void DtoResolveStruct(StructDeclaration* sd) { // Make sure to resolve each struct type exactly once. if (sd->ir.resolved) return; sd->ir.resolved = true; Logger::println("Resolving struct type: %s (%s)", sd->toChars(), sd->loc.toChars()); LOG_SCOPE; // make sure type exists DtoType(sd->type); // if it's a forward declaration, all bets are off. The type should be enough if (sd->sizeok != 1) return; // create the IrAggr IrAggr* irstruct = new IrAggr(sd); sd->ir.irStruct = irstruct; // Set up our field metadata. for (ArrayIter<VarDeclaration> it(sd->fields); !it.done(); it.next()) { VarDeclaration* vd = it.get(); assert(!vd->ir.irField); (void)new IrField(vd); } // perform definition bool emitGlobalData = mustDefineSymbol(sd); if (emitGlobalData) { // emit the initZ symbol LLGlobalVariable* initZ = irstruct->getInitSymbol(); // set initZ initializer initZ->setInitializer(irstruct->getDefaultInit()); } // emit members if (sd->members) { for (ArrayIter<Dsymbol> it(sd->members); !it.done(); it.next()) { it.get()->codegen(Type::sir); } } if (emitGlobalData) { // emit typeinfo DtoTypeInfoOf(sd->type); } }
void visit(StructDeclaration *decl) override { IF_LOG Logger::println("StructDeclaration::codegen: '%s'", decl->toPrettyChars()); LOG_SCOPE if (decl->ir->isDefined()) { return; } if (decl->type->ty == Terror) { error(decl->loc, "had semantic errors when compiling"); decl->ir->setDefined(); return; } if (!(decl->members && decl->symtab)) { return; } DtoResolveStruct(decl); decl->ir->setDefined(); for (auto m : *decl->members) { m->accept(this); } // Skip __initZ and typeinfo for @compute device code. // TODO: support global variables and thus __initZ if (!irs->dcomputetarget) { // Define the __initZ symbol. IrAggr *ir = getIrAggr(decl); auto &initZ = ir->getInitSymbol(); auto initGlobal = llvm::cast<LLGlobalVariable>(initZ); initZ = irs->setGlobalVarInitializer(initGlobal, ir->getDefaultInit()); setLinkage(decl, initGlobal); // emit typeinfo DtoTypeInfoOf(decl->type, /*base=*/false); } // Emit __xopEquals/__xopCmp/__xtoHash. if (decl->xeq && decl->xeq != decl->xerreq) { decl->xeq->accept(this); } if (decl->xcmp && decl->xcmp != decl->xerrcmp) { decl->xcmp->accept(this); } if (decl->xhash) { decl->xhash->accept(this); } }
void DtoResolveClass(ClassDeclaration* cd) { if (cd->ir.isResolved()) return; cd->ir.setResolved(); IF_LOG Logger::println("DtoResolveClass(%s): %s", cd->toPrettyChars(), cd->loc.toChars()); LOG_SCOPE; // make sure the base classes are processed first for (BaseClasses::iterator I = cd->baseclasses->begin(), E = cd->baseclasses->end(); I != E; ++I) { DtoResolveClass((*I)->base); } // make sure type exists DtoType(cd->type); // create IrAggr IrAggr* irAggr = getIrAggr(cd, true); // make sure all fields really get their ir field for (VarDeclarations::iterator I = cd->fields.begin(), E = cd->fields.end(); I != E; ++I) { VarDeclaration* vd = *I; IF_LOG { if (isIrFieldCreated(vd)) Logger::println("class field already exists"); } getIrField(vd, true); } // emit the interfaceInfosZ symbol if necessary if (cd->vtblInterfaces && cd->vtblInterfaces->dim > 0) irAggr->getInterfaceArraySymbol(); // initializer is applied when it's built // interface only emit typeinfo and classinfo if (cd->isInterfaceDeclaration()) { irAggr->initializeInterface(); } }
void DtoResolveClass(ClassDeclaration *cd) { if (cd->ir->isResolved()) { return; } cd->ir->setResolved(); IF_LOG Logger::println("DtoResolveClass(%s): %s", cd->toPrettyChars(), cd->loc.toChars()); LOG_SCOPE; // make sure the base classes are processed first for (auto bc : *cd->baseclasses) { DtoResolveClass(bc->sym); } // make sure type exists DtoType(cd->type); // create IrAggr IrAggr *irAggr = getIrAggr(cd, true); // make sure all fields really get their ir field for (auto vd : cd->fields) { IF_LOG { if (isIrFieldCreated(vd)) { Logger::println("class field already exists"); } } getIrField(vd, true); } // emit the interfaceInfosZ symbol if necessary if (cd->vtblInterfaces && cd->vtblInterfaces->dim > 0) { irAggr->getInterfaceArraySymbol(); // initializer is applied when it's built } // interface only emit typeinfo and classinfo if (cd->isInterfaceDeclaration()) { irAggr->initializeInterface(); } }
void visit(InterfaceDeclaration *decl) override { IF_LOG Logger::println("InterfaceDeclaration::codegen: '%s'", decl->toPrettyChars()); LOG_SCOPE assert(!irs->dcomputetarget); if (decl->ir->isDefined()) { return; } if (decl->type->ty == Terror) { error(decl->loc, "had semantic errors when compiling"); decl->ir->setDefined(); return; } if (decl->members && decl->symtab) { DtoResolveClass(decl); decl->ir->setDefined(); // Emit any members (e.g. final functions). for (auto m : *decl->members) { m->accept(this); } // Emit TypeInfo. DtoTypeInfoOf(decl->type, /*base=*/false); // Declare __InterfaceZ. IrAggr *ir = getIrAggr(decl); llvm::GlobalVariable *interfaceZ = ir->getClassInfoSymbol(); // Only define if not speculative. if (!isSpeculativeType(decl->type)) { interfaceZ->setInitializer(ir->getClassInfoInit()); setLinkage(decl, interfaceZ); } } }
void visit(ClassDeclaration *decl) override { IF_LOG Logger::println("ClassDeclaration::codegen: '%s'", decl->toPrettyChars()); LOG_SCOPE assert(!irs->dcomputetarget); if (decl->ir->isDefined()) { return; } if (decl->type->ty == Terror) { error(decl->loc, "had semantic errors when compiling"); decl->ir->setDefined(); return; } if (decl->members && decl->symtab) { DtoResolveClass(decl); decl->ir->setDefined(); for (auto m : *decl->members) { m->accept(this); } IrAggr *ir = getIrAggr(decl); const auto lwc = DtoLinkage(decl); auto &initZ = ir->getInitSymbol(); auto initGlobal = llvm::cast<LLGlobalVariable>(initZ); initZ = irs->setGlobalVarInitializer(initGlobal, ir->getDefaultInit()); setLinkage(lwc, initGlobal); llvm::GlobalVariable *vtbl = ir->getVtblSymbol(); vtbl->setInitializer(ir->getVtblInit()); setLinkage(lwc, vtbl); llvm::GlobalVariable *classZ = ir->getClassInfoSymbol(); if (!isSpeculativeType(decl->type)) { classZ->setInitializer(ir->getClassInfoInit()); setLinkage(lwc, classZ); } } }
void visit(TypeInfoStructDeclaration *decl) override { IF_LOG Logger::println("TypeInfoStructDeclaration::llvmDefine() %s", decl->toChars()); LOG_SCOPE; // make sure struct is resolved assert(decl->tinfo->ty == Tstruct); TypeStruct *tc = static_cast<TypeStruct *>(decl->tinfo); StructDeclaration *sd = tc->sym; // check declaration in object.d const auto structTypeInfoType = getStructTypeInfoType(); const auto structTypeInfoDecl = Type::typeinfostruct; // On x86_64, class TypeInfo_Struct contains 2 additional fields // (m_arg1/m_arg2) which are used for the X86_64 System V ABI varargs // implementation. They are not present on any other cpu/os. const bool isX86_64 = global.params.targetTriple->getArch() == llvm::Triple::x86_64; const unsigned expectedFields = 11 + (isX86_64 ? 2 : 0); const unsigned actualFields = structTypeInfoDecl->fields.dim - 1; // union of xdtor/xdtorti counts as 2 overlapping fields if (actualFields != expectedFields) { error(Loc(), "Unexpected number of `object.TypeInfo_Struct` fields; " "druntime version does not match compiler"); fatal(); } RTTIBuilder b(structTypeInfoType); // handle opaque structs if (!sd->members) { Logger::println("is opaque struct, emitting dummy TypeInfo_Struct"); b.push_null_void_array(); // name b.push_null_void_array(); // m_init b.push_null_vp(); // xtoHash b.push_null_vp(); // xopEquals b.push_null_vp(); // xopCmp b.push_null_vp(); // xtoString b.push_uint(0); // m_flags b.push_null_vp(); // xdtor/xdtorti b.push_null_vp(); // xpostblit b.push_uint(0); // m_align if (isX86_64) { b.push_null_vp(); // m_arg1 b.push_null_vp(); // m_arg2 } b.push_null_vp(); // m_RTInfo b.finalize(gvar); return; } // can't emit typeinfo for forward declarations if (sd->sizeok != SIZEOKdone) { sd->error("cannot emit `TypeInfo` for forward declaration"); fatal(); } DtoResolveStruct(sd); if (TemplateInstance *ti = sd->isInstantiated()) { if (!ti->needsCodegen()) { assert(ti->minst || sd->requestTypeInfo); // We won't emit ti, so emit the special member functions in here. if (sd->xeq && sd->xeq != StructDeclaration::xerreq && sd->xeq->semanticRun >= PASSsemantic3) { Declaration_codegen(sd->xeq); } if (sd->xcmp && sd->xcmp != StructDeclaration::xerrcmp && sd->xcmp->semanticRun >= PASSsemantic3) { Declaration_codegen(sd->xcmp); } if (FuncDeclaration *ftostr = search_toString(sd)) { if (ftostr->semanticRun >= PASSsemantic3) Declaration_codegen(ftostr); } if (sd->xhash && sd->xhash->semanticRun >= PASSsemantic3) { Declaration_codegen(sd->xhash); } if (sd->postblit && sd->postblit->semanticRun >= PASSsemantic3) { Declaration_codegen(sd->postblit); } if (sd->dtor && sd->dtor->semanticRun >= PASSsemantic3) { Declaration_codegen(sd->dtor); } if (sd->tidtor && sd->tidtor->semanticRun >= PASSsemantic3) { Declaration_codegen(sd->tidtor); } } } IrAggr *iraggr = getIrAggr(sd); // string name b.push_string(sd->toPrettyChars()); // void[] m_init // The protocol is to write a null pointer for zero-initialized arrays. The // length field is always needed for tsize(). llvm::Constant *initPtr; if (tc->isZeroInit(Loc())) { initPtr = getNullValue(getVoidPtrType()); } else { initPtr = iraggr->getInitSymbol(); } b.push_void_array(getTypeStoreSize(DtoType(tc)), initPtr); // function xtoHash FuncDeclaration *fd = sd->xhash; b.push_funcptr(fd); // function xopEquals fd = sd->xeq; b.push_funcptr(fd); // function xopCmp fd = sd->xcmp; b.push_funcptr(fd); // function xtoString fd = search_toString(sd); b.push_funcptr(fd); // uint m_flags unsigned hasptrs = tc->hasPointers() ? 1 : 0; b.push_uint(hasptrs); // function xdtor/xdtorti b.push_funcptr(sd->tidtor); // function xpostblit FuncDeclaration *xpostblit = sd->postblit; if (xpostblit && sd->postblit->storage_class & STCdisable) { xpostblit = nullptr; } b.push_funcptr(xpostblit); // uint m_align b.push_uint(DtoAlignment(tc)); if (isX86_64) { // TypeInfo m_arg1 // TypeInfo m_arg2 Type *t = sd->arg1type; for (unsigned i = 0; i < 2; i++) { if (t) { t = merge(t); b.push_typeinfo(t); } else { b.push_null(getTypeInfoType()); } t = sd->arg2type; } } // immutable(void)* m_RTInfo // The cases where getRTInfo is null are not quite here, but the code is // modelled after what DMD does. if (sd->getRTInfo) { b.push(toConstElem(sd->getRTInfo, gIR)); } else if (!tc->hasPointers()) { b.push_size_as_vp(0); // no pointers } else { b.push_size_as_vp(1); // has pointers } // finish b.finalize(gvar); }
LLConstant * IrAggr::getClassInfoInterfaces() { IF_LOG Logger::println("Building ClassInfo.interfaces"); LOG_SCOPE; ClassDeclaration* cd = aggrdecl->isClassDeclaration(); assert(cd); size_t n = interfacesWithVtbls.size(); assert(stripModifiers(type)->irtype->isClass()->getNumInterfaceVtbls() == n && "inconsistent number of interface vtables in this class"); VarDeclarationIter interfaces_idx(ClassDeclaration::classinfo->fields, 3); if (n == 0) return getNullValue(DtoType(interfaces_idx->type)); // Build array of: // // struct Interface // { // ClassInfo classinfo; // void*[] vtbl; // ptrdiff_t offset; // } LLSmallVector<LLConstant*, 6> constants; constants.reserve(cd->vtblInterfaces->dim); LLType* classinfo_type = DtoType(ClassDeclaration::classinfo->type); LLType* voidptrptr_type = DtoType( Type::tvoid->pointerTo()->pointerTo()); VarDeclarationIter idx(ClassDeclaration::classinfo->fields, 3); LLStructType* interface_type = isaStruct(DtoType(idx->type->nextOf())); assert(interface_type); for (size_t i = 0; i < n; ++i) { BaseClass* it = interfacesWithVtbls[i]; IF_LOG Logger::println("Adding interface %s", it->base->toPrettyChars()); IrAggr* irinter = it->base->ir.irAggr; assert(irinter && "interface has null IrStruct"); IrTypeClass* itc = stripModifiers(irinter->type)->irtype->isClass(); assert(itc && "null interface IrTypeClass"); // classinfo LLConstant* ci = irinter->getClassInfoSymbol(); ci = DtoBitCast(ci, classinfo_type); // vtbl LLConstant* vtb; // interface get a null if (cd->isInterfaceDeclaration()) { vtb = DtoConstSlice(DtoConstSize_t(0), getNullValue(voidptrptr_type)); } else { ClassGlobalMap::iterator itv = interfaceVtblMap.find(it->base); assert(itv != interfaceVtblMap.end() && "interface vtbl not found"); vtb = itv->second; vtb = DtoBitCast(vtb, voidptrptr_type); vtb = DtoConstSlice(DtoConstSize_t(itc->getVtblSize()), vtb); } // offset LLConstant* off = DtoConstSize_t(it->offset); // create Interface struct LLConstant* inits[3] = { ci, vtb, off }; LLConstant* entry = LLConstantStruct::get(interface_type, llvm::makeArrayRef(inits, 3)); constants.push_back(entry); } // create Interface[N] LLArrayType* array_type = llvm::ArrayType::get(interface_type, n); // create and apply initializer LLConstant* arr = LLConstantArray::get(array_type, constants); classInterfacesArray->setInitializer(arr); // return null, only baseclass provide interfaces if (cd->vtblInterfaces->dim == 0) { return getNullValue(DtoType(interfaces_idx->type)); } // only the interface explicitly implemented by this class // (not super classes) should show in ClassInfo LLConstant* idxs[2] = { DtoConstSize_t(0), DtoConstSize_t(n - cd->vtblInterfaces->dim) }; LLConstant* ptr = llvm::ConstantExpr::getGetElementPtr( classInterfacesArray, idxs, true); // return as a slice return DtoConstSlice( DtoConstSize_t(cd->vtblInterfaces->dim), ptr ); }
LLConstant* DtoDefineClassInfo(ClassDeclaration* cd) { // The layout is: // { // void **vptr; // monitor_t monitor; // byte[] initializer; // static initialization data // char[] name; // class name // void *[] vtbl; // Interface[] interfaces; // ClassInfo *base; // base class // void *destructor; // void *invariant; // class invariant // uint flags; // void *deallocator; // OffsetTypeInfo[] offTi; // void *defaultConstructor; // version(D_Version2) // immutable(void)* m_RTInfo; // else // TypeInfo typeinfo; // since dmd 1.045 // } Logger::println("DtoDefineClassInfo(%s)", cd->toChars()); LOG_SCOPE; assert(cd->type->ty == Tclass); TypeClass* cdty = static_cast<TypeClass*>(cd->type); IrAggr* ir = cd->ir.irAggr; assert(ir); ClassDeclaration* cinfo = ClassDeclaration::classinfo; if (cinfo->fields.dim != 12) { error("object.d ClassInfo class is incorrect"); fatal(); } // use the rtti builder RTTIBuilder b(ClassDeclaration::classinfo); LLConstant* c; LLType* voidPtr = getVoidPtrType(); LLType* voidPtrPtr = getPtrToType(voidPtr); // byte[] init if (cd->isInterfaceDeclaration()) { b.push_null_void_array(); } else { LLType* cd_type = cdty->irtype->isClass()->getMemoryLLType(); size_t initsz = getTypePaddedSize(cd_type); b.push_void_array(initsz, ir->getInitSymbol()); } // class name // code from dmd const char *name = cd->ident->toChars(); size_t namelen = strlen(name); if (!(namelen > 9 && memcmp(name, "TypeInfo_", 9) == 0)) { name = cd->toPrettyChars(); namelen = strlen(name); } b.push_string(name); // vtbl array if (cd->isInterfaceDeclaration()) { b.push_array(0, getNullValue(voidPtrPtr)); } else { c = DtoBitCast(ir->getVtblSymbol(), voidPtrPtr); b.push_array(cd->vtbl.dim, c); } // interfaces array b.push(ir->getClassInfoInterfaces()); // base classinfo // interfaces never get a base , just the interfaces[] if (cd->baseClass && !cd->isInterfaceDeclaration()) b.push_classinfo(cd->baseClass); else b.push_null(cinfo->type); // destructor if (cd->isInterfaceDeclaration()) b.push_null_vp(); else b.push(build_class_dtor(cd)); // invariant VarDeclaration* invVar = static_cast<VarDeclaration*>(cinfo->fields.data[6]); b.push_funcptr(cd->inv, invVar->type); // uint flags unsigned flags; if (cd->isInterfaceDeclaration()) flags = 4 | cd->isCOMinterface() | 32; else flags = build_classinfo_flags(cd); b.push_uint(flags); // deallocator b.push_funcptr(cd->aggDelete, Type::tvoid->pointerTo()); // offset typeinfo VarDeclaration* offTiVar = static_cast<VarDeclaration*>(cinfo->fields.data[9]); #if GENERATE_OFFTI if (cd->isInterfaceDeclaration()) b.push_null(offTiVar->type); else b.push(build_offti_array(cd, DtoType(offTiVar->type))); #else // GENERATE_OFFTI b.push_null(offTiVar->type); #endif // GENERATE_OFFTI // default constructor VarDeclaration* defConstructorVar = static_cast<VarDeclaration*>(cinfo->fields.data[10]); b.push_funcptr(cd->defaultCtor, defConstructorVar->type); // immutable(void)* m_RTInfo; // The cases where getRTInfo is null are not quite here, but the code is // modelled after what DMD does. if (cd->getRTInfo) b.push(cd->getRTInfo->toConstElem(gIR)); else if (flags & 2) b.push_size_as_vp(0); // no pointers else b.push_size_as_vp(1); // has pointers /*size_t n = inits.size(); for (size_t i=0; i<n; ++i) { Logger::cout() << "inits[" << i << "]: " << *inits[i] << '\n'; }*/ // build the initializer LLType *initType = ir->classInfo->getType()->getContainedType(0); LLConstant* finalinit = b.get_constant(isaStruct(initType)); //Logger::cout() << "built the classinfo initializer:\n" << *finalinit <<'\n'; ir->constClassInfo = finalinit; // sanity check assert(finalinit->getType() == initType && "__ClassZ initializer does not match the ClassInfo type"); // return initializer return finalinit; }
void DtoResolveClass(ClassDeclaration* cd) { // make sure the base classes are processed first ArrayIter<BaseClass> base_iter(cd->baseclasses); while (base_iter.more()) { BaseClass* bc = base_iter.get(); if (bc) { bc->base->codegen(Type::sir); } base_iter.next(); } if (cd->ir.resolved) return; cd->ir.resolved = true; Logger::println("DtoResolveClass(%s): %s", cd->toPrettyChars(), cd->loc.toChars()); LOG_SCOPE; // make sure type exists DtoType(cd->type); // create IrAggr assert(cd->ir.irAggr == NULL); IrAggr* irAggr = new IrAggr(cd); cd->ir.irAggr = irAggr; // make sure all fields really get their ir field ArrayIter<VarDeclaration> it(cd->fields); for (; !it.done(); it.next()) { VarDeclaration* vd = it.get(); if (vd->ir.irField == NULL) { new IrField(vd); } else { IF_LOG Logger::println("class field already exists!!!"); } } bool needs_def = mustDefineSymbol(cd); // emit the ClassZ symbol LLGlobalVariable* ClassZ = irAggr->getClassInfoSymbol(); // emit the interfaceInfosZ symbol if necessary if (cd->vtblInterfaces && cd->vtblInterfaces->dim > 0) irAggr->getInterfaceArraySymbol(); // initializer is applied when it's built // interface only emit typeinfo and classinfo if (cd->isInterfaceDeclaration()) { irAggr->initializeInterface(); } else { // emit the initZ symbol LLGlobalVariable* initZ = irAggr->getInitSymbol(); // emit the vtblZ symbol LLGlobalVariable* vtblZ = irAggr->getVtblSymbol(); // perform definition if (needs_def) { // set symbol initializers initZ->setInitializer(irAggr->getDefaultInit()); vtblZ->setInitializer(irAggr->getVtblInit()); } } // emit members if (cd->members) { ArrayIter<Dsymbol> it(*cd->members); while (!it.done()) { Dsymbol* member = it.get(); if (member) member->codegen(Type::sir); it.next(); } } if (needs_def) { // emit typeinfo DtoTypeInfoOf(cd->type); // define classinfo ClassZ->setInitializer(irAggr->getClassInfoInit()); } }
void visit(TypeInfoStructDeclaration *decl) { IF_LOG Logger::println("TypeInfoStructDeclaration::llvmDefine() %s", decl->toChars()); LOG_SCOPE; // make sure struct is resolved assert(decl->tinfo->ty == Tstruct); TypeStruct *tc = static_cast<TypeStruct *>(decl->tinfo); StructDeclaration *sd = tc->sym; // handle opaque structs if (!sd->members) { RTTIBuilder b(Type::typeinfostruct); b.finalize(getIrGlobal(decl)); return; } // can't emit typeinfo for forward declarations if (sd->sizeok != SIZEOKdone) { sd->error("cannot emit TypeInfo for forward declaration"); fatal(); } DtoResolveStruct(sd); IrAggr* iraggr = getIrAggr(sd); RTTIBuilder b(Type::typeinfostruct); // char[] name b.push_string(sd->toPrettyChars()); // void[] init // The protocol is to write a null pointer for zero-initialized arrays. The // length field is always needed for tsize(). llvm::Constant *initPtr; if (tc->isZeroInit(Loc())) initPtr = getNullValue(getVoidPtrType()); else initPtr = iraggr->getInitSymbol(); b.push_void_array(getTypeStoreSize(DtoType(tc)), initPtr); // well use this module for all overload lookups // toHash FuncDeclaration* fd = sd->xhash; b.push_funcptr(fd); // opEquals fd = sd->xeq; b.push_funcptr(fd); // opCmp fd = sd->xcmp; b.push_funcptr(fd); // toString fd = search_toString(sd); b.push_funcptr(fd); // uint m_flags; unsigned hasptrs = tc->hasPointers() ? 1 : 0; b.push_uint(hasptrs); // On x86_64, class TypeInfo_Struct contains 2 additional fields // (m_arg1/m_arg2) which are used for the X86_64 System V ABI varargs // implementation. They are not present on any other cpu/os. assert((global.params.targetTriple.getArch() != llvm::Triple::x86_64 && Type::typeinfostruct->fields.dim == 11) || (global.params.targetTriple.getArch() == llvm::Triple::x86_64 && Type::typeinfostruct->fields.dim == 13)); //void function(void*) xdtor; b.push_funcptr(sd->dtor); //void function(void*) xpostblit; FuncDeclaration *xpostblit = sd->postblit; if (xpostblit && sd->postblit->storage_class & STCdisable) xpostblit = 0; b.push_funcptr(xpostblit); //uint m_align; b.push_uint(tc->alignsize()); if (global.params.is64bit) { // TypeInfo m_arg1; // TypeInfo m_arg2; Type *t = sd->arg1type; for (unsigned i = 0; i < 2; i++) { if (t) { t = t->merge(); b.push_typeinfo(t); } else b.push_null(Type::dtypeinfo->type); t = sd->arg2type; } } // immutable(void)* m_RTInfo; // The cases where getRTInfo is null are not quite here, but the code is // modelled after what DMD does. if (sd->getRTInfo) b.push(toConstElem(sd->getRTInfo, gIR)); else if (!tc->hasPointers()) b.push_size_as_vp(0); // no pointers else b.push_size_as_vp(1); // has pointers // finish b.finalize(getIrGlobal(decl)); }