I am a human and programmer . I like to read books, take photos, and ride bikes in the hills near my house. I post things (and toot things ) about bread, legumes, and compilers. Right now, I am a software engineer working on compilers at Shopify and a Hacker in Residence at the Dartmouth College computer science…
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C-Reduce is a tool by Regehr and friends for minimizing C compiler bug reproducers. Imagine if you had a 10,000 line long C file that triggered a Clang bug. You don’t want to send a massive blob to the compiler developers because that’s unhelpful, but you also don’t want to cut it down to size by hand. The good news…
Every so often I come across a paper, blog post, or (occasionally) video that completely changes how I think about a topic in programming languages and compilers. For some of these posts, I can’t even remember how I thought about the idea before reading it—it was that impactful.
Two fun things happened recently and the proximity of the two made something go click in my head and now I think I understand how bytecode interpreters work.
Scrapscript is a small, pure, functional, content-addressable, network-first programming language. It’s designed to allow creating small, simply shareable programs. The language was created by Taylor Troesh and the main implementation was created by me and Chris.
*if you include word2vec.
Sometimes I just want to put pixels on a screen. I don’t want to think about SDL this or OpenGL that—I just want to draw my pixel buffer and be done.
Intro to HM
With some partial evaluation and specialization hints, it is possible to get pretty decent speedups on interpreters by turning them into compilers.
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What is Damas-Hindley-Milner?
CPS, or continuation-passing style, is an intermediate representation for programs, particularly functional programs. It’s used in compilers for languages such as SML and Scheme. Much of its utility comes from its support for tail calls and nonlocal control flow such as call/cc, but it can also be used as an…
I went on a little low-level Nix adventure yesterday and early this morning because of this excellent blog post. In it, Farid builds up the simplest possible Nix derivation—making a file that has the contents “hello world”. Here’s what I like about it:
We make micrograd fly with a little compiler magic. In this post, we’ll write a ML compiler from scratch.
Make parallel tasks print nicely with zero dependencies.
Compiling Lisp let expressions to x86-64
Tiger got to hunt, Bird got to fly; Lisper got to sit and wonder, (Y (Y Y))? Tiger got to sleep, Bird got to land; Lisper got to tell himself he understand. -- Kurt Vonnegut, modified by Darius Bacon
Compiling Lisp primitive unary functions to x86-64
Learn the command line, version control, build systems, and correctness in NEU’s CS 4973: ISDT.
Before I explain what I did to hurt poor Logan, I must explain our apartment’s media setup. You will see why shortly.
Optimizing compilers like to keep track of each IR instruction’s effects. An instruction’s effects vary wildly from having no effects at all, to writing a specific variable, to completely unknown (writing all state).
Adding a reader to our Lisp compiler
Overture to our small Lisp to x86-64 compiler
Static Single Assignment is a program representation where each “variable” (though this term can be misleading) is assigned exactly once. Mostly the variables aren’t variables at all, but instead names for values—for expressions. SSA is used a lot in compilers. See this lesson from Cornell for converting Bril to SSA…
With a little effort, you can make your mypy-typed Python go zoom.
Update: The paper version of this post is accepted at PLDI SOAP 2024. Take a look at the preprint (PDF).