yeah