re PR middle-end/14187 ([tree-ssa] C restricted pointers are not properly implemented)

2009-06-29  Richard Guenther  <rguenther@suse.de>

	PR middle-end/14187
	* tree-ssa-alias.h (struct pt_solution): Add vars_contains_restrict
	flag.
	(pt_solutions_same_restrict_base): Declare.
	* tree-ssa-structalias.c (struct variable_info): Add is_restrict_var
	flag.
	(new_var_info): Initialize is_global_var properly for SSA_NAMEs.
	(make_constraint_from, make_copy_constraint): Move earlier.
	(make_constraint_from_heapvar): New function.
	(make_constraint_from_restrict): Likewise.
	(handle_lhs_call): Use it.
	(find_func_aliases): Use it to track conversions to restrict
	qualified pointers.
	(struct fieldoff): Add only_restrict_pointers flag.
	(push_fields_onto_fieldstack): Initialize it.
	(create_variable_info_for): Track global restrict qualified pointers.
	(intra_create_variable_infos): Use make_constraint_from_heapvar.
	Track restrict qualified pointer arguments.
	(set_uids_in_ptset): Use varinfo is_global_var flag.
	(find_what_var_points_to): Set the vars_contains_restrict flag.
	Always create the points-to solution for sets including restrict tags.
	(pt_solutions_same_restrict_base): New function.
	* tree-ssa-alias.c (ptr_derefs_may_alias_p): For two restrict
	qualified pointers use pt_solutions_same_restrict_base as
	additional source for disambiguation.

	* gcc.dg/tree-ssa/restrict-1.c: New testcase.
	* gcc.dg/tree-ssa/restrict-2.c: Likewise.
	* gcc.dg/tree-ssa/restrict-3.c: Likewise.
	* gcc.c-torture/execute/20090623-1.c: Likewise.
	* gcc.dg/tree-ssa/ldist-13.c: Likewise.
	* gcc.dg/tree-ssa/ldist-14.c: Likewise.

From-SVN: r149048

gcc/ChangeLog

 2009-06-29  Richard Guenther  <rguenther@suse.de>
 
+	PR middle-end/14187
+	* tree-ssa-alias.h (struct pt_solution): Add vars_contains_restrict
+	flag.
+	(pt_solutions_same_restrict_base): Declare.
+	* tree-ssa-structalias.c (struct variable_info): Add is_restrict_var
+	flag.
+	(new_var_info): Initialize is_global_var properly for SSA_NAMEs.
+	(make_constraint_from, make_copy_constraint): Move earlier.
+	(make_constraint_from_heapvar): New function.
+	(make_constraint_from_restrict): Likewise.
+	(handle_lhs_call): Use it.
+	(find_func_aliases): Use it to track conversions to restrict
+	qualified pointers.
+	(struct fieldoff): Add only_restrict_pointers flag.
+	(push_fields_onto_fieldstack): Initialize it.
+	(create_variable_info_for): Track global restrict qualified pointers.
+	(intra_create_variable_infos): Use make_constraint_from_heapvar.
+	Track restrict qualified pointer arguments.
+	(set_uids_in_ptset): Use varinfo is_global_var flag.
+	(find_what_var_points_to): Set the vars_contains_restrict flag.
+	Always create the points-to solution for sets including restrict tags.
+	(pt_solutions_same_restrict_base): New function.
+	* tree-ssa-alias.c (ptr_derefs_may_alias_p): For two restrict
+	qualified pointers use pt_solutions_same_restrict_base as
+	additional source for disambiguation.
+
+2009-06-29  Richard Guenther  <rguenther@suse.de>
+
 	PR middle-end/38212
 	* alias.c (find_base_decl): Remove.
 	(get_deref_alias_set_1): Remove restrict handling.

gcc/testsuite/ChangeLog

 2009-06-29  Richard Guenther  <rguenther@suse.de>
 
+	PR middle-end/14187
+	* gcc.dg/tree-ssa/restrict-1.c: New testcase.
+	* gcc.dg/tree-ssa/restrict-2.c: Likewise.
+	* gcc.dg/tree-ssa/restrict-3.c: Likewise.
+	* gcc.c-torture/execute/20090623-1.c: Likewise.
+	* gcc.dg/tree-ssa/ldist-13.c: Likewise.
+	* gcc.dg/tree-ssa/ldist-14.c: Likewise.
+
+2009-06-29  Richard Guenther  <rguenther@suse.de>
+
 	PR middle-end/38212
 	* gcc.c-torture/execute/pr38212.c: New testcase.
 

gcc/testsuite/gcc.c-torture/execute/20090623-1.c

+int * __restrict__ x;
+
+int foo (int y)
+{
+  *x = y;
+  return *x;
+}
+
+extern void abort (void);
+
+int main()
+{
+  int i = 0;
+  x = &i;
+  if (foo(1) != 1)
+    abort ();
+  return 0;
+}

gcc/testsuite/gcc.dg/tree-ssa/ldist-13.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -ftree-loop-distribution -fdump-tree-ldist-details" } */
+
+float * __restrict__ x;
+float * __restrict__ y;
+
+float foo (int n)
+{
+  int i;
+  float tmp = 0.0;
+  for (i = 0; i < n; ++i)
+    {
+      x[i] = 0.0;
+      tmp += y[i];
+    }
+  return tmp;
+}
+
+/* We should apply loop distribution.  */
+
+/* { dg-final { scan-tree-dump "Loop 1 distributed: split to 2 loops" "ldist" } } */
+/* { dg-final { cleanup-tree-dump "ldist" } } */

gcc/testsuite/gcc.dg/tree-ssa/ldist-14.c

+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-strict-aliasing -ftree-loop-distribution -fdump-tree-ldist-details" } */
+
+struct desc {
+  int i;
+  void * __restrict__ data;
+  int j;
+} a, b;
+
+float foo (int n)
+{
+  int i;
+  float * __restrict__ x, * __restrict__ y, tmp = 0.0;
+  x = (float * __restrict__)a.data;
+  y = (float * __restrict__)b.data;
+  for (i = 0; i < n; ++i)
+    {
+      x[i] = 0.0;
+      tmp += y[i];
+    }
+  return tmp;
+}
+
+/* We should apply loop distribution.  */
+
+/* { dg-final { scan-tree-dump "Loop 1 distributed: split to 2 loops" "ldist" } } */
+/* { dg-final { cleanup-tree-dump "ldist" } } */

gcc/testsuite/gcc.dg/tree-ssa/restrict-1.c

+/* { dg-do link } */
+/* { dg-options "-O -fno-strict-aliasing -fdump-tree-optimized" } */
+
+extern void link_error (void);
+
+void bar0 (int * __restrict__ arr1, int * __restrict__ arr2)
+{
+  arr1[0] = 1;
+  arr2[0] = 1;
+  if (arr1[0] != 1)
+    link_error ();
+}
+
+int main()
+{
+  return 0;
+}
+
+/* { dg-final { scan-tree-dump-not "link_error" "optimized" } } */
+/* { dg-final { cleanup-tree-dump "optimized" } } */

gcc/testsuite/gcc.dg/tree-ssa/restrict-2.c

+/* { dg-do compile } */
+/* { dg-options "-O -fno-strict-aliasing -fdump-tree-lim-details" } */
+
+void foo (float * __restrict__ a, float * __restrict__ b, int n, int j)
+{
+  int i;
+  for(i = 0; i < n; ++i)
+    a[i] = (b[j+50] + b[j-50]) * 0.5f;
+}
+
+/* We should move the RHS of the store out of the loop.  */
+
+/* { dg-final { scan-tree-dump-times "Moving statement" 11 "lim" } } */
+/* { dg-final { cleanup-tree-dump "lim" } } */

gcc/testsuite/gcc.dg/tree-ssa/restrict-3.c

+/* { dg-do compile } */
+/* { dg-options "-O -fno-strict-aliasing -fdump-tree-lim-details" } */
+
+void f(int * __restrict__ r,
+       int a[__restrict__ 16][16],
+       int b[__restrict__ 16][16],
+       int i, int j)
+{
+  int x;
+  *r = 0;
+  for (x = 1; x < 16; ++x)
+    *r = *r + a[i][x] * b[x][j];
+}
+
+/* We should apply store motion to the store to *r.  */
+
+/* { dg-final { scan-tree-dump "Executing store motion of \\\*r" "lim" } } */
+/* { dg-final { cleanup-tree-dump "lim" } } */

gcc/tree-ssa-alias.c

@@ -273,6 +273,13 @@ ptr_derefs_may_alias_p (tree ptr1, tree ptr2)
   if (!pi1 || !pi2)
     return true;
 
+  /* If both pointers are restrict-qualified try to disambiguate
+     with restrict information.  */
+  if (TYPE_RESTRICT (TREE_TYPE (ptr1))
+      && TYPE_RESTRICT (TREE_TYPE (ptr2))
+      && !pt_solutions_same_restrict_base (&pi1->pt, &pi2->pt))
+    return false;
+
   /* ???  This does not use TBAA to prune decls from the intersection
      that not both pointers may access.  */
   return pt_solutions_intersect (&pi1->pt, &pi2->pt);

gcc/tree-ssa-alias.h

@@ -49,6 +49,9 @@ struct GTY(()) pt_solution
   /* Nonzero if the pt_vars bitmap includes a global variable.  */
   unsigned int vars_contains_global : 1;
 
+  /* Nonzero if the pt_vars bitmap includes a restrict tag variable.  */
+  unsigned int vars_contains_restrict : 1;
+
   /* Set of variables that this pointer may point to.  */
   bitmap vars;
 };
@@ -115,6 +118,8 @@ extern void delete_alias_heapvars (void);
 extern bool pt_solution_includes_global (struct pt_solution *);
 extern bool pt_solution_includes (struct pt_solution *, const_tree);
 extern bool pt_solutions_intersect (struct pt_solution *, struct pt_solution *);
+extern bool pt_solutions_same_restrict_base (struct pt_solution *,
+					     struct pt_solution *);
 extern void pt_solution_reset (struct pt_solution *);
 extern void dump_pta_stats (FILE *);