/* * Copyright © 2019 Valve 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: * Rhys Perry (pendingchaos02@gmail.com) * */ #include #include "aco_ir.h" #include "aco_builder.h" #include namespace aco { struct phi_use { Block *block; unsigned phi_def; bool operator<(const phi_use& other) const { return std::make_tuple(block, phi_def) < std::make_tuple(other.block, other.phi_def); } }; struct ssa_state { std::map latest; std::map> phis; }; Operand get_ssa(Program *program, unsigned block_idx, ssa_state *state) { while (true) { auto pos = state->latest.find(block_idx); if (pos != state->latest.end()) return Operand({pos->second, s2}); Block& block = program->blocks[block_idx]; size_t pred = block.linear_preds.size(); if (pred == 0) { return Operand(s2); } else if (pred == 1) { block_idx = block.linear_preds[0]; continue; } else { unsigned res = program->allocateId(); state->latest[block_idx] = res; aco_ptr phi{create_instruction(aco_opcode::p_linear_phi, Format::PSEUDO, pred, 1)}; for (unsigned i = 0; i < pred; i++) { phi->operands[i] = get_ssa(program, block.linear_preds[i], state); if (phi->operands[i].isTemp()) { assert(i < 64); state->phis[phi->operands[i].tempId()][(phi_use){&block, res}] |= (uint64_t)1 << i; } } phi->definitions[0] = Definition(Temp{res, s2}); block.instructions.emplace(block.instructions.begin(), std::move(phi)); return Operand({res, s2}); } } } void update_phi(Program *program, ssa_state *state, Block *block, unsigned phi_def, uint64_t operand_mask) { for (auto& phi : block->instructions) { if (phi->opcode != aco_opcode::p_phi && phi->opcode != aco_opcode::p_linear_phi) break; if (phi->opcode != aco_opcode::p_linear_phi) continue; if (phi->definitions[0].tempId() != phi_def) continue; assert(ffsll(operand_mask) <= phi->operands.size()); uint64_t operands = operand_mask; while (operands) { unsigned operand = u_bit_scan64(&operands); Operand new_operand = get_ssa(program, block->linear_preds[operand], state); phi->operands[operand] = new_operand; if (!new_operand.isUndefined()) state->phis[new_operand.tempId()][(phi_use){block, phi_def}] |= (uint64_t)1 << operand; } return; } assert(false); } Temp write_ssa(Program *program, Block *block, ssa_state *state, unsigned previous) { unsigned id = program->allocateId(); state->latest[block->index] = id; /* update phis */ if (previous) { std::map phis; phis.swap(state->phis[previous]); for (auto& phi : phis) update_phi(program, state, phi.first.block, phi.first.phi_def, phi.second); } return {id, s2}; } void insert_before_logical_end(Block *block, aco_ptr instr) { auto IsLogicalEnd = [] (const aco_ptr& instr) -> bool { return instr->opcode == aco_opcode::p_logical_end; }; auto it = std::find_if(block->instructions.crbegin(), block->instructions.crend(), IsLogicalEnd); if (it == block->instructions.crend()) { assert(block->instructions.back()->format == Format::PSEUDO_BRANCH); block->instructions.insert(std::prev(block->instructions.end()), std::move(instr)); } else block->instructions.insert(std::prev(it.base()), std::move(instr)); } void lower_divergent_bool_phi(Program *program, Block *block, aco_ptr& phi) { Builder bld(program); ssa_state state; state.latest[block->index] = phi->definitions[0].tempId(); for (unsigned i = 0; i < phi->operands.size(); i++) { Block *pred = &program->blocks[block->logical_preds[i]]; if (phi->operands[i].isUndefined()) continue; assert(phi->operands[i].isTemp()); Temp phi_src = phi->operands[i].getTemp(); if (phi_src.regClass() == s1) { Temp new_phi_src = bld.tmp(s2); insert_before_logical_end(pred, bld.sop2(aco_opcode::s_cselect_b64, Definition(new_phi_src), Operand((uint32_t)-1), Operand(0u), bld.scc(phi_src)).get_ptr()); phi_src = new_phi_src; } assert(phi_src.regClass() == s2); Operand cur = get_ssa(program, pred->index, &state); Temp new_cur = write_ssa(program, pred, &state, cur.isTemp() ? cur.tempId() : 0); if (cur.isUndefined()) { insert_before_logical_end(pred, bld.sop1(aco_opcode::s_mov_b64, Definition(new_cur), phi_src).get_ptr()); } else { Temp tmp1 = bld.tmp(s2), tmp2 = bld.tmp(s2); insert_before_logical_end(pred, bld.sop2(aco_opcode::s_andn2_b64, Definition(tmp1), bld.def(s1, scc), cur, Operand(exec, s2)).get_ptr()); insert_before_logical_end(pred, bld.sop2(aco_opcode::s_and_b64, Definition(tmp2), bld.def(s1, scc), phi_src, Operand(exec, s2)).get_ptr()); insert_before_logical_end(pred, bld.sop2(aco_opcode::s_or_b64, Definition(new_cur), bld.def(s1, scc), tmp1, tmp2).get_ptr()); } } unsigned num_preds = block->linear_preds.size(); if (phi->operands.size() != num_preds) { Pseudo_instruction* new_phi{create_instruction(aco_opcode::p_linear_phi, Format::PSEUDO, num_preds, 1)}; new_phi->definitions[0] = phi->definitions[0]; phi.reset(new_phi); } else { phi->opcode = aco_opcode::p_linear_phi; } assert(phi->operands.size() == num_preds); for (unsigned i = 0; i < num_preds; i++) phi->operands[i] = get_ssa(program, block->linear_preds[i], &state); return; } void lower_linear_bool_phi(Program *program, Block *block, aco_ptr& phi) { Builder bld(program); for (unsigned i = 0; i < phi->operands.size(); i++) { if (!phi->operands[i].isTemp()) continue; Temp phi_src = phi->operands[i].getTemp(); if (phi_src.regClass() == s2) { Temp new_phi_src = bld.tmp(s1); insert_before_logical_end(&program->blocks[block->linear_preds[i]], bld.sopc(aco_opcode::s_cmp_lg_u64, bld.scc(Definition(new_phi_src)), Operand(0u), phi_src).get_ptr()); phi->operands[i].setTemp(new_phi_src); } } } void lower_bool_phis(Program* program) { for (Block& block : program->blocks) { for (aco_ptr& phi : block.instructions) { if (phi->opcode == aco_opcode::p_phi) { if (phi->definitions[0].regClass() == s2) lower_divergent_bool_phi(program, &block, phi); } else if (phi->opcode == aco_opcode::p_linear_phi) { /* if it's a valid non-boolean phi, this should be a no-op */ if (phi->definitions[0].regClass() == s1) lower_linear_bool_phi(program, &block, phi); } else { break; } } } } }