Efficient and Verifiable Program Annotation for the Transport of Escape Information

JIT compilation is frequently employed in order to speedup the execution of platform-independent and dynamically extensible mobile code applications. Since the time required for dynamic compilation directly influences a program’s execution time, JIT compilers usu-ally utilize only simple and fast techniques for program analysis and optimization. Program annotations can be used to improve the analysis and optimization process of a JIT compiler. Program annotations allow a mobile code system to derive information about a program, on the producer side, and transmit that information along with the program to the consumer side. In this paper, we present an inherently safe annotation technique for the safe transmission of escape information. The annotation technique described in this paper is based on the SafeTSA mobile code format and is implemented as a simple extension of SafeTSA’s type system. The space required for these annotations is minimal, and measurements of compilation time show that using information from an offline escape analysis in form of program annotations is evidently faster than performing the escape analysis at runtime. 1