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#include "compiler.h"
extern "C" {
#ifndef ATOMIC_OS_VERSION
// Inline assembly version
int AtomicAdd( int *pi, int v ){_CFE_;
int rv;
#ifdef GNU_INLINE_ASM
__asm__ __volatile__ (
"lock; xaddl %%eax, (%%ecx) \n"
: "=a"(rv)
: "c"(pi), "a"(v)
);
#elif defined(MSVC_INLINE_ASM)
// Assumption: Intel C compiler has same inline syntax as MSVC (?)
__asm {
mov ecx, pi
mov eax, v
lock xadd [ecx], eax
mov rv, eax
}
#else
#error No implementation of AtomicAdd
#endif
// After xaddl (exchange...) we have the previous value (on the stack).
// So add the increment and return.
return rv + v;
}
int AtomicIncrement( int *pi ){_CFE_;
int rv;
#ifdef GNU_INLINE_ASM
__asm__ __volatile__ (
"lock; xaddl %0, (%%ecx) \n"
: "=a"(rv)
: "c"(pi), "0" (1)
);
#elif defined(MSVC_INLINE_ASM)
// Assumption: Intel C compiler has same inline syntax as MSVC (?)
__asm {
mov ecx, pi
mov eax, 1
lock xadd [ecx], eax
mov rv, eax
}
#else
#error No implementation of AtomicAdd
#endif
// After xaddl (exchange...) we have the previous value (on the stack).
// So add the increment and return.
return rv+1;
}
int AtomicDecrement( int *pi ){_CFE_;
int rv;
#ifdef GNU_INLINE_ASM
__asm__ __volatile__ (
"lock; xaddl %0, (%%ecx) \n"
: "=a"(rv)
: "c"(pi), "0" (-1)
);
#elif defined(MSVC_INLINE_ASM)
// Assumption: Intel C compiler has same inline syntax as MSVC (?)
__asm {
mov ecx, pi
mov eax, -1
lock xadd [ecx], eax
mov rv, eax
}
#else
#error No implementation of AtomicAdd
#endif
// After xaddl (exchange...) we have the previous value (on the stack).
// So add the increment and return.
return rv-1;
}
int AtomicExchange( int *pi, int val ){_CFE_;
int rv;
#ifdef GNU_INLINE_ASM
__asm__ __volatile__ (
"lock; xchgl %0, (%%ecx) \n"
: "=a"(rv)
: "c"(pi), "0" (val)
);
#elif defined(MSVC_INLINE_ASM)
// Assumption: Intel C compiler has same inline syntax as MSVC (?)
__asm {
mov ecx, pi
mov eax, val
lock xchg [ecx], eax
mov rv, eax
}
#else
#error No implementation of AtomicAdd
#endif
return rv;
}
#else // ATOMIC_OS_VERSION
// Use OS function instead
#ifdef _WIN32
#include <windows.h>
#warning AtomicAdd is slow when adding values > 1
int AtomicAdd( int *pi, int v ){_CFE_;
// This is inefficient, but it does the job
// The primitive to add directly is not available
// in most Windows versions
int rv = *pi;
while( v<0 ){
rv = InterlockedDecrement( (long*)pi );
v++;
}
while( v>0 ){
rv = InterlockedIncrement( (long*)pi );
v--;
}
return rv;
}
int AtomicIncrement( int *pi ){_CFE_;
return InterlockedInccrement( (long*)pi );
}
int AtomicDecrement( int *pi ){_CFE_;
return InterlockedDecrement( (long*)pi );
}
int AtomicExchange( int *pi, int val ){_CFE_;
return InterlockedExchange( pi, val );
}
#endif // _WIN32
#endif // ATOMIC_OS_VERSION
} // extern "C"
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