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 static bool
  61 count_nir_instrs_in_block(nir_block *block, void *state)
  62 {
  63    int *count = (int *) state;
  64    nir_foreach_instr(block, instr) {
  65       *count = *count + 1;
  66    }
  67    return true;
  68 }
  69
  70 static int
  71 count_nir_instrs(nir_shader *nir)
  72 {
  73    int count = 0;
  74    nir_foreach_overload(nir, overload) {
  75       if (!overload->impl)
  76          continue;
  77       nir_foreach_block(overload->impl, count_nir_instrs_in_block, &count);
  78    }
  79    return count;
  80 }
  81
  82 nir_shader *
  83 brw_create_nir(struct brw_context *brw,
  84                const struct gl_shader_program *shader_prog,
  85                const struct gl_program *prog,
  86                gl_shader_stage stage)
  87 {
  88    struct gl_context *ctx = &brw->ctx;
  89    const nir_shader_compiler_options *options =
  90       ctx->Const.ShaderCompilerOptions[stage].NirOptions;
  91    struct gl_shader *shader = shader_prog ? shader_prog->_LinkedShaders[stage] : NULL;
  92    bool debug_enabled = INTEL_DEBUG & intel_debug_flag_for_shader_stage(stage);
  93    nir_shader *nir;
  94
  95    /* First, lower the GLSL IR or Mesa IR to NIR */
  96    if (shader_prog) {
  97       nir = glsl_to_nir(shader, options);
  98    } else {
  99       nir = prog_to_nir(prog, options);
 100       nir_convert_to_ssa(nir); /* turn registers into SSA */
 101    }
 102    nir_validate_shader(nir);
 103
 104    nir_lower_global_vars_to_local(nir);
 105    nir_validate_shader(nir);
 106
 107    nir_lower_tex_projector(nir);
 108    nir_validate_shader(nir);
 109
 110    nir_normalize_cubemap_coords(nir);
 111    nir_validate_shader(nir);
 112
 113    nir_split_var_copies(nir);
 114    nir_validate_shader(nir);
 115
 116    nir_optimize(nir);
 117
 118    /* Lower a bunch of stuff */
 119    nir_lower_var_copies(nir);
 120    nir_validate_shader(nir);
 121
 122    /* Get rid of split copies */
 123    nir_optimize(nir);
 124
 125    if (shader_prog) {
 126       nir_assign_var_locations_scalar_direct_first(nir, &nir->uniforms,
 127                                                    &nir->num_direct_uniforms,
 128                                                    &nir->num_uniforms);
 129    } else {
 130       /* ARB programs generally create a giant array of "uniform" data, and allow
 131        * indirect addressing without any boundaries.  In the absence of bounds
 132        * analysis, it's all or nothing.  num_direct_uniforms is only useful when
 133        * we have some direct and some indirect access; it doesn't matter here.
 134        */
 135       nir->num_direct_uniforms = 0;
 136    }
 137    nir_assign_var_locations_scalar(&nir->inputs, &nir->num_inputs);
 138    nir_assign_var_locations_scalar(&nir->outputs, &nir->num_outputs);
 139
 140    nir_lower_io(nir);
 141    nir_validate_shader(nir);
 142
 143    nir_remove_dead_variables(nir);
 144    nir_validate_shader(nir);
 145
 146    if (shader_prog) {
 147       nir_lower_samplers_for_vk(nir);
 148       nir_validate_shader(nir);
 149    }
 150
 151    nir_lower_system_values(nir);
 152    nir_validate_shader(nir);
 153
 154    nir_lower_atomics(nir);
 155    nir_validate_shader(nir);
 156
 157    nir_optimize(nir);
 158
 159    if (brw->gen >= 6) {
 160       /* Try and fuse multiply-adds */
 161       nir_opt_peephole_ffma(nir);
 162       nir_validate_shader(nir);
 163    }
 164
 165    nir_opt_algebraic_late(nir);
 166    nir_validate_shader(nir);
 167
 168    nir_lower_locals_to_regs(nir);
 169    nir_validate_shader(nir);
 170
 171    nir_lower_to_source_mods(nir);
 172    nir_validate_shader(nir);
 173    nir_copy_prop(nir);
 174    nir_validate_shader(nir);
 175    nir_opt_dce(nir);
 176    nir_validate_shader(nir);
 177
 178    if (unlikely(debug_enabled)) {
 179       fprintf(stderr, "NIR (SSA form) for %s shader:\n",
 180               _mesa_shader_stage_to_string(stage));
 181       nir_print_shader(nir, stderr);
 182    }
 183
 184    static GLuint msg_id = 0;
 185    _mesa_gl_debug(&brw->ctx, &msg_id,
 186                   MESA_DEBUG_SOURCE_SHADER_COMPILER,
 187                   MESA_DEBUG_TYPE_OTHER,
 188                   MESA_DEBUG_SEVERITY_NOTIFICATION,
 189                   "%s NIR shader: %d inst\n",
 190                   _mesa_shader_stage_to_abbrev(stage),
 191                   count_nir_instrs(nir));
 192
 193    nir_convert_from_ssa(nir);
 194    nir_validate_shader(nir);
 195
 196    /* This is the last pass we run before we start emitting stuff.  It
 197     * determines when we need to insert boolean resolves on Gen <= 5.  We
 198     * run it last because it stashes data in instr->pass_flags and we don't
 199     * want that to be squashed by other NIR passes.
 200     */
 201    if (brw->gen <= 5)
 202       brw_nir_analyze_boolean_resolves(nir);
 203
 204    nir_sweep(nir);
 205
 206    if (unlikely(debug_enabled)) {
 207       fprintf(stderr, "NIR (final form) for %s shader:\n",
 208               _mesa_shader_stage_to_string(stage));
 209       nir_print_shader(nir, stderr);
 210    }
 211
 212    return nir;
 213 }