Skip pipeline if target == 0

1 files changed, 26 insertions, 14 deletions

diff --git a/src/solvers/h48/solve.h b/src/solvers/h48/solve.h
index 2abc4c9..830a6b2 100644
--- a/src/solvers/h48/solve.h
+++ b/src/solvers/h48/solve.h
@@ -285,36 +285,48 @@ solve_h48_dfs(dfsarg_solve_h48_t arg[static 1])
         uint8_t m, nm, nn, ni, target;
         uint64_t mm_normal, mm_inverse;
         bool normal;
-        cube_t backup_cube, backup_inverse;
+        cube_t cube, backup_cube, backup_inverse;
         h48_prune_t prune[NMOVES];
 
         nn = arg->solution_moves->nmoves;
         ni = arg->solution_moves->npremoves;
         nm = nn + ni;
-        if (equal(arg->cube, SOLVED_CUBE)) {
-                if (arg->target_depth != nm)
-                        return 0;
-                wrapthread_mutex_lock(arg->solutions_mutex);
-                ret = appendsolution(arg->solution_moves, H48_STARTING_MOVES,
-                    arg->tmask, arg->solution_settings, arg->solution_list);
-                wrapthread_mutex_unlock(arg->solutions_mutex);
-                return ret;
-        }
 
-        if (nm + 1 > arg->target_depth ||
+        if (equal(arg->cube, SOLVED_CUBE) || /* Solved before target depth */
             arg->solution_list->nsols >= arg->solution_settings->maxsolutions)
                 return 0;
 
-        ret = 0;
         target = arg->target_depth - (nm + 1);
-        backup_cube = arg->cube;
-        backup_inverse = arg->inverse;
         mm_normal = arg->movemask_normal;
         mm_inverse = arg->movemask_inverse;
+        if (target == 0) { /* Last move */
+                arg->solution_moves->nmoves++;
+                for (m = 0; m < NMOVES; m++) {
+                        if (!(mm_normal & mm_inverse & MM_SINGLE(m)))
+                                continue;
+                        cube = move(arg->cube, m);
+                        arg->solution_moves->moves[nn] = m;
+                        if (!equal(cube, SOLVED_CUBE))
+                                continue;
+                        wrapthread_mutex_lock(arg->solutions_mutex);
+                        ret = appendsolution(arg->solution_moves,
+                            H48_STARTING_MOVES, arg->tmask,
+                            arg->solution_settings, arg->solution_list);
+                        wrapthread_mutex_unlock(arg->solutions_mutex);
+                        arg->solution_moves->nmoves--;
+                        return ret;
+                }
+                arg->solution_moves->nmoves--;
+                return 0;
+        }
+
+        backup_cube = arg->cube;
+        backup_inverse = arg->inverse;
         normal = popcount_u32(mm_normal) <= popcount_u32(mm_inverse);
 
         h48_prune_pipeline(arg, prune, target, normal);
 
+        ret = 0;
         if (normal) {
                 arg->solution_moves->nmoves++;
                 for (m = 0; m < NMOVES; m++) {