KeyPath's getter/setter/hash/equals functions have their own calling
convention, which receives generic arguments and embedded indices from a
given KeyPath argument buffer.
The convention was previously implemented by:
1. Accepting an argument buffer as an UnsafeRawPointer and casting it to
indices tuple pointer in SIL.
2. Bind generic arguments info from the given argument buffer while emitting
prologue in IRGen by creating a new forwarding thunk.
This 2-phase lowering approach was not ideal, as it blocked KeyPath
projection optimization [^1], and also required having a target arch
specific signature lowering logic in SIL-level [^2].
This patch centralizes the KeyPath accessor calling convention logic to
IRGen, by introducing `@convention(keypath_accessor_XXX)` convention in
SIL and lowering it in IRGen. This change unblocks the KeyPath projection
optimization while capturing subscript indices, and also makes it easier
to support WebAssembly target.
[^1]: https://github.com/apple/swift/pull/28799
[^2]: https://forums.swift.org/t/wasm-support/16087/21
The diagnostics/remarks out of the ModularizationError wrapped in a
TypeError (eg. coming from resolveCrossReference) is otherwise just
dropped but could help better understand C/C++ interop issues.
Plus tweak `DefaultDefinitionTypeRequest` caching to support querying the
cached type when dumping. This fixes a crash where type computation is
triggered in the dumper before import resolution in `-dump-parse` mode.
This attribute can be attached to a noncopyable struct to specify that its
storage is raw, meaning the type definition is (with some limitations)
able to do as it pleases with the storage. This provides a basis for
implementing types for things like atomics, locks, and data structures
that use inline storage to store conditionally-initialized values.
The example in `test/Prototypes/UnfairLock.swift` demonstrates the use
of a raw layout type to wrap Darwin's `os_unfair_lock` APIs, allowing
a lock value to be stored inside of classes or other types without
needing a separate allocation, and using the borrow model to enforce
safe access to lock-guarded storage.
Attribute @_silgen_name is today only allowed to be used on functions, this change allows usage on globals as well. The motivation for that is to be able to "forward declare" globals just like it's today possible to do with functions (for the cases where it's not practical or convenient to use a bridging header).
Separately, this change also adds a @_silgen_name(raw: ...) syntax, which simply avoids mangling the name (by using the \01 name prefix that LLVM uses). The motivation for that is to be able to reference the "magic Darwin linker symbols" that can be used to look up section bounds (in the current dylib/module) -- those symbols don't use the underscore prefix in their mangled names.
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.
This source location will be used to determine whether to add a name lookup
option to exclude macro expansions when the name lookup request is constructed.
Currently, the source location argument is unused.
The `hasStorage()` computation is used in many places to determine the
signatures of other declarations. It currently needs to expand accessor
macros, which causes a number of cyclic references. Provide a
simplified request to determine `hasStorage` without expanding or
resolving macros, breaking a common pattern of cycles when using
macros.
Fixes rdar://109668383.
This PR makes diagnostics on deserialization errors caused by project
configuration more helpful by providing contextual information on the
issue:
- Path to the modules involved (up to 4 modules): the loaded swiftmodule
with the broken outgoing reference, the path to the module where the
decl was expected, the path to the underlying clang module, and the path
to the module where the decl was found. This information should prevent
us from having to ask for a different log with `-Rmodule-loading`.
- Hint to delete the swiftmodule files when the module is
library-evolution enabled.
- Hint that clang settings affect clang modules involved in this
scenario.
- Pointing out when a decl moved between two modules with a similar name
(where one name is a prefix of the other). This is a common issue when
headers are shared between a clang framework's public and private
modules.
- Pointing out layering issues when an SDK module imports a local
module.
- Pointing out Swift language version mismatch which may lead to the
compiler viewing the same clang decls differently when they are modified
by APINotes files.
Use the `attempting forced recovery` diagnostic as main warning to which
we attach other messages as notes. Also mention the flag in the
diagnostic to reinforce that the flag is active.
Intro a deserialization mode controlled by the flag
`-experimental-force-workaround-broken-modules` to attempt unsafe
recovery from deserialization failures caused by project issues.
The one issue handled at this time is when a type moves from one module
to another. With this new mode the compiler may be able to pick a
matching type in a different module. This is risky to use, but may help
in a pinch for a client to fix and issue in a library over which they
have no control.
Deserialization recovery silently drops errors and the affected decls.
This can lead to surprises when a function from an imported module
simply disappears without an explanation.
This commit introduces the flag -Rmodule-recovery to report as remarks
some of these previously silently dropped issues. It can be used to
debug project configuration issues.
Intro the service `diagnoseAndConsumeError` as the ultimate site to drop
deserialization issues we can recover from. It will be used to raise
diagnostics on the issues before dropping them silently.
Move some deserialization error handling services to methods under ModuleFile.
This will give access to the ASTContext and allow to report diagnostics.
Also rename `consumeErrorIfXRefNonLoadedModule` into the more general
`consumeExpectedError` that is more appropriate for future improvements.
The Swift compiler expects the context to remain stable between when a
module is built and loaded by a client. Usually the build system would
rebuild a module if a dependency changes, or the compiler would rebuilt
the module from a swiftinterface on a context change. However, such
changes are not always detected and in that case the compiler may crash
on an inconsistency in the context. We often see this when a clang
module is poorly modularized, the headers are modified in the SDK, or
some clang define change its API.
These are project issues that used to make the compiler crash, it
provided a poor experience and doesn't encourage the developer to fix
them by themselves. Instead, let's keep track of modularization issues
encountered during deserialization and report them as proper errors when
they trigger a fatal failure preventing compilation.
Parse compound and special names in the macro role attributes
(`@freestanding` and `@attached`). This allows both compound names and
initializers, e.g., `init(coding:)`.
Fixes rdar://107967344.
When reading a swiftmodule that's part of the main module the compiler
should have access to all internal details. In that case, read the
underlying type to opaque types.
This was caught by `SILOptimizer/specialize_opaque_result_types2.sil`
which has a merge-module like behavior reading it sib files as input.
Clients of a resilient module using opaque types don't need access to
the underlying type unless it's used in an inlinable context. Plus, the
underlying type can reference internal details which can lead to crashes
when they reference implementation-only dependencies. To clean up this
behavior, let's only serialize the underlying type if used by an
inlinable function.
rdar://105128784
