Re: [gSoc] [graphite] general plan for Automatic parallelization in Graphite

[Tobias Grosser <tobi-grosser at web dot de>]

Hi Alex,

On Wed, 2009-04-22 at 08:19 -0700, Alex Turjan wrote:
> Are there any plans to move the partial unrolling phase from
> RTL to Tree-SSA?
> The move would benefit from better (or easier to implement) Tree-SSA alias analysis. 

We thought about loop unrolling in graphite.
It seems to be an interesting project and definitely possible in
general.
But at the moment I do not know of anybody who is working on this. So it
is an open project. If you want to work on this we will definitely
support you. ;-)

Tobi

> 
> Alex
> > 
> > 
> > 
> > 
> > --- On Wed, 4/22/09, Li Feng <nemokingdom@gmail.com>
> > wrote:
> > 
> > > From: Li Feng <nemokingdom@gmail.com>
> > > Subject: [gSoc] [graphite] general plan for Automatic
> > parallelization in   Graphite
> > > To: "GCC" <gcc@gcc.gnu.org>
> > > Cc: "Tobias Grosser"
> > <tobi-grosser@web.de>, "Sebastian"
> > <sebpop@gmail.com>, "Razya Ladelsky"
> > <RAZYA@il.ibm.com>, konrad.trifunovic@gmail.com
> > > Date: Wednesday, April 22, 2009, 5:10 PM
> > > Hi,
> > > 
> > > It's nice that the proposal 'Automatic
> > > parallelization in Graphite'
> > > is accepted. Which means I will be working with great
> > > Graphtie
> > > developers this summer, and trying to implement the
> > project
> > > .
> > > 
> > > I have set up a blog for this project, which will
> > mainly
> > > about this
> > > project: 1. plans 2. what I have done 3. related
> > Graphite
> > > internals
> > > You can subscribe to it if you like:
> > > http://summergraphite.blogspot.com/
> > > 
> > > Here is a general plan for this project, keep you in
> > loop,
> > > and feel free to comment :)
> > > 
> > >  1. Mark the innermost loop parallel  [done]
> > > 
> > >  2. Try to schedule autopar pass after Graphite, and
> > enable
> > >      code generation if flag_graphite_force_parallel
> > is set
> > >          - There should be some discussion with Razya
> > about
> > >            her plan about the autopar part
> > >          - But before that, I'll try to schedule
> > > autopar first
> > > 
> > >  3. I may try to write testcases for the loops that
> > should
> > > be
> > >      parallel, from simple to hard, and check
> > autopar's
> > > code
> > >      generation part, make sure this works correctly
> > as we
> > >      expected.
> > >          - The testcases is important. There should be
> > some
> > >            detailed discussion maybe with Sebastian
> > and
> > > Konrad.
> > >            To see what kind of loop we can/decide to
> > > handle.
> > >          - Check autopar's code generation with
> > >            flag_graphite_force_parallel set with these
> > > testcases,
> > >            report bugs if it goes wrong.
> > > 
> > >  4. Try to write code for deciding if a loop can be
> > > parallel
> > >      with data dependency test under this polyhedral
> > model.
> > >         - Try to understand the interface of data
> > > dependency test
> > >         - Write code, if data dependency success, mark
> > the
> > > loop parallel
> > > 
> > > Cheers,
> > > Li
> 
> 
>