/*

  $Id$

  Copyright 1989-2016 MINES ParisTech

  This file is part of PIPS.

  PIPS is free software: you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  any later version.

  PIPS 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 General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with PIPS.  If not, see <http://www.gnu.org/licenses/>.

*/
#ifdef HAVE_CONFIG_H
    #include "pips_config.h"
#endif
/* package convex effects :  Be'atrice Creusillet 6/97
 *
 * File: compose.c
 * ~~~~~~~~~~~~~~~
 *
 * This File contains the intanciation of the generic functions necessary
 * for the composition of convex effects with transformers or preconditions
 *
 */

#include <stdio.h>
#include <string.h>

#include "genC.h"
#include "linear.h"
#include "ri.h"
#include "effects.h"
#include "ri-util.h"
#include "prettyprint.h" // for sc_syst_debug()
#include "effects-util.h"
#include "misc.h"

#include "transformer.h"
#include "effects-generic.h"
#include "effects-convex.h"

list
convex_regions_transformer_compose(list l_reg, transformer trans)
{
    project_regions_with_transformer_inverse(l_reg, trans, NIL);
    return l_reg;
}

list
convex_regions_inverse_transformer_compose(list l_reg, transformer trans)
{
    project_regions_with_transformer(l_reg, trans, NIL);
    return l_reg;
}

list convex_regions_precondition_compose(list l_reg, transformer context, bool on_scalar_p)
{
  list l_res = NIL;
  Psysteme sc_context = predicate_system(transformer_relation(context));

  pips_assert("sc is weakly consistent", sc_weak_consistent_p(sc_context));
  ifdebug(8) {
    pips_debug(8, "context: \n");
    sc_syst_debug(sc_context);
  }

  FOREACH(EFFECT, reg, l_reg) {
    /* Only the store effects require preconditions */
    if(store_effect_p(reg)) {
      /* FI: this leads to problems when the context might become
       *     later empty: there won't be any way to find out; in one
       *     case I do not remember, the IN regions end up wrong;
       *     however, adding descriptors for all scalar references may
       *     slow down the region computation a lot. */
      /* NL: To have good (IN/) OUT-Regions for (loop/) loop body in presence of scalar,
       *     We have to add the the context (loop bounds) for the regions too.
       *     To make a compromise between performance and requirement,
       *     add variable on_scalar_p
       */
      if (on_scalar_p || !effect_scalar_p(reg) )
      {
        descriptor reg_d = effect_descriptor(reg);
        Psysteme reg_sc = descriptor_convex_p(reg_d)? descriptor_convex(reg_d) : NULL;

        pips_assert("sc_context is weakly consistent", sc_weak_consistent_p(sc_context));
        pips_assert("reg_sc is weakly consistent (1)", sc_weak_consistent_p(reg_sc));
        region_sc_append(reg, sc_context, false);

        /* remove potential old values that may be found in precondition */
        list l_old_values = NIL;
        reg_sc = region_system(reg);
        for(Pbase b = sc_base(reg_sc); !BASE_NULLE_P(b); b = vecteur_succ(b)) {
          entity e = (entity) vecteur_var(b);
          if(global_old_value_p(e)) {
            l_old_values = CONS(ENTITY, e, l_old_values);
          }
        }
        region_exact_projection_along_parameters(reg, l_old_values);
        reg_sc = region_system(reg);
        gen_free_list(l_old_values);
        debug_region_consistency(reg);
        pips_debug_effect(8, "region after transformation: \n", reg );

        pips_assert("sc_context is weakly consistent", sc_weak_consistent_p(sc_context));
        pips_assert("reg_sc is weakly consistent (2)", sc_weak_consistent_p(reg_sc));
      }

      if (!region_empty_p(reg))
        l_res = CONS(EFFECT, reg, l_res);
    }
  }

  return l_res;
}