hello gcc 4.2.1 C preprocessor question, any clues are welcome;

[mm w]

ignore got it

On Mon, Aug 2, 2010 at 6:55 PM, mm w <0xcafefeed@gmail.com> wrote:
> gcc -v
> Using built-in specs.
> Target: i686-apple-darwin10
> Configured with: /var/tmp/gcc/gcc-5659~1/src/configure
> --disable-checking --enable-werror --prefix=/usr --mandir=/share/man
> --enable-languages=c,objc,c++,obj-c++
> --program-transform-name=/^[cg][^.-]*$/s/$/-4.2/
> --with-slibdir=/usr/lib --build=i686-apple-darwin10
> --program-prefix=i686-apple-darwin10- --host=x86_64-apple-darwin10
> --target=i686-apple-darwin10 --with-gxx-include-dir=/include/c++/4.2.1
> Thread model: posix
> gcc version 4.2.1 (Apple Inc. build 5659)
>
>
> -- BEGIN header OSAtomicLock.h
>
> #ifndef OSATOMICLOCK_H
> #define OSATOMICLOCK_H
>
> #if !defined(OS_INLINE)
>    #if defined(__GNUC__) && (__GNUC__ == 4) && !defined(DEBUG)
>        #define OS_INLINE static __inline__ __attribute__((always_inline))
>    #elif defined(__GNUC__)
>        #define OS_INLINE static __inline__
>    #elif defined(__cplusplus)
>                #define OS_INLINE static inline
>    #elif defined(_MSC_VER)
>        #define OS_INLINE static __inline
>    #elif defined(__WIN32__)
>                #define OS_INLINE static __inline__
>    #endif
> #endif
>
> #if defined(__WIN32__)
>        typedef __int32 OSAtomicLockLock;
>        #define OSAtomicLockInit 0
>        D_INLINE void __OSAtomicLockLock(volatile OSAtomicLock *LOCK) {
>        while (InterlockedCompareExchange((LONG volatile *)LOCK, ~0, 0) != 0) {
>                        Sleep(0);
>        }
>        }
>        D_INLINE void __OSAtomicLockUnlock(volatile OSAtomicLock *LOCK) {
>                MemoryBarrier();
>                *LOCK = 0;
>        }
> #elif defined(__APPLE__)
>        #include <libkern/OSAtomic.h>
>        typedef OSSpinLock OSAtomicLock;
>        #define OSAtomicLockInit OS_SPINLOCK_INIT
>        #define __OSAtomicLockLock(LOCK) ({ \
>                OSAtomicLock *lck_p = (LOCK); \
>                OSAtomicLock lck_v = *lck_p; \
>                if (0 != lck_v && ~0 != lck_v && (uintptr_t)lck_p != (uintptr_t)lck_v) { } \
>                OSSpinLockLock(lck_p); \
>        })
>        #define __OSAtomicLockUnlock(LOCK) ({ \
>                OSAtomicLock *lck_p = (LOCK); \
>                OSAtomicLock lck_v = *lck_p; \
>                if (~0 != lck_v && (uintptr_t)lck_p != (uintptr_t)lck_v) { } \
>                OSSpinLockUnlock(lck_p); \
>        })
> #else // means posix
>        #define _MULTI_THREADED
>        #include <pthread.h>
>        #if defined(__linux__)
>                #define OSAtomicLockInit PTHREAD_ADAPTIVE_MUTEX_INITIALIZER_NP
>        #else
>                #define OSAtomicLockInit PTHREAD_MUTEX_INITIALIZER
>        #endif
>        typedef pthread_mutex_t OSAtomicLock;
>        #define __OSAtomicLockLock(LOCK) ({ \
>                OSAtomicLock *lck_p = (LOCK); \
>                pthread_mutex_lock(lck_p); \
>        })
>        #define  __OSAtomicLockUnlock(LOCK) ({ \
>                OSAtomicLock *lck_p = (LOCK); \
>                pthread_mutex_unlock(lck_p); \
>        })
> #endif
>
> #define OSAtomicLockInitialize(LOCK) (LOCK = OSAtomicLockInit)
> #define OSAtomicLockLock(LOCK) __OSAtomicLockLock(LOCK)
> #define OSAtomicLockUnlock(LOCK) __OSAtomicLockUnlock(LOCK)
>
> #define OSAtomicAutoLock(LOCK, BLOCK) \
>        OSAtomicLockLock(LOCK); \
>        BLOCK \
>        OSAtomicLockUnlock(LOCK);
>
> #endif // OSATOMICLOCK_H
>
> /* HOWTO
>        static OSAtomicLock __myGlobalLock = OSAtomicLockInit;
>        void mylocalfunc()
>        {
>                OSAtomicLockLock(&__myGlobalLock);
>                //do stuff
>                OSAtomicLockUnlock(&__myGlobalLock);
>        }
> */
>
> -- END header OSAtomicLock.h
>
>
> -- BEGIN test1.c
>
> #include <stdio.h>
> #include "OSAtomicLock.h"
>
> static OSAtomicLock __myGlobalLock = OSAtomicLockInit;
>
> int main (int argc, const char** argv)
> {
>        OSAtomicLockLock(&__myGlobalLock);
>        fprintf(stderr,"hello\n");
>        OSAtomicLockLock(&__myGlobalLock);
>        return 0;
> }
>
> -- END test1.c
>
> -- BEGIN test2.c
>
> #include <stdio.h>
> #include "OSAtomicLock.h"
>
> static OSAtomicLock __myGlobalLock = OSAtomicLockInit;
>
> int main (int argc, const char** argv)
> {
>        OSAtomicAutoLock
>        (
>                &__myGlobalLock,
>                fprintf(stderr,"hello\n");
>        )
>        return 0;
> }
>
> -- END test2.c
>
> and the main thread blocked;
>
> -- BEGIN test1.S
>
> L2:
>        ...
>        movq    -24(%rbp), %rdi
>        call    _OSSpinLockUnlock
>        movl    $0, %eax
>        leave
>        ret
>
> -- END test1.S
>
> -- BEGIN test2.S
>
>
> L2:
>        ...
>        je      L5
> L5:
>        movq    -24(%rbp), %rdi
>        call    _OSSpinLockLock
>        movl    $0, %eax
>        leave
>        ret
>
> -- END test2.S
>
> and the main thread will bell;
>
> Best Regards
>