From: Daniel Grund <grund@cs.uni-saarland.de>
Date: Tue, 14 Mar 2006 13:52:33 +0000 (+0000)
Subject: Added star constraints with all needed helpers
X-Git-Url: http://nsz.repo.hu/git/?a=commitdiff_plain;h=94b02881010e09aabe313564771b2e99273c4196;p=libfirm

Added star constraints with all needed helpers
---

diff --git a/ir/be/becopyilp2.c b/ir/be/becopyilp2.c
index 93cb74131..b323464e5 100644
--- a/ir/be/becopyilp2.c
+++ b/ir/be/becopyilp2.c
@@ -173,10 +173,176 @@ static void build_affinity_cstr(ilp_env_t *ienv) {
 }
 
 /**
- *
+ * Helping stuff for build_clique_star_cstr
+ */
+typedef struct _edge_t {
+	ir_node *n1, *n2;
+} edge_t;
+
+static int compare_edge_t(const void *k1, const void *k2, size_t size) {
+	const edge_t *e1 = k1;
+	const edge_t *e2 = k2;
+
+	return ! (e1->n1 == e2->n1   &&   e1->n2 == e2->n2);
+}
+
+#define HASH_EDGE(e) (HASH_PTR((e)->n1) ^ HASH_PTR((e)->n2))
+
+static INLINE edge_t *add_edge(set *edges, ir_node *n1, ir_node *n2, int *counter) {
+	edge_t new_edge;
+
+	if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
+		new_edge.n1 = n1;
+		new_edge.n2 = n2;
+	} else {
+		new_edge.n1 = n2;
+		new_edge.n2 = n1;
+	}
+	*counter++;
+	return set_insert(edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
+}
+
+static INLINE edge_t *find_edge(set *edges, ir_node *n1, ir_node *n2) {
+	edge_t new_edge;
+
+	if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
+		new_edge.n1 = n1;
+		new_edge.n2 = n2;
+	} else {
+		new_edge.n1 = n2;
+		new_edge.n2 = n1;
+	}
+	return set_find(edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
+}
+
+static INLINE void remove_edge(set *edges, ir_node *n1, ir_node *n2, int *counter) {
+	edge_t new_edge, *e;
+
+	if (PTR_TO_INT(n1) < PTR_TO_INT(n2)) {
+		new_edge.n1 = n1;
+		new_edge.n2 = n2;
+	} else {
+		new_edge.n1 = n2;
+		new_edge.n2 = n1;
+	}
+	e = set_find(edges, &new_edge, sizeof(new_edge), HASH_EDGE(&new_edge));
+	if (e) {
+		e->n1 = NULL;
+		e->n2 = NULL;
+		*counter--;
+	}
+}
+
+#define pset_foreach(pset, irn)  for(irn=pset_first(pset); irn; irn=pset_next(pset))
+
+/**
+ * Search for an interference clique and an external node
+ * with affinity edges to all nodes of the clique.
+ * At most 1 node of the clique can be colored equally with the external node.
  */
 static void build_clique_star_cstr(ilp_env_t *ienv) {
+	node_t *node;
+
+	/* for each node with affinity edges */
+	co_gs_foreach_node(ienv->co, node) {
+		struct obstack ob;
+		neighb_t *nbr;
+		ir_node *center = node->irn;
+		ir_node **nodes;
+		set *edges;
+		int i, o, n_nodes, n_edges;
+
+		obstack_init(&ob);
+		edges = new_set(compare_edge_t, 8);
+
+		/* get all affinity neighbours */
+		n_nodes = 0;
+		co_gs_foreach_neighb(node, nbr) {
+			obstack_ptr_grow(&ob, nbr->irn);
+			++n_nodes;
+		}
+		nodes = obstack_finish(&ob);
+
+		/* get all interference edges between these */
+		n_edges = 0;
+		for (i=0; i<n_nodes; ++i)
+			for (o=0; o<i; ++o)
+				if (be_ifg_connected(ienv->co->cenv->ifg, nodes[i], nodes[o]))
+					add_edge(edges, nodes[i], nodes[o], &n_edges);
+
+		/* cover all these interference edges with maximal cliques */
+		while (n_edges) {
+			edge_t *e;
+			pset *clique = pset_new_ptr(8);
+			int growed;
+
+			/* get 2 starting nodes to form a clique */
+			for (e=set_first(edges); !e->n1; e=set_next(edges))
+				/*nothing*/ ;
+
+			remove_edge(edges, e->n1, e->n2, &n_edges);
+			pset_insert_ptr(clique, e->n1);
+			pset_insert_ptr(clique, e->n2);
+
+			/* while the clique is growing */
+			do {
+				growed = 0;
+
+				/* search for a candidate to extend the clique */
+				for (i=0; i<n_nodes; ++i) {
+					ir_node *member, *cand = nodes[i];
+					int is_cand;
+
+					/* if its already in the clique try the next */
+					if (pset_find_ptr(clique, cand))
+						continue;
+
+					/* are there all necessary interferences? */
+					is_cand = 1;
+					pset_foreach(clique, member) {
+						if (!find_edge(edges, cand, member)) {
+							is_cand = 0;
+							pset_break(clique);
+							break;
+						}
+					}
+
+					/* now we know if we have a clique extender */
+					if (is_cand) {
+						/* first remove all covered edges */
+						pset_foreach(clique, member)
+							remove_edge(edges, cand, member, &n_edges);
+
+						/* insert into clique */
+						pset_insert_ptr(clique, cand);
+						growed = 1;
+						break;
+					}
+				}
+			} while (growed);
 
+			/* now the clique is maximal. Finally add the constraint */
+			{
+				ir_node *member;
+				int var_idx, cst_idx, center_nr, member_nr;
+				char buf[16];
+
+				cst_idx = lpp_add_cst(ienv->lp, NULL, lpp_greater, pset_count(clique)-1);
+				center_nr = get_irn_node_nr(center);
+
+				pset_foreach(clique, member) {
+					member_nr = get_irn_node_nr(member);
+					var_idx = lpp_get_var_idx(ienv->lp, name_cdd_sorted(buf, 'y', center_nr, member_nr));
+					lpp_set_factor_fast(ienv->lp, cst_idx, var_idx, 1.0);
+				}
+			}
+
+			del_pset(clique);
+		}
+
+		del_set(edges);
+		obstack_free(&ob, NULL);
+	}
 }
 
 /**
diff --git a/ir/be/becopyopt.c b/ir/be/becopyopt.c
index 3526c17ee..25989e71f 100644
--- a/ir/be/becopyopt.c
+++ b/ir/be/becopyopt.c
@@ -506,8 +506,12 @@ void co_free_graph_structure(copy_opt_t *co) {
 /* co_solve_ilp1() co_solve_ilp2() are implemented in becopyilpX.c */
 
 int co_gs_is_optimizable(copy_opt_t *co, ir_node *irn) {
-	node_t new_node;
+	node_t new_node, *n;
 
-	new_node.irn        = irn;
-	return (int)set_find(co->nodes, new_node.irn, sizeof(new_node), HASH_PTR(new_node.irn));
+	new_node.irn = irn;
+	n = set_find(co->nodes, new_node.irn, sizeof(new_node), HASH_PTR(new_node.irn));
+	if (n) {
+		return (n->count > 0);
+	} else
+		return 0;
 }
diff --git a/ir/be/becopyopt_t.h b/ir/be/becopyopt_t.h
index 9d16e8810..bee1e1598 100644
--- a/ir/be/becopyopt_t.h
+++ b/ir/be/becopyopt_t.h
@@ -69,13 +69,13 @@ struct _copy_opt_t {
 
 typedef struct _unit_t {
 	struct list_head units;		/**< chain for all units */
-	copy_opt_t *co;				/**< the copy_opt this unit belongs to */
+	copy_opt_t *co;				/**< the copy opt this unit belongs to */
 	int node_count;				/**< size of the nodes array */
 	ir_node **nodes;			/**< [0] is the root-node, others are non interfering args of it. */
 	int *costs;					/**< costs[i] are incurred, if nodes[i] has a different color */
 	int inevitable_costs;		/**< sum of costs of all args interfering with root */
 	int all_nodes_costs;		/**< sum of all costs[i] */
-	int min_nodes_costs;		/**< a lower bound for the costs in costs[], determined by a max indep. set */
+	int min_nodes_costs;		/**< a lower bound for the costs in costs[], determined by a max independent set */
 	int sort_key;				/**< maximum costs. controls the order of ou's in the struct list_head units. */
 
 	/* for heuristic */
@@ -96,6 +96,8 @@ typedef struct _unit_t {
  ******************************************************************************/
 
 typedef struct _neighb_t neighb_t;
+typedef struct _node_t node_t;
+
 
 struct _neighb_t {
 	neighb_t *next;			/** the next neighbour entry*/
@@ -103,11 +105,17 @@ struct _neighb_t {
 	int costs;				/** the costs of the edge (node_t->irn, neighb_t->irn) */
 };
 
-typedef struct _node_t {
+struct _node_t {
 	ir_node *irn;			/** a node with affinity edges */
 	int count;				/** number of affinity edges in the linked list below */
 	neighb_t *neighbours;	/** a linked list of all affinity neighbours */
-} node_t;
+};
+
+#define co_gs_nodes_begin(co)			set_first((co)->nodes)
+#define co_gs_nodes_next(co)			set_next((co)->nodes)
+#define co_gs_nodes_break(co)			set_break((co)->nodes)
+#define co_gs_foreach_node(co, node)	for (node = co_gs_nodes_begin(co); node; node = co_gs_nodes_next(co))
 
+#define co_gs_foreach_neighb(node, neighb)	for (neighb = node->neighbours; neighb; neighb = neighb->next)
 
 #endif