gcc/libstdc++-v3/config/cpu/hppa/atomicity.h
John David Anglin 8f0d85d6e8 atomicity.h (__exchange_and_add): Don't use ordered store.
* config/cpu/hppa/atomicity.h (__exchange_and_add): Don't use ordered
	store.
	(__atomic_add): Likewise.

From-SVN: r120751
2007-01-13 15:06:32 +00:00

97 lines
3.0 KiB
C++

// Low-level functions for atomic operations: PA-RISC version -*- C++ -*-
// Copyright (C) 2002, 2004, 2005 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 2, 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 COPYING. If not, write to the Free
// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
// USA.
// As a special exception, you may use this file as part of a free software
// library without restriction. Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License. This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.
#include <bits/c++config.h>
#include <ext/atomicity.h>
_GLIBCXX_BEGIN_NAMESPACE(__gnu_cxx)
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)
{
_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)
{
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