libstdc++-v3/testsuite/29_atomics/atomic/operators/pointer_partial_void.cc

   1 // { dg-require-atomic-builtins "" }
   2 // { dg-options "-std=gnu++0x" }
   3
   4 // Copyright (C) 2012-2013 Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 3, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING3.  If not see
  19 // <http://www.gnu.org/licenses/>.
  20
  21 #include <atomic>
  22 #include <cstdlib> //std::abs
  23 #include <testsuite_hooks.h>
  24
  25 // pointer arithimetic vs. atomic<void*>.
  26 // atomic<void*> vs. explicitly specialized w/o operators, like atomic_bool?
  27 int main(void)
  28 {
  29   using namespace std;
  30
  31   typedef int   value_type;
  32   const size_t n = 2;
  33   value_type value = 42;
  34   value_type* p = &value;
  35   void* vp = p;
  36   ptrdiff_t __attribute__((unused)) dist(0);
  37
  38   atomic<void*> a(vp);
  39
  40   // operator++
  41   void* vp2(a);
  42   a++;
  43   void* vp3(a);
  44   dist = reinterpret_cast<char*>(vp2) - reinterpret_cast<char*>(vp3);
  45   // VERIFY ( std::abs(dist) == sizeof(void*));
  46
  47   // operator--
  48   void* vp4(a);
  49   a--;
  50   void* vp5(a);
  51   dist = reinterpret_cast<char*>(vp4) - reinterpret_cast<char*>(vp5);
  52   // VERIFY ( std::abs(dist) == sizeof(void*));
  53
  54   // operator+=
  55   void* vp6(a);
  56   a+=n;
  57   void* vp7(a);
  58   dist = reinterpret_cast<char*>(vp6) - reinterpret_cast<char*>(vp7);
  59   // VERIFY ( std::abs(dist) == sizeof(void*) * n);
  60
  61   // operator-=
  62   void* vp8(a);
  63   a-=n;
  64   void* vp9(a);
  65   dist = reinterpret_cast<char*>(vp8) - reinterpret_cast<char*>(vp9);
  66   //VERIFY ( std::abs(dist) == sizeof(void*) * n);
  67
  68   return 0;
  69 }