gcc/testsuite/gcc.dg/pr18241-2.c

   1 /* { dg-do run } */
   2 /* { dg-options "-std=gnu99 -Wall -Wextra -O1" } */
   3
   4 extern void *memset (void*, int, unsigned long);
   5 extern void abort (void);
   6
   7 struct radix_tree_root {
   8         unsigned int height;
   9         struct radix_tree_node *rnode;
  10 };
  11
  12 struct radix_tree_node {
  13         unsigned int count;
  14         void *slots[64];
  15         unsigned long tags[2];
  16 };
  17
  18 struct radix_tree_path {
  19         struct radix_tree_node *node, **slot;
  20         int offset;
  21 };
  22
  23 void radix_tree_tag_clear(struct radix_tree_root *root, unsigned long index)
  24 {
  25         struct radix_tree_path path[7], *pathp = path;
  26         unsigned int height, shift;
  27         volatile unsigned long *addr;
  28
  29         height = root->height;
  30
  31         shift = (height - 1) * 6;
  32         path[0].slot = &root->rnode;
  33
  34         while (height > 0) {
  35                 int offset;
  36
  37                 offset = (index >> shift) & (64-1);
  38                 pathp[1].offset = offset;
  39                 pathp[1].node = *pathp[0].slot;
  40                 pathp[1].slot = (struct radix_tree_node **)
  41                         (pathp[1].node->slots + offset);
  42                 pathp++;
  43                 shift -= 6;
  44                 height--;
  45         }
  46
  47         addr = &(pathp->node->tags[0]) + 1;
  48         *addr = 574;
  49 }
  50
  51 struct radix_tree_root r;
  52 struct radix_tree_node node;
  53
  54 int main ()
  55 {
  56         r.height = 1;
  57         r.rnode = &node;
  58
  59         memset (&node, 0, sizeof (node));
  60
  61         node.count = 1;
  62
  63         radix_tree_tag_clear (&r, 13);
  64         return 0;
  65 }