extended_cpdo.c

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/*
    NetWinder Floating Point Emulator
    (c) Rebel.COM, 1998,1999

    Direct questions, comments to Scott Bambrough <[email protected]>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "fpa11.h"
#include "softfloat.h"
#include "fpopcode.h"

floatx80 floatx80_exp(floatx80 Fm);
floatx80 floatx80_ln(floatx80 Fm);
floatx80 floatx80_sin(floatx80 rFm);
floatx80 floatx80_cos(floatx80 rFm);
floatx80 floatx80_arcsin(floatx80 rFm);
floatx80 floatx80_arctan(floatx80 rFm);
floatx80 floatx80_log(floatx80 rFm);
floatx80 floatx80_tan(floatx80 rFm);
floatx80 floatx80_arccos(floatx80 rFm);
floatx80 floatx80_pow(floatx80 rFn, floatx80 rFm);
floatx80 floatx80_pol(floatx80 rFn, floatx80 rFm);

static floatx80 floatx80_rsf(struct roundingData *roundData, floatx80 rFn, floatx80 rFm)
{
    return floatx80_sub(roundData, rFm, rFn);
}

static floatx80 floatx80_rdv(struct roundingData *roundData, floatx80 rFn, floatx80 rFm)
{
    return floatx80_div(roundData, rFm, rFn);
}

static floatx80 (*const dyadic_extended[16])(struct roundingData*, floatx80 rFn, floatx80 rFm) = {
    [ADF_CODE >> 20] = floatx80_add,
    [MUF_CODE >> 20] = floatx80_mul,
    [SUF_CODE >> 20] = floatx80_sub,
    [RSF_CODE >> 20] = floatx80_rsf,
    [DVF_CODE >> 20] = floatx80_div,
    [RDF_CODE >> 20] = floatx80_rdv,
    [RMF_CODE >> 20] = floatx80_rem,

    /* strictly, these opcodes should not be implemented */
    [FML_CODE >> 20] = floatx80_mul,
    [FDV_CODE >> 20] = floatx80_div,
    [FRD_CODE >> 20] = floatx80_rdv,
};

static floatx80 floatx80_mvf(struct roundingData *roundData, floatx80 rFm)
{
    return rFm;
}

static floatx80 floatx80_mnf(struct roundingData *roundData, floatx80 rFm)
{
    rFm.high ^= 0x8000;
    return rFm;
}

static floatx80 floatx80_abs(struct roundingData *roundData, floatx80 rFm)
{
    rFm.high &= 0x7fff;
    return rFm;
}

static floatx80 (*const monadic_extended[16])(struct roundingData*, floatx80 rFm) = {
    [MVF_CODE >> 20] = floatx80_mvf,
    [MNF_CODE >> 20] = floatx80_mnf,
    [ABS_CODE >> 20] = floatx80_abs,
    [RND_CODE >> 20] = floatx80_round_to_int,
    [URD_CODE >> 20] = floatx80_round_to_int,
    [SQT_CODE >> 20] = floatx80_sqrt,
    [NRM_CODE >> 20] = floatx80_mvf,
};

unsigned int ExtendedCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd)
{
    FPA11 *fpa11 = GET_FPA11();
    floatx80 rFm;
    unsigned int Fm, opc_mask_shift;

    Fm = getFm(opcode);
    if (CONSTANT_FM(opcode)) {
        rFm = getExtendedConstant(Fm);
    } else {
        switch (fpa11->fType[Fm]) {
        case typeSingle:
            rFm = float32_to_floatx80(fpa11->fpreg[Fm].fSingle);
            break;

        case typeDouble:
            rFm = float64_to_floatx80(fpa11->fpreg[Fm].fDouble);
            break;

        case typeExtended:
            rFm = fpa11->fpreg[Fm].fExtended;
            break;

        default:
            return 0;
        }
    }

    opc_mask_shift = (opcode & MASK_ARITHMETIC_OPCODE) >> 20;
    if (!MONADIC_INSTRUCTION(opcode)) {
        unsigned int Fn = getFn(opcode);
        floatx80 rFn;

        switch (fpa11->fType[Fn]) {
        case typeSingle:
            rFn = float32_to_floatx80(fpa11->fpreg[Fn].fSingle);
            break;

        case typeDouble:
            rFn = float64_to_floatx80(fpa11->fpreg[Fn].fDouble);
            break;

        case typeExtended:
            rFn = fpa11->fpreg[Fn].fExtended;
            break;

        default:
            return 0;
        }

        if (dyadic_extended[opc_mask_shift]) {
            rFd->fExtended = dyadic_extended[opc_mask_shift](roundData, rFn, rFm);
        } else {
            return 0;
        }
    } else {
        if (monadic_extended[opc_mask_shift]) {
            rFd->fExtended = monadic_extended[opc_mask_shift](roundData, rFm);
        } else {
            return 0;
        }
    }

    return 1;
}