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GenHeap.cpp
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//===--- GenHeap.cpp - Layout of heap objects and their metadata ----------===//
//
// This source file is part of the Swift.org open source project
//
// Copyright (c) 2014 - 2015 Apple Inc. and the Swift project authors
// Licensed under Apache License v2.0 with Runtime Library Exception
//
// See http://swift.org/LICENSE.txt for license information
// See http://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
//
//===----------------------------------------------------------------------===//
//
// This file implements routines for arbitrary Swift-native heap objects,
// such as layout and reference-counting.
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/ErrorHandling.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Intrinsics.h"
#include "swift/Basic/Fallthrough.h"
#include "swift/Basic/SourceLoc.h"
#include "swift/ABI/MetadataValues.h"
#include "Explosion.h"
#include "GenProto.h"
#include "GenType.h"
#include "IRGenDebugInfo.h"
#include "IRGenFunction.h"
#include "IRGenModule.h"
#include "HeapTypeInfo.h"
#include "IndirectTypeInfo.h"
#include "UnownedTypeInfo.h"
#include "WeakTypeInfo.h"
#include "GenHeap.h"
using namespace swift;
using namespace irgen;
/// Produce a constant to place in a metatype's isa field
/// corresponding to the given metadata kind.
static llvm::ConstantInt *getMetadataKind(IRGenModule &IGM,
MetadataKind kind) {
return llvm::ConstantInt::get(IGM.MetadataKindTy, uint8_t(kind));
}
/// Perform the layout required for a heap object.
HeapLayout::HeapLayout(IRGenModule &IGM, LayoutStrategy strategy,
ArrayRef<SILType> fieldTypes,
ArrayRef<const TypeInfo *> fieldTypeInfos,
llvm::StructType *typeToFill,
NecessaryBindings &&bindings)
: StructLayout(IGM, CanType(), LayoutKind::HeapObject, strategy,
fieldTypeInfos, typeToFill),
ElementTypes(fieldTypes.begin(), fieldTypes.end()),
Bindings(std::move(bindings))
{
#ifndef NDEBUG
assert(fieldTypeInfos.size() == fieldTypes.size()
&& "type infos don't match types");
if (!Bindings.empty()) {
assert(fieldTypeInfos.size() >= 1 && "no field for bindings");
auto fixedBindingsField = dyn_cast<FixedTypeInfo>(fieldTypeInfos[0]);
assert(fixedBindingsField
&& "bindings field is not fixed size");
assert(fixedBindingsField->getFixedSize()
== Bindings.getBufferSize(IGM)
&& fixedBindingsField->getFixedAlignment()
== IGM.getPointerAlignment()
&& "bindings field doesn't fit bindings");
}
#endif
}
HeapNonFixedOffsets::HeapNonFixedOffsets(IRGenFunction &IGF,
const HeapLayout &layout) {
if (!layout.isFixedLayout()) {
// Calculate all the non-fixed layouts.
// TODO: We could be lazier about this.
llvm::Value *offset = nullptr;
llvm::Value *totalAlign = llvm::ConstantInt::get(IGF.IGM.SizeTy,
layout.getAlignment().getMaskValue());
for (unsigned i : indices(layout.getElements())) {
auto &elt = layout.getElement(i);
auto eltTy = layout.getElementTypes()[i];
switch (elt.getKind()) {
case ElementLayout::Kind::InitialNonFixedSize:
// Factor the non-fixed-size field's alignment into the total alignment.
totalAlign = IGF.Builder.CreateOr(totalAlign,
elt.getType().getAlignmentMask(IGF, eltTy));
SWIFT_FALLTHROUGH;
case ElementLayout::Kind::Empty:
case ElementLayout::Kind::Fixed:
// Don't need to dynamically calculate this offset.
Offsets.push_back(nullptr);
break;
case ElementLayout::Kind::NonFixed:
// Start calculating non-fixed offsets from the end of the first fixed
// field.
assert(i > 0 && "shouldn't begin with a non-fixed field");
auto &prevElt = layout.getElement(i-1);
auto prevType = layout.getElementTypes()[i-1];
// Start calculating offsets from the last fixed-offset field.
if (!offset) {
Size lastFixedOffset = layout.getElement(i-1).getByteOffset();
if (auto *fixedType = dyn_cast<FixedTypeInfo>(&prevElt.getType())) {
// If the last fixed-offset field is also fixed-size, we can
// statically compute the end of the fixed-offset fields.
auto fixedEnd = lastFixedOffset + fixedType->getFixedSize();
offset
= llvm::ConstantInt::get(IGF.IGM.SizeTy, fixedEnd.getValue());
} else {
// Otherwise, we need to add the dynamic size to the fixed start
// offset.
offset
= llvm::ConstantInt::get(IGF.IGM.SizeTy,
lastFixedOffset.getValue());
offset = IGF.Builder.CreateAdd(offset,
prevElt.getType().getSize(IGF, prevType));
}
}
// Round up to alignment to get the offset.
auto alignMask = elt.getType().getAlignmentMask(IGF, eltTy);
auto notAlignMask = IGF.Builder.CreateNot(alignMask);
offset = IGF.Builder.CreateAdd(offset, alignMask);
offset = IGF.Builder.CreateAnd(offset, notAlignMask);
Offsets.push_back(offset);
// Advance by the field's size to start the next field.
offset = IGF.Builder.CreateAdd(offset,
elt.getType().getSize(IGF, eltTy));
totalAlign = IGF.Builder.CreateOr(totalAlign, alignMask);
break;
}
}
TotalSize = offset;
TotalAlignMask = totalAlign;
} else {
TotalSize = layout.emitSize(IGF.IGM);
TotalAlignMask = layout.emitAlignMask(IGF.IGM);
}
}
void irgen::emitDeallocateHeapObject(IRGenFunction &IGF,
llvm::Value *object,
llvm::Value *size,
llvm::Value *alignMask) {
// FIXME: We should call a fast deallocator for heap objects with
// known size.
IGF.Builder.CreateCall(IGF.IGM.getDeallocObjectFn(),
{object, size, alignMask});
}
void irgen::emitDeallocateClassInstance(IRGenFunction &IGF,
llvm::Value *object,
llvm::Value *size,
llvm::Value *alignMask,
ClassDeallocationKind kind) {
// FIXME: We should call a fast deallocator for heap objects with
// known size.
llvm::Constant *fn;
switch(kind) {
case ClassDeallocationKind::DestructorPlusZero:
fn = IGF.IGM.getDeallocClassInstanceFn();
break;
case ClassDeallocationKind::ConstructorPlusOne:
fn = IGF.IGM.getDeallocUninitializedClassInstanceFn();
break;
}
IGF.Builder.CreateCall(fn, {object, size, alignMask});
}
void irgen::emitDeallocatePartialClassInstance(IRGenFunction &IGF,
llvm::Value *object,
llvm::Value *metadata,
llvm::Value *size,
llvm::Value *alignMask) {
// FIXME: We should call a fast deallocator for heap objects with
// known size.
IGF.Builder.CreateCall(IGF.IGM.getDeallocPartialClassInstanceFn(),
{object, metadata, size, alignMask});
}
/// Create the destructor function for a layout.
/// TODO: give this some reasonable name and possibly linkage.
static llvm::Function *createDtorFn(IRGenModule &IGM,
const HeapLayout &layout) {
llvm::Function *fn =
llvm::Function::Create(IGM.DeallocatingDtorTy,
llvm::Function::PrivateLinkage,
"objectdestroy", &IGM.Module);
fn->setAttributes(IGM.constructInitialAttributes());
IRGenFunction IGF(IGM, fn);
if (IGM.DebugInfo)
IGM.DebugInfo->emitArtificialFunction(IGF, fn);
Address structAddr = layout.emitCastTo(IGF, fn->arg_begin());
// Bind necessary bindings, if we have them.
if (layout.hasBindings()) {
// The type metadata bindings should be at a fixed offset, so we can pass
// None for NonFixedOffsets. If we didn't, we'd have a chicken-egg problem.
auto bindingsAddr = layout.getElement(0).project(IGF, structAddr, None);
layout.getBindings().restore(IGF, bindingsAddr);
}
// Figure out the non-fixed offsets.
HeapNonFixedOffsets offsets(IGF, layout);
// Destroy the fields.
for (unsigned i : indices(layout.getElements())) {
auto &field = layout.getElement(i);
auto fieldTy = layout.getElementTypes()[i];
if (field.isPOD())
continue;
field.getType().destroy(IGF, field.project(IGF, structAddr, offsets),
fieldTy);
}
emitDeallocateHeapObject(IGF, fn->arg_begin(), offsets.getSize(),
offsets.getAlignMask());
IGF.Builder.CreateRetVoid();
return fn;
}
/// Create the size function for a layout.
/// TODO: give this some reasonable name and possibly linkage.
llvm::Constant *HeapLayout::createSizeFn(IRGenModule &IGM) const {
llvm::Function *fn =
llvm::Function::Create(IGM.DeallocatingDtorTy,
llvm::Function::PrivateLinkage,
"objectsize", &IGM.Module);
fn->setAttributes(IGM.constructInitialAttributes());
IRGenFunction IGF(IGM, fn);
if (IGM.DebugInfo)
IGM.DebugInfo->emitArtificialFunction(IGF, fn);
// Ignore the object pointer; we aren't a dynamically-sized array,
// so it's pointless.
llvm::Value *size = emitSize(IGM);
IGF.Builder.CreateRet(size);
return fn;
}
static llvm::Constant *buildPrivateMetadata(IRGenModule &IGM,
const HeapLayout &layout,
llvm::Constant *dtorFn,
MetadataKind kind) {
// Build the fields of the private metadata.
SmallVector<llvm::Constant*, 4> fields;
fields.push_back(dtorFn);
fields.push_back(llvm::ConstantPointerNull::get(IGM.WitnessTablePtrTy));
fields.push_back(llvm::ConstantStruct::get(IGM.TypeMetadataStructTy,
getMetadataKind(IGM, kind)));
// Figure out the offset to the first element, which is necessary to be able
// to polymorphically project as a generic box.
auto elements = layout.getElements();
Size offset;
if (!elements.empty()
&& elements[0].getKind() == ElementLayout::Kind::Fixed)
offset = elements[0].getByteOffset();
else
offset = Size(0);
fields.push_back(llvm::ConstantInt::get(IGM.Int32Ty, offset.getValue()));
llvm::Constant *init =
llvm::ConstantStruct::get(IGM.FullBoxMetadataStructTy, fields);
llvm::GlobalVariable *var =
new llvm::GlobalVariable(IGM.Module, IGM.FullBoxMetadataStructTy,
/*constant*/ true,
llvm::GlobalVariable::PrivateLinkage, init,
"metadata");
llvm::Constant *indices[] = {
llvm::ConstantInt::get(IGM.Int32Ty, 0),
llvm::ConstantInt::get(IGM.Int32Ty, 2)
};
return llvm::ConstantExpr::getInBoundsGetElementPtr(
/*Ty=*/nullptr, var, indices);
}
llvm::Constant *HeapLayout::getPrivateMetadata(IRGenModule &IGM) const {
if (!privateMetadata)
privateMetadata = buildPrivateMetadata(IGM, *this, createDtorFn(IGM, *this),
MetadataKind::HeapLocalVariable);
return privateMetadata;
}
llvm::Value *IRGenFunction::emitUnmanagedAlloc(const HeapLayout &layout,
const llvm::Twine &name,
const HeapNonFixedOffsets *offsets) {
llvm::Value *metadata = layout.getPrivateMetadata(IGM);
llvm::Value *size, *alignMask;
if (offsets) {
size = offsets->getSize();
alignMask = offsets->getAlignMask();
} else {
size = layout.emitSize(IGM);
alignMask = layout.emitAlignMask(IGM);
}
return emitAllocObjectCall(metadata, size, alignMask, name);
}
namespace {
class BuiltinNativeObjectTypeInfo
: public HeapTypeInfo<BuiltinNativeObjectTypeInfo> {
public:
BuiltinNativeObjectTypeInfo(llvm::PointerType *storage,
Size size, SpareBitVector spareBits,
Alignment align)
: HeapTypeInfo(storage, size, spareBits, align) {}
/// Builtin.NativeObject uses Swift native reference-counting.
ReferenceCounting getReferenceCounting() const {
return ReferenceCounting::Native;
}
};
}
const LoadableTypeInfo *TypeConverter::convertBuiltinNativeObject() {
return new BuiltinNativeObjectTypeInfo(IGM.RefCountedPtrTy,
IGM.getPointerSize(),
IGM.getHeapObjectSpareBits(),
IGM.getPointerAlignment());
}
namespace {
/// A type implementation for an @unowned(unsafe) reference to an
/// object.
class UnmanagedReferenceTypeInfo
: public PODSingleScalarTypeInfo<UnmanagedReferenceTypeInfo,
LoadableTypeInfo> {
public:
UnmanagedReferenceTypeInfo(llvm::Type *type,
const SpareBitVector &spareBits,
Size size, Alignment alignment)
: PODSingleScalarTypeInfo(type, size, spareBits, alignment) {}
// Unmanaged types have the same spare bits as managed heap objects.
bool mayHaveExtraInhabitants(IRGenModule &IGM) const override {
return true;
}
unsigned getFixedExtraInhabitantCount(IRGenModule &IGM) const override {
return getHeapObjectExtraInhabitantCount(IGM);
}
APInt getFixedExtraInhabitantValue(IRGenModule &IGM,
unsigned bits,
unsigned index) const override {
return getHeapObjectFixedExtraInhabitantValue(IGM, bits, index, 0);
}
llvm::Value *getExtraInhabitantIndex(IRGenFunction &IGF, Address src,
SILType T)
const override {
return getHeapObjectExtraInhabitantIndex(IGF, src);
}
void storeExtraInhabitant(IRGenFunction &IGF, llvm::Value *index,
Address dest, SILType T) const override {
return storeHeapObjectExtraInhabitant(IGF, index, dest);
}
};
}
const LoadableTypeInfo *
TypeConverter::createUnmanagedStorageType(llvm::Type *valueType) {
return new UnmanagedReferenceTypeInfo(valueType,
IGM.getHeapObjectSpareBits(),
IGM.getPointerSize(),
IGM.getPointerAlignment());
}
namespace {
/// A type implementation for an [unowned] reference to an object
/// with a known-Swift reference count.
class SwiftUnownedReferenceTypeInfo
: public SingleScalarTypeInfo<SwiftUnownedReferenceTypeInfo,
UnownedTypeInfo> {
public:
SwiftUnownedReferenceTypeInfo(llvm::Type *type,
const SpareBitVector &spareBits,
Size size, Alignment alignment)
: SingleScalarTypeInfo(type, size, spareBits, alignment) {}
enum { IsScalarPOD = false };
void emitScalarRetain(IRGenFunction &IGF, llvm::Value *value) const {
IGF.emitUnownedRetain(value);
}
void emitScalarRelease(IRGenFunction &IGF, llvm::Value *value) const {
IGF.emitUnownedRelease(value);
}
void emitScalarFixLifetime(IRGenFunction &IGF, llvm::Value *value) const {
IGF.emitFixLifetime(value);
}
// Unowned types have the same spare bits as strong heap object refs.
bool mayHaveExtraInhabitants(IRGenModule &IGM) const override {
return true;
}
unsigned getFixedExtraInhabitantCount(IRGenModule &IGM) const override {
return getHeapObjectExtraInhabitantCount(IGM);
}
APInt getFixedExtraInhabitantValue(IRGenModule &IGM,
unsigned bits,
unsigned index) const override {
return getHeapObjectFixedExtraInhabitantValue(IGM, bits, index, 0);
}
llvm::Value *getExtraInhabitantIndex(IRGenFunction &IGF, Address src,
SILType T)
const override {
return getHeapObjectExtraInhabitantIndex(IGF, src);
}
void storeExtraInhabitant(IRGenFunction &IGF, llvm::Value *index,
Address dest, SILType T) const override {
return storeHeapObjectExtraInhabitant(IGF, index, dest);
}
};
/// A type implementation for a [weak] reference to an object
/// with a known-Swift reference count.
class SwiftWeakReferenceTypeInfo
: public IndirectTypeInfo<SwiftWeakReferenceTypeInfo,
WeakTypeInfo> {
llvm::Type *ValueType;
public:
SwiftWeakReferenceTypeInfo(llvm::Type *valueType,
llvm::Type *weakType,
Size size, Alignment alignment,
SpareBitVector &&spareBits)
: IndirectTypeInfo(weakType, size, alignment, std::move(spareBits)),
ValueType(valueType) {}
void initializeWithCopy(IRGenFunction &IGF, Address destAddr,
Address srcAddr, SILType T) const override {
IGF.emitWeakCopyInit(destAddr, srcAddr);
}
void initializeWithTake(IRGenFunction &IGF, Address destAddr,
Address srcAddr, SILType T) const override {
IGF.emitWeakTakeInit(destAddr, srcAddr);
}
void assignWithCopy(IRGenFunction &IGF, Address destAddr,
Address srcAddr, SILType T) const override {
IGF.emitWeakCopyAssign(destAddr, srcAddr);
}
void assignWithTake(IRGenFunction &IGF, Address destAddr,
Address srcAddr, SILType T) const override {
IGF.emitWeakTakeAssign(destAddr, srcAddr);
}
void destroy(IRGenFunction &IGF, Address addr, SILType T) const override {
IGF.emitWeakDestroy(addr);
}
llvm::Type *getOptionalIntType() const {
return llvm::IntegerType::get(ValueType->getContext(),
getFixedSize().getValueInBits());
}
void weakLoadStrong(IRGenFunction &IGF, Address addr,
Explosion &out) const override {
auto value = IGF.emitWeakLoadStrong(addr, ValueType);
// The optional will be lowered to an integer type the size of the word.
out.add(IGF.Builder.CreatePtrToInt(value, getOptionalIntType()));
}
void weakTakeStrong(IRGenFunction &IGF, Address addr,
Explosion &out) const override {
auto value = IGF.emitWeakTakeStrong(addr, ValueType);
// The optional will be lowered to an integer type the size of the word.
out.add(IGF.Builder.CreatePtrToInt(value, getOptionalIntType()));
}
void weakInit(IRGenFunction &IGF, Explosion &in,
Address dest) const override {
llvm::Value *value = in.claimNext();
// The optional will be lowered to an integer type the size of the word.
assert(value->getType() == getOptionalIntType());
value = IGF.Builder.CreateIntToPtr(value, ValueType);
IGF.emitWeakInit(value, dest);
}
void weakAssign(IRGenFunction &IGF, Explosion &in,
Address dest) const override {
llvm::Value *value = in.claimNext();
// The optional will be lowered to an integer type the size of the word.
assert(value->getType() == getOptionalIntType());
value = IGF.Builder.CreateIntToPtr(value, ValueType);
IGF.emitWeakAssign(value, dest);
}
};
}
const UnownedTypeInfo *
TypeConverter::createSwiftUnownedStorageType(llvm::Type *valueType) {
return new SwiftUnownedReferenceTypeInfo(valueType,
IGM.getHeapObjectSpareBits(),
IGM.getPointerSize(),
IGM.getPointerAlignment());
}
const WeakTypeInfo *
TypeConverter::createSwiftWeakStorageType(llvm::Type *valueType) {
return new SwiftWeakReferenceTypeInfo(valueType,
IGM.WeakReferencePtrTy->getElementType(),
IGM.getWeakReferenceSize(),
IGM.getWeakReferenceAlignment(),
IGM.getWeakReferenceSpareBits());
}
SpareBitVector IRGenModule::getWeakReferenceSpareBits() const {
// The runtime needs to be able to freely manipulate live weak
// references without worrying about us mucking around with their
// bits, so weak references are completely opaque.
return SpareBitVector::getConstant(getWeakReferenceSize().getValueInBits(),
false);
}
namespace {
/// A type implementation for an [unowned] reference to an object
/// that is not necessarily a Swift object.
class UnknownUnownedReferenceTypeInfo :
public SingleScalarTypeInfo<UnknownUnownedReferenceTypeInfo,
UnownedTypeInfo> {
public:
UnknownUnownedReferenceTypeInfo(llvm::Type *type,
const SpareBitVector &spareBits,
Size size, Alignment alignment)
: SingleScalarTypeInfo(type, size, spareBits, alignment) {}
enum { IsScalarPOD = false };
void emitScalarRetain(IRGenFunction &IGF, llvm::Value *value) const {
IGF.emitUnknownUnownedRetain(value);
}
void emitScalarRelease(IRGenFunction &IGF, llvm::Value *value) const {
IGF.emitUnknownUnownedRelease(value);
}
void emitScalarFixLifetime(IRGenFunction &IGF, llvm::Value *value) const {
IGF.emitFixLifetime(value);
}
// Unowned types have the same spare bits as strong unknown object refs.
bool mayHaveExtraInhabitants(IRGenModule &IGM) const override {
return true;
}
unsigned getFixedExtraInhabitantCount(IRGenModule &IGM) const override {
return getHeapObjectExtraInhabitantCount(IGM);
}
APInt getFixedExtraInhabitantValue(IRGenModule &IGM,
unsigned bits,
unsigned index) const override {
return getHeapObjectFixedExtraInhabitantValue(IGM, bits, index, 0);
}
llvm::Value *getExtraInhabitantIndex(IRGenFunction &IGF, Address src,
SILType T)
const override {
return getHeapObjectExtraInhabitantIndex(IGF, src);
}
void storeExtraInhabitant(IRGenFunction &IGF, llvm::Value *index,
Address dest, SILType T) const override {
return storeHeapObjectExtraInhabitant(IGF, index, dest);
}
};
/// A type implementation for a [weak] reference to an object
/// that is not necessarily a Swift object.
class UnknownWeakReferenceTypeInfo :
public IndirectTypeInfo<UnknownWeakReferenceTypeInfo,
WeakTypeInfo> {
/// We need to separately store the value type because we always
/// use the same type to store the weak reference struct.
llvm::Type *ValueType;
public:
UnknownWeakReferenceTypeInfo(llvm::Type *valueType,
llvm::Type *weakType,
Size size, Alignment alignment,
SpareBitVector &&spareBits)
: IndirectTypeInfo(weakType, size, alignment, std::move(spareBits)),
ValueType(valueType) {}
void initializeWithCopy(IRGenFunction &IGF, Address destAddr,
Address srcAddr, SILType T) const override {
IGF.emitUnknownWeakCopyInit(destAddr, srcAddr);
}
void initializeWithTake(IRGenFunction &IGF, Address destAddr,
Address srcAddr, SILType T) const override {
IGF.emitUnknownWeakTakeInit(destAddr, srcAddr);
}
void assignWithCopy(IRGenFunction &IGF, Address destAddr,
Address srcAddr, SILType T) const override {
IGF.emitUnknownWeakCopyAssign(destAddr, srcAddr);
}
void assignWithTake(IRGenFunction &IGF, Address destAddr,
Address srcAddr, SILType T) const override {
IGF.emitUnknownWeakTakeAssign(destAddr, srcAddr);
}
void destroy(IRGenFunction &IGF, Address addr, SILType T) const override {
IGF.emitUnknownWeakDestroy(addr);
}
llvm::Type *getOptionalIntType() const {
return llvm::IntegerType::get(ValueType->getContext(),
getFixedSize().getValueInBits());
}
void weakLoadStrong(IRGenFunction &IGF, Address addr,
Explosion &out) const override {
auto value = IGF.emitUnknownWeakLoadStrong(addr, ValueType);
// The optional will be lowered to an integer type the size of the word.
out.add(IGF.Builder.CreatePtrToInt(value, getOptionalIntType()));
}
void weakTakeStrong(IRGenFunction &IGF, Address addr,
Explosion &out) const override {
auto value = IGF.emitUnknownWeakTakeStrong(addr, ValueType);
// The optional will be lowered to an integer type the size of the word.
out.add(IGF.Builder.CreatePtrToInt(value, getOptionalIntType()));
}
void weakInit(IRGenFunction &IGF, Explosion &in,
Address dest) const override {
llvm::Value *value = in.claimNext();
// The optional will be lowered to an integer type the size of the word.
assert(value->getType() == getOptionalIntType());
value = IGF.Builder.CreateIntToPtr(value, ValueType);
IGF.emitUnknownWeakInit(value, dest);
}
void weakAssign(IRGenFunction &IGF, Explosion &in,
Address dest) const override {
llvm::Value *value = in.claimNext();
// The optional will be lowered to an integer type the size of the word.
assert(value->getType() == getOptionalIntType());
value = IGF.Builder.CreateIntToPtr(value, ValueType);
IGF.emitUnknownWeakAssign(value, dest);
}
};
}
const UnownedTypeInfo *
TypeConverter::createUnknownUnownedStorageType(llvm::Type *valueType) {
return new UnknownUnownedReferenceTypeInfo(valueType,
IGM.getHeapObjectSpareBits(),
IGM.getPointerSize(),
IGM.getPointerAlignment());
}
const WeakTypeInfo *
TypeConverter::createUnknownWeakStorageType(llvm::Type *valueType) {
return new UnknownWeakReferenceTypeInfo(valueType,
IGM.WeakReferencePtrTy->getElementType(),
IGM.getWeakReferenceSize(),
IGM.getWeakReferenceAlignment(),
IGM.getWeakReferenceSpareBits());
}
/// Does the given value superficially not require reference-counting?
static bool doesNotRequireRefCounting(llvm::Value *value) {
// Constants never require reference-counting.
return isa<llvm::Constant>(value);
}
static llvm::FunctionType *getTypeOfFunction(llvm::Constant *fn) {
return cast<llvm::FunctionType>(fn->getType()->getPointerElementType());
}
/// Emit a unary call to perform a ref-counting operation.
///
/// \param fn - expected signature 'void (T)'
static void emitUnaryRefCountCall(IRGenFunction &IGF,
llvm::Constant *fn,
llvm::Value *value) {
// Instead of casting the input, we cast the function type.
// This tends to produce less IR, but might be evil.
if (value->getType() != getTypeOfFunction(fn)->getParamType(0)) {
llvm::FunctionType *fnType =
llvm::FunctionType::get(IGF.IGM.VoidTy, value->getType(), false);
fn = llvm::ConstantExpr::getBitCast(fn, fnType->getPointerTo());
}
// Emit the call.
llvm::CallInst *call = IGF.Builder.CreateCall(fn, value);
call->setCallingConv(IGF.IGM.RuntimeCC);
call->setDoesNotThrow();
}
/// Emit a copy-like call to perform a ref-counting operation.
///
/// \param fn - expected signature 'void (T, T)'
static void emitCopyLikeCall(IRGenFunction &IGF,
llvm::Constant *fn,
llvm::Value *dest,
llvm::Value *src) {
assert(dest->getType() == src->getType() &&
"type mismatch in binary refcounting operation");
// Instead of casting the inputs, we cast the function type.
// This tends to produce less IR, but might be evil.
if (dest->getType() != getTypeOfFunction(fn)->getParamType(0)) {
llvm::Type *paramTypes[] = { dest->getType(), dest->getType() };
llvm::FunctionType *fnType =
llvm::FunctionType::get(IGF.IGM.VoidTy, paramTypes, false);
fn = llvm::ConstantExpr::getBitCast(fn, fnType->getPointerTo());
}
// Emit the call.
llvm::CallInst *call = IGF.Builder.CreateCall(fn, {dest, src});
call->setCallingConv(IGF.IGM.RuntimeCC);
call->setDoesNotThrow();
}
/// Emit a call to a function with a loadWeak-like signature.
///
/// \param fn - expected signature 'T (Weak*)'
static llvm::Value *emitLoadWeakLikeCall(IRGenFunction &IGF,
llvm::Constant *fn,
llvm::Value *addr,
llvm::Type *resultType) {
assert(addr->getType() == IGF.IGM.WeakReferencePtrTy &&
"address is not of a weak reference");
// Instead of casting the output, we cast the function type.
// This tends to produce less IR, but might be evil.
if (resultType != getTypeOfFunction(fn)->getReturnType()) {
llvm::Type *paramTypes[] = { addr->getType() };
llvm::FunctionType *fnType =
llvm::FunctionType::get(resultType, paramTypes, false);
fn = llvm::ConstantExpr::getBitCast(fn, fnType->getPointerTo());
}
// Emit the call.
llvm::CallInst *call = IGF.Builder.CreateCall(fn, addr);
call->setCallingConv(IGF.IGM.RuntimeCC);
call->setDoesNotThrow();
return call;
}
/// Emit a call to a function with a storeWeak-like signature.
///
/// \param fn - expected signature 'void (Weak*, T)'
static void emitStoreWeakLikeCall(IRGenFunction &IGF,
llvm::Constant *fn,
llvm::Value *addr,
llvm::Value *value) {
assert(addr->getType() == IGF.IGM.WeakReferencePtrTy &&
"address is not of a weak reference");
// Instead of casting the inputs, we cast the function type.
// This tends to produce less IR, but might be evil.
if (value->getType() != getTypeOfFunction(fn)->getParamType(1)) {
llvm::Type *paramTypes[] = { addr->getType(), value->getType() };
llvm::FunctionType *fnType =
llvm::FunctionType::get(IGF.IGM.VoidTy, paramTypes, false);
fn = llvm::ConstantExpr::getBitCast(fn, fnType->getPointerTo());
}
// Emit the call.
llvm::CallInst *call = IGF.Builder.CreateCall(fn, {addr, value});
call->setCallingConv(IGF.IGM.RuntimeCC);
call->setDoesNotThrow();
}
/// Emit a call to swift_retain. In general, you should not be using
/// this routine; instead you should use emitRetain, which properly
/// balances the retain.
void IRGenFunction::emitRetainCall(llvm::Value *value) {
// Make sure the input pointer is the right type.
if (value->getType() != IGM.RefCountedPtrTy)
value = Builder.CreateBitCast(value, IGM.RefCountedPtrTy);
// Emit the call.
llvm::CallInst *call = Builder.CreateCall(IGM.getRetainFn(), value);
call->setCallingConv(IGM.RuntimeCC);
call->setDoesNotThrow();
}
/// Emit a retain of a value. This is usually not required because
/// values in explosions are typically "live", i.e. have a +1 owned by
/// the explosion.
void IRGenFunction::emitRetain(llvm::Value *value, Explosion &out) {
if (doesNotRequireRefCounting(value)) {
out.add(value);
return;
}
emitRetainCall(value);
out.add(value);
}
/// Emit a load of a live value from the given retaining variable.
void IRGenFunction::emitLoadAndRetain(Address address, Explosion &out) {
llvm::Value *value = Builder.CreateLoad(address);
emitRetainCall(value);
out.add(value);
}
/// Emit a store of a live value to the given retaining variable.
void IRGenFunction::emitAssignRetained(llvm::Value *newValue, Address address) {
// Pull the old value out of the address.
llvm::Value *oldValue = Builder.CreateLoad(address);
// We assume the new value is already retained.
Builder.CreateStore(newValue, address);
// Release the old value.
emitRelease(oldValue);
}
/// Emit an initialize of a live value to the given retaining variable.
void IRGenFunction::emitInitializeRetained(llvm::Value *newValue,
Address address) {
// We assume the new value is already retained.
Builder.CreateStore(newValue, address);
}
/// Emit a release of a live value with the given refcounting implementation.
void IRGenFunction::emitScalarRelease(llvm::Value *value,
ReferenceCounting refcounting) {
switch (refcounting) {
case ReferenceCounting::Native:
return emitRelease(value);
case ReferenceCounting::ObjC:
return emitObjCRelease(value);
case ReferenceCounting::Block:
return emitBlockRelease(value);
case ReferenceCounting::Unknown:
return emitUnknownRelease(value);
case ReferenceCounting::Bridge:
return emitBridgeRelease(value);
case ReferenceCounting::Error:
return emitErrorRelease(value);
}
}
void IRGenFunction::emitScalarRetainCall(llvm::Value *value,
ReferenceCounting refcounting) {
switch (refcounting) {
case ReferenceCounting::Native:
emitRetainCall(value);
return;
case ReferenceCounting::Bridge:
emitBridgeRetainCall(value);
return;
case ReferenceCounting::ObjC:
emitObjCRetainCall(value);
return;
case ReferenceCounting::Block:
emitBlockCopyCall(value);
return;
case ReferenceCounting::Unknown:
emitUnknownRetainCall(value);
return;
case ReferenceCounting::Error:
emitErrorRetainCall(value);
return;
}
}
llvm::Type *IRGenModule::getReferenceType(ReferenceCounting refcounting) {
switch (refcounting) {
case ReferenceCounting::Native:
return RefCountedPtrTy;
case ReferenceCounting::Bridge:
return BridgeObjectPtrTy;
case ReferenceCounting::ObjC:
return ObjCPtrTy;
case ReferenceCounting::Block:
return ObjCBlockPtrTy;
case ReferenceCounting::Unknown:
return UnknownRefCountedPtrTy;
case ReferenceCounting::Error:
return ErrorPtrTy;
}
}
/// Emit a release of a live value.
void IRGenFunction::emitRelease(llvm::Value *value) {
if (doesNotRequireRefCounting(value)) return;
emitUnaryRefCountCall(*this, IGM.getReleaseFn(), value);
}
/// Fix the lifetime of a live value. This communicates to the LLVM level ARC
/// optimizer not to touch this value.
void IRGenFunction::emitFixLifetime(llvm::Value *value) {
if (doesNotRequireRefCounting(value)) return;
emitUnaryRefCountCall(*this, IGM.getFixLifetimeFn(), value);
}
void IRGenFunction::emitUnknownRetain(llvm::Value *value, Explosion &e) {
if (!IGM.ObjCInterop) {
emitRetain(value, e);
return;
}
emitUnaryRefCountCall(*this, IGM.getUnknownRetainFn(), value);
}
llvm::Value *IRGenFunction::emitUnknownRetainCall(llvm::Value *value) {
if (!IGM.ObjCInterop) {
emitRetainCall(value);
return value;
}
emitUnaryRefCountCall(*this, IGM.getUnknownRetainFn(), value);
return value;
}
void IRGenFunction::emitUnknownRelease(llvm::Value *value) {
if (!IGM.ObjCInterop) {
emitRelease(value);
return;
}
emitUnaryRefCountCall(*this, IGM.getUnknownReleaseFn(), value);
}
void IRGenFunction::emitBridgeRetain(llvm::Value *value, Explosion &e) {
if (!IGM.ObjCInterop) {
emitRetain(value, e);
return;
}
emitUnaryRefCountCall(*this, IGM.getBridgeObjectRetainFn(), value);
}
llvm::Value *IRGenFunction::emitBridgeRetainCall(llvm::Value *value) {
if (!IGM.ObjCInterop) {
emitRetainCall(value);
return value;
}
emitUnaryRefCountCall(*this, IGM.getBridgeObjectRetainFn(), value);
return value;
}
void IRGenFunction::emitBridgeRelease(llvm::Value *value) {
if (!IGM.ObjCInterop) {
emitRelease(value);
return;
}
emitUnaryRefCountCall(*this, IGM.getBridgeObjectReleaseFn(), value);
}
void IRGenFunction::emitErrorRetain(llvm::Value *value) {
emitUnaryRefCountCall(*this, IGM.getErrorRetainFn(), value);
}
llvm::Value *IRGenFunction::emitErrorRetainCall(llvm::Value *value) {
emitUnaryRefCountCall(*this, IGM.getErrorRetainFn(), value);
return value;
}
void IRGenFunction::emitErrorRelease(llvm::Value *value) {
emitUnaryRefCountCall(*this, IGM.getErrorReleaseFn(), value);
}
llvm::Value *IRGenFunction::emitTryPin(llvm::Value *value) {
llvm::CallInst *call = Builder.CreateCall(IGM.getTryPinFn(), value);
call->setCallingConv(IGM.RuntimeCC);
call->setDoesNotThrow();
// Builtin.NativeObject? has representation i32/i64.
llvm::Value *handle = Builder.CreatePtrToInt(call, IGM.IntPtrTy);