Assert kernel layout

topi/python/topi/x86/conv2d.py

@@ -415,15 +415,17 @@ def _alter_conv2d_layout(attrs, inputs, tinfo, F):
 
     dtype = data.dtype
     out_dtype = dtype if out_dtype in ("same", "") else out_dtype
-    kshape = get_const_tuple(kernel.shape)
-    is_depthwise = groups == kshape[0] and kshape[1] == 1
 
     # only optimize for NCHW
     if layout != 'NCHW':
         return None
     if groups != 1 and not is_depthwise:
         return None
 
+    assert attrs["kernel_layout"] == "OIHW"
+    kshape = get_const_tuple(kernel.shape)
+    is_depthwise = groups == kshape[0] and kshape[1] == 1
+
     dispatch_ctx = autotvm.task.DispatchContext.current
     target = tvm.target.current_target()
     # query schedule and fallback if necessary