/* Glaurung, a UCI chess playing engine. Copyright (C) 2004-2008 Tord Romstad Glaurung 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 of the License, or (at your option) any later version. Glaurung 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 program. If not, see . */ #if !defined(LOCK_H_INCLUDED) #define LOCK_H_INCLUDED // x86 assembly language locks or OS spin locks may perform faster than // mutex locks on some platforms. On my machine, mutexes seem to be the // best. //#define ASM_LOCK //#define OS_SPIN_LOCK #if defined(ASM_LOCK) typedef volatile int Lock; static inline void LockX86(Lock *lock) { int dummy; asm __volatile__("1: movl $1, %0" "\n\t" " xchgl (%1), %0" "\n\t" " testl %0, %0" "\n\t" " jz 3f" "\n\t" "2: pause" "\n\t" " movl (%1), %0" "\n\t" " testl %0, %0" "\n\t" " jnz 2b" "\n\t" " jmp 1b" "\n\t" "3:" "\n\t":"=&q"(dummy) :"q"(lock) :"cc"); } static inline void UnlockX86(Lock *lock) { int dummy; asm __volatile__("movl $0, (%1)":"=&q"(dummy) :"q"(lock)); } # define lock_init(x, y) (*(x) = 0) # define lock_grab(x) LockX86(x) # define lock_release(x) UnlockX86(x) # define lock_destroy(x) #elif defined(OS_SPIN_LOCK) # include typedef OSSpinLock Lock; # define lock_init(x, y) (*(x) = 0) # define lock_grab(x) OSSpinLockLock(x) # define lock_release(x) OSSpinLockUnlock(x) # define lock_destroy(x) #elif !defined(_MSC_VER) # include typedef pthread_mutex_t Lock; # define lock_init(x, y) pthread_mutex_init(x, y) # define lock_grab(x) pthread_mutex_lock(x) # define lock_release(x) pthread_mutex_unlock(x) # define lock_destroy(x) pthread_mutex_destroy(x) #else # include typedef CRITICAL_SECTION Lock; # define lock_init(x, y) InitializeCriticalSection(x) # define lock_grab(x) EnterCriticalSection(x) # define lock_release(x) LeaveCriticalSection(x) # define lock_destroy(x) DeleteCriticalSection(x) #endif #endif // !defined(LOCK_H_INCLUDED)