1 /* -*- buffer-read-only: t -*- vi: set ro: */
2 /* DO NOT EDIT! GENERATED AUTOMATICALLY! */
3 /* intprops.h -- properties of integer types
5 Copyright (C) 2001, 2002, 2003, 2004, 2005, 2009, 2010 Free Software
8 This program is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 /* Written by Paul Eggert. */
24 # define GL_INTPROPS_H
28 /* The extra casts in the following macros work around compiler bugs,
29 e.g., in Cray C 5.0.3.0. */
31 /* True if the arithmetic type T is an integer type. bool counts as
33 # define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
35 /* True if negative values of the signed integer type T use two's
36 complement, ones' complement, or signed magnitude representation,
37 respectively. Much GNU code assumes two's complement, but some
38 people like to be portable to all possible C hosts. */
39 # define TYPE_TWOS_COMPLEMENT(t) ((t) ~ (t) 0 == (t) -1)
40 # define TYPE_ONES_COMPLEMENT(t) ((t) ~ (t) 0 == 0)
41 # define TYPE_SIGNED_MAGNITUDE(t) ((t) ~ (t) 0 < (t) -1)
43 /* True if the arithmetic type T is signed. */
44 # define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
46 /* The maximum and minimum values for the integer type T. These
47 macros have undefined behavior if T is signed and has padding bits.
48 If this is a problem for you, please let us know how to fix it for
50 # define TYPE_MINIMUM(t) \
51 ((t) (! TYPE_SIGNED (t) \
53 : TYPE_SIGNED_MAGNITUDE (t) \
55 : ~ (t) 0 << (sizeof (t) * CHAR_BIT - 1)))
56 # define TYPE_MAXIMUM(t) \
57 ((t) (! TYPE_SIGNED (t) \
59 : ~ (~ (t) 0 << (sizeof (t) * CHAR_BIT - 1))))
61 /* Return zero if T can be determined to be an unsigned type.
63 When compiling with GCC, INT_STRLEN_BOUND uses this macro to obtain a
64 tighter bound. Otherwise, it overestimates the true bound by one byte
65 when applied to unsigned types of size 2, 4, 16, ... bytes.
66 The symbol signed_type_or_expr__ is private to this header file. */
68 # define signed_type_or_expr__(t) TYPE_SIGNED (__typeof__ (t))
70 # define signed_type_or_expr__(t) 1
73 /* Bound on length of the string representing an integer type or expression T.
74 Subtract 1 for the sign bit if T is signed; log10 (2.0) < 146/485;
75 add 1 for integer division truncation; add 1 more for a minus sign
77 # define INT_STRLEN_BOUND(t) \
78 ((sizeof (t) * CHAR_BIT - signed_type_or_expr__ (t)) * 146 / 485 \
79 + signed_type_or_expr__ (t) + 1)
81 /* Bound on buffer size needed to represent an integer type or expression T,
82 including the terminating null. */
83 # define INT_BUFSIZE_BOUND(t) (INT_STRLEN_BOUND (t) + 1)
85 #endif /* GL_INTPROPS_H */