1 // Copyright (c) 2019 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/opt/strip_atomic_counter_memory_pass.h"
16 #include "source/opt/ir_context.h"
17 
18 namespace spvtools {
19 namespace opt {
20 
Process()21 Pass::Status StripAtomicCounterMemoryPass::Process() {
22   bool changed = false;
23   context()->module()->ForEachInst([this, &changed](Instruction* inst) {
24     auto indices = spvOpcodeMemorySemanticsOperandIndices(inst->opcode());
25     if (indices.empty()) return;
26 
27     for (auto idx : indices) {
28       auto mem_sem_id = inst->GetSingleWordOperand(idx);
29       const auto& mem_sem_inst =
30           context()->get_def_use_mgr()->GetDef(mem_sem_id);
31       // The spec explicitly says that this id must be an OpConstant
32       auto mem_sem_val = mem_sem_inst->GetSingleWordOperand(2);
33       if (!(mem_sem_val & SpvMemorySemanticsAtomicCounterMemoryMask)) {
34         continue;
35       }
36       mem_sem_val &= ~SpvMemorySemanticsAtomicCounterMemoryMask;
37 
38       analysis::Integer int_type(32, false);
39       const analysis::Type* uint32_type =
40           context()->get_type_mgr()->GetRegisteredType(&int_type);
41       auto* new_const = context()->get_constant_mgr()->GetConstant(
42           uint32_type, {mem_sem_val});
43       auto* new_const_inst =
44           context()->get_constant_mgr()->GetDefiningInstruction(new_const);
45       auto new_const_id = new_const_inst->result_id();
46 
47       inst->SetOperand(idx, {new_const_id});
48       context()->UpdateDefUse(inst);
49       changed = true;
50     }
51   });
52 
53   return changed ? Status::SuccessWithChange : Status::SuccessWithoutChange;
54 }
55 
56 }  // namespace opt
57 }  // namespace spvtools
58