>>>>> Geoffrey Keating writes:
Geoff> The documentation for the atomic operation patterns says things like:
>> This pattern must issue any memory barrier instructions such that the
>> pattern as a whole acts as a full barrier.
Geoff> Should the barrier happen before the operation, after the operation,
Geoff> are there two barriers, or is it undefined?
On PowerPC, this has a lot to do with the cooperation of the
various functions referencing the memory atomically. I am most familiar
with emitting sync (or lwsync) before the atomic operation.
David
