Revert unintended change to vadd example script.

examples/vadd.jl

@@ -2,33 +2,21 @@ using Test
 using Metal
 
 function vadd(a, b, c)
-    i0 = Tuple(thread_position_in_grid_3d())
-    stride = Tuple(threads_per_grid_3d())
-    is = i0
-    while 1 <= is[1] <= size(a, 1) &&
-          1 <= is[2] <= size(a, 2) &&
-          1 <= is[3] <= size(a, 3)
-        I = CartesianIndex(is)
-        c[I] = a[I] + b[I]
-        is = (is[1] + stride[1],
-              is[2] + stride[2],
-              is[3] + stride[3])
-    end
+    i = thread_position_in_grid_1d()
+    c[i] = a[i] + b[i]
     return
 end
 
-function main()
-    dims = (3,4,5)
-    a = round.(rand(Float32, dims) * 100)
-    b = round.(rand(Float32, dims) * 100)
-    c = similar(a)
+dims = (3,4)
+a = round.(rand(Float32, dims) * 100)
+b = round.(rand(Float32, dims) * 100)
+c = similar(a)
 
-    d_a = MtlArray(a)
-    d_b = MtlArray(b)
-    d_c = MtlArray(c)
+d_a = MtlArray(a)
+d_b = MtlArray(b)
+d_c = MtlArray(c)
 
-    len = prod(dims)
-    @metal threads=dims vadd(d_a, d_b, d_c)
-    c = Array(d_c)
-    @test a+b ≈ c
-end
+len = prod(dims)
+@metal threads=len vadd(d_a, d_b, d_c)
+c = Array(d_c)
+@test a+b ≈ c