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/*
* isinf(x) returns 1 if x is infinity, else 0;
* no branching!
*
* isinf is a <math.h> macro in the C99 standard. It was previously
* implemented as a function by newlib and is declared as such in
* <ieeefp.h>. Newlib supplies it here as a function if the user
* chooses to use <ieeefp.h> or needs to link older code compiled with the
* previous <math.h> declaration.
*/
#include "fdlibm.h"
#include <ieeefp.h>
#ifndef _DOUBLE_IS_32BITS
int
_DEFUN (isinf, (x),
double x)
{
__int32_t hx,lx;
EXTRACT_WORDS(hx,lx,x);
hx &= 0x7fffffff;
hx |= (__uint32_t)(lx|(-lx))>>31;
hx = 0x7ff00000 - hx;
return 1 - (int)((__uint32_t)(hx|(-hx))>>31);
}
#endif /* _DOUBLE_IS_32BITS */
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