devhawala
commented
2 years ago Hello,
the following is from memory:
- there is an article about LOOM in the "green book", it is not detailled enough for an implementation, but gives an idea of the concepts and defines the important words
- i did not search for LOOM-things in the Smalltalk sources of the Analyst, but i remember that there is not the complete source code (but not remembering which parts i was looking for and did not find)
- at bitsavers there is the document Dlion_stklst.pdf (and a second one) which has some microcode sources and also some Mesa sources of the Smalltalk interpreter; the microcode source has some comments about the bits in the object table for Stretch and LOOM, but the code-details are missing (i believe), specifically about the decisions about when to move an object from "living" to "swapped-out" (including the transition states) and the interaction with garbage-collection
- i think i was lucky enough to create the image-converter from Stretch+LOOM to Stretch-alone for running the Analyst system
Maybe it would be easier (relatively, surely not absolutely) to extend the current architecture/implementation of the DV6-capable ST80 to use 32-bit words (instead of 16-bit) for memory and objecttable-fields, but leave anything else unchanged: most things use the lower 16 bits of a 32-bit word (arithmetic etc.), except for object-pointers (aka objecttable-indices) and pointers from the objecttable into memory, allowing for more objects and enough data memory.
Not a mature concept, just a very wild speculation...
So surely not a thing available soon, no matter which path is chosen.
Greetings Hans
iblowmymind
Hello,
I've also been interested in Smalltalk recently, especially older versions (Squeak seems just too bloated!)
Would LOOM be possible to implement here? Was it documented in a PDF in Bitsavers? (There should at least be sources for the Smalltalk-side implementation of LOOM in Analyst sources) If yes, would it be difficult to implement?