[dmd-concurrency] real

[Robert Jacques]

On Fri, 29 Jan 2010 11:06:11 -0500, Andrei Alexandrescu  
<andrei at erdani.com> wrote:

> Steve Schveighoffer wrote:
>> But on a 64 bit machine you will not.  Arrays are 128 bit items on 64
>> bit machines.  There are not 128-bit atomic operations on a 64 bit
>> machine.
>
> There are on some, which is exactly what makes the decision difficult  
> :o/. The rest of your assessment is correct.
>
> Andrei

Actually, atomic read/write is supported for aligned 128-bit values (via  
SSE2). It's just that some CPUs don't support unaligned atomic 128-bit  
reads.