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Date: Fri, 9 Aug 2013 02:48:48 +0200
From: Dániel Bali <>
Subject: Re: Daniel's weekly report #8

Hi Lukas

2013/8/9 Lukas Odzioba <>
> > - Generated binary for DES kernel and patched the instructions with NOPs
> Please try to add a brief description to the others that might read
> this why you're doing certain thing.
> This way your messages will be easier to understand.

First we wanted to use the Local Data Store, beacuse there is a ds_add_u64
instruction which might help to speed up 64bit addition. I failed at
getting the LDS working. The latest idea is to look at kernels that use DS
instructions and try to modify their code and get LDS working. If we had
that, we could maybe find out why the LDS didn't work on our dummy binary.

> > - I experimented with the kernel initialization process:
> >     - Tried to remove various lines from the beginning to see if I get
> error
> >     - Unfortunately I got an error almost all the time
> What kind of error is it?
> What enqueNDRange returns?

I should add a few lines of code that looks at the return value, this is a
good idea. I will report back when I have that (tomorrow).

> >     - It is not clear when an error occured. When it happens you usually
> get
> > the results of the last execution (maybe due to a lack of clean-up after
> the
> > previous exec)
> You might be right, you can try to overwrite results with some pattern
> like 0xdeafbeef to check that, but that's nothing important at the
> moment.

Yes, this is what I did when I was testing.

> >     - I didn't find any reference in any documents about the kernel's
> > initialization and what should be loaded from where - maybe I should look
> > further
> It might be impossible to find such things.
> Maybe try to review previous realhet's messages on AMD forum.
> Sice you have more knowledge now you can possibly understand more from
> them.

I will look around and try to search for some related terms on the forums


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