view gen/tollvm.cpp @ 86:fd32135dca3e trunk

[svn r90] Major updates to the gen directory. Redesigned the 'elem' struct. Much more... !!! Lots of bugfixes. Added support for special foreach on strings. Added std.array, std.utf, std.ctype and std.uni to phobos. Changed all the .c files in the gen dir to .cpp (it *is* C++ after all)
author lindquist
date Sat, 03 Nov 2007 14:44:58 +0100
parents gen/tollvm.c@f869c636a113
children 058d3925950e
line wrap: on
line source

#include <iostream>

#include "gen/llvm.h"

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

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

Type* DtoDType(Type* t)
{
    if (t->ty == Ttypedef) {
        Type* bt = t->toBasetype();
        assert(bt);
        return DtoDType(bt);
    }
    return t;
}

const llvm::Type* DtoType(Type* t)
{
    assert(t);
    switch (t->ty)
    {
    // integers
    case Tint8:
    case Tuns8:
    case Tchar:
        return (const llvm::Type*)llvm::Type::Int8Ty;
    case Tint16:
    case Tuns16:
    case Twchar:
        return (const llvm::Type*)llvm::Type::Int16Ty;
    case Tint32:
    case Tuns32:
    case Tdchar:
        return (const llvm::Type*)llvm::Type::Int32Ty;
    case Tint64:
    case Tuns64:
        return (const llvm::Type*)llvm::Type::Int64Ty;

    case Tbool:
        return (const llvm::Type*)llvm::ConstantInt::getTrue()->getType();

    // floats
    case Tfloat32:
    case Timaginary32:
        return llvm::Type::FloatTy;
    case Tfloat64:
    case Timaginary64:
    case Tfloat80:
    case Timaginary80:
        return llvm::Type::DoubleTy;

    // complex
    case Tcomplex32:
    case Tcomplex64:
    case Tcomplex80:
        assert(0 && "complex number types not yet implemented");

    // pointers
    case Tpointer: {
        assert(t->next);
        if (t->next->ty == Tvoid)
            return (const llvm::Type*)llvm::PointerType::get(llvm::Type::Int8Ty);
        else
            return (const llvm::Type*)llvm::PointerType::get(DtoType(t->next));
    }

    // arrays
    case Tarray:
        return DtoArrayType(t);
    case Tsarray:
        return DtoStaticArrayType(t);

    // void
    case Tvoid:
        return llvm::Type::VoidTy;

    // aggregates
    case Tstruct:    {
        if (t->llvmType == 0)
        {
            // recursive or cyclic declaration
            if (!gIR->structs.empty())
            {
                IRStruct* found = 0;
                for (IRState::StructVector::iterator i=gIR->structs.begin(); i!=gIR->structs.end(); ++i)
                {
                    if (t == i->type)
                    {
                        return i->recty.get();
                    }
                }
            }

            // forward declaration
            TypeStruct* ts = (TypeStruct*)t;
            assert(ts->sym);
            ts->sym->toObjFile();
        }
        return t->llvmType;
    }

    case Tclass:    {
        if (t->llvmType == 0)
        {
            // recursive or cyclic declaration
            if (!gIR->structs.empty())
            {
                IRStruct* found = 0;
                for (IRState::StructVector::iterator i=gIR->structs.begin(); i!=gIR->structs.end(); ++i)
                {
                    if (t == i->type)
                    {
                        return llvm::PointerType::get(i->recty.get());
                    }
                }
            }

            // forward declaration
            TypeClass* tc = (TypeClass*)t;
            assert(tc->sym);
            tc->sym->toObjFile();
        }
        return llvm::PointerType::get(t->llvmType);
    }

    // functions
    case Tfunction:
    {
        if (t->llvmType == 0) {
            return DtoFunctionType(t,NULL);
        }
        else {
            return t->llvmType;
        }
    }

    // delegates
    case Tdelegate:
    {
        if (t->llvmType == 0) {
            return DtoDelegateType(t);
        }
        else {
            return t->llvmType;
        }
    }

    // typedefs
    // enum
    case Ttypedef:
    case Tenum:
    {
        Type* bt = t->toBasetype();
        assert(bt);
        return DtoType(bt);
    }

    default:
        printf("trying to convert unknown type with value %d\n", t->ty);
        assert(0);
    }
    return 0;
}

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

const llvm::FunctionType* DtoFunctionType(Type* type, const llvm::Type* thistype, bool ismain)
{
    TypeFunction* f = (TypeFunction*)type;
    assert(f != 0);

    bool typesafeVararg = false;
    if (f->linkage == LINKd && f->varargs == 1) {
        typesafeVararg = true;
    }

    // return value type
    const llvm::Type* rettype;
    const llvm::Type* actualRettype;
    Type* rt = f->next;
    bool retinptr = false;
    bool usesthis = false;

    if (ismain) {
        rettype = llvm::Type::Int32Ty;
        actualRettype = rettype;
    }
    else {
        assert(rt);
        if (DtoIsPassedByRef(rt)) {
            rettype = llvm::PointerType::get(DtoType(rt));
            actualRettype = llvm::Type::VoidTy;
            f->llvmRetInPtr = retinptr = true;
        }
        else {
            rettype = DtoType(rt);
            actualRettype = rettype;
        }
    }

    // parameter types
    std::vector<const llvm::Type*> paramvec;

    if (retinptr) {
        Logger::cout() << "returning through pointer parameter: " << *rettype << '\n';
        paramvec.push_back(rettype);
    }

    if (thistype) {
        paramvec.push_back(thistype);
        usesthis = true;
    }

    if (typesafeVararg) {
        ClassDeclaration* ti = Type::typeinfo;
        if (!ti->llvmInitZ)
            ti->toObjFile();
        assert(ti->llvmInitZ);
        std::vector<const llvm::Type*> types;
        types.push_back(DtoSize_t());
        types.push_back(llvm::PointerType::get(llvm::PointerType::get(ti->llvmInitZ->getType())));
        const llvm::Type* t1 = llvm::StructType::get(types);
        paramvec.push_back(llvm::PointerType::get(t1));
        paramvec.push_back(llvm::PointerType::get(llvm::Type::Int8Ty));
    }

    size_t n = Argument::dim(f->parameters);

    for (int i=0; i < n; ++i) {
        Argument* arg = Argument::getNth(f->parameters, i);
        // ensure scalar
        Type* argT = DtoDType(arg->type);
        assert(argT);

        if ((arg->storageClass & STCref) || (arg->storageClass & STCout)) {
            //assert(arg->vardecl);
            //arg->vardecl->refparam = true;
        }
        else
            arg->llvmCopy = true;

        const llvm::Type* at = DtoType(argT);
        if (llvm::isa<llvm::StructType>(at)) {
            Logger::println("struct param");
            paramvec.push_back(llvm::PointerType::get(at));
        }
        else if (llvm::isa<llvm::ArrayType>(at)) {
            Logger::println("sarray param");
            assert(argT->ty == Tsarray);
            //paramvec.push_back(llvm::PointerType::get(at->getContainedType(0)));
            paramvec.push_back(llvm::PointerType::get(at));
        }
        else if (llvm::isa<llvm::OpaqueType>(at)) {
            Logger::println("opaque param");
            if (argT->ty == Tstruct || argT->ty == Tclass)
                paramvec.push_back(llvm::PointerType::get(at));
            else
            assert(0);
        }
        /*if (llvm::isa<llvm::StructType>(at) || argT->ty == Tstruct || argT->ty == Tsarray) {
            paramvec.push_back(llvm::PointerType::get(at));
        }*/
        else {
            if (!arg->llvmCopy) {
                Logger::println("ref param");
                at = llvm::PointerType::get(at);
            }
            else {
                Logger::println("in param");
            }
            paramvec.push_back(at);
        }
    }

    // construct function type
    bool isvararg = !typesafeVararg && f->varargs;
    llvm::FunctionType* functype = llvm::FunctionType::get(actualRettype, paramvec, isvararg);

    f->llvmRetInPtr = retinptr;
    f->llvmUsesThis = usesthis;
    return functype;
}

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

static const llvm::FunctionType* DtoVaFunctionType(FuncDeclaration* fdecl)
{
    TypeFunction* f = (TypeFunction*)fdecl->type;
    assert(f != 0);

    const llvm::PointerType* i8pty = llvm::PointerType::get(llvm::Type::Int8Ty);
    std::vector<const llvm::Type*> args;

    if (fdecl->llvmInternal == LLVMva_start) {
        args.push_back(i8pty);
    }
    else if (fdecl->llvmInternal == LLVMva_intrinsic) {
        size_t n = Argument::dim(f->parameters);
        for (size_t i=0; i<n; ++i) {
            args.push_back(i8pty);
        }
    }
    else
    assert(0);

    const llvm::FunctionType* fty = llvm::FunctionType::get(llvm::Type::VoidTy, args, false);
    f->llvmType = fty;
    return fty;
}

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

const llvm::FunctionType* DtoFunctionType(FuncDeclaration* fdecl)
{
    if ((fdecl->llvmInternal == LLVMva_start) || (fdecl->llvmInternal == LLVMva_intrinsic)) {
        return DtoVaFunctionType(fdecl);
    }

    // type has already been resolved
    if (fdecl->type->llvmType != 0) {
        return llvm::cast<llvm::FunctionType>(fdecl->type->llvmType);
    }

    const llvm::Type* thisty = NULL;
    if (fdecl->needThis()) {
        if (AggregateDeclaration* ad = fdecl->isMember()) {
            Logger::print("isMember = this is: %s\n", ad->type->toChars());
            thisty = DtoType(ad->type);
            Logger::cout() << "this llvm type: " << *thisty << '\n';
            if (llvm::isa<llvm::StructType>(thisty) || thisty == gIR->topstruct().recty.get())
                thisty = llvm::PointerType::get(thisty);
        }
        else
        assert(0);
    }
    else if (fdecl->isNested()) {
        thisty = llvm::PointerType::get(llvm::Type::Int8Ty);
    }

    const llvm::FunctionType* functype = DtoFunctionType(fdecl->type, thisty, fdecl->isMain());
    fdecl->type->llvmType = functype;
    return functype;
}

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

const llvm::StructType* DtoDelegateType(Type* t)
{
    const llvm::Type* i8ptr = llvm::PointerType::get(llvm::Type::Int8Ty);
    const llvm::Type* func = DtoFunctionType(t->next, i8ptr);
    const llvm::Type* funcptr = llvm::PointerType::get(func);

    std::vector<const llvm::Type*> types;
    types.push_back(i8ptr);
    types.push_back(funcptr);
    return llvm::StructType::get(types);
}

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

const llvm::Type* DtoStructType(Type* t)
{
    assert(0);
    std::vector<const llvm::Type*> types;
    return llvm::StructType::get(types);
}


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

static llvm::Function* LLVM_DeclareMemIntrinsic(const char* name, int bits, bool set=false)
{
    assert(bits == 32 || bits == 64);
    const llvm::Type* int8ty =    (const llvm::Type*)llvm::Type::Int8Ty;
    const llvm::Type* int32ty =   (const llvm::Type*)llvm::Type::Int32Ty;
    const llvm::Type* int64ty =   (const llvm::Type*)llvm::Type::Int64Ty;
    const llvm::Type* int8ptrty = (const llvm::Type*)llvm::PointerType::get(llvm::Type::Int8Ty);
    const llvm::Type* voidty =    (const llvm::Type*)llvm::Type::VoidTy;

    assert(gIR);
    assert(gIR->module);

    // parameter types
    std::vector<const llvm::Type*> pvec;
    pvec.push_back(int8ptrty);
    pvec.push_back(set?int8ty:int8ptrty);
    pvec.push_back(bits==32?int32ty:int64ty);
    pvec.push_back(int32ty);
    llvm::FunctionType* functype = llvm::FunctionType::get(voidty, pvec, false);
    return new llvm::Function(functype, llvm::GlobalValue::ExternalLinkage, name, gIR->module);
}

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

// llvm.memset.i32
llvm::Function* LLVM_DeclareMemSet32()
{
    static llvm::Function* _func = 0;
    if (_func == 0) {
        _func = LLVM_DeclareMemIntrinsic("llvm.memset.i32", 32, true);
    }
    return _func;
}

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

llvm::Function* LLVM_DeclareMemSet64()
{
    static llvm::Function* _func = 0;
    if (_func == 0) {
        _func = LLVM_DeclareMemIntrinsic("llvm.memset.i64", 64, true);
    }
    return _func;
}

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

// llvm.memcpy.i32
llvm::Function* LLVM_DeclareMemCpy32()
{
    static llvm::Function* _func = 0;
    if (_func == 0) {
        _func = LLVM_DeclareMemIntrinsic("llvm.memcpy.i32", 32);
    }
    return _func;
}

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

// llvm.memcpy.i64
llvm::Function* LLVM_DeclareMemCpy64()
{
    static llvm::Function* _func = 0;
    if (_func == 0) {
        _func = LLVM_DeclareMemIntrinsic("llvm.memcpy.i64", 64);
    }
    return _func;
}

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

llvm::Value* DtoStructZeroInit(llvm::Value* v)
{
    assert(gIR);
    uint64_t n = gTargetData->getTypeSize(v->getType()->getContainedType(0));
    //llvm::Type* sarrty = llvm::PointerType::get(llvm::ArrayType::get(llvm::Type::Int8Ty, n));
    llvm::Type* sarrty = llvm::PointerType::get(llvm::Type::Int8Ty);

    llvm::Value* sarr = new llvm::BitCastInst(v,sarrty,"tmp",gIR->scopebb());

    llvm::Function* fn = LLVM_DeclareMemSet32();
    std::vector<llvm::Value*> llargs;
    llargs.resize(4);
    llargs[0] = sarr;
    llargs[1] = llvm::ConstantInt::get(llvm::Type::Int8Ty, 0, false);
    llargs[2] = llvm::ConstantInt::get(llvm::Type::Int32Ty, n, false);
    llargs[3] = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0, false);

    llvm::Value* ret = new llvm::CallInst(fn, llargs.begin(), llargs.end(), "", gIR->scopebb());

    return ret;
}

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

llvm::Value* DtoStructCopy(llvm::Value* dst, llvm::Value* src)
{
    Logger::cout() << "dst = " << *dst << " src = " << *src << '\n';
    assert(dst->getType() == src->getType());
    assert(gIR);

    uint64_t n = gTargetData->getTypeSize(dst->getType()->getContainedType(0));
    //llvm::Type* sarrty = llvm::PointerType::get(llvm::ArrayType::get(llvm::Type::Int8Ty, n));
    llvm::Type* arrty = llvm::PointerType::get(llvm::Type::Int8Ty);

    llvm::Value* dstarr = new llvm::BitCastInst(dst,arrty,"tmp",gIR->scopebb());
    llvm::Value* srcarr = new llvm::BitCastInst(src,arrty,"tmp",gIR->scopebb());

    llvm::Function* fn = LLVM_DeclareMemCpy32();
    std::vector<llvm::Value*> llargs;
    llargs.resize(4);
    llargs[0] = dstarr;
    llargs[1] = srcarr;
    llargs[2] = llvm::ConstantInt::get(llvm::Type::Int32Ty, n, false);
    llargs[3] = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0, false);

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

//////////////////////////////////////////////////////////////////////////////////////////
llvm::Constant* DtoConstStructInitializer(StructInitializer* si)
{
    llvm::StructType* structtype = llvm::cast<llvm::StructType>(si->ad->llvmType);
    size_t n = structtype->getNumElements();

    assert(si->value.dim == si->vars.dim);

    std::vector<llvm::Constant*> inits;
    inits.resize(n, NULL);
    for (int i = 0; i < si->value.dim; ++i)
    {
        Initializer* ini = (Initializer*)si->value.data[i];
        assert(ini);

        VarDeclaration* vd = (VarDeclaration*)si->vars.data[i];
        Type* vdtype = DtoDType(vd->type);
        assert(vd);
        Logger::println("vars[%d] = %s", i, vd->toChars());

        llvm::Constant* v = 0;

        assert(vd->llvmFieldIndex >= 0);
        unsigned idx = vd->llvmFieldIndex;

        if (ExpInitializer* ex = ini->isExpInitializer())
        {
            v = ex->exp->toConstElem(gIR);
        }
        else if (StructInitializer* si = ini->isStructInitializer())
        {
            v = DtoConstStructInitializer(si);
        }
        else if (ArrayInitializer* ai = ini->isArrayInitializer())
        {
            v = DtoConstArrayInitializer(ai);
        }
        else if (ini->isVoidInitializer())
        {
            v = llvm::UndefValue::get(structtype->getElementType(idx));
        }
        else
        assert(v);

        inits[idx] = v;
        Logger::cout() << "init[" << idx << "] = " << *v << '\n';
    }

    // fill out nulls
    assert(si->ad->llvmInitZ);
    if (si->ad->llvmInitZ->isNullValue())
    {
        for (int i = 0; i < n; ++i)
        {
            if (inits[i] == 0)
            {
                inits[i] = llvm::Constant::getNullValue(structtype->getElementType(i));
            }
        }
    }
    else
    {
        for (int i = 0; i < n; ++i)
        {
            if (inits[i] == 0)
            {
                inits[i] = si->ad->llvmInitZ->getOperand(i);
            }
        }
    }

    return llvm::ConstantStruct::get(structtype, inits);
}



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

llvm::Value* DtoNullDelegate(llvm::Value* v)
{
    assert(gIR);
    d_uns64 n = (global.params.is64bit) ? 16 : 8;

    llvm::Type* i8p_ty = llvm::PointerType::get(llvm::Type::Int8Ty);

    llvm::Value* arr = new llvm::BitCastInst(v,i8p_ty,"tmp",gIR->scopebb());

    llvm::Function* fn = LLVM_DeclareMemSet32();
    std::vector<llvm::Value*> llargs;
    llargs.resize(4);
    llargs[0] = arr;
    llargs[1] = llvm::ConstantInt::get(llvm::Type::Int8Ty, 0, false);
    llargs[2] = llvm::ConstantInt::get(llvm::Type::Int32Ty, n, false);
    llargs[3] = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0, false);

    llvm::Value* ret = new llvm::CallInst(fn, llargs.begin(), llargs.end(), "", gIR->scopebb());

    return ret;
}

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

llvm::Value* DtoDelegateCopy(llvm::Value* dst, llvm::Value* src)
{
    assert(dst->getType() == src->getType());
    assert(gIR);

    d_uns64 n = (global.params.is64bit) ? 16 : 8;

    llvm::Type* arrty = llvm::PointerType::get(llvm::Type::Int8Ty);

    llvm::Value* dstarr = new llvm::BitCastInst(dst,arrty,"tmp",gIR->scopebb());
    llvm::Value* srcarr = new llvm::BitCastInst(src,arrty,"tmp",gIR->scopebb());

    llvm::Function* fn = LLVM_DeclareMemCpy32();
    std::vector<llvm::Value*> llargs;
    llargs.resize(4);
    llargs[0] = dstarr;
    llargs[1] = srcarr;
    llargs[2] = llvm::ConstantInt::get(llvm::Type::Int32Ty, n, false);
    llargs[3] = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0, false);

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

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

llvm::Value* DtoCompareDelegate(TOK op, llvm::Value* lhs, llvm::Value* rhs)
{
    llvm::ICmpInst::Predicate pred = (op == TOKequal) ? llvm::ICmpInst::ICMP_EQ : llvm::ICmpInst::ICMP_NE;
    llvm::Value* l = gIR->ir->CreateLoad(DtoGEPi(lhs,0,0,"tmp"),"tmp");
    llvm::Value* r = gIR->ir->CreateLoad(DtoGEPi(rhs,0,0,"tmp"),"tmp");
    llvm::Value* b1 = gIR->ir->CreateICmp(pred,l,r,"tmp");
    l = gIR->ir->CreateLoad(DtoGEPi(lhs,0,1,"tmp"),"tmp");
    r = gIR->ir->CreateLoad(DtoGEPi(rhs,0,1,"tmp"),"tmp");
    llvm::Value* b2 = gIR->ir->CreateICmp(pred,l,r,"tmp");
    llvm::Value* b = gIR->ir->CreateAnd(b1,b2,"tmp");
    if (op == TOKnotequal)
        return gIR->ir->CreateNot(b,"tmp");
    return b;
}

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

llvm::GlobalValue::LinkageTypes DtoLinkage(PROT prot, uint stc)
{
    switch(prot)
    {
    case PROTprivate:
        return llvm::GlobalValue::InternalLinkage;

    case PROTpublic:
    case PROTpackage:
    case PROTprotected:
    case PROTexport:
        return llvm::GlobalValue::ExternalLinkage;

    case PROTundefined:
    case PROTnone:
        assert(0 && "Unsupported linkage type");
    }
    return llvm::GlobalValue::ExternalLinkage;

/*      ExternalLinkage = 0, LinkOnceLinkage, WeakLinkage, AppendingLinkage,
  InternalLinkage, DLLImportLinkage, DLLExportLinkage, ExternalWeakLinkage,
  GhostLinkage */
}

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

unsigned DtoCallingConv(LINK l)
{
    if (l == LINKc)
        return llvm::CallingConv::C;
    else if (l == LINKd || l == LINKdefault)
        return llvm::CallingConv::Fast;
    else if (l == LINKwindows)
        return llvm::CallingConv::X86_StdCall;
    else
        assert(0 && "Unsupported calling convention");
}

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

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

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

llvm::Value* DtoBoolean(llvm::Value* val)
{
    const llvm::Type* t = val->getType();
    if (t->isInteger())
    {
        if (t == llvm::Type::Int1Ty)
            return val;
        else {
            llvm::Value* zero = llvm::ConstantInt::get(t, 0, false);
            return new llvm::ICmpInst(llvm::ICmpInst::ICMP_NE, val, zero, "tmp", gIR->scopebb());
        }
    }
    else if (llvm::isa<llvm::PointerType>(t)) {
        const llvm::Type* st = DtoSize_t();
        llvm::Value* ptrasint = new llvm::PtrToIntInst(val,st,"tmp",gIR->scopebb());
        llvm::Value* zero = llvm::ConstantInt::get(st, 0, false);
        return new llvm::ICmpInst(llvm::ICmpInst::ICMP_NE, ptrasint, zero, "tmp", gIR->scopebb());
    }
    else
    {
        Logger::cout() << *t << '\n';
    }
    assert(0);
    return 0;
}

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

const llvm::Type* DtoSize_t()
{
    if (global.params.is64bit)
    return llvm::Type::Int64Ty;
    else
    return llvm::Type::Int32Ty;
}

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

void DtoMain()
{
    // emit main function llvm style
    // int main(int argc, char**argv, char**env);

    assert(gIR != 0);
    IRState& ir = *gIR;

    assert(ir.emitMain && ir.mainFunc);

    // parameter types
    std::vector<const llvm::Type*> pvec;
    pvec.push_back((const llvm::Type*)llvm::Type::Int32Ty);
    const llvm::Type* chPtrType = (const llvm::Type*)llvm::PointerType::get(llvm::Type::Int8Ty);
    pvec.push_back((const llvm::Type*)llvm::PointerType::get(chPtrType));
    pvec.push_back((const llvm::Type*)llvm::PointerType::get(chPtrType));
    const llvm::Type* rettype = (const llvm::Type*)llvm::Type::Int32Ty;

    llvm::FunctionType* functype = llvm::FunctionType::get(rettype, pvec, false);
    llvm::Function* func = new llvm::Function(functype,llvm::GlobalValue::ExternalLinkage,"main",ir.module);

    llvm::BasicBlock* bb = new llvm::BasicBlock("entry",func);

    // call static ctors
    llvm::Function* fn = LLVM_D_GetRuntimeFunction(ir.module,"_d_run_module_ctors");
    new llvm::CallInst(fn,"",bb);

    // call user main function
    llvm::CallInst* call = new llvm::CallInst(ir.mainFunc,"ret",bb);
    call->setCallingConv(ir.mainFunc->getCallingConv());

    // call static dtors
    fn = LLVM_D_GetRuntimeFunction(ir.module,"_d_run_module_dtors");
    new llvm::CallInst(fn,"",bb);

    // return
    new llvm::ReturnInst(call,bb);
}

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

void DtoCallClassDtors(TypeClass* tc, llvm::Value* instance)
{
    Array* arr = &tc->sym->dtors;
    for (size_t i=0; i<arr->dim; i++)
    {
        FuncDeclaration* fd = (FuncDeclaration*)arr->data[i];
        assert(fd->llvmValue);
        new llvm::CallInst(fd->llvmValue, instance, "", gIR->scopebb());
    }
}

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

void DtoInitClass(TypeClass* tc, llvm::Value* dst)
{
    assert(gIR);

    assert(tc->llvmType);
    uint64_t size_t_size = gTargetData->getTypeSize(DtoSize_t());
    uint64_t n = gTargetData->getTypeSize(tc->llvmType) - size_t_size;

    // set vtable field
    llvm::Value* vtblvar = DtoGEPi(dst,0,0,"tmp",gIR->scopebb());
    assert(tc->sym->llvmVtbl);
    new llvm::StoreInst(tc->sym->llvmVtbl, vtblvar, gIR->scopebb());

    // copy the static initializer
    if (n > 0) {
        assert(tc->llvmInit);
        assert(dst->getType() == tc->llvmInit->getType());

        llvm::Type* arrty = llvm::PointerType::get(llvm::Type::Int8Ty);

        llvm::Value* dstarr = new llvm::BitCastInst(dst,arrty,"tmp",gIR->scopebb());
        dstarr = DtoGEPi(dstarr,size_t_size,"tmp",gIR->scopebb());

        llvm::Value* srcarr = new llvm::BitCastInst(tc->llvmInit,arrty,"tmp",gIR->scopebb());
        srcarr = DtoGEPi(srcarr,size_t_size,"tmp",gIR->scopebb());

        llvm::Function* fn = LLVM_DeclareMemCpy32();
        std::vector<llvm::Value*> llargs;
        llargs.resize(4);
        llargs[0] = dstarr;
        llargs[1] = srcarr;
        llargs[2] = llvm::ConstantInt::get(llvm::Type::Int32Ty, n, false);
        llargs[3] = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0, false);

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

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

llvm::Constant* DtoConstInitializer(Type* type, Initializer* init)
{
    llvm::Constant* _init = 0; // may return zero
    if (!init)
    {
        Logger::println("const default initializer for %s", type->toChars());
        _init = type->defaultInit()->toConstElem(gIR);
    }
    else if (ExpInitializer* ex = init->isExpInitializer())
    {
        Logger::println("const expression initializer");
        _init = ex->exp->toConstElem(gIR);
    }
    else if (StructInitializer* si = init->isStructInitializer())
    {
        Logger::println("const struct initializer");
        _init = DtoConstStructInitializer(si);
    }
    else if (ArrayInitializer* ai = init->isArrayInitializer())
    {
        Logger::println("const array initializer");
        _init = DtoConstArrayInitializer(ai);
    }
    else if (init->isVoidInitializer())
    {
        Logger::println("const void initializer");
        const llvm::Type* ty = DtoType(type);
        _init = llvm::Constant::getNullValue(ty);
    }
    else {
        Logger::println("unsupported const initializer: %s", init->toChars());
    }
    return _init;
}

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

DValue* DtoInitializer(Initializer* init)
{
    if (ExpInitializer* ex = init->isExpInitializer())
    {
        Logger::println("expression initializer");
        return ex->exp->toElem(gIR);
    }
    else if (init->isVoidInitializer())
    {
        // do nothing
    }
    else {
        Logger::println("unsupported initializer: %s", init->toChars());
        assert(0);
    }
    return 0;
}

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

llvm::Value* DtoGEP(llvm::Value* ptr, llvm::Value* i0, llvm::Value* i1, const std::string& var, llvm::BasicBlock* bb)
{
    std::vector<llvm::Value*> v(2);
    v[0] = i0;
    v[1] = i1;
    Logger::cout() << "DtoGEP: " << *ptr << '\n';
    return new llvm::GetElementPtrInst(ptr, v.begin(), v.end(), var, bb?bb:gIR->scopebb());
}

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

llvm::Value* DtoGEP(llvm::Value* ptr, const std::vector<unsigned>& src, const std::string& var, llvm::BasicBlock* bb)
{
    size_t n = src.size();
    std::vector<llvm::Value*> dst(n);
    std::ostream& ostr = Logger::cout();
    ostr << "indices for '" << *ptr << "':";
    for (size_t i=0; i<n; ++i)
    {
        ostr << ' ' << i;
        dst[i] = llvm::ConstantInt::get(llvm::Type::Int32Ty, src[i], false);
    }
    ostr << '\n';
    return new llvm::GetElementPtrInst(ptr, dst.begin(), dst.end(), var, bb?bb:gIR->scopebb());
}

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

llvm::Value* DtoGEPi(llvm::Value* ptr, unsigned i, const std::string& var, llvm::BasicBlock* bb)
{
    return new llvm::GetElementPtrInst(ptr, llvm::ConstantInt::get(llvm::Type::Int32Ty, i, false), var, bb?bb:gIR->scopebb());
}

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

llvm::Value* DtoGEPi(llvm::Value* ptr, unsigned i0, unsigned i1, const std::string& var, llvm::BasicBlock* bb)
{
    std::vector<llvm::Value*> v(2);
    v[0] = llvm::ConstantInt::get(llvm::Type::Int32Ty, i0, false);
    v[1] = llvm::ConstantInt::get(llvm::Type::Int32Ty, i1, false);
    return new llvm::GetElementPtrInst(ptr, v.begin(), v.end(), var, bb?bb:gIR->scopebb());
}

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

static llvm::Function* DtoDeclareVaFunction(FuncDeclaration* fdecl)
{
    TypeFunction* f = (TypeFunction*)DtoDType(fdecl->type);
    const llvm::FunctionType* fty = DtoVaFunctionType(fdecl);
    llvm::Constant* fn = 0;

    if (fdecl->llvmInternal == LLVMva_start) {
        fn = gIR->module->getOrInsertFunction("llvm.va_start", fty);
        assert(fn);
    }
    else if (fdecl->llvmInternal == LLVMva_intrinsic) {
        fn = gIR->module->getOrInsertFunction(fdecl->llvmInternal1, fty);
        assert(fn);
    }
    else
    assert(0);

    llvm::Function* func = llvm::cast_or_null<llvm::Function>(fn);
    assert(func);
    assert(func->isIntrinsic());
    fdecl->llvmValue = func;
    return func;
}

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

llvm::Function* DtoDeclareFunction(FuncDeclaration* fdecl)
{
    if ((fdecl->llvmInternal == LLVMva_start) || (fdecl->llvmInternal == LLVMva_intrinsic)) {
        return DtoDeclareVaFunction(fdecl);
    }

    // mangled name
    char* mangled_name;
    if (fdecl->llvmInternal == LLVMintrinsic)
        mangled_name = fdecl->llvmInternal1;
    else
        mangled_name = fdecl->mangle();

    // unit test special handling
    if (fdecl->isUnitTestDeclaration())
    {
        assert(0 && "no unittests yet");
        /*const llvm::FunctionType* fnty = llvm::FunctionType::get(llvm::Type::VoidTy, std::vector<const llvm::Type*>(), false);
        // make the function
        llvm::Function* func = gIR->module->getFunction(mangled_name);
        if (func == 0)
            func = new llvm::Function(fnty,llvm::GlobalValue::InternalLinkage,mangled_name,gIR->module);
        func->setCallingConv(llvm::CallingConv::Fast);
        fdecl->llvmValue = func;
        return func;
        */
    }

    // regular function
    TypeFunction* f = (TypeFunction*)DtoDType(fdecl->type);
    assert(f != 0);

    if (fdecl->llvmValue != 0) {
        if (!llvm::isa<llvm::Function>(fdecl->llvmValue))
        {
            Logger::cout() << *fdecl->llvmValue << '\n';
            assert(0);
        }
        return llvm::cast<llvm::Function>(fdecl->llvmValue);
    }

    Logger::print("FuncDeclaration::toObjFile(%s): %s\n", fdecl->needThis()?"this":"static",fdecl->toChars());
    LOG_SCOPE;

    if (fdecl->llvmInternal == LLVMintrinsic && fdecl->fbody) {
        error("intrinsics cannot have function bodies");
        fatal();
    }

    // construct function
    const llvm::FunctionType* functype = (f->llvmType == 0) ? DtoFunctionType(fdecl) : llvm::cast<llvm::FunctionType>(f->llvmType);

    // make the function
    llvm::Function* func = gIR->module->getFunction(mangled_name);
    if (func == 0) {
        func = new llvm::Function(functype,DtoLinkage(fdecl->protection, fdecl->storage_class),mangled_name,gIR->module);
    }

    if (fdecl->llvmInternal != LLVMintrinsic)
        func->setCallingConv(DtoCallingConv(f->linkage));

    fdecl->llvmValue = func;
    f->llvmType = functype;
    assert(llvm::isa<llvm::FunctionType>(f->llvmType));

    if (fdecl->isMain()) {
        gIR->mainFunc = func;
    }

    // name parameters
    llvm::Function::arg_iterator iarg = func->arg_begin();
    int k = 0;
    if (f->llvmRetInPtr) {
        iarg->setName("retval");
        f->llvmRetArg = iarg;
        ++iarg;
    }
    if (f->llvmUsesThis) {
        iarg->setName("this");
        ++iarg;
    }
    int varargs = -1;
    if (f->linkage == LINKd && f->varargs == 1)
        varargs = 0;
    for (; iarg != func->arg_end(); ++iarg)
    {
        Argument* arg = Argument::getNth(f->parameters, k++);
        //arg->llvmValue = iarg;
        //Logger::println("identifier: '%s' %p\n", arg->ident->toChars(), arg->ident);
        if (arg && arg->ident != 0) {
            if (arg->vardecl) {
                arg->vardecl->llvmValue = iarg;
            }
            iarg->setName(arg->ident->toChars());
        }
        else if (!arg && varargs >= 0) {
            if (varargs == 0) {
                iarg->setName("_arguments");
                fdecl->llvmArguments = iarg;
            }
            else if (varargs == 1) {
                iarg->setName("_argptr");
                fdecl->llvmArgPtr = iarg;
            }
            else
            assert(0);
            varargs++;
        }
        else {
            iarg->setName("unnamed");
        }
    }

    Logger::cout() << "func decl: " << *func << '\n';

    return func;
}

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

llvm::Value* DtoRealloc(llvm::Value* ptr, const llvm::Type* ty)
{
    /*size_t sz = gTargetData->getTypeSize(ty);
    llvm::ConstantInt* n = llvm::ConstantInt::get(DtoSize_t(), sz, false);
    if (ptr == 0) {
        llvm::PointerType* i8pty = llvm::PointerType::get(llvm::Type::Int8Ty);
        ptr = llvm::ConstantPointerNull::get(i8pty);
    }
    return DtoRealloc(ptr, n);*/
    return NULL;
}

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

llvm::Value* DtoRealloc(llvm::Value* ptr, llvm::Value* n)
{
    assert(ptr);
    assert(n);

    llvm::Function* fn = LLVM_D_GetRuntimeFunction(gIR->module, "_d_realloc");
    assert(fn);

    llvm::Value* newptr = ptr;

    llvm::PointerType* i8pty = llvm::PointerType::get(llvm::Type::Int8Ty);
    if (ptr->getType() != i8pty) {
        newptr = new llvm::BitCastInst(ptr,i8pty,"tmp",gIR->scopebb());
    }

    std::vector<llvm::Value*> args;
    args.push_back(newptr);
    args.push_back(n);
    llvm::Value* ret = new llvm::CallInst(fn, args.begin(), args.end(), "tmprealloc", gIR->scopebb());

    return ret->getType() == ptr->getType() ? ret : new llvm::BitCastInst(ret,ptr->getType(),"tmp",gIR->scopebb());
}

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

void DtoAssert(llvm::Value* cond, llvm::Value* loc, llvm::Value* msg)
{
    assert(loc);
    std::vector<llvm::Value*> llargs;
    llargs.resize(3);
    llargs[0] = cond ? DtoBoolean(cond) : llvm::ConstantInt::getFalse();
    llargs[1] = loc;
    llargs[2] = msg ? msg : llvm::ConstantPointerNull::get(llvm::PointerType::get(llvm::Type::Int8Ty));

    llvm::Function* fn = LLVM_D_GetRuntimeFunction(gIR->module, "_d_assert");
    assert(fn);
    llvm::CallInst* call = new llvm::CallInst(fn, llargs.begin(), llargs.end(), "", gIR->scopebb());
    call->setCallingConv(llvm::CallingConv::C);
}

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

llvm::Value* DtoArgument(const llvm::Type* paramtype, Argument* fnarg, Expression* argexp)
{
    llvm::Value* retval = 0;

    bool haslvals = !gIR->exps.empty();
    if (haslvals)
        gIR->exps.push_back(IRExp(NULL,NULL,NULL));

    DValue* arg = argexp->toElem(gIR);

    if (haslvals)
        gIR->exps.pop_back();

    if (arg->inPlace()) {
        retval = arg->getRVal();
        return retval;
    }

    Type* realtype = DtoDType(argexp->type);
    TY argty = realtype->ty;
    if (DtoIsPassedByRef(realtype)) {
        if (!fnarg || !fnarg->llvmCopy) {
            if (DSliceValue* sv = arg->isSlice()) {
                retval = new llvm::AllocaInst(DtoType(realtype), "tmpparam", gIR->topallocapoint());
                DtoSetArray(retval, DtoArrayLen(sv), DtoArrayPtr(sv));
            }
            else {
                retval = arg->getRVal();
            }
        }
        else {
            llvm::Value* allocaInst = 0;
            llvm::BasicBlock* entryblock = &gIR->topfunc()->front();
            //const llvm::PointerType* pty = llvm::cast<llvm::PointerType>(arg->mem->getType());
            const llvm::Type* realtypell = DtoType(realtype);
            const llvm::PointerType* pty = llvm::PointerType::get(realtypell);
            if (argty == Tstruct) {
                allocaInst = new llvm::AllocaInst(pty->getElementType(), "tmpparam", gIR->topallocapoint());
                DValue* dst = new DVarValue(realtype, allocaInst, true);
                DtoAssign(dst,arg);
                delete dst;
            }
            else if (argty == Tdelegate) {
                allocaInst = new llvm::AllocaInst(pty->getElementType(), "tmpparam", gIR->topallocapoint());
                DValue* dst = new DVarValue(realtype, allocaInst, true);
                DtoAssign(dst,arg);
                delete dst;
            }
            else if (argty == Tarray) {
                if (arg->isSlice()) {
                    allocaInst = new llvm::AllocaInst(realtypell, "tmpparam", gIR->topallocapoint());
                }
                else {
                    allocaInst = new llvm::AllocaInst(pty->getElementType(), "tmpparam", gIR->topallocapoint());
                }
            }
            else
            assert(0);

            DValue* dst = new DVarValue(realtype, allocaInst, true);
            DtoAssign(dst,arg);
            delete dst;

            retval = allocaInst;
        }
    }
    else if (!fnarg || fnarg->llvmCopy) {
        Logger::println("regular arg");
        if (DSliceValue* sl = arg->isSlice()) {
            if (sl->ptr) Logger::cout() << "ptr = " << *sl->ptr << '\n';
            if (sl->len) Logger::cout() << "len = " << *sl->len << '\n';
            assert(0);
        }
        else {
            retval = arg->getRVal();
        }
    }
    else {
        Logger::println("as ptr arg");
        retval = arg->getLVal();
        if (paramtype && retval->getType() != paramtype)
        {
            assert(0);
            /*assert(retval->getType() == paramtype->getContainedType(0));
            new llvm::StoreInst(retval, arg->getLVal(), gIR->scopebb());
            retval = arg->getLVal();*/
        }
    }

    if (fnarg && paramtype && retval->getType() != paramtype) {
        // this is unfortunately needed with the way SymOffExp is overused
        // and static arrays can end up being a pointer to their element type
        if (arg->isField()) {
            retval = gIR->ir->CreateBitCast(retval, paramtype, "tmp");
        }
        else {
            Logger::cout() << "got '" << *retval->getType() << "' expected '" << *paramtype << "'\n";
            assert(0 && "parameter type that was actually passed is invalid");
        }
    }

    delete arg;

    return retval;
}

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

llvm::Value* DtoNestedVariable(VarDeclaration* vd)
{
    FuncDeclaration* fd = vd->toParent()->isFuncDeclaration();
    assert(fd != NULL);

    IRFunction* fcur = &gIR->func();
    FuncDeclaration* f = fcur->decl;

    // on this stack
    if (fd == f) {
        llvm::Value* v = DtoGEPi(vd->llvmValue,0,unsigned(vd->llvmNestedIndex),"tmp");
        if (vd->isParameter() && (vd->isRef() || vd->isOut() || DtoIsPassedByRef(vd->type))) {
            Logger::cout() << "1267 loading: " << *v << '\n';
            v = gIR->ir->CreateLoad(v,"tmp");
        }
        return v;
    }

    // on a caller stack
    llvm::Value* ptr = f->llvmThisVar;
    assert(ptr);

    f = f->toParent()->isFuncDeclaration();
    assert(f);
    assert(f->llvmNested);
    const llvm::Type* nesttype = f->llvmNested->getType();
    assert(nesttype);

    ptr = gIR->ir->CreateBitCast(ptr, nesttype, "tmp");

    Logger::cout() << "nested var reference:" << '\n' << *ptr << *nesttype << '\n';

    while (f) {
        if (fd == f) {
            llvm::Value* v = DtoGEPi(ptr,0,vd->llvmNestedIndex,"tmp");
            if (vd->isParameter() && (vd->isRef() || vd->isOut() || DtoIsPassedByRef(vd->type))) {
                Logger::cout() << "1291 loading: " << *v << '\n';
                v = gIR->ir->CreateLoad(v,"tmp");
            }
            return v;
        }
        else {
            ptr = DtoGEPi(ptr,0,0,"tmp");
            ptr = gIR->ir->CreateLoad(ptr,"tmp");
        }
        f = f->toParent()->isFuncDeclaration();
    }

    assert(0 && "nested var not found");
    return NULL;
}

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

void DtoAssign(DValue* lhs, DValue* rhs)
{
    Type* t = DtoDType(lhs->getType());
    Type* t2 = DtoDType(rhs->getType());

    if (t->ty == Tstruct) {
        if (t2 != t) {
            // TODO: fix this, use 'rhs' for something
            DtoStructZeroInit(lhs->getLVal());
        }
        else if (!rhs->inPlace()) {
            DtoStructCopy(lhs->getLVal(),rhs->getRVal());
        }
    }
    else if (t->ty == Tarray) {
        // lhs is slice
        if (DSliceValue* s = lhs->isSlice()) {
            if (DSliceValue* s2 = rhs->isSlice()) {
                DtoArrayCopy(s, s2);
            }
            else if (t->next == t2) {
                if (s->len)
                    DtoArrayInit(s->ptr, s->len, rhs->getRVal());
                else
                    DtoArrayInit(s->ptr, rhs->getRVal());
            }
            else
            assert(rhs->inPlace());
        }
        // rhs is slice
        else if (DSliceValue* s = rhs->isSlice()) {
            DtoSetArray(lhs->getLVal(),s->len,s->ptr);
        }
        // null
        else if (rhs->isNull()) {
            DtoNullArray(lhs->getLVal());
        }
        // reference assignment
        else {
            DtoArrayAssign(lhs->getLVal(), rhs->getRVal());
        }
    }
    else if (t->ty == Tsarray) {
        DtoStaticArrayCopy(lhs->getLVal(), rhs->getRVal());
    }
    else if (t->ty == Tdelegate) {
        if (rhs->isNull())
            DtoNullDelegate(lhs->getLVal());
        else if (!rhs->inPlace())
            DtoDelegateCopy(lhs->getLVal(), rhs->getRVal());
    }
    else if (t->ty == Tclass) {
        assert(t2->ty == Tclass);
        // assignment to this in constructor special case
        if (lhs->isThis()) {
            llvm::Value* tmp = rhs->getRVal();
            FuncDeclaration* fdecl = gIR->func().decl;
            // respecify the this param
            if (!llvm::isa<llvm::AllocaInst>(fdecl->llvmThisVar))
                fdecl->llvmThisVar = new llvm::AllocaInst(tmp->getType(), "newthis", gIR->topallocapoint());
            DtoStore(tmp, fdecl->llvmThisVar);
        }
        // regular class ref -> class ref assignment
        else {
            DtoStore(rhs->getRVal(), lhs->getLVal());
        }
    }
    else {
        llvm::Value* r = rhs->getRVal();
        llvm::Value* l = lhs->getLVal();
        Logger::cout() << "assign\nlhs: " << *l << "rhs: " << *r << '\n';
        gIR->ir->CreateStore(r, l);
    }
}

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

llvm::ConstantInt* DtoConstSize_t(size_t i)
{
    return llvm::ConstantInt::get(DtoSize_t(), i, false);
}
llvm::ConstantInt* DtoConstUint(unsigned i)
{
    return llvm::ConstantInt::get(llvm::Type::Int32Ty, i, false);
}
llvm::ConstantInt* DtoConstInt(int i)
{
    return llvm::ConstantInt::get(llvm::Type::Int32Ty, i, true);
}
llvm::Constant* DtoConstBool(bool b)
{
    return llvm::ConstantInt::get(llvm::Type::Int1Ty, b, false);
}

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

llvm::Constant* DtoConstString(const char* str)
{
    std::string s(str);
    llvm::Constant* init = llvm::ConstantArray::get(s, true);
    llvm::GlobalVariable* gvar = new llvm::GlobalVariable(
        init->getType(), true,llvm::GlobalValue::InternalLinkage, init, "stringliteral", gIR->module);
    llvm::Constant* idxs[2] = { DtoConstUint(0), DtoConstUint(0) };
    return DtoConstSlice(
        DtoConstSize_t(s.length()),
        llvm::ConstantExpr::getGetElementPtr(gvar,idxs,2)
    );
}
llvm::Constant* DtoConstStringPtr(const char* str, const char* section)
{
    std::string s(str);
    llvm::Constant* init = llvm::ConstantArray::get(s, true);
    llvm::GlobalVariable* gvar = new llvm::GlobalVariable(
        init->getType(), true,llvm::GlobalValue::InternalLinkage, init, "stringliteral", gIR->module);
    if (section) gvar->setSection(section);
    llvm::Constant* idxs[2] = { DtoConstUint(0), DtoConstUint(0) };
    return llvm::ConstantExpr::getGetElementPtr(gvar,idxs,2);
}

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

void DtoMemCpy(llvm::Value* dst, llvm::Value* src, llvm::Value* nbytes)
{
    assert(dst->getType() == src->getType());

    llvm::Type* arrty = llvm::PointerType::get(llvm::Type::Int8Ty);
    llvm::Value *dstarr, *srcarr;
    if (dst->getType() == arrty)
    {
        dstarr = dst;
        srcarr = src;
    }
    else
    {
        dstarr = new llvm::BitCastInst(dst,arrty,"tmp",gIR->scopebb());
        srcarr = new llvm::BitCastInst(src,arrty,"tmp",gIR->scopebb());
    }

    llvm::Function* fn = (global.params.is64bit) ? LLVM_DeclareMemCpy64() : LLVM_DeclareMemCpy32();
    std::vector<llvm::Value*> llargs;
    llargs.resize(4);
    llargs[0] = dstarr;
    llargs[1] = srcarr;
    llargs[2] = nbytes;
    llargs[3] = llvm::ConstantInt::get(llvm::Type::Int32Ty, 0, false);

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

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

llvm::Value* DtoLoad(llvm::Value* src)
{
    return gIR->ir->CreateLoad(src,"tmp");
}

void DtoStore(llvm::Value* src, llvm::Value* dst)
{
    gIR->ir->CreateStore(src,dst);
}

bool DtoCanLoad(llvm::Value* ptr)
{
    if (llvm::isa<llvm::PointerType>(ptr->getType())) {
        return ptr->getType()->getContainedType(0)->isFirstClassType();
    }
    return false;
}

llvm::Value* DtoBitCast(llvm::Value* v, const llvm::Type* t)
{
    return gIR->ir->CreateBitCast(v, t, "tmp");
}

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

llvm::Value* DtoIndexStruct(llvm::Value* ptr, StructDeclaration* sd, Type* t, unsigned os, std::vector<unsigned>& idxs)
{
    Logger::println("checking for offset %u type %s:", os, t->toChars());
    LOG_SCOPE;

    if (idxs.empty())
        idxs.push_back(0);

    const llvm::Type* llt = llvm::PointerType::get(DtoType(t));

    for (unsigned i=0; i<sd->fields.dim; ++i) {
        VarDeclaration* vd = (VarDeclaration*)sd->fields.data[i];
        Type* vdtype = DtoDType(vd->type);
        Logger::println("found %u type %s", vd->offset, vdtype->toChars());
        assert(vd->llvmFieldIndex >= 0);
        if (os == vd->offset && vdtype == t) {
            idxs.push_back(vd->llvmFieldIndex);
            ptr = DtoGEP(ptr, idxs, "tmp");
            if (ptr->getType() != llt)
                ptr = gIR->ir->CreateBitCast(ptr, llt, "tmp");
            if (vd->llvmFieldIndexOffset)
                ptr = new llvm::GetElementPtrInst(ptr, DtoConstUint(vd->llvmFieldIndexOffset), "tmp", gIR->scopebb());
            return ptr;
        }
        else if (vdtype->ty == Tstruct && (vd->offset + vdtype->size()) > os) {
            TypeStruct* ts = (TypeStruct*)vdtype;
            StructDeclaration* ssd = ts->sym;
            idxs.push_back(vd->llvmFieldIndex);
            if (vd->llvmFieldIndexOffset) {
                Logger::println("has union field offset");
                ptr = DtoGEP(ptr, idxs, "tmp");
                if (ptr->getType() != llt)
                    ptr = gIR->ir->CreateBitCast(ptr, llt, "tmp");
                ptr = new llvm::GetElementPtrInst(ptr, DtoConstUint(vd->llvmFieldIndexOffset), "tmp", gIR->scopebb());
                std::vector<unsigned> tmp;
                return DtoIndexStruct(ptr, ssd, t, os-vd->offset, tmp);
            }
            else {
                const llvm::Type* sty = llvm::PointerType::get(DtoType(vd->type));
                if (ptr->getType() != sty) {
                    ptr = gIR->ir->CreateBitCast(ptr, sty, "tmp");
                    std::vector<unsigned> tmp;
                    return DtoIndexStruct(ptr, ssd, t, os-vd->offset, tmp);
                }
                else {
                    return DtoIndexStruct(ptr, ssd, t, os-vd->offset, idxs);
                }
            }
        }
    }

    size_t llt_sz = gTargetData->getTypeSize(llt->getContainedType(0));
    assert(os % llt_sz == 0);
    ptr = gIR->ir->CreateBitCast(ptr, llt, "tmp");
    return new llvm::GetElementPtrInst(ptr, DtoConstUint(os / llt_sz), "tmp", gIR->scopebb());
}

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

bool DtoIsTemplateInstance(Dsymbol* s)
{
    if (!s) return false;
    if (s->isTemplateInstance() && !s->isTemplateMixin())
        return true;
    else if (s->parent)
        return DtoIsTemplateInstance(s->parent);
    return false;
}