Handle recursive restrict in function parameter

2015-11-04  Tom de Vries  <tom@codesourcery.com>

	PR tree-optimization/67742
	* tree-ssa-structalias.c (struct fieldoff): Add restrict_pointed_type
	field.
	(push_fields_onto_fieldstack): Handle restrict_pointed_type field.
	(create_variable_info_for_1): Add and handle handle_param parameter.
	Add restrict handling.
	(create_variable_info_for): Call create_variable_info_for_1 with extra
	arg.
	(make_param_constraints): Drop restrict_name parameter.  Ignore
	vi->only_restrict_pointers.
	(intra_create_variable_infos): Call create_variable_info_for_1 with
	extra arg.  Remove restrict handling.  Call make_param_constraints with
	one less arg.

	* gcc.dg/tree-ssa/restrict-7.c: New test.
	* gcc.dg/tree-ssa/restrict-8.c: New test.

From-SVN: r229755

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 9b82fc2ac96f846c3fd82117cb8e10aa87153414..9304d780e2974aa3576750d62f9881cfec87af99 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,19 @@
+2015-11-04  Tom de Vries  <tom@codesourcery.com>
+
+       PR tree-optimization/67742
+       * tree-ssa-structalias.c (struct fieldoff): Add restrict_pointed_type
+       field.
+       (push_fields_onto_fieldstack): Handle restrict_pointed_type field.
+       (create_variable_info_for_1): Add and handle handle_param parameter.
+       Add restrict handling.
+       (create_variable_info_for): Call create_variable_info_for_1 with extra
+       arg.
+       (make_param_constraints): Drop restrict_name parameter.  Ignore
+       vi->only_restrict_pointers.
+       (intra_create_variable_infos): Call create_variable_info_for_1 with
+       extra arg.  Remove restrict handling.  Call make_param_constraints with
+       one less arg.
+
 2015-11-04  Tom de Vries  <tom@codesourcery.com>
 
        * tree-ssa-structalias.c (create_variable_info_for_1): Use decl_type

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 43bb7204ec4208eef7d9d3d38a698227c39b26cd..d99f0fc28441838532bc2b03de9864c307e01fd5 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,9 @@
+2015-11-04  Tom de Vries  <tom@codesourcery.com>
+
+       PR tree-optimization/67742
+       * gcc.dg/tree-ssa/restrict-7.c: New test.
+       * gcc.dg/tree-ssa/restrict-8.c: New test.
+
 2015-11-04  Eric Botcazou  <ebotcazou@adacore.com>
 
        * gnat.dg/slice9.adb: New test.

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/restrict-7.c b/gcc/testsuite/gcc.dg/tree-ssa/restrict-7.c
new file mode 100644 (file)
index 0000000..f7a68c7
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/restrict-7.c
@@ -0,0 +1,12 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-fre1" } */
+
+int
+f (int *__restrict__ *__restrict__ *__restrict__ a, int *b)
+{
+  *b = 1;
+  ***a  = 2;
+  return *b;
+}
+
+/* { dg-final { scan-tree-dump-times "return 1" 1 "fre1" } } */

diff --git a/gcc/testsuite/gcc.dg/tree-ssa/restrict-8.c b/gcc/testsuite/gcc.dg/tree-ssa/restrict-8.c
new file mode 100644 (file)
index 0000000..b0ab164
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/tree-ssa/restrict-8.c
@@ -0,0 +1,17 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fdump-tree-fre1" } */
+
+struct s
+{
+  int *__restrict__ *__restrict__ pp;
+};
+
+int
+f (struct s s, int *b)
+{
+  *b = 1;
+  **s.pp = 2;
+  return *b;
+}
+
+/* { dg-final { scan-tree-dump-times "return 1" 1 "fre1" } } */

diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c
index 98b5f168032e3a2b7332ed7906f84dcc2053a9dc..52a35f6ab510de9b256f1e6d667d10ee2c10fa0d 100644 (file)
--- a/gcc/tree-ssa-structalias.c
+++ b/gcc/tree-ssa-structalias.c
@@ -307,6 +307,7 @@ static varinfo_t first_or_preceding_vi_for_offset (varinfo_t,
                                                   unsigned HOST_WIDE_INT);
 static varinfo_t lookup_vi_for_tree (tree);
 static inline bool type_can_have_subvars (const_tree);
+static void make_param_constraints (varinfo_t);
 
 /* Pool of variable info structures.  */
 static object_allocator<variable_info> variable_info_pool
@@ -393,7 +394,6 @@ new_var_info (tree t, const char *name, bool add_id)
   return ret;
 }
 
-
 /* A map mapping call statements to per-stmt variables for uses
    and clobbers specific to the call.  */
 static hash_map<gimple *, varinfo_t> *call_stmt_vars;
@@ -5195,6 +5195,8 @@ struct fieldoff
   unsigned may_have_pointers : 1;
 
   unsigned only_restrict_pointers : 1;
+
+  tree restrict_pointed_type;
 };
 typedef struct fieldoff fieldoff_s;
 
@@ -5340,7 +5342,8 @@ push_fields_onto_fieldstack (tree type, vec<fieldoff_s> *fieldstack,
            if (!pair
                && offset + foff != 0)
              {
-               fieldoff_s e = {0, offset + foff, false, false, false, false};
+               fieldoff_s e
+                 = {0, offset + foff, false, false, false, false, NULL_TREE};
                pair = fieldstack->safe_push (e);
              }
 
@@ -5374,6 +5377,8 @@ push_fields_onto_fieldstack (tree type, vec<fieldoff_s> *fieldstack,
                  = (!has_unknown_size
                     && POINTER_TYPE_P (field_type)
                     && TYPE_RESTRICT (field_type));
+               if (e.only_restrict_pointers)
+                 e.restrict_pointed_type = TREE_TYPE (field_type);
                fieldstack->safe_push (e);
              }
          }
@@ -5642,10 +5647,11 @@ 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, bool add_id)
+create_variable_info_for_1 (tree decl, const char *name, bool add_id,
+                           bool handle_param)
 {
   varinfo_t vi, newvi;
   tree decl_type = TREE_TYPE (decl);
@@ -5721,6 +5727,20 @@ create_variable_info_for_1 (tree decl, const char *name, bool add_id)
       if (POINTER_TYPE_P (decl_type)
          && TYPE_RESTRICT (decl_type))
        vi->only_restrict_pointers = 1;
+      if (vi->only_restrict_pointers
+         && !type_contains_placeholder_p (TREE_TYPE (decl_type))
+         && 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", true,
+                                           true);
+         rvi->is_restrict_var = 1;
+         insert_vi_for_tree (heapvar, rvi);
+         make_constraint_from (vi, rvi->id);
+         make_param_constraints (rvi);
+       }
       fieldstack.release ();
       return vi;
     }
@@ -5758,6 +5778,20 @@ create_variable_info_for_1 (tree decl, const char *name, bool add_id)
       newvi->fullsize = vi->fullsize;
       newvi->may_have_pointers = fo->may_have_pointers;
       newvi->only_restrict_pointers = fo->only_restrict_pointers;
+      if (handle_param
+         && newvi->only_restrict_pointers
+         && !type_contains_placeholder_p (fo->restrict_pointed_type))
+       {
+         varinfo_t rvi;
+         tree heapvar = build_fake_var_decl (fo->restrict_pointed_type);
+         DECL_EXTERNAL (heapvar) = 1;
+         rvi = create_variable_info_for_1 (heapvar, "PARM_NOALIAS", true,
+                                           true);
+         rvi->is_restrict_var = 1;
+         insert_vi_for_tree (heapvar, rvi);
+         make_constraint_from (newvi, rvi->id);
+         make_param_constraints (rvi);
+       }
       if (i + 1 < fieldstack.length ())
        {
          varinfo_t tem = new_var_info (decl, name, false);
@@ -5772,7 +5806,7 @@ create_variable_info_for_1 (tree decl, const char *name, bool add_id)
 static unsigned int
 create_variable_info_for (tree decl, const char *name, bool add_id)
 {
-  varinfo_t vi = create_variable_info_for_1 (decl, name, add_id);
+  varinfo_t vi = create_variable_info_for_1 (decl, name, add_id, false);
   unsigned int id = vi->id;
 
   insert_vi_for_tree (decl, vi);
@@ -5879,16 +5913,15 @@ debug_solution_for_var (unsigned int var)
   dump_solution_for_var (stderr, var);
 }
 
-/* Register the constraints for function parameter related VI.  Use RESTRICT_NAME
-   as the base name of created restrict vars.  */
+/* Register the constraints for function parameter related VI.  */
 
 static void
-make_param_constraints (varinfo_t vi, const char *restrict_name)
+make_param_constraints (varinfo_t vi)
 {
   for (; vi; vi = vi_next (vi))
     {
       if (vi->only_restrict_pointers)
-       make_constraint_from_global_restrict (vi, restrict_name, true);
+       ;
       else if (vi->may_have_pointers)
        make_constraint_from (vi, nonlocal_id);
 
@@ -5910,32 +5943,11 @@ intra_create_variable_infos (struct function *fn)
      passed-by-reference argument.  */
   for (t = DECL_ARGUMENTS (fn->decl); t; t = DECL_CHAIN (t))
     {
-      bool restrict_pointer_p = (POINTER_TYPE_P (TREE_TYPE (t))
-                                && TYPE_RESTRICT (TREE_TYPE (t)));
-      bool recursive_restrict_p
-       = (restrict_pointer_p
-          && !type_contains_placeholder_p (TREE_TYPE (TREE_TYPE (t))));
-      varinfo_t p = create_variable_info_for_1 (t, alias_get_name (t), false);
+      varinfo_t p
+       = create_variable_info_for_1 (t, alias_get_name (t), false, true);
       insert_vi_for_tree (t, p);
 
-      /* For restrict qualified pointers build a representative for
-        the pointed-to object.  Note that this ends up handling
-        out-of-bound references conservatively by aggregating them
-        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", true);
-         vi->is_restrict_var = 1;
-         insert_vi_for_tree (heapvar, vi);
-         make_constraint_from (p, vi->id);
-         make_param_constraints (vi, "GLOBAL_RESTRICT");
-         continue;
-       }
-
-      make_param_constraints (p, "PARM_RESTRICT");
+      make_param_constraints (p);
     }
 
   /* Add a constraint for a result decl that is passed by reference.  */