source: translator/ControlStruct/CaseRangeMutator.cc @ 42e2ad7

#include <list>
#include <cassert>
#include <cstdlib>
#include <iterator>

#include "utility.h"

#include "SynTree/Statement.h"
#include "SynTree/Expression.h"
#include "SynTree/Constant.h"
#include "SynTree/Type.h"
#include "CaseRangeMutator.h"

namespace ControlStruct {
    Statement *CaseRangeMutator::mutate(ChooseStmt *chooseStmt) {
        /* There shouldn't be any `choose' statements by now, throw an exception or something. */
        throw( 0 ) ; /* FIXME */
    }

    Statement *CaseRangeMutator::mutate(SwitchStmt *switchStmt) {
        std::list< Statement * > &cases = switchStmt->get_branches();

        // a `for' would be more natural... all this contortions are because `replace' invalidates the iterator
        std::list< Statement * >::iterator i = cases.begin();
        while (  i != cases.end() ) {
            (*i)->acceptMutator( *this );

            if ( ! newCaseLabels.empty() ) {
                std::list< Statement * > newCases;

                // transform( newCaseLabels.begin(), newCaseLabels.end(), bnd1st( ptr_fun( ctor< CaseStmt, Label, Expression * > ) ) );

                for ( std::list< Expression * >::iterator j = newCaseLabels.begin();
                      j != newCaseLabels.end(); j++ ) {
                    std::list<Label> emptyLabels;
                    std::list< Statement *> emptyStmts;
                    newCases.push_back( new CaseStmt( emptyLabels, *j, emptyStmts ) );
                }

                if ( CaseStmt *currentCase = dynamic_cast< CaseStmt * > ( *i ) )
                    if ( ! currentCase->get_statements().empty() ) {
                        CaseStmt *lastCase = dynamic_cast< CaseStmt * > ( newCases.back() );
                        if ( lastCase == 0 ) { throw ( 0 ); /* FIXME */ } // something is very wrong, as I just made these, and they were all cases
                        // transfer the statement block (if any) to the new list:
                        lastCase->set_statements( currentCase->get_statements() );
                    }
                std::list< Statement * >::iterator j = i; advance( j, 1 );
                replace ( cases, i, newCases );
                i = j;
                newCaseLabels.clear();
            } else
                i++;
        } // while

        return switchStmt;
    }

    Statement *CaseRangeMutator::mutate(FallthruStmt *fallthruStmt) {
        //delete fallthruStmt;
        return new NullStmt();
    }

    Statement *CaseRangeMutator::mutate(CaseStmt *caseStmt) {
        UntypedExpr *cond;
        if ( (cond = dynamic_cast< UntypedExpr * >( caseStmt->get_condition() )) != 0 ) {
            NameExpr *nmfunc;
            if ( (nmfunc = dynamic_cast< NameExpr *>( cond->get_function() )) != 0 ) {
                if ( nmfunc->get_name() == std::string("Range") ) {
                    assert( cond->get_args().size() == 2 );
                    std::list<Expression *>::iterator i = cond->get_args().begin();
                    Expression *lo = *i, *hi = *(++i); // "unnecessary" temporaries
                    fillRange( lo, hi);
                }
            }
        } else if ( TupleExpr *tcond = dynamic_cast< TupleExpr * >( caseStmt->get_condition() ) ) {
            // case list
            assert( ! tcond->get_exprs().empty() );
            for ( std::list< Expression * >::iterator i = tcond->get_exprs().begin(); i != tcond->get_exprs().end(); i++ )
                newCaseLabels.push_back( *i ); // do I need to clone them?
        } // if

        std::list< Statement * > &stmts = caseStmt->get_statements();
        mutateAll ( stmts, *this );

        return caseStmt;
    }

    void CaseRangeMutator::fillRange(Expression *lo, Expression *hi) {
        // generate the actual range (and check for consistency)
        Constant *c_lo, *c_hi;
        ConstantExpr *ce_lo, *ce_hi;
        ce_lo = dynamic_cast< ConstantExpr * >( lo );
        ce_hi = dynamic_cast< ConstantExpr * >( hi );

        if ( ce_lo && ce_hi ) {
            c_lo = ce_lo->get_constant(); c_hi = ce_hi->get_constant();
        } /* else {
             if ( ! ce_lo ) ;
             if ( ! ce_hi ) ;
             } */
        BasicType *ty_lo = dynamic_cast< BasicType * >( c_lo->get_type() ),
            *ty_hi = dynamic_cast< BasicType * >( c_hi->get_type() );
    
        if ( ! ty_lo || ! ty_hi )
            return; // one of them is not a constant

        switch ( ty_lo->get_kind() ) {
          case BasicType::Char:
          case BasicType::UnsignedChar:
            switch ( ty_hi->get_kind() ){
                  case BasicType::Char:
                  case BasicType::UnsignedChar:
                    // first case, they are both printable ASCII characters represented as 'x'
                    if ( c_lo->get_value().size() == 3 && c_hi->get_value().size() == 3 ) {
                        char ch_lo = (c_lo->get_value())[1], ch_hi = (c_hi->get_value())[1];

                        if ( ch_lo > ch_hi ) { char t=ch_lo; ch_lo=ch_hi; ch_hi=t; }

                        for( char c = ch_lo; c <=  ch_hi; c++ ){
                            Type::Qualifiers q;
                            Constant cnst( new BasicType(q, BasicType::Char),
                                           std::string("'") + c + std::string("'") );
                            newCaseLabels.push_back( new ConstantExpr( cnst ) );
                        }

                        return;
                    }
                    break;
                  default:
                    // error: incompatible constants
                    break;
                }
            break;
          case BasicType::ShortSignedInt:
          case BasicType::ShortUnsignedInt:
          case BasicType::SignedInt:
          case BasicType::UnsignedInt:
          case BasicType::LongSignedInt:
          case BasicType::LongUnsignedInt:
          case BasicType::LongLongSignedInt:
          case BasicType::LongLongUnsignedInt:
            switch ( ty_hi->get_kind() ) {
              case BasicType::ShortSignedInt:
              case BasicType::ShortUnsignedInt:
              case BasicType::SignedInt:
              case BasicType::UnsignedInt:
              case BasicType::LongSignedInt:
              case BasicType::LongUnsignedInt:
              case BasicType::LongLongSignedInt:
              case BasicType::LongLongUnsignedInt: {
                  int i_lo = atoi(c_lo->get_value().c_str()),
                      i_hi = atoi(c_hi->get_value().c_str());

                  if ( i_lo > i_hi ) { int t=i_lo; i_lo=i_hi; i_hi=t; }

                  for( int c = i_lo; c <=  i_hi; c++ ){
                      Type::Qualifiers q;
                      Constant cnst( new BasicType(q, ty_hi->get_kind()), // figure can't hurt (used to think in positives)
                                     toString< int >( c ) );
                      newCaseLabels.push_back( new ConstantExpr( cnst ) );
                  }

                  return;
              }
              default:
                // error: incompatible constants
                break;
            }
            break;
          default:
            break;
        } // switch

        /* End: */{ 
            // invalid range, signal a warning (it still generates the two case labels)
            newCaseLabels.push_back( lo );
            newCaseLabels.push_back( hi );
            return;
        }
    }
} // namespace ControlStruct