fix directml backend

modules/sd_offload.py

@@ -162,6 +162,12 @@ class OffloadHook(accelerate.hooks.ModelHook):
             if device_map is None or max_memory != getattr(module, "balanced_offload_max_memory", None):
                 device_map = accelerate.infer_auto_device_map(module, max_memory=max_memory)
             offload_dir = getattr(module, "offload_dir", os.path.join(shared.opts.accelerate_offload_path, module.__class__.__name__))
+            keys = device_map.keys()
+            for v in keys:
+                if isinstance(device_map[v], int):
+                    # int implies CUDA device, but it will break DirectML backend.
+                    # Therefore, the type of device should be added.
+                    device_map[v] = f"{devices.device.type}:{device_map[v]}"
             module = accelerate.dispatch_model(module, device_map=device_map, offload_dir=offload_dir)
             module._hf_hook.execution_device = torch.device(devices.device) # pylint: disable=protected-access
             module.balanced_offload_device_map = device_map