SIL type lowering erases DynamicSelfType, so we generate
incorrect code when casting to DynamicSelfType. Fixing this
requires a fair amount of plumbing, but most of the
changes are mechanical.
Note that the textual SIL syntax for casts has changed
slightly; the target type is now a formal type without a '$',
not a SIL type.
Also, the unconditional_checked_cast_value and
checked_cast_value_br instructions now take the _source_
formal type as well, just like the *_addr forms they are
intended to replace.
Now that we're never relatively addressing an Objective-C class reference,
stop emitting them as file-local (by eliminating the \01l_ prefix). This
is both a minor optimization and also a way to ensure that things will
break more consistently if a problem remains.
Currently ignored, but this will allow future compilers to pass down source location information for cast
failure runtime errors without backward deployment constraints.
Reimplement protocol descriptors for Swift protocols as a kind of
context descriptor, dropping the Objective-C protocol compatibility
layout. The new protocol descriptors have several advantages over the
current implementation:
* They drop all of the unused fields required for layout-compatibility
with Objective-C protocols.
* They encode the full requirement signature of the protocol. This
maintains more information about the protocol itself, including
(e.g.) correctly encoding superclass requirements.
* They fit within the general scheme of context descriptors, rather than
being their own thing, which allows us to share more code with
nominal type descriptors.
* They only use relative pointers, so they’re smaller and can be placed
in read-only memory
Implements rdar://problem/38815359.
Within conformance records, reference Objective-C class objects
indirectly so the runtime can update those references appropriately.
We don't need to do this for classes with Swift metadata.
Make all OBJC_CLASS_REF symbols object-local using "\01l", which
prevents the linker from producing incorrect relative addresses.
Fixes the ABI-affecting part of rdar://problem/36310179.
* Remove RegisterPreservingCC. It was unused.
* Remove DefaultCC from the runtime. The distinction between C_CC and DefaultCC
was unused and inconsistently applied. Separate C_CC and DefaultCC are
still present in the compiler.
* Remove function pointer indirection from runtime functions except those
that are used by Instruments. The remaining Instruments interface is
expected to change later due to function pointer liability.
* Remove swift_rt_ wrappers. Function pointers are an ABI liability that we
don't want, and there are better ways to get nonlazy binding if we need it.
The fully custom wrappers were only needed for RegisterPreservingCC and
for optimizing the Instruments function pointers.
Use the generic type lowering algorithm described in
"docs/CallingConvention.rst#physical-lowering" to map from IRGen's explosion
type to the type expected by the ABI.
Change IRGen to use the swift calling convention (swiftcc) for native swift
functions.
Use the 'swiftself' attribute on self parameters and for closures contexts.
Use the 'swifterror' parameter for swift error parameters.
Change functions in the runtime that are called as native swift functions to use
the swift calling convention.
rdar://19978563
Swift uses rt_swift_* functions to call the Swift runtime without using dyld's stubs. These functions are renamed to swift_rt_* to reduce namespace pollution.
rdar://28706212
Till now, a SIL module would be only verified if an optimization has changed it. But if there were no changes, then no verification would happen and some SIL module format errors would stay unnoticed. This was happening in certain cases when reading a textual SIL module representation, which turned out to be broken, but SIL verifier wouldn't catch it.
Swift SVN r31863
To invoke the front-end on a SIL with whole-module optimizations enabled, execute:
swiftc -frontend myfile.sil
To invoke the front-end on a SIL without whole-module optimizations enabled, add a -primary-file option:
swiftc -frontend -primary-file myfile.sil
To invoke a sil-opt with whole-module optimizations enabled, use the -wmo option:
sil-opt myfile.sil -wmo
This change was need to be able to write SIL unit tests which should be compiled in the WMO mode.
Swift SVN r31862
And they're not even guaranteed to be casts to ObjC classes. They might be
Swift subclasses of ObjC classes.
This fixes a type-safety hole where, e.g. a generic cast from NSPredicate
to NSDate was allowed because we were checking against NSObject.
rdar://problem/22242369
Swift SVN r31153