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/* @(#)z_frexpf.c 1.0 98/08/13 */
/******************************************************************
* frexp
*
* Input:
* d - floating point value
* exp - exponent value
*
* Output:
* A floating point value in the range [0.5, 1).
*
* Description:
* This routine breaks a floating point value into a number f and
* an exponent exp such that d = f * 2 ^ exp.
*
*****************************************************************/
#include "fdlibm.h"
#include "zmath.h"
float frexpf (float d, int *exp)
{
float f;
__int32_t wf, wd;
/* Check for special values. */
switch (numtestf (d))
{
case NAN:
case INF:
errno = EDOM;
case 0:
*exp = 0;
return (d);
}
GET_FLOAT_WORD (wd, d);
/* Get the exponent. */
*exp = ((wd & 0x7f800000) >> 23) - 126;
/* Get the mantissa. */
wf = wd & 0x7fffff;
wf |= 0x3f000000;
SET_FLOAT_WORD (f, wf);
return (f);
}
#ifdef _DOUBLE_IS_32BITS
double frexp (double x, int *exp)
{
return (double) frexpf ((float) x, exp);
}
#endif /* defined(_DOUBLE_IS_32BITS) */
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