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 bool
  72 gather_info_block(nir_block *block, void *shader)
  73 {
  74    nir_foreach_instr(block, instr) {
  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    return true;
  91 }
  92
  93 /**
  94  * Returns the bits in the inputs_read, outputs_written, or
  95  * system_values_read bitfield corresponding to this variable.
  96  */
  97 static inline uint64_t
  98 get_io_mask(nir_variable *var, gl_shader_stage stage)
  99 {
 100    assert(var->data.mode == nir_var_shader_in ||
 101           var->data.mode == nir_var_shader_out ||
 102           var->data.mode == nir_var_system_value);
 103    assert(var->data.location >= 0);
 104
 105    const struct glsl_type *var_type = var->type;
 106    if (stage == MESA_SHADER_GEOMETRY && var->data.mode == nir_var_shader_in) {
 107       /* Most geometry shader inputs are per-vertex arrays */
 108       if (var->data.location >= VARYING_SLOT_VAR0)
 109          assert(glsl_type_is_array(var_type));
 110
 111       if (glsl_type_is_array(var_type))
 112          var_type = glsl_get_array_element(var_type);
 113    }
 114
 115    bool is_vertex_input = (var->data.mode == nir_var_shader_in &&
 116                            stage == MESA_SHADER_VERTEX);
 117    unsigned slots = glsl_count_attribute_slots(var_type, is_vertex_input);
 118    return ((1ull << slots) - 1) << var->data.location;
 119 }
 120
 121 void
 122 nir_shader_gather_info(nir_shader *shader, nir_function_impl *entrypoint)
 123 {
 124    /* This pass does not yet support tessellation shaders */
 125    assert(shader->stage == MESA_SHADER_VERTEX ||
 126           shader->stage == MESA_SHADER_GEOMETRY ||
 127           shader->stage == MESA_SHADER_FRAGMENT ||
 128           shader->stage == MESA_SHADER_COMPUTE);
 129
 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
 134    /* TODO: Some day we may need to add stream support to NIR */
 135    shader->info.outputs_written = 0;
 136    foreach_list_typed(nir_variable, var, node, &shader->outputs)
 137       shader->info.outputs_written |= get_io_mask(var, shader->stage);
 138
 139    shader->info.system_values_read = 0;
 140    foreach_list_typed(nir_variable, var, node, &shader->system_values)
 141       shader->info.system_values_read |= get_io_mask(var, shader->stage);
 142
 143    shader->info.num_textures = 0;
 144    shader->info.num_images = 0;
 145    nir_foreach_variable(var, &shader->uniforms) {
 146       const struct glsl_type *type = var->type;
 147       unsigned count = 1;
 148       if (glsl_type_is_array(type)) {
 149          count = glsl_get_length(type);
 150          type = glsl_get_array_element(type);
 151       }
 152
 153       if (glsl_type_is_image(type)) {
 154          shader->info.num_images += count;
 155       } else if (glsl_type_is_sampler(type)) {
 156          shader->info.num_textures += count;
 157       }
 158    }
 159
 160    nir_foreach_block(entrypoint, gather_info_block, shader);
 161 }