src/mesa/drivers/dri/i965/brw_nir.c

   1 /*
   2  * Copyright © 2014 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 "brw_nir.h"
  25 #include "glsl/glsl_parser_extras.h"
  26 #include "glsl/nir/glsl_to_nir.h"
  27 #include "program/prog_to_nir.h"
  28
  29 static void
  30 nir_optimize(nir_shader *nir)
  31 {
  32    bool progress;
  33    do {
  34       progress = false;
  35       nir_lower_vars_to_ssa(nir);
  36       nir_validate_shader(nir);
  37       nir_lower_alu_to_scalar(nir);
  38       nir_validate_shader(nir);
  39       progress |= nir_copy_prop(nir);
  40       nir_validate_shader(nir);
  41       nir_lower_phis_to_scalar(nir);
  42       nir_validate_shader(nir);
  43       progress |= nir_copy_prop(nir);
  44       nir_validate_shader(nir);
  45       progress |= nir_opt_dce(nir);
  46       nir_validate_shader(nir);
  47       progress |= nir_opt_cse(nir);
  48       nir_validate_shader(nir);
  49       progress |= nir_opt_peephole_select(nir);
  50       nir_validate_shader(nir);
  51       progress |= nir_opt_algebraic(nir);
  52       nir_validate_shader(nir);
  53       progress |= nir_opt_constant_folding(nir);
  54       nir_validate_shader(nir);
  55       progress |= nir_opt_remove_phis(nir);
  56       nir_validate_shader(nir);
  57    } while (progress);
  58 }
  59
  60 nir_shader *
  61 brw_create_nir(struct brw_context *brw,
  62                const struct gl_shader_program *shader_prog,
  63                const struct gl_program *prog,
  64                gl_shader_stage stage,
  65                bool is_scalar)
  66 {
  67    struct gl_context *ctx = &brw->ctx;
  68    const nir_shader_compiler_options *options =
  69       ctx->Const.ShaderCompilerOptions[stage].NirOptions;
  70    struct gl_shader *shader = shader_prog ? shader_prog->_LinkedShaders[stage] : NULL;
  71    bool debug_enabled = INTEL_DEBUG & intel_debug_flag_for_shader_stage(stage);
  72    nir_shader *nir;
  73
  74    /* First, lower the GLSL IR or Mesa IR to NIR */
  75    if (shader_prog) {
  76       nir = glsl_to_nir(shader, options);
  77    } else {
  78       nir = prog_to_nir(prog, options);
  79       nir_convert_to_ssa(nir); /* turn registers into SSA */
  80    }
  81    nir_validate_shader(nir);
  82
  83    nir_lower_global_vars_to_local(nir);
  84    nir_validate_shader(nir);
  85
  86    nir_lower_tex_projector(nir);
  87    nir_validate_shader(nir);
  88
  89    nir_normalize_cubemap_coords(nir);
  90    nir_validate_shader(nir);
  91
  92    nir_split_var_copies(nir);
  93    nir_validate_shader(nir);
  94
  95    nir_optimize(nir);
  96
  97    /* Lower a bunch of stuff */
  98    nir_lower_var_copies(nir);
  99    nir_validate_shader(nir);
 100
 101    /* Get rid of split copies */
 102    nir_optimize(nir);
 103
 104    nir_assign_var_locations_scalar_direct_first(nir, &nir->uniforms,
 105                                                 &nir->num_direct_uniforms,
 106                                                 &nir->num_uniforms);
 107    nir_assign_var_locations_scalar(&nir->inputs, &nir->num_inputs);
 108    nir_assign_var_locations_scalar(&nir->outputs, &nir->num_outputs);
 109
 110    nir_lower_io(nir);
 111    nir_validate_shader(nir);
 112
 113    nir_remove_dead_variables(nir);
 114    nir_validate_shader(nir);
 115
 116    if (shader_prog) {
 117       nir_lower_samplers(nir, shader_prog, stage);
 118       nir_validate_shader(nir);
 119    }
 120
 121    nir_lower_system_values(nir);
 122    nir_validate_shader(nir);
 123
 124    nir_lower_atomics(nir);
 125    nir_validate_shader(nir);
 126
 127    nir_optimize(nir);
 128
 129    if (brw->gen >= 6) {
 130       /* Try and fuse multiply-adds */
 131       nir_opt_peephole_ffma(nir);
 132       nir_validate_shader(nir);
 133    }
 134
 135    nir_opt_algebraic_late(nir);
 136    nir_validate_shader(nir);
 137
 138    nir_lower_locals_to_regs(nir);
 139    nir_validate_shader(nir);
 140
 141    nir_lower_to_source_mods(nir);
 142    nir_validate_shader(nir);
 143    nir_copy_prop(nir);
 144    nir_validate_shader(nir);
 145    nir_opt_dce(nir);
 146    nir_validate_shader(nir);
 147
 148    if (unlikely(debug_enabled)) {
 149       /* Re-index SSA defs so we print more sensible numbers. */
 150       nir_foreach_overload(nir, overload) {
 151          if (overload->impl)
 152             nir_index_ssa_defs(overload->impl);
 153       }
 154
 155       fprintf(stderr, "NIR (SSA form) for %s shader:\n",
 156               _mesa_shader_stage_to_string(stage));
 157       nir_print_shader(nir, stderr);
 158    }
 159
 160    nir_convert_from_ssa(nir, true);
 161    nir_validate_shader(nir);
 162
 163    /* This is the last pass we run before we start emitting stuff.  It
 164     * determines when we need to insert boolean resolves on Gen <= 5.  We
 165     * run it last because it stashes data in instr->pass_flags and we don't
 166     * want that to be squashed by other NIR passes.
 167     */
 168    if (brw->gen <= 5)
 169       brw_nir_analyze_boolean_resolves(nir);
 170
 171    nir_sweep(nir);
 172
 173    if (unlikely(debug_enabled)) {
 174       fprintf(stderr, "NIR (final form) for %s shader:\n",
 175               _mesa_shader_stage_to_string(stage));
 176       nir_print_shader(nir, stderr);
 177    }
 178
 179    return nir;
 180 }