--- /dev/null
+/*
+ * 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 <map>
+
+#include "aco_ir.h"
+#include "aco_builder.h"
+#include <algorithm>
+
+
+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<unsigned, unsigned> latest;
+ std::map<unsigned, std::map<phi_use, uint64_t>> 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(Temp(pos->second, program->lane_mask));
+
+ Block& block = program->blocks[block_idx];
+ size_t pred = block.linear_preds.size();
+ if (pred == 0) {
+ return Operand(program->lane_mask);
+ } else if (pred == 1) {
+ block_idx = block.linear_preds[0];
+ continue;
+ } else {
+ unsigned res = program->allocateId();
+ state->latest[block_idx] = res;
+
+ aco_ptr<Pseudo_instruction> phi{create_instruction<Pseudo_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, program->lane_mask});
+ block.instructions.emplace(block.instructions.begin(), std::move(phi));
+
+ return Operand(Temp(res, program->lane_mask));
+ }
+ }
+}
+
+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<phi_use, uint64_t> 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, program->lane_mask};
+}
+
+void insert_before_logical_end(Block *block, aco_ptr<Instruction> instr)
+{
+ auto IsLogicalEnd = [] (const aco_ptr<Instruction>& 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<Instruction>& 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();
+ assert(phi_src.regClass() == bld.lm);
+
+ Operand cur = get_ssa(program, pred->index, &state);
+ assert(cur.regClass() == bld.lm);
+ Temp new_cur = write_ssa(program, pred, &state, cur.isTemp() ? cur.tempId() : 0);
+ assert(new_cur.regClass() == bld.lm);
+
+ 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(bld.lm), tmp2 = bld.tmp(bld.lm);
+ insert_before_logical_end(pred,
+ bld.sop2(Builder::s_andn2, Definition(tmp1), bld.def(s1, scc),
+ cur, Operand(exec, bld.lm)).get_ptr());
+ insert_before_logical_end(pred,
+ bld.sop2(Builder::s_and, Definition(tmp2), bld.def(s1, scc),
+ phi_src, Operand(exec, bld.lm)).get_ptr());
+ insert_before_logical_end(pred,
+ bld.sop2(Builder::s_or, 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<Pseudo_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_subdword_phis(Program *program, Block *block, aco_ptr<Instruction>& phi)
+{
+ Builder bld(program);
+ for (unsigned i = 0; i < phi->operands.size(); i++) {
+ if (phi->operands[i].isUndefined())
+ continue;
+ if (phi->operands[i].regClass() == phi->definitions[0].regClass())
+ continue;
+
+ assert(phi->operands[i].isTemp());
+ Block *pred = &program->blocks[block->logical_preds[i]];
+ Temp phi_src = phi->operands[i].getTemp();
+
+ assert(phi_src.regClass().type() == RegType::sgpr);
+ Temp tmp = bld.tmp(RegClass(RegType::vgpr, phi_src.size()));
+ insert_before_logical_end(pred, bld.pseudo(aco_opcode::p_create_vector, Definition(tmp), phi_src).get_ptr());
+ Temp new_phi_src = bld.tmp(phi->definitions[0].regClass());
+ insert_before_logical_end(pred, bld.pseudo(aco_opcode::p_extract_vector, Definition(new_phi_src), tmp, Operand(0u)).get_ptr());
+
+ phi->operands[i].setTemp(new_phi_src);
+ }
+ return;
+}
+
+void lower_phis(Program* program)
+{
+ for (Block& block : program->blocks) {
+ for (aco_ptr<Instruction>& phi : block.instructions) {
+ if (phi->opcode == aco_opcode::p_phi) {
+ assert(program->wave_size == 64 ? phi->definitions[0].regClass() != s1 : phi->definitions[0].regClass() != s2);
+ if (phi->definitions[0].regClass() == program->lane_mask)
+ lower_divergent_bool_phi(program, &block, phi);
+ else if (phi->definitions[0].regClass().is_subdword())
+ lower_subdword_phis(program, &block, phi);
+ } else if (!is_phi(phi)) {
+ break;
+ }
+ }
+ }
+}
+
+}
projects / mesa.git / blobdiff