#define NO_THE_INDEX_COMPATIBILITY_MACROS
#include "cache.h"
+#include "config.h"
#include "dir.h"
#include "tree.h"
#include "tree-walk.h"
return ret;
}
+static inline int are_same_oid(struct name_entry *name_j, struct name_entry *name_k)
+{
+ return name_j->oid && name_k->oid && !oidcmp(name_j->oid, name_k->oid);
+}
+
static int traverse_trees_recursive(int n, unsigned long dirmask,
unsigned long df_conflicts,
struct name_entry *names,
struct traverse_info *info)
{
int i, ret, bottom;
+ int nr_buf = 0;
struct tree_desc t[MAX_UNPACK_TREES];
void *buf[MAX_UNPACK_TREES];
struct traverse_info newinfo;
newinfo.pathlen += tree_entry_len(p) + 1;
newinfo.df_conflicts |= df_conflicts;
+ /*
+ * Fetch the tree from the ODB for each peer directory in the
+ * n commits.
+ *
+ * For 2- and 3-way traversals, we try to avoid hitting the
+ * ODB twice for the same OID. This should yield a nice speed
+ * up in checkouts and merges when the commits are similar.
+ *
+ * We don't bother doing the full O(n^2) search for larger n,
+ * because wider traversals don't happen that often and we
+ * avoid the search setup.
+ *
+ * When 2 peer OIDs are the same, we just copy the tree
+ * descriptor data. This implicitly borrows the buffer
+ * data from the earlier cell.
+ */
for (i = 0; i < n; i++, dirmask >>= 1) {
- const unsigned char *sha1 = NULL;
- if (dirmask & 1)
- sha1 = names[i].oid->hash;
- buf[i] = fill_tree_descriptor(t+i, sha1);
+ if (i > 0 && are_same_oid(&names[i], &names[i - 1]))
+ t[i] = t[i - 1];
+ else if (i > 1 && are_same_oid(&names[i], &names[i - 2]))
+ t[i] = t[i - 2];
+ else {
+ const unsigned char *sha1 = NULL;
+ if (dirmask & 1)
+ sha1 = names[i].oid->hash;
+ buf[nr_buf++] = fill_tree_descriptor(t+i, sha1);
+ }
}
bottom = switch_cache_bottom(&newinfo);
ret = traverse_trees(n, t, &newinfo);
restore_cache_bottom(&newinfo, bottom);
- for (i = 0; i < n; i++)
+ for (i = 0; i < nr_buf; i++)
free(buf[i]);
return ret;