diff --git a/jedi/evaluate/filters.py b/jedi/evaluate/filters.py
index 5db0c95a..70fa03a7 100644
--- a/jedi/evaluate/filters.py
+++ b/jedi/evaluate/filters.py
@@ -11,6 +11,7 @@ from jedi.evaluate import flow_analysis
 from jedi.evaluate.base_context import ContextSet, Context
 from jedi.parser_utils import get_parent_scope
 from jedi.evaluate.utils import to_list
+from jedi.evaluate.cache import evaluator_function_cache
 
 
 class AbstractNameDefinition(object):
@@ -188,28 +189,44 @@ class NameWrapper(object):
         return '%s(%s)' % (self.__class__.__name__, self._wrapped_name)
 
 
+@evaluator_function_cache()
+def _get_definition_names(evaluator, module_node, name_key):
+    try:
+        names = module_node.get_used_names()[name_key]
+    except KeyError:
+        return []
+    return [name for name in names if name.is_definition()]
+
+
 class AbstractUsedNamesFilter(AbstractFilter):
     name_class = TreeNameDefinition
 
     def __init__(self, context, parser_scope):
         self._parser_scope = parser_scope
-        self._used_names = self._parser_scope.get_root_node().get_used_names()
+        self._module_node = self._parser_scope.get_root_node()
+        self._used_names = self._module_node.get_used_names()
         self.context = context
 
     def get(self, name):
-        try:
-            names = self._used_names[name]
-        except KeyError:
-            return []
-
-        return self._convert_names(self._filter(names))
+        #print(self, self.context, name, type(self).__name__)
+        #import traceback, sys; traceback.print_stack(file=sys.stdout)
+        return self._convert_names(self._filter(
+            _get_definition_names(self.context.evaluator, self._module_node, name)
+        ))
 
     def _convert_names(self, names):
         return [self.name_class(self.context, name) for name in names]
 
     def values(self):
-        return self._convert_names(name for name_list in self._used_names.values()
-                                   for name in self._filter(name_list))
+        evaluator = self.context.evaluator
+        module_node = self._module_node
+        return self._convert_names(
+            name
+            for name_key in self._used_names
+            for name in self._filter(
+                _get_definition_names(evaluator, module_node, name_key)
+            )
+        )
 
     def __repr__(self):
         return '<%s: %s>' % (self.__class__.__name__, self.context)
@@ -238,8 +255,6 @@ class ParserTreeFilter(AbstractUsedNamesFilter):
         return list(self._check_flows(names))
 
     def _is_name_reachable(self, name):
-        if not name.is_definition():
-            return False
         parent = name.parent
         if parent.type == 'trailer':
             return False
@@ -288,12 +303,25 @@ class GlobalNameFilter(AbstractUsedNamesFilter):
     def __init__(self, context, parser_scope):
         super(GlobalNameFilter, self).__init__(context, parser_scope)
 
+    def get(self, name):
+        try:
+            names = self._used_names[name]
+        except KeyError:
+            return []
+        return self._convert_names(self._filter(names))
+
     @to_list
     def _filter(self, names):
         for name in names:
             if name.parent.type == 'global_stmt':
                 yield name
 
+    def values(self):
+        return self._convert_names(
+            name for name_list in self._used_names.values()
+            for name in self._filter(name_list)
+        )
+
 
 class DictFilter(AbstractFilter):
     def __init__(self, dct):