fixed some bugs
[libfirm] / ir / be / beifg_std.c
1 /**
2  * @file   beifg_std.c
3  * @date   18.11.2005
4  * @author Sebastian Hack
5  *
6  * Copyright (C) 2005 Universitaet Karlsruhe
7  * Released under the GPL
8  */
9
10 #ifdef HAVE_CONFIG_H
11 #include "config.h"
12 #endif
13
14 #include <stdlib.h>
15
16 #include "list.h"
17
18 #include "irnode_t.h"
19 #include "irgraph_t.h"
20 #include "irgwalk.h"
21
22 #include "be_t.h"
23 #include "belive_t.h"
24 #include "bera.h"
25 #include "beifg_t.h"
26 #include "bechordal_t.h"
27
28 #define MAX(x, y) ((x) > (y) ? (x) : (y))
29
30 typedef struct _ifg_std_t ifg_std_t;
31
32 struct _ifg_std_t {
33         const be_ifg_impl_t *impl;
34         const be_chordal_env_t *env;
35 };
36
37 static void ifg_std_free(void *self)
38 {
39         free(self);
40 }
41
42 static int ifg_std_connected(const void *self, const ir_node *a, const ir_node *b)
43 {
44         return values_interfere(a, b);
45 }
46
47 typedef struct _nodes_iter_t {
48         const be_chordal_env_t *env;
49         struct obstack obst;
50         int n;
51         int curr;
52         ir_node **nodes;
53 } nodes_iter_t;
54
55 static void nodes_walker(ir_node *bl, void *data)
56 {
57         nodes_iter_t *it = data;
58         struct list_head *head = get_block_border_head(it->env, bl);
59
60         border_t *b;
61
62         foreach_border_head(head, b) {
63                 if(b->is_def && b->is_real) {
64                         obstack_ptr_grow(&it->obst, b->irn);
65                         it->n++;
66                 }
67         }
68 }
69
70 static void find_nodes(const void *self, void *iter) {
71         const ifg_std_t *ifg = self;
72         nodes_iter_t *it = iter;
73
74         obstack_init(&it->obst);
75         it->n     = 0;
76         it->curr  = 0;
77         it->env   = ifg->env;
78
79         irg_block_walk_graph(ifg->env->irg, nodes_walker, NULL, iter);
80         it->nodes = obstack_finish(&it->obst);
81 }
82
83 static INLINE void node_break(nodes_iter_t *it, int force)
84 {
85         if((it->curr >= it->n || force) && it->nodes) {
86                 obstack_free(&it->obst, NULL);
87                 it->nodes = NULL;
88         }
89 }
90
91 static ir_node *get_next_node(void *iter)
92 {
93         nodes_iter_t *it = iter;
94         ir_node *res     = NULL;
95
96         if(it->curr < it->n)
97                 res = it->nodes[it->curr++];
98
99         node_break(it, 0);
100
101         return res;
102 }
103
104 static ir_node *ifg_std_nodes_begin(const void *self, void *iter)
105 {
106         find_nodes(self, iter);
107         return get_next_node(iter);
108 }
109
110 static ir_node *ifg_std_nodes_next(const void *self, void *iter)
111 {
112         return get_next_node(iter);
113 }
114
115 static void ifg_std_nodes_break(const void *self, void *iter)
116 {
117         node_break(iter, 1);
118 }
119
120 typedef struct _adj_iter_t {
121         const be_chordal_env_t *env;
122         const ir_node *irn;
123         int reached_end;
124         pset *neighbours;
125 } adj_iter_t;
126
127 static void find_neighbour_walker(ir_node *block, void *data)
128 {
129         adj_iter_t *it          = data;
130         struct list_head *head  = get_block_border_head(it->env, block);
131
132         border_t *b;
133         int has_started = 0;
134
135         if(!is_live_in(block, it->irn) && block != get_nodes_block(it->irn))
136                 return;
137
138         foreach_border_head(head, b) {
139                 ir_node *irn = b->irn;
140
141                 if(irn == it->irn) {
142                         if(b->is_def)
143                                 has_started = 1;
144                         else
145                                 break; /* if we reached the end of the node's lifetime we can safely break */
146                 }
147                 else if(b->is_def) {
148                         /* if any other node than the one in question starts living, add it to the set */
149                         pset_insert_ptr(it->neighbours, irn);
150                 }
151                 else if(!has_started) {
152                         /* we only delete, if the live range in question has not yet started */
153                         pset_remove_ptr(it->neighbours, irn);
154                 }
155
156         }
157 }
158
159 static void find_neighbours(const ifg_std_t *ifg, adj_iter_t *it, const ir_node *irn)
160 {
161         it->env         = ifg->env;
162         it->irn         = irn;
163         it->neighbours  = pset_new_ptr(16);
164         it->reached_end = 0;
165
166         dom_tree_walk(get_nodes_block(irn), find_neighbour_walker, NULL, it);
167 }
168
169 static INLINE void neighbours_break(adj_iter_t *it, int force)
170 {
171         if((it->reached_end || force) && it->neighbours) {
172                 del_pset(it->neighbours);
173                 it->neighbours = NULL;
174         }
175 }
176
177 static ir_node *get_next_neighbour(adj_iter_t *it) {
178         ir_node *res = pset_next(it->neighbours);
179
180         it->reached_end = res == NULL;
181         neighbours_break(it, 0);
182
183         return res;
184 }
185
186 static ir_node *ifg_std_neighbours_begin(const void *self, void *iter, const ir_node *irn)
187 {
188         adj_iter_t *it = iter;
189         find_neighbours(self, iter, irn);
190         return pset_first(it->neighbours);
191 }
192
193 static ir_node *ifg_std_neighbours_next(const void *self, void *iter)
194 {
195         return get_next_neighbour(iter);
196 }
197
198 static void ifg_std_neighbours_break(const void *self, void *iter)
199 {
200         neighbours_break(iter, 1);
201 }
202
203 static int ifg_std_degree(const void *self, const ir_node *irn)
204 {
205         adj_iter_t it;
206         int degree;
207         find_neighbours(self, &it, irn);
208         degree = pset_count(it.neighbours);
209         neighbours_break(&it, 1);
210         return degree;
211 }
212
213 static const be_ifg_impl_t ifg_std_impl = {
214         sizeof(nodes_iter_t),
215         sizeof(adj_iter_t),
216
217         ifg_std_free,
218         ifg_std_connected,
219         ifg_std_neighbours_begin,
220         ifg_std_neighbours_next,
221         ifg_std_neighbours_break,
222         ifg_std_nodes_begin,
223         ifg_std_nodes_next,
224         ifg_std_nodes_break,
225         ifg_std_degree
226 };
227
228 be_ifg_t *be_ifg_std_new(const be_chordal_env_t *env)
229 {
230         ifg_std_t *ifg = malloc(sizeof(*ifg));
231
232         ifg->impl = &ifg_std_impl;
233         ifg->env  = env;
234
235         return (be_ifg_t *) ifg;
236 }