Modern compilera often implement function calls (or returns) in two steps: first, a "closure" environment is properly installed to provide access for free variables in the target program fragment; second, the control is transferred to the target by a "jump with arguments (or results)." Closure conversion - which decides where and how to represent closures at runtime - is a crucial step in the compilation of functional languages. This paper presents a new algorithm that exploits the use of compile-time control and data-flow information to optimize function calls. By extensive closure sharing and allocating as many closures in registers as possible, our new closure-conversion algorithm reduces heap allocation by 36% and memory fetches for local and global variables by 43%; and improves the already efficient code generated by an earlier version of the Standard ML of New Jersey compiler by about 17% on a DECstation 5000. Moreover, unlike most other approaches, our new closure-allocation scheme satisfies the strong safe-for-space-complexity rule, thus achieving good asymptotic space usage.
|Original language||English (US)|
|Number of pages||33|
|Journal||ACM Transactions on Programming Languages and Systems|
|State||Published - Jan 2000|
All Science Journal Classification (ASJC) codes
- D.3.3 [Programming Languages]: Language Constructs and Features - Procedures, functions, and subroutines
- D.3.4 [Programming Languages]: Processors - Compilers; optimization; closure conversion