fix ops.max (#1993)

Author: lvyufeng

mindnlp/core/ops/reduction.py

@@ -52,9 +52,20 @@ def max(*args, **kwargs):
     if use_pyboost() and has_max:
         return mindspore.mint.max(*args, **kwargs)
 
-    input = kwargs.get('input', None) or args[0]
-    dim = kwargs.get('dim', None) or args[1]
-    keepdim = kwargs.get('keepdim', False) or args[2]
+    input = kwargs.get('input', None)
+    dim = kwargs.get('dim', None)
+    keepdim = kwargs.get('keepdim', False)
+    if len(args) == 1:
+        input = args[0]
+    elif len(args) == 2:
+        input = args[0]
+        dim = args[1]
+    elif len(args) == 3:
+        input = args[0]
+        dim = args[1]
+        keepdim = args[2]
+    else:
+        raise RuntimeError(f'need 3 inputs but got {len(args)}')
     out = ops.max(input, dim, keepdim)
     if dim is None:
         return out[0]