1 /* Compute remainder and a congruent to the quotient.
2 Copyright (C) 1997-2024 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
21 #include <math_private.h>
22 #include <math_ldbl_opt.h>
25 static const long double zero
= 0.0;
29 __remquol (long double x
, long double y
, int *quo
)
34 double xhi
, xlo
, yhi
, ylo
;
36 ldbl_unpack (x
, &xhi
, &xlo
);
37 EXTRACT_WORDS64 (hx
, xhi
);
38 EXTRACT_WORDS64 (lx
, xlo
);
39 ldbl_unpack (y
, &yhi
, &ylo
);
40 EXTRACT_WORDS64 (hy
, yhi
);
41 EXTRACT_WORDS64 (ly
, ylo
);
42 sx
= hx
& 0x8000000000000000ULL
;
43 qs
= sx
^ (hy
& 0x8000000000000000ULL
);
44 ly
^= hy
& 0x8000000000000000ULL
;
45 hy
&= 0x7fffffffffffffffLL
;
47 hx
&= 0x7fffffffffffffffLL
;
49 /* Purge off exception values. */
51 return (x
* y
) / (x
* y
); /* y = 0 */
52 if ((hx
>= 0x7ff0000000000000LL
) /* x not finite */
53 || (hy
> 0x7ff0000000000000LL
)) /* y is NaN */
54 return (x
* y
) / (x
* y
);
56 if (hy
<= 0x7fbfffffffffffffLL
)
57 x
= __ieee754_fmodl (x
, 8 * y
); /* now x < 8y */
59 if (((hx
- hy
) | (lx
- ly
)) == 0)
69 if (hy
<= 0x7fcfffffffffffffLL
&& x
>= 4 * y
)
74 if (hy
<= 0x7fdfffffffffffffLL
&& x
>= 2 * y
)
80 if (hy
< 0x0020000000000000LL
)
95 long double y_half
= 0.5L * y
;
108 *quo
= qs
? -cquo
: cquo
;
110 /* Ensure correct sign of zero result in round-downward mode. */
117 long_double_symbol (libm
, __remquol
, remquol
);