Subversion Repositories openrisc_2011-10-31

/* @(#)w_sqrt.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

        <<sqrt>>, <<sqrtf>>---positive square root

INDEX

        sqrt

INDEX

        sqrtf

ANSI_SYNOPSIS

        #include <math.h>

        double sqrt(double <[x]>);

        float  sqrtf(float <[x]>);

TRAD_SYNOPSIS

        #include <math.h>

        double sqrt(<[x]>);

        float  sqrtf(<[x]>);

DESCRIPTION

        <<sqrt>> computes the positive square root of the argument.

        You can modify error handling for this function with

        <<matherr>>.

RETURNS

        On success, the square root is returned. If <[x]> is real and

        positive, then the result is positive.  If <[x]> is real and

        negative, the global value <<errno>> is set to <<EDOM>> (domain error).

PORTABILITY

        <<sqrt>> is ANSI C.  <<sqrtf>> is an extension.

*/

/*

 * wrapper sqrt(x)

 */

#include "fdlibm.h"

#include <errno.h>

#ifndef _DOUBLE_IS_32BITS

#ifdef __STDC__

        double sqrt(double x)           /* wrapper sqrt */

#else

        double sqrt(x)                  /* wrapper sqrt */

        double x;

#endif

{

#ifdef _IEEE_LIBM

        return __ieee754_sqrt(x);

#else

        struct exception exc;

        double z;

        z = __ieee754_sqrt(x);

        if(_LIB_VERSION == _IEEE_ || isnan(x)) return z;

        if(x<0.0) {

          exc.type = DOMAIN;

          exc.name = "sqrt";

          exc.err = 0;

          exc.arg1 = exc.arg2 = x;

          if (_LIB_VERSION == _SVID_)

            exc.retval = 0.0;

          else

            exc.retval = 0.0/0.0;

          if (_LIB_VERSION == _POSIX_)

            errno = EDOM;

          else if (!matherr(&exc)) {

            errno = EDOM;

          }

          if (exc.err != 0)

            errno = exc.err;

          return exc.retval;

        } else

            return z;

#endif

}

#endif /* defined(_DOUBLE_IS_32BITS) */