1 /* 2 * Copyright (c) 2016 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 "compiler/nir/nir_builder.h" 26 27 struct lower_intrinsics_state { 28 nir_shader *nir; 29 union { 30 struct brw_stage_prog_data *prog_data; 31 struct brw_cs_prog_data *cs_prog_data; 32 }; 33 nir_function_impl *impl; 34 bool progress; 35 nir_builder builder; 36 bool cs_thread_id_used; 37 }; 38 39 static nir_ssa_def * 40 read_thread_local_id(struct lower_intrinsics_state *state) 41 { 42 nir_builder *b = &state->builder; 43 nir_shader *nir = state->nir; 44 const unsigned *sizes = nir->info->cs.local_size; 45 const unsigned group_size = sizes[0] * sizes[1] * sizes[2]; 46 47 /* Some programs have local_size dimensions so small that the thread local 48 * ID will always be 0. 49 */ 50 if (group_size <= 8) 51 return nir_imm_int(b, 0); 52 53 assert(state->cs_prog_data->thread_local_id_index >= 0); 54 state->cs_thread_id_used = true; 55 const int id_index = state->cs_prog_data->thread_local_id_index; 56 57 nir_intrinsic_instr *load = 58 nir_intrinsic_instr_create(nir, nir_intrinsic_load_uniform); 59 load->num_components = 1; 60 load->src[0] = nir_src_for_ssa(nir_imm_int(b, 0)); 61 nir_ssa_dest_init(&load->instr, &load->dest, 1, 32, NULL); 62 nir_intrinsic_set_base(load, id_index * sizeof(uint32_t)); 63 nir_intrinsic_set_range(load, sizeof(uint32_t)); 64 nir_builder_instr_insert(b, &load->instr); 65 return &load->dest.ssa; 66 } 67 68 static bool 69 lower_cs_intrinsics_convert_block(struct lower_intrinsics_state *state, 70 nir_block *block) 71 { 72 bool progress = false; 73 nir_builder *b = &state->builder; 74 nir_shader *nir = state->nir; 75 76 nir_foreach_instr_safe(instr, block) { 77 if (instr->type != nir_instr_type_intrinsic) 78 continue; 79 80 nir_intrinsic_instr *intrinsic = nir_instr_as_intrinsic(instr); 81 82 b->cursor = nir_after_instr(&intrinsic->instr); 83 84 nir_ssa_def *sysval; 85 switch (intrinsic->intrinsic) { 86 case nir_intrinsic_load_local_invocation_index: { 87 assert(nir->stage == MESA_SHADER_COMPUTE); 88 /* We construct the local invocation index from: 89 * 90 * gl_LocalInvocationIndex = 91 * cs_thread_local_id + channel_num; 92 */ 93 nir_ssa_def *thread_local_id = read_thread_local_id(state); 94 nir_ssa_def *channel = nir_load_channel_num(b); 95 sysval = nir_iadd(b, channel, thread_local_id); 96 break; 97 } 98 99 case nir_intrinsic_load_local_invocation_id: { 100 assert(nir->stage == MESA_SHADER_COMPUTE); 101 /* We lower gl_LocalInvocationID from gl_LocalInvocationIndex based 102 * on this formula: 103 * 104 * gl_LocalInvocationID.x = 105 * gl_LocalInvocationIndex % gl_WorkGroupSize.x; 106 * gl_LocalInvocationID.y = 107 * (gl_LocalInvocationIndex / gl_WorkGroupSize.x) % 108 * gl_WorkGroupSize.y; 109 * gl_LocalInvocationID.z = 110 * (gl_LocalInvocationIndex / 111 * (gl_WorkGroupSize.x * gl_WorkGroupSize.y)) % 112 * gl_WorkGroupSize.z; 113 */ 114 unsigned *size = nir->info->cs.local_size; 115 116 nir_ssa_def *local_index = nir_load_local_invocation_index(b); 117 118 nir_const_value uvec3; 119 uvec3.u32[0] = 1; 120 uvec3.u32[1] = size[0]; 121 uvec3.u32[2] = size[0] * size[1]; 122 nir_ssa_def *div_val = nir_build_imm(b, 3, 32, uvec3); 123 uvec3.u32[0] = size[0]; 124 uvec3.u32[1] = size[1]; 125 uvec3.u32[2] = size[2]; 126 nir_ssa_def *mod_val = nir_build_imm(b, 3, 32, uvec3); 127 128 sysval = nir_umod(b, nir_udiv(b, local_index, div_val), mod_val); 129 break; 130 } 131 132 default: 133 continue; 134 } 135 136 nir_ssa_def_rewrite_uses(&intrinsic->dest.ssa, nir_src_for_ssa(sysval)); 137 nir_instr_remove(&intrinsic->instr); 138 139 state->progress = true; 140 } 141 142 return progress; 143 } 144 145 static void 146 lower_cs_intrinsics_convert_impl(struct lower_intrinsics_state *state) 147 { 148 nir_builder_init(&state->builder, state->impl); 149 150 nir_foreach_block(block, state->impl) { 151 lower_cs_intrinsics_convert_block(state, block); 152 } 153 154 nir_metadata_preserve(state->impl, 155 nir_metadata_block_index | nir_metadata_dominance); 156 } 157 158 bool 159 brw_nir_lower_intrinsics(nir_shader *nir, struct brw_stage_prog_data *prog_data) 160 { 161 /* Currently we only lower intrinsics for compute shaders */ 162 if (nir->stage != MESA_SHADER_COMPUTE) 163 return false; 164 165 bool progress = false; 166 struct lower_intrinsics_state state; 167 memset(&state, 0, sizeof(state)); 168 state.nir = nir; 169 state.prog_data = prog_data; 170 171 do { 172 state.progress = false; 173 nir_foreach_function(function, nir) { 174 if (function->impl) { 175 state.impl = function->impl; 176 lower_cs_intrinsics_convert_impl(&state); 177 } 178 } 179 progress |= state.progress; 180 } while (state.progress); 181 182 if (nir->stage == MESA_SHADER_COMPUTE && !state.cs_thread_id_used) 183 state.cs_prog_data->thread_local_id_index = -1; 184 185 return progress; 186 } 187
