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       assert(shader->stage == MESA_SHADER_FRAGMENT);
  32       shader->info.fs.uses_discard = true;
  33       break;
  34
  35    case nir_intrinsic_load_front_face:
  36    case nir_intrinsic_load_vertex_id:
  37    case nir_intrinsic_load_vertex_id_zero_base:
  38    case nir_intrinsic_load_base_vertex:
  39    case nir_intrinsic_load_instance_id:
  40    case nir_intrinsic_load_sample_id:
  41    case nir_intrinsic_load_sample_pos:
  42    case nir_intrinsic_load_sample_mask_in:
  43    case nir_intrinsic_load_primitive_id:
  44    case nir_intrinsic_load_invocation_id:
  45    case nir_intrinsic_load_local_invocation_id:
  46    case nir_intrinsic_load_work_group_id:
  47    case nir_intrinsic_load_num_work_groups:
  48       shader->info.system_values_read |=
  49          (1 << nir_system_value_from_intrinsic(instr->intrinsic));
  50       break;
  51
  52    case nir_intrinsic_end_primitive:
  53    case nir_intrinsic_end_primitive_with_counter:
  54       assert(shader->stage == MESA_SHADER_GEOMETRY);
  55       shader->info.gs.uses_end_primitive = 1;
  56       break;
  57
  58    default:
  59       break;
  60    }
  61 }
  62
  63 static void
  64 gather_tex_info(nir_tex_instr *instr, nir_shader *shader)
  65 {
  66    if (instr->op == nir_texop_tg4)
  67       shader->info.uses_texture_gather = true;
  68 }
  69
  70 static bool
  71 gather_info_block(nir_block *block, void *shader)
  72 {
  73    nir_foreach_instr(block, instr) {
  74       switch (instr->type) {
  75       case nir_instr_type_intrinsic:
  76          gather_intrinsic_info(nir_instr_as_intrinsic(instr), shader);
  77          break;
  78       case nir_instr_type_tex:
  79          gather_tex_info(nir_instr_as_tex(instr), shader);
  80          break;
  81       case nir_instr_type_call:
  82          assert(!"nir_shader_gather_info only works if functions are inlined");
  83          break;
  84       default:
  85          break;
  86       }
  87    }
  88
  89    return true;
  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    shader->info.inputs_read = 0;
 130    foreach_list_typed(nir_variable, var, node, &shader->inputs)
 131       shader->info.inputs_read |= get_io_mask(var, shader->stage);
 132
 133    /* TODO: Some day we may need to add stream support to NIR */
 134    shader->info.outputs_written = 0;
 135    foreach_list_typed(nir_variable, var, node, &shader->outputs)
 136       shader->info.outputs_written |= get_io_mask(var, shader->stage);
 137
 138    shader->info.system_values_read = 0;
 139    foreach_list_typed(nir_variable, var, node, &shader->system_values)
 140       shader->info.system_values_read |= get_io_mask(var, shader->stage);
 141
 142    shader->info.num_textures = 0;
 143    shader->info.num_images = 0;
 144    nir_foreach_variable(var, &shader->uniforms) {
 145       const struct glsl_type *type = var->type;
 146       unsigned count = 1;
 147       if (glsl_type_is_array(type)) {
 148          count = glsl_get_length(type);
 149          type = glsl_get_array_element(type);
 150       }
 151
 152       if (glsl_type_is_image(type)) {
 153          shader->info.num_images += count;
 154       } else if (glsl_type_is_sampler(type)) {
 155          shader->info.num_textures += count;
 156       }
 157    }
 158
 159    nir_foreach_block(entrypoint, gather_info_block, shader);
 160 }