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authorNorbert Preining <norbert@preining.info>2021-07-04 03:01:24 +0000
committerNorbert Preining <norbert@preining.info>2021-07-04 03:01:24 +0000
commit7994f86ec5e18f9d0d9f90161a2f26dd26d26af7 (patch)
tree88edb7d1a1aed3183a1350202c898716b4ac59ce /macros/texinfo/texinfo/gnulib/lib/intprops.h
parent03fa062b03ce2bb5385f8f30888f94d441fa5cb4 (diff)
CTAN sync 202107040301
Diffstat (limited to 'macros/texinfo/texinfo/gnulib/lib/intprops.h')
-rw-r--r--macros/texinfo/texinfo/gnulib/lib/intprops.h144
1 files changed, 104 insertions, 40 deletions
diff --git a/macros/texinfo/texinfo/gnulib/lib/intprops.h b/macros/texinfo/texinfo/gnulib/lib/intprops.h
index fe67c1f305..2a420ac831 100644
--- a/macros/texinfo/texinfo/gnulib/lib/intprops.h
+++ b/macros/texinfo/texinfo/gnulib/lib/intprops.h
@@ -1,6 +1,6 @@
/* intprops.h -- properties of integer types
- Copyright (C) 2001-2019 Free Software Foundation, Inc.
+ Copyright (C) 2001-2021 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
@@ -48,7 +48,7 @@
/* Minimum and maximum values for integer types and expressions. */
/* The width in bits of the integer type or expression T.
- Do not evaluate T.
+ Do not evaluate T. T must not be a bit-field expression.
Padding bits are not supported; this is checked at compile-time below. */
#define TYPE_WIDTH(t) (sizeof (t) * CHAR_BIT)
@@ -70,7 +70,7 @@
? _GL_SIGNED_INT_MAXIMUM (e) \
: _GL_INT_NEGATE_CONVERT (e, 1))
#define _GL_SIGNED_INT_MAXIMUM(e) \
- (((_GL_INT_CONVERT (e, 1) << (TYPE_WIDTH ((e) + 0) - 2)) - 1) * 2 + 1)
+ (((_GL_INT_CONVERT (e, 1) << (TYPE_WIDTH (+ (e)) - 2)) - 1) * 2 + 1)
/* Work around OpenVMS incompatibility with C99. */
#if !defined LLONG_MAX && defined __INT64_MAX
@@ -86,6 +86,7 @@
/* Does the __typeof__ keyword work? This could be done by
'configure', but for now it's easier to do it by hand. */
#if (2 <= __GNUC__ \
+ || (4 <= __clang_major__) \
|| (1210 <= __IBMC__ && defined __IBM__TYPEOF__) \
|| (0x5110 <= __SUNPRO_C && !__STDC__))
# define _GL_HAVE___TYPEOF__ 1
@@ -94,8 +95,9 @@
#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 it is definitely unsigned. T must not be a bit-field expression.
+ 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
@@ -108,6 +110,8 @@
#define INT_BITS_STRLEN_BOUND(b) (((b) * 146 + 484) / 485)
/* Bound on length of the string representing an integer type or expression T.
+ T must not be a bit-field expression.
+
Subtract 1 for the sign bit if T is signed, and then add 1 more for
a minus sign if needed.
@@ -119,7 +123,7 @@
+ _GL_SIGNED_TYPE_OR_EXPR (t))
/* Bound on buffer size needed to represent an integer type or expression T,
- including the terminating null. */
+ including the terminating null. T must not be a bit-field expression. */
#define INT_BUFSIZE_BOUND(t) (INT_STRLEN_BOUND (t) + 1)
@@ -220,15 +224,39 @@
? (a) < (min) >> (b) \
: (max) >> (b) < (a))
-/* True if __builtin_add_overflow (A, B, P) works when P is non-null. */
-#if 5 <= __GNUC__ && !defined __ICC
-# define _GL_HAS_BUILTIN_OVERFLOW 1
+/* True if __builtin_add_overflow (A, B, P) and __builtin_sub_overflow
+ (A, B, P) work when P is non-null. */
+/* __builtin_{add,sub}_overflow exists but is not reliable in GCC 5.x and 6.x,
+ see <https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98269>. */
+#if 7 <= __GNUC__ && !defined __ICC
+# define _GL_HAS_BUILTIN_ADD_OVERFLOW 1
+#elif defined __has_builtin
+# define _GL_HAS_BUILTIN_ADD_OVERFLOW __has_builtin (__builtin_add_overflow)
#else
-# define _GL_HAS_BUILTIN_OVERFLOW 0
+# define _GL_HAS_BUILTIN_ADD_OVERFLOW 0
#endif
-/* True if __builtin_add_overflow_p (A, B, C) works. */
-#define _GL_HAS_BUILTIN_OVERFLOW_P (7 <= __GNUC__)
+/* True if __builtin_mul_overflow (A, B, P) works when P is non-null. */
+#ifdef __clang__
+/* Work around Clang bug <https://bugs.llvm.org/show_bug.cgi?id=16404>. */
+# define _GL_HAS_BUILTIN_MUL_OVERFLOW 0
+#else
+# define _GL_HAS_BUILTIN_MUL_OVERFLOW _GL_HAS_BUILTIN_ADD_OVERFLOW
+#endif
+
+/* True if __builtin_add_overflow_p (A, B, C) works, and similarly for
+ __builtin_sub_overflow_p and __builtin_mul_overflow_p. */
+#if defined __clang__ || defined __ICC
+/* Clang 11 lacks __builtin_mul_overflow_p, and even if it did it
+ would presumably run afoul of Clang bug 16404. ICC 2021.1's
+ __builtin_add_overflow_p etc. are not treated as integral constant
+ expressions even when all arguments are. */
+# define _GL_HAS_BUILTIN_OVERFLOW_P 0
+#elif defined __has_builtin
+# define _GL_HAS_BUILTIN_OVERFLOW_P __has_builtin (__builtin_mul_overflow_p)
+#else
+# define _GL_HAS_BUILTIN_OVERFLOW_P (7 <= __GNUC__)
+#endif
/* The _GL*_OVERFLOW macros have the same restrictions as the
*_RANGE_OVERFLOW macros, except that they do not assume that operands
@@ -351,43 +379,50 @@
/* Store the low-order bits of A + B, A - B, A * B, respectively, into *R.
Return 1 if the result overflows. See above for restrictions. */
-#define INT_ADD_WRAPV(a, b, r) \
- _GL_INT_OP_WRAPV (a, b, r, +, __builtin_add_overflow, \
- _GL_INT_ADD_RANGE_OVERFLOW)
-#define INT_SUBTRACT_WRAPV(a, b, r) \
- _GL_INT_OP_WRAPV (a, b, r, -, __builtin_sub_overflow, \
- _GL_INT_SUBTRACT_RANGE_OVERFLOW)
-#define INT_MULTIPLY_WRAPV(a, b, r) \
- _GL_INT_OP_WRAPV (a, b, r, *, _GL_BUILTIN_MUL_OVERFLOW, \
- _GL_INT_MULTIPLY_RANGE_OVERFLOW)
-
-/* Like __builtin_mul_overflow, but work around GCC bug 91450. */
-#define _GL_BUILTIN_MUL_OVERFLOW(a, b, r) \
- ((!_GL_SIGNED_TYPE_OR_EXPR (*(r)) && EXPR_SIGNED (a) && EXPR_SIGNED (b) \
- && _GL_INT_MULTIPLY_RANGE_OVERFLOW (a, b, 0, (__typeof__ (*(r))) -1)) \
- ? ((void) __builtin_mul_overflow (a, b, r), 1) \
- : __builtin_mul_overflow (a, b, r))
+#if _GL_HAS_BUILTIN_ADD_OVERFLOW
+# define INT_ADD_WRAPV(a, b, r) __builtin_add_overflow (a, b, r)
+# define INT_SUBTRACT_WRAPV(a, b, r) __builtin_sub_overflow (a, b, r)
+#else
+# define INT_ADD_WRAPV(a, b, r) \
+ _GL_INT_OP_WRAPV (a, b, r, +, _GL_INT_ADD_RANGE_OVERFLOW)
+# define INT_SUBTRACT_WRAPV(a, b, r) \
+ _GL_INT_OP_WRAPV (a, b, r, -, _GL_INT_SUBTRACT_RANGE_OVERFLOW)
+#endif
+#if _GL_HAS_BUILTIN_MUL_OVERFLOW
+# if ((9 < __GNUC__ + (3 <= __GNUC_MINOR__) \
+ || (__GNUC__ == 8 && 4 <= __GNUC_MINOR__)) \
+ && !defined __ICC)
+# define INT_MULTIPLY_WRAPV(a, b, r) __builtin_mul_overflow (a, b, r)
+# else
+ /* Work around GCC bug 91450. */
+# define INT_MULTIPLY_WRAPV(a, b, r) \
+ ((!_GL_SIGNED_TYPE_OR_EXPR (*(r)) && EXPR_SIGNED (a) && EXPR_SIGNED (b) \
+ && _GL_INT_MULTIPLY_RANGE_OVERFLOW (a, b, 0, (__typeof__ (*(r))) -1)) \
+ ? ((void) __builtin_mul_overflow (a, b, r), 1) \
+ : __builtin_mul_overflow (a, b, r))
+# endif
+#else
+# define INT_MULTIPLY_WRAPV(a, b, r) \
+ _GL_INT_OP_WRAPV (a, b, r, *, _GL_INT_MULTIPLY_RANGE_OVERFLOW)
+#endif
/* Nonzero if this compiler has GCC bug 68193 or Clang bug 25390. See:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68193
https://llvm.org/bugs/show_bug.cgi?id=25390
For now, assume all versions of GCC-like compilers generate bogus
- warnings for _Generic. This matters only for older compilers that
- lack __builtin_add_overflow. */
-#if __GNUC__
+ warnings for _Generic. This matters only for compilers that
+ lack relevant builtins. */
+#if __GNUC__ || defined __clang__
# define _GL__GENERIC_BOGUS 1
#else
# define _GL__GENERIC_BOGUS 0
#endif
/* Store the low-order bits of A <op> B into *R, where OP specifies
- the operation. BUILTIN is the builtin operation, and OVERFLOW the
- overflow predicate. Return 1 if the result overflows. See above
- for restrictions. */
-#if _GL_HAS_BUILTIN_OVERFLOW
-# define _GL_INT_OP_WRAPV(a, b, r, op, builtin, overflow) builtin (a, b, r)
-#elif 201112 <= __STDC_VERSION__ && !_GL__GENERIC_BOGUS
-# define _GL_INT_OP_WRAPV(a, b, r, op, builtin, overflow) \
+ the operation and OVERFLOW the overflow predicate. Return 1 if the
+ result overflows. See above for restrictions. */
+#if 201112 <= __STDC_VERSION__ && !_GL__GENERIC_BOGUS
+# define _GL_INT_OP_WRAPV(a, b, r, op, overflow) \
(_Generic \
(*(r), \
signed char: \
@@ -442,7 +477,7 @@
: (*(r) = _GL_INT_OP_WRAPV_VIA_UNSIGNED (a,b,op,unsigned,st), 0)))
# endif
-# define _GL_INT_OP_WRAPV(a, b, r, op, builtin, overflow) \
+# define _GL_INT_OP_WRAPV(a, b, r, op, overflow) \
(sizeof *(r) == sizeof (signed char) \
? _GL_INT_OP_WRAPV_SMALLISH (a, b, r, op, overflow, \
signed char, SCHAR_MIN, SCHAR_MAX, \
@@ -547,7 +582,7 @@
? (EXPR_SIGNED (_GL_INT_CONVERT (tmax, b)) \
? (a) < (tmax) / (b) \
: ((INT_NEGATE_OVERFLOW (b) \
- ? _GL_INT_CONVERT (b, tmax) >> (TYPE_WIDTH (b) - 1) \
+ ? _GL_INT_CONVERT (b, tmax) >> (TYPE_WIDTH (+ (b)) - 1) \
: (tmax) / -(b)) \
<= -1 - (a))) \
: INT_NEGATE_OVERFLOW (_GL_INT_CONVERT (b, tmin)) && (b) == -1 \
@@ -563,4 +598,33 @@
: (tmin) / (a) < (b)) \
: (tmax) / (b) < (a)))
+/* The following macros compute A + B, A - B, and A * B, respectively.
+ If no overflow occurs, they set *R to the result and return 1;
+ otherwise, they return 0 and may modify *R.
+
+ Example usage:
+
+ long int result;
+ if (INT_ADD_OK (a, b, &result))
+ printf ("result is %ld\n", result);
+ else
+ printf ("overflow\n");
+
+ A, B, and *R should be integers; they need not be the same type,
+ and they need not be all signed or all unsigned.
+
+ These macros work correctly on all known practical hosts, and do not rely
+ on undefined behavior due to signed arithmetic overflow.
+
+ These macros are not constant expressions.
+
+ These macros may evaluate their arguments zero or multiple times, so the
+ arguments should not have side effects.
+
+ These macros are tuned for B being a constant. */
+
+#define INT_ADD_OK(a, b, r) ! INT_ADD_WRAPV (a, b, r)
+#define INT_SUBTRACT_OK(a, b, r) ! INT_SUBTRACT_WRAPV (a, b, r)
+#define INT_MULTIPLY_OK(a, b, r) ! INT_MULTIPLY_WRAPV (a, b, r)
+
#endif /* _GL_INTPROPS_H */