/*
 * 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 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1990, 1991 UNIX System Laboratories, Inc. */
/*      Copyright (c) 1988 AT&T */
/*        All Rights Reserved   */

#pragma weak _fpsetround = fpsetround

#include "lint.h"
#include <ieeefp.h>
#include "fp.h"

extern int      _sse_hw;
extern void     _getmxcsr(int *), _putmxcsr(int);

fp_rnd
fpsetround(fp_rnd newrnd)
{
        struct _cw87 cw;
        fp_rnd oldrnd;
        int     mxcsr;
        extern int __flt_rounds;  /* ANSI value for rounding */

        newrnd &= 0x3;  /* mask off all ubt last 2 bits */
        switch (newrnd) {       /* set ANSI rounding mode */
        case FP_RN:     __flt_rounds = 1;
                        break;
        case FP_RM:     __flt_rounds = 3;
                        break;
        case FP_RP:     __flt_rounds = 2;
                        break;
        case FP_RZ:     __flt_rounds = 0;
                        break;
        };
        _getcw(&cw);
        oldrnd = (fp_rnd)cw.rnd;
        cw.rnd = newrnd;
        _putcw(cw);
        if (_sse_hw) {
                _getmxcsr(&mxcsr);
                mxcsr = (mxcsr & ~0x6000) | ((int)newrnd << 13);
                _putmxcsr(mxcsr);
        }
        return (oldrnd);
}