Speed up RN by explicitely reducing the incident edges.
[libfirm] / pbqp_node.c
1 /*
2  * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
3  *
4  * This file is part of libFirm.
5  *
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.
10  *
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.
14  *
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
17  * PURPOSE.
18  */
19
20 /**
21  * @file
22  * @brief   PBQP nodes.
23  * @date    02.10.2008
24  * @author  Sebastian Buchwald
25  * @version $Id$
26  */
27 #include "config.h"
28
29 #include "adt/array.h"
30
31 #include "assert.h"
32
33 #include "bucket.h"
34 #include "pbqp_edge.h"
35 #include "pbqp_edge_t.h"
36 #include "pbqp_node.h"
37 #include "pbqp_node_t.h"
38 #include "vector.h"
39
40 pbqp_node *alloc_node(pbqp *pbqp, unsigned node_index, vector *costs)
41 {
42         pbqp_node *node = obstack_alloc(&pbqp->obstack, sizeof(*node));
43         assert(node);
44
45         node->edges = NEW_ARR_F(pbqp_edge *, 0);
46         node->costs = vector_copy(pbqp, costs);
47         node->bucket_index = UINT_MAX;
48         node->solution = UINT_MAX;
49         node->index = node_index;
50
51         return node;
52 }
53
54 int is_connected(pbqp_node *node, pbqp_edge *edge)
55 {
56         pbqp_edge **edges;
57         unsigned    edge_index;
58         unsigned    edge_len;
59
60         assert(node);
61         assert(edge);
62
63         if (edge->src != node && edge->tgt != node) return 0;
64
65         edges = node->edges;
66         edge_len = ARR_LEN(edges);
67
68         for (edge_index = 0; edge_index < edge_len; ++edge_index) {
69                 pbqp_edge *edge_candidate = edges[edge_index];
70                 if (edge_candidate == edge) {
71                         return 1;
72                 }
73         }
74
75         return 0;
76 }
77
78 void disconnect_edge(pbqp_node *node, pbqp_edge *edge)
79 {
80         pbqp_edge **edges;
81         unsigned    edge_index;
82         unsigned    edge_len;
83
84         edges = node->edges;
85         edge_len = ARR_LEN(edges);
86
87         for (edge_index = 0; edge_index < edge_len; ++edge_index) {
88                 pbqp_edge *edge_candidate = edges[edge_index];
89                 if (edge_candidate == edge) {
90                         edges[edge_index] = edges[edge_len - 1];
91                         ARR_SHRINKLEN(edges, (int)edge_len - 1);
92                         break;
93                 }
94         }
95 }
96
97 unsigned pbqp_node_get_degree(pbqp_node *node)
98 {
99         assert(node);
100         return ARR_LEN(node->edges);
101 }
102
103 pbqp_node *pbqp_node_deep_copy(pbqp *pbqp, pbqp_node_bucket new_bucket, pbqp_node *node)
104 {
105         unsigned   edge_index;
106         unsigned   edge_length = pbqp_node_get_degree(node);
107         pbqp_node *copy        = obstack_alloc(&pbqp->obstack, sizeof(*node));
108         assert(copy);
109
110         copy->edges        = NEW_ARR_F(pbqp_edge *, 0);
111         for (edge_index = 0; edge_index < edge_length; ++edge_index) {
112                 pbqp_edge *edge_copy;
113                 pbqp_edge *edge        = node->edges[edge_index];
114                 int        is_src      = edge->src == node;
115
116                 if (is_src) {
117                         unsigned other_index = edge->tgt->bucket_index;
118                         unsigned is_copied   = other_index < node->bucket_index;
119
120                         if (is_copied) {
121                                 pbqp_node *other_copy = new_bucket[other_index];
122                                 unsigned degree = pbqp_node_get_degree(other_copy);
123                                 unsigned index;
124
125                                 for (index = 0; index < degree; ++index) {
126                                         if (other_copy->edges[index]->src == node) {
127                                                 edge_copy      = other_copy->edges[index];
128                                                 edge_copy->src = copy;
129                                                 break;
130                                         }
131                                 }
132                         } else {
133                                 edge_copy = pbqp_edge_deep_copy(pbqp, edge, copy, edge->tgt);
134                         }
135                 } else {
136                         unsigned other_index = edge->src->bucket_index;
137                         unsigned is_copied   = other_index < node->bucket_index;
138
139                         if (is_copied) {
140                                 pbqp_node *other_copy = new_bucket[other_index];
141                                 unsigned degree = pbqp_node_get_degree(other_copy);
142                                 unsigned index;
143
144                                 for (index = 0; index < degree; ++index) {
145                                         if (other_copy->edges[index]->tgt == node) {
146                                                 edge_copy      = other_copy->edges[index];
147                                                 edge_copy->tgt = copy;
148                                                 break;
149                                         }
150                                 }
151                         } else {
152                                 edge_copy = pbqp_edge_deep_copy(pbqp, edge, edge->src, copy);
153                         }
154                 }
155                 ARR_APP1(pbqp_edge *, copy->edges, edge_copy);
156         }
157         copy->costs        = vector_copy(pbqp, node->costs);
158         copy->bucket_index = node->bucket_index;
159         copy->solution     = node->solution;
160         copy->index   = node->index;
161
162         return copy;
163 }