diff libstdc++-v3/testsuite/26_numerics/bit/bit.pow.two/bit_ceil_neg.cc @ 19:2b5abeee2509 default tip

update gcc11
author anatofuz
date Mon, 25 May 2020 07:50:57 +0900
parents
children
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libstdc++-v3/testsuite/26_numerics/bit/bit.pow.two/bit_ceil_neg.cc	Mon May 25 07:50:57 2020 +0900
@@ -0,0 +1,75 @@
+// Copyright (C) 2019-2020 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/>.
+
+// { dg-options "-std=gnu++2a -D_GLIBCXX_ASSERTIONS" }
+// { dg-do run { target c++2a } }
+// { dg-xfail-run-if "__glibcxx_assert in bit_ceil should fail" { *-*-* } }
+
+#include <bit>
+#include <limits>
+
+// P1355R2: not a constant expression if the result is not representable
+
+template<auto N, typename = void>
+  struct bit_ceil_valid
+  : std::false_type { };
+
+template<auto N>
+  struct bit_ceil_valid<N, std::void_t<char[(std::bit_ceil(N), 1)]>>
+  : std::true_type { };
+
+template<typename T>
+  constexpr T max = std::numeric_limits<T>::max();
+template<typename T>
+  constexpr T maxpow2 = T(1) << (std::numeric_limits<T>::digits - 1);
+
+static_assert( bit_ceil_valid<maxpow2<unsigned char>>() );
+static_assert( !bit_ceil_valid<maxpow2<unsigned char> + (unsigned char)1>() );
+
+static_assert( !bit_ceil_valid<max<unsigned char>>() );
+static_assert( !bit_ceil_valid<max<unsigned char> - (unsigned char)1>() );
+
+static_assert( bit_ceil_valid<maxpow2<unsigned short>>() );
+static_assert( !bit_ceil_valid<maxpow2<unsigned short> + (unsigned short)1>() );
+static_assert( !bit_ceil_valid<max<unsigned short>>() );
+static_assert( !bit_ceil_valid<max<unsigned short> - (unsigned short)1>() );
+
+static_assert( bit_ceil_valid<maxpow2<unsigned int>>() );
+static_assert( !bit_ceil_valid<maxpow2<unsigned int> + 1u>() );
+static_assert( !bit_ceil_valid<max<unsigned int>>() );
+static_assert( !bit_ceil_valid<max<unsigned int> - 1u>() );
+
+static_assert( bit_ceil_valid<maxpow2<unsigned long>>() );
+static_assert( !bit_ceil_valid<maxpow2<unsigned long> + 1ul>() );
+static_assert( !bit_ceil_valid<max<unsigned long>>() );
+static_assert( !bit_ceil_valid<max<unsigned long> - 1ul>() );
+
+static_assert( bit_ceil_valid<maxpow2<unsigned long long>>() );
+static_assert( !bit_ceil_valid<maxpow2<unsigned long long> + 1ull>() );
+static_assert( !bit_ceil_valid<max<unsigned long long>>() );
+static_assert( !bit_ceil_valid<max<unsigned long long> - 1ull>() );
+
+void
+test01()
+{
+  std::bit_ceil( maxpow2<unsigned> + 1u ); // should fail __glibcxx_assert
+}
+
+int main()
+{
+  test01();
+}