This PR sets up the new integrated test/bench suite. It then migrates
all benchmarks and some related tests to the new suite. There's also
some documentation and some linting.
For now, a lot of the old tests are left alone so this PR doesn't become
even larger than it already is. Eventually, all tests should be migrated
to the new suite though so there isn't a confusing mix of two systems.
This PR implements zero cost `BaseIO` by erasing the `IO.RealWorld`
parameter from argument lists and structures. This is a **major breaking
change for FFI**.
Concretely:
- `BaseIO` is defined in terms of `ST IO.RealWorld`
- `EIO` (and thus `IO`) is defined in terms of `EST IO.RealWorld`
- The opaque `Void` type is introduced and the trivial structure
optimization updated to account for it. Furthermore, arguments of type
`Void s` are removed from the argument lists of the C functions.
- `ST` is redefined as `Void s -> ST.Out s a` where `ST.Out` is a pair
of `Void s` and `a`
This together has the following major effects on our generated code:
- Functions that return `BaseIO`/`ST`/`EIO`/`IO`/`EST` now do not take
the dummy world parameter anymore. To account for this FFI code needs to
delete the dummy world parameter from the argument lists.
- Functions that return `BaseIO`/`ST` now return their wrapped value
directly. In particular `BaseIO UInt32` now returns a `uint32_t` instead
of a `lean_object*`. To account for this FFI code might have to change
the return type and does not need to call `lean_io_result_mk_ok` anymore
but can instead just `return` values right away (same with extracting
values from `BaseIO` computations.
- Functions that return `EIO`/`IO`/`EST` now only return the equivalent
of an `Except` node which reduces the allocation size. The
`lean_io_result_mk_ok`/`lean_io_result_mk_error` functions were updated
to account for this already so no change is required.
Besides improving performance by dropping allocation (sizes) we can now
also do fun new things such as:
```lean
@[extern "malloc"]
opaque malloc (size : USize) : BaseIO USize
```
This PR makes `IO.RealWorld` opaque. It also adds a new compiler -only
`lcRealWorld` constant to represent this type within the compiler. By
default, an opaque type definition is treated like `lcAny`, whereas we
want a more efficient representation. At the moment, this isn't a big
difference, but in the future we would like to completely erase
`IO.RealWorld` at runtime.
