/* * Copyright (C) 2005-2007 Brian Paul All Rights Reserved. * Copyright (C) 2008 VMware, Inc. All Rights Reserved. * Copyright © 2014 Intel Corporation * * 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/nir.h" #include "nir_builder.h" static void lower_tex_src_to_offset(nir_builder *b, nir_tex_instr *instr, unsigned src_idx) { nir_ssa_def *index = NULL; unsigned base_index = 0; unsigned array_elements = 1; nir_tex_src *src = &instr->src[src_idx]; bool is_sampler = src->src_type == nir_tex_src_sampler_deref; /* We compute first the offsets */ nir_deref_instr *deref = nir_instr_as_deref(src->src.ssa->parent_instr); while (deref->deref_type != nir_deref_type_var) { assert(deref->parent.is_ssa); nir_deref_instr *parent = nir_instr_as_deref(deref->parent.ssa->parent_instr); assert(deref->deref_type == nir_deref_type_array); if (nir_src_is_const(deref->arr.index) && index == NULL) { /* We're still building a direct index */ base_index += nir_src_as_uint(deref->arr.index) * array_elements; } else { if (index == NULL) { /* We used to be direct but not anymore */ index = nir_imm_int(b, base_index); base_index = 0; } index = nir_iadd(b, index, nir_imul(b, nir_imm_int(b, array_elements), nir_ssa_for_src(b, deref->arr.index, 1))); } array_elements *= glsl_get_length(parent->type); deref = parent; } if (index) index = nir_umin(b, index, nir_imm_int(b, array_elements - 1)); /* We hit the deref_var. This is the end of the line */ assert(deref->deref_type == nir_deref_type_var); base_index += deref->var->data.binding; /* We have the offsets, we apply them, rewriting the source or removing * instr if needed */ if (index) { nir_instr_rewrite_src(&instr->instr, &src->src, nir_src_for_ssa(index)); src->src_type = is_sampler ? nir_tex_src_sampler_offset : nir_tex_src_texture_offset; } else { nir_tex_instr_remove_src(instr, src_idx); } if (is_sampler) { instr->sampler_index = base_index; } else { instr->texture_index = base_index; } } static bool lower_sampler(nir_builder *b, nir_tex_instr *instr) { int texture_idx = nir_tex_instr_src_index(instr, nir_tex_src_texture_deref); if (texture_idx >= 0) { b->cursor = nir_before_instr(&instr->instr); lower_tex_src_to_offset(b, instr, texture_idx); } int sampler_idx = nir_tex_instr_src_index(instr, nir_tex_src_sampler_deref); if (sampler_idx >= 0) { lower_tex_src_to_offset(b, instr, sampler_idx); } if (texture_idx < 0 && sampler_idx < 0) return false; return true; } static bool lower_impl(nir_function_impl *impl) { nir_builder b; nir_builder_init(&b, impl); bool progress = false; nir_foreach_block(block, impl) { nir_foreach_instr(instr, block) { if (instr->type == nir_instr_type_tex) progress |= lower_sampler(&b, nir_instr_as_tex(instr)); } } return progress; } bool nir_lower_samplers(nir_shader *shader) { bool progress = false; /* Next, lower derefs to offsets. */ nir_foreach_function(function, shader) { if (function->impl) progress |= lower_impl(function->impl); } return progress; }