introduce a common superclass, SILNode.
This is in preparation for allowing instructions to have multiple
results. It is also a somewhat more elegant representation for
instructions that have zero results. Instructions that are known
to have exactly one result inherit from a class, SingleValueInstruction,
that subclasses both ValueBase and SILInstruction. Some care must be
taken when working with SILNode pointers and testing for equality;
please see the comment on SILNode for more information.
A number of SIL passes needed to be updated in order to handle this
new distinction between SIL values and SIL instructions.
Note that the SIL parser is now stricter about not trying to assign
a result value from an instruction (like 'return' or 'strong_retain')
that does not produce any.
Previously we stored this inside each default argument
initializer context. This was overkill, because it is
the same for all default arguments in a single function,
and also insufficient, because initializer contexts are
not serialized and thus not available in SILGen when
the function is in a different module.
Instead store it directly inside the function and
serialize it.
NFC for now, since SILGen isn't using this yet.
This commit contains:
-) adding the new instructions + infrastructure, like parsing, printing, etc.
-) support in IRGen to generate global object-variables (i.e. "heap" objects) which are statically initialized in the data section.
-) IRGen for global_value which lazily initializes the object header and returns a reference to the object.
For details see the documentation of the new instructions in SIL.rst.
Remove the cast consumption kind from all unconditional casts. It
doesn't make sense for unconditional casts, complicates SIL ownership,
and wasn't fully supported for all variants. Copies should be
explicit.
Consider a class hierarchy like the following:
class Base {
func m1() {}
func m2() {}
}
class Derived : Base {
override func m2() {}
func m3() {}
}
The SIL vtable for 'Derived' now records that the entry for m1
is inherited, the entry for m2 is an override, and the entry
for m3 is a new entry:
sil_vtable Derived {
#Base.m1!1: (Base) -> () -> () : _T01a4BaseC2m1yyF [inherited]
#Base.m2!1: (Base) -> () -> () : _T01a7DerivedC2m2yyF [override]
#Derived.m3!1: (Derived) -> () -> () : _T01a7DerivedC2m3yyF
}
This additional information will allow IRGen to emit the vtable
for Derived resiliently, without referencing the symbol for
the inherited method m1() directly.
This has the same semantics as open_existential_box, but returns an object value
instead of an address.
This is used in SIL opaque values mode. Attempting to reuse open_existential_box
in this mode causes SIL type inconsistencies that are too difficult to work
around. Adding this instruction allows for consistent handling of opaque values.
The original versions of several of these currently redundant instructions will
be removed once the SIL representation stabilizes.
These instructions have the same semantics as the *ExistentialAddr instructions
but operate directly on the existential value, not its address.
This is in preparation for adding ExistentialBoxValue instructions.
The previous name would cause impossible confusion with "opaque existentials"
and "opaque existential boxes".
Till now createApply, createTryApply, createPartialApply were taking some arguments like SubstCalleeType or ResultType. But these arguments are redundant and can be easily derived from other arguments of these functions. There is no need to put the burden of their computation on the clients of these APIs.
The removal of these redundant parameters simplifies the APIs and reduces the possibility of providing mismatched types by clients, which often happened in the past.
All we need to store is whether the SILDeclRef directly
references the declaration, or if it references a curry
thunk, and we already have an isCurried bit for that.
Also, add a third [serializable] state for functions whose bodies we
*can* serialize, but only do so if they're referenced from another
serialized function.
This will be used for bodies synthesized for imported definitions,
such as init(rawValue:), etc, and various thunks, but for now this
change is NFC.
to correctly handle generalized protocol requirements.
The major missing pieces here are that the conformance search
algorithms in both the AST (type substitution) and IRGen
(witness table reference emission) need to be rewritten to
back-track requirement sources, and the AST needs to actually
represent this stuff in NormalProtocolConformances instead
of just doing ???.
The new generality isn't tested yet; I'm looking into that,
but I wanted to get the abstractions in place first.
This is the lifetime ending variant of fix_lifetime. It is a lie to the
ownership verifier that a value is being consumed along a path. Its intention is
to be used to allow for the static verification of ownership in deallocating
deinits which for compatibility with objective-c have weird ownership behavior.
See the commit merged with this commit for more information.
Once we move to a copy-on-write implementation of existential value buffers we
can no longer consume or destroy values of an opened existential unless the
buffer is uniquely owned.
Therefore we need to track the allowed operation on opened values.
Add qualifiers "mutable_access" and "immutable_access" to open_existential_addr
instructions to indicate the allowed access to the opened value.
Once we move to a copy-on-write implementation, an "open_existential_addr
mutable_access" instruction will ensure unique ownership of the value buffer.
This reverts commit 1b3d29a163, reversing
changes made to b32424953e.
We're seeing a handful of issues from turning on inlining of generics,
so I'm reverting to unblock the bots.
Separate formal lowered types from SIL types.
The SIL type of an argument will depend on the SIL module's conventions.
The module conventions are determined by the SIL stage and LangOpts.
Almost NFC, but specialized manglings are broken incidentally as a result of
fixes to the way passes handle book-keeping of aruments. The mangler is fixed in
the subsequent commit.
Otherwise, NFC is intended, but quite possible do to rewriting the logic in many
places.
