Check for contiguous dim order in op_fast_hadamard_transform (#5419)

Summary:
Pull Request resolved: #5419

Lunwen pointed out we didn't handle this case.
ghstack-source-id: 243051227
exported-using-ghexport

Reviewed By: helunwencser

Differential Revision: D62788230

fbshipit-source-id: d8e892d84f6a1a4631818a9bbafd9c98d28edc1b

Author: swolchok

extension/llm/custom_ops/op_fast_hadamard_transform.cpp

@@ -34,6 +34,18 @@ Tensor& fast_hadamard_transform_out(
     return out;
   }
 
+  ET_KERNEL_CHECK(
+      ctx,
+      is_contiguous_dim_order(mat.dim_order().data(), mat.dim()),
+      InvalidArgument,
+      out);
+
+  ET_KERNEL_CHECK(
+      ctx,
+      is_contiguous_dim_order(out.dim_order().data(), out.dim()),
+      InvalidArgument,
+      out);
+
   ET_KERNEL_CHECK_MSG(
       ctx,
       mat.strides().back() == 1,