1 /*/
2 * Copyright 2013 VMware, Inc. All rights reserved.
3 *
4 * Permission is hereby granted, free of charge, to any person
5 * obtaining a copy of this software and associated documentation
6 * files (the "Software"), to deal in the Software without
7 * restriction, including without limitation the rights to use, copy,
8 * modify, merge, publish, distribute, sublicense, and/or sell copies
9 * of the Software, and to permit persons to whom the Software is
10 * furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be
13 * included in all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22 * SOFTWARE.
23 */
24
25
26 #include "svga_context.h"
27 #include "svga_link.h"
28 #include "svga_debug.h"
29
30 #include "tgsi/tgsi_strings.h"
31
32
33 #define INVALID_INDEX 255
34
35
36 /**
37 * Examine input and output shaders info to link outputs from the
38 * output shader to inputs from the input shader.
39 * Basically, we'll remap input shader's input slots to new numbers
40 * based on semantic name/index of the outputs from the output shader.
41 */
42 void
svga_link_shaders(const struct tgsi_shader_info * outshader_info,const struct tgsi_shader_info * inshader_info,struct shader_linkage * linkage)43 svga_link_shaders(const struct tgsi_shader_info *outshader_info,
44 const struct tgsi_shader_info *inshader_info,
45 struct shader_linkage *linkage)
46 {
47 unsigned i, free_slot;
48
49 for (i = 0; i < ARRAY_SIZE(linkage->input_map); i++) {
50 linkage->input_map[i] = INVALID_INDEX;
51 }
52
53 for (i = 0; i < ARRAY_SIZE(linkage->prevShader.output_map); i++) {
54 linkage->prevShader.output_map[i] = INVALID_INDEX;
55 }
56
57 /* Assign input slots for input shader inputs.
58 * Basically, we want to use the same index for the output shader's outputs
59 * and the input shader's inputs that should be linked together.
60 * We'll modify the input shader's inputs to match the output shader.
61 */
62 assert(inshader_info->num_inputs <=
63 ARRAY_SIZE(inshader_info->input_semantic_name));
64
65 /* free register index that can be used for built-in varyings */
66 free_slot = outshader_info->num_outputs + 1;
67
68 for (i = 0; i < inshader_info->num_inputs; i++) {
69 enum tgsi_semantic sem_name = inshader_info->input_semantic_name[i];
70 unsigned sem_index = inshader_info->input_semantic_index[i];
71 unsigned j;
72 unsigned out_index;
73
74 /* search output shader outputs for same item */
75 for (j = 0; j < outshader_info->num_outputs; j++) {
76 assert(j < ARRAY_SIZE(outshader_info->output_semantic_name));
77 if (outshader_info->output_semantic_name[j] == sem_name &&
78 outshader_info->output_semantic_index[j] == sem_index) {
79 linkage->input_map[i] = j;
80 linkage->prevShader.output_map[j] = i;
81 break;
82 }
83 }
84
85 /**
86 * The clip distance inputs come from the output shader's
87 * clip distance shadow copy, so mark the input index to match
88 * the index of the shadow copy.
89 */
90 if (sem_name == TGSI_SEMANTIC_CLIPDIST) {
91 out_index = outshader_info->num_outputs + 1 + sem_index;
92 linkage->input_map[i] = out_index;
93 linkage->prevShader.output_map[out_index] = i;
94 /* make sure free_slot includes this extra output */
95 free_slot = MAX2(free_slot, linkage->input_map[i] + 1);
96 }
97 }
98
99 /* Find the index for position */
100 linkage->position_index = 0;
101 for (i = 0; i < outshader_info->num_outputs; i++) {
102 if (outshader_info->output_semantic_name[i] == TGSI_SEMANTIC_POSITION) {
103 linkage->position_index = i;
104 break;
105 }
106 }
107
108 linkage->num_inputs = inshader_info->num_inputs;
109 linkage->prevShader.num_outputs = outshader_info->num_outputs;
110
111 /* Things like the front-face register are handled here */
112 for (i = 0; i < inshader_info->num_inputs; i++) {
113 if (linkage->input_map[i] == INVALID_INDEX) {
114 unsigned j = free_slot++;
115 linkage->input_map[i] = j;
116 linkage->prevShader.output_map[j] = i;
117 }
118 }
119 linkage->input_map_max = free_slot - 1;
120
121 /* Debug */
122 if (SVGA_DEBUG & DEBUG_TGSI) {
123 uint64_t reg = 0;
124 uint64_t one = 1;
125
126 debug_printf(
127 "### linkage info: num_inputs=%d input_map_max=%d prevShader.num_outputs=%d\n",
128 linkage->num_inputs, linkage->input_map_max,
129 linkage->prevShader.num_outputs);
130
131 for (i = 0; i < linkage->num_inputs; i++) {
132
133 assert(linkage->input_map[i] != INVALID_INDEX);
134
135 debug_printf(" input[%d] slot %u %s %u %s\n",
136 i,
137 linkage->input_map[i],
138 tgsi_semantic_names[inshader_info->input_semantic_name[i]],
139 inshader_info->input_semantic_index[i],
140 tgsi_interpolate_names[inshader_info->input_interpolate[i]]);
141
142 /* make sure no repeating register index */
143 assert((reg & (one << linkage->input_map[i])) == 0);
144 reg |= one << linkage->input_map[i];
145 }
146 }
147 }
148