partial optimisation for ord(Py_UNICODE) - better optimisation that returns a...

partial optimisation for ord(Py_UNICODE) - better optimisation that returns a C integer result requires type analysis refactoring

Cython/Compiler/Optimize.py

@@ -1939,6 +1939,17 @@ class OptimizeBuiltinCalls(Visitor.EnvTransform):
             test_node = UtilNodes.EvalWithTempExprNode(temp, test_node)
         return test_node
 
+    def _handle_simple_function_ord(self, node, pos_args):
+        """Unpack ord(Py_UNICODE).
+        """
+        if len(pos_args) != 1:
+            return node
+        arg = pos_args[0]
+        if isinstance(arg, ExprNodes.CoerceToPyTypeNode):
+            if arg.arg.type is PyrexTypes.c_py_unicode_type:
+                return arg.arg.coerce_to(node.type, self.current_env())
+        return node
+
     ### special methods
 
     Pyx_tp_new_func_type = PyrexTypes.CFuncType(

tests/run/builtin_ord.pyx

+
+cimport cython
+
+ustring_with_a = u'abcdefg'
+ustring_without_a = u'bcdefg'
+
+@cython.test_fail_if_path_exists('//SimpleCallNode')
+def unicode_for_loop_ord(unicode s):
+    """
+    >>> unicode_for_loop_ord(ustring_with_a)
+    True
+    >>> unicode_for_loop_ord(ustring_without_a)
+    False
+    """
+    for c in s:
+        if ord(c) == u'a':
+            return True
+    return False