- In embedded Swift, classes get a simplified metadata: Basically just a vtable + destructor + superclass pointer.
- Only non-resilient (intended as permanent restriction), non-generic classes (for now) supported.
- Relax the check that prohibits metadata emission and usage to allow classes.
- Add a flag to the serialized module (IsEmbeddedSwiftModule)
- Check on import that the mode matches (don't allow importing non-embedded module in embedded mode and vice versa)
- Drop TBD support, it's not expected to work in embedded Swift for now
- Drop auto-linking backdeploy libraries, it's not expected to backdeploy embedded Swift for now
- Drop prespecializations, not expected to work in embedded Swift for now
- Use CMO to serialize everything when emitting an embedded Swift module
- Change SILLinker to deserialize/import everything when importing an embedded Swift module
- Add an IR test for importing modules
- Add a deserialization validation test
This adjusts Cxx to be built statically on all platforms including
Windows. The static library support is sufficient to support this
module linking statically on Windows.
Rewrite the handling for the `CxxStdlib` implicit linking to use a
slightly more functional style for filtering. Additionally, add Windows
to the list providing the overlay. The Windows linking scenario is a
slightly more complicated as the library names differ between static and
dynamic variants to disambiguate between import libraries and static
libraries. Take this into account when embedding the library name so
that the linker can find the appropriate content.
Moving the query implementation up to the AST library from SIL will allow
conveniences to be written on specific AST element classes. For instance, this
will allow `EnumDecl` to expose a convenience that enumerates element decls
that are available during lowering.
Also, improve naming and documentation for these queries.
`ReadOnly`/`ArgMemOnly` were mostly moved over, but a few were missed.
Update them all. Also default to `unknown` for no memory effects rather
than none (ie. we should be conservative).
Reformatting everything now that we have `llvm` namespaces. I've
separated this from the main commit to help manage merge-conflicts and
for making it a bit easier to read the mega-patch.
This is phase-1 of switching from llvm::Optional to std::optional in the
next rebranch. llvm::Optional was removed from upstream LLVM, so we need
to migrate off rather soon. On Darwin, std::optional, and llvm::Optional
have the same layout, so we don't need to be as concerned about ABI
beyond the name mangling. `llvm::Optional` is only returned from one
function in
```
getStandardTypeSubst(StringRef TypeName,
bool allowConcurrencyManglings);
```
It's the return value, so it should not impact the mangling of the
function, and the layout is the same as `std::optional`, so it should be
mostly okay. This function doesn't appear to have users, and the ABI was
already broken 2 years ago for concurrency and no one seemed to notice
so this should be "okay".
I'm doing the migration incrementally so that folks working on main can
cherry-pick back to the release/5.9 branch. Once 5.9 is done and locked
away, then we can go through and finish the replacement. Since `None`
and `Optional` show up in contexts where they are not `llvm::None` and
`llvm::Optional`, I'm preparing the work now by going through and
removing the namespace unwrapping and making the `llvm` namespace
explicit. This should make it fairly mechanical to go through and
replace llvm::Optional with std::optional, and llvm::None with
std::nullopt. It's also a change that can be brought onto the
release/5.9 with minimal impact. This should be an NFC change.
Macro-generated extensions are hoisted to file scope, because extensions are
not valid in nested scopes. Callers of 'visitAuxiliaryDecls' assume that the
auxiliary decls are in the same decl context as the original, which is clearly
not the case for extensions, and it leads to issues like visiting extension at
the wrong time during SILGen. The extensions are already added to the top-level
decls, so we don't need to visit them as auxiliary decls, and we can type-check
macro-expanded decls at the end of visitation in TypeCheckDeclPrimary.
- Renames ExperimentalPlatformCCallingConvention to
PlatformCCallingConvention.
- Removes non-arm calling convention support as this feature is working
around a clang bug for some arm triples which we hope to see resolved.
- Removes misleading MetaVarName from platform-c-calling-convention
argument.
- Replaces other uses of LLVM::CallingConv::C with
IGM.getOptions().PlatformCCallingConvention().
* Add @_used and @_section attributes for global variables and top-level functions
This adds:
- @_used attribute that flags as a global variable or a top-level function as
"do not dead-strip" via llvm.used, roughly the equivalent of
__attribute__((used)) in C/C++.
- @_section("...") attribute that places a global variable or a top-level
function into a section with that name, roughly the equivalent of
__attribute__((section("..."))) in C/C++.
When `-unavailable-decl-optimization=complete` is specified, skip emission of
resilient tag indices for enum cases that are marked unavailable with
`@available`.
Resolves rdar://109805050
The main change here is in IRGen which needs to be able to emit constant enum values.
Use `emitValueInjection` to create the enum constant.
Usually this method creates code in the current function.
But if all arguments to the enum are constant, the builder never has to emit an instruction.
Instead it can constant fold everything and just returns the final constant.
Also, create statically initialized let-globals as constant global (`constant` instead of `global`).
When `-unavailable-decl-optimization=complete` is specified, exclude
unavailable enum cases from the runtime layout of enums with payloads. Without
this, the type metadata for unavailable types may be referenced by enum cases
with unavailable payloads and cause linker failures.
Resolves rdar://107483852
When expanding a conformance macro, the generated extension decls are added to
the TopLevelDecls vector of the synthesized file unit to expose them to
sf->getSynthesizedFile()->getTopLevelDecls(). There are two problems with this:
1. These decls are also visited via visitAuxiliaryDecls() for the purpose of
type checking. This causes problems in code generation because the extensions
are visited separately, and because SIL and IRGen assume nested auxiliary decls
are members.
2. SILGen only emits top-level decls directly from the source file rather than its
synthesized file. Auxiliary decls are visited here, but this doesn't work for
nested conformance macros because the attached-to decl is not at the top-level,
so macro-generated conformances for nested types never emit their descriptor.
To fix this in the short term, visit top-level decls in the synthesized file that are
generated by conformance macros, and skip auxiliary extension decls when emitting type
members. This fix is narrowly scoped to only impact macros, but in the future this
warrants a more structural fix to better handle top-level decls in the synthesized file.
Partially address the incorrect handling for the `#dsohandle` on
Windows.
We were previously emitting a local definition for this external
constant, and worse yet, not marking the definition for COMDAT. It is
unclear what definition would win ultimately (implementation defined),
as we had a definition as well as the linker synthesized value. We can
change the SIL linkage for this type to `DefaultForDeclaration` which
will give it `available_externally` and default visibility and storage
which is closer to what we desire. However, because we do not track the
LLVM variables and apply heuristics for lowering the
`SILGlobalVariable`, we would attribute it with imported DLL Storage.
This would then cause us to fail at link time (amusingly enough link.exe
will report a LNK1000). Special case the variable and track that we are
targeting a windows environment in the `UniversalLinkageInfo` so that we
do not special case this on other platforms.
This also has the nice side effect of allowing us to remove the special
case in the TBD handling.
Fixes: #64741
This fixes an ld warning:
```
ld: warning: Could not find or use auto-linked library ‘swiftstd’
```
`swiftstd` was renamed to `swiftCxxStdlib`. We were still trying to link with `swiftstd` for some time to allow building with hosttools and to keep the CI green, however a new toolchain was released since the module was renamed, so this is no longer needed.
rdar://107412807
We'd still like to try to be forwardly compatible with future runtimes
that do properly handle noncopyable types, so emit them in a separate section from
copyable type records for now. This should prevent `_typeByName` from letting
someone get a hold of a noncopyable type's metatype as a (copyable) `Any.Type` and
then trying to use it to copy uncopyable values.
Always use `Decl::visitAuxiliaryDecls` to visit decls produced by macros, including peer macros and declaration macros. Use name-driven expansion for peer macros. Remove `MacroExpansionDecl::getRewritten()`.
Also make `ExpandMacroExpansionDeclRequest` cache the buffer ID (similar to other macros) instead of an array of decls.
Previously enum AccessLimitKind was
added to distinguish access scopes b/t package and public while keeping
DeclContext null but it proved to be too limiting. This PR creates package specific entries for DeclContext and
ASTHierarchy. It create a new class PackageUnit that can be set as the parent DeclContext of ModuleDecl. This PR
contains addition of such entries but not the use of them; the actual use of them will be in the upcoming PRs.
Resolves rdar://106155600
