[boost] Re: [shared_ptr] m68k and ia64 implementations by Ben Hutchings, RFC

From: Alexander Terekhov (terekhov_at_[hidden])
Date: 2005-04-07 07:58:08

Peter Dimov wrote:
[...]
>   ------------------------------------------------------------------------
>                                    Name: sp_counted_base_gcc_ia64.hpp
>    sp_counted_base_gcc_ia64.hpp    Type: Plain Text (text/plain)
>                                Encoding: 7bit

: inline void atomic_increment( long * pw )
: {
:     // ++*pw;
: 
:     long tmp;
: 
:     __asm__ ("fetchaddl %0=[%2],1" :
:              "=r"(tmp), "=m"(*pw) :
:              "r"(pw) :
:              );
: }

That's implicit .acq by default, right? 

Release incarnation is probably better. It merely "delays" increment
and doesn't hinder value prediction for subsequent loads and other
speculative stuff for "all" subsequent operations.

regards,
alexander.