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fuchsia / third_party / swift / f2cf0510d6e25911e9babada46e0025862bd00cd / . / lib / AST / NameLookup.cpp
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//===--- NameLookup.cpp - Swift Name Lookup Routines ----------------------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2018 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 interfaces for performing name lookup.
//
//===----------------------------------------------------------------------===//
#include "swift/AST/NameLookup.h"
#include "swift/AST/ASTContext.h"
#include "swift/AST/ASTVisitor.h"
#include "swift/AST/ClangModuleLoader.h"
#include "swift/AST/DebuggerClient.h"
#include "swift/AST/ExistentialLayout.h"
#include "swift/AST/GenericParamList.h"
#include "swift/AST/GenericSignature.h"
#include "swift/AST/ImportCache.h"
#include "swift/AST/Initializer.h"
#include "swift/AST/LazyResolver.h"
#include "swift/AST/ModuleNameLookup.h"
#include "swift/AST/NameLookupRequests.h"
#include "swift/AST/ParameterList.h"
#include "swift/AST/SourceFile.h"
#include "swift/Basic/Debug.h"
#include "swift/Basic/STLExtras.h"
#include "swift/Basic/SourceManager.h"
#include "swift/Basic/Statistic.h"
#include "swift/Parse/Lexer.h"
#include "clang/AST/DeclObjC.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/TinyPtrVector.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#define DEBUG_TYPE "namelookup"
using namespace swift;
using namespace swift::namelookup;
void VisibleDeclConsumer::anchor() {}
void VectorDeclConsumer::anchor() {}
ValueDecl *LookupResultEntry::getBaseDecl() const {
if (BaseDC == nullptr)
return nullptr;
if (auto *AFD = dyn_cast<AbstractFunctionDecl>(BaseDC))
return AFD->getImplicitSelfDecl();
if (auto *PBI = dyn_cast<PatternBindingInitializer>(BaseDC)) {
auto *selfDecl = PBI->getImplicitSelfDecl();
assert(selfDecl);
return selfDecl;
}
if (auto *CE = dyn_cast<ClosureExpr>(BaseDC)) {
auto *selfDecl = CE->getCapturedSelfDecl();
assert(selfDecl);
assert(selfDecl->isSelfParamCapture());
return selfDecl;
}
auto *nominalDecl = BaseDC->getSelfNominalTypeDecl();
assert(nominalDecl);
return nominalDecl;
}
void LookupResult::filter(
llvm::function_ref<bool(LookupResultEntry, bool)> pred) {
size_t index = 0;
size_t originalFirstOuter = IndexOfFirstOuterResult;
Results.erase(std::remove_if(Results.begin(), Results.end(),
[&](LookupResultEntry result) -> bool {
auto isInner = index < originalFirstOuter;
++index;
if (pred(result, !isInner))
return false;
// Need to remove this, which means, if it is
// an inner result, the outer results need to
// shift down.
if (isInner)
--IndexOfFirstOuterResult;
return true;
}),
Results.end());
}
void LookupResult::shiftDownResults() {
// Remove inner results.
Results.erase(Results.begin(), Results.begin() + IndexOfFirstOuterResult);
IndexOfFirstOuterResult = 0;
if (Results.empty())
return;
// Compute IndexOfFirstOuterResult.
const DeclContext *dcInner = Results.front().getValueDecl()->getDeclContext();
for (auto &&result : Results) {
const DeclContext *dc = result.getValueDecl()->getDeclContext();
if (dc == dcInner ||
(dc->isModuleScopeContext() && dcInner->isModuleScopeContext()))
++IndexOfFirstOuterResult;
else
break;
}
}
void swift::simple_display(llvm::raw_ostream &out,
UnqualifiedLookupOptions options) {
using Flag = std::pair<UnqualifiedLookupFlags, StringRef>;
Flag possibleFlags[] = {
{UnqualifiedLookupFlags::AllowProtocolMembers, "AllowProtocolMembers"},
{UnqualifiedLookupFlags::IgnoreAccessControl, "IgnoreAccessControl"},
{UnqualifiedLookupFlags::IncludeOuterResults, "IncludeOuterResults"},
{UnqualifiedLookupFlags::TypeLookup, "TypeLookup"},
};
auto flagsToPrint = llvm::make_filter_range(
possibleFlags, [&](Flag flag) { return options.contains(flag.first); });
out << "{ ";
interleave(
flagsToPrint, [&](Flag flag) { out << flag.second; },
[&] { out << ", "; });
out << " }";
}
void DebuggerClient::anchor() {}
void AccessFilteringDeclConsumer::foundDecl(
ValueDecl *D, DeclVisibilityKind reason,
DynamicLookupInfo dynamicLookupInfo) {
if (!D->isAccessibleFrom(DC))
return;
ChainedConsumer.foundDecl(D, reason, dynamicLookupInfo);
}
void UsableFilteringDeclConsumer::foundDecl(ValueDecl *D,
DeclVisibilityKind reason, DynamicLookupInfo dynamicLookupInfo) {
// Skip when Loc is within the decl's own initializer
if (auto *VD = dyn_cast<VarDecl>(D)) {
Expr *init = VD->getParentInitializer();
if (auto *PD = dyn_cast<ParamDecl>(D)) {
init = PD->getStructuralDefaultExpr();
}
// Only check if the VarDecl has the same (or parent) context to avoid
// grabbing the end location for every decl with an initializer
if (init != nullptr) {
auto *varContext = VD->getDeclContext();
if (DC == varContext || DC->isChildContextOf(varContext)) {
auto initRange = Lexer::getCharSourceRangeFromSourceRange(
SM, init->getSourceRange());
if (initRange.isValid() && initRange.contains(Loc))
return;
}
}
}
switch (reason) {
case DeclVisibilityKind::LocalVariable:
// Skip if Loc is before the found decl, unless its a TypeDecl (whose use
// before its declaration is still allowed)
if (!isa<TypeDecl>(D) && !SM.isBeforeInBuffer(D->getLoc(), Loc))
return;
break;
default:
// The rest of the file is currently skipped, so no need to check
// decl location for VisibleAtTopLevel. Other visibility kinds are always
// usable
break;
}
ChainedConsumer.foundDecl(D, reason, dynamicLookupInfo);
}
void LookupResultEntry::print(llvm::raw_ostream& out) const {
getValueDecl()->print(out);
if (auto dc = getBaseDecl()) {
out << "\nbase: ";
dc->print(out);
out << "\n";
} else
out << "\n(no-base)\n";
}
bool swift::removeOverriddenDecls(SmallVectorImpl<ValueDecl*> &decls) {
if (decls.size() < 2)
return false;
llvm::SmallPtrSet<ValueDecl*, 8> overridden;
for (auto decl : decls) {
// Don't look at the overrides of operators in protocols. The global
// lookup of operators means that we can find overriding operators that
// aren't relevant to the types in hand, and will fail to type check.
if (isa<ProtocolDecl>(decl->getDeclContext())) {
if (auto func = dyn_cast<FuncDecl>(decl))
if (func->isOperator())
continue;
}
while (auto overrides = decl->getOverriddenDecl()) {
overridden.insert(overrides);
// Because initializers from Objective-C base classes have greater
// visibility than initializers written in Swift classes, we can
// have a "break" in the set of declarations we found, where
// C.init overrides B.init overrides A.init, but only C.init and
// A.init are in the chain. Make sure we still remove A.init from the
// set in this case.
if (decl->getBaseName() == DeclBaseName::createConstructor()) {
/// FIXME: Avoid the possibility of an infinite loop by fixing the root
/// cause instead (incomplete circularity detection).
assert(decl != overrides && "Circular class inheritance?");
decl = overrides;
continue;
}
break;
}
}
// If no methods were overridden, we're done.
if (overridden.empty()) return false;
// Erase any overridden declarations
bool anyOverridden = false;
decls.erase(std::remove_if(decls.begin(), decls.end(),
[&](ValueDecl *decl) -> bool {
if (overridden.count(decl) > 0) {
anyOverridden = true;
return true;
}
return false;
}),
decls.end());
return anyOverridden;
}
enum class ConstructorComparison {
Worse,
Same,
Better,
};
/// Determines whether \p ctor1 is a "better" initializer than \p ctor2.
static ConstructorComparison compareConstructors(ConstructorDecl *ctor1,
ConstructorDecl *ctor2,
const swift::ASTContext &ctx) {
bool available1 = !ctor1->getAttrs().isUnavailable(ctx);
bool available2 = !ctor2->getAttrs().isUnavailable(ctx);
// An unavailable initializer is always worse than an available initializer.
if (available1 < available2)
return ConstructorComparison::Worse;
if (available1 > available2)
return ConstructorComparison::Better;
CtorInitializerKind kind1 = ctor1->getInitKind();
CtorInitializerKind kind2 = ctor2->getInitKind();
if (kind1 > kind2)
return ConstructorComparison::Worse;
if (kind1 < kind2)
return ConstructorComparison::Better;
return ConstructorComparison::Same;
}
/// Given a set of declarations whose names and interface types have matched,
/// figure out which of these declarations have been shadowed by others.
template <typename T>
static void recordShadowedDeclsAfterTypeMatch(
ArrayRef<T> decls,
const DeclContext *dc,
llvm::SmallPtrSetImpl<T> &shadowed) {
assert(decls.size() > 1 && "Nothing collided");
// Compare each declaration to every other declaration. This is
// unavoidably O(n^2) in the number of declarations, but because they
// all have the same signature, we expect n to remain small.
auto *curModule = dc->getParentModule();
ASTContext &ctx = curModule->getASTContext();
auto &imports = ctx.getImportCache();
for (unsigned firstIdx : indices(decls)) {
auto firstDecl = decls[firstIdx];
auto firstModule = firstDecl->getModuleContext();
bool firstTopLevel = firstDecl->getDeclContext()->isModuleScopeContext();
auto name = firstDecl->getBaseName();
auto isShadowed = [&](ArrayRef<ImportPath::Access> paths) {
for (auto path : paths) {
if (path.matches(name))
return false;
}
return true;
};
auto isScopedImport = [&](ArrayRef<ImportPath::Access> paths) {
for (auto path : paths) {
if (path.empty())
continue;
if (path.matches(name))
return true;
}
return false;
};
auto isPrivateImport = [&](ModuleDecl *module) {
auto file = dc->getParentSourceFile();
if (!file) return false;
for (const auto &import : file->getImports()) {
if (import.options.contains(ImportFlags::PrivateImport)
&& import.module.importedModule == module
&& import.module.accessPath.matches(name))
return true;
}
return false;
};
bool firstPrivate = isPrivateImport(firstModule);
for (unsigned secondIdx : range(firstIdx + 1, decls.size())) {
// Determine whether one module takes precedence over another.
auto secondDecl = decls[secondIdx];
auto secondModule = secondDecl->getModuleContext();
bool secondTopLevel = secondDecl->getDeclContext()->isModuleScopeContext();
bool secondPrivate = isPrivateImport(secondModule);
// For member types, we skip most of the below rules. Instead, we allow
// member types defined in a subclass to shadow member types defined in
// a superclass.
if (isa<TypeDecl>(firstDecl) &&
isa<TypeDecl>(secondDecl) &&
!firstTopLevel &&
!secondTopLevel) {
auto *firstClass = firstDecl->getDeclContext()->getSelfClassDecl();
auto *secondClass = secondDecl->getDeclContext()->getSelfClassDecl();
if (firstClass && secondClass && firstClass != secondClass) {
if (firstClass->isSuperclassOf(secondClass)) {
shadowed.insert(firstDecl);
continue;
} else if (secondClass->isSuperclassOf(firstClass)) {
shadowed.insert(secondDecl);
continue;
}
}
// If one declaration is in a protocol or extension thereof and the
// other is not, prefer the one that is not.
if ((bool)firstDecl->getDeclContext()->getSelfProtocolDecl() !=
(bool)secondDecl->getDeclContext()->getSelfProtocolDecl()) {
if (firstDecl->getDeclContext()->getSelfProtocolDecl()) {
shadowed.insert(firstDecl);
break;
} else {
shadowed.insert(secondDecl);
continue;
}
}
continue;
}
// Top-level type declarations in a module shadow other declarations
// visible through the module's imports.
//
// [Backward compatibility] Note that members of types have the same
// shadowing check, but we do it after dropping unavailable members.
if (firstModule != secondModule &&
firstTopLevel && secondTopLevel) {
auto firstPaths = imports.getAllAccessPathsNotShadowedBy(
firstModule, secondModule, dc);
auto secondPaths = imports.getAllAccessPathsNotShadowedBy(
secondModule, firstModule, dc);
// Check if one module shadows the other.
if (isShadowed(firstPaths)) {
shadowed.insert(firstDecl);
break;
} else if (isShadowed(secondPaths)) {
shadowed.insert(secondDecl);
continue;
}
// If neither module shadows the other, but one was imported with
// '@_private import' in dc, we want to favor that module. This makes
// name lookup in this file behave more like name lookup in the file we
// imported from, avoiding headaches for source-transforming tools.
if (!firstPrivate && secondPrivate) {
shadowed.insert(firstDecl);
break;
} else if (firstPrivate && !secondPrivate) {
shadowed.insert(secondDecl);
continue;
}
// We might be in a situation where neither module shadows the
// other, but one declaration is visible via a scoped import.
bool firstScoped = isScopedImport(firstPaths);
bool secondScoped = isScopedImport(secondPaths);
if (!firstScoped && secondScoped) {
shadowed.insert(firstDecl);
break;
} else if (firstScoped && !secondScoped) {
shadowed.insert(secondDecl);
continue;
}
}
// Swift 4 compatibility hack: Don't shadow properties defined in
// extensions of generic types with properties defined elsewhere.
// This is due to the fact that in Swift 4, we only gave custom overload
// types to properties in extensions of generic types, otherwise we
// used the null type.
if (!ctx.isSwiftVersionAtLeast(5) && isa<ValueDecl>(firstDecl)) {
auto secondSig = cast<ValueDecl>(secondDecl)->getOverloadSignature();
auto firstSig = cast<ValueDecl>(firstDecl)->getOverloadSignature();
if (firstSig.IsVariable && secondSig.IsVariable)
if (firstSig.InExtensionOfGenericType !=
secondSig.InExtensionOfGenericType)
continue;
}
// If one declaration is in a protocol or extension thereof and the
// other is not, prefer the one that is not.
if ((bool)firstDecl->getDeclContext()->getSelfProtocolDecl() !=
(bool)secondDecl->getDeclContext()->getSelfProtocolDecl()) {
if (firstDecl->getDeclContext()->getSelfProtocolDecl()) {
shadowed.insert(firstDecl);
break;
} else {
shadowed.insert(secondDecl);
continue;
}
}
// If one declaration is available and the other is not, prefer the
// available one.
if (firstDecl->getAttrs().isUnavailable(ctx) !=
secondDecl->getAttrs().isUnavailable(ctx)) {
if (firstDecl->getAttrs().isUnavailable(ctx)) {
shadowed.insert(firstDecl);
break;
} else {
shadowed.insert(secondDecl);
continue;
}
}
// Don't apply module-shadowing rules to members of protocol types.
if (isa<ProtocolDecl>(firstDecl->getDeclContext()) ||
isa<ProtocolDecl>(secondDecl->getDeclContext()))
continue;
// [Backward compatibility] For members of types, the general module
// shadowing check is performed after unavailable candidates have
// already been dropped.
if (firstModule != secondModule &&
!firstTopLevel && !secondTopLevel) {
auto firstPaths = imports.getAllAccessPathsNotShadowedBy(
firstModule, secondModule, dc);
auto secondPaths = imports.getAllAccessPathsNotShadowedBy(
secondModule, firstModule, dc);
// Check if one module shadows the other.
if (isShadowed(firstPaths)) {
shadowed.insert(firstDecl);
break;
} else if (isShadowed(secondPaths)) {
shadowed.insert(secondDecl);
continue;
}
}
// Prefer declarations in the any module over those in the standard
// library module.
if (auto swiftModule = ctx.getStdlibModule()) {
if ((firstModule == swiftModule) != (secondModule == swiftModule)) {
// If the second module is the standard library module, the second
// declaration is shadowed by the first.
if (secondModule == swiftModule) {
shadowed.insert(secondDecl);
continue;
}
// Otherwise, the first declaration is shadowed by the second. There is
// no point in continuing to compare the first declaration to others.
shadowed.insert(firstDecl);
break;
}
}
// Next, prefer any other module over the _Concurrency module.
if (auto concurModule = ctx.getLoadedModule(ctx.Id_Concurrency)) {
if ((firstModule == concurModule) != (secondModule == concurModule)) {
// If second module is _Concurrency, then it is shadowed by first.
if (secondModule == concurModule) {
shadowed.insert(secondDecl);
continue;
}
// Otherwise, the first declaration is shadowed by the second.
shadowed.insert(firstDecl);
break;
}
}
// The Foundation overlay introduced Data.withUnsafeBytes, which is
// treated as being ambiguous with SwiftNIO's Data.withUnsafeBytes
// extension. Apply a special-case name shadowing rule to use the
// latter rather than the former, which be the consequence of a more
// significant change to name shadowing in the future.
if (auto owningStruct1
= firstDecl->getDeclContext()->getSelfStructDecl()) {
if (auto owningStruct2
= secondDecl->getDeclContext()->getSelfStructDecl()) {
if (owningStruct1 == owningStruct2 &&
owningStruct1->getName().is("Data") &&
isa<FuncDecl>(firstDecl) && isa<FuncDecl>(secondDecl) &&
firstDecl->getName() == secondDecl->getName() &&
firstDecl->getBaseName().userFacingName() == "withUnsafeBytes") {
// If the second module is the Foundation module and the first
// is the NIOFoundationCompat module, the second is shadowed by the
// first.
if (firstDecl->getModuleContext()->getName()
.is("NIOFoundationCompat") &&
secondDecl->getModuleContext()->getName().is("Foundation")) {
shadowed.insert(secondDecl);
continue;
}
// If it's the other way around, the first declaration is shadowed
// by the second.
if (secondDecl->getModuleContext()->getName()
.is("NIOFoundationCompat") &&
firstDecl->getModuleContext()->getName().is("Foundation")) {
shadowed.insert(firstDecl);
break;
}
}
}
}
// Prefer declarations in an overlay to similar declarations in
// the Clang module it customizes.
if (firstDecl->hasClangNode() != secondDecl->hasClangNode()) {
auto clangLoader = ctx.getClangModuleLoader();
if (!clangLoader) continue;
if (clangLoader->isInOverlayModuleForImportedModule(
firstDecl->getDeclContext(),
secondDecl->getDeclContext())) {
shadowed.insert(secondDecl);
continue;
}
if (clangLoader->isInOverlayModuleForImportedModule(
secondDecl->getDeclContext(),
firstDecl->getDeclContext())) {
shadowed.insert(firstDecl);
break;
}
}
}
}
}
/// Given a set of declarations whose names and generic signatures have matched,
/// figure out which of these declarations have been shadowed by others.
static void recordShadowedDeclsAfterSignatureMatch(
ArrayRef<ValueDecl *> decls,
const DeclContext *dc,
llvm::SmallPtrSetImpl<ValueDecl *> &shadowed) {
assert(decls.size() > 1 && "Nothing collided");
// Categorize all of the declarations based on their overload types.
llvm::SmallDenseMap<CanType, llvm::TinyPtrVector<ValueDecl *>> collisions;
llvm::SmallVector<CanType, 2> collisionTypes;
for (auto decl : decls) {
assert(!isa<TypeDecl>(decl));
CanType type;
// FIXME: The type of a variable or subscript doesn't include
// enough context to distinguish entities from different
// constrained extensions, so use the overload signature's
// type. This is layering a partial fix upon a total hack.
if (auto asd = dyn_cast<AbstractStorageDecl>(decl))
type = asd->getOverloadSignatureType();
else
type = decl->getInterfaceType()->getCanonicalType();
// Record this declaration based on its signature.
auto &known = collisions[type];
if (known.size() == 1) {
collisionTypes.push_back(type);
}
known.push_back(decl);
}
// Check whether we have shadowing for signature collisions.
for (auto type : collisionTypes) {
ArrayRef<ValueDecl *> collidingDecls = collisions[type];
recordShadowedDeclsAfterTypeMatch(collidingDecls, dc,
shadowed);
}
}
/// Look through the given set of declarations (that all have the same name),
/// recording those that are shadowed by another declaration in the
/// \c shadowed set.
static void recordShadowedDeclsForImportedInits(
ArrayRef<ConstructorDecl *> ctors,
llvm::SmallPtrSetImpl<ValueDecl *> &shadowed) {
assert(ctors.size() > 1 && "No collisions");
ASTContext &ctx = ctors.front()->getASTContext();
// Find the "best" constructor with this signature.
ConstructorDecl *bestCtor = ctors[0];
for (auto ctor : ctors.slice(1)) {
auto comparison = compareConstructors(ctor, bestCtor, ctx);
if (comparison == ConstructorComparison::Better)
bestCtor = ctor;
}
// Shadow any initializers that are worse.
for (auto ctor : ctors) {
auto comparison = compareConstructors(ctor, bestCtor, ctx);
if (comparison == ConstructorComparison::Worse)
shadowed.insert(ctor);
}
}
/// Look through the given set of declarations (that all have the same name),
/// recording those that are shadowed by another declaration in the
/// \c shadowed set.
static void recordShadowedDecls(ArrayRef<ValueDecl *> decls,
const DeclContext *dc,
llvm::SmallPtrSetImpl<ValueDecl *> &shadowed) {
if (decls.size() < 2)
return;
llvm::TinyPtrVector<ValueDecl *> typeDecls;
// Categorize all of the declarations based on their overload signatures.
llvm::SmallDenseMap<const GenericSignatureImpl *,
llvm::TinyPtrVector<ValueDecl *>> collisions;
llvm::SmallVector<const GenericSignatureImpl *, 2> collisionSignatures;
llvm::SmallDenseMap<NominalTypeDecl *,
llvm::TinyPtrVector<ConstructorDecl *>>
importedInitializerCollisions;
llvm::TinyPtrVector<NominalTypeDecl *> importedInitializerCollisionTypes;
for (auto decl : decls) {
if (auto *typeDecl = dyn_cast<TypeDecl>(decl)) {
typeDecls.push_back(typeDecl);
continue;
}
// Specifically keep track of imported initializers, which can come from
// Objective-C init methods, Objective-C factory methods, renamed C
// functions, or be synthesized by the importer.
if (decl->hasClangNode() ||
(isa<NominalTypeDecl>(decl->getDeclContext()) &&
cast<NominalTypeDecl>(decl->getDeclContext())->hasClangNode())) {
if (auto ctor = dyn_cast<ConstructorDecl>(decl)) {
auto nominal = ctor->getDeclContext()->getSelfNominalTypeDecl();
auto &knownInits = importedInitializerCollisions[nominal];
if (knownInits.size() == 1) {
importedInitializerCollisionTypes.push_back(nominal);
}
knownInits.push_back(ctor);
}
}
// If the decl is currently being validated, this is likely a recursive
// reference and we'll want to skip ahead so as to avoid having its type
// attempt to desugar itself.
if (decl->isRecursiveValidation())
continue;
CanGenericSignature signature;
auto *dc = decl->getInnermostDeclContext();
if (auto genericSig = dc->getGenericSignatureOfContext())
signature = genericSig->getCanonicalSignature();
// Record this declaration based on its signature.
auto &known = collisions[signature.getPointer()];
if (known.size() == 1) {
collisionSignatures.push_back(signature.getPointer());
}
known.push_back(decl);
}
// Check whether we have shadowing for type declarations.
if (typeDecls.size() > 1) {
ArrayRef<ValueDecl *> collidingDecls = typeDecls;
recordShadowedDeclsAfterTypeMatch(collidingDecls, dc, shadowed);
}
// Check whether we have shadowing for signature collisions.
for (auto signature : collisionSignatures) {
ArrayRef<ValueDecl *> collidingDecls = collisions[signature];
recordShadowedDeclsAfterSignatureMatch(collidingDecls, dc, shadowed);
}
// Check whether we have shadowing for imported initializer collisions.
for (auto nominal : importedInitializerCollisionTypes) {
recordShadowedDeclsForImportedInits(importedInitializerCollisions[nominal],
shadowed);
}
}
static void
recordShadowedDecls(ArrayRef<OperatorDecl *> decls, const DeclContext *dc,
llvm::SmallPtrSetImpl<OperatorDecl *> &shadowed) {
// Always considered to have the same signature.
recordShadowedDeclsAfterTypeMatch(decls, dc, shadowed);
}
static void
recordShadowedDecls(ArrayRef<PrecedenceGroupDecl *> decls,
const DeclContext *dc,
llvm::SmallPtrSetImpl<PrecedenceGroupDecl *> &shadowed) {
// Always considered to have the same type.
recordShadowedDeclsAfterTypeMatch(decls, dc, shadowed);
}
template <typename T, typename Container>
static bool removeShadowedDeclsImpl(Container &decls, const DeclContext *dc) {
// Collect declarations with the same (full) name.
llvm::SmallDenseMap<DeclName, llvm::TinyPtrVector<T>> collidingDeclGroups;
bool anyCollisions = false;
for (auto decl : decls) {
// Record this declaration based on its full name.
auto &knownDecls = collidingDeclGroups[decl->getName()];
if (!knownDecls.empty())
anyCollisions = true;
knownDecls.push_back(decl);
}
// If nothing collided, we're done.
if (!anyCollisions)
return false;
// Walk through the declarations again, marking any declarations that shadow.
llvm::SmallPtrSet<T, 4> shadowed;
for (auto decl : decls) {
auto known = collidingDeclGroups.find(decl->getName());
if (known == collidingDeclGroups.end()) {
// We already handled this group.
continue;
}
recordShadowedDecls(known->second, dc, shadowed);
collidingDeclGroups.erase(known);
}
// If no declarations were shadowed, we're done.
if (shadowed.empty())
return false;
// Remove shadowed declarations from the list of declarations.
bool anyRemoved = false;
decls.erase(std::remove_if(decls.begin(), decls.end(),
[&](T decl) {
if (shadowed.count(decl) > 0) {
anyRemoved = true;
return true;
}
return false;
}),
decls.end());
return anyRemoved;
}
bool swift::removeShadowedDecls(SmallVectorImpl<ValueDecl *> &decls,
const DeclContext *dc) {
return removeShadowedDeclsImpl<ValueDecl *>(decls, dc);
}
bool swift::removeShadowedDecls(TinyPtrVector<OperatorDecl *> &decls,
const DeclContext *dc) {
#ifndef NDEBUG
// Make sure all the operators have the same fixity.
if (decls.size() > 1) {
for (auto *op : decls)
assert(op->getFixity() == decls[0]->getFixity());
}
#endif
return removeShadowedDeclsImpl<OperatorDecl *>(decls, dc);
}
bool swift::removeShadowedDecls(TinyPtrVector<PrecedenceGroupDecl *> &decls,
const DeclContext *dc) {
return removeShadowedDeclsImpl<PrecedenceGroupDecl *>(decls, dc);
}
namespace {
enum class DiscriminatorMatch {
NoDiscriminator,
Matches,
Different
};
} // end anonymous namespace
static DiscriminatorMatch matchDiscriminator(Identifier discriminator,
const ValueDecl *value) {
if (value->getFormalAccess() > AccessLevel::FilePrivate)
return DiscriminatorMatch::NoDiscriminator;
auto containingFile =
dyn_cast<FileUnit>(value->getDeclContext()->getModuleScopeContext());
if (!containingFile)
return DiscriminatorMatch::Different;
if (discriminator == containingFile->getDiscriminatorForPrivateValue(value))
return DiscriminatorMatch::Matches;
return DiscriminatorMatch::Different;
}
static DiscriminatorMatch
matchDiscriminator(Identifier discriminator,
LookupResultEntry lookupResult) {
return matchDiscriminator(discriminator, lookupResult.getValueDecl());
}
template <typename Result>
void namelookup::filterForDiscriminator(SmallVectorImpl<Result> &results,
DebuggerClient *debugClient) {
if (debugClient == nullptr)
return;
Identifier discriminator = debugClient->getPreferredPrivateDiscriminator();
if (discriminator.empty())
return;
auto lastMatchIter = std::find_if(results.rbegin(), results.rend(),
[discriminator](Result next) -> bool {
return
matchDiscriminator(discriminator, next) == DiscriminatorMatch::Matches;
});
if (lastMatchIter == results.rend())
return;
Result lastMatch = *lastMatchIter;
auto newEnd = std::remove_if(results.begin(), lastMatchIter.base()-1,
[discriminator](Result next) -> bool {
return
matchDiscriminator(discriminator, next) == DiscriminatorMatch::Different;
});
results.erase(newEnd, results.end());
results.push_back(lastMatch);
}
template void namelookup::filterForDiscriminator<LookupResultEntry>(
SmallVectorImpl<LookupResultEntry> &results, DebuggerClient *debugClient);
namespace {
/// Whether we're looking up outer results or not.
enum class LookupOuterResults {
Excluded,
Included
};
}
/// Retrieve the set of type declarations that are directly referenced from
/// the given parsed type representation.
static DirectlyReferencedTypeDecls
directReferencesForTypeRepr(Evaluator &evaluator, ASTContext &ctx,
TypeRepr *typeRepr, DeclContext *dc);
/// Retrieve the set of type declarations that are directly referenced from
/// the given type.
static DirectlyReferencedTypeDecls directReferencesForType(Type type);
/// Given a set of type declarations, find all of the nominal type declarations
/// that they reference, looking through typealiases as appropriate.
static TinyPtrVector<NominalTypeDecl *>
resolveTypeDeclsToNominal(Evaluator &evaluator,
ASTContext &ctx,
ArrayRef<TypeDecl *> typeDecls,
SmallVectorImpl<ModuleDecl *> &modulesFound,
bool &anyObject);
SelfBounds SelfBoundsFromWhereClauseRequest::evaluate(
Evaluator &evaluator,
llvm::PointerUnion<const TypeDecl *, const ExtensionDecl *> decl) const {
auto *typeDecl = decl.dyn_cast<const TypeDecl *>();
auto *protoDecl = dyn_cast_or_null<const ProtocolDecl>(typeDecl);
auto *extDecl = decl.dyn_cast<const ExtensionDecl *>();
const DeclContext *dc =
protoDecl ? (const DeclContext *)protoDecl : (const DeclContext *)extDecl;
// A protocol or extension 'where' clause can reference associated types of
// the protocol itself, so we have to start unqualified lookup from 'dc'.
//
// However, the right hand side of a 'Self' conformance constraint must be
// resolved before unqualified lookup into 'dc' can work, so we make an
// exception here and begin lookup from the parent context instead.
auto *lookupDC = dc->getParent();
auto requirements = protoDecl ? protoDecl->getTrailingWhereClause()
: extDecl->getTrailingWhereClause();
ASTContext &ctx = dc->getASTContext();
SelfBounds result;
if (requirements == nullptr)
return result;
for (const auto &req : requirements->getRequirements()) {
// We only care about type constraints.
if (req.getKind() != RequirementReprKind::TypeConstraint)
continue;
// The left-hand side of the type constraint must be 'Self'.
bool isSelfLHS = false;
if (auto typeRepr = req.getSubjectRepr()) {
if (auto identTypeRepr = dyn_cast<SimpleIdentTypeRepr>(typeRepr))
isSelfLHS = (identTypeRepr->getNameRef().getBaseIdentifier() ==
ctx.Id_Self);
}
if (!isSelfLHS)
continue;
// Resolve the right-hand side.
DirectlyReferencedTypeDecls rhsDecls;
if (auto typeRepr = req.getConstraintRepr()) {
rhsDecls = directReferencesForTypeRepr(evaluator, ctx, typeRepr, lookupDC);
}
SmallVector<ModuleDecl *, 2> modulesFound;
auto rhsNominals = resolveTypeDeclsToNominal(evaluator, ctx, rhsDecls,
modulesFound,
result.anyObject);
result.decls.insert(result.decls.end(),
rhsNominals.begin(),
rhsNominals.end());
}
return result;
}
SelfBounds swift::getSelfBoundsFromWhereClause(
llvm::PointerUnion<const TypeDecl *, const ExtensionDecl *> decl) {
auto *typeDecl = decl.dyn_cast<const TypeDecl *>();
auto *extDecl = decl.dyn_cast<const ExtensionDecl *>();
auto &ctx = typeDecl ? typeDecl->getASTContext()
: extDecl->getASTContext();
return evaluateOrDefault(ctx.evaluator,
SelfBoundsFromWhereClauseRequest{decl}, {});
}
TinyPtrVector<TypeDecl *>
TypeDeclsFromWhereClauseRequest::evaluate(Evaluator &evaluator,
ExtensionDecl *ext) const {
ASTContext &ctx = ext->getASTContext();
TinyPtrVector<TypeDecl *> result;
auto resolve = [&](TypeRepr *typeRepr) {
auto decls = directReferencesForTypeRepr(evaluator, ctx, typeRepr, ext);
result.insert(result.end(), decls.begin(), decls.end());
};
if (auto *whereClause = ext->getTrailingWhereClause()) {
for (const auto &req : whereClause->getRequirements()) {
switch (req.getKind()) {
case RequirementReprKind::TypeConstraint:
resolve(req.getSubjectRepr());
resolve(req.getConstraintRepr());
break;
case RequirementReprKind::SameType:
resolve(req.getFirstTypeRepr());
resolve(req.getSecondTypeRepr());
break;
case RequirementReprKind::LayoutConstraint:
resolve(req.getSubjectRepr());
break;
}
}
}
return result;
}
#pragma mark Member lookup table
void LazyMemberLoader::anchor() {}
void LazyConformanceLoader::anchor() {}
/// Lookup table used to store members of a nominal type (and its extensions)
/// for fast retrieval.
class swift::MemberLookupTable {
/// The last extension that was included within the member lookup table's
/// results.
ExtensionDecl *LastExtensionIncluded = nullptr;
/// The type of the internal lookup table.
typedef llvm::DenseMap<DeclName, llvm::TinyPtrVector<ValueDecl *>>
LookupTable;
/// Lookup table mapping names to the set of declarations with that name.
LookupTable Lookup;
/// The set of names of lazily-loaded members that the lookup table has a
/// complete accounting of with respect to all known extensions of its
/// parent nominal type.
llvm::DenseSet<DeclBaseName> LazilyCompleteNames;
public:
/// Create a new member lookup table.
explicit MemberLookupTable(ASTContext &ctx);
/// Update a lookup table with members from newly-added extensions.
void updateLookupTable(NominalTypeDecl *nominal);
/// Add the given member to the lookup table.
void addMember(Decl *members);
/// Add the given members to the lookup table.
void addMembers(DeclRange members);
/// Returns \c true if the lookup table has a complete accounting of the
/// given name.
bool isLazilyComplete(DeclBaseName name) const {
return LazilyCompleteNames.find(name) != LazilyCompleteNames.end();
}
/// Mark a given lazily-loaded name as being complete.
void markLazilyComplete(DeclBaseName name) {
LazilyCompleteNames.insert(name);
}
/// Clears the cache of lazily-complete names. This _must_ be called when
/// new extensions with lazy members are added to the type, or direct lookup
/// will return inconsistent or stale results.
void clearLazilyCompleteCache() {
LazilyCompleteNames.clear();
}
/// Iterator into the lookup table.
typedef LookupTable::iterator iterator;
iterator begin() { return Lookup.begin(); }
iterator end() { return Lookup.end(); }
iterator find(DeclName name) {
return Lookup.find(name);
}
void dump(llvm::raw_ostream &os) const {
os << "LastExtensionIncluded:\n";
if (LastExtensionIncluded)
LastExtensionIncluded->printContext(os, 2);
else
os << " nullptr\n";
os << "Lookup:\n ";
for (auto &pair : Lookup) {
pair.getFirst().print(os);
if (isLazilyComplete(pair.getFirst().getBaseName())) {
os << " (lazily complete)";
}
os << ":\n ";
for (auto &decl : pair.getSecond()) {
os << "- ";
decl->dumpRef(os);
os << "\n ";
}
}
os << "\n";
}
SWIFT_DEBUG_DUMP {
dump(llvm::errs());
}
// Only allow allocation of member lookup tables using the allocator in
// ASTContext or by doing a placement new.
void *operator new(size_t Bytes, ASTContext &C,
unsigned Alignment = alignof(MemberLookupTable)) {
return C.Allocate(Bytes, Alignment);
}
void *operator new(size_t Bytes, void *Mem) {
assert(Mem);
return Mem;
}
};
namespace {
/// Stores the set of Objective-C methods with a given selector within the
/// Objective-C method lookup table.
struct StoredObjCMethods {
/// The generation count at which this list was last updated.
unsigned Generation = 0;
/// The set of methods with the given selector.
llvm::TinyPtrVector<AbstractFunctionDecl *> Methods;
};
} // end anonymous namespace
/// Class member lookup table, which is a member lookup table with a second
/// table for lookup based on Objective-C selector.
class ClassDecl::ObjCMethodLookupTable
: public llvm::DenseMap<std::pair<ObjCSelector, char>,
StoredObjCMethods>
{
public:
// Only allow allocation of member lookup tables using the allocator in
// ASTContext or by doing a placement new.
void *operator new(size_t Bytes, ASTContext &C,
unsigned Alignment = alignof(MemberLookupTable)) {
return C.Allocate(Bytes, Alignment);
}
void *operator new(size_t Bytes, void *Mem) {
assert(Mem);
return Mem;
}
};
MemberLookupTable::MemberLookupTable(ASTContext &ctx) {
// Register a cleanup with the ASTContext to call the lookup table
// destructor.
ctx.addCleanup([this]() {
this->~MemberLookupTable();
});
}
void MemberLookupTable::addMember(Decl *member) {
// Only value declarations matter.
auto vd = dyn_cast<ValueDecl>(member);
if (!vd)
return;
// @_implements members get added under their declared name.
auto A = vd->getAttrs().getAttribute<ImplementsAttr>();
// Unnamed entities w/o @_implements synonyms cannot be found by name lookup.
if (!A && !vd->hasName())
return;
// If this declaration is already in the lookup table, don't add it
// again.
if (vd->isAlreadyInLookupTable()) {
return;
}
vd->setAlreadyInLookupTable();
// Add this declaration to the lookup set under its compound name and simple
// name.
vd->getName().addToLookupTable(Lookup, vd);
// And if given a synonym, under that name too.
if (A)
A->getMemberName().addToLookupTable(Lookup, vd);
}
void MemberLookupTable::addMembers(DeclRange members) {
for (auto member : members) {
addMember(member);
}
}
void MemberLookupTable::updateLookupTable(NominalTypeDecl *nominal) {
// If the last extension we included is the same as the last known extension,
// we're already up-to-date.
if (LastExtensionIncluded == nominal->LastExtension)
return;
// Add members from each of the extensions that we have not yet visited.
for (auto next = LastExtensionIncluded
? LastExtensionIncluded->NextExtension.getPointer()
: nominal->FirstExtension;
next;
(LastExtensionIncluded = next,next = next->NextExtension.getPointer())) {
addMembers(next->getMembers());
}
}
void NominalTypeDecl::addedExtension(ExtensionDecl *ext) {
if (!LookupTable) return;
if (ext->hasLazyMembers()) {
LookupTable->addMembers(ext->getCurrentMembersWithoutLoading());
LookupTable->clearLazilyCompleteCache();
} else {
LookupTable->addMembers(ext->getMembers());
}
}
void NominalTypeDecl::addedMember(Decl *member) {
// If we have a lookup table, add the new member to it. If not, we'll pick up
// this member when we first create the table.
auto *vd = dyn_cast<ValueDecl>(member);
auto *lookup = LookupTable;
if (!vd || !lookup)
return;
lookup->addMember(vd);
}
void ExtensionDecl::addedMember(Decl *member) {
// If this extension has already been bound to a nominal, add the new member
// to the nominal's lookup table.
if (NextExtension.getInt()) {
auto nominal = getExtendedNominal();
if (nominal)
nominal->addedMember(member);
}
}
// For lack of anywhere more sensible to put it, here's a diagram of the pieces
// involved in finding members and extensions of a NominalTypeDecl.
//
// ┌────────────────────────────┬─┐
// │IterableDeclContext │ │ ┌─────────────────────────────┐
// │------------------- │ │ │┌───────────────┬┐ ▼
// │Decl *LastDecl ───────────┼─┼─────┘│Decl ││ ┌───────────────┬┐
// │Decl *FirstDecl ───────────┼─┼─────▶│---- ││ │Decl ││
// │ │ │ │Decl *NextDecl├┼─▶│---- ││
// │bool HasLazyMembers │ │ ├───────────────┘│ │Decl *NextDecl ││
// │IterableDeclContextKind Kind│ │ │ │ ├───────────────┘│
// │ │ │ │ValueDecl │ │ │
// ├────────────────────────────┘ │ │--------- │ │ValueDecl │
// │ │ │DeclName Name │ │--------- │
// │NominalTypeDecl │ └────────────────┘ │DeclName Name │
// │--------------- │ ▲ └────────────────┘
// │ExtensionDecl *FirstExtension─┼────────┐ │ ▲
// │ExtensionDecl *LastExtension ─┼───────┐│ │ └───┐
// │ │ ││ └──────────────────────┐│
// │MemberLookupTable *LookupTable├─┐ ││ ││
// └──────────────────────────────┘ │ ││ ┌─────────────────┐ ││
// │ ││ │ExtensionDecl │ ││
// │ ││ │------------- │ ││
// ┌─────────────┘ │└────▶│ExtensionDecl │ ││
// │ │ │ *NextExtension ├──┐ ││
// ▼ │ └─────────────────┘ │ ││
// ┌─────────────────────────────────────┐│ ┌─────────────────┐ │ ││
// │MemberLookupTable ││ │ExtensionDecl │ │ ││
// │----------------- ││ │------------- │ │ ││
// │ExtensionDecl *LastExtensionIncluded ├┴─────▶│ExtensionDecl │◀─┘ ││
// │ │ │ *NextExtension │ ││
// │┌───────────────────────────────────┐│ └─────────────────┘ ││
// ││DenseMap<Declname, ...> LookupTable││ ││
// ││-----------------------------------││ ┌──────────────────────────┐ ││
// ││[NameA] TinyPtrVector<ValueDecl *> ││ │TinyPtrVector<ValueDecl *>│ ││
// ││[NameB] TinyPtrVector<ValueDecl *> ││ │--------------------------│ ││
// ││[NameC] TinyPtrVector<ValueDecl *>─┼┼─▶│[0] ValueDecl * ─────┼─┘│
// │└───────────────────────────────────┘│ │[1] ValueDecl * ─────┼──┘
// └─────────────────────────────────────┘ └──────────────────────────┘
//
// The HasLazyMembers, Kind, and LookupTableComplete fields are packed into
// PointerIntPairs so don't go grepping for them; but for purposes of
// illustration they are effectively their own fields.
//
// MemberLookupTable is populated en-masse when the IterableDeclContext's
// (IDC's) list of Decls is populated. But MemberLookupTable can also be
// populated incrementally by one-name-at-a-time lookups by lookupDirect, in
// which case those Decls are _not_ added to the IDC's list. They are cached in
// the loader they come from, lifecycle-wise, and are added to the
// MemberLookupTable to accelerate subsequent retrieval, but the IDC is not
// considered populated until someone calls getMembers().
//
// If the IDC list is later populated and/or an extension is added _after_
// MemberLookupTable is constructed (and possibly has entries in it),
// MemberLookupTable is incrementally reconstituted with new members.
static void
populateLookupTableEntryFromLazyIDCLoader(ASTContext &ctx,
MemberLookupTable &LookupTable,
DeclBaseName name,
IterableDeclContext *IDC) {
auto ci = ctx.getOrCreateLazyIterableContextData(IDC,
/*lazyLoader=*/nullptr);
auto res = ci->loader->loadNamedMembers(IDC, name, ci->memberData);
if (auto s = ctx.Stats) {
++s->getFrontendCounters().NamedLazyMemberLoadSuccessCount;
}
for (auto d : res) {
LookupTable.addMember(d);
}
}
static void
populateLookupTableEntryFromExtensions(ASTContext &ctx,
MemberLookupTable &table,
DeclBaseName name,
NominalTypeDecl *nominal) {
assert(!table.isLazilyComplete(name) &&
"Should not be searching extensions for complete name!");
for (auto e : nominal->getExtensions()) {
// If there's no lazy members to look at, all the members of this extension
// are present in the lookup table.
if (!e->hasLazyMembers()) {
continue;
}
assert(e->wasDeserialized() || e->hasClangNode() &&
"Extension without deserializable content has lazy members!");
assert(!e->hasUnparsedMembers());
populateLookupTableEntryFromLazyIDCLoader(ctx, table, name, e);
}
}
void NominalTypeDecl::prepareLookupTable() {
// If we have already allocated the lookup table, then there's nothing further
// to do.
if (LookupTable) {
return;
}
// Otherwise start the first fill.
auto &ctx = getASTContext();
LookupTable = new (ctx) MemberLookupTable(ctx);
if (hasLazyMembers()) {
assert(!hasUnparsedMembers());
LookupTable->addMembers(getCurrentMembersWithoutLoading());
} else {
LookupTable->addMembers(getMembers());
}
for (auto e : getExtensions()) {
// If we can lazy-load this extension, only take the members we've loaded
// so far.
if (e->wasDeserialized() || e->hasClangNode()) {
LookupTable->addMembers(e->getCurrentMembersWithoutLoading());
continue;
}
// Else, load all the members into the table.
LookupTable->addMembers(e->getMembers());
}
}
static TinyPtrVector<ValueDecl *>
maybeFilterOutAttrImplements(TinyPtrVector<ValueDecl *> decls,
DeclName name,
bool includeAttrImplements) {
if (includeAttrImplements)
return decls;
TinyPtrVector<ValueDecl*> result;
for (auto V : decls) {
// Filter-out any decl that doesn't have the name we're looking for
// (asserting as a consistency-check that such entries all have
// @_implements attrs for the name!)
if (V->getName().matchesRef(name)) {
result.push_back(V);
} else {
auto A = V->getAttrs().getAttribute<ImplementsAttr>();
(void)A;
assert(A && A->getMemberName().matchesRef(name));
}
}
return result;
}
TinyPtrVector<ValueDecl *>
NominalTypeDecl::lookupDirect(DeclName name,
OptionSet<LookupDirectFlags> flags) {
return evaluateOrDefault(getASTContext().evaluator,
DirectLookupRequest({this, name, flags}), {});
}
TinyPtrVector<ValueDecl *>
DirectLookupRequest::evaluate(Evaluator &evaluator,
DirectLookupDescriptor desc) const {
const auto &name = desc.Name;
const auto flags = desc.Options;
auto *decl = desc.DC;
// We only use NamedLazyMemberLoading when a user opts-in and we have
// not yet loaded all the members into the IDC list in the first place.
ASTContext &ctx = decl->getASTContext();
const bool useNamedLazyMemberLoading = (ctx.LangOpts.NamedLazyMemberLoading &&
decl->hasLazyMembers());
const bool disableAdditionalExtensionLoading =
flags.contains(NominalTypeDecl::LookupDirectFlags::IgnoreNewExtensions);
const bool includeAttrImplements =
flags.contains(NominalTypeDecl::LookupDirectFlags::IncludeAttrImplements);
LLVM_DEBUG(llvm::dbgs() << decl->getNameStr() << ".lookupDirect("
<< name << ")"
<< ", hasLazyMembers()=" << decl->hasLazyMembers()
<< ", useNamedLazyMemberLoading="
<< useNamedLazyMemberLoading
<< "\n");
decl->prepareLookupTable();
// If we're allowed to load extensions, call prepareExtensions to ensure we
// properly invalidate the lazily-complete cache for any extensions brought in
// by modules loaded after-the-fact. This can happen with the LLDB REPL.
if (!disableAdditionalExtensionLoading)
decl->prepareExtensions();
auto &Table = *decl->LookupTable;
if (!useNamedLazyMemberLoading) {
// Make sure we have the complete list of members (in this nominal and in
// all extensions).
(void)decl->getMembers();
if (!disableAdditionalExtensionLoading) {
for (auto E : decl->getExtensions())
(void)E->getMembers();
Table.updateLookupTable(decl);
}
} else if (!Table.isLazilyComplete(name.getBaseName())) {
// The lookup table believes it doesn't have a complete accounting of this
// name - either because we're never seen it before, or another extension
// was registered since the last time we searched. Ask the loaders to give
// us a hand.
DeclBaseName baseName(name.getBaseName());
populateLookupTableEntryFromLazyIDCLoader(ctx, Table, baseName, decl);
if (!disableAdditionalExtensionLoading) {
populateLookupTableEntryFromExtensions(ctx, Table, baseName, decl);
}
// FIXME: If disableAdditionalExtensionLoading is true, we should
// not mark the entry as complete.
Table.markLazilyComplete(baseName);
}
// Look for a declaration with this name.
auto known = Table.find(name);
if (known == Table.end()) {
return TinyPtrVector<ValueDecl *>();
}
// We found something; return it.
return maybeFilterOutAttrImplements(known->second, name,
includeAttrImplements);
}
void ClassDecl::createObjCMethodLookup() {
assert(!ObjCMethodLookup && "Already have an Objective-C member table");
auto &ctx = getASTContext();
ObjCMethodLookup = new (ctx) ObjCMethodLookupTable();
// Register a cleanup with the ASTContext to call the lookup table
// destructor.
ctx.addCleanup([this]() {
this->ObjCMethodLookup->~ObjCMethodLookupTable();
});
}
TinyPtrVector<AbstractFunctionDecl *>
ClassDecl::lookupDirect(ObjCSelector selector, bool isInstance) {
if (!ObjCMethodLookup) {
createObjCMethodLookup();
}
// If any modules have been loaded since we did the search last (or if we
// hadn't searched before), look in those modules, too.
auto &stored = (*ObjCMethodLookup)[{selector, isInstance}];
ASTContext &ctx = getASTContext();
if (ctx.getCurrentGeneration() > stored.Generation) {
ctx.loadObjCMethods(this, selector, isInstance, stored.Generation,
stored.Methods);
stored.Generation = ctx.getCurrentGeneration();
}
return stored.Methods;
}
void ClassDecl::recordObjCMethod(AbstractFunctionDecl *method,
ObjCSelector selector) {
if (!ObjCMethodLookup) {
createObjCMethodLookup();
}
// Record the method.
bool isInstanceMethod = method->isObjCInstanceMethod();
auto &vec = (*ObjCMethodLookup)[{selector, isInstanceMethod}].Methods;
// Check whether we have a duplicate. This only checks more than one
// element in ill-formed code, so the linear search is acceptable.
if (std::find(vec.begin(), vec.end(), method) != vec.end())
return;
if (auto *sf = method->getParentSourceFile()) {
if (vec.size() == 1) {
// We have a conflict.
sf->ObjCMethodConflicts.push_back(std::make_tuple(this, selector,
isInstanceMethod));
} if (vec.empty()) {
sf->ObjCMethodList.push_back(method);
}
}
vec.push_back(method);
}
/// Determine whether the given declaration is an acceptable lookup
/// result when searching from the given DeclContext.
static bool isAcceptableLookupResult(const DeclContext *dc,
NLOptions options,
ValueDecl *decl,
bool onlyCompleteObjectInits) {
// Filter out designated initializers, if requested.
if (onlyCompleteObjectInits) {
if (auto ctor = dyn_cast<ConstructorDecl>(decl)) {
if (isa<ClassDecl>(ctor->getDeclContext()) && !ctor->isInheritable())
return false;
} else {
return false;
}
}
// Ignore stub implementations.
if (auto ctor = dyn_cast<ConstructorDecl>(decl)) {
if (ctor->hasStubImplementation())
return false;
}
// Check access.
if (!(options & NL_IgnoreAccessControl) &&
!dc->getASTContext().isAccessControlDisabled()) {
bool allowUsableFromInline = options & NL_IncludeUsableFromInline;
return decl->isAccessibleFrom(dc, /*forConformance*/ false,
allowUsableFromInline);
}
return true;
}
void namelookup::pruneLookupResultSet(const DeclContext *dc, NLOptions options,
SmallVectorImpl<ValueDecl *> &decls) {
// If we're supposed to remove overridden declarations, do so now.
if (options & NL_RemoveOverridden)
removeOverriddenDecls(decls);
// If we're supposed to remove shadowed/hidden declarations, do so now.
if (options & NL_RemoveNonVisible)
removeShadowedDecls(decls, dc);
ModuleDecl *M = dc->getParentModule();
filterForDiscriminator(decls, M->getDebugClient());
}
/// Inspect the given type to determine which nominal type declarations it
/// directly references, to facilitate name lookup into those types.
static void extractDirectlyReferencedNominalTypes(
Type type, SmallVectorImpl<NominalTypeDecl *> &decls) {
if (auto nominal = type->getAnyNominal()) {
decls.push_back(nominal);
return;
}
if (auto unbound = type->getAs<UnboundGenericType>()) {
if (auto nominal = dyn_cast<NominalTypeDecl>(unbound->getDecl()))
decls.push_back(nominal);
return;
}
if (auto archetypeTy = type->getAs<ArchetypeType>()) {
// Look in the protocols to which the archetype conforms (always).
for (auto proto : archetypeTy->getConformsTo())
decls.push_back(proto);
// Look into the superclasses of this archetype.
if (auto superclass = archetypeTy->getSuperclass()) {
if (auto superclassDecl = superclass->getClassOrBoundGenericClass())
decls.push_back(superclassDecl);
}
return;
}
if (auto compositionTy = type->getAs<ProtocolCompositionType>()) {
auto layout = compositionTy->getExistentialLayout();
for (auto proto : layout.getProtocols()) {
auto *protoDecl = proto->getDecl();
decls.push_back(protoDecl);
}
if (auto superclass = layout.explicitSuperclass) {
auto *superclassDecl = superclass->getClassOrBoundGenericClass();
if (superclassDecl)
decls.push_back(superclassDecl);
}
return;
}
llvm_unreachable("Not a type containing nominal types?");
}
bool DeclContext::lookupQualified(Type type,
DeclNameRef member,
NLOptions options,
SmallVectorImpl<ValueDecl *> &decls) const {
using namespace namelookup;
assert(decls.empty() && "additive lookup not supported");
// Handle AnyObject lookup.
if (type->isAnyObject()) {
AnyObjectLookupRequest req(this, member, options);
decls = evaluateOrDefault(getASTContext().evaluator, req, {});
return !decls.empty();
}
// Handle lookup in a module.
if (auto moduleTy = type->getAs<ModuleType>())
return lookupQualified(moduleTy->getModule(), member, options, decls);
// Figure out which nominal types we will look into.
SmallVector<NominalTypeDecl *, 4> nominalTypesToLookInto;
extractDirectlyReferencedNominalTypes(type, nominalTypesToLookInto);
return lookupQualified(nominalTypesToLookInto, member, options, decls);
}
static void installPropertyWrapperMembersIfNeeded(NominalTypeDecl *target,
DeclNameRef member) {
auto &Context = target->getASTContext();
auto baseName = member.getBaseName();
if (!member.isSimpleName() || baseName.isSpecial())
return;
if ((!baseName.getIdentifier().str().startswith("$") &&
!baseName.getIdentifier().str().startswith("_")) ||
baseName.getIdentifier().str().size() <= 1) {
return;
}
// $- and _-prefixed variables can be generated by properties that have
// attached property wrappers.
auto originalPropertyName =
Context.getIdentifier(baseName.getIdentifier().str().substr(1));
for (auto member : target->lookupDirect(originalPropertyName)) {
if (auto var = dyn_cast<VarDecl>(member)) {
if (var->hasAttachedPropertyWrapper()) {
auto sourceFile = var->getDeclContext()->getParentSourceFile();
if (sourceFile && sourceFile->Kind != SourceFileKind::Interface)
(void)var->getPropertyWrapperBackingProperty();
}
}
}
}
bool DeclContext::lookupQualified(ArrayRef<NominalTypeDecl *> typeDecls,
DeclNameRef member,
NLOptions options,
SmallVectorImpl<ValueDecl *> &decls) const {
assert(decls.empty() && "additive lookup not supported");
QualifiedLookupRequest req{this, {typeDecls.begin(), typeDecls.end()},
member, options};
decls = evaluateOrDefault(getASTContext().evaluator, req, {});
return !decls.empty();
}
QualifiedLookupResult
QualifiedLookupRequest::evaluate(Evaluator &eval, const DeclContext *DC,
SmallVector<NominalTypeDecl *, 4> typeDecls,
DeclNameRef member, NLOptions options) const {
using namespace namelookup;
QualifiedLookupResult decls;
// Tracking for the nominal types we'll visit.
SmallVector<NominalTypeDecl *, 4> stack;
llvm::SmallPtrSet<NominalTypeDecl *, 4> visited;
bool sawClassDecl = false;
// Add the given nominal type to the stack.
auto addNominalType = [&](NominalTypeDecl *nominal) {
if (!visited.insert(nominal).second)
return false;
if (isa<ClassDecl>(nominal))
sawClassDecl = true;
stack.push_back(nominal);
return true;
};
// Add all of the nominal types to the stack.
for (auto nominal : typeDecls) {
addNominalType(nominal);
}
// Whether we only want to return complete object initializers.
bool onlyCompleteObjectInits = false;
// Visit all of the nominal types we know about, discovering any others
// we need along the way.
bool wantProtocolMembers = (options & NL_ProtocolMembers);
while (!stack.empty()) {
auto current = stack.back();
stack.pop_back();
// Make sure we've resolved property wrappers, if we need them.
installPropertyWrapperMembersIfNeeded(current, member);
// Look for results within the current nominal type and its extensions.
bool currentIsProtocol = isa<ProtocolDecl>(current);
auto flags = OptionSet<NominalTypeDecl::LookupDirectFlags>();
if (options & NL_IncludeAttributeImplements)
flags |= NominalTypeDecl::LookupDirectFlags::IncludeAttrImplements;
for (auto decl : current->lookupDirect(member.getFullName(), flags)) {
// If we're performing a type lookup, don't even attempt to validate
// the decl if its not a type.
if ((options & NL_OnlyTypes) && !isa<TypeDecl>(decl))
continue;
if (isAcceptableLookupResult(DC, options, decl, onlyCompleteObjectInits))
decls.push_back(decl);
}
// Visit superclass.
if (auto classDecl = dyn_cast<ClassDecl>(current)) {
// If we're looking for initializers, only look at the superclass if the
// current class permits inheritance. Even then, only find complete
// object initializers.
bool visitSuperclass = true;
if (member.getBaseName() == DeclBaseName::createConstructor()) {
if (classDecl->inheritsSuperclassInitializers())
onlyCompleteObjectInits = true;
else
visitSuperclass = false;
}
if (visitSuperclass) {
if (auto superclassDecl = classDecl->getSuperclassDecl())
if (visited.insert(superclassDecl).second)
stack.push_back(superclassDecl);
}
}
// If we're not looking at a protocol and we're not supposed to
// visit the protocols that this type conforms to, skip the next
// step.
if (!wantProtocolMembers && !currentIsProtocol)
continue;
SmallVector<ProtocolDecl *, 4> protocols;
if (auto *protoDecl = dyn_cast<ProtocolDecl>(current)) {
// If we haven't seen a class declaration yet, look into the protocol.
if (!sawClassDecl) {
if (auto superclassDecl = protoDecl->getSuperclassDecl()) {
visited.insert(superclassDecl);
stack.push_back(superclassDecl);
}
}
// Collect inherited protocols.
for (auto inheritedProto : protoDecl->getInheritedProtocols()) {
addNominalType(inheritedProto);
}
} else {
// Collect the protocols to which the nominal type conforms.
for (auto proto : current->getAllProtocols()) {
if (visited.insert(proto).second) {
stack.push_back(proto);
}
}
// For a class, we don't need to visit the protocol members of the
// superclass: that's already handled.
if (isa<ClassDecl>(current))
wantProtocolMembers = false;
}
}
pruneLookupResultSet(DC, options, decls);
if (auto *debugClient = DC->getParentModule()->getDebugClient()) {
debugClient->finishLookupInNominals(DC, typeDecls, member.getFullName(),
options, decls);
}
return decls;
}
bool DeclContext::lookupQualified(ModuleDecl *module, DeclNameRef member,
NLOptions options,
SmallVectorImpl<ValueDecl *> &decls) const {
assert(decls.empty() && "additive lookup not supported");
ModuleQualifiedLookupRequest req{this, module, member, options};
decls = evaluateOrDefault(getASTContext().evaluator, req, {});
return !decls.empty();
}
QualifiedLookupResult
ModuleQualifiedLookupRequest::evaluate(Evaluator &eval, const DeclContext *DC,
ModuleDecl *module, DeclNameRef member,
NLOptions options) const {
using namespace namelookup;
QualifiedLookupResult decls;
auto kind = (options & NL_OnlyTypes
? ResolutionKind::TypesOnly
: ResolutionKind::Overloadable);
auto topLevelScope = DC->getModuleScopeContext();
if (module == topLevelScope->getParentModule()) {
lookupInModule(module, member.getFullName(), decls, NLKind::QualifiedLookup,
kind, topLevelScope, options);
} else {
// Note: This is a lookup into another module. Unless we're compiling
// multiple modules at once, or if the other module re-exports this one,
// it shouldn't be possible to have a dependency from that module on
// anything in this one.
// Perform the lookup in all imports of this module.
auto &ctx = DC->getASTContext();
auto accessPaths = ctx.getImportCache().getAllVisibleAccessPaths(
module, topLevelScope);
if (llvm::any_of(accessPaths,
[&](ImportPath::Access accessPath) {
return accessPath.matches(member.getFullName());
})) {
lookupInModule(module, member.getFullName(), decls,
NLKind::QualifiedLookup, kind, topLevelScope,
options);
}
}
pruneLookupResultSet(DC, options, decls);
if (auto *debugClient = DC->getParentModule()->getDebugClient()) {
debugClient->finishLookupInModule(DC, module, member.getFullName(),
options, decls);
}
return decls;
}
QualifiedLookupResult
AnyObjectLookupRequest::evaluate(Evaluator &evaluator, const DeclContext *dc,
DeclNameRef member, NLOptions options) const {
using namespace namelookup;
QualifiedLookupResult decls;
#if SWIFT_BUILD_ONLY_SYNTAXPARSERLIB
// Avoid calling `clang::ObjCMethodDecl::isDirectMethod()`.
return decls;
#endif
// Type-only lookup won't find anything on AnyObject.
if (options & NL_OnlyTypes)
return decls;
// Collect all of the visible declarations.
SmallVector<ValueDecl *, 4> allDecls;
for (auto import : namelookup::getAllImports(dc)) {
import.importedModule->lookupClassMember(import.accessPath,
member.getFullName(), allDecls);
}
// For each declaration whose context is not something we've
// already visited above, add it to the list of declarations.
llvm::SmallPtrSet<ValueDecl *, 4> knownDecls;
for (auto decl : allDecls) {
// If the declaration is not @objc, it cannot be called dynamically.
if (!decl->isObjC())
continue;
// If the declaration is objc_direct, it cannot be called dynamically.
if (auto clangDecl = decl->getClangDecl()) {
if (auto objCMethod = dyn_cast<clang::ObjCMethodDecl>(clangDecl)) {
if (objCMethod->isDirectMethod())
continue;
} else if (auto objCProperty = dyn_cast<clang::ObjCPropertyDecl>(clangDecl)) {
if (objCProperty->isDirectProperty())
continue;
}
}
// If the declaration has an override, name lookup will also have
// found the overridden method. Skip this declaration, because we
// prefer the overridden method.
if (decl->getOverriddenDecl())
continue;
assert(decl->getDeclContext()->isTypeContext() &&
"Couldn't find nominal type?");
// If we didn't see this declaration before, and it's an acceptable
// result, add it to the list.
if (knownDecls.insert(decl).second &&
isAcceptableLookupResult(dc, options, decl,
/*onlyCompleteObjectInits=*/false))
decls.push_back(decl);
}
pruneLookupResultSet(dc, options, decls);
if (auto *debugClient = dc->getParentModule()->getDebugClient()) {
debugClient->finishLookupInAnyObject(dc, member.getFullName(), options,
decls);
}
return decls;
}
void DeclContext::lookupAllObjCMethods(
ObjCSelector selector,
SmallVectorImpl<AbstractFunctionDecl *> &results) const {
// Collect all of the methods with this selector.
for (auto import : namelookup::getAllImports(this)) {
import.importedModule->lookupObjCMethods(selector, results);
}
// Filter out duplicates.
llvm::SmallPtrSet<AbstractFunctionDecl *, 8> visited;
results.erase(
std::remove_if(results.begin(), results.end(),
[&](AbstractFunctionDecl *func) -> bool {
return !visited.insert(func).second;
}),
results.end());
}
/// Given a set of type declarations, find all of the nominal type declarations
/// that they reference, looking through typealiases as appropriate.
static TinyPtrVector<NominalTypeDecl *>
resolveTypeDeclsToNominal(Evaluator &evaluator,
ASTContext &ctx,
ArrayRef<TypeDecl *> typeDecls,
SmallVectorImpl<ModuleDecl *> &modulesFound,
bool &anyObject,
llvm::SmallPtrSetImpl<TypeAliasDecl *> &typealiases) {
SmallPtrSet<NominalTypeDecl *, 4> knownNominalDecls;
TinyPtrVector<NominalTypeDecl *> nominalDecls;
auto addNominalDecl = [&](NominalTypeDecl *nominal) {
if (knownNominalDecls.insert(nominal).second)
nominalDecls.push_back(nominal);
};
for (auto typeDecl : typeDecls) {
// Nominal type declarations get copied directly.
if (auto nominalDecl = dyn_cast<NominalTypeDecl>(typeDecl)) {
addNominalDecl(nominalDecl);
continue;
}
// Recursively resolve typealiases.
if (auto typealias = dyn_cast<TypeAliasDecl>(typeDecl)) {
// FIXME: Ad hoc recursion breaking, so we don't look through the
// same typealias multiple times.
if (!typealiases.insert(typealias).second)
continue;
auto underlyingTypeReferences = evaluateOrDefault(evaluator,
UnderlyingTypeDeclsReferencedRequest{typealias}, {});
auto underlyingNominalReferences
= resolveTypeDeclsToNominal(evaluator, ctx, underlyingTypeReferences,
modulesFound, anyObject, typealiases);
std::for_each(underlyingNominalReferences.begin(),
underlyingNominalReferences.end(),
addNominalDecl);
// Recognize Swift.AnyObject directly.
if (typealias->getName().is("AnyObject")) {
// TypeRepr version: Builtin.AnyObject
if (auto typeRepr = typealias->getUnderlyingTypeRepr()) {
if (auto compound = dyn_cast<CompoundIdentTypeRepr>(typeRepr)) {
auto components = compound->getComponents();
if (components.size() == 2 &&
components[0]->getNameRef().isSimpleName("Builtin") &&
components[1]->getNameRef().isSimpleName("AnyObject")) {
anyObject = true;
}
}
}
// Type version: an empty class-bound existential.
if (typealias->hasInterfaceType()) {
if (auto type = typealias->getUnderlyingType())
if (type->isAnyObject())
anyObject = true;
}
}
continue;
}
// Keep track of modules we see.
if (auto module = dyn_cast<ModuleDecl>(typeDecl)) {
modulesFound.push_back(module);
continue;
}
// Make sure we didn't miss some interesting kind of type declaration.
assert(isa<AbstractTypeParamDecl>(typeDecl));
}
return nominalDecls;
}
static TinyPtrVector<NominalTypeDecl *>
resolveTypeDeclsToNominal(Evaluator &evaluator,
ASTContext &ctx,
ArrayRef<TypeDecl *> typeDecls,
SmallVectorImpl<ModuleDecl *> &modulesFound,
bool &anyObject) {
llvm::SmallPtrSet<TypeAliasDecl *, 4> typealiases;
return resolveTypeDeclsToNominal(evaluator, ctx, typeDecls, modulesFound,
anyObject, typealiases);
}
/// Perform unqualified name lookup for types at the given location.
static DirectlyReferencedTypeDecls
directReferencesForUnqualifiedTypeLookup(DeclNameRef name,
SourceLoc loc, DeclContext *dc,
LookupOuterResults lookupOuter) {
// In a protocol or protocol extension, the 'where' clause can refer to
// associated types without 'Self' qualification:
//
// protocol MyProto where AssocType : Q { ... }
//
// extension MyProto where AssocType == Int { ... }
//
// For this reason, ASTScope maps source locations inside the 'where'
// clause to a scope that performs the lookup into the protocol or
// protocol extension.
//
// However, protocol and protocol extensions can also put bounds on 'Self',
// for example:
//
// protocol MyProto where Self : MyClass { ... }
//
// We must start searching for 'MyClass' at the top level, otherwise
// we end up with a cycle, because qualified lookup wants to resolve
// 'Self' bounds to build the set of declarations to search inside of.
//
// To make this work, we handle the top-level lookup case explicitly
// here, bypassing unqualified lookup and ASTScope altogether.
if (dc->isModuleScopeContext())
loc = SourceLoc();
DirectlyReferencedTypeDecls results;
UnqualifiedLookupOptions options =
UnqualifiedLookupFlags::TypeLookup |
UnqualifiedLookupFlags::AllowProtocolMembers;
if (lookupOuter == LookupOuterResults::Included)
options |= UnqualifiedLookupFlags::IncludeOuterResults;
auto &ctx = dc->getASTContext();
auto descriptor = UnqualifiedLookupDescriptor(name, dc, loc, options);
auto lookup = evaluateOrDefault(ctx.evaluator,
UnqualifiedLookupRequest{descriptor}, {});
for (const auto &result : lookup.allResults()) {
auto typeDecl = cast<TypeDecl>(result.getValueDecl());
results.push_back(typeDecl);
}
return results;
}
/// Perform qualified name lookup for types.
static DirectlyReferencedTypeDecls
directReferencesForQualifiedTypeLookup(Evaluator &evaluator,
ASTContext &ctx,
ArrayRef<TypeDecl *> baseTypes,
DeclNameRef name,
DeclContext *dc) {
DirectlyReferencedTypeDecls result;
auto addResults = [&result](ArrayRef<ValueDecl *> found){
for (auto decl : found){
assert(isa<TypeDecl>(decl) &&
"Lookup should only have found type declarations");
result.push_back(cast<TypeDecl>(decl));
}
};
{
// Look into the base types.
SmallVector<ValueDecl *, 4> members;
auto options = NL_RemoveNonVisible | NL_OnlyTypes;
// Look through the type declarations we were given, resolving them down
// to nominal type declarations, module declarations, and
SmallVector<ModuleDecl *, 2> moduleDecls;
bool anyObject = false;
auto nominalTypeDecls =
resolveTypeDeclsToNominal(ctx.evaluator, ctx, baseTypes, moduleDecls,
anyObject);
dc->lookupQualified(nominalTypeDecls, name, options, members);
// Search all of the modules.
for (auto module : moduleDecls) {
auto innerOptions = options;
innerOptions &= ~NL_RemoveOverridden;
innerOptions &= ~NL_RemoveNonVisible;
SmallVector<ValueDecl *, 4> moduleMembers;
dc->lookupQualified(module, name, innerOptions, moduleMembers);
members.append(moduleMembers.begin(), moduleMembers.end());
}
addResults(members);
}
return result;
}
/// Determine the types directly referenced by the given identifier type.
static DirectlyReferencedTypeDecls
directReferencesForIdentTypeRepr(Evaluator &evaluator,
ASTContext &ctx, IdentTypeRepr *ident,
DeclContext *dc) {
DirectlyReferencedTypeDecls current;
bool firstComponent = true;
for (const auto &component : ident->getComponentRange()) {
// If we already set a declaration, use it.
if (auto typeDecl = component->getBoundDecl()) {
current = {1, typeDecl};
continue;
}
// For the first component, perform unqualified name lookup.
if (current.empty()) {
current =
directReferencesForUnqualifiedTypeLookup(component->getNameRef(),
component->getLoc(),
dc,
LookupOuterResults::Excluded);
// If we didn't find anything, fail now.
if (current.empty())
return current;
firstComponent = false;
continue;
}
// For subsequent components, perform qualified name lookup.
current =
directReferencesForQualifiedTypeLookup(evaluator, ctx, current,
component->getNameRef(), dc);
if (current.empty())
return current;
}
return current;
}
static DirectlyReferencedTypeDecls
directReferencesForTypeRepr(Evaluator &evaluator,
ASTContext &ctx, TypeRepr *typeRepr,
DeclContext *dc) {
switch (typeRepr->getKind()) {
case TypeReprKind::Array:
return {1, ctx.getArrayDecl()};
case TypeReprKind::Attributed: {
auto attributed = cast<AttributedTypeRepr>(typeRepr);
return directReferencesForTypeRepr(evaluator, ctx,
attributed->getTypeRepr(), dc);
}
case TypeReprKind::Composition: {
DirectlyReferencedTypeDecls result;
auto composition = cast<CompositionTypeRepr>(typeRepr);
for (auto component : composition->getTypes()) {
auto componentResult =
directReferencesForTypeRepr(evaluator, ctx, component, dc);
result.insert(result.end(),
componentResult.begin(),
componentResult.end());
}
return result;
}
case TypeReprKind::CompoundIdent:
case TypeReprKind::GenericIdent:
case TypeReprKind::SimpleIdent:
return directReferencesForIdentTypeRepr(evaluator, ctx,
cast<IdentTypeRepr>(typeRepr), dc);
case TypeReprKind::Dictionary:
return { 1, ctx.getDictionaryDecl()};
case TypeReprKind::Tuple: {
auto tupleRepr = cast<TupleTypeRepr>(typeRepr);
if (tupleRepr->isParenType()) {
return directReferencesForTypeRepr(evaluator, ctx,
tupleRepr->getElementType(0), dc);
}
return { };
}
case TypeReprKind::Error:
case TypeReprKind::Function:
case TypeReprKind::InOut:
case TypeReprKind::Metatype:
case TypeReprKind::Owned:
case TypeReprKind::Protocol:
case TypeReprKind::Shared:
case TypeReprKind::SILBox:
return { };
case TypeReprKind::OpaqueReturn:
return { };
case TypeReprKind::Fixed:
llvm_unreachable("Cannot get fixed TypeReprs in name lookup");
case TypeReprKind::Optional:
case TypeReprKind::ImplicitlyUnwrappedOptional:
return { 1, ctx.getOptionalDecl() };
}
llvm_unreachable("unhandled kind");
}
static DirectlyReferencedTypeDecls directReferencesForType(Type type) {
// If it's a typealias, return that.
if (auto aliasType = dyn_cast<TypeAliasType>(type.getPointer()))
return { 1, aliasType->getDecl() };
// If there is a generic declaration, return it.
if (auto genericDecl = type->getAnyGeneric())
return { 1, genericDecl };
if (type->isExistentialType()) {
DirectlyReferencedTypeDecls result;
const auto &layout = type->getExistentialLayout();
// Superclass.
if (auto superclassType = layout.explicitSuperclass) {
if (auto superclassDecl = superclassType->getAnyGeneric()) {
result.push_back(superclassDecl);
}
}
// Protocols.
for (auto protocolTy : layout.getProtocols())
result.push_back(protocolTy->getDecl());
return result;
}
return { };
}
DirectlyReferencedTypeDecls InheritedDeclsReferencedRequest::evaluate(
Evaluator &evaluator,
llvm::PointerUnion<const TypeDecl *, const ExtensionDecl *> decl,
unsigned index) const {
// Prefer syntactic information when we have it.
const TypeLoc &typeLoc = getInheritedTypeLocAtIndex(decl, index);
if (auto typeRepr = typeLoc.getTypeRepr()) {
// Figure out the context in which name lookup will occur.
DeclContext *dc;
if (auto typeDecl = decl.dyn_cast<const TypeDecl *>())
dc = typeDecl->getInnermostDeclContext();
else
dc = (DeclContext *)decl.get<const ExtensionDecl *>();
return directReferencesForTypeRepr(evaluator, dc->getASTContext(), typeRepr,
const_cast<DeclContext *>(dc));
}
// Fall back to semantic types.
// FIXME: In the long run, we shouldn't need this. Non-syntactic results
// should be cached.
if (auto type = typeLoc.getType()) {
return directReferencesForType(type);
}
return { };
}
DirectlyReferencedTypeDecls UnderlyingTypeDeclsReferencedRequest::evaluate(
Evaluator &evaluator,
TypeAliasDecl *typealias) const {
// Prefer syntactic information when we have it.
if (auto typeRepr = typealias->getUnderlyingTypeRepr()) {
return directReferencesForTypeRepr(evaluator, typealias->getASTContext(),
typeRepr, typealias);
}
// Fall back to semantic types.
// FIXME: In the long run, we shouldn't need this. Non-syntactic results
// should be cached.
if (auto type = typealias->getUnderlyingType()) {
return directReferencesForType(type);
}
return { };
}
/// Evaluate a superclass declaration request.
ClassDecl *
SuperclassDeclRequest::evaluate(Evaluator &evaluator,
NominalTypeDecl *subject) const {
auto &Ctx = subject->getASTContext();
// Protocols may get their superclass bound from a `where Self : Superclass`
// clause.
if (auto *proto = dyn_cast<ProtocolDecl>(subject)) {
// If the protocol came from a serialized module, compute the superclass via
// its generic signature.
if (proto->wasDeserialized()) {
auto superTy = proto->getGenericSignature()
->getSuperclassBound(proto->getSelfInterfaceType());
if (superTy)
return superTy->getClassOrBoundGenericClass();
}
// Otherwise check the where clause.
auto selfBounds = getSelfBoundsFromWhereClause(proto);
for (auto inheritedNominal : selfBounds.decls)
if (auto classDecl = dyn_cast<ClassDecl>(inheritedNominal))
return classDecl;
}
for (unsigned i : indices(subject->getInherited())) {
// Find the inherited declarations referenced at this position.
auto inheritedTypes = evaluateOrDefault(evaluator,
InheritedDeclsReferencedRequest{subject, i}, {});
// Resolve those type declarations to nominal type declarations.
SmallVector<ModuleDecl *, 2> modulesFound;
bool anyObject = false;
auto inheritedNominalTypes
= resolveTypeDeclsToNominal(evaluator, Ctx,
inheritedTypes, modulesFound, anyObject);
// Look for a class declaration.
ClassDecl *superclass = nullptr;
for (auto inheritedNominal : inheritedNominalTypes) {
if (auto classDecl = dyn_cast<ClassDecl>(inheritedNominal)) {
superclass = classDecl;
break;
}
}
// If we found a superclass, ensure that we don't have a circular
// inheritance hierarchy by evaluating its superclass. This forces the
// diagnostic at this point and then suppresses the superclass failure.
if (superclass) {
auto result = Ctx.evaluator(SuperclassDeclRequest{superclass});
bool hadCycle = false;
if (auto err = result.takeError()) {
llvm::handleAllErrors(std::move(err),
[&hadCycle](const CyclicalRequestError<SuperclassDeclRequest> &E) {
hadCycle = true;
});
if (hadCycle)
return nullptr;
}
return superclass;
}
}
return nullptr;
}
ArrayRef<ProtocolDecl *>
InheritedProtocolsRequest::evaluate(Evaluator &evaluator,
ProtocolDecl *PD) const {
llvm::SmallVector<ProtocolDecl *, 2> result;
SmallPtrSet<const ProtocolDecl *, 2> known;
known.insert(PD);
bool anyObject = false;
for (const auto &found : getDirectlyInheritedNominalTypeDecls(PD, anyObject)) {
if (auto proto = dyn_cast<ProtocolDecl>(found.Item)) {
if (known.insert(proto).second)
result.push_back(proto);
}
}
return PD->getASTContext().AllocateCopy(result);
}
NominalTypeDecl *
ExtendedNominalRequest::evaluate(Evaluator &evaluator,
ExtensionDecl *ext) const {
auto typeRepr = ext->getExtendedTypeRepr();
if (!typeRepr)
// We must've seen 'extension { ... }' during parsing.
return nullptr;
ASTContext &ctx = ext->getASTContext();
DirectlyReferencedTypeDecls referenced =
directReferencesForTypeRepr(evaluator, ctx, typeRepr, ext->getParent());
// Resolve those type declarations to nominal type declarations.
SmallVector<ModuleDecl *, 2> modulesFound;
bool anyObject = false;
auto nominalTypes
= resolveTypeDeclsToNominal(evaluator, ctx, referenced, modulesFound,
anyObject);
// If there is more than 1 element, we will emit a warning or an error
// elsewhere, so don't handle that case here.
return nominalTypes.empty() ? nullptr : nominalTypes[0];
}
/// Whether there are only associated types in the set of declarations.
static bool declsAreAssociatedTypes(ArrayRef<TypeDecl *> decls) {
if (decls.empty())
return false;
for (auto decl : decls) {
if (!isa<AssociatedTypeDecl>(decl))
return false;
}
return true;
}
static GenericParamList *
createExtensionGenericParams(ASTContext &ctx,
ExtensionDecl *ext,
NominalTypeDecl *nominal) {
// Collect generic parameters from all outer contexts.
SmallVector<GenericParamList *, 2> allGenericParams;
nominal->forEachGenericContext([&](GenericParamList *gpList) {
allGenericParams.push_back(gpList->clone(ext));
});
GenericParamList *toParams = nullptr;
for (auto *gpList : llvm::reverse(allGenericParams)) {
gpList->setOuterParameters(toParams);
toParams = gpList;
}
return toParams;
}
GenericParamList *
GenericParamListRequest::evaluate(Evaluator &evaluator, GenericContext *value) const {
if (auto *ext = dyn_cast<ExtensionDecl>(value)) {
// Create the generic parameter list for the extension by cloning the
// generic parameter lists of the nominal and any of its parent types.
auto &ctx = value->getASTContext();
auto *nominal = ext->getExtendedNominal();
if (!nominal) {
return nullptr;
}
auto *genericParams = createExtensionGenericParams(ctx, ext, nominal);
// Protocol extensions need an inheritance clause due to how name lookup
// is implemented.
if (auto *proto = ext->getExtendedProtocolDecl()) {
auto protoType = proto->getDeclaredInterfaceType();
TypeLoc selfInherited[1] = { TypeLoc::withoutLoc(protoType) };
genericParams->getParams().front()->setInherited(
ctx.AllocateCopy(selfInherited));
}
// Set the depth of every generic parameter.
unsigned depth = nominal->getGenericContextDepth();
for (auto *outerParams = genericParams;
outerParams != nullptr;
outerParams = outerParams->getOuterParameters())
outerParams->setDepth(depth--);
return genericParams;
} else if (auto *proto = dyn_cast<ProtocolDecl>(value)) {
// The generic parameter 'Self'.
auto &ctx = value->getASTContext();
auto selfId = ctx.Id_Self;
auto selfDecl = new (ctx) GenericTypeParamDecl(
proto, selfId, SourceLoc(), /*depth=*/0, /*index=*/0);
auto protoType = proto->getDeclaredInterfaceType();
TypeLoc selfInherited[1] = { TypeLoc::withoutLoc(protoType) };
selfDecl->setInherited(ctx.AllocateCopy(selfInherited));
selfDecl->setImplicit();
// The generic parameter list itself.
auto result = GenericParamList::create(ctx, SourceLoc(), selfDecl,
SourceLoc());
return result;
}
return nullptr;
}
NominalTypeDecl *
CustomAttrNominalRequest::evaluate(Evaluator &evaluator,
CustomAttr *attr, DeclContext *dc) const {
// Find the types referenced by the custom attribute.
auto &ctx = dc->getASTContext();
DirectlyReferencedTypeDecls decls;
if (auto *typeRepr = attr->getTypeRepr()) {
decls = directReferencesForTypeRepr(
evaluator, ctx, typeRepr, dc);
} else if (Type type = attr->getType()) {
decls = directReferencesForType(type);
}
// Dig out the nominal type declarations.
SmallVector<ModuleDecl *, 2> modulesFound;
bool anyObject = false;
auto nominals = resolveTypeDeclsToNominal(evaluator, ctx, decls,
modulesFound, anyObject);
if (nominals.size() == 1 && !isa<ProtocolDecl>(nominals.front()))
return nominals.front();
// If we found declarations that are associated types, look outside of
// the current context to see if we can recover.
if (declsAreAssociatedTypes(decls)) {
if (auto typeRepr = attr->getTypeRepr()) {
if (auto identTypeRepr = dyn_cast<SimpleIdentTypeRepr>(typeRepr)) {
auto assocType = cast<AssociatedTypeDecl>(decls.front());
modulesFound.clear();
anyObject = false;
decls = directReferencesForUnqualifiedTypeLookup(
identTypeRepr->getNameRef(), identTypeRepr->getLoc(), dc,
LookupOuterResults::Included);
nominals = resolveTypeDeclsToNominal(evaluator, ctx, decls,
modulesFound, anyObject);
if (nominals.size() == 1 && !isa<ProtocolDecl>(nominals.front())) {
auto nominal = nominals.front();
if (nominal->getDeclContext()->isModuleScopeContext()) {
// Complain, producing module qualification in a Fix-It.
auto moduleName = nominal->getParentModule()->getName();
ctx.Diags.diagnose(typeRepr->getLoc(),
diag::warn_property_wrapper_module_scope,
identTypeRepr->getNameRef(),
moduleName)
.fixItInsert(typeRepr->getLoc(),
moduleName.str().str() + ".");
ctx.Diags.diagnose(assocType, diag::kind_declname_declared_here,
assocType->getDescriptiveKind(),
assocType->getName());
ComponentIdentTypeRepr *components[2] = {
new (ctx) SimpleIdentTypeRepr(identTypeRepr->getNameLoc(),
DeclNameRef(moduleName)),
identTypeRepr
};
auto *newTE = new (ctx) TypeExpr(IdentTypeRepr::create(ctx, components));
attr->resetTypeInformation(newTE);
return nominal;
}
}
}
}
}
// If we have more than one attribute declaration, we have an ambiguity.
// So, emit an ambiguity diagnostic.
if (auto typeRepr = attr->getTypeRepr()) {
if (nominals.size() > 1) {
SmallVector<NominalTypeDecl *, 4> ambiguousCandidates;
// Filter out declarations that cannot be attributes.
for (auto decl : nominals) {
if (isa<ProtocolDecl>(decl)) {
continue;
}
ambiguousCandidates.push_back(decl);
}
if (ambiguousCandidates.size() > 1) {
auto attrName = nominals.front()->getName();
ctx.Diags.diagnose(typeRepr->getLoc(),
diag::ambiguous_custom_attribute_ref, attrName);
for (auto candidate : ambiguousCandidates) {
ctx.Diags.diagnose(candidate->getLoc(),
diag::found_attribute_candidate);
// If the candidate is a top-level attribute, let's suggest
// adding module name to resolve the ambiguity.
if (candidate->getDeclContext()->isModuleScopeContext()) {
auto moduleName = candidate->getParentModule()->getName();
ctx.Diags
.diagnose(typeRepr->getLoc(),
diag::ambiguous_custom_attribute_ref_fix,
moduleName.str(), attrName, moduleName)
.fixItInsert(typeRepr->getLoc(), moduleName.str().str() + ".");
}
}
return nullptr;
}
}
}
// There is no nominal type with this name, so complain about this being
// an unknown attribute.
std::string typeName;
if (auto typeRepr = attr->getTypeRepr()) {
llvm::raw_string_ostream out(typeName);
typeRepr->print(out);
} else {
typeName = attr->getType().getString();
}
ctx.Diags.diagnose(attr->getLocation(), diag::unknown_attribute, typeName);
return nullptr;
}
void swift::getDirectlyInheritedNominalTypeDecls(
llvm::PointerUnion<const TypeDecl *, const ExtensionDecl *> decl,
unsigned i, llvm::SmallVectorImpl<Located<NominalTypeDecl *>> &result,
bool &anyObject) {
auto typeDecl = decl.dyn_cast<const TypeDecl *>();
auto extDecl = decl.dyn_cast<const ExtensionDecl *>();
ASTContext &ctx = typeDecl ? typeDecl->getASTContext()
: extDecl->getASTContext();
// Find inherited declarations.
auto referenced = evaluateOrDefault(ctx.evaluator,
InheritedDeclsReferencedRequest{decl, i}, {});
// Resolve those type declarations to nominal type declarations.
SmallVector<ModuleDecl *, 2> modulesFound;
auto nominalTypes
= resolveTypeDeclsToNominal(ctx.evaluator, ctx, referenced, modulesFound,
anyObject);
// Dig out the source location
// FIXME: This is a hack. We need cooperation from
// InheritedDeclsReferencedRequest to make this work.
SourceLoc loc;
if (TypeRepr *typeRepr = typeDecl ? typeDecl->getInherited()[i].getTypeRepr()
: extDecl->getInherited()[i].getTypeRepr()){
loc = typeRepr->getLoc();
}
// Form the result.
for (auto nominal : nominalTypes) {
result.push_back({nominal, loc});
}
}
SmallVector<Located<NominalTypeDecl *>, 4>
swift::getDirectlyInheritedNominalTypeDecls(
llvm::PointerUnion<const TypeDecl *, const ExtensionDecl *> decl,
bool &anyObject) {
auto typeDecl = decl.dyn_cast<const TypeDecl *>();
auto extDecl = decl.dyn_cast<const ExtensionDecl *>();
// Gather results from all of the inherited types.
unsigned numInherited = typeDecl ? typeDecl->getInherited().size()
: extDecl->getInherited().size();
SmallVector<Located<NominalTypeDecl *>, 4> result;
for (unsigned i : range(numInherited)) {
getDirectlyInheritedNominalTypeDecls(decl, i, result, anyObject);
}
auto *protoDecl = dyn_cast_or_null<ProtocolDecl>(typeDecl);
if (protoDecl == nullptr)
return result;
// FIXME: Refactor SelfBoundsFromWhereClauseRequest to dig out
// the source location.
SourceLoc loc = SourceLoc();
// For a deserialized protocol, the where clause isn't going to tell us
// anything. Ask the requirement signature instead.
if (protoDecl->wasDeserialized()) {
auto protoSelfTy = protoDecl->getSelfInterfaceType();
for (auto &req : protoDecl->getRequirementSignature()) {
// Dig out a conformance requirement...
if (req.getKind() != RequirementKind::Conformance)
continue;
// constraining Self.
if (!req.getFirstType()->isEqual(protoSelfTy))
continue;
result.emplace_back(req.getSecondType()->castTo<ProtocolType>()->getDecl(),
loc);
}
return result;
}
// Else we have access to this information on the where clause.
auto selfBounds = getSelfBoundsFromWhereClause(decl);
anyObject |= selfBounds.anyObject;
for (auto inheritedNominal : selfBounds.decls)
result.emplace_back(inheritedNominal, loc);
return result;
}
void FindLocalVal::checkPattern(const Pattern *Pat, DeclVisibilityKind Reason) {
switch (Pat->getKind()) {
case PatternKind::Tuple:
for (auto &field : cast<TuplePattern>(Pat)->getElements())
checkPattern(field.getPattern(), Reason);
return;
case PatternKind::Paren:
case PatternKind::Typed:
case PatternKind::Binding:
return checkPattern(Pat->getSemanticsProvidingPattern(), Reason);
case PatternKind::Named:
return checkValueDecl(cast<NamedPattern>(Pat)->getDecl(), Reason);
case PatternKind::EnumElement: {
auto *OP = cast<EnumElementPattern>(Pat);
if (OP->hasSubPattern())
checkPattern(OP->getSubPattern(), Reason);
return;
}
case PatternKind::OptionalSome:
checkPattern(cast<OptionalSomePattern>(Pat)->getSubPattern(), Reason);
return;
case PatternKind::Is: {
auto *isPat = cast<IsPattern>(Pat);
if (isPat->hasSubPattern())
checkPattern(isPat->getSubPattern(), Reason);
return;
}
// Handle non-vars.
case PatternKind::Bool:
case PatternKind::Expr:
case PatternKind::Any:
return;
}
}
void FindLocalVal::checkParameterList(const ParameterList *params) {
for (auto param : *params) {
checkValueDecl(param, DeclVisibilityKind::FunctionParameter);
}
}
void FindLocalVal::checkGenericParams(GenericParamList *Params) {
if (!Params)
return;
for (auto P : *Params)
checkValueDecl(P, DeclVisibilityKind::GenericParameter);
}
void FindLocalVal::checkSourceFile(const SourceFile &SF) {
for (Decl *D : SF.getTopLevelDecls())
if (auto *TLCD = dyn_cast<TopLevelCodeDecl>(D))
visitBraceStmt(TLCD->getBody(), /*isTopLevel=*/true);
}
void FindLocalVal::checkStmtCondition(const StmtCondition &Cond) {
SourceLoc start = SourceLoc();
for (auto entry : Cond) {
if (start.isInvalid())
start = entry.getStartLoc();
if (auto *P = entry.getPatternOrNull()) {
SourceRange previousConditionsToHere = SourceRange(start, entry.getEndLoc());
if (!isReferencePointInRange(previousConditionsToHere))
checkPattern(P, DeclVisibilityKind::LocalVariable);
}
}
}
void FindLocalVal::visitIfStmt(IfStmt *S) {
if (!isReferencePointInRange(S->getSourceRange()))
return;
if (!S->getElseStmt() ||
!isReferencePointInRange(S->getElseStmt()->getSourceRange())) {
checkStmtCondition(S->getCond());
}
visit(S->getThenStmt());
if (S->getElseStmt())
visit(S->getElseStmt());
}
void FindLocalVal::visitGuardStmt(GuardStmt *S) {
if (SM.isBeforeInBuffer(Loc, S->getStartLoc()))
return;
// Names in the guard aren't visible until after the body.
if (S->getBody()->isImplicit() ||
!isReferencePointInRange(S->getBody()->getSourceRange()))
checkStmtCondition(S->getCond());
visit(S->getBody());
}
void FindLocalVal::visitWhileStmt(WhileStmt *S) {
if (!isReferencePointInRange(S->getSourceRange()))
return;
checkStmtCondition(S->getCond());
visit(S->getBody());
}
void FindLocalVal::visitRepeatWhileStmt(RepeatWhileStmt *S) {
visit(S->getBody());
}
void FindLocalVal::visitDoStmt(DoStmt *S) {
visit(S->getBody());
}
void FindLocalVal::visitForEachStmt(ForEachStmt *S) {
if (!isReferencePointInRange(S->getSourceRange()))
return;
visit(S->getBody());
if (!isReferencePointInRange(S->getSequence()->getSourceRange()))
checkPattern(S->getPattern(), DeclVisibilityKind::LocalVariable);
}
void FindLocalVal::visitBraceStmt(BraceStmt *S, bool isTopLevelCode) {
if (isTopLevelCode) {
if (SM.isBeforeInBuffer(Loc, S->getStartLoc()))
return;
} else {
if (!isReferencePointInRange(S->getSourceRange()))
return;
}
for (auto elem : S->getElements()) {
if (auto *S = elem.dyn_cast<Stmt*>())
visit(S);
}
for (auto elem : S->getElements()) {
if (auto *D = elem.dyn_cast<Decl*>()) {
if (auto *VD = dyn_cast<ValueDecl>(D))
checkValueDecl(VD, DeclVisibilityKind::LocalVariable);
}
}
}
void FindLocalVal::visitSwitchStmt(SwitchStmt *S) {
if (!isReferencePointInRange(S->getSourceRange()))
return;
for (CaseStmt *C : S->getCases()) {
visit(C);
}
}
void FindLocalVal::visitCaseStmt(CaseStmt *S) {
if (!isReferencePointInRange(S->getSourceRange()))
return;
// Pattern names aren't visible in the patterns themselves,
// just in the body or in where guards.
bool inPatterns = isReferencePointInRange(S->getLabelItemsRange());
auto items = S->getCaseLabelItems();
if (inPatterns) {
for (const auto &CLI : items) {
auto guard = CLI.getGuardExpr();
if (guard && isReferencePointInRange(guard->getSourceRange())) {
checkPattern(CLI.getPattern(), DeclVisibilityKind::LocalVariable);
break;
}
}
}
if (!inPatterns && !items.empty()) {
for (auto *vd : S->getCaseBodyVariablesOrEmptyArray()) {
checkValueDecl(vd, DeclVisibilityKind::LocalVariable);
}
}
visit(S->getBody());
}
void FindLocalVal::visitDoCatchStmt(DoCatchStmt *S) {
if (!isReferencePointInRange(S->getSourceRange()))
return;
visit(S->getBody());
for (CaseStmt *C : S->getCatches()) {
visit(C);
}
}
void swift::simple_display(llvm::raw_ostream &out, NLKind kind) {
switch (kind) {
case NLKind::QualifiedLookup:
out << "QualifiedLookup";
return;
case NLKind::UnqualifiedLookup:
out << "UnqualifiedLookup";
return;
}
llvm_unreachable("Unhandled case in switch");
}
void swift::simple_display(llvm::raw_ostream &out, NLOptions options) {
using Flag = std::pair<NLOptions, StringRef>;
Flag possibleFlags[] = {
#define FLAG(Name) {Name, #Name},
FLAG(NL_ProtocolMembers)
FLAG(NL_RemoveNonVisible)
FLAG(NL_RemoveOverridden)
FLAG(NL_IgnoreAccessControl)
FLAG(NL_OnlyTypes)
FLAG(NL_IncludeAttributeImplements)
#undef FLAG
};
auto flagsToPrint = llvm::make_filter_range(
possibleFlags, [&](Flag flag) { return options & flag.first; });
out << "{ ";
interleave(
flagsToPrint, [&](Flag flag) { out << flag.second; },
[&] { out << ", "; });
out << " }";
}