These patches are modest reworkings of previous patches.
The patch for char_traits was pretty much approved already. But in response to
a comment from François I at least added __copy_backwards, and used ptrdiff_t
instead of size_t parameters and I put all the mem* wrappers in a __detail
namespace. I didn't change some names. I know Jonathan wanted a bikeshed
discussion.
For the constexpr iterators I was asked to simplify the testsuite. Done.
These would finish p1032 except for std::string::copy which I think should wait
behind the rest of constexpr string.
Another thing I need to do is respond to the SG-10 changes for the p1032
macros. There's one thing that bothers me still in light of the policy that
these macros are names __cpp_lib_constexpr_HEADER: We sill have
__cpp_lib_constexpr_algorithmS in <algorithm>.
OK if these pass final retesting?
2019-12-10 Edward Smith-Rowland <[email protected]>
Implement the char_traits and string_view part of C++20 p1032 Misc.
constexpr bits.
* include/bits/char_traits.h (move, copy, assign): Constexpr.
* include/bits/stl_algobase.h (__memcpy, __memset): New.
* include/ext/pod_char_traits.h (from, to, operator==, operator<)
(assign, eq, lt, compare, length, find, move, copy, assign)
(to_char_type, to_int_type, eq_int_type, eof, not_eof):
Make these constespr for appropriate standards.
* include/std/string_view (copy): Constexpr.
* testsuite/21_strings/char_traits/requirements/char/constexpr.cc: New test.
* testsuite/21_strings/char_traits/requirements/wchar_t/constexpr.cc: New test.
* testsuite/21_strings/basic_string_view/operations/copy/char/constexpr.cc: New test.
* testsuite/21_strings/basic_string_view/operations/copy/wchar_t/constexpr.cc: New test.
Index: include/bits/char_traits.h
===================================================================
--- include/bits/char_traits.h (revision 279174)
+++ include/bits/char_traits.h (working copy)
@@ -113,13 +113,13 @@
static _GLIBCXX14_CONSTEXPR const char_type*
find(const char_type* __s, std::size_t __n, const char_type& __a);
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
move(char_type* __s1, const char_type* __s2, std::size_t __n);
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
copy(char_type* __s1, const char_type* __s2, std::size_t __n);
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
assign(char_type* __s, std::size_t __n, char_type __a);
static _GLIBCXX_CONSTEXPR char_type
@@ -179,18 +179,18 @@
}
template<typename _CharT>
- typename char_traits<_CharT>::char_type*
+ _GLIBCXX20_CONSTEXPR typename char_traits<_CharT>::char_type*
char_traits<_CharT>::
move(char_type* __s1, const char_type* __s2, std::size_t __n)
{
if (__n == 0)
return __s1;
- return static_cast<_CharT*>(__builtin_memmove(__s1, __s2,
- __n * sizeof(char_type)));
+ return static_cast<_CharT*>
+ (std::__detail::__memmove<true>(__s1, __s2, __n));
}
template<typename _CharT>
- typename char_traits<_CharT>::char_type*
+ _GLIBCXX20_CONSTEXPR typename char_traits<_CharT>::char_type*
char_traits<_CharT>::
copy(char_type* __s1, const char_type* __s2, std::size_t __n)
{
@@ -200,7 +200,7 @@
}
template<typename _CharT>
- typename char_traits<_CharT>::char_type*
+ _GLIBCXX20_CONSTEXPR typename char_traits<_CharT>::char_type*
char_traits<_CharT>::
assign(char_type* __s, std::size_t __n, char_type __a)
{
@@ -349,28 +349,30 @@
return static_cast<const char_type*>(__builtin_memchr(__s, __a, __n));
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
move(char_type* __s1, const char_type* __s2, size_t __n)
{
if (__n == 0)
return __s1;
- return static_cast<char_type*>(__builtin_memmove(__s1, __s2, __n));
+ return static_cast<char_type*>
+ (std::__detail::__memmove<true>(__s1, __s2, __n));
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
copy(char_type* __s1, const char_type* __s2, size_t __n)
{
if (__n == 0)
return __s1;
- return static_cast<char_type*>(__builtin_memcpy(__s1, __s2, __n));
+ return static_cast<char_type*>(
+ std::__detail::__memcpy(__s1, __s2, __n));
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
assign(char_type* __s, size_t __n, char_type __a)
{
if (__n == 0)
return __s;
- return static_cast<char_type*>(__builtin_memset(__s, __a, __n));
+ return static_cast<char_type*>(std::__detail::__memset(__s, __a, __n));
}
static _GLIBCXX_CONSTEXPR char_type
@@ -458,27 +460,45 @@
return wmemchr(__s, __a, __n);
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
move(char_type* __s1, const char_type* __s2, size_t __n)
{
if (__n == 0)
return __s1;
+#ifdef __cpp_lib_is_constant_evaluated
+ if (std::is_constant_evaluated())
+ return static_cast<char_type*>
+ (std::__detail::__memmove<true>(__s1, __s2, __n));
+ else
+#endif
return wmemmove(__s1, __s2, __n);
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
copy(char_type* __s1, const char_type* __s2, size_t __n)
{
if (__n == 0)
return __s1;
+#ifdef __cpp_lib_is_constant_evaluated
+ if (std::is_constant_evaluated())
+ return static_cast<char_type*>(
+ std::__detail::__memcpy(__s1, __s2, __n));
+ else
+#endif
return wmemcpy(__s1, __s2, __n);
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
assign(char_type* __s, size_t __n, char_type __a)
{
if (__n == 0)
return __s;
+#ifdef __cpp_lib_is_constant_evaluated
+ if (std::is_constant_evaluated())
+ return static_cast<char_type*>(
+ std::__detail::__memset(__s, __a, __n));
+ else
+#endif
return wmemset(__s, __a, __n);
}
@@ -567,28 +587,30 @@
return static_cast<const char_type*>(__builtin_memchr(__s, __a, __n));
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
move(char_type* __s1, const char_type* __s2, size_t __n)
{
if (__n == 0)
return __s1;
- return static_cast<char_type*>(__builtin_memmove(__s1, __s2, __n));
+ return static_cast<char_type*>
+ (std::__detail::__memmove<true>(__s1, __s2, __n));
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
copy(char_type* __s1, const char_type* __s2, size_t __n)
{
if (__n == 0)
return __s1;
- return static_cast<char_type*>(__builtin_memcpy(__s1, __s2, __n));
+ return static_cast<char_type*>(
+ std::__detail::__memcpy(__s1, __s2, __n));
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
assign(char_type* __s, size_t __n, char_type __a)
{
if (__n == 0)
return __s;
- return static_cast<char_type*>(__builtin_memset(__s, __a, __n));
+ return static_cast<char_type*>(std::__detail::__memset(__s, __a, __n));
}
static _GLIBCXX_CONSTEXPR char_type
@@ -680,25 +702,25 @@
return 0;
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
move(char_type* __s1, const char_type* __s2, size_t __n)
{
if (__n == 0)
return __s1;
- return (static_cast<char_type*>
- (__builtin_memmove(__s1, __s2, __n * sizeof(char_type))));
+ return static_cast<char_type*>
+ (std::__detail::__memmove<true>(__s1, __s2, __n));
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
copy(char_type* __s1, const char_type* __s2, size_t __n)
{
if (__n == 0)
return __s1;
- return (static_cast<char_type*>
- (__builtin_memcpy(__s1, __s2, __n * sizeof(char_type))));
+ return static_cast<char_type*>(
+ std::__detail::__memcpy(__s1, __s2, __n));
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
assign(char_type* __s, size_t __n, char_type __a)
{
for (size_t __i = 0; __i < __n; ++__i)
@@ -783,25 +805,25 @@
return 0;
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
move(char_type* __s1, const char_type* __s2, size_t __n)
{
if (__n == 0)
return __s1;
return (static_cast<char_type*>
- (__builtin_memmove(__s1, __s2, __n * sizeof(char_type))));
+ (std::__detail::__memmove<true>(__s1, __s2, __n)));
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
copy(char_type* __s1, const char_type* __s2, size_t __n)
{
if (__n == 0)
return __s1;
- return (static_cast<char_type*>
- (__builtin_memcpy(__s1, __s2, __n * sizeof(char_type))));
+ return (static_cast<char_type*>(
+ std::__detail::__memcpy(__s1, __s2, __n)));
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
assign(char_type* __s, size_t __n, char_type __a)
{
for (size_t __i = 0; __i < __n; ++__i)
Index: include/bits/stl_algobase.h
===================================================================
--- include/bits/stl_algobase.h (revision 279174)
+++ include/bits/stl_algobase.h (working copy)
@@ -80,19 +80,22 @@
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
+namespace __detail
+{
/*
* A constexpr wrapper for __builtin_memmove.
+ * When constant-evaluated performs a forward copy.
* @param __num The number of elements of type _Tp (not bytes).
*/
template<bool _IsMove, typename _Tp>
_GLIBCXX14_CONSTEXPR
inline void*
- __memmove(_Tp* __dst, const _Tp* __src, size_t __num)
+ __memmove(_Tp* __dst, const _Tp* __src, ptrdiff_t __num)
{
#ifdef __cpp_lib_is_constant_evaluated
if (std::is_constant_evaluated())
{
- for(; __num > 0; --__num)
+ for (; __num > 0; --__num)
{
if constexpr (_IsMove)
*__dst = std::move(*__src);
@@ -106,10 +109,81 @@
else
#endif
return __builtin_memmove(__dst, __src, sizeof(_Tp) * __num);
- return __dst;
}
/*
+ * A constexpr wrapper for __builtin_memmove.
+ * When constant-evaluated performs a backward copy.
+ * @param __num The number of elements of type _Tp (not bytes).
+ */
+ template<bool _IsMove, typename _Tp>
+ _GLIBCXX14_CONSTEXPR
+ inline void*
+ __copy_backward(_Tp* __dst, const _Tp* __src, ptrdiff_t __num)
+ {
+#ifdef __cpp_lib_is_constant_evaluated
+ if (std::is_constant_evaluated())
+ {
+ __dst += __num;
+ __src += __num;
+ for (; __num != 0; --__num)
+ {
+ if constexpr (_IsMove)
+ *--__dst = std::move(*--__src);
+ else
+ *--__dst = *--__src;
+ }
+ return __dst;
+ }
+ else
+#endif
+ return __builtin_memmove(__dst, __src, sizeof(_Tp) * __num);
+ }
+
+ /*
+ * A constexpr wrapper for __builtin_memcpy.
+ * When constant-evaluated performs a forward copy.
+ * @param __num The number of elements of type _Tp (not bytes).
+ */
+ template<typename _Tp>
+ _GLIBCXX14_CONSTEXPR
+ inline void*
+ __memcpy(_Tp* __dst, const _Tp* __src, ptrdiff_t __num)
+ {
+#ifdef __cpp_lib_is_constant_evaluated
+ if (std::is_constant_evaluated())
+ {
+ for (; __num > 0; --__num)
+ *__dst++ = *__src++;
+ return __dst;
+ }
+ else
+#endif
+ return __builtin_memcpy(__dst, __src, sizeof(_Tp) * __num);
+ }
+
+ /*
+ * A constexpr wrapper for __builtin_memset.
+ * @param __num The number of elements of type _Tp (not bytes).
+ */
+ template<typename _Tp>
+ _GLIBCXX14_CONSTEXPR
+ inline void*
+ __memset(_Tp* __dst, _Tp __a, ptrdiff_t __num)
+ {
+#ifdef __cpp_lib_is_constant_evaluated
+ if (std::is_constant_evaluated())
+ {
+ for (; __num > 0; --__num)
+ *__dst = __a;
+ return __dst;
+ }
+ else
+#endif
+ return __builtin_memset(__dst, __a, sizeof(_Tp) * __num);
+ }
+
+ /*
* A constexpr wrapper for __builtin_memcmp.
* @param __num The number of elements of type _Tp (not bytes).
*/
@@ -116,12 +190,12 @@
template<typename _Tp>
_GLIBCXX14_CONSTEXPR
inline int
- __memcmp(const _Tp* __first1, const _Tp* __first2, size_t __num)
+ __memcmp(const _Tp* __first1, const _Tp* __first2, ptrdiff_t __num)
{
#ifdef __cpp_lib_is_constant_evaluated
if (std::is_constant_evaluated())
{
- for(; __num > 0; ++__first1, ++__first2, --__num)
+ for (; __num > 0; ++__first1, ++__first2, --__num)
if (*__first1 != *__first2)
return *__first1 < *__first2 ? -1 : 1;
return 0;
@@ -130,6 +204,7 @@
#endif
return __builtin_memcmp(__first1, __first2, sizeof(_Tp) * __num);
}
+} // namespace __detail
#if __cplusplus < 201103L
// See http://gcc.gnu.org/ml/libstdc++/2004-08/msg00167.html: in a
@@ -449,7 +524,7 @@
#endif
const ptrdiff_t _Num = __last - __first;
if (_Num)
- std::__memmove<_IsMove>(__result, __first, _Num);
+ std::__detail::__memmove<_IsMove>(__result, __first, _Num);
return __result + _Num;
}
};
@@ -661,7 +736,7 @@
#endif
const ptrdiff_t _Num = __last - __first;
if (_Num)
- std::__memmove<_IsMove>(__result - _Num, __first, _Num);
+ std::__detail::__memmove<_IsMove>(__result - _Num, __first, _Num);
return __result - _Num;
}
};
@@ -983,7 +1058,7 @@
equal(const _Tp* __first1, const _Tp* __last1, const _Tp* __first2)
{
if (const size_t __len = (__last1 - __first1))
- return !std::__memcmp(__first1, __first2, __len);
+ return !std::__detail::__memcmp(__first1, __first2, __len);
return true;
}
};
@@ -1097,7 +1172,8 @@
const size_t __len1 = __last1 - __first1;
const size_t __len2 = __last2 - __first2;
if (const size_t __len = std::min(__len1, __len2))
- if (int __result = std::__memcmp(__first1, __first2, __len))
+ if (int __result = std::__detail::__memcmp(__first1, __first2,
+ __len))
return __result < 0;
return __len1 < __len2;
}
Index: include/ext/pod_char_traits.h
===================================================================
--- include/ext/pod_char_traits.h (revision 279174)
+++ include/ext/pod_char_traits.h (working copy)
@@ -56,7 +56,7 @@
value_type value;
template<typename V2>
- static char_type
+ static _GLIBCXX_CONSTEXPR char_type
from(const V2& v)
{
char_type ret = { static_cast<value_type>(v) };
@@ -64,7 +64,7 @@
}
template<typename V2>
- static V2
+ static _GLIBCXX_CONSTEXPR V2
to(const char_type& c)
{
V2 ret = { static_cast<V2>(c.value) };
@@ -74,13 +74,13 @@
};
template<typename _Value, typename _Int, typename _St>
- inline bool
+ inline _GLIBCXX_CONSTEXPR bool
operator==(const character<_Value, _Int, _St>& lhs,
const character<_Value, _Int, _St>& rhs)
{ return lhs.value == rhs.value; }
template<typename _Value, typename _Int, typename _St>
- inline bool
+ inline _GLIBCXX_CONSTEXPR bool
operator<(const character<_Value, _Int, _St>& lhs,
const character<_Value, _Int, _St>& rhs)
{ return lhs.value < rhs.value; }
@@ -102,19 +102,19 @@
typedef fpos<state_type> pos_type;
typedef streamoff off_type;
- static void
+ static _GLIBCXX14_CONSTEXPR void
assign(char_type& __c1, const char_type& __c2)
{ __c1 = __c2; }
- static bool
+ static _GLIBCXX_CONSTEXPR bool
eq(const char_type& __c1, const char_type& __c2)
{ return __c1 == __c2; }
- static bool
+ static _GLIBCXX_CONSTEXPR bool
lt(const char_type& __c1, const char_type& __c2)
{ return __c1 < __c2; }
- static int
+ static _GLIBCXX14_CONSTEXPR int
compare(const char_type* __s1, const char_type* __s2, size_t __n)
{
for (size_t __i = 0; __i < __n; ++__i)
@@ -123,7 +123,7 @@
return 0;
}
- static size_t
+ static _GLIBCXX14_CONSTEXPR size_t
length(const char_type* __s)
{
const char_type* __p = __s;
@@ -132,7 +132,7 @@
return (__p - __s);
}
- static const char_type*
+ static _GLIBCXX14_CONSTEXPR const char_type*
find(const char_type* __s, size_t __n, const char_type& __a)
{
for (const char_type* __p = __s; size_t(__p - __s) < __n; ++__p)
@@ -141,7 +141,7 @@
return 0;
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
move(char_type* __s1, const char_type* __s2, size_t __n)
{
if (__n == 0)
@@ -150,7 +150,7 @@
(__builtin_memmove(__s1, __s2, __n * sizeof(char_type)));
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
copy(char_type* __s1, const char_type* __s2, size_t __n)
{
if (__n == 0)
@@ -159,7 +159,7 @@
return __s1;
}
- static char_type*
+ static _GLIBCXX20_CONSTEXPR char_type*
assign(char_type* __s, size_t __n, char_type __a)
{
std::fill_n(__s, __n, __a);
@@ -166,19 +166,19 @@
return __s;
}
- static char_type
+ static _GLIBCXX_CONSTEXPR char_type
to_char_type(const int_type& __i)
{ return char_type::template from(__i); }
- static int_type
+ static _GLIBCXX_CONSTEXPR int_type
to_int_type(const char_type& __c)
{ return char_type::template to<int_type>(__c); }
- static bool
+ static _GLIBCXX_CONSTEXPR bool
eq_int_type(const int_type& __c1, const int_type& __c2)
{ return __c1 == __c2; }
- static int_type
+ static _GLIBCXX_CONSTEXPR int_type
eof()
{
int_type __r = { static_cast<typename __gnu_cxx::__conditional_type
@@ -187,7 +187,7 @@
return __r;
}
- static int_type
+ static _GLIBCXX_CONSTEXPR int_type
not_eof(const int_type& __c)
{ return eq_int_type(__c, eof()) ? int_type() : __c; }
};
Index: include/std/string_view
===================================================================
--- include/std/string_view (revision 279174)
+++ include/std/string_view (working copy)
@@ -262,6 +262,7 @@
// [string.view.ops], string operations:
+ _GLIBCXX20_CONSTEXPR
size_type
copy(_CharT* __str, size_type __n, size_type __pos = 0) const
{
Index: testsuite/21_strings/char_traits/requirements/char/constexpr.cc
===================================================================
--- testsuite/21_strings/char_traits/requirements/char/constexpr.cc (nonexistent)
+++ testsuite/21_strings/char_traits/requirements/char/constexpr.cc (working copy)
@@ -0,0 +1,42 @@
+// { dg-options "-std=gnu++2a" }
+// { dg-do compile { target c++2a } }
+//
+// Copyright (C) 2019 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library 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, or (at your option)
+// any later version.
+
+// This library 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 library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <string>
+
+constexpr bool
+test()
+{
+ auto ok = true;
+
+ char casv[8]{"ello, W"};
+
+ char das[8]{};
+ std::char_traits<char>::move(das, casv, 7);
+ std::char_traits<char>::copy(das, casv, 7);
+ std::char_traits<char>::assign(das, 7, 'x');
+
+ return ok;
+}
+
+int
+main()
+{
+ static_assert(test());
+}
Index: testsuite/21_strings/char_traits/requirements/wchar_t/constexpr.cc
===================================================================
--- testsuite/21_strings/char_traits/requirements/wchar_t/constexpr.cc (nonexistent)
+++ testsuite/21_strings/char_traits/requirements/wchar_t/constexpr.cc (working copy)
@@ -0,0 +1,42 @@
+// { dg-options "-std=gnu++2a" }
+// { dg-do compile { target c++2a } }
+//
+// Copyright (C) 2019 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library 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, or (at your option)
+// any later version.
+
+// This library 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 library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <string>
+
+constexpr bool
+test()
+{
+ auto ok = true;
+
+ wchar_t cawsv[8]{L"ello, W"};
+
+ wchar_t wdas[8]{};
+ std::char_traits<wchar_t>::move(wdas, cawsv, 7);
+ std::char_traits<wchar_t>::copy(wdas, cawsv, 7);
+ std::char_traits<wchar_t>::assign(wdas, 7, L'x');
+
+ return ok;
+}
+
+int
+main()
+{
+ static_assert(test());
+}
Index: testsuite/21_strings/basic_string_view/operations/copy/char/constexpr.cc
===================================================================
--- testsuite/21_strings/basic_string_view/operations/copy/char/constexpr.cc (nonexistent)
+++ testsuite/21_strings/basic_string_view/operations/copy/char/constexpr.cc (working copy)
@@ -0,0 +1,37 @@
+// { dg-options "-std=gnu++2a" }
+// { dg-do compile { target c++2a } }
+//
+// Copyright (C) 2019 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library 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, or (at your option)
+// any later version.
+//
+// This library 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 library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <string_view>
+
+constexpr bool
+test_string_view()
+{
+ auto ok = true;
+
+ constexpr std::string_view sv = "Hello, World!!!";
+ char casv[8]{};
+ sv.copy(casv, 7, 1);
+
+ ok = ok && (casv[0] == 'e');
+
+ return ok;
+}
+
+static_assert(test_string_view());
Index: testsuite/21_strings/basic_string_view/operations/copy/wchar_t/constexpr.cc
===================================================================
--- testsuite/21_strings/basic_string_view/operations/copy/wchar_t/constexpr.cc (nonexistent)
+++ testsuite/21_strings/basic_string_view/operations/copy/wchar_t/constexpr.cc (working copy)
@@ -0,0 +1,37 @@
+// { dg-options "-std=gnu++2a" }
+// { dg-do compile { target c++2a } }
+//
+// Copyright (C) 2019 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library 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, or (at your option)
+// any later version.
+//
+// This library 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 library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <string_view>
+
+constexpr bool
+test_string_view()
+{
+ auto ok = true;
+
+ constexpr std::wstring_view wsv = L"Hello, World!!!";
+ wchar_t cawsv[8]{};
+ wsv.copy(cawsv, 7, 1);
+
+ ok = ok && (cawsv[0] == L'e');
+
+ return ok;
+}
+
+static_assert(test_string_view());
2019-12-10 Edward Smith-Rowland <[email protected]>
Implement the <iterator> part of C++20 p1032 Misc constexpr bits.
* include/bits/stl_iterator.h (back_insert_iterator, back_inserter)
(front_insert_iterator, front_inserter, insert_iterator, inserter):
Make constexpr.
* testsuite/24_iterators/insert_iterator/requirements/constexpr.cc: New.
* testsuite/24_iterators/back_insert_iterator/requirements/
constexpr.cc: New.
* testsuite/24_iterators/front_insert_iterator/requirements/
constexpr.cc: New.
* testsuite/24_iterators/headers/iterator/synopsis_c++17.cc: Make test
C++17 only and block insert_iterator tests for C++17 (because of include
of synopsis_c++20.cc.
* testsuite/24_iterators/headers/iterator/synopsis_c++20.cc: Add
constexpr inserter tests.
Index: include/bits/stl_iterator.h
===================================================================
--- include/bits/stl_iterator.h (revision 279174)
+++ include/bits/stl_iterator.h (working copy)
@@ -502,8 +502,12 @@
/// A nested typedef for the type of whatever container you used.
typedef _Container container_type;
+#if __cplusplus > 201703L
+ constexpr back_insert_iterator() noexcept = default;
+#endif
+
/// The only way to create this %iterator is with a container.
- explicit
+ explicit _GLIBCXX20_CONSTEXPR
back_insert_iterator(_Container& __x)
: container(std::__addressof(__x)) { }
@@ -526,7 +530,7 @@
return *this;
}
#else
- back_insert_iterator&
+ _GLIBCXX20_CONSTEXPR back_insert_iterator&
operator=(const typename _Container::value_type& __value)
{
container->push_back(__value);
@@ -533,7 +537,7 @@
return *this;
}
- back_insert_iterator&
+ _GLIBCXX20_CONSTEXPR back_insert_iterator&
operator=(typename _Container::value_type&& __value)
{
container->push_back(std::move(__value));
@@ -542,17 +546,17 @@
#endif
/// Simply returns *this.
- back_insert_iterator&
+ _GLIBCXX20_CONSTEXPR back_insert_iterator&
operator*()
{ return *this; }
/// Simply returns *this. (This %iterator does not @a move.)
- back_insert_iterator&
+ _GLIBCXX20_CONSTEXPR back_insert_iterator&
operator++()
{ return *this; }
/// Simply returns *this. (This %iterator does not @a move.)
- back_insert_iterator
+ _GLIBCXX20_CONSTEXPR back_insert_iterator
operator++(int)
{ return *this; }
};
@@ -569,7 +573,7 @@
* types for you.
*/
template<typename _Container>
- inline back_insert_iterator<_Container>
+ inline _GLIBCXX20_CONSTEXPR back_insert_iterator<_Container>
back_inserter(_Container& __x)
{ return back_insert_iterator<_Container>(__x); }
@@ -594,8 +598,13 @@
/// A nested typedef for the type of whatever container you used.
typedef _Container container_type;
+#if __cplusplus > 201703L
+ constexpr front_insert_iterator() noexcept = default;
+#endif
+
/// The only way to create this %iterator is with a container.
- explicit front_insert_iterator(_Container& __x)
+ explicit _GLIBCXX20_CONSTEXPR
+ front_insert_iterator(_Container& __x)
: container(std::__addressof(__x)) { }
/**
@@ -617,14 +626,13 @@
return *this;
}
#else
- front_insert_iterator&
+ _GLIBCXX20_CONSTEXPR front_insert_iterator&
operator=(const typename _Container::value_type& __value)
{
container->push_front(__value);
return *this;
}
-
- front_insert_iterator&
+ _GLIBCXX20_CONSTEXPR front_insert_iterator&
operator=(typename _Container::value_type&& __value)
{
container->push_front(std::move(__value));
@@ -633,17 +641,17 @@
#endif
/// Simply returns *this.
- front_insert_iterator&
+ _GLIBCXX20_CONSTEXPR front_insert_iterator&
operator*()
{ return *this; }
/// Simply returns *this. (This %iterator does not @a move.)
- front_insert_iterator&
+ _GLIBCXX20_CONSTEXPR front_insert_iterator&
operator++()
{ return *this; }
/// Simply returns *this. (This %iterator does not @a move.)
- front_insert_iterator
+ _GLIBCXX20_CONSTEXPR front_insert_iterator
operator++(int)
{ return *this; }
};
@@ -660,7 +668,7 @@
* types for you.
*/
template<typename _Container>
- inline front_insert_iterator<_Container>
+ inline _GLIBCXX20_CONSTEXPR front_insert_iterator<_Container>
front_inserter(_Container& __x)
{ return front_insert_iterator<_Container>(__x); }
@@ -690,10 +698,15 @@
/// A nested typedef for the type of whatever container you used.
typedef _Container container_type;
+#if __cplusplus > 201703L
+ constexpr insert_iterator() = default;
+#endif
+
/**
* The only way to create this %iterator is with a container and an
* initial position (a normal %iterator into the container).
*/
+ _GLIBCXX20_CONSTEXPR
insert_iterator(_Container& __x, typename _Container::iterator __i)
: container(std::__addressof(__x)), iter(__i) {}
@@ -729,7 +742,7 @@
return *this;
}
#else
- insert_iterator&
+ _GLIBCXX20_CONSTEXPR insert_iterator&
operator=(const typename _Container::value_type& __value)
{
iter = container->insert(iter, __value);
@@ -737,7 +750,7 @@
return *this;
}
- insert_iterator&
+ _GLIBCXX20_CONSTEXPR insert_iterator&
operator=(typename _Container::value_type&& __value)
{
iter = container->insert(iter, std::move(__value));
@@ -747,17 +760,17 @@
#endif
/// Simply returns *this.
- insert_iterator&
+ _GLIBCXX20_CONSTEXPR insert_iterator&
operator*()
{ return *this; }
/// Simply returns *this. (This %iterator does not @a move.)
- insert_iterator&
+ _GLIBCXX20_CONSTEXPR insert_iterator&
operator++()
{ return *this; }
/// Simply returns *this. (This %iterator does not @a move.)
- insert_iterator&
+ _GLIBCXX20_CONSTEXPR insert_iterator&
operator++(int)
{ return *this; }
};
@@ -775,7 +788,7 @@
* types for you.
*/
template<typename _Container, typename _Iterator>
- inline insert_iterator<_Container>
+ inline _GLIBCXX20_CONSTEXPR insert_iterator<_Container>
inserter(_Container& __x, _Iterator __i)
{
return insert_iterator<_Container>(__x,
Index: testsuite/24_iterators/back_insert_iterator/requirements/constexpr.cc
===================================================================
--- testsuite/24_iterators/back_insert_iterator/requirements/constexpr.cc (nonexistent)
+++ testsuite/24_iterators/back_insert_iterator/requirements/constexpr.cc (working copy)
@@ -0,0 +1,67 @@
+// { dg-options "-std=gnu++2a" }
+// { dg-do compile { target c++2a } }
+//
+// Copyright (C) 2019 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library 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, or (at your option)
+// any later version.
+//
+// This library 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 library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <iterator>
+#include <array>
+
+template<typename Tp>
+ struct listoid
+ {
+ using value_type = Tp;
+ using iterator = size_t;
+
+ constexpr listoid() = default;
+
+ constexpr void push_back(const value_type& value) { return; }
+ constexpr void push_back(value_type&& value) { return; }
+ constexpr void push_front(const value_type& value) { return; }
+ constexpr void push_front(value_type&& value) { return; }
+ constexpr iterator insert(iterator pos, const value_type& value) { return pos; }
+ constexpr iterator begin() noexcept { return _M_begin; }
+ constexpr iterator end() noexcept { return _M_end; }
+
+ private:
+ size_t _M_begin = 0;
+ size_t _M_end = 0;
+ };
+
+constexpr bool
+test()
+{
+ listoid<int> l;
+
+ auto ok = true;
+ const int route = 66;
+
+ constexpr std::array<int, 2> b{89, 99};
+ const std::back_insert_iterator<listoid<int>> bi(l);
+ std::copy(b.begin(), b.end(), bi);
+ auto nbi = std::back_inserter(l);
+ nbi = route;
+ nbi = 77;
+
+ return ok;
+}
+
+int
+main()
+{
+ static_assert(test());
+}
Index: testsuite/24_iterators/insert_iterator/requirements/constexpr.cc
===================================================================
--- testsuite/24_iterators/insert_iterator/requirements/constexpr.cc (nonexistent)
+++ testsuite/24_iterators/insert_iterator/requirements/constexpr.cc (working copy)
@@ -0,0 +1,68 @@
+// { dg-options "-std=gnu++2a" }
+// { dg-do compile { target c++2a } }
+//
+// Copyright (C) 2019 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library 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, or (at your option)
+// any later version.
+//
+// This library 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 library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <iterator>
+#include <array>
+
+template<typename Tp>
+ struct listoid
+ {
+ using value_type = Tp;
+ using iterator = size_t;
+
+ constexpr listoid() = default;
+
+ constexpr void push_back(const value_type& value) { return; }
+ constexpr void push_back(value_type&& value) { return; }
+ constexpr void push_front(const value_type& value) { return; }
+ constexpr void push_front(value_type&& value) { return; }
+ constexpr iterator insert(iterator pos, const value_type& value) { return pos; }
+ constexpr iterator begin() noexcept { return _M_begin; }
+ constexpr iterator end() noexcept { return _M_end; }
+
+ private:
+ size_t _M_begin = 0;
+ size_t _M_end = 0;
+ };
+
+constexpr bool
+test()
+{
+ listoid<int> l;
+
+ auto ok = true;
+ const int route = 66;
+
+ constexpr std::array<int, 5> a{1, 2, 3, 4, 5};
+ const auto liter = l.begin() + 1;
+ const std::insert_iterator<listoid<int>> ii(l, liter);
+ std::copy(a.begin(), a.end(), ii);
+ auto nii = std::inserter(l, liter);
+ nii = route;
+ nii = 77;
+
+ return ok;
+}
+
+int
+main()
+{
+ static_assert(test());
+}
Index: testsuite/24_iterators/front_insert_iterator/requirements/constexpr.cc
===================================================================
--- testsuite/24_iterators/front_insert_iterator/requirements/constexpr.cc (nonexistent)
+++ testsuite/24_iterators/front_insert_iterator/requirements/constexpr.cc (working copy)
@@ -0,0 +1,67 @@
+// { dg-options "-std=gnu++2a" }
+// { dg-do compile { target c++2a } }
+//
+// Copyright (C) 2019 Free Software Foundation, Inc.
+//
+// This file is part of the GNU ISO C++ Library. This library 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, or (at your option)
+// any later version.
+//
+// This library 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 library; see the file COPYING3. If not see
+// <http://www.gnu.org/licenses/>.
+
+#include <iterator>
+#include <array>
+
+template<typename Tp>
+ struct listoid
+ {
+ using value_type = Tp;
+ using iterator = size_t;
+
+ constexpr listoid() = default;
+
+ constexpr void push_back(const value_type& value) { return; }
+ constexpr void push_back(value_type&& value) { return; }
+ constexpr void push_front(const value_type& value) { return; }
+ constexpr void push_front(value_type&& value) { return; }
+ constexpr iterator insert(iterator pos, const value_type& value) { return pos; }
+ constexpr iterator begin() noexcept { return _M_begin; }
+ constexpr iterator end() noexcept { return _M_end; }
+
+ private:
+ size_t _M_begin = 0;
+ size_t _M_end = 0;
+ };
+
+constexpr bool
+test()
+{
+ listoid<int> l;
+
+ auto ok = true;
+ const int route = 66;
+
+ constexpr std::array<int, 2> f{-1, 0};
+ const std::front_insert_iterator<listoid<int>> fi(l);
+ std::copy(f.begin(), f.end(), fi);
+ auto nfi = std::front_inserter(l);
+ nfi = route;
+ nfi = 77;
+
+ return ok;
+}
+
+int
+main()
+{
+ static_assert(test());
+}
Index: testsuite/24_iterators/headers/iterator/synopsis_c++17.cc
===================================================================
--- testsuite/24_iterators/headers/iterator/synopsis_c++17.cc (revision 279174)
+++ testsuite/24_iterators/headers/iterator/synopsis_c++17.cc (working copy)
@@ -1,5 +1,5 @@
// { dg-options "-std=gnu++17" }
-// { dg-do compile }
+// { dg-do compile { target c++17_only } }
// { dg-require-normal-namespace "" }
// Copyright (C) 2016-2019 Free Software Foundation, Inc.
@@ -88,7 +88,7 @@
template <class Iterator>
constexpr reverse_iterator<Iterator> make_reverse_iterator(const Iterator&);
-
+#if __cplusplus == 201703L
template <class Container> class back_insert_iterator;
template <class Container>
@@ -103,7 +103,7 @@
template <class Container, class Iterator>
insert_iterator<Container> inserter(Container& x, Iterator i);
-
+#endif
template <class Iterator> class move_iterator;
template <class Iterator1, class Iterator2>
Index: testsuite/24_iterators/headers/iterator/synopsis_c++20.cc
===================================================================
--- testsuite/24_iterators/headers/iterator/synopsis_c++20.cc (revision 279174)
+++ testsuite/24_iterators/headers/iterator/synopsis_c++20.cc (working copy)
@@ -76,6 +76,21 @@
struct iterator_traits<counted_iterator<I>>;
struct unreachable_sentinel_t;
+
+ template <class Container> class back_insert_iterator;
+
+ template <class Container>
+ constexpr back_insert_iterator<Container> back_inserter(Container& x);
+
+ template <class Container> class front_insert_iterator;
+
+ template <class Container>
+ constexpr front_insert_iterator<Container> front_inserter(Container& x);
+
+ template <class Container> class insert_iterator;
+
+ template <class Container, class Iterator>
+ constexpr insert_iterator<Container> inserter(Container& x, Iterator i);
}
struct I { };
