Fix KernelAbstractions for Unified Memory (#316)

Author: tgymnich

src/MetalKernels.jl

@@ -35,20 +35,20 @@ Adapt.adapt_storage(::KA.CPU, a::MtlArray) = convert(Array, a)
 
 function KA.copyto!(::MetalBackend, A::MtlArray{T}, B::MtlArray{T}) where T
     if device(dest) == device(src)
-        GC.@preserve A B unsafe_copyto!(device(A), pointer(A), pointer(B), length(A); async=true)
+        GC.@preserve A B copyto!(A, B)
         return A
     else
         error("Copy between different devices not implemented")
     end
 end
 
 function KA.copyto!(::MetalBackend, A::Array{T}, B::MtlArray{T}) where T
-    GC.@preserve A B unsafe_copyto!(device(B), pointer(A), pointer(B), length(A); async=true)
+    GC.@preserve A B copyto!(A, B)
     return A
 end
 
 function KA.copyto!(::MetalBackend, A::MtlArray{T}, B::Array{T}) where T
-    GC.@preserve A B unsafe_copyto!(device(A), pointer(A), pointer(B), length(A); async=true)
+    GC.@preserve A B copyto!(A, B)
     return A
 end
 

src/array.jl

@@ -181,7 +181,6 @@ end
 
 function Base.unsafe_convert(::Type{MtlPointer{T}}, x::MtlArray) where {T}
    buf = x.data[]
-   synchronize()
    MtlPointer{T}(buf, x.offset*Base.elsize(x))
  end