Fix rocblas errors

src/targets/gpu/gemm.cpp

@@ -32,10 +32,37 @@ void generic_rocblas_gemm(shape::as<T>, Ts&&...)
     MIGRAPH_THROW("Type unsupported by rocblas");
 }
 
+template<class T>
+struct compute_rocblas_type
+{
+    using type = T;
+};
+
+template<class T>
+struct compute_rocblas_type<const T>
+{
+    using type = const typename compute_rocblas_type<T>::type;
+};
+
+template<>
+struct compute_rocblas_type<half>
+{
+    using type = rocblas_half;
+};
+
+template<class T>
+using rb_type = typename compute_rocblas_type<T>::type;
+
+template <class T>
+rb_type<T> to_rocblas_type(T x)
+{
+    return reinterpret_cast<const rb_type<T>&>(x);
+}
+
 template <class T>
-T to_rocblas_type(T x)
+rb_type<T>* to_rocblas_type(T* x)
 {
-    return x;
+    return reinterpret_cast<rb_type<T>*>(x);
 }
 
 rocblas_half to_rocblas_type(half x) { return reinterpret_cast<const rocblas_half&>(x); }
@@ -62,6 +89,9 @@ argument miopen_gemm::compute(context& ctx,
     output_shape.visit_type([&](auto as) {
         auto alpha_r = to_rocblas_type(as(alpha));
         auto beta_r  = to_rocblas_type(as(beta));
+        auto to_pointer = [&](auto&& arg) {
+            return to_rocblas_type(as.from(arg.data()));
+        };
         generic_rocblas_gemm(as,
                              ctx.get_stream().get_rocblas(),
                              transb ? rocblas_operation_transpose : rocblas_operation_none,
@@ -70,12 +100,12 @@ argument miopen_gemm::compute(context& ctx,
                              m,
                              k,
                              &alpha_r,
-                             args[1].implicit(),
+                             to_pointer(args[1]),
                              ldb,
-                             args[0].implicit(),
+                             to_pointer(args[0]),
                              lda,
                              &beta_r,
-                             args[2].implicit(),
+                             to_pointer(args[2]),
                              ldc);
 
     });