The main point of this change is to make sure that a shared function always has a body: both, in the optimizer pipeline and in the swiftmodule file.
This is important because the compiler always needs to emit code for a shared function. Shared functions cannot be referenced from outside the module.
In several corner cases we missed to maintain this invariant which resulted in unresolved-symbol linker errors.
As side-effect of this change we can drop the shared_external SIL linkage and the IsSerializable flag, which simplifies the serialization and linkage concept.
ABI descriptors should always be emitted as sidecars for library-evolution-enabled modules.
However, generating these files requires traversing the entire module (like indexing), which may
hit additional deserialization issues. To unblock builds, this patch introduces a flag to skip
the traversing logic so that we emit an empty ABI descriptor file. The empty file serves as
a placeholder so that build system doesn't need to know the details.
When looking for a Swift module on disk, we were scanning all module search paths if they contain the module we are searching for. In a setup where each module is contained in its own framework search path, this scaled quadratically with the number of modules being imported. E.g. a setup with 100 modules being imported form 100 module search paths could cause on the order of 10,000 checks of `FileSystem::exists`. While these checks are fairly fast (~10µs), they add up to ~100ms.
To improve this, perform a first scan of all module search paths and list the files they contain. From this, create a lookup map that maps filenames to the search paths they can be found in. E.g. for
```
searchPath1/
Module1.framework
searchPath2/
Module1.framework
Module2.swiftmodule
```
we create the following lookup table
```
Module1.framework -> [searchPath1, searchPath2]
Module2.swiftmodule -> [searchPath2]
```
We noticed some Swift clients rely on the serialized search paths in the module to
find dependencies and droping these paths altogether can lead to build failures like
rdar://85840921.
This change teaches the serialization to obfuscate the search paths and the deserialization
to recover them. This allows clients to keep accessing these paths without exposing
them when shipping the module to other users.
We've recently added the -experimental-hermetic-seal-at-link compiler flag,
which turns on aggressive dead-stripping optimizations and assumes that library
code can be optimized against client code because all users of the library
code/types are present at link/LTO time. This means that any module that's
built with -experimental-hermetic-seal-at-link requires all clients of this
module to also use -experimental-hermetic-seal-at-link. This PR enforces that
by storing a bit in the serialized module, and checking the bit when importing
modules.
This commit adds a new frontend flag that applies debug path prefixing to the
paths serialized in swiftmodule files. This makes it possible to use swiftmodule
files that have been built on different machines by applying the inverse map
when debugging, in a similar fashion to source path prefixing.
The inverse mapping in LLDB will be handled in a follow up PR.
Second pass at #39138
Tests updated to handle windows path separators.
This reverts commit f5aa95b381.
* Fix unnecessary one-time recompile of stdlib with -enable-ossa-flag
This includes a bit in the module format to represent if the module was
compiled with -enable-ossa-modules flag. When compiling a client module
with -enable-ossa-modules flag, all dependent modules are checked for this bit,
if not on, recompilation is triggered with -enable-ossa-modules.
* Updated tests
This commit adds the `-prefix-serialized-debugging-options` flag,
which is used to apply the debug prefix map to serialized debugging
options embedded in the swiftmodule files.
Introduce a new loading restriction that is more strict than the serialization
version check on swiftmodules. Tagged compilers will only load
library-evolution enabled swiftmodules that are produced by a compiler with the
exact same revision id. This will be more reliable in production
environments than using the serialization version which we forgot to
update from time to time. This shouldn't affect development compilers that
will still load any module with a compatible serialization version.
rdar://83105234
Serialize the canonical name of the SDK used when building a swiftmodule
file and use it to ensure that the swiftmodule file is loaded only with
the same SDK. The SDK name must be passed down from the frontend.
This will report unsupported configurations like:
- Installing roots between incompatible SDKs without deleting the
swiftmodule files.
- Having multiple targets in the same project using different SDKs.
- Loading a swiftmodule created with a newer SDK (and stdlib) with an
older SDK.
All of these lead to hard to investigate deserialization failures and
this change should detect them early, before reaching a deserialization
failure.
rdar://78048939
We should hold off actually building the binary module file until it is imported.
`canImport` queries can happen, for example, during dependency scanning, when we do not wish to have the scanner tool execute any module builds.
Resolves rdar://82603098
The MemoryBuffer loader is used by LLDB during debugging to import binary Swift
modules from .swift_ast sections. Modules imported from .swift_ast sections are
never produced from textual interfaces. By disabling resilience the expression
evaluator in the debugger can directly access private members.
rdar://79462915
Rework Sendable checking to be completely based on "missing"
conformances, so that we can individually diagnose missing Sendable
conformances based on both the module in which the conformance check
happened as well as where the type was declared. The basic rules here
are to only diagnose if either the module where the non-Sendable type
was declared or the module where it was checked was compiled with a
mode that consistently diagnoses `Sendable`, either by virtue of
being Swift 6 or because `-warn-concurrency` was provided on the
command line. And have that diagnostic be an error in Swift 6 or
warning in Swift 5.x.
There is much tuning to be done here.
It's a known issue that we are using arm64e interfaces contents for the arm64 target,
meaning the encoded module flags are specifying -target arm64e-x-x instead of
-target arm64-x-x. Fortunately, we can tell the target arch from the interface file
name, so we could sanitize the target to use by inferring arch from the file name.
Foundation imports CoreFoundation with `@_implementationOnly`,
so CoreFoundation's modulemap won't be read, and the dependent libraries
of CoreFoundation will not be automatically linked when using static
linking.
For example, CoreFoundation depends on libicui18n and it's modulemap has
`link "icui18n"` statement. If Foundation imports CoreFoundation with
`@_implementationOnly` as a private dependency, the toolchain doesn't have
CoreFoundation's modulemap and Foundation's swiftmodule doesn't import
CoreFoundation. So the swiftc can't know that libicui18n is required.
This new option will add LINK_LIBRARY entry in swiftmodule to
specify dependent libraries (in the example case, Foundation's
swiftmodule should have LINK_LIBRARY entry of libicui18n)
See also: [Autolinking behavior of @_implementationOnly with static linking](https://forums.swift.org/t/autolinking-behavior-of-implementationonly-with-static-linking/44393)
This mechanism allows the compiler to use a backup interface file to build into a binary module when
a corresponding interface file from the SDK is failing for whatever reasons. This mechansim should be entirely opaque
to end users except several diagnostic messages communicating backup interfaces are used.
Part of rdar://77676064
For config condition `canImport(Foo, version: N)`, this patch teaches the compiler to check N
against the version of the Swift module Foo on disk. It returns true if the module version on
disk is greater or equal to N and returns false otherwise.
Part of rdar://73992299
canImport should be able to take an additional parameter labeled by either version or
underlyingVersion. We need underlyingVersion for clang modules with Swift overlays because they
have separate version numbers. The library users are usually interested in checking the importability
of the underlying clang module instead of its Swift overlay.
Part of rdar://73992299
If the `-static` option is specified, store that in the generated
swiftmodule file. When de-serializing, recover this information in the
representative SILModule.
This will be used for code generation on Windows. It is the missing
piece to allow static linking to function properly. It additionally
opens the path to additional optimization on ELF-ish targets - GOT, PLT
references can be avoided when the linked module is known to be static.
Co-authored by: Saleem Abdulrasool <compnerd@compnerd.org>
This allows library authors to pass down a project version number so that library users can conditionally
import that library based on the available version in the search paths.
Needed for rdar://73992299
The locations stored in .swiftsourceinfo included the presumed file,
line, and column. When a location is requested it would read these, open
the external file, create a line map, and find the offset corresponding
to that line/column.
The offset is known during serialization though, so output it as well to
avoid having to read the file and generate the line map.
Since the serialized location is returned from `Decl::getLoc()`, it
should not be the presumed location. Instead, also output the line
directives so that the presumed location can be built as per normal
locations.
Finally, move the cache out of `Decl` and into `ASTContext`, since very
few declarations will actually have their locations deserialized. Make
sure to actually write to that cache so it's used - the old cache was
never written to.
Cursor info for a constructor would previously give the cursor info for
the containing type only. It now also adds cursor info for the
constructor itself in a "secondary_symbols" field.
Refactor `passCursorInfoForDecl` to use a single allocator rather than
keeping track of positions in a buffer and assigning everything at the
end of the function.
Refactor the various available refactoring gathering functions to take a
SmallVectorImpl and to not copy strings where they don't need to.
Resolves rdar://75385556
Introduce a new compiler flag `-module-abi-name <name>` that uses the
given name as the ABI name for the module (rather than the module's
name in source code). The ABI name impacts name mangling and metadata.
In the legacy driver, these flags will merely be propagated to the
frontends to indicate that they should disable serialization of
incremental information in swift module files.
In the new driver, these flags control whether the Swift driver performs
an incremental build that is aware of metadata embedded in the module.
Kudos to David for coming up with our new marketing name: Incremental
Imports.
rdar://74363450
Otherwise, one runs into memory corruption. I ran into this while enabling ossa
on the stdlib for non-Darwin platforms.
Hopefully we do not regress on this again when someone adds more optzns that
eliminate these since I added a big NOTE to warn people to do it and implemented
support even for the entities we do not support deleting at the SIL
level... yet.
Adds a new frontend option
"-experimental-allow-module-with-compiler-errors". If any compilation
errors occur while generating the .swiftmodule, this mode will skip SIL
entirely and only serialize the (likey invalid) AST.
This existence of this option during generation is serialized into the
resulting .swiftmodule. Errors found in deserialization are only allowed
if it is set.
Primarily intended for IDE requests (eg. indexing and code completion)
to ensure robust cross-module results, despite possible errors.
Resolves rdar://69815975
