mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-28 21:41:08 +00:00
108 lines
3.0 KiB
C
108 lines
3.0 KiB
C
/* Copyright (C) 1992, 1995 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
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., 675 Mass Ave,
|
|
Cambridge, MA 02139, USA. */
|
|
|
|
/*
|
|
* Copyright (c) 1985 Regents of the University of California.
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms are permitted provided
|
|
* that: (1) source distributions retain this entire copyright notice and
|
|
* comment, and (2) distributions including binaries display the following
|
|
* acknowledgement: ``This product includes software developed by the
|
|
* University of California, Berkeley and its contributors'' in the
|
|
* documentation or other materials provided with the distribution and in
|
|
* all advertising materials mentioning features or use of this software.
|
|
* Neither the name of the University nor the names of its contributors may
|
|
* be used to endorse or promote products derived from this software without
|
|
* specific prior written permission.
|
|
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
|
|
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
|
|
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
|
|
*/
|
|
|
|
#include <ansidecl.h>
|
|
#include <math.h>
|
|
#include <float.h>
|
|
#include "ieee754.h"
|
|
|
|
/* Return the remainder of X/Y. */
|
|
double
|
|
DEFUN(__drem, (x, y),
|
|
double x AND double y)
|
|
{
|
|
union ieee754_double ux, uy;
|
|
|
|
ux.d = x;
|
|
uy.d = y;
|
|
#define x ux.d
|
|
#define y uy.d
|
|
|
|
uy.ieee.negative = 0;
|
|
|
|
if (!__finite (x) || y == 0.0)
|
|
return NAN;
|
|
else if (__isnan (y))
|
|
return y;
|
|
else if (__isinf (y))
|
|
return x;
|
|
else if (uy.ieee.exponent <= 1)
|
|
{
|
|
/* Subnormal (or almost subnormal) Y value. */
|
|
double b = __scalb (1.0, 54);
|
|
y *= b;
|
|
x = __drem (x, y);
|
|
x *= b;
|
|
return __drem (x, y) / b;
|
|
}
|
|
else if (y >= 1.7e308 / 2)
|
|
{
|
|
y /= 2;
|
|
x /= 2;
|
|
return __drem (x, y) * 2;
|
|
}
|
|
else
|
|
{
|
|
union ieee754_double a;
|
|
double b;
|
|
unsigned int negative = ux.ieee.negative;
|
|
a.d = y + y;
|
|
b = y / 2;
|
|
ux.ieee.negative = 0;
|
|
while (x > a.d)
|
|
{
|
|
unsigned short int k = ux.ieee.exponent - a.ieee.exponent;
|
|
union ieee754_double tmp;
|
|
tmp.d = a.d;
|
|
tmp.ieee.exponent += k;
|
|
if (x < tmp.d)
|
|
--tmp.ieee.exponent;
|
|
x -= tmp.d;
|
|
}
|
|
if (x > b)
|
|
{
|
|
x -= y;
|
|
if (x >= b)
|
|
x -= y;
|
|
}
|
|
ux.ieee.negative ^= negative;
|
|
return x;
|
|
}
|
|
}
|
|
|
|
weak_alias (__drem, drem)
|