111 lines
2.3 KiB
C
111 lines
2.3 KiB
C
|
/* Compute remainder and a congruent to the quotient.
|
||
|
|
Copyright (C) 1997-2022 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 Lesser General Public
|
||
|
|
License as published by the Free Software Foundation; either
|
||
|
|
version 2.1 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
|
||
|
|
Lesser General Public License for more details.
|
||
|
|
|
||
|
|
You should have received a copy of the GNU Lesser General Public
|
||
|
|
License along with the GNU C Library; if not, see
|
||
|
|
<https://www.gnu.org/licenses/>. */
|
||
|
|
|
||
|
|
#include <math.h>
|
||
|
|
|
||
|
|
#include <math_private.h>
|
||
|
|
|
||
|
|
|
||
|
|
static const float zero = 0.0;
|
||
|
|
#include <libm-alias-float.h>
|
||
|
|
|
||
|
|
|
||
|
|
float
|
||
|
|
__remquof (float x, float y, int *quo)
|
||
|
|
{
|
||
|
|
int32_t hx,hy;
|
||
|
|
uint32_t sx;
|
||
|
|
int cquo, qs;
|
||
|
|
|
||
|
|
GET_FLOAT_WORD (hx, x);
|
||
|
|
GET_FLOAT_WORD (hy, y);
|
||
|
|
sx = hx & 0x80000000;
|
||
|
|
qs = sx ^ (hy & 0x80000000);
|
||
|
|
hy &= 0x7fffffff;
|
||
|
|
hx &= 0x7fffffff;
|
||
|
|
|
||
|
|
/* Purge off exception values. */
|
||
|
|
if (hy == 0)
|
||
|
|
return (x * y) / (x * y); /* y = 0 */
|
||
|
|
if ((hx >= 0x7f800000) /* x not finite */
|
||
|
|
|| (hy > 0x7f800000)) /* y is NaN */
|
||
|
|
return (x * y) / (x * y);
|
||
|
|
|
||
|
|
if (hy <= 0x7dffffff)
|
||
|
|
x = __ieee754_fmodf (x, 8 * y); /* now x < 8y */
|
||
|
|
|
||
|
|
if ((hx - hy) == 0)
|
||
|
|
{
|
||
|
|
*quo = qs ? -1 : 1;
|
||
|
|
return zero * x;
|
||
|
|
}
|
||
|
|
|
||
|
|
x = fabsf (x);
|
||
|
|
y = fabsf (y);
|
||
|
|
cquo = 0;
|
||
|
|
|
||
|
|
if (hy <= 0x7e7fffff && x >= 4 * y)
|
||
|
|
{
|
||
|
|
x -= 4 * y;
|
||
|
|
cquo += 4;
|
||
|
|
}
|
||
|
|
if (hy <= 0x7effffff && x >= 2 * y)
|
||
|
|
{
|
||
|
|
x -= 2 * y;
|
||
|
|
cquo += 2;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (hy < 0x01000000)
|
||
|
|
{
|
||
|
|
if (x + x > y)
|
||
|
|
{
|
||
|
|
x -= y;
|
||
|
|
++cquo;
|
||
|
|
if (x + x >= y)
|
||
|
|
{
|
||
|
|
x -= y;
|
||
|
|
++cquo;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
else
|
||
|
|
{
|
||
|
|
float y_half = 0.5 * y;
|
||
|
|
if (x > y_half)
|
||
|
|
{
|
||
|
|
x -= y;
|
||
|
|
++cquo;
|
||
|
|
if (x >= y_half)
|
||
|
|
{
|
||
|
|
x -= y;
|
||
|
|
++cquo;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
*quo = qs ? -cquo : cquo;
|
||
|
|
|
||
|
|
/* Ensure correct sign of zero result in round-downward mode. */
|
||
|
|
if (x == 0.0f)
|
||
|
|
x = 0.0f;
|
||
|
|
if (sx)
|
||
|
|
x = -x;
|
||
|
|
return x;
|
||
|
|
}
|
||
|
|
libm_alias_float (__remquo, remquo)
|