1 // Copyright (c) 2018 Google LLC
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/reduce/reduction_util.h"
16
17 #include "source/opt/ir_context.h"
18
19 namespace spvtools {
20 namespace reduce {
21
22 using namespace opt;
23
FindOrCreateGlobalUndef(IRContext * context,uint32_t type_id)24 uint32_t FindOrCreateGlobalUndef(IRContext* context, uint32_t type_id) {
25 for (auto& inst : context->module()->types_values()) {
26 if (inst.opcode() != SpvOpUndef) {
27 continue;
28 }
29 if (inst.type_id() == type_id) {
30 return inst.result_id();
31 }
32 }
33 // TODO(2182): this is adapted from MemPass::Type2Undef. In due course it
34 // would be good to factor out this duplication.
35 const uint32_t undef_id = context->TakeNextId();
36 std::unique_ptr<Instruction> undef_inst(
37 new Instruction(context, SpvOpUndef, type_id, undef_id, {}));
38 assert(undef_id == undef_inst->result_id());
39 context->module()->AddGlobalValue(std::move(undef_inst));
40 return undef_id;
41 }
42
43 } // namespace reduce
44 } // namespace spvtools
45