1 /*
2 * Copyright © Microsoft Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 */
23
24 #include "dxil_buffer.h"
25 #include <assert.h>
26
27 void
dxil_buffer_init(struct dxil_buffer * b,unsigned abbrev_width)28 dxil_buffer_init(struct dxil_buffer *b, unsigned abbrev_width)
29 {
30 blob_init(&b->blob);
31 b->buf = 0;
32 b->buf_bits = 0;
33
34 b->abbrev_width = abbrev_width;
35 }
36
37 void
dxil_buffer_finish(struct dxil_buffer * b)38 dxil_buffer_finish(struct dxil_buffer *b)
39 {
40 blob_finish(&b->blob);
41 }
42
43 static bool
flush_dword(struct dxil_buffer * b)44 flush_dword(struct dxil_buffer *b)
45 {
46 assert(b->buf_bits >= 32 && b->buf_bits < 64);
47
48 uint32_t lower_bits = b->buf & UINT32_MAX;
49 if (!blob_write_bytes(&b->blob, &lower_bits, sizeof(lower_bits)))
50 return false;
51
52 b->buf >>= 32;
53 b->buf_bits -= 32;
54
55 return true;
56 }
57
58 bool
dxil_buffer_emit_bits(struct dxil_buffer * b,uint32_t data,unsigned width)59 dxil_buffer_emit_bits(struct dxil_buffer *b, uint32_t data, unsigned width)
60 {
61 assert(b->buf_bits < 32);
62 assert(width > 0 && width <= 32);
63 assert((data & ~((UINT64_C(1) << width) - 1)) == 0);
64
65 b->buf |= ((uint64_t)data) << b->buf_bits;
66 b->buf_bits += width;
67
68 if (b->buf_bits >= 32)
69 return flush_dword(b);
70
71 return true;
72 }
73
74 bool
dxil_buffer_emit_vbr_bits(struct dxil_buffer * b,uint64_t data,unsigned width)75 dxil_buffer_emit_vbr_bits(struct dxil_buffer *b, uint64_t data,
76 unsigned width)
77 {
78 assert(width > 1 && width <= 32);
79
80 uint32_t tag = UINT32_C(1) << (width - 1);
81 uint32_t max = tag - 1;
82 while (data > max) {
83 uint32_t value = (data & max) | tag;
84 data >>= width - 1;
85
86 if (!dxil_buffer_emit_bits(b, value, width))
87 return false;
88 }
89
90 return dxil_buffer_emit_bits(b, data, width);
91 }
92
93 bool
dxil_buffer_align(struct dxil_buffer * b)94 dxil_buffer_align(struct dxil_buffer *b)
95 {
96 assert(b->buf_bits < 32);
97
98 if (b->buf_bits) {
99 b->buf_bits = 32;
100 return flush_dword(b);
101 }
102
103 return true;
104 }
105