1 /*
2 * Copyright (c) 2022 Collabora Ltd.
3 * Copyright © 2014 Intel Corporation
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice (including the next
13 * paragraph) shall be included in all copies or substantial portions of the
14 * Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
21 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
22 * IN THE SOFTWARE.
23 */
24
25
26 #ifndef _U_WORKLIST_
27 #define _U_WORKLIST_
28
29 #include "util/bitset.h"
30
31 #ifdef __cplusplus
32 extern "C" {
33 #endif
34
35 /** Represents a double-ended queue of unique entries. Each entry must have a
36 * unique index in the range [0, num_entries). Internally, entries are tracked
37 * as pointers to that index (so you can go from the index pointer back to a
38 * containing structure). This requires index pointers to remain valid while
39 * they are in the worklist (i.e. no realloc).
40 *
41 * The worklist data structure guarantees that each entry is in the queue at
42 * most once. Pushing an entry onto either end of the queue is a no-op if the
43 * entry is already in the queue. Internally, the data structure maintains a
44 * bitset of present entries.
45 */
46 typedef struct {
47 /* The total size of the worklist */
48 unsigned size;
49
50 /* The number of entries currently in the worklist */
51 unsigned count;
52
53 /* The offset in the array of entries at which the list starts */
54 unsigned start;
55
56 /* A bitset of all of the entries currently present in the worklist */
57 BITSET_WORD *present;
58
59 /* The actual worklist */
60 unsigned **entries;
61 } u_worklist;
62
63 void u_worklist_init(u_worklist *w, unsigned num_entries, void *mem_ctx);
64
65 void u_worklist_fini(u_worklist *w);
66
67 static inline bool
u_worklist_is_empty(const u_worklist * w)68 u_worklist_is_empty(const u_worklist *w)
69 {
70 return w->count == 0;
71 }
72
73 void u_worklist_push_head_index(u_worklist *w, unsigned *block);
74
75 unsigned *u_worklist_peek_head_index(const u_worklist *w);
76
77 unsigned *u_worklist_pop_head_index(u_worklist *w);
78
79 unsigned *u_worklist_peek_tail_index(const u_worklist *w);
80
81 void u_worklist_push_tail_index(u_worklist *w, unsigned *block);
82
83 unsigned *u_worklist_pop_tail_index(u_worklist *w);
84
85 #define u_worklist_push_tail(w, block, index) \
86 u_worklist_push_tail_index(w, &((block)->index))
87
88 #define u_worklist_push_head(w, block, index) \
89 u_worklist_push_head_index(w, &((block)->index))
90
91 #define u_worklist_pop_head(w, entry_t, index) \
92 container_of(u_worklist_pop_head_index(w), entry_t, index)
93
94 #define u_worklist_pop_tail(w, entry_t, index) \
95 container_of(u_worklist_pop_tail_index(w), entry_t, index)
96
97 #define u_worklist_peek_head(w, entry_t, index) \
98 container_of(u_worklist_peek_head_index(w), entry_t, index)
99
100 #define u_worklist_peek_tail(w, entry_t, index) \
101 container_of(u_worklist_peek_tail_index(w), entry_t, index)
102
103 #ifdef __cplusplus
104 } /* extern "C" */
105 #endif
106
107 #endif /* _U_WORKLIST_ */
108