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Diffstat (limited to 'lib/intprops.h')
| -rw-r--r-- | lib/intprops.h | 319 |
1 files changed, 0 insertions, 319 deletions
diff --git a/lib/intprops.h b/lib/intprops.h deleted file mode 100644 index 2485c78d..00000000 --- a/lib/intprops.h +++ /dev/null @@ -1,319 +0,0 @@ -/* intprops.h -- properties of integer types - - Copyright (C) 2001-2005, 2009-2012 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 3 of the License, 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, see <http://www.gnu.org/licenses/>. */ - -/* Written by Paul Eggert. */ - -#ifndef _GL_INTPROPS_H -#define _GL_INTPROPS_H - -#include <limits.h> - -/* Return an integer value, converted to the same type as the integer - expression E after integer type promotion. V is the unconverted value. */ -#define _GL_INT_CONVERT(e, v) (0 * (e) + (v)) - -/* Act like _GL_INT_CONVERT (E, -V) but work around a bug in IRIX 6.5 cc; see - <http://lists.gnu.org/archive/html/bug-gnulib/2011-05/msg00406.html>. */ -#define _GL_INT_NEGATE_CONVERT(e, v) (0 * (e) - (v)) - -/* 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 signed integer expression E uses two's complement. */ -#define _GL_INT_TWOS_COMPLEMENT(e) (~ _GL_INT_CONVERT (e, 0) == -1) - -/* True if the arithmetic type T is signed. */ -#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1)) - -/* Return 1 if the integer expression E, after integer promotion, has - a signed type. */ -#define _GL_INT_SIGNED(e) (_GL_INT_NEGATE_CONVERT (e, 1) < 0) - - -/* Minimum and maximum values for integer types and expressions. 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. */ - -/* The maximum and minimum values for the integer type T. */ -#define TYPE_MINIMUM(t) \ - ((t) (! TYPE_SIGNED (t) \ - ? (t) 0 \ - : TYPE_SIGNED_MAGNITUDE (t) \ - ? ~ (t) 0 \ - : ~ TYPE_MAXIMUM (t))) -#define TYPE_MAXIMUM(t) \ - ((t) (! TYPE_SIGNED (t) \ - ? (t) -1 \ - : ((((t) 1 << (sizeof (t) * CHAR_BIT - 2)) - 1) * 2 + 1))) - -/* The maximum and minimum values for the type of the expression E, - after integer promotion. E should not have side effects. */ -#define _GL_INT_MINIMUM(e) \ - (_GL_INT_SIGNED (e) \ - ? - _GL_INT_TWOS_COMPLEMENT (e) - _GL_SIGNED_INT_MAXIMUM (e) \ - : _GL_INT_CONVERT (e, 0)) -#define _GL_INT_MAXIMUM(e) \ - (_GL_INT_SIGNED (e) \ - ? _GL_SIGNED_INT_MAXIMUM (e) \ - : _GL_INT_NEGATE_CONVERT (e, 1)) -#define _GL_SIGNED_INT_MAXIMUM(e) \ - (((_GL_INT_CONVERT (e, 1) << (sizeof ((e) + 0) * CHAR_BIT - 2)) - 1) * 2 + 1) - - -/* Return 1 if the __typeof__ keyword works. This could be done by - 'configure', but for now it's easier to do it by hand. */ -#if 2 <= __GNUC__ || 0x5110 <= __SUNPRO_C -# define _GL_HAVE___TYPEOF__ 1 -#else -# define _GL_HAVE___TYPEOF__ 0 -#endif - -/* Return 1 if the integer type or expression T might be signed. Return 0 - if it is definitely unsigned. This macro does not evaluate its argument, - and expands to an integer constant expression. */ -#if _GL_HAVE___TYPEOF__ -# define _GL_SIGNED_TYPE_OR_EXPR(t) TYPE_SIGNED (__typeof__ (t)) -#else -# define _GL_SIGNED_TYPE_OR_EXPR(t) 1 -#endif - -/* Bound on length of the string representing an unsigned integer - value representable in B bits. log10 (2.0) < 146/485. The - smallest value of B where this bound is not tight is 2621. */ -#define INT_BITS_STRLEN_BOUND(b) (((b) * 146 + 484) / 485) - -/* Bound on length of the string representing an integer type or expression T. - Subtract 1 for the sign bit if T is signed, and then add 1 more for - a minus sign if needed. - - Because _GL_SIGNED_TYPE_OR_EXPR sometimes returns 0 when its argument is - signed, this macro may overestimate the true bound by one byte when - applied to unsigned types of size 2, 4, 16, ... bytes. */ -#define INT_STRLEN_BOUND(t) \ - (INT_BITS_STRLEN_BOUND (sizeof (t) * CHAR_BIT \ - - _GL_SIGNED_TYPE_OR_EXPR (t)) \ - + _GL_SIGNED_TYPE_OR_EXPR (t)) - -/* 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) - - -/* Range overflow checks. - - The INT_<op>_RANGE_OVERFLOW macros return 1 if the corresponding C - operators might not yield numerically correct answers due to - arithmetic overflow. They do not rely on undefined or - implementation-defined behavior. Their implementations are simple - and straightforward, but they are a bit harder to use than the - INT_<op>_OVERFLOW macros described below. - - Example usage: - - long int i = ...; - long int j = ...; - if (INT_MULTIPLY_RANGE_OVERFLOW (i, j, LONG_MIN, LONG_MAX)) - printf ("multiply would overflow"); - else - printf ("product is %ld", i * j); - - Restrictions on *_RANGE_OVERFLOW macros: - - These macros do not check for all possible numerical problems or - undefined or unspecified behavior: they do not check for division - by zero, for bad shift counts, or for shifting negative numbers. - - These macros may evaluate their arguments zero or multiple times, - so the arguments should not have side effects. The arithmetic - arguments (including the MIN and MAX arguments) must be of the same - integer type after the usual arithmetic conversions, and the type - must have minimum value MIN and maximum MAX. Unsigned types should - use a zero MIN of the proper type. - - These macros are tuned for constant MIN and MAX. For commutative - operations such as A + B, they are also tuned for constant B. */ - -/* Return 1 if A + B would overflow in [MIN,MAX] arithmetic. - See above for restrictions. */ -#define INT_ADD_RANGE_OVERFLOW(a, b, min, max) \ - ((b) < 0 \ - ? (a) < (min) - (b) \ - : (max) - (b) < (a)) - -/* Return 1 if A - B would overflow in [MIN,MAX] arithmetic. - See above for restrictions. */ -#define INT_SUBTRACT_RANGE_OVERFLOW(a, b, min, max) \ - ((b) < 0 \ - ? (max) + (b) < (a) \ - : (a) < (min) + (b)) - -/* Return 1 if - A would overflow in [MIN,MAX] arithmetic. - See above for restrictions. */ -#define INT_NEGATE_RANGE_OVERFLOW(a, min, max) \ - ((min) < 0 \ - ? (a) < - (max) \ - : 0 < (a)) - -/* Return 1 if A * B would overflow in [MIN,MAX] arithmetic. - See above for restrictions. Avoid && and || as they tickle - bugs in Sun C 5.11 2010/08/13 and other compilers; see - <http://lists.gnu.org/archive/html/bug-gnulib/2011-05/msg00401.html>. */ -#define INT_MULTIPLY_RANGE_OVERFLOW(a, b, min, max) \ - ((b) < 0 \ - ? ((a) < 0 \ - ? (a) < (max) / (b) \ - : (b) == -1 \ - ? 0 \ - : (min) / (b) < (a)) \ - : (b) == 0 \ - ? 0 \ - : ((a) < 0 \ - ? (a) < (min) / (b) \ - : (max) / (b) < (a))) - -/* Return 1 if A / B would overflow in [MIN,MAX] arithmetic. - See above for restrictions. Do not check for division by zero. */ -#define INT_DIVIDE_RANGE_OVERFLOW(a, b, min, max) \ - ((min) < 0 && (b) == -1 && (a) < - (max)) - -/* Return 1 if A % B would overflow in [MIN,MAX] arithmetic. - See above for restrictions. Do not check for division by zero. - Mathematically, % should never overflow, but on x86-like hosts - INT_MIN % -1 traps, and the C standard permits this, so treat this - as an overflow too. */ -#define INT_REMAINDER_RANGE_OVERFLOW(a, b, min, max) \ - INT_DIVIDE_RANGE_OVERFLOW (a, b, min, max) - -/* Return 1 if A << B would overflow in [MIN,MAX] arithmetic. - See above for restrictions. Here, MIN and MAX are for A only, and B need - not be of the same type as the other arguments. The C standard says that - behavior is undefined for shifts unless 0 <= B < wordwidth, and that when - A is negative then A << B has undefined behavior and A >> B has - implementation-defined behavior, but do not check these other - restrictions. */ -#define INT_LEFT_SHIFT_RANGE_OVERFLOW(a, b, min, max) \ - ((a) < 0 \ - ? (a) < (min) >> (b) \ - : (max) >> (b) < (a)) - - -/* The _GL*_OVERFLOW macros have the same restrictions as the - *_RANGE_OVERFLOW macros, except that they do not assume that operands - (e.g., A and B) have the same type as MIN and MAX. Instead, they assume - that the result (e.g., A + B) has that type. */ -#define _GL_ADD_OVERFLOW(a, b, min, max) \ - ((min) < 0 ? INT_ADD_RANGE_OVERFLOW (a, b, min, max) \ - : (a) < 0 ? (b) <= (a) + (b) \ - : (b) < 0 ? (a) <= (a) + (b) \ - : (a) + (b) < (b)) -#define _GL_SUBTRACT_OVERFLOW(a, b, min, max) \ - ((min) < 0 ? INT_SUBTRACT_RANGE_OVERFLOW (a, b, min, max) \ - : (a) < 0 ? 1 \ - : (b) < 0 ? (a) - (b) <= (a) \ - : (a) < (b)) -#define _GL_MULTIPLY_OVERFLOW(a, b, min, max) \ - (((min) == 0 && (((a) < 0 && 0 < (b)) || ((b) < 0 && 0 < (a)))) \ - || INT_MULTIPLY_RANGE_OVERFLOW (a, b, min, max)) -#define _GL_DIVIDE_OVERFLOW(a, b, min, max) \ - ((min) < 0 ? (b) == _GL_INT_NEGATE_CONVERT (min, 1) && (a) < - (max) \ - : (a) < 0 ? (b) <= (a) + (b) - 1 \ - : (b) < 0 && (a) + (b) <= (a)) -#define _GL_REMAINDER_OVERFLOW(a, b, min, max) \ - ((min) < 0 ? (b) == _GL_INT_NEGATE_CONVERT (min, 1) && (a) < - (max) \ - : (a) < 0 ? (a) % (b) != ((max) - (b) + 1) % (b) \ - : (b) < 0 && ! _GL_UNSIGNED_NEG_MULTIPLE (a, b, max)) - -/* Return a nonzero value if A is a mathematical multiple of B, where - A is unsigned, B is negative, and MAX is the maximum value of A's - type. A's type must be the same as (A % B)'s type. Normally (A % - -B == 0) suffices, but things get tricky if -B would overflow. */ -#define _GL_UNSIGNED_NEG_MULTIPLE(a, b, max) \ - (((b) < -_GL_SIGNED_INT_MAXIMUM (b) \ - ? (_GL_SIGNED_INT_MAXIMUM (b) == (max) \ - ? (a) \ - : (a) % (_GL_INT_CONVERT (a, _GL_SIGNED_INT_MAXIMUM (b)) + 1)) \ - : (a) % - (b)) \ - == 0) - - -/* Integer overflow checks. - - The INT_<op>_OVERFLOW macros return 1 if the corresponding C operators - might not yield numerically correct answers due to arithmetic overflow. - They work correctly on all known practical hosts, and do not rely - on undefined behavior due to signed arithmetic overflow. - - Example usage: - - long int i = ...; - long int j = ...; - if (INT_MULTIPLY_OVERFLOW (i, j)) - printf ("multiply would overflow"); - else - printf ("product is %ld", i * j); - - These macros do not check for all possible numerical problems or - undefined or unspecified behavior: they do not check for division - by zero, for bad shift counts, or for shifting negative numbers. - - These macros may evaluate their arguments zero or multiple times, so the - arguments should not have side effects. - - These macros are tuned for their last argument being a constant. - - Return 1 if the integer expressions A * B, A - B, -A, A * B, A / B, - A % B, and A << B would overflow, respectively. */ - -#define INT_ADD_OVERFLOW(a, b) \ - _GL_BINARY_OP_OVERFLOW (a, b, _GL_ADD_OVERFLOW) -#define INT_SUBTRACT_OVERFLOW(a, b) \ - _GL_BINARY_OP_OVERFLOW (a, b, _GL_SUBTRACT_OVERFLOW) -#define INT_NEGATE_OVERFLOW(a) \ - INT_NEGATE_RANGE_OVERFLOW (a, _GL_INT_MINIMUM (a), _GL_INT_MAXIMUM (a)) -#define INT_MULTIPLY_OVERFLOW(a, b) \ - _GL_BINARY_OP_OVERFLOW (a, b, _GL_MULTIPLY_OVERFLOW) -#define INT_DIVIDE_OVERFLOW(a, b) \ - _GL_BINARY_OP_OVERFLOW (a, b, _GL_DIVIDE_OVERFLOW) -#define INT_REMAINDER_OVERFLOW(a, b) \ - _GL_BINARY_OP_OVERFLOW (a, b, _GL_REMAINDER_OVERFLOW) -#define INT_LEFT_SHIFT_OVERFLOW(a, b) \ - INT_LEFT_SHIFT_RANGE_OVERFLOW (a, b, \ - _GL_INT_MINIMUM (a), _GL_INT_MAXIMUM (a)) - -/* Return 1 if the expression A <op> B would overflow, - where OP_RESULT_OVERFLOW (A, B, MIN, MAX) does the actual test, - assuming MIN and MAX are the minimum and maximum for the result type. - Arguments should be free of side effects. */ -#define _GL_BINARY_OP_OVERFLOW(a, b, op_result_overflow) \ - op_result_overflow (a, b, \ - _GL_INT_MINIMUM (0 * (b) + (a)), \ - _GL_INT_MAXIMUM (0 * (b) + (a))) - -#endif /* _GL_INTPROPS_H */ |