99 lines · cpp
1//===----------------------------------------------------------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8//9// This provides an abstract class for C++ code generation. Concrete subclasses10// of this implement code generation for specific C++ ABIs.11//12//===----------------------------------------------------------------------===//13 14#include "CIRGenCXXABI.h"15#include "CIRGenFunction.h"16 17#include "clang/AST/Decl.h"18#include "clang/AST/ExprCXX.h"19#include "clang/AST/GlobalDecl.h"20 21using namespace clang;22using namespace clang::CIRGen;23 24CIRGenCXXABI::~CIRGenCXXABI() {}25 26CIRGenCXXABI::AddedStructorArgCounts CIRGenCXXABI::addImplicitConstructorArgs(27 CIRGenFunction &cgf, const CXXConstructorDecl *d, CXXCtorType type,28 bool forVirtualBase, bool delegating, CallArgList &args) {29 AddedStructorArgs addedArgs =30 getImplicitConstructorArgs(cgf, d, type, forVirtualBase, delegating);31 for (auto [idx, prefixArg] : llvm::enumerate(addedArgs.prefix))32 args.insert(args.begin() + 1 + idx,33 CallArg(RValue::get(prefixArg.value), prefixArg.type));34 for (const auto &arg : addedArgs.suffix)35 args.add(RValue::get(arg.value), arg.type);36 return AddedStructorArgCounts(addedArgs.prefix.size(),37 addedArgs.suffix.size());38}39 40CatchTypeInfo CIRGenCXXABI::getCatchAllTypeInfo() {41 return CatchTypeInfo{{}, 0};42}43 44void CIRGenCXXABI::buildThisParam(CIRGenFunction &cgf,45 FunctionArgList ¶ms) {46 const auto *md = cast<CXXMethodDecl>(cgf.curGD.getDecl());47 48 // FIXME: I'm not entirely sure I like using a fake decl just for code49 // generation. Maybe we can come up with a better way?50 auto *thisDecl =51 ImplicitParamDecl::Create(cgm.getASTContext(), nullptr, md->getLocation(),52 &cgm.getASTContext().Idents.get("this"),53 md->getThisType(), ImplicitParamKind::CXXThis);54 params.push_back(thisDecl);55 cgf.cxxabiThisDecl = thisDecl;56 57 // Classic codegen computes the alignment of thisDecl and saves it in58 // CodeGenFunction::CXXABIThisAlignment, but it is only used in emitTypeCheck59 // in CodeGenFunction::StartFunction().60 assert(!cir::MissingFeatures::cxxabiThisAlignment());61}62 63cir::GlobalLinkageKind CIRGenCXXABI::getCXXDestructorLinkage(64 GVALinkage linkage, const CXXDestructorDecl *dtor, CXXDtorType dt) const {65 // Delegate back to cgm by default.66 return cgm.getCIRLinkageForDeclarator(dtor, linkage,67 /*isConstantVariable=*/false);68}69 70mlir::Value CIRGenCXXABI::loadIncomingCXXThis(CIRGenFunction &cgf) {71 ImplicitParamDecl *vd = getThisDecl(cgf);72 Address addr = cgf.getAddrOfLocalVar(vd);73 return cir::LoadOp::create(cgf.getBuilder(), cgf.getLoc(vd->getLocation()),74 addr.getElementType(), addr.getPointer());75}76 77void CIRGenCXXABI::setCXXABIThisValue(CIRGenFunction &cgf,78 mlir::Value thisPtr) {79 /// Initialize the 'this' slot.80 assert(getThisDecl(cgf) && "no 'this' variable for function");81 cgf.cxxabiThisValue = thisPtr;82}83 84CharUnits CIRGenCXXABI::getArrayCookieSize(const CXXNewExpr *e) {85 if (!requiresArrayCookie(e))86 return CharUnits::Zero();87 88 return getArrayCookieSizeImpl(e->getAllocatedType());89}90 91bool CIRGenCXXABI::requiresArrayCookie(const CXXNewExpr *e) {92 // If the class's usual deallocation function takes two arguments,93 // it needs a cookie.94 if (e->doesUsualArrayDeleteWantSize())95 return true;96 97 return e->getAllocatedType().isDestructedType();98}99