diff --git a/ChangeLog b/ChangeLog index 6f79779923..e622d9e14a 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,5 +1,9 @@ 2016-02-18 Joseph Myers + [BZ #19592] + * sysdeps/ieee754/ldbl-128ibm/s_ceill.c (__ceill): Use __ceil on + high and low parts then use ldbl_canonicalize_int if needed. + [BZ #17899] * sysdeps/ieee754/ldbl-128ibm/math_ldbl.h (ldbl_canonicalize_int): New function. diff --git a/sysdeps/ieee754/ldbl-128ibm/s_ceill.c b/sysdeps/ieee754/ldbl-128ibm/s_ceill.c index ac649b7215..635fddc633 100644 --- a/sysdeps/ieee754/ldbl-128ibm/s_ceill.c +++ b/sysdeps/ieee754/ldbl-128ibm/s_ceill.c @@ -35,42 +35,22 @@ __ceill (long double x) && __builtin_isless (__builtin_fabs (xh), __builtin_inf ()), 1)) { - double orig_xh; - - /* Long double arithmetic, including the canonicalisation below, - only works in round-to-nearest mode. */ - - /* Convert the high double to integer. */ - orig_xh = xh; - hi = ldbl_nearbyint (xh); - - /* Subtract integral high part from the value. */ - xh -= hi; - ldbl_canonicalize (&xh, &xl); - - /* Now convert the low double, adjusted for any remainder from the - high double. */ - lo = ldbl_nearbyint (xh); - - /* Adjust the result when the remainder is non-zero. nearbyint - rounds values to the nearest integer, and values halfway - between integers to the nearest even integer. ceill must - round towards +Inf. */ - xh -= lo; - ldbl_canonicalize (&xh, &xl); - - if (xh > 0.0 || (xh == 0.0 && xl > 0.0)) - lo += 1.0; - - /* Ensure the final value is canonical. In certain cases, - rounding causes hi,lo calculated so far to be non-canonical. */ - xh = hi; - xl = lo; - ldbl_canonicalize (&xh, &xl); - - /* Ensure we return -0 rather than +0 when appropriate. */ - if (orig_xh < 0.0) - xh = -__builtin_fabs (xh); + hi = __ceil (xh); + if (hi != xh) + { + /* The high part is not an integer; the low part does not + affect the result. */ + xh = hi; + xl = 0; + } + else + { + /* The high part is a nonzero integer. */ + lo = __ceil (xl); + xh = hi; + xl = lo; + ldbl_canonicalize_int (&xh, &xl); + } } return ldbl_pack (xh, xl);