From 28f540f45bbacd939bfd07f213bcad2bf730b1bf Mon Sep 17 00:00:00 2001
From: Roland McGrath <roland@gnu.org>
Date: Sat, 18 Feb 1995 01:27:10 +0000
Subject: initial import

---
 sysdeps/mach/mips/machine-lock.h | 73 ++++++++++++++++++++++++++++++++++++++++
 1 file changed, 73 insertions(+)
 create mode 100644 sysdeps/mach/mips/machine-lock.h

(limited to 'sysdeps/mach/mips/machine-lock.h')

diff --git a/sysdeps/mach/mips/machine-lock.h b/sysdeps/mach/mips/machine-lock.h
new file mode 100644
index 0000000000..628aae41bb
--- /dev/null
+++ b/sysdeps/mach/mips/machine-lock.h
@@ -0,0 +1,73 @@
+/* Machine-specific definition for spin locks.  MIPS version.
+Copyright (C) 1994 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., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#ifndef _MACHINE_LOCK_H
+#define	_MACHINE_LOCK_H
+
+/* The type of a spin lock variable.  */
+
+typedef __volatile int __spin_lock_t;
+
+/* Value to initialize `__spin_lock_t' variables to.  */
+
+#define	__SPIN_LOCK_INITIALIZER	0
+
+
+#ifndef _EXTERN_INLINE
+#define _EXTERN_INLINE extern __inline
+#endif
+
+/* Unlock LOCK.  */
+
+_EXTERN_INLINE void
+__spin_unlock (__spin_lock_t *__lock)
+{
+  *__lock = 0;
+}
+
+/* Try to lock LOCK; return nonzero if we locked it, zero if another has.  */
+
+_EXTERN_INLINE int
+__spin_try_lock (register __spin_lock_t *__lock)
+{
+  register int __rtn;
+  __asm__ __volatile (".set noreorder");
+#if 0
+  __asm__ __volatile ("lw %0,0(%1)": "=r" (__rtn) : "r" (__lock));
+  __asm__ __volatile ("sw %0,0(%0)": : "r" (__lock));
+  __asm__ __volatile ("xor %0,%1,%0": "=r" (__rtn) : "r" (__lock));
+#else
+  /* Use the Mach microkernel's emulated TAS pseudo-instruction.  */
+  register int __rtn __asm__ ("a0");
+  __asm__ __volatile (".word 0xf ! %0 " : "=r" (__rtn) : "0" (__lock));
+#endif
+  __asm__ __volatile (".set reorder");
+  return __rtn ^ (int) __lock;
+}
+
+/* Return nonzero if LOCK is locked.  */
+
+_EXTERN_INLINE int
+__spin_lock_locked (__spin_lock_t *__lock)
+{
+  return *__lock != 0;
+}
+
+
+#endif /* machine-lock.h */
-- 
cgit 1.4.1