Commit e3655afa authored by Laurent Vivier's avatar Laurent Vivier
Browse files

target/m68k: implement fatanh



Using a local m68k floatx80_atanh()
[copied from previous:
Written by Andreas Grabher for Previous, NeXT Computer Emulator.]

Signed-off-by: default avatarLaurent Vivier <laurent@vivier.eu>
Message-Id: <20180312202728.23790-9-laurent@vivier.eu>
parent c84813b8
Loading
Loading
Loading
Loading
+5 −0
Original line number Diff line number Diff line
@@ -633,3 +633,8 @@ void HELPER(facos)(CPUM68KState *env, FPReg *res, FPReg *val)
{
    res->d = floatx80_acos(val->d, &env->fp_status);
}

void HELPER(fatanh)(CPUM68KState *env, FPReg *res, FPReg *val)
{
    res->d = floatx80_atanh(val->d, &env->fp_status);
}
+1 −0
Original line number Diff line number Diff line
@@ -82,6 +82,7 @@ DEF_HELPER_4(fsincos, void, env, fp, fp, fp)
DEF_HELPER_3(fatan, void, env, fp, fp)
DEF_HELPER_3(fasin, void, env, fp, fp)
DEF_HELPER_3(facos, void, env, fp, fp)
DEF_HELPER_3(fatanh, void, env, fp, fp)

DEF_HELPER_3(mac_move, void, env, i32, i32)
DEF_HELPER_3(macmulf, i64, env, i32, i32)
+65 −0
Original line number Diff line number Diff line
@@ -2302,3 +2302,68 @@ floatx80 floatx80_acos(floatx80 a, float_status *status)

    return a;
}

/*----------------------------------------------------------------------------
 | Hyperbolic arc tangent
 *----------------------------------------------------------------------------*/

floatx80 floatx80_atanh(floatx80 a, float_status *status)
{
    flag aSign;
    int32_t aExp;
    uint64_t aSig;

    int8_t user_rnd_mode, user_rnd_prec;

    int32_t compact;
    floatx80 fp0, fp1, fp2, one;

    aSig = extractFloatx80Frac(a);
    aExp = extractFloatx80Exp(a);
    aSign = extractFloatx80Sign(a);

    if (aExp == 0x7FFF && (uint64_t) (aSig << 1)) {
        return propagateFloatx80NaNOneArg(a, status);
    }

    if (aExp == 0 && aSig == 0) {
        return packFloatx80(aSign, 0, 0);
    }

    compact = floatx80_make_compact(aExp, aSig);

    if (compact >= 0x3FFF8000) { /* |X| >= 1 */
        if (aExp == one_exp && aSig == one_sig) { /* |X| == 1 */
            float_raise(float_flag_divbyzero, status);
            return packFloatx80(aSign, floatx80_infinity.high,
                                floatx80_infinity.low);
        } else { /* |X| > 1 */
            float_raise(float_flag_invalid, status);
            return floatx80_default_nan(status);
        }
    } /* |X| < 1 */

    user_rnd_mode = status->float_rounding_mode;
    user_rnd_prec = status->floatx80_rounding_precision;
    status->float_rounding_mode = float_round_nearest_even;
    status->floatx80_rounding_precision = 80;

    one = packFloatx80(0, one_exp, one_sig);
    fp2 = packFloatx80(aSign, 0x3FFE, one_sig); /* SIGN(X) * (1/2) */
    fp0 = packFloatx80(0, aExp, aSig); /* Y = |X| */
    fp1 = packFloatx80(1, aExp, aSig); /* -Y */
    fp0 = floatx80_add(fp0, fp0, status); /* 2Y */
    fp1 = floatx80_add(fp1, one, status); /* 1-Y */
    fp0 = floatx80_div(fp0, fp1, status); /* Z = 2Y/(1-Y) */
    fp0 = floatx80_lognp1(fp0, status); /* LOG1P(Z) */

    status->float_rounding_mode = user_rnd_mode;
    status->floatx80_rounding_precision = user_rnd_prec;

    a = floatx80_mul(fp0, fp2,
                     status); /* ATANH(X) = SIGN(X) * (1/2) * LOG1P(Z) */

    float_raise(float_flag_inexact, status);

    return a;
}
+1 −0
Original line number Diff line number Diff line
@@ -40,4 +40,5 @@ floatx80 floatx80_cos(floatx80 a, float_status *status);
floatx80 floatx80_atan(floatx80 a, float_status *status);
floatx80 floatx80_asin(floatx80 a, float_status *status);
floatx80 floatx80_acos(floatx80 a, float_status *status);
floatx80 floatx80_atanh(floatx80 a, float_status *status);
#endif
+3 −0
Original line number Diff line number Diff line
@@ -5063,6 +5063,9 @@ DISAS_INSN(fpu)
    case 0x0c: /* fasin */
        gen_helper_fasin(cpu_env, cpu_dest, cpu_src);
        break;
    case 0x0d: /* fatanh */
        gen_helper_fatanh(cpu_env, cpu_dest, cpu_src);
        break;
    case 0x0e: /* fsin */
        gen_helper_fsin(cpu_env, cpu_dest, cpu_src);
        break;