dawn-cmake/fuzzers/tint_spirv_tools_fuzzer/mutator_cache.cc

79 lines
2.2 KiB
C++

// Copyright 2021 The Tint Authors.
//
// 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 "fuzzers/tint_spirv_tools_fuzzer/mutator_cache.h"
namespace tint {
namespace fuzzers {
namespace spvtools_fuzzer {
MutatorCache::MutatorCache(size_t max_size)
: map_(), entries_(), max_size_(max_size) {
assert(max_size && "`max_size` may not be 0");
}
MutatorCache::Value::pointer MutatorCache::Get(const Key& key) {
auto it = map_.find(key);
if (it == map_.end()) {
return nullptr;
}
UpdateUsage(it);
return entries_.front().second.get();
}
void MutatorCache::Put(const Key& key, Value value) {
assert(value && "Mutator cache can't have nullptr unique_ptr");
auto it = map_.find(key);
if (it != map_.end()) {
it->second->second = std::move(value);
UpdateUsage(it);
} else {
if (map_.size() == max_size_) {
Remove(*entries_.back().first);
}
entries_.emplace_front(nullptr, std::move(value));
auto pair = map_.emplace(key, entries_.begin());
assert(pair.second && "The key must be unique");
entries_.front().first = &pair.first->first;
}
}
MutatorCache::Value MutatorCache::Remove(const Key& key) {
auto it = map_.find(key);
if (it == map_.end()) {
return nullptr;
}
auto result = std::move(it->second->second);
entries_.erase(it->second);
map_.erase(it);
return result;
}
size_t MutatorCache::KeyHash::operator()(
const std::vector<uint32_t>& vec) const {
return std::hash<std::u32string>()({vec.begin(), vec.end()});
}
void MutatorCache::UpdateUsage(Map::iterator it) {
auto entry = std::move(*it->second);
entries_.erase(it->second);
entries_.push_front(std::move(entry));
it->second = entries_.begin();
}
} // namespace spvtools_fuzzer
} // namespace fuzzers
} // namespace tint