diff options
Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/e_acosl.c')
| -rw-r--r-- | sysdeps/ieee754/ldbl-128ibm/e_acosl.c | 38 |
1 files changed, 20 insertions, 18 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/e_acosl.c b/sysdeps/ieee754/ldbl-128ibm/e_acosl.c index 5d2af30346..2cb288238b 100644 --- a/sysdeps/ieee754/ldbl-128ibm/e_acosl.c +++ b/sysdeps/ieee754/ldbl-128ibm/e_acosl.c @@ -151,26 +151,27 @@ static const long double long double __ieee754_acosl (long double x) { - long double z, r, w, p, q, s, t, f2; - ieee854_long_double_shape_type u; + long double a, z, r, w, p, q, s, t, f2; - u.value = __builtin_fabsl (x); - if (u.value == 1.0L) + if (__glibc_unlikely (__isnanl (x))) + return x + x; + a = __builtin_fabsl (x); + if (a == 1.0L) { if (x > 0.0L) return 0.0; /* acos(1) = 0 */ else return (2.0 * pio2_hi) + (2.0 * pio2_lo); /* acos(-1)= pi */ } - else if (u.value > 1.0L) + else if (a > 1.0L) { return (x - x) / (x - x); /* acos(|x| > 1) is NaN */ } - if (u.value < 0.5L) + if (a < 0.5L) { - if (u.value < 6.938893903907228e-18L) /* |x| < 2**-57 */ + if (a < 6.938893903907228e-18L) /* |x| < 2**-57 */ return pio2_hi + pio2_lo; - if (u.value < 0.4375L) + if (a < 0.4375L) { /* Arcsine of x. */ z = x * x; @@ -199,7 +200,7 @@ __ieee754_acosl (long double x) return z; } /* .4375 <= |x| < .5 */ - t = u.value - 0.4375L; + t = a - 0.4375L; p = ((((((((((P10 * t + P9) * t + P8) * t @@ -230,9 +231,9 @@ __ieee754_acosl (long double x) r = acosr4375 + r; return r; } - else if (u.value < 0.625L) + else if (a < 0.625L) { - t = u.value - 0.5625L; + t = a - 0.5625L; p = ((((((((((rS10 * t + rS9) * t + rS8) * t @@ -264,7 +265,9 @@ __ieee754_acosl (long double x) } else { /* |x| >= .625 */ - z = (one - u.value) * 0.5; + double shi, slo; + + z = (one - a) * 0.5; s = __ieee754_sqrtl (z); /* Compute an extended precision square root from the Newton iteration s -> 0.5 * (s + z / s). @@ -273,12 +276,11 @@ __ieee754_acosl (long double x) Express s = f1 + f2 where f1 * f1 is exactly representable. w = (z - s^2)/2s = (z - f1^2 - 2 f1 f2 - f2^2)/2s . s + w has extended precision. */ - u.value = s; - u.parts32.w2 = 0; - u.parts32.w3 = 0; - f2 = s - u.value; - w = z - u.value * u.value; - w = w - 2.0 * u.value * f2; + ldbl_unpack (s, &shi, &slo); + a = shi; + f2 = slo; + w = z - a * a; + w = w - 2.0 * a * f2; w = w - f2 * f2; w = w / (2.0 * s); /* Arcsine of s. */ |