xref: /aosp_15_r20/external/libdav1d/src/ctx.h (revision c09093415860a1c2373dacd84c4fde00c507cdfd)
1 /*
2  * Copyright © 2018, VideoLAN and dav1d authors
3  * Copyright © 2018, Two Orioles, LLC
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions are met:
8  *
9  * 1. Redistributions of source code must retain the above copyright notice, this
10  *    list of conditions and the following disclaimer.
11  *
12  * 2. Redistributions in binary form must reproduce the above copyright notice,
13  *    this list of conditions and the following disclaimer in the documentation
14  *    and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
19  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
23  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #ifndef DAV1D_SRC_CTX_H
29 #define DAV1D_SRC_CTX_H
30 
31 #include <stdint.h>
32 
33 #include "common/attributes.h"
34 #include "common/intops.h"
35 
36 union alias64 { uint64_t u64; uint8_t u8[8]; } ATTR_ALIAS;
37 union alias32 { uint32_t u32; uint8_t u8[4]; } ATTR_ALIAS;
38 union alias16 { uint16_t u16; uint8_t u8[2]; } ATTR_ALIAS;
39 union alias8 { uint8_t u8; } ATTR_ALIAS;
40 
41 typedef void (*dav1d_memset_pow2_fn)(void *ptr, int value);
42 EXTERN const dav1d_memset_pow2_fn dav1d_memset_pow2[6];
43 
dav1d_memset_likely_pow2(void * const ptr,const int value,const int n)44 static inline void dav1d_memset_likely_pow2(void *const ptr, const int value, const int n) {
45     assert(n >= 1 && n <= 32);
46     if ((n&(n-1)) == 0) {
47         dav1d_memset_pow2[ulog2(n)](ptr, value);
48     } else {
49         memset(ptr, value, n);
50     }
51 }
52 
53 // For smaller sizes use multiplication to broadcast bytes. memset misbehaves on the smaller sizes.
54 // For the larger sizes, we want to use memset to get access to vector operations.
55 #define set_ctx1(var, off, val) \
56     ((union alias8 *) &(var)[off])->u8 = (val) * 0x01
57 #define set_ctx2(var, off, val) \
58     ((union alias16 *) &(var)[off])->u16 = (val) * 0x0101
59 #define set_ctx4(var, off, val) \
60     ((union alias32 *) &(var)[off])->u32 = (val) * 0x01010101U
61 #define set_ctx8(var, off, val) \
62     ((union alias64 *) &(var)[off])->u64 = (val) * 0x0101010101010101ULL
63 #define set_ctx16(var, off, val) do { \
64         memset(&(var)[off], val, 16); \
65     } while (0)
66 #define set_ctx32(var, off, val) do { \
67         memset(&(var)[off], val, 32); \
68     } while (0)
69 #define case_set(var) \
70     switch (var) { \
71     case 0: set_ctx(set_ctx1); break; \
72     case 1: set_ctx(set_ctx2); break; \
73     case 2: set_ctx(set_ctx4); break; \
74     case 3: set_ctx(set_ctx8); break; \
75     case 4: set_ctx(set_ctx16); break; \
76     case 5: set_ctx(set_ctx32); break; \
77     default: assert(0); \
78     }
79 #define case_set_upto16(var) \
80     switch (var) { \
81     case 0: set_ctx(set_ctx1); break; \
82     case 1: set_ctx(set_ctx2); break; \
83     case 2: set_ctx(set_ctx4); break; \
84     case 3: set_ctx(set_ctx8); break; \
85     case 4: set_ctx(set_ctx16); break; \
86     default: assert(0); \
87     }
88 
89 #endif /* DAV1D_SRC_CTX_H */
90