view gen/tollvm.cpp @ 1650:40bd4a0d4870

Update to work with LLVM 2.7. Removed use of dyn_cast, llvm no compiles without exceptions and rtti by default. We do need exceptions for the libconfig stuff, but rtti isn't necessary (anymore). Debug info needs to be rewritten, as in LLVM 2.7 the format has completely changed. To have something to look at while rewriting, the old code has been wrapped inside #ifndef DISABLE_DEBUG_INFO , this means that you have to define this to compile at the moment. Updated tango 0.99.9 patch to include updated EH runtime code, which is needed for LLVM 2.7 as well.
author Tomas Lindquist Olsen
date Wed, 19 May 2010 12:42:32 +0200
parents 9176437d98be
children
line wrap: on
line source

#include "gen/llvm.h"

#include "dsymbol.h"
#include "aggregate.h"
#include "declaration.h"
#include "init.h"
#include "module.h"

#include "gen/tollvm.h"
#include "gen/irstate.h"
#include "gen/logger.h"
#include "gen/runtime.h"
#include "gen/arrays.h"
#include "gen/dvalue.h"
#include "gen/functions.h"
#include "gen/structs.h"
#include "gen/classes.h"
#include "gen/typeinf.h"
#include "gen/complex.h"
#include "gen/llvmhelpers.h"
#include "gen/linkage.h"

#include "ir/irtype.h"
#include "ir/irtypeclass.h"
#include "ir/irtypefunction.h"

bool DtoIsPassedByRef(Type* type)
{
    Type* typ = type->toBasetype();
    TY t = typ->ty;
    return (t == Tstruct || t == Tsarray);
}

unsigned DtoShouldExtend(Type* type)
{
    type = type->toBasetype();
    if (type->isintegral())
    {
        switch(type->ty)
        {
        case Tint8:
        case Tint16:
            return llvm::Attribute::SExt;

        case Tuns8:
        case Tuns16:
            return llvm::Attribute::ZExt;
        }
    }
    return llvm::Attribute::None;
}

const LLType* DtoType(Type* t)
{
    t = stripModifiers( t );

    if (t->irtype)
    {
        return t->irtype->get();
    }

    IF_LOG Logger::println("Building type: %s", t->toChars());

    assert(t);
    switch (t->ty)
    {
    // basic types
    case Tvoid:
    case Tint8:
    case Tuns8:
    case Tint16:
    case Tuns16:
    case Tint32:
    case Tuns32:
    case Tint64:
    case Tuns64:
    case Tfloat32:
    case Tfloat64:
    case Tfloat80:
    case Timaginary32:
    case Timaginary64:
    case Timaginary80:
    case Tcomplex32:
    case Tcomplex64:
    case Tcomplex80:
    //case Tbit:
    case Tbool:
    case Tchar:
    case Twchar:
    case Tdchar:
    {
        t->irtype = new IrTypeBasic(t);
        return t->irtype->buildType();
    }

    // pointers
    case Tpointer:
    {
        t->irtype = new IrTypePointer(t);
        return t->irtype->buildType();
    }

    // arrays
    case Tarray:
    {
        t->irtype = new IrTypeArray(t);
        return t->irtype->buildType();
    }

    case Tsarray:
    {
        t->irtype = new IrTypeSArray(t);
        return t->irtype->buildType();
    }

    // aggregates
    case Tstruct:    {
        TypeStruct* ts = (TypeStruct*)t;
        t->irtype = new IrTypeStruct(ts->sym);
        return t->irtype->buildType();
    }
    case Tclass:    {
        TypeClass* tc = (TypeClass*)t;
        t->irtype = new IrTypeClass(tc->sym);
        return t->irtype->buildType();
    }

    // functions
    case Tfunction:
    {
        t->irtype = new IrTypeFunction(t);
        return t->irtype->buildType();
    }

    // delegates
    case Tdelegate:
    {
        t->irtype = new IrTypeDelegate(t);
        return t->irtype->buildType();
    }

    // typedefs
    // enum

    // FIXME: maybe just call toBasetype first ?
    case Ttypedef:
    case Tenum:
    {
        Type* bt = t->toBasetype();
        assert(bt);
        return DtoType(bt);
    }

    // associative arrays
    case Taarray:
        return getVoidPtrType();

/*
    Not needed atm as VarDecls for tuples are rewritten as a string of
    VarDecls for the fields (u -> _u_field_0, ...)

    case Ttuple:
    {
        TypeTuple* ttupl = (TypeTuple*)t;
        return DtoStructTypeFromArguments(ttupl->arguments);
    }
*/

    default:
        printf("trying to convert unknown type '%s' with value %d\n", t->toChars(), t->ty);
        assert(0);
    }
    return 0;
}

//////////////////////////////////////////////////////////////////////////////////////////

/*
const LLType* DtoStructTypeFromArguments(Arguments* arguments)
{
    if (!arguments)
        return LLType::getVoidTy(gIR->context());

    std::vector<const LLType*> types;
    for (size_t i = 0; i < arguments->dim; i++)
    {
        Argument *arg = (Argument *)arguments->data[i];
        assert(arg && arg->type);

        types.push_back(DtoType(arg->type));
    }
    return LLStructType::get(types);
}
*/

//////////////////////////////////////////////////////////////////////////////////////////

const LLType* DtoTypeNotVoid(Type* t)
{
    const LLType* lt = DtoType(t);
    if (lt == LLType::getVoidTy(gIR->context()))
        return LLType::getInt8Ty(gIR->context());
    return lt;
}

//////////////////////////////////////////////////////////////////////////////////////////

LLValue* DtoDelegateEquals(TOK op, LLValue* lhs, LLValue* rhs)
{
    Logger::println("Doing delegate equality");
    llvm::Value *b1, *b2;
    if (rhs == NULL)
    {
        rhs = LLConstant::getNullValue(lhs->getType());
    }

    LLValue* l = gIR->ir->CreateExtractValue(lhs, 0);
    LLValue* r = gIR->ir->CreateExtractValue(rhs, 0);
    b1 = gIR->ir->CreateICmp(llvm::ICmpInst::ICMP_EQ,l,r,"tmp");

    l = gIR->ir->CreateExtractValue(lhs, 1);
    r = gIR->ir->CreateExtractValue(rhs, 1);
    b2 = gIR->ir->CreateICmp(llvm::ICmpInst::ICMP_EQ,l,r,"tmp");

    LLValue* b = gIR->ir->CreateAnd(b1,b2,"tmp");

    if (op == TOKnotequal || op == TOKnotidentity)
        return gIR->ir->CreateNot(b,"tmp");

    return b;
}

//////////////////////////////////////////////////////////////////////////////////////////

LLGlobalValue::LinkageTypes DtoLinkage(Dsymbol* sym)
{
    // global variable
    if (VarDeclaration* vd = sym->isVarDeclaration())
    {
        if (mustDefineSymbol(vd))
            Logger::println("Variable %savailable externally: %s", (vd->availableExternally ? "" : "not "), vd->toChars());
        // generated by inlining semantics run
        if (vd->availableExternally && mustDefineSymbol(sym))
            return llvm::GlobalValue::AvailableExternallyLinkage;
        // template
        if (needsTemplateLinkage(sym))
            return templateLinkage;
    }
    // function
    else if (FuncDeclaration* fdecl = sym->isFuncDeclaration())
    {
        if (mustDefineSymbol(fdecl))
            Logger::println("Function %savailable externally: %s", (fdecl->availableExternally ? "" : "not "), fdecl->toChars());
        assert(fdecl->type->ty == Tfunction);
        TypeFunction* ft = (TypeFunction*)fdecl->type;

        // intrinsics are always external
        if (fdecl->llvmInternal == LLVMintrinsic)
            return llvm::GlobalValue::ExternalLinkage;
        // generated by inlining semantics run
        if (fdecl->availableExternally && mustDefineSymbol(sym))
            return llvm::GlobalValue::AvailableExternallyLinkage;
        // array operations are always template linkage
        if (fdecl->isArrayOp)
            return templateLinkage;
        // template instances should have weak linkage
        // but only if there's a body, and it's not naked
        // otherwise we make it external
        else if (needsTemplateLinkage(fdecl) && fdecl->fbody && !fdecl->naked)
            return templateLinkage;
        // extern(C) functions are always external
        else if (ft->linkage == LINKc)
            return llvm::GlobalValue::ExternalLinkage;
    }
    // class
    else if (ClassDeclaration* cd = sym->isClassDeclaration())
    {
        if (mustDefineSymbol(cd))
            Logger::println("Class %savailable externally: %s", (cd->availableExternally ? "" : "not "), vd->toChars());
        // generated by inlining semantics run
        if (cd->availableExternally && mustDefineSymbol(sym))
            return llvm::GlobalValue::AvailableExternallyLinkage;
        // template
        if (needsTemplateLinkage(cd))
            return templateLinkage;
    }
    else
    {
        assert(0 && "not global/function");
    }

    // The following breaks for nested naked functions and other declarations, so check for that.
    bool skipNestedCheck = !mustDefineSymbol(sym);
    if (FuncDeclaration* fd = sym->isFuncDeclaration())
        skipNestedCheck = (fd->naked != 0);

    // Any symbol nested in a function can't be referenced directly from
    // outside that function, so we can give such symbols internal linkage.
    // This holds even if nested indirectly, such as member functions of
    // aggregates nested in functions.
    //
    // Note: This must be checked after things like template member-ness or
    // symbols nested in templates would get duplicated for each module,
    // breaking things like
    // ---
    // int counter(T)() { static int i; return i++; }"
    // ---
    // if instances get emitted in multiple object files because they'd use
    // different instances of 'i'.
    if (!skipNestedCheck)
        for (Dsymbol* parent = sym->parent; parent ; parent = parent->parent) {
            if (parent->isFuncDeclaration())
                return llvm::GlobalValue::InternalLinkage;
        }

    // default to external linkage
    return llvm::GlobalValue::ExternalLinkage;
}

static bool isAvailableExternally(Dsymbol* sym)
{
    if (VarDeclaration* vd = sym->isVarDeclaration())
        return vd->availableExternally;
    if (FuncDeclaration* fd = sym->isFuncDeclaration())
        return fd->availableExternally;
    if (AggregateDeclaration* ad = sym->isAggregateDeclaration())
        return ad->availableExternally;
    return false;
}

llvm::GlobalValue::LinkageTypes DtoInternalLinkage(Dsymbol* sym)
{
    if (needsTemplateLinkage(sym)) {
        if (isAvailableExternally(sym) && mustDefineSymbol(sym))
            return llvm::GlobalValue::AvailableExternallyLinkage;
        return templateLinkage;
    }
    else
        return llvm::GlobalValue::InternalLinkage;
}

llvm::GlobalValue::LinkageTypes DtoExternalLinkage(Dsymbol* sym)
{
    if (isAvailableExternally(sym) && mustDefineSymbol(sym))
        return llvm::GlobalValue::AvailableExternallyLinkage;
    if (needsTemplateLinkage(sym))
        return templateLinkage;
    else
        return llvm::GlobalValue::ExternalLinkage;
}

//////////////////////////////////////////////////////////////////////////////////////////

LLValue* DtoPointedType(LLValue* ptr, LLValue* val)
{
    const LLType* ptrTy = ptr->getType()->getContainedType(0);
    const LLType* valTy = val->getType();
    // ptr points to val's type
    if (ptrTy == valTy)
    {
        return val;
    }
    // ptr is integer pointer
    else if (ptrTy->isIntegerTy())
    {
        // val is integer
        assert(valTy->isInteger());
        const LLIntegerType* pt = llvm::cast<const LLIntegerType>(ptrTy);
        const LLIntegerType* vt = llvm::cast<const LLIntegerType>(valTy);
        if (pt->getBitWidth() < vt->getBitWidth()) {
            return new llvm::TruncInst(val, pt, "tmp", gIR->scopebb());
        }
        else
        assert(0);
    }
    // something else unsupported
    else
    {
        if (Logger::enabled())
            Logger::cout() << *ptrTy << '|' << *valTy << '\n';
        assert(0);
    }
    return 0;
}

//////////////////////////////////////////////////////////////////////////////////////////

const LLIntegerType* DtoSize_t()
{
    // the type of size_t does not change once set
    static const LLIntegerType* t = NULL;
    if (t == NULL)
        t = (global.params.is64bit) ? LLType::getInt64Ty(gIR->context()) : LLType::getInt32Ty(gIR->context());
    return t;
}

//////////////////////////////////////////////////////////////////////////////////////////

LLValue* DtoGEP1(LLValue* ptr, LLValue* i0, const char* var, llvm::BasicBlock* bb)
{
    return llvm::GetElementPtrInst::Create(ptr, i0, var?var:"tmp", bb?bb:gIR->scopebb());
}

//////////////////////////////////////////////////////////////////////////////////////////

LLValue* DtoGEP(LLValue* ptr, LLValue* i0, LLValue* i1, const char* var, llvm::BasicBlock* bb)
{
    LLSmallVector<LLValue*,2> v(2);
    v[0] = i0;
    v[1] = i1;
    return llvm::GetElementPtrInst::Create(ptr, v.begin(), v.end(), var?var:"tmp", bb?bb:gIR->scopebb());
}

//////////////////////////////////////////////////////////////////////////////////////////

LLValue* DtoGEPi1(LLValue* ptr, unsigned i, const char* var, llvm::BasicBlock* bb)
{
    return llvm::GetElementPtrInst::Create(ptr, DtoConstUint(i), var?var:"tmp", bb?bb:gIR->scopebb());
}

//////////////////////////////////////////////////////////////////////////////////////////

LLValue* DtoGEPi(LLValue* ptr, unsigned i0, unsigned i1, const char* var, llvm::BasicBlock* bb)
{
    LLSmallVector<LLValue*,2> v(2);
    v[0] = DtoConstUint(i0);
    v[1] = DtoConstUint(i1);
    return llvm::GetElementPtrInst::Create(ptr, v.begin(), v.end(), var?var:"tmp", bb?bb:gIR->scopebb());
}

//////////////////////////////////////////////////////////////////////////////////////////

LLConstant* DtoGEPi(LLConstant* ptr, unsigned i0, unsigned i1)
{
    LLValue* v[2] = { DtoConstUint(i0), DtoConstUint(i1) };
    return llvm::ConstantExpr::getGetElementPtr(ptr, v, 2);
}

//////////////////////////////////////////////////////////////////////////////////////////

void DtoMemSet(LLValue* dst, LLValue* val, LLValue* nbytes)
{
    dst = DtoBitCast(dst,getVoidPtrType());

    const LLType* intTy = DtoSize_t();
    llvm::Function* fn = llvm::Intrinsic::getDeclaration(gIR->module,
        llvm::Intrinsic::memset, &intTy, 1);

    gIR->ir->CreateCall4(fn, dst, val, nbytes, DtoConstUint(0), "");
}

//////////////////////////////////////////////////////////////////////////////////////////

void DtoMemSetZero(LLValue* dst, LLValue* nbytes)
{
    DtoMemSet(dst, DtoConstUbyte(0), nbytes);
}

//////////////////////////////////////////////////////////////////////////////////////////

void DtoMemCpy(LLValue* dst, LLValue* src, LLValue* nbytes, unsigned align)
{
    dst = DtoBitCast(dst,getVoidPtrType());
    src = DtoBitCast(src,getVoidPtrType());

    const LLType* intTy = DtoSize_t();
    llvm::Function* fn = llvm::Intrinsic::getDeclaration(gIR->module,
        llvm::Intrinsic::memcpy, &intTy, 1);

    gIR->ir->CreateCall4(fn, dst, src, nbytes, DtoConstUint(align), "");
}

//////////////////////////////////////////////////////////////////////////////////////////

LLValue* DtoMemCmp(LLValue* lhs, LLValue* rhs, LLValue* nbytes)
{
    // int memcmp ( const void * ptr1, const void * ptr2, size_t num );

    LLFunction* fn = gIR->module->getFunction("memcmp");
    if (!fn)
    {
        std::vector<const LLType*> params(3);
        params[0] = getVoidPtrType();
        params[1] = getVoidPtrType();
        params[2] = DtoSize_t();
        const LLFunctionType* fty = LLFunctionType::get(LLType::getInt32Ty(gIR->context()), params, false);
        fn = LLFunction::Create(fty, LLGlobalValue::ExternalLinkage, "memcmp", gIR->module);
    }

    lhs = DtoBitCast(lhs,getVoidPtrType());
    rhs = DtoBitCast(rhs,getVoidPtrType());

    return gIR->ir->CreateCall3(fn, lhs, rhs, nbytes, "tmp");
}

//////////////////////////////////////////////////////////////////////////////////////////

void DtoAggrZeroInit(LLValue* v)
{
    uint64_t n = getTypeStoreSize(v->getType()->getContainedType(0));
    DtoMemSetZero(v, DtoConstSize_t(n));
}

//////////////////////////////////////////////////////////////////////////////////////////

void DtoAggrCopy(LLValue* dst, LLValue* src)
{
    uint64_t n = getTypeStoreSize(dst->getType()->getContainedType(0));
    DtoMemCpy(dst, src, DtoConstSize_t(n));
}

//////////////////////////////////////////////////////////////////////////////////////////

void DtoMemoryBarrier(bool ll, bool ls, bool sl, bool ss, bool device)
{
    llvm::Function* fn = GET_INTRINSIC_DECL(memory_barrier);
    assert(fn != NULL);

    LLSmallVector<LLValue*, 5> llargs;
    llargs.push_back(DtoConstBool(ll));
    llargs.push_back(DtoConstBool(ls));
    llargs.push_back(DtoConstBool(sl));
    llargs.push_back(DtoConstBool(ss));
    llargs.push_back(DtoConstBool(device));

    llvm::CallInst::Create(fn, llargs.begin(), llargs.end(), "", gIR->scopebb());
}

//////////////////////////////////////////////////////////////////////////////////////////

llvm::ConstantInt* DtoConstSize_t(uint64_t i)
{
    return LLConstantInt::get(DtoSize_t(), i, false);
}
llvm::ConstantInt* DtoConstUint(unsigned i)
{
    return LLConstantInt::get(LLType::getInt32Ty(gIR->context()), i, false);
}
llvm::ConstantInt* DtoConstInt(int i)
{
    return LLConstantInt::get(LLType::getInt32Ty(gIR->context()), i, true);
}
LLConstant* DtoConstBool(bool b)
{
    return LLConstantInt::get(LLType::getInt1Ty(gIR->context()), b, false);
}
llvm::ConstantInt* DtoConstUbyte(unsigned char i)
{
    return LLConstantInt::get(LLType::getInt8Ty(gIR->context()), i, false);
}

LLConstant* DtoConstFP(Type* t, long double value)
{
    const LLType* llty = DtoType(t);
    assert(llty->isFloatingPoint());

    if(llty == LLType::getFloatTy(gIR->context()) || llty == LLType::getDoubleTy(gIR->context()))
        return LLConstantFP::get(llty, value);
    else if(llty == LLType::getX86_FP80Ty(gIR->context())) {
        uint64_t bits[] = {0, 0};
        bits[0] = *(uint64_t*)&value;
        bits[1] = *(uint16_t*)((uint64_t*)&value + 1);
        return LLConstantFP::get(gIR->context(), APFloat(APInt(80, 2, bits)));
    } else {
        assert(0 && "Unknown floating point type encountered");
    }
}

//////////////////////////////////////////////////////////////////////////////////////////

LLConstant* DtoConstString(const char* str)
{
    llvm::StringRef s(str?str:"");
    LLConstant* init = LLConstantArray::get(gIR->context(), s, true);
    llvm::GlobalVariable* gvar = new llvm::GlobalVariable(
        *gIR->module, init->getType(), true,llvm::GlobalValue::InternalLinkage, init, ".str");
    LLConstant* idxs[2] = { DtoConstUint(0), DtoConstUint(0) };
    return DtoConstSlice(
        DtoConstSize_t(s.size()),
        llvm::ConstantExpr::getGetElementPtr(gvar,idxs,2)
    );
}
LLConstant* DtoConstStringPtr(const char* str, const char* section)
{
    llvm::StringRef s(str);
    LLConstant* init = LLConstantArray::get(gIR->context(), s, true);
    llvm::GlobalVariable* gvar = new llvm::GlobalVariable(
        *gIR->module, init->getType(), true,llvm::GlobalValue::InternalLinkage, init, ".str");
    if (section) gvar->setSection(section);
    LLConstant* idxs[2] = { DtoConstUint(0), DtoConstUint(0) };
    return llvm::ConstantExpr::getGetElementPtr(gvar,idxs,2);
}

//////////////////////////////////////////////////////////////////////////////////////////

LLValue* DtoLoad(LLValue* src, const char* name)
{
//     if (Logger::enabled())
//         Logger::cout() << "loading " << *src <<  '\n';
    llvm::LoadInst* ld = gIR->ir->CreateLoad(src, name ? name : "tmp");
    //ld->setVolatile(gIR->func()->inVolatile);
    return ld;
}

// Like DtoLoad, but the pointer is guaranteed to be aligned appropriately for the type.
LLValue* DtoAlignedLoad(LLValue* src, const char* name)
{
    llvm::LoadInst* ld = gIR->ir->CreateLoad(src, name ? name : "tmp");
    ld->setAlignment(getABITypeAlign(ld->getType()));
    return ld;
}


void DtoStore(LLValue* src, LLValue* dst)
{
//     if (Logger::enabled())
//         Logger::cout() << "storing " << *src << " into " << *dst << '\n';
    LLValue* st = gIR->ir->CreateStore(src,dst);
    //st->setVolatile(gIR->func()->inVolatile);
}

// Like DtoStore, but the pointer is guaranteed to be aligned appropriately for the type.
void DtoAlignedStore(LLValue* src, LLValue* dst)
{
    llvm::StoreInst* st = gIR->ir->CreateStore(src,dst);
    st->setAlignment(getABITypeAlign(src->getType()));
}

//////////////////////////////////////////////////////////////////////////////////////////

LLValue* DtoBitCast(LLValue* v, const LLType* t, const char* name)
{
    if (v->getType() == t)
        return v;
    assert(!isaStruct(t));
    return gIR->ir->CreateBitCast(v, t, name ? name : "tmp");
}

LLConstant* DtoBitCast(LLConstant* v, const LLType* t)
{
    if (v->getType() == t)
        return v;
    return llvm::ConstantExpr::getBitCast(v, t);
}

//////////////////////////////////////////////////////////////////////////////////////////

LLValue* DtoInsertValue(LLValue* aggr, LLValue* v, unsigned idx)
{
    return gIR->ir->CreateInsertValue(aggr, v, idx);
}

LLValue* DtoExtractValue(LLValue* aggr, unsigned idx)
{
    return gIR->ir->CreateExtractValue(aggr, idx);
}

//////////////////////////////////////////////////////////////////////////////////////////

const LLPointerType* isaPointer(LLValue* v)
{
    return llvm::dyn_cast<LLPointerType>(v->getType());
}

const LLPointerType* isaPointer(const LLType* t)
{
    return llvm::dyn_cast<LLPointerType>(t);
}

const LLArrayType* isaArray(LLValue* v)
{
    return llvm::dyn_cast<LLArrayType>(v->getType());
}

const LLArrayType* isaArray(const LLType* t)
{
    return llvm::dyn_cast<LLArrayType>(t);
}

const LLStructType* isaStruct(LLValue* v)
{
    return llvm::dyn_cast<LLStructType>(v->getType());
}

const LLStructType* isaStruct(const LLType* t)
{
    return llvm::dyn_cast<LLStructType>(t);
}

const LLFunctionType* isaFunction(LLValue* v)
{
    return llvm::dyn_cast<LLFunctionType>(v->getType());
}

const LLFunctionType* isaFunction(const LLType* t)
{
    return llvm::dyn_cast<LLFunctionType>(t);
}

LLConstant* isaConstant(LLValue* v)
{
    return llvm::dyn_cast<llvm::Constant>(v);
}

llvm::ConstantInt* isaConstantInt(LLValue* v)
{
    return llvm::dyn_cast<llvm::ConstantInt>(v);
}

llvm::Argument* isaArgument(LLValue* v)
{
    return llvm::dyn_cast<llvm::Argument>(v);
}

llvm::GlobalVariable* isaGlobalVar(LLValue* v)
{
    return llvm::dyn_cast<llvm::GlobalVariable>(v);
}

//////////////////////////////////////////////////////////////////////////////////////////

const LLPointerType* getPtrToType(const LLType* t)
{
    if (t == LLType::getVoidTy(gIR->context()))
        t = LLType::getInt8Ty(gIR->context());
    return LLPointerType::get(t, 0);
}

const LLPointerType* getVoidPtrType()
{
    return getPtrToType(LLType::getInt8Ty(gIR->context()));
}

llvm::ConstantPointerNull* getNullPtr(const LLType* t)
{
    const LLPointerType* pt = llvm::cast<LLPointerType>(t);
    return llvm::ConstantPointerNull::get(pt);
}

LLConstant* getNullValue(const LLType* t)
{
    return LLConstant::getNullValue(t);
}

//////////////////////////////////////////////////////////////////////////////////////////

size_t getTypeBitSize(const LLType* t)
{
    return gTargetData->getTypeSizeInBits(t);
}

size_t getTypeStoreSize(const LLType* t)
{
    return gTargetData->getTypeStoreSize(t);
}

size_t getTypePaddedSize(const LLType* t)
{
    size_t sz = gTargetData->getTypeAllocSize(t);
    //Logger::cout() << "abi type size of: " << *t << " == " << sz << '\n';
    return sz;
}

unsigned char getABITypeAlign(const LLType* t)
{
    return gTargetData->getABITypeAlignment(t);
}

unsigned char getPrefTypeAlign(const LLType* t)
{
    return gTargetData->getPrefTypeAlignment(t);
}

const LLType* getBiggestType(const LLType** begin, size_t n)
{
    const LLType* bigTy = 0;
    size_t bigSize = 0;
    size_t bigAlign = 0;

    const LLType** end = begin+n;
    while (begin != end)
    {
        const LLType* T = *begin;

        size_t sz = getTypePaddedSize(T);
        size_t ali = getABITypeAlign(T);
        if (sz > bigSize || (sz == bigSize && ali > bigAlign))
        {
            bigTy = T;
            bigSize = sz;
            bigAlign = ali;
        }

        ++begin;
    }

    // will be null for n==0
    return bigTy;
}

//////////////////////////////////////////////////////////////////////////////////////////

const LLStructType* DtoInterfaceInfoType()
{
    if (gIR->interfaceInfoType)
        return gIR->interfaceInfoType;

    // build interface info type
    std::vector<const LLType*> types;
    // ClassInfo classinfo
    ClassDeclaration* cd2 = ClassDeclaration::classinfo;
    DtoResolveClass(cd2);
    types.push_back(DtoType(cd2->type));
    // void*[] vtbl
    std::vector<const LLType*> vtbltypes;
    vtbltypes.push_back(DtoSize_t());
    const LLType* byteptrptrty = getPtrToType(getPtrToType(LLType::getInt8Ty(gIR->context())));
    vtbltypes.push_back(byteptrptrty);
    types.push_back(LLStructType::get(gIR->context(), vtbltypes));
    // int offset
    types.push_back(LLType::getInt32Ty(gIR->context()));
    // create type
    gIR->interfaceInfoType = LLStructType::get(gIR->context(), types);

    return gIR->interfaceInfoType;
}

//////////////////////////////////////////////////////////////////////////////////////////

const LLStructType* DtoMutexType()
{
    if (gIR->mutexType)
        return gIR->mutexType;

    // win32
    if (global.params.os == OSWindows)
    {
        // CRITICAL_SECTION.sizeof == 68
        std::vector<const LLType*> types(17, LLType::getInt32Ty(gIR->context()));
        return LLStructType::get(gIR->context(), types);
    }

    // FreeBSD
    else if (global.params.os == OSFreeBSD) {
        // Just a pointer
        return LLStructType::get(gIR->context(), DtoSize_t(), NULL);
    }

    // pthread_fastlock
    std::vector<const LLType*> types2;
    types2.push_back(DtoSize_t());
    types2.push_back(LLType::getInt32Ty(gIR->context()));
    const LLStructType* fastlock = LLStructType::get(gIR->context(), types2);

    // pthread_mutex
    std::vector<const LLType*> types1;
    types1.push_back(LLType::getInt32Ty(gIR->context()));
    types1.push_back(LLType::getInt32Ty(gIR->context()));
    types1.push_back(getVoidPtrType());
    types1.push_back(LLType::getInt32Ty(gIR->context()));
    types1.push_back(fastlock);
    const LLStructType* pmutex = LLStructType::get(gIR->context(), types1);

    // D_CRITICAL_SECTION
    LLOpaqueType* opaque = LLOpaqueType::get(gIR->context());
    std::vector<const LLType*> types;
    types.push_back(getPtrToType(opaque));
    types.push_back(pmutex);

    // resolve type
    pmutex = LLStructType::get(gIR->context(), types);
    LLPATypeHolder pa(pmutex);
    opaque->refineAbstractTypeTo(pa.get());
    pmutex = isaStruct(pa.get());

    gIR->mutexType = pmutex;
    gIR->module->addTypeName("D_CRITICAL_SECTION", pmutex);
    return pmutex;
}

//////////////////////////////////////////////////////////////////////////////////////////

const LLStructType* DtoModuleReferenceType()
{
    if (gIR->moduleRefType)
        return gIR->moduleRefType;

    // this is a recursive type so start out with the opaque
    LLOpaqueType* opaque = LLOpaqueType::get(gIR->context());

    // add members
    std::vector<const LLType*> types;
    types.push_back(getPtrToType(opaque));
    types.push_back(DtoType(Module::moduleinfo->type));

    // resolve type
    const LLStructType* st = LLStructType::get(gIR->context(), types);
    LLPATypeHolder pa(st);
    opaque->refineAbstractTypeTo(pa.get());
    st = isaStruct(pa.get());

    // done
    gIR->moduleRefType = st;
    gIR->module->addTypeName("ModuleReference", st);
    return st;
}

//////////////////////////////////////////////////////////////////////////////////////////

LLValue* DtoAggrPair(const LLType* type, LLValue* V1, LLValue* V2, const char* name)
{
    LLValue* res = llvm::UndefValue::get(type);
    res = gIR->ir->CreateInsertValue(res, V1, 0, "tmp");
    return gIR->ir->CreateInsertValue(res, V2, 1, name?name:"tmp");
}

LLValue* DtoAggrPair(LLValue* V1, LLValue* V2, const char* name)
{
    const LLType* t = LLStructType::get(gIR->context(), V1->getType(), V2->getType(), NULL);
    return DtoAggrPair(t, V1, V2, name);
}

LLValue* DtoAggrPaint(LLValue* aggr, const LLType* as)
{
    if (aggr->getType() == as)
        return aggr;

    LLValue* res = llvm::UndefValue::get(as);

    LLValue* V = gIR->ir->CreateExtractValue(aggr, 0, "tmp");;
    V = DtoBitCast(V, as->getContainedType(0));
    res = gIR->ir->CreateInsertValue(res, V, 0, "tmp");

    V = gIR->ir->CreateExtractValue(aggr, 1, "tmp");;
    V = DtoBitCast(V, as->getContainedType(1));
    return gIR->ir->CreateInsertValue(res, V, 1, "tmp");
}

LLValue* DtoAggrPairSwap(LLValue* aggr)
{
    Logger::println("swapping aggr pair");
    LLValue* r = gIR->ir->CreateExtractValue(aggr, 0);
    LLValue* i = gIR->ir->CreateExtractValue(aggr, 1);
    return DtoAggrPair(i, r, "swapped");
}