Files
swift-mirror/lib/AST/ProtocolConformance.cpp
Doug Gregor ecd830e342 Rework BuiltinProtocolConformance to be more like NormalProtocolConformance.
Give BuiltinProtocolConformance a generic signature, which can be used to
describe the generic parameters used within the builtin conformance, e.g.,
`<T1, T2, T3>` for a tuple type `(T1, T2, T3)`. Also store the
conditional requirements as trailing objects, requiring them to be
precomputed by whatever builds the conformances. Together, this means
that builtin protocol conformances act like normal conformances with
respect to conditional requirements and substitutions: they will be
defined generically, then a specialized conformance will be layered on
top to provide the substitutions.
2021-07-27 23:49:27 -07:00

1658 lines
58 KiB
C++

//===--- ProtocolConformance.cpp - AST Protocol Conformance ---------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2020 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See https://swift.org/LICENSE.txt for license information
// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
//
// This file implements the protocol conformance data structures.
//
//===----------------------------------------------------------------------===//
#include "swift/AST/ProtocolConformance.h"
#include "ConformanceLookupTable.h"
#include "swift/AST/ASTContext.h"
#include "swift/AST/Availability.h"
#include "swift/AST/Decl.h"
#include "swift/AST/FileUnit.h"
#include "swift/AST/GenericEnvironment.h"
#include "swift/AST/LazyResolver.h"
#include "swift/AST/Module.h"
#include "swift/AST/TypeCheckRequests.h"
#include "swift/AST/TypeWalker.h"
#include "swift/AST/Types.h"
#include "swift/AST/TypeCheckRequests.h"
#include "swift/Basic/Statistic.h"
#include "llvm/ADT/MapVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/ADT/TinyPtrVector.h"
#include "llvm/Support/PrettyStackTrace.h"
#include "llvm/Support/SaveAndRestore.h"
#define DEBUG_TYPE "AST"
STATISTIC(NumConformanceLookupTables, "# of conformance lookup tables built");
using namespace swift;
Witness::Witness(ValueDecl *decl, SubstitutionMap substitutions,
GenericEnvironment *syntheticEnv,
SubstitutionMap reqToSynthesizedEnvSubs) {
if (!syntheticEnv && substitutions.empty() &&
reqToSynthesizedEnvSubs.empty()) {
storage = decl;
return;
}
auto &ctx = decl->getASTContext();
auto declRef = ConcreteDeclRef(decl, substitutions);
auto storedMem = ctx.Allocate(sizeof(StoredWitness), alignof(StoredWitness));
auto stored = new (storedMem) StoredWitness{declRef, syntheticEnv,
reqToSynthesizedEnvSubs};
storage = stored;
}
void Witness::dump() const { dump(llvm::errs()); }
void Witness::dump(llvm::raw_ostream &out) const {
// FIXME: Implement!
}
ProtocolConformanceRef::ProtocolConformanceRef(ProtocolDecl *protocol,
ProtocolConformance *conf) {
assert(protocol != nullptr &&
"cannot construct ProtocolConformanceRef with null protocol");
if (conf) {
assert(protocol == conf->getProtocol() && "protocol conformance mismatch");
Union = conf;
} else {
Union = protocol;
}
}
ProtocolDecl *ProtocolConformanceRef::getRequirement() const {
assert(!isInvalid());
if (isConcrete()) {
return getConcrete()->getProtocol();
} else {
return getAbstract();
}
}
ProtocolConformanceRef
ProtocolConformanceRef::subst(Type origType,
SubstitutionMap subMap,
SubstOptions options) const {
return subst(origType,
QuerySubstitutionMap{subMap},
LookUpConformanceInSubstitutionMap(subMap),
options);
}
ProtocolConformanceRef
ProtocolConformanceRef::subst(Type origType,
TypeSubstitutionFn subs,
LookupConformanceFn conformances,
SubstOptions options) const {
if (isInvalid())
return *this;
// If we have a concrete conformance, we need to substitute the
// conformance to apply to the new type.
if (isConcrete())
return ProtocolConformanceRef(getConcrete()->subst(subs, conformances,
options));
// If the type is an opaque archetype, the conformance will remain abstract,
// unless we're specifically substituting opaque types.
if (auto origArchetype = origType->getAs<ArchetypeType>()) {
if (!options.contains(SubstFlags::SubstituteOpaqueArchetypes)
&& isa<OpaqueTypeArchetypeType>(origArchetype->getRoot())) {
return *this;
}
}
// Otherwise, compute the substituted type.
auto substType = origType.subst(subs, conformances, options);
auto *proto = getRequirement();
// If the type is an existential, it must be self-conforming.
if (substType->isExistentialType()) {
auto optConformance =
proto->getModuleContext()->lookupExistentialConformance(substType,
proto);
if (optConformance)
return optConformance;
return ProtocolConformanceRef::forInvalid();
}
// Check the conformance map.
return conformances(origType->getCanonicalType(), substType, proto);
}
ProtocolConformanceRef ProtocolConformanceRef::mapConformanceOutOfContext() const {
if (!isConcrete())
return *this;
auto *concrete = getConcrete()->subst(
[](SubstitutableType *type) -> Type {
if (auto *archetypeType = type->getAs<ArchetypeType>())
return archetypeType->getInterfaceType();
return type;
},
MakeAbstractConformanceForGenericType());
return ProtocolConformanceRef(concrete);
}
Type
ProtocolConformanceRef::getTypeWitnessByName(Type type, Identifier name) const {
assert(!isInvalid());
// Find the named requirement.
ProtocolDecl *proto = getRequirement();
auto *assocType = proto->getAssociatedType(name);
// FIXME: Shouldn't this be a hard error?
if (!assocType)
return ErrorType::get(proto->getASTContext());
return assocType->getDeclaredInterfaceType().subst(
SubstitutionMap::getProtocolSubstitutions(proto, type, *this));
}
ConcreteDeclRef
ProtocolConformanceRef::getWitnessByName(Type type, DeclName name) const {
// Find the named requirement.
auto *proto = getRequirement();
auto *requirement = proto->getSingleRequirement(name);
if (requirement == nullptr)
return ConcreteDeclRef();
// For a type with dependent conformance, just return the requirement from
// the protocol. There are no protocol conformance tables.
if (!isConcrete()) {
auto subs = SubstitutionMap::getProtocolSubstitutions(proto, type, *this);
return ConcreteDeclRef(requirement, subs);
}
return getConcrete()->getWitnessDeclRef(requirement);
}
void *ProtocolConformance::operator new(size_t bytes, ASTContext &context,
AllocationArena arena,
unsigned alignment) {
return context.Allocate(bytes, alignment, arena);
}
#define CONFORMANCE_SUBCLASS_DISPATCH(Method, Args) \
switch (getKind()) { \
case ProtocolConformanceKind::Normal: \
return cast<NormalProtocolConformance>(this)->Method Args; \
case ProtocolConformanceKind::Self: \
return cast<SelfProtocolConformance>(this)->Method Args; \
case ProtocolConformanceKind::Specialized: \
return cast<SpecializedProtocolConformance>(this)->Method Args; \
case ProtocolConformanceKind::Inherited: \
return cast<InheritedProtocolConformance>(this)->Method Args; \
case ProtocolConformanceKind::Builtin: \
static_assert(&ProtocolConformance::Method != \
&BuiltinProtocolConformance::Method, \
"Must override BuiltinProtocolConformance::" #Method); \
return cast<BuiltinProtocolConformance>(this)->Method Args; \
} \
llvm_unreachable("bad ProtocolConformanceKind");
#define ROOT_CONFORMANCE_SUBCLASS_DISPATCH(Method, Args) \
switch (getKind()) { \
case ProtocolConformanceKind::Normal: \
return cast<NormalProtocolConformance>(this)->Method Args; \
case ProtocolConformanceKind::Self: \
return cast<SelfProtocolConformance>(this)->Method Args; \
case ProtocolConformanceKind::Specialized: \
case ProtocolConformanceKind::Inherited: \
case ProtocolConformanceKind::Builtin: \
llvm_unreachable("not a root conformance"); \
} \
llvm_unreachable("bad ProtocolConformanceKind");
/// Get the protocol being conformed to.
ProtocolDecl *ProtocolConformance::getProtocol() const {
CONFORMANCE_SUBCLASS_DISPATCH(getProtocol, ())
}
DeclContext *ProtocolConformance::getDeclContext() const {
CONFORMANCE_SUBCLASS_DISPATCH(getDeclContext, ())
}
/// Retrieve the state of this conformance.
ProtocolConformanceState ProtocolConformance::getState() const {
CONFORMANCE_SUBCLASS_DISPATCH(getState, ())
}
ConformanceEntryKind ProtocolConformance::getSourceKind() const {
CONFORMANCE_SUBCLASS_DISPATCH(getSourceKind, ())
}
NormalProtocolConformance *ProtocolConformance::getImplyingConformance() const {
CONFORMANCE_SUBCLASS_DISPATCH(getImplyingConformance, ())
}
bool
ProtocolConformance::hasTypeWitness(AssociatedTypeDecl *assocType) const {
CONFORMANCE_SUBCLASS_DISPATCH(hasTypeWitness, (assocType));
}
TypeWitnessAndDecl
ProtocolConformance::getTypeWitnessAndDecl(AssociatedTypeDecl *assocType,
SubstOptions options) const {
CONFORMANCE_SUBCLASS_DISPATCH(getTypeWitnessAndDecl,
(assocType, options))
}
Type ProtocolConformance::getTypeWitness(AssociatedTypeDecl *assocType,
SubstOptions options) const {
return getTypeWitnessAndDecl(assocType, options).getWitnessType();
}
ConcreteDeclRef
ProtocolConformance::getWitnessDeclRef(ValueDecl *requirement) const {
CONFORMANCE_SUBCLASS_DISPATCH(getWitnessDeclRef, (requirement))
}
ValueDecl *ProtocolConformance::getWitnessDecl(ValueDecl *requirement) const {
switch (getKind()) {
case ProtocolConformanceKind::Normal:
return cast<NormalProtocolConformance>(this)->getWitness(requirement)
.getDecl();
case ProtocolConformanceKind::Self:
return cast<SelfProtocolConformance>(this)->getWitness(requirement)
.getDecl();
case ProtocolConformanceKind::Inherited:
return cast<InheritedProtocolConformance>(this)
->getInheritedConformance()->getWitnessDecl(requirement);
case ProtocolConformanceKind::Specialized:
return cast<SpecializedProtocolConformance>(this)
->getGenericConformance()->getWitnessDecl(requirement);
case ProtocolConformanceKind::Builtin:
return requirement;
}
llvm_unreachable("unhandled kind");
}
/// Determine whether the witness for the given requirement
/// is either the default definition or was otherwise deduced.
bool ProtocolConformance::
usesDefaultDefinition(AssociatedTypeDecl *requirement) const {
CONFORMANCE_SUBCLASS_DISPATCH(usesDefaultDefinition, (requirement))
}
GenericEnvironment *ProtocolConformance::getGenericEnvironment() const {
switch (getKind()) {
case ProtocolConformanceKind::Inherited:
case ProtocolConformanceKind::Normal:
case ProtocolConformanceKind::Self:
// If we have a normal or inherited protocol conformance, look for its
// generic parameters.
return getDeclContext()->getGenericEnvironmentOfContext();
case ProtocolConformanceKind::Specialized:
case ProtocolConformanceKind::Builtin:
// If we have a specialized protocol conformance, since we do not support
// currently partial specialization, we know that it cannot have any open
// type variables.
//
// FIXME: We could return a meaningful GenericEnvironment here
return nullptr;
}
llvm_unreachable("Unhandled ProtocolConformanceKind in switch.");
}
GenericSignature ProtocolConformance::getGenericSignature() const {
switch (getKind()) {
case ProtocolConformanceKind::Inherited:
case ProtocolConformanceKind::Normal:
case ProtocolConformanceKind::Self:
// If we have a normal or inherited protocol conformance, look for its
// generic signature.
return getDeclContext()->getGenericSignatureOfContext();
case ProtocolConformanceKind::Builtin:
return cast<BuiltinProtocolConformance>(this)->getGenericSignature();
case ProtocolConformanceKind::Specialized:
// If we have a specialized protocol conformance, since we do not support
// currently partial specialization, we know that it cannot have any open
// type variables.
return nullptr;
}
llvm_unreachable("Unhandled ProtocolConformanceKind in switch.");
}
SubstitutionMap ProtocolConformance::getSubstitutions(ModuleDecl *M) const {
// Walk down to the base NormalProtocolConformance.
SubstitutionMap subMap;
const ProtocolConformance *parent = this;
while (!isa<RootProtocolConformance>(parent)) {
switch (parent->getKind()) {
case ProtocolConformanceKind::Normal:
case ProtocolConformanceKind::Self:
case ProtocolConformanceKind::Builtin:
llvm_unreachable("should have exited the loop?!");
case ProtocolConformanceKind::Inherited:
parent =
cast<InheritedProtocolConformance>(parent)->getInheritedConformance();
break;
case ProtocolConformanceKind::Specialized: {
auto SC = cast<SpecializedProtocolConformance>(parent);
parent = SC->getGenericConformance();
assert(subMap.empty() && "multiple conformance specializations?!");
subMap = SC->getSubstitutionMap();
break;
}
}
}
// Found something; we're done!
if (!subMap.empty())
return subMap;
// If the normal conformance is for a generic type, and we didn't hit a
// specialized conformance, collect the substitutions from the generic type.
// FIXME: The AST should do this for us.
const NormalProtocolConformance *normalC =
dyn_cast<NormalProtocolConformance>(parent);
if (!normalC)
return SubstitutionMap();
if (!normalC->getType()->isSpecialized())
return SubstitutionMap();
auto *DC = normalC->getDeclContext();
return normalC->getType()->getContextSubstitutionMap(M, DC);
}
bool RootProtocolConformance::isInvalid() const {
ROOT_CONFORMANCE_SUBCLASS_DISPATCH(isInvalid, ())
}
SourceLoc RootProtocolConformance::getLoc() const {
ROOT_CONFORMANCE_SUBCLASS_DISPATCH(getLoc, ())
}
bool
RootProtocolConformance::isWeakImported(ModuleDecl *fromModule) const {
auto *dc = getDeclContext();
if (dc->getParentModule() == fromModule)
return false;
// If the protocol is weak imported, so are any conformances to it.
if (getProtocol()->isWeakImported(fromModule))
return true;
// If the conforming type is weak imported, so are any of its conformances.
if (auto *nominal = getType()->getAnyNominal())
if (nominal->isWeakImported(fromModule))
return true;
// If the conformance is declared in an extension with the @_weakLinked
// attribute, it is weak imported.
if (auto *ext = dyn_cast<ExtensionDecl>(dc))
if (ext->isWeakImported(fromModule))
return true;
return false;
}
bool RootProtocolConformance::hasWitness(ValueDecl *requirement) const {
ROOT_CONFORMANCE_SUBCLASS_DISPATCH(hasWitness, (requirement))
}
bool NormalProtocolConformance::isRetroactive() const {
auto module = getDeclContext()->getParentModule();
// If the conformance occurs in the same module as the protocol definition,
// this is not a retroactive conformance.
auto protocolModule = getProtocol()->getDeclContext()->getParentModule();
if (module == protocolModule)
return false;
// If the conformance occurs in the same module as the conforming type
// definition, this is not a retroactive conformance.
if (auto nominal = getType()->getAnyNominal()) {
auto nominalModule = nominal->getParentModule();
// Consider the overlay module to be the "home" of a nominal type
// defined in a Clang module.
if (auto nominalLoadedModule =
dyn_cast<LoadedFile>(nominal->getModuleScopeContext())) {
if (auto overlayModule = nominalLoadedModule->getOverlayModule())
nominalModule = overlayModule;
}
if (module == nominalModule)
return false;
}
// Everything else is retroactive.
return true;
}
bool NormalProtocolConformance::isSynthesizedNonUnique() const {
if (auto *file = dyn_cast<FileUnit>(getDeclContext()->getModuleScopeContext()))
return file->getKind() == FileUnitKind::ClangModule;
return false;
}
bool NormalProtocolConformance::isResilient() const {
// If the type is non-resilient or the module we're in is non-resilient, the
// conformance is non-resilient.
// FIXME: Looking at the type is not the right long-term solution. We need an
// explicit mechanism for declaring conformances as 'fragile', or even
// individual witnesses.
if (!getType()->getAnyNominal()->isResilient())
return false;
return getDeclContext()->getParentModule()->isResilient();
}
Optional<ArrayRef<Requirement>>
ProtocolConformance::getConditionalRequirementsIfAvailable() const {
CONFORMANCE_SUBCLASS_DISPATCH(getConditionalRequirementsIfAvailable, ());
}
ArrayRef<Requirement> ProtocolConformance::getConditionalRequirements() const {
CONFORMANCE_SUBCLASS_DISPATCH(getConditionalRequirements, ());
}
Optional<ArrayRef<Requirement>>
ProtocolConformanceRef::getConditionalRequirementsIfAvailable() const {
if (isConcrete())
return getConcrete()->getConditionalRequirementsIfAvailable();
else
// An abstract conformance is never conditional: any conditionality in the
// concrete types that will eventually pass through this at runtime is
// completely pre-checked and packaged up.
return ArrayRef<Requirement>();
}
ArrayRef<Requirement>
ProtocolConformanceRef::getConditionalRequirements() const {
if (isConcrete())
return getConcrete()->getConditionalRequirements();
else
// An abstract conformance is never conditional, as above.
return {};
}
Optional<ArrayRef<Requirement>>
NormalProtocolConformance::getConditionalRequirementsIfAvailable() const {
const auto &eval = getDeclContext()->getASTContext().evaluator;
if (eval.hasActiveRequest(ConditionalRequirementsRequest{
const_cast<NormalProtocolConformance *>(this)})) {
return None;
}
return getConditionalRequirements();
}
llvm::ArrayRef<Requirement>
NormalProtocolConformance::getConditionalRequirements() const {
const auto ext = dyn_cast<ExtensionDecl>(getDeclContext());
if (ext && ext->isComputingGenericSignature()) {
return {};
}
return evaluateOrDefault(getProtocol()->getASTContext().evaluator,
ConditionalRequirementsRequest{
const_cast<NormalProtocolConformance *>(this)},
{});
}
llvm::ArrayRef<Requirement>
ConditionalRequirementsRequest::evaluate(Evaluator &evaluator,
NormalProtocolConformance *NPC) const {
// A non-extension conformance won't have conditional requirements.
const auto ext = dyn_cast<ExtensionDecl>(NPC->getDeclContext());
if (!ext) {
return {};
}
// If the extension is invalid, it won't ever get a signature, so we
// "succeed" with an empty result instead.
if (ext->isInvalid()) {
return {};
}
// A non-generic type won't have conditional requirements.
const auto typeSig = ext->getExtendedNominal()->getGenericSignature();
if (!typeSig) {
return {};
}
const auto extensionSig = ext->getGenericSignature();
// The extension signature should be a superset of the type signature, meaning
// every thing in the type signature either is included too or is implied by
// something else. The most important bit is having the same type
// parameters. (NB. if/when Swift gets parameterized extensions, this needs to
// change.)
assert(typeSig.getCanonicalSignature().getGenericParams() ==
extensionSig.getCanonicalSignature().getGenericParams());
// Find the requirements in the extension that aren't proved by the original
// type, these are the ones that make the conformance conditional.
const auto unsatReqs = extensionSig->requirementsNotSatisfiedBy(typeSig);
if (unsatReqs.empty())
return {};
return NPC->getProtocol()->getASTContext().AllocateCopy(unsatReqs);
}
void NormalProtocolConformance::setSignatureConformances(
ArrayRef<ProtocolConformanceRef> conformances) {
if (conformances.empty()) {
SignatureConformances = { };
return;
}
auto &ctx = getProtocol()->getASTContext();
SignatureConformances = ctx.AllocateCopy(conformances);
#if !NDEBUG
unsigned idx = 0;
for (const auto &req : getProtocol()->getRequirementSignature()) {
if (req.getKind() == RequirementKind::Conformance) {
assert(!conformances[idx].isConcrete() ||
!conformances[idx].getConcrete()->getType()->hasArchetype() &&
"Should have interface types here");
assert(idx < conformances.size());
assert(conformances[idx].isInvalid() ||
conformances[idx].getRequirement() == req.getProtocolDecl());
++idx;
}
}
assert(idx == conformances.size() && "Too many conformances");
#endif
}
void NormalProtocolConformance::resolveLazyInfo() const {
assert(Loader);
auto *loader = Loader;
auto *mutableThis = const_cast<NormalProtocolConformance *>(this);
mutableThis->Loader = nullptr;
loader->finishNormalConformance(mutableThis, LoaderContextData);
}
void NormalProtocolConformance::setLazyLoader(LazyConformanceLoader *loader,
uint64_t contextData) {
assert(!Loader && "already has a loader");
Loader = loader;
LoaderContextData = contextData;
}
namespace {
class PrettyStackTraceRequirement : public llvm::PrettyStackTraceEntry {
const char *Action;
const ProtocolConformance *Conformance;
ValueDecl *Requirement;
public:
PrettyStackTraceRequirement(const char *action,
const ProtocolConformance *conformance,
ValueDecl *requirement)
: Action(action), Conformance(conformance), Requirement(requirement) { }
void print(llvm::raw_ostream &out) const override {
out << "While " << Action << " requirement ";
Requirement->dumpRef(out);
out << " in conformance ";
Conformance->printName(out);
out << "\n";
}
};
} // end anonymous namespace
bool NormalProtocolConformance::hasTypeWitness(
AssociatedTypeDecl *assocType) const {
if (Loader)
resolveLazyInfo();
auto found = TypeWitnesses.find(assocType);
if (found != TypeWitnesses.end()) {
return !found->getSecond().getWitnessType().isNull();
}
return false;
}
TypeWitnessAndDecl
NormalProtocolConformance::getTypeWitnessAndDecl(AssociatedTypeDecl *assocType,
SubstOptions options) const {
if (Loader)
resolveLazyInfo();
// Check whether we already have a type witness.
auto known = TypeWitnesses.find(assocType);
if (known != TypeWitnesses.end())
return known->second;
// If there is a tentative-type-witness function, use it.
if (options.getTentativeTypeWitness) {
if (Type witnessType =
Type(options.getTentativeTypeWitness(this, assocType)))
return { witnessType, nullptr };
}
// If this conformance is in a state where it is inferring type witnesses but
// we didn't find anything, fail.
if (getState() == ProtocolConformanceState::CheckingTypeWitnesses) {
return { Type(), nullptr };
}
// If the conditional requirements aren't known, we can't properly run
// inference.
if (!getConditionalRequirementsIfAvailable()) {
return TypeWitnessAndDecl();
}
return evaluateOrDefault(
assocType->getASTContext().evaluator,
TypeWitnessRequest{const_cast<NormalProtocolConformance *>(this),
assocType},
TypeWitnessAndDecl());
}
TypeWitnessAndDecl NormalProtocolConformance::getTypeWitnessUncached(
AssociatedTypeDecl *requirement) const {
auto entry = TypeWitnesses.find(requirement);
if (entry == TypeWitnesses.end()) {
return TypeWitnessAndDecl();
}
return entry->second;
}
void NormalProtocolConformance::setTypeWitness(AssociatedTypeDecl *assocType,
Type type,
TypeDecl *typeDecl) const {
assert(getProtocol() == cast<ProtocolDecl>(assocType->getDeclContext()) &&
"associated type in wrong protocol");
assert((TypeWitnesses.count(assocType) == 0 ||
TypeWitnesses[assocType].getWitnessType().isNull()) &&
"Type witness already known");
assert((!isComplete() || isInvalid()) && "Conformance already complete?");
assert(!type->hasArchetype() && "type witnesses must be interface types");
TypeWitnesses[assocType] = {type, typeDecl};
}
Type ProtocolConformance::getAssociatedType(Type assocType) const {
assert(assocType->isTypeParameter() &&
"associated type must be a type parameter");
ProtocolConformanceRef ref(const_cast<ProtocolConformance*>(this));
return ref.getAssociatedType(getType(), assocType);
}
Type ProtocolConformanceRef::getAssociatedType(Type conformingType,
Type assocType) const {
assert(!isConcrete() || getConcrete()->getType()->isEqual(conformingType));
auto type = assocType->getCanonicalType();
auto proto = getRequirement();
// Fast path for generic parameters.
if (isa<GenericTypeParamType>(type)) {
assert(type->isEqual(proto->getSelfInterfaceType()) &&
"type parameter in protocol was not Self");
return conformingType;
}
// Fast path for dependent member types on 'Self' of our associated types.
auto memberType = cast<DependentMemberType>(type);
if (memberType.getBase()->isEqual(proto->getSelfInterfaceType()) &&
memberType->getAssocType()->getProtocol() == proto &&
isConcrete())
return getConcrete()->getTypeWitness(memberType->getAssocType());
// General case: consult the substitution map.
auto substMap =
SubstitutionMap::getProtocolSubstitutions(proto, conformingType, *this);
return type.subst(substMap);
}
ProtocolConformanceRef
ProtocolConformanceRef::getAssociatedConformance(Type conformingType,
Type assocType,
ProtocolDecl *protocol) const {
// If this is a concrete conformance, look up the associated conformance.
if (isConcrete()) {
auto conformance = getConcrete();
assert(conformance->getType()->isEqual(conformingType));
return conformance->getAssociatedConformance(assocType, protocol);
}
// Otherwise, apply the substitution {self -> conformingType}
// to the abstract conformance requirement laid upon the dependent type
// by the protocol.
auto subMap =
SubstitutionMap::getProtocolSubstitutions(getRequirement(),
conformingType, *this);
auto abstractConf = ProtocolConformanceRef(protocol);
return abstractConf.subst(assocType, subMap);
}
ProtocolConformanceRef
ProtocolConformance::getAssociatedConformance(Type assocType,
ProtocolDecl *protocol) const {
CONFORMANCE_SUBCLASS_DISPATCH(getAssociatedConformance,
(assocType, protocol))
}
ProtocolConformanceRef
NormalProtocolConformance::getAssociatedConformance(Type assocType,
ProtocolDecl *protocol) const {
assert(assocType->isTypeParameter() &&
"associated type must be a type parameter");
// Fill in the signature conformances, if we haven't done so yet.
if (getSignatureConformances().empty()) {
const_cast<NormalProtocolConformance *>(this)->finishSignatureConformances();
}
assert(!getSignatureConformances().empty() &&
"signature conformances not yet computed");
unsigned conformanceIndex = 0;
for (const auto &reqt : getProtocol()->getRequirementSignature()) {
if (reqt.getKind() == RequirementKind::Conformance) {
// Is this the conformance we're looking for?
if (reqt.getFirstType()->isEqual(assocType) &&
reqt.getProtocolDecl() == protocol)
return getSignatureConformances()[conformanceIndex];
++conformanceIndex;
}
}
llvm_unreachable(
"requested conformance was not a direct requirement of the protocol");
}
/// A stripped-down version of Type::subst that only works on the protocol
/// Self type wrapped in zero or more DependentMemberTypes.
static Type
recursivelySubstituteBaseType(ModuleDecl *module,
NormalProtocolConformance *conformance,
DependentMemberType *depMemTy) {
Type origBase = depMemTy->getBase();
// Recursive case.
if (auto *depBase = origBase->getAs<DependentMemberType>()) {
Type substBase = recursivelySubstituteBaseType(
module, conformance, depBase);
return depMemTy->substBaseType(module, substBase);
}
// Base case. The associated type's protocol should be either the
// conformance protocol or an inherited protocol.
auto *reqProto = depMemTy->getAssocType()->getProtocol();
assert(origBase->isEqual(reqProto->getSelfInterfaceType()));
ProtocolConformance *reqConformance = conformance;
// If we have an inherited protocol just look up the conformance.
if (reqProto != conformance->getProtocol()) {
reqConformance = module->lookupConformance(conformance->getType(), reqProto)
.getConcrete();
}
return reqConformance->getTypeWitness(depMemTy->getAssocType());
}
/// Collect conformances for the requirement signature.
void NormalProtocolConformance::finishSignatureConformances() {
if (!SignatureConformances.empty())
return;
auto *proto = getProtocol();
auto reqSig = proto->getRequirementSignature();
if (reqSig.empty())
return;
SmallVector<ProtocolConformanceRef, 4> reqConformances;
for (const auto &req : reqSig) {
if (req.getKind() != RequirementKind::Conformance)
continue;
ModuleDecl *module = getDeclContext()->getParentModule();
Type substTy;
auto origTy = req.getFirstType();
if (origTy->isEqual(proto->getSelfInterfaceType())) {
substTy = getType();
} else {
auto *depMemTy = origTy->castTo<DependentMemberType>();
substTy = recursivelySubstituteBaseType(module, this, depMemTy);
}
auto reqProto = req.getProtocolDecl();
// Looking up a conformance for a contextual type and mapping the
// conformance context produces a more accurate result than looking
// up a conformance from an interface type.
//
// This can happen if the conformance has an associated conformance
// depending on an associated type that is made concrete in a
// refining protocol.
//
// That is, the conformance of an interface type G<T> : P really
// depends on the generic signature of the current context, because
// performing the lookup in a "more" constrained extension than the
// one where the conformance was defined must produce concrete
// conformances.
//
// FIXME: Eliminate this, perhaps by adding a variant of
// lookupConformance() taking a generic signature.
if (substTy->hasTypeParameter())
substTy = getDeclContext()->mapTypeIntoContext(substTy);
reqConformances.push_back(module->lookupConformance(substTy, reqProto)
.mapConformanceOutOfContext());
}
setSignatureConformances(reqConformances);
}
Witness RootProtocolConformance::getWitness(ValueDecl *requirement) const {
ROOT_CONFORMANCE_SUBCLASS_DISPATCH(getWitness, (requirement))
}
/// Retrieve the value witness corresponding to the given requirement.
Witness NormalProtocolConformance::getWitness(ValueDecl *requirement) const {
assert(!isa<AssociatedTypeDecl>(requirement) && "Request type witness");
assert(requirement->isProtocolRequirement() && "Not a requirement");
if (Loader)
resolveLazyInfo();
return evaluateOrDefault(
requirement->getASTContext().evaluator,
ValueWitnessRequest{const_cast<NormalProtocolConformance *>(this),
requirement},
Witness());
}
Witness
NormalProtocolConformance::getWitnessUncached(ValueDecl *requirement) const {
auto entry = Mapping.find(requirement);
if (entry == Mapping.end()) {
return Witness();
}
return entry->second;
}
Witness SelfProtocolConformance::getWitness(ValueDecl *requirement) const {
return Witness(requirement, SubstitutionMap(), nullptr, SubstitutionMap());
}
ConcreteDeclRef
RootProtocolConformance::getWitnessDeclRef(ValueDecl *requirement) const {
if (auto witness = getWitness(requirement)) {
auto *witnessDecl = witness.getDecl();
// If the witness is generic, you have to call getWitness() and build
// your own substitutions in terms of the synthetic environment.
if (auto *witnessDC = dyn_cast<DeclContext>(witnessDecl))
assert(!witnessDC->isInnermostContextGeneric());
// If the witness is not generic, use type substitutions from the
// witness's parent. Don't use witness.getSubstitutions(), which
// are written in terms of the synthetic environment.
auto subs =
getType()->getContextSubstitutionMap(getDeclContext()->getParentModule(),
witnessDecl->getDeclContext());
return ConcreteDeclRef(witness.getDecl(), subs);
}
return ConcreteDeclRef();
}
void NormalProtocolConformance::setWitness(ValueDecl *requirement,
Witness witness) const {
assert(!isa<AssociatedTypeDecl>(requirement) && "Request type witness");
assert(getProtocol() == cast<ProtocolDecl>(requirement->getDeclContext()) &&
"requirement in wrong protocol");
assert(Mapping.count(requirement) == 0 && "Witness already known");
assert((!isComplete() || isInvalid() ||
requirement->getAttrs().hasAttribute<OptionalAttr>() ||
requirement->getAttrs().isUnavailable(
requirement->getASTContext())) &&
"Conformance already complete?");
Mapping[requirement] = witness;
}
SpecializedProtocolConformance::SpecializedProtocolConformance(
Type conformingType,
ProtocolConformance *genericConformance,
SubstitutionMap substitutions)
: ProtocolConformance(ProtocolConformanceKind::Specialized, conformingType),
GenericConformance(genericConformance),
GenericSubstitutions(substitutions)
{
assert(genericConformance->getKind() != ProtocolConformanceKind::Specialized);
}
void SpecializedProtocolConformance::computeConditionalRequirements() const {
// already computed?
if (ConditionalRequirements)
return;
auto parentCondReqs =
GenericConformance->getConditionalRequirementsIfAvailable();
if (!parentCondReqs)
return;
if (!parentCondReqs->empty()) {
// Substitute the conditional requirements so that they're phrased in
// terms of the specialized types, not the conformance-declaring decl's
// types.
auto nominal = GenericConformance->getType()->getAnyNominal();
auto module = nominal->getModuleContext();
auto subMap = getType()->getContextSubstitutionMap(module, nominal);
SmallVector<Requirement, 4> newReqs;
for (auto oldReq : *parentCondReqs) {
if (auto newReq = oldReq.subst(QuerySubstitutionMap{subMap},
LookUpConformanceInModule(module)))
newReqs.push_back(*newReq);
}
auto &ctxt = getProtocol()->getASTContext();
ConditionalRequirements = ctxt.AllocateCopy(newReqs);
} else {
ConditionalRequirements = ArrayRef<Requirement>();
}
}
bool SpecializedProtocolConformance::hasTypeWitness(
AssociatedTypeDecl *assocType) const {
return TypeWitnesses.find(assocType) != TypeWitnesses.end() ||
GenericConformance->hasTypeWitness(assocType);
}
TypeWitnessAndDecl
SpecializedProtocolConformance::getTypeWitnessAndDecl(
AssociatedTypeDecl *assocType,
SubstOptions options) const {
assert(getProtocol() == cast<ProtocolDecl>(assocType->getDeclContext()) &&
"associated type in wrong protocol");
// If we've already created this type witness, return it.
auto known = TypeWitnesses.find(assocType);
if (known != TypeWitnesses.end()) {
return known->second;
}
// Otherwise, perform substitutions to create this witness now.
// Local function to determine whether we will end up referring to a
// tentative witness that may not be chosen.
auto root = GenericConformance->getRootConformance();
auto isTentativeWitness = [&] {
if (root->getState() != ProtocolConformanceState::CheckingTypeWitnesses)
return false;
return !root->hasTypeWitness(assocType);
};
auto genericWitnessAndDecl
= GenericConformance->getTypeWitnessAndDecl(assocType, options);
auto genericWitness = genericWitnessAndDecl.getWitnessType();
if (!genericWitness)
return { Type(), nullptr };
auto *typeDecl = genericWitnessAndDecl.getWitnessDecl();
// Form the substitution.
auto substitutionMap = getSubstitutionMap();
if (substitutionMap.empty())
return TypeWitnessAndDecl();
// Apply the substitution we computed above
auto specializedType = genericWitness.subst(substitutionMap, options);
if (specializedType->hasError()) {
if (isTentativeWitness())
return { Type(), nullptr };
specializedType = ErrorType::get(genericWitness);
}
// If we aren't in a case where we used the tentative type witness
// information, cache the result.
auto specializedWitnessAndDecl = TypeWitnessAndDecl{specializedType, typeDecl};
if (!isTentativeWitness() && !specializedType->hasError())
TypeWitnesses[assocType] = specializedWitnessAndDecl;
return specializedWitnessAndDecl;
}
ProtocolConformanceRef
SpecializedProtocolConformance::getAssociatedConformance(Type assocType,
ProtocolDecl *protocol) const {
ProtocolConformanceRef conformance =
GenericConformance->getAssociatedConformance(assocType, protocol);
auto subMap = getSubstitutionMap();
Type origType =
(conformance.isConcrete()
? conformance.getConcrete()->getType()
: GenericConformance->getAssociatedType(assocType));
return conformance.subst(origType, subMap);
}
ConcreteDeclRef
SpecializedProtocolConformance::getWitnessDeclRef(
ValueDecl *requirement) const {
auto baseWitness = GenericConformance->getWitnessDeclRef(requirement);
if (!baseWitness || !baseWitness.isSpecialized())
return baseWitness;
auto specializationMap = getSubstitutionMap();
auto witnessDecl = baseWitness.getDecl();
auto witnessMap = baseWitness.getSubstitutions();
auto combinedMap = witnessMap.subst(specializationMap);
return ConcreteDeclRef(witnessDecl, combinedMap);
}
ProtocolConformanceRef
InheritedProtocolConformance::getAssociatedConformance(Type assocType,
ProtocolDecl *protocol) const {
auto underlying =
InheritedConformance->getAssociatedConformance(assocType, protocol);
// If the conformance is for Self, return an inherited conformance.
if (underlying.isConcrete() &&
assocType->isEqual(getProtocol()->getSelfInterfaceType())) {
auto subclassType = getType();
ASTContext &ctx = subclassType->getASTContext();
return ProtocolConformanceRef(
ctx.getInheritedConformance(subclassType,
underlying.getConcrete()));
}
return underlying;
}
ConcreteDeclRef
InheritedProtocolConformance::getWitnessDeclRef(ValueDecl *requirement) const {
// FIXME: substitutions?
return InheritedConformance->getWitnessDeclRef(requirement);
}
const NormalProtocolConformance *
ProtocolConformance::getRootNormalConformance() const {
// This is an unsafe cast; remove this entire method.
return cast<NormalProtocolConformance>(getRootConformance());
}
const RootProtocolConformance *
ProtocolConformance::getRootConformance() const {
const ProtocolConformance *C = this;
while (true) {
switch (C->getKind()) {
case ProtocolConformanceKind::Normal:
case ProtocolConformanceKind::Self:
case ProtocolConformanceKind::Builtin:
return cast<RootProtocolConformance>(C);
case ProtocolConformanceKind::Inherited:
C = cast<InheritedProtocolConformance>(C)
->getInheritedConformance();
break;
case ProtocolConformanceKind::Specialized:
C = cast<SpecializedProtocolConformance>(C)
->getGenericConformance();
break;
}
}
}
bool ProtocolConformance::isVisibleFrom(const DeclContext *dc) const {
// FIXME: Implement me!
return true;
}
ProtocolConformance *
ProtocolConformance::subst(SubstitutionMap subMap,
SubstOptions options) const {
return subst(QuerySubstitutionMap{subMap},
LookUpConformanceInSubstitutionMap(subMap),
options);
}
ProtocolConformance *
ProtocolConformance::subst(TypeSubstitutionFn subs,
LookupConformanceFn conformances,
SubstOptions options) const {
switch (getKind()) {
case ProtocolConformanceKind::Normal: {
auto origType = getType();
if (!origType->hasTypeParameter() &&
!origType->hasArchetype())
return const_cast<ProtocolConformance *>(this);
auto substType = origType.subst(subs, conformances, options);
if (substType->isEqual(origType))
return const_cast<ProtocolConformance *>(this);
auto subMap = SubstitutionMap::get(getGenericSignature(),
subs, conformances);
return substType->getASTContext()
.getSpecializedConformance(substType,
const_cast<ProtocolConformance *>(this),
subMap);
}
case ProtocolConformanceKind::Self:
case ProtocolConformanceKind::Builtin:
return const_cast<ProtocolConformance*>(this);
case ProtocolConformanceKind::Inherited: {
// Substitute the base.
auto inheritedConformance
= cast<InheritedProtocolConformance>(this)->getInheritedConformance();
auto origType = getType();
if (!origType->hasTypeParameter() &&
!origType->hasArchetype()) {
return const_cast<ProtocolConformance *>(this);
}
auto origBaseType = inheritedConformance->getType();
if (origBaseType->hasTypeParameter() ||
origBaseType->hasArchetype()) {
// Substitute into the superclass.
inheritedConformance = inheritedConformance->subst(subs, conformances,
options);
}
auto substType = origType.subst(subs, conformances, options);
return substType->getASTContext()
.getInheritedConformance(substType, inheritedConformance);
}
case ProtocolConformanceKind::Specialized: {
// Substitute the substitutions in the specialized conformance.
auto spec = cast<SpecializedProtocolConformance>(this);
auto genericConformance = spec->getGenericConformance();
auto subMap = spec->getSubstitutionMap();
auto origType = getType();
auto substType = origType.subst(subs, conformances, options);
return substType->getASTContext()
.getSpecializedConformance(substType, genericConformance,
subMap.subst(subs, conformances, options));
}
}
llvm_unreachable("bad ProtocolConformanceKind");
}
ProtocolConformance *
ProtocolConformance::getInheritedConformance(ProtocolDecl *protocol) const {
auto result =
getAssociatedConformance(getProtocol()->getSelfInterfaceType(), protocol);
return result.isConcrete() ? result.getConcrete() : nullptr;
}
#pragma mark Protocol conformance lookup
void NominalTypeDecl::prepareConformanceTable() const {
if (ConformanceTable)
return;
auto mutableThis = const_cast<NominalTypeDecl *>(this);
ASTContext &ctx = getASTContext();
ConformanceTable = new (ctx) ConformanceLookupTable(ctx);
++NumConformanceLookupTables;
// If this type declaration was not parsed from source code or introduced
// via the Clang importer, don't add any synthesized conformances.
auto *file = cast<FileUnit>(getModuleScopeContext());
if (file->getKind() != FileUnitKind::Source &&
file->getKind() != FileUnitKind::ClangModule &&
file->getKind() != FileUnitKind::DWARFModule) {
return;
}
SmallPtrSet<ProtocolDecl *, 2> protocols;
auto addSynthesized = [&](KnownProtocolKind kind) {
if (auto *proto = getASTContext().getProtocol(kind)) {
if (protocols.count(proto) == 0) {
ConformanceTable->addSynthesizedConformance(mutableThis, proto);
protocols.insert(proto);
}
}
};
// Add protocols for any synthesized protocol attributes.
for (auto attr : getAttrs().getAttributes<SynthesizedProtocolAttr>()) {
addSynthesized(attr->getProtocolKind());
}
// Add any implicit conformances.
if (auto theEnum = dyn_cast<EnumDecl>(mutableThis)) {
if (theEnum->hasCases() && theEnum->hasOnlyCasesWithoutAssociatedValues()) {
// Simple enumerations conform to Equatable.
addSynthesized(KnownProtocolKind::Equatable);
// Simple enumerations conform to Hashable.
addSynthesized(KnownProtocolKind::Hashable);
}
// Enumerations with a raw type conform to RawRepresentable.
if (theEnum->hasRawType() && !theEnum->getRawType()->hasError()) {
addSynthesized(KnownProtocolKind::RawRepresentable);
}
}
// Actor classes conform to the actor protocol.
if (auto classDecl = dyn_cast<ClassDecl>(mutableThis)) {
if (classDecl->isDistributedActor())
addSynthesized(KnownProtocolKind::DistributedActor);
else if (classDecl->isActor())
addSynthesized(KnownProtocolKind::Actor);
}
// Global actors conform to the GlobalActor protocol.
if (mutableThis->getAttrs().hasAttribute<GlobalActorAttr>()) {
addSynthesized(KnownProtocolKind::GlobalActor);
}
}
bool NominalTypeDecl::lookupConformance(
ModuleDecl *module, ProtocolDecl *protocol,
SmallVectorImpl<ProtocolConformance *> &conformances) const {
prepareConformanceTable();
return ConformanceTable->lookupConformance(
module,
const_cast<NominalTypeDecl *>(this),
protocol,
conformances);
}
SmallVector<ProtocolDecl *, 2> NominalTypeDecl::getAllProtocols() const {
prepareConformanceTable();
SmallVector<ProtocolDecl *, 2> result;
ConformanceTable->getAllProtocols(const_cast<NominalTypeDecl *>(this),
result);
return result;
}
SmallVector<ProtocolConformance *, 2> NominalTypeDecl::getAllConformances(
bool sorted) const
{
prepareConformanceTable();
SmallVector<ProtocolConformance *, 2> result;
ConformanceTable->getAllConformances(const_cast<NominalTypeDecl *>(this),
sorted,
result);
return result;
}
void NominalTypeDecl::getImplicitProtocols(
SmallVectorImpl<ProtocolDecl *> &protocols) {
prepareConformanceTable();
ConformanceTable->getImplicitProtocols(this, protocols);
}
void NominalTypeDecl::registerProtocolConformance(
ProtocolConformance *conformance) {
prepareConformanceTable();
ConformanceTable->registerProtocolConformance(conformance);
}
ArrayRef<ValueDecl *>
NominalTypeDecl::getSatisfiedProtocolRequirementsForMember(
const ValueDecl *member,
bool sorted) const {
assert(member->getDeclContext()->getSelfNominalTypeDecl() == this);
assert(!isa<ProtocolDecl>(this));
prepareConformanceTable();
return ConformanceTable->getSatisfiedProtocolRequirementsForMember(member,
const_cast<NominalTypeDecl *>(this),
sorted);
}
SmallVector<ProtocolDecl *, 2>
IterableDeclContext::getLocalProtocols(ConformanceLookupKind lookupKind) const {
SmallVector<ProtocolDecl *, 2> result;
for (auto conformance : getLocalConformances(lookupKind))
result.push_back(conformance->getProtocol());
return result;
}
/// Find a synthesized Sendable conformance in this declaration context,
/// if there is one.
static ProtocolConformance *findSynthesizedSendableConformance(
const DeclContext *dc) {
auto nominal = dc->getSelfNominalTypeDecl();
if (!nominal)
return nullptr;
if (isa<ProtocolDecl>(nominal))
return nullptr;
if (dc->getParentModule() != nominal->getParentModule())
return nullptr;
auto cvProto = nominal->getASTContext().getProtocol(
KnownProtocolKind::Sendable);
if (!cvProto)
return nullptr;
auto conformance = dc->getParentModule()->lookupConformance(
nominal->getDeclaredInterfaceType(), cvProto);
if (!conformance || !conformance.isConcrete())
return nullptr;
auto concrete = conformance.getConcrete();
if (concrete->getDeclContext() != dc)
return nullptr;
if (isa<InheritedProtocolConformance>(concrete))
return nullptr;
auto normal = concrete->getRootNormalConformance();
if (!normal || normal->getSourceKind() != ConformanceEntryKind::Synthesized)
return nullptr;
return normal;
}
std::vector<ProtocolConformance *>
LookupAllConformancesInContextRequest::evaluate(
Evaluator &eval, const IterableDeclContext *IDC) const {
// Dig out the nominal type.
const auto dc = IDC->getAsGenericContext();
const auto nominal = dc->getSelfNominalTypeDecl();
if (!nominal) {
return { };
}
// Protocols only have self-conformances.
if (auto protocol = dyn_cast<ProtocolDecl>(nominal)) {
if (protocol->requiresSelfConformanceWitnessTable()) {
return { protocol->getASTContext().getSelfConformance(protocol) };
}
return { };
}
// Record all potential conformances.
nominal->prepareConformanceTable();
std::vector<ProtocolConformance *> conformances;
nominal->ConformanceTable->lookupConformances(
nominal,
const_cast<GenericContext *>(dc),
&conformances,
nullptr);
return conformances;
}
SmallVector<ProtocolConformance *, 2>
IterableDeclContext::getLocalConformances(ConformanceLookupKind lookupKind)
const {
// Look up the cached set of all of the conformances.
std::vector<ProtocolConformance *> conformances =
evaluateOrDefault(
getASTContext().evaluator, LookupAllConformancesInContextRequest{this},
{ });
// Copy all of the conformances we want.
SmallVector<ProtocolConformance *, 2> result;
std::copy_if(
conformances.begin(), conformances.end(), std::back_inserter(result),
[&](ProtocolConformance *conformance) {
// If we are to filter out this result, do so now.
switch (lookupKind) {
case ConformanceLookupKind::OnlyExplicit:
switch (conformance->getSourceKind()) {
case ConformanceEntryKind::Explicit:
case ConformanceEntryKind::Synthesized:
return true;
case ConformanceEntryKind::Implied:
case ConformanceEntryKind::Inherited:
return false;
}
case ConformanceLookupKind::NonInherited:
switch (conformance->getSourceKind()) {
case ConformanceEntryKind::Explicit:
case ConformanceEntryKind::Synthesized:
case ConformanceEntryKind::Implied:
return true;
case ConformanceEntryKind::Inherited:
return false;
}
case ConformanceLookupKind::All:
case ConformanceLookupKind::NonStructural:
return true;
}
});
// If we want to add structural conformances, do so now.
switch (lookupKind) {
case ConformanceLookupKind::All:
case ConformanceLookupKind::NonInherited: {
// Look for a Sendable conformance globally. If it is synthesized
// and matches this declaration context, use it.
auto dc = getAsGenericContext();
if (auto conformance = findSynthesizedSendableConformance(dc))
result.push_back(conformance);
break;
}
case ConformanceLookupKind::NonStructural:
case ConformanceLookupKind::OnlyExplicit:
break;
}
return result;
}
SmallVector<ConformanceDiagnostic, 4>
IterableDeclContext::takeConformanceDiagnostics() const {
SmallVector<ConformanceDiagnostic, 4> result;
// Dig out the nominal type.
const auto dc = getAsGenericContext();
const auto nominal = dc->getSelfNominalTypeDecl();
if (!nominal) {
return result;
}
// Protocols are not subject to the checks for supersession.
if (isa<ProtocolDecl>(nominal)) {
return result;
}
// Update to record all potential conformances.
nominal->prepareConformanceTable();
nominal->ConformanceTable->lookupConformances(
nominal,
const_cast<GenericContext *>(dc),
nullptr,
&result);
return result;
}
/// Check of all types used by the conformance are canonical.
bool ProtocolConformance::isCanonical() const {
// Normal conformances are always canonical by construction.
if (getKind() == ProtocolConformanceKind::Normal)
return true;
if (!getType()->isCanonical())
return false;
switch (getKind()) {
case ProtocolConformanceKind::Self:
case ProtocolConformanceKind::Normal:
case ProtocolConformanceKind::Builtin: {
return true;
}
case ProtocolConformanceKind::Inherited: {
// Substitute the base.
auto inheritedConformance
= cast<InheritedProtocolConformance>(this);
return inheritedConformance->getInheritedConformance()->isCanonical();
}
case ProtocolConformanceKind::Specialized: {
// Substitute the substitutions in the specialized conformance.
auto spec = cast<SpecializedProtocolConformance>(this);
auto genericConformance = spec->getGenericConformance();
if (!genericConformance->isCanonical())
return false;
if (!spec->getSubstitutionMap().isCanonical()) return false;
return true;
}
}
llvm_unreachable("bad ProtocolConformanceKind");
}
/// Check of all types used by the conformance are canonical.
ProtocolConformance *ProtocolConformance::getCanonicalConformance() {
if (isCanonical())
return this;
switch (getKind()) {
case ProtocolConformanceKind::Self:
case ProtocolConformanceKind::Normal:
case ProtocolConformanceKind::Builtin: {
// Root conformances are always canonical by construction.
return this;
}
case ProtocolConformanceKind::Inherited: {
auto &Ctx = getType()->getASTContext();
auto inheritedConformance = cast<InheritedProtocolConformance>(this);
return Ctx.getInheritedConformance(
getType()->getCanonicalType(),
inheritedConformance->getInheritedConformance()
->getCanonicalConformance());
}
case ProtocolConformanceKind::Specialized: {
auto &Ctx = getType()->getASTContext();
// Substitute the substitutions in the specialized conformance.
auto spec = cast<SpecializedProtocolConformance>(this);
auto genericConformance = spec->getGenericConformance();
return Ctx.getSpecializedConformance(
getType()->getCanonicalType(),
genericConformance->getCanonicalConformance(),
spec->getSubstitutionMap().getCanonical());
}
}
llvm_unreachable("bad ProtocolConformanceKind");
}
/// Check of all types used by the conformance are canonical.
bool ProtocolConformanceRef::isCanonical() const {
if (isAbstract() || isInvalid())
return true;
return getConcrete()->isCanonical();
}
ProtocolConformanceRef
ProtocolConformanceRef::getCanonicalConformanceRef() const {
if (isAbstract() || isInvalid())
return *this;
return ProtocolConformanceRef(getConcrete()->getCanonicalConformance());
}
BuiltinProtocolConformance::BuiltinProtocolConformance(
Type conformingType, ProtocolDecl *protocol,
GenericSignature genericSig,
ArrayRef<Requirement> conditionalRequirements
) : RootProtocolConformance(ProtocolConformanceKind::Builtin, conformingType),
protocol(protocol), genericSig(genericSig),
numConditionalRequirements(conditionalRequirements.size()) {
std::uninitialized_copy(conditionalRequirements.begin(),
conditionalRequirements.end(),
getTrailingObjects<Requirement>());
}
// See swift/Basic/Statistic.h for declaration: this enables tracing
// ProtocolConformances, is defined here to avoid too much layering violation /
// circular linkage dependency.
struct ProtocolConformanceTraceFormatter
: public UnifiedStatsReporter::TraceFormatter {
void traceName(const void *Entity, raw_ostream &OS) const override {
if (!Entity)
return;
const ProtocolConformance *C =
static_cast<const ProtocolConformance *>(Entity);
C->printName(OS);
}
void traceLoc(const void *Entity, SourceManager *SM,
clang::SourceManager *CSM, raw_ostream &OS) const override {
if (!Entity)
return;
const ProtocolConformance *C =
static_cast<const ProtocolConformance *>(Entity);
if (auto const *NPC = dyn_cast<NormalProtocolConformance>(C)) {
NPC->getLoc().print(OS, *SM);
} else if (auto const *DC = C->getDeclContext()) {
if (auto const *D = DC->getAsDecl())
D->getLoc().print(OS, *SM);
}
}
};
static ProtocolConformanceTraceFormatter TF;
template<>
const UnifiedStatsReporter::TraceFormatter*
FrontendStatsTracer::getTraceFormatter<const ProtocolConformance *>() {
return &TF;
}
void swift::simple_display(llvm::raw_ostream &out,
const ProtocolConformance *conf) {
conf->printName(out);
}
SourceLoc swift::extractNearestSourceLoc(const ProtocolConformance *conformance) {
return extractNearestSourceLoc(conformance->getDeclContext());
}
void swift::simple_display(llvm::raw_ostream &out, ProtocolConformanceRef conformanceRef) {
if (conformanceRef.isAbstract()) {
simple_display(out, conformanceRef.getAbstract());
} else if (conformanceRef.isConcrete()) {
simple_display(out, conformanceRef.getConcrete());
}
}
SourceLoc swift::extractNearestSourceLoc(const ProtocolConformanceRef conformanceRef) {
if (conformanceRef.isAbstract()) {
return extractNearestSourceLoc(conformanceRef.getAbstract());
} else if (conformanceRef.isConcrete()) {
return extractNearestSourceLoc(conformanceRef.getConcrete());
}
return SourceLoc();
}