fix detection of duplicate tensors

bindings/python/py_src/safetensors/torch.py

@@ -41,6 +41,10 @@ def storage_size(tensor: torch.Tensor) -> int:
             return tensor.nelement() * _SIZE[tensor.dtype]
 
 
+def storage_offset(tensor: torch.Tensor) -> int:
+    return tensor.storage_offset()
+
+
 def _filter_shared_not_shared(tensors: List[Set[str]], state_dict: Dict[str, torch.Tensor]) -> List[Set[str]]:
     filtered_tensors = []
     for shared in tensors:
@@ -71,7 +75,8 @@ def _find_shared_tensors(state_dict: Dict[str, torch.Tensor]) -> List[Set[str]]:
     for k, v in state_dict.items():
         if v.device != torch.device("meta") and storage_ptr(v) != 0 and storage_size(v) != 0:
             # Need to add device as key because of multiple GPU.
-            tensors[(v.device, storage_ptr(v), storage_size(v))].add(k)
+            # Need to add storage_offset as key because views may share the same data_ptr.
+            tensors[(v.device, storage_ptr(v), storage_size(v), storage_offset(v))].add(k)
     tensors = list(sorted(tensors.values()))
     tensors = _filter_shared_not_shared(tensors, state_dict)
     return tensors