static llvm::GlobalValue::LinkageTypes lowerFuncLinkage(FuncDeclaration* fdecl)
{
// Intrinsics are always external.
if (fdecl->llvmInternal == LLVMintrinsic)
return llvm::GlobalValue::ExternalLinkage;
// Generated array op functions behave like templates in that they might be
// emitted into many different modules.
if (fdecl->isArrayOp && !isDruntimeArrayOp(fdecl))
return templateLinkage;
// A body-less declaration always needs to be marked as external in LLVM
// (also e.g. naked template functions which would otherwise be weak_odr,
// but where the definition is in module-level inline asm).
if (!fdecl->fbody || fdecl->naked)
return llvm::GlobalValue::ExternalLinkage;
return DtoLinkage(fdecl);
}
void VarDeclaration::codegen(Ir* p)
{
Logger::print("VarDeclaration::codegen(): %s | %s\n", toChars(), type->toChars());
LOG_SCOPE;
if (type->ty == Terror)
{ error("had semantic errors when compiling");
return;
}
// just forward aliases
if (aliassym)
{
Logger::println("alias sym");
toAlias()->codegen(p);
return;
}
// output the parent aggregate first
if (AggregateDeclaration* ad = isMember())
ad->codegen(p);
// global variable
// taken from dmd2/structs
if (isDataseg() || (storage_class & (STCconst | STCimmutable) && init))
{
Logger::println("data segment");
#if 0 // TODO:
assert(!(storage_class & STCmanifest) &&
"manifest constant being codegen'd!");
#endif
// don't duplicate work
if (this->ir.resolved) return;
this->ir.resolved = true;
this->ir.declared = true;
this->ir.irGlobal = new IrGlobal(this);
Logger::println("parent: %s (%s)", parent->toChars(), parent->kind());
// not sure why this is only needed for d2
bool _isconst = isConst() && init;
Logger::println("Creating global variable");
assert(!ir.initialized);
ir.initialized = gIR->dmodule;
std::string _name(mangle());
LLType *_type = DtoConstInitializerType(type, init);
// create the global variable
#if LDC_LLVM_VER >= 302
// FIXME: clang uses a command line option for the thread model
LLGlobalVariable* gvar = new LLGlobalVariable(*gIR->module, _type, _isconst,
DtoLinkage(this), NULL, _name, 0,
isThreadlocal() ? LLGlobalVariable::GeneralDynamicTLSModel
: LLGlobalVariable::NotThreadLocal);
#else
LLGlobalVariable* gvar = new LLGlobalVariable(*gIR->module, _type, _isconst,
DtoLinkage(this), NULL, _name, 0, isThreadlocal());
#endif
this->ir.irGlobal->value = gvar;
// Set the alignment (it is important not to use type->alignsize because
// VarDeclarations can have an align() attribute independent of the type
// as well).
if (alignment != STRUCTALIGN_DEFAULT)
gvar->setAlignment(alignment);
if (Logger::enabled())
Logger::cout() << *gvar << '\n';
// if this global is used from a nested function, this is necessary or
// optimization could potentially remove the global (if it's the only use)
if (nakedUse)
gIR->usedArray.push_back(DtoBitCast(gvar, getVoidPtrType()));
// assign the initializer
if (!(storage_class & STCextern) && mustDefineSymbol(this))
{
if (Logger::enabled())
{
Logger::println("setting initializer");
Logger::cout() << "global: " << *gvar << '\n';
#if 0
Logger::cout() << "init: " << *initVal << '\n';
#endif
}
// build the initializer
LLConstant *initVal = DtoConstInitializer(loc, type, init);
// set the initializer
assert(!ir.irGlobal->constInit);
ir.irGlobal->constInit = initVal;
gvar->setInitializer(initVal);
// do debug info
DtoDwarfGlobalVariable(gvar, this);
}
}
}
void setLinkage(Dsymbol *sym, llvm::GlobalObject *obj) {
setLinkage(DtoLinkage(sym), obj);
}
llvm::GlobalVariable * IrAggr::getInterfaceVtbl(BaseClass * b, bool new_instance, size_t interfaces_index)
{
ClassGlobalMap::iterator it = interfaceVtblMap.find(b->base);
if (it != interfaceVtblMap.end())
return it->second;
IF_LOG Logger::println("Building vtbl for implementation of interface %s in class %s",
b->base->toPrettyChars(), aggrdecl->toPrettyChars());
LOG_SCOPE;
ClassDeclaration* cd = aggrdecl->isClassDeclaration();
assert(cd && "not a class aggregate");
FuncDeclarations vtbl_array;
b->fillVtbl(cd, &vtbl_array, new_instance);
std::vector<llvm::Constant*> constants;
constants.reserve(vtbl_array.dim);
if (!b->base->isCPPinterface()) { // skip interface info for CPP interfaces
// start with the interface info
VarDeclarationIter interfaces_idx(ClassDeclaration::classinfo->fields, 3);
// index into the interfaces array
llvm::Constant* idxs[2] = {
DtoConstSize_t(0),
DtoConstSize_t(interfaces_index)
};
llvm::Constant* c = llvm::ConstantExpr::getGetElementPtr(
getInterfaceArraySymbol(), idxs, true);
constants.push_back(c);
}
// add virtual function pointers
size_t n = vtbl_array.dim;
for (size_t i = b->base->vtblOffset(); i < n; i++)
{
Dsymbol* dsym = static_cast<Dsymbol*>(vtbl_array.data[i]);
if (dsym == NULL)
{
// FIXME
// why is this null?
// happens for mini/s.d
constants.push_back(getNullValue(getVoidPtrType()));
continue;
}
FuncDeclaration* fd = dsym->isFuncDeclaration();
assert(fd && "vtbl entry not a function");
assert((!fd->isAbstract() || fd->fbody) &&
"null symbol in interface implementation vtable");
fd->codegen(Type::sir);
assert(fd->ir.irFunc && "invalid vtbl function");
LLFunction *fn = fd->ir.irFunc->func;
// If the base is a cpp interface, 'this' parameter is a pointer to
// the interface not the underlying object as expected. Instead of
// the function, we place into the vtable a small wrapper, called thunk,
// that casts 'this' to the object and then pass it to the real function.
if (b->base->isCPPinterface()) {
TypeFunction *f = (TypeFunction*)fd->type->toBasetype();
assert(f->fty.arg_this);
// create the thunk function
OutBuffer name;
name.writestring("Th");
name.printf("%i", b->offset);
name.writestring(fd->mangle());
LLFunction *thunk = LLFunction::Create(isaFunction(fn->getType()->getContainedType(0)),
DtoLinkage(fd), name.toChars(), gIR->module);
// create entry and end blocks
llvm::BasicBlock* beginbb = llvm::BasicBlock::Create(gIR->context(), "entry", thunk);
llvm::BasicBlock* endbb = llvm::BasicBlock::Create(gIR->context(), "endentry", thunk);
gIR->scopes.push_back(IRScope(beginbb, endbb));
// copy the function parameters, so later we can pass them to the real function
std::vector<LLValue*> args;
llvm::Function::arg_iterator iarg = thunk->arg_begin();
for (; iarg != thunk->arg_end(); ++iarg)
args.push_back(iarg);
// cast 'this' to Object
LLValue* &thisArg = args[(f->fty.arg_sret == 0) ? 0 : 1];
LLType* thisType = thisArg->getType();
thisArg = DtoBitCast(thisArg, getVoidPtrType());
thisArg = DtoGEP1(thisArg, DtoConstInt(-b->offset));
thisArg = DtoBitCast(thisArg, thisType);
// call the real vtbl function.
LLValue *retVal = gIR->ir->CreateCall(fn, args);
// return from the thunk
if (thunk->getReturnType() == LLType::getVoidTy(gIR->context()))
llvm::ReturnInst::Create(gIR->context(), beginbb);
else
llvm::ReturnInst::Create(gIR->context(), retVal, beginbb);
// clean up
gIR->scopes.pop_back();
thunk->getBasicBlockList().pop_back();
fn = thunk;
}
constants.push_back(fn);
}
// build the vtbl constant
llvm::Constant* vtbl_constant = LLConstantStruct::getAnon(gIR->context(), constants, false);
// create the global variable to hold it
llvm::GlobalValue::LinkageTypes _linkage = DtoExternalLinkage(aggrdecl);
std::string mangle("_D");
mangle.append(cd->mangle());
mangle.append("11__interface");
mangle.append(b->base->mangle());
mangle.append("6__vtblZ");
llvm::GlobalVariable* GV = getOrCreateGlobal(cd->loc,
*gIR->module,
vtbl_constant->getType(),
true,
_linkage,
vtbl_constant,
mangle
);
// insert into the vtbl map
interfaceVtblMap.insert(std::make_pair(b->base, GV));
return GV;
}
void VarDeclaration::codegen(Ir* p)
{
Logger::print("VarDeclaration::codegen(): %s | %s\n", toChars(), type->toChars());
LOG_SCOPE;
if (type->ty == Terror)
{ error("had semantic errors when compiling");
return;
}
// just forward aliases
if (aliassym)
{
Logger::println("alias sym");
toAlias()->codegen(p);
return;
}
// output the parent aggregate first
if (AggregateDeclaration* ad = isMember())
ad->codegen(p);
// global variable
if (isDataseg() || (storage_class & (STCconst | STCimmutable) && init))
{
Logger::println("data segment");
#if 0 // TODO:
assert(!(storage_class & STCmanifest) &&
"manifest constant being codegen'd!");
#endif
// don't duplicate work
if (this->ir.resolved) return;
this->ir.resolved = true;
this->ir.declared = true;
this->ir.irGlobal = new IrGlobal(this);
Logger::println("parent: %s (%s)", parent->toChars(), parent->kind());
const bool isLLConst = isConst() && init;
const llvm::GlobalValue::LinkageTypes llLinkage = DtoLinkage(this);
assert(!ir.initialized);
ir.initialized = gIR->dmodule;
std::string llName(mangle());
// Since the type of a global must exactly match the type of its
// initializer, we cannot know the type until after we have emitted the
// latter (e.g. in case of unions, …). However, it is legal for the
// initializer to refer to the address of the variable. Thus, we first
// create a global with the generic type (note the assignment to
// this->ir.irGlobal->value!), and in case we also do an initializer
// with a different type later, swap it out and replace any existing
// uses with bitcasts to the previous type.
llvm::GlobalVariable* gvar = getOrCreateGlobal(loc, *gIR->module,
i1ToI8(DtoType(type)), isLLConst, llLinkage, 0, llName,
isThreadlocal());
this->ir.irGlobal->value = gvar;
// Check if we are defining or just declaring the global in this module.
if (!(storage_class & STCextern) && mustDefineSymbol(this))
{
// Build the initializer. Might use this->ir.irGlobal->value!
LLConstant *initVal = DtoConstInitializer(loc, type, init);
// In case of type mismatch, swap out the variable.
if (initVal->getType() != gvar->getType()->getElementType())
{
llvm::GlobalVariable* newGvar = getOrCreateGlobal(loc,
*gIR->module, initVal->getType(), isLLConst, llLinkage, 0,
"", // We take on the name of the old global below.
isThreadlocal());
newGvar->takeName(gvar);
llvm::Constant* newValue =
llvm::ConstantExpr::getBitCast(newGvar, gvar->getType());
gvar->replaceAllUsesWith(newValue);
gvar->eraseFromParent();
gvar = newGvar;
this->ir.irGlobal->value = newGvar;
}
// Now, set the initializer.
assert(!ir.irGlobal->constInit);
ir.irGlobal->constInit = initVal;
gvar->setInitializer(initVal);
// Also set up the edbug info.
DtoDwarfGlobalVariable(gvar, this);
}
// Set the alignment (it is important not to use type->alignsize because
// VarDeclarations can have an align() attribute independent of the type
// as well).
if (alignment != STRUCTALIGN_DEFAULT)
gvar->setAlignment(alignment);
// If this global is used from a naked function, we need to create an
// artificial "use" for it, or it could be removed by the optimizer if
// the only reference to it is in inline asm.
if (nakedUse)
gIR->usedArray.push_back(DtoBitCast(gvar, getVoidPtrType()));
if (Logger::enabled())
Logger::cout() << *gvar << '\n';
}
}
