> The really difficult thing would be to write a new compiler backend with a coherent IR that everybody understands and you'll stick to.
But why would you bother, when with those same skills and a lot less time, you could fork LLVM, correct its IR semantics yourself (unilaterally), and then push people to use your fork?
(I.e. the EGCS approach to forcing the upstream to fix their shit.)
> This doesn's support the Fongulab Splox ZV406 processor made for six years in the 1980s, whereas LLVM does, therefore this is a waste of time.
AFAIK, the various Fongulab Sploxes that LLVM has targets for, are mostly there to act as forcing functions to keep around features that no public backend would otherwise rely on, because proprietary, downstream backends rely on those features. (See e.g. https://q3k.org/lanai.html — where the downstream ISA of interest is indeed proprietary, but used to be public before an acquisition; so the contributor [Google] upstreamed an implementation of the old public ISA target.)
Thanks for the link about Lanai although that site's cert has expired (very recently too) so it's slightly annoying (or of course bad guys are attacking me)
As to the first point, I suspect this is a foundational problem. Like, suppose you realise the concrete used to make a new skyscraper was the wrong mixture. In a sense this is a small change, there's nothing wrong with the elevators, the windows, cabling, furnishing, air conditioning, and so on. But, to "fix" this problem you need to tear down the skyscraper and replace it. Ouch.
I may be wrong, I have never tried to solve this problem. But I fear...
But why would you bother, when with those same skills and a lot less time, you could fork LLVM, correct its IR semantics yourself (unilaterally), and then push people to use your fork?
(I.e. the EGCS approach to forcing the upstream to fix their shit.)
> This doesn's support the Fongulab Splox ZV406 processor made for six years in the 1980s, whereas LLVM does, therefore this is a waste of time.
AFAIK, the various Fongulab Sploxes that LLVM has targets for, are mostly there to act as forcing functions to keep around features that no public backend would otherwise rely on, because proprietary, downstream backends rely on those features. (See e.g. https://q3k.org/lanai.html — where the downstream ISA of interest is indeed proprietary, but used to be public before an acquisition; so the contributor [Google] upstreamed an implementation of the old public ISA target.)