diff options
Diffstat (limited to 'target/m68k/softfloat.c')
| -rw-r--r-- | target/m68k/softfloat.c | 366 |
1 files changed, 366 insertions, 0 deletions
diff --git a/target/m68k/softfloat.c b/target/m68k/softfloat.c index 5ce8413e96..4ce5783f03 100644 --- a/target/m68k/softfloat.c +++ b/target/m68k/softfloat.c @@ -2367,3 +2367,369 @@ floatx80 floatx80_atanh(floatx80 a, float_status *status) return a; } + +/*---------------------------------------------------------------------------- + | e to x minus 1 + *----------------------------------------------------------------------------*/ + +floatx80 floatx80_etoxm1(floatx80 a, float_status *status) +{ + flag aSign; + int32_t aExp; + uint64_t aSig; + + int8_t user_rnd_mode, user_rnd_prec; + + int32_t compact, n, j, m, m1; + floatx80 fp0, fp1, fp2, fp3, l2, sc, onebysc; + + aSig = extractFloatx80Frac(a); + aExp = extractFloatx80Exp(a); + aSign = extractFloatx80Sign(a); + + if (aExp == 0x7FFF) { + if ((uint64_t) (aSig << 1)) { + return propagateFloatx80NaNOneArg(a, status); + } + if (aSign) { + return packFloatx80(aSign, one_exp, one_sig); + } + return packFloatx80(0, floatx80_infinity.high, + floatx80_infinity.low); + } + + if (aExp == 0 && aSig == 0) { + return packFloatx80(aSign, 0, 0); + } + + 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; + + if (aExp >= 0x3FFD) { /* |X| >= 1/4 */ + compact = floatx80_make_compact(aExp, aSig); + + if (compact <= 0x4004C215) { /* |X| <= 70 log2 */ + fp0 = a; + fp1 = a; + fp0 = floatx80_mul(fp0, float32_to_floatx80( + make_float32(0x42B8AA3B), status), + status); /* 64/log2 * X */ + n = floatx80_to_int32(fp0, status); /* int(64/log2*X) */ + fp0 = int32_to_floatx80(n, status); + + j = n & 0x3F; /* J = N mod 64 */ + m = n / 64; /* NOTE: this is really arithmetic right shift by 6 */ + if (n < 0 && j) { + /* arithmetic right shift is division and + * round towards minus infinity + */ + m--; + } + m1 = -m; + /*m += 0x3FFF; // biased exponent of 2^(M) */ + /*m1 += 0x3FFF; // biased exponent of -2^(-M) */ + + fp2 = fp0; /* N */ + fp0 = floatx80_mul(fp0, float32_to_floatx80( + make_float32(0xBC317218), status), + status); /* N * L1, L1 = lead(-log2/64) */ + l2 = packFloatx80(0, 0x3FDC, LIT64(0x82E308654361C4C6)); + fp2 = floatx80_mul(fp2, l2, status); /* N * L2, L1+L2 = -log2/64 */ + fp0 = floatx80_add(fp0, fp1, status); /* X + N*L1 */ + fp0 = floatx80_add(fp0, fp2, status); /* R */ + + fp1 = floatx80_mul(fp0, fp0, status); /* S = R*R */ + fp2 = float32_to_floatx80(make_float32(0x3950097B), + status); /* A6 */ + fp2 = floatx80_mul(fp2, fp1, status); /* fp2 is S*A6 */ + fp3 = floatx80_mul(float32_to_floatx80(make_float32(0x3AB60B6A), + status), fp1, status); /* fp3 is S*A5 */ + fp2 = floatx80_add(fp2, float64_to_floatx80( + make_float64(0x3F81111111174385), status), + status); /* fp2 IS A4+S*A6 */ + fp3 = floatx80_add(fp3, float64_to_floatx80( + make_float64(0x3FA5555555554F5A), status), + status); /* fp3 is A3+S*A5 */ + fp2 = floatx80_mul(fp2, fp1, status); /* fp2 IS S*(A4+S*A6) */ + fp3 = floatx80_mul(fp3, fp1, status); /* fp3 IS S*(A3+S*A5) */ + fp2 = floatx80_add(fp2, float64_to_floatx80( + make_float64(0x3FC5555555555555), status), + status); /* fp2 IS A2+S*(A4+S*A6) */ + fp3 = floatx80_add(fp3, float32_to_floatx80( + make_float32(0x3F000000), status), + status); /* fp3 IS A1+S*(A3+S*A5) */ + fp2 = floatx80_mul(fp2, fp1, + status); /* fp2 IS S*(A2+S*(A4+S*A6)) */ + fp1 = floatx80_mul(fp1, fp3, + status); /* fp1 IS S*(A1+S*(A3+S*A5)) */ + fp2 = floatx80_mul(fp2, fp0, + status); /* fp2 IS R*S*(A2+S*(A4+S*A6)) */ + fp0 = floatx80_add(fp0, fp1, + status); /* fp0 IS R+S*(A1+S*(A3+S*A5)) */ + fp0 = floatx80_add(fp0, fp2, status); /* fp0 IS EXP(R) - 1 */ + + fp0 = floatx80_mul(fp0, exp_tbl[j], + status); /* 2^(J/64)*(Exp(R)-1) */ + + if (m >= 64) { + fp1 = float32_to_floatx80(exp_tbl2[j], status); + onebysc = packFloatx80(1, m1 + 0x3FFF, one_sig); /* -2^(-M) */ + fp1 = floatx80_add(fp1, onebysc, status); + fp0 = floatx80_add(fp0, fp1, status); + fp0 = floatx80_add(fp0, exp_tbl[j], status); + } else if (m < -3) { + fp0 = floatx80_add(fp0, float32_to_floatx80(exp_tbl2[j], + status), status); + fp0 = floatx80_add(fp0, exp_tbl[j], status); + onebysc = packFloatx80(1, m1 + 0x3FFF, one_sig); /* -2^(-M) */ + fp0 = floatx80_add(fp0, onebysc, status); + } else { /* -3 <= m <= 63 */ + fp1 = exp_tbl[j]; + fp0 = floatx80_add(fp0, float32_to_floatx80(exp_tbl2[j], + status), status); + onebysc = packFloatx80(1, m1 + 0x3FFF, one_sig); /* -2^(-M) */ + fp1 = floatx80_add(fp1, onebysc, status); + fp0 = floatx80_add(fp0, fp1, status); + } + + sc = packFloatx80(0, m + 0x3FFF, one_sig); + + status->float_rounding_mode = user_rnd_mode; + status->floatx80_rounding_precision = user_rnd_prec; + + a = floatx80_mul(fp0, sc, status); + + float_raise(float_flag_inexact, status); + + return a; + } else { /* |X| > 70 log2 */ + if (aSign) { + fp0 = float32_to_floatx80(make_float32(0xBF800000), + status); /* -1 */ + + status->float_rounding_mode = user_rnd_mode; + status->floatx80_rounding_precision = user_rnd_prec; + + a = floatx80_add(fp0, float32_to_floatx80( + make_float32(0x00800000), status), + status); /* -1 + 2^(-126) */ + + float_raise(float_flag_inexact, status); + + return a; + } else { + status->float_rounding_mode = user_rnd_mode; + status->floatx80_rounding_precision = user_rnd_prec; + + return floatx80_etox(a, status); + } + } + } else { /* |X| < 1/4 */ + if (aExp >= 0x3FBE) { + fp0 = a; + fp0 = floatx80_mul(fp0, fp0, status); /* S = X*X */ + fp1 = float32_to_floatx80(make_float32(0x2F30CAA8), + status); /* B12 */ + fp1 = floatx80_mul(fp1, fp0, status); /* S * B12 */ + fp2 = float32_to_floatx80(make_float32(0x310F8290), + status); /* B11 */ + fp1 = floatx80_add(fp1, float32_to_floatx80( + make_float32(0x32D73220), status), + status); /* B10 */ + fp2 = floatx80_mul(fp2, fp0, status); + fp1 = floatx80_mul(fp1, fp0, status); + fp2 = floatx80_add(fp2, float32_to_floatx80( + make_float32(0x3493F281), status), + status); /* B9 */ + fp1 = floatx80_add(fp1, float64_to_floatx80( + make_float64(0x3EC71DE3A5774682), status), + status); /* B8 */ + fp2 = floatx80_mul(fp2, fp0, status); + fp1 = floatx80_mul(fp1, fp0, status); + fp2 = floatx80_add(fp2, float64_to_floatx80( + make_float64(0x3EFA01A019D7CB68), status), + status); /* B7 */ + fp1 = floatx80_add(fp1, float64_to_floatx80( + make_float64(0x3F2A01A01A019DF3), status), + status); /* B6 */ + fp2 = floatx80_mul(fp2, fp0, status); + fp1 = floatx80_mul(fp1, fp0, status); + fp2 = floatx80_add(fp2, float64_to_floatx80( + make_float64(0x3F56C16C16C170E2), status), + status); /* B5 */ + fp1 = floatx80_add(fp1, float64_to_floatx80( + make_float64(0x3F81111111111111), status), + status); /* B4 */ + fp2 = floatx80_mul(fp2, fp0, status); + fp1 = floatx80_mul(fp1, fp0, status); + fp2 = floatx80_add(fp2, float64_to_floatx80( + make_float64(0x3FA5555555555555), status), + status); /* B3 */ + fp3 = packFloatx80(0, 0x3FFC, LIT64(0xAAAAAAAAAAAAAAAB)); + fp1 = floatx80_add(fp1, fp3, status); /* B2 */ + fp2 = floatx80_mul(fp2, fp0, status); + fp1 = floatx80_mul(fp1, fp0, status); + + fp2 = floatx80_mul(fp2, fp0, status); + fp1 = floatx80_mul(fp1, a, status); + + fp0 = floatx80_mul(fp0, float32_to_floatx80( + make_float32(0x3F000000), status), + status); /* S*B1 */ + fp1 = floatx80_add(fp1, fp2, status); /* Q */ + fp0 = floatx80_add(fp0, fp1, status); /* S*B1+Q */ + + status->float_rounding_mode = user_rnd_mode; + status->floatx80_rounding_precision = user_rnd_prec; + + a = floatx80_add(fp0, a, status); + + float_raise(float_flag_inexact, status); + + return a; + } else { /* |X| < 2^(-65) */ + sc = packFloatx80(1, 1, one_sig); + fp0 = a; + + if (aExp < 0x0033) { /* |X| < 2^(-16382) */ + fp0 = floatx80_mul(fp0, float64_to_floatx80( + make_float64(0x48B0000000000000), status), + status); + fp0 = floatx80_add(fp0, sc, status); + + status->float_rounding_mode = user_rnd_mode; + status->floatx80_rounding_precision = user_rnd_prec; + + a = floatx80_mul(fp0, float64_to_floatx80( + make_float64(0x3730000000000000), status), + status); + } else { + status->float_rounding_mode = user_rnd_mode; + status->floatx80_rounding_precision = user_rnd_prec; + + a = floatx80_add(fp0, sc, status); + } + + float_raise(float_flag_inexact, status); + + return a; + } + } +} + +/*---------------------------------------------------------------------------- + | Hyperbolic tangent + *----------------------------------------------------------------------------*/ + +floatx80 floatx80_tanh(floatx80 a, float_status *status) +{ + flag aSign, vSign; + int32_t aExp, vExp; + uint64_t aSig, vSig; + + int8_t user_rnd_mode, user_rnd_prec; + + int32_t compact; + floatx80 fp0, fp1; + uint32_t sign; + + aSig = extractFloatx80Frac(a); + aExp = extractFloatx80Exp(a); + aSign = extractFloatx80Sign(a); + + if (aExp == 0x7FFF) { + if ((uint64_t) (aSig << 1)) { + return propagateFloatx80NaNOneArg(a, status); + } + return packFloatx80(aSign, one_exp, one_sig); + } + + if (aExp == 0 && aSig == 0) { + return packFloatx80(aSign, 0, 0); + } + + 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; + + compact = floatx80_make_compact(aExp, aSig); + + if (compact < 0x3FD78000 || compact > 0x3FFFDDCE) { + /* TANHBORS */ + if (compact < 0x3FFF8000) { + /* TANHSM */ + status->float_rounding_mode = user_rnd_mode; + status->floatx80_rounding_precision = user_rnd_prec; + + a = floatx80_move(a, status); + + float_raise(float_flag_inexact, status); + + return a; + } else { + if (compact > 0x40048AA1) { + /* TANHHUGE */ + sign = 0x3F800000; + sign |= aSign ? 0x80000000 : 0x00000000; + fp0 = float32_to_floatx80(make_float32(sign), status); + sign &= 0x80000000; + sign ^= 0x80800000; /* -SIGN(X)*EPS */ + + status->float_rounding_mode = user_rnd_mode; + status->floatx80_rounding_precision = user_rnd_prec; + + a = floatx80_add(fp0, float32_to_floatx80(make_float32(sign), + status), status); + + float_raise(float_flag_inexact, status); + + return a; + } else { + fp0 = packFloatx80(0, aExp + 1, aSig); /* Y = 2|X| */ + fp0 = floatx80_etox(fp0, status); /* FP0 IS EXP(Y) */ + fp0 = floatx80_add(fp0, float32_to_floatx80( + make_float32(0x3F800000), + status), status); /* EXP(Y)+1 */ + sign = aSign ? 0x80000000 : 0x00000000; + fp1 = floatx80_div(float32_to_floatx80(make_float32( + sign ^ 0xC0000000), status), fp0, + status); /* -SIGN(X)*2 / [EXP(Y)+1] */ + fp0 = float32_to_floatx80(make_float32(sign | 0x3F800000), + status); /* SIGN */ + + status->float_rounding_mode = user_rnd_mode; + status->floatx80_rounding_precision = user_rnd_prec; + + a = floatx80_add(fp1, fp0, status); + + float_raise(float_flag_inexact, status); + + return a; + } + } + } else { /* 2**(-40) < |X| < (5/2)LOG2 */ + fp0 = packFloatx80(0, aExp + 1, aSig); /* Y = 2|X| */ + fp0 = floatx80_etoxm1(fp0, status); /* FP0 IS Z = EXPM1(Y) */ + fp1 = floatx80_add(fp0, float32_to_floatx80(make_float32(0x40000000), + status), + status); /* Z+2 */ + + vSign = extractFloatx80Sign(fp1); + vExp = extractFloatx80Exp(fp1); + vSig = extractFloatx80Frac(fp1); + + fp1 = packFloatx80(vSign ^ aSign, vExp, vSig); + + status->float_rounding_mode = user_rnd_mode; + status->floatx80_rounding_precision = user_rnd_prec; + + a = floatx80_div(fp0, fp1, status); + + float_raise(float_flag_inexact, status); + + return a; + } +} |