src/compiler/nir/nir_gather_info.c

   1 /*
   2  * Copyright © 2015 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 (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
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  21  * IN THE SOFTWARE.
  22  */
  23
  24 #include "nir.h"
  25
  26 static void
  27 gather_intrinsic_info(nir_intrinsic_instr *instr, nir_shader *shader)
  28 {
  29    switch (instr->intrinsic) {
  30    case nir_intrinsic_discard:
  31    case nir_intrinsic_discard_if:
  32       assert(shader->stage == MESA_SHADER_FRAGMENT);
  33       shader->info->fs.uses_discard = true;
  34       break;
  35
  36    case nir_intrinsic_load_front_face:
  37    case nir_intrinsic_load_vertex_id:
  38    case nir_intrinsic_load_vertex_id_zero_base:
  39    case nir_intrinsic_load_base_vertex:
  40    case nir_intrinsic_load_instance_id:
  41    case nir_intrinsic_load_sample_id:
  42    case nir_intrinsic_load_sample_pos:
  43    case nir_intrinsic_load_sample_mask_in:
  44    case nir_intrinsic_load_primitive_id:
  45    case nir_intrinsic_load_invocation_id:
  46    case nir_intrinsic_load_local_invocation_id:
  47    case nir_intrinsic_load_local_invocation_index:
  48    case nir_intrinsic_load_work_group_id:
  49    case nir_intrinsic_load_num_work_groups:
  50       shader->info->system_values_read |=
  51          (1 << nir_system_value_from_intrinsic(instr->intrinsic));
  52       break;
  53
  54    case nir_intrinsic_end_primitive:
  55    case nir_intrinsic_end_primitive_with_counter:
  56       assert(shader->stage == MESA_SHADER_GEOMETRY);
  57       shader->info->gs.uses_end_primitive = 1;
  58       break;
  59
  60    default:
  61       break;
  62    }
  63 }
  64
  65 static void
  66 gather_tex_info(nir_tex_instr *instr, nir_shader *shader)
  67 {
  68    if (instr->op == nir_texop_tg4)
  69       shader->info->uses_texture_gather = true;
  70 }
  71
  72 static void
  73 gather_info_block(nir_block *block, nir_shader *shader)
  74 {
  75    nir_foreach_instr(instr, block) {
  76       switch (instr->type) {
  77       case nir_instr_type_intrinsic:
  78          gather_intrinsic_info(nir_instr_as_intrinsic(instr), shader);
  79          break;
  80       case nir_instr_type_tex:
  81          gather_tex_info(nir_instr_as_tex(instr), shader);
  82          break;
  83       case nir_instr_type_call:
  84          assert(!"nir_shader_gather_info only works if functions are inlined");
  85          break;
  86       default:
  87          break;
  88       }
  89    }
  90 }
  91
  92 /**
  93  * Returns the bits in the inputs_read, outputs_written, or
  94  * system_values_read bitfield corresponding to this variable.
  95  */
  96 static inline uint64_t
  97 get_io_mask(nir_variable *var, gl_shader_stage stage)
  98 {
  99    assert(var->data.mode == nir_var_shader_in ||
 100           var->data.mode == nir_var_shader_out ||
 101           var->data.mode == nir_var_system_value);
 102    assert(var->data.location >= 0);
 103
 104    const struct glsl_type *var_type = var->type;
 105    if (stage == MESA_SHADER_GEOMETRY && var->data.mode == nir_var_shader_in) {
 106       /* Most geometry shader inputs are per-vertex arrays */
 107       if (var->data.location >= VARYING_SLOT_VAR0)
 108          assert(glsl_type_is_array(var_type));
 109
 110       if (glsl_type_is_array(var_type))
 111          var_type = glsl_get_array_element(var_type);
 112    }
 113
 114    bool is_vertex_input = (var->data.mode == nir_var_shader_in &&
 115                            stage == MESA_SHADER_VERTEX);
 116    unsigned slots = glsl_count_attribute_slots(var_type, is_vertex_input);
 117    return ((1ull << slots) - 1) << var->data.location;
 118 }
 119
 120 void
 121 nir_shader_gather_info(nir_shader *shader, nir_function_impl *entrypoint)
 122 {
 123    /* This pass does not yet support tessellation shaders */
 124    assert(shader->stage == MESA_SHADER_VERTEX ||
 125           shader->stage == MESA_SHADER_GEOMETRY ||
 126           shader->stage == MESA_SHADER_FRAGMENT ||
 127           shader->stage == MESA_SHADER_COMPUTE);
 128
 129    bool uses_sample_qualifier = false;
 130    shader->info->inputs_read = 0;
 131    foreach_list_typed(nir_variable, var, node, &shader->inputs) {
 132       shader->info->inputs_read |= get_io_mask(var, shader->stage);
 133       uses_sample_qualifier |= var->data.sample;
 134    }
 135
 136    if (shader->stage == MESA_SHADER_FRAGMENT)
 137       shader->info->fs.uses_sample_qualifier = uses_sample_qualifier;
 138
 139    /* TODO: Some day we may need to add stream support to NIR */
 140    shader->info->outputs_written = 0;
 141    foreach_list_typed(nir_variable, var, node, &shader->outputs)
 142       shader->info->outputs_written |= get_io_mask(var, shader->stage);
 143
 144    shader->info->system_values_read = 0;
 145    foreach_list_typed(nir_variable, var, node, &shader->system_values)
 146       shader->info->system_values_read |= get_io_mask(var, shader->stage);
 147
 148    shader->info->num_textures = 0;
 149    shader->info->num_images = 0;
 150    nir_foreach_variable(var, &shader->uniforms) {
 151       const struct glsl_type *type = var->type;
 152       unsigned count = 1;
 153       if (glsl_type_is_array(type)) {
 154          count = glsl_get_length(type);
 155          type = glsl_get_array_element(type);
 156       }
 157
 158       if (glsl_type_is_image(type)) {
 159          shader->info->num_images += count;
 160       } else if (glsl_type_is_sampler(type)) {
 161          shader->info->num_textures += count;
 162       }
 163    }
 164
 165    nir_foreach_block(block, entrypoint) {
 166       gather_info_block(block, shader);
 167    }
 168 }