1 /*
2 * Copyright © 2016 Red Hat
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 FROM,
20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 * SOFTWARE.
22 */
23
24 /* Lowers the additional tex_src_plane src, generated by nir_lower_tex
25 * for planar YUV textures, into separate samplers, matching the logic
26 * that mesa/st uses to insert additional sampler view/state (since both
27 * sides need to agree).
28 *
29 * This should run after nir_lower_samplers.
30 */
31
32 #include "compiler/nir/nir.h"
33 #include "st_nir.h"
34
35 typedef struct {
36 unsigned lower_2plane;
37 unsigned lower_3plane;
38
39 /* Maps a primary sampler (used for Y) to the U or UV sampler. In
40 * case of 3-plane YUV format, the V plane is next sampler after U.
41 */
42 unsigned char sampler_map[PIPE_MAX_SAMPLERS][2];
43 } lower_tex_src_state;
44
45 static void
assign_extra_samplers(lower_tex_src_state * state,unsigned free_slots)46 assign_extra_samplers(lower_tex_src_state *state, unsigned free_slots)
47 {
48 unsigned mask = state->lower_2plane | state->lower_3plane;
49
50 while (mask) {
51 unsigned extra, y_samp = u_bit_scan(&mask);
52
53 extra = u_bit_scan(&free_slots);
54 state->sampler_map[y_samp][0] = extra;
55
56 if (state->lower_3plane & (1 << y_samp)) {
57 extra = u_bit_scan(&free_slots);
58 state->sampler_map[y_samp][1] = extra;
59 }
60 }
61 }
62
63 static void
lower_tex_src_plane_block(lower_tex_src_state * state,nir_block * block)64 lower_tex_src_plane_block(lower_tex_src_state *state, nir_block *block)
65 {
66 nir_foreach_instr(instr, block) {
67 if (instr->type != nir_instr_type_tex)
68 continue;
69
70 nir_tex_instr *tex = nir_instr_as_tex(instr);
71 int plane_index = nir_tex_instr_src_index(tex, nir_tex_src_plane);
72
73 if (plane_index < 0)
74 continue;
75
76 nir_const_value *plane = nir_src_as_const_value(tex->src[plane_index].src);
77 assume(plane);
78
79 if (plane->i32[0] > 0) {
80 unsigned y_samp = tex->texture_index;
81
82 assume(tex->texture_index == tex->sampler_index);
83 assume(((state->lower_3plane & (1 << y_samp)) && plane->i32[0] < 3) ||
84 (plane->i32[0] < 2));
85
86 tex->texture_index = tex->sampler_index =
87 state->sampler_map[y_samp][plane->i32[0] - 1];
88 }
89
90 nir_tex_instr_remove_src(tex, plane_index);
91 }
92 }
93
94 static void
lower_tex_src_plane_impl(lower_tex_src_state * state,nir_function_impl * impl)95 lower_tex_src_plane_impl(lower_tex_src_state *state, nir_function_impl *impl)
96 {
97 nir_foreach_block(block, impl) {
98 lower_tex_src_plane_block(state, block);
99 }
100
101 nir_metadata_preserve(impl, nir_metadata_block_index |
102 nir_metadata_dominance);
103 }
104
105 void
st_nir_lower_tex_src_plane(struct nir_shader * shader,unsigned free_slots,unsigned lower_2plane,unsigned lower_3plane)106 st_nir_lower_tex_src_plane(struct nir_shader *shader, unsigned free_slots,
107 unsigned lower_2plane, unsigned lower_3plane)
108 {
109 lower_tex_src_state state = {0};
110
111 state.lower_2plane = lower_2plane;
112 state.lower_3plane = lower_3plane;
113
114 assign_extra_samplers(&state, free_slots);
115
116 nir_foreach_function(function, shader) {
117 if (function->impl)
118 lower_tex_src_plane_impl(&state, function->impl);
119 }
120 }
121