Fix mixtral ONNX Exporter Issue. (#29858)

* fix mixtral onnx export

* fix qwen model

src/transformers/models/mixtral/modeling_mixtral.py

@@ -871,15 +871,11 @@ def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
             if top_x.shape[0] == 0:
                 continue
 
-            # in torch it is faster to index using lists than torch tensors
-            top_x_list = top_x.tolist()
-            idx_list = idx.tolist()
-
             # Index the correct hidden states and compute the expert hidden state for
             # the current expert. We need to make sure to multiply the output hidden
             # states by `routing_weights` on the corresponding tokens (top-1 and top-2)
-            current_state = hidden_states[None, top_x_list].reshape(-1, hidden_dim)
-            current_hidden_states = expert_layer(current_state) * routing_weights[top_x_list, idx_list, None]
+            current_state = hidden_states[None, top_x].reshape(-1, hidden_dim)
+            current_hidden_states = expert_layer(current_state) * routing_weights[top_x, idx, None]
 
             # However `index_add_` only support torch tensors for indexing so we'll use
             # the `top_x` tensor here.

src/transformers/models/qwen2_moe/modeling_qwen2_moe.py

@@ -843,15 +843,11 @@ def forward(self, hidden_states: torch.Tensor) -> torch.Tensor:
             if top_x.shape[0] == 0:
                 continue
 
-            # in torch it is faster to index using lists than torch tensors
-            top_x_list = top_x.tolist()
-            idx_list = idx.tolist()
-
             # Index the correct hidden states and compute the expert hidden state for
             # the current expert. We need to make sure to multiply the output hidden
             # states by `routing_weights` on the corresponding tokens (top-1 and top-2)
-            current_state = hidden_states[None, top_x_list].reshape(-1, hidden_dim)
-            current_hidden_states = expert_layer(current_state) * routing_weights[top_x_list, idx_list, None]
+            current_state = hidden_states[None, top_x].reshape(-1, hidden_dim)
+            current_hidden_states = expert_layer(current_state) * routing_weights[top_x, idx, None]
 
             # However `index_add_` only support torch tensors for indexing so we'll use
             # the `top_x` tensor here.