I have been meaning to do this change for a minute, but kept on putting it off.
This describes what is actually happening and is a better name for the option.
This code was updated for multiple return values (the SILValue in that case is a
MultipleInstructionResult and we can just ask those for their ownership kind).
In a previous commit, I banned in the verifier any SILValue from producing
ValueOwnershipKind::Any in preparation for this.
This change arises out of discussions in between John, Andy, and I around
ValueOwnershipKind::Trivial. The specific realization was that this ownership
kind was an unnecessary conflation of the a type system idea (triviality) with
an ownership idea (@any, an ownership kind that is compatible with any other
ownership kind at value merge points and can only create). This caused the
ownership model to have to contort to handle the non-payloaded or trivial cases
of non-trivial enums. This is unnecessary if we just eliminate the any case and
in the verifier separately verify that trivial => @any (notice that we do not
verify that @any => trivial).
NOTE: This is technically an NFC intended change since I am just replacing
Trivial with Any. That is why if you look at the tests you will see that I
actually did not need to update anything except removing some @trivial ownership
since @any ownership is represented without writing @any in the parsed sil.
rdar://46294760
* Remove apparently obsolete builtin functions.
- Remove s_to_u_checked_conversion and u_to_s_checked_conversion functions from builtin AST parsing, SIL/IR generation and from SIL optimisations.
* Remove apparently obsolete builtin functions - unit tests.
- Remove unit tests for SIL transformations relating to s_to_u_checked_conversion and u_to_s_checked_conversion builtin functions.
* Remove apparently obsolete builtin functions.
- Remove s_to_u_checked_conversion and u_to_s_checked_conversion functions from builtin AST parsing, SIL/IR generation and from SIL optimisations.
* Remove apparently obsolete builtin functions - unit tests.
- Remove unit tests for SIL transformations relating to s_to_u_checked_conversion and u_to_s_checked_conversion builtin functions.
This is in preparation for verifying that when ownership verification is enabled
that only enums and trivial values can have any ownership. I am doing this in
preparation for eliminating ValueOwnershipKind::Trivial.
rdar://46294760
Previously we would always calculate these instructions ownership dynamically
when asked and rely on the ownership verifier to catch if we made any
mistakes. Instead with this commit we move to a more static model where the
ownership that these instructions can take are frozen on construction. This is a
more static model that simplifies the ownership model.
I also eliminated a few asserts that are enforced in other places that caused
problems when parsing since we may not have a Function while Parsing (it was
generally asserts if a type was trivial).
`#assert` is a new static assertion statement that will let us write
tests for the new constant evaluation infrastructure that we are working
on. `#assert` works by lowering to a `Builtin.poundAssert` SIL
instruction. The constant evaluation infrastructure will look for these
SIL instructions, const-evaluate their conditions, and emit errors if
the conditions are non-constant or false.
This commit implements parsing, typechecking and SILGen for `#assert`.
This matches the name of OperandOwnership.cpp which performs an anologous
function. I also was able to eliminate an unneeded header. The key thing here
is that the only reason that we had ValueOwnershipKindClassifier.h was because
we needed some defs from it in SILValue.cpp for SILValue::getOwnershipKind()
... which is great except for the fact that ValueOwnershipKindClassifier is
basically the implementation of SILValue::getOwnershipKind().
So what this patch does is moves the implementation of
SILValue::getOwnershipKind() from SILValue.cpp -> ValueOwnership.cpp and then
puts the visitor into an anonymous namespace in that file.
I also added a little comment in SILValue.h that says that
SILValue::getOwnershipKind() is implemented in ValueOwnership.cpp, not
SILValue.cpp.
