gcc/testsuite/gcc.dg/tree-ssa/vrp83.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-O2 -fdump-tree-vrp1" } */
   3
   4 extern void vrp_keep (void);
   5
   6 void
   7 f2 (int c, int b)
   8 {
   9   int s = 0;
  10   if (c == 0)
  11     s += 1;
  12   else if (c < 1)
  13     s -= 1;
  14   /* s in [-1, 1].   */
  15   b = (b & 1) + 1;
  16   /* b in range [1, 2].  */
  17   b = s << b;
  18   /* b in range [-4, 4].  */
  19   if (b == -4)
  20     vrp_keep ();
  21   if (b == 4)
  22     vrp_keep ();
  23 }
  24
  25 void
  26 f3 (int s, int b)
  27 {
  28   if (s >> 3 == -2)
  29     {
  30       /* s in range [-16, -9].  */
  31       b = (b & 1) + 1;
  32       /* b in range [1, 2].  */
  33       b =  s << b;
  34       /* b in range [bmin << smax, bmax << smin],
  35                     == [-16 << 2, -9 << 1]
  36                     == [-64, -18].  */
  37       if (b == -64)
  38         vrp_keep ();
  39       if (b == -18)
  40         vrp_keep ();
  41     }
  42 }
  43
  44 void
  45 f4 (unsigned int s, unsigned int b)
  46 {
  47   s |= ~(0xffU);
  48   /* s in [0xffffff00, 0xffffffff].  */
  49   b = (b & 1) + 1;
  50   /* b in [1, 2].  */
  51   b = s << b;
  52   /* s in [0xfffffc00, 0xfffffffe].  */
  53   if (b == ~0x3ffU)
  54     vrp_keep ();
  55   if (b == ~0x1U)
  56     vrp_keep ();
  57 }
  58
  59 /* { dg-final { scan-tree-dump-times "vrp_keep \\(" 6 "vrp1"} } */