/************************************************************************
 ************************************************************************
    FAUST compiler
    Copyright (C) 2003-2018 GRAME, Centre National de Creation Musicale
    ---------------------------------------------------------------------
    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU Lesser General Public License as published by
    the Free Software Foundation; either version 2.1 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 ************************************************************************
 ************************************************************************/

#ifndef _LOOP_H
#define _LOOP_H

/**********************************************************************
        - loop.hh : loop C++ to be filled (projet FAUST) -

        Historique :
        -----------
        21-01-2008 : initial implementation (YO)

***********************************************************************/

#include <list>
#include <map>
#include <set>
#include <stack>
#include <string>

#include "statement.hh"
#include "tlib.hh"

using namespace std;

/*
 * Loops are lines of code that correspond to a recursive expression or a vector expression.
 */

struct Loop {
    const bool   fIsRecursive;    ///< recursive loops can't be SIMDed
    Tree         fRecSymbolSet;   ///< recursive loops define a set of recursive symbol
    Loop* const  fEnclosingLoop;  ///< Loop from which this one originated
    const string fSize;           ///< number of iterations of the loop
    // fields concerned by absorbsion
    set<Loop*>      fBackwardLoopDependencies;  ///< Loops that must be computed before this one
    set<Loop*>      fForwardLoopDependencies;   ///< Loops that will be computed after this one
    list<Statement> fPreCode;                   ///< code to execute at the begin of the loop
    list<Statement> fExecCode;                  ///< code to execute in the loop
    list<Statement> fPostCode;                  ///< code to execute at the end of the loop
    // for topological sort
    int fOrder;  ///< used during topological sort
    int fIndex;  ///< used during scheduler mode code generation
    // new fields
    int         fUseCount;    ///< how many loops depend on this one
    list<Loop*> fExtraLoops;  ///< extra loops that where in sequences

    int fPrinted;  ///< true when loop has been printed (to track multi-print errors)

   public:
    Loop(Tree recsymbol, Loop* encl, const string& size);  ///< create a recursive loop
    Loop(Loop* encl, const string& size);                  ///< create a non recursive loop

    bool isEmpty();                   ///< true when the loop doesn't contain any line of code
    bool hasRecDependencyIn(Tree S);  ///< returns true is this loop or its ancestors define a symbol in S

    void addPreCode(const Statement& str);      ///< add a line of C++ code pre code
    void addExecCode(const Statement& str);     ///< add a line of C++ code
    void addPostCode(const Statement& str);     ///< add a line of C++ post code
    void println(int n, ostream& fout);         ///< print the loop
    void printParLoopln(int n, ostream& fout);  ///< print the loop with a #pragma omp loop

    void printoneln(int n, ostream& fout);  ///< print the loop in scalar mode

    void absorb(Loop* l);  ///< absorb a loop inside this one
    // new method
    void concat(Loop* l);
};

#endif
