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    case nir_intrinsic_interp_var_at_offset:
  61       shader->info.uses_interp_var_at_offset = 1;
  62       break;
  63
  64    default:
  65       break;
  66    }
  67 }
  68
  69 static void
  70 gather_tex_info(nir_tex_instr *instr, nir_shader *shader)
  71 {
  72    if (instr->op == nir_texop_tg4)
  73       shader->info.uses_texture_gather = true;
  74 }
  75
  76 static void
  77 gather_info_block(nir_block *block, nir_shader *shader)
  78 {
  79    nir_foreach_instr(instr, block) {
  80       switch (instr->type) {
  81       case nir_instr_type_intrinsic:
  82          gather_intrinsic_info(nir_instr_as_intrinsic(instr), shader);
  83          break;
  84       case nir_instr_type_tex:
  85          gather_tex_info(nir_instr_as_tex(instr), shader);
  86          break;
  87       case nir_instr_type_call:
  88          assert(!"nir_shader_gather_info only works if functions are inlined");
  89          break;
  90       default:
  91          break;
  92       }
  93    }
  94 }
  95
  96 /**
  97  * Returns the bits in the inputs_read, outputs_written, or
  98  * system_values_read bitfield corresponding to this variable.
  99  */
 100 static inline uint64_t
 101 get_io_mask(nir_variable *var, gl_shader_stage stage)
 102 {
 103    assert(var->data.mode == nir_var_shader_in ||
 104           var->data.mode == nir_var_shader_out ||
 105           var->data.mode == nir_var_system_value);
 106    assert(var->data.location >= 0);
 107
 108    const struct glsl_type *var_type = var->type;
 109    if (stage == MESA_SHADER_GEOMETRY && var->data.mode == nir_var_shader_in) {
 110       /* Most geometry shader inputs are per-vertex arrays */
 111       if (var->data.location >= VARYING_SLOT_VAR0)
 112          assert(glsl_type_is_array(var_type));
 113
 114       if (glsl_type_is_array(var_type))
 115          var_type = glsl_get_array_element(var_type);
 116    }
 117
 118    bool is_vertex_input = (var->data.mode == nir_var_shader_in &&
 119                            stage == MESA_SHADER_VERTEX);
 120    unsigned slots = glsl_count_attribute_slots(var_type, is_vertex_input);
 121    return ((1ull << slots) - 1) << var->data.location;
 122 }
 123
 124 void
 125 nir_shader_gather_info(nir_shader *shader, nir_function_impl *entrypoint)
 126 {
 127    /* This pass does not yet support tessellation shaders */
 128    assert(shader->stage == MESA_SHADER_VERTEX ||
 129           shader->stage == MESA_SHADER_GEOMETRY ||
 130           shader->stage == MESA_SHADER_FRAGMENT ||
 131           shader->stage == MESA_SHADER_COMPUTE);
 132
 133    bool uses_sample_qualifier = false;
 134    shader->info.inputs_read = 0;
 135    foreach_list_typed(nir_variable, var, node, &shader->inputs) {
 136       shader->info.inputs_read |= get_io_mask(var, shader->stage);
 137       uses_sample_qualifier |= var->data.sample;
 138    }
 139
 140    if (shader->stage == MESA_SHADER_FRAGMENT)
 141       shader->info.fs.uses_sample_qualifier = uses_sample_qualifier;
 142
 143    /* TODO: Some day we may need to add stream support to NIR */
 144    shader->info.outputs_written = 0;
 145    foreach_list_typed(nir_variable, var, node, &shader->outputs)
 146       shader->info.outputs_written |= get_io_mask(var, shader->stage);
 147
 148    shader->info.system_values_read = 0;
 149    foreach_list_typed(nir_variable, var, node, &shader->system_values)
 150       shader->info.system_values_read |= get_io_mask(var, shader->stage);
 151
 152    shader->info.num_textures = 0;
 153    shader->info.num_images = 0;
 154    nir_foreach_variable(var, &shader->uniforms) {
 155       const struct glsl_type *type = var->type;
 156       unsigned count = 1;
 157       if (glsl_type_is_array(type)) {
 158          count = glsl_get_length(type);
 159          type = glsl_get_array_element(type);
 160       }
 161
 162       if (glsl_type_is_image(type)) {
 163          shader->info.num_images += count;
 164       } else if (glsl_type_is_sampler(type)) {
 165          shader->info.num_textures += count;
 166       }
 167    }
 168
 169    nir_foreach_block(block, entrypoint) {
 170       gather_info_block(block, shader);
 171    }
 172 }