The 80s is already 10 years later than my timeline, C had already gained massive momentum by then.
> Lisp was used to program massively parallel supercomputers
I'm curious to learn more about this, can you be more specific or provide links?
But anyhow, a massively parallel computer is a very different beast. Most computers used by people and enterprise were not massively parallel, and Lisps had poor performance on them and their architectures compared to C.
> Lisp stopped being slow a long, long time ago.
How long ago is that? I'd bet it was too little too late already. In my opinion, it would be somewhere along when Java came around, in the mid 90s. And even then, I'd say it was still too slow for most user application, but started being good enough for server work. At that point though, the momentum of C was already unstoppable, and Java became dominant, not CL.
It's the same story. Lisp ran on expensive early massively-parallel hardware, like the Connection Machine. But, again: exotic, expensive, few commercial users at the time, etc. Also killed by the AI winter.
From http://www.softwarepreservation.org/projects/LISP/maclisp_fa... , "This reports the results of a test in which a compiled MacLisp floating-point program was faster than equivalent Fortran code. The numerical portion of the code was identical and McLisp used a faster subroutine-call protocol."
I think this reinforces my thesis here. You can tell from the article that at the time, Lisp needed to prove itself in the mind of people as "fast enough". That seems to be the intent of the article. Given a good compiler, it may be just as fast.
I'm not trying to bash Lisp, I love lisp, I use it all the time. And when I say "fast enough", I know lisp is manageably fast, maybe custom hardware could have made it equally viable, maybe it only needed a more sophisticated compiler more widely available at an affordable price, but in practicality, it had more hurdle to overcome than other languages to meet the bar of the time.
Imagine an alternate reality where Lisp was clearly fastest. Where its semantics mapped very closely to commodity hardware of the time, and where Fortran, Algol, C, etc. semantics are all further removed from those hardware instructions, making them require more sophisticated compilers or very expensive specialty hardware to have them perform as well as Lisp. I feel it in such a reality, I can't see why C would have become the language of choice and not Lisp.
> From http://www.softwarepreservation.org/projects/LISP/maclisp_fa.... , "This reports the results of a test in which a compiled MacLisp floating-point program was faster than equivalent Fortran code. The numerical portion of the code was identical and McLisp used a faster subroutine-call protocol."
To add some more detail, the public description MACLISP floating point code being faster than Fortran, was published about 7 months before public unveiling of UNIX and when C was just taking more solid shape in it.
Lisp stopped being slow a long, long time ago.