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_work_group_id:
  48    case nir_intrinsic_load_num_work_groups:
  49       shader->info.system_values_read |=
  50          (1 << nir_system_value_from_intrinsic(instr->intrinsic));
  51       break;
  52
  53    case nir_intrinsic_end_primitive:
  54    case nir_intrinsic_end_primitive_with_counter:
  55       assert(shader->stage == MESA_SHADER_GEOMETRY);
  56       shader->info.gs.uses_end_primitive = 1;
  57       break;
  58
  59    default:
  60       break;
  61    }
  62 }
  63
  64 static void
  65 gather_tex_info(nir_tex_instr *instr, nir_shader *shader)
  66 {
  67    if (instr->op == nir_texop_tg4)
  68       shader->info.uses_texture_gather = true;
  69 }
  70
  71 static void
  72 gather_info_block(nir_block *block, nir_shader *shader)
  73 {
  74    nir_foreach_instr(instr, block) {
  75       switch (instr->type) {
  76       case nir_instr_type_intrinsic:
  77          gather_intrinsic_info(nir_instr_as_intrinsic(instr), shader);
  78          break;
  79       case nir_instr_type_tex:
  80          gather_tex_info(nir_instr_as_tex(instr), shader);
  81          break;
  82       case nir_instr_type_call:
  83          assert(!"nir_shader_gather_info only works if functions are inlined");
  84          break;
  85       default:
  86          break;
  87       }
  88    }
  89 }
  90
  91 /**
  92  * Returns the bits in the inputs_read, outputs_written, or
  93  * system_values_read bitfield corresponding to this variable.
  94  */
  95 static inline uint64_t
  96 get_io_mask(nir_variable *var, gl_shader_stage stage)
  97 {
  98    assert(var->data.mode == nir_var_shader_in ||
  99           var->data.mode == nir_var_shader_out ||
 100           var->data.mode == nir_var_system_value);
 101    assert(var->data.location >= 0);
 102
 103    const struct glsl_type *var_type = var->type;
 104    if (stage == MESA_SHADER_GEOMETRY && var->data.mode == nir_var_shader_in) {
 105       /* Most geometry shader inputs are per-vertex arrays */
 106       if (var->data.location >= VARYING_SLOT_VAR0)
 107          assert(glsl_type_is_array(var_type));
 108
 109       if (glsl_type_is_array(var_type))
 110          var_type = glsl_get_array_element(var_type);
 111    }
 112
 113    bool is_vertex_input = (var->data.mode == nir_var_shader_in &&
 114                            stage == MESA_SHADER_VERTEX);
 115    unsigned slots = glsl_count_attribute_slots(var_type, is_vertex_input);
 116    return ((1ull << slots) - 1) << var->data.location;
 117 }
 118
 119 void
 120 nir_shader_gather_info(nir_shader *shader, nir_function_impl *entrypoint)
 121 {
 122    /* This pass does not yet support tessellation shaders */
 123    assert(shader->stage == MESA_SHADER_VERTEX ||
 124           shader->stage == MESA_SHADER_GEOMETRY ||
 125           shader->stage == MESA_SHADER_FRAGMENT ||
 126           shader->stage == MESA_SHADER_COMPUTE);
 127
 128    shader->info.inputs_read = 0;
 129    foreach_list_typed(nir_variable, var, node, &shader->inputs)
 130       shader->info.inputs_read |= get_io_mask(var, shader->stage);
 131
 132    /* TODO: Some day we may need to add stream support to NIR */
 133    shader->info.outputs_written = 0;
 134    foreach_list_typed(nir_variable, var, node, &shader->outputs)
 135       shader->info.outputs_written |= get_io_mask(var, shader->stage);
 136
 137    shader->info.system_values_read = 0;
 138    foreach_list_typed(nir_variable, var, node, &shader->system_values)
 139       shader->info.system_values_read |= get_io_mask(var, shader->stage);
 140
 141    shader->info.num_textures = 0;
 142    shader->info.num_images = 0;
 143    nir_foreach_variable(var, &shader->uniforms) {
 144       const struct glsl_type *type = var->type;
 145       unsigned count = 1;
 146       if (glsl_type_is_array(type)) {
 147          count = glsl_get_length(type);
 148          type = glsl_get_array_element(type);
 149       }
 150
 151       if (glsl_type_is_image(type)) {
 152          shader->info.num_images += count;
 153       } else if (glsl_type_is_sampler(type)) {
 154          shader->info.num_textures += count;
 155       }
 156    }
 157
 158    nir_foreach_block(block, entrypoint) {
 159       gather_info_block(block, shader);
 160    }
 161 }