ESPB: WASM-like bytecode interpreter for ESP32 with seamless FreeRTOS integration. Part 2: The JIT Compiler

Hi. Exactly 3 months have passed since the first publication. During this time, I’ve shaken things up significantly: I added a full-fledged JIT for Xtensa and RISC-V and implemented a heap of optimizations in the translator. I tested it on ESP32, ESP32-C3, and ESP32-C6 chips (the latter was tested on a residual basis—I only ran the main test; primary debugging was done on the first two). Here are the main innovations. 1. Fast Symbols: Killing strcmp in Linking Among the new features, I added Fast Symbols in addition to the standard symbol tables. These are two tables: one for system functions (ESP-IDF) and another custom one for your convenience. The core idea is that we remove the string name of functions from the binary, leaving only the pointer. This approach requires strict coordination between the table and the translator so that the translator knows exactly which index to use for calling a function via libffi. This reduces the space occupied in flash memory and eliminates the slo