newlib-cygwin/newlib/libm/common/sf_isinf.c

37 lines
666 B
C

/*
* isinff(x) returns 1 if x is +-infinity, else 0;
*
* isinf is a <math.h> macro in the C99 standard. It was previously
* implemented as isinf and isinff functions by newlib and are still declared
* as such in <math.h>. Newlib supplies it here as a function if the user
* chooses to use it instead of the C99 macro.
*/
#include "fdlibm.h"
#include <ieeefp.h>
#undef isinff
int
_DEFUN (isinff, (x),
float x)
{
__int32_t ix;
GET_FLOAT_WORD(ix,x);
ix &= 0x7fffffff;
return FLT_UWORD_IS_INFINITE(ix);
}
#ifdef _DOUBLE_IS_32BITS
#undef isinf
int
_DEFUN (isinf, (x),
double x)
{
return isinff((float) x);
}
#endif /* defined(_DOUBLE_IS_32BITS) */