"/job:worker/replica:0/task:0/device:XLA_GPU:1";
  std::unique_ptr<Graph> graph(new Graph(OpRegistry::Global()));
  Output a = ops::Tanh(root.WithOpName("tanh_A_dev0"),
                       ops::Const(root.WithOpName("A_dev0"), 1.0f, {2, 2}));
  Output b = ops::Tanh(root.WithOpName("tanh_B_dev1"),
                       ops::Const(root.WithOpName("B_dev1"), 1.0f, {2, 2}));
  Output matmul0 = ops::MatMul(root.WithOpName("MatMul0_dev0"), a, a);