Skip to content

IRGen: Clean up FIXME in emitConditionalConformancesBuffer() #15200

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 1 commit into from
Mar 13, 2018
Merged

IRGen: Clean up FIXME in emitConditionalConformancesBuffer() #15200

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
112 changes: 49 additions & 63 deletions lib/IRGen/GenProto.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -982,7 +982,6 @@ class irgen::ConformanceInfo {
public:
virtual ~ConformanceInfo() {}
virtual llvm::Value *getTable(IRGenFunction &IGF,
CanType conformingType,
llvm::Value **conformingMetadataCache) const = 0;
/// Try to get this table as a constant pointer. This might just
/// not be supportable at all.
Expand All @@ -991,7 +990,7 @@ class irgen::ConformanceInfo {
};

static llvm::Value *
emitConditionalConformancesBuffer(IRGenFunction &IGF, CanType conformingType,
emitConditionalConformancesBuffer(IRGenFunction &IGF,
const ProtocolConformance *conformance) {
// Pointers to the witness tables, in the right order, which will be included
// in the buffer that gets passed to the witness table accessor.
Expand All @@ -1000,30 +999,6 @@ emitConditionalConformancesBuffer(IRGenFunction &IGF, CanType conformingType,
auto subMap = conformance->getSubstitutions(IGF.IGM.getSwiftModule());
auto rootConformance = conformance->getRootNormalConformance();

// Find the generic environment into which the witness table should be
// mapped.
// FIXME: Passing conformingType down for just this purpose feels like a
// hack.
if (conformingType->hasArchetype() &&
conformance->getType()->hasTypeParameter()) {
GenericEnvironment *conformingTypeEnv = nullptr;
conformingType.findIf([&](Type type) {
if (auto archetype = type->getAs<ArchetypeType>()) {
conformingTypeEnv = archetype->getGenericEnvironment();
return conformingTypeEnv != nullptr;
}

return false;
});

if (conformingTypeEnv) {
subMap = subMap.subst([&](SubstitutableType *dependentType) {
return conformingTypeEnv->mapTypeIntoContext(Type(dependentType));
},
LookUpConformanceInModule(IGF.getSwiftModule()));
}
}

SILWitnessTable::enumerateWitnessTableConditionalConformances(
rootConformance, [&](unsigned, CanType type, ProtocolDecl *proto) {
auto substType = type.subst(subMap)->getCanonicalType();
Expand Down Expand Up @@ -1056,7 +1031,7 @@ emitConditionalConformancesBuffer(IRGenFunction &IGF, CanType conformingType,

static llvm::Value *emitWitnessTableAccessorCall(
IRGenFunction &IGF, const ProtocolConformance *conformance,
CanType conformingType, llvm::Value **srcMetadataCache) {
llvm::Value **srcMetadataCache) {
auto accessor = IGF.IGM.getAddrOfWitnessTableAccessFunction(
conformance->getRootNormalConformance(), NotForDefinition);

Expand All @@ -1066,11 +1041,12 @@ static llvm::Value *emitWitnessTableAccessorCall(
if (conformance->witnessTableAccessorRequiresArguments()) {
// Emit the source metadata if we haven't yet.
if (!*srcMetadataCache) {
*srcMetadataCache = IGF.emitTypeMetadataRef(conformingType);
*srcMetadataCache = IGF.emitTypeMetadataRef(
conformance->getType()->getCanonicalType());
}

auto conditionalTables =
emitConditionalConformancesBuffer(IGF, conformingType, conformance);
emitConditionalConformancesBuffer(IGF, conformance);

call = IGF.Builder.CreateCall(accessor,
{*srcMetadataCache, conditionalTables});
Expand All @@ -1090,9 +1066,10 @@ static llvm::Value *emitWitnessTableAccessorCall(
/// given type.
static llvm::Function *
getWitnessTableLazyAccessFunction(IRGenModule &IGM,
const ProtocolConformance *conformance,
CanType conformingType) {
const ProtocolConformance *conformance) {
auto conformingType = conformance->getType()->getCanonicalType();
assert(!conformingType->hasArchetype());

auto rootConformance = conformance->getRootNormalConformance();
llvm::Function *accessor = IGM.getAddrOfWitnessTableLazyAccessFunction(
rootConformance, conformingType, ForDefinition);
Expand All @@ -1112,13 +1089,23 @@ getWitnessTableLazyAccessFunction(IRGenModule &IGM,
emitLazyCacheAccessFunction(IGM, accessor, cacheVariable,
[&](IRGenFunction &IGF) -> llvm::Value* {
llvm::Value *conformingMetadataCache = nullptr;
return emitWitnessTableAccessorCall(IGF, conformance, conformingType,
return emitWitnessTableAccessorCall(IGF, conformance,
&conformingMetadataCache);
});

return accessor;
}

static ProtocolConformance &mapConformanceIntoContext(IRGenModule &IGM,
const ProtocolConformance &conf,
DeclContext *dc) {
return *conf.subst(dc->mapTypeIntoContext(conf.getType()),
[&](SubstitutableType *t) -> Type {
return dc->mapTypeIntoContext(t);
},
LookUpConformanceInModule(IGM.getSwiftModule()));
}

namespace {

/// Conformance info for a witness table that can be directly generated.
Expand All @@ -1130,7 +1117,7 @@ class DirectConformanceInfo : public ConformanceInfo {
DirectConformanceInfo(const ProtocolConformance *C)
: RootConformance(C->getRootNormalConformance()) {}

llvm::Value *getTable(IRGenFunction &IGF, CanType conformingType,
llvm::Value *getTable(IRGenFunction &IGF,
llvm::Value **conformingMetadataCache) const override {
return IGF.IGM.getAddrOfWitnessTable(RootConformance);
}
Expand All @@ -1150,17 +1137,17 @@ class AccessorConformanceInfo : public ConformanceInfo {
public:
AccessorConformanceInfo(const ProtocolConformance *C) : Conformance(C) {}

llvm::Value *getTable(IRGenFunction &IGF, CanType type,
llvm::Value *getTable(IRGenFunction &IGF,
llvm::Value **typeMetadataCache) const override {
// If we're looking up a dependent type, we can't cache the result.
if (type->hasArchetype()) {
return emitWitnessTableAccessorCall(IGF, Conformance, type,
if (Conformance->getType()->hasArchetype()) {
return emitWitnessTableAccessorCall(IGF, Conformance,
typeMetadataCache);
}

// Otherwise, call a lazy-cache function.
auto accessor =
getWitnessTableLazyAccessFunction(IGF.IGM, Conformance, type);
getWitnessTableLazyAccessFunction(IGF.IGM, Conformance);
llvm::CallInst *call = IGF.Builder.CreateCall(accessor, {});
call->setCallingConv(IGF.IGM.DefaultCC);
call->setDoesNotAccessMemory();
Expand All @@ -1182,6 +1169,7 @@ class AccessorConformanceInfo : public ConformanceInfo {
unsigned TableSize = ~0U; // will get overwritten unconditionally
CanType ConcreteType;
const NormalProtocolConformance &Conformance;
const ProtocolConformance &ConformanceInContext;
ArrayRef<SILWitnessTable::Entry> SILEntries;
ArrayRef<SILWitnessTable::ConditionalConformance>
SILConditionalConformances;
Expand All @@ -1207,6 +1195,9 @@ class AccessorConformanceInfo : public ConformanceInfo {
->getCanonicalType())
->getCanonicalType()),
Conformance(*SILWT->getConformance()),
ConformanceInContext(mapConformanceIntoContext(IGM,
Conformance,
Conformance.getDeclContext())),
SILEntries(SILWT->getEntries()),
SILConditionalConformances(SILWT->getConditionalConformances()),
PI(IGM.getProtocolInfo(SILWT->getConformance()->getProtocol())) {
Expand Down Expand Up @@ -1254,8 +1245,9 @@ class AccessorConformanceInfo : public ConformanceInfo {

// Look for a protocol type info.
const ProtocolInfo &basePI = IGM.getProtocolInfo(baseProto);
const ProtocolConformance *astConf
= Conformance.getInheritedConformance(baseProto);
auto *astConf = ConformanceInContext.getInheritedConformance(baseProto);
assert(astConf->getType()->isEqual(ConcreteType));

const ConformanceInfo &conf =
basePI.getConformance(IGM, baseProto, astConf);

Expand Down Expand Up @@ -1328,15 +1320,9 @@ class AccessorConformanceInfo : public ConformanceInfo {

SILEntries = SILEntries.slice(1);

auto interfaceAssociate =
Conformance.getTypeWitness(requirement.getAssociation(), nullptr);

// This type will be expressed in terms of the archetypes
// of the conforming context.
assert(!interfaceAssociate->hasArchetype());
auto associate = Conformance.getDeclContext()->mapTypeIntoContext(interfaceAssociate)
->getCanonicalType();

auto associate =
ConformanceInContext.getTypeWitness(
requirement.getAssociation(), nullptr)->getCanonicalType();

llvm::Constant *metadataAccessFunction =
getAssociatedTypeMetadataAccessFunction(requirement, associate);
Expand All @@ -1346,17 +1332,14 @@ class AccessorConformanceInfo : public ConformanceInfo {
void addAssociatedConformance(AssociatedConformance requirement) {
// FIXME: Add static witness tables for type conformances.

auto interfaceAssociate =
Conformance.getAssociatedType(requirement.getAssociation());
assert(!interfaceAssociate->hasArchetype());

auto associate =
Conformance.getDeclContext()->mapTypeIntoContext(interfaceAssociate)
->getCanonicalType();
ConformanceInContext.getAssociatedType(
requirement.getAssociation())->getCanonicalType();

ProtocolConformanceRef associatedConformance =
Conformance.getAssociatedConformance(requirement.getAssociation(),
requirement.getAssociatedRequirement());
ConformanceInContext.getAssociatedConformance(
requirement.getAssociation(),
requirement.getAssociatedRequirement());

#ifndef NDEBUG
auto &entry = SILEntries.front();
Expand Down Expand Up @@ -1544,9 +1527,10 @@ getAssociatedTypeMetadataAccessFunction(AssociatedType requirement,
/// the conformance is being requested; it may ignore this (perhaps
/// implicitly by taking no arguments).
static llvm::Constant *
getOrCreateWitnessTableAccessFunction(IRGenModule &IGM, CanType type,
getOrCreateWitnessTableAccessFunction(IRGenModule &IGM,
ProtocolConformance *conformance) {
assert(!type->hasArchetype() && "cannot do this for dependent type");
assert(!conformance->getType()->hasArchetype() &&
"cannot do this for dependent type");

// We always emit an access function for conformances, and in principle
// it is always possible to just use that here directly. However,
Expand All @@ -1558,7 +1542,7 @@ getOrCreateWitnessTableAccessFunction(IRGenModule &IGM, CanType type,
// function.
auto rootConformance = conformance->getRootNormalConformance();
if (rootConformance->witnessTableAccessorRequiresArguments()) {
return getWitnessTableLazyAccessFunction(IGM, conformance, type);
return getWitnessTableLazyAccessFunction(IGM, conformance);
} else {
return IGM.getAddrOfWitnessTableAccessFunction(rootConformance,
NotForDefinition);
Expand All @@ -1583,7 +1567,7 @@ getAssociatedTypeWitnessTableAccessFunction(AssociatedConformance requirement,
if (!associatedType->hasArchetype()) {
assert(associatedConformance.isConcrete() &&
"no concrete conformance for non-dependent type");
return getOrCreateWitnessTableAccessFunction(IGM, associatedType,
return getOrCreateWitnessTableAccessFunction(IGM,
associatedConformance.getConcrete());
}

Expand Down Expand Up @@ -1630,6 +1614,8 @@ getAssociatedTypeWitnessTableAccessFunction(AssociatedConformance requirement,

const ConformanceInfo *conformanceI = nullptr;
if (associatedConformance.isConcrete()) {
assert(associatedType->isEqual(associatedConformance.getConcrete()->getType()));

const ProtocolInfo &protocolI = IGM.getProtocolInfo(associatedProtocol);
conformanceI =
&protocolI.getConformance(IGM, associatedProtocol,
Expand Down Expand Up @@ -1681,7 +1667,7 @@ getAssociatedTypeWitnessTableAccessFunction(AssociatedConformance requirement,
// Otherwise, we need a cache entry.
emitReturnOfCheckedLoadFromCache(IGF, destTable, self,
[&]() -> llvm::Value* {
return conformanceI->getTable(IGF, associatedType, &associatedTypeMetadata);
return conformanceI->getTable(IGF, &associatedTypeMetadata);
});

return accessor;
Expand Down Expand Up @@ -1896,7 +1882,7 @@ llvm::Constant *WitnessTableBuilder::buildInstantiationFunction() {
for (auto &base : SpecializedBaseConformances) {
// Ask the ConformanceInfo to emit the wtable.
llvm::Value *baseWTable =
base.second->getTable(IGF, ConcreteType, &metadata);
base.second->getTable(IGF, &metadata);
baseWTable = IGF.Builder.CreateBitCast(baseWTable, IGM.Int8PtrTy);

// Store that to the appropriate slot in the new witness table.
Expand Down Expand Up @@ -2590,7 +2576,7 @@ llvm::Value *irgen::emitWitnessTableRef(IRGenFunction &IGF,
auto &protoI = IGF.IGM.getProtocolInfo(proto);
auto &conformanceI =
protoI.getConformance(IGF.IGM, proto, concreteConformance);
wtable = conformanceI.getTable(IGF, srcType, srcMetadataCache);
wtable = conformanceI.getTable(IGF, srcMetadataCache);

IGF.setScopedLocalTypeData(
srcType,
Expand Down