diff --git a/src/compiler/Makefile.sources b/src/compiler/Makefile.sources index 66777c7213e..a3a04f88c23 100644 --- a/src/compiler/Makefile.sources +++ b/src/compiler/Makefile.sources @@ -278,6 +278,7 @@ NIR_FILES = \ nir/nir_lower_io_to_temporaries.c \ nir/nir_lower_io_to_scalar.c \ nir/nir_lower_io_to_vector.c \ + nir/nir_lower_is_helper_invocation.c \ nir/nir_lower_multiview.c \ nir/nir_lower_mediump.c \ nir/nir_lower_memcpy.c \ diff --git a/src/compiler/nir/meson.build b/src/compiler/nir/meson.build index d17bbe504a5..1fcd4fc6a22 100644 --- a/src/compiler/nir/meson.build +++ b/src/compiler/nir/meson.build @@ -167,6 +167,7 @@ files_libnir = files( 'nir_lower_io_to_temporaries.c', 'nir_lower_io_to_scalar.c', 'nir_lower_io_to_vector.c', + 'nir_lower_is_helper_invocation.c', 'nir_lower_multiview.c', 'nir_lower_mediump.c', 'nir_lower_memcpy.c', diff --git a/src/compiler/nir/nir.h b/src/compiler/nir/nir.h index a0a646610db..cbe5ab94f3b 100644 --- a/src/compiler/nir/nir.h +++ b/src/compiler/nir/nir.h @@ -4633,6 +4633,8 @@ bool nir_lower_fragcoord_wtrans(nir_shader *shader); void nir_lower_viewport_transform(nir_shader *shader); bool nir_lower_uniforms_to_ubo(nir_shader *shader, bool dword_packed, bool load_vec4); +bool nir_lower_is_helper_invocation(nir_shader *shader); + typedef struct nir_lower_subgroups_options { uint8_t subgroup_size; uint8_t ballot_bit_size; diff --git a/src/compiler/nir/nir_lower_is_helper_invocation.c b/src/compiler/nir/nir_lower_is_helper_invocation.c new file mode 100644 index 00000000000..38263d5c2ec --- /dev/null +++ b/src/compiler/nir/nir_lower_is_helper_invocation.c @@ -0,0 +1,126 @@ +/* + * Copyright © 2021 Igalia S.L. + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include "nir.h" +#include "nir_builder.h" + +/* Some hardware doesn't have a way to check if invocation was demoted, + * in such case we have to track it ourselves. + * OpIsHelperInvocationEXT is specified as: + * + * "An invocation is currently a helper invocation if it was originally + * invoked as a helper invocation or if it has been demoted to a helper + * invocation by OpDemoteToHelperInvocationEXT." + * + * Therefore we: + * - Set gl_IsHelperInvocationEXT = gl_HelperInvocation + * - Add "gl_IsHelperInvocationEXT = true" right before each demote + * - Add "gl_IsHelperInvocationEXT = gl_IsHelperInvocationEXT || condition" + * right before each demote_if + */ + +static bool +nir_lower_load_and_store_is_helper(nir_builder *b, nir_instr *instr, void *data) +{ + if (instr->type != nir_instr_type_intrinsic) + return false; + + nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr); + nir_deref_instr *is_helper_deref = (nir_deref_instr*) data; + + switch (intrin->intrinsic) { + case nir_intrinsic_demote: { + b->cursor = nir_before_instr(instr); + nir_store_deref(b, is_helper_deref, nir_imm_bool(b, true), 1); + return true; + } + case nir_intrinsic_demote_if: { + b->cursor = nir_before_instr(instr); + nir_ssa_def *current_is_helper = nir_load_deref(b, is_helper_deref); + nir_ssa_def *updated_is_helper = nir_ior(b, current_is_helper, intrin->src[0].ssa); + nir_store_deref(b, is_helper_deref, updated_is_helper, 1); + return true; + } + case nir_intrinsic_is_helper_invocation: { + b->cursor = nir_before_instr(instr); + nir_ssa_def *is_helper = nir_load_deref(b, is_helper_deref); + nir_ssa_def_rewrite_uses(&intrin->dest.ssa, is_helper); + nir_instr_remove_v(instr); + return true; + } + default: + return false; + } +} + +static bool +has_is_helper_invocation(nir_shader *shader) +{ + nir_foreach_function(function, shader) { + if (!function->impl) + continue; + + nir_foreach_block_safe(block, function->impl) { + nir_foreach_instr_safe(instr, block) { + if (instr->type != nir_instr_type_intrinsic) + continue; + + nir_intrinsic_instr *intrin = nir_instr_as_intrinsic(instr); + if (intrin->intrinsic == nir_intrinsic_is_helper_invocation) + return true; + } + } + } + + return false; +} + +bool +nir_lower_is_helper_invocation(nir_shader *shader) +{ + if (shader->info.stage != MESA_SHADER_FRAGMENT) + return false; + + if (!has_is_helper_invocation(shader)) + return false; + + nir_function_impl *entrypoint = nir_shader_get_entrypoint(shader); + + nir_builder b; + nir_builder_init(&b, entrypoint); + b.cursor = nir_before_cf_list(&entrypoint->body); + + nir_variable *is_helper = nir_local_variable_create(entrypoint, + glsl_bool_type(), + "gl_IsHelperInvocationEXT"); + + nir_ssa_def *started_as_helper = nir_load_helper_invocation(&b, 32); + + nir_deref_instr *is_helper_deref = nir_build_deref_var(&b, is_helper); + nir_store_deref(&b, is_helper_deref, started_as_helper, 1); + + return nir_shader_instructions_pass(shader, + nir_lower_load_and_store_is_helper, + nir_metadata_all, + is_helper_deref); +}