Efficient online optimization by utilizing offline analysis and the safeTSA representation

Abstract

Conventional mobile-code representations, e.g. Java bytecode, provide machine-independence and type-safety, but do so at the expense of performance. This performance hit can be taken in the form of decreased throughput or in increased latency. SafeTSA was designed to reduce this performance hit, especially when producing high-quality optimized machine code. It does this by utilizing SSA form and thus shifting dataflow analysis effort from the online JIT compiler to the offline producer of the safeTSA program.This paper describes the extension of safeTSA to support a greater shifting of optimiza- tion effort away from the online JIT compiler, increase the performance, without sacrificing type-safety or machine-independence. Specifically, we describe mechanisms to reduce.the cost of online register allocation through offline analysis, and to use offline escape analysis so the online JIT compiler can produce less heap allocations.