llvm/clang/lib/AST/ItaniumCXXABI.cpp

//===------- ItaniumCXXABI.cpp - AST support for the Itanium 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 Itanium C++ ABI, which is
// documented at:
//  http://www.codesourcery.com/public/cxx-abi/abi.html
//  http://www.codesourcery.com/public/cxx-abi/abi-eh.html
//
// It also supports the closely-related ARM C++ ABI, documented at:
// http://infocenter.arm.com/help/topic/com.arm.doc.ihi0041c/IHI0041C_cppabi.pdf
//
//===----------------------------------------------------------------------===//

#include "CXXABI.h"
#include "clang/AST/ASTContext.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"
#include "llvm/ADT/FoldingSet.h"
#include "llvm/ADT/iterator.h"
#include <optional>

usingnamespaceclang;

namespace {

/// According to Itanium C++ ABI 5.1.2:
/// the name of an anonymous union is considered to be
/// the name of the first named data member found by a pre-order,
/// depth-first, declaration-order walk of the data members of
/// the anonymous union.
/// If there is no such data member (i.e., if all of the data members
/// in the union are unnamed), then there is no way for a program to
/// refer to the anonymous union, and there is therefore no need to mangle its name.
///
/// Returns the name of anonymous union VarDecl or nullptr if it is not found.
static const IdentifierInfo *findAnonymousUnionVarDeclName(const VarDecl& VD) { … }

/// The name of a decomposition declaration.
struct DecompositionDeclName { … };
}

namespace llvm {
template<typename T> bool isDenseMapKeyEmpty(T V) { … }
template<typename T> bool isDenseMapKeyTombstone(T V) { … }

template <typename T>
std::optional<bool> areDenseMapKeysEqualSpecialValues(T LHS, T RHS) { … }

template<>
struct DenseMapInfo<DecompositionDeclName> { … };
}

namespace {

/// Keeps track of the mangled names of lambda expressions and block
/// literals within a particular context.
class ItaniumNumberingContext : public MangleNumberingContext { … };

// A version of this for SYCL that makes sure that 'device' mangling context
// matches the lambda mangling number, so that __builtin_sycl_unique_stable_name
// can be consistently generated between a MS and Itanium host by just referring
// to the device mangling number.
class ItaniumSYCLNumberingContext : public ItaniumNumberingContext { … };

class ItaniumCXXABI : public CXXABI { … };
}

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

std::unique_ptr<MangleNumberingContext>
clang::createItaniumNumberingContext(MangleContext *Mangler) { … }