2005-06-14 Ed Schonberg <schonberg@adacore.com>

[pf3gnuchains/gcc-fork.git] / gcc / tree-data-ref.c

diff --git a/gcc/tree-data-ref.c b/gcc/tree-data-ref.c
index 50b805b..e4917df 100644 (file)
--- a/gcc/tree-data-ref.c
+++ b/gcc/tree-data-ref.c
@@ -447,32 +447,21 @@ dump_ddrs (FILE *file, varray_type ddrs)
 
 \f
 
-/* Compute the lowest iteration bound for LOOP.  It is an
-   INTEGER_CST.  */
+/* Initialize LOOP->ESTIMATED_NB_ITERATIONS with the lowest safe
+   approximation of the number of iterations for LOOP.  */
 
 static void
 compute_estimated_nb_iterations (struct loop *loop)
 {
-  tree estimation;
-  struct nb_iter_bound *bound, *next;
-  
-  for (bound = loop->bounds; bound; bound = next)
-    {
-      next = bound->next;
-      estimation = bound->bound;
-
-      if (TREE_CODE (estimation) != INTEGER_CST)
-       continue;
-
-      if (loop->estimated_nb_iterations)
-       {
-         /* Update only if estimation is smaller.  */
-         if (tree_int_cst_lt (estimation, loop->estimated_nb_iterations))
-           loop->estimated_nb_iterations = estimation;
-       }
-      else
-       loop->estimated_nb_iterations = estimation;
-    }
+  struct nb_iter_bound *bound;
+  
+  for (bound = loop->bounds; bound; bound = bound->next)
+    if (TREE_CODE (bound->bound) == INTEGER_CST
+       /* Update only when there is no previous estimation.  */
+       && (chrec_contains_undetermined (loop->estimated_nb_iterations)
+           /* Or when the current estimation is smaller.  */
+           || tree_int_cst_lt (bound->bound, loop->estimated_nb_iterations)))
+      loop->estimated_nb_iterations = bound->bound;
 }
 
 /* Estimate the number of iterations from the size of the data and the
@@ -538,7 +527,7 @@ analyze_array_indexes (struct loop *loop,
   access_fn = instantiate_parameters 
     (loop, analyze_scalar_evolution (loop, opnd1));
 
-  if (loop->estimated_nb_iterations == NULL_TREE)
+  if (chrec_contains_undetermined (loop->estimated_nb_iterations))
     estimate_niter_from_size_of_data (loop, opnd0, access_fn, stmt);
   
   VEC_safe_push (tree, heap, *access_fns, access_fn);
@@ -1129,8 +1118,12 @@ compute_overlap_steps_for_affine_1_2 (tree chrec_a, tree chrec_b,
     numiter_z = current_loops->parray[CHREC_VARIABLE (chrec_b)]
       ->estimated_nb_iterations;
 
-  if (numiter_x == NULL_TREE || numiter_y == NULL_TREE 
-      || numiter_z == NULL_TREE)
+  if (chrec_contains_undetermined (numiter_x)
+      || chrec_contains_undetermined (numiter_y)
+      || chrec_contains_undetermined (numiter_z)
+      || TREE_CODE (numiter_x) != INTEGER_CST
+      || TREE_CODE (numiter_y) != INTEGER_CST
+      || TREE_CODE (numiter_z) != INTEGER_CST)
     {
       *overlaps_a = chrec_dont_know;
       *overlaps_b = chrec_dont_know;
@@ -1278,7 +1271,10 @@ analyze_subscript_affine_affine (tree chrec_a,
          if (TREE_CODE (numiter_b) != INTEGER_CST)
            numiter_b = current_loops->parray[CHREC_VARIABLE (chrec_b)]
              ->estimated_nb_iterations;
-         if (numiter_a == NULL_TREE || numiter_b == NULL_TREE)
+         if (chrec_contains_undetermined (numiter_a)
+             || chrec_contains_undetermined (numiter_b)
+             || TREE_CODE (numiter_a) != INTEGER_CST
+             || TREE_CODE (numiter_b) != INTEGER_CST)
            {
              *overlaps_a = chrec_dont_know;
              *overlaps_b = chrec_dont_know;
@@ -1379,7 +1375,10 @@ analyze_subscript_affine_affine (tree chrec_a,
          if (TREE_CODE (numiter_b) != INTEGER_CST)
            numiter_b = current_loops->parray[CHREC_VARIABLE (chrec_b)]
              ->estimated_nb_iterations;
-         if (numiter_a == NULL_TREE || numiter_b == NULL_TREE)
+         if (chrec_contains_undetermined (numiter_a)
+             || chrec_contains_undetermined (numiter_b)
+             || TREE_CODE (numiter_a) != INTEGER_CST
+             || TREE_CODE (numiter_b) != INTEGER_CST)
            {
              *overlaps_a = chrec_dont_know;
              *overlaps_b = chrec_dont_know;
@@ -2344,11 +2343,11 @@ find_data_references_in_loop (struct loop *loop, varray_type *datarefs)
 
          /* When there are no defs in the loop, the loop is parallel.  */
          if (!ZERO_SSA_OPERANDS (stmt, SSA_OP_VIRTUAL_DEFS))
-           bb->loop_father->parallel_p = false;
+           loop->parallel_p = false;
        }
 
-      if (bb->loop_father->estimated_nb_iterations == NULL_TREE)
-       compute_estimated_nb_iterations (bb->loop_father);
+      if (chrec_contains_undetermined (loop->estimated_nb_iterations))
+       compute_estimated_nb_iterations (loop);
     }
 
   free (bbs);