138 	int *group;		/* group to which a column belongs */  member
139 	int *cnt;		/* number of columns in the group */
140 	int *rowgroup;		/* group to which a constraint belongs */
144  * each column initially belongs to its own group and the groups
155 	g->group = isl_alloc_array(H->ctx, int, H->n_col);  in init_groups()
159 	if (!g->pos || !g->group || !g->cnt || !g->rowgroup)  in init_groups()
171 		g->group[i] = i;  in init_groups()
178 /* Update group[k] to the group column k belongs to.
179  * When merging two groups, only the group of the current
180  * group leader is changed.  Here we change the group of
181  * the other members to also point to the group that the
182  * old group leader now points to.
186 	int p = g->group[k];  in update_group()
188 		p = g->group[p];  in update_group()
189 	g->group[k] = p;  in update_group()
192 /* Merge group i with all groups of the subsequent columns
202 	g->rowgroup[j] = g->group[i];  in update_group_i_with_row_j()
206 		if (g->group[k] != g->group[i] &&  in update_group_i_with_row_j()
208 			isl_assert(H->ctx, g->cnt[g->group[k]] != 0, return -1);  in update_group_i_with_row_j()
209 			isl_assert(H->ctx, g->cnt[g->group[i]] != 0, return -1);  in update_group_i_with_row_j()
210 			if (g->group[i] < g->group[k]) {  in update_group_i_with_row_j()
211 				g->cnt[g->group[i]] += g->cnt[g->group[k]];  in update_group_i_with_row_j()
212 				g->cnt[g->group[k]] = 0;  in update_group_i_with_row_j()
213 				g->group[g->group[k]] = g->group[i];  in update_group_i_with_row_j()
215 				g->cnt[g->group[k]] += g->cnt[g->group[i]];  in update_group_i_with_row_j()
216 				g->cnt[g->group[i]] = 0;  in update_group_i_with_row_j()
217 				g->group[g->group[i]] = g->group[k];  in update_group_i_with_row_j()
225 /* Update the group information based on the constraint matrix.
256 	free(g->group);  in clear_groups()
311 		int group = g.group[done];  in isl_basic_set_factorizer()  local
312 		for (i = 1; i < g.cnt[group]; ++i) {  in isl_basic_set_factorizer()
313 			if (g.group[done + i] == group)  in isl_basic_set_factorizer()
315 			for (j = done + g.cnt[group]; j < nvar; ++j)  in isl_basic_set_factorizer()
316 				if (g.group[j] == group)  in isl_basic_set_factorizer()
321 			g.group[j] = g.group[done + i];  in isl_basic_set_factorizer()
325 		done += g.cnt[group];  in isl_basic_set_factorizer()
326 		g.pos[n++] = g.cnt[group];  in isl_basic_set_factorizer()