Subversion Repositories openrisc_2011-10-31

/* @(#)s_copysign.c 5.1 93/09/24 */

/*

 * ====================================================

 * 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.

 * ====================================================

 */

/*

FUNCTION

<<copysign>>, <<copysignf>>---sign of <[y]>, magnitude of <[x]>

INDEX

        copysign

INDEX

        copysignf

ANSI_SYNOPSIS

        #include <math.h>

        double copysign (double <[x]>, double <[y]>);

        float copysignf (float <[x]>, float <[y]>);

TRAD_SYNOPSIS

        #include <math.h>

        double copysign (<[x]>, <[y]>)

        double <[x]>;

        double <[y]>;

        float copysignf (<[x]>, <[y]>)

        float <[x]>;

        float <[y]>;

DESCRIPTION

<<copysign>> constructs a number with the magnitude (absolute value)

of its first argument, <[x]>, and the sign of its second argument,

<[y]>.

<<copysignf>> does the same thing; the two functions differ only in

the type of their arguments and result.

RETURNS

<<copysign>> returns a <<double>> with the magnitude of

<[x]> and the sign of <[y]>.

<<copysignf>> returns a <<float>> with the magnitude of

<[x]> and the sign of <[y]>.

PORTABILITY

<<copysign>> is not required by either ANSI C or the System V Interface

Definition (Issue 2).

*/

/*

 * copysign(double x, double y)

 * copysign(x,y) returns a value with the magnitude of x and

 * with the sign bit of y.

 */

#include "fdlibm.h"

#ifndef _DOUBLE_IS_32BITS

#ifdef __STDC__

        double copysign(double x, double y)

#else

        double copysign(x,y)

        double x,y;

#endif

{

        __uint32_t hx,hy;

        GET_HIGH_WORD(hx,x);

        GET_HIGH_WORD(hy,y);

        SET_HIGH_WORD(x,(hx&0x7fffffff)|(hy&0x80000000));

        return x;

}

#endif /* _DOUBLE_IS_32BITS */