1 // Copyright (c) 2017 Google Inc. 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #include "source/opt/compact_ids_pass.h" 16 17 #include <cassert> 18 #include <unordered_map> 19 20 #include "source/opt/ir_context.h" 21 22 namespace spvtools { 23 namespace opt { 24 Process()25Pass::Status CompactIdsPass::Process() { 26 bool modified = false; 27 std::unordered_map<uint32_t, uint32_t> result_id_mapping; 28 29 context()->module()->ForEachInst( 30 [&result_id_mapping, &modified](Instruction* inst) { 31 auto operand = inst->begin(); 32 while (operand != inst->end()) { 33 const auto type = operand->type; 34 if (spvIsIdType(type)) { 35 assert(operand->words.size() == 1); 36 uint32_t& id = operand->words[0]; 37 auto it = result_id_mapping.find(id); 38 if (it == result_id_mapping.end()) { 39 const uint32_t new_id = 40 static_cast<uint32_t>(result_id_mapping.size()) + 1; 41 const auto insertion_result = 42 result_id_mapping.emplace(id, new_id); 43 it = insertion_result.first; 44 assert(insertion_result.second); 45 } 46 if (id != it->second) { 47 modified = true; 48 id = it->second; 49 // Update data cached in the instruction object. 50 if (type == SPV_OPERAND_TYPE_RESULT_ID) { 51 inst->SetResultId(id); 52 } else if (type == SPV_OPERAND_TYPE_TYPE_ID) { 53 inst->SetResultType(id); 54 } 55 } 56 } 57 ++operand; 58 } 59 }, 60 true); 61 62 if (modified) 63 context()->module()->SetIdBound( 64 static_cast<uint32_t>(result_id_mapping.size() + 1)); 65 66 return modified ? Status::SuccessWithChange : Status::SuccessWithoutChange; 67 } 68 69 } // namespace opt 70 } // namespace spvtools 71