Firstly, all credits go to @ClassicHasClass for his great JIT support work for the v86 Firefox (basically baseline JIT is fully working). He had submitted the patches against upstream at
https://bugzilla.mozilla.org/show_bug.cgi?id=1860412 but unfortunately the patch has become stale and no longer work with post-140ESR codebase.
So after spending 3 weeks with help from few people in the PPC community and help of AI agents to track down errors pattern (lacking of tooling like rr-debugger made the work super hard - at one stage I was resolving to all sort of blind hypothesis and nearly gave up), I have successfully revived and fixed number of bugs of the original JIT codes. Please
check out https://github.com/runlevel5/firefox/pull/1 to all members here for reviewing.
TL;DR; LE path for POWER8, POWER9 and POWER10 is fully implemented (including ION JIT, WASM SIMD, JSPI and Simulator). The BE path and POWER10 optimization are still in progress atm. Please give JIT work a go and let me know if you happen to find any bug. I have tried my best to hand test and ran many stress test / benchmarks and have addressed quite a number of edge cases.
So what's next? Trying to get it polished as much as possible then get it upstreamed (for release 153 - why? new ESR would be branched off this version) or simply try to get the patch accepted in downstream sources like Fedora, Debian/Ubuntu.
