commit-reach: move min_generation check into paint_queue_get()

Consolidate the min_generation termination condition into
paint_queue_get(), alongside the existing stale-entry and
side-exhaustion checks.

Move last_gen into struct paint_state so that
commit_graph_generation() is called exactly once per dequeued commit
and the result is shared across all termination checks and the
monotonicity BUG assertion.

Signed-off-by: Kristofer Karlsson <krka@spotify.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/commit-reach.c b/commit-reach.c
index 1b445399e9bfe51d6e987f45ee4c2a913b7332d4..ba0b767b6452ec92b02cbcf167f2554f7208b988 100644 (file)
--- a/commit-reach.c
+++ b/commit-reach.c
@@ -90,6 +90,8 @@ struct paint_state {
        size_t parent2_count;
        size_t mb_candidate_count;
        int gen_ordered;
+       timestamp_t min_generation;
+       timestamp_t last_gen;
 };
 
 static void paint_count_update(struct paint_state *state,
@@ -139,11 +141,23 @@ static void paint_queue_put(struct paint_state *state,
 static struct commit *paint_queue_get(struct paint_state *state)
 {
        struct commit *commit = prio_queue_get(&state->queue);
+       timestamp_t generation;
 
        if (!commit)
                return NULL;
 
        commit->object.flags &= ~ENQUEUED;
+       generation = commit_graph_generation(commit);
+
+       if (state->min_generation && generation > state->last_gen)
+               BUG("bad generation skip %"PRItime" > %"PRItime" at %s",
+                   generation, state->last_gen,
+                   oid_to_hex(&commit->object.oid));
+       state->last_gen = generation;
+
+       /* generation cutoff */
+       if (generation < state->min_generation)
+               return NULL;
 
        if (!state->mb_candidate_count) {
                /* only stale entries remain */
@@ -153,7 +167,7 @@ static struct commit *paint_queue_get(struct paint_state *state)
                /* one side is exhausted */
                if ((!state->parent1_count || !state->parent2_count) &&
                    state->gen_ordered &&
-                   commit_graph_generation(commit) < GENERATION_NUMBER_INFINITY)
+                   generation < GENERATION_NUMBER_INFINITY)
                        return NULL;
        }
 
@@ -180,9 +194,10 @@ static int paint_down_to_common(struct repository *r,
        struct commit *commit;
        int i;
        int steps = 0;
-       timestamp_t last_gen = GENERATION_NUMBER_INFINITY;
        struct commit_list **tail = result;
 
+       state.min_generation = min_generation;
+       state.last_gen = GENERATION_NUMBER_INFINITY;
        if (!min_generation && !corrected_commit_dates_enabled(r)) {
                state.queue.compare = compare_commits_by_commit_date;
                state.gen_ordered = 0;
@@ -201,18 +216,8 @@ static int paint_down_to_common(struct repository *r,
        while ((commit = paint_queue_get(&state))) {
                struct commit_list *parents;
                int flags;
-               timestamp_t generation = commit_graph_generation(commit);
                steps++;
 
-               if (min_generation && generation > last_gen)
-                       BUG("bad generation skip %"PRItime" > %"PRItime" at %s",
-                           generation, last_gen,
-                           oid_to_hex(&commit->object.oid));
-               last_gen = generation;
-
-               if (generation < min_generation)
-                       break;
-
                flags = commit->object.flags & (PARENT1 | PARENT2 | STALE);
                if (flags == (PARENT1 | PARENT2)) {
                        if (!(commit->object.flags & RESULT)) {
@@ -225,7 +230,7 @@ static int paint_down_to_common(struct repository *r,
                                 */
                                if (!(mb_flags & MERGE_BASE_FIND_ALL) &&
                                    state.gen_ordered &&
-                                   generation < GENERATION_NUMBER_INFINITY)
+                                   state.last_gen < GENERATION_NUMBER_INFINITY)
                                        break;
                        }
                        /* Mark parents of a found merge stale */