gcc/testsuite/gcc.target/powerpc/pr48053-3.c

   1 /* { dg-do compile } */
   2 /* { dg-skip-if "" { powerpc*-*-darwin* } { "*" } { "" } } */
   3 /* { dg-require-effective-target powerpc_vsx_ok } */
   4 /* { dg-options "-O3 -mcpu=power7" } */
   5
   6 /* Cut down example from s_scalbnl that aborted on 32-bit when the fix for
   7    48053 went in to allow creating DImode 0's in VSX registers.  */
   8
   9 typedef union
  10 {
  11   long double value;
  12   struct
  13   {
  14     unsigned long long msw;
  15     unsigned long long lsw;
  16   } parts64;
  17   struct
  18   {
  19     unsigned int w0, w1, w2, w3;
  20   } parts32;
  21 } ieee854_long_double_shape_type;
  22
  23 static const long double twolm54 = 5.55111512312578270212e-17;
  24
  25 long double foo (long double x, int n)
  26 {
  27   long long k, hx, lx;
  28   ieee854_long_double_shape_type qw_u;
  29
  30   qw_u.value = x;
  31   hx = qw_u.parts64.msw;
  32   lx = qw_u.parts64.lsw;
  33
  34   k = ((hx >> 52) & 0x7ff) + n + 54;
  35
  36   qw_u.parts64.msw = ((hx & 0x800fffffffffffffULL) | (k << 52));
  37   qw_u.parts64.lsw = lx;
  38   x = qw_u.value;
  39
  40   return x*twolm54;
  41 }