This class formalizes the common case of the "trailing allocation" idiom we use
frequently. I didn't spot any true bugs while making this change, but I did see
places where we were using the wrong pointer type or casting through void* for
no good reason. This will keep us honest.
I'll get to the other libraries soon.
This eliminates some minor overheads, but mostly it eliminates
a lot of conceptual complexity due to the overhead basically
appearing outside of its context.
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.
Expose Substitution's archetype, replacement, and conformances only through getters so we can actually assert invariants about them. To start, require replacement types to be materializable in order to catch cases where the type-checker tries to bind type variables to lvalue or inout types, and require the conformance array to match the number of protocol conformances required by the archetype. This exposes some latent bugs in the test suite I've marked as failures for now:
- test/Constraints/overload.swift was quietly suffering from <rdar://problem/17507421>, but we didn't notice because we never tried to codegen it.
- test/SIL/Parser/array_roundtrip.swift doesn't correctly roundtrip substitutions, which I filed as <rdar://problem/17781140>.
Swift SVN r20418
The need to hide Self from AllArchetypes of a GenericParamList is (almost) defined away by @cc(witness_method); IRGen now knows how to do the right thing for witnesses regardless of their generic signature. Eliminating this special case from the AST allows us to clear up a bunch of ugly hacks that piled up elsewhere to try to accommodate that special case, and makes the prospect of moving IRGen's PolymorphicConvention to interface types more manageable.
We do need an unfortunate hack to suppress emitting associated archetypes of Self when considering an archetype as the polymorphic source for a witness, since we can't actually pass those through the witness CC without breaking ABI compatibility between generic signatures.
Swift SVN r13663
This matches what SIL expects for generic function applications. Add a 'getPrimarySubstitutions' convenience method to ConcreteDeclRef.
Swift SVN r11579
The new ConcreteDeclRef class provides a possibly-speciaized reference
to a declaration, which allows DynamicMemberRefExpr to refer to both
generic and non-generic members. without having to split the AST node.
Swift SVN r7839
