Merge branch 'k2-fsa:master' into dev/speechllm

Author: yfyeung

egs/librispeech/ASR/zipformer/model.py

@@ -210,10 +210,10 @@ def forward_cr_ctc(
         )
 
         # Compute consistency regularization loss
-        exchanged_targets = ctc_output.detach().chunk(2, dim=0)
-        exchanged_targets = torch.cat(
-            [exchanged_targets[1], exchanged_targets[0]], dim=0
-        )  # exchange: [x1, x2] -> [x2, x1]
+        batch_size = ctc_output.shape[0]
+        assert batch_size % 2 == 0, batch_size
+        # exchange: [x1, x2] -> [x2, x1]
+        exchanged_targets = torch.roll(ctc_output.detach(), batch_size // 2, dims=0)
         cr_loss = nn.functional.kl_div(
             input=ctc_output,
             target=exchanged_targets,