add notes

Author: vchuravy

src/nditeration.jl

@@ -85,6 +85,11 @@ Base.@propagate_inbounds function expand(ndrange::NDRange{N}, groupidx::Integer,
     # expand(ndrange, blocks(ndrange)[groupidx], workitems(ndrange)[idx])
 
     # The formulation below saves one sdiv
+    # but leads to a different index order...
+    # previous: julia> expand(ndrange, 1, 32*32)
+    #                  CartesianIndex(32, 32)
+    # now:      julia> expand(ndrange, 1, 32*32)
+    #                  CartesianIndex(1024, 1)
     B = blocks(ndrange)
     W = workitems(ndrange)
     Ind = ntuple(Val(N)) do I