newlib/libm/common/sf_isinf.c

   1 /*
   2  * isinff(x) returns 1 if x is +-infinity, else 0;
   3  *
   4  * isinf is a <math.h> macro in the C99 standard.  It was previously
   5  * implemented as isinf and isinff functions by newlib and are still declared
   6  * as such in <math.h>.  Newlib supplies it here as a function if the user
   7  * chooses to use it instead of the C99 macro.
   8  */
   9
  10 #include "fdlibm.h"
  11 #include <ieeefp.h>
  12
  13 #undef isinff
  14
  15 int
  16 isinff (float x)
  17 {
  18         __int32_t ix;
  19         GET_FLOAT_WORD(ix,x);
  20         ix &= 0x7fffffff;
  21         return FLT_UWORD_IS_INFINITE(ix);
  22 }
  23
  24 #ifdef _DOUBLE_IS_32BITS
  25
  26 #undef isinf
  27
  28 int
  29 isinf (double x)
  30 {
  31         return isinff((float) x);
  32 }
  33
  34 #endif /* defined(_DOUBLE_IS_32BITS) */