gcc/testsuite/gcc.dg/recip_sqrt_mult_5.c

   1 /* { dg-do compile } */
   2 /* { dg-options "-Ofast -fdump-tree-recip" } */
   3
   4 /* We want to do the recip_sqrt transformations here there is already
   5    a multiplication on the main path.  */
   6
   7 double res, res2, tmp;
   8 void
   9 foo (double a, double b, int c, int d)
  10 {
  11   tmp = 1.0 / __builtin_sqrt (a);
  12   res = tmp * tmp;
  13
  14   if (d)
  15     res2 = a * tmp;
  16 }
  17
  18 /* { dg-final { scan-tree-dump "Optimizing reciprocal sqrt multiplications" "recip" } } */
  19 /* { dg-final { scan-tree-dump "Replacing squaring multiplication" "recip" } } */
  20 /* { dg-final { scan-tree-dump "Replacing original division" "recip" } } */