[PATCH] Fix recent regression in tree-object-size.c (PR tree-optimization/59362)

[Jakub Jelinek]

Hi!

Recent change to tree-object-size.c to fold stmts with immediate uses
of __builtin_object_size result broke the pass, because it now can
create new SSA_NAMEs and the code wasn't expecting that to happen.

Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux,
ok for trunk?

2013-12-02  Jakub Jelinek  <ja...@redhat.com>

        PR tree-optimization/59362
        * tree-object-size.c (object_sizes): Change into array of
        vec<unsigned HOST_WIDE_INT>.
        (compute_builtin_object_size): Check computed bitmap for
        non-NULL instead of object_sizes.  Call safe_grow on object_sizes
        vector if new SSA_NAMEs appeared.
        (init_object_sizes): Check computed bitmap for non-NULL.
        Call safe_grow on object_sizes elements instead of initializing
        it with XNEWVEC.
        (fini_object_sizes): Call release on object_sizes elements, don't
        set it to NULL.

        * gcc.c-torture/compile/pr59362.c: New test.

--- gcc/tree-object-size.c.jj   2013-11-22 21:03:16.000000000 +0100
+++ gcc/tree-object-size.c      2013-12-02 10:16:01.777024163 +0100
@@ -78,7 +78,7 @@ static void check_for_plus_in_loops_1 (s
    the subobject (innermost array or field with address taken).
    object_sizes[2] is lower bound for number of bytes till the end of
    the object and object_sizes[3] lower bound for subobject.  */
-static unsigned HOST_WIDE_INT *object_sizes[4];
+static vec<unsigned HOST_WIDE_INT> object_sizes[4];
 
 /* Bitmaps what object sizes have been computed already.  */
 static bitmap computed[4];
@@ -506,7 +506,7 @@ compute_builtin_object_size (tree ptr, i
 
   if (TREE_CODE (ptr) == SSA_NAME
       && POINTER_TYPE_P (TREE_TYPE (ptr))
-      && object_sizes[object_size_type] != NULL)
+      && computed[object_size_type] != NULL)
     {
       if (!bitmap_bit_p (computed[object_size_type], SSA_NAME_VERSION (ptr)))
        {
@@ -514,6 +514,8 @@ compute_builtin_object_size (tree ptr, i
          bitmap_iterator bi;
          unsigned int i;
 
+         if (num_ssa_names > object_sizes[object_size_type].length ())
+           object_sizes[object_size_type].safe_grow (num_ssa_names);
          if (dump_file)
            {
              fprintf (dump_file, "Computing %s %sobject size for ",
@@ -1175,12 +1177,12 @@ init_object_sizes (void)
 {
   int object_size_type;
 
-  if (object_sizes[0])
+  if (computed[0])
     return;
 
   for (object_size_type = 0; object_size_type <= 3; object_size_type++)
     {
-      object_sizes[object_size_type] = XNEWVEC (unsigned HOST_WIDE_INT, 
num_ssa_names);
+      object_sizes[object_size_type].safe_grow (num_ssa_names);
       computed[object_size_type] = BITMAP_ALLOC (NULL);
     }
 
@@ -1197,9 +1199,8 @@ fini_object_sizes (void)
 
   for (object_size_type = 0; object_size_type <= 3; object_size_type++)
     {
-      free (object_sizes[object_size_type]);
+      object_sizes[object_size_type].release ();
       BITMAP_FREE (computed[object_size_type]);
-      object_sizes[object_size_type] = NULL;
     }
 }
 
--- gcc/testsuite/gcc.c-torture/compile/pr59362.c.jj    2013-12-02 
10:20:10.964738283 +0100
+++ gcc/testsuite/gcc.c-torture/compile/pr59362.c       2013-12-02 
10:18:19.000000000 +0100
@@ -0,0 +1,21 @@
+/* PR tree-optimization/59362 */
+
+char *
+foo (char *r, int s)
+{
+  r = __builtin___stpcpy_chk (r, "abc", __builtin_object_size (r, 1));
+  if (s)
+    r = __builtin___stpcpy_chk (r, "d", __builtin_object_size (r, 1));
+  return r;
+}
+
+char *a;
+long int b;
+
+void
+bar (void)
+{
+  b = __builtin_object_size (0, 0);
+  a = __builtin___stpcpy_chk (0, "", b);
+  b = __builtin_object_size (a, 0);
+}

        Jakub