glibc/ports/sysdeps/m68k/m680x0/fpu/e_ilogb.c

48 lines
1.4 KiB
C

/* Copyright (C) 1996-2013 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
<http://www.gnu.org/licenses/>. */
#include <math.h>
#include "mathimpl.h"
#ifndef SUFF
#define SUFF
#endif
#ifndef float_type
#define float_type double
#endif
#define CONCATX(a,b) __CONCAT(a,b)
#define s(name) CONCATX(name,SUFF)
#define m81(func) __m81_u(s(func))
int
s(__ieee754_ilogb) (float_type x)
{
float_type result;
unsigned long x_cond;
x_cond = __m81_test (x);
/* We must return consistent values for zero and NaN. */
if (x_cond & __M81_COND_ZERO)
return FP_ILOGB0;
if (x_cond & (__M81_COND_NAN | __M81_COND_INF))
return FP_ILOGBNAN;
__asm ("fgetexp%.x %1, %0" : "=f" (result) : "f" (x));
return (int) result;
}