averello/swift-mirror
1
0
Fork 0
mirror of https://github.com/apple/swift.git synced 2025-12-14 20:36:38 +01:00
Code Issues Packages Projects Releases Wiki Activity
Files
e223f1fc9ba8040ea3b2cebb8c7478ffaea7e974
swift-mirror/lib/IRGen/IRGenModule.cpp
Greg Parker e223f1fc9b [IRGen][runtime] Simplify runtime CCs and entry point ABIs (#14175) 
* Remove RegisterPreservingCC. It was unused.
* Remove DefaultCC from the runtime. The distinction between C_CC and DefaultCC
  was unused and inconsistently applied. Separate C_CC and DefaultCC are
  still present in the compiler.
* Remove function pointer indirection from runtime functions except those
  that are used by Instruments. The remaining Instruments interface is
  expected to change later due to function pointer liability.
* Remove swift_rt_ wrappers. Function pointers are an ABI liability that we
  don't want, and there are better ways to get nonlazy binding if we need it.
  The fully custom wrappers were only needed for RegisterPreservingCC and
  for optimizing the Instruments function pointers.
2018-01-29 13:22:30 -08:00

1113 lines
40 KiB
C++
Raw Blame History

//===--- IRGenModule.cpp - Swift Global LLVM IR Generation ----------------===//
//
// 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 for global declarations in Swift.
//
//===----------------------------------------------------------------------===//
#include "swift/AST/ASTContext.h"
#include "swift/AST/Module.h"
#include "swift/AST/DiagnosticsIRGen.h"
#include "swift/AST/IRGenOptions.h"
#include "swift/Basic/Dwarf.h"
#include "swift/Demangling/ManglingMacros.h"
#include "swift/ClangImporter/ClangImporter.h"
#include "swift/IRGen/Linking.h"
#include "swift/Runtime/RuntimeFnWrappersGen.h"
#include "swift/Runtime/Config.h"
#include "clang/AST/ASTContext.h"
#include "clang/Basic/CharInfo.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/CodeGen/CodeGenABITypes.h"
#include "clang/CodeGen/ModuleBuilder.h"
#include "clang/CodeGen/SwiftCallingConv.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Lex/PreprocessorOptions.h"
#include "clang/Lex/HeaderSearch.h"
#include "clang/Lex/HeaderSearchOptions.h"
#include "clang/Frontend/CodeGenOptions.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/MDBuilder.h"
#include "llvm/IR/Module.h"
#include "llvm/IR/Type.h"
#include "llvm/ADT/PointerUnion.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MD5.h"
#include "GenEnum.h"
#include "GenType.h"
#include "IRGenModule.h"
#include "IRGenDebugInfo.h"
#include "StructLayout.h"
#include <initializer_list>
using namespace swift;
using namespace irgen;
using llvm::Attribute;
const unsigned DefaultAS = 0;
/// A helper for creating LLVM struct types.
static llvm::StructType *createStructType(IRGenModule &IGM,
StringRef name,
std::initializer_list<llvm::Type*> types,
bool packed = false) {
return llvm::StructType::create(IGM.getLLVMContext(),
ArrayRef<llvm::Type*>(types.begin(),
types.size()),
name, packed);
};
/// A helper for creating pointer-to-struct types.
static llvm::PointerType *createStructPointerType(IRGenModule &IGM,
StringRef name,
std::initializer_list<llvm::Type*> types) {
return createStructType(IGM, name, types)->getPointerTo(DefaultAS);
};
static clang::CodeGenerator *createClangCodeGenerator(ASTContext &Context,
llvm::LLVMContext &LLVMContext,
IRGenOptions &Opts,
StringRef ModuleName) {
auto Loader = Context.getClangModuleLoader();
auto *Importer = static_cast<ClangImporter*>(&*Loader);
assert(Importer && "No clang module loader!");
auto &ClangContext = Importer->getClangASTContext();
auto &CGO = Importer->getClangCodeGenOpts();
CGO.OptimizationLevel = Opts.shouldOptimize() ? 3 : 0;
CGO.DisableFPElim = Opts.DisableFPElim;
CGO.DiscardValueNames = !Opts.shouldProvideValueNames();
switch (Opts.DebugInfoKind) {
case IRGenDebugInfoKind::None:
CGO.setDebugInfo(clang::codegenoptions::DebugInfoKind::NoDebugInfo);
break;
case IRGenDebugInfoKind::LineTables:
CGO.setDebugInfo(clang::codegenoptions::DebugInfoKind::DebugLineTablesOnly);
break;
case IRGenDebugInfoKind::ASTTypes:
case IRGenDebugInfoKind::DwarfTypes:
CGO.DebugTypeExtRefs = true;
CGO.setDebugInfo(clang::codegenoptions::DebugInfoKind::FullDebugInfo);
break;
}
if (Opts.DebugInfoKind > IRGenDebugInfoKind::None) {
CGO.DebugCompilationDir = Opts.DebugCompilationDir;
CGO.DwarfVersion = Opts.DWARFVersion;
CGO.DwarfDebugFlags = Opts.DWARFDebugFlags;
}
auto &HSI = Importer->getClangPreprocessor()
.getHeaderSearchInfo()
.getHeaderSearchOpts();
auto &PPO = Importer->getClangPreprocessor().getPreprocessorOpts();
auto *ClangCodeGen = clang::CreateLLVMCodeGen(ClangContext.getDiagnostics(),
ModuleName, HSI, PPO, CGO,
LLVMContext);
ClangCodeGen->Initialize(ClangContext);
return ClangCodeGen;
}
IRGenModule::IRGenModule(IRGenerator &irgen,
std::unique_ptr<llvm::TargetMachine> &&target,
SourceFile *SF, llvm::LLVMContext &LLVMContext,
StringRef ModuleName, StringRef OutputFilename)
: IRGen(irgen), Context(irgen.SIL.getASTContext()),
ClangCodeGen(createClangCodeGenerator(Context, LLVMContext, irgen.Opts,
ModuleName)),
Module(*ClangCodeGen->GetModule()), LLVMContext(Module.getContext()),
DataLayout(target->createDataLayout()), Triple(Context.LangOpts.Target),
TargetMachine(std::move(target)), silConv(irgen.SIL),
OutputFilename(OutputFilename),
TargetInfo(SwiftTargetInfo::get(*this)), DebugInfo(nullptr),
ModuleHash(nullptr), ObjCInterop(Context.LangOpts.EnableObjCInterop),
UseDarwinPreStableABIBit(Context.LangOpts.UseDarwinPreStableABIBit),
Types(*new TypeConverter(*this)) {
irgen.addGenModule(SF, this);
auto &opts = irgen.Opts;
EnableValueNames = opts.shouldProvideValueNames();
VoidTy = llvm::Type::getVoidTy(getLLVMContext());
Int1Ty = llvm::Type::getInt1Ty(getLLVMContext());
Int8Ty = llvm::Type::getInt8Ty(getLLVMContext());
Int16Ty = llvm::Type::getInt16Ty(getLLVMContext());
Int32Ty = llvm::Type::getInt32Ty(getLLVMContext());
Int32PtrTy = Int32Ty->getPointerTo();
Int64Ty = llvm::Type::getInt64Ty(getLLVMContext());
Int8PtrTy = llvm::Type::getInt8PtrTy(getLLVMContext());
Int8PtrPtrTy = Int8PtrTy->getPointerTo(0);
SizeTy = DataLayout.getIntPtrType(getLLVMContext(), /*addrspace*/ 0);
auto CI = static_cast<ClangImporter*>(&*Context.getClangModuleLoader());
assert(CI && "no clang module loader");
auto &clangASTContext = CI->getClangASTContext();
ObjCBoolTy = Int1Ty;
if (clangASTContext.getTargetInfo().useSignedCharForObjCBool())
ObjCBoolTy = Int8Ty;
RefCountedStructTy =
llvm::StructType::create(getLLVMContext(), "swift.refcounted");
RefCountedPtrTy = RefCountedStructTy->getPointerTo(/*addrspace*/ 0);
RefCountedNull = llvm::ConstantPointerNull::get(RefCountedPtrTy);
// For now, native weak references are just a pointer.
WeakReferencePtrTy =
createStructPointerType(*this, "swift.weak", { RefCountedPtrTy });
// Native unowned references are just a pointer.
UnownedReferencePtrTy =
createStructPointerType(*this, "swift.unowned", { RefCountedPtrTy });
// A type metadata record is the structure pointed to by the canonical
// address point of a type metadata. This is at least one word, and
// potentially more than that, past the start of the actual global
// structure.
TypeMetadataStructTy = createStructType(*this, "swift.type", {
MetadataKindTy // MetadataKind Kind;
});
TypeMetadataPtrTy = TypeMetadataStructTy->getPointerTo(DefaultAS);
// A protocol descriptor describes a protocol. It is not type metadata in
// and of itself, but is referenced in the structure of existential type
// metadata records.
ProtocolDescriptorStructTy = createStructType(*this, "swift.protocol", {
Int8PtrTy, // objc isa
Int8PtrTy, // name
Int8PtrTy, // inherited protocols
Int8PtrTy, // required objc instance methods
Int8PtrTy, // required objc class methods
Int8PtrTy, // optional objc instance methods
Int8PtrTy, // optional objc class methods
Int8PtrTy, // objc properties
Int32Ty, // size
Int32Ty, // flags
Int16Ty, // mandatory requirement count
Int16Ty, // total requirement count
Int32Ty, // requirements array
RelativeAddressTy, // superclass
RelativeAddressTy // associated type names
});
ProtocolDescriptorPtrTy = ProtocolDescriptorStructTy->getPointerTo();
ProtocolRequirementStructTy =
createStructType(*this, "swift.protocol_requirement", {
Int32Ty, // flags
Int32Ty // default implementation
});
// A tuple type metadata record has a couple extra fields.
auto tupleElementTy = createStructType(*this, "swift.tuple_element_type", {
TypeMetadataPtrTy, // Metadata *Type;
SizeTy // size_t Offset;
});
TupleTypeMetadataPtrTy = createStructPointerType(*this, "swift.tuple_type", {
TypeMetadataStructTy, // (base)
SizeTy, // size_t NumElements;
Int8PtrTy, // const char *Labels;
llvm::ArrayType::get(tupleElementTy, 0) // Element Elements[];
});
// A full type metadata record is basically just an adjustment to the
// address point of a type metadata. Resilience may cause
// additional data to be laid out prior to this address point.
FullTypeMetadataStructTy = createStructType(*this, "swift.full_type", {
WitnessTablePtrTy,
TypeMetadataStructTy
});
FullTypeMetadataPtrTy = FullTypeMetadataStructTy->getPointerTo(DefaultAS);
// A metadata pattern is a structure from which generic type
// metadata are allocated. We leave this struct type intentionally
// opaque, because the compiler basically never needs to access
// anything from one.
TypeMetadataPatternStructTy =
llvm::StructType::create(getLLVMContext(), "swift.type_pattern");
TypeMetadataPatternPtrTy =
TypeMetadataPatternStructTy->getPointerTo(DefaultAS);
DeallocatingDtorTy = llvm::FunctionType::get(VoidTy, RefCountedPtrTy, false);
llvm::Type *dtorPtrTy = DeallocatingDtorTy->getPointerTo();
// A full heap metadata is basically just an additional small prefix
// on a full metadata, used for metadata corresponding to heap
// allocations.
FullHeapMetadataStructTy =
createStructType(*this, "swift.full_heapmetadata", {
dtorPtrTy,
WitnessTablePtrTy,
TypeMetadataStructTy
});
FullHeapMetadataPtrTy = FullHeapMetadataStructTy->getPointerTo(DefaultAS);
// A full box metadata is non-type heap metadata for a heap allocation of a
// single value. The box tracks the offset to the value inside the box.
FullBoxMetadataStructTy =
createStructType(*this, "swift.full_boxmetadata", {
dtorPtrTy,
WitnessTablePtrTy,
TypeMetadataStructTy,
Int32Ty,
CaptureDescriptorPtrTy,
});
FullBoxMetadataPtrTy = FullBoxMetadataStructTy->getPointerTo(DefaultAS);
// This must match struct HeapObject in the runtime.
llvm::Type *refCountedElts[] = {TypeMetadataPtrTy, IntPtrTy};
RefCountedStructTy->setBody(refCountedElts);
RefCountedStructSize =
Size(DataLayout.getStructLayout(RefCountedStructTy)->getSizeInBytes());
PtrSize = Size(DataLayout.getPointerSize(DefaultAS));
FunctionPairTy = createStructType(*this, "swift.function", {
FunctionPtrTy,
RefCountedPtrTy,
});
OpaqueTy = llvm::StructType::create(LLVMContext, "swift.opaque");
OpaquePtrTy = OpaqueTy->getPointerTo(DefaultAS);
ProtocolRecordTy =
createStructType(*this, "swift.protocolref", {
RelativeAddressTy
});
ProtocolRecordPtrTy = ProtocolRecordTy->getPointerTo();
ProtocolConformanceDescriptorTy
= createStructType(*this, "swift.protocol_conformance_descriptor", {
RelativeAddressTy,
RelativeAddressTy,
RelativeAddressTy,
Int32Ty
});
ProtocolConformanceDescriptorPtrTy
= ProtocolConformanceDescriptorTy->getPointerTo(DefaultAS);
NominalTypeDescriptorTy
= llvm::StructType::create(LLVMContext, "swift.type_descriptor");
NominalTypeDescriptorPtrTy
= NominalTypeDescriptorTy->getPointerTo(DefaultAS);
ClassNominalTypeDescriptorTy =
llvm::StructType::get(LLVMContext, {
Int32Ty,
Int32Ty,
Int32Ty,
Int32Ty,
Int32Ty,
Int32Ty,
Int32Ty,
Int32Ty,
Int32Ty,
Int32Ty,
Int16Ty,
Int16Ty,
Int32Ty,
}, /*packed=*/true);
MethodDescriptorStructTy
= createStructType(*this, "swift.method_descriptor", {
RelativeAddressTy,
Int32Ty
});
TypeMetadataRecordTy
= createStructType(*this, "swift.type_metadata_record", {
RelativeAddressTy
});
TypeMetadataRecordPtrTy
= TypeMetadataRecordTy->getPointerTo(DefaultAS);
FieldDescriptorTy
= llvm::StructType::create(LLVMContext, "swift.field_descriptor");
FieldDescriptorPtrTy = FieldDescriptorTy->getPointerTo(DefaultAS);
FixedBufferTy = nullptr;
for (unsigned i = 0; i != MaxNumValueWitnesses; ++i)
ValueWitnessTys[i] = nullptr;
ObjCPtrTy = llvm::StructType::create(getLLVMContext(), "objc_object")
->getPointerTo(DefaultAS);
BridgeObjectPtrTy = llvm::StructType::create(getLLVMContext(), "swift.bridge")
->getPointerTo(DefaultAS);
ObjCClassStructTy = llvm::StructType::create(LLVMContext, "objc_class");
ObjCClassPtrTy = ObjCClassStructTy->getPointerTo(DefaultAS);
llvm::Type *objcClassElts[] = {
ObjCClassPtrTy,
ObjCClassPtrTy,
OpaquePtrTy,
OpaquePtrTy,
IntPtrTy
};
ObjCClassStructTy->setBody(objcClassElts);
ObjCSuperStructTy = llvm::StructType::create(LLVMContext, "objc_super");
ObjCSuperPtrTy = ObjCSuperStructTy->getPointerTo(DefaultAS);
llvm::Type *objcSuperElts[] = {
ObjCPtrTy,
ObjCClassPtrTy
};
ObjCSuperStructTy->setBody(objcSuperElts);
ObjCBlockStructTy = llvm::StructType::create(LLVMContext, "objc_block");
ObjCBlockPtrTy = ObjCBlockStructTy->getPointerTo(DefaultAS);
llvm::Type *objcBlockElts[] = {
ObjCClassPtrTy, // isa
Int32Ty, // flags
Int32Ty, // reserved
FunctionPtrTy, // invoke function pointer
Int8PtrTy, // TODO: block descriptor pointer.
// We will probably need a struct type for that at some
// point too.
};
ObjCBlockStructTy->setBody(objcBlockElts);
auto ErrorStructTy = llvm::StructType::create(LLVMContext, "swift.error");
// ErrorStruct is currently opaque to the compiler.
ErrorPtrTy = ErrorStructTy->getPointerTo(DefaultAS);
llvm::Type *openedErrorTriple[] = {
OpaquePtrTy,
TypeMetadataPtrTy,
WitnessTablePtrTy,
};
OpenedErrorTripleTy = llvm::StructType::get(getLLVMContext(),
openedErrorTriple,
/*packed*/ false);
OpenedErrorTriplePtrTy = OpenedErrorTripleTy->getPointerTo(DefaultAS);
WitnessTablePtrPtrTy = WitnessTablePtrTy->getPointerTo(DefaultAS);
WitnessTableSliceTy = createStructType(*this, "swift.witness_table_slice",
{WitnessTablePtrPtrTy, SizeTy});
InvariantMetadataID = LLVMContext.getMDKindID("invariant.load");
InvariantNode = llvm::MDNode::get(LLVMContext, {});
DereferenceableID = LLVMContext.getMDKindID("dereferenceable");
C_CC = llvm::CallingConv::C;
// TODO: use "tinycc" on platforms that support it
DefaultCC = SWIFT_DEFAULT_LLVM_CC;
SwiftCC = llvm::CallingConv::Swift;
if (IRGen.Opts.DebugInfoKind > IRGenDebugInfoKind::None)
DebugInfo = IRGenDebugInfo::createIRGenDebugInfo(IRGen.Opts, *CI, *this,
Module, SF);
initClangTypeConverter();
if (ClangASTContext) {
auto atomicBoolTy = ClangASTContext->getAtomicType(ClangASTContext->BoolTy);
AtomicBoolSize = Size(ClangASTContext->getTypeSize(atomicBoolTy));
AtomicBoolAlign = Alignment(ClangASTContext->getTypeSize(atomicBoolTy));
}
IsSwiftErrorInRegister =
clang::CodeGen::swiftcall::isSwiftErrorLoweredInRegister(
ClangCodeGen->CGM());
}
IRGenModule::~IRGenModule() {
destroyClangTypeConverter();
destroyMetadataLayoutMap();
delete &Types;
delete DebugInfo;
}
static bool isReturnAttribute(llvm::Attribute::AttrKind Attr);
// Explicitly listing these constants is an unfortunate compromise for
// making the database file much more compact.
//
// They have to be non-local because otherwise we'll get warnings when
// a particular x-macro expansion doesn't use one.
namespace RuntimeConstants {
const auto ReadNone = llvm::Attribute::ReadNone;
const auto ReadOnly = llvm::Attribute::ReadOnly;
const auto NoReturn = llvm::Attribute::NoReturn;
const auto NoUnwind = llvm::Attribute::NoUnwind;
const auto ZExt = llvm::Attribute::ZExt;
const auto FirstParamReturned = llvm::Attribute::Returned;
} // namespace RuntimeConstants
// We don't use enough attributes to justify generalizing the
// RuntimeFunctions.def FUNCTION macro. Instead, special case the one attribute
// associated with the return type not the function type.
static bool isReturnAttribute(llvm::Attribute::AttrKind Attr) {
return Attr == llvm::Attribute::ZExt;
}
// Similar to the 'return' attribute we assume that the 'returned' attributed is
// associated with the first function parameter.
static bool isReturnedAttribute(llvm::Attribute::AttrKind Attr) {
return Attr == llvm::Attribute::Returned;
}
llvm::Constant *swift::getRuntimeFn(llvm::Module &Module,
llvm::Constant *&cache,
const char *name,
llvm::CallingConv::ID cc,
llvm::ArrayRef<llvm::Type*> retTypes,
llvm::ArrayRef<llvm::Type*> argTypes,
ArrayRef<Attribute::AttrKind> attrs) {
if (cache)
return cache;
llvm::Type *retTy;
if (retTypes.size() == 1)
retTy = *retTypes.begin();
else
retTy = llvm::StructType::get(Module.getContext(),
{retTypes.begin(), retTypes.end()},
/*packed*/ false);
auto fnTy = llvm::FunctionType::get(retTy,
{argTypes.begin(), argTypes.end()},
/*isVararg*/ false);
cache = Module.getOrInsertFunction(name, fnTy);
// Add any function attributes and set the calling convention.
if (auto fn = dyn_cast<llvm::Function>(cache)) {
fn->setCallingConv(cc);
if (::useDllStorage(llvm::Triple(Module.getTargetTriple())) &&
((fn->getLinkage() == llvm::GlobalValue::ExternalLinkage &&
fn->isDeclaration()) ||
fn->getLinkage() == llvm::GlobalValue::AvailableExternallyLinkage))
fn->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
llvm::AttrBuilder buildFnAttr;
llvm::AttrBuilder buildRetAttr;
llvm::AttrBuilder buildFirstParamAttr;
for (auto Attr : attrs) {
if (isReturnAttribute(Attr))
buildRetAttr.addAttribute(Attr);
else if (isReturnedAttribute(Attr))
buildFirstParamAttr.addAttribute(Attr);
else
buildFnAttr.addAttribute(Attr);
}
fn->addAttributes(llvm::AttributeList::FunctionIndex, buildFnAttr);
fn->addAttributes(llvm::AttributeList::ReturnIndex, buildRetAttr);
fn->addParamAttrs(0, buildFirstParamAttr);
}
return cache;
}
#define QUOTE(...) __VA_ARGS__
#define STR(X) #X
#define FUNCTION(ID, NAME, CC, RETURNS, ARGS, ATTRS) \
FUNCTION_IMPL(ID, NAME, CC, QUOTE(RETURNS), QUOTE(ARGS), QUOTE(ATTRS))
#define RETURNS(...) { __VA_ARGS__ }
#define ARGS(...) { __VA_ARGS__ }
#define NO_ARGS {}
#define ATTRS(...) { __VA_ARGS__ }
#define NO_ATTRS {}
#define FUNCTION_IMPL(ID, NAME, CC, RETURNS, ARGS, ATTRS) \
llvm::Constant *IRGenModule::get##ID##Fn() { \
using namespace RuntimeConstants; \
return getRuntimeFn(Module, ID##Fn, #NAME, CC, RETURNS, ARGS, ATTRS); \
}
#include "swift/Runtime/RuntimeFunctions.def"
std::pair<llvm::GlobalVariable *, llvm::Constant *>
IRGenModule::createStringConstant(StringRef Str,
bool willBeRelativelyAddressed, StringRef sectionName) {
// If not, create it. This implicitly adds a trailing null.
auto init = llvm::ConstantDataArray::getString(LLVMContext, Str);
auto global = new llvm::GlobalVariable(Module, init->getType(), true,
llvm::GlobalValue::PrivateLinkage,
init);
// FIXME: ld64 crashes resolving relative references to coalesceable symbols.
// rdar://problem/22674524
// If we intend to relatively address this string, don't mark it with
// unnamed_addr to prevent it from going into the cstrings section and getting
// coalesced.
if (!willBeRelativelyAddressed)
global->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
if (!sectionName.empty())
global->setSection(sectionName);
// Drill down to make an i8*.
auto zero = llvm::ConstantInt::get(SizeTy, 0);
llvm::Constant *indices[] = { zero, zero };
auto address = llvm::ConstantExpr::getInBoundsGetElementPtr(
global->getValueType(), global, indices);
return { global, address };
}
llvm::Constant *IRGenModule::getEmptyTupleMetadata() {
if (EmptyTupleMetadata)
return EmptyTupleMetadata;
EmptyTupleMetadata = Module.getOrInsertGlobal(
MANGLE_AS_STRING(METADATA_SYM(EMPTY_TUPLE_MANGLING)),
FullTypeMetadataStructTy);
if (useDllStorage())
cast<llvm::GlobalVariable>(EmptyTupleMetadata)
->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
return EmptyTupleMetadata;
}
llvm::Constant *IRGenModule::getObjCEmptyCachePtr() {
if (ObjCEmptyCachePtr)
return ObjCEmptyCachePtr;
if (ObjCInterop) {
// struct objc_cache _objc_empty_cache;
ObjCEmptyCachePtr = Module.getOrInsertGlobal("_objc_empty_cache",
OpaquePtrTy->getElementType());
if (useDllStorage())
cast<llvm::GlobalVariable>(ObjCEmptyCachePtr)
->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
} else {
// FIXME: Remove even the null value per rdar://problem/18801263
ObjCEmptyCachePtr = llvm::ConstantPointerNull::get(OpaquePtrTy);
}
return ObjCEmptyCachePtr;
}
llvm::Constant *IRGenModule::getObjCEmptyVTablePtr() {
// IMP _objc_empty_vtable;
// On recent Darwin platforms, this symbol is defined at
// runtime as an absolute symbol with the value of null. Older ObjCs
// didn't guarantee _objc_empty_vtable to be nil, but Swift doesn't
// deploy far enough back for that to be a concern.
// FIXME: When !ObjCInterop, we should remove even the null value per
// rdar://problem/18801263
if (!ObjCEmptyVTablePtr)
ObjCEmptyVTablePtr = llvm::ConstantPointerNull::get(OpaquePtrTy);
return ObjCEmptyVTablePtr;
}
Address IRGenModule::getAddrOfObjCISAMask() {
// This symbol is only exported by the runtime if the platform uses
// isa masking.
assert(TargetInfo.hasISAMasking());
if (!ObjCISAMaskPtr) {
ObjCISAMaskPtr = Module.getOrInsertGlobal("swift_isaMask", IntPtrTy);
if (useDllStorage())
cast<llvm::GlobalVariable>(ObjCISAMaskPtr)
->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
}
return Address(ObjCISAMaskPtr, getPointerAlignment());
}
ModuleDecl *IRGenModule::getSwiftModule() const {
return IRGen.SIL.getSwiftModule();
}
Lowering::TypeConverter &IRGenModule::getSILTypes() const {
return IRGen.SIL.Types;
}
clang::CodeGen::CodeGenModule &IRGenModule::getClangCGM() const {
return ClangCodeGen->CGM();
}
llvm::Module *IRGenModule::getModule() const {
return ClangCodeGen->GetModule();
}
llvm::Module *IRGenModule::releaseModule() {
return ClangCodeGen->ReleaseModule();
}
bool IRGenerator::canEmitWitnessTableLazily(SILWitnessTable *wt) {
if (Opts.UseJIT)
return false;
NominalTypeDecl *ConformingTy =
wt->getConformance()->getType()->getNominalOrBoundGenericNominal();
switch (ConformingTy->getEffectiveAccess()) {
case AccessLevel::Private:
case AccessLevel::FilePrivate:
return true;
case AccessLevel::Internal:
return PrimaryIGM->getSILModule().isWholeModule();
default:
return false;
}
llvm_unreachable("switch does not handle all cases");
}
void IRGenerator::addLazyWitnessTable(const ProtocolConformance *Conf) {
if (SILWitnessTable *wt = SIL.lookUpWitnessTable(Conf)) {
// Add it to the queue if it hasn't already been put there.
if (canEmitWitnessTableLazily(wt) &&
LazilyEmittedWitnessTables.insert(wt).second) {
LazyWitnessTables.push_back(wt);
}
}
}
void IRGenerator::addClassForEagerInitialization(ClassDecl *ClassDecl) {
if (!ClassDecl->getAttrs().hasAttribute<StaticInitializeObjCMetadataAttr>())
return;
// Exclude some classes where those attributes make no sense but could be set
// for some reason. Just to be on the safe side.
Type ClassTy = ClassDecl->getDeclaredType();
if (ClassTy->is<UnboundGenericType>())
return;
if (ClassTy->hasArchetype())
return;
if (ClassDecl->hasClangNode())
return;
ClassesForEagerInitialization.push_back(ClassDecl);
}
llvm::AttributeList IRGenModule::getAllocAttrs() {
if (AllocAttrs.isEmpty()) {
AllocAttrs =
llvm::AttributeList::get(LLVMContext, llvm::AttributeList::ReturnIndex,
llvm::Attribute::NoAlias);
AllocAttrs =
AllocAttrs.addAttribute(LLVMContext, llvm::AttributeList::FunctionIndex,
llvm::Attribute::NoUnwind);
}
return AllocAttrs;
}
/// Disable thumb-mode until debugger support is there.
bool swift::irgen::shouldRemoveTargetFeature(StringRef feature) {
return feature == "+thumb-mode";
}
/// Construct initial function attributes from options.
void IRGenModule::constructInitialFnAttributes(llvm::AttrBuilder &Attrs,
OptimizationMode FuncOptMode) {
// Add DisableFPElim.
if (!IRGen.Opts.DisableFPElim) {
Attrs.addAttribute("no-frame-pointer-elim", "false");
} else {
Attrs.addAttribute("no-frame-pointer-elim", "true");
Attrs.addAttribute("no-frame-pointer-elim-non-leaf");
}
// Add target-cpu and target-features if they are non-null.
auto *Clang = static_cast<ClangImporter *>(Context.getClangModuleLoader());
clang::TargetOptions &ClangOpts = Clang->getTargetInfo().getTargetOpts();
std::string &CPU = ClangOpts.CPU;
if (CPU != "")
Attrs.addAttribute("target-cpu", CPU);
std::vector<std::string> Features;
for (auto &F : ClangOpts.Features)
if (!shouldRemoveTargetFeature(F))
Features.push_back(F);
if (!Features.empty()) {
SmallString<64> allFeatures;
// Sort so that the target features string is canonical.
std::sort(Features.begin(), Features.end());
interleave(Features, [&](const std::string &s) {
allFeatures.append(s);
}, [&]{
allFeatures.push_back(',');
});
Attrs.addAttribute("target-features", allFeatures);
}
if (FuncOptMode == OptimizationMode::NotSet)
FuncOptMode = IRGen.Opts.OptMode;
if (FuncOptMode == OptimizationMode::ForSize)
Attrs.addAttribute(llvm::Attribute::MinSize);
}
llvm::AttributeList IRGenModule::constructInitialAttributes() {
llvm::AttrBuilder b;
constructInitialFnAttributes(b);
return llvm::AttributeList::get(LLVMContext,
llvm::AttributeList::FunctionIndex, b);
}
llvm::Constant *IRGenModule::getSize(Size size) {
return llvm::ConstantInt::get(SizeTy, size.getValue());
}
llvm::Constant *IRGenModule::getOpaquePtr(llvm::Constant *ptr) {
return llvm::ConstantExpr::getBitCast(ptr, Int8PtrTy);
}
static void appendEncodedName(raw_ostream &os, StringRef name) {
if (clang::isValidIdentifier(name)) {
os << "_" << name;
} else {
for (auto c : name)
os.write_hex(static_cast<uint8_t>(c));
}
}
static void appendEncodedName(llvm::SmallVectorImpl<char> &buf,
StringRef name) {
llvm::raw_svector_ostream os{buf};
appendEncodedName(os, name);
}
static StringRef encodeForceLoadSymbolName(llvm::SmallVectorImpl<char> &buf,
StringRef name) {
llvm::raw_svector_ostream os{buf};
os << "_swift_FORCE_LOAD_$";
appendEncodedName(os, name);
return os.str();
}
llvm::SmallString<32> getTargetDependentLibraryOption(const llvm::Triple &T,
StringRef library) {
llvm::SmallString<32> buffer;
if (T.isWindowsMSVCEnvironment() || T.isWindowsItaniumEnvironment()) {
bool quote = library.find(' ') != StringRef::npos;
buffer += "/DEFAULTLIB:";
if (quote)
buffer += '"';
buffer += library;
if (!library.endswith_lower(".lib"))
buffer += ".lib";
if (quote)
buffer += '"';
} else if (T.isPS4()) {
bool quote = library.find(' ') != StringRef::npos;
buffer += "\01";
if (quote)
buffer += '"';
buffer += library;
if (quote)
buffer += '"';
} else {
buffer += "-l";
buffer += library;
}
return buffer;
}
void IRGenModule::addLinkLibrary(const LinkLibrary &linkLib) {
llvm::LLVMContext &ctx = Module.getContext();
switch (linkLib.getKind()) {
case LibraryKind::Library: {
llvm::SmallString<32> opt =
getTargetDependentLibraryOption(Triple, linkLib.getName());
AutolinkEntries.push_back(
llvm::MDNode::get(ctx, llvm::MDString::get(ctx, opt)));
break;
}
case LibraryKind::Framework: {
// If we're supposed to disable autolinking of this framework, bail out.
auto &frameworks = IRGen.Opts.DisableAutolinkFrameworks;
if (std::find(frameworks.begin(), frameworks.end(), linkLib.getName())
!= frameworks.end())
return;
llvm::Metadata *args[] = {
llvm::MDString::get(ctx, "-framework"),
llvm::MDString::get(ctx, linkLib.getName())
};
AutolinkEntries.push_back(llvm::MDNode::get(ctx, args));
break;
}
}
if (linkLib.shouldForceLoad()) {
llvm::SmallString<64> buf;
encodeForceLoadSymbolName(buf, linkLib.getName());
auto symbolAddr = Module.getOrInsertGlobal(buf.str(), Int1Ty);
if (useDllStorage())
cast<llvm::GlobalVariable>(symbolAddr)
->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
buf += "_$";
appendEncodedName(buf, IRGen.Opts.ModuleName);
if (!Module.getGlobalVariable(buf.str())) {
auto ref = new llvm::GlobalVariable(Module, symbolAddr->getType(),
/*isConstant=*/true,
llvm::GlobalValue::WeakAnyLinkage,
symbolAddr, buf.str());
ref->setVisibility(llvm::GlobalValue::HiddenVisibility);
auto casted = llvm::ConstantExpr::getBitCast(ref, Int8PtrTy);
LLVMUsed.push_back(casted);
}
}
}
static bool replaceModuleFlagsEntry(llvm::LLVMContext &Ctx,
llvm::Module &Module, StringRef EntryName,
llvm::Module::ModFlagBehavior Behavior,
llvm::Metadata *Val) {
auto *ModuleFlags = Module.getModuleFlagsMetadata();
for (unsigned I = 0, E = ModuleFlags->getNumOperands(); I != E; ++I) {
llvm::MDNode *Op = ModuleFlags->getOperand(I);
llvm::MDString *ID = cast<llvm::MDString>(Op->getOperand(1));
if (ID->getString().equals(EntryName)) {
// Create the new entry.
llvm::Type *Int32Ty = llvm::Type::getInt32Ty(Ctx);
llvm::Metadata *Ops[3] = {llvm::ConstantAsMetadata::get(
llvm::ConstantInt::get(Int32Ty, Behavior)),
llvm::MDString::get(Ctx, EntryName), Val};
ModuleFlags->setOperand(I, llvm::MDNode::get(Ctx, Ops));
return true;
}
}
llvm_unreachable("Could not replace old linker options entry?");
}
void IRGenModule::emitAutolinkInfo() {
// Collect the linker options already in the module (from ClangCodeGen).
// FIXME: This constant should be vended by LLVM somewhere.
auto *Metadata = Module.getOrInsertNamedMetadata("llvm.linker.options");
for (llvm::MDNode *LinkOption : Metadata->operands())
AutolinkEntries.push_back(LinkOption);
// Remove duplicates.
llvm::SmallPtrSet<llvm::MDNode *, 4> knownAutolinkEntries;
AutolinkEntries.erase(std::remove_if(AutolinkEntries.begin(),
AutolinkEntries.end(),
[&](llvm::MDNode *entry) -> bool {
return !knownAutolinkEntries.insert(
entry).second;
}),
AutolinkEntries.end());
if ((TargetInfo.OutputObjectFormat == llvm::Triple::COFF &&
!Triple.isOSCygMing()) ||
TargetInfo.OutputObjectFormat == llvm::Triple::MachO || Triple.isPS4()) {
// On platforms that support autolinking, continue to use the metadata.
Metadata->clearOperands();
for (auto *Entry : AutolinkEntries)
Metadata->addOperand(Entry);
} else {
assert((TargetInfo.OutputObjectFormat == llvm::Triple::ELF ||
Triple.isOSCygMing()) &&
"expected ELF output format or COFF format for Cygwin/MinGW");
// Merge the entries into null-separated string.
llvm::SmallString<64> EntriesString;
for (auto &EntryNode : AutolinkEntries) {
const llvm::MDNode *MD = cast<llvm::MDNode>(EntryNode);
for (auto &Entry : MD->operands()) {
const llvm::MDString *MS = cast<llvm::MDString>(Entry);
EntriesString += MS->getString();
EntriesString += '\0';
}
}
auto EntriesConstant = llvm::ConstantDataArray::getString(
LLVMContext, EntriesString, /*AddNull=*/false);
auto var =
new llvm::GlobalVariable(*getModule(), EntriesConstant->getType(), true,
llvm::GlobalValue::PrivateLinkage,
EntriesConstant, "_swift1_autolink_entries");
var->setSection(".swift1_autolink_entries");
var->setAlignment(getPointerAlignment().getValue());
addUsedGlobal(var);
}
if (!IRGen.Opts.ForceLoadSymbolName.empty()) {
llvm::SmallString<64> buf;
encodeForceLoadSymbolName(buf, IRGen.Opts.ForceLoadSymbolName);
auto symbol =
new llvm::GlobalVariable(Module, Int1Ty, /*isConstant=*/false,
llvm::GlobalValue::CommonLinkage,
llvm::Constant::getNullValue(Int1Ty),
buf.str());
if (useDllStorage())
symbol->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
}
}
void IRGenModule::cleanupClangCodeGenMetadata() {
// Remove llvm.ident that ClangCodeGen might have left in the module.
auto *LLVMIdent = Module.getNamedMetadata("llvm.ident");
if (LLVMIdent)
Module.eraseNamedMetadata(LLVMIdent);
// LLVM's object-file emission collects a fixed set of keys for the
// image info.
// Using "Objective-C Garbage Collection" as the key here is a hack,
// but LLVM's object-file emission isn't general enough to collect
// arbitrary keys to put in the image info.
const char *ObjectiveCGarbageCollection = "Objective-C Garbage Collection";
if (Module.getModuleFlag(ObjectiveCGarbageCollection)) {
bool FoundOldEntry = replaceModuleFlagsEntry(
Module.getContext(), Module, ObjectiveCGarbageCollection,
llvm::Module::Override,
llvm::ConstantAsMetadata::get(
llvm::ConstantInt::get(Int32Ty, (uint32_t)(swiftVersion << 8))));
(void)FoundOldEntry;
assert(FoundOldEntry && "Could not replace old module flag entry?");
} else
Module.addModuleFlag(llvm::Module::Override,
ObjectiveCGarbageCollection,
(uint32_t)(swiftVersion << 8));
}
bool IRGenModule::finalize() {
const char *ModuleHashVarName = "llvm.swift_module_hash";
if (IRGen.Opts.OutputKind == IRGenOutputKind::ObjectFile &&
!Module.getGlobalVariable(ModuleHashVarName)) {
// Create a global variable into which we will store the hash of the
// module (used for incremental compilation).
// We have to create the variable now (before we emit the global lists).
// But we want to calculate the hash later because later we can do it
// multi-threaded.
llvm::MD5::MD5Result zero{};
ArrayRef<uint8_t> ZeroArr(reinterpret_cast<uint8_t *>(&zero), sizeof(zero));
auto *ZeroConst = llvm::ConstantDataArray::get(Module.getContext(), ZeroArr);
ModuleHash = new llvm::GlobalVariable(Module, ZeroConst->getType(), true,
llvm::GlobalValue::PrivateLinkage,
ZeroConst, ModuleHashVarName);
switch (TargetInfo.OutputObjectFormat) {
case llvm::Triple::MachO:
// On Darwin the linker ignores the __LLVM segment.
ModuleHash->setSection("__LLVM,__swift_modhash");
break;
case llvm::Triple::ELF:
case llvm::Triple::COFF:
ModuleHash->setSection(".swift_modhash");
break;
default:
llvm_unreachable("Don't know how to emit the module hash for the selected"
"object format.");
}
addUsedGlobal(ModuleHash);
}
emitLazyPrivateDefinitions();
// Finalize clang IR-generation.
finalizeClangCodeGen();
// If that failed, report failure up and skip the final clean-up.
if (!ClangCodeGen->GetModule())
return false;
emitAutolinkInfo();
emitGlobalLists();
if (DebugInfo)
DebugInfo->finalize();
cleanupClangCodeGenMetadata();
return true;
}
/// Emit lazy definitions that have to be emitted in this specific
/// IRGenModule.
void IRGenModule::emitLazyPrivateDefinitions() {
emitLazyObjCProtocolDefinitions();
}
llvm::MDNode *IRGenModule::createProfileWeights(uint64_t TrueCount,
uint64_t FalseCount) const {
uint64_t MaxWeight = std::max(TrueCount, FalseCount);
uint64_t Scale = (MaxWeight > UINT32_MAX) ? UINT32_MAX : 1;
uint32_t ScaledTrueCount = (TrueCount / Scale) + 1;
uint32_t ScaledFalseCount = (FalseCount / Scale) + 1;
llvm::MDBuilder MDHelper(getLLVMContext());
return MDHelper.createBranchWeights(ScaledTrueCount, ScaledFalseCount);
}
void IRGenModule::unimplemented(SourceLoc loc, StringRef message) {
Context.Diags.diagnose(loc, diag::irgen_unimplemented, message);
}
void IRGenModule::fatal_unimplemented(SourceLoc loc, StringRef message) {
Context.Diags.diagnose(loc, diag::irgen_unimplemented, message);
llvm::report_fatal_error(llvm::Twine("unimplemented IRGen feature! ") +
message);
}
void IRGenModule::error(SourceLoc loc, const Twine &message) {
SmallVector<char, 128> buffer;
Context.Diags.diagnose(loc, diag::irgen_failure,
message.toStringRef(buffer));
}
bool IRGenModule::useDllStorage() { return ::useDllStorage(Triple); }
void IRGenerator::addGenModule(SourceFile *SF, IRGenModule *IGM) {
assert(GenModules.count(SF) == 0);
GenModules[SF] = IGM;
if (!PrimaryIGM) {
PrimaryIGM = IGM;
}
Queue.push_back(IGM);
}
IRGenModule *IRGenerator::getGenModule(DeclContext *ctxt) {
if (GenModules.size() == 1 || !ctxt) {
return getPrimaryIGM();
}
SourceFile *SF = ctxt->getParentSourceFile();
if (!SF) {
return getPrimaryIGM();
}
IRGenModule *IGM = GenModules[SF];
assert(IGM);
return IGM;
}
IRGenModule *IRGenerator::getGenModule(SILFunction *f) {
if (GenModules.size() == 1) {
return getPrimaryIGM();
}
if (DeclContext *ctxt = f->getDeclContext()) {
if (SourceFile *SF = ctxt->getParentSourceFile()) {
IRGenModule *IGM = GenModules[SF];
assert(IGM);
return IGM;
}
}
// We have no source file for the function.
// Let's use the IGM from which the function is referenced the first time.
if (IRGenModule *IGM = DefaultIGMForFunction[f])
return IGM;
return getPrimaryIGM();
}
Reference in New Issue View Git Blame Copy Permalink