private Operator genLateralViewPlanForDest(String dest, QB qb, Operator op)
      throws SemanticException {
    ASTNode lateralViewTree = qb.getParseInfo().getDestToLateralView().get(dest);
    if (lateralViewTree != null) {
      return genLateralViewPlan(qb, op, lateralViewTree);
    }
    return op;
  }
Generates the operator DAG needed to implement lateral views and attaches
it to the TS operator.

@param aliasToOpInfo
         A mapping from a table alias to the TS operator. This function
         replaces the operator mapping as necessary
@param qb
@throws SemanticException
ql/src/java/org/apache/hadoop/hive/ql/parse/SemanticAnalyzer.java