Adapt SubArray indices

[maleadt]

julia> view(CuArray([1]), CuArray([1]))
1-element view(::CuArray{Int64,1}, [1]) with eltype Int64:
 1

julia> parentindices(ans)
([1],)

julia> typeof(ans)
Tuple{CuArray{Int64,1}}

The indices needs an adapt as well:

Adapt.adapt_structure(to, A::SubArray{<:Any,<:Any,AT}) where {AT} = SubArray(adapt(to, parent(A)), adapt.(Ref(to), parentindices(A)))

Reported by @ali-ramadhan

[maleadt]

This is actually a little more complex, because the view constructor does bounds checking:

julia> view(CuArray([1]), CuArray([1]))
ERROR: scalar getindex is disallowed

[maleadt]

This is an old issue, so I'm not exactly sure what the problem was, but we adapt the SubArray indices now:

julia> Adapt.adapt(CuArray, view([1], [1]))
1-element view(::CuArray{Int64, 1, CUDA.DeviceMemory}, [1]) with eltype Int64:
 1

julia> typeof(ans)
SubArray{Int64, 1, CuArray{Int64, 1, CUDA.DeviceMemory}, Tuple{CuArray{Int64, 1, CUDA.DeviceMemory}}, false}