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It's a rant and it's not information heavy. I've never heard of this processor (and provide a link, don't tell me to look it up). Other OO processors: Rekursiv

It's a rant and it's not information heavy. I've never heard of this processor (and provide a link, don't tell me to look it up). Other OO processors: Rekursiv (https://en.wikipedia.org/wiki/Rekursiv https://en.wikipedia.org/wiki/Rekursiv) and that famously slooow intel iAPX 432 (https://en.wikipedia.org/wiki/Intel_iAPX_432 https://en.wikipedia.org/wiki/Intel_iAPX_432) Interesting but neither (esp. the latter) were known as racehorses. I'd prefer to keep the hardware simple and fast and push the complexity into the software, and prove stuff. > would benefit from an HW/MMU architecture which focused on delivering fast object service, rather than flat address-spaces which software must then convert into objects. That conversion may not be cheap (edit: badly phrased, the object mapping process and hardware may not be cheaper (edit again: = faster) than that mapping done by the MMU for conventional memory) - can you exaplain how it would be done such that it would be cheaper in time than the current mapping in the common/hot/optimistic path, and how it would not be worse than it is now on the rare/cold/pessimistic path? And how it would behave on average, between those 2 extremes? And why objects everywhere would be better all-round?

klelatti 4y ago
On the subject of the iAPX 432 is anyone aware of an emulator? The only material I’ve seen is quite high level and doesn’t go down to ISA level.
p_l 4y ago
iAPX 432 arguably wasn't bad due to OOP orientation, but due to a bunch of several issues in how intel went about executing the idea. To the point that if they mismanaged a "normal" cpu this way they would have bungled it similarily.
kragen 4y ago
Probably if you haven't heard of CHERI and can't be bothered to Google it when one of the most respected systems architects around tells you it's worth looking at, you aren't going to put in the effort needed to read the CHERI tech reports so you can have an informed opinion on the performance cost of putting this kind of protection into hardware. And if the only historical "OO" processors you can think of are Rekursiv and iAPX432, and not the Dorado or the Symbolics line or the B5000/B5500/ClearPath line, it sounds like you have a lot of reading to do to get to having an informed opinion.
- zasdffaa 4y ago
  Symbolics was a tagged arch, not OO. Ditto Burroughs. They were not OO. Dunno about dorado.
  - kragen 4y ago
    The Symbolics 3600, the B5000, and the Smalltalk microcode for the Dorado all had generic operation dispatching in hardware, though they varied in how flexible it was. The iAPX432 and the Rational R1000, as far as I can tell, didn't. Generic late-bound operation dispatching is the essential core of OO. For many years AMD64 CPUs have had hardware acceleration for this sort of thing in the form of a "branch target buffer", so in this very important sense they're more OO than the iAPX432, though they don't have the hardware bounds-checking and dynamic type checking that all of the other architectures we're discussing did. Of these, only the Smalltalk microcode for the Dorado came close to the level of hardware support for OO that something like SiliconSqueak has. You're just repeating buzzwords rather than taking the time to understand what they refer to.
    - djmips 4y ago
      Starting a sentence with `You` is a signal to revaluate that sentence. It comes across as rude.
      - kragen 4y ago
        How would you suggest rephrasing a complete, sweeping dismissal of someone's comments, on the basis that they evidently have no relevant knowledge, so that it doesn't come across as rude?
        zasdffaa 4y ago
        I screwed up and I must apologise. I took a bad situation and made it worse. I have reasons but it shouldn't have happened. I am not happy that I clearly and unnecessarily annoyed you, and would prefer that we put out this fire and move on with a better mood for both of us, and hopefully I can do better next time. Again, I am genuinely sorry.

klelatti 4y ago

On the subject of the iAPX 432 is anyone aware of an emulator? The only material I’ve seen is quite high level and doesn’t go down to ISA level.

p_l 4y ago

iAPX 432 arguably wasn't bad due to OOP orientation, but due to a bunch of several issues in how intel went about executing the idea. To the point that if they mismanaged a "normal" cpu this way they would have bungled it similarily.

kragen 4y ago

Probably if you haven't heard of CHERI and can't be bothered to Google it when one of the most respected systems architects around tells you it's worth looking at, you aren't going to put in the effort needed to read the CHERI tech reports so you can have an informed opinion on the performance cost of putting this kind of protection into hardware. And if the only historical "OO" processors you can think of are Rekursiv and iAPX432, and not the Dorado or the Symbolics line or the B5000/B5500/ClearPath line, it sounds like you have a lot of reading to do to get to having an informed opinion.

zasdffaa 4y ago
Symbolics was a tagged arch, not OO. Ditto Burroughs. They were not OO. Dunno about dorado.
- kragen 4y ago
  The Symbolics 3600, the B5000, and the Smalltalk microcode for the Dorado all had generic operation dispatching in hardware, though they varied in how flexible it was. The iAPX432 and the Rational R1000, as far as I can tell, didn't. Generic late-bound operation dispatching is the essential core of OO. For many years AMD64 CPUs have had hardware acceleration for this sort of thing in the form of a "branch target buffer", so in this very important sense they're more OO than the iAPX432, though they don't have the hardware bounds-checking and dynamic type checking that all of the other architectures we're discussing did. Of these, only the Smalltalk microcode for the Dorado came close to the level of hardware support for OO that something like SiliconSqueak has. You're just repeating buzzwords rather than taking the time to understand what they refer to.
  - djmips 4y ago
    Starting a sentence with `You` is a signal to revaluate that sentence. It comes across as rude.
    - kragen 4y ago
      How would you suggest rephrasing a complete, sweeping dismissal of someone's comments, on the basis that they evidently have no relevant knowledge, so that it doesn't come across as rude?
      - zasdffaa 4y ago
        I screwed up and I must apologise. I took a bad situation and made it worse. I have reasons but it shouldn't have happened. I am not happy that I clearly and unnecessarily annoyed you, and would prefer that we put out this fire and move on with a better mood for both of us, and hopefully I can do better next time. Again, I am genuinely sorry.