diff options
Diffstat (limited to 'sysdeps/m68k/fpu/logb.c')
-rw-r--r-- | sysdeps/m68k/fpu/logb.c | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/sysdeps/m68k/fpu/logb.c b/sysdeps/m68k/fpu/logb.c new file mode 100644 index 0000000..8619c90 --- /dev/null +++ b/sysdeps/m68k/fpu/logb.c @@ -0,0 +1,46 @@ +/* Copyright (C) 1991, 1992, 1993, 1994, 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. */ + +#include <ansidecl.h> +#include <math.h> + +#ifdef __GNUC__ + +/* Return the base 2 signed integral exponent of X. */ + +double +DEFUN(__logb, (x), double x) +{ + if (__isnan (x)) + return x; + if (__isinf (x)) + return fabs (x); + + if (x == 0.0) + asm ("flog2%.x %0, %0" : "=f" (x) : "0" (x)); + else + asm ("fgetexp%.x %0, %0" : "=f" (x) : "0" (x)); + + return x; +} + +weak_alias (__logb, logb) + +#else +#include <sysdeps/ieee754/logb.c> +#endif |