Allocation in SROCK2 solver

[axsk]

StochasticDiffEq.jl/src/perform_step/SROCK_perform_step.jl

Line 428 in 11f3a3c

WikRange .= 1//2 .* (W.dW .* WikJ .- (1:length(W.dW) .== i) .* dt )#.+ (1:length(W.dW) .< i) .* dt .* WikJ2 .- (1:length(W.dW) .> i) .* dt .* vec_χ)

The line in question is allocating zeros
In my case the allocation makes up for 6% of total solver time.

Not a huge thing but I thought I'd bring it up.

[ChrisRackauckas]

I don't see how that line is allocating zeros, it looks like it should just build a range (cheap) and then broadcast the whole line?

[axsk]

I would not have seen it without the VSCode @profview

[ChrisRackauckas]

Oh it's allocating a bit array somewhere? That's wild. Yeah...

[axsk]

Thats the right allocation. To the left there is a call to

function (-)(B::BitArray)
    A = zeros(Int, size(B))
    ...
end

in bitarray.jl, L1149.
Does this mean the broadcast is not working?

[ChrisRackauckas]

Try moving the range construction to another line and then doing @..