Implement SomSom, A Metacircular SOM

[smarr]

This PR implements SOM in SOM.
It's a pretty direct translation of the basic version of the SOM bytecode interpreter with 16 bytecodes.
It is able to execute all tests of the standard SOM test suite.
Though, it's pretty darn slow.

It also runs Hello World and probably some of the benchmarks, but I haven't confirmed this yet, because it's very very slow. Oops. I was running multiple levels of interpreters.

To run, it needs the primitives introduced in #67.
It may also need changes to how the command line arguments are handled so that the options are passed to SomSom and not consumed by the host SOM, for example see: smarr/TruffleSOM@7f0f26c

It should also be able to run multiple "storeys" of a tower of interpreters. Though, I haven't tested this recently. Yep. Works. See comment below.

Adoption/Integration Status

Status	SOM	PR
✅	SOM (java)	SOM-st/som-java#11
✅	TruffleSOM	SOM-st/TruffleSOM#53
	SOM++
	CSOM
	PySOM
	JsSOM
	SOM-RS
	ykSOM

PR History

Originally, this started out as a PR just for the lexer:
Implement the SOM Lexer in SOM.

This requires three new primitives and a new string escape code:

• String>>#isWhiteSpace
• String>>#isLetter
• String>>#isDigit
• and the \0 escape code, which should be pretty standard, but we haven't had need for it before

@sophie-kaleba could you review this please, too?

@ltratt I thought this might be of interest to you. Well, perhaps not quite yet, but, it's also a nice test case for the parser and string support logic.

[ltratt]

This slightly exceeds my ability to quickly understand, but one suggestion based on previous SOM tests experience is that it might be worth having a number of "negative" tests in here so that you can also ensure the lexer doesn't match things you don't think it should match. AFAICS it only has "positive" tests at the moment. Warning: I might be wrong.

[sophie-kaleba]

don't you need trusty as well for spec?

[sophie-kaleba]

I expect the CI to go red because of those tests, except for som-java once it will be updated.
Should we keep it red for now / allow failure for the others ?

[smarr]

Took a year, but SomSom seems to be read for merge.
PR description update.

It runs the SOM test suite, and hello world, and I think also itself, but haven't tested that recently.

@sophie-kaleba should be ready for experiments.

[smarr]

Towers of Interpreters: Hello World

Level 0:

/usr/bin/time -p ./som \
  -cp core-lib/Smalltalk ./Examples/Hello.som
Hello, World from SOM
real         4.37
user         3.00
sys          1.44

Level 1:

/usr/bin/time -p ./som \
  -cp core-lib/Smalltalk:core-lib/TestSuite:core-lib/SomSom/src/compiler:core-lib/SomSom/src/vm:core-lib/SomSom/src/vmobjects:core-lib/SomSom/src/interpreter:core-lib/SomSom/src/primitives \
  core-lib/SomSom/src/vm/Main.som \
  -cp core-lib/Smalltalk ./Examples/Hello.som
Hello, World from SOM
real         5.12
user         7.88
sys          1.58

Level 2:

/usr/bin/time -p ./som \
  -cp core-lib/Smalltalk:core-lib/TestSuite:core-lib/SomSom/src/compiler:core-lib/SomSom/src/vm:core-lib/SomSom/src/vmobjects:core-lib/SomSom/src/interpreter:core-lib/SomSom/src/primitives \
  core-lib/SomSom/src/vm/Main.som \
  -cp core-lib/Smalltalk:core-lib/TestSuite:core-lib/SomSom/src/compiler:core-lib/SomSom/src/vm:core-lib/SomSom/src/vmobjects:core-lib/SomSom/src/interpreter:core-lib/SomSom/src/primitives \
  core-lib/SomSom/src/vm/Main.som \
  -cp core-lib/Smalltalk ./Examples/Hello.som
Hello, World from SOM
real        41.95
user       106.31
sys          2.77

Level 3:

/usr/bin/time -p ./som \
  -cp core-lib/Smalltalk:core-lib/TestSuite:core-lib/SomSom/src/compiler:core-lib/SomSom/src/vm:core-lib/SomSom/src/vmobjects:core-lib/SomSom/src/interpreter:core-lib/SomSom/src/primitives \
  core-lib/SomSom/src/vm/Main.som \
  -cp core-lib/Smalltalk:core-lib/TestSuite:core-lib/SomSom/src/compiler:core-lib/SomSom/src/vm:core-lib/SomSom/src/vmobjects:core-lib/SomSom/src/interpreter:core-lib/SomSom/src/primitives \
  core-lib/SomSom/src/vm/Main.som \
  -cp core-lib/Smalltalk:core-lib/TestSuite:core-lib/SomSom/src/compiler:core-lib/SomSom/src/vm:core-lib/SomSom/src/vmobjects:core-lib/SomSom/src/interpreter:core-lib/SomSom/src/primitives \
  core-lib/SomSom/src/vm/Main.som \
  -cp core-lib/Smalltalk ./Examples/Hello.som
timed out...

Towers of Interpreters: TestSuite

Level 0:

/usr/bin/time -p ./som \
  -cp core-lib/Smalltalk ./TestSuite/TestHarness.som
Total number of tests:           115
Number of unsupported optionals: 2
Number of successful tests:      115
Number of assertions tested:     614
real         4.92
user         4.80
sys          1.65

Level 1:

/usr/bin/time -p ./som \
  -cp core-lib/Smalltalk:core-lib/TestSuite:core-lib/SomSom/src/compiler:core-lib/SomSom/src/vm:core-lib/SomSom/src/vmobjects:core-lib/SomSom/src/interpreter:core-lib/SomSom/src/primitives \
  core-lib/SomSom/src/vm/Main.som \
  -cp core-lib/Smalltalk ./TestSuite/TestHarness.som
Total number of tests:           115
Number of unsupported optionals: 0
Number of successful tests:      115
Number of assertions tested:     614
real         9.52
user        25.42
sys          2.11

Level 2:

/usr/bin/time -p ./som \
  -cp core-lib/Smalltalk:core-lib/TestSuite:core-lib/SomSom/src/compiler:core-lib/SomSom/src/vm:core-lib/SomSom/src/vmobjects:core-lib/SomSom/src/interpreter:core-lib/SomSom/src/primitives \
  core-lib/SomSom/src/vm/Main.som \
  -cp core-lib/Smalltalk:core-lib/TestSuite:core-lib/SomSom/src/compiler:core-lib/SomSom/src/vm:core-lib/SomSom/src/vmobjects:core-lib/SomSom/src/interpreter:core-lib/SomSom/src/primitives \
  core-lib/SomSom/src/vm/Main.som \
  -cp core-lib/Smalltalk ./TestSuite/TestHarness.som
Total number of tests:           115
Number of unsupported optionals: 0
Number of successful tests:      115
Number of assertions tested:     614
real       847.37
user      1015.02
sys         15.99