Most virtual machines employ just-in-time (JIT) compilers to achieve
high-performance. Trace-based compilation and method-based compilation are two
major compilation strategies in JIT compilers. In general, the former excels
in compiling programs with more in-depth method calls and more dynamic
branches, while the latter is suitable for a wide range of programs. Some
previous studies have suggested that each strategy has its advantages and
disadvantages, and there is no clear winner.

In this paper, we present a new approach, namely, the meta-hybrid JIT
compilation strategy. It combines trace-based and method-based compilations to
utilize the advantages of both strategies. Moreover, it is realized as a meta
JIT compiler framework; thus, we can generate a VM with a hybrid JIT compiler
that can apply different program parts by merely writing an interpreter with
our framework.

We chose to extend a meta-tracing JIT compiler and supported the two
compilations on it. As a prototype, we implemented a simple meta-tracing JIT
compiler framework called BacCaml based on the MinCaml compiler by following
RPython’s architecture.

We evaluated its performance by creating a small functional programming
language with BacCaml and running microbenchmark programs. Furthermore, we
performed a synthetic experiment to confirm that there are programs that
run faster by hybrid compilation.