gcc/libstdc++-v3/config/cpu/hppa/atomicity.h

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/* Low-level functions for atomic operations. PA-RISC version. -*- C++ -*-
Copyright 2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 of the
License, or (at your option) any later version.
The GNU C 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#ifndef _GLIBCXX_ATOMICITY_H
#define _GLIBCXX_ATOMICITY_H 1
typedef int _Atomic_word;
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
in src/misc-inst.cc when _GLIBCXX_INST_ATOMICITY_LOCK
is defined. */
#ifndef _GLIBCXX_INST_ATOMICITY_LOCK
template volatile int __Atomicity_lock<0>::_S_atomicity_lock;
#endif
static inline 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));
result = *__mem;
*__mem = result + __val;
/* Reset lock with PA 2.0 "ordered" store. */
__asm__ __volatile__ ("stw,ma %1,0(%0)"
: : "r" (&lock), "r" (tmp) : "memory");
return result;
}
static inline void
__attribute__ ((__unused__))
__atomic_add (_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));
*__mem += __val;
/* Reset lock with PA 2.0 "ordered" store. */
__asm__ __volatile__ ("stw,ma %1,0(%0)"
: : "r" (&lock), "r" (tmp) : "memory");
}
#endif