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authorKirill Smelkov <kirr@mns.spb.ru>2014-02-24 20:21:39 +0400
committerJunio C Hamano <gitster@pobox.com>2014-03-20 15:04:31 -0700
commit5dfb2bbd8d2e2e48aa3ad6c6a8f437bbe5d2a7fb (patch)
tree79ccc58260790a12b98becf9c8f8eb3617a6d674 /tree-diff.c
parentd00e980c224d4b65972dda4474fbd9294bdb185f (diff)
downloadgit-5dfb2bbd8d2e2e48aa3ad6c6a8f437bbe5d2a7fb.tar.gz
tree-diff: don't assume compare_tree_entry() returns -1,0,1
It does, but we'll be reworking it in the next patch after it won't, and besides it is better to stick to standard strcmp/memcmp/base_name_compare/etc... convention, where comparison function returns <0, =0, >0 Regarding performance, comparing for <0, =0, >0 should be a little bit faster, than switch, because it is just 1 test-without-immediate instruction and then up to 3 conditional branches, and in switch you have up to 3 tests with immediate and up to 3 conditional branches. No worry, that update_tree_entry(t2) is duplicated for =0 and >0 - it will be good after we'll be adding support for multiparent walker and will stay that way. =0 case goes first, because it happens more often in real diffs - i.e. paths are the same. Signed-off-by: Kirill Smelkov <kirr@mns.spb.ru> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'tree-diff.c')
-rw-r--r--tree-diff.c22
1 files changed, 14 insertions, 8 deletions
diff --git a/tree-diff.c b/tree-diff.c
index 1af8219033..6a677daa7a 100644
--- a/tree-diff.c
+++ b/tree-diff.c
@@ -178,18 +178,24 @@ int diff_tree(struct tree_desc *t1, struct tree_desc *t2,
update_tree_entry(t1);
continue;
}
- switch (compare_tree_entry(t1, t2, &base, opt)) {
- case -1:
+
+ cmp = compare_tree_entry(t1, t2, &base, opt);
+
+ /* t1 = t2 */
+ if (cmp == 0) {
update_tree_entry(t1);
- continue;
- case 0:
+ update_tree_entry(t2);
+ }
+
+ /* t1 < t2 */
+ else if (cmp < 0) {
update_tree_entry(t1);
- /* Fallthrough */
- case 1:
+ }
+
+ /* t1 > t2 */
+ else {
update_tree_entry(t2);
- continue;
}
- die("git diff-tree: internal error");
}
strbuf_release(&base);