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Re: [f-cpu] dynamic code reuse (fwd)

On Tue, Dec 09, 2003 at 10:47:07PM -0800, Raj Mahajan wrote:
> I read part of this paper... my main take-aways are as follows:
> 1) Instructions are often repeated verbatim.  This happens for many reasons
> which are often difficult to address in the code or the compiler.

As far as I remember, the address of the instruction is used to find
the cache entry.  That is, caching won't work with repeated
instructions (like function pro/epilogue boilerplate and such).

But hey... I've found something to improve ;)

> 2) Caching previous results of instructions can help by avoiding
> re-computing complex instructions unnecessarily.

Emphasis on _complex_, yes.

The real problem -- and the reason why dynamic code reuse is not
useful for FC0 -- is that you need an OOO core with all bells,
whistles and gongs.  In our current design, we can't deal with the
fact that a result may be available ahead of time.  Maybe later.

 Michael "Tired" Riepe <Michael.Riepe@stud.uni-hannover.de>
 "All I wanna do is have a little fun before I die"
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