diff options
Diffstat (limited to 'sysdeps/ieee754/dbl-64/s_remquo.c')
| -rw-r--r-- | sysdeps/ieee754/dbl-64/s_remquo.c | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/sysdeps/ieee754/dbl-64/s_remquo.c b/sysdeps/ieee754/dbl-64/s_remquo.c new file mode 100644 index 0000000000..6e32efbba2 --- /dev/null +++ b/sysdeps/ieee754/dbl-64/s_remquo.c @@ -0,0 +1,113 @@ +/* Compute remainder and a congruent to the quotient. + Copyright (C) 1997 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public License as + published by the Free Software Foundation; either version 2 of the + License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public + License along with the GNU C Library; see the file COPYING.LIB. If not, + write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. */ + +#include <math.h> + +#include "math_private.h" + + +static const double zero = 0.0; + + +double +__remquo (double x, double y, int *quo) +{ + int32_t hx,hy; + u_int32_t sx,lx,ly; + int cquo, qs; + + EXTRACT_WORDS (hx, lx, x); + EXTRACT_WORDS (hy, ly, y); + sx = hx & 0x80000000; + qs = sx ^ (hy & 0x80000000); + hy &= 0x7fffffff; + hx &= 0x7fffffff; + + /* Purge off exception values. */ + if ((hy | ly) == 0) + return (x * y) / (x * y); /* y = 0 */ + if ((hx >= 0x7ff00000) /* x not finite */ + || ((hy >= 0x7ff00000) /* p is NaN */ + && (((hy - 0x7ff00000) | ly) != 0))) + return (x * y) / (x * y); + + if (hy <= 0x7fbfffff) + x = __ieee754_fmod (x, 8 * y); /* now x < 8y */ + + if (((hx - hy) | (lx - ly)) == 0) + { + *quo = qs ? -1 : 1; + return zero * x; + } + + x = fabs (x); + y = fabs (y); + cquo = 0; + + if (x >= 4 * y) + { + x -= 4 * y; + cquo += 4; + } + if (x >= 2 * y) + { + x -= 2 * y; + cquo += 2; + } + + if (hy < 0x00200000) + { + if (x + x > y) + { + x -= y; + ++cquo; + if (x + x >= y) + { + x -= y; + ++cquo; + } + } + } + else + { + double y_half = 0.5 * y; + if (x > y_half) + { + x -= y; + ++cquo; + if (x >= y_half) + { + x -= y; + ++cquo; + } + } + } + + *quo = qs ? -cquo : cquo; + + if (sx) + x = -x; + return x; +} +weak_alias (__remquo, remquo) +#ifdef NO_LONG_DOUBLE +strong_alias (__remquo, __remquol) +weak_alias (__remquo, remquol) +#endif |