diff --git a/bisect.c b/bisect.c index 58bc9c73a4..d8c2c8f7a7 100644 --- a/bisect.c +++ b/bisect.c @@ -103,8 +103,10 @@ static int count_interesting_parents(struct commit *commit, unsigned bisect_flag return count; } -static inline int halfway(struct commit_list *p, int nr) +static inline int approx_halfway(struct commit_list *p, int nr) { + int diff; + /* * Don't short-cut something we are not going to return! */ @@ -113,13 +115,22 @@ static inline int halfway(struct commit_list *p, int nr) if (DEBUG_BISECT) return 0; /* - * 2 and 3 are halfway of 5. + * For small number of commits 2 and 3 are halfway of 5, and * 3 is halfway of 6 but 2 and 4 are not. */ - switch (2 * weight(p) - nr) { + diff = 2 * weight(p) - nr; + switch (diff) { case -1: case 0: case 1: return 1; default: + /* + * For large number of commits we are not so strict, it's + * good enough if it's within ~0.1% of the halfway point, + * e.g. 5000 is exactly halfway of 10000, but we consider + * the values [4996, 5004] as halfway as well. + */ + if (abs(diff) < nr / 1024) + return 1; return 0; } } @@ -321,8 +332,9 @@ static struct commit_list *do_find_bisection(struct commit_list *list, weight_set(p, count_distance(p)); clear_distance(list); - /* Does it happen to be at exactly half-way? */ - if (!(bisect_flags & FIND_BISECTION_ALL) && halfway(p, nr)) + /* Does it happen to be at half-way? */ + if (!(bisect_flags & FIND_BISECTION_ALL) && + approx_halfway(p, nr)) return p; counted++; } @@ -362,8 +374,9 @@ static struct commit_list *do_find_bisection(struct commit_list *list, else weight_set(p, weight(q)); - /* Does it happen to be at exactly half-way? */ - if (!(bisect_flags & FIND_BISECTION_ALL) && halfway(p, nr)) + /* Does it happen to be at half-way? */ + if (!(bisect_flags & FIND_BISECTION_ALL) && + approx_halfway(p, nr)) return p; } }