/* intprops.h -- properties of integer types
Copyright (C) 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
/* Written by Paul Eggert. */
#include
/* The extra casts in the following macros work around compiler bugs,
e.g., in Cray C 5.0.3.0. */
/* True if the arithmetic type T is an integer type. bool counts as
an integer. */
#define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
/* True if negative values of the signed integer type T use two's
complement, ones' complement, or signed magnitude representation,
respectively. Much GNU code assumes two's complement, but some
people like to be portable to all possible C hosts. */
#define TYPE_TWOS_COMPLEMENT(t) ((t) ~ (t) 0 == (t) -1)
#define TYPE_ONES_COMPLEMENT(t) ((t) ~ (t) 0 == 0)
#define TYPE_SIGNED_MAGNITUDE(t) ((t) ~ (t) 0 < (t) -1)
/* True if the arithmetic type T is signed. */
#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
/* The maximum and minimum values for the integer type T. These
macros have undefined behavior if T is signed and has padding bits.
If this is a problem for you, please let us know how to fix it for
your host. */
#define TYPE_MINIMUM(t) \
((t) (! TYPE_SIGNED (t) \
? (t) 0 \
: TYPE_SIGNED_MAGNITUDE (t) \
? ~ (t) 0 \
: ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1)))
#define TYPE_MAXIMUM(t) \
((t) (! TYPE_SIGNED (t) \
? (t) -1 \
: ~ (~ (t) 0 << (sizeof (t) * CHAR_BIT - 1))))
/* Return zero if T can be determined to be an unsigned type.
Otherwise, return 1.
When compiling with GCC, INT_STRLEN_BOUND uses this macro to obtain a
tighter bound. Otherwise, it overestimates the true bound by one byte
when applied to unsigned types of size 2, 4, 16, ... bytes.
The symbol signed_type_or_expr__ is private to this header file. */
#if __GNUC__ >= 2
# define signed_type_or_expr__(t) TYPE_SIGNED (__typeof__ (t))
#else
# define signed_type_or_expr__(t) 1
#endif
/* Bound on length of the string representing an integer type or expression T.
Subtract 1 for the sign bit if T is signed; log10 (2.0) < 146/485;
add 1 for integer division truncation; add 1 more for a minus sign
if needed. */
#define INT_STRLEN_BOUND(t) \
((sizeof (t) * CHAR_BIT - signed_type_or_expr__ (t)) * 146 / 485 \
+ signed_type_or_expr__ (t) + 1)
/* Bound on buffer size needed to represent an integer type or expression T,
including the terminating null. */
#define INT_BUFSIZE_BOUND(t) (INT_STRLEN_BOUND (t) + 1)