single_cpdo.c

Go to the documentation of this file.

/*
    NetWinder Floating Point Emulator
    (c) Rebel.COM, 1998,1999
    (c) Philip Blundell, 2001

    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"

float32 float32_exp(float32 Fm);
float32 float32_ln(float32 Fm);
float32 float32_sin(float32 rFm);
float32 float32_cos(float32 rFm);
float32 float32_arcsin(float32 rFm);
float32 float32_arctan(float32 rFm);
float32 float32_log(float32 rFm);
float32 float32_tan(float32 rFm);
float32 float32_arccos(float32 rFm);
float32 float32_pow(float32 rFn, float32 rFm);
float32 float32_pol(float32 rFn, float32 rFm);

static float32 float32_rsf(struct roundingData *roundData, float32 rFn, float32 rFm)
{
    return float32_sub(roundData, rFm, rFn);
}

static float32 float32_rdv(struct roundingData *roundData, float32 rFn, float32 rFm)
{
    return float32_div(roundData, rFm, rFn);
}

static float32 (*const dyadic_single[16])(struct roundingData *, float32 rFn, float32 rFm) = {
    [ADF_CODE >> 20] = float32_add,
    [MUF_CODE >> 20] = float32_mul,
    [SUF_CODE >> 20] = float32_sub,
    [RSF_CODE >> 20] = float32_rsf,
    [DVF_CODE >> 20] = float32_div,
    [RDF_CODE >> 20] = float32_rdv,
    [RMF_CODE >> 20] = float32_rem,

    [FML_CODE >> 20] = float32_mul,
    [FDV_CODE >> 20] = float32_div,
    [FRD_CODE >> 20] = float32_rdv,
};

static float32 float32_mvf(struct roundingData *roundData, float32 rFm)
{
    return rFm;
}

static float32 float32_mnf(struct roundingData *roundData, float32 rFm)
{
    return rFm ^ 0x80000000;
}

static float32 float32_abs(struct roundingData *roundData, float32 rFm)
{
    return rFm & 0x7fffffff;
}

static float32 (*const monadic_single[16])(struct roundingData*, float32 rFm) = {
    [MVF_CODE >> 20] = float32_mvf,
    [MNF_CODE >> 20] = float32_mnf,
    [ABS_CODE >> 20] = float32_abs,
    [RND_CODE >> 20] = float32_round_to_int,
    [URD_CODE >> 20] = float32_round_to_int,
    [SQT_CODE >> 20] = float32_sqrt,
    [NRM_CODE >> 20] = float32_mvf,
};

unsigned int SingleCPDO(struct roundingData *roundData, const unsigned int opcode, FPREG * rFd)
{
    FPA11 *fpa11 = GET_FPA11();
    float32 rFm;
    unsigned int Fm, opc_mask_shift;

    Fm = getFm(opcode);
    if (CONSTANT_FM(opcode)) {
        rFm = getSingleConstant(Fm);
    } else if (fpa11->fType[Fm] == typeSingle) {
        rFm = fpa11->fpreg[Fm].fSingle;
    } else {
        return 0;
    }

    opc_mask_shift = (opcode & MASK_ARITHMETIC_OPCODE) >> 20;
    if (!MONADIC_INSTRUCTION(opcode)) {
        unsigned int Fn = getFn(opcode);
        float32 rFn;

        if (fpa11->fType[Fn] == typeSingle &&
            dyadic_single[opc_mask_shift]) {
            rFn = fpa11->fpreg[Fn].fSingle;
            rFd->fSingle = dyadic_single[opc_mask_shift](roundData, rFn, rFm);
        } else {
            return 0;
        }
    } else {
        if (monadic_single[opc_mask_shift]) {
            rFd->fSingle = monadic_single[opc_mask_shift](roundData, rFm);
        } else {
            return 0;
        }
    }

    return 1;
}