[PATCH 7/7] tree-diff.c: Avoid recomputing interesting-ness for subtrees when possible
- From
Elijah Newren <newren@gmail.com>
- Date
- Aug 25, 2010, 02:53 UTC
- Message-ID
- <1282704795-29661-8-git-send-email-newren@gmail.com>
- In-Reply-To
- <1282704795-29661-1-git-send-email-newren@gmail.com>
Weather balloon patch. Doesn't seem to help much in benchmarks, and after many runs I think it might occasionally hurt slightly. It ought to help in the case of a ginormous tree that is really deep with few entries per tree, but that case seems kind of contrived.
Kind of makes the code look icky too.
--- No signed-off-by, since I'm not sold on this patch and am somewhat leaning against it. It would need a better commit message anyway. :-)
tree-diff.c | 29 +++++++++++++++-------------- 1 files changed, 15 insertions(+), 14 deletions(-)
diff --git a/tree-diff.c b/tree-diff.c index 292cb6b..3c34c77 100644 --- a/tree-diff.c +++ b/tree-diff.c @@ -25,9 +25,9 @@ static char *malloc_fullname(const char *base, int baselen, const char *path, in } static void show_entry(struct diff_options *opt, const char *prefix, struct tree_desc *desc, - const char *base, int baselen); + const char *base, int baselen, int all_interesting); -static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const char *base, int baselen, struct diff_options *opt) +static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const char *base, int baselen, struct diff_options *opt, int all_t1_interesting, int all_t2_interesting) { unsigned mode1, mode2; const char *path1, *path2; @@ -42,11 +42,11 @@ static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const pathlen2 = tree_entry_len(path2, sha2); cmp = base_name_compare(path1, pathlen1, mode1, path2, pathlen2, mode2); if (cmp < 0) { - show_entry(opt, "-", t1, base, baselen); + show_entry(opt, "-", t1, base, baselen, all_t1_interesting); return -1; } if (cmp > 0) { - show_entry(opt, "+", t2, base, baselen); + show_entry(opt, "+", t2, base, baselen, all_t2_interesting); return 1; } if (!DIFF_OPT_TST(opt, FIND_COPIES_HARDER) && !hashcmp(sha1, sha2) && mode1 == mode2) @@ -57,8 +57,8 @@ static int compare_tree_entry(struct tree_desc *t1, struct tree_desc *t2, const * file, we need to consider it a remove and an add. */ if (S_ISDIR(mode1) != S_ISDIR(mode2)) { - show_entry(opt, "-", t1, base, baselen); - show_entry(opt, "+", t2, base, baselen); + show_entry(opt, "-", t1, base, baselen, all_t1_interesting); + show_entry(opt, "+", t2, base, baselen, all_t2_interesting); return 0; } @@ -197,9 +197,8 @@ int tree_entry_interesting(struct tree_desc *desc, const char *base, int baselen } /* A whole sub-tree went away or appeared */ -static void show_tree(struct diff_options *opt, const char *prefix, struct tree_desc *desc, const char *base, int baselen) +static void show_tree(struct diff_options *opt, const char *prefix, struct tree_desc *desc, const char *base, int baselen, int all_interesting) { - int all_interesting = 0; while (desc->size) { int show; @@ -214,14 +213,14 @@ static void show_tree(struct diff_options *opt, const char *prefix, struct tree_ if (show < 0) break; if (show) - show_entry(opt, prefix, desc, base, baselen); + show_entry(opt, prefix, desc, base, baselen, all_interesting); update_tree_entry(desc); } } /* A file entry went away or appeared */ static void show_entry(struct diff_options *opt, const char *prefix, struct tree_desc *desc, - const char *base, int baselen) + const char *base, int baselen, int all_interesting) { unsigned mode; const char *path; @@ -246,7 +245,7 @@ static void show_entry(struct diff_options *opt, const char *prefix, struct tree } init_tree_desc(&inner, tree, size); - show_tree(opt, prefix, &inner, newbase, baselen + 1 + pathlen); + show_tree(opt, prefix, &inner, newbase, baselen + 1 + pathlen, all_interesting); free(tree); free(newbase); @@ -295,16 +294,18 @@ int diff_tree(struct tree_desc *t1, struct tree_desc *t2, const char *base, stru if (!t1->size) { if (!t2->size) break; - show_entry(opt, "+", t2, base, baselen); + show_entry(opt, "+", t2, base, baselen, all_t2_interesting); update_tree_entry(t2); continue; } if (!t2->size) { - show_entry(opt, "-", t1, base, baselen); + show_entry(opt, "-", t1, base, baselen, all_t1_interesting); update_tree_entry(t1); continue; } - switch (compare_tree_entry(t1, t2, base, baselen, opt)) { + switch (compare_tree_entry(t1, t2, base, baselen, opt, + all_t1_interesting, + all_t2_interesting)) { case -1: update_tree_entry(t1); continue;
-- 1.7.2.2.39.gf7e23