compiler optimization

Matt Godbolt, creator of Compiler Explorer, tours surprising optimizations modern compilers perform, such as turning loops into closed-form sums and using popcount instructions. He explores what the compiler does behind the scenes.

Matt Godbolt's CppCon 2017 talk shows what modern compilers do with your C++ code, using Compiler Explorer to inspect generated assembly. It covers surprising optimizations and how the tool works.

A two-hour live stream in which Aaron Hsu explains the architecture, design history and aesthetic of Co-dfns, his parallel APL compiler. He walks through the code and the reasoning behind its dense style.

Anders Hejlsberg whiteboards how compilers are taught versus how modern ones are actually built. He explains the shift to compilers as services with incremental, error-tolerant, IDE-oriented design, as in Roslyn and TypeScript.

Matt Godbolt tells the story of Compiler Explorer, from a hacky basement server to a cloud-scaled service handling tens of thousands of daily requests. He also shows its features and how it is built.

A long Mill Computing lecture on the Mill CPU's compiler toolchain, covering the specializer that targets family members, scheduling and latency passes, and the belt. It explains how the compiler handles a wide-issue, exposed-pipeline design.

Andy Keep's Clojure/Conj talk on writing a nanopass compiler, built from many single-task passes with formally defined intermediate languages. It covers the framework's origins in a compiler teaching course at Indiana University.

Chandler Carruth's CppNow 2013 keynote on how C++ builds complex software from simple emergent structures, and how compilers optimize them through inlining and value semantics.

Martin Odersky's JVM Language Summit 2015 talk argues that compilers can be thought of as databases. It describes design ideas for the Scala compiler and for developer tools.

Lex Fridman interviews Chris Lattner, creator of LLVM, Clang and Swift, about compilers, Swift for TensorFlow, TPUs and ML accelerators. The talk covers how hardware and software meet to produce efficient code.

Chandler Carruth's CppCon 2016 talk tries to defuse the heated debate over undefined behavior in C and C++. He explains from the compiler writer's perspective why UB exists and how it enables optimization.

The first episode of a long live-coding series in which Immo Landwerth builds the Minsk compiler for a small language in C#. It starts with a basic expression evaluator and builds toward a full language.

Jason Turner's CppCon 2016 talk builds a simple Commodore 64 game using C++17, showing how constexpr and const let a modern compiler produce tight 6502 code. He walks through assembly output to show abstractions being optimized away.

Tom7 explains how he built a SIGBOVIK 2017 paper made only of printable ASCII bytes that is also a valid DOS executable. He writes a C compiler targeting printable x86 without self-modifying code and solves the puzzles the constraint creates.

Jan Vitek of Northeastern University gives a meetup talk on the challenges of making the R language run fast. He explains what in R's semantics makes it hard to optimize and to build a JIT compiler for.

Chandler Carruth's GoingNative 2012 talk on Clang, covering how the compiler helps defend C++ code from mistakes. It makes the case for Clang's diagnostics and tooling.

Paul Phillips, a former Scala core contributor, argues after moving a million lines of code that much of what the software industry does is wrong. He critiques Scala and compiler design and calls for better approaches.

Nicholas Ormrod's CppCon 2016 talk on how Facebook optimizes std::string with its open-source replacement fbstring. It covers storage layout tradeoffs, small string optimization and memory allocation behavior.

Chandler Carruth walks through tuning C++ performance, from writing benchmarks to analyzing results on real CPUs and compilers. It focuses on small-scale problems such as loop kernels, data structures and algorithms, and on keeping compilers from optimizing benchmarks away.

Andrei Alexandrescu's ACCU 2016 talk previews material from his book on writing fast code, with a focus on optimization techniques such as sentinels and faster search.

Svelte creator Rich Harris explains moving reactivity into the compiler and language rather than tracking state at runtime, with a history of spreadsheets as reactive systems and comparisons to React.

Cliff Click, author of HotSpot's JIT compiler, shares hard-won advice for people writing virtual machines at the VMSS16 workshop. Topics include interpreters, JITs and performance lessons.

Paul Phillips, a major Scala compiler contributor, gives a long talk on Scala collections and views, using it to critique Scala's design and direction.

Swift compiler engineers explain how Swift implements generics using dictionary-passing with reified type metadata. They compare it with Java-style uniform representation and C++ or Rust monomorphization.

Christian Schafmeister presents CANDO at the 2016 European Lisp Symposium. It is a compiled Lisp-based language for designing macromolecules and nanoscale materials, built on the Clasp implementation of Common Lisp.

Jonathan Blow gives a formal, hour-long demo of his Jai compiler focused on the implicit context feature. The context carries things like allocators through a program without explicit parameter passing, and the talk walks through the code.

Christian Schafmeister presents lessons from six years of implementing Clasp, a Common Lisp compiler using LLVM as its backend that interoperates with C++. He explains handling a dynamic, memory-managed language on LLVM.

Chris Thalinger of Twitter describes the company's effort to run its Scala services on the Graal JIT compiler at Scala Days NYC 2018. It covers the performance gains Twitter saw and the work of running Graal in production.

Morphcat Games explains how they fit Micro Mages, a full-featured NES game, into 40 kilobytes. It covers compression of sprites and level layouts and other space-saving tricks.

David Schachter describes how he made a data-collection Python program run 114,000 times faster, drawing on decades of experience. The talk covers pipelining, cache effects and other optimization lessons.

Simon Peyton Jones explains nested data parallelism and Data Parallel Haskell, an approach to exploiting multicore and distributed hardware while keeping a simple single-control-flow programming model.

Andrew Adams, a Halide developer, presents the Halide language for image processing and tensor computation. The talk explains the separation of algorithm from schedule with illustrated examples of parallelism, locality and redundancy tradeoffs.

Rob Pike's GopherCon 2016 talk on the design of the Go assembler, explaining why Go uses a common assembly language translated to each architecture.

Chris Seaton talks about JRuby+Truffle, explaining how the Truffle and Graal combination optimises the tricky parts of Ruby and why it outperforms other Ruby implementations.

Robert Smith of Rigetti Computing talks at a Bay Area Lisp and Scheme meetup about using Common Lisp for quantum computing. He covers the technical, sociological and psychological sides of working across disciplines.

Christian Thalinger presents at the 2015 JVM Language Summit on adding ahead-of-time compilation to the JVM, covering the HotSpot team's AOT work and its relation to warmup and deoptimization.

Derek Slager's Clojure/conj talk argues that ClojureScript is a pragmatic choice for web development. He addresses common objections, recent improvements, tooling and use cases where it shines.

Christian Schafmeister's Google Tech Talk on designing spiroligomer molecules and building Clasp, a Common Lisp on LLVM that interoperates with C++, to program molecular design. It covers the chemistry, automatic differentiation for force fields, and how the compiler is built.

Christopher Domas's Derbycon 2015 talk on the M/o/Vfuscator, a compiler that emits only x86 mov instructions, showing mov is Turing complete. It explains how a full machine is built from mov and why the output is a nightmare to reverse engineer.

Part two of a Computer History Museum oral history with Gary Davidian, covering his work on the 68000 emulator for PowerPC at Apple, Power Computing, clean-room contracting and later performance optimization work. It is nearly three hours long.