/*      $OpenBSD: fcnvfx.c,v 1.8 2010/07/30 18:05:23 kettenis Exp $     */

/*
 * Copyright 1996 1995 by Open Software Foundation, Inc.
 *              All Rights Reserved
 *
 * Permission to use, copy, modify, and distribute this software and
 * its documentation for any purpose and without fee is hereby granted,
 * provided that the above copyright notice appears in all copies and
 * that both the copyright notice and this permission notice appear in
 * supporting documentation.
 *
 * OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
 * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE.
 *
 * IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
 * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
 * LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
 * NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
 * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 */
/*
 * pmk1.1
 */
/*
 * (c) Copyright 1986 HEWLETT-PACKARD COMPANY
 *
 * To anyone who acknowledges that this file is provided "AS IS"
 * without any express or implied warranty:
 *     permission to use, copy, modify, and distribute this file
 * for any purpose is hereby granted without fee, provided that
 * the above copyright notice and this notice appears in all
 * copies, and that the name of Hewlett-Packard Company not be
 * used in advertising or publicity pertaining to distribution
 * of the software without specific, written prior permission.
 * Hewlett-Packard Company makes no representations about the
 * suitability of this software for any purpose.
 */

#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: fcnvfx.c,v 1.6 2012/02/04 17:03:09 skrll Exp $");

#include "../spmath/float.h"
#include "../spmath/sgl_float.h"
#include "../spmath/dbl_float.h"
#include "../spmath/cnv_float.h"

/*
 *  Single Floating-point to Single Fixed-point
 */
/*ARGSUSED*/
int
sgl_to_sgl_fcnvfx(sgl_floating_point *srcptr, int *dstptr,
    unsigned int *status)
{
        register unsigned int src, temp;
        register int src_exponent, result;
        register int inexact = false;

        src = *srcptr;
        src_exponent = Sgl_exponent(src) - SGL_BIAS;

        /*
         * Test for overflow
         */
        if (src_exponent > SGL_FX_MAX_EXP) {
                /* check for MININT */
                if ((src_exponent > SGL_FX_MAX_EXP + 1) ||
                Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) {
                        if (Sgl_iszero_sign(src)) result = 0x7fffffff;
                        else result = 0x80000000;

                        if (Is_invalidtrap_enabled()) {
                                return(INVALIDEXCEPTION);
                        }
                        Set_invalidflag();
                        *dstptr = result;
                        return(NOEXCEPTION);
                }
        }
        /*
         * Generate result
         */
        if (src_exponent >= 0) {
                temp = src;
                Sgl_clear_signexponent_set_hidden(temp);
                Int_from_sgl_mantissa(temp,src_exponent);
                if (Sgl_isone_sign(src))  result = -Sgl_all(temp);
                else result = Sgl_all(temp);

                /* check for inexact */
                if (Sgl_isinexact_to_fix(src,src_exponent)) {
                        inexact = true;
                        /*  round result  */
                        switch (Rounding_mode()) {
                        case ROUNDPLUS:
                             if (Sgl_iszero_sign(src)) result++;
                             break;
                        case ROUNDMINUS:
                             if (Sgl_isone_sign(src)) result--;
                             break;
                        case ROUNDNEAREST:
                             if (Sgl_isone_roundbit(src,src_exponent)) {
                                if (Sgl_isone_stickybit(src,src_exponent)
                                || (Sgl_isone_lowmantissa(temp))) {
                                   if (Sgl_iszero_sign(src)) result++;
                                   else result--;
                                }
                             }
                        }
                }
        }
        else {
                result = 0;

                /* check for inexact */
                if (Sgl_isnotzero_exponentmantissa(src)) {
                        inexact = true;
                        /*  round result  */
                        switch (Rounding_mode()) {
                        case ROUNDPLUS:
                             if (Sgl_iszero_sign(src)) result++;
                             break;
                        case ROUNDMINUS:
                             if (Sgl_isone_sign(src)) result--;
                             break;
                        case ROUNDNEAREST:
                             if (src_exponent == -1)
                                if (Sgl_isnotzero_mantissa(src)) {
                                   if (Sgl_iszero_sign(src)) result++;
                                   else result--;
                                }
                        }
                }
        }
        *dstptr = result;
        if (inexact) {
                if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
                else Set_inexactflag();
        }
        return(NOEXCEPTION);
}

/*
 *  Single Floating-point to Double Fixed-point
 */
/*ARGSUSED*/
int
sgl_to_dbl_fcnvfx(sgl_floating_point *srcptr, dbl_integer *dstptr,
    unsigned int *status)
{
        register int src_exponent, resultp1;
        register unsigned int src, temp, resultp2;
        register int inexact = false;

        src = *srcptr;
        src_exponent = Sgl_exponent(src) - SGL_BIAS;

        /*
         * Test for overflow
         */
        if (src_exponent > DBL_FX_MAX_EXP) {
                /* check for MININT */
                if ((src_exponent > DBL_FX_MAX_EXP + 1) ||
                Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) {
                        if (Sgl_iszero_sign(src)) {
                                resultp1 = 0x7fffffff;
                                resultp2 = 0xffffffff;
                        }
                        else {
                                resultp1 = 0x80000000;
                                resultp2 = 0;
                        }

                        if (Is_invalidtrap_enabled()) {
                                return(INVALIDEXCEPTION);
                        }
                        Set_invalidflag();
                        Dint_copytoptr(resultp1,resultp2,dstptr);
                        return(NOEXCEPTION);
                }
                Dint_set_minint(resultp1,resultp2);
                Dint_copytoptr(resultp1,resultp2,dstptr);
                return(NOEXCEPTION);
        }
        /*
         * Generate result
         */
        if (src_exponent >= 0) {
                temp = src;
                Sgl_clear_signexponent_set_hidden(temp);
                Dint_from_sgl_mantissa(temp,src_exponent,resultp1,resultp2);
                if (Sgl_isone_sign(src)) {
                        Dint_setone_sign(resultp1,resultp2);
                }

                /* check for inexact */
                if (Sgl_isinexact_to_fix(src,src_exponent)) {
                        inexact = true;
                        /*  round result  */
                        switch (Rounding_mode()) {
                        case ROUNDPLUS:
                             if (Sgl_iszero_sign(src)) {
                                Dint_increment(resultp1,resultp2);
                             }
                             break;
                        case ROUNDMINUS:
                             if (Sgl_isone_sign(src)) {
                                Dint_decrement(resultp1,resultp2);
                             }
                             break;
                        case ROUNDNEAREST:
                             if (Sgl_isone_roundbit(src,src_exponent))
                                if (Sgl_isone_stickybit(src,src_exponent) ||
                                (Dint_isone_lowp2(resultp2))) {
                                   if (Sgl_iszero_sign(src)) {
                                      Dint_increment(resultp1,resultp2);
                                   }
                                   else {
                                      Dint_decrement(resultp1,resultp2);
                                   }
                                }
                        }
                }
        }
        else {
                Dint_setzero(resultp1,resultp2);

                /* check for inexact */
                if (Sgl_isnotzero_exponentmantissa(src)) {
                        inexact = true;
                        /*  round result  */
                        switch (Rounding_mode()) {
                        case ROUNDPLUS:
                             if (Sgl_iszero_sign(src)) {
                                Dint_increment(resultp1,resultp2);
                             }
                             break;
                        case ROUNDMINUS:
                             if (Sgl_isone_sign(src)) {
                                Dint_decrement(resultp1,resultp2);
                             }
                             break;
                        case ROUNDNEAREST:
                             if (src_exponent == -1)
                                if (Sgl_isnotzero_mantissa(src)) {
                                   if (Sgl_iszero_sign(src)) {
                                      Dint_increment(resultp1,resultp2);
                                   }
                                   else {
                                      Dint_decrement(resultp1,resultp2);
                                   }
                                }
                        }
                }
        }
        Dint_copytoptr(resultp1,resultp2,dstptr);
        if (inexact) {
                if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
                else Set_inexactflag();
        }
        return(NOEXCEPTION);
}

/*
 *  Double Floating-point to Single Fixed-point
 */
/*ARGSUSED*/
int
dbl_to_sgl_fcnvfx(dbl_floating_point *srcptr, int *dstptr,
   unsigned int *status)
{
        register unsigned int srcp1,srcp2, tempp1,tempp2;
        register int src_exponent, result;
        register int inexact = false;

        Dbl_copyfromptr(srcptr,srcp1,srcp2);
        src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;

        /*
         * Test for overflow
         */
        if (src_exponent > SGL_FX_MAX_EXP) {
                /* check for MININT */
                if (Dbl_isoverflow_to_int(src_exponent,srcp1,srcp2)) {
                        if (Dbl_iszero_sign(srcp1)) result = 0x7fffffff;
                        else result = 0x80000000;

                        if (Is_invalidtrap_enabled()) {
                                return(INVALIDEXCEPTION);
                        }
                        Set_invalidflag();
                        *dstptr = result;
                        return(NOEXCEPTION);
                }
        }
        /*
         * Generate result
         */
        if (src_exponent >= 0) {
                tempp1 = srcp1;
                tempp2 = srcp2;
                Dbl_clear_signexponent_set_hidden(tempp1);
                Int_from_dbl_mantissa(tempp1,tempp2,src_exponent);
                if (Dbl_isone_sign(srcp1) && (src_exponent <= SGL_FX_MAX_EXP))
                        result = -Dbl_allp1(tempp1);
                else result = Dbl_allp1(tempp1);

                /* check for inexact */
                if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
                        inexact = true;
                        /*  round result  */
                        switch (Rounding_mode()) {
                        case ROUNDPLUS:
                                if (Dbl_iszero_sign(srcp1))
                                        result++;
                             break;
                        case ROUNDMINUS:
                             if (Dbl_isone_sign(srcp1)) result--;
                             break;
                        case ROUNDNEAREST:
                             if (Dbl_isone_roundbit(srcp1,srcp2,src_exponent))
                                if (Dbl_isone_stickybit(srcp1,srcp2,src_exponent) ||
                                (Dbl_isone_lowmantissap1(tempp1))) {
                                   if (Dbl_iszero_sign(srcp1)) result++;
                                   else result--;
                                }
                        }
                        /* check for overflow */
                        if ((Dbl_iszero_sign(srcp1) && result < 0) ||
                            (Dbl_isone_sign(srcp1) && result > 0)) {

                                if (Dbl_iszero_sign(srcp1))
                                        result = 0x7fffffff;
                                else
                                        result = 0x80000000;

                            if (Is_overflowtrap_enabled()) {
                            if (Is_inexacttrap_enabled())
                              return(OVERFLOWEXCEPTION|INEXACTEXCEPTION);
                            else Set_inexactflag();
                            return(OVERFLOWEXCEPTION);
                            }
                          Set_overflowflag();
                          *dstptr = result;
                          if (Is_inexacttrap_enabled() )
                                return(INEXACTEXCEPTION);
                          else Set_inexactflag();
                          return(NOEXCEPTION);
                        }
                }
        }
        else {
                result = 0;

                /* check for inexact */
                if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
                        inexact = true;
                        /*  round result  */
                        switch (Rounding_mode()) {
                        case ROUNDPLUS:
                             if (Dbl_iszero_sign(srcp1)) result++;
                             break;
                        case ROUNDMINUS:
                             if (Dbl_isone_sign(srcp1)) result--;
                             break;
                        case ROUNDNEAREST:
                             if (src_exponent == -1)
                                if (Dbl_isnotzero_mantissa(srcp1,srcp2)) {
                                   if (Dbl_iszero_sign(srcp1)) result++;
                                   else result--;
                                }
                        }
                }
        }
        *dstptr = result;
        if (inexact) {
                if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
                else Set_inexactflag();
        }
        return(NOEXCEPTION);
}

/*
 *  Double Floating-point to Double Fixed-point
 */
/*ARGSUSED*/
int
dbl_to_dbl_fcnvfx(dbl_floating_point *srcptr, dbl_integer *dstptr,
    unsigned int *status)
{
        register int src_exponent, resultp1;
        register unsigned int srcp1, srcp2, tempp1, tempp2, resultp2;
        register int inexact = false;

        Dbl_copyfromptr(srcptr,srcp1,srcp2);
        src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;

        /*
         * Test for overflow
         */
        if (src_exponent > DBL_FX_MAX_EXP) {
                /* check for MININT */
                if ((src_exponent > DBL_FX_MAX_EXP + 1) ||
                Dbl_isnotzero_mantissa(srcp1,srcp2) || Dbl_iszero_sign(srcp1)) {
                        if (Dbl_iszero_sign(srcp1)) {
                                resultp1 = 0x7fffffff;
                                resultp2 = 0xffffffff;
                        }
                        else {
                                resultp1 = 0x80000000;
                                resultp2 = 0;
                        }

                        if (Is_invalidtrap_enabled()) {
                                return(INVALIDEXCEPTION);
                        }
                        Set_invalidflag();
                        Dint_copytoptr(resultp1,resultp2,dstptr);
                        return(NOEXCEPTION);
                }
        }

        /*
         * Generate result
         */
        if (src_exponent >= 0) {
                tempp1 = srcp1;
                tempp2 = srcp2;
                Dbl_clear_signexponent_set_hidden(tempp1);
                Dint_from_dbl_mantissa(tempp1,tempp2,src_exponent,
                                       resultp1, resultp2);
                if (Dbl_isone_sign(srcp1)) {
                        Dint_setone_sign(resultp1,resultp2);
                }

                /* check for inexact */
                if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
                        inexact = true;
                        /*  round result  */
                        switch (Rounding_mode()) {
                        case ROUNDPLUS:
                             if (Dbl_iszero_sign(srcp1)) {
                                Dint_increment(resultp1,resultp2);
                             }
                             break;
                        case ROUNDMINUS:
                             if (Dbl_isone_sign(srcp1)) {
                                Dint_decrement(resultp1,resultp2);
                             }
                             break;
                        case ROUNDNEAREST:
                             if (Dbl_isone_roundbit(srcp1,srcp2,src_exponent))
                                if (Dbl_isone_stickybit(srcp1,srcp2,src_exponent) ||
                                (Dint_isone_lowp2(resultp2))) {
                                   if (Dbl_iszero_sign(srcp1)) {
                                      Dint_increment(resultp1,resultp2);
                                   }
                                   else {
                                      Dint_decrement(resultp1,resultp2);
                                   }
                                }
                        }
                }
        }
        else {
                Dint_setzero(resultp1,resultp2);

                /* check for inexact */
                if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
                        inexact = true;
                        /*  round result  */
                        switch (Rounding_mode()) {
                        case ROUNDPLUS:
                             if (Dbl_iszero_sign(srcp1)) {
                                Dint_increment(resultp1,resultp2);
                             }
                             break;
                        case ROUNDMINUS:
                             if (Dbl_isone_sign(srcp1)) {
                                Dint_decrement(resultp1,resultp2);
                             }
                             break;
                        case ROUNDNEAREST:
                             if (src_exponent == -1)
                                if (Dbl_isnotzero_mantissa(srcp1,srcp2)) {
                                   if (Dbl_iszero_sign(srcp1)) {
                                      Dint_increment(resultp1,resultp2);
                                   }
                                   else {
                                      Dint_decrement(resultp1,resultp2);
                                   }
                                }
                        }
                }
        }
        Dint_copytoptr(resultp1,resultp2,dstptr);
        if (inexact) {
                if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
                else Set_inexactflag();
        }
        return(NOEXCEPTION);
}