Re: Call for compiler help/advice: atomic builtins for v3

[Florian Weimer <fw at deneb dot enyo dot de>]

* Peter Dimov:

> Even on a P4, inlining may enable compiler optimizations. One case is when 
> the compiler can see that the return value of __sync_fetch_and_or (for 
> instance) isn't used. It's possible to use a wait-free "lock or" instead of 
> a "lock cmpxchg" loop (MSVC 8 does this for _InterlockedOr.)

You don't need inlining to optimize these cases.  You only need to
know precisely what the library implementations do, and you need a
couple of choices.  GCC can already optimizes

  printf ("hello world\n");

to

  puts ("hello world");

even though no inlining takes place.