use custom spillslot coalescer so int->float and float->int gets proper spillslots

[r27824]

ir/be/sparc/bearch_sparc.c

@@ -230,11 +230,57 @@ static void sparc_after_ra_walker(ir_node *block, void *data)
 	}
 }
 
+static void sparc_collect_frame_entity_nodes(ir_node *node, void *data)
+{
+	be_fec_env_t  *env = data;
+	const ir_mode *mode;
+	int            align;
+	ir_entity     *entity;
+	const sparc_load_store_attr_t *attr;
+
+	if (be_is_Reload(node) && be_get_frame_entity(node) == NULL) {
+		mode  = get_irn_mode(node);
+		align = get_mode_size_bytes(mode);
+		be_node_needs_frame_entity(env, node, mode, align);
+		return;
+	}
+
+	if (!is_sparc_Ld(node) && !is_sparc_Ldf(node))
+		return;
+
+	attr   = get_sparc_load_store_attr_const(node);
+	entity = attr->entity;
+	mode   = attr->load_store_mode;
+	align  = get_mode_size_bytes(mode);
+	if (entity != NULL)
+		return;
+	if (!attr->is_frame_entity)
+		return;
+	be_node_needs_frame_entity(env, node, mode, align);
+}
+
+static void sparc_set_frame_entity(ir_node *node, ir_entity *entity)
+{
+	if (is_be_node(node)) {
+		be_node_set_frame_entity(node, entity);
+	} else {
+		/* we only say be_node_needs_frame_entity on nodes with load_store
+		 * attributes, so this should be fine */
+		sparc_load_store_attr_t *attr = get_sparc_load_store_attr(node);
+		attr->entity = entity;
+	}
+}
+
 
 static void sparc_after_ra(void *self)
 {
-	sparc_code_gen_t *cg = self;
-	be_coalesce_spillslots(cg->irg);
+	sparc_code_gen_t *cg      = self;
+	ir_graph         *irg     = cg->irg;
+	be_fec_env_t     *fec_env = be_new_frame_entity_coalescer(irg);
+
+	irg_walk_graph(irg, NULL, sparc_collect_frame_entity_nodes, fec_env);
+	be_assign_entities(fec_env, sparc_set_frame_entity);
+	be_free_frame_entity_coalescer(fec_env);
 
 	irg_block_walk_graph(cg->irg, NULL, sparc_after_ra_walker, NULL);
 }