long double expm1l(long double x) { union IEEEl2bits u, v; long double hx2_hi, hx2_lo, q, r, r1, t, twomk, twopk, x_hi; long double x_lo, x2; double dr, dx, fn, r2; int k, n, n2; uint16_t hx, ix; DOPRINT_START(&x); /* Filter out exceptional cases. */ u.e = x; hx = u.xbits.expsign; ix = hx & 0x7fff; if (ix >= BIAS + 7) { /* |x| >= 128 or x is NaN */ if (ix == BIAS + LDBL_MAX_EXP) { if (hx & 0x8000) /* x is -Inf or -NaN */ RETURNP(-1 / x - 1); RETURNP(x + x); /* x is +Inf or +NaN */ } if (x > o_threshold) RETURNP(huge * huge); /* * expm1l() never underflows, but it must avoid * unrepresentable large negative exponents. We used a * much smaller threshold for large |x| above than in * expl() so as to handle not so large negative exponents * in the same way as large ones here. */ if (hx & 0x8000) /* x <= -128 */ RETURN2P(tiny, -1); /* good for x < -114ln2 - eps */ } ENTERI(); if (T1 < x && x < T2) { x2 = x * x; dx = x; if (x < T3) { if (ix < BIAS - 113) { /* |x| < 0x1p-113 */ /* x (rounded) with inexact if x != 0: */ RETURNPI(x == 0 ? x : (0x1p200 * x + fabsl(x)) * 0x1p-200); } q = x * x2 * C3 + x2 * x2 * (C4 + x * (C5 + x * (C6 + x * (C7 + x * (C8 + x * (C9 + x * (C10 + x * (C11 + x * (C12 + x * (C13 + dx * (C14 + dx * (C15 + dx * (C16 + dx * (C17 + dx * C18)))))))))))))); } else { q = x * x2 * D3 + x2 * x2 * (D4 + x * (D5 + x * (D6 + x * (D7 + x * (D8 + x * (D9 + x * (D10 + x * (D11 + x * (D12 + x * (D13 + dx * (D14 + dx * (D15 + dx * (D16 + dx * D17))))))))))))); } x_hi = (float)x; x_lo = x - x_hi; hx2_hi = x_hi * x_hi / 2; hx2_lo = x_lo * (x + x_hi) / 2; if (ix >= BIAS - 7) RETURN2PI(hx2_hi + x_hi, hx2_lo + x_lo + q); else RETURN2PI(x, hx2_lo + q + hx2_hi); } /* Reduce x to (k*ln2 + endpoint[n2] + r1 + r2). */ /* Use a specialized rint() to get fn. Assume round-to-nearest. */ fn = (double)x * INV_L + 0x1.8p52 - 0x1.8p52; #if defined(HAVE_EFFICIENT_IRINT) n = irint(fn); #else n = (int)fn; #endif n2 = (unsigned)n % INTERVALS; k = n >> LOG2_INTERVALS; r1 = x - fn * L1; r2 = fn * -L2; r = r1 + r2; /* Prepare scale factor. */ v.e = 1; v.xbits.expsign = BIAS + k; twopk = v.e; /* * Evaluate lower terms of * expl(endpoint[n2] + r1 + r2) = tbl[n2] * expl(r1 + r2). */ dr = r; q = r2 + r * r * (A2 + r * (A3 + r * (A4 + r * (A5 + r * (A6 + dr * (A7 + dr * (A8 + dr * (A9 + dr * A10)))))))); t = tbl[n2].lo + tbl[n2].hi; if (k == 0) { t = SUM2P(tbl[n2].hi - 1, tbl[n2].lo * (r1 + 1) + t * q + tbl[n2].hi * r1); RETURNI(t); } if (k == -1) { t = SUM2P(tbl[n2].hi - 2, tbl[n2].lo * (r1 + 1) + t * q + tbl[n2].hi * r1); RETURNI(t / 2); } if (k < -7) { t = SUM2P(tbl[n2].hi, tbl[n2].lo + t * (q + r1)); RETURNI(t * twopk - 1); } if (k > 2 * LDBL_MANT_DIG - 1) { t = SUM2P(tbl[n2].hi, tbl[n2].lo + t * (q + r1)); if (k == LDBL_MAX_EXP) RETURNI(t * 2 * 0x1p16383L - 1); RETURNI(t * twopk - 1); } v.xbits.expsign = BIAS - k; twomk = v.e; if (k > LDBL_MANT_DIG - 1) t = SUM2P(tbl[n2].hi, tbl[n2].lo - twomk + t * (q + r1)); else t = SUM2P(tbl[n2].hi - twomk, tbl[n2].lo + t * (q + r1)); RETURNI(t * twopk); }
long double tanhl(long double x) { long double hi,lo,s,x2,x4,z; double dx2; int16_t jx,ix; GET_LDBL_EXPSIGN(jx,x); ix = jx&0x7fff; /* x is INF or NaN */ if(ix>=0x7fff) { if (jx>=0) return one/x+one; /* tanh(+-inf)=+-1 */ else return one/x-one; /* tanh(NaN) = NaN */ } ENTERI(); /* |x| < 40 */ if (ix < 0x4004 || fabsl(x) < 40) { /* |x|<40 */ if (__predict_false(ix<BIAS-(LDBL_MANT_DIG+1)/2)) { /* |x|<TINY */ /* tanh(+-0) = +0; tanh(tiny) = tiny(-+) with inexact: */ return (x == 0 ? x : (0x1p200 * x - x) * 0x1p-200); } if (ix<0x3ffd) { /* |x|<0.25 */ x2 = x*x; #if LDBL_MANT_DIG == 64 x4 = x2*x2; RETURNI(((T19*x2 + T17)*x4 + (T15*x2 + T13))*(x2*x*x2*x4*x4) + ((T11*x2 + T9)*x4 + (T7*x2 + T5))*(x2*x*x2) + T3*(x2*x) + x); #elif LDBL_MANT_DIG == 113 dx2 = x2; #if 0 RETURNI(((((((((((((((T33*dx2 + T31)*dx2 + T29)*dx2 + T27)*dx2 + T25)*x2 + T23)*x2 + T21)*x2 + T19)*x2 + T17)*x2 + T15)*x2 + T13)*x2 + T11)*x2 + T9)*x2 + T7)*x2 + T5)* (x2*x*x2) + T3*(x2*x) + x); #else long double q = ((((((((((((((T33*dx2 + T31)*dx2 + T29)*dx2 + T27)*dx2 + T25)*x2 + T23)*x2 + T21)*x2 + T19)*x2 + T17)*x2 + T15)*x2 + T13)*x2 + T11)*x2 + T9)*x2 + T7)*x2 + T5)* (x2*x*x2); RETURNI(q + T3*(x2*x) + x); #endif #endif } k_hexpl(2*fabsl(x), &hi, &lo); if (ix<0x4001 && fabsl(x) < 1.5) /* |x|<1.5 */ z = divl(hi, lo, -0.5, hi, lo, 0.5); else z = one - one/(lo+0.5+hi); /* |x| >= 40, return +-1 */ } else { z = one - tiny; /* raise inexact flag */ } s = 1; if (jx<0) s = -1; RETURNI(s*z); }
long double expm1l(long double x) { union IEEEl2bits u, v; long double fn, hx2_hi, hx2_lo, q, r, r1, r2, t, twomk, twopk, x_hi; long double x_lo, x2, z; long double x4; int k, n, n2; uint16_t hx, ix; DOPRINT_START(&x); /* Filter out exceptional cases. */ u.e = x; hx = u.xbits.expsign; ix = hx & 0x7fff; if (ix >= BIAS + 6) { /* |x| >= 64 or x is NaN */ if (ix == BIAS + LDBL_MAX_EXP) { if (hx & 0x8000) /* x is -Inf, -NaN or unsupported */ RETURNP(-1 / x - 1); RETURNP(x + x); /* x is +Inf, +NaN or unsupported */ } if (x > o_threshold) RETURNP(huge * huge); /* * expm1l() never underflows, but it must avoid * unrepresentable large negative exponents. We used a * much smaller threshold for large |x| above than in * expl() so as to handle not so large negative exponents * in the same way as large ones here. */ if (hx & 0x8000) /* x <= -64 */ RETURN2P(tiny, -1); /* good for x < -65ln2 - eps */ } ENTERI(); if (T1 < x && x < T2) { if (ix < BIAS - 74) { /* |x| < 0x1p-74 (includes pseudos) */ /* x (rounded) with inexact if x != 0: */ RETURNPI(x == 0 ? x : (0x1p100 * x + fabsl(x)) * 0x1p-100); } x2 = x * x; x4 = x2 * x2; q = x4 * (x2 * (x4 * /* * XXX the number of terms is no longer good for * pairwise grouping of all except B3, and the * grouping is no longer from highest down. */ (x2 * B12 + (x * B11 + B10)) + (x2 * (x * B9 + B8) + (x * B7 + B6))) + (x * B5 + B4.e)) + x2 * x * B3.e; x_hi = (float)x; x_lo = x - x_hi; hx2_hi = x_hi * x_hi / 2; hx2_lo = x_lo * (x + x_hi) / 2; if (ix >= BIAS - 7) RETURN2PI(hx2_hi + x_hi, hx2_lo + x_lo + q); else RETURN2PI(x, hx2_lo + q + hx2_hi); } /* Reduce x to (k*ln2 + endpoint[n2] + r1 + r2). */ /* Use a specialized rint() to get fn. Assume round-to-nearest. */ fn = x * INV_L + 0x1.8p63 - 0x1.8p63; #if defined(HAVE_EFFICIENT_IRINTL) n = irintl(fn); #elif defined(HAVE_EFFICIENT_IRINT) n = irint(fn); #else n = (int)fn; #endif n2 = (unsigned)n % INTERVALS; k = n >> LOG2_INTERVALS; r1 = x - fn * L1; r2 = fn * -L2; r = r1 + r2; /* Prepare scale factor. */ v.e = 1; v.xbits.expsign = BIAS + k; twopk = v.e; /* * Evaluate lower terms of * expl(endpoint[n2] + r1 + r2) = tbl[n2] * expl(r1 + r2). */ z = r * r; q = r2 + z * (A2 + r * A3) + z * z * (A4 + r * A5) + z * z * z * A6; t = (long double)tbl[n2].lo + tbl[n2].hi; if (k == 0) { t = SUM2P(tbl[n2].hi - 1, tbl[n2].lo * (r1 + 1) + t * q + tbl[n2].hi * r1); RETURNI(t); } if (k == -1) { t = SUM2P(tbl[n2].hi - 2, tbl[n2].lo * (r1 + 1) + t * q + tbl[n2].hi * r1); RETURNI(t / 2); } if (k < -7) { t = SUM2P(tbl[n2].hi, tbl[n2].lo + t * (q + r1)); RETURNI(t * twopk - 1); } if (k > 2 * LDBL_MANT_DIG - 1) { t = SUM2P(tbl[n2].hi, tbl[n2].lo + t * (q + r1)); if (k == LDBL_MAX_EXP) RETURNI(t * 2 * 0x1p16383L - 1); RETURNI(t * twopk - 1); } v.xbits.expsign = BIAS - k; twomk = v.e; if (k > LDBL_MANT_DIG - 1) t = SUM2P(tbl[n2].hi, tbl[n2].lo - twomk + t * (q + r1)); else t = SUM2P(tbl[n2].hi - twomk, tbl[n2].lo + t * (q + r1)); RETURNI(t * twopk); }
long double cbrtl(long double x) { union IEEEl2bits u, v; long double r, s, t, w; double dr, dt, dx; float ft, fx; uint32_t hx; uint16_t expsign; int k; u.e = x; expsign = u.xbits.expsign; k = expsign & 0x7fff; /* * If x = +-Inf, then cbrt(x) = +-Inf. * If x = NaN, then cbrt(x) = NaN. */ if (k == BIAS + LDBL_MAX_EXP) return (x + x); ENTERI(); if (k == 0) { /* If x = +-0, then cbrt(x) = +-0. */ if ((u.bits.manh | u.bits.manl) == 0) RETURNI(x); /* Adjust subnormal numbers. */ u.e *= 0x1.0p514; k = u.bits.exp; k -= BIAS + 514; } else k -= BIAS; u.xbits.expsign = BIAS; v.e = 1; x = u.e; switch (k % 3) { case 1: case -2: x = 2*x; k--; break; case 2: case -1: x = 4*x; k -= 2; break; } v.xbits.expsign = (expsign & 0x8000) | (BIAS + k / 3); /* * The following is the guts of s_cbrtf, with the handling of * special values removed and extra care for accuracy not taken, * but with most of the extra accuracy not discarded. */ /* ~5-bit estimate: */ fx = x; GET_FLOAT_WORD(hx, fx); SET_FLOAT_WORD(ft, ((hx & 0x7fffffff) / 3 + B1)); /* ~16-bit estimate: */ dx = x; dt = ft; dr = dt * dt * dt; dt = dt * (dx + dx + dr) / (dx + dr + dr); /* ~47-bit estimate: */ dr = dt * dt * dt; dt = dt * (dx + dx + dr) / (dx + dr + dr); #if LDBL_MANT_DIG == 64 /* * dt is cbrtl(x) to ~47 bits (after x has been reduced to 1 <= x < 8). * Round it away from zero to 32 bits (32 so that t*t is exact, and * away from zero for technical reasons). */ volatile double vd2 = 0x1.0p32; volatile double vd1 = 0x1.0p-31; #define vd ((long double)vd2 + vd1) t = dt + vd - 0x1.0p32; #elif LDBL_MANT_DIG == 113 /* * Round dt away from zero to 47 bits. Since we don't trust the 47, * add 2 47-bit ulps instead of 1 to round up. Rounding is slow and * might be avoidable in this case, since on most machines dt will * have been evaluated in 53-bit precision and the technical reasons * for rounding up might not apply to either case in cbrtl() since * dt is much more accurate than needed. */ t = dt + 0x2.0p-46 + 0x1.0p60L - 0x1.0p60; #else #error "Unsupported long double format" #endif /* * Final step Newton iteration to 64 or 113 bits with * error < 0.667 ulps */ s=t*t; /* t*t is exact */ r=x/s; /* error <= 0.5 ulps; |r| < |t| */ w=t+t; /* t+t is exact */ r=(r-t)/(w+r); /* r-t is exact; w+r ~= 3*t */ t=t+t*r; /* error <= 0.5 + 0.5/3 + epsilon */ t *= v.e; RETURNI(t); }