llvm dev - Nov 2016 - RV: A Unified Region Vectorizer for LLVM - now on github

Hi LLVM developers,

The Region Vectorizer (RV) is now available on github 
https://github.com/simoll/rv

RV is a general-purpose vectorization framework for LLVM. It provides a 
unified interface to vectorize code regions, such as inner and outer 
loops, up to whole functions. Being a vectorization framework, RV is not 
another vectorization pass but rather enables users to vectorize IR 
directly from their own code.

I had a poster [1] and a lightning talk on RV at this year's US LLVM 
Developers' Meeting.


We are hoping to upstream (parts of) RV eventually. As a first step I 
propose to optimize the if-conversion phase in LLVM's LoopVectorizer. RV 
features a capable vectorization analysis that finds out which branches 
in a vectorized region can stay despite the surrounding loop being 
vectorized. Those uniform branches do not need to be folded giving an 
immediate benefit over the complete if conversion LoopVectorizer is 
doing right now.

We will submit patches that integrate a stripped-down version of RV into 
the LoopVectorizer to make minimal if conversion work.

Get in touch with me if you are interested in RV. We want to learn about 
new use cases and how RV could be improved. Finally, we welcome new 
developers to the project to work on new features or improve the 
existing codebase.

Regards,
Simon

[1] "RV: A Unified Region Vectorizer for LLVM", Moll, S. (LLVM US
DevMtg
'16) (docs/poster_rv.pdf in the github repository)


-- 

Simon Moll
Researcher / PhD Student

Compiler Design Lab (Prof. Hack)
Saarland University, Computer Science
Building E1.3, Room 4.31

Tel. +49 (0)681 302-57521 : moll at cs.uni-saarland.de
Fax. +49 (0)681 302-3065  : http://compilers.cs.uni-saarland.de/people/moll

----- Original Message -----
> From: "Simon Moll via llvm-dev" <llvm-dev at
lists.llvm.org>
> To: llvm-dev at lists.llvm.org
> Sent: Monday, November 21, 2016 2:35:50 AM
> Subject: [llvm-dev] RV: A Unified Region Vectorizer for LLVM - now on
github
> 
> Hi LLVM developers,
> 
> The Region Vectorizer (RV) is now available on github
> https://github.com/simoll/rv
> 
> RV is a general-purpose vectorization framework for LLVM. It provides
> a
> unified interface to vectorize code regions, such as inner and outer
> loops, up to whole functions. Being a vectorization framework, RV is
> not
> another vectorization pass but rather enables users to vectorize IR
> directly from their own code.
> 
> I had a poster [1] and a lightning talk on RV at this year's US LLVM
> Developers' Meeting.
> 
> 
> We are hoping to upstream (parts of) RV eventually. As a first step I
> propose to optimize the if-conversion phase in LLVM's LoopVectorizer.
> RV
> features a capable vectorization analysis that finds out which
> branches
> in a vectorized region can stay despite the surrounding loop being
> vectorized. Those uniform branches do not need to be folded giving an
> immediate benefit over the complete if conversion LoopVectorizer is
> doing right now.
> 
> We will submit patches that integrate a stripped-down version of RV
> into
> the LoopVectorizer to make minimal if conversion work.
As I said in person at the dev meeting, this sounds like a good incremental
step. I look forward to the patches.

 -Hal
> 
> Get in touch with me if you are interested in RV. We want to learn
> about
> new use cases and how RV could be improved. Finally, we welcome new
> developers to the project to work on new features or improve the
> existing codebase.
> 
> Regards,
> Simon
> 
> [1] "RV: A Unified Region Vectorizer for LLVM", Moll, S. (LLVM US
> DevMtg
> '16) (docs/poster_rv.pdf in the github repository)
> 
> 
> --
> 
> Simon Moll
> Researcher / PhD Student
> 
> Compiler Design Lab (Prof. Hack)
> Saarland University, Computer Science
> Building E1.3, Room 4.31
> 
> Tel. +49 (0)681 302-57521 : moll at cs.uni-saarland.de
> Fax. +49 (0)681 302-3065  :
> http://compilers.cs.uni-saarland.de/people/moll
> 
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
> 
-- 
Hal Finkel
Lead, Compiler Technology and Programming Languages
Leadership Computing Facility
Argonne National Laboratory