presto-main/src/main/java/io/prestosql/sql/gen/JoinCompiler.java/JoinCompiler/typeEquals
class JoinCompiler:    private static BytecodeNode typeEquals(
            BytecodeExpression type,
            BytecodeExpression leftBlock,
            BytecodeExpression leftBlockPosition,
            BytecodeExpression rightBlock,
            BytecodeExpression rightBlockPosition)
    {
        IfStatement ifStatement = new IfStatement();
        ifStatement.condition()
                .append(leftBlock.invoke("isNull", boolean.class, leftBlockPosition))
                .append(rightBlock.invoke("isNull", boolean.class, rightBlockPosition))
                .append(OpCode.IOR);

        ifStatement.ifTrue()
                .append(leftBlock.invoke("isNull", boolean.class, leftBlockPosition))
                .append(rightBlock.invoke("isNull", boolean.class, rightBlockPosition))
                .append(OpCode.IAND);

        ifStatement.ifFalse().append(typeEqualsIgnoreNulls(type, leftBlock, leftBlockPosition, rightBlock, rightBlockPosition));

        return ifStatement;
    }