source: src/ResolvExpr/Alternative.h @ aefcc3b

//
// Cforall Version 1.0.0 Copyright (C) 2015 University of Waterloo
//
// The contents of this file are covered under the licence agreement in the
// file "LICENCE" distributed with Cforall.
//
// Alternative.h --
//
// Author           : Richard C. Bilson
// Created On       : Sat May 16 23:45:43 2015
// Last Modified By : Peter A. Buhr
// Last Modified On : Sat May 16 23:54:39 2015
// Update Count     : 2
//

#ifndef ALTERNATIVE_H
#define ALTERNATIVE_H

#include <list>
#include "SynTree/SynTree.h"
#include "Cost.h"
#include "TypeEnvironment.h"

namespace ResolvExpr {
        struct Alternative;
        typedef std::list< Alternative > AltList;

        struct Alternative {
                Alternative();
                Alternative( Expression *expr, const TypeEnvironment &env, const Cost &cost );
                Alternative( Expression *expr, const TypeEnvironment &env, const Cost &cost, const Cost &cvtCost );
                Alternative( const Alternative &other );
                Alternative &operator=( const Alternative &other );
                Alternative( Alternative && other );
                Alternative &operator=( Alternative && other );
                ~Alternative();

                void initialize( const Alternative &src, Alternative &dest );

                void print( std::ostream &os, int indent = 0 ) const;

                Cost cost;
                Cost cvtCost;
                Expression *expr;
                TypeEnvironment env;
        };

        /// helper function used by explode
        template< typename OutputIterator >
        void explodeUnique( Expression * expr, const Alternative & alt, OutputIterator out ) {
                Type * res = expr->get_result();
                if ( TupleType * tupleType = dynamic_cast< TupleType * > ( res ) ) {
                        if ( TupleExpr * tupleExpr = dynamic_cast< TupleExpr * >( expr ) ) {
                                // can open tuple expr and dump its exploded components
                                for ( Expression * expr : tupleExpr->get_exprs() ) {
                                        explodeUnique( expr, alt, out );
                                }
                        } else {
                                // tuple type, but not tuple expr - need to refer to single instance of the argument
                                // expression and index into its components
                                UniqueExpr * unq = new UniqueExpr( expr->clone() );
                                for ( unsigned int i = 0; i < tupleType->size(); i++ ) {
                                        TupleIndexExpr * idx = new TupleIndexExpr( unq->clone(), i );
                                        explodeUnique( idx, alt, out );
                                        delete idx;
                                }
                                delete unq;
                        }
                } else {
                        // atomic (non-tuple) type - output a clone of the expression in a new alternative
                        *out++ = Alternative( expr->clone(), alt.env, alt.cost, alt.cvtCost );
                }
        }

        /// expands a tuple-valued alternative into multiple alternatives, each with a non-tuple-type
        template< typename OutputIterator >
        void explode( const Alternative &alt, OutputIterator out ) {
                explodeUnique( alt.expr, alt, out );
        }

        // explode list of alternatives
        template< typename OutputIterator >
        void explode( const AltList & alts, OutputIterator out ) {
                for ( const Alternative & alt : alts ) {
                        explode( alt, out );
                }
        }
} // namespace ResolvExpr

#endif // ALTERNATIVE_H

// Local Variables: //
// tab-width: 4 //
// mode: c++ //
// compile-command: "make install" //
// End: //