gimplify.c (find_single_pointer_decl_1): New static function.

	* gimplify.c (find_single_pointer_decl_1): New static function.
	(find_single_pointer_decl): New static function.
	(internal_get_tmp_var): For a formal variable, set restrict base
	information if appropriate.
	* alias.c (find_base_decl): If a VAR_DECL has a restrict base,
	return it.
	* tree.h (DECL_BASED_ON_RESTRICT_P): Define.
	(DECL_GET_RESTRICT_BASE): Define.
	(SET_DECL_RESTRICT_BASE): Define.
	(decl_restrict_base_lookup): Declare.
	(decl_restrict_base_insert): Declare.
	(struct tree_decl_with_vis): Add based_on_restrict_p field.
	* tree.c (restrict_base_for_decl): New static variable.
	(init_ttree): Initialize restrict_base_for_decl.
	(copy_node_stat): Copy restrict base information.
	(decl_restrict_base_lookup): New function.
	(decl_restrict_base_insert): New function.
	(print_restrict_base_statistics): New static function.
	(dump_tree_statistics): Call print_restrict_base_statistics.

From-SVN: r104890

5 files changed, 162 insertions, 5 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index e27296f..6a566332 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,25 @@
+2005-10-03  Ian Lance Taylor  <ian@airs.com>
+
+	* gimplify.c (find_single_pointer_decl_1): New static function.
+	(find_single_pointer_decl): New static function.
+	(internal_get_tmp_var): For a formal variable, set restrict base
+	information if appropriate.
+	* alias.c (find_base_decl): If a VAR_DECL has a restrict base,
+	return it.
+	* tree.h (DECL_BASED_ON_RESTRICT_P): Define.
+	(DECL_GET_RESTRICT_BASE): Define.
+	(SET_DECL_RESTRICT_BASE): Define.
+	(decl_restrict_base_lookup): Declare.
+	(decl_restrict_base_insert): Declare.
+	(struct tree_decl_with_vis): Add based_on_restrict_p field.
+	* tree.c (restrict_base_for_decl): New static variable.
+	(init_ttree): Initialize restrict_base_for_decl.
+	(copy_node_stat): Copy restrict base information.
+	(decl_restrict_base_lookup): New function.
+	(decl_restrict_base_insert): New function.
+	(print_restrict_base_statistics): New static function.
+	(dump_tree_statistics): Call print_restrict_base_statistics.
+
 2005-10-02  Diego Novillo  <dnovillo@redhat.com>
 
 	PR 24142
diff --git a/gcc/alias.c b/gcc/alias.c
index 49f712e..4806019 100644
--- a/gcc/alias.c
+++ b/gcc/alias.c
@@ -395,9 +395,14 @@ find_base_decl (tree t)
   if (t == 0 || t == error_mark_node || ! POINTER_TYPE_P (TREE_TYPE (t)))
     return 0;
 
-  /* If this is a declaration, return it.  */
+  /* If this is a declaration, return it.  If T is based on a restrict
+     qualified decl, return that decl.  */
   if (DECL_P (t))
-    return t;
+    {
+      if (TREE_CODE (t) == VAR_DECL && DECL_BASED_ON_RESTRICT_P (t))
+	t = DECL_GET_RESTRICT_BASE (t);
+      return t;
+    }
 
   /* Handle general expressions.  It would be nice to deal with
      COMPONENT_REFs here.  If we could tell that `a' and `b' were the
diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index e5d50e2..7047918 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -298,6 +298,48 @@ create_artificial_label (void)
   return lab;
 }
 
+/* Subroutine for find_single_pointer_decl.  */
+
+static tree
+find_single_pointer_decl_1 (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED,
+			    void *data)
+{
+  tree *pdecl = (tree *) data;
+
+  if (DECL_P (*tp) && POINTER_TYPE_P (TREE_TYPE (*tp)))
+    {
+      if (*pdecl)
+	{
+	  /* We already found a pointer decl; return anything other
+	     than NULL_TREE to unwind from walk_tree signalling that
+	     we have a duplicate.  */
+	  return *tp;
+	}
+      *pdecl = *tp;
+    }
+
+  return NULL_TREE;
+}
+
+/* Find the single DECL of pointer type in the tree T and return it.
+   If there are zero or more than one such DECLs, return NULL.  */
+
+static tree
+find_single_pointer_decl (tree t)
+{
+  tree decl = NULL_TREE;
+
+  if (walk_tree (&t, find_single_pointer_decl_1, &decl, NULL))
+    {
+      /* find_single_pointer_decl_1 returns a non-zero value, causing
+	 walk_tree to return a non-zero value, to indicate that it
+	 found more than one pointer DECL.  */
+      return NULL_TREE;
+    }
+
+  return decl;
+}
+
 /* Create a new temporary name with PREFIX.  Returns an identifier.  */
 
 static GTY(()) unsigned int tmp_var_id_num;
@@ -470,6 +512,24 @@ internal_get_tmp_var (tree val, tree *pre_p, tree *post_p, bool is_formal)
 
   t = lookup_tmp_var (val, is_formal);
 
+  if (is_formal)
+    {
+      tree u = find_single_pointer_decl (val);
+
+      if (u && TREE_CODE (u) == VAR_DECL && DECL_BASED_ON_RESTRICT_P (u))
+	u = DECL_GET_RESTRICT_BASE (u);
+      if (u && TYPE_RESTRICT (TREE_TYPE (u)))
+	{
+	  if (DECL_BASED_ON_RESTRICT_P (t))
+	    gcc_assert (u == DECL_GET_RESTRICT_BASE (t));
+	  else
+	    {
+	      DECL_BASED_ON_RESTRICT_P (t) = 1;
+	      SET_DECL_RESTRICT_BASE (t, u);
+	    }
+	}
+    }
+
   if (TREE_CODE (TREE_TYPE (t)) == COMPLEX_TYPE)
     DECL_COMPLEX_GIMPLE_REG_P (t) = 1;
 
diff --git a/gcc/tree.c b/gcc/tree.c
index 9c4b29c..f7f6503 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -144,6 +144,9 @@ static GTY ((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
 static GTY ((if_marked ("tree_int_map_marked_p"), param_is (struct tree_int_map)))
   htab_t init_priority_for_decl;
 
+static GTY ((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
+  htab_t restrict_base_for_decl;
+
 struct tree_int_map GTY(())
 {
   tree from;
@@ -187,6 +190,8 @@ init_ttree (void)
 					 tree_map_eq, 0);
   init_priority_for_decl = htab_create_ggc (512, tree_int_map_hash,
 					    tree_int_map_eq, 0);
+  restrict_base_for_decl = htab_create_ggc (256, tree_map_hash,
+					    tree_map_eq, 0);
 
   int_cst_hash_table = htab_create_ggc (1024, int_cst_hash_hash,
 					int_cst_hash_eq, NULL);
@@ -568,7 +573,11 @@ copy_node_stat (tree node MEM_STAT_DECL)
 	  SET_DECL_INIT_PRIORITY (t, DECL_INIT_PRIORITY (node));
 	  DECL_HAS_INIT_PRIORITY_P (t) = 1;
 	}
-      
+      if (TREE_CODE (node) == VAR_DECL && DECL_BASED_ON_RESTRICT_P (node))
+	{
+	  SET_DECL_RESTRICT_BASE (t, DECL_GET_RESTRICT_BASE (node));
+	  DECL_BASED_ON_RESTRICT_P (t) = 1;
+	}
     }
   else if (TREE_CODE_CLASS (code) == tcc_type)
     {
@@ -3777,6 +3786,36 @@ decl_init_priority_insert (tree from, unsigned short to)
   *(struct tree_int_map **) loc = h;
 }  
 
+/* Look up a restrict qualified base decl for FROM.  */
+
+tree
+decl_restrict_base_lookup (tree from)
+{
+  struct tree_map *h;
+  struct tree_map in;
+
+  in.from = from;
+  h = htab_find_with_hash (restrict_base_for_decl, &in,
+			   htab_hash_pointer (from));
+  return h ? h->to : NULL_TREE;
+}
+
+/* Record the restrict qualified base TO for FROM.  */
+
+void
+decl_restrict_base_insert (tree from, tree to)
+{
+  struct tree_map *h;
+  void **loc;
+
+  h = ggc_alloc (sizeof (struct tree_map));
+  h->hash = htab_hash_pointer (from);
+  h->from = from;
+  h->to = to;
+  loc = htab_find_slot_with_hash (restrict_base_for_decl, h, h->hash, INSERT);
+  *(struct tree_map **) loc = h;
+}
+
 /* Print out the statistics for the DECL_DEBUG_EXPR hash table.  */
 
 static void
@@ -3798,6 +3837,21 @@ print_value_expr_statistics (void)
 	   (long) htab_elements (value_expr_for_decl),
 	   htab_collisions (value_expr_for_decl));
 }
+
+/* Print out statistics for the RESTRICT_BASE_FOR_DECL hash table, but
+   don't print anything if the table is empty.  */
+
+static void
+print_restrict_base_statistics (void)
+{
+  if (htab_elements (restrict_base_for_decl) != 0)
+    fprintf (stderr,
+	     "RESTRICT_BASE    hash: size %ld, %ld elements, %f collisions\n",
+	     (long) htab_size (restrict_base_for_decl),
+	     (long) htab_elements (restrict_base_for_decl),
+	     htab_collisions (restrict_base_for_decl));
+}
+
 /* Lookup a debug expression for FROM, and return it if we find one.  */
 
 tree 
@@ -5725,6 +5779,7 @@ dump_tree_statistics (void)
   print_type_hash_statistics ();
   print_debug_expr_statistics ();
   print_value_expr_statistics ();
+  print_restrict_base_statistics ();
   lang_hooks.print_statistics ();
 }
 
diff --git a/gcc/tree.h b/gcc/tree.h
index 198c443..08f33fe 100644
--- a/gcc/tree.h
+++ b/gcc/tree.h
@@ -2425,6 +2425,20 @@ struct tree_parm_decl GTY(())
    an address constant.  */
 #define DECL_NON_ADDR_CONST_P(NODE) (DECL_WITH_VIS_CHECK (NODE)->decl_with_vis.non_addr_const_p)
 
+/* DECL_BASED_ON_RESTRICT_P records whether a VAR_DECL is a temporary
+   based on a variable with a restrict qualified type.  If it is,
+   DECL_RESTRICT_BASE returns the restrict qualified variable on which
+   it is based.  */
+
+#define DECL_BASED_ON_RESTRICT_P(NODE) \
+  (VAR_DECL_CHECK (NODE)->decl_with_vis.based_on_restrict_p)
+#define DECL_GET_RESTRICT_BASE(NODE) \
+  (decl_restrict_base_lookup (VAR_DECL_CHECK (NODE)))
+#define SET_DECL_RESTRICT_BASE(NODE, VAL) \
+  (decl_restrict_base_insert (VAR_DECL_CHECK (NODE), (VAL)))
+
+extern tree decl_restrict_base_lookup (tree);
+extern void decl_restrict_base_insert (tree, tree);
 
 /* Used in a DECL to indicate that, even if it TREE_PUBLIC, it need
    not be put out unless it is needed in this translation unit.
@@ -2500,7 +2514,8 @@ struct tree_decl_with_vis GTY(())
  unsigned common_flag:1; 
  unsigned in_text_section : 1;
  unsigned gimple_formal_temp : 1;
- unsigned non_addr_const_p : 1; 
+ unsigned non_addr_const_p : 1;
+ unsigned based_on_restrict_p : 1;
  /* Used by C++.  Might become a generic decl flag.  */
  unsigned shadowed_for_var_p : 1;
  
@@ -2517,7 +2532,7 @@ struct tree_decl_with_vis GTY(())
 
  /* Belongs to VAR_DECL exclusively.  */
  ENUM_BITFIELD(tls_model) tls_model : 3;
- /* 13 unused bits. */
+ /* 11 unused bits. */
 };
 
 /* In a VAR_DECL that's static,