Commit bc20b34e authored by Laurent Vivier's avatar Laurent Vivier
Browse files

target/m68k: implement fasin



Using a local m68k floatx80_asin()
[copied from previous:
Written by Andreas Grabher for Previous, NeXT Computer Emulator.]

Signed-off-by: default avatarLaurent Vivier <laurent@vivier.eu>
Message-Id: <20180312202728.23790-7-laurent@vivier.eu>
parent 8c992abc
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+5 −0
Original line number Diff line number Diff line
@@ -623,3 +623,8 @@ void HELPER(fatan)(CPUM68KState *env, FPReg *res, FPReg *val)
{
    res->d = floatx80_atan(val->d, &env->fp_status);
}

void HELPER(fasin)(CPUM68KState *env, FPReg *res, FPReg *val)
{
    res->d = floatx80_asin(val->d, &env->fp_status);
}
+1 −0
Original line number Diff line number Diff line
@@ -80,6 +80,7 @@ DEF_HELPER_3(fsin, void, env, fp, fp)
DEF_HELPER_3(fcos, void, env, fp, fp)
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(mac_move, void, env, i32, i32)
DEF_HELPER_3(macmulf, i64, env, i32, i32)
+65 −0
Original line number Diff line number Diff line
@@ -2167,3 +2167,68 @@ floatx80 floatx80_atan(floatx80 a, float_status *status)
        return a;
    }
}

/*----------------------------------------------------------------------------
 | Arc sine
 *----------------------------------------------------------------------------*/

floatx80 floatx80_asin(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_inexact, status);
            a = packFloatx80(aSign, piby2_exp, pi_sig);
            return floatx80_move(a, status);
        } 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);
    fp0 = a;

    fp1 = floatx80_sub(one, fp0, status);   /* 1 - X */
    fp2 = floatx80_add(one, fp0, status);   /* 1 + X */
    fp1 = floatx80_mul(fp2, fp1, status);   /* (1+X)*(1-X) */
    fp1 = floatx80_sqrt(fp1, status);       /* SQRT((1+X)*(1-X)) */
    fp0 = floatx80_div(fp0, fp1, status);   /* X/SQRT((1+X)*(1-X)) */

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

    a = floatx80_atan(fp0, status);         /* ATAN(X/SQRT((1+X)*(1-X))) */

    float_raise(float_flag_inexact, status);

    return a;
}
+1 −0
Original line number Diff line number Diff line
@@ -38,4 +38,5 @@ floatx80 floatx80_tan(floatx80 a, float_status *status);
floatx80 floatx80_sin(floatx80 a, float_status *status);
floatx80 floatx80_cos(floatx80 a, float_status *status);
floatx80 floatx80_atan(floatx80 a, float_status *status);
floatx80 floatx80_asin(floatx80 a, float_status *status);
#endif
+3 −0
Original line number Diff line number Diff line
@@ -5060,6 +5060,9 @@ DISAS_INSN(fpu)
    case 0x0a: /* fatan */
        gen_helper_fatan(cpu_env, cpu_dest, cpu_src);
        break;
    case 0x0c: /* fasin */
        gen_helper_fasin(cpu_env, cpu_dest, cpu_src);
        break;
    case 0x0e: /* fsin */
        gen_helper_fsin(cpu_env, cpu_dest, cpu_src);
        break;