[PATCH, 1/2] Add handle_param parameter to create_variable_info_for_1

[Tom de Vries <Tom_deVries at mentor dot com>]

Hi,

this no-functional-changes patch copies the restrict var declaration 
code from intra_create_variable_infos to create_variable_info_for_1.

The code was copied rather than moved, since in fipa-pta mode the 
varinfo p for the parameter t may already exist due to 
create_function_info_for, in which case we're not calling 
create_variable_info_for_1 to set p, meaning the copied code won't get 
triggered.

Bootstrapped and reg-tested on x86_64.

OK for trunk?

Thanks,
- Tom

Add handle_param parameter to create_variable_info_for_1

2015-10-26  Tom de Vries  <tom@codesourcery.com>

	* tree-ssa-structalias.c (struct variable_info): Add
	restrict_pointed_var field.
	(create_variable_info_for_1): Add and handle handle_param parameter.
	(create_variable_info_for): Call create_variable_info_for_1 with extra
	arg.
	(intra_create_variable_infos): Same.  Handle case that
	p->restrict_pointed_var is unequal zero.
---
 gcc/tree-ssa-structalias.c | 40 ++++++++++++++++++++++++++++++----------
 1 file changed, 30 insertions(+), 10 deletions(-)

diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index 63a3d02..3fdad3a 100644
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -272,6 +272,9 @@ struct variable_info
   /* True if this field has only restrict qualified pointers.  */
   unsigned int only_restrict_pointers : 1;
 
+  /* The id of the pointed-to restrict var in case only_restrict_pointers.  */
+  unsigned int restrict_pointed_var;
+
   /* True if this represents a heap var created for a restrict qualified
      pointer.  */
   unsigned int is_restrict_var : 1;
@@ -5608,10 +5611,10 @@ check_for_overlaps (vec<fieldoff_s> fieldstack)
 
 /* Create a varinfo structure for NAME and DECL, and add it to VARMAP.
    This will also create any varinfo structures necessary for fields
-   of DECL.  */
+   of DECL.  DECL is a function parameter if HANDLE_PARAM is set.  */
 
 static varinfo_t
-create_variable_info_for_1 (tree decl, const char *name)
+create_variable_info_for_1 (tree decl, const char *name, bool handle_param)
 {
   varinfo_t vi, newvi;
   tree decl_type = TREE_TYPE (decl);
@@ -5687,6 +5690,17 @@ create_variable_info_for_1 (tree decl, const char *name)
       if (POINTER_TYPE_P (TREE_TYPE (decl))
 	  && TYPE_RESTRICT (TREE_TYPE (decl)))
 	vi->only_restrict_pointers = 1;
+      if (vi->only_restrict_pointers
+	  && handle_param)
+	{
+	  varinfo_t rvi;
+	  tree heapvar = build_fake_var_decl (TREE_TYPE (decl_type));
+	  DECL_EXTERNAL (heapvar) = 1;
+	  rvi = create_variable_info_for_1 (heapvar, "PARM_NOALIAS", false);
+	  rvi->is_restrict_var = 1;
+	  insert_vi_for_tree (heapvar, rvi);
+	  vi->restrict_pointed_var = rvi->id;
+	}
       fieldstack.release ();
       return vi;
     }
@@ -5738,7 +5752,7 @@ create_variable_info_for_1 (tree decl, const char *name)
 static unsigned int
 create_variable_info_for (tree decl, const char *name)
 {
-  varinfo_t vi = create_variable_info_for_1 (decl, name);
+  varinfo_t vi = create_variable_info_for_1 (decl, name, false);
   unsigned int id = vi->id;
 
   insert_vi_for_tree (decl, vi);
@@ -5880,7 +5894,8 @@ intra_create_variable_infos (struct function *fn)
       varinfo_t p = lookup_vi_for_tree (t);
       if (p == NULL)
 	{
-	  p = create_variable_info_for_1 (t, alias_get_name (t));
+	  p = create_variable_info_for_1 (t, alias_get_name (t),
+					  recursive_restrict_p);
 	  insert_vi_for_tree (t, p);
 	}
 
@@ -5890,12 +5905,17 @@ intra_create_variable_infos (struct function *fn)
 	 in the first/last subfield of the object.  */
       if (recursive_restrict_p)
 	{
-	  varinfo_t vi;
-	  tree heapvar = build_fake_var_decl (TREE_TYPE (TREE_TYPE (t)));
-	  DECL_EXTERNAL (heapvar) = 1;
-	  vi = create_variable_info_for_1 (heapvar, "PARM_NOALIAS");
-	  vi->is_restrict_var = 1;
-	  insert_vi_for_tree (heapvar, vi);
+	  varinfo_t vi = get_varinfo (p->restrict_pointed_var);
+	  if (vi == NULL)
+	    {
+	      tree heapvar = build_fake_var_decl (TREE_TYPE (TREE_TYPE (t)));
+	      DECL_EXTERNAL (heapvar) = 1;
+	      vi = create_variable_info_for_1 (heapvar, "PARM_NOALIAS", false);
+	      vi->is_restrict_var = 1;
+	      insert_vi_for_tree (heapvar, vi);
+	      p->restrict_pointed_var = vi->id;
+	      p->only_restrict_pointers = 1;
+	    }
 	  make_constraint_from (p, vi->id);
 	  make_restrict_var_constraints (vi);
 	  continue;
-- 
1.9.1