long double expl(long double x) { union IEEEl2bits u; long double hi, lo, t, twopk; int k; uint16_t hx, ix; DOPRINT_START(&x); /* Filter out exceptional cases. */ u.e = x; hx = u.xbits.expsign; ix = hx & 0x7fff; if (ix >= BIAS + 13) { /* |x| >= 8192 or x is NaN */ if (ix == BIAS + LDBL_MAX_EXP) { if (hx & 0x8000) /* x is -Inf or -NaN */ RETURNP(-1 / x); RETURNP(x + x); /* x is +Inf or +NaN */ } if (x > o_threshold) RETURNP(huge * huge); if (x < u_threshold) RETURNP(tiny * tiny); } else if (ix < BIAS - 114) { /* |x| < 0x1p-114 */ RETURN2P(1, x); /* 1 with inexact iff x != 0 */ } ENTERI(); twopk = 1; __k_expl(x, &hi, &lo, &k); t = SUM2P(hi, lo); /* Scale by 2**k. */ /* XXX sparc64 multiplication is so slow that scalbnl() is faster. */ if (k >= LDBL_MIN_EXP) { if (k == LDBL_MAX_EXP) RETURNI(t * 2 * 0x1p16383L); SET_LDBL_EXPSIGN(twopk, BIAS + k); RETURNI(t * twopk); } else { SET_LDBL_EXPSIGN(twopk, BIAS + k + 10000); RETURNI(t * twopk * twom10000); } }
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 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); }