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-skip-if "do not override -mcpu" { powerpc*-*-* } { "-mcpu=*" } { "-mcpu=power7" } } */
   5 /* { dg-options "-O3 -mcpu=power7" } */
   6
   7 /* Cut down example from s_scalbnl that aborted on 32-bit when the fix for
   8    48053 went in to allow creating DImode 0's in VSX registers.  */
   9
  10 typedef union
  11 {
  12   long double value;
  13   struct
  14   {
  15     unsigned long long msw;
  16     unsigned long long lsw;
  17   } parts64;
  18   struct
  19   {
  20     unsigned int w0, w1, w2, w3;
  21   } parts32;
  22 } ieee854_long_double_shape_type;
  23
  24 static const long double twolm54 = 5.55111512312578270212e-17;
  25
  26 long double foo (long double x, int n)
  27 {
  28   long long k, hx, lx;
  29   ieee854_long_double_shape_type qw_u;
  30
  31   qw_u.value = x;
  32   hx = qw_u.parts64.msw;
  33   lx = qw_u.parts64.lsw;
  34
  35   k = ((hx >> 52) & 0x7ff) + n + 54;
  36
  37   qw_u.parts64.msw = ((hx & 0x800fffffffffffffULL) | (k << 52));
  38   qw_u.parts64.lsw = lx;
  39   x = qw_u.value;
  40
  41   return x*twolm54;
  42 }