llvm/clang/lib/AST/MicrosoftCXXABI.cpp

//===------- MicrosoftCXXABI.cpp - AST support for the Microsoft C++ ABI --===//
//
// 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 provides C++ AST support targeting the Microsoft Visual C++
// ABI.
//
//===----------------------------------------------------------------------===//

#include "CXXABI.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/Attr.h"
#include "clang/AST/CXXInheritance.h"
#include "clang/AST/DeclCXX.h"
#include "clang/AST/Mangle.h"
#include "clang/AST/MangleNumberingContext.h"
#include "clang/AST/RecordLayout.h"
#include "clang/AST/Type.h"
#include "clang/Basic/TargetInfo.h"

usingnamespaceclang;

namespace {

/// Numbers things which need to correspond across multiple TUs.
/// Typically these are things like static locals, lambdas, or blocks.
class MicrosoftNumberingContext : public MangleNumberingContext { … };

class MSHIPNumberingContext : public MicrosoftNumberingContext { … };

class MSSYCLNumberingContext : public MicrosoftNumberingContext { … };

class MicrosoftCXXABI : public CXXABI { … };
}

// getNumBases() seems to only give us the number of direct bases, and not the
// total.  This function tells us if we inherit from anybody that uses MI, or if
// we have a non-primary base class, which uses the multiple inheritance model.
static bool usesMultipleInheritanceModel(const CXXRecordDecl *RD) { … }

MSInheritanceModel CXXRecordDecl::calculateInheritanceModel() const { … }

MSInheritanceModel CXXRecordDecl::getMSInheritanceModel() const { … }

bool CXXRecordDecl::nullFieldOffsetIsZero() const { … }

MSVtorDispMode CXXRecordDecl::getMSVtorDispMode() const { … }

// Returns the number of pointer and integer slots used to represent a member
// pointer in the MS C++ ABI.
//
// Member function pointers have the following general form;  however, fields
// are dropped as permitted (under the MSVC interpretation) by the inheritance
// model of the actual class.
//
//   struct {
//     // A pointer to the member function to call.  If the member function is
//     // virtual, this will be a thunk that forwards to the appropriate vftable
//     // slot.
//     void *FunctionPointerOrVirtualThunk;
//
//     // An offset to add to the address of the vbtable pointer after
//     // (possibly) selecting the virtual base but before resolving and calling
//     // the function.
//     // Only needed if the class has any virtual bases or bases at a non-zero
//     // offset.
//     int NonVirtualBaseAdjustment;
//
//     // The offset of the vb-table pointer within the object.  Only needed for
//     // incomplete types.
//     int VBPtrOffset;
//
//     // An offset within the vb-table that selects the virtual base containing
//     // the member.  Loading from this offset produces a new offset that is
//     // added to the address of the vb-table pointer to produce the base.
//     int VirtualBaseAdjustmentOffset;
//   };
static std::pair<unsigned, unsigned>
getMSMemberPointerSlots(const MemberPointerType *MPT) { … }

CXXABI::MemberPointerInfo MicrosoftCXXABI::getMemberPointerInfo(
    const MemberPointerType *MPT) const { … }

CXXABI *clang::CreateMicrosoftCXXABI(ASTContext &Ctx) { … }