73 lines
1.4 KiB
C
73 lines
1.4 KiB
C
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// locks.h - Thread synchronization primitives. SuperH implementation.
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/* Copyright (C) 2002 Free Software Foundation
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This file is part of libgcj.
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This software is copyrighted work licensed under the terms of the
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Libgcj License. Please consult the file "LIBGCJ_LICENSE" for
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details. */
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#ifndef __SYSDEP_LOCKS_H__
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#define __SYSDEP_LOCKS_H__
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typedef size_t obj_addr_t; /* Integer type big enough for object */
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/* address. */
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static unsigned char __cas_lock = 0;
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inline static void
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__cas_start_atomic (void)
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{
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unsigned int val;
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do
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__asm__ __volatile__ ("tas.b @%1; movt %0"
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: "=r" (val)
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: "r" (&__cas_lock)
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: "memory");
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while (val == 0);
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}
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inline static void
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__cas_end_atomic (void)
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{
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__asm__ __volatile__ (" " : : : "memory");
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__cas_lock = 0;
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}
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inline static bool
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compare_and_swap (volatile obj_addr_t *addr, obj_addr_t old,
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obj_addr_t new_val)
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{
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bool ret;
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__cas_start_atomic ();
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if (*addr != old)
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ret = false;
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else
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{
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*addr = new_val;
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ret = true;
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}
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__cas_end_atomic ();
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return ret;
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}
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inline static void
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release_set (volatile obj_addr_t *addr, obj_addr_t new_val)
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{
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__asm__ __volatile__ (" " : : : "memory");
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*(addr) = new_val;
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}
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inline static bool
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compare_and_swap_release (volatile obj_addr_t *addr, obj_addr_t old,
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obj_addr_t new_val)
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{
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return compare_and_swap (addr, old, new_val);
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}
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#endif /* ! __SYSDEP_LOCKS_H__ */
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