- /*
- * Check, if this block has already been processed, if true, return
- * immediately.
- */
- if(bitset_is_set(env->processed, block_nr))
- return;
-
- /*
- * Ensure, that the immediate dominator of this block is allocated
- * before this block, since the values live in at this block are
- * defined in the dominators of this block. Coloring the dominators
- * thus is vital before coloring this block.
- */
- if(idom)
- block_alloc(idom, env);
-
- /* Clear the live and allocate the color bitset. */
- bitset_clear_all(live);
- bitset_clear_all(colors);
- bitset_clear_all(in_colors);
-
- INIT_LIST_HEAD(&head);
-
- /*
- * Make final uses of all values live out of the block.
- * They are neccessary to build up real intervals.
- */
- for(irn = pset_first(live_end); irn; irn = pset_next(live_end)) {
- DBG((dbg, LEVEL_3, "Making live: %n/%d\n", irn, get_irn_graph_nr(irn)));
- bitset_set(live, get_irn_graph_nr(irn));
- if(!is_Phi(irn) && is_allocatable_irn(irn))
- border_add(env, &head, irn, step, 0);
- }
-
- ++step;
-
- /*
- * Determine the last uses of a value inside the block, since they are
- * relevant for the interval borders.
- */
- sched_foreach_reverse(block, irn) {
- DBG((dbg, LEVEL_1, "insn: %n\n", irn));
- DBG((dbg, LEVEL_2, "live: %b\n", live));
-
- set_irn_color(irn, NO_COLOR);
-
- /*
- * If the node defines a datab value, i.e. something, registers must
- * be allocated for, add a new def border to the border list.
- */
- if(is_allocatable_irn(irn)) {
- int nr = get_irn_graph_nr(irn);
-
- bitset_clear(live, nr);
- border_add(env, &head, irn, step, 1);
-
-#ifdef BUILD_GRAPH
- {
- unsigned long elm;
- bitset_foreach(live, elm) {
- int live_nr = (int) elm;
- ir_node *live_irn = get_irn_for_graph_nr(irg, live_nr);
- if(is_phi_operand(live_irn)) {
- add_if(env, nr, live_nr);
- }
- }
- }
-#endif
- }
-
- /*
- * If the node is no phi node we can examine the uses.
- */
- if(!is_Phi(irn)) {
- for(i = 0, n = get_irn_arity(irn); i < n; ++i) {
- ir_node *op = get_irn_n(irn, i);
-
- if(is_allocatable_irn(op)) {
- int nr = get_irn_graph_nr(op);
-
- DBG((dbg, LEVEL_4, "\t\tpos: %d, use: %n\n", i, op));
-
- if(!bitset_is_set(live, nr)) {
- border_add(env, &head, op, step, 0);
- bitset_set(live, nr);
- }
- }
- }
- }
-
- ++step;
- }
-
- bitset_clear_all(live);
-
- /*
- * Add initial defs for all values live in.
- * Since their colors have already been assigned (The dominators were
- * allocated before), we have to mark their colors as used also.
- */
- for(irn = pset_first(live_in); irn; irn = pset_next(live_in)) {
- if(is_allocatable_irn(irn)) {
- int col = get_irn_color(irn);
-
- /* Mark the color of the live in value as used. */
- assert(is_color(col) && "Node must have been assigned a color.");
- bitset_set(colors, col);
- bitset_set(in_colors, col);
- bitset_set(used_colors, col);
-
- /* Mark the value live in. */
- bitset_set(live, get_irn_graph_nr(irn));
-
- /* Add the def */
- border_add(env, &head, irn, step, 1);
- }
- }
-
- DBG((dbg, LEVEL_4, "usedef chain for block %n\n", block));
- list_for_each_entry(border_t, b, &head, list) {
- DBG((dbg, LEVEL_4, "\t%s %n %d\n", b->is_def ? "def" : "use", b->irn, get_irn_graph_nr(b->irn)));
- }
-
- /*
- * Mind that the sequence of defs from back to front defines a perfect
- * elimination order. So, coloring the definitions from first to last
- * will work.
- */
- list_for_each_entry_reverse(border_t, b, &head, list) {
- const ir_node *irn = b->irn;
- int nr = get_irn_graph_nr(irn);
-
- /*
- * Assign a color, if it is a local def. Global defs already have a
- * color.
- */
- if(b->is_def && !is_live_in(block, irn)) {
- ra_node_info_t *ri = get_ra_node_info(irn);
- int col = NO_COLOR;
-
- DBG((dbg, LEVEL_4, "colors in use: %b\n", colors));
-
- /*
- * Try to assign live out values colors which are not used by live
- * in values.
- */
- if(is_live_out(block, irn)) {
- bitset_copy(tmp_colors, colors);
- bitset_or(tmp_colors, in_colors);
- col = bitset_next_clear(tmp_colors, 0);
- DBG((dbg, LEVEL_5, "next clear in only outs %b: %d\n", tmp_colors, col));
- }
-
- /* If a color is not yet assigned, do it now. */
- if(!is_color(col))
- col = bitset_next_clear(colors, 0);
-
- assert(!is_color(get_irn_color(irn)) && "Color must not have assigned");
- assert(!bitset_is_set(live, nr) && "Value def must not have been encountered");
-
- bitset_set(colors, col);
- bitset_set(used_colors, col);
- bitset_set(live, nr);
-
- ri->color = col;
- ri->pressure = bitset_popcnt(colors);
-
- DBG((dbg, LEVEL_1, "\tassigning color %d to %n\n", col, irn));
- }
-
- /* Clear the color upon a use. */
- else if(!b->is_def) {
- int col = get_irn_color(irn);