1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
|
/* Copyright (C) 1998, 1999, 2000, 2006, 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, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <math.h>
#include <math_ldbl_opt.h>
/* Use the -inf rounding mode conversion instructions to implement
floor. We note when the exponent is large enough that the value
must be integral, as this avoids unpleasant integer overflows. */
double
__floor (double x)
{
double two52 = copysign (0x1.0p52, x);
double r, tmp;
__asm (
#ifdef _IEEE_FP_INEXACT
"addt/suim %2, %3, %1\n\tsubt/suim %1, %3, %0"
#else
"addt/sum %2, %3, %1\n\tsubt/sum %1, %3, %0"
#endif
: "=&f"(r), "=&f"(tmp)
: "f"(x), "f"(two52));
/* floor(-0) == -0, and in general we'll always have the same
sign as our input. */
return copysign (r, x);
}
weak_alias (__floor, floor)
#ifdef NO_LONG_DOUBLE
strong_alias (__floor, __floorl)
weak_alias (__floor, floorl)
#endif
#if LONG_DOUBLE_COMPAT(libm, GLIBC_2_0)
compat_symbol (libm, __floor, floorl, GLIBC_2_0);
#endif
|
