Re: [boost] Re: [shared_ptr] possible bug in sp_counted_base.hpp

From: Peter Dimov (pdimov_at_[hidden])
Date: 2005-04-14 12:44:41

Rene Rivera wrote:
>> namespace boost
>> {
>>
>> namespace detail
>> {
>>
>> inline int atomic_exchange_and_add( int * pw, int dv )
>> {
>>    // int r = *pw;
>>    // *pw += dv;
>>    // return r;
>>
>>    asm
>>    {
>>        mov esi, [pw]
>>        mov eax, dv
>>        lock
>>        xadd [esi], eax
>>    }
>> }
>>
>> inline void atomic_increment( int * pw )
>> {
>>    //atomic_exchange_and_add( pw, 1 );
>>
>>    asm
>>    {
>>        mov esi, [pw]
>>        lock
>>        inc [esi]
>>    }
>> }

Everything looks correct to me, except I'd put the lock prefix before the 
instruction. GCC needs it on its own line but the x86 way is 'lock inc 
[esi]'.

Unless you can post a disassembly, I'm out of ideas. :-)