1 files changed, 584 insertions, 3 deletions

diff --git a/gcc/graphite-isl-ast-to-gimple.c b/gcc/graphite-isl-ast-to-gimple.c
index 2bd8250..a8dfe7b 100644
--- a/gcc/graphite-isl-ast-to-gimple.c
+++ b/gcc/graphite-isl-ast-to-gimple.c
@@ -25,6 +25,13 @@ along with GCC; see the file COPYING3.  If not see
 #include <isl/map.h>
 #include <isl/union_map.h>
 #include <isl/ast_build.h>
+#if defined(__cplusplus)
+extern "C" {
+#endif
+#include <isl/val_gmp.h>
+#if defined(__cplusplus)
+}
+#endif
 #endif
 
 #include "system.h"
@@ -42,6 +49,9 @@ along with GCC; see the file COPYING3.  If not see
 #include "cfgloop.h"
 #include "tree-data-ref.h"
 #include "sese.h"
+#include "tree-ssa-loop-manip.h"
+#include "tree-scalar-evolution.h"
+#include <map>
 
 #ifdef HAVE_cloog
 #include "graphite-poly.h"
@@ -52,6 +62,515 @@ along with GCC; see the file COPYING3.  If not see
 
 static bool graphite_regenerate_error;
 
+/* We always use signed 128, until isl is able to give information about
+types  */
+
+static tree *graphite_expression_size_type = &int128_integer_type_node;
+
+/* Converts a GMP constant VAL to a tree and returns it.  */
+
+static tree
+gmp_cst_to_tree (tree type, mpz_t val)
+{
+  tree t = type ? type : integer_type_node;
+  mpz_t tmp;
+
+  mpz_init (tmp);
+  mpz_set (tmp, val);
+  wide_int wi = wi::from_mpz (t, tmp, true);
+  mpz_clear (tmp);
+
+  return wide_int_to_tree (t, wi);
+}
+
+/* Verifies properties that GRAPHITE should maintain during translation.  */
+
+static inline void
+graphite_verify (void)
+{
+#ifdef ENABLE_CHECKING
+  verify_loop_structure ();
+  verify_loop_closed_ssa (true);
+#endif
+}
+
+/* IVS_PARAMS maps ISL's scattering and parameter identifiers
+   to corresponding trees.  */
+
+typedef std::map<isl_id *, tree> ivs_params;
+
+/* Free all memory allocated for ISL's identifiers.  */
+
+void ivs_params_clear (ivs_params &ip)
+{
+  std::map<isl_id *, tree>::iterator it;
+  for (it = ip.begin ();
+       it != ip.end (); it++)
+    {
+      isl_id_free (it->first);
+    }
+}
+
+static tree
+gcc_expression_from_isl_expression (tree type, __isl_take isl_ast_expr *,
+				    ivs_params &ip);
+
+/* Return the tree variable that corresponds to the given isl ast identifier
+ expression (an isl_ast_expr of type isl_ast_expr_id).  */
+
+static tree
+gcc_expression_from_isl_ast_expr_id (__isl_keep isl_ast_expr *expr_id,
+				     ivs_params &ip)
+{
+  gcc_assert (isl_ast_expr_get_type (expr_id) == isl_ast_expr_id);
+  isl_id *tmp_isl_id = isl_ast_expr_get_id (expr_id);
+  std::map<isl_id *, tree>::iterator res;
+  res = ip.find (tmp_isl_id);
+  isl_id_free (tmp_isl_id);
+  gcc_assert (res != ip.end () &&
+              "Could not map isl_id to tree expression");
+  isl_ast_expr_free (expr_id);
+  return res->second;
+}
+
+/* Converts an isl_ast_expr_int expression E to a GCC expression tree of
+   type TYPE.  */
+
+static tree
+gcc_expression_from_isl_expr_int (tree type, __isl_take isl_ast_expr *expr)
+{
+  gcc_assert (isl_ast_expr_get_type (expr) == isl_ast_expr_int);
+  isl_val *val = isl_ast_expr_get_val (expr);
+  mpz_t val_mpz_t;
+  mpz_init (val_mpz_t);
+  tree res;
+  if (isl_val_get_num_gmp (val, val_mpz_t) == -1)
+    res = NULL_TREE;
+  else
+    res = gmp_cst_to_tree (type, val_mpz_t);
+  isl_val_free (val);
+  isl_ast_expr_free (expr);
+  mpz_clear (val_mpz_t);
+  return res;
+}
+
+/* Converts a binary isl_ast_expr_op expression E to a GCC expression tree of
+   type TYPE.  */
+
+static tree
+binary_op_to_tree (tree type, __isl_take isl_ast_expr *expr, ivs_params &ip)
+{
+  isl_ast_expr *arg_expr = isl_ast_expr_get_op_arg (expr, 0);
+  tree tree_lhs_expr = gcc_expression_from_isl_expression (type, arg_expr, ip);
+  arg_expr = isl_ast_expr_get_op_arg (expr, 1);
+  tree tree_rhs_expr = gcc_expression_from_isl_expression (type, arg_expr, ip);
+  enum isl_ast_op_type expr_type = isl_ast_expr_get_op_type (expr);
+  isl_ast_expr_free (expr);
+  switch (expr_type)
+    {
+    case isl_ast_op_add:
+      return fold_build2 (PLUS_EXPR, type, tree_lhs_expr, tree_rhs_expr);
+
+    case isl_ast_op_sub:
+      return fold_build2 (MINUS_EXPR, type, tree_lhs_expr, tree_rhs_expr);
+
+    case isl_ast_op_mul:
+      return fold_build2 (MULT_EXPR, type, tree_lhs_expr, tree_rhs_expr);
+
+    case isl_ast_op_div:
+      return fold_build2 (EXACT_DIV_EXPR, type, tree_lhs_expr, tree_rhs_expr);
+
+    case isl_ast_op_fdiv_q:
+      return fold_build2 (FLOOR_DIV_EXPR, type, tree_lhs_expr, tree_rhs_expr);
+
+    case isl_ast_op_and:
+      return fold_build2 (TRUTH_ANDIF_EXPR, type,
+			  tree_lhs_expr, tree_rhs_expr);
+
+    case isl_ast_op_or:
+      return fold_build2 (TRUTH_ORIF_EXPR, type, tree_lhs_expr, tree_rhs_expr);
+
+    case isl_ast_op_eq:
+      return fold_build2 (EQ_EXPR, type, tree_lhs_expr, tree_rhs_expr);
+
+    case isl_ast_op_le:
+      return fold_build2 (LE_EXPR, type, tree_lhs_expr, tree_rhs_expr);
+
+    case isl_ast_op_lt:
+      return fold_build2 (LT_EXPR, type, tree_lhs_expr, tree_rhs_expr);
+
+    case isl_ast_op_ge:
+      return fold_build2 (GE_EXPR, type, tree_lhs_expr, tree_rhs_expr);
+
+    case isl_ast_op_gt:
+      return fold_build2 (GT_EXPR, type, tree_lhs_expr, tree_rhs_expr);
+
+    default:
+      gcc_unreachable ();
+    }
+}
+
+/* Converts a ternary isl_ast_expr_op expression E to a GCC expression tree of
+   type TYPE.  */
+
+static tree
+ternary_op_to_tree (tree type, __isl_take isl_ast_expr *expr, ivs_params &ip)
+{
+  gcc_assert (isl_ast_expr_get_op_type (expr) == isl_ast_op_minus);
+  isl_ast_expr *arg_expr = isl_ast_expr_get_op_arg (expr, 0);
+  tree tree_first_expr
+    = gcc_expression_from_isl_expression (type, arg_expr, ip);
+  arg_expr = isl_ast_expr_get_op_arg (expr, 1);
+  tree tree_second_expr
+    = gcc_expression_from_isl_expression (type, arg_expr, ip);
+  arg_expr = isl_ast_expr_get_op_arg (expr, 2);
+  tree tree_third_expr
+    = gcc_expression_from_isl_expression (type, arg_expr, ip);
+  isl_ast_expr_free (expr);
+  return fold_build3 (COND_EXPR, type, tree_first_expr,
+		      tree_second_expr, tree_third_expr);
+}
+
+/* Converts a unary isl_ast_expr_op expression E to a GCC expression tree of
+   type TYPE.  */
+
+static tree
+unary_op_to_tree (tree type, __isl_take isl_ast_expr *expr, ivs_params &ip)
+{
+  gcc_assert (isl_ast_expr_get_op_type (expr) == isl_ast_op_minus);
+  isl_ast_expr *arg_expr = isl_ast_expr_get_op_arg (expr, 0);
+  tree tree_expr = gcc_expression_from_isl_expression (type, arg_expr, ip);
+  isl_ast_expr_free (expr);
+  return fold_build1 (NEGATE_EXPR, type, tree_expr);
+}
+
+/* Converts an isl_ast_expr_op expression E with unknown number of arguments
+   to a GCC expression tree of type TYPE.  */
+
+static tree
+nary_op_to_tree (tree type, __isl_take isl_ast_expr *expr, ivs_params &ip)
+{
+  enum tree_code op_code;
+  switch (isl_ast_expr_get_op_type (expr))
+    {
+    case isl_ast_op_max:
+      op_code = MAX_EXPR;
+      break;
+
+    case isl_ast_op_min:
+      op_code = MIN_EXPR;
+      break;
+
+    default:
+      gcc_unreachable ();    
+    }
+  isl_ast_expr *arg_expr = isl_ast_expr_get_op_arg (expr, 0);
+  tree res = gcc_expression_from_isl_expression (type, arg_expr, ip);
+  int i;
+  for (i = 1; i < isl_ast_expr_get_op_n_arg (expr); i++)
+    {
+      arg_expr = isl_ast_expr_get_op_arg (expr, i);
+      tree t = gcc_expression_from_isl_expression (type, arg_expr, ip);
+      res = fold_build2 (op_code, type, res, t);
+    }
+  isl_ast_expr_free (expr);
+  return res;
+}
+
+
+/* Converts an isl_ast_expr_op expression E to a GCC expression tree of
+   type TYPE.  */
+
+static tree
+gcc_expression_from_isl_expr_op (tree type, __isl_take isl_ast_expr *expr,
+				 ivs_params &ip)
+{
+  gcc_assert (isl_ast_expr_get_type (expr) == isl_ast_expr_op);
+  switch (isl_ast_expr_get_op_type (expr))
+    {
+    /* These isl ast expressions are not supported yet.  */
+    case isl_ast_op_error:
+    case isl_ast_op_call:
+    case isl_ast_op_and_then:
+    case isl_ast_op_or_else:
+    case isl_ast_op_pdiv_q:
+    case isl_ast_op_pdiv_r:
+    case isl_ast_op_select:
+      gcc_unreachable ();
+
+    case isl_ast_op_max:
+    case isl_ast_op_min:
+      return nary_op_to_tree (type, expr, ip);
+
+    case isl_ast_op_add:
+    case isl_ast_op_sub:
+    case isl_ast_op_mul:
+    case isl_ast_op_div:
+    case isl_ast_op_fdiv_q:
+    case isl_ast_op_and:
+    case isl_ast_op_or:
+    case isl_ast_op_eq:
+    case isl_ast_op_le:
+    case isl_ast_op_lt:
+    case isl_ast_op_ge:
+    case isl_ast_op_gt:
+      return binary_op_to_tree (type, expr, ip);
+
+    case isl_ast_op_minus:
+      return unary_op_to_tree (type, expr, ip);
+
+    case isl_ast_op_cond:
+      return ternary_op_to_tree (type, expr, ip);
+
+    default:
+      gcc_unreachable ();
+    }
+
+  return NULL_TREE;
+}
+
+/* Converts an ISL AST expression E back to a GCC expression tree of
+   type TYPE.  */
+
+static tree
+gcc_expression_from_isl_expression (tree type, __isl_take isl_ast_expr *expr,
+				    ivs_params &ip)
+{
+  switch (isl_ast_expr_get_type (expr))
+    {
+    case isl_ast_expr_id:
+      return gcc_expression_from_isl_ast_expr_id (expr, ip);
+
+    case isl_ast_expr_int:
+      return gcc_expression_from_isl_expr_int (type, expr);
+
+    case isl_ast_expr_op:
+      return gcc_expression_from_isl_expr_op (type, expr, ip);
+
+    default:
+      gcc_unreachable ();
+    }
+
+  return NULL_TREE;
+}
+
+/* Creates a new LOOP corresponding to isl_ast_node_for.  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.  NEWIVS_INDEX binds
+   ISL's scattering name to the induction variable created for the
+   loop of STMT.  The new induction variable is inserted in the NEWIVS
+   vector and is of type TYPE.  */
+
+static struct loop *
+graphite_create_new_loop (edge entry_edge, __isl_keep isl_ast_node *node_for,
+			  loop_p outer, tree type, tree lb, tree ub,
+			  ivs_params &ip)
+{
+  isl_ast_expr *for_inc = isl_ast_node_for_get_inc (node_for);
+  tree stride = gcc_expression_from_isl_expression (type, for_inc, ip);
+  tree ivvar = create_tmp_var (type, "graphite_IV");
+  tree iv, iv_after_increment;
+  loop_p loop = create_empty_loop_on_edge
+    (entry_edge, lb, stride, ub, ivvar, &iv, &iv_after_increment,
+     outer ? outer : entry_edge->src->loop_father);
+
+  isl_ast_expr *for_iterator = isl_ast_node_for_get_iterator (node_for);
+  isl_id *id = isl_ast_expr_get_id (for_iterator);
+  ip[id] = iv;
+  isl_ast_expr_free (for_iterator);
+  return loop;
+}
+
+static edge
+translate_isl_ast (loop_p context_loop, __isl_keep isl_ast_node *node,
+		   edge next_e, ivs_params &ip);
+
+/* Create the loop for a isl_ast_node_for.
+
+   - NEXT_E is the edge where new generated code should be attached.  */
+
+static edge
+translate_isl_ast_for_loop (loop_p context_loop,
+			    __isl_keep isl_ast_node *node_for, edge next_e,
+			    tree type, tree lb, tree ub,
+			    ivs_params &ip)
+{
+  gcc_assert (isl_ast_node_get_type (node_for) == isl_ast_node_for);
+  struct loop *loop = graphite_create_new_loop (next_e, node_for, context_loop,
+						type, lb, ub, ip);
+  edge last_e = single_exit (loop);
+  edge to_body = single_succ_edge (loop->header);
+  basic_block after = to_body->dest;
+
+  /* Create a basic block for loop close phi nodes.  */
+  last_e = single_succ_edge (split_edge (last_e));
+
+  /* Translate the body of the loop.  */
+  isl_ast_node *for_body = isl_ast_node_for_get_body (node_for);
+  next_e = translate_isl_ast (loop, for_body, to_body, ip);
+  isl_ast_node_free (for_body);
+  redirect_edge_succ_nodup (next_e, after);
+  set_immediate_dominator (CDI_DOMINATORS, next_e->dest, next_e->src);
+
+  /* TODO: Add checking for the loop parallelism.  */
+
+  return last_e;
+}
+
+/* We use this function to get the upper bound because of the form,
+   which is used by isl to represent loops:
+
+   for (iterator = init; cond; iterator += inc)
+
+   {
+
+     ...
+
+   }
+
+   The loop condition is an arbitrary expression, which contains the
+   current loop iterator.
+
+   (e.g. iterator + 3 < B && C > iterator + A)
+
+   We have to know the upper bound of the iterator to generate a loop
+   in Gimple form. It can be obtained from the special representation
+   of the loop condition, which is generated by isl,
+   if the ast_build_atomic_upper_bound option is set. In this case,
+   isl generates a loop condition that consists of the current loop
+   iterator, + an operator (< or <=) and an expression not involving
+   the iterator, which is processed and returned by this function.
+
+   (e.g iterator <= upper-bound-expression-without-iterator)  */
+
+static __isl_give isl_ast_expr *
+get_upper_bound (__isl_keep isl_ast_node *node_for)
+{
+  gcc_assert (isl_ast_node_get_type (node_for) == isl_ast_node_for);
+  isl_ast_expr *for_cond = isl_ast_node_for_get_cond (node_for);
+  gcc_assert (isl_ast_expr_get_type (for_cond) == isl_ast_expr_op);
+  isl_ast_expr *res;
+  switch (isl_ast_expr_get_op_type (for_cond))
+    {
+    case isl_ast_op_le:
+      res = isl_ast_expr_get_op_arg (for_cond, 1);
+      break;
+
+    case isl_ast_op_lt:
+      {
+        // (iterator < ub) => (iterator <= ub - 1)
+        isl_val *one = isl_val_int_from_si (isl_ast_expr_get_ctx (for_cond), 1);
+        isl_ast_expr *ub = isl_ast_expr_get_op_arg (for_cond, 1);
+        res = isl_ast_expr_sub (ub, isl_ast_expr_from_val (one));
+        break;
+      }
+
+    default:
+      gcc_unreachable ();
+    }
+  isl_ast_expr_free (for_cond);
+  return res;
+}
+
+/* All loops generated by create_empty_loop_on_edge have the form of
+   a post-test loop:
+
+   do
+
+   {
+     body of the loop;
+   } while (lower bound < upper bound);
+
+   We create a new if region protecting the loop to be executed, if
+   the execution count is zero (lower bound > upper bound).  */
+
+static edge
+graphite_create_new_loop_guard (edge entry_edge,
+				__isl_keep isl_ast_node *node_for, tree *type,
+				tree *lb, tree *ub, ivs_params &ip)
+{
+  gcc_assert (isl_ast_node_get_type (node_for) == isl_ast_node_for);
+  tree cond_expr;
+  edge exit_edge;
+
+  *type = *graphite_expression_size_type;
+  isl_ast_expr *for_init = isl_ast_node_for_get_init (node_for);
+  *lb = gcc_expression_from_isl_expression (*type, for_init, ip);
+  isl_ast_expr *upper_bound = get_upper_bound (node_for);
+  *ub = gcc_expression_from_isl_expression (*type, upper_bound, ip);
+  
+  /* When ub is simply a constant or a parameter, use lb <= ub.  */
+  if (TREE_CODE (*ub) == INTEGER_CST || TREE_CODE (*ub) == SSA_NAME)
+    cond_expr = fold_build2 (LE_EXPR, boolean_type_node, *lb, *ub);
+  else
+    {
+      tree one = (POINTER_TYPE_P (*type)
+		  ? convert_to_ptrofftype (integer_one_node)
+		  : fold_convert (*type, integer_one_node));
+      /* Adding +1 and using LT_EXPR helps with loop latches that have a
+	 loop iteration count of "PARAMETER - 1".  For PARAMETER == 0 this
+	 becomes 2^k-1 due to integer overflow, and the condition lb <= ub
+	 is true, even if we do not want this.  However lb < ub + 1 is false,
+	 as expected.  */
+      tree ub_one = fold_build2 (POINTER_TYPE_P (*type) ? POINTER_PLUS_EXPR
+				 : PLUS_EXPR, *type, *ub, one);
+
+      cond_expr = fold_build2 (LT_EXPR, boolean_type_node, *lb, ub_one);
+    }
+
+  exit_edge = create_empty_if_region_on_edge (entry_edge, cond_expr);
+
+  return exit_edge;
+}
+
+/* Translates an isl_ast_node_for to Gimple. */
+
+static edge
+translate_isl_ast_node_for (loop_p context_loop, __isl_keep isl_ast_node *node,
+			    edge next_e, ivs_params &ip)
+{
+  gcc_assert (isl_ast_node_get_type (node) == isl_ast_node_for);
+  tree type, lb, ub;
+  edge last_e = graphite_create_new_loop_guard (next_e, node, &type,
+						&lb, &ub, ip);
+  edge true_e = get_true_edge_from_guard_bb (next_e->dest);
+
+  translate_isl_ast_for_loop (context_loop, node, true_e,
+			      type, lb, ub, ip);
+  return last_e;
+}
+
+/* Translates an ISL AST node NODE to GCC representation in the
+   context of a SESE.  */
+
+static edge
+translate_isl_ast (loop_p context_loop, __isl_keep isl_ast_node *node,
+		   edge next_e, ivs_params &ip)
+{
+  switch (isl_ast_node_get_type (node))
+    {
+    case isl_ast_node_error:
+      gcc_unreachable ();
+
+    case isl_ast_node_for:
+      return translate_isl_ast_node_for (context_loop, node,
+					 next_e, ip);
+
+    case isl_ast_node_if:
+      return next_e;
+
+    case isl_ast_node_user:
+      return next_e;
+
+    case isl_ast_node_block:
+      return next_e;
+
+    default:
+      gcc_unreachable ();
+    }
+}
+
 /* Prints NODE to FILE.  */
 
 void
@@ -65,6 +584,23 @@ print_isl_ast_node (FILE *file, __isl_keep isl_ast_node *node,
   isl_printer_free (prn);
 }
 
+/* Add ISL's parameter identifiers and corresponding.trees to ivs_params  */
+
+static void
+add_parameters_to_ivs_params (scop_p scop, ivs_params &ip)
+{
+  sese region = SCOP_REGION (scop);
+  unsigned nb_parameters = isl_set_dim (scop->context, isl_dim_param);
+  gcc_assert (nb_parameters == SESE_PARAMS (region).length ());
+  unsigned i;
+  for (i = 0; i < nb_parameters; i++)
+    {
+      isl_id *tmp_id = isl_set_get_dim_id (scop->context, isl_dim_param, i);
+      ip[tmp_id] = SESE_PARAMS (region)[i];
+    }
+}
+
+
 /* Generates a build, which specifies the constraints on the parameters.  */
 
 static __isl_give isl_ast_build *
@@ -103,8 +639,15 @@ generate_isl_schedule (scop_p scop)
 }
 
 static __isl_give isl_ast_node *
-scop_to_isl_ast (scop_p scop)
+scop_to_isl_ast (scop_p scop, ivs_params &ip)
 {
+  /* Generate loop upper bounds that consist of the current loop iterator,
+  an operator (< or <=) and an expression not involving the iterator.
+  If this option is not set, then the current loop iterator may appear several
+  times in the upper bound. See the isl manual for more details.  */
+  isl_options_set_ast_build_atomic_upper_bound (scop->ctx, true);
+
+  add_parameters_to_ivs_params (scop, ip);
   isl_union_map *schedule_isl = generate_isl_schedule (scop);
   isl_ast_build *context_isl = generate_isl_context (scop);
   isl_ast_node *ast_isl = isl_ast_build_ast_from_schedule (context_isl,
@@ -117,21 +660,59 @@ scop_to_isl_ast (scop_p scop)
    the given SCOP.  Return true if code generation succeeded.
 
    FIXME: This is not yet a full implementation of the code generator
-          with ISL ASTs. Generation of GIMPLE code is have to be added.  */
+          with ISL ASTs. Generation of GIMPLE code has to be completed.  */
 
 bool
 graphite_regenerate_ast_isl (scop_p scop)
 {
+  loop_p context_loop;
+  sese region = SCOP_REGION (scop);
+  ifsese if_region = NULL;
+  isl_ast_node *root_node;
+  ivs_params ip;
+
   timevar_push (TV_GRAPHITE_CODE_GEN);
   graphite_regenerate_error = false;
-  isl_ast_node *root_node = scop_to_isl_ast (scop);
+  root_node = scop_to_isl_ast (scop, ip);
+
   if (dump_file && (dump_flags & TDF_DETAILS))
     {
       fprintf (dump_file, "\nISL AST generated by ISL: \n");
       print_isl_ast_node (dump_file, root_node, scop->ctx);
+      fprintf (dump_file, "\n");
     }
+
+  recompute_all_dominators ();
+  graphite_verify ();
+
+  if_region = move_sese_in_condition (region);
+  sese_insert_phis_for_liveouts (region,
+				 if_region->region->exit->src,
+				 if_region->false_region->exit,
+				 if_region->true_region->exit);
+  recompute_all_dominators ();
+  graphite_verify ();
+
+  context_loop = SESE_ENTRY (region)->src->loop_father;
+
+  translate_isl_ast (context_loop, root_node, if_region->true_region->entry,
+		     ip);
+  graphite_verify ();
+  scev_reset ();
+  recompute_all_dominators ();
+  graphite_verify ();
+
+  if (graphite_regenerate_error)
+    set_ifsese_condition (if_region, integer_zero_node);
+
+  free (if_region->true_region);
+  free (if_region->region);
+  free (if_region);
+
+  ivs_params_clear (ip);
   isl_ast_node_free (root_node);
   timevar_pop (TV_GRAPHITE_CODE_GEN);
+  /* TODO: Add dump  */
   return !graphite_regenerate_error;
 }
 #endif