updated version of #22193
After #22029 and the followups #23983 and #24005 which fixed issues with
it, `tyFromExpr` no longer match any proc params in generic type bodies
but delay all non-matching calls until the type is instantiated.
Previously the mechanism `fauxMatch` was used to pretend that any
failing match against `tyFromExpr` actually matched, but prevented the
instantiation of the type until later.
Since this mechanism is not needed anymore for `tyFromExpr`, it is now
only used for `tyError` to prevent cascading errors and changed to a
bool field for simplicity. A change in `semtypes` was also needed to
prevent calling `fitNode` on default param values resolving to type
`tyFromExpr` in generic procs for params with non-generic types, as this
would try to coerce the expression into a concrete type when it can't be
instantiated yet.
The aliases `tyProxy` and `tyUnknown` for `tyError` and `tyFromExpr` are
also removed for uniformity.
This PR modifies `specializeResetT` so that it generates the proper
reset code for range types. I've tested it in the examples for issues
#23214 and #22462 as well as our codebase, and it seems to fix the
issues I had been experiencing.
Theoretical Benefits / Plans:
- Typed assembler-like language.
- Allows for a CPS transformation.
- Can replace the existing C backend by a new C backend.
- Can replace the VM.
- Can do more effective "not nil" checking and static array bounds
checking.
- Can be used instead of the DFA.
- Easily translatable to LLVM.
- Reasonably easy to produce native code from.
- Tiny memory consumption. No pointers, no cry.
**In very early stages of development.**
Todo:
- [x] Map Nim types to IR types.
- [ ] Map Nim AST to IR instructions:
- [x] Map bitsets to bitops.
- [ ] Implement string cases.
- [ ] Implement range and index checks.
- [x] Implement `default(T)` builtin.
- [x] Implement multi string concat.
- [ ] Write some analysis passes.
- [ ] Write a backend.
- [x] Integrate into the compilation pipeline.
* refactorings in preparation for ropes elimination of the C code generator; mostly the usual ': Rope' -> 'result: var Rope' rewrite
* rewrote ccgcalls.nim
* refactored ccgexprs.nim
* ccgliterals: refactoring
* refactoring: code dealing with name mangling
* refactoring: getRecordFieldsAux
* ropes are strings (insert obscene joke here)
* optimize JS code gen
* optimizations and code improvements
* more optimizations
* final cleanups
