Perceus: Garbage Free Reference Counting with Reuse

  • Alex Reinking* ,
  • Ningning Xie* ,
  • Leonardo de Moura ,

The 42nd ACM SIGPLAN International Conference on Programming Language Design and Implementation (PLDI ’21) |

Published by ACM | Organized by SIGPLAN

(*) The first two authors contributed equally to this work. Distinguished paper at PLDI'21.

Extended version available as a technical report.

We introduce Perceus, an algorithm for precise reference counting with reuse and specialization. Starting from a functional core language with explicit control-flow, Perceus emits precise reference counting instructions such that programs are _garbage free_, where only live references are retained. This enables further optimizations, like reuse analysis that allows for guaranteed in-place updates at runtime. This in turn enables a novel programming paradigm that we call _functional but in-place_ (FBIP). Much like tail-call optimization enables writing loops with regular function calls, reuse analysis enables writing in-place mutating algorithms in a purely functional way. We give a novel formalization of reference counting in a linear resource calculus, and prove that Perceus is sound and garbage free. We show evidence that Perceus, as implemented in Koka, has good performance and is competitive with other state-of-the-art memory collectors.

论文与出版物下载

Koka

18 6 月, 2021

Koka: a Functional Language with Effects Koka is a strongly typed functional-style language with effect types and handlers.