/* * 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) 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); } } }