Subj : Re: Memory visibility and MS Interlocked instructions
To   : comp.programming.threads
From : Chris Thomasson
Date : Sun Aug 28 2005 06:06 pm


> Will InterlockedExchange ensure that the ( fValueHasBeenComputed == TRUE )
> condition is not made visible "before" ComputeValues(...)'s effects are 
> made visible? Humm... This example of DCL "may" be busted on the writer's 
> end as well...

Humm, missed this part...


>>   The InterlockedExchange function ensures that the value of iValue is
>>   updated for all processors before the value of fValueHasBeenComputed is
>>   set to TRUE.

Note how it doesn't say anything about ComputeValue(...), it just says that 
iValue will be updated first. However, I guess that guarantees 
ComputeValue(...) effects will be fully visible before the flag is set. Does 
anyone totally trust that assertion, without disassembling the Interlocked 
API's?

;)

.