Another ugly inlining hack, expanding the two PyDict_GetItem() calls
in LOAD_GLOBAL. Besides saving a C function call, it saves checks
whether f_globals and f_builtins are dicts, and extracting and testing
the string object's hash code is done only once. We bail out of the
inlining if the name is not exactly a string, or when its hash is -1;
because of interning, neither should ever happen. I believe interning
guarantees that the hash code is set, and I believe that the 'names'
tuple of a code object always contains interned strings, but I'm not
assuming that -- I'm simply testing hash != -1.
On my home machine, this makes a pystone variant with new-style
classes and slots run at the same speed as classic pystone! (With
new-style classes but without slots, it is still a lot slower.)
diff --git a/Python/ceval.c b/Python/ceval.c
index 4f24bab..af9c072 100644
--- a/Python/ceval.c
+++ b/Python/ceval.c
@@ -1709,13 +1709,37 @@
case LOAD_GLOBAL:
w = GETITEM(names, oparg);
+ if (PyString_CheckExact(w)) {
+ long hash = ((PyStringObject *)w)->ob_shash;
+ if (hash != -1) {
+ /* Inline the PyDict_GetItem() calls */
+ PyDictObject *d;
+ d = (PyDictObject *)(f->f_globals);
+ x = d->ma_lookup(d, w, hash)->me_value;
+ if (x != NULL) {
+ Py_INCREF(x);
+ PUSH(x);
+ continue;
+ }
+ d = (PyDictObject *)(f->f_builtins);
+ x = d->ma_lookup(d, w, hash)->me_value;
+ if (x != NULL) {
+ Py_INCREF(x);
+ PUSH(x);
+ continue;
+ }
+ goto load_global_error;
+ }
+ }
+ /* This is the un-inlined version of the code above */
x = PyDict_GetItem(f->f_globals, w);
if (x == NULL) {
x = PyDict_GetItem(f->f_builtins, w);
if (x == NULL) {
+ load_global_error:
format_exc_check_arg(
PyExc_NameError,
- GLOBAL_NAME_ERROR_MSG ,w);
+ GLOBAL_NAME_ERROR_MSG, w);
break;
}
}
