1extern void abort();
2
3#define HOST_WIDE_INT long
4#define HOST_BITS_PER_WIDE_INT (sizeof(long)*8)
5
6struct tree_type
7{
8  unsigned int precision : 9;
9};
10
11int
12sign_bit_p (struct tree_type *t, HOST_WIDE_INT val_hi, unsigned HOST_WIDE_INT val_lo)
13{
14  unsigned HOST_WIDE_INT mask_lo, lo;
15  HOST_WIDE_INT mask_hi, hi;
16  int width = t->precision;
17
18  if (width > HOST_BITS_PER_WIDE_INT)
19    {
20      hi = (unsigned HOST_WIDE_INT) 1 << (width - HOST_BITS_PER_WIDE_INT - 1);
21      lo = 0;
22
23      mask_hi = ((unsigned HOST_WIDE_INT) -1
24                 >> (2 * HOST_BITS_PER_WIDE_INT - width));
25      mask_lo = -1;
26    }
27  else
28    {
29      hi = 0;
30      lo = (unsigned HOST_WIDE_INT) 1 << (width - 1);
31
32      mask_hi = 0;
33      mask_lo = ((unsigned HOST_WIDE_INT) -1
34                 >> (HOST_BITS_PER_WIDE_INT - width));
35    }
36
37  if ((val_hi & mask_hi) == hi
38      && (val_lo & mask_lo) == lo)
39    return 1;
40
41  return 0;
42}
43
44int main()
45{
46  struct tree_type t;
47  t.precision = 1;
48  if (!sign_bit_p (&t, 0, -1))
49    abort ();
50  return 0;
51}
52