| // Copyright (c) 2020 Google LLC |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include "source/fuzz/transformation_replace_opphi_id_from_dead_predecessor.h" |
| |
| #include "source/fuzz/fuzzer_util.h" |
| |
| namespace spvtools { |
| namespace fuzz { |
| |
| TransformationReplaceOpPhiIdFromDeadPredecessor:: |
| TransformationReplaceOpPhiIdFromDeadPredecessor( |
| protobufs::TransformationReplaceOpPhiIdFromDeadPredecessor message) |
| : message_(std::move(message)) {} |
| |
| TransformationReplaceOpPhiIdFromDeadPredecessor:: |
| TransformationReplaceOpPhiIdFromDeadPredecessor(uint32_t opphi_id, |
| uint32_t pred_label_id, |
| uint32_t replacement_id) { |
| message_.set_opphi_id(opphi_id); |
| message_.set_pred_label_id(pred_label_id); |
| message_.set_replacement_id(replacement_id); |
| } |
| |
| bool TransformationReplaceOpPhiIdFromDeadPredecessor::IsApplicable( |
| opt::IRContext* ir_context, |
| const TransformationContext& transformation_context) const { |
| // |opphi_id| must be the id of an OpPhi instruction. |
| auto opphi_def = ir_context->get_def_use_mgr()->GetDef(message_.opphi_id()); |
| if (!opphi_def || opphi_def->opcode() != SpvOpPhi) { |
| return false; |
| } |
| |
| // |pred_label_id| must be the label id of a dead block. |
| auto pred_block = ir_context->get_instr_block(message_.pred_label_id()); |
| if (!pred_block || pred_block->id() != message_.pred_label_id() || |
| !transformation_context.GetFactManager()->BlockIsDead(pred_block->id())) { |
| return false; |
| } |
| |
| // |pred_label_id| must be one of the predecessors of the block containing the |
| // OpPhi instruction. |
| bool found = false; |
| for (auto pred : |
| ir_context->cfg()->preds(ir_context->get_instr_block(opphi_def)->id())) { |
| if (pred == message_.pred_label_id()) { |
| found = true; |
| break; |
| } |
| } |
| |
| if (!found) { |
| return false; |
| } |
| |
| // |replacement_id| must have the same type id as the OpPhi instruction. |
| auto replacement_def = |
| ir_context->get_def_use_mgr()->GetDef(message_.replacement_id()); |
| |
| if (!replacement_def || replacement_def->type_id() != opphi_def->type_id()) { |
| return false; |
| } |
| |
| // The replacement id must be available at the end of the predecessor. |
| return fuzzerutil::IdIsAvailableBeforeInstruction( |
| ir_context, pred_block->terminator(), replacement_def->result_id()); |
| } |
| |
| void TransformationReplaceOpPhiIdFromDeadPredecessor::Apply( |
| opt::IRContext* ir_context, |
| TransformationContext* /* transformation_context */) const { |
| // Get the OpPhi instruction. |
| auto opphi_def = ir_context->get_def_use_mgr()->GetDef(message_.opphi_id()); |
| |
| // Find the index corresponding to the operand being replaced and replace it, |
| // by looping through the odd-indexed input operands and finding |
| // |pred_label_id|. The index that we are interested in is the one before |
| // that. |
| for (uint32_t i = 1; i < opphi_def->NumInOperands(); i += 2) { |
| if (opphi_def->GetSingleWordInOperand(i) == message_.pred_label_id()) { |
| // The operand to be replaced is at index i-1. |
| opphi_def->SetInOperand(i - 1, {message_.replacement_id()}); |
| } |
| } |
| |
| // Invalidate the analyses because we have altered the usages of ids. |
| ir_context->InvalidateAnalysesExceptFor(opt::IRContext::kAnalysisNone); |
| } |
| |
| protobufs::Transformation |
| TransformationReplaceOpPhiIdFromDeadPredecessor::ToMessage() const { |
| protobufs::Transformation result; |
| *result.mutable_replace_opphi_id_from_dead_predecessor() = message_; |
| return result; |
| } |
| |
| std::unordered_set<uint32_t> |
| TransformationReplaceOpPhiIdFromDeadPredecessor::GetFreshIds() const { |
| return std::unordered_set<uint32_t>(); |
| } |
| |
| } // namespace fuzz |
| } // namespace spvtools |