dawn-cmake/fuzzers/tint_ast_fuzzer/mutation_finders/replace_identifiers.cc

80 lines
2.5 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_ast_fuzzer/mutation_finders/replace_identifiers.h"
#include <memory>
#include "fuzzers/tint_ast_fuzzer/mutations/replace_identifier.h"
#include "fuzzers/tint_ast_fuzzer/util.h"
#include "src/sem/expression.h"
#include "src/sem/statement.h"
#include "src/sem/variable.h"
namespace tint {
namespace fuzzers {
namespace ast_fuzzer {
MutationList MutationFinderReplaceIdentifiers::FindMutations(
const tint::Program& program,
NodeIdMap* node_id_map,
ProbabilityContext* probability_context) const {
MutationList result;
// Go through each variable in the AST and for each user of that variable, try
// to replace it with some other variable usage.
for (const auto* node : program.SemNodes().Objects()) {
const auto* sem_variable = tint::As<sem::Variable>(node);
if (!sem_variable) {
continue;
}
// Iterate over all users of `sem_variable`.
for (const auto* user : sem_variable->Users()) {
// Get all variables that can be used to replace the `user` of
// `sem_variable`.
auto candidate_variables = util::GetAllVarsInScope(
program, user->Stmt(), [user](const sem::Variable* var) {
return var != user->Variable() && var->Type() == user->Type();
});
if (candidate_variables.empty()) {
// No suitable replacements have been found.
continue;
}
const auto* replacement =
candidate_variables[probability_context->GetRandomIndex(
candidate_variables)];
result.push_back(std::make_unique<MutationReplaceIdentifier>(
node_id_map->GetId(user->Declaration()),
node_id_map->GetId(replacement->Declaration())));
}
}
return result;
}
uint32_t MutationFinderReplaceIdentifiers::GetChanceOfApplyingMutation(
ProbabilityContext* probability_context) const {
return probability_context->GetChanceOfReplacingIdentifiers();
}
} // namespace ast_fuzzer
} // namespace fuzzers
} // namespace tint