source: translator/ControlStruct/CaseRangeMutator.cc @ 134b86a

#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++;
    }

    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?
    }

    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;
    }

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

} // namespace ControlStruct