[PATCH] rev-list: estimate number of bisection step left
- From
Christian Couder <chriscool@tuxfamily.org>
- Date
- Feb 17, 2009, 05:09 UTC
- Message-ID
- <20090217060944.488184b0.chriscool@tuxfamily.org>
This patch teaches "git rev-list --bisect-vars" to output an estimate of the number of bisection step left along with the other variables it already outputs.
The estimate is calculated using log2(all_revisions_left/2 - 1). This is the most straightforward formula and seems to work fine in practice.
We substract 1 to "all_revisions_left/2" because we allready know one bad revision.
Signed-off-by: Christian Couder <chriscool@tuxfamily.org> --- builtin-rev-list.c | 27 +++++++++++++++++++++++++-- git-bisect.sh | 2 +- 2 files changed, 26 insertions(+), 3 deletions(-)
diff --git a/builtin-rev-list.c b/builtin-rev-list.c index 436afa4..ee4abe7 100644 --- a/builtin-rev-list.c +++ b/builtin-rev-list.c @@ -574,6 +574,27 @@ static struct commit_list *find_bisection(struct commit_list *list, return best; } +/* + * Estimate the number of bisect steps left + * Taking log2(all_revisions_left/2 - 1) seems to work fine. + * "- 1" is because we already know one bad revision. + */ +static int estimate_bisect_steps(int all) +{ + int log2 = 0; + int left = (all >> 1) - 1; + + if (left <= 0) + return 0; + + do { + left = left >> 1; + log2++; + } while (left); + + return log2; +} + int cmd_rev_list(int argc, const char **argv, const char *prefix) { struct commit_list *list; @@ -688,12 +709,14 @@ int cmd_rev_list(int argc, const char **argv, const char *prefix) "bisect_nr=%d\n" "bisect_good=%d\n" "bisect_bad=%d\n" - "bisect_all=%d\n", + "bisect_all=%d\n" + "bisect_steps=%d\n", hex, cnt - 1, all - reaches - 1, reaches - 1, - all); + all, + estimate_bisect_steps(all)); return 0; } } diff --git a/git-bisect.sh b/git-bisect.sh index 85db4ba..6b23439 100755 --- a/git-bisect.sh +++ b/git-bisect.sh @@ -500,7 +500,7 @@ bisect_next() { # commit is also a "skip" commit (see above). exit_if_skipped_commits "$bisect_rev" - bisect_checkout "$bisect_rev" "$bisect_nr revisions left to test after this" + bisect_checkout "$bisect_rev" "$bisect_nr revisions left to test after this (roughtly $bisect_steps steps)" } bisect_visualize() {
-- 1.6.2.rc0.90.g0753.dirty