diff options
author | Clint Adams <clint@debian.org> | 2018-07-04 13:05:31 -0400 |
---|---|---|
committer | Clint Adams <clint@debian.org> | 2018-07-04 13:05:31 -0400 |
commit | 117dcd10d7e04d0dda7668518b8d085027f4d705 (patch) | |
tree | f9612d6268ab16555fb21be04bc7594f9eb6ce4f /lib/intprops.h | |
parent | 1c0d840cad3dc7c951a86c9c128a721e9ebcd2cf (diff) |
New upstream version 4.5
Diffstat (limited to 'lib/intprops.h')
-rw-r--r-- | lib/intprops.h | 81 |
1 files changed, 38 insertions, 43 deletions
diff --git a/lib/intprops.h b/lib/intprops.h index 85ed61f..15e470c 100644 --- a/lib/intprops.h +++ b/lib/intprops.h @@ -1,6 +1,6 @@ /* intprops.h -- properties of integer types - Copyright (C) 2001-2017 Free Software Foundation, Inc. + Copyright (C) 2001-2018 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 @@ -13,7 +13,7 @@ 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/>. */ + along with this program. If not, see <https://www.gnu.org/licenses/>. */ /* Written by Paul Eggert. */ @@ -21,13 +21,12 @@ #define _GL_INTPROPS_H #include <limits.h> -#include <verify.h> /* Return a value with the common real type of E and V and the value of V. */ #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>. */ + <https://lists.gnu.org/r/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, @@ -80,24 +79,7 @@ /* This include file assumes that signed types are two's complement without padding bits; the above macros have undefined behavior otherwise. If this is a problem for you, please let us know how to fix it for your host. - As a sanity check, test the assumption for some signed types that - <limits.h> bounds. */ -verify (TYPE_MINIMUM (signed char) == SCHAR_MIN); -verify (TYPE_MAXIMUM (signed char) == SCHAR_MAX); -verify (TYPE_MINIMUM (short int) == SHRT_MIN); -verify (TYPE_MAXIMUM (short int) == SHRT_MAX); -verify (TYPE_MINIMUM (int) == INT_MIN); -verify (TYPE_MAXIMUM (int) == INT_MAX); -verify (TYPE_MINIMUM (long int) == LONG_MIN); -verify (TYPE_MAXIMUM (long int) == LONG_MAX); -#ifdef LLONG_MAX -verify (TYPE_MINIMUM (long long int) == LLONG_MIN); -verify (TYPE_MAXIMUM (long long int) == LLONG_MAX); -#endif -/* Similarly, sanity-check one ISO/IEC TS 18661-1:2014 macro if defined. */ -#ifdef UINT_WIDTH -verify (TYPE_WIDTH (unsigned int) == UINT_WIDTH); -#endif + This assumption is tested by the intprops-tests module. */ /* Does the __typeof__ keyword work? This could be done by 'configure', but for now it's easier to do it by hand. */ @@ -197,7 +179,7 @@ verify (TYPE_WIDTH (unsigned int) == UINT_WIDTH); /* 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>. */ + <https://lists.gnu.org/r/bug-gnulib/2011-05/msg00401.html>. */ #define INT_MULTIPLY_RANGE_OVERFLOW(a, b, min, max) \ ((b) < 0 \ ? ((a) < 0 \ @@ -237,7 +219,11 @@ verify (TYPE_WIDTH (unsigned int) == UINT_WIDTH); : (max) >> (b) < (a)) /* True if __builtin_add_overflow (A, B, P) works when P is non-null. */ -#define _GL_HAS_BUILTIN_OVERFLOW (5 <= __GNUC__) +#if 5 <= __GNUC__ && !defined __ICC +# define _GL_HAS_BUILTIN_OVERFLOW 1 +#else +# define _GL_HAS_BUILTIN_OVERFLOW 0 +#endif /* True if __builtin_add_overflow_p (A, B, C) works. */ #define _GL_HAS_BUILTIN_OVERFLOW_P (7 <= __GNUC__) @@ -389,10 +375,10 @@ verify (TYPE_WIDTH (unsigned int) == UINT_WIDTH); (_Generic \ (*(r), \ signed char: \ - _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned char, \ + _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \ signed char, SCHAR_MIN, SCHAR_MAX), \ short int: \ - _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned short int, \ + _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \ short int, SHRT_MIN, SHRT_MAX), \ int: \ _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \ @@ -406,10 +392,10 @@ verify (TYPE_WIDTH (unsigned int) == UINT_WIDTH); #else # define _GL_INT_OP_WRAPV(a, b, r, op, builtin, overflow) \ (sizeof *(r) == sizeof (signed char) \ - ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned char, \ + ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \ signed char, SCHAR_MIN, SCHAR_MAX) \ : sizeof *(r) == sizeof (short int) \ - ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned short int, \ + ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \ short int, SHRT_MIN, SHRT_MAX) \ : sizeof *(r) == sizeof (int) \ ? _GL_INT_OP_CALC (a, b, r, op, overflow, unsigned int, \ @@ -431,9 +417,8 @@ verify (TYPE_WIDTH (unsigned int) == UINT_WIDTH); /* Store the low-order bits of A <op> B into *R, where the operation is given by OP. Use the unsigned type UT for calculation to avoid - overflow problems. *R's type is T, with extremal values TMIN and - TMAX. T must be a signed integer type. Return 1 if the result - overflows. */ + overflow problems. *R's type is T, with extrema TMIN and TMAX. + T must be a signed integer type. Return 1 if the result overflows. */ #define _GL_INT_OP_CALC(a, b, r, op, overflow, ut, t, tmin, tmax) \ (sizeof ((a) op (b)) < sizeof (t) \ ? _GL_INT_OP_CALC1 ((t) (a), (t) (b), r, op, overflow, ut, t, tmin, tmax) \ @@ -442,17 +427,27 @@ verify (TYPE_WIDTH (unsigned int) == UINT_WIDTH); ((overflow (a, b) \ || (EXPR_SIGNED ((a) op (b)) && ((a) op (b)) < (tmin)) \ || (tmax) < ((a) op (b))) \ - ? (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t, tmin, tmax), 1) \ - : (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t, tmin, tmax), 0)) - -/* Return A <op> B, where the operation is given by OP. Use the - unsigned type UT for calculation to avoid overflow problems. - Convert the result to type T without overflow by subtracting TMIN - from large values before converting, and adding it afterwards. - Compilers can optimize all the operations except OP. */ -#define _GL_INT_OP_WRAPV_VIA_UNSIGNED(a, b, op, ut, t, tmin, tmax) \ - (((ut) (a) op (ut) (b)) <= (tmax) \ - ? (t) ((ut) (a) op (ut) (b)) \ - : ((t) (((ut) (a) op (ut) (b)) - (tmin)) + (tmin))) + ? (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t), 1) \ + : (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a, b, op, ut, t), 0)) + +/* Return the low-order bits of A <op> B, where the operation is given + by OP. Use the unsigned type UT for calculation to avoid undefined + behavior on signed integer overflow, and convert the result to type T. + UT is at least as wide as T and is no narrower than unsigned int, + T is two's complement, and there is no padding or trap representations. + Assume that converting UT to T yields the low-order bits, as is + done in all known two's-complement C compilers. E.g., see: + https://gcc.gnu.org/onlinedocs/gcc/Integers-implementation.html + + According to the C standard, converting UT to T yields an + implementation-defined result or signal for values outside T's + range. However, code that works around this theoretical problem + runs afoul of a compiler bug in Oracle Studio 12.3 x86. See: + https://lists.gnu.org/r/bug-gnulib/2017-04/msg00049.html + As the compiler bug is real, don't try to work around the + theoretical problem. */ + +#define _GL_INT_OP_WRAPV_VIA_UNSIGNED(a, b, op, ut, t) \ + ((t) ((ut) (a) op (ut) (b))) #endif /* _GL_INTPROPS_H */ |