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.
If a value is returned as @owned, we can move the epilogue retain
to the caller and convert the return value to @unowned. This gives
ARC optimizer more freedom to optimize the retain out on the caller's
side.
It appears that epilgue retains are harder to find than epilogue
releases. Most of the time they are not in the return block.
(1) Sometimes, they are in predecessors
(2) Sometimes they come from a call which returns an @owned return value.
This should be improved if we fix (1) and go bottom up.
(3) We do not handle exploded retain_value.
Currently, this catches a small number of opportunities.
We probably need to improve epilogue retain matcher if we are to handle
more cases.
This is part of rdar://24022375.
We also need some refactoring in the pass. e.g. break functions into smaller
functions. I will do with subsequent commit.
The main idea here is that we really, really want to be
able to recover the protocol requirement of a conformance
reference even if it's abstract due to the conforming type
being abstract (e.g. an archetype). I've made the conversion
from ProtocolConformance* explicit to discourage casual
contamination of the Ref with a null value.
As part of this change, always make conformance arrays in
Substitutions fully parallel to the requirements, as opposed
to occasionally being empty when the conformances are abstract.
As another part of this, I've tried to proactively fix
prospective bugs with partially-concrete conformances, which I
believe can happen with concretely-bound archetypes.
In addition to just giving us stronger invariants, this is
progress towards the removal of the archetype from Substitution.
This commit is related to the work of encoding mangled names more efficiently by
compressing them. This commit adds two new methods to the mangler that allows it
to identify requests to mangle strings that are already mangled. Right now the
mangler does not do anything with this information.
This API is needed in all of the places in the compiler where we compose mangled
names. For example, when the optimizer is cloning functions it adds a prefix to
an existing name.
I verified that this change is correct by adding a compress/decompress methods
that add a prefix to the mangled names with assertions to catch compression of
already compressed symbols or decompression of non-compressed named. I plan to
commit the verification code together with the compression implementation later
on.
Match the new SILGen pattern, where only the box parameter is partially applied to the closure, and the address of the value is projected on the callee side.
This enables dead argument elimination to be paired with @owned -> @guaranteed
optimization. It has the additional advantage of allowing us to potentially
eliminate additional retains, releases since the fact that the use is dead
implies that the lifetime of the value no longer needs to be live across the
function call.
Since dead argument elimination can be composed with @owned -> @guaranteed, I
had to modify the mangler, remangler, demangler, to be able to handle a mangling
that combines the two.
I just saw noise in the perf test suite.
rdar://21114206
Swift SVN r29966
I am starting to reuse manglings for different passes. I want to make sure that
when we reuse functions we actually get a function created by the same pass.
Swift SVN r23924
Now all SIL function specialization passes use the new mangling infrastructure.
Lets keep it that way for future passes as well. = ).
Implements:
<rdar://problem/18831609>
Fixes:
<rdar://problem/19065735>
<rdar://problem/18906781>
<rdar://problem/18956916>
Swift SVN r23859
This is apart of creating the infrastructure for creating special manglings for
all of the passes that we specialize. The main motiviations for this
infrastructure is:
1. Create an easy method with examples on how to create these manglings.
2. Support multiple specializations. This is important once we allow for partial
specialization and can already occur if we perform function signature
optimizations on specialized functions.
The overall scheme is as follows:
_TTS<MANGLINGINFO>__<FUNCNAME>
Thus if we specialize twice, the first specialization will just be treated as
the function name for the second specialization.
<MANGLINGINFO> is defined as:
_<SPECIALIZATIONKINDID>_<SPECIALIZATIONUNIQUEINFO>
Where specialization kind is an enum that specifies the specific sort of
specialization we are performing and specialization unique info is enough
information to ensure that the identity of the function is appropriately
preserved.
Swift SVN r23801
and remove DeclContext base class from FuncDecl, ConstructorDecl and
DestructorDecl
This decreases the number of DeclContexts to 7 and allows us to apply
alignas(8) to DeclContext.
Swift SVN r8186
Use the ordinal archetype manglings only for the primary archetypes of a generic context, and define a mangling for associated types relative to their parent archetype. This will make the archetype mangling resilient in the face of our planned improvements to associated type and protocol conformance ABI. It also correctly mangles self and associated types of protocols, which my previous attempt utterly failed to accomplish.
Swift SVN r8174
This should allow declarations inside protocols to mangle successfully, which is needed by SourceKit to be able to use mangled names as unique decl identifiers. I'm also planning to use mangled protocol decls to name generic curry thunk symbols.
This only introduces a mangling for independent associated types. I think we will eventually want to mangle dependent associated types (such as T.AssocType for an archetype T : SomeProtocol) with a non-indexed mangling too, but this doesn't do that yet.
Swift SVN r8148
This breaks the type-canonicalization link between a generic parameter
type and the archetype to which it maps. Generic type parameter types
are now separate entities (that can eventually be canonicalized) from
archetypes (rather than just being sugar).
Most of the front end still traffics in archetypes. As a step away
from this, allow us to type-check the generic parameter list's types
prior to wiring the generic type parameter declarations to archetypes,
using the new "dependent" member type to describe assocaited
types. The archetype builder understands dependent member types and
uses them to map down to associated types when building archetypes.
Once we have assigned archetypes, we revert the dependent identifier
types within the generic parameter list to an un-type-checked state
and do the type checking again in the presence of archetypes, so that
nothing beyond the generic-parameter-list checking code has to deal
with dependent types. We'll creep support out to other dependent types
elsewhere over time.
Swift SVN r7462
Another baby step toward a proper canonical form for polymorphic
function types: generic parameters will eventually be uniquable by
their depth and index.
Swift SVN r7380
The current implementation of dealloc_stack in IR-gen is a
no-op, but that's very much wrong for types with non-trivial
local allocation requirements, e.g. archetypes. So we need
to be able to do non-trivial code here. However, that means
modeling both the buffer pointer and the allocated address
in SIL.
To make this more type-safe, introduce a SIL-specific
'[local_storage] T' type that represents the required
allocation for locally storing a T. alloc_stack now returns
one of those in additon to a *T, and dealloc_stack expects
the former.
IR-gen still implements dealloc_stack as a no-op, but
that's now easy to fix.
Swift SVN r6937
We need to handle three cases:
- If a protocol conformance has no associated types, or the associated type witnesses all have statically resolvable metadata, we can expose a *direct* witness table symbol.
- If a protocol conformance has associated types with runtime-instantiated metadata, we need to gate the witness table behind a *lazy* initializer function to fill in the metadata fields.
- If a protocol conformance has associated types where the type or one of its conformances are *dependent* on its parent's generic parameters, we need to instantiate multiple witness tables at runtime.
Swift SVN r6805
We haven't fully updated references to union cases, and enums still are not
their own thing yet, but "oneof" is gone. Long live "union"!
Swift SVN r6783
This makes it very clear who is depending on special behavior at the
module level. Doing isa<ClangModule> now requires a header import; anything
more requires actually linking against the ClangImporter library.
If the current source file really can't import ClangModule.h, it can
still fall back to checking against the DeclContext's getContextKind()
(and indeed AST currently does in a few places).
Swift SVN r6695
This is a temporary hack until we properly make these carry
their own generic parameters.
This removes the last valid way to get UnboundGenericTypes in
a checked program.
Swift SVN r6373
