-/**
- * Generates constraints which interrelate x with y variables.
- * x1 and x2 have the different colors ==> y_12 = 1
- */
-static void pi_add_constr_E(problem_instance_t *pi) {
- unit_t *curr;
- bitset_t *root_regs, *arg_regs, *work_regs;
- int cst_counter = 0;
- unsigned nregs = pi->co->chordal_env->cls->n_regs;
- root_regs = bitset_alloca(nregs);
- arg_regs = bitset_alloca(nregs);
- work_regs = bitset_alloca(nregs);
-
- DBG((dbg, LEVEL_2, "Add E constraints...\n"));
- /* for all roots of optimization units */
- list_for_each_entry(unit_t, curr, &pi->co->units, units) {
- ir_node *root, *arg;
- int rootnr, argnr, color;
- int y_idx, i;
- char buf[32];
-
- root = curr->nodes[0];
- rootnr = get_irn_graph_nr(root);
- bitset_clear_all(root_regs);
- arch_get_allocatable_regs(get_arch_env(pi->co), root, -1, pi->co->chordal_env->cls, root_regs);
-
- /* for all arguments of root */
- for (i = 1; i < curr->node_count; ++i) {
- arg = curr->nodes[i];
- argnr = get_irn_graph_nr(arg);
- bitset_clear_all(arg_regs);
- arch_get_allocatable_regs(get_arch_env(pi->co), arg, -1, pi->co->chordal_env->cls, arg_regs);
-
- /* Introduce new variable and set factor in objective function */
- mangle_var2(buf, 'y', rootnr, argnr);
- y_idx = lpp_add_var(pi->curr_lp, buf, lpp_binary, curr->costs[i]);
-
- /* set starting value */
- lpp_set_start_value(pi->curr_lp, y_idx, (get_irn_col(pi->co, root) != get_irn_col(pi->co, arg)));
-
- /* For all colors root and arg have in common, add 2 constraints to E */
- bitset_copy(work_regs, root_regs);
- bitset_and(work_regs, arg_regs);
- bitset_foreach(work_regs, color) {
- int root_idx, arg_idx, cst_idx;
- mangle_var2(buf, 'x', rootnr, color);
- root_idx = lpp_get_var_idx(pi->curr_lp, buf);
- mangle_var2(buf, 'x', argnr, color);
- arg_idx = lpp_get_var_idx(pi->curr_lp, buf);
-
- /* add root-arg-y <= 0 */
- mangle_cst(buf, 'E', cst_counter++);
- cst_idx = lpp_add_cst(pi->curr_lp, buf, lpp_less, 0);
- lpp_set_factor_fast(pi->curr_lp, cst_idx, root_idx, 1);
- lpp_set_factor_fast(pi->curr_lp, cst_idx, arg_idx, -1);
- lpp_set_factor_fast(pi->curr_lp, cst_idx, y_idx, -1);
-
- /* add arg-root-y <= 0 */
- mangle_cst(buf, 'E', cst_counter++);
- cst_idx = lpp_add_cst(pi->curr_lp, buf, lpp_less, 0);
- lpp_set_factor_fast(pi->curr_lp, cst_idx, root_idx, -1);
- lpp_set_factor_fast(pi->curr_lp, cst_idx, arg_idx, 1);
- lpp_set_factor_fast(pi->curr_lp, cst_idx, y_idx, -1);
- }
- /* For all colors root and arg have "disjunct", add 1 constraints to E.
- * If root gets a color the arg is not possible to get then they will
- * definetly get different colors. So y has to be 1.
- * Vice versa for arg.
- */
- bitset_copy(work_regs, root_regs);
- bitset_xor(work_regs, arg_regs);
- bitset_foreach(work_regs, color) {
- int root_idx, arg_idx, cst_idx;
- mangle_var2(buf, 'x', rootnr, color);
- root_idx = lpp_get_var_idx(pi->curr_lp, buf);
- mangle_var2(buf, 'x', argnr, color);
- arg_idx = lpp_get_var_idx(pi->curr_lp, buf);
-
- mangle_cst(buf, 'E', cst_counter++);
- cst_idx = lpp_add_cst(pi->curr_lp, buf, lpp_less, 0);
- if (bitset_is_set(root_regs, color)) {
- /* add root-y <= 0 */
- lpp_set_factor_fast(pi->curr_lp, cst_idx, root_idx, 1);
- lpp_set_factor_fast(pi->curr_lp, cst_idx, y_idx, -1);
- } else {
- assert(bitset_is_set(arg_regs, color) && "bitset_xor is buggy");
- /* add arg-y <= 0 */
- lpp_set_factor_fast(pi->curr_lp, cst_idx, arg_idx, 1);
- lpp_set_factor_fast(pi->curr_lp, cst_idx, y_idx, -1);
- }
- }
- }
- }
-}
-
-static INLINE int get_costs(problem_instance_t *pi, ir_node *phi, ir_node *irn) {
- int i;
- unit_t *curr;
- /* search optimization unit for phi */
- list_for_each_entry(unit_t, curr, &pi->co->units, units)
- if (curr->nodes[0] == phi) {
- for (i=1; i<curr->node_count; ++i)
- if (curr->nodes[i] == irn)
- return curr->costs[i];
- assert(0 && "irn must occur in this ou");
- }
- assert(0 && "phi must be found in a ou");
- return 0;
-}
-
-static void clique_path_walker(ir_node *block, void *env) {
- problem_instance_t *pi = env;
- int count, arity, row, col, other_row, *costs;
- ir_node **phis, *phi, *irn, **phi_matrix;
- pset *done;
- bitset_t *candidates;
-
- /* Count all phi nodes of this block */
- for (count=0, irn = sched_first(block); is_Phi(irn); irn = sched_next(irn))
- count++;
-
- /* We at least 2 phi nodes for this class of inequalities */
- if (count < 2)
- return;
-
- /* Build the \Phi-Matrix */
- arity = get_irn_arity(sched_first(block));
- phis = alloca(count * sizeof(*phis));
- costs = alloca(count * sizeof(costs));
- phi_matrix = alloca(count*arity * sizeof(*phi_matrix));
- candidates = bitset_alloca(count);
-
- phi = sched_first(block);
- for (row=0; row<count; ++row) {
- phis[row] = phi;
- for (col=0; col<arity; ++col) {
- ir_node *arg = get_irn_n(phi, col);
- /* Sort out all arguments interfering with its phi */
- if (nodes_interfere(pi->co->chordal_env, phi, arg)) {
- phi_matrix[row*arity + col] = NULL;
- } else
- phi_matrix[row*arity + col] = arg;
- }
- phi = sched_next(phi);
- }
-
- /* Now find the interesting patterns in the matrix:
- * All nodes which are used at least twice in a column. */
- /* columnwise ... */
- for (col=0; col<arity; ++col) {
- done = pset_new_ptr_default();
- for (row=0; row<count; ++row) {
- irn = phi_matrix[row*arity + col];
- /*
- * is this an interfering arg (NULL)
- * or has the irn already been processed in this col?
- */
- if (!irn || pset_find_ptr(done, irn))
- continue;
- else
- pset_insert_ptr(done, irn);
-
- /* insert irn in candidates */
- bitset_clear_all(candidates);
- bitset_set(candidates, row);
- /* search the irn in the rows below */
- for (other_row = row+1; other_row<count; ++other_row)
- if (irn == phi_matrix[other_row*arity + col]) {
- /* found the irn in the same col in another row */
- bitset_set(candidates, other_row);
- }
-
- /* now we know all occurences of irn in this col */
- if (bitset_popcnt(candidates) < 2)
- continue;
-
- /* generate an unequation finally.
- * phis are indexed in the bitset,
- * shared argument is irn
- * rhs is phi_count - 1 */
- {
- char buf[32];
- ir_node *root;
- int pos, irnnr, rootnr, cst_idx, y_idx, cst_counter = 0;
- int minimal_unequal_count = bitset_popcnt(candidates)-1;
-
- irnnr = get_irn_graph_nr(irn);
- mangle_cst(buf, 'M', cst_counter++);
- cst_idx = lpp_add_cst(pi->curr_lp, buf, lpp_greater, minimal_unequal_count);
-
- /* for all phis */
- bitset_foreach(candidates, pos) {
- root = phis[pos];
- rootnr = get_irn_graph_nr(root);
- mangle_var2(buf, 'y', rootnr, irnnr);
- y_idx = lpp_get_var_idx(pi->curr_lp, buf);
- lpp_set_factor_fast(pi->curr_lp, cst_idx, y_idx, 1);
- }
- }
- }
- del_pset(done); /* clear set for next row */
- } /*next col*/
-}