1/*
2 * Copyright © 2018 Intel 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 shall be included
12 * in all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
15 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
17 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
19 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
20 * DEALINGS IN THE SOFTWARE.
21 */
22
23#include "tgsi/tgsi_from_mesa.h"
24#include "st_nir.h"
25#include "st_program.h"
26
27#include "compiler/nir/nir_builder.h"
28#include "compiler/glsl/gl_nir.h"
29#include "compiler/glsl/gl_nir_linker.h"
30#include "tgsi/tgsi_parse.h"
31
32struct pipe_shader_state *
33st_nir_finish_builtin_shader(struct st_context *st,
34                             nir_shader *nir)
35{
36   struct pipe_screen *screen = st->screen;
37   gl_shader_stage stage = nir->info.stage;
38
39   nir->info.separate_shader = true;
40   if (stage == MESA_SHADER_FRAGMENT)
41      nir->info.fs.untyped_color_outputs = true;
42
43   NIR_PASS_V(nir, nir_lower_global_vars_to_local);
44   NIR_PASS_V(nir, nir_split_var_copies);
45   NIR_PASS_V(nir, nir_lower_var_copies);
46   NIR_PASS_V(nir, nir_lower_system_values);
47   NIR_PASS_V(nir, nir_lower_compute_system_values, NULL);
48
49   if (nir->options->lower_to_scalar) {
50      nir_variable_mode mask =
51          (stage > MESA_SHADER_VERTEX ? nir_var_shader_in : 0) |
52          (stage < MESA_SHADER_FRAGMENT ? nir_var_shader_out : 0);
53
54      NIR_PASS_V(nir, nir_lower_io_to_scalar_early, mask);
55   }
56
57   if (st->lower_rect_tex) {
58      const struct nir_lower_tex_options opts = { .lower_rect = true, };
59      NIR_PASS_V(nir, nir_lower_tex, &opts);
60   }
61
62   nir_shader_gather_info(nir, nir_shader_get_entrypoint(nir));
63
64   st_nir_assign_vs_in_locations(nir);
65   st_nir_assign_varying_locations(st, nir);
66
67   st_nir_lower_samplers(screen, nir, NULL, NULL);
68   st_nir_lower_uniforms(st, nir);
69   if (!screen->get_param(screen, PIPE_CAP_NIR_IMAGES_AS_DEREF))
70      NIR_PASS_V(nir, gl_nir_lower_images, false);
71
72   if (screen->finalize_nir) {
73      char *msg = screen->finalize_nir(screen, nir);
74      free(msg);
75   } else {
76      gl_nir_opts(nir);
77   }
78
79   struct pipe_shader_state state = {
80      .type = PIPE_SHADER_IR_NIR,
81      .ir.nir = nir,
82   };
83
84   return st_create_nir_shader(st, &state);
85}
86
87/**
88 * Make a simple shader that copies inputs to corresponding outputs.
89 */
90struct pipe_shader_state *
91st_nir_make_passthrough_shader(struct st_context *st,
92                               const char *shader_name,
93                               gl_shader_stage stage,
94                               unsigned num_vars,
95                               unsigned *input_locations,
96                               unsigned *output_locations,
97                               unsigned *interpolation_modes,
98                               unsigned sysval_mask)
99{
100   const struct glsl_type *vec4 = glsl_vec4_type();
101   const nir_shader_compiler_options *options =
102      st_get_nir_compiler_options(st, stage);
103
104   nir_builder b = nir_builder_init_simple_shader(stage, options,
105                                                  "%s", shader_name);
106
107   char var_name[15];
108
109   for (unsigned i = 0; i < num_vars; i++) {
110      nir_variable *in;
111      if (sysval_mask & (1 << i)) {
112         snprintf(var_name, sizeof(var_name), "sys_%u", input_locations[i]);
113         in = nir_variable_create(b.shader, nir_var_system_value,
114                                  glsl_int_type(), var_name);
115      } else {
116         snprintf(var_name, sizeof(var_name), "in_%u", input_locations[i]);
117         in = nir_variable_create(b.shader, nir_var_shader_in, vec4, var_name);
118      }
119      in->data.location = input_locations[i];
120      if (interpolation_modes)
121         in->data.interpolation = interpolation_modes[i];
122
123      snprintf(var_name, sizeof(var_name), "out_%u", output_locations[i]);
124      nir_variable *out =
125         nir_variable_create(b.shader, nir_var_shader_out, in->type, var_name);
126      out->data.location = output_locations[i];
127      out->data.interpolation = in->data.interpolation;
128
129      nir_copy_var(&b, out, in);
130   }
131
132   return st_nir_finish_builtin_shader(st, b.shader);
133}
134
135/**
136 * Make a simple shader that reads color value from a constant buffer
137 * and uses it to clear all color buffers.
138 */
139struct pipe_shader_state *
140st_nir_make_clearcolor_shader(struct st_context *st)
141{
142   const nir_shader_compiler_options *options =
143      st_get_nir_compiler_options(st, MESA_SHADER_FRAGMENT);
144
145   nir_builder b = nir_builder_init_simple_shader(MESA_SHADER_FRAGMENT, options,
146                                                  "clear color FS");
147   b.shader->info.num_ubos = 1;
148   b.shader->num_outputs = 1;
149   b.shader->num_uniforms = 1;
150
151   /* Read clear color from constant buffer */
152   nir_ssa_def *clear_color = nir_load_uniform(&b, 4, 32, nir_imm_int(&b,0),
153                                               .range = 16,
154                                               .dest_type = nir_type_float32);
155
156   nir_variable *color_out =
157      nir_variable_create(b.shader, nir_var_shader_out, glsl_vec_type(4),
158                             "outcolor");
159   color_out->data.location = FRAG_RESULT_COLOR;
160
161   /* Write out the color */
162   nir_store_var(&b, color_out, clear_color, 0xf);
163
164   return st_nir_finish_builtin_shader(st, b.shader);
165}
166