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 {
  66    struct gl_context *ctx = &brw->ctx;
  67    const nir_shader_compiler_options *options =
  68       ctx->Const.ShaderCompilerOptions[stage].NirOptions;
  69    struct gl_shader *shader = shader_prog ? shader_prog->_LinkedShaders[stage] : NULL;
  70    bool debug_enabled = INTEL_DEBUG & intel_debug_flag_for_shader_stage(stage);
  71    nir_shader *nir;
  72
  73    /* First, lower the GLSL IR or Mesa IR to NIR */
  74    if (shader_prog) {
  75       nir = glsl_to_nir(shader, options);
  76    } else {
  77       nir = prog_to_nir(prog, options);
  78       nir_convert_to_ssa(nir); /* turn registers into SSA */
  79    }
  80    nir_validate_shader(nir);
  81
  82    nir_lower_global_vars_to_local(nir);
  83    nir_validate_shader(nir);
  84
  85    nir_lower_tex_projector(nir);
  86    nir_validate_shader(nir);
  87
  88    nir_normalize_cubemap_coords(nir);
  89    nir_validate_shader(nir);
  90
  91    nir_split_var_copies(nir);
  92    nir_validate_shader(nir);
  93
  94    nir_optimize(nir);
  95
  96    /* Lower a bunch of stuff */
  97    nir_lower_var_copies(nir);
  98    nir_validate_shader(nir);
  99
 100    /* Get rid of split copies */
 101    nir_optimize(nir);
 102
 103    nir_assign_var_locations_scalar_direct_first(nir, &nir->uniforms,
 104                                                 &nir->num_direct_uniforms,
 105                                                 &nir->num_uniforms);
 106    nir_assign_var_locations_scalar(&nir->inputs, &nir->num_inputs);
 107    nir_assign_var_locations_scalar(&nir->outputs, &nir->num_outputs);
 108
 109    nir_lower_io(nir);
 110    nir_validate_shader(nir);
 111
 112    nir_remove_dead_variables(nir);
 113    nir_validate_shader(nir);
 114
 115    if (shader_prog) {
 116       nir_lower_samplers(nir, shader_prog, stage);
 117       nir_validate_shader(nir);
 118    }
 119
 120    nir_lower_system_values(nir);
 121    nir_validate_shader(nir);
 122
 123    nir_lower_atomics(nir);
 124    nir_validate_shader(nir);
 125
 126    nir_optimize(nir);
 127
 128    if (brw->gen >= 6) {
 129       /* Try and fuse multiply-adds */
 130       nir_opt_peephole_ffma(nir);
 131       nir_validate_shader(nir);
 132    }
 133
 134    nir_opt_algebraic_late(nir);
 135    nir_validate_shader(nir);
 136
 137    nir_lower_locals_to_regs(nir);
 138    nir_validate_shader(nir);
 139
 140    nir_lower_to_source_mods(nir);
 141    nir_validate_shader(nir);
 142    nir_copy_prop(nir);
 143    nir_validate_shader(nir);
 144    nir_opt_dce(nir);
 145    nir_validate_shader(nir);
 146
 147    if (unlikely(debug_enabled)) {
 148       /* Re-index SSA defs so we print more sensible numbers. */
 149       nir_foreach_overload(nir, overload) {
 150          if (overload->impl)
 151             nir_index_ssa_defs(overload->impl);
 152       }
 153
 154       fprintf(stderr, "NIR (SSA form) for %s shader:\n",
 155               _mesa_shader_stage_to_string(stage));
 156       nir_print_shader(nir, stderr);
 157    }
 158
 159    nir_convert_from_ssa(nir, false);
 160    nir_validate_shader(nir);
 161
 162    /* This is the last pass we run before we start emitting stuff.  It
 163     * determines when we need to insert boolean resolves on Gen <= 5.  We
 164     * run it last because it stashes data in instr->pass_flags and we don't
 165     * want that to be squashed by other NIR passes.
 166     */
 167    if (brw->gen <= 5)
 168       brw_nir_analyze_boolean_resolves(nir);
 169
 170    nir_sweep(nir);
 171
 172    if (unlikely(debug_enabled)) {
 173       fprintf(stderr, "NIR (final form) for %s shader:\n",
 174               _mesa_shader_stage_to_string(stage));
 175       nir_print_shader(nir, stderr);
 176    }
 177
 178    return nir;
 179 }