[PATCH 20/20] disable loop flattening

[Sebastian Pop <sebpop at gmail dot com>]

---
 gcc/graphite-flattening.c |  289 +--------------------------------------------
 1 files changed, 4 insertions(+), 285 deletions(-)

diff --git a/gcc/graphite-flattening.c b/gcc/graphite-flattening.c
index c58d8a3..c8c8531 100644
--- a/gcc/graphite-flattening.c
+++ b/gcc/graphite-flattening.c
@@ -145,297 +145,16 @@ along with GCC; see the file COPYING3.  If not see
    At each step, the iteration domain of the outer loop is enlarged to
    contain enough points to iterate over the inner loop domain.  */
 
-/* Initializes RES to the number of iterations of the linearized loop
-   LST.  RES is the cardinal of the iteration domain of LST.  */
-
-static void
-lst_linearized_niter (lst_p lst, mpz_t res)
-{
-  int i;
-  lst_p l;
-  mpz_t n;
-
-  mpz_init (n);
-  mpz_set_si (res, 0);
-
-  FOR_EACH_VEC_ELT (lst_p, LST_SEQ (lst), i, l)
-    if (LST_LOOP_P (l))
-      {
-	lst_linearized_niter (l, n);
-	mpz_add (res, res, n);
-      }
-
-  if (LST_LOOP_P (lst))
-    {
-      lst_niter_for_loop (lst, n);
-
-      if (mpz_cmp_si (res, 0) != 0)
-	mpz_mul (res, res, n);
-      else
-	mpz_set (res, n);
-    }
-
-  mpz_clear (n);
-}
-
-/* Applies the translation "f (x) = x + OFFSET" to the loop containing
-   STMT.  */
-
-static void
-lst_offset (lst_p stmt, mpz_t offset)
-{
-  lst_p inner = LST_LOOP_FATHER (stmt);
-  poly_bb_p pbb = LST_PBB (stmt);
-  ppl_Polyhedron_t poly = PBB_TRANSFORMED_SCATTERING (pbb);
-  int inner_depth = lst_depth (inner);
-  ppl_dimension_type inner_dim = psct_dynamic_dim (pbb, inner_depth);
-  ppl_Linear_Expression_t expr;
-  ppl_dimension_type dim;
-  ppl_Coefficient_t one;
-  mpz_t x;
-
-  mpz_init (x);
-  mpz_set_si (x, 1);
-  ppl_new_Coefficient (&one);
-  ppl_assign_Coefficient_from_mpz_t (one, x);
-
-  ppl_Polyhedron_space_dimension (poly, &dim);
-  ppl_new_Linear_Expression_with_dimension (&expr, dim);
-
-  ppl_set_coef (expr, inner_dim, 1);
-  ppl_set_inhomogeneous_gmp (expr, offset);
-  ppl_Polyhedron_affine_image (poly, inner_dim, expr, one);
-  ppl_delete_Linear_Expression (expr);
-  ppl_delete_Coefficient (one);
-}
-
-/* Scale by FACTOR the loop LST containing STMT.  */
-
-static void
-lst_scale (lst_p lst, lst_p stmt, mpz_t factor)
-{
-  mpz_t x;
-  ppl_Coefficient_t one;
-  int outer_depth = lst_depth (lst);
-  poly_bb_p pbb = LST_PBB (stmt);
-  ppl_Polyhedron_t poly = PBB_TRANSFORMED_SCATTERING (pbb);
-  ppl_dimension_type outer_dim = psct_dynamic_dim (pbb, outer_depth);
-  ppl_Linear_Expression_t expr;
-  ppl_dimension_type dim;
-
-  mpz_init (x);
-  mpz_set_si (x, 1);
-  ppl_new_Coefficient (&one);
-  ppl_assign_Coefficient_from_mpz_t (one, x);
-
-  ppl_Polyhedron_space_dimension (poly, &dim);
-  ppl_new_Linear_Expression_with_dimension (&expr, dim);
-
-  /* outer_dim = factor * outer_dim.  */
-  ppl_set_coef_gmp (expr, outer_dim, factor);
-  ppl_Polyhedron_affine_image (poly, outer_dim, expr, one);
-  ppl_delete_Linear_Expression (expr);
-
-  mpz_clear (x);
-  ppl_delete_Coefficient (one);
-}
-
-/* Project the INNER loop into the iteration domain of the OUTER loop.
-   STRIDE is the number of iterations between two iterations of the
-   outer loop.  */
-
-static void
-lst_project_loop (lst_p outer, lst_p inner, mpz_t stride)
-{
-  int i;
-  lst_p stmt;
-  mpz_t x;
-  ppl_Coefficient_t one;
-  int outer_depth = lst_depth (outer);
-  int inner_depth = lst_depth (inner);
-
-  mpz_init (x);
-  mpz_set_si (x, 1);
-  ppl_new_Coefficient (&one);
-  ppl_assign_Coefficient_from_mpz_t (one, x);
-
-  FOR_EACH_VEC_ELT (lst_p, LST_SEQ (inner), i, stmt)
-    {
-      poly_bb_p pbb = LST_PBB (stmt);
-      ppl_Polyhedron_t poly = PBB_TRANSFORMED_SCATTERING (pbb);
-      ppl_dimension_type outer_dim = psct_dynamic_dim (pbb, outer_depth);
-      ppl_dimension_type inner_dim = psct_dynamic_dim (pbb, inner_depth);
-      ppl_Linear_Expression_t expr;
-      ppl_dimension_type dim;
-      ppl_dimension_type *ds;
-
-      /* There should be no loops under INNER.  */
-      gcc_assert (!LST_LOOP_P (stmt));
-      ppl_Polyhedron_space_dimension (poly, &dim);
-      ppl_new_Linear_Expression_with_dimension (&expr, dim);
-
-      /* outer_dim = outer_dim * stride + inner_dim.  */
-      ppl_set_coef (expr, inner_dim, 1);
-      ppl_set_coef_gmp (expr, outer_dim, stride);
-      ppl_Polyhedron_affine_image (poly, outer_dim, expr, one);
-      ppl_delete_Linear_Expression (expr);
-
-      /* Project on inner_dim.  */
-      ppl_new_Linear_Expression_with_dimension (&expr, dim - 1);
-      ppl_Polyhedron_affine_image (poly, inner_dim, expr, one);
-      ppl_delete_Linear_Expression (expr);
-
-      /* Remove inner loop and the static schedule of its body.  */
-      ds = XNEWVEC (ppl_dimension_type, 2);
-      ds[0] = inner_dim;
-      ds[1] = inner_dim + 1;
-      ppl_Polyhedron_remove_space_dimensions (poly, ds, 2);
-      PBB_NB_SCATTERING_TRANSFORM (pbb) -= 2;
-      free (ds);
-    }
-
-  mpz_clear (x);
-  ppl_delete_Coefficient (one);
-}
-
-/* Flattens the loop nest LST.  Return true when something changed.
-   OFFSET is used to compute the number of iterations of the outermost
-   loop before the current LST is executed.  */
-
-static bool
-lst_flatten_loop (lst_p lst, mpz_t init_offset)
-{
-  int i;
-  lst_p l;
-  bool res = false;
-  mpz_t n, one, offset, stride;
-
-  mpz_init (n);
-  mpz_init (one);
-  mpz_init (offset);
-  mpz_init (stride);
-  mpz_set (offset, init_offset);
-  mpz_set_si (one, 1);
-
-  lst_linearized_niter (lst, stride);
-  lst_niter_for_loop (lst, n);
-  mpz_tdiv_q (stride, stride, n);
-
-  FOR_EACH_VEC_ELT (lst_p, LST_SEQ (lst), i, l)
-    if (LST_LOOP_P (l))
-      {
-	res = true;
-
-	lst_flatten_loop (l, offset);
-	lst_niter_for_loop (l, n);
-
-	lst_project_loop (lst, l, stride);
-
-	/* The offset is the number of iterations minus 1, as we want
-	   to execute the next statements at the same iteration as the
-	   last iteration of the loop.  */
-	mpz_sub (n, n, one);
-	mpz_add (offset, offset, n);
-      }
-    else
-      {
-	lst_scale (lst, l, stride);
-	if (mpz_cmp_si (offset, 0) != 0)
-	  lst_offset (l, offset);
-      }
-
-  FOR_EACH_VEC_ELT (lst_p, LST_SEQ (lst), i, l)
-    if (LST_LOOP_P (l))
-      lst_remove_loop_and_inline_stmts_in_loop_father (l);
-
-  mpz_clear (n);
-  mpz_clear (one);
-  mpz_clear (offset);
-  mpz_clear (stride);
-  return res;
-}
-
-/* Remove all but the first 3 dimensions of the scattering:
-   - dim0: the static schedule for the loop
-   - dim1: the dynamic schedule of the loop
-   - dim2: the static schedule for the loop body.  */
-
-static void
-remove_unused_scattering_dimensions (lst_p lst)
-{
-  int i;
-  lst_p stmt;
-  mpz_t x;
-  ppl_Coefficient_t one;
-
-  mpz_init (x);
-  mpz_set_si (x, 1);
-  ppl_new_Coefficient (&one);
-  ppl_assign_Coefficient_from_mpz_t (one, x);
-
-  FOR_EACH_VEC_ELT (lst_p, LST_SEQ (lst), i, stmt)
-    {
-      poly_bb_p pbb = LST_PBB (stmt);
-      ppl_Polyhedron_t poly = PBB_TRANSFORMED_SCATTERING (pbb);
-      int j, nb_dims_to_remove = PBB_NB_SCATTERING_TRANSFORM (pbb) - 3;
-      ppl_dimension_type *ds;
-
-      /* There should be no loops inside LST after flattening.  */
-      gcc_assert (!LST_LOOP_P (stmt));
-
-      if (!nb_dims_to_remove)
-	continue;
-
-      ds = XNEWVEC (ppl_dimension_type, nb_dims_to_remove);
-      for (j = 0; j < nb_dims_to_remove; j++)
-	ds[j] = j + 3;
-
-      ppl_Polyhedron_remove_space_dimensions (poly, ds, nb_dims_to_remove);
-      PBB_NB_SCATTERING_TRANSFORM (pbb) -= nb_dims_to_remove;
-      free (ds);
-    }
-
-  mpz_clear (x);
-  ppl_delete_Coefficient (one);
-}
-
-/* Flattens all the loop nests of LST.  Return true when something
-   changed.  */
-
-static bool
-lst_do_flatten (lst_p lst)
-{
-  int i;
-  lst_p l;
-  bool res = false;
-  mpz_t zero;
-
-  if (!lst
-      || !LST_LOOP_P (lst))
-    return false;
-
-  mpz_init (zero);
-  mpz_set_si (zero, 0);
-
-  FOR_EACH_VEC_ELT (lst_p, LST_SEQ (lst), i, l)
-    if (LST_LOOP_P (l))
-      {
-	res |= lst_flatten_loop (l, zero);
-	remove_unused_scattering_dimensions (l);
-      }
-
-  lst_update_scattering (lst);
-  mpz_clear (zero);
-  return res;
-}
 
 /* Flatten all the loop nests in SCOP.  Returns true when something
    changed.  */
 
 bool
-flatten_all_loops (scop_p scop)
+flatten_all_loops (scop_p scop ATTRIBUTE_UNUSED)
 {
-  return lst_do_flatten (SCOP_TRANSFORMED_SCHEDULE (scop));
+  /* FIXME: This pass is disabled until it is translated to use
+     isl_map_flatten_range.  */
+  return false;
 }
 
 #endif
-- 
1.7.4.1