Include Base.Slice when determining view contiguity (#666)

Author: tam724

src/host/base.jl

@@ -278,9 +278,11 @@ struct NonContiguous end
 GPUIndexStyle() = Contiguous()
 GPUIndexStyle(I...) = NonContiguous()
 GPUIndexStyle(::Union{Base.ScalarIndex, CartesianIndex}...) = Contiguous()
-GPUIndexStyle(i1::Colon, ::Union{Base.ScalarIndex, CartesianIndex}...) = Contiguous()
-GPUIndexStyle(i1::AbstractUnitRange, ::Union{Base.ScalarIndex, CartesianIndex}...) = Contiguous()
-GPUIndexStyle(i1::Colon, I...) = GPUIndexStyle(I...)
+GPUIndexStyle(::Colon, ::Union{Base.ScalarIndex, CartesianIndex}...) = Contiguous()
+GPUIndexStyle(::Base.Slice, ::Union{Base.ScalarIndex, CartesianIndex}...) = Contiguous()
+GPUIndexStyle(::AbstractUnitRange, ::Union{Base.ScalarIndex, CartesianIndex}...) = Contiguous()
+GPUIndexStyle(::Colon, I...) = GPUIndexStyle(I...)
+GPUIndexStyle(::Base.Slice, I...) = GPUIndexStyle(I...)
 
 viewlength() = ()
 @inline viewlength(::Real, I...) = viewlength(I...) # skip scalar

test/testsuite/base.jl

@@ -333,11 +333,20 @@ end
       end
 
       @test compare(x->view(x, :, 1:4, 3), AT, rand(Float32, 5, 4, 3))
+      @test compare(x->view(x, Base.Slice(Base.OneTo(5)), 1:4, 3), AT, rand(Float32, 5, 4, 3))
 
       let x = AT(rand(Float32, 5, 4, 3))
         @test_throws BoundsError view(x, :, :, 1:10)
       end
 
+      @testset "selectdim" begin
+        @test compare(x -> selectdim(x, 3, 1), AT, rand(Float32, 2, 2, 2))
+        let x = AT(rand(Float32, 5, 4, 3))
+          @test typeof(selectdim(x, 3, 1)) == typeof(view(x, :, :, 1))         
+          @test typeof(selectdim(x, 2, 1)) == typeof(view(x, :, 1, :))
+        end
+      end
+
       # bug in parentindices conversion
       let x = AT{Int}(undef, 1, 1)
         x[1,:] .= 42