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/* @(#)w_pow.c 5.2 93/10/01 */
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
/*
* wrapper pow(x,y) return x**y
*/
#include "math.h"
#include "math_private.h"
#ifndef lint
static char rcsid[] = "$FreeBSD$";
#endif
double
pow(double x, double y) /* wrapper pow */
{
#ifdef _IEEE_LIBM
return __ieee754_pow(x,y);
#else
double z;
z=__ieee754_pow(x,y);
if(_LIB_VERSION == _IEEE_|| isnan(y)) return z;
if(isnan(x)) {
if(y==0.0)
return __kernel_standard(x,y,42); /* pow(NaN,0.0) */
else
return z;
}
if(x==0.0){
if(y==0.0)
return __kernel_standard(x,y,20); /* pow(0.0,0.0) */
if(finite(y)&&y<0.0)
return __kernel_standard(x,y,23); /* pow(0.0,negative) */
return z;
}
if(!finite(z)) {
if(finite(x)&&finite(y)) {
if(isnan(z))
return __kernel_standard(x,y,24); /* pow neg**non-int */
else
return __kernel_standard(x,y,21); /* pow overflow */
}
}
if(z==0.0&&finite(x)&&finite(y))
return __kernel_standard(x,y,22); /* pow underflow */
return z;
#endif
}
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