X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbeifg.c;h=514caa772cdc8130cac330dbb6722e9158f22b21;hb=29087feac9466883c278e53eec325d5e3099df1d;hp=75e34055dac95141d1ee67f8b571c1241674fcf9;hpb=cef18ca838e9ae77a4b962b4a3baab81e3f2dce8;p=libfirm

diff --git a/ir/be/beifg.c b/ir/be/beifg.c
index 75e34055d..514caa772 100644
--- a/ir/be/beifg.c
+++ b/ir/be/beifg.c
@@ -1,595 +1,380 @@
-/**
- * @file   beifg.c
- * @date   18.11.2005
- * @author Sebastian Hack
+/*
+ * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
+ *
+ * This file is part of libFirm.
+ *
+ * This file may be distributed and/or modified under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation and appearing in the file LICENSE.GPL included in the
+ * packaging of this file.
  *
- * Copyright (C) 2005 Universitaet Karlsruhe
- * Released under the GPL
+ * Licensees holding valid libFirm Professional Edition licenses may use
+ * this file in accordance with the libFirm Commercial License.
+ * Agreement provided with the Software.
+ *
+ * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+ * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE.
  */
 
-#include <stdlib.h>
-
-#ifdef HAVE_CONFIG_H
+/**
+ * @file
+ * @brief       Interface for interference graphs.
+ * @author      Sebastian Hack
+ * @date        18.11.2005
+ */
 #include "config.h"
-#endif
-
-#ifdef HAVE_MALLOC_H
-#include <malloc.h>
-#endif
 
-#ifdef __linux__
-#include <malloc.h>
-#endif /* __linux__ */
-
-#ifdef HAVE_ALLOCA_H
-#include <alloca.h>
-#endif
+#include <stdlib.h>
 
-#ifdef WITH_LIBCORE
-#include <libcore/lc_opts.h>
-#include <libcore/lc_opts_enum.h>
-#include <libcore/lc_timing.h>
-#endif /* WITH_LIBCORE */
+#include "lc_opts.h"
+#include "lc_opts_enum.h"
 
+#include "timing.h"
 #include "bitset.h"
-
 #include "irgwalk.h"
 #include "irnode_t.h"
 #include "irprintf.h"
 #include "irtools.h"
-#include "beifg_t.h"
-#include "beifg_impl.h"
-#include "irphase.h"
-#include "irphase_t.h"
-#include "bechordal.h"
+#include "beifg.h"
+#include "error.h"
+#include "xmalloc.h"
 
 #include "becopystat.h"
 #include "becopyopt.h"
+#include "beirg.h"
+#include "bemodule.h"
+#include "beintlive_t.h"
 
-/** Defines values for the ifg performance test */
-#define BE_CH_PERFORMANCETEST_MIN_NODES (50)
-#define BE_CH_PERFORMANCETEST_COUNT (500)
-
-typedef struct _coloring_t coloring_t;
-
-struct _coloring_t {
-	phase_t ph;
-	const arch_env_t *arch_env;
-	ir_graph *irg;
-};
-
-size_t (be_ifg_nodes_iter_size)(const void *self)
+void be_ifg_free(be_ifg_t *self)
 {
-	const be_ifg_t *ifg = self;
-	return ifg->impl->nodes_iter_size;
+	free(self);
 }
 
-size_t (be_ifg_neighbours_iter_size)(const void *self)
+int be_ifg_connected(const be_ifg_t *ifg, const ir_node *a, const ir_node *b)
 {
-	const be_ifg_t *ifg = self;
-	return ifg->impl->neighbours_iter_size;
+	be_lv_t *lv = be_get_irg_liveness(ifg->env->irg);
+	return be_values_interfere(lv, a, b);
 }
 
-size_t (be_ifg_cliques_iter_size)(const void *self)
+static void nodes_walker(ir_node *bl, void *data)
 {
-	const be_ifg_t *ifg = self;
-	return ifg->impl->cliques_iter_size;
-}
+	nodes_iter_t     *it   = (nodes_iter_t*)data;
+	struct list_head *head = get_block_border_head(it->env, bl);
 
-static void *regs_irn_data_init(phase_t *ph, ir_node *irn, void *data)
-{
-	coloring_t *coloring = (coloring_t *) ph;
-	return (void *) arch_get_irn_register(coloring->arch_env, irn);
+	foreach_border_head(head, b) {
+		if (b->is_def && b->is_real) {
+			obstack_ptr_grow(&it->obst, b->irn);
+			it->n++;
+		}
+	}
 }
 
-coloring_t *coloring_init(coloring_t *c, ir_graph *irg, const arch_env_t *aenv)
+static void find_nodes(const be_ifg_t *ifg, nodes_iter_t *iter)
 {
-	phase_init(&c->ph, "regs_map", irg, PHASE_DEFAULT_GROWTH, regs_irn_data_init);
-	c->arch_env = aenv;
-	c->irg = irg;
-	return c;
+	obstack_init(&iter->obst);
+	iter->n     = 0;
+	iter->curr  = 0;
+	iter->env   = ifg->env;
+
+	irg_block_walk_graph(ifg->env->irg, nodes_walker, NULL, iter);
+	obstack_ptr_grow(&iter->obst, NULL);
+	iter->nodes = (ir_node**)obstack_finish(&iter->obst);
 }
 
-static void get_irn_color(ir_node *irn, void *c)
+static inline void node_break(nodes_iter_t *it, int force)
 {
-	coloring_t *coloring = c;
-	phase_get_or_set_irn_data(&coloring->ph, irn);
+	if ((it->curr >= it->n || force) && it->nodes) {
+		obstack_free(&it->obst, NULL);
+		it->nodes = NULL;
+	}
 }
 
-static void restore_irn_color(ir_node *irn, void *c)
+static ir_node *get_next_node(nodes_iter_t *it)
 {
-	coloring_t *coloring = c;
-	const arch_register_t *reg = phase_get_irn_data(&coloring->ph, irn);
-	if(reg)
-		arch_set_irn_register(coloring->arch_env, irn, reg);
-}
+	ir_node *res = NULL;
 
-void coloring_save(coloring_t *c)
-{
-	irg_walk_graph(c->irg, NULL, get_irn_color, c);
-}
+	if (it->curr < it->n)
+		res = it->nodes[it->curr++];
 
-void coloring_restore(coloring_t *c)
-{
-	irg_walk_graph(c->irg, NULL, restore_irn_color, c);
-}
+	node_break(it, 0);
 
-void (be_ifg_free)(void *self)
-{
-	be_ifg_t *ifg = self;
-	ifg->impl->free(self);
+	return res;
 }
 
-int (be_ifg_connected)(const void *self, const ir_node *a, const ir_node *b)
+ir_node *be_ifg_nodes_begin(const be_ifg_t *ifg, nodes_iter_t *iter)
 {
-	const be_ifg_t *ifg = self;
-	return ifg->impl->connected(self, a, b);
+	find_nodes(ifg, iter);
+	return get_next_node(iter);
 }
 
-ir_node *(be_ifg_neighbours_begin)(const void *self, void *iter, const ir_node *irn)
+ir_node *be_ifg_nodes_next(nodes_iter_t *iter)
 {
-	const be_ifg_t *ifg = self;
-	return ifg->impl->neighbours_begin(self, iter, irn);
+	return get_next_node(iter);
 }
 
-ir_node *(be_ifg_neighbours_next)(const void *self, void *iter)
+void be_ifg_nodes_break(nodes_iter_t *iter)
 {
-	const be_ifg_t *ifg = self;
-	return ifg->impl->neighbours_next(self, iter);
+	node_break(iter, 1);
 }
 
-void (be_ifg_neighbours_break)(const void *self, void *iter)
+static void find_neighbour_walker(ir_node *block, void *data)
 {
-	const be_ifg_t *ifg = self;
-	ifg->impl->neighbours_break(self, iter);
-}
+	neighbours_iter_t *it    = (neighbours_iter_t*)data;
+	struct list_head  *head  = get_block_border_head(it->env, block);
+	be_lv_t           *lv    = be_get_irg_liveness(it->env->irg);
 
-ir_node *(be_ifg_nodes_begin)(const void *self, void *iter)
-{
-	const be_ifg_t *ifg = self;
-	return ifg->impl->nodes_begin(self, iter);
-}
+	int has_started = 0;
 
-ir_node *(be_ifg_nodes_next)(const void *self, void *iter)
-{
-	const be_ifg_t *ifg = self;
-	return ifg->impl->nodes_next(self, iter);
-}
+	if (!be_is_live_in(lv, block, it->irn) && block != get_nodes_block(it->irn))
+		return;
 
-void (be_ifg_nodes_break)(const void *self, void *iter)
-{
-	const be_ifg_t *ifg = self;
-	ifg->impl->nodes_break(self, iter);
-}
+	foreach_border_head(head, b) {
+		ir_node *irn = b->irn;
 
-int (be_ifg_cliques_begin)(const void *self, void *iter, ir_node **buf)
-{
-	const be_ifg_t *ifg = self;
-	return ifg->impl->cliques_begin(self, iter, buf);
-}
+		if (irn == it->irn) {
+			if (b->is_def)
+				has_started = 1;
+			else
+				break; /* if we reached the end of the node's lifetime we can safely break */
+		}
+		else if (b->is_def) {
+			/* if any other node than the one in question starts living, add it to the set */
+			ir_nodeset_insert(&it->neighbours, irn);
+		}
+		else if (!has_started) {
+			/* we only delete, if the live range in question has not yet started */
+			ir_nodeset_remove(&it->neighbours, irn);
+		}
 
-int (be_ifg_cliques_next)(const void *self, void *iter)
-{
-	const be_ifg_t *ifg = self;
-	return ifg->impl->cliques_next(self, iter);
+	}
 }
 
-void (be_ifg_cliques_break)(const void *self, void *iter)
+static void find_neighbours(const be_ifg_t *ifg, neighbours_iter_t *it, const ir_node *irn)
 {
-	const be_ifg_t *ifg = self;
-	ifg->impl->cliques_break(self, iter);
+	it->env         = ifg->env;
+	it->irn         = irn;
+	it->valid       = 1;
+	ir_nodeset_init(&it->neighbours);
+
+	dom_tree_walk(get_nodes_block(irn), find_neighbour_walker, NULL, it);
+
+	ir_nodeset_iterator_init(&it->iter, &it->neighbours);
 }
 
-int (be_ifg_degree)(const void *self, const ir_node *irn)
+static inline void neighbours_break(neighbours_iter_t *it, int force)
 {
-	const be_ifg_t *ifg = self;
-	return ifg->impl->degree(self, irn);
+	(void) force;
+	assert(it->valid == 1);
+	ir_nodeset_destroy(&it->neighbours);
+	it->valid = 0;
 }
 
-
-int be_ifg_is_simplicial(const be_ifg_t *ifg, const ir_node *irn)
+static ir_node *get_next_neighbour(neighbours_iter_t *it)
 {
-	int degree = be_ifg_degree(ifg, irn);
-	void *iter = be_ifg_neighbours_iter_alloca(ifg);
-
-	ir_node **neighbours = xmalloc(degree * sizeof(neighbours[0]));
+	ir_node *res = ir_nodeset_iterator_next(&it->iter);
 
-	ir_node *curr;
-	int i, j;
-
-	i = 0;
-	be_ifg_foreach_neighbour(ifg, iter, irn, curr)
-		neighbours[i++] = curr;
-
-	for(i = 0; i < degree; ++i) {
-		for(j = 0; j < i; ++j)
-			if(!be_ifg_connected(ifg, neighbours[i], neighbours[j])) {
-				free(neighbours);
-				return 0;
-			}
+	if (res == NULL) {
+		ir_nodeset_destroy(&it->neighbours);
 	}
-
-
-	free(neighbours);
-	return 1;
+	return res;
 }
 
-void be_ifg_check(const be_ifg_t *ifg)
+ir_node *be_ifg_neighbours_begin(const be_ifg_t *ifg, neighbours_iter_t *iter,
+                                 const ir_node *irn)
 {
-	void *iter1 = be_ifg_nodes_iter_alloca(ifg);
-	void *iter2 = be_ifg_neighbours_iter_alloca(ifg);
-
-	ir_node *n, *m;
-	int node_count = 0;
-	int neighbours_count = 0;
-	int degree = 0;
-
-	/* count all nodes */
-	ir_printf("\n\nFound the following nodes in the graph %+F:\n\n", current_ir_graph);
-	be_ifg_foreach_node(ifg,iter1,n)
-	{
-		node_count++;
-		degree = be_ifg_degree(ifg, n);
-		ir_printf("%d. %+F with degree: %d\n", node_count, n, degree);
-	}
-
-	ir_printf("\n\nNumber of nodes: %d\n\n", node_count);
-
-	/* Check, if all neighbours are indeed connected to the node. */
-	be_ifg_foreach_node(ifg, iter1, n)
-	{
-		ir_printf("\n%+F; ", n);
-		be_ifg_foreach_neighbour(ifg, iter2, n, m)
-		{
-			ir_printf("%+F; ", m);
-			neighbours_count++;
-			if(!be_ifg_connected(ifg, n, m))
-				ir_fprintf(stderr, "%+F is a neighbour of %+F but they are not connected!\n", n, m);
-		}
-	}
-	ir_printf("\n\nFound %d nodes in the 'check neighbour section'\n", neighbours_count);
+	find_neighbours(ifg, iter, irn);
+	return get_next_neighbour(iter);
 }
 
-int be_ifg_check_get_node_count(const be_ifg_t *ifg)
+ir_node *be_ifg_neighbours_next(neighbours_iter_t *iter)
 {
-	void *iter = be_ifg_nodes_iter_alloca(ifg);
-	int node_count = 0;
-	ir_node *n;
-
-	be_ifg_foreach_node(ifg, iter, n)
-	{
-		node_count++;
-	}
-
-	return node_count;
+	return get_next_neighbour(iter);
 }
 
-static int be_ifg_check_cmp_nodes(const void *a, const void *b)
+void be_ifg_neighbours_break(neighbours_iter_t *iter)
 {
-	const ir_node *node_a = *(ir_node **)a;
-	const ir_node *node_b = *(ir_node **)b;
-
-	int nr_a = node_a->node_nr;
-	int nr_b = node_b->node_nr;
-
-	return QSORT_CMP(nr_a, nr_b);
+	neighbours_break(iter, 1);
 }
 
-void be_ifg_check_sorted(const be_ifg_t *ifg)
+static inline void free_clique_iter(cliques_iter_t *it)
 {
-	void *iter1 = be_ifg_nodes_iter_alloca(ifg);
-	void *iter2 = be_ifg_neighbours_iter_alloca(ifg);
-
-	ir_node *n, *m;
-	const int node_count = be_ifg_check_get_node_count(ifg);
-	int neighbours_count = 0;
-	int i = 0;
-
-	ir_node **all_nodes = xmalloc(node_count * sizeof(all_nodes[0]));
-
-	be_ifg_foreach_node(ifg, iter1, n)
-	{
-		if(!node_is_in_irgs_storage(ifg->env->irg, n))
-		{
-			printf ("+%F is in ifg but not in the current irg!",n);
-			assert (node_is_in_irgs_storage(ifg->env->irg, n));
-		}
-
-		all_nodes[i] = n;
-		i++;
-	}
-
-	qsort(all_nodes, node_count, sizeof(all_nodes[0]), be_ifg_check_cmp_nodes);
-
-	for (i = 0; i < node_count; i++)
-	{
-		ir_node **neighbours = xmalloc(node_count * sizeof(neighbours[0]));
-		int j = 0;
-		int k = 0;
-		int degree = 0;
-
-		degree = be_ifg_degree(ifg, all_nodes[i]);
-
-		be_ifg_foreach_neighbour(ifg, iter2, all_nodes[i], m)
-		{
-			neighbours[j] = m;
-			j++;
-		}
-
-		qsort(neighbours, j, sizeof(neighbours[0]), be_ifg_check_cmp_nodes);
-
-		ir_printf("%d. %+F's neighbours(%d): ", i+1, all_nodes[i], degree);
-
-		for(k = 0; k < j; k++)
-		{
-			ir_printf("%+F, ", neighbours[k]);
-		}
-
-		ir_printf("\n");
-
-		free(neighbours);
-	}
-
-	free(all_nodes);
-
+	it->n_blocks = -1;
+	obstack_free(&it->ob, NULL);
+	del_pset(it->living);
 }
 
-void be_ifg_check_performance(be_chordal_env_t *chordal_env)
+static void get_blocks_dom_order(ir_node *blk, void *env)
 {
-	int tests = BE_CH_PERFORMANCETEST_COUNT;
-	coloring_t coloring;
-
-	int used_memory;
-
-	int i = 0;
-	int rt;
-	copy_opt_t *co;
-	be_ifg_t *old_if = chordal_env->ifg;
-
-	lc_timer_t *timer = lc_timer_register("getTime","get Time of copy minimization using the ifg");
-	unsigned long elapsed_usec = 0;
-
-	if ((int) get_irg_estimated_node_cnt >= BE_CH_PERFORMANCETEST_MIN_NODES)
-	{
-		coloring_init(&coloring, chordal_env->irg, chordal_env->birg->main_env->arch_env);
-		coloring_save(&coloring);
-
-		lc_timer_reset(timer);
-
-		for (i = 0; i<tests; i++) /* performance test with std */
-		{
-
-			used_memory = lc_get_heap_used_bytes();
-
-			rt = lc_timer_enter_high_priority();
-			lc_timer_start(timer);
-
-			chordal_env->ifg = be_ifg_std_new(chordal_env);
-
-			lc_timer_stop(timer);
-			rt = lc_timer_leave_high_priority();
-
-			used_memory = lc_get_heap_used_bytes() - used_memory;
-
-			coloring_restore(&coloring);
-
-			co = NULL;
-			co = new_copy_opt(chordal_env, co_get_costs_loop_depth);
-			co_build_ou_structure(co);
-			co_build_graph_structure(co);
-
-			rt = lc_timer_enter_high_priority();
-			lc_timer_start(timer);
-
-			co_solve_heuristic_new(co);
-
-			lc_timer_stop(timer);
-			rt = lc_timer_leave_high_priority();
-
-			co_free_graph_structure(co);
-			co_free_ou_structure(co);
-			free_copy_opt(co);
-			be_ifg_free(chordal_env->ifg);
-
-		}
-
-		elapsed_usec = lc_timer_elapsed_usec(timer);
-		/* calculating average */
-		elapsed_usec = elapsed_usec / tests;
-
-		ir_printf("\nstd:; %+F; %u; %u ",current_ir_graph, used_memory, elapsed_usec);
-
-		i=0;
-		used_memory=0;
-		elapsed_usec=0;
-
-		for (i = 0; i<tests; i++)  /* performance test with clique */
-		{
-			used_memory = lc_get_heap_used_bytes();
-
-			rt = lc_timer_enter_high_priority();
-			lc_timer_start(timer);
+	cliques_iter_t *it = (cliques_iter_t*)env;
+	obstack_ptr_grow(&it->ob, blk);
+}
 
-			chordal_env->ifg = be_ifg_clique_new(chordal_env);
+/**
+ * NOTE: Be careful when changing this function!
+ *       First understand the control flow of consecutive calls.
+ */
+static inline int get_next_clique(cliques_iter_t *it)
+{
 
-			lc_timer_stop(timer);
-			rt = lc_timer_leave_high_priority();
+	/* continue in the block we left the last time */
+	for (; it->blk < it->n_blocks; it->blk++) {
+		int output_on_shrink = 0;
+		struct list_head *head = get_block_border_head(it->cenv, it->blocks[it->blk]);
 
-			used_memory = lc_get_heap_used_bytes() - used_memory;
+		/* on entry to a new block set the first border ... */
+		if (!it->bor)
+			it->bor = head->prev;
 
-			coloring_restore(&coloring);
+		/* ... otherwise continue with the border we left the last time */
+		for (; it->bor != head; it->bor = it->bor->prev) {
+			border_t *b = list_entry(it->bor, border_t, list);
 
-			co = NULL;
-			co = new_copy_opt(chordal_env, co_get_costs_loop_depth);
-			co_build_ou_structure(co);
-			co_build_graph_structure(co);
+			/* if its a definition irn starts living */
+			if (b->is_def) {
+				pset_insert_ptr(it->living, b->irn);
+				if (b->is_real)
+					output_on_shrink = 1;
+			} else
 
-			rt = lc_timer_enter_high_priority();
-			lc_timer_start(timer);
+			/* if its the last usage the irn dies */
+			{
+				/* before shrinking the set, return the current maximal clique */
+				if (output_on_shrink) {
+					int count = 0;
 
-			co_solve_heuristic_new(co);
+					/* fill the output buffer */
+					foreach_pset(it->living, ir_node, irn) {
+						it->buf[count++] = irn;
+					}
 
-			lc_timer_stop(timer);
-			rt = lc_timer_leave_high_priority();
+					assert(count > 0 && "We have a 'last usage', so there must be sth. in it->living");
 
-			co_free_graph_structure(co);
-			co_free_ou_structure(co);
-			free_copy_opt(co);
-			be_ifg_free(chordal_env->ifg);
+					return count;
+				}
 
+				pset_remove_ptr(it->living, b->irn);
+			}
 		}
 
-		elapsed_usec = lc_timer_elapsed_usec(timer);
-		/* calculating average */
-		elapsed_usec = elapsed_usec / tests;
-
-		ir_printf("\nclique:; %+F; %u; %u ",current_ir_graph, used_memory, elapsed_usec);
-
-		i=0;
-		used_memory=0;
-		elapsed_usec=0;
-
-		for (i = 0; i<tests; i++)  /* performance test with list */
-		{
-			used_memory = lc_get_heap_used_bytes();
-
-			rt = lc_timer_enter_high_priority();
-			lc_timer_start(timer);
-
-			chordal_env->ifg = be_ifg_list_new(chordal_env);
-
-			lc_timer_stop(timer);
-			rt = lc_timer_leave_high_priority();
-
-			used_memory = lc_get_heap_used_bytes() - used_memory;
-
-			coloring_restore(&coloring);
-
-			co = NULL;
-			co = new_copy_opt(chordal_env, co_get_costs_loop_depth);
-			co_build_ou_structure(co);
-			co_build_graph_structure(co);
-
-			rt = lc_timer_enter_high_priority();
-			lc_timer_start(timer);
-
-			co_solve_heuristic_new(co);
+		it->bor = NULL;
+		assert(0 == pset_count(it->living) && "Something has survived! (At the end of the block it->living must be empty)");
+	}
 
-			lc_timer_stop(timer);
-			rt = lc_timer_leave_high_priority();
+	if (it->n_blocks != -1)
+		free_clique_iter(it);
 
-			co_free_graph_structure(co);
-			co_free_ou_structure(co);
-			free_copy_opt(co);
-			be_ifg_free(chordal_env->ifg);
+	return -1;
+}
 
-		}
+int be_ifg_cliques_begin(const be_ifg_t *ifg, cliques_iter_t *it,
+                         ir_node **buf)
+{
+	ir_node *start_bl = get_irg_start_block(ifg->env->irg);
 
-		elapsed_usec = lc_timer_elapsed_usec(timer);
-		/* calculating average */
-		elapsed_usec = elapsed_usec / tests;
+	obstack_init(&it->ob);
+	dom_tree_walk(start_bl, get_blocks_dom_order, NULL, it);
 
-		ir_printf("\nlist:; %+F; %u; %u ",current_ir_graph, used_memory, elapsed_usec);
+	it->cenv     = ifg->env;
+	it->buf      = buf;
+	it->n_blocks = obstack_object_size(&it->ob) / sizeof(void *);
+	it->blocks   = (ir_node**)obstack_finish(&it->ob);
+	it->blk      = 0;
+	it->bor      = NULL;
+	it->living   = pset_new_ptr(2 * arch_register_class_n_regs(it->cenv->cls));
 
-		i=0;
-		used_memory=0;
-		elapsed_usec=0;
+	return get_next_clique(it);
+}
 
-		for (i = 0; i<tests; i++)  /* performance test with pointer */
-		{
-			used_memory = lc_get_heap_used_bytes();
+int be_ifg_cliques_next(cliques_iter_t *iter)
+{
+	return get_next_clique(iter);
+}
 
-			rt = lc_timer_enter_high_priority();
-			lc_timer_start(timer);
+void be_ifg_cliques_break(cliques_iter_t *iter)
+{
+	free_clique_iter(iter);
+}
 
-			chordal_env->ifg = be_ifg_pointer_new(chordal_env);
+int be_ifg_degree(const be_ifg_t *ifg, const ir_node *irn)
+{
+	neighbours_iter_t it;
+	int degree;
+	find_neighbours(ifg, &it, irn);
+	degree = ir_nodeset_size(&it.neighbours);
+	neighbours_break(&it, 1);
+	return degree;
+}
 
-			lc_timer_stop(timer);
-			rt = lc_timer_leave_high_priority();
+be_ifg_t *be_create_ifg(const be_chordal_env_t *env)
+{
+	be_ifg_t *ifg = XMALLOC(be_ifg_t);
+	ifg->env = env;
 
-			used_memory = lc_get_heap_used_bytes() - used_memory;
+	return ifg;
+}
 
-			coloring_restore(&coloring);
+static void int_comp_rec(be_ifg_t *ifg, ir_node *n, bitset_t *seen)
+{
+	neighbours_iter_t neigh_it;
+	ir_node *m;
 
-			co = NULL;
-			co = new_copy_opt(chordal_env, co_get_costs_loop_depth);
-			co_build_ou_structure(co);
-			co_build_graph_structure(co);
+	be_ifg_foreach_neighbour(ifg, &neigh_it, n, m) {
+		if (bitset_is_set(seen, get_irn_idx(m)))
+			continue;
 
-			rt = lc_timer_enter_high_priority();
-			lc_timer_start(timer);
+		arch_register_req_t const *const req = arch_get_irn_register_req(m);
+		if (arch_register_req_is(req, ignore))
+			continue;
 
-			co_solve_heuristic_new(co);
+		bitset_set(seen, get_irn_idx(m));
+		int_comp_rec(ifg, m, seen);
+	}
 
-			lc_timer_stop(timer);
-			rt = lc_timer_leave_high_priority();
+}
 
-			co_free_graph_structure(co);
-			co_free_ou_structure(co);
-			free_copy_opt(co);
-			be_ifg_free(chordal_env->ifg);
+static int int_component_stat(ir_graph *irg, be_ifg_t *ifg)
+{
+	int      n_comp    = 0;
+	nodes_iter_t nodes_it;
+	bitset_t *seen     = bitset_malloc(get_irg_last_idx(irg));
 
-		}
+	ir_node *n;
 
-		elapsed_usec = lc_timer_elapsed_usec(timer);
-		/* calculating average */
-		elapsed_usec = elapsed_usec / tests;
+	be_ifg_foreach_node(ifg, &nodes_it, n) {
+		if (bitset_is_set(seen, get_irn_idx(n)))
+			continue;
 
-		ir_printf("\npointer:; %+F; %u; %u ",current_ir_graph, used_memory, elapsed_usec);
+		arch_register_req_t const *const req = arch_get_irn_register_req(n);
+		if (arch_register_req_is(req, ignore))
+			continue;
 
-		i=0;
-		used_memory=0;
-		elapsed_usec=0;
+		++n_comp;
+		bitset_set(seen, get_irn_idx(n));
+		int_comp_rec(ifg, n, seen);
 	}
 
-	chordal_env->ifg = old_if;
+	free(seen);
+	return n_comp;
 }
 
-void be_ifg_dump_dot(be_ifg_t *ifg, ir_graph *irg, FILE *file, const be_ifg_dump_dot_cb_t *cb, void *self)
+void be_ifg_stat(ir_graph *irg, be_ifg_t *ifg, be_ifg_stat_t *stat)
 {
-	void *nodes_it  = be_ifg_nodes_iter_alloca(ifg);
-	void *neigh_it  = be_ifg_neighbours_iter_alloca(ifg);
-	bitset_t *nodes = bitset_malloc(get_irg_last_idx(irg));
-
-	ir_node *n, *m;
-
-	fprintf(file, "graph G {\n\tgraph [");
-	if(cb->graph_attr)
-		cb->graph_attr(file, self);
-	fprintf(file, "];\n");
-
-	if(cb->at_begin)
-		cb->at_begin(file, self);
-
-	be_ifg_foreach_node(ifg, nodes_it, n) {
-		if(cb->is_dump_node && cb->is_dump_node(self, n)) {
-			int idx = get_irn_idx(n);
-			bitset_set(nodes, idx);
-			fprintf(file, "\tnode [");
-			if(cb->node_attr)
-				cb->node_attr(file, self, n);
-			fprintf(file, "]; n%d;\n", idx);
-		}
-	}
-
-	/* Check, if all neighbours are indeed connected to the node. */
-	be_ifg_foreach_node(ifg, nodes_it, n) {
-		be_ifg_foreach_neighbour(ifg, neigh_it, n, m) {
-			int n_idx = get_irn_idx(n);
-			int m_idx = get_irn_idx(m);
-
-			if(n_idx < m_idx && bitset_is_set(nodes, n_idx) && bitset_is_set(nodes, m_idx)) {
-				fprintf(file, "\tn%d -- n%d [", n_idx, m_idx);
-				if(cb->edge_attr)
-					cb->edge_attr(file, self, n, m);
-				fprintf(file, "];\n");
-			}
+	nodes_iter_t      nodes_it;
+	neighbours_iter_t neigh_it;
+	bitset_t         *nodes    = bitset_malloc(get_irg_last_idx(irg));
+	ir_node          *n, *m;
+
+	memset(stat, 0, sizeof(stat[0]));
+
+	be_ifg_foreach_node(ifg, &nodes_it, n) {
+		stat->n_nodes += 1;
+		be_ifg_foreach_neighbour(ifg, &neigh_it, n, m) {
+			bitset_set(nodes, get_irn_idx(n));
+			stat->n_edges += !bitset_is_set(nodes, get_irn_idx(m));
 		}
 	}
 
-	if(cb->at_end)
-		cb->at_end(file, self);
-
-	fprintf(file, "}\n");
+	stat->n_comps = int_component_stat(irg, ifg);
 	bitset_free(nodes);
 }