/*
* 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 com.facebook.presto.sql.gen;
import com.facebook.presto.bytecode.BytecodeBlock;
import com.facebook.presto.bytecode.BytecodeNode;
import com.facebook.presto.bytecode.Scope;
import com.facebook.presto.bytecode.Variable;
import com.facebook.presto.bytecode.control.IfStatement;
import com.facebook.presto.metadata.Signature;
import com.facebook.presto.spi.block.Block;
import com.facebook.presto.spi.block.BlockBuilder;
import com.facebook.presto.spi.block.BlockBuilderStatus;
import com.facebook.presto.spi.block.InterleavedBlockBuilder;
import com.facebook.presto.spi.type.Type;
import com.facebook.presto.sql.relational.RowExpression;
import java.util.List;
import static com.facebook.presto.bytecode.expression.BytecodeExpressions.constantFalse;
import static com.facebook.presto.bytecode.expression.BytecodeExpressions.constantInt;
import static com.facebook.presto.bytecode.expression.BytecodeExpressions.newInstance;
import static com.facebook.presto.sql.gen.BytecodeUtils.loadConstant;
import static com.facebook.presto.sql.gen.SqlTypeBytecodeExpression.constantType;
public class RowConstructorCodeGenerator
implements BytecodeGenerator
{
@Override
public BytecodeNode generateExpression(Signature signature, BytecodeGeneratorContext context, Type rowType, List<RowExpression> arguments)
{
BytecodeBlock block = new BytecodeBlock().setDescription("Constructor for " + rowType.toString());
CallSiteBinder binder = context.getCallSiteBinder();
Scope scope = context.getScope();
List<Type> types = rowType.getTypeParameters();
block.comment("BlockBuilder blockBuilder = new InterleavedBlockBuilder(types, new BlockBuilderStatus(), 1);");
Variable blockBuilder = scope.createTempVariable(BlockBuilder.class);
Binding typesBinding = binder.bind(types, List.class);
block.append(blockBuilder.set(
newInstance(InterleavedBlockBuilder.class, loadConstant(typesBinding), newInstance(BlockBuilderStatus.class), constantInt(1))));
for (int i = 0; i < arguments.size(); ++i) {
Type fieldType = types.get(i);
Class<?> javaType = fieldType.getJavaType();
if (javaType == void.class) {
block.comment(i + "-th field type of row is undefined");
block.append(blockBuilder.invoke("appendNull", BlockBuilder.class).pop());
}
else {
Variable field = scope.createTempVariable(javaType);
block.comment("Clean wasNull and Generate + " + i + "-th field of row");
block.append(context.wasNull().set(constantFalse()));
block.append(context.generate(arguments.get(i)));
block.putVariable(field);
block.append(new IfStatement()
.condition(context.wasNull())
.ifTrue(blockBuilder.invoke("appendNull", BlockBuilder.class).pop())
.ifFalse(constantType(binder, fieldType).writeValue(blockBuilder, field).pop()));
}
}
block.comment("put (Block) blockBuilder.build(); wasNull = false;");
block.append(blockBuilder.invoke("build", Block.class));
block.append(context.wasNull().set(constantFalse()));
return block;
}
}