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Re: Volatile Memory accesses in Branch Delay Slots


> The function responsible for this behavior seems to be
> resource_conflicts_p in reorg.c. Sadly, I could not find any comments
> explaining why volatile accesses cannot be put into delay slots.
> 
> What is the reason for this behavior? I am unable to think of any
> situation where allowing volatile memory accesses in branch delay slots
> leads to problems. Am I missing a case? Or are negative effects limited
> to other architectures?

Delay slot filling is a code movement optimization and such optimizations are 
not valid for volatile memory accesses in the general case.

-- 
Eric Botcazou


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