34 lines
948 B
C
34 lines
948 B
C
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// Copyright (C) 2007 Id Software, Inc.
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//
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#ifndef __IDLIB_ATOMIC_H__
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#define __IDLIB_ATOMIC_H__
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class sdAtomic {
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public:
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static bool CompareAndSwap( volatile int* dest, int comperand, int exchange ); // atomic compare and swap, is a memory barrier
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};
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ID_INLINE bool sdAtomic::CompareAndSwap( volatile int* dest, int comperand, int exchange ) {
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#if defined( _XENON ) || defined( _WIN32 )
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return ( comperand == ::InterlockedCompareExchange( dest, exchange, comperand ) );
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#elif defined( __linux__ )
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// CHECKME: untested
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int old;
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__asm__ __volatile__ (
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"lock\n" \
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"cmpxchgl %2, %1\n" \
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: "a" (old), "=m" (*dest), \
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: "r" (exchange), "m" (*dest), "0" (comperand) \
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: "memory" );
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return old == comperand;
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#elif defined( MACOS_X )
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// can likely use the linux version above for osx-x86
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#error TODO: implement sdAtomic::CompareAndSwap
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#endif
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}
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#endif /* !__IDLIB_ATOMIC_H__ */
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