mirror of
https://sourceware.org/git/glibc.git
synced 2024-12-25 12:11:10 +00:00
44 lines
1.3 KiB
C
44 lines
1.3 KiB
C
/* Copyright (C) 2007 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
Contributed by Richard Henderson.
|
|
|
|
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
|
|
<http://www.gnu.org/licenses/>. */
|
|
|
|
#include <math.h>
|
|
|
|
|
|
float
|
|
__roundf (float x)
|
|
{
|
|
const float almost_half = 0x1.fffffep-2;
|
|
const float two23 = 0x1.0p23;
|
|
float r, tmp;
|
|
|
|
__asm (
|
|
#ifdef _IEEE_FP_INEXACT
|
|
"adds/suic %2, %3, %1\n\tsubs/suic %1, %3, %0"
|
|
#else
|
|
"adds/suc %2, %3, %1\n\tsubs/suc %1, %3, %0"
|
|
#endif
|
|
: "=&f"(r), "=&f"(tmp)
|
|
: "f"(fabsf (x) + almost_half), "f"(two23));
|
|
|
|
/* round(-0) == -0, and in general we'll always have the same
|
|
sign as our input. */
|
|
return copysignf (r, x);
|
|
}
|
|
|
|
weak_alias (__roundf, roundf)
|