RI HFX: Fix stack overflow

by reducing recursion depth of `neighbor_list_3c_iterate`

Stack size of regtest `H2O-hfx-periodic-ri-truncated.inp` was exceeding
8MB (now less than 0.3MB)

src/hfx_ri.F

@@ -378,9 +378,10 @@ SUBROUTINE hfx_ri_pre_scf_calc_tensors(qs_env, ri_data, t_2c_int_RI, t_2c_int_po
          CALL init_interaction_radii_orb_basis(orb_basis, ri_data%eps_pgf_orb)
       ENDDO
 
-      n_mem = ri_data%n_mem
-      CALL create_tensor_batches(sizes_AO, n_mem, starts_array_mc_int, ends_array_mc_int, &
+      CALL create_tensor_batches(sizes_AO, ri_data%n_mem, starts_array_mc_int, ends_array_mc_int, &
                                  starts_array_mc_block_int, ends_array_mc_block_int)
+
+      n_mem = ri_data%n_mem
       DEALLOCATE (starts_array_mc_int, ends_array_mc_int)
 
       CALL create_3c_tensor(t_3c_int_batched(1, 1), dist_RI, dist_AO_1, dist_AO_2, ri_data%pgrid, &

src/qs_tensors.F

@@ -462,6 +462,19 @@ RECURSIVE FUNCTION neighbor_list_3c_iterate(iterator) RESULT(iter_stat)
          IF (iter_stat /= 0) THEN
             RETURN
          ENDIF
+
+         CALL get_iterator_info(iterator%iter_ij, iatom=iatom, jatom=jatom)
+         skip_this = .FALSE.
+         IF ((iterator%bounds_i(1) > 0 .AND. iatom < iterator%bounds_i(1)) &
+             .OR. (iterator%bounds_i(2) > 0 .AND. iatom > iterator%bounds_i(2))) skip_this = .TRUE.
+         IF ((iterator%bounds_j(1) > 0 .AND. jatom < iterator%bounds_j(1)) &
+             .OR. (iterator%bounds_j(2) > 0 .AND. jatom > iterator%bounds_j(2))) skip_this = .TRUE.
+
+         IF (skip_this) THEN
+            iter_stat = neighbor_list_3c_iterate(iterator)
+            RETURN
+         ENDIF
+
       ENDIF
       iter_stat = nl_sub_iterate(iterator%iter_jk, iterator%iter_ij)
       IF (iter_stat /= 0) THEN
@@ -481,10 +494,6 @@ RECURSIVE FUNCTION neighbor_list_3c_iterate(iterator) RESULT(iter_stat)
       jatom = jatom_1
 
       skip_this = .FALSE.
-      IF ((iterator%bounds_i(1) > 0 .AND. iatom < iterator%bounds_i(1)) &
-          .OR. (iterator%bounds_i(2) > 0 .AND. iatom > iterator%bounds_i(2))) skip_this = .TRUE.
-      IF ((iterator%bounds_j(1) > 0 .AND. jatom < iterator%bounds_j(1)) &
-          .OR. (iterator%bounds_j(2) > 0 .AND. jatom > iterator%bounds_j(2))) skip_this = .TRUE.
       IF ((iterator%bounds_k(1) > 0 .AND. katom < iterator%bounds_k(1)) &
           .OR. (iterator%bounds_k(2) > 0 .AND. katom > iterator%bounds_k(2))) skip_this = .TRUE.