1 /* Round to long long int long double floating-point values.
2 IBM extended format long double version.
3 Copyright (C) 2006 Free Software Foundation, Inc.
4 This file is part of the GNU C Library.
6 The GNU C Library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Lesser General Public
8 License as published by the Free Software Foundation; either
9 version 2.1 of the License, or (at your option) any later version.
11 The GNU C Library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Lesser General Public License for more details.
16 You should have received a copy of the GNU Lesser General Public
17 License along with the GNU C Library; if not, write to the Free
18 Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
22 #include <fenv_libc.h>
23 #include <math_ldbl_opt.h>
30 __llrintl (long double x)
38 long long res, hi, lo;
41 ldbl_unpack (x, &xh, &xl);
43 /* Limit the range of values handled by the conversion to long long.
44 We do this because we aren't sure whether that conversion properly
47 ((__builtin_fabs (xh) <= -(double) (-__LONG_LONG_MAX__ - 1)), 1)
48 #if !defined (FE_INVALID)
53 save_round = fegetround ();
55 if (__builtin_expect ((xh == -(double) (-__LONG_LONG_MAX__ - 1)), 0))
57 /* When XH is 9223372036854775808.0, converting to long long will
58 overflow, resulting in an invalid operation. However, XL might
59 be negative and of sufficient magnitude that the overall long
60 double is in fact in range. Avoid raising an exception. In any
61 case we need to convert this value specially, because
62 the converted value is not exactly represented as a double
63 thus subtracting HI from XH suffers rounding error. */
64 hi = __LONG_LONG_MAX__;
72 ldbl_canonicalize (&xh, &xl);
76 /* Peg at max/min values, assuming that the above conversions do so.
77 Strictly speaking, we can return anything for values that overflow,
78 but this is more useful. */
81 /* This is just sign(hi) == sign(lo) && sign(res) != sign(hi). */
82 if (__builtin_expect (((~(hi ^ lo) & (res ^ hi)) < 0), 0))
86 ldbl_canonicalize (&xh, &xl);
94 && ((xh > 0.0 && xl < 0.0)
95 || (xh < 0.0 && xl > 0.0)
96 || (xl == 0.0 && (res & 1) == 0))))
106 if (res > 0 && (xh < 0.0 || (xh == 0.0 && xl < 0.0)))
108 else if (res < 0 && (xh > 0.0 || (xh == 0.0 && xl > 0.0)))
114 if (xh > 0.0 || (xh == 0.0 && xl > 0.0))
119 if (xh < 0.0 || (xh == 0.0 && xl < 0.0))
124 if (__builtin_expect (((~(hi ^ (res - hi)) & (res ^ hi)) < 0), 0))
132 hi = __LONG_LONG_MAX__;
134 hi = -__LONG_LONG_MAX__ - 1;
142 feraiseexcept (FE_INVALID);
147 long_double_symbol (libm, __llrintl, llrintl);