[pypy-commit] stmgc c8-hashtable: major gc: remove from 'modified_old_objects' all old hashtables that die

[arigo]

Author: Armin Rigo <arigo at tunes.org>
Branch: c8-hashtable
Changeset: r1727:591a48b66365
Date: 2015-03-12 16:29 +0100
http://bitbucket.org/pypy/stmgc/changeset/591a48b66365/

Log:	major gc: remove from 'modified_old_objects' all old hashtables that
	die

diff --git a/c8/stm/gcpage.c b/c8/stm/gcpage.c
--- a/c8/stm/gcpage.c
+++ b/c8/stm/gcpage.c
@@ -460,8 +460,8 @@
         struct stm_undo_s *modified = (struct stm_undo_s *)lst->items;
         struct stm_undo_s *end = (struct stm_undo_s *)(lst->items + lst->count);
         for (; modified < end; modified++) {
-            /* this logic also works if type2 == TYPE_MODIFIED_HASHTABLE */
-            if (modified->type == TYPE_POSITION_MARKER)
+            if (modified->type == TYPE_POSITION_MARKER &&
+                    modified->type2 != TYPE_MODIFIED_HASHTABLE)
                 mark_visit_possibly_new_object(modified->marker_object, pseg);
         }
     }
@@ -594,6 +594,31 @@
                 list_set_item(lst, n, list_pop_item(lst));
             }
         }
+
+        /* Remove from 'modified_old_objects' all old hashtables that die */
+        {
+            lst = pseg->modified_old_objects;
+            uintptr_t j, k = 0, limit = list_count(lst);
+            for (j = 0; j < limit; j += 3) {
+                uintptr_t e0 = list_item(lst, j + 0);
+                uintptr_t e1 = list_item(lst, j + 1);
+                uintptr_t e2 = list_item(lst, j + 2);
+                if (e0 == TYPE_POSITION_MARKER &&
+                    e1 == TYPE_MODIFIED_HASHTABLE &&
+                    !mark_visited_test((object_t *)e2)) {
+                    /* hashtable object dies */
+                }
+                else {
+                    if (j != k) {
+                        list_set_item(lst, k + 0, e0);
+                        list_set_item(lst, k + 1, e1);
+                        list_set_item(lst, k + 2, e2);
+                    }
+                    k += 3;
+                }
+            }
+            lst->count = k;
+        }
     }
 #pragma pop_macro("STM_SEGMENT")
 #pragma pop_macro("STM_PSEGMENT")