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-rw-r--r--lib/CodeGen/CGCXX.cpp306
1 files changed, 0 insertions, 306 deletions
diff --git a/lib/CodeGen/CGCXX.cpp b/lib/CodeGen/CGCXX.cpp
deleted file mode 100644
index 7e5fe0fd6b1d5..0000000000000
--- a/lib/CodeGen/CGCXX.cpp
+++ /dev/null
@@ -1,306 +0,0 @@
-//===--- CGCXX.cpp - Emit LLVM Code for declarations ----------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-//
-// This contains code dealing with C++ code generation.
-//
-//===----------------------------------------------------------------------===//
-
-// We might split this into multiple files if it gets too unwieldy
-
-#include "CodeGenModule.h"
-#include "CGCXXABI.h"
-#include "CodeGenFunction.h"
-#include "clang/AST/ASTContext.h"
-#include "clang/AST/Decl.h"
-#include "clang/AST/DeclCXX.h"
-#include "clang/AST/DeclObjC.h"
-#include "clang/AST/Mangle.h"
-#include "clang/AST/RecordLayout.h"
-#include "clang/AST/StmtCXX.h"
-#include "clang/Basic/CodeGenOptions.h"
-#include "llvm/ADT/StringExtras.h"
-using namespace clang;
-using namespace CodeGen;
-
-
-/// Try to emit a base destructor as an alias to its primary
-/// base-class destructor.
-bool CodeGenModule::TryEmitBaseDestructorAsAlias(const CXXDestructorDecl *D) {
- if (!getCodeGenOpts().CXXCtorDtorAliases)
- return true;
-
- // Producing an alias to a base class ctor/dtor can degrade debug quality
- // as the debugger cannot tell them apart.
- if (getCodeGenOpts().OptimizationLevel == 0)
- return true;
-
- // If sanitizing memory to check for use-after-dtor, do not emit as
- // an alias, unless this class owns no members.
- if (getCodeGenOpts().SanitizeMemoryUseAfterDtor &&
- !D->getParent()->field_empty())
- return true;
-
- // If the destructor doesn't have a trivial body, we have to emit it
- // separately.
- if (!D->hasTrivialBody())
- return true;
-
- const CXXRecordDecl *Class = D->getParent();
-
- // We are going to instrument this destructor, so give up even if it is
- // currently empty.
- if (Class->mayInsertExtraPadding())
- return true;
-
- // If we need to manipulate a VTT parameter, give up.
- if (Class->getNumVBases()) {
- // Extra Credit: passing extra parameters is perfectly safe
- // in many calling conventions, so only bail out if the ctor's
- // calling convention is nonstandard.
- return true;
- }
-
- // If any field has a non-trivial destructor, we have to emit the
- // destructor separately.
- for (const auto *I : Class->fields())
- if (I->getType().isDestructedType())
- return true;
-
- // Try to find a unique base class with a non-trivial destructor.
- const CXXRecordDecl *UniqueBase = nullptr;
- for (const auto &I : Class->bases()) {
-
- // We're in the base destructor, so skip virtual bases.
- if (I.isVirtual()) continue;
-
- // Skip base classes with trivial destructors.
- const auto *Base =
- cast<CXXRecordDecl>(I.getType()->castAs<RecordType>()->getDecl());
- if (Base->hasTrivialDestructor()) continue;
-
- // If we've already found a base class with a non-trivial
- // destructor, give up.
- if (UniqueBase) return true;
- UniqueBase = Base;
- }
-
- // If we didn't find any bases with a non-trivial destructor, then
- // the base destructor is actually effectively trivial, which can
- // happen if it was needlessly user-defined or if there are virtual
- // bases with non-trivial destructors.
- if (!UniqueBase)
- return true;
-
- // If the base is at a non-zero offset, give up.
- const ASTRecordLayout &ClassLayout = Context.getASTRecordLayout(Class);
- if (!ClassLayout.getBaseClassOffset(UniqueBase).isZero())
- return true;
-
- // Give up if the calling conventions don't match. We could update the call,
- // but it is probably not worth it.
- const CXXDestructorDecl *BaseD = UniqueBase->getDestructor();
- if (BaseD->getType()->castAs<FunctionType>()->getCallConv() !=
- D->getType()->castAs<FunctionType>()->getCallConv())
- return true;
-
- GlobalDecl AliasDecl(D, Dtor_Base);
- GlobalDecl TargetDecl(BaseD, Dtor_Base);
-
- // The alias will use the linkage of the referent. If we can't
- // support aliases with that linkage, fail.
- llvm::GlobalValue::LinkageTypes Linkage = getFunctionLinkage(AliasDecl);
-
- // We can't use an alias if the linkage is not valid for one.
- if (!llvm::GlobalAlias::isValidLinkage(Linkage))
- return true;
-
- llvm::GlobalValue::LinkageTypes TargetLinkage =
- getFunctionLinkage(TargetDecl);
-
- // Check if we have it already.
- StringRef MangledName = getMangledName(AliasDecl);
- llvm::GlobalValue *Entry = GetGlobalValue(MangledName);
- if (Entry && !Entry->isDeclaration())
- return false;
- if (Replacements.count(MangledName))
- return false;
-
- // Derive the type for the alias.
- llvm::Type *AliasValueType = getTypes().GetFunctionType(AliasDecl);
- llvm::PointerType *AliasType = AliasValueType->getPointerTo();
-
- // Find the referent. Some aliases might require a bitcast, in
- // which case the caller is responsible for ensuring the soundness
- // of these semantics.
- auto *Ref = cast<llvm::GlobalValue>(GetAddrOfGlobal(TargetDecl));
- llvm::Constant *Aliasee = Ref;
- if (Ref->getType() != AliasType)
- Aliasee = llvm::ConstantExpr::getBitCast(Ref, AliasType);
-
- // Instead of creating as alias to a linkonce_odr, replace all of the uses
- // of the aliasee.
- if (llvm::GlobalValue::isDiscardableIfUnused(Linkage) &&
- !(TargetLinkage == llvm::GlobalValue::AvailableExternallyLinkage &&
- TargetDecl.getDecl()->hasAttr<AlwaysInlineAttr>())) {
- // FIXME: An extern template instantiation will create functions with
- // linkage "AvailableExternally". In libc++, some classes also define
- // members with attribute "AlwaysInline" and expect no reference to
- // be generated. It is desirable to reenable this optimisation after
- // corresponding LLVM changes.
- addReplacement(MangledName, Aliasee);
- return false;
- }
-
- // If we have a weak, non-discardable alias (weak, weak_odr), like an extern
- // template instantiation or a dllexported class, avoid forming it on COFF.
- // A COFF weak external alias cannot satisfy a normal undefined symbol
- // reference from another TU. The other TU must also mark the referenced
- // symbol as weak, which we cannot rely on.
- if (llvm::GlobalValue::isWeakForLinker(Linkage) &&
- getTriple().isOSBinFormatCOFF()) {
- return true;
- }
-
- // If we don't have a definition for the destructor yet or the definition is
- // avaialable_externally, don't emit an alias. We can't emit aliases to
- // declarations; that's just not how aliases work.
- if (Ref->isDeclarationForLinker())
- return true;
-
- // Don't create an alias to a linker weak symbol. This avoids producing
- // different COMDATs in different TUs. Another option would be to
- // output the alias both for weak_odr and linkonce_odr, but that
- // requires explicit comdat support in the IL.
- if (llvm::GlobalValue::isWeakForLinker(TargetLinkage))
- return true;
-
- // Create the alias with no name.
- auto *Alias = llvm::GlobalAlias::create(AliasValueType, 0, Linkage, "",
- Aliasee, &getModule());
-
- // Destructors are always unnamed_addr.
- Alias->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global);
-
- // Switch any previous uses to the alias.
- if (Entry) {
- assert(Entry->getType() == AliasType &&
- "declaration exists with different type");
- Alias->takeName(Entry);
- Entry->replaceAllUsesWith(Alias);
- Entry->eraseFromParent();
- } else {
- Alias->setName(MangledName);
- }
-
- // Finally, set up the alias with its proper name and attributes.
- SetCommonAttributes(AliasDecl, Alias);
-
- return false;
-}
-
-llvm::Function *CodeGenModule::codegenCXXStructor(GlobalDecl GD) {
- const CGFunctionInfo &FnInfo = getTypes().arrangeCXXStructorDeclaration(GD);
- auto *Fn = cast<llvm::Function>(
- getAddrOfCXXStructor(GD, &FnInfo, /*FnType=*/nullptr,
- /*DontDefer=*/true, ForDefinition));
-
- setFunctionLinkage(GD, Fn);
-
- CodeGenFunction(*this).GenerateCode(GD, Fn, FnInfo);
- setNonAliasAttributes(GD, Fn);
- SetLLVMFunctionAttributesForDefinition(cast<CXXMethodDecl>(GD.getDecl()), Fn);
- return Fn;
-}
-
-llvm::FunctionCallee CodeGenModule::getAddrAndTypeOfCXXStructor(
- GlobalDecl GD, const CGFunctionInfo *FnInfo, llvm::FunctionType *FnType,
- bool DontDefer, ForDefinition_t IsForDefinition) {
- auto *MD = cast<CXXMethodDecl>(GD.getDecl());
-
- if (isa<CXXDestructorDecl>(MD)) {
- // Always alias equivalent complete destructors to base destructors in the
- // MS ABI.
- if (getTarget().getCXXABI().isMicrosoft() &&
- GD.getDtorType() == Dtor_Complete &&
- MD->getParent()->getNumVBases() == 0)
- GD = GD.getWithDtorType(Dtor_Base);
- }
-
- if (!FnType) {
- if (!FnInfo)
- FnInfo = &getTypes().arrangeCXXStructorDeclaration(GD);
- FnType = getTypes().GetFunctionType(*FnInfo);
- }
-
- llvm::Constant *Ptr = GetOrCreateLLVMFunction(
- getMangledName(GD), FnType, GD, /*ForVTable=*/false, DontDefer,
- /*IsThunk=*/false, /*ExtraAttrs=*/llvm::AttributeList(), IsForDefinition);
- return {FnType, Ptr};
-}
-
-static CGCallee BuildAppleKextVirtualCall(CodeGenFunction &CGF,
- GlobalDecl GD,
- llvm::Type *Ty,
- const CXXRecordDecl *RD) {
- assert(!CGF.CGM.getTarget().getCXXABI().isMicrosoft() &&
- "No kext in Microsoft ABI");
- CodeGenModule &CGM = CGF.CGM;
- llvm::Value *VTable = CGM.getCXXABI().getAddrOfVTable(RD, CharUnits());
- Ty = Ty->getPointerTo()->getPointerTo();
- VTable = CGF.Builder.CreateBitCast(VTable, Ty);
- assert(VTable && "BuildVirtualCall = kext vtbl pointer is null");
- uint64_t VTableIndex = CGM.getItaniumVTableContext().getMethodVTableIndex(GD);
- const VTableLayout &VTLayout = CGM.getItaniumVTableContext().getVTableLayout(RD);
- VTableLayout::AddressPointLocation AddressPoint =
- VTLayout.getAddressPoint(BaseSubobject(RD, CharUnits::Zero()));
- VTableIndex += VTLayout.getVTableOffset(AddressPoint.VTableIndex) +
- AddressPoint.AddressPointIndex;
- llvm::Value *VFuncPtr =
- CGF.Builder.CreateConstInBoundsGEP1_64(VTable, VTableIndex, "vfnkxt");
- llvm::Value *VFunc =
- CGF.Builder.CreateAlignedLoad(VFuncPtr, CGF.PointerAlignInBytes);
- CGCallee Callee(GD, VFunc);
- return Callee;
-}
-
-/// BuildAppleKextVirtualCall - This routine is to support gcc's kext ABI making
-/// indirect call to virtual functions. It makes the call through indexing
-/// into the vtable.
-CGCallee
-CodeGenFunction::BuildAppleKextVirtualCall(const CXXMethodDecl *MD,
- NestedNameSpecifier *Qual,
- llvm::Type *Ty) {
- assert((Qual->getKind() == NestedNameSpecifier::TypeSpec) &&
- "BuildAppleKextVirtualCall - bad Qual kind");
-
- const Type *QTy = Qual->getAsType();
- QualType T = QualType(QTy, 0);
- const RecordType *RT = T->getAs<RecordType>();
- assert(RT && "BuildAppleKextVirtualCall - Qual type must be record");
- const auto *RD = cast<CXXRecordDecl>(RT->getDecl());
-
- if (const auto *DD = dyn_cast<CXXDestructorDecl>(MD))
- return BuildAppleKextVirtualDestructorCall(DD, Dtor_Complete, RD);
-
- return ::BuildAppleKextVirtualCall(*this, MD, Ty, RD);
-}
-
-/// BuildVirtualCall - This routine makes indirect vtable call for
-/// call to virtual destructors. It returns 0 if it could not do it.
-CGCallee
-CodeGenFunction::BuildAppleKextVirtualDestructorCall(
- const CXXDestructorDecl *DD,
- CXXDtorType Type,
- const CXXRecordDecl *RD) {
- assert(DD->isVirtual() && Type != Dtor_Base);
- // Compute the function type we're calling.
- const CGFunctionInfo &FInfo = CGM.getTypes().arrangeCXXStructorDeclaration(
- GlobalDecl(DD, Dtor_Complete));
- llvm::Type *Ty = CGM.getTypes().GetFunctionType(FInfo);
- return ::BuildAppleKextVirtualCall(*this, GlobalDecl(DD, Type), Ty, RD);
-}
generated by cgit v1.2.3 (git 2.25.1) at 2025-11-04 02:30:28 +0000