source: src/Tuples/MultRet.cc @ ecb1534

//
// 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.
//
// MultRet.cc -- 
//
// Author           : Rodolfo G. Esteves
// Created On       : Mon May 18 07:44:20 2015
// Last Modified By : Peter A. Buhr
// Last Modified On : Mon May 18 12:37:57 2015
// Update Count     : 1
//

#include <list>
#include <vector>
#include <cassert>
#include <algorithm>

#include "MultRet.h"
#include "SynTree/Statement.h"
#include "SynTree/Expression.h"
#include "SynTree/Declaration.h"
#include "SynTree/Type.h"

namespace Tuples {
        MVRMutator::MVRMutator() : newVars( 0 ), newCode( 0 ) {
        }

        MVRMutator::~MVRMutator() {
        }

        int MVRMutator::curVal = 0;

        Statement *MVRMutator::mutate( ExprStmt *exprStmt ) {
                MVRMutator toplevel;
                exprStmt->set_expr( maybeMutate( exprStmt->get_expr(), toplevel ) );

                if ( toplevel.hasCode() ) {
                        assert ( toplevel.getVars() != 0 );

                        typedef std::list<Statement *> Statements;

                        CompoundStmt *code = new CompoundStmt( std::list< Label >() );

                        // copy variables
                        Statements &vars = toplevel.getVars()->get_kids();
                        for ( Statements::iterator i = vars.begin(); i != vars.end(); i++ )
                                code->get_kids().push_back( *i );

                        // copy statements
                        Statements &block = toplevel.getCode()->get_kids();
                        for ( Statements::iterator i = block.begin(); i != block.end(); i++ )
                                code->get_kids().push_back( *i );

                        return code;
                } else
                        return exprStmt;
        }

        Expression *MVRMutator::mutate( ApplicationExpr *appExpr ) {
                // appExpr->set_function(  maybeMutate( appExpr->get_function(), *this ) );
                bool mulretp = false;
                VariableExpr *funname;
                if ( (funname = dynamic_cast<VariableExpr *>(appExpr->get_function())) == 0 ) goto DoArgs;

                FunctionDecl *fundecl;
                if ((fundecl = dynamic_cast<FunctionDecl *>(funname->get_var())) == 0) goto DoArgs;
                {
                        typedef std::list<DeclarationWithType*> RetType;

                        RetType &rets = fundecl->get_functionType()->get_returnVals();
                        if ( rets.size() <= 1 ) goto DoArgs;
                        mulretp = true;

                        if ( newVars == 0 )
                                newVars = new CompoundStmt( std::list<Label>(0) );

                        for (RetType::iterator i = rets.begin() ; i != rets.end(); i++) {
                                DeclStmt *arg = newVar( *i );
                                newVars->get_kids().push_back( arg );
                                add_pending( arg->get_decl() );
                        } // for
                }

          DoArgs:
                // mutate the argument list
                typedef std::list< Expression *> Exprs;
                Exprs &args = appExpr->get_args();
                std::list< Expression * > newArgs;
                for ( Exprs::iterator i = args.begin(); i != args.end(); i++ ) {
                        MVRMutator next;
                        Expression *mutated = (*i)->acceptMutator( next );

                        if ( next.hasCode() ) {
                                // merge new vars and bodies
                                typedef std::list< Statement * > Stmts;
                                Stmts &vars = next.getVars()->get_kids();
                                Stmts &block = next.getCode()->get_kids();

                                if (newVars == 0)
                                        newVars = new CompoundStmt( std::list< Label >() );
                                for ( Stmts::iterator i = vars.begin(); i != vars.end(); i++ )  // std::splice? -- need to append lists
                                        newVars->get_kids().push_back( *i );

                                if (newCode == 0)
                                        newCode = new CompoundStmt( std::list< Label >() );
                                for ( Stmts::iterator i = block.begin(); i != block.end(); i++ )
                                        newCode->get_kids().push_back( *i );
                        } // if

                        if ( next.hasResults() ) {
                                Exprs &res = next.get_results();
                                for ( Exprs::iterator i = res.begin(); i != res.end(); i++ )
                                        newArgs.push_back( *i );
                        } else
                                newArgs.push_back( mutated );
                }

                appExpr->get_args() = newArgs;  // new argument list

                if ( mulretp ) {
                        // add 'out' parameters
                        if ( ! argsToAdd.empty() )
                                for (std::list< Expression *>::iterator i = argsToAdd.begin(); i != argsToAdd.end(); i++)
                                        (appExpr->get_args()).push_back( *i );
                        // clear 'out' parameters ( so that the list can be reused -- substitute by auto_ptr later? )

                        if (newCode == 0)
                                newCode = new CompoundStmt( std::list<Label>(0) );
                } // if

                // add to block of code
                if ( newCode != 0 )
                        newCode->get_kids().push_back( new ExprStmt( std::list<Label>(), appExpr ) );

                return appExpr;
        }

        // Auxiliary function to generate new names for the `output' parameters
        DeclStmt *MVRMutator::newVar( DeclarationWithType *reqDecl ) {
                // std::ostrstream os;
                // os << "__" << curVal++ << "__";// << std::ends;
                // os.freeze( false );

                ObjectDecl *decl;
                if ((decl = dynamic_cast<ObjectDecl *>( reqDecl )) != 0)
                        // return new DeclStmt( new ObjectDecl( std::string (os.str(), os.pcount()), );
                        return new DeclStmt( std::list<Label>(), decl );
                else
                        return 0;
        }

        void MVRMutator::add_pending( Declaration *decl ) {
                ObjectDecl *obj;
                if ( (obj = dynamic_cast< ObjectDecl * >( decl )) == 0 ) return;

                VariableExpr *var = new VariableExpr(obj, 0 );
                results.push_back( var ); // probably change this name to newResults or something
                argsToAdd.push_back( new AddressExpr( var ) );
                return;
        }
}

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