libstdc++-v3/testsuite/20_util/align/1.cc

   1 // { dg-do run { target c++11 } }
   2
   3 // 2014-04-16 Rüdiger Sonderfeld  <ruediger@c-plusplus.de>
   4
   5 // Copyright (C) 2014-2021 Free Software Foundation, Inc.
   6 //
   7 // This file is part of the GNU ISO C++ Library.  This library is free
   8 // software; you can redistribute it and/or modify it under the terms
   9 // of the GNU General Public License as published by the Free Software
  10 // Foundation; either version 3, or (at your option) any later
  11 // version.
  12
  13 // This library is distributed in the hope that it will be useful, but
  14 // WITHOUT ANY WARRANTY; without even the implied warranty of
  15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16 // General Public License for more details.
  17
  18 // You should have received a copy of the GNU General Public License
  19 // along with this library; see the file COPYING3.  If not see
  20 // <http://www.gnu.org/licenses/>.
  21
  22 // C++11 [ptr.align] (20.6.5): std::align
  23
  24 // { dg-require-cstdint "" }
  25
  26 #include <memory>
  27 #include <cstdint>
  28 #include <testsuite_hooks.h>
  29
  30 void
  31 test01()
  32 {
  33   using std::size_t;
  34
  35   size_t space = 100;
  36   void* ptr = new char[space];
  37   char* const orig_ptr = static_cast<char*>(ptr);
  38   char* old_ptr = orig_ptr;
  39   const size_t orig_space = space;
  40   size_t old_space = space;
  41   const size_t alignment = 16;
  42   const size_t size = 10;
  43   while( void* const r = std::align(alignment, size, ptr, space) )
  44     {
  45       VERIFY( r == ptr );
  46       uintptr_t p = reinterpret_cast<uintptr_t>(ptr);
  47       VERIFY( p % alignment == 0 );
  48       char* const x = static_cast<char*>(ptr);
  49       VERIFY( size_t(x - old_ptr) == old_space - space );
  50       VERIFY( (void*)x < (void*)(orig_ptr + orig_space) );
  51       VERIFY( (void*)(x + size) < (void*)(orig_ptr + orig_space) );
  52       ptr = x + size;
  53       old_ptr = x;
  54       old_space = space;
  55       space -= size;
  56     }
  57   delete [] orig_ptr;
  58 }
  59
  60 int main()
  61 {
  62   test01();
  63 }