[PATCH] Speed up git-merge-base a lot

[git.git] / merge-base.c

diff --git a/merge-base.c b/merge-base.c
index 5919566..18d81d0 100644 (file)
--- a/merge-base.c
+++ b/merge-base.c
@@ -2,6 +2,22 @@
 #include "cache.h"
 #include "commit.h"
 
+#define PARENT1 1
+#define PARENT2 2
+#define UNINTERESTING 4
+
+static int interesting(struct commit_list *list)
+{
+       while (list) {
+               struct commit *commit = list->item;
+               list = list->next;
+               if (commit->object.flags & UNINTERESTING)
+                       continue;
+               return 1;
+       }
+       return 0;
+}
+
 static struct commit *common_ancestor(struct commit *rev1, struct commit *rev2)
 {
        struct commit_list *list = NULL;
@@ -18,19 +34,18 @@ static struct commit *common_ancestor(struct commit *rev1, struct commit *rev2)
        insert_by_date(rev1, &list);
        insert_by_date(rev2, &list);
 
-       while (list) {
+       while (interesting(list)) {
                struct commit *commit = list->item;
                struct commit_list *tmp = list, *parents;
-               int flags = commit->object.flags & 3;
+               int flags = commit->object.flags & 7;
 
                list = list->next;
                free(tmp);
-               switch (flags) {
-               case 3:
+               if (flags == 3) {
                        insert_by_date(commit, &result);
-                       continue;
-               case 0:
-                       die("git-merge-base: commit without either parent?");
+
+                       /* Mark children of a found merge uninteresting */
+                       flags |= UNINTERESTING;
                }
                parents = commit->parents;
                while (parents) {