Language support for regions

Abstract

Region-based memory management systems structure memory by grouping objects in regions under program control. Memory is reclaimed by deleting regions, freeing all objects stored therein. Our compiler for C with regions, RC, prevents unsafe region deletions by keeping a count of references to each region. Using type annotations that make the structure of a program's regions more explicit, we reduce the overhead of reference counting from a maximum of 27% to a maximum of 11% on a suite of realistic benchmarks. We generalise these annotations in a region type system whose main novelty is the use of existentially quantified abstract regions to represent pointers to objects whose region is partially or totally unknown. A distribution of RC is available at http://www.cs.berkeley.edu/~dgay/rc.tar.gz.

HPTA: High-performance text analytics

“…Region-based memory allocators aim to maximize performance by eradicating internal fragmentation and by efficiently de-allocating a large number of items in bulk [6,12,33]. Region-based memory allocation is effective when individually allocated items go out of scope at the same time, implying that their memory can be reclaimed at the same time.…”

“…Region-based memory management is generally provided using application-specific code [6,12]. Language support has been proposed [8,30] but is not widely available.…”

“…A downside of the word bank is that individual strings cannot be removed or de-allocated. This is a known limitation of region-based memory management [6,8,12]. We believe that this limitation is however not important for text analytics as remove operations are rare in this area.…”

A Retrospective on Region-Based Memory Management

“…Another line of related work includes the work by Aiken et al on extending C with explicit region annotations [22,23] and the work on Cyclone, a safe dialect of C [27,35].…”

Component Composition for Embedded Systems Using Semantic Aspect-Oriented Programming

“…Gay and Aiken's system provides an interesting contrast to ours in its overall approach [100]. They provide a safe, flat region-based system that allows arbitrary references between regions.…”