My understanding was always that self grew out of smalltalk? But I suppose the jit work in particular was developed for/in self?
https://dl.acm.org/doi/10.1145/800017.800542 "Efficient implementation of the smalltalk-80 system" by L. Peter Deutsch and Allan M. Schiffman in POPL '84: Proceedings of the 11th ACM SIGACT-SIGPLAN symposium on Principles of programming languages, January 1984, Pages 297–302
This motivated the creation of the ParcPlace spinoff to commercialize this technology. It was not the first JIT, but quite a few modern ones were inspired by it.
Self started out as one of the "Smalltalk-86" projects at Xerox PARC with Randy Smith collaborating with Berkeley's David Ungar. It was supposed to be a simpler and purer Smalltalk even if that made practical implementations impossible. But with David Ungar becoming a professor at Stanford, he found students that helped him make it possible, and eventually even much faster than existing Smalltalks. Craig Chambers worked on type inference for Self 1 and 2 and then Urs Hölzle worked on adaptive compilation with type feedback for Self 3 and 4.
https://dl.acm.org/doi/10.1145/191080.191116 "A third-generation SELF implementation: reconciling responsiveness with performance" by Urs Hölzle and David Ungar in OOPSLA '94: Proceedings of the ninth annual conference on Object-oriented programming systems, language, and applications, October 1994, Pages 229–243
This is the technology that became "Hot Spot" for Java. But very few virtual machines have this level of sophistication.
No, that was technology developed for the Self programming language which didn't have much in common with ST (see e.g https://dl.acm.org/doi/10.1145/1238844.1238853, there is also an interesting talk by Ungar and Smith). The same technology was also used for an ST dialect (Strongtalk) which was quickly discontinued in favor of Java Hotspot. The influence of ST is generally overstated.