CbC/CbC_gcc: gcc/graphite.c comparison

comparison gcc/graphite.c @ 0:a06113de4d67

first commit

author	kent <kent@cr.ie.u-ryukyu.ac.jp>
date	Fri, 17 Jul 2009 14:47:48 +0900
parents
children	77e2b8dfacca

comparison

equal deleted inserted replaced

--1:000000000000
+:a06113de4d67
+/* Gimple Represented as Polyhedra.
+Copyright (C) 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
+Contributed by Sebastian Pop <sebastian.pop@inria.fr>.
+This file is part of GCC.
+GCC 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, or (at your option)
+any later version.
+GCC 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 GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+/* This pass converts GIMPLE to GRAPHITE, performs some loop
+transformations and then converts the resulting representation back
+to GIMPLE.
+An early description of this pass can be found in the GCC Summit'06
+paper "GRAPHITE: Polyhedral Analyses and Optimizations for GCC".
+The wiki page http://gcc.gnu.org/wiki/Graphite contains pointers to
+the related work.
+One important document to read is CLooG's internal manual:
+http://repo.or.cz/w/cloog-ppl.git?a=blob_plain;f=doc/cloog.texi;hb=HEAD
+that describes the data structure of loops used in this file, and
+the functions that are used for transforming the code.  */
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tm.h"
+#include "ggc.h"
+#include "tree.h"
+#include "rtl.h"
+#include "basic-block.h"
+#include "diagnostic.h"
+#include "tree-flow.h"
+#include "toplev.h"
+#include "tree-dump.h"
+#include "timevar.h"
+#include "cfgloop.h"
+#include "tree-chrec.h"
+#include "tree-data-ref.h"
+#include "tree-scalar-evolution.h"
+#include "tree-pass.h"
+#include "domwalk.h"
+#include "value-prof.h"
+#include "pointer-set.h"
+#include "gimple.h"
+#ifdef HAVE_cloog
+#include "cloog/cloog.h"
+#include "graphite.h"
+static VEC (scop_p, heap) *current_scops;
+/* Converts a GMP constant V to a tree and returns it.  */
+static tree
+gmp_cst_to_tree (tree type, Value v)
+{
+return build_int_cst (type, value_get_si (v));
+}
+/* Returns true when BB is in REGION.  */
+static bool
+bb_in_sese_p (basic_block bb, sese region)
+{
+return pointer_set_contains (SESE_REGION_BBS (region), bb);
+}
+/* Returns true when LOOP is in the SESE region R.  */
+static inline bool
+loop_in_sese_p (struct loop *loop, sese r)
+{
+return (bb_in_sese_p (loop->header, r)
+	  && bb_in_sese_p (loop->latch, r));
+}
+/* For a USE in BB, if BB is outside REGION, mark the USE in the
+SESE_LIVEIN and SESE_LIVEOUT sets.  */
+static void
+sese_build_livein_liveouts_use (sese region, basic_block bb, tree use)
+{
+unsigned ver;
+basic_block def_bb;
+if (TREE_CODE (use) != SSA_NAME)
+return;
+ver = SSA_NAME_VERSION (use);
+def_bb = gimple_bb (SSA_NAME_DEF_STMT (use));
+if (!def_bb
+|| !bb_in_sese_p (def_bb, region)
+|| bb_in_sese_p (bb, region))
+return;
+if (!SESE_LIVEIN_VER (region, ver))
+SESE_LIVEIN_VER (region, ver) = BITMAP_ALLOC (NULL);
+bitmap_set_bit (SESE_LIVEIN_VER (region, ver), bb->index);
+bitmap_set_bit (SESE_LIVEOUT (region), ver);
+}
+/* Marks for rewrite all the SSA_NAMES defined in REGION and that are
+used in BB that is outside of the REGION.  */
+static void
+sese_build_livein_liveouts_bb (sese region, basic_block bb)
+{
+gimple_stmt_iterator bsi;
+edge e;
+edge_iterator ei;
+ssa_op_iter iter;
+tree var;
+FOR_EACH_EDGE (e, ei, bb->succs)
+for (bsi = gsi_start_phis (e->dest); !gsi_end_p (bsi); gsi_next (&bsi))
+sese_build_livein_liveouts_use (region, bb,
+				      PHI_ARG_DEF_FROM_EDGE (gsi_stmt (bsi), e));
+for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi))
+FOR_EACH_SSA_TREE_OPERAND (var, gsi_stmt (bsi), iter, SSA_OP_ALL_USES)
+sese_build_livein_liveouts_use (region, bb, var);
+}
+/* Build the SESE_LIVEIN and SESE_LIVEOUT for REGION.  */
+void
+sese_build_livein_liveouts (sese region)
+{
+basic_block bb;
+SESE_LIVEOUT (region) = BITMAP_ALLOC (NULL);
+SESE_NUM_VER (region) = num_ssa_names;
+SESE_LIVEIN (region) = XCNEWVEC (bitmap, SESE_NUM_VER (region));
+FOR_EACH_BB (bb)
+sese_build_livein_liveouts_bb (region, bb);
+}
+/* Register basic blocks belonging to a region in a pointer set.  */
+static void
+register_bb_in_sese (basic_block entry_bb, basic_block exit_bb, sese region)
+{
+edge_iterator ei;
+edge e;
+basic_block bb = entry_bb;
+FOR_EACH_EDGE (e, ei, bb->succs)
+{
+if (!pointer_set_contains (SESE_REGION_BBS (region), e->dest) &&
+	  e->dest->index != exit_bb->index)
+	{
+	  pointer_set_insert (SESE_REGION_BBS (region), e->dest);
+	  register_bb_in_sese (e->dest, exit_bb, region);
+	}
+}
+}
+/* Builds a new SESE region from edges ENTRY and EXIT.  */
+sese
+new_sese (edge entry, edge exit)
+{
+sese res = XNEW (struct sese);
+SESE_ENTRY (res) = entry;
+SESE_EXIT (res) = exit;
+SESE_REGION_BBS (res) = pointer_set_create ();
+register_bb_in_sese (entry->dest, exit->dest, res);
+SESE_LIVEOUT (res) = NULL;
+SESE_NUM_VER (res) = 0;
+SESE_LIVEIN (res) = NULL;
+return res;
+}
+/* Deletes REGION.  */
+void
+free_sese (sese region)
+{
+int i;
+for (i = 0; i < SESE_NUM_VER (region); i++)
+BITMAP_FREE (SESE_LIVEIN_VER (region, i));
+if (SESE_LIVEIN (region))
+free (SESE_LIVEIN (region));
+if (SESE_LIVEOUT (region))
+BITMAP_FREE (SESE_LIVEOUT (region));
+pointer_set_destroy (SESE_REGION_BBS (region));
+XDELETE (region);
+}
+/* Debug the list of old induction variables for this SCOP.  */
+void
+debug_oldivs (scop_p scop)
+{
+int i;
+name_tree oldiv;
+fprintf (stderr, "Old IVs:");
+for (i = 0; VEC_iterate (name_tree, SCOP_OLDIVS (scop), i, oldiv); i++)
+{
+fprintf (stderr, "(");
+print_generic_expr (stderr, oldiv->t, 0);
+fprintf (stderr, ", %s, %d)\n", oldiv->name, oldiv->loop->num);
+}
+fprintf (stderr, "\n");
+}
+/* Debug the loops around basic block GB.  */
+void
+debug_loop_vec (graphite_bb_p gb)
+{
+int i;
+loop_p loop;
+fprintf (stderr, "Loop Vec:");
+for (i = 0; VEC_iterate (loop_p, GBB_LOOPS (gb), i, loop); i++)
+fprintf (stderr, "%d: %d, ", i, loop ? loop->num : -1);
+fprintf (stderr, "\n");
+}
+/* Returns true if stack ENTRY is a constant.  */
+static bool
+iv_stack_entry_is_constant (iv_stack_entry *entry)
+{
+return entry->kind == iv_stack_entry_const;
+}
+/* Returns true if stack ENTRY is an induction variable.  */
+static bool
+iv_stack_entry_is_iv (iv_stack_entry *entry)
+{
+return entry->kind == iv_stack_entry_iv;
+}
+/* Push (IV, NAME) on STACK.  */
+static void
+loop_iv_stack_push_iv (loop_iv_stack stack, tree iv, const char *name)
+{
+iv_stack_entry *entry = XNEW (iv_stack_entry);
+name_tree named_iv = XNEW (struct name_tree);
+named_iv->t = iv;
+named_iv->name = name;
+entry->kind = iv_stack_entry_iv;
+entry->data.iv = named_iv;
+VEC_safe_push (iv_stack_entry_p, heap, *stack, entry);
+}
+/* Inserts a CONSTANT in STACK at INDEX.  */
+static void
+loop_iv_stack_insert_constant (loop_iv_stack stack, int index,
+			       tree constant)
+{
+iv_stack_entry *entry = XNEW (iv_stack_entry);
+entry->kind = iv_stack_entry_const;
+entry->data.constant = constant;
+VEC_safe_insert (iv_stack_entry_p, heap, *stack, index, entry);
+}
+/* Pops and frees an element out of STACK.  */
+static void
+loop_iv_stack_pop (loop_iv_stack stack)
+{
+iv_stack_entry_p entry = VEC_pop (iv_stack_entry_p, *stack);
+free (entry->data.iv);
+free (entry);
+}
+/* Get the IV at INDEX in STACK.  */
+static tree
+loop_iv_stack_get_iv (loop_iv_stack stack, int index)
+{
+iv_stack_entry_p entry = VEC_index (iv_stack_entry_p, *stack, index);
+iv_stack_entry_data data = entry->data;
+return iv_stack_entry_is_iv (entry) ? data.iv->t : data.constant;
+}
+/* Get the IV from its NAME in STACK.  */
+static tree
+loop_iv_stack_get_iv_from_name (loop_iv_stack stack, const char* name)
+{
+int i;
+iv_stack_entry_p entry;
+for (i = 0; VEC_iterate (iv_stack_entry_p, *stack, i, entry); i++)
+{
+name_tree iv = entry->data.iv;
+if (!strcmp (name, iv->name))
+	return iv->t;
+}
+return NULL;
+}
+/* Prints on stderr the contents of STACK.  */
+void
+debug_loop_iv_stack (loop_iv_stack stack)
+{
+int i;
+iv_stack_entry_p entry;
+bool first = true;
+fprintf (stderr, "(");
+for (i = 0; VEC_iterate (iv_stack_entry_p, *stack, i, entry); i++)
+{
+if (first)
+	first = false;
+else
+	fprintf (stderr, " ");
+if (iv_stack_entry_is_iv (entry))
+	{
+	  name_tree iv = entry->data.iv;
+	  fprintf (stderr, "%s:", iv->name);
+	  print_generic_expr (stderr, iv->t, 0);
+	}
+else
+	{
+	  tree constant = entry->data.constant;
+	  print_generic_expr (stderr, constant, 0);
+	  fprintf (stderr, ":");
+	  print_generic_expr (stderr, constant, 0);
+	}
+}
+fprintf (stderr, ")\n");
+}
+/* Frees STACK.  */
+static void
+free_loop_iv_stack (loop_iv_stack stack)
+{
+int i;
+iv_stack_entry_p entry;
+for (i = 0; VEC_iterate (iv_stack_entry_p, *stack, i, entry); i++)
+{
+free (entry->data.iv);
+free (entry);
+}
+VEC_free (iv_stack_entry_p, heap, *stack);
+}
+/* Structure containing the mapping between the CLooG's induction
+variable and the type of the old induction variable.  */
+typedef struct ivtype_map_elt
+{
+tree type;
+const char *cloog_iv;
+} *ivtype_map_elt;
+/* Print to stderr the element ELT.  */
+static void
+debug_ivtype_elt (ivtype_map_elt elt)
+{
+fprintf (stderr, "(%s, ", elt->cloog_iv);
+print_generic_expr (stderr, elt->type, 0);
+fprintf (stderr, ")\n");
+}
+/* Helper function for debug_ivtype_map.  */
+static int
+debug_ivtype_map_1 (void **slot, void *s ATTRIBUTE_UNUSED)
+{
+struct ivtype_map_elt *entry = (struct ivtype_map_elt *) *slot;
+debug_ivtype_elt (entry);
+return 1;
+}
+/* Print to stderr all the elements of MAP.  */
+void
+debug_ivtype_map (htab_t map)
+{
+htab_traverse (map, debug_ivtype_map_1, NULL);
+}
+/* Constructs a new SCEV_INFO_STR structure for VAR and INSTANTIATED_BELOW.  */
+static inline ivtype_map_elt
+new_ivtype_map_elt (const char *cloog_iv, tree type)
+{
+ivtype_map_elt res;
+res = XNEW (struct ivtype_map_elt);
+res->cloog_iv = cloog_iv;
+res->type = type;
+return res;
+}
+/* Computes a hash function for database element ELT.  */
+static hashval_t
+ivtype_map_elt_info (const void *elt)
+{
+return htab_hash_pointer (((const struct ivtype_map_elt *) elt)->cloog_iv);
+}
+/* Compares database elements E1 and E2.  */
+static int
+eq_ivtype_map_elts (const void *e1, const void *e2)
+{
+const struct ivtype_map_elt *elt1 = (const struct ivtype_map_elt *) e1;
+const struct ivtype_map_elt *elt2 = (const struct ivtype_map_elt *) e2;
+return (elt1->cloog_iv == elt2->cloog_iv);
+}
+/* Given a CLOOG_IV, returns the type that it should have in GCC land.
+If the information is not available, i.e. in the case one of the
+transforms created the loop, just return integer_type_node.  */
+static tree
+gcc_type_for_cloog_iv (const char *cloog_iv, graphite_bb_p gbb)
+{
+struct ivtype_map_elt tmp;
+PTR *slot;
+tmp.cloog_iv = cloog_iv;
+slot = htab_find_slot (GBB_CLOOG_IV_TYPES (gbb), &tmp, NO_INSERT);
+if (slot && *slot)
+return ((ivtype_map_elt) *slot)->type;
+return integer_type_node;
+}
+/* Inserts constants derived from the USER_STMT argument list into the
+STACK.  This is needed to map old ivs to constants when loops have
+been eliminated.  */
+static void
+loop_iv_stack_patch_for_consts (loop_iv_stack stack,
+				struct clast_user_stmt *user_stmt)
+{
+struct clast_stmt *t;
+int index = 0;
+CloogStatement *cs = user_stmt->statement;
+graphite_bb_p gbb = (graphite_bb_p) cloog_statement_usr (cs);
+for (t = user_stmt->substitutions; t; t = t->next)
+{
+struct clast_expr *expr = (struct clast_expr *)
+	((struct clast_assignment *)t)->RHS;
+struct clast_term *term = (struct clast_term *) expr;
+/* FIXME: What should be done with expr_bin, expr_red?  */
+if (expr->type == expr_term
+	  && !term->var)
+	{
+	  loop_p loop = gbb_loop_at_index (gbb, index);
+	  tree oldiv = oldiv_for_loop (GBB_SCOP (gbb), loop);
+	  tree type = oldiv ? TREE_TYPE (oldiv) : integer_type_node;
+	  tree value = gmp_cst_to_tree (type, term->val);
+	  loop_iv_stack_insert_constant (stack, index, value);
+	}
+index = index + 1;
+}
+}
+/* Removes all constants in the iv STACK.  */
+static void
+loop_iv_stack_remove_constants (loop_iv_stack stack)
+{
+int i;
+iv_stack_entry *entry;
+for (i = 0; VEC_iterate (iv_stack_entry_p, *stack, i, entry);)
+{
+if (iv_stack_entry_is_constant (entry))
+	{
+	  free (VEC_index (iv_stack_entry_p, *stack, i));
+	  VEC_ordered_remove (iv_stack_entry_p, *stack, i);
+	}
+else
+	i++;
+}
+}
+/* Returns a new loop_to_cloog_loop_str structure.  */
+static inline struct loop_to_cloog_loop_str *
+new_loop_to_cloog_loop_str (int loop_num,
+int loop_position,
+CloogLoop *cloog_loop)
+{
+struct loop_to_cloog_loop_str *result;
+result = XNEW (struct loop_to_cloog_loop_str);
+result->loop_num = loop_num;
+result->cloog_loop = cloog_loop;
+result->loop_position = loop_position;
+return result;
+}
+/* Hash function for SCOP_LOOP2CLOOG_LOOP hash table.  */
+static hashval_t
+hash_loop_to_cloog_loop (const void *elt)
+{
+return ((const struct loop_to_cloog_loop_str *) elt)->loop_num;
+}
+/* Equality function for SCOP_LOOP2CLOOG_LOOP hash table.  */
+static int
+eq_loop_to_cloog_loop (const void *el1, const void *el2)
+{
+const struct loop_to_cloog_loop_str *elt1, *elt2;
+elt1 = (const struct loop_to_cloog_loop_str *) el1;
+elt2 = (const struct loop_to_cloog_loop_str *) el2;
+return elt1->loop_num == elt2->loop_num;
+}
+/* Compares two graphite bbs and returns an integer less than, equal to, or
+greater than zero if the first argument is considered to be respectively
+less than, equal to, or greater than the second.
+We compare using the lexicographic order of the static schedules.  */
+static int
+gbb_compare (const void *p_1, const void *p_2)
+{
+const struct graphite_bb *const gbb_1
+= *(const struct graphite_bb *const*) p_1;
+const struct graphite_bb *const gbb_2
+= *(const struct graphite_bb *const*) p_2;
+return lambda_vector_compare (GBB_STATIC_SCHEDULE (gbb_1),
+gbb_nb_loops (gbb_1) + 1,
+GBB_STATIC_SCHEDULE (gbb_2),
+gbb_nb_loops (gbb_2) + 1);
+}
+/* Sort graphite bbs in SCOP.  */
+static void
+graphite_sort_gbbs (scop_p scop)
+{
+VEC (graphite_bb_p, heap) *bbs = SCOP_BBS (scop);
+qsort (VEC_address (graphite_bb_p, bbs),
+VEC_length (graphite_bb_p, bbs),
+sizeof (graphite_bb_p), gbb_compare);
+}
+/* Dump conditions of a graphite basic block GBB on FILE.  */
+static void
+dump_gbb_conditions (FILE *file, graphite_bb_p gbb)
+{
+int i;
+gimple stmt;
+VEC (gimple, heap) *conditions = GBB_CONDITIONS (gbb);
+if (VEC_empty (gimple, conditions))
+return;
+fprintf (file, "\tbb %d\t: cond = {", GBB_BB (gbb)->index);
+for (i = 0; VEC_iterate (gimple, conditions, i, stmt); i++)
+print_gimple_stmt (file, stmt, 0, 0);
+fprintf (file, "}\n");
+}
+/* Converts the graphite scheduling function into a cloog scattering
+matrix.  This scattering matrix is used to limit the possible cloog
+output to valid programs in respect to the scheduling function.
+SCATTERING_DIMENSIONS specifies the dimensionality of the scattering
+matrix. CLooG 0.14.0 and previous versions require, that all scattering
+functions of one CloogProgram have the same dimensionality, therefore we
+allow to specify it. (Should be removed in future versions)  */
+static CloogMatrix *
+schedule_to_scattering (graphite_bb_p gb, int scattering_dimensions)
+{
+int i;
+scop_p scop = GBB_SCOP (gb);
+int nb_iterators = gbb_nb_loops (gb);
+/* The cloog scattering matrix consists of these colums:
+1                        col  = Eq/Inq,
+scattering_dimensions    cols = Scattering dimensions,
+nb_iterators             cols = bb's iterators,
+scop_nb_params        cols = Parameters,
+1                        col  = Constant 1.
+Example:
+scattering_dimensions = 5
+max_nb_iterators = 2
+nb_iterators = 1
+scop_nb_params = 2
+Schedule:
+? i
+4 5
+Scattering Matrix:
+s1  s2  s3  s4  s5  i   p1  p2  1
+1   0   0   0   0   0   0   0  -4  = 0
+0   1   0   0   0  -1   0   0   0  = 0
+0   0   1   0   0   0   0   0  -5  = 0  */
+int nb_params = scop_nb_params (scop);
+int nb_cols = 1 + scattering_dimensions + nb_iterators + nb_params + 1;
+int col_const = nb_cols - 1;
+int col_iter_offset = 1 + scattering_dimensions;
+CloogMatrix *scat = cloog_matrix_alloc (scattering_dimensions, nb_cols);
+gcc_assert (scattering_dimensions >= nb_iterators * 2 + 1);
+/* Initialize the identity matrix.  */
+for (i = 0; i < scattering_dimensions; i++)
+value_set_si (scat->p[i][i + 1], 1);
+/* Textual order outside the first loop */
+value_set_si (scat->p[0][col_const], -GBB_STATIC_SCHEDULE (gb)[0]);
+/* For all surrounding loops.  */
+for (i = 0;  i < nb_iterators; i++)
+{
+int schedule = GBB_STATIC_SCHEDULE (gb)[i + 1];
+/* Iterations of this loop.  */
+value_set_si (scat->p[2 * i + 1][col_iter_offset + i], -1);
+/* Textual order inside this loop.  */
+value_set_si (scat->p[2 * i + 2][col_const], -schedule);
+}
+return scat;
+}
+/* Print the schedules of GB to FILE with INDENT white spaces before.
+VERBOSITY determines how verbose the code pretty printers are.  */
+void
+print_graphite_bb (FILE *file, graphite_bb_p gb, int indent, int verbosity)
+{
+CloogMatrix *scattering;
+int i;
+loop_p loop;
+fprintf (file, "\nGBB (\n");
+print_loops_bb (file, GBB_BB (gb), indent+2, verbosity);
+if (GBB_DOMAIN (gb))
+{
+fprintf (file, "       (domain: \n");
+cloog_matrix_print (file, GBB_DOMAIN (gb));
+fprintf (file, "       )\n");
+}
+if (GBB_STATIC_SCHEDULE (gb))
+{
+fprintf (file, "       (static schedule: ");
+print_lambda_vector (file, GBB_STATIC_SCHEDULE (gb),
+			   gbb_nb_loops (gb) + 1);
+fprintf (file, "       )\n");
+}
+if (GBB_LOOPS (gb))
+{
+fprintf (file, "       (contained loops: \n");
+for (i = 0; VEC_iterate (loop_p, GBB_LOOPS (gb), i, loop); i++)
+	if (loop == NULL)
+	  fprintf (file, "       iterator %d   =>  NULL \n", i);
+	else
+	  fprintf (file, "       iterator %d   =>  loop %d \n", i,
+		   loop->num);
+fprintf (file, "       )\n");
+}
+if (GBB_DATA_REFS (gb))
+dump_data_references (file, GBB_DATA_REFS (gb));
+if (GBB_CONDITIONS (gb))
+{
+fprintf (file, "       (conditions: \n");
+dump_gbb_conditions (file, gb);
+fprintf (file, "       )\n");
+}
+if (GBB_SCOP (gb)
+&& GBB_STATIC_SCHEDULE (gb))
+{
+fprintf (file, "       (scattering: \n");
+scattering = schedule_to_scattering (gb, 2 * gbb_nb_loops (gb) + 1);
+cloog_matrix_print (file, scattering);
+cloog_matrix_free (scattering);
+fprintf (file, "       )\n");
+}
+fprintf (file, ")\n");
+}
+/* Print to STDERR the schedules of GB with VERBOSITY level.  */
+void
+debug_gbb (graphite_bb_p gb, int verbosity)
+{
+print_graphite_bb (stderr, gb, 0, verbosity);
+}
+/* Print SCOP to FILE.  VERBOSITY determines how verbose the pretty
+printers are.  */
+static void
+print_scop (FILE *file, scop_p scop, int verbosity)
+{
+if (scop == NULL)
+return;
+fprintf (file, "\nSCoP_%d_%d (\n",
+	   SCOP_ENTRY (scop)->index, SCOP_EXIT (scop)->index);
+fprintf (file, "       (cloog: \n");
+cloog_program_print (file, SCOP_PROG (scop));
+fprintf (file, "       )\n");
+if (SCOP_BBS (scop))
+{
+graphite_bb_p gb;
+int i;
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gb); i++)
+	print_graphite_bb (file, gb, 0, verbosity);
+}
+fprintf (file, ")\n");
+}
+/* Print all the SCOPs to FILE.  VERBOSITY determines how verbose the
+code pretty printers are.  */
+static void
+print_scops (FILE *file, int verbosity)
+{
+int i;
+scop_p scop;
+for (i = 0; VEC_iterate (scop_p, current_scops, i, scop); i++)
+print_scop (file, scop, verbosity);
+}
+/* Debug SCOP.  VERBOSITY determines how verbose the code pretty
+printers are. */
+void
+debug_scop (scop_p scop, int verbosity)
+{
+print_scop (stderr, scop, verbosity);
+}
+/* Debug all SCOPs from CURRENT_SCOPS.  VERBOSITY determines how
+verbose the code pretty printers are.  */
+void
+debug_scops (int verbosity)
+{
+print_scops (stderr, verbosity);
+}
+/* Pretty print to FILE the SCOP in DOT format.  */
+static void
+dot_scop_1 (FILE *file, scop_p scop)
+{
+edge e;
+edge_iterator ei;
+basic_block bb;
+basic_block entry = SCOP_ENTRY (scop);
+basic_block exit = SCOP_EXIT (scop);
+fprintf (file, "digraph SCoP_%d_%d {\n", entry->index,
+	   exit->index);
+FOR_ALL_BB (bb)
+{
+if (bb == entry)
+	fprintf (file, "%d [shape=triangle];\n", bb->index);
+if (bb == exit)
+	fprintf (file, "%d [shape=box];\n", bb->index);
+if (bb_in_sese_p (bb, SCOP_REGION (scop)))
+	fprintf (file, "%d [color=red];\n", bb->index);
+FOR_EACH_EDGE (e, ei, bb->succs)
+	fprintf (file, "%d -> %d;\n", bb->index, e->dest->index);
+}
+fputs ("}\n\n", file);
+}
+/* Display SCOP using dotty.  */
+void
+dot_scop (scop_p scop)
+{
+dot_scop_1 (stderr, scop);
+}
+/* Pretty print all SCoPs in DOT format and mark them with different colors.
+If there are not enough colors, paint later SCoPs gray.
+Special nodes:
+- "*" after the node number: entry of a SCoP,
+- "#" after the node number: exit of a SCoP,
+- "()" entry or exit not part of SCoP.  */
+static void
+dot_all_scops_1 (FILE *file)
+{
+basic_block bb;
+edge e;
+edge_iterator ei;
+scop_p scop;
+const char* color;
+int i;
+/* Disable debugging while printing graph.  */
+int tmp_dump_flags = dump_flags;
+dump_flags = 0;
+fprintf (file, "digraph all {\n");
+FOR_ALL_BB (bb)
+{
+int part_of_scop = false;
+/* Use HTML for every bb label.  So we are able to print bbs
+which are part of two different SCoPs, with two different
+background colors.  */
+fprintf (file, "%d [label=<\n  <TABLE BORDER=\"0\" CELLBORDER=\"1\" ",
+bb->index);
+fprintf (file, "CELLSPACING=\"0\">\n");
+/* Select color for SCoP.  */
+for (i = 0; VEC_iterate (scop_p, current_scops, i, scop); i++)
+	if (bb_in_sese_p (bb, SCOP_REGION (scop))
+	    || (SCOP_EXIT (scop) == bb)
+	    || (SCOP_ENTRY (scop) == bb))
+	  {
+	    switch (i % 17)
+	      {
+	      case 0: /* red */
+		color = "#e41a1c";
+		break;
+	      case 1: /* blue */
+		color = "#377eb8";
+		break;
+	      case 2: /* green */
+		color = "#4daf4a";
+		break;
+	      case 3: /* purple */
+		color = "#984ea3";
+		break;
+	      case 4: /* orange */
+		color = "#ff7f00";
+		break;
+	      case 5: /* yellow */
+		color = "#ffff33";
+		break;
+	      case 6: /* brown */
+		color = "#a65628";
+		break;
+	      case 7: /* rose */
+		color = "#f781bf";
+		break;
+	      case 8:
+		color = "#8dd3c7";
+		break;
+	      case 9:
+		color = "#ffffb3";
+		break;
+	      case 10:
+		color = "#bebada";
+		break;
+	      case 11:
+		color = "#fb8072";
+		break;
+	      case 12:
+		color = "#80b1d3";
+		break;
+	      case 13:
+		color = "#fdb462";
+		break;
+	      case 14:
+		color = "#b3de69";
+		break;
+	      case 15:
+		color = "#fccde5";
+		break;
+	      case 16:
+		color = "#bc80bd";
+		break;
+	      default: /* gray */
+		color = "#999999";
+	      }
+	    fprintf (file, "    <TR><TD WIDTH=\"50\" BGCOLOR=\"%s\">", color);
+	    if (!bb_in_sese_p (bb, SCOP_REGION (scop)))
+	      fprintf (file, " (");
+	    if (bb == SCOP_ENTRY (scop)
+		&& bb == SCOP_EXIT (scop))
+	      fprintf (file, " %d*# ", bb->index);
+	    else if (bb == SCOP_ENTRY (scop))
+	      fprintf (file, " %d* ", bb->index);
+	    else if (bb == SCOP_EXIT (scop))
+	      fprintf (file, " %d# ", bb->index);
+	    else
+	      fprintf (file, " %d ", bb->index);
+	    if (!bb_in_sese_p (bb, SCOP_REGION (scop)))
+	      fprintf (file, ")");
+	    fprintf (file, "</TD></TR>\n");
+	    part_of_scop  = true;
+	  }
+if (!part_of_scop)
+{
+fprintf (file, "    <TR><TD WIDTH=\"50\" BGCOLOR=\"#ffffff\">");
+fprintf (file, " %d </TD></TR>\n", bb->index);
+}
+fprintf (file, "  </TABLE>>, shape=box, style=\"setlinewidth(0)\"]\n");
+}
+FOR_ALL_BB (bb)
+{
+FOR_EACH_EDGE (e, ei, bb->succs)
+	      fprintf (file, "%d -> %d;\n", bb->index, e->dest->index);
+}
+fputs ("}\n\n", file);
+/* Enable debugging again.  */
+dump_flags = tmp_dump_flags;
+}
+/* Display all SCoPs using dotty.  */
+void
+dot_all_scops (void)
+{
+/* When debugging, enable the following code.  This cannot be used
+in production compilers because it calls "system".  */
+#if 0
+FILE *stream = fopen ("/tmp/allscops.dot", "w");
+gcc_assert (stream);
+dot_all_scops_1 (stream);
+fclose (stream);
+system ("dotty /tmp/allscops.dot");
+#else
+dot_all_scops_1 (stderr);
+#endif
+}
+/* Returns the outermost loop in SCOP that contains BB.  */
+static struct loop *
+outermost_loop_in_scop (scop_p scop, basic_block bb)
+{
+struct loop *nest;
+nest = bb->loop_father;
+while (loop_outer (nest)
+	 && loop_in_sese_p (loop_outer (nest), SCOP_REGION (scop)))
+nest = loop_outer (nest);
+return nest;
+}
+/* Returns the block preceding the entry of SCOP.  */
+static basic_block
+block_before_scop (scop_p scop)
+{
+return SESE_ENTRY (SCOP_REGION (scop))->src;
+}
+/* Return true when EXPR is an affine function in LOOP with parameters
+instantiated relative to SCOP_ENTRY.  */
+static bool
+loop_affine_expr (basic_block scop_entry, struct loop *loop, tree expr)
+{
+int n = loop->num;
+tree scev = analyze_scalar_evolution (loop, expr);
+scev = instantiate_scev (scop_entry, loop, scev);
+return (evolution_function_is_invariant_p (scev, n)
+	  || evolution_function_is_affine_multivariate_p (scev, n));
+}
+/* Return true if REF or any of its subtrees contains a
+component_ref.  */
+static bool
+contains_component_ref_p (tree ref)
+{
+if (!ref)
+return false;
+while (handled_component_p (ref))
+{
+if (TREE_CODE (ref) == COMPONENT_REF)
+	return true;
+ref = TREE_OPERAND (ref, 0);
+}
+return false;
+}
+/* Return true if the operand OP is simple.  */
+static bool
+is_simple_operand (loop_p loop, gimple stmt, tree op)
+{
+/* It is not a simple operand when it is a declaration,  */
+if (DECL_P (op)
+/* or a structure,  */
+|| AGGREGATE_TYPE_P (TREE_TYPE (op))
+/* or a COMPONENT_REF,  */
+|| contains_component_ref_p (op)
+/* or a memory access that cannot be analyzed by the data
+	 reference analysis.  */
+|| ((handled_component_p (op) || INDIRECT_REF_P (op))
+	  && !stmt_simple_memref_p (loop, stmt, op)))
+return false;
+return true;
+}
+/* Return true only when STMT is simple enough for being handled by
+Graphite.  This depends on SCOP_ENTRY, as the parametetrs are
+initialized relatively to this basic block.  */
+static bool
+stmt_simple_for_scop_p (basic_block scop_entry, gimple stmt)
+{
+basic_block bb = gimple_bb (stmt);
+struct loop *loop = bb->loop_father;
+/* GIMPLE_ASM and GIMPLE_CALL may embed arbitrary side effects.
+Calls have side-effects, except those to const or pure
+functions.  */
+if (gimple_has_volatile_ops (stmt)
+|| (gimple_code (stmt) == GIMPLE_CALL
+	  && !(gimple_call_flags (stmt) & (ECF_CONST | ECF_PURE)))
+|| (gimple_code (stmt) == GIMPLE_ASM))
+return false;
+switch (gimple_code (stmt))
+{
+case GIMPLE_RETURN:
+case GIMPLE_LABEL:
+return true;
+case GIMPLE_COND:
+{
+	tree op;
+	ssa_op_iter op_iter;
+enum tree_code code = gimple_cond_code (stmt);
+/* We can only handle this kind of conditional expressions.
+For inequalities like "if (i != 3 * k)" we need unions of
+polyhedrons.  Expressions like  "if (a)" or "if (a == 15)" need
+them for the else branch.  */
+if (!(code == LT_EXPR
+	      || code == GT_EXPR
+|| code == LE_EXPR
+	      || code == GE_EXPR))
+return false;
+	if (!scop_entry)
+	  return false;
+	FOR_EACH_SSA_TREE_OPERAND (op, stmt, op_iter, SSA_OP_ALL_USES)
+	  if (!loop_affine_expr (scop_entry, loop, op))
+	    return false;
+	return true;
+}
+case GIMPLE_ASSIGN:
+{
+	enum tree_code code = gimple_assign_rhs_code (stmt);
+	switch (get_gimple_rhs_class (code))
+	  {
+	  case GIMPLE_UNARY_RHS:
+	  case GIMPLE_SINGLE_RHS:
+	    return (is_simple_operand (loop, stmt, gimple_assign_lhs (stmt))
+		    && is_simple_operand (loop, stmt, gimple_assign_rhs1 (stmt)));
+	  case GIMPLE_BINARY_RHS:
+	    return (is_simple_operand (loop, stmt, gimple_assign_lhs (stmt))
+		    && is_simple_operand (loop, stmt, gimple_assign_rhs1 (stmt))
+		    && is_simple_operand (loop, stmt, gimple_assign_rhs2 (stmt)));
+	  case GIMPLE_INVALID_RHS:
+	  default:
+	    gcc_unreachable ();
+	  }
+}
+case GIMPLE_CALL:
+{
+	size_t i;
+	size_t n = gimple_call_num_args (stmt);
+	tree lhs = gimple_call_lhs (stmt);
+	if (lhs && !is_simple_operand (loop, stmt, lhs))
+	  return false;
+	for (i = 0; i < n; i++)
+	  if (!is_simple_operand (loop, stmt, gimple_call_arg (stmt, i)))
+	    return false;
+	return true;
+}
+default:
+/* These nodes cut a new scope.  */
+return false;
+}
+return false;
+}
+/* Returns the statement of BB that contains a harmful operation: that
+can be a function call with side effects, the induction variables
+are not linear with respect to SCOP_ENTRY, etc.  The current open
+scop should end before this statement.  */
+static gimple
+harmful_stmt_in_bb (basic_block scop_entry, basic_block bb)
+{
+gimple_stmt_iterator gsi;
+gimple stmt;
+for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+if (!stmt_simple_for_scop_p (scop_entry, gsi_stmt (gsi)))
+return gsi_stmt (gsi);
+stmt = last_stmt (bb);
+if (stmt && gimple_code (stmt) == GIMPLE_COND)
+{
+tree lhs = gimple_cond_lhs (stmt);
+tree rhs = gimple_cond_rhs (stmt);
+if (TREE_CODE (TREE_TYPE (lhs)) == REAL_TYPE
+	  || TREE_CODE (TREE_TYPE (rhs)) == REAL_TYPE)
+	return stmt;
+}
+return NULL;
+}
+/* Returns true when BB will be represented in graphite.  Return false
+for the basic blocks that contain code eliminated in the code
+generation pass: i.e. induction variables and exit conditions.  */
+static bool
+graphite_stmt_p (scop_p scop, basic_block bb,
+		 VEC (data_reference_p, heap) *drs)
+{
+gimple_stmt_iterator gsi;
+loop_p loop = bb->loop_father;
+if (VEC_length (data_reference_p, drs) > 0)
+return true;
+for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+{
+gimple stmt = gsi_stmt (gsi);
+switch (gimple_code (stmt))
+{
+/* Control flow expressions can be ignored, as they are
+represented in the iteration domains and will be
+regenerated by graphite.  */
+	case GIMPLE_COND:
+	case GIMPLE_GOTO:
+	case GIMPLE_SWITCH:
+	  break;
+	case GIMPLE_ASSIGN:
+	  {
+	    tree var = gimple_assign_lhs (stmt);
+	    var = analyze_scalar_evolution (loop, var);
+	    var = instantiate_scev (block_before_scop (scop), loop, var);
+	    if (chrec_contains_undetermined (var))
+	      return true;
+	    break;
+	  }
+	default:
+	  return true;
+}
+}
+return false;
+}
+/* Store the GRAPHITE representation of BB.  */
+static void
+new_graphite_bb (scop_p scop, basic_block bb)
+{
+struct graphite_bb *gbb;
+VEC (data_reference_p, heap) *drs = VEC_alloc (data_reference_p, heap, 5);
+struct loop *nest = outermost_loop_in_scop (scop, bb);
+gimple_stmt_iterator gsi;
+for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+find_data_references_in_stmt (nest, gsi_stmt (gsi), &drs);
+if (!graphite_stmt_p (scop, bb, drs))
+{
+free_data_refs (drs);
+return;
+}
+gbb = XNEW (struct graphite_bb);
+bb->aux = gbb;
+GBB_BB (gbb) = bb;
+GBB_SCOP (gbb) = scop;
+GBB_DATA_REFS (gbb) = drs;
+GBB_DOMAIN (gbb) = NULL;
+GBB_CONDITIONS (gbb) = NULL;
+GBB_CONDITION_CASES (gbb) = NULL;
+GBB_LOOPS (gbb) = NULL;
+GBB_STATIC_SCHEDULE (gbb) = NULL;
+GBB_CLOOG_IV_TYPES (gbb) = NULL;
+VEC_safe_push (graphite_bb_p, heap, SCOP_BBS (scop), gbb);
+}
+/* Frees GBB.  */
+static void
+free_graphite_bb (struct graphite_bb *gbb)
+{
+if (GBB_DOMAIN (gbb))
+cloog_matrix_free (GBB_DOMAIN (gbb));
+if (GBB_CLOOG_IV_TYPES (gbb))
+htab_delete (GBB_CLOOG_IV_TYPES (gbb));
+/* FIXME: free_data_refs is disabled for the moment, but should be
+enabled.
+free_data_refs (GBB_DATA_REFS (gbb)); */
+VEC_free (gimple, heap, GBB_CONDITIONS (gbb));
+VEC_free (gimple, heap, GBB_CONDITION_CASES (gbb));
+VEC_free (loop_p, heap, GBB_LOOPS (gbb));
+GBB_BB (gbb)->aux = 0;
+XDELETE (gbb);
+}
+/* Structure containing the mapping between the old names and the new
+names used after block copy in the new loop context.  */
+typedef struct rename_map_elt
+{
+tree old_name, new_name;
+} *rename_map_elt;
+/* Print to stderr the element ELT.  */
+static void
+debug_rename_elt (rename_map_elt elt)
+{
+fprintf (stderr, "(");
+print_generic_expr (stderr, elt->old_name, 0);
+fprintf (stderr, ", ");
+print_generic_expr (stderr, elt->new_name, 0);
+fprintf (stderr, ")\n");
+}
+/* Helper function for debug_rename_map.  */
+static int
+debug_rename_map_1 (void **slot, void *s ATTRIBUTE_UNUSED)
+{
+struct rename_map_elt *entry = (struct rename_map_elt *) *slot;
+debug_rename_elt (entry);
+return 1;
+}
+/* Print to stderr all the elements of MAP.  */
+void
+debug_rename_map (htab_t map)
+{
+htab_traverse (map, debug_rename_map_1, NULL);
+}
+/* Constructs a new SCEV_INFO_STR structure for VAR and INSTANTIATED_BELOW.  */
+static inline rename_map_elt
+new_rename_map_elt (tree old_name, tree new_name)
+{
+rename_map_elt res;
+res = XNEW (struct rename_map_elt);
+res->old_name = old_name;
+res->new_name = new_name;
+return res;
+}
+/* Computes a hash function for database element ELT.  */
+static hashval_t
+rename_map_elt_info (const void *elt)
+{
+return htab_hash_pointer (((const struct rename_map_elt *) elt)->old_name);
+}
+/* Compares database elements E1 and E2.  */
+static int
+eq_rename_map_elts (const void *e1, const void *e2)
+{
+const struct rename_map_elt *elt1 = (const struct rename_map_elt *) e1;
+const struct rename_map_elt *elt2 = (const struct rename_map_elt *) e2;
+return (elt1->old_name == elt2->old_name);
+}
+/* Returns the new name associated to OLD_NAME in MAP.  */
+static tree
+get_new_name_from_old_name (htab_t map, tree old_name)
+{
+struct rename_map_elt tmp;
+PTR *slot;
+tmp.old_name = old_name;
+slot = htab_find_slot (map, &tmp, NO_INSERT);
+if (slot && *slot)
+return ((rename_map_elt) *slot)->new_name;
+return old_name;
+}
+/* Creates a new scop starting with ENTRY.  */
+static scop_p
+new_scop (edge entry, edge exit)
+{
+scop_p scop = XNEW (struct scop);
+gcc_assert (entry && exit);
+SCOP_REGION (scop) = new_sese (entry, exit);
+SCOP_BBS (scop) = VEC_alloc (graphite_bb_p, heap, 3);
+SCOP_OLDIVS (scop) = VEC_alloc (name_tree, heap, 3);
+SCOP_LOOPS (scop) = BITMAP_ALLOC (NULL);
+SCOP_LOOP_NEST (scop) = VEC_alloc (loop_p, heap, 3);
+SCOP_ADD_PARAMS (scop) = true;
+SCOP_PARAMS (scop) = VEC_alloc (name_tree, heap, 3);
+SCOP_PROG (scop) = cloog_program_malloc ();
+cloog_program_set_names (SCOP_PROG (scop), cloog_names_malloc ());
+SCOP_LOOP2CLOOG_LOOP (scop) = htab_create (10, hash_loop_to_cloog_loop,
+					     eq_loop_to_cloog_loop,
+					     free);
+SCOP_LIVEOUT_RENAMES (scop) = htab_create (10, rename_map_elt_info,
+					     eq_rename_map_elts, free);
+return scop;
+}
+/* Deletes SCOP.  */
+static void
+free_scop (scop_p scop)
+{
+int i;
+name_tree p;
+struct graphite_bb *gb;
+name_tree iv;
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gb); i++)
+free_graphite_bb (gb);
+VEC_free (graphite_bb_p, heap, SCOP_BBS (scop));
+BITMAP_FREE (SCOP_LOOPS (scop));
+VEC_free (loop_p, heap, SCOP_LOOP_NEST (scop));
+for (i = 0; VEC_iterate (name_tree, SCOP_OLDIVS (scop), i, iv); i++)
+free (iv);
+VEC_free (name_tree, heap, SCOP_OLDIVS (scop));
+for (i = 0; VEC_iterate (name_tree, SCOP_PARAMS (scop), i, p); i++)
+free (p);
+VEC_free (name_tree, heap, SCOP_PARAMS (scop));
+cloog_program_free (SCOP_PROG (scop));
+htab_delete (SCOP_LOOP2CLOOG_LOOP (scop));
+htab_delete (SCOP_LIVEOUT_RENAMES (scop));
+free_sese (SCOP_REGION (scop));
+XDELETE (scop);
+}
+/* Deletes all scops in SCOPS.  */
+static void
+free_scops (VEC (scop_p, heap) *scops)
+{
+int i;
+scop_p scop;
+for (i = 0; VEC_iterate (scop_p, scops, i, scop); i++)
+free_scop (scop);
+VEC_free (scop_p, heap, scops);
+}
+typedef enum gbb_type {
+GBB_UNKNOWN,
+GBB_LOOP_SING_EXIT_HEADER,
+GBB_LOOP_MULT_EXIT_HEADER,
+GBB_LOOP_EXIT,
+GBB_COND_HEADER,
+GBB_SIMPLE,
+GBB_LAST
+} gbb_type;
+/* Detect the type of BB.  Loop headers are only marked, if they are
+new.  This means their loop_father is different to LAST_LOOP.
+Otherwise they are treated like any other bb and their type can be
+any other type.  */
+static gbb_type
+get_bb_type (basic_block bb, struct loop *last_loop)
+{
+VEC (basic_block, heap) *dom;
+int nb_dom, nb_suc;
+struct loop *loop = bb->loop_father;
+/* Check, if we entry into a new loop. */
+if (loop != last_loop)
+{
+if (single_exit (loop) != NULL)
+return GBB_LOOP_SING_EXIT_HEADER;
+else if (loop->num != 0)
+return GBB_LOOP_MULT_EXIT_HEADER;
+else
+	return GBB_COND_HEADER;
+}
+dom = get_dominated_by (CDI_DOMINATORS, bb);
+nb_dom = VEC_length (basic_block, dom);
+VEC_free (basic_block, heap, dom);
+if (nb_dom == 0)
+return GBB_LAST;
+nb_suc = VEC_length (edge, bb->succs);
+if (nb_dom == 1 && nb_suc == 1)
+return GBB_SIMPLE;
+return GBB_COND_HEADER;
+}
+/* A SCoP detection region, defined using bbs as borders.
+All control flow touching this region, comes in passing basic_block ENTRY and
+leaves passing basic_block EXIT.  By using bbs instead of edges for the
+borders we are able to represent also regions that do not have a single
+entry or exit edge.
+But as they have a single entry basic_block and a single exit basic_block, we
+are able to generate for every sd_region a single entry and exit edge.
+1   2
+\ /
+3	<- entry
+|
+4
+/ \			This region contains: {3, 4, 5, 6, 7, 8}
+5   6
+|   |
+7   8
+\ /
+9	<- exit  */
+typedef struct sd_region_p
+{
+/* The entry bb dominates all bbs in the sd_region.  It is part of the
+region.  */
+basic_block entry;
+/* The exit bb postdominates all bbs in the sd_region, but is not
+part of the region.  */
+basic_block exit;
+} sd_region;
+DEF_VEC_O(sd_region);
+DEF_VEC_ALLOC_O(sd_region, heap);
+/* Moves the scops from SOURCE to TARGET and clean up SOURCE.  */
+static void
+move_sd_regions (VEC (sd_region, heap) **source, VEC (sd_region, heap) **target)
+{
+sd_region *s;
+int i;
+for (i = 0; VEC_iterate (sd_region, *source, i, s); i++)
+VEC_safe_push (sd_region, heap, *target, s);
+VEC_free (sd_region, heap, *source);
+}
+/* Return true when it is not possible to represent the upper bound of
+LOOP in the polyhedral representation.  */
+static bool
+graphite_cannot_represent_loop_niter (loop_p loop)
+{
+tree niter = number_of_latch_executions (loop);
+return chrec_contains_undetermined (niter)
+|| !scev_is_linear_expression (niter);
+}
+/* Store information needed by scopdet_* functions.  */
+struct scopdet_info
+{
+/* Where the last open scop would stop if the current BB is harmful.  */
+basic_block last;
+/* Where the next scop would start if the current BB is harmful.  */
+basic_block next;
+/* The bb or one of its children contains open loop exits.  That means
+loop exit nodes that are not surrounded by a loop dominated by bb.  */
+bool exits;
+/* The bb or one of its children contains only structures we can handle.  */
+bool difficult;
+};
+static struct scopdet_info build_scops_1 (basic_block, VEC (sd_region, heap) **,
+loop_p);
+/* Calculates BB infos. If bb is difficult we add valid SCoPs dominated by BB
+to SCOPS.  TYPE is the gbb_type of BB.  */
+static struct scopdet_info
+scopdet_basic_block_info (basic_block bb, VEC (sd_region, heap) **scops,
+			  gbb_type type)
+{
+struct loop *loop = bb->loop_father;
+struct scopdet_info result;
+gimple stmt;
+/* XXX: ENTRY_BLOCK_PTR could be optimized in later steps.  */
+stmt = harmful_stmt_in_bb (ENTRY_BLOCK_PTR, bb);
+result.difficult = (stmt != NULL);
+result.last = NULL;
+switch (type)
+{
+case GBB_LAST:
+result.next = NULL;
+result.exits = false;
+result.last = bb;
+/* Mark bbs terminating a SESE region difficult, if they start
+	 a condition.  */
+if (VEC_length (edge, bb->succs) > 1)
+	result.difficult = true;
+break;
+case GBB_SIMPLE:
+result.next = single_succ (bb);
+result.exits = false;
+result.last = bb;
+break;
+case GBB_LOOP_SING_EXIT_HEADER:
+{
+VEC (sd_region, heap) *tmp_scops = VEC_alloc (sd_region, heap,3);
+struct scopdet_info sinfo;
+sinfo = build_scops_1 (bb, &tmp_scops, loop);
+result.last = single_exit (bb->loop_father)->src;
+result.next = single_exit (bb->loop_father)->dest;
+/* If we do not dominate result.next, remove it.  It's either
+the EXIT_BLOCK_PTR, or another bb dominates it and will
+call the scop detection for this bb.  */
+if (!dominated_by_p (CDI_DOMINATORS, result.next, bb))
+	  result.next = NULL;
+	if (result.last->loop_father != loop)
+	  result.next = NULL;
+if (graphite_cannot_represent_loop_niter (loop))
+result.difficult = true;
+if (sinfo.difficult)
+move_sd_regions (&tmp_scops, scops);
+else
+VEC_free (sd_region, heap, tmp_scops);
+result.exits = false;
+result.difficult |= sinfo.difficult;
+break;
+}
+case GBB_LOOP_MULT_EXIT_HEADER:
+{
+/* XXX: For now we just do not join loops with multiple exits.  If the
+exits lead to the same bb it may be possible to join the loop.  */
+VEC (sd_region, heap) *tmp_scops = VEC_alloc (sd_region, heap, 3);
+VEC (edge, heap) *exits = get_loop_exit_edges (loop);
+edge e;
+int i;
+build_scops_1 (bb, &tmp_scops, loop);
+	/* Scan the code dominated by this loop.  This means all bbs, that are
+	   are dominated by a bb in this loop, but are not part of this loop.
+	   The easiest case:
+	     - The loop exit destination is dominated by the exit sources.
+	   TODO: We miss here the more complex cases:
+		  - The exit destinations are dominated by another bb inside the
+		    loop.
+		  - The loop dominates bbs, that are not exit destinations.  */
+for (i = 0; VEC_iterate (edge, exits, i, e); i++)
+if (e->src->loop_father == loop
+	      && dominated_by_p (CDI_DOMINATORS, e->dest, e->src))
+	    {
+	      /* Pass loop_outer to recognize e->dest as loop header in
+		 build_scops_1.  */
+	      if (e->dest->loop_father->header == e->dest)
+		build_scops_1 (e->dest, &tmp_scops,
+			       loop_outer (e->dest->loop_father));
+	      else
+		build_scops_1 (e->dest, &tmp_scops, e->dest->loop_father);
+	    }
+result.next = NULL;
+result.last = NULL;
+result.difficult = true;
+result.exits = false;
+move_sd_regions (&tmp_scops, scops);
+VEC_free (edge, heap, exits);
+break;
+}
+case GBB_COND_HEADER:
+{
+	VEC (sd_region, heap) *tmp_scops = VEC_alloc (sd_region, heap, 3);
+	struct scopdet_info sinfo;
+	VEC (basic_block, heap) *dominated;
+	int i;
+	basic_block dom_bb;
+	basic_block last_bb = NULL;
+	edge e;
+	result.exits = false;
+	/* First check the successors of BB, and check if it is possible to join
+	   the different branches.  */
+	for (i = 0; VEC_iterate (edge, bb->succs, i, e); i++)
+	  {
+	    /* Ignore loop exits.  They will be handled after the loop body.  */
+	    if (is_loop_exit (loop, e->dest))
+	      {
+		result.exits = true;
+		continue;
+	      }
+	    /* Do not follow edges that lead to the end of the
+	       conditions block.  For example, in
+|   0
+	       |  /|\
+	       | 1 2 |
+	       | | | |
+	       | 3 4 |
+	       |  \|/
+|   6
+	       the edge from 0 => 6.  Only check if all paths lead to
+	       the same node 6.  */
+	    if (!single_pred_p (e->dest))
+	      {
+		/* Check, if edge leads directly to the end of this
+		   condition.  */
+		if (!last_bb)
+		  {
+		    last_bb = e->dest;
+		  }
+		if (e->dest != last_bb)
+		  result.difficult = true;
+		continue;
+	      }
+	    if (!dominated_by_p (CDI_DOMINATORS, e->dest, bb))
+	      {
+		result.difficult = true;
+		continue;
+	      }
+	    sinfo = build_scops_1 (e->dest, &tmp_scops, loop);
+	    result.exits |= sinfo.exits;
+	    result.last = sinfo.last;
+	    result.difficult |= sinfo.difficult;
+	    /* Checks, if all branches end at the same point.
+	       If that is true, the condition stays joinable.
+	       Have a look at the example above.  */
+	    if (sinfo.last && single_succ_p (sinfo.last))
+	      {
+		basic_block next_tmp = single_succ (sinfo.last);
+		if (!last_bb)
+		    last_bb = next_tmp;
+		if (next_tmp != last_bb)
+		  result.difficult = true;
+	      }
+	    else
+	      result.difficult = true;
+	  }
+	/* If the condition is joinable.  */
+	if (!result.exits && !result.difficult)
+	  {
+	    /* Only return a next pointer if we dominate this pointer.
+	       Otherwise it will be handled by the bb dominating it.  */
+	    if (dominated_by_p (CDI_DOMINATORS, last_bb, bb) && last_bb != bb)
+	      result.next = last_bb;
+	    else
+	      result.next = NULL;
+	    VEC_free (sd_region, heap, tmp_scops);
+	    break;
+	  }
+	/* Scan remaining bbs dominated by BB.  */
+	dominated = get_dominated_by (CDI_DOMINATORS, bb);
+	for (i = 0; VEC_iterate (basic_block, dominated, i, dom_bb); i++)
+	  {
+	    /* Ignore loop exits: they will be handled after the loop body.  */
+	    if (loop_depth (find_common_loop (loop, dom_bb->loop_father))
+		< loop_depth (loop))
+	      {
+		result.exits = true;
+		continue;
+	      }
+	    /* Ignore the bbs processed above.  */
+	    if (single_pred_p (dom_bb) && single_pred (dom_bb) == bb)
+	      continue;
+	    if (loop_depth (loop) > loop_depth (dom_bb->loop_father))
+	      sinfo = build_scops_1 (dom_bb, &tmp_scops, loop_outer (loop));
+	    else
+	      sinfo = build_scops_1 (dom_bb, &tmp_scops, loop);
+	    result.exits |= sinfo.exits;
+	    result.difficult = true;
+	    result.last = NULL;
+	  }
+	VEC_free (basic_block, heap, dominated);
+	result.next = NULL;
+	move_sd_regions (&tmp_scops, scops);
+	break;
+}
+default:
+gcc_unreachable ();
+}
+return result;
+}
+/* Creates the SCoPs and writes entry and exit points for every SCoP.  */
+static struct scopdet_info
+build_scops_1 (basic_block current, VEC (sd_region, heap) **scops, loop_p loop)
+{
+bool in_scop = false;
+sd_region open_scop;
+struct scopdet_info sinfo;
+/* Initialize result.  */
+struct scopdet_info result;
+result.exits = false;
+result.difficult = false;
+result.next = NULL;
+result.last = NULL;
+open_scop.entry = NULL;
+open_scop.exit = NULL;
+sinfo.last = NULL;
+/* Loop over the dominance tree.  If we meet a difficult bb, close
+the current SCoP.  Loop and condition header start a new layer,
+and can only be added if all bbs in deeper layers are simple.  */
+while (current != NULL)
+{
+sinfo = scopdet_basic_block_info (current, scops, get_bb_type (current,
+								     loop));
+if (!in_scop && !(sinfo.exits || sinfo.difficult))
+{
+	  open_scop.entry = current;
+	  open_scop.exit = NULL;
+in_scop = true;
+}
+else if (in_scop && (sinfo.exits || sinfo.difficult))
+{
+	  open_scop.exit = current;
+VEC_safe_push (sd_region, heap, *scops, &open_scop);
+in_scop = false;
+}
+result.difficult |= sinfo.difficult;
+result.exits |= sinfo.exits;
+current = sinfo.next;
+}
+/* Try to close open_scop, if we are still in an open SCoP.  */
+if (in_scop)
+{
+int i;
+edge e;
+	for (i = 0; VEC_iterate (edge, sinfo.last->succs, i, e); i++)
+	  if (dominated_by_p (CDI_POST_DOMINATORS, sinfo.last, e->dest))
+open_scop.exit = e->dest;
+if (!open_scop.exit && open_scop.entry != sinfo.last)
+	  open_scop.exit = sinfo.last;
+	if (open_scop.exit)
+	  VEC_safe_push (sd_region, heap, *scops, &open_scop);
+}
+result.last = sinfo.last;
+return result;
+}
+/* Checks if a bb is contained in REGION.  */
+static bool
+bb_in_sd_region (basic_block bb, sd_region *region)
+{
+return dominated_by_p (CDI_DOMINATORS, bb, region->entry)
+	 && !(dominated_by_p (CDI_DOMINATORS, bb, region->exit)
+	      && !dominated_by_p (CDI_DOMINATORS, region->entry,
+				  region->exit));
+}
+/* Returns the single entry edge of REGION, if it does not exits NULL.  */
+static edge
+find_single_entry_edge (sd_region *region)
+{
+edge e;
+edge_iterator ei;
+edge entry = NULL;
+FOR_EACH_EDGE (e, ei, region->entry->preds)
+if (!bb_in_sd_region (e->src, region))
+{
+	if (entry)
+	  {
+	    entry = NULL;
+	    break;
+	  }
+	else
+	  entry = e;
+}
+return entry;
+}
+/* Returns the single exit edge of REGION, if it does not exits NULL.  */
+static edge
+find_single_exit_edge (sd_region *region)
+{
+edge e;
+edge_iterator ei;
+edge exit = NULL;
+FOR_EACH_EDGE (e, ei, region->exit->preds)
+if (bb_in_sd_region (e->src, region))
+{
+	if (exit)
+	  {
+	    exit = NULL;
+	    break;
+	  }
+	else
+	  exit = e;
+}
+return exit;
+}
+/* Create a single entry edge for REGION.  */
+static void
+create_single_entry_edge (sd_region *region)
+{
+if (find_single_entry_edge (region))
+return;
+/* There are multiple predecessors for bb_3
+|  1  2
+|  | /
+|  |/
+|  3	<- entry
+|  |\
+|  | |
+|  4 ^
+|  | |
+|  |/
+|  5
+There are two edges (1->3, 2->3), that point from outside into the region,
+and another one (5->3), a loop latch, lead to bb_3.
+We split bb_3.
+|  1  2
+|  | /
+|  |/
+|3.0
+|  |\     (3.0 -> 3.1) = single entry edge
+|3.1 |  	<- entry
+|  | |
+|  | |
+|  4 ^
+|  | |
+|  |/
+|  5
+If the loop is part of the SCoP, we have to redirect the loop latches.
+|  1  2
+|  | /
+|  |/
+|3.0
+|  |      (3.0 -> 3.1) = entry edge
+|3.1  	<- entry
+|  |\
+|  | |
+|  4 ^
+|  | |
+|  |/
+|  5  */
+if (region->entry->loop_father->header != region->entry
+|| dominated_by_p (CDI_DOMINATORS,
+			 loop_latch_edge (region->entry->loop_father)->src,
+			 region->exit))
+{
+edge forwarder = split_block_after_labels (region->entry);
+region->entry = forwarder->dest;
+}
+else
+/* This case is never executed, as the loop headers seem always to have a
+single edge pointing from outside into the loop.  */
+gcc_unreachable ();
+#ifdef ENABLE_CHECKING
+gcc_assert (find_single_entry_edge (region));
+#endif
+}
+/* Check if the sd_region, mentioned in EDGE, has no exit bb.  */
+static bool
+sd_region_without_exit (edge e)
+{
+sd_region *r = (sd_region *) e->aux;
+if (r)
+return r->exit == NULL;
+else
+return false;
+}
+/* Create a single exit edge for REGION.  */
+static void
+create_single_exit_edge (sd_region *region)
+{
+edge e;
+edge_iterator ei;
+edge forwarder = NULL;
+basic_block exit;
+if (find_single_exit_edge (region))
+return;
+/* We create a forwarder bb (5) for all edges leaving this region
+(3->5, 4->5).  All other edges leading to the same bb, are moved
+to a new bb (6).  If these edges where part of another region (2->5)
+we update the region->exit pointer, of this region.
+To identify which edge belongs to which region we depend on the e->aux
+pointer in every edge.  It points to the region of the edge or to NULL,
+if the edge is not part of any region.
+1 2 3 4   	1->5 no region, 		2->5 region->exit = 5,
+\| |/    	3->5 region->exit = NULL, 	4->5 region->exit = NULL
+5	<- exit
+changes to
+1 2 3 4   	1->6 no region, 			2->6 region->exit = 6,
+| | \/	3->5 no region,				4->5 no region,
+| |  5
+\| /	5->6 region->exit = 6
+	6
+Now there is only a single exit edge (5->6).  */
+exit = region->exit;
+region->exit = NULL;
+forwarder = make_forwarder_block (exit, &sd_region_without_exit, NULL);
+/* Unmark the edges, that are no longer exit edges.  */
+FOR_EACH_EDGE (e, ei, forwarder->src->preds)
+if (e->aux)
+e->aux = NULL;
+/* Mark the new exit edge.  */
+single_succ_edge (forwarder->src)->aux = region;
+/* Update the exit bb of all regions, where exit edges lead to
+forwarder->dest.  */
+FOR_EACH_EDGE (e, ei, forwarder->dest->preds)
+if (e->aux)
+((sd_region *) e->aux)->exit = forwarder->dest;
+#ifdef ENABLE_CHECKING
+gcc_assert (find_single_exit_edge (region));
+#endif
+}
+/* Unmark the exit edges of all REGIONS.
+See comment in "create_single_exit_edge". */
+static void
+unmark_exit_edges (VEC (sd_region, heap) *regions)
+{
+int i;
+sd_region *s;
+edge e;
+edge_iterator ei;
+for (i = 0; VEC_iterate (sd_region, regions, i, s); i++)
+FOR_EACH_EDGE (e, ei, s->exit->preds)
+e->aux = NULL;
+}
+/* Mark the exit edges of all REGIONS.
+See comment in "create_single_exit_edge". */
+static void
+mark_exit_edges (VEC (sd_region, heap) *regions)
+{
+int i;
+sd_region *s;
+edge e;
+edge_iterator ei;
+for (i = 0; VEC_iterate (sd_region, regions, i, s); i++)
+FOR_EACH_EDGE (e, ei, s->exit->preds)
+if (bb_in_sd_region (e->src, s))
+	e->aux = s;
+}
+/* Free and compute again all the dominators information.  */
+static inline void
+recompute_all_dominators (void)
+{
+mark_irreducible_loops ();
+free_dominance_info (CDI_DOMINATORS);
+free_dominance_info (CDI_POST_DOMINATORS);
+calculate_dominance_info (CDI_DOMINATORS);
+calculate_dominance_info (CDI_POST_DOMINATORS);
+}
+/* Verifies properties that GRAPHITE should maintain during translation.  */
+static inline void
+graphite_verify (void)
+{
+#ifdef ENABLE_CHECKING
+verify_loop_structure ();
+verify_dominators (CDI_DOMINATORS);
+verify_dominators (CDI_POST_DOMINATORS);
+verify_ssa (false);
+verify_loop_closed_ssa ();
+#endif
+}
+/* Create for all scop regions a single entry and a single exit edge.  */
+static void
+create_sese_edges (VEC (sd_region, heap) *regions)
+{
+int i;
+sd_region *s;
+for (i = 0; VEC_iterate (sd_region, regions, i, s); i++)
+create_single_entry_edge (s);
+mark_exit_edges (regions);
+for (i = 0; VEC_iterate (sd_region, regions, i, s); i++)
+create_single_exit_edge (s);
+unmark_exit_edges (regions);
+fix_loop_structure (NULL);
+#ifdef ENABLE_CHECKING
+verify_loop_structure ();
+verify_dominators (CDI_DOMINATORS);
+verify_ssa (false);
+#endif
+}
+/* Create graphite SCoPs from an array of scop detection regions.  */
+static void
+build_graphite_scops (VEC (sd_region, heap) *scop_regions)
+{
+int i;
+sd_region *s;
+for (i = 0; VEC_iterate (sd_region, scop_regions, i, s); i++)
+{
+edge entry = find_single_entry_edge (s);
+edge exit = find_single_exit_edge (s);
+scop_p scop = new_scop (entry, exit);
+VEC_safe_push (scop_p, heap, current_scops, scop);
+/* Are there overlapping SCoPs?  */
+#ifdef ENABLE_CHECKING
+	{
+	  int j;
+	  sd_region *s2;
+	  for (j = 0; VEC_iterate (sd_region, scop_regions, j, s2); j++)
+	    if (s != s2)
+	      gcc_assert (!bb_in_sd_region (s->entry, s2));
+	}
+#endif
+}
+}
+/* Find static control parts.  */
+static void
+build_scops (void)
+{
+struct loop *loop = current_loops->tree_root;
+VEC (sd_region, heap) *tmp_scops = VEC_alloc (sd_region, heap, 3);
+build_scops_1 (single_succ (ENTRY_BLOCK_PTR), &tmp_scops, loop);
+create_sese_edges (tmp_scops);
+build_graphite_scops (tmp_scops);
+VEC_free (sd_region, heap, tmp_scops);
+}
+/* Gather the basic blocks belonging to the SCOP.  */
+static void
+build_scop_bbs (scop_p scop)
+{
+basic_block *stack = XNEWVEC (basic_block, n_basic_blocks + 1);
+sbitmap visited = sbitmap_alloc (last_basic_block);
+int sp = 0;
+sbitmap_zero (visited);
+stack[sp++] = SCOP_ENTRY (scop);
+while (sp)
+{
+basic_block bb = stack[--sp];
+int depth = loop_depth (bb->loop_father);
+int num = bb->loop_father->num;
+edge_iterator ei;
+edge e;
+/* Scop's exit is not in the scop.  Exclude also bbs, which are
+	 dominated by the SCoP exit.  These are e.g. loop latches.  */
+if (TEST_BIT (visited, bb->index)
+	  || dominated_by_p (CDI_DOMINATORS, bb, SCOP_EXIT (scop))
+	  /* Every block in the scop is dominated by scop's entry.  */
+	  || !dominated_by_p (CDI_DOMINATORS, bb, SCOP_ENTRY (scop)))
+	continue;
+new_graphite_bb (scop, bb);
+SET_BIT (visited, bb->index);
+/* First push the blocks that have to be processed last.  Note
+	 that this means that the order in which the code is organized
+	 below is important: do not reorder the following code.  */
+FOR_EACH_EDGE (e, ei, bb->succs)
+	if (! TEST_BIT (visited, e->dest->index)
+	    && (int) loop_depth (e->dest->loop_father) < depth)
+	  stack[sp++] = e->dest;
+FOR_EACH_EDGE (e, ei, bb->succs)
+	if (! TEST_BIT (visited, e->dest->index)
+	    && (int) loop_depth (e->dest->loop_father) == depth
+	    && e->dest->loop_father->num != num)
+	  stack[sp++] = e->dest;
+FOR_EACH_EDGE (e, ei, bb->succs)
+	if (! TEST_BIT (visited, e->dest->index)
+	    && (int) loop_depth (e->dest->loop_father) == depth
+	    && e->dest->loop_father->num == num
+	    && EDGE_COUNT (e->dest->preds) > 1)
+	  stack[sp++] = e->dest;
+FOR_EACH_EDGE (e, ei, bb->succs)
+	if (! TEST_BIT (visited, e->dest->index)
+	    && (int) loop_depth (e->dest->loop_father) == depth
+	    && e->dest->loop_father->num == num
+	    && EDGE_COUNT (e->dest->preds) == 1)
+	  stack[sp++] = e->dest;
+FOR_EACH_EDGE (e, ei, bb->succs)
+	if (! TEST_BIT (visited, e->dest->index)
+	    && (int) loop_depth (e->dest->loop_father) > depth)
+	  stack[sp++] = e->dest;
+}
+free (stack);
+sbitmap_free (visited);
+}
+/* Returns the number of reduction phi nodes in LOOP.  */
+static int
+nb_reductions_in_loop (loop_p loop)
+{
+int res = 0;
+gimple_stmt_iterator gsi;
+for (gsi = gsi_start_phis (loop->header); !gsi_end_p (gsi); gsi_next (&gsi))
+{
+gimple phi = gsi_stmt (gsi);
+tree scev;
+affine_iv iv;
+if (!is_gimple_reg (PHI_RESULT (phi)))
+	continue;
+scev = analyze_scalar_evolution (loop, PHI_RESULT (phi));
+scev = instantiate_parameters (loop, scev);
+if (!simple_iv (loop, loop, PHI_RESULT (phi), &iv, true))
+	res++;
+}
+return res;
+}
+/* A LOOP is in normal form when it contains only one scalar phi node
+that defines the main induction variable of the loop, only one
+increment of the IV, and only one exit condition. */
+static tree
+graphite_loop_normal_form (loop_p loop)
+{
+struct tree_niter_desc niter;
+tree nit;
+gimple_seq stmts;
+edge exit = single_dom_exit (loop);
+bool known_niter = number_of_iterations_exit (loop, exit, &niter, false);
+gcc_assert (known_niter);
+nit = force_gimple_operand (unshare_expr (niter.niter), &stmts, true,
+			      NULL_TREE);
+if (stmts)
+gsi_insert_seq_on_edge_immediate (loop_preheader_edge (loop), stmts);
+/* One IV per loop.  */
+if (nb_reductions_in_loop (loop) > 0)
+return NULL_TREE;
+return canonicalize_loop_ivs (loop, NULL, &nit);
+}
+/* Record LOOP as occuring in SCOP.  Returns true when the operation
+was successful.  */
+static bool
+scop_record_loop (scop_p scop, loop_p loop)
+{
+tree induction_var;
+name_tree oldiv;
+if (bitmap_bit_p (SCOP_LOOPS (scop), loop->num))
+return true;
+bitmap_set_bit (SCOP_LOOPS (scop), loop->num);
+VEC_safe_push (loop_p, heap, SCOP_LOOP_NEST (scop), loop);
+induction_var = graphite_loop_normal_form (loop);
+if (!induction_var)
+return false;
+oldiv = XNEW (struct name_tree);
+oldiv->t = induction_var;
+oldiv->name = get_name (SSA_NAME_VAR (oldiv->t));
+oldiv->loop = loop;
+VEC_safe_push (name_tree, heap, SCOP_OLDIVS (scop), oldiv);
+return true;
+}
+/* Build the loop nests contained in SCOP.  Returns true when the
+operation was successful.  */
+static bool
+build_scop_loop_nests (scop_p scop)
+{
+unsigned i;
+basic_block bb;
+struct loop *loop0, *loop1;
+FOR_EACH_BB (bb)
+if (bb_in_sese_p (bb, SCOP_REGION (scop)))
+{
+	struct loop *loop = bb->loop_father;
+	/* Only add loops if they are completely contained in the SCoP.  */
+	if (loop->header == bb
+	    && bb_in_sese_p (loop->latch, SCOP_REGION (scop)))
+	  {
+	    if (!scop_record_loop (scop, loop))
+	      return false;
+	  }
+}
+/* Make sure that the loops in the SCOP_LOOP_NEST are ordered.  It
+can be the case that an inner loop is inserted before an outer
+loop.  To avoid this, semi-sort once.  */
+for (i = 0; VEC_iterate (loop_p, SCOP_LOOP_NEST (scop), i, loop0); i++)
+{
+if (VEC_length (loop_p, SCOP_LOOP_NEST (scop)) == i + 1)
+	break;
+loop1 = VEC_index (loop_p, SCOP_LOOP_NEST (scop), i + 1);
+if (loop0->num > loop1->num)
+	{
+	  VEC_replace (loop_p, SCOP_LOOP_NEST (scop), i, loop1);
+	  VEC_replace (loop_p, SCOP_LOOP_NEST (scop), i + 1, loop0);
+	}
+}
+return true;
+}
+/* Calculate the number of loops around LOOP in the SCOP.  */
+static inline int
+nb_loops_around_loop_in_scop (struct loop *l, scop_p scop)
+{
+int d = 0;
+for (; loop_in_sese_p (l, SCOP_REGION (scop)); d++, l = loop_outer (l));
+return d;
+}
+/* Calculate the number of loops around GB in the current SCOP.  */
+int
+nb_loops_around_gb (graphite_bb_p gb)
+{
+return nb_loops_around_loop_in_scop (gbb_loop (gb), GBB_SCOP (gb));
+}
+/* Returns the dimensionality of an enclosing loop iteration domain
+with respect to enclosing SCoP for a given data reference REF.  The
+returned dimensionality is homogeneous (depth of loop nest + number
+of SCoP parameters + const).  */
+int
+ref_nb_loops (data_reference_p ref)
+{
+loop_p loop = loop_containing_stmt (DR_STMT (ref));
+scop_p scop = DR_SCOP (ref);
+return nb_loops_around_loop_in_scop (loop, scop) + scop_nb_params (scop) + 2;
+}
+/* Build dynamic schedules for all the BBs. */
+static void
+build_scop_dynamic_schedules (scop_p scop)
+{
+int i, dim, loop_num, row, col;
+graphite_bb_p gb;
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gb); i++)
+{
+loop_num = GBB_BB (gb)->loop_father->num;
+if (loop_num != 0)
+{
+dim = nb_loops_around_gb (gb);
+GBB_DYNAMIC_SCHEDULE (gb) = cloog_matrix_alloc (dim, dim);
+for (row = 0; row < GBB_DYNAMIC_SCHEDULE (gb)->NbRows; row++)
+for (col = 0; col < GBB_DYNAMIC_SCHEDULE (gb)->NbColumns; col++)
+if (row == col)
+value_set_si (GBB_DYNAMIC_SCHEDULE (gb)->p[row][col], 1);
+else
+value_set_si (GBB_DYNAMIC_SCHEDULE (gb)->p[row][col], 0);
+}
+else
+GBB_DYNAMIC_SCHEDULE (gb) = NULL;
+}
+}
+/* Returns the number of loops that are identical at the beginning of
+the vectors A and B.  */
+static int
+compare_prefix_loops (VEC (loop_p, heap) *a, VEC (loop_p, heap) *b)
+{
+int i;
+loop_p ea;
+int lb;
+if (!a || !b)
+return 0;
+lb = VEC_length (loop_p, b);
+for (i = 0; VEC_iterate (loop_p, a, i, ea); i++)
+if (i >= lb
+	|| ea != VEC_index (loop_p, b, i))
+return i;
+return 0;
+}
+/* Build for BB the static schedule.
+The STATIC_SCHEDULE is defined like this:
+A
+for (i: ...)
+{
+for (j: ...)
+{
+B
+C
+}
+for (k: ...)
+{
+D
+E
+}
+}
+F
+Static schedules for A to F:
+DEPTH
+0 1 2
+A 0
+B 1 0 0
+C 1 0 1
+D 1 1 0
+E 1 1 1
+F 2
+*/
+static void
+build_scop_canonical_schedules (scop_p scop)
+{
+int i;
+graphite_bb_p gb;
+int nb_loops = scop_nb_loops (scop);
+lambda_vector static_schedule = lambda_vector_new (nb_loops + 1);
+VEC (loop_p, heap) *loops_previous = NULL;
+/* We have to start schedules at 0 on the first component and
+because we cannot compare_prefix_loops against a previous loop,
+prefix will be equal to zero, and that index will be
+incremented before copying.  */
+static_schedule[0] = -1;
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gb); i++)
+{
+int prefix = compare_prefix_loops (loops_previous, GBB_LOOPS (gb));
+int nb = gbb_nb_loops (gb);
+loops_previous = GBB_LOOPS (gb);
+memset (&(static_schedule[prefix + 1]), 0, sizeof (int) * (nb_loops - prefix));
+++static_schedule[prefix];
+GBB_STATIC_SCHEDULE (gb) = lambda_vector_new (nb + 1);
+lambda_vector_copy (static_schedule,
+			  GBB_STATIC_SCHEDULE (gb), nb + 1);
+}
+}
+/* Build the LOOPS vector for all bbs in SCOP.  */
+static void
+build_bb_loops (scop_p scop)
+{
+graphite_bb_p gb;
+int i;
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gb); i++)
+{
+loop_p loop;
+int depth;
+depth = nb_loops_around_gb (gb) - 1;
+GBB_LOOPS (gb) = VEC_alloc (loop_p, heap, 3);
+VEC_safe_grow_cleared (loop_p, heap, GBB_LOOPS (gb), depth + 1);
+loop = GBB_BB (gb)->loop_father;
+while (scop_contains_loop (scop, loop))
+{
+VEC_replace (loop_p, GBB_LOOPS (gb), depth, loop);
+loop = loop_outer (loop);
+depth--;
+}
+}
+}
+/* Get the index for parameter VAR in SCOP.  */
+static int
+param_index (tree var, scop_p scop)
+{
+int i;
+name_tree p;
+name_tree nvar;
+gcc_assert (TREE_CODE (var) == SSA_NAME);
+for (i = 0; VEC_iterate (name_tree, SCOP_PARAMS (scop), i, p); i++)
+if (p->t == var)
+return i;
+gcc_assert (SCOP_ADD_PARAMS (scop));
+nvar = XNEW (struct name_tree);
+nvar->t = var;
+nvar->name = NULL;
+VEC_safe_push (name_tree, heap, SCOP_PARAMS (scop), nvar);
+return VEC_length (name_tree, SCOP_PARAMS (scop)) - 1;
+}
+/* Scan EXPR and translate it to an inequality vector INEQ that will
+be added, or subtracted, in the constraint domain matrix C at row
+R.  K is the number of columns for loop iterators in C. */
+static void
+scan_tree_for_params (scop_p s, tree e, CloogMatrix *c, int r, Value k,
+		      bool subtract)
+{
+int cst_col, param_col;
+if (e == chrec_dont_know)
+return;
+switch (TREE_CODE (e))
+{
+case POLYNOMIAL_CHREC:
+{
+	tree left = CHREC_LEFT (e);
+	tree right = CHREC_RIGHT (e);
+	int var = CHREC_VARIABLE (e);
+	if (TREE_CODE (right) != INTEGER_CST)
+	  return;
+	if (c)
+	  {
+int loop_col = scop_gimple_loop_depth (s, get_loop (var)) + 1;
+if (subtract)
+value_sub_int (c->p[r][loop_col], c->p[r][loop_col],
+int_cst_value (right));
+else
+value_add_int (c->p[r][loop_col], c->p[r][loop_col],
+int_cst_value (right));
+	  }
+	switch (TREE_CODE (left))
+	  {
+	  case POLYNOMIAL_CHREC:
+	    scan_tree_for_params (s, left, c, r, k, subtract);
+return;
+	  case INTEGER_CST:
+	    /* Constant part.  */
+	    if (c)
+	      {
+int v = int_cst_value (left);
+cst_col = c->NbColumns - 1;
+if (v < 0)
+{
+v = -v;
+subtract = subtract ? false : true;
+}
+if (subtract)
+value_sub_int (c->p[r][cst_col], c->p[r][cst_col], v);
+else
+value_add_int (c->p[r][cst_col], c->p[r][cst_col], v);
+	      }
+	    return;
+	  default:
+	    scan_tree_for_params (s, left, c, r, k, subtract);
+	    return;
+	  }
+}
+break;
+case MULT_EXPR:
+if (chrec_contains_symbols (TREE_OPERAND (e, 0)))
+	{
+	  if (c)
+	    {
+	      Value val;
+	      gcc_assert (host_integerp (TREE_OPERAND (e, 1), 0));
+	      value_init (val);
+	      value_set_si (val, int_cst_value (TREE_OPERAND (e, 1)));
+	      value_multiply (k, k, val);
+	      value_clear (val);
+	    }
+	  scan_tree_for_params (s, TREE_OPERAND (e, 0), c, r, k, subtract);
+	}
+else
+	{
+	  if (c)
+	    {
+	      Value val;
+	      gcc_assert (host_integerp (TREE_OPERAND (e, 0), 0));
+	      value_init (val);
+	      value_set_si (val, int_cst_value (TREE_OPERAND (e, 0)));
+	      value_multiply (k, k, val);
+	      value_clear (val);
+	    }
+	  scan_tree_for_params (s, TREE_OPERAND (e, 1), c, r, k, subtract);
+	}
+break;
+case PLUS_EXPR:
+case POINTER_PLUS_EXPR:
+scan_tree_for_params (s, TREE_OPERAND (e, 0), c, r, k, subtract);
+scan_tree_for_params (s, TREE_OPERAND (e, 1), c, r, k, subtract);
+break;
+case MINUS_EXPR:
+scan_tree_for_params (s, TREE_OPERAND (e, 0), c, r, k, subtract);
+scan_tree_for_params (s, TREE_OPERAND (e, 1), c, r, k, !subtract);
+break;
+case NEGATE_EXPR:
+scan_tree_for_params (s, TREE_OPERAND (e, 0), c, r, k, !subtract);
+break;
+case SSA_NAME:
+param_col = param_index (e, s);
+if (c)
+	{
+param_col += c->NbColumns - scop_nb_params (s) - 1;
+if (subtract)
+	    value_subtract (c->p[r][param_col], c->p[r][param_col], k);
+else
+	    value_addto (c->p[r][param_col], c->p[r][param_col], k);
+	}
+break;
+case INTEGER_CST:
+if (c)
+	{
+int v = int_cst_value (e);
+	  cst_col = c->NbColumns - 1;
+if (v < 0)
+{
+v = -v;
+subtract = subtract ? false : true;
+}
+if (subtract)
+value_sub_int (c->p[r][cst_col], c->p[r][cst_col], v);
+else
+value_add_int (c->p[r][cst_col], c->p[r][cst_col], v);
+	}
+break;
+CASE_CONVERT:
+case NON_LVALUE_EXPR:
+scan_tree_for_params (s, TREE_OPERAND (e, 0), c, r, k, subtract);
+break;
+default:
+gcc_unreachable ();
+break;
+}
+}
+/* Data structure for idx_record_params.  */
+struct irp_data
+{
+struct loop *loop;
+scop_p scop;
+};
+/* For a data reference with an ARRAY_REF as its BASE, record the
+parameters occurring in IDX.  DTA is passed in as complementary
+information, and is used by the automatic walker function.  This
+function is a callback for for_each_index.  */
+static bool
+idx_record_params (tree base, tree *idx, void *dta)
+{
+struct irp_data *data = (struct irp_data *) dta;
+if (TREE_CODE (base) != ARRAY_REF)
+return true;
+if (TREE_CODE (*idx) == SSA_NAME)
+{
+tree scev;
+scop_p scop = data->scop;
+struct loop *loop = data->loop;
+Value one;
+scev = analyze_scalar_evolution (loop, *idx);
+scev = instantiate_scev (block_before_scop (scop), loop, scev);
+value_init (one);
+value_set_si (one, 1);
+scan_tree_for_params (scop, scev, NULL, 0, one, false);
+value_clear (one);
+}
+return true;
+}
+/* Find parameters with respect to SCOP in BB. We are looking in memory
+access functions, conditions and loop bounds.  */
+static void
+find_params_in_bb (scop_p scop, graphite_bb_p gb)
+{
+int i;
+data_reference_p dr;
+gimple stmt;
+loop_p father = GBB_BB (gb)->loop_father;
+for (i = 0; VEC_iterate (data_reference_p, GBB_DATA_REFS (gb), i, dr); i++)
+{
+struct irp_data irp;
+irp.loop = father;
+irp.scop = scop;
+for_each_index (&dr->ref, idx_record_params, &irp);
+}
+/* Find parameters in conditional statements.  */
+for (i = 0; VEC_iterate (gimple, GBB_CONDITIONS (gb), i, stmt); i++)
+{
+Value one;
+loop_p loop = father;
+tree lhs, rhs;
+lhs = gimple_cond_lhs (stmt);
+lhs = analyze_scalar_evolution (loop, lhs);
+lhs = instantiate_scev (block_before_scop (scop), loop, lhs);
+rhs = gimple_cond_rhs (stmt);
+rhs = analyze_scalar_evolution (loop, rhs);
+rhs = instantiate_scev (block_before_scop (scop), loop, rhs);
+value_init (one);
+scan_tree_for_params (scop, lhs, NULL, 0, one, false);
+value_set_si (one, 1);
+scan_tree_for_params (scop, rhs, NULL, 0, one, false);
+value_clear (one);
+}
+}
+/* Saves in NV the name of variable P->T.  */
+static void
+save_var_name (char **nv, int i, name_tree p)
+{
+const char *name = get_name (SSA_NAME_VAR (p->t));
+if (name)
+{
+int len = strlen (name) + 16;
+nv[i] = XNEWVEC (char, len);
+snprintf (nv[i], len, "%s_%d", name, SSA_NAME_VERSION (p->t));
+}
+else
+{
+nv[i] = XNEWVEC (char, 16);
+snprintf (nv[i], 2 + 16, "T_%d", SSA_NAME_VERSION (p->t));
+}
+p->name = nv[i];
+}
+/* Return the maximal loop depth in SCOP.  */
+static int
+scop_max_loop_depth (scop_p scop)
+{
+int i;
+graphite_bb_p gbb;
+int max_nb_loops = 0;
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gbb); i++)
+{
+int nb_loops = gbb_nb_loops (gbb);
+if (max_nb_loops < nb_loops)
+max_nb_loops = nb_loops;
+}
+return max_nb_loops;
+}
+/* Initialize Cloog's parameter names from the names used in GIMPLE.
+Initialize Cloog's iterator names, using 'graphite_iterator_%d'
+from 0 to scop_nb_loops (scop).  */
+static void
+initialize_cloog_names (scop_p scop)
+{
+int i, nb_params = VEC_length (name_tree, SCOP_PARAMS (scop));
+char **params = XNEWVEC (char *, nb_params);
+int nb_iterators = scop_max_loop_depth (scop);
+int nb_scattering= cloog_program_nb_scattdims (SCOP_PROG (scop));
+char **iterators = XNEWVEC (char *, nb_iterators * 2);
+char **scattering = XNEWVEC (char *, nb_scattering);
+name_tree p;
+for (i = 0; VEC_iterate (name_tree, SCOP_PARAMS (scop), i, p); i++)
+save_var_name (params, i, p);
+cloog_names_set_nb_parameters (cloog_program_names (SCOP_PROG (scop)),
+				 nb_params);
+cloog_names_set_parameters (cloog_program_names (SCOP_PROG (scop)),
+			      params);
+for (i = 0; i < nb_iterators; i++)
+{
+int len = 18 + 16;
+iterators[i] = XNEWVEC (char, len);
+snprintf (iterators[i], len, "graphite_iterator_%d", i);
+}
+cloog_names_set_nb_iterators (cloog_program_names (SCOP_PROG (scop)),
+				nb_iterators);
+cloog_names_set_iterators (cloog_program_names (SCOP_PROG (scop)),
+			     iterators);
+for (i = 0; i < nb_scattering; i++)
+{
+int len = 2 + 16;
+scattering[i] = XNEWVEC (char, len);
+snprintf (scattering[i], len, "s_%d", i);
+}
+cloog_names_set_nb_scattering (cloog_program_names (SCOP_PROG (scop)),
+				 nb_scattering);
+cloog_names_set_scattering (cloog_program_names (SCOP_PROG (scop)),
+			      scattering);
+}
+/* Record the parameters used in the SCOP.  A variable is a parameter
+in a scop if it does not vary during the execution of that scop.  */
+static void
+find_scop_parameters (scop_p scop)
+{
+graphite_bb_p gb;
+unsigned i;
+struct loop *loop;
+Value one;
+value_init (one);
+value_set_si (one, 1);
+/* Find the parameters used in the loop bounds.  */
+for (i = 0; VEC_iterate (loop_p, SCOP_LOOP_NEST (scop), i, loop); i++)
+{
+tree nb_iters = number_of_latch_executions (loop);
+if (!chrec_contains_symbols (nb_iters))
+	continue;
+nb_iters = analyze_scalar_evolution (loop, nb_iters);
+nb_iters = instantiate_scev (block_before_scop (scop), loop, nb_iters);
+scan_tree_for_params (scop, nb_iters, NULL, 0, one, false);
+}
+value_clear (one);
+/* Find the parameters used in data accesses.  */
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gb); i++)
+find_params_in_bb (scop, gb);
+SCOP_ADD_PARAMS (scop) = false;
+}
+/* Build the context constraints for SCOP: constraints and relations
+on parameters.  */
+static void
+build_scop_context (scop_p scop)
+{
+int nb_params = scop_nb_params (scop);
+CloogMatrix *matrix = cloog_matrix_alloc (1, nb_params + 2);
+/* Insert '0 >= 0' in the context matrix, as it is not allowed to be
+empty. */
+value_set_si (matrix->p[0][0], 1);
+value_set_si (matrix->p[0][nb_params + 1], 0);
+cloog_program_set_context (SCOP_PROG (scop),
+			     cloog_domain_matrix2domain (matrix));
+cloog_matrix_free (matrix);
+}
+/* Returns a graphite_bb from BB.  */
+static inline graphite_bb_p
+gbb_from_bb (basic_block bb)
+{
+return (graphite_bb_p) bb->aux;
+}
+/* Builds the constraint matrix for LOOP in SCOP.  NB_OUTER_LOOPS is the
+number of loops surrounding LOOP in SCOP.  OUTER_CSTR gives the
+constraints matrix for the surrounding loops.  */
+static void
+build_loop_iteration_domains (scop_p scop, struct loop *loop,
+CloogMatrix *outer_cstr, int nb_outer_loops)
+{
+int i, j, row;
+CloogMatrix *cstr;
+graphite_bb_p gb;
+int nb_rows = outer_cstr->NbRows + 1;
+int nb_cols = outer_cstr->NbColumns + 1;
+/* Last column of CSTR is the column of constants.  */
+int cst_col = nb_cols - 1;
+/* The column for the current loop is just after the columns of
+other outer loops.  */
+int loop_col = nb_outer_loops + 1;
+tree nb_iters = number_of_latch_executions (loop);
+/* When the number of iterations is a constant or a parameter, we
+add a constraint for the upper bound of the loop.  So add a row
+to the constraint matrix before allocating it.  */
+if (TREE_CODE (nb_iters) == INTEGER_CST
+|| !chrec_contains_undetermined (nb_iters))
+nb_rows++;
+cstr = cloog_matrix_alloc (nb_rows, nb_cols);
+/* Copy the outer constraints.  */
+for (i = 0; i < outer_cstr->NbRows; i++)
+{
+/* Copy the eq/ineq and loops columns.  */
+for (j = 0; j < loop_col; j++)
+value_assign (cstr->p[i][j], outer_cstr->p[i][j]);
+/* Leave an empty column in CSTR for the current loop, and then
+	 copy the parameter columns.  */
+for (j = loop_col; j < outer_cstr->NbColumns; j++)
+value_assign (cstr->p[i][j + 1], outer_cstr->p[i][j]);
+}
+/* 0 <= loop_i */
+row = outer_cstr->NbRows;
+value_set_si (cstr->p[row][0], 1);
+value_set_si (cstr->p[row][loop_col], 1);
+/* loop_i <= nb_iters */
+if (TREE_CODE (nb_iters) == INTEGER_CST)
+{
+row++;
+value_set_si (cstr->p[row][0], 1);
+value_set_si (cstr->p[row][loop_col], -1);
+value_set_si (cstr->p[row][cst_col],
+		    int_cst_value (nb_iters));
+}
+else if (!chrec_contains_undetermined (nb_iters))
+{
+/* Otherwise nb_iters contains parameters: scan the nb_iters
+	 expression and build its matrix representation.  */
+Value one;
+row++;
+value_set_si (cstr->p[row][0], 1);
+value_set_si (cstr->p[row][loop_col], -1);
+nb_iters = analyze_scalar_evolution (loop, nb_iters);
+nb_iters = instantiate_scev (block_before_scop (scop), loop, nb_iters);
+value_init (one);
+value_set_si (one, 1);
+scan_tree_for_params (scop, nb_iters, cstr, row, one, false);
+value_clear (one);
+}
+else
+gcc_unreachable ();
+if (loop->inner && loop_in_sese_p (loop->inner, SCOP_REGION (scop)))
+build_loop_iteration_domains (scop, loop->inner, cstr, nb_outer_loops + 1);
+/* Only go to the next loops, if we are not at the outermost layer.  These
+have to be handled seperately, as we can be sure, that the chain at this
+layer will be connected.  */
+if (nb_outer_loops != 0 && loop->next && loop_in_sese_p (loop->next,
+							   SCOP_REGION (scop)))
+build_loop_iteration_domains (scop, loop->next, outer_cstr, nb_outer_loops);
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gb); i++)
+if (gbb_loop (gb) == loop)
+GBB_DOMAIN (gb) = cloog_matrix_copy (cstr);
+cloog_matrix_free (cstr);
+}
+/* Add conditions to the domain of GB.  */
+static void
+add_conditions_to_domain (graphite_bb_p gb)
+{
+unsigned int i,j;
+gimple stmt;
+VEC (gimple, heap) *conditions = GBB_CONDITIONS (gb);
+CloogMatrix *domain = GBB_DOMAIN (gb);
+scop_p scop = GBB_SCOP (gb);
+unsigned nb_rows;
+unsigned nb_cols;
+unsigned nb_new_rows = 0;
+unsigned row;
+if (VEC_empty (gimple, conditions))
+return;
+if (domain)
+{
+nb_rows = domain->NbRows;
+nb_cols = domain->NbColumns;
+}
+else
+{
+nb_rows = 0;
+nb_cols = nb_loops_around_gb (gb) + scop_nb_params (scop) + 2;
+}
+/* Count number of necessary new rows to add the conditions to the
+domain.  */
+for (i = 0; VEC_iterate (gimple, conditions, i, stmt); i++)
+{
+switch (gimple_code (stmt))
+{
+case GIMPLE_COND:
+{
+enum tree_code code = gimple_cond_code (stmt);
+switch (code)
+{
+case NE_EXPR:
+case EQ_EXPR:
+/* NE and EQ statements are not supported right know. */
+gcc_unreachable ();
+break;
+case LT_EXPR:
+case GT_EXPR:
+case LE_EXPR:
+case GE_EXPR:
+nb_new_rows++;
+break;
+default:
+gcc_unreachable ();
+break;
+}
+break;
+}
+case SWITCH_EXPR:
+/* Switch statements are not supported right know.  */
+gcc_unreachable ();
+break;
+default:
+gcc_unreachable ();
+break;
+}
+}
+/* Enlarge the matrix.  */
+{
+CloogMatrix *new_domain;
+new_domain = cloog_matrix_alloc (nb_rows + nb_new_rows, nb_cols);
+if (domain)
+{
+	for (i = 0; i < nb_rows; i++)
+	  for (j = 0; j < nb_cols; j++)
+	    value_assign (new_domain->p[i][j], domain->p[i][j]);
+	cloog_matrix_free (domain);
+}
+domain = new_domain;
+GBB_DOMAIN (gb) = new_domain;
+}
+/* Add the conditions to the new enlarged domain matrix.  */
+row = nb_rows;
+for (i = 0; VEC_iterate (gimple, conditions, i, stmt); i++)
+{
+switch (gimple_code (stmt))
+{
+case GIMPLE_COND:
+{
+Value one;
+enum tree_code code;
+tree left;
+tree right;
+loop_p loop = GBB_BB (gb)->loop_father;
+left = gimple_cond_lhs (stmt);
+right = gimple_cond_rhs (stmt);
+left = analyze_scalar_evolution (loop, left);
+right = analyze_scalar_evolution (loop, right);
+left = instantiate_scev (block_before_scop (scop), loop, left);
+right = instantiate_scev (block_before_scop (scop), loop, right);
+code = gimple_cond_code (stmt);
+/* The conditions for ELSE-branches are inverted.  */
+if (VEC_index (gimple, gb->condition_cases, i) == NULL)
+code = invert_tree_comparison (code, false);
+switch (code)
+{
+case NE_EXPR:
+/* NE statements are not supported right know. */
+gcc_unreachable ();
+break;
+case EQ_EXPR:
+value_set_si (domain->p[row][0], 1);
+value_init (one);
+value_set_si (one, 1);
+scan_tree_for_params (scop, left, domain, row, one, true);
+value_set_si (one, 1);
+scan_tree_for_params (scop, right, domain, row, one, false);
+row++;
+value_set_si (domain->p[row][0], 1);
+value_set_si (one, 1);
+scan_tree_for_params (scop, left, domain, row, one, false);
+value_set_si (one, 1);
+scan_tree_for_params (scop, right, domain, row, one, true);
+value_clear (one);
+row++;
+break;
+case LT_EXPR:
+value_set_si (domain->p[row][0], 1);
+value_init (one);
+value_set_si (one, 1);
+scan_tree_for_params (scop, left, domain, row, one, true);
+value_set_si (one, 1);
+scan_tree_for_params (scop, right, domain, row, one, false);
+value_sub_int (domain->p[row][nb_cols - 1],
+domain->p[row][nb_cols - 1], 1);
+value_clear (one);
+row++;
+break;
+case GT_EXPR:
+value_set_si (domain->p[row][0], 1);
+value_init (one);
+value_set_si (one, 1);
+scan_tree_for_params (scop, left, domain, row, one, false);
+value_set_si (one, 1);
+scan_tree_for_params (scop, right, domain, row, one, true);
+value_sub_int (domain->p[row][nb_cols - 1],
+domain->p[row][nb_cols - 1], 1);
+value_clear (one);
+row++;
+break;
+case LE_EXPR:
+value_set_si (domain->p[row][0], 1);
+value_init (one);
+value_set_si (one, 1);
+scan_tree_for_params (scop, left, domain, row, one, true);
+value_set_si (one, 1);
+scan_tree_for_params (scop, right, domain, row, one, false);
+value_clear (one);
+row++;
+break;
+case GE_EXPR:
+value_set_si (domain->p[row][0], 1);
+value_init (one);
+value_set_si (one, 1);
+scan_tree_for_params (scop, left, domain, row, one, false);
+value_set_si (one, 1);
+scan_tree_for_params (scop, right, domain, row, one, true);
+value_clear (one);
+row++;
+break;
+default:
+gcc_unreachable ();
+break;
+}
+break;
+}
+case GIMPLE_SWITCH:
+/* Switch statements are not supported right know.  */
+gcc_unreachable ();
+break;
+default:
+gcc_unreachable ();
+break;
+}
+}
+}
+/* Returns true when PHI defines an induction variable in the loop
+containing the PHI node.  */
+static bool
+phi_node_is_iv (gimple phi)
+{
+loop_p loop = gimple_bb (phi)->loop_father;
+tree scev = analyze_scalar_evolution (loop, gimple_phi_result (phi));
+return tree_contains_chrecs (scev, NULL);
+}
+/* Returns true when BB contains scalar phi nodes that are not an
+induction variable of a loop.  */
+static bool
+bb_contains_non_iv_scalar_phi_nodes (basic_block bb)
+{
+gimple phi = NULL;
+gimple_stmt_iterator si;
+for (si = gsi_start_phis (bb); !gsi_end_p (si); gsi_next (&si))
+if (is_gimple_reg (gimple_phi_result (gsi_stmt (si))))
+{
+	/* Store the unique scalar PHI node: at this point, loops
+	   should be in cannonical form, so we expect to see at most
+	   one scalar phi node in the loop header.  */
+	if (phi
+	    || bb != bb->loop_father->header)
+	  return true;
+	phi = gsi_stmt (si);
+}
+if (!phi
+|| phi_node_is_iv (phi))
+return false;
+return true;
+}
+/* Helper recursive function.  Record in CONDITIONS and CASES all
+conditions from 'if's and 'switch'es occurring in BB from SCOP.
+Returns false when the conditions contain scalar computations that
+depend on the condition, i.e. when there are scalar phi nodes on
+the junction after the condition.  Only the computations occurring
+on memory can be handled in the polyhedral model: operations that
+define scalar evolutions in conditions, that can potentially be
+used to index memory, can't be handled by the polyhedral model.  */
+static bool
+build_scop_conditions_1 (VEC (gimple, heap) **conditions,
+			 VEC (gimple, heap) **cases, basic_block bb,
+			 scop_p scop)
+{
+bool res = true;
+int i, j;
+graphite_bb_p gbb;
+basic_block bb_child, bb_iter;
+VEC (basic_block, heap) *dom;
+gimple stmt;
+/* Make sure we are in the SCoP.  */
+if (!bb_in_sese_p (bb, SCOP_REGION (scop)))
+return true;
+if (bb_contains_non_iv_scalar_phi_nodes (bb))
+return false;
+gbb = gbb_from_bb (bb);
+if (gbb)
+{
+GBB_CONDITIONS (gbb) = VEC_copy (gimple, heap, *conditions);
+GBB_CONDITION_CASES (gbb) = VEC_copy (gimple, heap, *cases);
+}
+dom = get_dominated_by (CDI_DOMINATORS, bb);
+stmt = last_stmt (bb);
+if (stmt)
+{
+VEC (edge, gc) *edges;
+edge e;
+switch (gimple_code (stmt))
+	{
+	case GIMPLE_COND:
+	  edges = bb->succs;
+	  for (i = 0; VEC_iterate (edge, edges, i, e); i++)
+	    if ((dominated_by_p (CDI_DOMINATORS, e->dest, bb))
+		&& VEC_length (edge, e->dest->preds) == 1)
+	      {
+		/* Remove the scanned block from the dominator successors.  */
+		for (j = 0; VEC_iterate (basic_block, dom, j, bb_iter); j++)
+		  if (bb_iter == e->dest)
+		    {
+		      VEC_unordered_remove (basic_block, dom, j);
+		      break;
+		    }
+		/* Recursively scan the then or else part.  */
+		if (e->flags & EDGE_TRUE_VALUE)
+		  VEC_safe_push (gimple, heap, *cases, stmt);
+		else
+		  {
+		    gcc_assert (e->flags & EDGE_FALSE_VALUE);
+		    VEC_safe_push (gimple, heap, *cases, NULL);
+		  }
+		VEC_safe_push (gimple, heap, *conditions, stmt);
+		if (!build_scop_conditions_1 (conditions, cases, e->dest, scop))
+		  {
+		    res = false;
+		    goto done;
+		  }
+		VEC_pop (gimple, *conditions);
+		VEC_pop (gimple, *cases);
+	      }
+	  break;
+	case GIMPLE_SWITCH:
+	  {
+	    unsigned i;
+	    gimple_stmt_iterator gsi_search_gimple_label;
+	    for (i = 0; i < gimple_switch_num_labels (stmt); ++i)
+	      {
+		basic_block bb_iter;
+		size_t k;
+		size_t n_cases = VEC_length (gimple, *conditions);
+		unsigned n = gimple_switch_num_labels (stmt);
+		bb_child = label_to_block
+		  (CASE_LABEL (gimple_switch_label (stmt, i)));
+		for (k = 0; k < n; k++)
+		  if (i != k
+		      && label_to_block
+		      (CASE_LABEL (gimple_switch_label (stmt, k))) == bb_child)
+		    break;
+		/* Switches with multiple case values for the same
+		   block are not handled.  */
+		if (k != n
+		    /* Switch cases with more than one predecessor are
+		       not handled.  */
+		    || VEC_length (edge, bb_child->preds) != 1)
+		  {
+		    res = false;
+		    goto done;
+		  }
+		/* Recursively scan the corresponding 'case' block.  */
+		for (gsi_search_gimple_label = gsi_start_bb (bb_child);
+		     !gsi_end_p (gsi_search_gimple_label);
+		     gsi_next (&gsi_search_gimple_label))
+		  {
+		    gimple label = gsi_stmt (gsi_search_gimple_label);
+		    if (gimple_code (label) == GIMPLE_LABEL)
+		      {
+			tree t = gimple_label_label (label);
+			gcc_assert (t == gimple_switch_label (stmt, i));
+			VEC_replace (gimple, *cases, n_cases, label);
+			break;
+		      }
+		  }
+		if (!build_scop_conditions_1 (conditions, cases, bb_child, scop))
+		  {
+		    res = false;
+		    goto done;
+		  }
+		/* Remove the scanned block from the dominator successors.  */
+		for (j = 0; VEC_iterate (basic_block, dom, j, bb_iter); j++)
+		  if (bb_iter == bb_child)
+		    {
+		      VEC_unordered_remove (basic_block, dom, j);
+		      break;
+		    }
+	      }
+	    VEC_pop (gimple, *conditions);
+	    VEC_pop (gimple, *cases);
+	    break;
+	  }
+	default:
+	  break;
+}
+}
+/* Scan all immediate dominated successors.  */
+for (i = 0; VEC_iterate (basic_block, dom, i, bb_child); i++)
+if (!build_scop_conditions_1 (conditions, cases, bb_child, scop))
+{
+	res = false;
+	goto done;
+}
+done:
+VEC_free (basic_block, heap, dom);
+return res;
+}
+/* Record all conditions from SCOP.
+Returns false when the conditions contain scalar computations that
+depend on the condition, i.e. when there are scalar phi nodes on
+the junction after the condition.  Only the computations occurring
+on memory can be handled in the polyhedral model: operations that
+define scalar evolutions in conditions, that can potentially be
+used to index memory, can't be handled by the polyhedral model.  */
+static bool
+build_scop_conditions (scop_p scop)
+{
+bool res;
+VEC (gimple, heap) *conditions = NULL;
+VEC (gimple, heap) *cases = NULL;
+res = build_scop_conditions_1 (&conditions, &cases, SCOP_ENTRY (scop), scop);
+VEC_free (gimple, heap, conditions);
+VEC_free (gimple, heap, cases);
+return res;
+}
+/* Traverses all the GBBs of the SCOP and add their constraints to the
+iteration domains.  */
+static void
+add_conditions_to_constraints (scop_p scop)
+{
+int i;
+graphite_bb_p gbb;
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gbb); i++)
+add_conditions_to_domain (gbb);
+}
+/* Build the current domain matrix: the loops belonging to the current
+SCOP, and that vary for the execution of the current basic block.
+Returns false if there is no loop in SCOP.  */
+static bool
+build_scop_iteration_domain (scop_p scop)
+{
+struct loop *loop;
+CloogMatrix *outer_cstr;
+int i;
+/* Build cloog loop for all loops, that are in the uppermost loop layer of
+this SCoP.  */
+for (i = 0; VEC_iterate (loop_p, SCOP_LOOP_NEST (scop), i, loop); i++)
+if (!loop_in_sese_p (loop_outer (loop), SCOP_REGION (scop)))
+{
+/* The outermost constraints is a matrix that has:
+-first column: eq/ineq boolean
+-last column: a constant
+-scop_nb_params columns for the parameters used in the scop.  */
+	outer_cstr = cloog_matrix_alloc (0, scop_nb_params (scop) + 2);
+	build_loop_iteration_domains (scop, loop, outer_cstr, 0);
+	cloog_matrix_free (outer_cstr);
+}
+return (i != 0);
+}
+/* Initializes an equation CY of the access matrix using the
+information for a subscript from AF, relatively to the loop
+indexes from LOOP_NEST and parameter indexes from PARAMS.  NDIM is
+the dimension of the array access, i.e. the number of
+subscripts.  Returns true when the operation succeeds.  */
+static bool
+build_access_matrix_with_af (tree af, lambda_vector cy,
+			     scop_p scop, int ndim)
+{
+int param_col;
+switch (TREE_CODE (af))
+{
+case POLYNOMIAL_CHREC:
+{
+struct loop *outer_loop;
+	tree left = CHREC_LEFT (af);
+	tree right = CHREC_RIGHT (af);
+	int var;
+	if (TREE_CODE (right) != INTEGER_CST)
+	  return false;
+outer_loop = get_loop (CHREC_VARIABLE (af));
+var = nb_loops_around_loop_in_scop (outer_loop, scop);
+	cy[var] = int_cst_value (right);
+	switch (TREE_CODE (left))
+	  {
+	  case POLYNOMIAL_CHREC:
+	    return build_access_matrix_with_af (left, cy, scop, ndim);
+	  case INTEGER_CST:
+	    cy[ndim - 1] = int_cst_value (left);
+	    return true;
+	  default:
+	    return build_access_matrix_with_af (left, cy, scop, ndim);
+	  }
+}
+case PLUS_EXPR:
+build_access_matrix_with_af (TREE_OPERAND (af, 0), cy, scop, ndim);
+build_access_matrix_with_af (TREE_OPERAND (af, 1), cy, scop, ndim);
+return true;
+case MINUS_EXPR:
+build_access_matrix_with_af (TREE_OPERAND (af, 0), cy, scop, ndim);
+build_access_matrix_with_af (TREE_OPERAND (af, 1), cy, scop, ndim);
+return true;
+case INTEGER_CST:
+cy[ndim - 1] = int_cst_value (af);
+return true;
+case SSA_NAME:
+param_col = param_index (af, scop);
+cy [ndim - scop_nb_params (scop) + param_col - 1] = 1;
+return true;
+default:
+/* FIXME: access_fn can have parameters.  */
+return false;
+}
+}
+/* Initialize the access matrix in the data reference REF with respect
+to the loop nesting LOOP_NEST.  Return true when the operation
+succeeded.  */
+static bool
+build_access_matrix (data_reference_p ref, graphite_bb_p gb)
+{
+int i, ndim = DR_NUM_DIMENSIONS (ref);
+struct access_matrix *am = GGC_NEW (struct access_matrix);
+AM_MATRIX (am) = VEC_alloc (lambda_vector, gc, ndim);
+DR_SCOP (ref) = GBB_SCOP (gb);
+for (i = 0; i < ndim; i++)
+{
+lambda_vector v = lambda_vector_new (ref_nb_loops (ref));
+scop_p scop = GBB_SCOP (gb);
+tree af = DR_ACCESS_FN (ref, i);
+if (!build_access_matrix_with_af (af, v, scop, ref_nb_loops (ref)))
+	return false;
+VEC_quick_push (lambda_vector, AM_MATRIX (am), v);
+}
+DR_ACCESS_MATRIX (ref) = am;
+return true;
+}
+/* Build the access matrices for the data references in the SCOP.  */
+static void
+build_scop_data_accesses (scop_p scop)
+{
+int i;
+graphite_bb_p gb;
+/* FIXME: Construction of access matrix is disabled until some
+pass, like the data dependence analysis, is using it.  */
+return;
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gb); i++)
+{
+int j;
+data_reference_p dr;
+/* Construct the access matrix for each data ref, with respect to
+	 the loop nest of the current BB in the considered SCOP.  */
+for (j = 0;
+	   VEC_iterate (data_reference_p, GBB_DATA_REFS (gb), j, dr);
+	   j++)
+	{
+	  bool res = build_access_matrix (dr, gb);
+	  /* FIXME: At this point the DRs should always have an affine
+	     form.  For the moment this fails as build_access_matrix
+	     does not build matrices with parameters.  */
+	  gcc_assert (res);
+	}
+}
+}
+/* Returns the tree variable from the name NAME that was given in
+Cloog representation.  All the parameters are stored in PARAMS, and
+all the loop induction variables are stored in IVSTACK.
+FIXME: This is a hack, and Cloog should be fixed to not work with
+variable names represented as "char *string", but with void
+pointers that could be casted back to a tree.  The only problem in
+doing that is that Cloog's pretty printer still assumes that
+variable names are char *strings.  The solution would be to have a
+function pointer for pretty-printing that can be redirected to be
+print_generic_stmt in our case, or fprintf by default.
+???  Too ugly to live.  */
+static tree
+clast_name_to_gcc (const char *name, VEC (name_tree, heap) *params,
+		   loop_iv_stack ivstack)
+{
+int i;
+name_tree t;
+tree iv;
+if (params)
+for (i = 0; VEC_iterate (name_tree, params, i, t); i++)
+if (!strcmp (name, t->name))
+	return t->t;
+iv = loop_iv_stack_get_iv_from_name (ivstack, name);
+if (iv)
+return iv;
+gcc_unreachable ();
+}
+/* Returns the maximal precision type for expressions E1 and E2.  */
+static inline tree
+max_precision_type (tree e1, tree e2)
+{
+tree type1 = TREE_TYPE (e1);
+tree type2 = TREE_TYPE (e2);
+return TYPE_PRECISION (type1) > TYPE_PRECISION (type2) ? type1 : type2;
+}
+static tree
+clast_to_gcc_expression (tree, struct clast_expr *, VEC (name_tree, heap) *,
+			 loop_iv_stack);
+/* Converts a Cloog reduction expression R with reduction operation OP
+to a GCC expression tree of type TYPE.  PARAMS is a vector of
+parameters of the scop, and IVSTACK contains the stack of induction
+variables.  */
+static tree
+clast_to_gcc_expression_red (tree type, enum tree_code op,
+			     struct clast_reduction *r,
+			     VEC (name_tree, heap) *params,
+			     loop_iv_stack ivstack)
+{
+int i;
+tree res = clast_to_gcc_expression (type, r->elts[0], params, ivstack);
+for (i = 1; i < r->n; i++)
+{
+tree t = clast_to_gcc_expression (type, r->elts[i], params, ivstack);
+res = fold_build2 (op, type, res, t);
+}
+return res;
+}
+/* Converts a Cloog AST expression E back to a GCC expression tree of
+type TYPE.  PARAMS is a vector of parameters of the scop, and
+IVSTACK contains the stack of induction variables.  */
+static tree
+clast_to_gcc_expression (tree type, struct clast_expr *e,
+			 VEC (name_tree, heap) *params,
+			 loop_iv_stack ivstack)
+{
+switch (e->type)
+{
+case expr_term:
+{
+	struct clast_term *t = (struct clast_term *) e;
+	if (t->var)
+	  {
+	    if (value_one_p (t->val))
+	      {
+		tree name = clast_name_to_gcc (t->var, params, ivstack);
+		return fold_convert (type, name);
+	      }
+	    else if (value_mone_p (t->val))
+	      {
+		tree name = clast_name_to_gcc (t->var, params, ivstack);
+		name = fold_convert (type, name);
+		return fold_build1 (NEGATE_EXPR, type, name);
+	      }
+	    else
+	      {
+		tree name = clast_name_to_gcc (t->var, params, ivstack);
+		tree cst = gmp_cst_to_tree (type, t->val);
+		name = fold_convert (type, name);
+		return fold_build2 (MULT_EXPR, type, cst, name);
+	      }
+	  }
+	else
+	  return gmp_cst_to_tree (type, t->val);
+}
+case expr_red:
+{
+struct clast_reduction *r = (struct clast_reduction *) e;
+switch (r->type)
+{
+	  case clast_red_sum:
+	    return clast_to_gcc_expression_red (type, PLUS_EXPR, r, params, ivstack);
+	  case clast_red_min:
+	    return clast_to_gcc_expression_red (type, MIN_EXPR, r, params, ivstack);
+	  case clast_red_max:
+	    return clast_to_gcc_expression_red (type, MAX_EXPR, r, params, ivstack);
+	  default:
+	    gcc_unreachable ();
+}
+break;
+}
+case expr_bin:
+{
+	struct clast_binary *b = (struct clast_binary *) e;
+	struct clast_expr *lhs = (struct clast_expr *) b->LHS;
+	tree tl = clast_to_gcc_expression (type, lhs, params, ivstack);
+	tree tr = gmp_cst_to_tree (type, b->RHS);
+	switch (b->type)
+	  {
+	  case clast_bin_fdiv:
+	    return fold_build2 (FLOOR_DIV_EXPR, type, tl, tr);
+	  case clast_bin_cdiv:
+	    return fold_build2 (CEIL_DIV_EXPR, type, tl, tr);
+	  case clast_bin_div:
+	    return fold_build2 (EXACT_DIV_EXPR, type, tl, tr);
+	  case clast_bin_mod:
+	    return fold_build2 (TRUNC_MOD_EXPR, type, tl, tr);
+	  default:
+	    gcc_unreachable ();
+	  }
+}
+default:
+gcc_unreachable ();
+}
+return NULL_TREE;
+}
+/* Returns the type for the expression E.  */
+static tree
+gcc_type_for_clast_expr (struct clast_expr *e,
+			 VEC (name_tree, heap) *params,
+			 loop_iv_stack ivstack)
+{
+switch (e->type)
+{
+case expr_term:
+{
+	struct clast_term *t = (struct clast_term *) e;
+	if (t->var)
+	  return TREE_TYPE (clast_name_to_gcc (t->var, params, ivstack));
+	else
+	  return NULL_TREE;
+}
+case expr_red:
+{
+struct clast_reduction *r = (struct clast_reduction *) e;
+	if (r->n == 1)
+	  return gcc_type_for_clast_expr (r->elts[0], params, ivstack);
+	else
+	  {
+	    int i;
+	    for (i = 0; i < r->n; i++)
+	      {
+		tree type = gcc_type_for_clast_expr (r->elts[i], params, ivstack);
+		if (type)
+		  return type;
+	      }
+	    return NULL_TREE;
+	  }
+}
+case expr_bin:
+{
+	struct clast_binary *b = (struct clast_binary *) e;
+	struct clast_expr *lhs = (struct clast_expr *) b->LHS;
+	return gcc_type_for_clast_expr (lhs, params, ivstack);
+}
+default:
+gcc_unreachable ();
+}
+return NULL_TREE;
+}
+/* Returns the type for the equation CLEQ.  */
+static tree
+gcc_type_for_clast_eq (struct clast_equation *cleq,
+		       VEC (name_tree, heap) *params,
+		       loop_iv_stack ivstack)
+{
+tree type = gcc_type_for_clast_expr (cleq->LHS, params, ivstack);
+if (type)
+return type;
+return gcc_type_for_clast_expr (cleq->RHS, params, ivstack);
+}
+/* Translates a clast equation CLEQ to a tree.  */
+static tree
+graphite_translate_clast_equation (scop_p scop,
+				   struct clast_equation *cleq,
+				   loop_iv_stack ivstack)
+{
+enum tree_code comp;
+tree type = gcc_type_for_clast_eq (cleq, SCOP_PARAMS (scop), ivstack);
+tree lhs = clast_to_gcc_expression (type, cleq->LHS, SCOP_PARAMS (scop), ivstack);
+tree rhs = clast_to_gcc_expression (type, cleq->RHS, SCOP_PARAMS (scop), ivstack);
+if (cleq->sign == 0)
+comp = EQ_EXPR;
+else if (cleq->sign > 0)
+comp = GE_EXPR;
+else
+comp = LE_EXPR;
+return fold_build2 (comp, type, lhs, rhs);
+}
+/* Creates the test for the condition in STMT.  */
+static tree
+graphite_create_guard_cond_expr (scop_p scop, struct clast_guard *stmt,
+				 loop_iv_stack ivstack)
+{
+tree cond = NULL;
+int i;
+for (i = 0; i < stmt->n; i++)
+{
+tree eq = graphite_translate_clast_equation (scop, &stmt->eq[i], ivstack);
+if (cond)
+	cond = fold_build2 (TRUTH_AND_EXPR, TREE_TYPE (eq), cond, eq);
+else
+	cond = eq;
+}
+return cond;
+}
+/* Creates a new if region corresponding to Cloog's guard.  */
+static edge
+graphite_create_new_guard (scop_p scop, edge entry_edge,
+			   struct clast_guard *stmt,
+			   loop_iv_stack ivstack)
+{
+tree cond_expr = graphite_create_guard_cond_expr (scop, stmt, ivstack);
+edge exit_edge = create_empty_if_region_on_edge (entry_edge, cond_expr);
+return exit_edge;
+}
+/* Walks a CLAST and returns the first statement in the body of a
+loop.  */
+static struct clast_user_stmt *
+clast_get_body_of_loop (struct clast_stmt *stmt)
+{
+if (!stmt
+|| CLAST_STMT_IS_A (stmt, stmt_user))
+return (struct clast_user_stmt *) stmt;
+if (CLAST_STMT_IS_A (stmt, stmt_for))
+return clast_get_body_of_loop (((struct clast_for *) stmt)->body);
+if (CLAST_STMT_IS_A (stmt, stmt_guard))
+return clast_get_body_of_loop (((struct clast_guard *) stmt)->then);
+if (CLAST_STMT_IS_A (stmt, stmt_block))
+return clast_get_body_of_loop (((struct clast_block *) stmt)->body);
+gcc_unreachable ();
+}
+/* Returns the induction variable for the loop that gets translated to
+STMT.  */
+static tree
+gcc_type_for_iv_of_clast_loop (struct clast_for *stmt_for)
+{
+struct clast_user_stmt *stmt = clast_get_body_of_loop ((struct clast_stmt *) stmt_for);
+const char *cloog_iv = stmt_for->iterator;
+CloogStatement *cs = stmt->statement;
+graphite_bb_p gbb = (graphite_bb_p) cloog_statement_usr (cs);
+return gcc_type_for_cloog_iv (cloog_iv, gbb);
+}
+/* Creates a new LOOP corresponding to Cloog's STMT.  Inserts an induction
+variable for the new LOOP.  New LOOP is attached to CFG starting at
+ENTRY_EDGE.  LOOP is inserted into the loop tree and becomes the child
+loop of the OUTER_LOOP.  */
+static struct loop *
+graphite_create_new_loop (scop_p scop, edge entry_edge,
+			  struct clast_for *stmt, loop_iv_stack ivstack,
+			  loop_p outer)
+{
+tree type = gcc_type_for_iv_of_clast_loop (stmt);
+VEC (name_tree, heap) *params = SCOP_PARAMS (scop);
+tree lb = clast_to_gcc_expression (type, stmt->LB, params, ivstack);
+tree ub = clast_to_gcc_expression (type, stmt->UB, params, ivstack);
+tree stride = gmp_cst_to_tree (type, stmt->stride);
+tree ivvar = create_tmp_var (type, "graphiteIV");
+tree iv_before;
+loop_p loop = create_empty_loop_on_edge
+(entry_edge, lb, stride, ub, ivvar, &iv_before,
+outer ? outer : entry_edge->src->loop_father);
+add_referenced_var (ivvar);
+loop_iv_stack_push_iv (ivstack, iv_before, stmt->iterator);
+return loop;
+}
+/* Rename the SSA_NAMEs used in STMT and that appear in IVSTACK.  */
+static void
+rename_variables_in_stmt (gimple stmt, htab_t map)
+{
+ssa_op_iter iter;
+use_operand_p use_p;
+FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE)
+{
+tree use = USE_FROM_PTR (use_p);
+tree new_name = get_new_name_from_old_name (map, use);
+replace_exp (use_p, new_name);
+}
+update_stmt (stmt);
+}
+/* Returns true if SSA_NAME is a parameter of SCOP.  */
+static bool
+is_parameter (scop_p scop, tree ssa_name)
+{
+int i;
+VEC (name_tree, heap) *params = SCOP_PARAMS (scop);
+name_tree param;
+for (i = 0; VEC_iterate (name_tree, params, i, param); i++)
+if (param->t == ssa_name)
+return true;
+return false;
+}
+/* Returns true if NAME is an induction variable.  */
+static bool
+is_iv (tree name)
+{
+return gimple_code (SSA_NAME_DEF_STMT (name)) == GIMPLE_PHI;
+}
+static void expand_scalar_variables_stmt (gimple, basic_block, scop_p,
+					  htab_t);
+static tree
+expand_scalar_variables_expr (tree, tree, enum tree_code, tree, basic_block,
+			      scop_p, htab_t, gimple_stmt_iterator *);
+/* Copies at GSI all the scalar computations on which the ssa_name OP0
+depends on in the SCOP: these are all the scalar variables used in
+the definition of OP0, that are defined outside BB and still in the
+SCOP, i.e. not a parameter of the SCOP.  The expression that is
+returned contains only induction variables from the generated code:
+MAP contains the induction variables renaming mapping, and is used
+to translate the names of induction variables.  */
+static tree
+expand_scalar_variables_ssa_name (tree op0, basic_block bb,
+				  scop_p scop, htab_t map,
+				  gimple_stmt_iterator *gsi)
+{
+tree var0, var1, type;
+gimple def_stmt;
+enum tree_code subcode;
+if (is_parameter (scop, op0)
+|| is_iv (op0))
+return get_new_name_from_old_name (map, op0);
+def_stmt = SSA_NAME_DEF_STMT (op0);
+if (gimple_bb (def_stmt) == bb)
+{
+/* If the defining statement is in the basic block already
+	 we do not need to create a new expression for it, we
+	 only need to ensure its operands are expanded.  */
+expand_scalar_variables_stmt (def_stmt, bb, scop, map);
+return get_new_name_from_old_name (map, op0);
+}
+else
+{
+if (gimple_code (def_stmt) != GIMPLE_ASSIGN
+	  || !bb_in_sese_p (gimple_bb (def_stmt), SCOP_REGION (scop)))
+	return get_new_name_from_old_name (map, op0);
+var0 = gimple_assign_rhs1 (def_stmt);
+subcode = gimple_assign_rhs_code (def_stmt);
+var1 = gimple_assign_rhs2 (def_stmt);
+type = gimple_expr_type (def_stmt);
+return expand_scalar_variables_expr (type, var0, subcode, var1, bb, scop,
+					   map, gsi);
+}
+}
+/* Copies at GSI all the scalar computations on which the expression
+OP0 CODE OP1 depends on in the SCOP: these are all the scalar
+variables used in OP0 and OP1, defined outside BB and still defined
+in the SCOP, i.e. not a parameter of the SCOP.  The expression that
+is returned contains only induction variables from the generated
+code: MAP contains the induction variables renaming mapping, and is
+used to translate the names of induction variables.  */
+static tree
+expand_scalar_variables_expr (tree type, tree op0, enum tree_code code,
+			      tree op1, basic_block bb, scop_p scop,
+			      htab_t map, gimple_stmt_iterator *gsi)
+{
+if (TREE_CODE_CLASS (code) == tcc_constant
+|| TREE_CODE_CLASS (code) == tcc_declaration)
+return op0;
+/* For data references we have to duplicate also its memory
+indexing.  */
+if (TREE_CODE_CLASS (code) == tcc_reference)
+{
+switch (code)
+	{
+	case INDIRECT_REF:
+	  {
+	    tree old_name = TREE_OPERAND (op0, 0);
+	    tree expr = expand_scalar_variables_ssa_name
+	      (old_name, bb, scop, map, gsi);
+	    tree new_name = force_gimple_operand_gsi (gsi, expr, true, NULL,
+						      true, GSI_SAME_STMT);
+	    set_symbol_mem_tag (SSA_NAME_VAR (new_name),
+				symbol_mem_tag (SSA_NAME_VAR (old_name)));
+	    return fold_build1 (code, type, new_name);
+	  }
+	case ARRAY_REF:
+	  {
+	    tree op00 = TREE_OPERAND (op0, 0);
+	    tree op01 = TREE_OPERAND (op0, 1);
+	    tree op02 = TREE_OPERAND (op0, 2);
+	    tree op03 = TREE_OPERAND (op0, 3);
+	    tree base = expand_scalar_variables_expr
+	      (TREE_TYPE (op00), op00, TREE_CODE (op00), NULL, bb, scop,
+	       map, gsi);
+	    tree subscript = expand_scalar_variables_expr
+	      (TREE_TYPE (op01), op01, TREE_CODE (op01), NULL, bb, scop,
+	       map, gsi);
+	    return build4 (ARRAY_REF, type, base, subscript, op02, op03);
+	  }
+	default:
+	  /* The above cases should catch everything.  */
+	  gcc_unreachable ();
+	}
+}
+if (TREE_CODE_CLASS (code) == tcc_unary)
+{
+tree op0_type = TREE_TYPE (op0);
+enum tree_code op0_code = TREE_CODE (op0);
+tree op0_expr = expand_scalar_variables_expr (op0_type, op0, op0_code,
+						    NULL, bb, scop, map, gsi);
+return fold_build1 (code, type, op0_expr);
+}
+if (TREE_CODE_CLASS (code) == tcc_binary)
+{
+tree op0_type = TREE_TYPE (op0);
+enum tree_code op0_code = TREE_CODE (op0);
+tree op0_expr = expand_scalar_variables_expr (op0_type, op0, op0_code,
+						    NULL, bb, scop, map, gsi);
+tree op1_type = TREE_TYPE (op1);
+enum tree_code op1_code = TREE_CODE (op1);
+tree op1_expr = expand_scalar_variables_expr (op1_type, op1, op1_code,
+						    NULL, bb, scop, map, gsi);
+return fold_build2 (code, type, op0_expr, op1_expr);
+}
+if (code == SSA_NAME)
+return expand_scalar_variables_ssa_name (op0, bb, scop, map, gsi);
+gcc_unreachable ();
+return NULL;
+}
+/* Copies at the beginning of BB all the scalar computations on which
+STMT depends on in the SCOP: these are all the scalar variables used
+in STMT, defined outside BB and still defined in the SCOP, i.e. not a
+parameter of the SCOP.  The expression that is returned contains
+only induction variables from the generated code: MAP contains the
+induction variables renaming mapping, and is used to translate the
+names of induction variables.  */
+static void
+expand_scalar_variables_stmt (gimple stmt, basic_block bb, scop_p scop,
+			      htab_t map)
+{
+ssa_op_iter iter;
+use_operand_p use_p;
+gimple_stmt_iterator gsi = gsi_after_labels (bb);
+FOR_EACH_SSA_USE_OPERAND (use_p, stmt, iter, SSA_OP_USE)
+{
+tree use = USE_FROM_PTR (use_p);
+tree type = TREE_TYPE (use);
+enum tree_code code = TREE_CODE (use);
+tree use_expr = expand_scalar_variables_expr (type, use, code, NULL, bb,
+						    scop, map, &gsi);
+if (use_expr != use)
+	{
+	  tree new_use =
+	    force_gimple_operand_gsi (&gsi, use_expr, true, NULL,
+				      true, GSI_NEW_STMT);
+	  replace_exp (use_p, new_use);
+	}
+}
+update_stmt (stmt);
+}
+/* Copies at the beginning of BB all the scalar computations on which
+BB depends on in the SCOP: these are all the scalar variables used
+in BB, defined outside BB and still defined in the SCOP, i.e. not a
+parameter of the SCOP.  The expression that is returned contains
+only induction variables from the generated code: MAP contains the
+induction variables renaming mapping, and is used to translate the
+names of induction variables.  */
+static void
+expand_scalar_variables (basic_block bb, scop_p scop, htab_t map)
+{
+gimple_stmt_iterator gsi;
+for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi);)
+{
+gimple stmt = gsi_stmt (gsi);
+expand_scalar_variables_stmt (stmt, bb, scop, map);
+gsi_next (&gsi);
+}
+}
+/* Rename all the SSA_NAMEs from block BB according to the MAP.  */
+static void
+rename_variables (basic_block bb, htab_t map)
+{
+gimple_stmt_iterator gsi;
+for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+rename_variables_in_stmt (gsi_stmt (gsi), map);
+}
+/* Remove condition from BB.  */
+static void
+remove_condition (basic_block bb)
+{
+gimple last = last_stmt (bb);
+if (last && gimple_code (last) == GIMPLE_COND)
+{
+gimple_stmt_iterator gsi = gsi_last_bb (bb);
+gsi_remove (&gsi, true);
+}
+}
+/* Returns the first successor edge of BB with EDGE_TRUE_VALUE flag set.  */
+static edge
+get_true_edge_from_guard_bb (basic_block bb)
+{
+edge e;
+edge_iterator ei;
+FOR_EACH_EDGE (e, ei, bb->succs)
+if (e->flags & EDGE_TRUE_VALUE)
+return e;
+gcc_unreachable ();
+return NULL;
+}
+/* Returns the first successor edge of BB with EDGE_TRUE_VALUE flag cleared.  */
+static edge
+get_false_edge_from_guard_bb (basic_block bb)
+{
+edge e;
+edge_iterator ei;
+FOR_EACH_EDGE (e, ei, bb->succs)
+if (!(e->flags & EDGE_TRUE_VALUE))
+return e;
+gcc_unreachable ();
+return NULL;
+}
+/* Inserts in MAP a tuple (OLD_NAME, NEW_NAME) for the induction
+variables of the loops around GBB in SCOP, i.e. GBB_LOOPS.
+NEW_NAME is obtained from IVSTACK.  IVSTACK has the same stack
+ordering as GBB_LOOPS.  */
+static void
+build_iv_mapping (loop_iv_stack ivstack, htab_t map, gbb_p gbb, scop_p scop)
+{
+int i;
+name_tree iv;
+PTR *slot;
+for (i = 0; VEC_iterate (name_tree, SCOP_OLDIVS (scop), i, iv); i++)
+{
+struct rename_map_elt tmp;
+if (!flow_bb_inside_loop_p (iv->loop, GBB_BB (gbb)))
+	continue;
+tmp.old_name = iv->t;
+slot = htab_find_slot (map, &tmp, INSERT);
+if (!*slot)
+	{
+	  tree new_name = loop_iv_stack_get_iv (ivstack,
+						gbb_loop_index (gbb, iv->loop));
+	  *slot = new_rename_map_elt (iv->t, new_name);
+	}
+}
+}
+/* Register in MAP the tuple (old_name, new_name).  */
+static void
+register_old_and_new_names (htab_t map, tree old_name, tree new_name)
+{
+struct rename_map_elt tmp;
+PTR *slot;
+tmp.old_name = old_name;
+slot = htab_find_slot (map, &tmp, INSERT);
+if (!*slot)
+*slot = new_rename_map_elt (old_name, new_name);
+}
+/* Create a duplicate of the basic block BB.  NOTE: This does not
+preserve SSA form.  */
+static void
+graphite_copy_stmts_from_block (basic_block bb, basic_block new_bb, htab_t map)
+{
+gimple_stmt_iterator gsi, gsi_tgt;
+gsi_tgt = gsi_start_bb (new_bb);
+for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+{
+def_operand_p def_p;
+ssa_op_iter op_iter;
+int region;
+gimple stmt = gsi_stmt (gsi);
+gimple copy;
+if (gimple_code (stmt) == GIMPLE_LABEL)
+	continue;
+/* Create a new copy of STMT and duplicate STMT's virtual
+	 operands.  */
+copy = gimple_copy (stmt);
+gsi_insert_after (&gsi_tgt, copy, GSI_NEW_STMT);
+mark_symbols_for_renaming (copy);
+region = lookup_stmt_eh_region (stmt);
+if (region >= 0)
+	add_stmt_to_eh_region (copy, region);
+gimple_duplicate_stmt_histograms (cfun, copy, cfun, stmt);
+/* Create new names for all the definitions created by COPY and
+	 add replacement mappings for each new name.  */
+FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_DEF)
+	{
+	  tree old_name = DEF_FROM_PTR (def_p);
+	  tree new_name = create_new_def_for (old_name, copy, def_p);
+	  register_old_and_new_names (map, old_name, new_name);
+	}
+}
+}
+/* Records in SCOP_LIVEOUT_RENAMES the names that are live out of
+the SCOP and that appear in the RENAME_MAP.  */
+static void
+register_scop_liveout_renames (scop_p scop, htab_t rename_map)
+{
+int i;
+sese region = SCOP_REGION (scop);
+for (i = 0; i < SESE_NUM_VER (region); i++)
+if (bitmap_bit_p (SESE_LIVEOUT (region), i)
+	&& is_gimple_reg (ssa_name (i)))
+{
+	tree old_name = ssa_name (i);
+	tree new_name = get_new_name_from_old_name (rename_map, old_name);
+	register_old_and_new_names (SCOP_LIVEOUT_RENAMES (scop),
+				    old_name, new_name);
+}
+}
+/* Copies BB and includes in the copied BB all the statements that can
+be reached following the use-def chains from the memory accesses,
+and returns the next edge following this new block.  */
+static edge
+copy_bb_and_scalar_dependences (basic_block bb, scop_p scop,
+				edge next_e, htab_t map)
+{
+basic_block new_bb = split_edge (next_e);
+next_e = single_succ_edge (new_bb);
+graphite_copy_stmts_from_block (bb, new_bb, map);
+remove_condition (new_bb);
+rename_variables (new_bb, map);
+remove_phi_nodes (new_bb);
+expand_scalar_variables (new_bb, scop, map);
+register_scop_liveout_renames (scop, map);
+return next_e;
+}
+/* Helper function for htab_traverse in insert_loop_close_phis.  */
+static int
+add_loop_exit_phis (void **slot, void *s)
+{
+struct rename_map_elt *entry = (struct rename_map_elt *) *slot;
+tree new_name = entry->new_name;
+basic_block bb = (basic_block) s;
+gimple phi = create_phi_node (new_name, bb);
+tree res = create_new_def_for (gimple_phi_result (phi), phi,
+				 gimple_phi_result_ptr (phi));
+add_phi_arg (phi, new_name, single_pred_edge (bb));
+entry->new_name = res;
+*slot = entry;
+return 1;
+}
+/* Iterate over the SCOP_LIVEOUT_RENAMES (SCOP) and get tuples of the
+form (OLD_NAME, NEW_NAME).  Insert in BB "RES = phi (NEW_NAME)",
+and finally register in SCOP_LIVEOUT_RENAMES (scop) the tuple
+(OLD_NAME, RES).  */
+static void
+insert_loop_close_phis (scop_p scop, basic_block bb)
+{
+update_ssa (TODO_update_ssa);
+htab_traverse (SCOP_LIVEOUT_RENAMES (scop), add_loop_exit_phis, bb);
+update_ssa (TODO_update_ssa);
+}
+/* Helper structure for htab_traverse in insert_guard_phis.  */
+struct igp {
+basic_block bb;
+edge true_edge, false_edge;
+htab_t liveout_before_guard;
+};
+/* Return the default name that is before the guard.  */
+static tree
+default_liveout_before_guard (htab_t liveout_before_guard, tree old_name)
+{
+tree res = get_new_name_from_old_name (liveout_before_guard, old_name);
+if (res == old_name)
+{
+if (is_gimple_reg (res))
+	return fold_convert (TREE_TYPE (res), integer_zero_node);
+return gimple_default_def (cfun, res);
+}
+return res;
+}
+/* Helper function for htab_traverse in insert_guard_phis.  */
+static int
+add_guard_exit_phis (void **slot, void *s)
+{
+struct rename_map_elt *entry = (struct rename_map_elt *) *slot;
+struct igp *i = (struct igp *) s;
+basic_block bb = i->bb;
+edge true_edge = i->true_edge;
+edge false_edge = i->false_edge;
+tree name1 = entry->new_name;
+tree name2 = default_liveout_before_guard (i->liveout_before_guard,
+					     entry->old_name);
+gimple phi = create_phi_node (name1, bb);
+tree res = create_new_def_for (gimple_phi_result (phi), phi,
+				 gimple_phi_result_ptr (phi));
+add_phi_arg (phi, name1, true_edge);
+add_phi_arg (phi, name2, false_edge);
+entry->new_name = res;
+*slot = entry;
+return 1;
+}
+/* Iterate over the SCOP_LIVEOUT_RENAMES (SCOP) and get tuples of the
+form (OLD_NAME, NAME1).  If there is a correspondent tuple of
+OLD_NAME in LIVEOUT_BEFORE_GUARD, i.e. (OLD_NAME, NAME2) then
+insert in BB
+| RES = phi (NAME1 (on TRUE_EDGE), NAME2 (on FALSE_EDGE))"
+if there is no tuple for OLD_NAME in LIVEOUT_BEFORE_GUARD, insert
+| RES = phi (NAME1 (on TRUE_EDGE),
+|            DEFAULT_DEFINITION of NAME1 (on FALSE_EDGE))".
+Finally register in SCOP_LIVEOUT_RENAMES (scop) the tuple
+(OLD_NAME, RES).  */
+static void
+insert_guard_phis (scop_p scop, basic_block bb, edge true_edge,
+		   edge false_edge, htab_t liveout_before_guard)
+{
+struct igp i;
+i.bb = bb;
+i.true_edge = true_edge;
+i.false_edge = false_edge;
+i.liveout_before_guard = liveout_before_guard;
+update_ssa (TODO_update_ssa);
+htab_traverse (SCOP_LIVEOUT_RENAMES (scop), add_guard_exit_phis, &i);
+update_ssa (TODO_update_ssa);
+}
+/* Helper function for htab_traverse.  */
+static int
+copy_renames (void **slot, void *s)
+{
+struct rename_map_elt *entry = (struct rename_map_elt *) *slot;
+htab_t res = (htab_t) s;
+tree old_name = entry->old_name;
+tree new_name = entry->new_name;
+struct rename_map_elt tmp;
+PTR *x;
+tmp.old_name = old_name;
+x = htab_find_slot (res, &tmp, INSERT);
+if (!*x)
+*x = new_rename_map_elt (old_name, new_name);
+return 1;
+}
+/* Translates a CLAST statement STMT to GCC representation in the
+context of a SCOP.
+- NEXT_E is the edge where new generated code should be attached.
+- CONTEXT_LOOP is the loop in which the generated code will be placed
+(might be NULL).
+- IVSTACK contains the surrounding loops around the statement to be
+translated.
+*/
+static edge
+translate_clast (scop_p scop, struct loop *context_loop,
+		 struct clast_stmt *stmt, edge next_e, loop_iv_stack ivstack)
+{
+if (!stmt)
+return next_e;
+if (CLAST_STMT_IS_A (stmt, stmt_root))
+return translate_clast (scop, context_loop, stmt->next, next_e, ivstack);
+if (CLAST_STMT_IS_A (stmt, stmt_user))
+{
+htab_t map;
+CloogStatement *cs = ((struct clast_user_stmt *) stmt)->statement;
+graphite_bb_p gbb = (graphite_bb_p) cloog_statement_usr (cs);
+if (GBB_BB (gbb) == ENTRY_BLOCK_PTR)
+	return next_e;
+map = htab_create (10, rename_map_elt_info, eq_rename_map_elts, free);
+loop_iv_stack_patch_for_consts (ivstack, (struct clast_user_stmt *) stmt);
+build_iv_mapping (ivstack, map, gbb, scop);
+next_e = copy_bb_and_scalar_dependences (GBB_BB (gbb), scop,
+					       next_e, map);
+htab_delete (map);
+loop_iv_stack_remove_constants (ivstack);
+update_ssa (TODO_update_ssa);
+recompute_all_dominators ();
+graphite_verify ();
+return translate_clast (scop, context_loop, stmt->next, next_e, ivstack);
+}
+if (CLAST_STMT_IS_A (stmt, stmt_for))
+{
+struct loop *loop
+	= graphite_create_new_loop (scop, next_e, (struct clast_for *) stmt,
+				    ivstack, context_loop ? context_loop
+				    : get_loop (0));
+edge last_e = single_exit (loop);
+next_e = translate_clast (scop, loop, ((struct clast_for *) stmt)->body,
+				single_pred_edge (loop->latch), ivstack);
+redirect_edge_succ_nodup (next_e, loop->latch);
+set_immediate_dominator (CDI_DOMINATORS, next_e->dest, next_e->src);
+loop_iv_stack_pop (ivstack);
+last_e = single_succ_edge (split_edge (last_e));
+insert_loop_close_phis (scop, last_e->src);
+recompute_all_dominators ();
+graphite_verify ();
+return translate_clast (scop, context_loop, stmt->next, last_e, ivstack);
+}
+if (CLAST_STMT_IS_A (stmt, stmt_guard))
+{
+htab_t liveout_before_guard = htab_create (10, rename_map_elt_info,
+						 eq_rename_map_elts, free);
+edge last_e = graphite_create_new_guard (scop, next_e,
+					       ((struct clast_guard *) stmt),
+					       ivstack);
+edge true_e = get_true_edge_from_guard_bb (next_e->dest);
+edge false_e = get_false_edge_from_guard_bb (next_e->dest);
+edge exit_true_e = single_succ_edge (true_e->dest);
+edge exit_false_e = single_succ_edge (false_e->dest);
+htab_traverse (SCOP_LIVEOUT_RENAMES (scop), copy_renames,
+		     liveout_before_guard);
+next_e = translate_clast (scop, context_loop,
+				((struct clast_guard *) stmt)->then,
+				true_e, ivstack);
+insert_guard_phis (scop, last_e->src, exit_true_e, exit_false_e,
+			 liveout_before_guard);
+htab_delete (liveout_before_guard);
+recompute_all_dominators ();
+graphite_verify ();
+return translate_clast (scop, context_loop, stmt->next, last_e, ivstack);
+}
+if (CLAST_STMT_IS_A (stmt, stmt_block))
+{
+next_e = translate_clast (scop, context_loop,
+				((struct clast_block *) stmt)->body,
+				next_e, ivstack);
+recompute_all_dominators ();
+graphite_verify ();
+return translate_clast (scop, context_loop, stmt->next, next_e, ivstack);
+}
+gcc_unreachable ();
+}
+/* Free the SCATTERING domain list.  */
+static void
+free_scattering (CloogDomainList *scattering)
+{
+while (scattering)
+{
+CloogDomain *dom = cloog_domain (scattering);
+CloogDomainList *next = cloog_next_domain (scattering);
+cloog_domain_free (dom);
+free (scattering);
+scattering = next;
+}
+}
+/* Build cloog program for SCoP.  */
+static void
+build_cloog_prog (scop_p scop)
+{
+int i;
+int max_nb_loops = scop_max_loop_depth (scop);
+graphite_bb_p gbb;
+CloogLoop *loop_list = NULL;
+CloogBlockList *block_list = NULL;
+CloogDomainList *scattering = NULL;
+CloogProgram *prog = SCOP_PROG (scop);
+int nbs = 2 * max_nb_loops + 1;
+int *scaldims = (int *) xmalloc (nbs * (sizeof (int)));
+cloog_program_set_nb_scattdims (prog, nbs);
+initialize_cloog_names (scop);
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gbb); i++)
+{
+/* Build new block.  */
+CloogMatrix *domain = GBB_DOMAIN (gbb);
+CloogStatement *stmt = cloog_statement_alloc (GBB_BB (gbb)->index);
+CloogBlock *block = cloog_block_alloc (stmt, 0, NULL,
+					     nb_loops_around_gb (gbb));
+cloog_statement_set_usr (stmt, gbb);
+/* Add empty domain to all bbs, which do not yet have a domain, as they
+are not part of any loop.  */
+if (domain == NULL)
+	{
+domain = cloog_matrix_alloc (0, scop_nb_params (scop) + 2);
+GBB_DOMAIN (gbb) = domain;
+	}
+/* Build loop list.  */
+{
+CloogLoop *new_loop_list = cloog_loop_malloc ();
+cloog_loop_set_next (new_loop_list, loop_list);
+cloog_loop_set_domain (new_loop_list,
+			       cloog_domain_matrix2domain (domain));
+cloog_loop_set_block (new_loop_list, block);
+loop_list = new_loop_list;
+}
+/* Build block list.  */
+{
+CloogBlockList *new_block_list = cloog_block_list_malloc ();
+cloog_block_list_set_next (new_block_list, block_list);
+cloog_block_list_set_block (new_block_list, block);
+block_list = new_block_list;
+}
+/* Build scattering list.  */
+{
+/* XXX: Replace with cloog_domain_list_alloc(), when available.  */
+CloogDomainList *new_scattering
+	  = (CloogDomainList *) xmalloc (sizeof (CloogDomainList));
+CloogMatrix *scat_mat = schedule_to_scattering (gbb, nbs);
+cloog_set_next_domain (new_scattering, scattering);
+cloog_set_domain (new_scattering,
+			  cloog_domain_matrix2domain (scat_mat));
+scattering = new_scattering;
+cloog_matrix_free (scat_mat);
+}
+}
+cloog_program_set_loop (prog, loop_list);
+cloog_program_set_blocklist (prog, block_list);
+for (i = 0; i < nbs; i++)
+scaldims[i] = 0 ;
+cloog_program_set_scaldims (prog, scaldims);
+/* Extract scalar dimensions to simplify the code generation problem.  */
+cloog_program_extract_scalars (prog, scattering);
+/* Apply scattering.  */
+cloog_program_scatter (prog, scattering);
+free_scattering (scattering);
+/* Iterators corresponding to scalar dimensions have to be extracted.  */
+cloog_names_scalarize (cloog_program_names (prog), nbs,
+			 cloog_program_scaldims (prog));
+/* Free blocklist.  */
+{
+CloogBlockList *next = cloog_program_blocklist (prog);
+while (next)
+{
+CloogBlockList *toDelete = next;
+next = cloog_block_list_next (next);
+cloog_block_list_set_next (toDelete, NULL);
+cloog_block_list_set_block (toDelete, NULL);
+cloog_block_list_free (toDelete);
+}
+cloog_program_set_blocklist (prog, NULL);
+}
+}
+/* Return the options that will be used in GLOOG.  */
+static CloogOptions *
+set_cloog_options (void)
+{
+CloogOptions *options = cloog_options_malloc ();
+/* Change cloog output language to C.  If we do use FORTRAN instead, cloog
+will stop e.g. with "ERROR: unbounded loops not allowed in FORTRAN.", if
+we pass an incomplete program to cloog.  */
+options->language = LANGUAGE_C;
+/* Enable complex equality spreading: removes dummy statements
+(assignments) in the generated code which repeats the
+substitution equations for statements.  This is useless for
+GLooG.  */
+options->esp = 1;
+/* Enable C pretty-printing mode: normalizes the substitution
+equations for statements.  */
+options->cpp = 1;
+/* Allow cloog to build strides with a stride width different to one.
+This example has stride = 4:
+for (i = 0; i < 20; i += 4)
+A  */
+options->strides = 1;
+/* Disable optimizations and make cloog generate source code closer to the
+input.  This is useful for debugging,  but later we want the optimized
+code.
+XXX: We can not disable optimizations, as loop blocking is not working
+without them.  */
+if (0)
+{
+options->f = -1;
+options->l = INT_MAX;
+}
+return options;
+}
+/* Prints STMT to STDERR.  */
+void
+debug_clast_stmt (struct clast_stmt *stmt)
+{
+CloogOptions *options = set_cloog_options ();
+pprint (stderr, stmt, 0, options);
+}
+/* Find the right transform for the SCOP, and return a Cloog AST
+representing the new form of the program.  */
+static struct clast_stmt *
+find_transform (scop_p scop)
+{
+struct clast_stmt *stmt;
+CloogOptions *options = set_cloog_options ();
+/* Connect new cloog prog generation to graphite.  */
+build_cloog_prog (scop);
+if (dump_file && (dump_flags & TDF_DETAILS))
+{
+fprintf (dump_file, "Cloog Input [\n");
+cloog_program_print (dump_file, SCOP_PROG(scop));
+fprintf (dump_file, "]\n");
+}
+SCOP_PROG (scop) = cloog_program_generate (SCOP_PROG (scop), options);
+stmt = cloog_clast_create (SCOP_PROG (scop), options);
+if (dump_file && (dump_flags & TDF_DETAILS))
+{
+fprintf (dump_file, "Cloog Output[\n");
+pprint (dump_file, stmt, 0, options);
+cloog_program_dump_cloog (dump_file, SCOP_PROG (scop));
+fprintf (dump_file, "]\n");
+}
+cloog_options_free (options);
+return stmt;
+}
+/* Remove from the CFG the REGION.  */
+static inline void
+remove_sese_region (sese region)
+{
+VEC (basic_block, heap) *bbs = NULL;
+basic_block entry_bb = SESE_ENTRY (region)->dest;
+basic_block exit_bb = SESE_EXIT (region)->dest;
+basic_block bb;
+int i;
+VEC_safe_push (basic_block, heap, bbs, entry_bb);
+gather_blocks_in_sese_region (entry_bb, exit_bb, &bbs);
+for (i = 0; VEC_iterate (basic_block, bbs, i, bb); i++)
+delete_basic_block (bb);
+VEC_free (basic_block, heap, bbs);
+}
+typedef struct ifsese {
+sese region;
+sese true_region;
+sese false_region;
+} *ifsese;
+static inline edge
+if_region_entry (ifsese if_region)
+{
+return SESE_ENTRY (if_region->region);
+}
+static inline edge
+if_region_exit (ifsese if_region)
+{
+return SESE_EXIT (if_region->region);
+}
+static inline basic_block
+if_region_get_condition_block (ifsese if_region)
+{
+return if_region_entry (if_region)->dest;
+}
+static inline void
+if_region_set_false_region (ifsese if_region, sese region)
+{
+basic_block condition = if_region_get_condition_block (if_region);
+edge false_edge = get_false_edge_from_guard_bb (condition);
+basic_block dummy = false_edge->dest;
+edge entry_region = SESE_ENTRY (region);
+edge exit_region = SESE_EXIT (region);
+basic_block before_region = entry_region->src;
+basic_block last_in_region = exit_region->src;
+void **slot = htab_find_slot_with_hash (current_loops->exits, exit_region,
+					  htab_hash_pointer (exit_region),
+					  NO_INSERT);
+entry_region->flags = false_edge->flags;
+false_edge->flags = exit_region->flags;
+redirect_edge_pred (entry_region, condition);
+redirect_edge_pred (exit_region, before_region);
+redirect_edge_pred (false_edge, last_in_region);
+redirect_edge_succ (false_edge, single_succ (dummy));
+delete_basic_block (dummy);
+exit_region->flags = EDGE_FALLTHRU;
+recompute_all_dominators ();
+SESE_EXIT (region) = false_edge;
+if_region->false_region = region;
+if (slot)
+{
+struct loop_exit *loop_exit = GGC_CNEW (struct loop_exit);
+memcpy (loop_exit, *((struct loop_exit **) slot), sizeof (struct loop_exit));
+htab_clear_slot (current_loops->exits, slot);
+slot = htab_find_slot_with_hash (current_loops->exits, false_edge,
+				       htab_hash_pointer (false_edge),
+				       INSERT);
+loop_exit->e = false_edge;
+*slot = loop_exit;
+false_edge->src->loop_father->exits->next = loop_exit;
+}
+}
+static ifsese
+create_if_region_on_edge (edge entry, tree condition)
+{
+edge e;
+edge_iterator ei;
+sese sese_region = GGC_NEW (struct sese);
+sese true_region = GGC_NEW (struct sese);
+sese false_region = GGC_NEW (struct sese);
+ifsese if_region = GGC_NEW (struct ifsese);
+edge exit = create_empty_if_region_on_edge (entry, condition);
+if_region->region = sese_region;
+if_region->region->entry = entry;
+if_region->region->exit = exit;
+FOR_EACH_EDGE (e, ei, entry->dest->succs)
+{
+if (e->flags & EDGE_TRUE_VALUE)
+	{
+	  true_region->entry = e;
+	  true_region->exit = single_succ_edge (e->dest);
+	  if_region->true_region = true_region;
+	}
+else if (e->flags & EDGE_FALSE_VALUE)
+	{
+	  false_region->entry = e;
+	  false_region->exit = single_succ_edge (e->dest);
+	  if_region->false_region = false_region;
+	}
+}
+return if_region;
+}
+/* Moves REGION in a condition expression:
+| if (1)
+|   ;
+| else
+|   REGION;
+*/
+static ifsese
+move_sese_in_condition (sese region)
+{
+basic_block pred_block = split_edge (SESE_ENTRY (region));
+ifsese if_region = NULL;
+SESE_ENTRY (region) = single_succ_edge (pred_block);
+if_region = create_if_region_on_edge (single_pred_edge (pred_block), integer_one_node);
+if_region_set_false_region (if_region, region);
+return if_region;
+}
+/* Add exit phis for USE on EXIT.  */
+static void
+scop_add_exit_phis_edge (basic_block exit, tree use, edge false_e, edge true_e)
+{
+gimple phi = create_phi_node (use, exit);
+create_new_def_for (gimple_phi_result (phi), phi,
+		      gimple_phi_result_ptr (phi));
+add_phi_arg (phi, use, false_e);
+add_phi_arg (phi, use, true_e);
+}
+/* Add phi nodes for VAR that is used in LIVEIN.  Phi nodes are
+inserted in block BB.  */
+static void
+scop_add_exit_phis_var (basic_block bb, tree var, bitmap livein,
+			edge false_e, edge true_e)
+{
+bitmap def;
+basic_block def_bb = gimple_bb (SSA_NAME_DEF_STMT (var));
+if (is_gimple_reg (var))
+bitmap_clear_bit (livein, def_bb->index);
+else
+bitmap_set_bit (livein, def_bb->index);
+def = BITMAP_ALLOC (NULL);
+bitmap_set_bit (def, def_bb->index);
+compute_global_livein (livein, def);
+BITMAP_FREE (def);
+scop_add_exit_phis_edge (bb, var, false_e, true_e);
+}
+/* Insert in the block BB phi nodes for variables defined in REGION
+and used outside the REGION.  The code generation moves REGION in
+the else clause of an "if (1)" and generates code in the then
+clause that is at this point empty:
+| if (1)
+|   empty;
+| else
+|   REGION;
+*/
+static void
+scop_insert_phis_for_liveouts (sese region, basic_block bb,
+			       edge false_e, edge true_e)
+{
+unsigned i;
+bitmap_iterator bi;
+update_ssa (TODO_update_ssa);
+EXECUTE_IF_SET_IN_BITMAP (SESE_LIVEOUT (region), 0, i, bi)
+scop_add_exit_phis_var (bb, ssa_name (i), SESE_LIVEIN_VER (region, i),
+			    false_e, true_e);
+update_ssa (TODO_update_ssa);
+}
+/* Get the definition of NAME before the SCOP.  Keep track of the
+basic blocks that have been VISITED in a bitmap.  */
+static tree
+get_vdef_before_scop (scop_p scop, tree name, sbitmap visited)
+{
+unsigned i;
+gimple def_stmt = SSA_NAME_DEF_STMT (name);
+basic_block def_bb = gimple_bb (def_stmt);
+if (!def_bb
+|| !bb_in_sese_p (def_bb, SCOP_REGION (scop)))
+return name;
+if (TEST_BIT (visited, def_bb->index))
+return NULL_TREE;
+SET_BIT (visited, def_bb->index);
+switch (gimple_code (def_stmt))
+{
+case GIMPLE_PHI:
+for (i = 0; i < gimple_phi_num_args (def_stmt); i++)
+	{
+	  tree arg = gimple_phi_arg_def (def_stmt, i);
+	  tree res = get_vdef_before_scop (scop, arg, visited);
+	  if (res)
+	    return res;
+	}
+return NULL_TREE;
+default:
+return NULL_TREE;
+}
+}
+/* Adjust a virtual phi node PHI that is placed at the end of the
+generated code for SCOP:
+| if (1)
+|   generated code from REGION;
+| else
+|   REGION;
+The FALSE_E edge comes from the original code, TRUE_E edge comes
+from the code generated for the SCOP.  */
+static void
+scop_adjust_vphi (scop_p scop, gimple phi, edge true_e)
+{
+unsigned i;
+gcc_assert (gimple_phi_num_args (phi) == 2);
+for (i = 0; i < gimple_phi_num_args (phi); i++)
+if (gimple_phi_arg_edge (phi, i) == true_e)
+{
+	tree true_arg, false_arg, before_scop_arg;
+	sbitmap visited;
+	true_arg = gimple_phi_arg_def (phi, i);
+	if (!SSA_NAME_IS_DEFAULT_DEF (true_arg))
+	  return;
+	false_arg = gimple_phi_arg_def (phi, i == 0 ? 1 : 0);
+	if (SSA_NAME_IS_DEFAULT_DEF (false_arg))
+	  return;
+	visited = sbitmap_alloc (last_basic_block);
+	sbitmap_zero (visited);
+	before_scop_arg = get_vdef_before_scop (scop, false_arg, visited);
+	gcc_assert (before_scop_arg != NULL_TREE);
+	SET_PHI_ARG_DEF (phi, i, before_scop_arg);
+	sbitmap_free (visited);
+}
+}
+/* Adjusts the phi nodes in the block BB for variables defined in
+SCOP_REGION and used outside the SCOP_REGION.  The code generation
+moves SCOP_REGION in the else clause of an "if (1)" and generates
+code in the then clause:
+| if (1)
+|   generated code from REGION;
+| else
+|   REGION;
+To adjust the phi nodes after the condition, SCOP_LIVEOUT_RENAMES
+hash table is used: this stores for a name that is part of the
+LIVEOUT of SCOP_REGION its new name in the generated code.  */
+static void
+scop_adjust_phis_for_liveouts (scop_p scop, basic_block bb, edge false_e,
+			       edge true_e)
+{
+gimple_stmt_iterator si;
+for (si = gsi_start_phis (bb); !gsi_end_p (si); gsi_next (&si))
+{
+unsigned i;
+unsigned false_i = 0;
+gimple phi = gsi_stmt (si);
+if (!is_gimple_reg (PHI_RESULT (phi)))
+	{
+	  scop_adjust_vphi (scop, phi, true_e);
+	  continue;
+	}
+for (i = 0; i < gimple_phi_num_args (phi); i++)
+	if (gimple_phi_arg_edge (phi, i) == false_e)
+	  {
+	    false_i = i;
+	    break;
+	  }
+for (i = 0; i < gimple_phi_num_args (phi); i++)
+	if (gimple_phi_arg_edge (phi, i) == true_e)
+	  {
+	    tree old_name = gimple_phi_arg_def (phi, false_i);
+	    tree new_name = get_new_name_from_old_name
+	      (SCOP_LIVEOUT_RENAMES (scop), old_name);
+	    gcc_assert (old_name != new_name);
+	    SET_PHI_ARG_DEF (phi, i, new_name);
+	  }
+}
+}
+/* Returns the first cloog name used in EXPR.  */
+static const char *
+find_cloog_iv_in_expr (struct clast_expr *expr)
+{
+struct clast_term *term = (struct clast_term *) expr;
+if (expr->type == expr_term
+&& !term->var)
+return NULL;
+if (expr->type == expr_term)
+return term->var;
+if (expr->type == expr_red)
+{
+int i;
+struct clast_reduction *red = (struct clast_reduction *) expr;
+for (i = 0; i < red->n; i++)
+	{
+	  const char *res = find_cloog_iv_in_expr ((red)->elts[i]);
+	  if (res)
+	    return res;
+	}
+}
+return NULL;
+}
+/* Build for a clast_user_stmt USER_STMT a map between the CLAST
+induction variables and the corresponding GCC old induction
+variables.  This information is stored on each GRAPHITE_BB.  */
+static void
+compute_cloog_iv_types_1 (graphite_bb_p gbb,
+			  struct clast_user_stmt *user_stmt)
+{
+struct clast_stmt *t;
+int index = 0;
+for (t = user_stmt->substitutions; t; t = t->next, index++)
+{
+PTR *slot;
+struct ivtype_map_elt tmp;
+struct clast_expr *expr = (struct clast_expr *)
+	((struct clast_assignment *)t)->RHS;
+/* Create an entry (clast_var, type).  */
+tmp.cloog_iv = find_cloog_iv_in_expr (expr);
+if (!tmp.cloog_iv)
+	continue;
+slot = htab_find_slot (GBB_CLOOG_IV_TYPES (gbb), &tmp, INSERT);
+if (!*slot)
+	{
+	  loop_p loop = gbb_loop_at_index (gbb, index);
+	  tree oldiv = oldiv_for_loop (GBB_SCOP (gbb), loop);
+	  tree type = oldiv ? TREE_TYPE (oldiv) : integer_type_node;
+	  *slot = new_ivtype_map_elt (tmp.cloog_iv, type);
+	}
+}
+}
+/* Walk the CLAST tree starting from STMT and build for each
+clast_user_stmt a map between the CLAST induction variables and the
+corresponding GCC old induction variables.  This information is
+stored on each GRAPHITE_BB.  */
+static void
+compute_cloog_iv_types (struct clast_stmt *stmt)
+{
+if (!stmt)
+return;
+if (CLAST_STMT_IS_A (stmt, stmt_root))
+goto next;
+if (CLAST_STMT_IS_A (stmt, stmt_user))
+{
+CloogStatement *cs = ((struct clast_user_stmt *) stmt)->statement;
+graphite_bb_p gbb = (graphite_bb_p) cloog_statement_usr (cs);
+GBB_CLOOG_IV_TYPES (gbb) = htab_create (10, ivtype_map_elt_info,
+					      eq_ivtype_map_elts, free);
+compute_cloog_iv_types_1 (gbb, (struct clast_user_stmt *) stmt);
+goto next;
+}
+if (CLAST_STMT_IS_A (stmt, stmt_for))
+{
+struct clast_stmt *s = ((struct clast_for *) stmt)->body;
+compute_cloog_iv_types (s);
+goto next;
+}
+if (CLAST_STMT_IS_A (stmt, stmt_guard))
+{
+struct clast_stmt *s = ((struct clast_guard *) stmt)->then;
+compute_cloog_iv_types (s);
+goto next;
+}
+if (CLAST_STMT_IS_A (stmt, stmt_block))
+{
+struct clast_stmt *s = ((struct clast_block *) stmt)->body;
+compute_cloog_iv_types (s);
+goto next;
+}
+gcc_unreachable ();
+next:
+compute_cloog_iv_types (stmt->next);
+}
+/* GIMPLE Loop Generator: generates loops from STMT in GIMPLE form for
+the given SCOP.  Return true if code generation succeeded.  */
+static bool
+gloog (scop_p scop, struct clast_stmt *stmt)
+{
+edge new_scop_exit_edge = NULL;
+VEC (iv_stack_entry_p, heap) *ivstack = VEC_alloc (iv_stack_entry_p, heap,
+						     10);
+loop_p context_loop;
+ifsese if_region = NULL;
+recompute_all_dominators ();
+graphite_verify ();
+if_region = move_sese_in_condition (SCOP_REGION (scop));
+sese_build_livein_liveouts (SCOP_REGION (scop));
+scop_insert_phis_for_liveouts (SCOP_REGION (scop),
+				 if_region->region->exit->src,
+				 if_region->false_region->exit,
+				 if_region->true_region->exit);
+recompute_all_dominators ();
+graphite_verify ();
+context_loop = SESE_ENTRY (SCOP_REGION (scop))->src->loop_father;
+compute_cloog_iv_types (stmt);
+new_scop_exit_edge = translate_clast (scop, context_loop, stmt,
+					if_region->true_region->entry,
+					&ivstack);
+free_loop_iv_stack (&ivstack);
+cloog_clast_free (stmt);
+graphite_verify ();
+scop_adjust_phis_for_liveouts (scop,
+				 if_region->region->exit->src,
+				 if_region->false_region->exit,
+				 if_region->true_region->exit);
+recompute_all_dominators ();
+graphite_verify ();
+return true;
+}
+/* Returns the number of data references in SCOP.  */
+static int
+nb_data_refs_in_scop (scop_p scop)
+{
+int i;
+graphite_bb_p gbb;
+int res = 0;
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gbb); i++)
+res += VEC_length (data_reference_p, GBB_DATA_REFS (gbb));
+return res;
+}
+/* Move the loop at index LOOP and insert it before index NEW_LOOP_POS.
+This transformartion is only valid, if the loop nest between i and k is
+perfectly nested. Therefore we do not need to change the static schedule.
+Example:
+for (i = 0; i < 50; i++)
+for (j ...)
+for (k = 5; k < 100; k++)
+A
+To move k before i use:
+graphite_trans_bb_move_loop (A, 2, 0)
+for (k = 5; k < 100; k++)
+for (i = 0; i < 50; i++)
+for (j ...)
+A
+And to move k back:
+graphite_trans_bb_move_loop (A, 0, 2)
+This function does not check the validity of interchanging loops.
+This should be checked before calling this function.  */
+static void
+graphite_trans_bb_move_loop (graphite_bb_p gb, int loop,
+			     int new_loop_pos)
+{
+CloogMatrix *domain = GBB_DOMAIN (gb);
+int row, j;
+loop_p tmp_loop_p;
+gcc_assert (loop < gbb_nb_loops (gb)
+	      && new_loop_pos < gbb_nb_loops (gb));
+/* Update LOOPS vector.  */
+tmp_loop_p = VEC_index (loop_p, GBB_LOOPS (gb), loop);
+VEC_ordered_remove (loop_p, GBB_LOOPS (gb), loop);
+VEC_safe_insert (loop_p, heap, GBB_LOOPS (gb), new_loop_pos, tmp_loop_p);
+/* Move the domain columns.  */
+if (loop < new_loop_pos)
+for (row = 0; row < domain->NbRows; row++)
+{
+Value tmp;
+value_init (tmp);
+value_assign (tmp, domain->p[row][loop + 1]);
+for (j = loop ; j < new_loop_pos - 1; j++)
+value_assign (domain->p[row][j + 1], domain->p[row][j + 2]);
+value_assign (domain->p[row][new_loop_pos], tmp);
+value_clear (tmp);
+}
+else
+for (row = 0; row < domain->NbRows; row++)
+{
+Value tmp;
+value_init (tmp);
+value_assign (tmp, domain->p[row][loop + 1]);
+for (j = loop ; j > new_loop_pos; j--)
+value_assign (domain->p[row][j + 1], domain->p[row][j]);
+value_assign (domain->p[row][new_loop_pos + 1], tmp);
+value_clear (tmp);
+}
+}
+/* Get the index of the column representing constants in the DOMAIN
+matrix.  */
+static int
+const_column_index (CloogMatrix *domain)
+{
+return domain->NbColumns - 1;
+}
+/* Get the first index that is positive or negative, determined
+following the value of POSITIVE, in matrix DOMAIN in COLUMN.  */
+static int
+get_first_matching_sign_row_index (CloogMatrix *domain, int column,
+				   bool positive)
+{
+int row;
+for (row = 0; row < domain->NbRows; row++)
+{
+int val = value_get_si (domain->p[row][column]);
+if (val > 0 && positive)
+	return row;
+else if (val < 0 && !positive)
+	return row;
+}
+gcc_unreachable ();
+}
+/* Get the lower bound of COLUMN in matrix DOMAIN.  */
+static int
+get_lower_bound_row (CloogMatrix *domain, int column)
+{
+return get_first_matching_sign_row_index (domain, column, true);
+}
+/* Get the upper bound of COLUMN in matrix DOMAIN.  */
+static int
+get_upper_bound_row (CloogMatrix *domain, int column)
+{
+return get_first_matching_sign_row_index (domain, column, false);
+}
+/* Copies the OLD_ROW constraint from OLD_DOMAIN to the NEW_DOMAIN at
+row NEW_ROW.  */
+static void
+copy_constraint (CloogMatrix *old_domain, CloogMatrix *new_domain,
+		 int old_row, int new_row)
+{
+int i;
+gcc_assert (old_domain->NbColumns == new_domain->NbColumns
+	      && old_row < old_domain->NbRows
+	      && new_row < new_domain->NbRows);
+for (i = 0; i < old_domain->NbColumns; i++)
+value_assign (new_domain->p[new_row][i], old_domain->p[old_row][i]);
+}
+/* Swap coefficients of variables X and Y on row R.   */
+static void
+swap_constraint_variables (CloogMatrix *domain,
+			   int r, int x, int y)
+{
+value_swap (domain->p[r][x], domain->p[r][y]);
+}
+/* Scale by X the coefficient C of constraint at row R in DOMAIN.  */
+static void
+scale_constraint_variable (CloogMatrix *domain,
+			   int r, int c, int x)
+{
+Value strip_size_value;
+value_init (strip_size_value);
+value_set_si (strip_size_value, x);
+value_multiply (domain->p[r][c], domain->p[r][c], strip_size_value);
+value_clear (strip_size_value);
+}
+/* Strip mines the loop of BB at the position LOOP_DEPTH with STRIDE.
+Always valid, but not always a performance improvement.  */
+static void
+graphite_trans_bb_strip_mine (graphite_bb_p gb, int loop_depth, int stride)
+{
+int row, col;
+CloogMatrix *domain = GBB_DOMAIN (gb);
+CloogMatrix *new_domain = cloog_matrix_alloc (domain->NbRows + 3,
+domain->NbColumns + 1);
+int col_loop_old = loop_depth + 2;
+int col_loop_strip = col_loop_old - 1;
+gcc_assert (loop_depth <= gbb_nb_loops (gb) - 1);
+VEC_safe_insert (loop_p, heap, GBB_LOOPS (gb), loop_depth, NULL);
+GBB_DOMAIN (gb) = new_domain;
+for (row = 0; row < domain->NbRows; row++)
+for (col = 0; col < domain->NbColumns; col++)
+if (col <= loop_depth)
+	value_assign (new_domain->p[row][col], domain->p[row][col]);
+else
+	value_assign (new_domain->p[row][col + 1], domain->p[row][col]);
+row = domain->NbRows;
+/* Lower bound of the outer stripped loop.  */
+copy_constraint (new_domain, new_domain,
+		   get_lower_bound_row (new_domain, col_loop_old), row);
+swap_constraint_variables (new_domain, row, col_loop_old, col_loop_strip);
+row++;
+/* Upper bound of the outer stripped loop.  */
+copy_constraint (new_domain, new_domain,
+		   get_upper_bound_row (new_domain, col_loop_old), row);
+swap_constraint_variables (new_domain, row, col_loop_old, col_loop_strip);
+scale_constraint_variable (new_domain, row, col_loop_strip, stride);
+row++;
+/* Lower bound of a tile starts at "stride * outer_iv".  */
+row = get_lower_bound_row (new_domain, col_loop_old);
+value_set_si (new_domain->p[row][0], 1);
+value_set_si (new_domain->p[row][const_column_index (new_domain)], 0);
+value_set_si (new_domain->p[row][col_loop_old], 1);
+value_set_si (new_domain->p[row][col_loop_strip], -1 * stride);
+/* Upper bound of a tile stops at "stride * outer_iv + stride - 1",
+or at the old upper bound that is not modified.  */
+row = new_domain->NbRows - 1;
+value_set_si (new_domain->p[row][0], 1);
+value_set_si (new_domain->p[row][col_loop_old], -1);
+value_set_si (new_domain->p[row][col_loop_strip], stride);
+value_set_si (new_domain->p[row][const_column_index (new_domain)],
+		stride - 1);
+cloog_matrix_free (domain);
+/* Update static schedule.  */
+{
+int i;
+int nb_loops = gbb_nb_loops (gb);
+lambda_vector new_schedule = lambda_vector_new (nb_loops + 1);
+for (i = 0; i <= loop_depth; i++)
+new_schedule[i] = GBB_STATIC_SCHEDULE (gb)[i];
+for (i = loop_depth + 1; i <= nb_loops - 2; i++)
+new_schedule[i + 2] = GBB_STATIC_SCHEDULE (gb)[i];
+GBB_STATIC_SCHEDULE (gb) = new_schedule;
+}
+}
+/* Returns true when the strip mining of LOOP_INDEX by STRIDE is
+profitable or undecidable.  GB is the statement around which the
+loops will be strip mined.  */
+static bool
+strip_mine_profitable_p (graphite_bb_p gb, int stride,
+			 int loop_index)
+{
+bool res = true;
+edge exit = NULL;
+tree niter;
+loop_p loop;
+long niter_val;
+loop = VEC_index (loop_p, GBB_LOOPS (gb), loop_index);
+exit = single_exit (loop);
+niter = find_loop_niter (loop, &exit);
+if (niter == chrec_dont_know
+|| TREE_CODE (niter) != INTEGER_CST)
+return true;
+niter_val = int_cst_value (niter);
+if (niter_val < stride)
+{
+res = false;
+if (dump_file && (dump_flags & TDF_DETAILS))
+	{
+	  fprintf (dump_file, "\nStrip Mining is not profitable for loop %d:",
+		   loop->num);
+	  fprintf (dump_file, "number of iterations is too low.\n");
+	}
+}
+return res;
+}
+/* Determines when the interchange of LOOP_A and LOOP_B belonging to
+SCOP is legal.  DEPTH is the number of loops around.  */
+static bool
+is_interchange_valid (scop_p scop, int loop_a, int loop_b, int depth)
+{
+bool res;
+VEC (ddr_p, heap) *dependence_relations;
+VEC (data_reference_p, heap) *datarefs;
+struct loop *nest = VEC_index (loop_p, SCOP_LOOP_NEST (scop), loop_a);
+lambda_trans_matrix trans;
+gcc_assert (loop_a < loop_b);
+dependence_relations = VEC_alloc (ddr_p, heap, 10 * 10);
+datarefs = VEC_alloc (data_reference_p, heap, 10);
+if (!compute_data_dependences_for_loop (nest, true, &datarefs,
+					  &dependence_relations))
+return false;
+if (dump_file && (dump_flags & TDF_DETAILS))
+dump_ddrs (dump_file, dependence_relations);
+trans = lambda_trans_matrix_new (depth, depth);
+lambda_matrix_id (LTM_MATRIX (trans), depth);
+lambda_matrix_row_exchange (LTM_MATRIX (trans), 0, loop_b - loop_a);
+if (!lambda_transform_legal_p (trans, depth, dependence_relations))
+{
+lambda_matrix_row_exchange (LTM_MATRIX (trans), 0, loop_b - loop_a);
+res = false;
+}
+else
+res = true;
+free_dependence_relations (dependence_relations);
+free_data_refs (datarefs);
+return res;
+}
+/* Loop block the LOOPS innermost loops of GB with stride size STRIDE.
+Example
+for (i = 0; i <= 50; i++=4)
+for (k = 0; k <= 100; k++=4)
+for (l = 0; l <= 200; l++=4)
+A
+To strip mine the two inner most loops with stride = 4 call:
+graphite_trans_bb_block (A, 4, 2)
+for (i = 0; i <= 50; i++)
+for (kk = 0; kk <= 100; kk+=4)
+for (ll = 0; ll <= 200; ll+=4)
+for (k = kk; k <= min (100, kk + 3); k++)
+for (l = ll; l <= min (200, ll + 3); l++)
+A
+*/
+static bool
+graphite_trans_bb_block (graphite_bb_p gb, int stride, int loops)
+{
+int i, j;
+int nb_loops = gbb_nb_loops (gb);
+int start = nb_loops - loops;
+scop_p scop = GBB_SCOP (gb);
+gcc_assert (scop_contains_loop (scop, gbb_loop (gb)));
+for (i = start ; i < nb_loops; i++)
+for (j = i + 1; j < nb_loops; j++)
+if (!is_interchange_valid (scop, i, j, nb_loops))
+	{
+	  if (dump_file && (dump_flags & TDF_DETAILS))
+	    fprintf (dump_file,
+		     "\nInterchange not valid for loops %d and %d:\n", i, j);
+	  return false;
+	}
+else if (dump_file && (dump_flags & TDF_DETAILS))
+	fprintf (dump_file,
+		 "\nInterchange valid for loops %d and %d:\n", i, j);
+/* Check if strip mining is profitable for every loop.  */
+for (i = 0; i < nb_loops - start; i++)
+if (!strip_mine_profitable_p (gb, stride, start + i))
+return false;
+/* Strip mine loops.  */
+for (i = 0; i < nb_loops - start; i++)
+graphite_trans_bb_strip_mine (gb, start + 2 * i, stride);
+/* Interchange loops.  */
+for (i = 1; i < nb_loops - start; i++)
+graphite_trans_bb_move_loop (gb, start + 2 * i, start + i);
+if (dump_file && (dump_flags & TDF_DETAILS))
+fprintf (dump_file, "\nLoops containing BB %d will be loop blocked.\n",
+	     GBB_BB (gb)->index);
+return true;
+}
+/* Loop block LOOPS innermost loops of a loop nest.  BBS represent the
+basic blocks that belong to the loop nest to be blocked.  */
+static bool
+graphite_trans_loop_block (VEC (graphite_bb_p, heap) *bbs, int loops)
+{
+graphite_bb_p gb;
+int i;
+bool transform_done = false;
+/* TODO: - Calculate the stride size automatically.  */
+int stride_size = 51;
+for (i = 0; VEC_iterate (graphite_bb_p, bbs, i, gb); i++)
+transform_done |= graphite_trans_bb_block (gb, stride_size, loops);
+return transform_done;
+}
+/* Loop block all basic blocks of SCOP.  Return false when the
+transform is not performed.  */
+static bool
+graphite_trans_scop_block (scop_p scop)
+{
+graphite_bb_p gb;
+int i, j;
+int last_nb_loops;
+int nb_loops;
+bool perfect = true;
+bool transform_done = false;
+VEC (graphite_bb_p, heap) *bbs = VEC_alloc (graphite_bb_p, heap, 3);
+int max_schedule = scop_max_loop_depth (scop) + 1;
+lambda_vector last_schedule = lambda_vector_new (max_schedule);
+if (VEC_length (graphite_bb_p, SCOP_BBS (scop)) == 0)
+return false;
+/* Get the data of the first bb.  */
+gb = VEC_index (graphite_bb_p, SCOP_BBS (scop), 0);
+last_nb_loops = gbb_nb_loops (gb);
+lambda_vector_copy (GBB_STATIC_SCHEDULE (gb), last_schedule,
+last_nb_loops + 1);
+VEC_safe_push (graphite_bb_p, heap, bbs, gb);
+for (i = 0; VEC_iterate (graphite_bb_p, SCOP_BBS (scop), i, gb); i++)
+{
+/* We did the first bb before.  */
+if (i == 0)
+continue;
+nb_loops = gbb_nb_loops (gb);
+/* If the number of loops is unchanged and only the last element of the
+schedule changes, we stay in the loop nest.  */
+if (nb_loops == last_nb_loops
+&& (last_schedule [nb_loops + 1]
+!= GBB_STATIC_SCHEDULE (gb)[nb_loops + 1]))
+{
+VEC_safe_push (graphite_bb_p, heap, bbs, gb);
+continue;
+}
+/* Otherwise, we left the innermost loop. So check, if the last bb was in
+a perfect loop nest and how many loops are contained in this perfect
+loop nest.
+Count the number of zeros from the end of the schedule. They are the
+number of surrounding loops.
+Example:
+last_bb  2 3 2 0 0 0 0 3
+bb       2 4 0
+	 <------  j = 4
+last_bb  2 3 2 0 0 0 0 3
+bb       2 3 2 0 1
+	 <--  j = 2
+If there is no zero, there were other bbs in outer loops and the loop
+nest is not perfect.  */
+for (j = last_nb_loops - 1; j >= 0; j--)
+{
+if (last_schedule [j] != 0
+|| (j <= nb_loops && GBB_STATIC_SCHEDULE (gb)[j] == 1))
+{
+j--;
+break;
+}
+}
+j++;
+/* Found perfect loop nest.  */
+if (perfect && last_nb_loops - j >= 2)
+transform_done |= graphite_trans_loop_block (bbs, last_nb_loops - j);
+/* Check if we start with a new loop.
+Example:
+last_bb  2 3 2 0 0 0 0 3
+bb       2 3 2 0 0 1 0
+Here we start with the loop "2 3 2 0 0 1"
+last_bb  2 3 2 0 0 0 0 3
+bb       2 3 2 0 0 1
+But here not, so the loop nest can never be perfect.  */
+perfect = (GBB_STATIC_SCHEDULE (gb)[nb_loops] == 0);
+/* Update the last_bb infos.  We do not do that for the bbs in the same
+loop, as the data we use is not changed.  */
+last_nb_loops = nb_loops;
+lambda_vector_copy (GBB_STATIC_SCHEDULE (gb), last_schedule,
+nb_loops + 1);
+VEC_truncate (graphite_bb_p, bbs, 0);
+VEC_safe_push (graphite_bb_p, heap, bbs, gb);
+}
+/* Check if the last loop nest was perfect.  It is the same check as above,
+but the comparison with the next bb is missing.  */
+for (j = last_nb_loops - 1; j >= 0; j--)
+if (last_schedule [j] != 0)
+{
+	j--;
+	break;
+}
+j++;
+/* Found perfect loop nest.  */
+if (last_nb_loops - j >= 2)
+transform_done |= graphite_trans_loop_block (bbs, last_nb_loops - j);
+VEC_free (graphite_bb_p, heap, bbs);
+return transform_done;
+}
+/* Apply graphite transformations to all the basic blocks of SCOP.  */
+static bool
+graphite_apply_transformations (scop_p scop)
+{
+bool transform_done = false;
+/* Sort the list of bbs.  Keep them always sorted.  */
+graphite_sort_gbbs (scop);
+if (flag_loop_block)
+transform_done = graphite_trans_scop_block (scop);
+/* Generate code even if we did not apply any real transformation.
+This also allows to check the performance for the identity
+transformation: GIMPLE -> GRAPHITE -> GIMPLE
+Keep in mind that CLooG optimizes in control, so the loop structure
+may change, even if we only use -fgraphite-identity.  */
+if (flag_graphite_identity)
+transform_done = true;
+return transform_done;
+}
+/* We limit all SCoPs to SCoPs, that are completely surrounded by a loop.
+Example:
+for (i      |
+{         |
+for (j  |  SCoP 1
+for (k  |
+}         |
+* SCoP frontier, as this line is not surrounded by any loop. *
+for (l      |  SCoP 2
+This is necessary as scalar evolution and parameter detection need a
+outermost loop to initialize parameters correctly.
+TODO: FIX scalar evolution and parameter detection to allow more flexible
+SCoP frontiers.  */
+static void
+limit_scops (void)
+{
+VEC (sd_region, heap) *tmp_scops = VEC_alloc (sd_region, heap, 3);
+int i;
+scop_p scop;
+for (i = 0; VEC_iterate (scop_p, current_scops, i, scop); i++)
+{
+int j;
+loop_p loop;
+build_scop_bbs (scop);
+if (!build_scop_loop_nests (scop))
+	continue;
+for (j = 0; VEC_iterate (loop_p, SCOP_LOOP_NEST (scop), j, loop); j++)
+if (!loop_in_sese_p (loop_outer (loop), SCOP_REGION (scop)))
+{
+	    sd_region open_scop;
+	    open_scop.entry = loop->header;
+	    open_scop.exit = single_exit (loop)->dest;
+	    VEC_safe_push (sd_region, heap, tmp_scops, &open_scop);
+	  }
+}
+free_scops (current_scops);
+current_scops = VEC_alloc (scop_p, heap, 3);
+create_sese_edges (tmp_scops);
+build_graphite_scops (tmp_scops);
+VEC_free (sd_region, heap, tmp_scops);
+}
+/* Perform a set of linear transforms on the loops of the current
+function.  */
+void
+graphite_transform_loops (void)
+{
+int i;
+scop_p scop;
+bool transform_done = false;
+if (number_of_loops () <= 1)
+return;
+current_scops = VEC_alloc (scop_p, heap, 3);
+recompute_all_dominators ();
+if (dump_file && (dump_flags & TDF_DETAILS))
+fprintf (dump_file, "Graphite loop transformations \n");
+initialize_original_copy_tables ();
+cloog_initialize ();
+build_scops ();
+limit_scops ();
+if (dump_file && (dump_flags & TDF_DETAILS))
+fprintf (dump_file, "\nnumber of SCoPs: %d\n",
+	     VEC_length (scop_p, current_scops));
+for (i = 0; VEC_iterate (scop_p, current_scops, i, scop); i++)
+{
+build_scop_bbs (scop);
+if (!build_scop_loop_nests (scop))
+	continue;
+build_bb_loops (scop);
+if (!build_scop_conditions (scop))
+	continue;
+find_scop_parameters (scop);
+build_scop_context (scop);
+if (dump_file && (dump_flags & TDF_DETAILS))
+	{
+	  fprintf (dump_file, "\n(In SCoP %d:\n", i);
+	  fprintf (dump_file, "\nnumber of bbs: %d\n",
+		   VEC_length (graphite_bb_p, SCOP_BBS (scop)));
+	  fprintf (dump_file, "\nnumber of loops: %d)\n",
+		   VEC_length (loop_p, SCOP_LOOP_NEST (scop)));
+	}
+if (!build_scop_iteration_domain (scop))
+	continue;
+add_conditions_to_constraints (scop);
+build_scop_canonical_schedules (scop);
+build_scop_data_accesses (scop);
+build_scop_dynamic_schedules (scop);
+if (dump_file && (dump_flags & TDF_DETAILS))
+	{
+	  int nbrefs = nb_data_refs_in_scop (scop);
+	  fprintf (dump_file, "\nnumber of data refs: %d\n", nbrefs);
+	}
+if (graphite_apply_transformations (scop))
+transform_done = gloog (scop, find_transform (scop));
+#ifdef ENABLE_CHECKING
+else
+	{
+	  struct clast_stmt *stmt = find_transform (scop);
+	  cloog_clast_free (stmt);
+	}
+#endif
+}
+/* Cleanup.  */
+if (transform_done)
+cleanup_tree_cfg ();
+free_scops (current_scops);
+cloog_finalize ();
+free_original_copy_tables ();
+}
+#else /* If Cloog is not available: #ifndef HAVE_cloog.  */
+void
+graphite_transform_loops (void)
+{
+sorry ("Graphite loop optimizations cannot be used");
+}
+#endif

Mercurial > hg > CbC > CbC_gcc

comparison gcc/graphite.c @ 0:a06113de4d67