initialization in-place on demand. Initialize parent metadata
references correctly on struct and enum metadata.
Also includes several minor improvements related to relative
pointers that I was using before deciding to simply switch the
parent reference to an absolute reference to get better access
patterns.
Includes a fix since the earlier commit to make enum metadata
writable if they have an unfilled payload size. This didn't show
up on Darwin because "constant" is currently unenforced there in
global data containing relocations.
This patch requires an associated LLDB change which is being
submitted in parallel.
initialization in-place on demand. Initialize parent metadata
references correctly on struct and enum metadata.
Also includes several minor improvements related to relative
pointers that I was using before deciding to simply switch the
parent reference to an absolute reference to get better access
patterns.
This reorganization allows adding attributes that refer to types.
I need this for a @_specialize attribute with a type list.
PrintOptions.h and other headers depend on these enums. But Attr.h
defines a lot of classes that almost never need to be included.
Similarly to how we've always handled parameter types, we
now recursively expand tuples in result types and separately
determine a result convention for each result.
The most important code-generation change here is that
indirect results are now returned separately from each
other and from any direct results. It is generally far
better, when receiving an indirect result, to receive it
as an independent result; the caller is much more likely
to be able to directly receive the result in the address
they want to initialize, rather than having to receive it
in temporary memory and then copy parts of it into the
target.
The most important conceptual change here that clients and
producers of SIL must be aware of is the new distinction
between a SILFunctionType's *parameters* and its *argument
list*. The former is just the formal parameters, derived
purely from the parameter types of the original function;
indirect results are no longer in this list. The latter
includes the indirect result arguments; as always, all
the indirect results strictly precede the parameters.
Apply instructions and entry block arguments follow the
argument list, not the parameter list.
A relatively minor change is that there can now be multiple
direct results, each with its own result convention.
This is a minor change because I've chosen to leave
return instructions as taking a single operand and
apply instructions as producing a single result; when
the type describes multiple results, they are implicitly
bound up in a tuple. It might make sense to split these
up and allow e.g. return instructions to take a list
of operands; however, it's not clear what to do on the
caller side, and this would be a major change that can
be separated out from this already over-large patch.
Unsurprisingly, the most invasive changes here are in
SILGen; this requires substantial reworking of both call
emission and reabstraction. It also proved important
to switch several SILGen operations over to work with
RValue instead of ManagedValue, since otherwise they
would be forced to spuriously "implode" buffers.
- Implement emission of type references for nominal type field
reflection, using a small custom encoder resulting in packed
structs, not strings. This will let us embed 7-bit encoded
32-bit relative offsets directly in the structure (not yet
hooked in).
- Use the AST Mangler for encoding type references
Archetypes and internal references were complicating this before, so we
can take the opportunity to reuse this machinery and avoid unique code
and new ABI.
Next up: Tests for reading the reflection sections and converting the
demangle tree into a tree of type references.
Todo: For concrete types, serialize the types for associated types of
their conformances to bootstrap the typeref substitution process.
rdar://problem/15617914
In a few places, we have to be careful about the distinction between
"empty in this resilience domain" versus "empty in all resilience
domains". Make callers think about this by adding a parameter instead
of relying on them to check isFixedSize() as necessary first.
While making this change I noticed that the code for checking if
types are empty when computing extra inhabitants of structs and enums
might be slightly wrong in the face of resilience; I will revisit
this later.
Now that all the machinery is in place, the ClassMetadataBuilder
can (more accurately) query the ClassLayout instead of trying to
re-derive whether the field offset vector is dependent, etc.
Apart from performing dynamic layout for resiliently-sized fields
in concrete classes, this also lets us *skip* dynamic layout
if we have a generic class without any dependent fields.
I haven't tested subclassing with resilient field layout yet, but
getting that working is the next step and should not be too much
work.
Also, swift_initClassMetadata_UniversalStrategy() only stores
the computed field offsets in the field offset globals when the
Objective-C runtime is available, because it gets the offset
pointers from the Objective-C class rodata. On Linux, we will
need to emit code to copy from the field offset vector into
field offset globals in IRGen. This is pretty easy, but I'll do
it in a follow-up patch so for now the new execution test is
XFAIL'd on Linux.
We don't actually care that the field offset is fixed in the
struct layout, only that it is not dependent.
This is NFC for now, until resilient class layout lands.
ClassLayoutBuilder computes a bunch of stuff in addition to the
StructLayout, which is then stashed in ClassTypeInfo. Extract this
into a new ClassLayout type. It probably should not exist at all,
if we only generalized StructLayout a bit.
This tells us if the superclass field offsets are non-constant,
in which case they have to be copied in.
This will be used to simplify some code and plug in value type
resilience.
Subclasses of imported Objective-C classes have an unknown size, but
the start of the class's fields in the field offset vector is fixed,
since the field offset vector only contains offsets of Swift stored
properties. So we can always access fields with NonConstantDirect
(for concrete) or ConstantIndirect (for generic types).
On the other hand, generic subclasses of resilient classes must use
the most general NonConstantIndirect access pattern, because we can
add new fields resiliently.
Also, assume NSObject won't change size or grow any new instance
variables, allowing us to use the ConstantDirect access pattern.
This is a bit of a hodge-podge of related changes that I decided
weren't quite worth teasing apart:
First, rename the weak{Retain,Release} entrypoints to
unowned{Retain,Release} to better reflect their actual use
from generated code.
Second, standardize the names of the rest of the entrypoints around
unowned{operation}.
Third, standardize IRGen's internal naming scheme and API for
reference-counting so that (1) there are generic functions for
emitting operations using a given reference-counting style and
(2) all operations explicitly call out the kind and style of
reference counting.
Finally, implement a number of new entrypoints for unknown unowned
reference-counting. These entrypoints use a completely different
and incompatible scheme for working with ObjC references. The
primary difference is that the new scheme abandons the flawed idea
(which I take responsibility for) that we can simulate an unowned
reference count for ObjC references, and instead moves towards an
address-only scheme when the reference might store an ObjC reference.
(The current implementation is still trivially takable, but that is
not something we should be relying on.) These will be tested in a
follow-up commit. For now, we still rely on the bad assumption of
reference-countability.
The predicate for evaluating if a nominal type has constant metadata was
repeated in a few places, factor it out. Also, the generic signature was
passed down to GenericMetadataBuilderBase, but its not actually used there,
so remove it.
The classifyTypeSize() method was duplicating work done by IRGen's
type lowering, and it was slightly wrong in a few cases. After the
class archetype spare bits cleanup, the only remaining usage of this
method is in class layout. Just use TypeInfo instead.
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.
The swift_unknown* entry points are not available on the Linux port.
Previously we would still attempt to use them in a couple of cases:
1) Foreign classes
2) Existentials and archetypes
3) Optionals of boxed existentials
Note that this patch changes IRGen to never emit the
swift_errorRelease/Retain entry points on Linux. We would like to
use them in the future if we ever adopt a tagged-pointer representation
for small errors. In this case, they can be brought back, and the
TypeInfo for optionals will need to be generalized to propagate the
reference counting of the payload type, instead of defaulting to
unknown if the payload type is not natively reference counted.
A similar change will need to be made to support blocks, if we ever
want to use the blocks runtime on Linux.
Fixes <rdar://problem/23335318>, <rdar://problem/23335537>,
<rdar://problem/23335453>.
This means: handling of alloc_ref [stack].
It can be configured with two new options. See Option/FrontendOptions.td.
As the [stack] attribute is not generated yet, there should be NFC.
Swift SVN r32929
dealloc_ref [destructor] is the existing behavior. It expects the
reference count to have reached zero and the isDeallocating bit to
be set.
The new [constructor] variant first drops the initial strong
reference.
This allows DI to properly free uninitialized instances in
constructors. Previously this would fail with an assertion if the
runtime was built with debugging enabled.
Progress on <rdar://problem/21991742>.
Swift SVN r31142
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
SILFunctionType of the method instead of its formal type.
Gives more accurate information to the @encoding, makes
foreign error conventions work implicitly, and allows
IRGen's Swift-to-Clang to avoid duplicating arbitrary
amounts of the bridging logic from SILGen.
Some finagling was required in order to avoid calling
getConstantFunctionType from within other kinds of
lowering, which might have re-entered a generic context.
Also required fixing a bug with the type lowering of
optional DynamicSelfTypes where we would end up with
a substituted type in the lowered type.
Also, for some reason, our @encoding for -dealloc
methods was pretending that there was a formal parameter.
There didn't seem to be any justification for this,
and it's not like Clang does that. Fixed.
This commit reapplies r29266 with a conservative build fix
that disables ObjC property descriptors for @objc properties
that lack a getter. That should only be possible in SIL
files, because @objc should force accessors to be synthesized.
Arguably, Sema shouldn't be marking things implicitly @objc
in SIL files, but I'll leave that decision open for now.
Swift SVN r29272
SILFunctionType of the method instead of its formal type.
Gives more accurate information to the @encoding, makes
foreign error conventions work implicitly, and allows
IRGen's Swift-to-Clang to avoid duplicating arbitrary
amounts of the bridging logic from SILGen.
Some finagling was required in order to avoid calling
getConstantFunctionType from within other kinds of
lowering, which might have re-entered a generic context.
Also required fixing a bug with the type lowering of
optional DynamicSelfTypes where we would end up with
a substituted type in the lowered type.
Also, for some reason, our @encoding for -dealloc
methods was pretending that there was a formal parameter.
There didn't seem to be any justification for this,
and it's not like Clang does that. Fixed.
Swift SVN r29266
The last remaining case was apparently @objc generic classes, which
seem to work now.
Also nuke the IRGen/unimplemented_objc_generic_class.swift test,
this is now implemented and we have other tests that test this
functionality.
Swift SVN r29260
It looks like John and Joe already did a good part of this. The previous
patch to enable polymorphic @objc_method signatures takes us further, and
I think this patch fills in the rest.
Fixes <rdar://problem/18505295>, <rdar://problem/20700287>.
Swift SVN r29259
The last remaining case was apparently @objc generic classes, which
seem to work now.
Also nuke the IRGen/unimplemented_objc_generic_class.swift test,
this is now implemented and we have other tests that test this
functionality.
Swift SVN r29138
It looks like John and Joe already did a good part of this. The previous
patch to enable polymorphic @objc_method signatures takes us further, and
I think this patch fills in the rest.
Fixes <rdar://problem/18505295>, <rdar://problem/20700287>.
Swift SVN r29137
