gcc/testsuite/gcc.dg/pr102738.c

   1 /* PR tree-optimization/102738 */
   2 /* { dg-options "-O2 -fdump-tree-evrp" } */
   3 /* { dg-do compile { target int128 } } */
   4
   5 /* Remove arithmetic shift right when the LHS is known to be 0 or -1.  */
   6
   7 int a1(__int128 f, int g)
   8 {
   9      /* Leaves f >> 127.  */
  10     return (f >> 127) >> g;
  11 }
  12
  13 int a2(int f, int g)
  14 {
  15      /* Leaves f >> 31.  */
  16     return (f >> 31) >> g;
  17 }
  18
  19 int a3(int f, int g)
  20 {
  21     if (f == 0 || f == -1)
  22       return f >> g;
  23     __builtin_unreachable();
  24 }
  25
  26 int a4(int f, int g)
  27 {
  28     if (f == 0 || f == 1)
  29       return (-f) >> g;
  30     __builtin_unreachable();
  31 }
  32
  33 int a5(int f, int g)
  34 {
  35     if (f == 0 || f == 1)
  36       return (f-1) >> g;
  37     return 0;
  38 }
  39
  40 int a6(int f, int g)
  41 {
  42     if (f == 6 || f == 7)
  43       return (f-7) >> g;
  44     __builtin_unreachable();
  45 }
  46
  47 /* { dg-final { scan-tree-dump-times " >> 127" 1 "evrp" } } */
  48 /* { dg-final { scan-tree-dump-times " >> 31" 1 "evrp" } } */
  49 /* { dg-final { scan-tree-dump-times " >> " 2 "evrp" } } */