Fixed: Only compare the 0 index after ensuring that the content exists.

Author: JamePeng

llama_cpp/llama.py

@@ -2565,16 +2565,16 @@ def longest_token_prefix(current_ids: Sequence[int], new_tokens: Sequence[int])
         if not current_ids or not new_tokens:
             return 0
 
-        # Probe inspection: Use Python to quickly compare the first token
-        # If the tokens are different from the beginning, return immediately to avoid any NumPy overhead.
-        if current_ids[0] != new_tokens[0]:
-            return 0
-
         # Determine the comparison range (limited by the shorter sequence)
         min_len = min(len(current_ids), len(new_tokens))
         if min_len == 0:
             return 0
 
+        # Probe inspection: Use Python to quickly compare the first token
+        # If the tokens are different from the beginning, return immediately to avoid any NumPy overhead.
+        if current_ids[0] != new_tokens[0]:
+            return 0
+
         # Accelerating SIMD for Large Data Volumes
         # Only transform necessary slices, avoid processing irrelevant data
         # Use asarray to ensure zero-copy (if the input is already an array)