Refactoring: Introduce getIrType()

As *the* way to access the IrType associated with a Type via its `ctype`
field. Most importantly, it makes sure all access is redirected to the
*unqualified* type's `ctype`, which allows to get rid of the 'multiple
types' workaround for aggregates in DtoType(). Those were e.g. hit for
`shared struct SpinLock`, where the struct's type includes the `shared`
modifier...

gen/dibuilder.cpp

@@ -761,9 +761,8 @@ DISubroutineType DIBuilder::CreateFunctionType(Type *type) {
 
   // The calling convention has to be recorded to distinguish
   // extern(D) functions from extern(C++) ones.
-  DtoType(t);
-  assert(t->ctype);
-  unsigned CC = t->ctype->getIrFuncTy().reverseParams ? DW_CC_D_dmd : 0;
+  unsigned CC =
+      getIrType(t, true)->getIrFuncTy().reverseParams ? DW_CC_D_dmd : 0;
 
   return DBuilder.createSubroutineType(paramsArray, DIFlags::FlagZero, CC);
 }

gen/llvmhelpers.cpp

@@ -1806,9 +1806,9 @@ LLValue *DtoIndexAggregate(LLValue *src, AggregateDeclaration *ad,
   // Look up field to index and any offset to apply.
   unsigned fieldIndex;
   unsigned byteOffset;
-  assert(ad->type->ctype->isAggr());
-  static_cast<IrTypeAggr *>(ad->type->ctype)
-      ->getMemberLocation(vd, fieldIndex, byteOffset);
+  auto irTypeAggr = getIrType(ad->type)->isAggr();
+  assert(irTypeAggr);
+  irTypeAggr->getMemberLocation(vd, fieldIndex, byteOffset);
 
   LLValue *val = DtoGEP(src, 0, fieldIndex);
 
@@ -1828,9 +1828,9 @@ LLValue *DtoIndexAggregate(LLValue *src, AggregateDeclaration *ad,
 unsigned getFieldGEPIndex(AggregateDeclaration *ad, VarDeclaration *vd) {
   unsigned fieldIndex;
   unsigned byteOffset;
-  assert(ad->type->ctype->isAggr());
-  static_cast<IrTypeAggr *>(ad->type->ctype)
-      ->getMemberLocation(vd, fieldIndex, byteOffset);
+  auto irTypeAggr = getIrType(ad->type)->isAggr();
+  assert(irTypeAggr);
+  irTypeAggr->getMemberLocation(vd, fieldIndex, byteOffset);
   assert(byteOffset == 0 && "Cannot address field by a simple GEP.");
   return fieldIndex;
 }

gen/runtime.cpp

@@ -258,9 +258,8 @@ struct LazyFunctionDeclarer {
     // the call to DtoType performs many actions such as rewriting the function
     // type and storing it in dty
     auto llfunctype = llvm::cast<llvm::FunctionType>(DtoType(dty));
-    assert(dty->ctype);
-    auto attrs =
-        dty->ctype->getIrFuncTy().getParamAttrs(gABI->passThisBeforeSret(dty));
+    auto attrs = getIrType(dty)->getIrFuncTy().getParamAttrs(
+        gABI->passThisBeforeSret(dty));
     attrs.merge(attributes);
 
     for (auto fname : mangledFunctionNames) {

gen/tocall.cpp

@@ -40,10 +40,7 @@ IrFuncTy &DtoIrTypeFunction(DValue *fnval) {
     }
   }
 
-  Type *type = stripModifiers(fnval->type->toBasetype());
-  DtoType(type);
-  assert(type->ctype);
-  return type->ctype->getIrFuncTy();
+  return getIrType(fnval->type->toBasetype(), true)->getIrFuncTy();
 }
 
 TypeFunction *DtoTypeFunction(DValue *fnval) {

gen/toconstelem.cpp

@@ -289,7 +289,7 @@ public:
               static_cast<TypeClass *>(tb)->sym->isInterfaceDeclaration()) {
         assert(it->isBaseOf(cd, NULL));
 
-        IrTypeClass *typeclass = cd->type->ctype->isClass();
+        IrTypeClass *typeclass = getIrType(cd->type)->isClass();
 
         // find interface impl
         size_t i_index = typeclass->getInterfaceIndex(it);
@@ -565,7 +565,7 @@ public:
       IF_LOG Logger::cout() << "Using existing global: " << *result << '\n';
     } else {
       auto globalVar = new llvm::GlobalVariable(
-          p->module, origClass->type->ctype->isClass()->getMemoryLLType(),
+          p->module, getIrType(origClass->type)->isClass()->getMemoryLLType(),
           false, llvm::GlobalValue::InternalLinkage, nullptr, ".classref");
       p->setStructLiteralConstant(value, globalVar);
 
@@ -615,10 +615,9 @@ public:
       if (InterfaceDeclaration *it = targetClass->isInterfaceDeclaration()) {
         assert(it->isBaseOf(origClass, NULL));
 
-        IrTypeClass *typeclass = origClass->type->ctype->isClass();
-
         // find interface impl
-        size_t i_index = typeclass->getInterfaceIndex(it);
+        size_t i_index =
+            getIrType(origClass->type)->isClass()->getInterfaceIndex(it);
         assert(i_index != ~0UL);
 
         // offset pointer

gen/tollvm.cpp

@@ -124,32 +124,16 @@ LLType *DtoType(Type *t) {
 
   // aggregates
   case Tstruct: {
-    TypeStruct *ts = static_cast<TypeStruct *>(t);
-    if (ts->sym->type->ty == Terror)
+    auto sd = static_cast<TypeStruct *>(t)->sym;
+    if (sd->type->ty == Terror)
       return getOpaqueErrorType();
-    if (ts->sym->type->ctype) {
-      // This should not happen, but the frontend seems to be buggy. Not
-      // sure if this is the best way to handle the situation, but we
-      // certainly don't want to override ts->sym->type->ctype.
-      IF_LOG Logger::cout()
-          << "Struct with multiple Types detected: " << ts->toChars() << " ("
-          << ts->sym->locToChars() << ")" << std::endl;
-      return ts->sym->type->ctype->getLLType();
-    }
-    return IrTypeStruct::get(ts->sym)->getLLType();
+    return IrTypeStruct::get(sd)->getLLType();
   }
   case Tclass: {
-    TypeClass *tc = static_cast<TypeClass *>(t);
-    if (tc->sym->type->ty == Terror)
+    auto cd = static_cast<TypeClass *>(t)->sym;
+    if (cd->type->ty == Terror)
       return getOpaqueErrorType();
-    if (tc->sym->type->ctype) {
-      // See Tstruct case.
-      IF_LOG Logger::cout()
-          << "Class with multiple Types detected: " << tc->toChars() << " ("
-          << tc->sym->locToChars() << ")" << std::endl;
-      return tc->sym->type->ctype->getLLType();
-    }
-    return IrTypeClass::get(tc->sym)->getLLType();
+    return IrTypeClass::get(cd)->getLLType();
   }
 
   // functions
@@ -182,9 +166,8 @@ LLType *DtoType(Type *t) {
   case Taarray:
     return getVoidPtrType();
 
-  case Tvector: {
+  case Tvector:
     return IrTypeVector::get(t)->getLLType();
-  }
 
   default:
     llvm_unreachable("Unknown class of D Type!");

gen/trycatchfinally.cpp

@@ -179,8 +179,7 @@ void TryCatchScope::emitCatchBodies(IRState &irs, llvm::Value *ehPtrSlot) {
         b.push(cpp_ti);
 
         auto wrapperType = llvm::cast<llvm::StructType>(
-            static_cast<IrTypeClass *>(cppTypeInfoPtrType->ctype)
-                ->getMemoryLLType());
+            getIrType(cppTypeInfoPtrType)->isClass()->getMemoryLLType());
         auto wrapperInit = b.get_constant(wrapperType);
 
         ci = defineGlobal(p.cd->loc, irs.module, wrapperMangle, wrapperInit,

ir/iraggr.cpp

@@ -35,7 +35,7 @@ llvm::StructType *IrAggr::getLLStructType() {
     return llStructType;
 
   LLType *llType = DtoType(type);
-  if (auto irClassType = type->ctype->isClass())
+  if (auto irClassType = getIrType(type)->isClass())
     llType = irClassType->getMemoryLLType();
 
   llStructType = llvm::dyn_cast<LLStructType>(llType);
@@ -223,7 +223,7 @@ IrAggr::createInitializerConstant(const VarInitMap &explicitInitializers) {
   }
 
   // build constant
-  const bool isPacked = static_cast<IrTypeAggr *>(type->ctype)->packed;
+  const bool isPacked = getIrType(type)->isAggr()->packed;
   LLStructType *llType =
       isCompatible ? llStructType
                    : LLStructType::get(gIR->context(), types, isPacked);

ir/irclass.cpp

@@ -45,7 +45,7 @@ IrClass::IrClass(ClassDeclaration *cd) : IrAggr(cd) {
   addInterfaceVtbls(cd);
 
   assert(interfacesWithVtbls.size() ==
-             stripModifiers(type)->ctype->isClass()->getNumInterfaceVtbls() &&
+             getIrType(type)->isClass()->getNumInterfaceVtbls() &&
          "inconsistent number of interface vtables in this class");
 }
 
@@ -67,7 +67,7 @@ LLGlobalVariable *IrClass::getVtblSymbol(bool define) {
   if (!vtbl) {
     const auto irMangle = getIRMangledVTableSymbolName(aggrdecl);
 
-    LLType *vtblTy = stripModifiers(type)->ctype->isClass()->getVtblType();
+    LLType *vtblTy = getIrType(type)->isClass()->getVtblType();
 
     vtbl = declareGlobal(aggrdecl->loc, gIR->module, vtblTy, irMangle,
                          /*isConstant=*/true);
@@ -91,9 +91,7 @@ LLGlobalVariable *IrClass::getClassInfoSymbol(bool define) {
     // The type is also ClassInfo for interfaces – the actual TypeInfo for them
     // is a TypeInfo_Interface instance that references __ClassZ in its "base"
     // member.
-    Type *cinfoType = getClassInfoType();
-    DtoType(cinfoType);
-    IrTypeClass *tc = stripModifiers(cinfoType)->ctype->isClass();
+    IrTypeClass *tc = getIrType(getClassInfoType(), true)->isClass();
     assert(tc && "invalid ClassInfo type");
 
     // We need to keep the symbol mutable as the type is not declared as
@@ -152,7 +150,7 @@ LLGlobalVariable *IrClass::getInterfaceArraySymbol() {
 
   ClassDeclaration *cd = aggrdecl->isClassDeclaration();
 
-  size_t n = stripModifiers(type)->ctype->isClass()->getNumInterfaceVtbls();
+  size_t n = getIrType(type)->isClass()->getNumInterfaceVtbls();
   assert(n > 0 && "getting ClassInfo.interfaces storage symbol, but we "
                   "don't implement any interfaces");
 
@@ -657,7 +655,7 @@ LLConstant *IrClass::getInterfaceVtblInit(BaseClass *b,
 
 void IrClass::defineInterfaceVtbls() {
   const size_t n = interfacesWithVtbls.size();
-  assert(n == stripModifiers(type)->ctype->isClass()->getNumInterfaceVtbls() &&
+  assert(n == getIrType(type)->isClass()->getNumInterfaceVtbls() &&
          "inconsistent number of interface vtables in this class");
 
   for (size_t i = 0; i < n; ++i) {
@@ -676,7 +674,7 @@ LLConstant *IrClass::getClassInfoInterfaces() {
   assert(cd);
 
   size_t n = interfacesWithVtbls.size();
-  assert(stripModifiers(type)->ctype->isClass()->getNumInterfaceVtbls() == n &&
+  assert(getIrType(type)->isClass()->getNumInterfaceVtbls() == n &&
          "inconsistent number of interface vtables in this class");
 
   Type *interfacesArrayType = getInterfacesArrayType();
@@ -710,7 +708,7 @@ LLConstant *IrClass::getClassInfoInterfaces() {
 
     IrClass *irinter = getIrAggr(it->sym);
     assert(irinter && "interface has null IrStruct");
-    IrTypeClass *itc = stripModifiers(irinter->type)->ctype->isClass();
+    IrTypeClass *itc = getIrType(irinter->type)->isClass();
     assert(itc && "null interface IrTypeClass");
 
     // classinfo

ir/irstruct.cpp

@@ -26,8 +26,7 @@
 namespace {
 LLStructType* getTypeInfoStructMemType() {
   Type *t = getStructTypeInfoType();
-  DtoType(t);
-  IrTypeClass *tc = t->ctype->isClass();
+  IrTypeClass *tc = getIrType(t, true)->isClass();
   assert(tc && "invalid TypeInfo_Struct type");
 
   return llvm::cast<LLStructType>(tc->getMemoryLLType());

ir/irtype.cpp

@@ -24,7 +24,7 @@
 IrType::IrType(Type *dt, LLType *lt) : dtype(dt), type(lt) {
   assert(dt && "null D Type");
   assert(lt && "null LLVM Type");
-  assert(!dt->ctype && "already has IrType");
+  assert(!getIrType(dt) && "already has IrType");
 }
 
 IrFuncTy &IrType::getIrFuncTy() {
@@ -37,7 +37,7 @@ IrTypeBasic::IrTypeBasic(Type *dt) : IrType(dt, basic2llvm(dt)) {}
 
 IrTypeBasic *IrTypeBasic::get(Type *dt) {
   auto t = new IrTypeBasic(dt);
-  dt->ctype = t;
+  getIrType(dt) = t;
   return t;
 }
 
@@ -136,9 +136,11 @@ llvm::Type *IrTypeBasic::basic2llvm(Type *t) {
 IrTypePointer::IrTypePointer(Type *dt, LLType *lt) : IrType(dt, lt) {}
 
 IrTypePointer *IrTypePointer::get(Type *dt) {
-  assert(!dt->ctype);
   assert((dt->ty == Tpointer || dt->ty == Tnull) && "not pointer/null type");
 
+  auto &ctype = getIrType(dt);
+  assert(!ctype);
+
   LLType *elemType;
   if (dt->ty == Tnull) {
     elemType = llvm::Type::getInt8Ty(getGlobalContext());
@@ -147,13 +149,13 @@ IrTypePointer *IrTypePointer::get(Type *dt) {
 
     // DtoType could have already created the same type, e.g. for
     // dt == Node* in struct Node { Node* n; }.
-    if (dt->ctype) {
-      return dt->ctype->isPointer();
+    if (ctype) {
+      return ctype->isPointer();
     }
   }
 
   auto t = new IrTypePointer(dt, llvm::PointerType::get(elemType, 0));
-  dt->ctype = t;
+  ctype = t;
   return t;
 }
 
@@ -162,20 +164,22 @@ IrTypePointer *IrTypePointer::get(Type *dt) {
 IrTypeSArray::IrTypeSArray(Type *dt, LLType *lt) : IrType(dt, lt) {}
 
 IrTypeSArray *IrTypeSArray::get(Type *dt) {
-  assert(!dt->ctype);
   assert(dt->ty == Tsarray && "not static array type");
 
+  auto &ctype = getIrType(dt);
+  assert(!ctype);
+
   LLType *elemType = DtoMemType(dt->nextOf());
 
   // We might have already built the type during DtoMemType e.g. as part of a
   // forward reference in a struct.
-  if (!dt->ctype) {
+  if (!ctype) {
     TypeSArray *tsa = static_cast<TypeSArray *>(dt);
     uint64_t dim = static_cast<uint64_t>(tsa->dim->toUInteger());
-    dt->ctype = new IrTypeSArray(dt, llvm::ArrayType::get(elemType, dim));
+    ctype = new IrTypeSArray(dt, llvm::ArrayType::get(elemType, dim));
   }
 
-  return dt->ctype->isSArray();
+  return ctype->isSArray();
 }
 
 //////////////////////////////////////////////////////////////////////////////
@@ -183,20 +187,22 @@ IrTypeSArray *IrTypeSArray::get(Type *dt) {
 IrTypeArray::IrTypeArray(Type *dt, LLType *lt) : IrType(dt, lt) {}
 
 IrTypeArray *IrTypeArray::get(Type *dt) {
-  assert(!dt->ctype);
   assert(dt->ty == Tarray && "not dynamic array type");
 
+  auto &ctype = getIrType(dt);
+  assert(!ctype);
+
   LLType *elemType = DtoMemType(dt->nextOf());
 
   // Could have already built the type as part of a struct forward reference,
   // just as for pointers.
-  if (!dt->ctype) {
+  if (!ctype) {
     llvm::Type *types[] = {DtoSize_t(), llvm::PointerType::get(elemType, 0)};
     LLType *at = llvm::StructType::get(getGlobalContext(), types, false);
-    dt->ctype = new IrTypeArray(dt, at);
+    ctype = new IrTypeArray(dt, at);
   }
 
-  return dt->ctype->isArray();
+  return ctype->isArray();
 }
 
 //////////////////////////////////////////////////////////////////////////////
@@ -204,26 +210,40 @@ IrTypeArray *IrTypeArray::get(Type *dt) {
 IrTypeVector::IrTypeVector(Type *dt, llvm::Type *lt) : IrType(dt, lt) {}
 
 IrTypeVector *IrTypeVector::get(Type *dt) {
-  LLType *lt = vector2llvm(dt);
+  TypeVector *tv = dt->isTypeVector();
+  assert(tv && "not vector type");
+
+  auto &ctype = getIrType(dt);
+  assert(!ctype);
+
+  TypeSArray *tsa = tv->basetype->isTypeSArray();
+  assert(tsa);
+  LLType *elemType = DtoMemType(tsa->next);
+
   // Could have already built the type as part of a struct forward reference,
   // just as for pointers and arrays.
-  if (!dt->ctype) {
-    dt->ctype = new IrTypeVector(dt, lt);
-  }
-  return dt->ctype->isVector();
-}
-
-llvm::Type *IrTypeVector::vector2llvm(Type *dt) {
-  assert(dt->ty == Tvector && "not vector type");
-  TypeVector *tv = static_cast<TypeVector *>(dt);
-  assert(tv->basetype->ty == Tsarray);
-  TypeSArray *tsa = static_cast<TypeSArray *>(tv->basetype);
-  uint64_t dim = static_cast<uint64_t>(tsa->dim->toUInteger());
-  LLType *elemType = DtoMemType(tsa->next);
-  return llvm::VectorType::get(elemType, dim
+  if (!ctype) {
+    LLType *lt = llvm::VectorType::get(elemType, tsa->dim->toUInteger()
 #if LDC_LLVM_VER >= 1100
                                                      ,
                                        /*Scalable=*/false
 #endif
     );
+    ctype = new IrTypeVector(dt, lt);
+  }
+
+  return ctype->isVector();
+}
+
+//////////////////////////////////////////////////////////////////////////////
+
+IrType *&getIrType(Type *t, bool create) {
+  t = stripModifiers(t);
+
+  if (create) {
+    DtoType(t);
+    assert(t->ctype);
+  }
+
+  return t->ctype;
 }

ir/irtype.h

@@ -182,6 +182,9 @@ public:
 protected:
   ///
   explicit IrTypeVector(Type *dt, llvm::Type *lt);
-
-  static llvm::Type *vector2llvm(Type *dt);
 };
+
+//////////////////////////////////////////////////////////////////////////////
+
+/// Returns a reference to the IrType* associated with the specified D type.
+IrType *&getIrType(Type *t, bool create = false);

ir/irtypeclass.cpp

@@ -60,12 +60,13 @@ void IrTypeClass::addClassData(AggrTypeBuilder &builder,
 }
 
 IrTypeClass *IrTypeClass::get(ClassDeclaration *cd) {
-  const auto t = new IrTypeClass(cd);
-  cd->type->ctype = t;
-
   IF_LOG Logger::println("Building class type %s @ %s", cd->toPrettyChars(),
                          cd->loc.toChars());
   LOG_SCOPE;
+
+  const auto t = new IrTypeClass(cd);
+  getIrType(cd->type) = t;
+
   IF_LOG Logger::println("Instance size: %u", cd->structsize);
 
   // This class may contain an align declaration. See GitHub #726.

ir/irtypefunction.cpp

@@ -19,20 +19,22 @@ IrTypeFunction::IrTypeFunction(Type *dt, llvm::Type *lt, IrFuncTy irFty_)
     : IrType(dt, lt), irFty(std::move(irFty_)) {}
 
 IrTypeFunction *IrTypeFunction::get(Type *dt) {
-  assert(!dt->ctype);
-  assert(dt->ty == Tfunction);
+  TypeFunction *tf = dt->isTypeFunction();
+  assert(tf);
 
-  TypeFunction *tf = static_cast<TypeFunction *>(dt);
+  auto &ctype = getIrType(tf);
+  assert(!ctype);
 
   IrFuncTy irFty(tf);
   llvm::Type *lt = DtoFunctionType(tf, irFty, nullptr, nullptr);
 
   // Could have already built the type as part of a struct forward reference,
   // just as for pointers and arrays.
-  if (!dt->ctype) {
-    dt->ctype = new IrTypeFunction(dt, lt, irFty);
+  if (!ctype) {
+    ctype = new IrTypeFunction(dt, lt, irFty);
   }
-  return dt->ctype->isFunction();
+
+  return ctype->isFunction();
 }
 
 //////////////////////////////////////////////////////////////////////////////
@@ -41,11 +43,12 @@ IrTypeDelegate::IrTypeDelegate(Type *dt, llvm::Type *lt, IrFuncTy irFty_)
     : IrType(dt, lt), irFty(std::move(irFty_)) {}
 
 IrTypeDelegate *IrTypeDelegate::get(Type *t) {
-  assert(!t->ctype);
   assert(t->ty == Tdelegate);
-  assert(t->nextOf()->ty == Tfunction);
+  TypeFunction *tf = t->nextOf()->isTypeFunction();
+  assert(tf);
 
-  TypeFunction *tf = static_cast<TypeFunction *>(t->nextOf());
+  auto &ctype = getIrType(t);
+  assert(!ctype);
 
   IrFuncTy irFty(tf);
   llvm::Type *ltf =
@@ -55,8 +58,9 @@ IrTypeDelegate *IrTypeDelegate::get(Type *t) {
 
   // Could have already built the type as part of a struct forward reference,
   // just as for pointers and arrays.
-  if (!t->ctype) {
-    t->ctype = new IrTypeDelegate(t, lt, irFty);
+  if (!ctype) {
+    ctype = new IrTypeDelegate(t, lt, irFty);
   }
-  return t->ctype->isDelegate();
+
+  return ctype->isDelegate();
 }

ir/irtypestruct.cpp

@@ -30,14 +30,15 @@ IrTypeStruct::IrTypeStruct(StructDeclaration *sd)
 
 //////////////////////////////////////////////////////////////////////////////
 
-std::vector<IrTypeStruct*> IrTypeStruct::dcomputeTypes;
+std::vector<IrTypeStruct *> IrTypeStruct::dcomputeTypes;
 
 /// Resets special DCompute structs so they get re-created
 /// with the proper address space when generating device code.
 void IrTypeStruct::resetDComputeTypes() {
-  for(auto&& irTypeStruct : dcomputeTypes) {
-    delete irTypeStruct->dtype->ctype;
-    irTypeStruct->dtype->ctype = nullptr;
+  for (auto irTypeStruct : dcomputeTypes) {
+    auto &ctype = getIrType(irTypeStruct->dtype);
+    delete ctype;
+    ctype = nullptr;
   }
 
   dcomputeTypes.clear();
@@ -46,13 +47,13 @@ void IrTypeStruct::resetDComputeTypes() {
 //////////////////////////////////////////////////////////////////////////////
 
 IrTypeStruct *IrTypeStruct::get(StructDeclaration *sd) {
-  auto t = new IrTypeStruct(sd);
-  sd->type->ctype = t;
-
   IF_LOG Logger::println("Building struct type %s @ %s", sd->toPrettyChars(),
                          sd->loc.toChars());
   LOG_SCOPE;
 
+  auto t = new IrTypeStruct(sd);
+  getIrType(sd->type) = t;
+
   // if it's a forward declaration, all bets are off, stick with the opaque
   if (sd->sizeok != SIZEOKdone) {
     return t;