Viewing file:  atomicity.h (2.76 KB) -rw-r--r--
Select action/file-type:
 (+) |  (+) |  (+) | Code (+) | Session (+) |  (+) | SDB (+) |  (+) |  (+) |  (+) |  (+) |  (+) |
// Low-level functions for atomic operations: PA-RISC version -*- C++ -*-
// Copyright (C) 2002-2022 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.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
#include <bits/c++config.h>
#include <ext/atomicity.h>
namespace __gnu_cxx _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
template<int _Inst>
struct _Atomicity_lock
{
static volatile int _S_atomicity_lock;
};
template<int _Inst>
volatile int
_Atomicity_lock<_Inst>::_S_atomicity_lock __attribute__ ((aligned (16))) = 1;
// Because of the lack of weak support when using the hpux som
// linker, we explicitly instantiate the atomicity lock.
template volatile int _Atomicity_lock<0>::_S_atomicity_lock;
int
__attribute__ ((__unused__))
__exchange_and_add(volatile _Atomic_word* __mem, int __val) throw ()
{
_Atomic_word result;
int tmp;
volatile int& lock = _Atomicity_lock<0>::_S_atomicity_lock;
__asm__ __volatile__ ("ldcw 0(%1),%0\n\t"
"cmpib,<>,n 0,%0,.+20\n\t"
"ldw 0(%1),%0\n\t"
"cmpib,= 0,%0,.-4\n\t"
"nop\n\t"
"b,n .-20"
: "=&r" (tmp)
: "r" (&lock)
: "memory");
result = *__mem;
*__mem = result + __val;
__asm__ __volatile__ ("stw %1,0(%0)"
: : "r" (&lock), "r" (tmp) : "memory");
return result;
}
void
__attribute__ ((__unused__))
__atomic_add(volatile _Atomic_word* __mem, int __val) throw ()
{
int tmp;
volatile int& lock = _Atomicity_lock<0>::_S_atomicity_lock;
__asm__ __volatile__ ("ldcw 0(%1),%0\n\t"
"cmpib,<>,n 0,%0,.+20\n\t"
"ldw 0(%1),%0\n\t"
"cmpib,= 0,%0,.-4\n\t"
"nop\n\t"
"b,n .-20"
: "=&r" (tmp)
: "r" (&lock)
: "memory");
*__mem += __val;
__asm__ __volatile__ ("stw %1,0(%0)"
: : "r" (&lock), "r" (tmp) : "memory");
}
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
|
