root/usr/src/lib/libm/common/m9x/feexcept.c
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2011 Nexenta Systems, Inc.  All rights reserved.
 */
/*
 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma weak __feclearexcept = feclearexcept
#pragma weak __feraiseexcept = feraiseexcept
#pragma weak __fetestexcept = fetestexcept
#pragma weak __fegetexceptflag = fegetexceptflag
#pragma weak __fesetexceptflag = fesetexceptflag

#pragma weak feclearexcept96 = feclearexcept
#pragma weak feraiseexcept96 = feraiseexcept
#pragma weak fetestexcept96 = fetestexcept
#pragma weak fegetexceptflag96 = fegetexceptflag
#pragma weak fesetexceptflag96 = fesetexceptflag

#include <fenv.h>
#include <sys/ieeefp.h>
#include <ucontext.h>
#include <thread.h>
#include "fex_handler.h"
#include "fenv_inlines.h"


int feclearexcept(int e)
{
        unsigned long   fsr;

        __fenv_getfsr(&fsr);
        __fenv_set_ex(fsr, __fenv_get_ex(fsr) & ~e);
        __fenv_setfsr(&fsr);
        if (fex_get_log())
                __fex_update_te();
        return 0;
}

/*
*  note - __fex_hdlr depends on fetestexcept following feraiseexcept
*/
int feraiseexcept(int e)
{
        volatile double t;
        unsigned long   fsr;

        if (e & FE_INVALID) {
                t = 0.0;
                t /= 0.0;
        }
        if (e & FE_DIVBYZERO) {
                t = 1.0e300;
                t /= 0.0;
        }
        if (e & FE_OVERFLOW) {
                /* if overflow is not trapped, avoid raising inexact */
                __fenv_getfsr(&fsr);
                if (!(__fenv_get_te(fsr) & (1 << fp_trap_overflow))) {
                        __fenv_set_ex(fsr, __fenv_get_ex(fsr) | FE_OVERFLOW);
                        __fenv_setfsr(&fsr);
                }
                else {
                        t = 1.0e300;
                        t *= 1.0e300;
                }
        }
        if (e & FE_UNDERFLOW) {
                /* if underflow is not trapped, avoid raising inexact */
                __fenv_getfsr(&fsr);
                if (!(__fenv_get_te(fsr) & (1 << fp_trap_underflow))) {
                        __fenv_set_ex(fsr, __fenv_get_ex(fsr) | FE_UNDERFLOW);
                        __fenv_setfsr(&fsr);
                }
                else {
                        t = 1.0e-307;
                        t -= 1.001e-307;
                }
        }
        if (e & FE_INEXACT) {
                t = 1.0e300;
                t += 1.0e-307;
        }
        return 0;
}

int fetestexcept(int e)
{
        unsigned long   fsr;

        __fenv_getfsr(&fsr);
        return (int)__fenv_get_ex(fsr) & e;
}

int fegetexceptflag(fexcept_t *p, int e)
{
        unsigned long   fsr;

        __fenv_getfsr(&fsr);
        *p = (int)__fenv_get_ex(fsr) & e;
        return 0;
}

int fesetexceptflag(const fexcept_t *p, int e)
{
        unsigned long   fsr;

        __fenv_getfsr(&fsr);
        __fenv_set_ex(fsr, (((int)__fenv_get_ex(fsr) & ~e) | (*p & e)) &
                FE_ALL_EXCEPT);
        __fenv_setfsr(&fsr);
        if (fex_get_log())
                __fex_update_te();
        return 0;
}