Files
swift-mirror/lib/IRGen/GenReflection.cpp
Doug Gregor b531b3923f [ABI] Use mangled names for associated type witnesses.
Rather than storing associated type metadata access functions in
witness tables, initially store a pointer to a mangled type name.
On first access, demangle that type name and replace the witness
table entry with the resulting type metadata.

This reduces the code size of protocol conformances, because we no
longer need to create associated type metadata access functions for
every associated type, and the mangled names are much smaller (and
sharable). The same code size improvements apply to defaulted
associated types for resilient protocols, although those are more
rare. Witness tables themselves are slightly smaller, because we
don’t need separate private entries in them to act as caches.

On the caller side, associated type metadata is always produced via
a call to swift_getAssociatedTypeWitness(), which handles the demangling
and caching behavior.

In all, this reduces the size of the standard library by ~70k. There
are additional code-size wins that are possible with follow-on work:

* We can stop emitting type metadata access functions for non-resilient
types that have constant metadata (like `Int`), because they’re only
currently used as associated type metadata access functions.
* We can stop emitting separate associated type reflection metadata,
because the reflection infrastructure can use these mangled names
directly.
2018-09-26 23:19:33 -07:00

987 lines
31 KiB
C++

//===--- GenReflection.cpp - IR generation for nominal type reflection ----===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2017 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 IR generation of type metadata for struct/class
// stored properties and enum cases for use with reflection.
//===----------------------------------------------------------------------===//
#include "swift/AST/Decl.h"
#include "swift/AST/IRGenOptions.h"
#include "swift/AST/PrettyStackTrace.h"
#include "swift/AST/ProtocolConformance.h"
#include "swift/AST/SubstitutionMap.h"
#include "swift/IRGen/Linking.h"
#include "swift/Reflection/MetadataSourceBuilder.h"
#include "swift/Reflection/Records.h"
#include "swift/SIL/SILModule.h"
#include "ConstantBuilder.h"
#include "GenClass.h"
#include "GenDecl.h"
#include "GenEnum.h"
#include "GenHeap.h"
#include "GenProto.h"
#include "GenType.h"
#include "IRGenMangler.h"
#include "IRGenModule.h"
#include "LoadableTypeInfo.h"
using namespace swift;
using namespace irgen;
using namespace reflection;
class MetadataSourceEncoder
: public MetadataSourceVisitor<MetadataSourceEncoder> {
llvm::raw_ostream &OS;
public:
MetadataSourceEncoder(llvm::raw_ostream &OS) : OS(OS) {}
void
visitClosureBindingMetadataSource(const ClosureBindingMetadataSource *CB) {
OS << 'B';
OS << CB->getIndex();
}
void
visitReferenceCaptureMetadataSource(const ReferenceCaptureMetadataSource *RC){
OS << 'R';
OS << RC->getIndex();
}
void
visitMetadataCaptureMetadataSource(const MetadataCaptureMetadataSource *MC) {
OS << 'M';
OS << MC->getIndex();
}
void
visitGenericArgumentMetadataSource(const GenericArgumentMetadataSource *GA) {
OS << 'G';
OS << GA->getIndex();
visit(GA->getSource());
OS << '_';
}
void visitSelfMetadataSource(const SelfMetadataSource *S) {
OS << 'S';
}
void
visitSelfWitnessTableMetadataSource(const SelfWitnessTableMetadataSource *S) {
OS << 'W';
}
};
class PrintMetadataSource
: public MetadataSourceVisitor<PrintMetadataSource, void> {
llvm::raw_ostream &OS;
unsigned Indent;
llvm::raw_ostream &indent(unsigned Amount) {
for (unsigned i = 0; i < Amount; ++i)
OS << ' ';
return OS;
}
llvm::raw_ostream &printHeader(std::string Name) {
indent(Indent) << '(' << Name;
return OS;
}
template<typename T>
llvm::raw_ostream &printField(std::string name, const T &value) {
if (!name.empty())
OS << " " << name << "=" << value;
else
OS << " " << value;
return OS;
}
void printRec(const reflection::MetadataSource *MS) {
OS << "\n";
Indent += 2;
visit(MS);
Indent -= 2;
}
void closeForm() {
OS << ')';
}
public:
PrintMetadataSource(llvm::raw_ostream &OS, unsigned Indent)
: OS(OS), Indent(Indent) {}
void
visitClosureBindingMetadataSource(const ClosureBindingMetadataSource *CB) {
printHeader("closure-binding");
printField("index", CB->getIndex());
closeForm();
}
void
visitReferenceCaptureMetadataSource(const ReferenceCaptureMetadataSource *RC){
printHeader("reference-capture");
printField("index", RC->getIndex());
closeForm();
}
void
visitMetadataCaptureMetadataSource(const MetadataCaptureMetadataSource *MC){
printHeader("metadata-capture");
printField("index", MC->getIndex());
closeForm();
}
void
visitGenericArgumentMetadataSource(const GenericArgumentMetadataSource *GA) {
printHeader("generic-argument");
printField("index", GA->getIndex());
printRec(GA->getSource());
closeForm();
}
void
visitSelfMetadataSource(const SelfMetadataSource *S) {
printHeader("self");
closeForm();
}
void
visitSelfWitnessTableMetadataSource(const SelfWitnessTableMetadataSource *S) {
printHeader("self-witness-table");
closeForm();
}
};
llvm::Constant *IRGenModule::getTypeRef(CanType type, unsigned alignment) {
IRGenMangler Mangler;
auto SymbolicName = Mangler.mangleTypeForReflection(*this, type);
return getAddrOfStringForTypeRef(SymbolicName, alignment);
}
class ReflectionMetadataBuilder {
protected:
IRGenModule &IGM;
ConstantInitBuilder InitBuilder;
ConstantStructBuilder B;
ReflectionMetadataBuilder(IRGenModule &IGM)
: IGM(IGM), InitBuilder(IGM), B(InitBuilder.beginStruct()) {}
virtual ~ReflectionMetadataBuilder() {}
// Collect any builtin types referenced from this type.
void addBuiltinTypeRefs(CanType type) {
type.visit([&](CanType t) {
if (IGM.getSwiftModule()->isStdlibModule() && isa<BuiltinType>(t))
IGM.BuiltinTypes.insert(t);
// We need size/alignment information for imported value types,
// so emit builtin descriptors for them.
//
// In effect they're treated like an opaque blob, which is OK
// for now, at least until we want to import C++ types or
// something like that.
//
// Classes and protocols go down a different path.
if (auto Nominal = t->getAnyNominal())
if (Nominal->hasClangNode()) {
if (auto CD = dyn_cast<ClassDecl>(Nominal))
IGM.ImportedClasses.insert(CD);
else if (auto PD = dyn_cast<ProtocolDecl>(Nominal))
IGM.ImportedProtocols.insert(PD);
else
IGM.OpaqueTypes.insert(Nominal);
}
});
}
/// Add a 32-bit relative offset to a mangled typeref string
/// in the typeref reflection section.
void addTypeRef(CanType type) {
B.addRelativeAddress(IGM.getTypeRef(type));
}
/// Add a 32-bit relative offset to a mangled nominal type string
/// in the typeref reflection section.
void addNominalRef(const NominalTypeDecl *nominal) {
if (auto proto = dyn_cast<ProtocolDecl>(nominal)) {
IRGenMangler mangler;
SymbolicMangling mangledStr;
mangledStr.String = mangler.mangleBareProtocol(proto);
auto mangledName = IGM.getAddrOfStringForTypeRef(mangledStr);
B.addRelativeAddress(mangledName);
} else {
CanType type = nominal->getDeclaredType()->getCanonicalType();
B.addRelativeAddress(IGM.getTypeRef(type));
}
}
// A function signature for a lambda wrapping an IRGenModule::getAddrOf*
// method.
using GetAddrOfEntityFn = llvm::Constant* (IRGenModule &, ConstantInit);
llvm::GlobalVariable *emit(
Optional<llvm::function_ref<GetAddrOfEntityFn>> getAddr,
const char *section) {
layout();
llvm::GlobalVariable *var;
// Some reflection records have a mangled symbol name, for uniquing
// imported type metadata.
if (getAddr) {
auto init = B.finishAndCreateFuture();
var = cast<llvm::GlobalVariable>((*getAddr)(IGM, init));
var->setConstant(true);
// Others, such as capture descriptors, do not have a name.
} else {
var = B.finishAndCreateGlobal("\x01l__swift5_reflection_descriptor",
Alignment(4), /*isConstant*/ true,
llvm::GlobalValue::PrivateLinkage);
}
var->setSection(section);
IGM.addUsedGlobal(var);
disableAddressSanitizer(IGM, var);
return var;
}
// Helpers to guide the C++ type system into converting lambda arguments
// to Optional<function_ref>
llvm::GlobalVariable *emit(llvm::function_ref<GetAddrOfEntityFn> getAddr,
const char *section) {
return emit(Optional<llvm::function_ref<GetAddrOfEntityFn>>(getAddr),
section);
}
llvm::GlobalVariable *emit(NoneType none,
const char *section) {
return emit(Optional<llvm::function_ref<GetAddrOfEntityFn>>(),
section);
}
virtual void layout() = 0;
};
class AssociatedTypeMetadataBuilder : public ReflectionMetadataBuilder {
static const uint32_t AssociatedTypeRecordSize = 8;
const ProtocolConformance *Conformance;
ArrayRef<std::pair<StringRef, CanType>> AssociatedTypes;
void layout() override {
// If the conforming type is generic, we just want to emit the
// unbound generic type here.
auto *Nominal = Conformance->getType()->getAnyNominal();
assert(Nominal && "Structural conformance?");
PrettyStackTraceDecl DebugStack("emitting associated type metadata",
Nominal);
addTypeRef(Nominal->getDeclaredType()->getCanonicalType());
addNominalRef(Conformance->getProtocol());
B.addInt32(AssociatedTypes.size());
B.addInt32(AssociatedTypeRecordSize);
for (auto AssocTy : AssociatedTypes) {
auto NameGlobal = IGM.getAddrOfFieldName(AssocTy.first);
B.addRelativeAddress(NameGlobal);
addBuiltinTypeRefs(AssocTy.second);
addTypeRef(AssocTy.second);
}
}
public:
AssociatedTypeMetadataBuilder(IRGenModule &IGM,
const ProtocolConformance *Conformance,
ArrayRef<std::pair<StringRef, CanType>> AssociatedTypes)
: ReflectionMetadataBuilder(IGM), Conformance(Conformance),
AssociatedTypes(AssociatedTypes) {}
llvm::GlobalVariable *emit() {
auto section = IGM.getAssociatedTypeMetadataSectionName();
return ReflectionMetadataBuilder::emit(
[&](IRGenModule &IGM, ConstantInit init) -> llvm::Constant* {
return IGM.getAddrOfReflectionAssociatedTypeDescriptor(Conformance,init);
},
section);
}
};
class FieldTypeMetadataBuilder : public ReflectionMetadataBuilder {
const uint32_t fieldRecordSize = 12;
const NominalTypeDecl *NTD;
void addFieldDecl(const ValueDecl *value, CanType type,
bool indirect=false) {
reflection::FieldRecordFlags flags;
flags.setIsIndirectCase(indirect);
if (auto var = dyn_cast<VarDecl>(value))
flags.setIsVar(!var->isLet());
B.addInt32(flags.getRawValue());
if (!type) {
B.addInt32(0);
} else {
addTypeRef(type);
addBuiltinTypeRefs(type);
}
if (IGM.IRGen.Opts.EnableReflectionNames) {
auto name = value->getBaseName().getIdentifier().str();
auto fieldName = IGM.getAddrOfFieldName(name);
B.addRelativeAddress(fieldName);
} else {
B.addInt32(0);
}
}
void layoutRecord() {
auto kind = FieldDescriptorKind::Struct;
if (auto CD = dyn_cast<ClassDecl>(NTD)) {
auto type = CD->getDeclaredType()->getCanonicalType();
auto RC = type->getReferenceCounting();
if (RC == ReferenceCounting::ObjC)
kind = FieldDescriptorKind::ObjCClass;
else
kind = FieldDescriptorKind::Class;
}
B.addInt16(uint16_t(kind));
B.addInt16(fieldRecordSize);
// Imported classes don't need field descriptors
if (NTD->hasClangNode() && isa<ClassDecl>(NTD)) {
B.addInt32(0);
return;
}
assert(!NTD->hasClangNode() || isa<StructDecl>(NTD));
auto properties = NTD->getStoredProperties();
B.addInt32(std::distance(properties.begin(), properties.end()));
for (auto property : properties)
addFieldDecl(property,
property->getInterfaceType()
->getCanonicalType());
}
void layoutEnum() {
auto enumDecl = cast<EnumDecl>(NTD);
auto &strategy = irgen::getEnumImplStrategy(
IGM, enumDecl->getDeclaredTypeInContext()
->getCanonicalType());
auto kind = FieldDescriptorKind::Enum;
// If this is a fixed-size multi-payload enum, we have to emit a descriptor
// with the size and alignment of the type, because the reflection library
// cannot derive this information at runtime.
if (strategy.getElementsWithPayload().size() > 1 &&
!strategy.needsPayloadSizeInMetadata()) {
kind = FieldDescriptorKind::MultiPayloadEnum;
IGM.OpaqueTypes.insert(enumDecl);
}
B.addInt16(uint16_t(kind));
B.addInt16(fieldRecordSize);
B.addInt32(strategy.getElementsWithPayload().size()
+ strategy.getElementsWithNoPayload().size());
for (auto enumCase : strategy.getElementsWithPayload()) {
bool indirect = (enumCase.decl->isIndirect() ||
enumDecl->isIndirect());
addFieldDecl(enumCase.decl,
enumCase.decl->getArgumentInterfaceType()
->getCanonicalType(),
indirect);
}
for (auto enumCase : strategy.getElementsWithNoPayload()) {
addFieldDecl(enumCase.decl, CanType());
}
}
void layoutProtocol() {
auto protocolDecl = cast<ProtocolDecl>(NTD);
FieldDescriptorKind Kind;
if (protocolDecl->isObjC())
Kind = FieldDescriptorKind::ObjCProtocol;
else if (protocolDecl->requiresClass())
Kind = FieldDescriptorKind::ClassProtocol;
else
Kind = FieldDescriptorKind::Protocol;
B.addInt16(uint16_t(Kind));
B.addInt16(fieldRecordSize);
B.addInt32(0);
}
void layout() override {
if (NTD->hasClangNode() &&
!isa<ClassDecl>(NTD) &&
!isa<StructDecl>(NTD) &&
!isa<ProtocolDecl>(NTD))
return;
PrettyStackTraceDecl DebugStack("emitting field type metadata", NTD);
addNominalRef(NTD);
auto *CD = dyn_cast<ClassDecl>(NTD);
if (CD && CD->getSuperclass()) {
addTypeRef(CD->getSuperclass()->getCanonicalType());
} else {
B.addInt32(0);
}
switch (NTD->getKind()) {
case DeclKind::Class:
case DeclKind::Struct:
layoutRecord();
break;
case DeclKind::Enum:
layoutEnum();
break;
case DeclKind::Protocol:
layoutProtocol();
break;
default:
llvm_unreachable("Not a nominal type");
break;
}
}
public:
FieldTypeMetadataBuilder(IRGenModule &IGM,
const NominalTypeDecl * NTD)
: ReflectionMetadataBuilder(IGM), NTD(NTD) {}
llvm::GlobalVariable *emit() {
auto section = IGM.getFieldTypeMetadataSectionName();
return ReflectionMetadataBuilder::emit(
[&](IRGenModule &IGM, ConstantInit definition) -> llvm::Constant* {
return IGM.getAddrOfReflectionFieldDescriptor(
NTD->getDeclaredType()->getCanonicalType(), definition);
},
section);
}
};
class FixedTypeMetadataBuilder : public ReflectionMetadataBuilder {
ModuleDecl *module;
CanType type;
const FixedTypeInfo *ti;
public:
FixedTypeMetadataBuilder(IRGenModule &IGM,
CanType builtinType)
: ReflectionMetadataBuilder(IGM) {
module = builtinType->getASTContext().TheBuiltinModule;
type = builtinType;
ti = &cast<FixedTypeInfo>(IGM.getTypeInfoForUnlowered(builtinType));
}
FixedTypeMetadataBuilder(IRGenModule &IGM,
const NominalTypeDecl *nominalDecl)
: ReflectionMetadataBuilder(IGM) {
module = nominalDecl->getParentModule();
type = nominalDecl->getDeclaredType()->getCanonicalType();
ti = &cast<FixedTypeInfo>(IGM.getTypeInfoForUnlowered(
nominalDecl->getDeclaredTypeInContext()->getCanonicalType()));
}
void layout() override {
addTypeRef(type);
B.addInt32(ti->getFixedSize().getValue());
B.addInt32(ti->getFixedAlignment().getValue());
B.addInt32(ti->getFixedStride().getValue());
B.addInt32(ti->getFixedExtraInhabitantCount(IGM));
}
llvm::GlobalVariable *emit() {
auto section = IGM.getBuiltinTypeMetadataSectionName();
return ReflectionMetadataBuilder::emit(
[&](IRGenModule &IGM, ConstantInit definition) -> llvm::Constant * {
return IGM.getAddrOfReflectionBuiltinDescriptor(type, definition);
},
section);
}
};
void IRGenModule::emitBuiltinTypeMetadataRecord(CanType builtinType) {
FixedTypeMetadataBuilder builder(*this, builtinType);
builder.emit();
}
void IRGenModule::emitOpaqueTypeMetadataRecord(const NominalTypeDecl *nominalDecl) {
FixedTypeMetadataBuilder builder(*this, nominalDecl);
builder.emit();
}
bool IRGenModule::shouldEmitOpaqueTypeMetadataRecord(
const NominalTypeDecl *nominalDecl) {
if (nominalDecl->getAttrs().hasAttribute<AlignmentAttr>()) {
auto &ti = getTypeInfoForUnlowered(nominalDecl->getDeclaredTypeInContext());
if (isa<FixedTypeInfo>(ti))
return true;
}
return false;
}
/// Builds a constant LLVM struct describing the layout of a fixed-size
/// SIL @box. These look like closure contexts, but without any necessary
/// bindings or metadata sources, and only a single captured value.
class BoxDescriptorBuilder : public ReflectionMetadataBuilder {
CanType BoxedType;
public:
BoxDescriptorBuilder(IRGenModule &IGM, CanType BoxedType)
: ReflectionMetadataBuilder(IGM), BoxedType(BoxedType) {}
void layout() override {
B.addInt32(1);
B.addInt32(0); // Number of sources
B.addInt32(0); // Number of generic bindings
addTypeRef(BoxedType);
addBuiltinTypeRefs(BoxedType);
}
llvm::GlobalVariable *emit() {
auto section = IGM.getCaptureDescriptorMetadataSectionName();
return ReflectionMetadataBuilder::emit(None, section);
}
};
/// Builds a constant LLVM struct describing the layout of a heap closure,
/// the types of its captures, and the sources of metadata if any of the
/// captures are generic.
class CaptureDescriptorBuilder : public ReflectionMetadataBuilder {
swift::reflection::MetadataSourceBuilder SourceBuilder;
CanSILFunctionType OrigCalleeType;
CanSILFunctionType SubstCalleeType;
SubstitutionMap Subs;
const HeapLayout &Layout;
public:
CaptureDescriptorBuilder(IRGenModule &IGM,
CanSILFunctionType OrigCalleeType,
CanSILFunctionType SubstCalleeType,
SubstitutionMap Subs,
const HeapLayout &Layout)
: ReflectionMetadataBuilder(IGM),
OrigCalleeType(OrigCalleeType),
SubstCalleeType(SubstCalleeType), Subs(Subs),
Layout(Layout) {}
using MetadataSourceMap
= std::vector<std::pair<CanType, const reflection::MetadataSource*>>;
void addMetadataSource(const reflection::MetadataSource *Source) {
if (Source == nullptr) {
B.addInt32(0);
} else {
SmallString<16> EncodeBuffer;
llvm::raw_svector_ostream OS(EncodeBuffer);
MetadataSourceEncoder Encoder(OS);
Encoder.visit(Source);
auto EncodedSource = IGM.getAddrOfStringForTypeRef(OS.str());
B.addRelativeAddress(EncodedSource);
}
}
/// Give up if we captured an opened existential type. Eventually we
/// should figure out how to represent this.
static bool hasOpenedExistential(CanSILFunctionType OrigCalleeType,
const HeapLayout &Layout) {
if (!OrigCalleeType->isPolymorphic() ||
OrigCalleeType->isPseudogeneric())
return false;
auto &Bindings = Layout.getBindings();
for (unsigned i = 0; i < Bindings.size(); ++i) {
// Skip protocol requirements (FIXME: for now?)
if (Bindings[i].Protocol != nullptr)
continue;
if (Bindings[i].TypeParameter->hasOpenedExistential())
return true;
}
auto ElementTypes = Layout.getElementTypes().slice(
Layout.hasBindings() ? 1 : 0);
for (auto ElementType : ElementTypes) {
auto SwiftType = ElementType.getASTType();
if (SwiftType->hasOpenedExistential())
return true;
}
return false;
}
/// Slice off the NecessaryBindings struct at the beginning, if it's there.
/// We'll keep track of how many things are in the bindings struct with its
/// own count in the capture descriptor.
ArrayRef<SILType> getElementTypes() {
return Layout.getElementTypes().slice(Layout.hasBindings() ? 1 : 0);
}
/// Build a map from generic parameter -> source of its metadata at runtime.
///
/// If the callee that we are partially applying to create a box/closure
/// isn't generic, then the map is empty.
MetadataSourceMap getMetadataSourceMap() {
MetadataSourceMap SourceMap;
// Generic parameters of pseudogeneric functions do not have
// runtime metadata.
if (!OrigCalleeType->isPolymorphic() ||
OrigCalleeType->isPseudogeneric())
return SourceMap;
// Any generic parameters that are not fulfilled are passed in via the
// bindings. Structural types are decomposed, so emit the contents of
// the bindings structure directly.
auto &Bindings = Layout.getBindings();
for (unsigned i = 0; i < Bindings.size(); ++i) {
// Skip protocol requirements (FIXME: for now?)
if (Bindings[i].Protocol != nullptr)
continue;
auto Source = SourceBuilder.createClosureBinding(i);
auto BindingType = Bindings[i].TypeParameter;
auto InterfaceType = BindingType->mapTypeOutOfContext();
SourceMap.push_back({InterfaceType->getCanonicalType(), Source});
}
// Check if any requirements were fulfilled by metadata stored inside a
// captured value.
enumerateGenericParamFulfillments(IGM, OrigCalleeType,
[&](CanType GenericParam,
const irgen::MetadataSource &Source,
const MetadataPath &Path) {
const reflection::MetadataSource *Root;
switch (Source.getKind()) {
case irgen::MetadataSource::Kind::SelfMetadata:
case irgen::MetadataSource::Kind::SelfWitnessTable:
// Handled as part of bindings
return;
case irgen::MetadataSource::Kind::GenericLValueMetadata:
// FIXME?
return;
case irgen::MetadataSource::Kind::ClassPointer:
Root = SourceBuilder.createReferenceCapture(Source.getParamIndex());
break;
case irgen::MetadataSource::Kind::Metadata:
Root = SourceBuilder.createMetadataCapture(Source.getParamIndex());
break;
}
// The metadata might be reached via a non-trivial path (eg,
// dereferencing an isa pointer or a generic argument). Record
// the path. We assume captured values map 1-1 with function
// parameters.
auto Src = Path.getMetadataSource(SourceBuilder, Root);
auto SubstType = GenericParam.subst(Subs);
auto InterfaceType = SubstType->mapTypeOutOfContext();
SourceMap.push_back({InterfaceType->getCanonicalType(), Src});
});
return SourceMap;
}
/// Get the interface types of all of the captured values, mapped out of the
/// context of the callee we're partially applying.
std::vector<CanType> getCaptureTypes() {
std::vector<CanType> CaptureTypes;
for (auto ElementType : getElementTypes()) {
auto SwiftType = ElementType.getASTType();
// Erase pseudogeneric captures down to AnyObject.
if (OrigCalleeType->isPseudogeneric()) {
SwiftType = SwiftType.transform([&](Type t) -> Type {
if (auto *archetype = t->getAs<ArchetypeType>()) {
assert(archetype->requiresClass() && "don't know what to do");
return IGM.Context.getAnyObjectType();
}
return t;
})->getCanonicalType();
}
auto InterfaceType = SwiftType->mapTypeOutOfContext();
CaptureTypes.push_back(InterfaceType->getCanonicalType());
}
return CaptureTypes;
}
void layout() override {
auto CaptureTypes = getCaptureTypes();
auto MetadataSources = getMetadataSourceMap();
B.addInt32(CaptureTypes.size());
B.addInt32(MetadataSources.size());
B.addInt32(Layout.getBindings().size());
// Now add typerefs of all of the captures.
for (auto CaptureType : CaptureTypes) {
addTypeRef(CaptureType);
addBuiltinTypeRefs(CaptureType);
}
// Add the pairs that make up the generic param -> metadata source map
// to the struct.
for (auto GenericAndSource : MetadataSources) {
auto GenericParam = GenericAndSource.first->getCanonicalType();
auto Source = GenericAndSource.second;
addTypeRef(GenericParam);
addMetadataSource(Source);
}
}
llvm::GlobalVariable *emit() {
auto section = IGM.getCaptureDescriptorMetadataSectionName();
return ReflectionMetadataBuilder::emit(None, section);
}
};
static std::string getReflectionSectionName(IRGenModule &IGM,
StringRef LongName,
StringRef FourCC) {
SmallString<50> SectionName;
llvm::raw_svector_ostream OS(SectionName);
switch (IGM.TargetInfo.OutputObjectFormat) {
case llvm::Triple::UnknownObjectFormat:
llvm_unreachable("unknown object format");
case llvm::Triple::COFF:
assert(FourCC.size() <= 4 &&
"COFF section name length must be <= 8 characters");
OS << ".sw5" << FourCC << "$B";
break;
case llvm::Triple::ELF:
OS << "swift5_" << LongName;
break;
case llvm::Triple::MachO:
assert(LongName.size() <= 7 &&
"Mach-O section name length must be <= 16 characters");
OS << "__TEXT,__swift5_" << LongName << ", regular, no_dead_strip";
break;
case llvm::Triple::Wasm:
llvm_unreachable("web assembly object format is not supported.");
break;
}
return OS.str();
}
const char *IRGenModule::getFieldTypeMetadataSectionName() {
if (FieldTypeSection.empty())
FieldTypeSection = getReflectionSectionName(*this, "fieldmd", "flmd");
return FieldTypeSection.c_str();
}
const char *IRGenModule::getBuiltinTypeMetadataSectionName() {
if (BuiltinTypeSection.empty())
BuiltinTypeSection = getReflectionSectionName(*this, "builtin", "bltn");
return BuiltinTypeSection.c_str();
}
const char *IRGenModule::getAssociatedTypeMetadataSectionName() {
if (AssociatedTypeSection.empty())
AssociatedTypeSection = getReflectionSectionName(*this, "assocty", "asty");
return AssociatedTypeSection.c_str();
}
const char *IRGenModule::getCaptureDescriptorMetadataSectionName() {
if (CaptureDescriptorSection.empty())
CaptureDescriptorSection = getReflectionSectionName(*this, "capture", "cptr");
return CaptureDescriptorSection.c_str();
}
const char *IRGenModule::getReflectionStringsSectionName() {
if (ReflectionStringsSection.empty())
ReflectionStringsSection = getReflectionSectionName(*this, "reflstr", "rfst");
return ReflectionStringsSection.c_str();
}
const char *IRGenModule::getReflectionTypeRefSectionName() {
if (ReflectionTypeRefSection.empty())
ReflectionTypeRefSection = getReflectionSectionName(*this, "typeref", "tyrf");
return ReflectionTypeRefSection.c_str();
}
llvm::Constant *IRGenModule::getAddrOfFieldName(StringRef Name) {
auto &entry = FieldNames[Name];
if (entry.second)
return entry.second;
entry = createStringConstant(Name, /*willBeRelativelyAddressed*/ true,
getReflectionStringsSectionName());
disableAddressSanitizer(*this, entry.first);
return entry.second;
}
llvm::Constant *
IRGenModule::getAddrOfBoxDescriptor(CanType BoxedType) {
if (!IRGen.Opts.EnableReflectionMetadata)
return llvm::Constant::getNullValue(CaptureDescriptorPtrTy);
BoxDescriptorBuilder builder(*this, BoxedType);
auto var = builder.emit();
return llvm::ConstantExpr::getBitCast(var, CaptureDescriptorPtrTy);
}
llvm::Constant *
IRGenModule::getAddrOfCaptureDescriptor(SILFunction &Caller,
CanSILFunctionType OrigCalleeType,
CanSILFunctionType SubstCalleeType,
SubstitutionMap Subs,
const HeapLayout &Layout) {
if (!IRGen.Opts.EnableReflectionMetadata)
return llvm::Constant::getNullValue(CaptureDescriptorPtrTy);
if (CaptureDescriptorBuilder::hasOpenedExistential(OrigCalleeType, Layout))
return llvm::Constant::getNullValue(CaptureDescriptorPtrTy);
CaptureDescriptorBuilder builder(*this,
OrigCalleeType, SubstCalleeType, Subs,
Layout);
auto var = builder.emit();
return llvm::ConstantExpr::getBitCast(var, CaptureDescriptorPtrTy);
}
void IRGenModule::
emitAssociatedTypeMetadataRecord(const ProtocolConformance *Conformance) {
if (!IRGen.Opts.EnableReflectionMetadata)
return;
SmallVector<std::pair<StringRef, CanType>, 2> AssociatedTypes;
auto collectTypeWitness = [&](const AssociatedTypeDecl *AssocTy,
Type Replacement,
const TypeDecl *TD) -> bool {
AssociatedTypes.push_back({
AssocTy->getNameStr(),
Replacement->getCanonicalType()
});
return false;
};
Conformance->forEachTypeWitness(/*resolver*/ nullptr, collectTypeWitness);
// If there are no associated types, don't bother emitting any
// metadata.
if (AssociatedTypes.empty())
return;
AssociatedTypeMetadataBuilder builder(*this, Conformance, AssociatedTypes);
builder.emit();
}
void IRGenModule::emitBuiltinReflectionMetadata() {
if (getSwiftModule()->isStdlibModule()) {
BuiltinTypes.insert(Context.TheNativeObjectType);
BuiltinTypes.insert(Context.TheUnknownObjectType);
BuiltinTypes.insert(Context.TheBridgeObjectType);
BuiltinTypes.insert(Context.TheRawPointerType);
BuiltinTypes.insert(Context.TheUnsafeValueBufferType);
// This would not be necessary if RawPointer had the same set of
// extra inhabitants as these. But maybe it's best not to codify
// that in the ABI anyway.
CanType thinFunction = CanFunctionType::get(
{}, Context.TheEmptyTupleType,
AnyFunctionType::ExtInfo().withRepresentation(
FunctionTypeRepresentation::Thin));
BuiltinTypes.insert(thinFunction);
CanType anyMetatype = CanExistentialMetatypeType::get(
Context.TheAnyType);
BuiltinTypes.insert(anyMetatype);
}
for (auto CD : ImportedClasses)
emitFieldMetadataRecord(CD);
for (auto PD : ImportedProtocols)
emitFieldMetadataRecord(PD);
for (auto SD : ImportedStructs)
emitFieldMetadataRecord(SD);
for (auto builtinType : BuiltinTypes)
emitBuiltinTypeMetadataRecord(builtinType);
for (auto nominalDecl : OpaqueTypes)
emitOpaqueTypeMetadataRecord(nominalDecl);
}
void IRGenerator::emitBuiltinReflectionMetadata() {
for (auto &m : *this) {
m.second->emitBuiltinReflectionMetadata();
}
}
void IRGenModule::emitFieldMetadataRecord(const NominalTypeDecl *Decl) {
if (!IRGen.Opts.EnableReflectionMetadata)
return;
// @objc enums never have generic parameters or payloads,
// and lower as their raw type.
if (auto *ED = dyn_cast<EnumDecl>(Decl))
if (ED->isObjC()) {
emitOpaqueTypeMetadataRecord(ED);
return;
}
FieldTypeMetadataBuilder builder(*this, Decl);
FieldDescriptors.push_back(builder.emit());
}
void IRGenModule::emitReflectionMetadataVersion() {
auto Init =
llvm::ConstantInt::get(Int16Ty, SWIFT_REFLECTION_METADATA_VERSION);
auto Version = new llvm::GlobalVariable(Module, Int16Ty, /*constant*/ true,
llvm::GlobalValue::LinkOnceODRLinkage,
Init,
"__swift_reflection_version");
Version->setVisibility(llvm::GlobalValue::HiddenVisibility);
addUsedGlobal(Version);
}
void IRGenerator::emitReflectionMetadataVersion() {
for (auto &m : *this) {
m.second->emitReflectionMetadataVersion();
}
}