libstdc++-v3/testsuite/18_support/new_aligned.cc

   1 // Copyright (C) 2018-2024 Free Software Foundation, Inc.
   2 //
   3 // This file is part of the GNU ISO C++ Library.  This library is free
   4 // software; you can redistribute it and/or modify it under the
   5 // terms of the GNU General Public License as published by the
   6 // Free Software Foundation; either version 3, or (at your option)
   7 // any later version.
   8
   9 // This library is distributed in the hope that it will be useful,
  10 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 // GNU General Public License for more details.
  13
  14 // You should have received a copy of the GNU General Public License along
  15 // with this library; see the file COPYING3.  If not see
  16 // <http://www.gnu.org/licenses/>.
  17
  18 // { dg-do run { target c++17 } }
  19
  20 #include <new>
  21 #include <memory>
  22 #include <testsuite_hooks.h>
  23
  24 struct Test
  25 {
  26   Test(std::size_t size, std::size_t a)
  27   : size(size), alignment(std::align_val_t{a}),
  28     p(::operator new(size, alignment))
  29   { }
  30
  31   ~Test() { ::operator delete(p, size, alignment); }
  32
  33   std::size_t size;
  34   std::align_val_t alignment;
  35   void* p;
  36
  37   bool valid() const { return p != nullptr; }
  38
  39   bool aligned() const
  40   {
  41     auto ptr = p;
  42     auto space = size;
  43     return std::align((std::size_t)alignment, size, ptr, space) == p;
  44   }
  45 };
  46
  47 // operator new(size_t size, align_val_t alignment) has
  48 // undefined behaviour if the alignment argument is not
  49 // a valid alignment value (i.e. not a power of two).
  50 //
  51 // Unlike posix_memalign there is no requirement that
  52 // alignment >= sizeof(void*).
  53 //
  54 // Unlike aligned_alloc there is no requirement that
  55 // size is an integer multiple of alignment.
  56
  57 void
  58 test01()
  59 {
  60   // Test small values that would not be valid for
  61   // posix_memalign or aligned_alloc.
  62
  63   Test t11{1, 1};
  64   VERIFY( t11.valid() );
  65   VERIFY( t11.aligned() );
  66
  67   Test t21{2, 1};
  68   VERIFY( t21.valid() );
  69   VERIFY( t21.aligned() );
  70
  71   Test t12{1, 2};
  72   VERIFY( t12.valid() );
  73   VERIFY( t12.aligned() );
  74
  75   Test t22{2, 2};
  76   VERIFY( t22.valid() );
  77   VERIFY( t22.aligned() );
  78
  79   Test t32{3, 2};
  80   VERIFY( t32.valid() );
  81   VERIFY( t32.aligned() );
  82
  83   Test t42{4, 2};
  84   VERIFY( t42.valid() );
  85   VERIFY( t42.aligned() );
  86
  87   Test t24{2, 4};
  88   VERIFY( t24.valid() );
  89   VERIFY( t24.aligned() );
  90
  91   Test t34{3, 4};
  92   VERIFY( t34.valid() );
  93   VERIFY( t34.aligned() );
  94
  95   Test t44{4, 4};
  96   VERIFY( t44.valid() );
  97   VERIFY( t44.aligned() );
  98
  99   // Test some larger values.
 100
 101   Test t128_16{128, 16};
 102   VERIFY( t128_16.valid() );
 103   VERIFY( t128_16.aligned() );
 104
 105   Test t128_64{128, 64};
 106   VERIFY( t128_64.valid() );
 107   VERIFY( t128_64.aligned() );
 108
 109   Test t64_128{64, 128};
 110   VERIFY( t64_128.valid() );
 111   VERIFY( t64_128.aligned() );
 112 }
 113
 114 int
 115 main()
 116 {
 117   test01();
 118 }