| /* |
| * Copyright © 2019 Google, Inc. |
| * |
| * 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 "ir3_nir.h" |
| #include "compiler/nir/nir_builder.h" |
| |
| /** |
| * This pass lowers load_barycentric_at_sample to load_sample_pos_from_id |
| * plus load_barycentric_at_offset. |
| * |
| * It also lowers load_sample_pos to load_sample_pos_from_id, mostly because |
| * that needs to happen at the same early stage (before wpos_ytransform) |
| */ |
| |
| static nir_ssa_def * |
| load_sample_pos(nir_builder *b, nir_ssa_def *samp_id) |
| { |
| nir_intrinsic_instr *load_sp = |
| nir_intrinsic_instr_create(b->shader, |
| nir_intrinsic_load_sample_pos_from_id); |
| load_sp->num_components = 2; |
| load_sp->src[0] = nir_src_for_ssa(samp_id); |
| nir_ssa_dest_init(&load_sp->instr, &load_sp->dest, 2, 32, NULL); |
| nir_builder_instr_insert(b, &load_sp->instr); |
| |
| return &load_sp->dest.ssa; |
| } |
| |
| static nir_ssa_def * |
| lower_load_barycentric_at_sample(nir_builder *b, nir_intrinsic_instr *intr) |
| { |
| nir_ssa_def *pos = load_sample_pos(b, intr->src[0].ssa); |
| |
| nir_intrinsic_instr *load_bary_at_offset = |
| nir_intrinsic_instr_create(b->shader, |
| nir_intrinsic_load_barycentric_at_offset); |
| load_bary_at_offset->num_components = 2; |
| load_bary_at_offset->src[0] = nir_src_for_ssa(pos); |
| nir_ssa_dest_init(&load_bary_at_offset->instr, |
| &load_bary_at_offset->dest, 2, 32, NULL); |
| nir_builder_instr_insert(b, &load_bary_at_offset->instr); |
| |
| return &load_bary_at_offset->dest.ssa; |
| } |
| |
| static nir_ssa_def * |
| lower_load_sample_pos(nir_builder *b, nir_intrinsic_instr *intr) |
| { |
| nir_ssa_def *pos = load_sample_pos(b, nir_load_sample_id(b)); |
| |
| /* Note that gl_SamplePosition is offset by +vec2(0.5, 0.5) vs the |
| * offset passed to interpolateAtOffset(). See |
| * dEQP-GLES31.functional.shaders.multisample_interpolation.interpolate_at_offset.at_sample_position.default_framebuffer |
| * for example. |
| */ |
| nir_ssa_def *half = nir_imm_float(b, 0.5); |
| return nir_fadd(b, pos, nir_vec2(b, half, half)); |
| } |
| |
| static nir_ssa_def * |
| ir3_nir_lower_load_barycentric_at_sample_instr(nir_builder *b, |
| nir_instr *instr, void *data) |
| { |
| nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr); |
| |
| if (intr->intrinsic == nir_intrinsic_load_sample_pos) |
| return lower_load_sample_pos(b, intr); |
| else |
| return lower_load_barycentric_at_sample(b, intr); |
| } |
| |
| static bool |
| ir3_nir_lower_load_barycentric_at_sample_filter(const nir_instr *instr, |
| const void *data) |
| { |
| if (instr->type != nir_instr_type_intrinsic) |
| return false; |
| nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr); |
| return (intr->intrinsic == nir_intrinsic_load_barycentric_at_sample || |
| intr->intrinsic == nir_intrinsic_load_sample_pos); |
| } |
| |
| bool |
| ir3_nir_lower_load_barycentric_at_sample(nir_shader *shader) |
| { |
| debug_assert(shader->info.stage == MESA_SHADER_FRAGMENT); |
| |
| return nir_shader_lower_instructions(shader, |
| ir3_nir_lower_load_barycentric_at_sample_filter, |
| ir3_nir_lower_load_barycentric_at_sample_instr, |
| NULL); |
| } |