PERF: allow slice indexers to be computed faster

Author: jreback

pandas/tseries/index.py

@@ -1376,7 +1376,10 @@ def __getitem__(self, key):
         else:
             if com._is_bool_indexer(key):
                 key = np.asarray(key)
-                key = lib.maybe_booleans_to_slice(key.view(np.uint8))
+                if key.all():
+                    key = slice(0,None,None)
+                else:
+                    key = lib.maybe_booleans_to_slice(key.view(np.uint8))
 
             new_offset = None
             if isinstance(key, slice):