Blame gl/intprops.h

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/* intprops.h -- properties of integer types
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   Copyright (C) 2001-2020 Free Software Foundation, Inc.
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   This program is free software: you can redistribute it and/or modify it
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   under the terms of the GNU Lesser General Public License as published
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   by the Free Software Foundation; either version 2.1 of the License, or
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   (at your option) any later version.
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   This program is distributed in the hope that it will be useful,
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   but WITHOUT ANY WARRANTY; without even the implied warranty of
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   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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   GNU Lesser General Public License for more details.
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   You should have received a copy of the GNU Lesser General Public License
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   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
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/* Written by Paul Eggert.  */
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#ifndef _GL_INTPROPS_H
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#define _GL_INTPROPS_H
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#include <limits.h>
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/* Return a value with the common real type of E and V and the value of V.
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   Do not evaluate E.  */
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#define _GL_INT_CONVERT(e, v) ((1 ? 0 : (e)) + (v))
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/* Act like _GL_INT_CONVERT (E, -V) but work around a bug in IRIX 6.5 cc; see
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   <https://lists.gnu.org/r/bug-gnulib/2011-05/msg00406.html>.  */
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#define _GL_INT_NEGATE_CONVERT(e, v) ((1 ? 0 : (e)) - (v))
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/* The extra casts in the following macros work around compiler bugs,
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   e.g., in Cray C 5.0.3.0.  */
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/* True if the arithmetic type T is an integer type.  bool counts as
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   an integer.  */
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#define TYPE_IS_INTEGER(t) ((t) 1.5 == 1)
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/* True if the real type T is signed.  */
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#define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
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/* Return 1 if the real expression E, after promotion, has a
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   signed or floating type.  Do not evaluate E.  */
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#define EXPR_SIGNED(e) (_GL_INT_NEGATE_CONVERT (e, 1) < 0)
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/* Minimum and maximum values for integer types and expressions.  */
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/* The width in bits of the integer type or expression T.
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   Do not evaluate T.
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   Padding bits are not supported; this is checked at compile-time below.  */
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#define TYPE_WIDTH(t) (sizeof (t) * CHAR_BIT)
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/* The maximum and minimum values for the integer type T.  */
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#define TYPE_MINIMUM(t) ((t) ~ TYPE_MAXIMUM (t))
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#define TYPE_MAXIMUM(t)                                                 \
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  ((t) (! TYPE_SIGNED (t)                                               \
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        ? (t) -1                                                        \
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        : ((((t) 1 << (TYPE_WIDTH (t) - 2)) - 1) * 2 + 1)))
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/* The maximum and minimum values for the type of the expression E,
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   after integer promotion.  E is not evaluated.  */
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#define _GL_INT_MINIMUM(e)                                              \
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  (EXPR_SIGNED (e)                                                      \
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   ? ~ _GL_SIGNED_INT_MAXIMUM (e)                                       \
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   : _GL_INT_CONVERT (e, 0))
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#define _GL_INT_MAXIMUM(e)                                              \
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  (EXPR_SIGNED (e)                                                      \
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   ? _GL_SIGNED_INT_MAXIMUM (e)                                         \
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   : _GL_INT_NEGATE_CONVERT (e, 1))
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#define _GL_SIGNED_INT_MAXIMUM(e)                                       \
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  (((_GL_INT_CONVERT (e, 1) << (TYPE_WIDTH ((e) + 0) - 2)) - 1) * 2 + 1)
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/* Work around OpenVMS incompatibility with C99.  */
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#if !defined LLONG_MAX && defined __INT64_MAX
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# define LLONG_MAX __INT64_MAX
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# define LLONG_MIN __INT64_MIN
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#endif
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/* This include file assumes that signed types are two's complement without
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   padding bits; the above macros have undefined behavior otherwise.
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   If this is a problem for you, please let us know how to fix it for your host.
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   This assumption is tested by the intprops-tests module.  */
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/* Does the __typeof__ keyword work?  This could be done by
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   'configure', but for now it's easier to do it by hand.  */
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#if (2 <= __GNUC__ \
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     || (1210 <= __IBMC__ && defined __IBM__TYPEOF__) \
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     || (0x5110 <= __SUNPRO_C && !__STDC__))
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# define _GL_HAVE___TYPEOF__ 1
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#else
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# define _GL_HAVE___TYPEOF__ 0
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#endif
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/* Return 1 if the integer type or expression T might be signed.  Return 0
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   if it is definitely unsigned.  This macro does not evaluate its argument,
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   and expands to an integer constant expression.  */
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#if _GL_HAVE___TYPEOF__
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# define _GL_SIGNED_TYPE_OR_EXPR(t) TYPE_SIGNED (__typeof__ (t))
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#else
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# define _GL_SIGNED_TYPE_OR_EXPR(t) 1
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#endif
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/* Bound on length of the string representing an unsigned integer
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   value representable in B bits.  log10 (2.0) < 146/485.  The
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   smallest value of B where this bound is not tight is 2621.  */
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#define INT_BITS_STRLEN_BOUND(b) (((b) * 146 + 484) / 485)
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/* Bound on length of the string representing an integer type or expression T.
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   Subtract 1 for the sign bit if T is signed, and then add 1 more for
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   a minus sign if needed.
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   Because _GL_SIGNED_TYPE_OR_EXPR sometimes returns 1 when its argument is
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   unsigned, this macro may overestimate the true bound by one byte when
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   applied to unsigned types of size 2, 4, 16, ... bytes.  */
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#define INT_STRLEN_BOUND(t)                                     \
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  (INT_BITS_STRLEN_BOUND (TYPE_WIDTH (t) - _GL_SIGNED_TYPE_OR_EXPR (t)) \
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   + _GL_SIGNED_TYPE_OR_EXPR (t))
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/* Bound on buffer size needed to represent an integer type or expression T,
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   including the terminating null.  */
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#define INT_BUFSIZE_BOUND(t) (INT_STRLEN_BOUND (t) + 1)
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/* Range overflow checks.
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   The INT_<op>_RANGE_OVERFLOW macros return 1 if the corresponding C
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   operators might not yield numerically correct answers due to
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   arithmetic overflow.  They do not rely on undefined or
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   implementation-defined behavior.  Their implementations are simple
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   and straightforward, but they are a bit harder to use than the
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   INT_<op>_OVERFLOW macros described below.
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   Example usage:
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     long int i = ...;
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     long int j = ...;
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     if (INT_MULTIPLY_RANGE_OVERFLOW (i, j, LONG_MIN, LONG_MAX))
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       printf ("multiply would overflow");
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     else
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       printf ("product is %ld", i * j);
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   Restrictions on *_RANGE_OVERFLOW macros:
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   These macros do not check for all possible numerical problems or
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   undefined or unspecified behavior: they do not check for division
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   by zero, for bad shift counts, or for shifting negative numbers.
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   These macros may evaluate their arguments zero or multiple times,
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   so the arguments should not have side effects.  The arithmetic
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   arguments (including the MIN and MAX arguments) must be of the same
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   integer type after the usual arithmetic conversions, and the type
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   must have minimum value MIN and maximum MAX.  Unsigned types should
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   use a zero MIN of the proper type.
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   These macros are tuned for constant MIN and MAX.  For commutative
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   operations such as A + B, they are also tuned for constant B.  */
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/* Return 1 if A + B would overflow in [MIN,MAX] arithmetic.
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   See above for restrictions.  */
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#define INT_ADD_RANGE_OVERFLOW(a, b, min, max)          \
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  ((b) < 0                                              \
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   ? (a) < (min) - (b)                                  \
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   : (max) - (b) < (a))
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/* Return 1 if A - B would overflow in [MIN,MAX] arithmetic.
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   See above for restrictions.  */
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#define INT_SUBTRACT_RANGE_OVERFLOW(a, b, min, max)     \
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  ((b) < 0                                              \
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   ? (max) + (b) < (a)                                  \
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   : (a) < (min) + (b))
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/* Return 1 if - A would overflow in [MIN,MAX] arithmetic.
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   See above for restrictions.  */
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#define INT_NEGATE_RANGE_OVERFLOW(a, min, max)          \
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  ((min) < 0                                            \
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   ? (a) < - (max)                                      \
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   : 0 < (a))
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/* Return 1 if A * B would overflow in [MIN,MAX] arithmetic.
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   See above for restrictions.  Avoid && and || as they tickle
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   bugs in Sun C 5.11 2010/08/13 and other compilers; see
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   <https://lists.gnu.org/r/bug-gnulib/2011-05/msg00401.html>.  */
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#define INT_MULTIPLY_RANGE_OVERFLOW(a, b, min, max)     \
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  ((b) < 0                                              \
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   ? ((a) < 0                                           \
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      ? (a) < (max) / (b)                               \
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      : (b) == -1                                       \
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      ? 0                                               \
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      : (min) / (b) < (a))                              \
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   : (b) == 0                                           \
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   ? 0                                                  \
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   : ((a) < 0                                           \
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      ? (a) < (min) / (b)                               \
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      : (max) / (b) < (a)))
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/* Return 1 if A / B would overflow in [MIN,MAX] arithmetic.
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   See above for restrictions.  Do not check for division by zero.  */
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#define INT_DIVIDE_RANGE_OVERFLOW(a, b, min, max)       \
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  ((min) < 0 && (b) == -1 && (a) < - (max))
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/* Return 1 if A % B would overflow in [MIN,MAX] arithmetic.
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   See above for restrictions.  Do not check for division by zero.
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   Mathematically, % should never overflow, but on x86-like hosts
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   INT_MIN % -1 traps, and the C standard permits this, so treat this
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   as an overflow too.  */
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#define INT_REMAINDER_RANGE_OVERFLOW(a, b, min, max)    \
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  INT_DIVIDE_RANGE_OVERFLOW (a, b, min, max)
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/* Return 1 if A << B would overflow in [MIN,MAX] arithmetic.
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   See above for restrictions.  Here, MIN and MAX are for A only, and B need
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   not be of the same type as the other arguments.  The C standard says that
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   behavior is undefined for shifts unless 0 <= B < wordwidth, and that when
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   A is negative then A << B has undefined behavior and A >> B has
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   implementation-defined behavior, but do not check these other
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   restrictions.  */
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#define INT_LEFT_SHIFT_RANGE_OVERFLOW(a, b, min, max)   \
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  ((a) < 0                                              \
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   ? (a) < (min) >> (b)                                 \
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   : (max) >> (b) < (a))
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/* True if __builtin_add_overflow (A, B, P) and __builtin_sub_overflow
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   (A, B, P) work when P is non-null.  */
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#if 5 <= __GNUC__ && !defined __ICC
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# define _GL_HAS_BUILTIN_ADD_OVERFLOW 1
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#elif defined __has_builtin
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# define _GL_HAS_BUILTIN_ADD_OVERFLOW __has_builtin (__builtin_add_overflow)
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#else
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# define _GL_HAS_BUILTIN_ADD_OVERFLOW 0
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#endif
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/* True if __builtin_mul_overflow (A, B, P) works when P is non-null.  */
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#ifdef __clang__
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/* Work around Clang bug <https://bugs.llvm.org/show_bug.cgi?id=16404>.  */
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# define _GL_HAS_BUILTIN_MUL_OVERFLOW 0
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#else
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# define _GL_HAS_BUILTIN_MUL_OVERFLOW _GL_HAS_BUILTIN_ADD_OVERFLOW
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#endif
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/* True if __builtin_add_overflow_p (A, B, C) works, and similarly for
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   __builtin_mul_overflow_p and __builtin_mul_overflow_p.  */
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#define _GL_HAS_BUILTIN_OVERFLOW_P (7 <= __GNUC__)
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/* The _GL*_OVERFLOW macros have the same restrictions as the
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   *_RANGE_OVERFLOW macros, except that they do not assume that operands
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   (e.g., A and B) have the same type as MIN and MAX.  Instead, they assume
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   that the result (e.g., A + B) has that type.  */
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#if _GL_HAS_BUILTIN_OVERFLOW_P
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# define _GL_ADD_OVERFLOW(a, b, min, max)                               \
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   __builtin_add_overflow_p (a, b, (__typeof__ ((a) + (b))) 0)
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# define _GL_SUBTRACT_OVERFLOW(a, b, min, max)                          \
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   __builtin_sub_overflow_p (a, b, (__typeof__ ((a) - (b))) 0)
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# define _GL_MULTIPLY_OVERFLOW(a, b, min, max)                          \
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   __builtin_mul_overflow_p (a, b, (__typeof__ ((a) * (b))) 0)
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#else
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# define _GL_ADD_OVERFLOW(a, b, min, max)                                \
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   ((min) < 0 ? INT_ADD_RANGE_OVERFLOW (a, b, min, max)                  \
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    : (a) < 0 ? (b) <= (a) + (b)                                         \
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    : (b) < 0 ? (a) <= (a) + (b)                                         \
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    : (a) + (b) < (b))
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# define _GL_SUBTRACT_OVERFLOW(a, b, min, max)                           \
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   ((min) < 0 ? INT_SUBTRACT_RANGE_OVERFLOW (a, b, min, max)             \
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    : (a) < 0 ? 1                                                        \
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    : (b) < 0 ? (a) - (b) <= (a)                                         \
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    : (a) < (b))
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# define _GL_MULTIPLY_OVERFLOW(a, b, min, max)                           \
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   (((min) == 0 && (((a) < 0 && 0 < (b)) || ((b) < 0 && 0 < (a))))       \
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    || INT_MULTIPLY_RANGE_OVERFLOW (a, b, min, max))
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#endif
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#define _GL_DIVIDE_OVERFLOW(a, b, min, max)                             \
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  ((min) < 0 ? (b) == _GL_INT_NEGATE_CONVERT (min, 1) && (a) < - (max)  \
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   : (a) < 0 ? (b) <= (a) + (b) - 1                                     \
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   : (b) < 0 && (a) + (b) <= (a))
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#define _GL_REMAINDER_OVERFLOW(a, b, min, max)                          \
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  ((min) < 0 ? (b) == _GL_INT_NEGATE_CONVERT (min, 1) && (a) < - (max)  \
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   : (a) < 0 ? (a) % (b) != ((max) - (b) + 1) % (b)                     \
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   : (b) < 0 && ! _GL_UNSIGNED_NEG_MULTIPLE (a, b, max))
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/* Return a nonzero value if A is a mathematical multiple of B, where
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   A is unsigned, B is negative, and MAX is the maximum value of A's
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   type.  A's type must be the same as (A % B)'s type.  Normally (A %
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   -B == 0) suffices, but things get tricky if -B would overflow.  */
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#define _GL_UNSIGNED_NEG_MULTIPLE(a, b, max)                            \
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  (((b) < -_GL_SIGNED_INT_MAXIMUM (b)                                   \
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    ? (_GL_SIGNED_INT_MAXIMUM (b) == (max)                              \
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       ? (a)                                                            \
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       : (a) % (_GL_INT_CONVERT (a, _GL_SIGNED_INT_MAXIMUM (b)) + 1))   \
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    : (a) % - (b))                                                      \
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   == 0)
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/* Check for integer overflow, and report low order bits of answer.
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   The INT_<op>_OVERFLOW macros return 1 if the corresponding C operators
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   might not yield numerically correct answers due to arithmetic overflow.
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   The INT_<op>_WRAPV macros compute the low-order bits of the sum,
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   difference, and product of two C integers, and return 1 if these
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   low-order bits are not numerically correct.
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   These macros work correctly on all known practical hosts, and do not rely
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   on undefined behavior due to signed arithmetic overflow.
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   Example usage, assuming A and B are long int:
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     if (INT_MULTIPLY_OVERFLOW (a, b))
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       printf ("result would overflow\n");
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     else
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       printf ("result is %ld (no overflow)\n", a * b);
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   Example usage with WRAPV flavor:
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     long int result;
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     bool overflow = INT_MULTIPLY_WRAPV (a, b, &result);
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     printf ("result is %ld (%s)\n", result,
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             overflow ? "after overflow" : "no overflow");
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   Restrictions on these macros:
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   These macros do not check for all possible numerical problems or
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   undefined or unspecified behavior: they do not check for division
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   by zero, for bad shift counts, or for shifting negative numbers.
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   These macros may evaluate their arguments zero or multiple times, so the
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   arguments should not have side effects.
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   The WRAPV macros are not constant expressions.  They support only
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   +, binary -, and *.  Because the WRAPV macros convert the result,
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   they report overflow in different circumstances than the OVERFLOW
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   macros do.
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   These macros are tuned for their last input argument being a constant.
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   Return 1 if the integer expressions A * B, A - B, -A, A * B, A / B,
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   A % B, and A << B would overflow, respectively.  */
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#define INT_ADD_OVERFLOW(a, b) \
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  _GL_BINARY_OP_OVERFLOW (a, b, _GL_ADD_OVERFLOW)
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#define INT_SUBTRACT_OVERFLOW(a, b) \
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  _GL_BINARY_OP_OVERFLOW (a, b, _GL_SUBTRACT_OVERFLOW)
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#if _GL_HAS_BUILTIN_OVERFLOW_P
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# define INT_NEGATE_OVERFLOW(a) INT_SUBTRACT_OVERFLOW (0, a)
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#else
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# define INT_NEGATE_OVERFLOW(a) \
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   INT_NEGATE_RANGE_OVERFLOW (a, _GL_INT_MINIMUM (a), _GL_INT_MAXIMUM (a))
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#endif
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#define INT_MULTIPLY_OVERFLOW(a, b) \
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  _GL_BINARY_OP_OVERFLOW (a, b, _GL_MULTIPLY_OVERFLOW)
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#define INT_DIVIDE_OVERFLOW(a, b) \
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  _GL_BINARY_OP_OVERFLOW (a, b, _GL_DIVIDE_OVERFLOW)
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#define INT_REMAINDER_OVERFLOW(a, b) \
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  _GL_BINARY_OP_OVERFLOW (a, b, _GL_REMAINDER_OVERFLOW)
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#define INT_LEFT_SHIFT_OVERFLOW(a, b) \
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  INT_LEFT_SHIFT_RANGE_OVERFLOW (a, b, \
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                                 _GL_INT_MINIMUM (a), _GL_INT_MAXIMUM (a))
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/* Return 1 if the expression A <op> B would overflow,
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   where OP_RESULT_OVERFLOW (A, B, MIN, MAX) does the actual test,
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   assuming MIN and MAX are the minimum and maximum for the result type.
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   Arguments should be free of side effects.  */
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#define _GL_BINARY_OP_OVERFLOW(a, b, op_result_overflow)        \
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  op_result_overflow (a, b,                                     \
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                      _GL_INT_MINIMUM (_GL_INT_CONVERT (a, b)), \
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                      _GL_INT_MAXIMUM (_GL_INT_CONVERT (a, b)))
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/* Store the low-order bits of A + B, A - B, A * B, respectively, into *R.
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   Return 1 if the result overflows.  See above for restrictions.  */
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#if _GL_HAS_BUILTIN_ADD_OVERFLOW
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# define INT_ADD_WRAPV(a, b, r) __builtin_add_overflow (a, b, r)
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# define INT_SUBTRACT_WRAPV(a, b, r) __builtin_sub_overflow (a, b, r)
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#else
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# define INT_ADD_WRAPV(a, b, r) \
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   _GL_INT_OP_WRAPV (a, b, r, +, _GL_INT_ADD_RANGE_OVERFLOW)
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# define INT_SUBTRACT_WRAPV(a, b, r) \
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   _GL_INT_OP_WRAPV (a, b, r, -, _GL_INT_SUBTRACT_RANGE_OVERFLOW)
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#endif
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#if _GL_HAS_BUILTIN_MUL_OVERFLOW
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# if (9 < __GNUC__ + (3 <= __GNUC_MINOR__) \
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      || (__GNUC__ == 8 && 4 <= __GNUC_MINOR__))
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#  define INT_MULTIPLY_WRAPV(a, b, r) __builtin_mul_overflow (a, b, r)
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# else
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   /* Work around GCC bug 91450.  */
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#  define INT_MULTIPLY_WRAPV(a, b, r) \
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    ((!_GL_SIGNED_TYPE_OR_EXPR (*(r)) && EXPR_SIGNED (a) && EXPR_SIGNED (b) \
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      && _GL_INT_MULTIPLY_RANGE_OVERFLOW (a, b, 0, (__typeof__ (*(r))) -1)) \
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     ? ((void) __builtin_mul_overflow (a, b, r), 1) \
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     : __builtin_mul_overflow (a, b, r))
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# endif
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#else
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# define INT_MULTIPLY_WRAPV(a, b, r) \
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   _GL_INT_OP_WRAPV (a, b, r, *, _GL_INT_MULTIPLY_RANGE_OVERFLOW)
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#endif
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/* Nonzero if this compiler has GCC bug 68193 or Clang bug 25390.  See:
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   https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68193
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   https://llvm.org/bugs/show_bug.cgi?id=25390
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   For now, assume all versions of GCC-like compilers generate bogus
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   warnings for _Generic.  This matters only for compilers that
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   lack relevant builtins.  */
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#if __GNUC__
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# define _GL__GENERIC_BOGUS 1
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#else
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# define _GL__GENERIC_BOGUS 0
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#endif
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/* Store the low-order bits of A <op> B into *R, where OP specifies
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   the operation and OVERFLOW the overflow predicate.  Return 1 if the
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   result overflows.  See above for restrictions.  */
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#if 201112 <= __STDC_VERSION__ && !_GL__GENERIC_BOGUS
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# define _GL_INT_OP_WRAPV(a, b, r, op, overflow) \
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   (_Generic \
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    (*(r), \
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     signed char: \
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       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
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                        signed char, SCHAR_MIN, SCHAR_MAX), \
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     unsigned char: \
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       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
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                        unsigned char, 0, UCHAR_MAX), \
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     short int: \
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       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
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                        short int, SHRT_MIN, SHRT_MAX), \
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     unsigned short int: \
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       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
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                        unsigned short int, 0, USHRT_MAX), \
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     int: \
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       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
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                        int, INT_MIN, INT_MAX), \
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     unsigned int: \
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       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
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                        unsigned int, 0, UINT_MAX), \
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     long int: \
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       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
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                        long int, LONG_MIN, LONG_MAX), \
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     unsigned long int: \
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       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
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                        unsigned long int, 0, ULONG_MAX), \
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     long long int: \
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       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long long int, \
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                        long long int, LLONG_MIN, LLONG_MAX), \
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     unsigned long long int: \
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       _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long long int, \
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                        unsigned long long int, 0, ULLONG_MAX)))
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#else
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/* Store the low-order bits of A <op> B into *R, where OP specifies
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   the operation and OVERFLOW the overflow predicate.  If *R is
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   signed, its type is ST with bounds SMIN..SMAX; otherwise its type
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   is UT with bounds U..UMAX.  ST and UT are narrower than int.
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   Return 1 if the result overflows.  See above for restrictions.  */
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# if _GL_HAVE___TYPEOF__
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#  define _GL_INT_OP_WRAPV_SMALLISH(a,b,r,op,overflow,st,smin,smax,ut,umax) \
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    (TYPE_SIGNED (__typeof__ (*(r))) \
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     ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, st, smin, smax) \
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     : _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, ut, 0, umax))
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# else
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#  define _GL_INT_OP_WRAPV_SMALLISH(a,b,r,op,overflow,st,smin,smax,ut,umax) \
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    (overflow (a, b, smin, smax) \
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     ? (overflow (a, b, 0, umax) \
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        ? (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a,b,op,unsigned,st), 1) \
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        : (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a,b,op,unsigned,st)) < 0) \
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     : (overflow (a, b, 0, umax) \
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        ? (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a,b,op,unsigned,st)) >= 0 \
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        : (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a,b,op,unsigned,st), 0)))
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# endif
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# define _GL_INT_OP_WRAPV(a, b, r, op, overflow) \
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   (sizeof *(r) == sizeof (signed char) \
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    ? _GL_INT_OP_WRAPV_SMALLISH (a, b, r, op, overflow, \
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                                 signed char, SCHAR_MIN, SCHAR_MAX, \
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                                 unsigned char, UCHAR_MAX) \
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    : sizeof *(r) == sizeof (short int) \
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    ? _GL_INT_OP_WRAPV_SMALLISH (a, b, r, op, overflow, \
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                                 short int, SHRT_MIN, SHRT_MAX, \
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                                 unsigned short int, USHRT_MAX) \
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    : sizeof *(r) == sizeof (int) \
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    ? (EXPR_SIGNED (*(r)) \
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       ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
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                          int, INT_MIN, INT_MAX) \
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       : _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \
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                          unsigned int, 0, UINT_MAX)) \
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    : _GL_INT_OP_WRAPV_LONGISH(a, b, r, op, overflow))
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# ifdef LLONG_MAX
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#  define _GL_INT_OP_WRAPV_LONGISH(a, b, r, op, overflow) \
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    (sizeof *(r) == sizeof (long int) \
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     ? (EXPR_SIGNED (*(r)) \
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        ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
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                           long int, LONG_MIN, LONG_MAX) \
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        : _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
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                           unsigned long int, 0, ULONG_MAX)) \
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     : (EXPR_SIGNED (*(r)) \
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        ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long long int, \
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                           long long int, LLONG_MIN, LLONG_MAX) \
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        : _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long long int, \
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                           unsigned long long int, 0, ULLONG_MAX)))
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# else
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#  define _GL_INT_OP_WRAPV_LONGISH(a, b, r, op, overflow) \
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    (EXPR_SIGNED (*(r)) \
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     ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
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                        long int, LONG_MIN, LONG_MAX) \
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     : _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned long int, \
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                        unsigned long int, 0, ULONG_MAX))
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# endif
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#endif
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/* Store the low-order bits of A <op> B into *R, where the operation
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   is given by OP.  Use the unsigned type UT for calculation to avoid
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   overflow problems.  *R's type is T, with extrema TMIN and TMAX.
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   T must be a signed integer type.  Return 1 if the result overflows.  */
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#define _GL_INT_OP_CALC(a, b, r, op, overflow, ut, t, tmin, tmax) \
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  (overflow (a, b, tmin, tmax) \
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   ? (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t), 1) \
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   : (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t), 0))
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/* Return the low-order bits of A <op> B, where the operation is given
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   by OP.  Use the unsigned type UT for calculation to avoid undefined
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   behavior on signed integer overflow, and convert the result to type T.
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   UT is at least as wide as T and is no narrower than unsigned int,
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   T is two's complement, and there is no padding or trap representations.
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   Assume that converting UT to T yields the low-order bits, as is
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   done in all known two's-complement C compilers.  E.g., see:
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   https://gcc.gnu.org/onlinedocs/gcc/Integers-implementation.html
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   According to the C standard, converting UT to T yields an
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   implementation-defined result or signal for values outside T's
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   range.  However, code that works around this theoretical problem
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   runs afoul of a compiler bug in Oracle Studio 12.3 x86.  See:
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   https://lists.gnu.org/r/bug-gnulib/2017-04/msg00049.html
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   As the compiler bug is real, don't try to work around the
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   theoretical problem.  */
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#define _GL_INT_OP_WRAPV_VIA_UNSIGNED(a, b, op, ut, t) \
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  ((t) ((ut) (a) op (ut) (b)))
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/* Return true if the numeric values A + B, A - B, A * B fall outside
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   the range TMIN..TMAX.  Arguments should be integer expressions
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   without side effects.  TMIN should be signed and nonpositive.
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   TMAX should be positive, and should be signed unless TMIN is zero.  */
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#define _GL_INT_ADD_RANGE_OVERFLOW(a, b, tmin, tmax) \
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  ((b) < 0 \
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   ? (((tmin) \
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       ? ((EXPR_SIGNED (_GL_INT_CONVERT (a, (tmin) - (b))) || (b) < (tmin)) \
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          && (a) < (tmin) - (b)) \
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       : (a) <= -1 - (b)) \
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      || ((EXPR_SIGNED (a) ? 0 <= (a) : (tmax) < (a)) && (tmax) < (a) + (b))) \
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   : (a) < 0 \
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   ? (((tmin) \
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       ? ((EXPR_SIGNED (_GL_INT_CONVERT (b, (tmin) - (a))) || (a) < (tmin)) \
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          && (b) < (tmin) - (a)) \
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       : (b) <= -1 - (a)) \
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      || ((EXPR_SIGNED (_GL_INT_CONVERT (a, b)) || (tmax) < (b)) \
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          && (tmax) < (a) + (b))) \
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   : (tmax) < (b) || (tmax) - (b) < (a))
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#define _GL_INT_SUBTRACT_RANGE_OVERFLOW(a, b, tmin, tmax) \
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  (((a) < 0) == ((b) < 0) \
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   ? ((a) < (b) \
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      ? !(tmin) || -1 - (tmin) < (b) - (a) - 1 \
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      : (tmax) < (a) - (b)) \
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   : (a) < 0 \
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   ? ((!EXPR_SIGNED (_GL_INT_CONVERT ((a) - (tmin), b)) && (a) - (tmin) < 0) \
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      || (a) - (tmin) < (b)) \
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   : ((! (EXPR_SIGNED (_GL_INT_CONVERT (tmax, b)) \
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          && EXPR_SIGNED (_GL_INT_CONVERT ((tmax) + (b), a))) \
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       && (tmax) <= -1 - (b)) \
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      || (tmax) + (b) < (a)))
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#define _GL_INT_MULTIPLY_RANGE_OVERFLOW(a, b, tmin, tmax) \
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  ((b) < 0 \
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   ? ((a) < 0 \
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      ? (EXPR_SIGNED (_GL_INT_CONVERT (tmax, b)) \
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         ? (a) < (tmax) / (b) \
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         : ((INT_NEGATE_OVERFLOW (b) \
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             ? _GL_INT_CONVERT (b, tmax) >> (TYPE_WIDTH (b) - 1) \
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             : (tmax) / -(b)) \
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            <= -1 - (a))) \
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      : INT_NEGATE_OVERFLOW (_GL_INT_CONVERT (b, tmin)) && (b) == -1 \
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      ? (EXPR_SIGNED (a) \
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         ? 0 < (a) + (tmin) \
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         : 0 < (a) && -1 - (tmin) < (a) - 1) \
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      : (tmin) / (b) < (a)) \
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   : (b) == 0 \
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   ? 0 \
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   : ((a) < 0 \
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      ? (INT_NEGATE_OVERFLOW (_GL_INT_CONVERT (a, tmin)) && (a) == -1 \
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         ? (EXPR_SIGNED (b) ? 0 < (b) + (tmin) : -1 - (tmin) < (b) - 1) \
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         : (tmin) / (a) < (b)) \
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      : (tmax) / (b) < (a)))
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#endif /* _GL_INTPROPS_H */