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Re: machine learning for loop unrolling


Thank you everybody with the helpful input.

I ran into a small problem. I have some features ready (well, not
everything I wanted, but still good enough). I'm now trying to
instrument the resulting code to time each loop independently.
Essentially, what I want is to programatically modify loops from:

for (...)
{
}

to

s = clock()
for (...)
{
}
stuff += clock() - s

Of course, instead of clock(), I'd like to use a non-intrusive
mechanism. However, my research on this topic didn't lead to anything
but perfsuite, which doesn't work very well for me (should it?).

So here are the questions

- how can I actually insert the code (I need to do this during the
loop-unrolling phase, when the code is already in RTL form)?
- what performance measurement should I try?
- what other related work is out there?

Thanks,

Stefan Ciobaca

On 6/8/07, Stefan Ciobaca <stefan.ciobaca@gmail.com> wrote:
Hello everyone,

For my bachelor thesis I'm modifying gcc to use machine learning to
predict the optimal unroll factor for different loops (inspired from
this paper: http://www.lcs.mit.edu/publications/pubs/pdf/MIT-LCS-TR-938.pdf).


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