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 /* Assign input slots for input shader inputs.
54 * Basically, we want to use the same index for the output shader's outputs
55 * and the input shader's inputs that should be linked together.
56 * We'll modify the input shader's inputs to match the output shader.
57 */
58 assert(inshader_info->num_inputs <=
59 ARRAY_SIZE(inshader_info->input_semantic_name));
60
61 /* free register index that can be used for built-in varyings */
62 free_slot = outshader_info->num_outputs + 1;
63
64 for (i = 0; i < inshader_info->num_inputs; i++) {
65 unsigned sem_name = inshader_info->input_semantic_name[i];
66 unsigned sem_index = inshader_info->input_semantic_index[i];
67 unsigned j;
68 /**
69 * Get the clip distance inputs from the output shader's
70 * clip distance shadow copy.
71 */
72 if (sem_name == TGSI_SEMANTIC_CLIPDIST) {
73 linkage->input_map[i] = outshader_info->num_outputs + 1 + sem_index;
74 /* make sure free_slot includes this extra output */
75 free_slot = MAX2(free_slot, linkage->input_map[i] + 1);
76 }
77 else {
78 /* search output shader outputs for same item */
79 for (j = 0; j < outshader_info->num_outputs; j++) {
80 assert(j < ARRAY_SIZE(outshader_info->output_semantic_name));
81 if (outshader_info->output_semantic_name[j] == sem_name &&
82 outshader_info->output_semantic_index[j] == sem_index) {
83 linkage->input_map[i] = j;
84 break;
85 }
86 }
87 }
88 }
89
90 linkage->num_inputs = inshader_info->num_inputs;
91
92 /* Things like the front-face register are handled here */
93 for (i = 0; i < inshader_info->num_inputs; i++) {
94 if (linkage->input_map[i] == INVALID_INDEX) {
95 unsigned j = free_slot++;
96 linkage->input_map[i] = j;
97 }
98 }
99
100 /* Debug */
101 if (SVGA_DEBUG & DEBUG_TGSI) {
102 unsigned reg = 0;
103 debug_printf("### linkage info:\n");
104
105 for (i = 0; i < linkage->num_inputs; i++) {
106
107 assert(linkage->input_map[i] != INVALID_INDEX);
108
109 debug_printf(" input[%d] slot %u %s %u %s\n",
110 i,
111 linkage->input_map[i],
112 tgsi_semantic_names[inshader_info->input_semantic_name[i]],
113 inshader_info->input_semantic_index[i],
114 tgsi_interpolate_names[inshader_info->input_interpolate[i]]);
115
116 /* make sure no repeating register index */
117 if (reg & 1 << linkage->input_map[i]) {
118 assert(0);
119 }
120 reg |= 1 << linkage->input_map[i];
121 }
122 }
123 }
124