Ben Lippmeier

DPH - Data Parallel Haskell

Data Parallel Haskell is a long standing project to implement the flattening approach to Nested Data Parallelism (NDP) in an industrial strength compiler. Getting it working is one thing, but getting it fast is another. Gaze upon the current implementation and delight in the myriad ways that humans still don't understand computer science.

(wiki) Project Page
(paper) Data Flow Fusion with Series Expressions in Haskell
(paper) Vectorisation Avoidance
(paper) Work Efficient Higher-Order Vectorisation

GHC - The Glasgow Haskell Compiler

GHC is the industrial strength Haskell compiler. As a research associate at UNSW my main job was to help with the Data Parallel Haskell project. In Q1 2009 I spent three months working on the GHC on OpenSPARC project, where I repaired GHC's support for the SPARC architecture and benchmarked it on the highly multi-threaded UltraSPARC T2 (Niagra 2) architecture. In Q3 2007 I spent three months working at GHC HQ where I wrote a new graph coloring register allocator for the native code generator.

(blog) GHC on SPARC
(wiki) The GHC Register Allocator
(talk) Flattening and Replication in Data Parallel Haskell, FP-SYD May 2011
(talk) Beyond Haskell, HIW 2010
(talk) GHC on the OpenSPARC T2, (video), HIW 2009
(talk) Graph Colouring Register Allocation in the Glasgow Haskell Compiler, SAPLING November 2007

Photon Exchange

Video projections based on a hacked fluid flow simulator.

Serial Space 002, 27th July 2012

Collar Weights

Code and switching hardware for the Collar Weights mixed media installation. Inside each of the collars are electroluminescent lamps that are programmed to switch on, illuminating texts that become visible through the fabric. Phrases from interviews with the owners of the collars are played.
With Alexandra Gillespie and Somaya Langley.

Alex's photostream
Bathurst Regional Art Gallery, 7th August - 20th September 2009
Canberra Contemporary Art Space (CCAS) Gorman House, 7th February - 14th March 2009
Canberra Contemporary Art Space (CCAS) Manuka, 6th - 16th November 2008

AMPLE - An Abstract Machine for Parallel Lazy Evaluation

An experimental environment that can be used to study the behavior of parallel functional programs in terms of an abstract machine, without needing to worry about details specific to a native implementation. Can execute programs fully speculatively to determine the maximum embodied parallelism in a piece of code.

An AMPLE Implementation (source code)
Abstract Machine for Parallel Lazy Evaluation (AMPLE)
with Clem Baker-Finch, 2003

Sunshine II RISC CPU Simulator

A simulator for a classic 5 stage pipelined RISC processor. Visualisation of pipeline stalls, calculation of cpi, single step mode, breakpoints, instruction counts, memory mapped file and console IO. Pipeline setup is easy to change.

Darcs repository

High temperature superconducting microwave filters

Design and implementation of a filter intended to block interference that the Australia Telescope Compact Array was suffering from a nearby microwave distribution service (MDS). A summer vacation scholarship position, supervised by Russell Gough and Graham Gay of the Receivers Group.