[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: ATHLON performance tips


I could kick myself for being so stupid! Of course, Paul's solution
is an elegant solution! That happens when one writes without thinking...
Thank you Paul.
But why, Peter, do you want to expand your instructions artificially?



paul.meehan@amd.com wrote:
> Peter,
> You could bias the base address by subtracting a constant, and then use the
> offsets to add the constant back in. For example, if 132 is subtracted from
> the base address, then all the offsets will be bigger than 128. If the base
> address is known at compile time, then a biased base address could be
> computed at compile time. However, if the base address is passed in as an
> argument of a function, then biasing the base address would have to be done
> at run time, incurring the overhead of a sub instruction.
> Regards,
> Paul