1 /* 2 * Copyright 2015 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 #include "nir.h" 25 #include "nir_builder.h" 26 27 /* Lower glDrawPixels(). 28 * 29 * This is based on the logic in st_get_drawpix_shader() in TGSI compiler. 30 * 31 * Run before nir_lower_io. 32 */ 33 34 typedef struct { 35 const nir_lower_drawpixels_options *options; 36 nir_shader *shader; 37 nir_builder b; 38 nir_variable *texcoord, *scale, *bias; 39 } lower_drawpixels_state; 40 41 static nir_ssa_def * 42 get_texcoord(lower_drawpixels_state *state) 43 { 44 if (state->texcoord == NULL) { 45 nir_variable *texcoord = NULL; 46 47 /* find gl_TexCoord, if it exists: */ 48 nir_foreach_variable(var, &state->shader->inputs) { 49 if (var->data.location == VARYING_SLOT_TEX0) { 50 texcoord = var; 51 break; 52 } 53 } 54 55 /* otherwise create it: */ 56 if (texcoord == NULL) { 57 texcoord = nir_variable_create(state->shader, 58 nir_var_shader_in, 59 glsl_vec4_type(), 60 "gl_TexCoord"); 61 texcoord->data.location = VARYING_SLOT_TEX0; 62 } 63 64 state->texcoord = texcoord; 65 } 66 return nir_load_var(&state->b, state->texcoord); 67 } 68 69 static nir_variable * 70 create_uniform(nir_shader *shader, const char *name, const int state_tokens[5]) 71 { 72 nir_variable *var = nir_variable_create(shader, 73 nir_var_uniform, 74 glsl_vec4_type(), 75 name); 76 var->num_state_slots = 1; 77 var->state_slots = ralloc_array(var, nir_state_slot, 1); 78 memcpy(var->state_slots[0].tokens, state_tokens, 79 sizeof(var->state_slots[0].tokens)); 80 return var; 81 } 82 83 static nir_ssa_def * 84 get_scale(lower_drawpixels_state *state) 85 { 86 if (state->scale == NULL) { 87 state->scale = create_uniform(state->shader, "gl_PTscale", 88 state->options->scale_state_tokens); 89 } 90 return nir_load_var(&state->b, state->scale); 91 } 92 93 static nir_ssa_def * 94 get_bias(lower_drawpixels_state *state) 95 { 96 if (state->bias == NULL) { 97 state->bias = create_uniform(state->shader, "gl_PTbias", 98 state->options->bias_state_tokens); 99 } 100 return nir_load_var(&state->b, state->bias); 101 } 102 103 static nir_ssa_def * 104 get_texcoord_const(lower_drawpixels_state *state) 105 { 106 if (state->bias == NULL) { 107 state->bias = create_uniform(state->shader, "gl_MultiTexCoord0", 108 state->options->texcoord_state_tokens); 109 } 110 return nir_load_var(&state->b, state->bias); 111 } 112 113 static void 114 lower_color(lower_drawpixels_state *state, nir_intrinsic_instr *intr) 115 { 116 nir_builder *b = &state->b; 117 nir_ssa_def *texcoord; 118 nir_tex_instr *tex; 119 nir_ssa_def *def; 120 121 assert(intr->dest.is_ssa); 122 123 b->cursor = nir_before_instr(&intr->instr); 124 125 texcoord = get_texcoord(state); 126 127 /* replace load_var(gl_Color) w/ texture sample: 128 * TEX def, texcoord, drawpix_sampler, 2D 129 */ 130 tex = nir_tex_instr_create(state->shader, 1); 131 tex->op = nir_texop_tex; 132 tex->sampler_dim = GLSL_SAMPLER_DIM_2D; 133 tex->coord_components = 2; 134 tex->sampler_index = state->options->drawpix_sampler; 135 tex->texture_index = state->options->drawpix_sampler; 136 tex->dest_type = nir_type_float; 137 tex->src[0].src_type = nir_tex_src_coord; 138 tex->src[0].src = nir_src_for_ssa(texcoord); 139 140 nir_ssa_dest_init(&tex->instr, &tex->dest, 4, 32, NULL); 141 nir_builder_instr_insert(b, &tex->instr); 142 def = &tex->dest.ssa; 143 144 /* Apply the scale and bias. */ 145 if (state->options->scale_and_bias) { 146 /* MAD def, def, scale, bias; */ 147 def = nir_ffma(b, def, get_scale(state), get_bias(state)); 148 } 149 150 if (state->options->pixel_maps) { 151 static const unsigned swiz_xy[4] = {0,1}; 152 static const unsigned swiz_zw[4] = {2,3}; 153 154 /* do four pixel map look-ups with two TEX instructions: */ 155 nir_ssa_def *def_xy, *def_zw; 156 157 /* TEX def.xy, def.xyyy, pixelmap_sampler, 2D; */ 158 tex = nir_tex_instr_create(state->shader, 1); 159 tex->op = nir_texop_tex; 160 tex->sampler_dim = GLSL_SAMPLER_DIM_2D; 161 tex->coord_components = 2; 162 tex->sampler_index = state->options->pixelmap_sampler; 163 tex->texture_index = state->options->pixelmap_sampler; 164 tex->dest_type = nir_type_float; 165 tex->src[0].src_type = nir_tex_src_coord; 166 tex->src[0].src = nir_src_for_ssa(nir_swizzle(b, def, swiz_xy, 2, true)); 167 168 nir_ssa_dest_init(&tex->instr, &tex->dest, 4, 32, NULL); 169 nir_builder_instr_insert(b, &tex->instr); 170 def_xy = &tex->dest.ssa; 171 172 /* TEX def.zw, def.zwww, pixelmap_sampler, 2D; */ 173 tex = nir_tex_instr_create(state->shader, 1); 174 tex->op = nir_texop_tex; 175 tex->sampler_dim = GLSL_SAMPLER_DIM_2D; 176 tex->coord_components = 2; 177 tex->sampler_index = state->options->pixelmap_sampler; 178 tex->dest_type = nir_type_float; 179 tex->src[0].src_type = nir_tex_src_coord; 180 tex->src[0].src = nir_src_for_ssa(nir_swizzle(b, def, swiz_zw, 2, true)); 181 182 nir_ssa_dest_init(&tex->instr, &tex->dest, 4, 32, NULL); 183 nir_builder_instr_insert(b, &tex->instr); 184 def_zw = &tex->dest.ssa; 185 186 /* def = vec4(def.xy, def.zw); */ 187 def = nir_vec4(b, 188 nir_channel(b, def_xy, 0), 189 nir_channel(b, def_xy, 1), 190 nir_channel(b, def_zw, 0), 191 nir_channel(b, def_zw, 1)); 192 } 193 194 nir_ssa_def_rewrite_uses(&intr->dest.ssa, nir_src_for_ssa(def)); 195 } 196 197 static void 198 lower_texcoord(lower_drawpixels_state *state, nir_intrinsic_instr *intr) 199 { 200 state->b.cursor = nir_before_instr(&intr->instr); 201 202 nir_ssa_def *texcoord_const = get_texcoord_const(state); 203 nir_ssa_def_rewrite_uses(&intr->dest.ssa, nir_src_for_ssa(texcoord_const)); 204 } 205 206 static bool 207 lower_drawpixels_block(lower_drawpixels_state *state, nir_block *block) 208 { 209 nir_foreach_instr_safe(instr, block) { 210 if (instr->type == nir_instr_type_intrinsic) { 211 nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr); 212 if (intr->intrinsic == nir_intrinsic_load_var) { 213 nir_deref_var *dvar = intr->variables[0]; 214 nir_variable *var = dvar->var; 215 216 if (var->data.location == VARYING_SLOT_COL0) { 217 /* gl_Color should not have array/struct deref's: */ 218 assert(dvar->deref.child == NULL); 219 lower_color(state, intr); 220 } else if (var->data.location == VARYING_SLOT_TEX0) { 221 /* gl_TexCoord should not have array/struct deref's: */ 222 assert(dvar->deref.child == NULL); 223 lower_texcoord(state, intr); 224 } 225 } 226 } 227 } 228 229 return true; 230 } 231 232 static void 233 lower_drawpixels_impl(lower_drawpixels_state *state, nir_function_impl *impl) 234 { 235 nir_builder_init(&state->b, impl); 236 237 nir_foreach_block(block, impl) { 238 lower_drawpixels_block(state, block); 239 } 240 nir_metadata_preserve(impl, nir_metadata_block_index | 241 nir_metadata_dominance); 242 } 243 244 void 245 nir_lower_drawpixels(nir_shader *shader, 246 const nir_lower_drawpixels_options *options) 247 { 248 lower_drawpixels_state state = { 249 .options = options, 250 .shader = shader, 251 }; 252 253 assert(shader->stage == MESA_SHADER_FRAGMENT); 254 255 nir_foreach_function(function, shader) { 256 if (function->impl) 257 lower_drawpixels_impl(&state, function->impl); 258 } 259 } 260
