Otherwise, we can't represent a cross-reference to generic parameters
in a parent type /when used in an extension/.
https://bugs.swift.org/browse/SR-9084
Previously, the fast path for nested types only worked when the nested
type was defined in a Swift module or a Clang module without an
overlay; this is because it was originally designed to fix circularity
issues when merging partial modules for a single target. By having a
Swift overlay module pass through requests for nested types to the
underlying Clang module, we get the fast-path behavior in more cases.
(The one case where it /won't/ kick in is if the overlay has a nested
type that shadows a nested type from the Clang module, but that's
probably pretty rare!)
Generic environments and archetypes can be expensive to deserialize
if they involve a generic signature not seen before.
Also, canonicalize the witness substitutions to eliminate type
aliases, and map them to interface types, which again are cheaper
to deserialize.
Actually, the biggest win here seems to be not recording parameters,
which were taking up a ridiculous amount of space in the generated
swiftdoc. This change takes Swift.swiftdoc from 5MB to 3.5MB.
This is how we originally controlled whether or not we printed out ownership
annotations when we printed SIL. Since then, I have changed (a few months ago I
believe) the ownership model eliminator to know how to eliminate these
annotations from the SIL itself. So this hack can be removed.
As an additional benefit, this will let me rename -enable-sil-ownership to
-enable-sil-ownership-verifier. This will I hope eliminate confusion around this
option in the short term while I am preparing to work on semantic sil again.
rdar://42509812
Validation of the input side of FunctionTypeRepr was previously being done in Sema because of expression folding. If we instead push the invariant that the input TypeRepr should always be a TupleTypeRepr into the AST a number of nice cleanups fall out:
- The SIL Parser no longer accepts Swift 2-style type declarations
- Parse is more cleanly able to reject invalid FunctionTypeReprs
- Clients of the AST can be assured the input type is always a TupleType so we can flush Swift 2 hacks
Ideally `UnboundGenericType` should never be serialized but it is
currently allowed to make generic `typealias` declarations without
specifying generic parameters, so it should be allowed to cross
reference typealias decls in such types as well because `NameAliasType`
can't be used until generic parameters are resolved.
This is only a temporary fix and more comprehensive solution is still
pending here, most likely such declarations should not produce
`UnboundGenericType` but instead should copy generic parameters from
underlying type and produce proper `NameAliasType`.
Resolves: rdar://problem/37384120
This flag supports promoting KeyPath access violations to an error in
Swift 4+, while building the standard library in Swift 3 mode. This is
only necessary as long as the standard library continues to build in
Swift 3 mode. Once the standard library build migrates, it can all be
ripped out.
<rdar://problem/40115738> [Exclusivity] Enforce Keypath access as an error, not a warning in 4.2.
This is unfortunate in that it makes the linker do extra work, but in
practice it probably doesn't matter much, and meanwhile it handles all
our problems with @inlinable.
Alternate solution to rdar://problem/39338239
This reverts commit bb16ee049d,
reversing changes made to a8d831f5f5.
It's not sufficient to solve the problem, and the choices were to do
something more complicated, or just take a simple brute force
approach. We're going with the latter.
This reverts commit ee6e190e09. It's not
sufficient to solve the problem, and the choices were to do something
more complicated, or just take a simple brute force approach. We're
going with the latter.
LinkNormal mode is used by the mandatory pipeline. It only needs
to deserialize what is necessary for code generation, that is
functions with shared linkage that must be emitted into the client.
It was only used in a few tests. Those tests now use -emit-sil instead
of -emit-silgen, with some functions marked @_transparent and a few
CHECK: lines changed now that the mandatory optimizations get to run.
Continue to emit notes for the candidates, but use different text.
Note that we can emit a typo correction fix-it even if there are
multiple candidates with the same name.
Also, disable typo correction in the migrator, since the operation
is quite expensive, the notes are never presented to the user, and
the fix-its can interfere with the migrator's own edits.
Our general guidance is that fix-its should be added on the main
diagnostic only when the fix-it is highly likely to be correct.
The exact threshold is debateable. Typo correction is certainly
capable of making mistakes, but most of its edits are right, and
when it's wrong it's usually obviously wrong. On balance, I think
this is the right thing to do. For what it's worth, it's also
what we do in Clang.
Add serialization layouts for rare instructions that take extra attributes. We
can continue adding bits to these layout without affecting the layout of the
vast majority of instructions.
Introduce a new Type node, BoundNameAliasType, which describes a
reference to a typealias that requires substitutions to produce the
underlying type. This new type node is used both for references to
generic typealiases and for references to (non-generic) typealiases
that occur within generic contexts, e.g., Array<Int>.Element.
At present, the new type node is mainly useful in preserving type
sugar for diagnostics purposes, as well as being reflected in other
tools (indexing, code completion, etc.). The intent is to completely
replace NameAliasType in the future.
(currently spelled with an underscore to indicate its WIP state)
Later commits will handle imported enums correctly and implement the
checks for switch cases.
We can encounter these when the compiler modifies an inlinable
function to break apart a struct and the struct uses a private
type for one of its fields. It's questionable whether we /should/
handle this, but meanwhile this /is/ a non-intrusive fix that
preserves the performance of non-resilient libraries.
(That is, it appears this worked in Swift 4.0, though perhaps
not all of the same optimizations kicked in.)
https://bugs.swift.org/browse/SR-6874
This is technically a source break, but the @_fixed_layout attribute
is not official yet. If anyone really cares, we can make this
conditional on -swift-version 5 later, but I'd rather not.
This change is necessary so that we can give property initializers
non-public linkage. Currently they are public, because they can be
referenced from inlinable initializers.
Now that property initializers inside a @_fixed_layout type can
only reference public symbols, they no longer have to be public,
but making that change requires a bit more work.
For now these are underscored attributes, i.e. compiler internal attributes:
@_optimize(speed)
@_optimize(size)
@_optimize(none)
Those attributes override the command-line specified optimization mode for a specific function.
The @_optimize(none) attribute is equivalent to the already existing @_semantics("optimize.sil.never") attribute
When a conformance can either be synthesized or implied, we tend to prefer
implied. However, if the implied conformance comes from a deserialized
conformance, it will lead to an incomplete conformance and cause a crash.
This is a narrow fix for SR-6105 / rdar://problem/34911378.
