2 * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * @brief Random node selector.
23 * @author Matthias Braun
32 #include "belistsched.h"
36 * The random selector:
37 * Just assure that branches are executed last, otherwise select a random node
39 static ir_node *random_select(void *block_env, ir_nodeset_t *ready_set)
41 ir_nodeset_iterator_t iter;
43 int only_branches_left = 1;
46 /* assure that branches and constants are executed last */
47 ir_nodeset_iterator_init(&iter, ready_set);
48 while ( (irn = ir_nodeset_iterator_next(&iter)) != NULL) {
50 only_branches_left = 0;
55 if (only_branches_left) {
56 /* at last: schedule branches */
57 ir_nodeset_iterator_init(&iter, ready_set);
58 irn = ir_nodeset_iterator_next(&iter);
61 /* take 1 random node */
62 int n = rand() % ir_nodeset_size(ready_set);
64 ir_nodeset_iterator_init(&iter, ready_set);
65 while ((irn = ir_nodeset_iterator_next(&iter)) != NULL) {
71 } while (is_cfop(irn));
77 static void *random_init_graph(ir_graph *irg)
80 /* TODO: add commandline option for the seed */
85 static void *random_init_block(void *graph_env, ir_node *block)
92 static void sched_random(ir_graph *irg)
94 static const list_sched_selector_t random_selector = {
98 NULL, /* node_ready */
99 NULL, /* node_selected */
100 NULL, /* finish_block */
101 NULL /* finish_graph */
103 be_list_sched_graph(irg, &random_selector);
106 BE_REGISTER_MODULE_CONSTRUCTOR(be_init_sched_rand)
107 void be_init_sched_rand(void)
109 be_register_scheduler("random", sched_random);