| /* |
| * Copyright 2018-2019 Collabora Ltd. |
| * |
| * 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 |
| * on the rights to use, copy, modify, merge, publish, distribute, sub |
| * license, 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 NON-INFRINGEMENT. IN NO EVENT SHALL |
| * THE AUTHOR(S) AND/OR THEIR SUPPLIERS 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_builder.h" |
| |
| static void |
| lower_pos_write(nir_builder *b, struct nir_instr *instr) |
| { |
| if (instr->type != nir_instr_type_intrinsic) |
| return; |
| |
| nir_intrinsic_instr *intr = nir_instr_as_intrinsic(instr); |
| if (intr->intrinsic != nir_intrinsic_store_deref) |
| return; |
| |
| nir_variable *var = nir_intrinsic_get_var(intr, 0); |
| if (var->data.mode != nir_var_shader_out || |
| var->data.location != VARYING_SLOT_POS) |
| return; |
| |
| b->cursor = nir_before_instr(&intr->instr); |
| |
| nir_ssa_def *pos = nir_ssa_for_src(b, intr->src[1], 4); |
| nir_ssa_def *def = nir_vec4(b, |
| nir_channel(b, pos, 0), |
| nir_channel(b, pos, 1), |
| nir_fmul_imm(b, |
| nir_fadd(b, |
| nir_channel(b, pos, 2), |
| nir_channel(b, pos, 3)), |
| 0.5), |
| nir_channel(b, pos, 3)); |
| nir_instr_rewrite_src(&intr->instr, intr->src + 1, nir_src_for_ssa(def)); |
| } |
| |
| void |
| nir_lower_clip_halfz(nir_shader *shader) |
| { |
| if (shader->info.stage != MESA_SHADER_VERTEX && |
| shader->info.stage != MESA_SHADER_GEOMETRY && |
| shader->info.stage != MESA_SHADER_TESS_EVAL) |
| return; |
| |
| nir_foreach_function(function, shader) { |
| if (function->impl) { |
| nir_builder b; |
| nir_builder_init(&b, function->impl); |
| |
| nir_foreach_block(block, function->impl) { |
| nir_foreach_instr_safe(instr, block) { |
| lower_pos_write(&b, instr); |
| } |
| } |
| |
| nir_metadata_preserve(function->impl, nir_metadata_block_index | |
| nir_metadata_dominance); |
| } |
| } |
| } |