When you want to do some computation on an FPGA, it is traditional to enter your design in a language like Verilog, and then to use automatic synthesis tools to turn your Verilog design into a "configuration bitstream" that can be fed to your FPGA to make it perform the computation you want. These synthesis… Continue reading Fuzzing FPGA synthesis tools
In this post, I'd like to share some thoughts I've accumulated over the past few years about how to draw better graphs. To get straight to the point, I have two concrete recommendations: normalised data should usually be plotted on a logarithmic scale, andscatter plots can be easier to understand than bar charts. I'll now… Continue reading A plot twist! Drawing better graphs in PL papers
A lot of papers include a graph that benchmarks the performance of a new technique against a technique from previous work. Such a graph might look like this: The graph is rather straightforward to read: when the green bar is higher, the old technique is faster, and when the red bar is higher, the new… Continue reading In praise of scatter plots
Many verification-oriented programming languages have built-in support for attaching loop invariants to loops. A loop invariant is a condition that holds in four different places: immediately before the loop, at the start of each iteration (before evaluating the test condition), at the end of each iteration, and immediately after the loop. Usually, the invariants are… Continue reading Loop invariants – where should we put them?
It was great to have Patrick Sittel visit our group earlier this year. This blog post is about the work he and I did during his visit, which has been accepted as a paper (co-authored with Martin Kumm and Peter Zipf) at ASP-DAC 2020. Suppose we wish to fit a row of tiles to a… Continue reading Modulo scheduling with rational initiation intervals
A huge number of academic papers, particularly in the fields of computer systems/architecture, use some sort of block diagram to give readers an overview of the solution being presented. For instance, about two thirds of the papers presented this year at ASPLOS contained at least one of these diagrams, usually towards the start of the paper.… Continue reading How to draw block diagrams
UK housebuilding specifications require all doors that lead from a habitable room to the outside to meet certain "fire door" criteria. These include having a self-closing mechanism, since fire doors are only effective when they are closed. Housebuilders typically implement this specification using a simple and discreet spring that pulls the door closed. This is… Continue reading A rant about fire doors
The music for this little-known James Bond song doesn't appear in any of the official songbooks, or indeed anywhere else on the internet as far as I can tell. So here's my attempt to rectify that. Never Say Never Again (1983) Music: Michel Legrand Lyrics: Lani Hall ----------------------------- Intro: Cm, F, etc. Cm F You… Continue reading Never Say Never Again – chords
I had a great time at PLDI 2018 last week. Here is my take on a few of the papers that stood out for me. John Vilk presented a tool called BLeak for finding memory leaks in web browsers. One might think that leak detection is not important in a garbage-collected setting, but Vilk explained… Continue reading Greatest hits of PLDI 2018
