io.trino.sql.ir.optimizer.rule.SimplifyStackedArithmeticNegation Maven / Gradle / Ivy
/*
* 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.
*/
package io.trino.sql.ir.optimizer.rule;
import io.trino.Session;
import io.trino.sql.ir.Call;
import io.trino.sql.ir.Expression;
import io.trino.sql.ir.optimizer.IrOptimizerRule;
import io.trino.sql.planner.Symbol;
import java.util.Map;
import java.util.Optional;
import static io.trino.metadata.GlobalFunctionCatalog.builtinFunctionName;
import static io.trino.spi.function.OperatorType.NEGATION;
/**
* Simplify stacked arithmetic negations expressions. E.g,
*
* - {@code $negation($negation(x)) -> x}
*
*/
public class SimplifyStackedArithmeticNegation
implements IrOptimizerRule
{
@Override
public Optional apply(Expression expression, Session session, Map bindings)
{
if (expression instanceof Call outer &&
outer.function().name().equals(builtinFunctionName(NEGATION)) &&
outer.arguments().getFirst() instanceof Call inner &&
inner.function().name().equals(builtinFunctionName(NEGATION))) {
return Optional.of(inner.arguments().getFirst());
}
return Optional.empty();
}
}