Decrease the size of nominal type descriptors and make them true-const by relative-addressing the other metadata they need to reference, which should all be included in the same image as the descriptor itself. Relative-referencing string constants exposes a bug in the Apple linker, which crashes when resolving relative relocations to coalesceable symbols (rdar://problem/22674524); work around this for now by revoking the `unnamed_addr`-ness of string constants that we take relative references to. (I haven't tested whether GNU ld or gold also have this problem on Linux; it may be possible to conditionalize the workaround to only apply to Darwin targets for now.)
If a struct has fixed layout but contains fields which are opaque,
or if the struct itself is opaque, use a metadata accessor function
instead of loading the metadata directly.
Let's say that A and B are two structs defined in the same module,
and B has a fixed size. This patch adds support for these two cases:
1) Fixed-layout struct A contains resilient struct B
2) Resilient struct A contains resilient struct B
In case 1),
a) Inside X: A is fixed-size and has constant metadata
i) Direct metadata access can be performed on A and B
ii) Direct field access can be performed on A and B
d) Outside X: B has an opaque layout
i) Metadata accessor must be called for A and B
ii) Fields of A do not have constant offsets, instead the offsets
must be loaded from type metadata
Case 2) is the same as above except ii) does not apply, since fields
of resilient structs are manipulated via accessors.
Eventually, we will use metadata accessor functions for all public
struct and enum types.
John and I discussed this and agreed that we only need two cases here,
not four. In the future this may be merged with ResilienceExpansion,
and become a struct with additional availability information, but
we're definitely sure we don't need four levels here.
Add a new ResilientStructTypeInfo. This is a singleton since
all resilient structs have opaque payloads and are accessed
through value witness tables.
With this in place, flesh out IRGenModule::isResilient() and
use the new singleton to convert resilient structs.
Note that the old isResilient() was hard-coded to report that
all Clang-imported classes are "resilient". Now that this has
been unified with NominalTypeDecl::hasFixedLayout(), we will
report Clang-imported classes are "resilient" at the SIL level.
This should not introduce any semantic differences at this
point.
Unlike SIL, where currently resilient types are always resilient
even when used from the same module, IRGen is able to perform
direct manipulation of resilient structs from the current
module, since IRGen's type lowering has a resilience scope
plumbed through.
Note that we do not yet support laying out structs and classes
containing resilient fields -- this will come in a future patch.
IRGen emits lazily-emitted definitions after emitting Clang declarations.
So an internal function that references an Objective-C class global and
is itself referenced from after a public function can observe
a OBJC_CLASS_$_ global defined by Clang.
Use a similar strategy as the Clang patch, just bitcast the global if it
exists already.
Fixes <rdar://problem/23200656>.
Swift SVN r32845
- GenProto.cpp for protocols and protocol conformances
- GenExistential.cpp for existential type layout and operations
- GenArchetype.cpp for archetype type layout and operations
Swift SVN r32493
The new implementation needs to happen after all source files have been built and before lazy definitions are emitted, but I neglected to insert it in the parallel IRGen path. Fixes rdar://problem/22825770.
Swift SVN r32189
NFC, but this set of access modes applies more generally to other kinds of metadata that may need to be guarded by accessors, such as witness tables.
Swift SVN r31838
By using relative references, either directly to symbols internal to the current TU, or to the GOT entry for external symbols, we avoid unnecessary runtime relocations, and we save space on 64-bit platforms, since a single image is still <2GB in size. For the 64-bit standard library, this trades 26KB of fake-const data in __DATA,__swift1_proto for 13KB of true-const data in __TEXT,__swift2_proto. Implements rdar://problem/22334380.
Swift SVN r31555
This is more resilient, since we want to be able to add more information behind the address point of type objects. The start of the metadata object is now an internal "full metadata" symbol.
Note that we can't do this for known opaque metadata from the C++ runtime, since clang doesn't have a good way to emit offset symbol aliases, so for non-nominal metadata objects we still emit an adjustment inline. We also aren't able to generate references to aliases within the same module due to an MC bug with alias refs on i386 and armv7 (rdar://problem/22450593).
Swift SVN r31523
This is more resilient, since we want to be able to add more information behind the address point of type objects, and also makes IR a lot less cluttered. The start of the metadata object is now an internal "full metadata" symbol.
Note that we can't do this for known opaque metadata from the C++ runtime, since clang doesn't have a good way to emit offset symbol aliases, so for non-nominal metadata objects we still emit an adjustment inline.
Swift SVN r31515
Core Data synthesizes Key-Value-Coding-compliant accessors for @NSManaged
properties, but Swift won't allow them to be called without predeclaring
them.
In practice, '@NSManaged' on a method is the same as 'dynamic', except
you /can't/ provide a body and overriding it won't work. This is not the
long-term model we want (see rdar://problem/20829214), but it fixes a
short-term issue with an unfortunate workaround (go through
mutableOrderedSetValueForKey(_:) and similar methods).
rdar://problem/17583057
Swift SVN r30523
Generic subclasses of @objc classes are thus no longer @objc, but still
have implicitly @objc members.
Explicit @objc on generic classes or classes that inherit from @objc
classes is now forbidden with a diagnostic. Users need to know that
while they can override Objective-C methods and properties in such
a class, they cannot refer to the class by name from Objective-C code,
since it will not appear in the bridging header.
Fixes <rdar://problem/21342574>.
Swift SVN r30494
The FIXME comment no longer applied and the if statement didn't make
sense. Perhaps the 'break' was at one point meant to be a 'continue',
however now we seem to correctly handle emission of a property
descriptor for a property without accessors.
Fixes <rdar://problem/21474718>.
Swift SVN r30132
The isDependentType() query is woefully misunderstood. Some places
seem to want it to mean "a generic type parameter of dependent member
type", which corresponds to what is effectively a type parameter in
the language, while others want it to mean "contains a type parameter
anywhere in the type". Tease out these two meanings in
isTypeParameter() and hasTypeParameter(), respectively, and sort out
the callers.
Swift SVN r29945
This comes up when the SIL global actually refers to a static global defined
in C. In these cases Clang may have already emitted the global with a
different type---one appropriate for Clang, but not for Swift. By the time
we get to this part of the code, we should have already rejected anything not
layout-compatible, so just do the bitcast and be done with it.
Reviewed by John.
rdar://problem/21361469
Swift SVN r29471
The test that it's guarding is cheap enough to do all the time, and we
don't have any interesting configurations where it's not set any more.
Swift SVN r29442
We need this because that global state includes tables like llvm[.compiler].used
which would otherwise be sorely missed.
This fixes an issue of the clang importer that would cause us to fail whenever
we imported a function (say it is marked as static inline) that performs an
objective-c method call and we optimize the code. The optimizer would not see
the objective-c selector global variable (which is marked private) as being
"used by unkown i.e the objc runtime" and would rightly assume it could
propagate the value of the global variable's initializer value as a constant to
loads of the global variable.
Now we call the ClangCodeGenerators translation unit finalization code which
will emit these tables and other module flags. We need to take care that we
merge those datastrutures with datastructures that we emit from swift's IRGen.
rdar://21115194
Swift SVN r29176
Modules occupy a weird space in the AST now: they can be treated like
types (Swift.Int), which is captured by ModuleType. They can be
treated like values for disambiguation (Swift.print), which is
captured by ModuleExpr. And we jump through hoops in various places to
store "either a module or a decl".
Start cleaning this up by transforming Module into ModuleDecl, a
TypeDecl that's implicitly created to describe a module. Subsequent
changes will start folding away the special cases (ModuleExpr ->
DeclRefExpr, name lookup results stop having a separate Module case,
etc.).
Note that the Module -> ModuleDecl typedef is there to limit the
changes needed. Much of this patch is actually dealing with the fact
that Module used to have Ctx and Name public members that now need to
be accessed via getASTContext() and getName(), respectively.
Swift SVN r28284
All llvm::Functions created during IRGen will have target-cpu and target-features
attributes if they are non-null.
Update testing cases to expect the attribute in function definition.
Add testing case function-target-features.swift to verify target-cpu and
target-features.
rdar://20772331
Swift SVN r28186
Instead of putting a function without an associated source-file into the primary module,
it is now put into the module which first references the function.
Swift SVN r28116
and link it properly. This is needed to embed LLVM bitcode sections
in the standard library and overlays. The linker doesn't support
embedded bitcode and reexport flags (among others).
rdar://problem/20750099
Swift SVN r28052