src/glsl/nir/nir_lower_samplers.cpp

   1 /*
   2  * Copyright (C) 2005-2007  Brian Paul   All Rights Reserved.
   3  * Copyright (C) 2008  VMware, Inc.   All Rights Reserved.
   4  * Copyright © 2014 Intel Corporation
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the "Software"),
   8  * to deal in the Software without restriction, including without limitation
   9  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  10  * and/or sell copies of the Software, and to permit persons to whom the
  11  * Software is furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice (including the next
  14  * paragraph) shall be included in all copies or substantial portions of the
  15  * Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  22  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  23  * DEALINGS IN THE SOFTWARE.
  24  */
  25
  26 #include "nir.h"
  27 #include "../program.h"
  28 #include "program/hash_table.h"
  29 #include "ir_uniform.h"
  30
  31 extern "C" {
  32 #include "main/compiler.h"
  33 #include "main/mtypes.h"
  34 #include "program/prog_parameter.h"
  35 #include "program/program.h"
  36 }
  37
  38 static void
  39 add_indirect_to_tex(nir_tex_instr *instr, nir_src indirect)
  40 {
  41    /* First, we have to resize the array of texture sources */
  42    nir_tex_src *new_srcs = rzalloc_array(instr, nir_tex_src,
  43                                          instr->num_srcs + 1);
  44
  45    for (unsigned i = 0; i < instr->num_srcs; i++) {
  46       new_srcs[i].src_type = instr->src[i].src_type;
  47       nir_instr_move_src(&instr->instr, &new_srcs[i].src, &instr->src[i].src);
  48    }
  49
  50    ralloc_free(instr->src);
  51    instr->src = new_srcs;
  52
  53    /* Now we can go ahead and move the source over to being a
  54     * first-class texture source.
  55     */
  56    instr->src[instr->num_srcs].src_type = nir_tex_src_sampler_offset;
  57    instr->num_srcs++;
  58    nir_instr_rewrite_src(&instr->instr, &instr->src[instr->num_srcs - 1].src,
  59                          indirect);
  60 }
  61
  62 static unsigned
  63 get_sampler_index(const struct gl_shader_program *shader_program,
  64                   gl_shader_stage stage, const char *name)
  65 {
  66    unsigned location;
  67    if (!shader_program->UniformHash->get(location, name)) {
  68       assert(!"failed to find sampler");
  69       return 0;
  70    }
  71
  72    if (!shader_program->UniformStorage[location].sampler[stage].active) {
  73       assert(!"cannot return a sampler");
  74       return 0;
  75    }
  76
  77    return shader_program->UniformStorage[location].sampler[stage].index;
  78 }
  79
  80 static void
  81 lower_sampler(nir_tex_instr *instr, const struct gl_shader_program *shader_program,
  82               gl_shader_stage stage, void *mem_ctx)
  83 {
  84    if (instr->sampler == NULL)
  85       return;
  86
  87    /* Get the name and the offset */
  88    instr->sampler_index = 0;
  89    char *name = ralloc_strdup(mem_ctx, instr->sampler->var->name);
  90
  91    for (nir_deref *deref = &instr->sampler->deref;
  92         deref->child; deref = deref->child) {
  93       switch (deref->child->deref_type) {
  94       case nir_deref_type_array: {
  95          nir_deref_array *deref_array = nir_deref_as_array(deref->child);
  96
  97          assert(deref_array->deref_array_type != nir_deref_array_type_wildcard);
  98
  99          if (deref_array->deref.child) {
 100             ralloc_asprintf_append(&name, "[%u]",
 101                deref_array->deref_array_type == nir_deref_array_type_direct ?
 102                   deref_array->base_offset : 0);
 103          } else {
 104             assert(deref->child->type->base_type == GLSL_TYPE_SAMPLER);
 105             instr->sampler_index = deref_array->base_offset;
 106          }
 107
 108          /* XXX: We're assuming here that the indirect is the last array
 109           * thing we have.  This should be ok for now as we don't support
 110           * arrays_of_arrays yet.
 111           */
 112          if (deref_array->deref_array_type == nir_deref_array_type_indirect) {
 113             /* First, we have to resize the array of texture sources */
 114             nir_tex_src *new_srcs = rzalloc_array(instr, nir_tex_src,
 115                                                   instr->num_srcs + 1);
 116
 117             for (unsigned i = 0; i < instr->num_srcs; i++) {
 118                new_srcs[i].src_type = instr->src[i].src_type;
 119                nir_instr_move_src(&instr->instr, &new_srcs[i].src,
 120                                   &instr->src[i].src);
 121             }
 122
 123             ralloc_free(instr->src);
 124             instr->src = new_srcs;
 125
 126             /* Now we can go ahead and move the source over to being a
 127              * first-class texture source.
 128              */
 129             instr->src[instr->num_srcs].src_type = nir_tex_src_sampler_offset;
 130             instr->num_srcs++;
 131             nir_instr_move_src(&instr->instr,
 132                                &instr->src[instr->num_srcs - 1].src,
 133                                &deref_array->indirect);
 134
 135             instr->sampler_array_size = glsl_get_length(deref->type);
 136          }
 137          break;
 138       }
 139
 140       case nir_deref_type_struct: {
 141          nir_deref_struct *deref_struct = nir_deref_as_struct(deref->child);
 142          const char *field = glsl_get_struct_elem_name(deref->type,
 143                                                        deref_struct->index);
 144          ralloc_asprintf_append(&name, ".%s", field);
 145          break;
 146       }
 147
 148       default:
 149          unreachable("Invalid deref type");
 150          break;
 151       }
 152    }
 153
 154    instr->sampler_index += get_sampler_index(shader_program, stage, name);
 155
 156    instr->sampler = NULL;
 157 }
 158
 159 typedef struct {
 160    void *mem_ctx;
 161    const struct gl_shader_program *shader_program;
 162    gl_shader_stage stage;
 163 } lower_state;
 164
 165 static bool
 166 lower_block_cb(nir_block *block, void *_state)
 167 {
 168    lower_state *state = (lower_state *) _state;
 169
 170    nir_foreach_instr(block, instr) {
 171       if (instr->type == nir_instr_type_tex) {
 172          nir_tex_instr *tex_instr = nir_instr_as_tex(instr);
 173          lower_sampler(tex_instr, state->shader_program, state->stage,
 174                        state->mem_ctx);
 175       }
 176    }
 177
 178    return true;
 179 }
 180
 181 static void
 182 lower_impl(nir_function_impl *impl, const struct gl_shader_program *shader_program,
 183            gl_shader_stage stage)
 184 {
 185    lower_state state;
 186
 187    state.mem_ctx = ralloc_parent(impl);
 188    state.shader_program = shader_program;
 189    state.stage = stage;
 190
 191    nir_foreach_block(impl, lower_block_cb, &state);
 192 }
 193
 194 extern "C" void
 195 nir_lower_samplers(nir_shader *shader,
 196                    const struct gl_shader_program *shader_program)
 197 {
 198    nir_foreach_overload(shader, overload) {
 199       if (overload->impl)
 200          lower_impl(overload->impl, shader_program, shader->stage);
 201    }
 202 }
 203
 204 static bool
 205 lower_samplers_for_vk_block(nir_block *block, void *data)
 206 {
 207    nir_foreach_instr(block, instr) {
 208       if (instr->type != nir_instr_type_tex)
 209          continue;
 210
 211       nir_tex_instr *tex = nir_instr_as_tex(instr);
 212
 213       assert(tex->sampler);
 214
 215       tex->sampler_set = tex->sampler->var->data.descriptor_set;
 216       tex->sampler_index = tex->sampler->var->data.binding;
 217
 218       if (tex->sampler->deref.child) {
 219          assert(tex->sampler->deref.child->deref_type == nir_deref_type_array);
 220          nir_deref_array *arr = nir_deref_as_array(tex->sampler->deref.child);
 221
 222          /* Only one-level arrays are allowed in vulkan */
 223          assert(arr->deref.child == NULL);
 224
 225          tex->sampler_index += arr->base_offset;
 226          if (arr->deref_array_type == nir_deref_array_type_indirect) {
 227             add_indirect_to_tex(tex, arr->indirect);
 228             nir_instr_rewrite_src(instr, &arr->indirect, NIR_SRC_INIT);
 229
 230             tex->sampler_array_size = glsl_get_length(tex->sampler->deref.type);
 231          }
 232       }
 233
 234       tex->sampler = NULL;
 235    }
 236
 237    return true;
 238 }
 239
 240 extern "C" void
 241 nir_lower_samplers_for_vk(nir_shader *shader)
 242 {
 243    nir_foreach_overload(shader, overload) {
 244       if (overload->impl) {
 245          nir_foreach_block(overload->impl, lower_samplers_for_vk_block, NULL);
 246       }
 247    }
 248 }