I am adding this to make it easy to determine if a SILFunction that is not inout
aliasable is captured. This is useful when emitting certain types of
diagnostics like I need to emit with move only.
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
This does not eliminate the entrypoints on SILBuilder yet. I want to do this in
two parts so that it is functionally easier to disentangle changing the APIs
above SILBuilder and changing the underlying instruction itself.
rdar://33440767
The SILGen testsuite consists of valid Swift code covering most language
features. We use these tests to verify that no unknown nodes are in the
file's libSyntax tree. That way we will (hopefully) catch any future
changes or additions to the language which are not implemented in
libSyntax.
Instead of appending a character for each substitution, we now prefix the substitution with the repeat count, e.g.
AbbbbB -> A5B
The same is done for known-type substitutions, e.g.
SiSiSi -> S3i
This significantly shrinks mangled names which contain large lists of the same type, like
func foo(_ x: (Int, Int, Int, Int, Int, Int, Int, Int, Int, Int, Int, Int))
rdar://problem/30707433
This ensures that ownership is properly propagated forward through the use-def
graph.
This was the work that was stymied by issues relating to SILBuilder performing
local ARC dataflow. I ripped out that local dataflow in 6f4e2ab and added a
cheap ARC guaranteed dataflow pass that performs the same optimization.
Also in the process of doing this work, I found that there were many SILGen
tests that were either pattern matching in the wrong functions or had wrong
CHECK lines (for instance CHECK_NEXT). I fixed all of these issues and also
expanded many of the tests so that they verify ownership. The only work I left
for a future PR is that there are certain places in tests where we are using the
projection from an original value, instead of a copy. I marked those with a
message SEMANTIC ARC TODO so that they are easy to find.
rdar://28685236
As in non-local scopes, local types and functions are generally
visible anywhere within enclosing braces, and it is up to capture
analysis to determine whether these entities attempt to capture an
entity that isn't guaranteed to be available.
There was a weird corner case with nested generic functions that
would fail in the SIL verifier with some nonsense about archetypes
out of context.
Fix this the "right" way, by re-working Sema function declaration
validation to assign generic signatures in a more principled way.
Previously, nested functions did not get an interface type unless
they themselves had generic parameters.
This was inconsistent with methods nested inside generic types,
which did get an interface type even if they themselves did not
have a generic parameter list.
There's some spill-over in SILGen from this change. Mostly it
makes things more consistent and fixes some corner cases.
Local functions may reference each other as long as they don't transitively capture any vars or other non-function local decls before their declaration.
Swift SVN r28394
Instead of immediately creating closures for local function declarations and treating them directly as capturable values, break function captures down and transitively capture the storage necessary to invoke the captured functions. Change the way SILGen emits calls to closures and local functions so that it treats the capture list as the first curry level of an invocation, so that full applications of closure literals or nested functions don't require a partial apply at all. This allows references among local functions with captures to work within the existing confines of partial_apply, and also has the nice benefit that circular references would work without creating reference cycles (though Sema unfortunately rejects them; something we arguably ought to fix.)
This fixes rdar://problem/11266246 and improves codegen of local functions. Full applications of functions, or immediate applications of closure literals like { }(), now never need to allocate a closure.
Swift SVN r28112