| /* |
| * 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. |
| * |
| * Authors: |
| * Connor Abbott (cwabbott0@gmail.com) |
| * |
| */ |
| |
| #include "nir.h" |
| #include <main/imports.h> |
| |
| /** |
| * SSA-based copy propagation |
| */ |
| |
| static bool is_move(nir_alu_instr *instr) |
| { |
| if (instr->op != nir_op_fmov && |
| instr->op != nir_op_imov) |
| return false; |
| |
| if (instr->dest.saturate) |
| return false; |
| |
| /* we handle modifiers in a separate pass */ |
| |
| if (instr->src[0].abs || instr->src[0].negate) |
| return false; |
| |
| if (!instr->src[0].src.is_ssa) |
| return false; |
| |
| return true; |
| |
| } |
| |
| static bool is_vec(nir_alu_instr *instr) |
| { |
| for (unsigned i = 0; i < nir_op_infos[instr->op].num_inputs; i++) { |
| if (!instr->src[i].src.is_ssa) |
| return false; |
| |
| /* we handle modifiers in a separate pass */ |
| if (instr->src[i].abs || instr->src[i].negate) |
| return false; |
| } |
| |
| return instr->op == nir_op_vec2 || |
| instr->op == nir_op_vec3 || |
| instr->op == nir_op_vec4; |
| } |
| |
| static bool |
| is_swizzleless_move(nir_alu_instr *instr) |
| { |
| if (is_move(instr)) { |
| for (unsigned i = 0; i < 4; i++) { |
| if (!((instr->dest.write_mask >> i) & 1)) |
| break; |
| if (instr->src[0].swizzle[i] != i) |
| return false; |
| } |
| return true; |
| } else if (is_vec(instr)) { |
| nir_ssa_def *def = NULL; |
| for (unsigned i = 0; i < nir_op_infos[instr->op].num_inputs; i++) { |
| if (instr->src[i].swizzle[0] != i) |
| return false; |
| |
| if (def == NULL) { |
| def = instr->src[i].src.ssa; |
| } else if (instr->src[i].src.ssa != def) { |
| return false; |
| } |
| } |
| return true; |
| } else { |
| return false; |
| } |
| } |
| |
| static bool |
| copy_prop_src(nir_src *src, nir_instr *parent_instr, nir_if *parent_if) |
| { |
| if (!src->is_ssa) { |
| if (src->reg.indirect) |
| return copy_prop_src(src, parent_instr, parent_if); |
| return false; |
| } |
| |
| nir_instr *src_instr = src->ssa->parent_instr; |
| if (src_instr->type != nir_instr_type_alu) |
| return false; |
| |
| nir_alu_instr *alu_instr = nir_instr_as_alu(src_instr); |
| if (!is_swizzleless_move(alu_instr)) |
| return false; |
| |
| /* Don't let copy propagation land us with a phi that has more |
| * components in its source than it has in its destination. That badly |
| * messes up out-of-ssa. |
| */ |
| if (parent_instr && parent_instr->type == nir_instr_type_phi) { |
| nir_phi_instr *phi = nir_instr_as_phi(parent_instr); |
| assert(phi->dest.is_ssa); |
| if (phi->dest.ssa.num_components != |
| alu_instr->src[0].src.ssa->num_components) |
| return false; |
| } |
| |
| if (parent_instr) { |
| nir_instr_rewrite_src(parent_instr, src, |
| nir_src_for_ssa(alu_instr->src[0].src.ssa)); |
| } else { |
| assert(src == &parent_if->condition); |
| nir_if_rewrite_condition(parent_if, |
| nir_src_for_ssa(alu_instr->src[0].src.ssa)); |
| } |
| |
| return true; |
| } |
| |
| static bool |
| copy_prop_alu_src(nir_alu_instr *parent_alu_instr, unsigned index) |
| { |
| nir_alu_src *src = &parent_alu_instr->src[index]; |
| if (!src->src.is_ssa) { |
| if (src->src.reg.indirect) |
| return copy_prop_src(src->src.reg.indirect, &parent_alu_instr->instr, |
| NULL); |
| return false; |
| } |
| |
| nir_instr *src_instr = src->src.ssa->parent_instr; |
| if (src_instr->type != nir_instr_type_alu) |
| return false; |
| |
| nir_alu_instr *alu_instr = nir_instr_as_alu(src_instr); |
| if (!is_move(alu_instr) && !is_vec(alu_instr)) |
| return false; |
| |
| nir_ssa_def *def; |
| unsigned new_swizzle[4] = {0, 0, 0, 0}; |
| |
| if (alu_instr->op == nir_op_fmov || |
| alu_instr->op == nir_op_imov) { |
| for (unsigned i = 0; i < 4; i++) |
| new_swizzle[i] = alu_instr->src[0].swizzle[src->swizzle[i]]; |
| def = alu_instr->src[0].src.ssa; |
| } else { |
| def = NULL; |
| |
| for (unsigned i = 0; i < 4; i++) { |
| if (!nir_alu_instr_channel_used(parent_alu_instr, index, i)) |
| continue; |
| |
| nir_ssa_def *new_def = alu_instr->src[src->swizzle[i]].src.ssa; |
| if (def == NULL) |
| def = new_def; |
| else { |
| if (def != new_def) |
| return false; |
| } |
| new_swizzle[i] = alu_instr->src[src->swizzle[i]].swizzle[0]; |
| } |
| } |
| |
| for (unsigned i = 0; i < 4; i++) |
| src->swizzle[i] = new_swizzle[i]; |
| |
| nir_instr_rewrite_src(&parent_alu_instr->instr, &src->src, |
| nir_src_for_ssa(def)); |
| |
| return true; |
| } |
| |
| typedef struct { |
| nir_instr *parent_instr; |
| bool progress; |
| } copy_prop_state; |
| |
| static bool |
| copy_prop_src_cb(nir_src *src, void *_state) |
| { |
| copy_prop_state *state = (copy_prop_state *) _state; |
| while (copy_prop_src(src, state->parent_instr, NULL)) |
| state->progress = true; |
| |
| return true; |
| } |
| |
| static bool |
| copy_prop_instr(nir_instr *instr) |
| { |
| if (instr->type == nir_instr_type_alu) { |
| nir_alu_instr *alu_instr = nir_instr_as_alu(instr); |
| bool progress = false; |
| |
| for (unsigned i = 0; i < nir_op_infos[alu_instr->op].num_inputs; i++) |
| while (copy_prop_alu_src(alu_instr, i)) |
| progress = true; |
| |
| if (!alu_instr->dest.dest.is_ssa && alu_instr->dest.dest.reg.indirect) |
| while (copy_prop_src(alu_instr->dest.dest.reg.indirect, instr, NULL)) |
| progress = true; |
| |
| return progress; |
| } |
| |
| copy_prop_state state; |
| state.parent_instr = instr; |
| state.progress = false; |
| nir_foreach_src(instr, copy_prop_src_cb, &state); |
| |
| return state.progress; |
| } |
| |
| static bool |
| copy_prop_if(nir_if *if_stmt) |
| { |
| return copy_prop_src(&if_stmt->condition, NULL, if_stmt); |
| } |
| |
| static bool |
| copy_prop_block(nir_block *block, void *_state) |
| { |
| bool *progress = (bool *) _state; |
| |
| nir_foreach_instr(block, instr) { |
| if (copy_prop_instr(instr)) |
| *progress = true; |
| } |
| |
| if (block->cf_node.node.next != NULL && /* check that we aren't the end node */ |
| !nir_cf_node_is_last(&block->cf_node) && |
| nir_cf_node_next(&block->cf_node)->type == nir_cf_node_if) { |
| nir_if *if_stmt = nir_cf_node_as_if(nir_cf_node_next(&block->cf_node)); |
| if (copy_prop_if(if_stmt)) |
| *progress = true; |
| } |
| |
| return true; |
| } |
| |
| static bool |
| nir_copy_prop_impl(nir_function_impl *impl) |
| { |
| bool progress = false; |
| |
| nir_foreach_block(impl, copy_prop_block, &progress); |
| |
| if (progress) { |
| nir_metadata_preserve(impl, nir_metadata_block_index | |
| nir_metadata_dominance); |
| } |
| |
| return progress; |
| } |
| |
| bool |
| nir_copy_prop(nir_shader *shader) |
| { |
| bool progress = false; |
| |
| nir_foreach_function(shader, function) { |
| if (function->impl && nir_copy_prop_impl(function->impl)) |
| progress = true; |
| } |
| |
| return progress; |
| } |