C++ LLValue类代码示例

void DtoInitClass(TypeClass* tc, LLValue* dst)
{
    tc->sym->codegen(Type::sir);

    uint64_t n = tc->sym->structsize - PTRSIZE * 2;

    // set vtable field seperately, this might give better optimization
    LLValue* tmp = DtoGEPi(dst,0,0,"vtbl");
    LLValue* val = DtoBitCast(tc->sym->ir.irStruct->getVtblSymbol(), tmp->getType()->getContainedType(0));
    DtoStore(val, tmp);

    // monitor always defaults to zero
    tmp = DtoGEPi(dst,0,1,"monitor");
    val = LLConstant::getNullValue(tmp->getType()->getContainedType(0));
    DtoStore(val, tmp);

    // done?
    if (n == 0)
        return;

    // copy the rest from the static initializer
    LLValue* dstarr = DtoGEPi(dst,0,2,"tmp");

    // init symbols might not have valid types
    LLValue* initsym = tc->sym->ir.irStruct->getInitSymbol();
    initsym = DtoBitCast(initsym, DtoType(tc));
    LLValue* srcarr = DtoGEPi(initsym,0,2,"tmp");

    DtoMemCpy(dstarr, srcarr, DtoConstSize_t(n));
}

LLValue* DtoBinFloatsEquals(Loc loc, DValue* lhs, DValue* rhs, TOK op)
{
    LLValue* res = 0;
#if DMDV2
    if (op == TOKequal) {
        res = gIR->ir->CreateFCmpOEQ(lhs->getRVal(), rhs->getRVal(), "tmp");
    } else if (op == TOKnotequal) {
        res = gIR->ir->CreateFCmpUNE(lhs->getRVal(), rhs->getRVal(), "tmp");
    } else {
        llvm::ICmpInst::Predicate cmpop;
        if (op == TOKidentity)
            cmpop = llvm::ICmpInst::ICMP_EQ;
        else
            cmpop = llvm::ICmpInst::ICMP_NE;

        LLValue* sz = DtoConstSize_t(getTypeStoreSize(DtoType(lhs->getType())));
        LLValue* val = DtoMemCmp(makeLValue(loc, lhs), makeLValue(loc, rhs), sz);
        res = gIR->ir->CreateICmp(cmpop, val, LLConstantInt::get(val->getType(), 0, false), "tmp");
    }
#else
    LLValue* lv = lhs->getRVal();
    LLValue* rv = rhs->getRVal();
    res = (op == TOKidentity || op == TOKequal) ?
                gIR->ir->CreateFCmpOEQ(lv, rv, "tmp") :
                gIR->ir->CreateFCmpUNE(lv, rv, "tmp");

#endif
    assert(res);
    return res;
}

void DtoInitClass(TypeClass* tc, LLValue* dst)
{
    DtoResolveClass(tc->sym);

    // Set vtable field. Doing this seperately might be optimized better.
    LLValue* tmp = DtoGEPi(dst, 0, 0, "vtbl");
    LLValue* val = DtoBitCast(getIrAggr(tc->sym)->getVtblSymbol(),
        tmp->getType()->getContainedType(0));
    DtoStore(val, tmp);

    // For D classes, set the monitor field to null.
    const bool isCPPclass = tc->sym->isCPPclass() ? true : false;
    if (!isCPPclass)
    {
        tmp = DtoGEPi(dst, 0, 1, "monitor");
        val = LLConstant::getNullValue(tmp->getType()->getContainedType(0));
        DtoStore(val, tmp);
    }

    // Copy the rest from the static initializer, if any.
    unsigned const firstDataIdx = isCPPclass ? 1 : 2;
    uint64_t const dataBytes = tc->sym->structsize - Target::ptrsize * firstDataIdx;
    if (dataBytes == 0)
        return;

    LLValue* dstarr = DtoGEPi(dst, 0, firstDataIdx);

    // init symbols might not have valid types
    LLValue* initsym = getIrAggr(tc->sym)->getInitSymbol();
    initsym = DtoBitCast(initsym, DtoType(tc));
    LLValue* srcarr = DtoGEPi(initsym, 0, firstDataIdx);

    DtoMemCpy(dstarr, srcarr, DtoConstSize_t(dataBytes));
}

DValue* DtoDynamicCastObject(DValue* val, Type* _to)
{
    // call:
    // Object _d_dynamic_cast(Object o, ClassInfo c)

    ClassDeclaration::object->codegen(Type::sir);
    ClassDeclaration::classinfo->codegen(Type::sir);

    llvm::Function* func = LLVM_D_GetRuntimeFunction(gIR->module, "_d_dynamic_cast");
    LLFunctionType* funcTy = func->getFunctionType();

    // Object o
    LLValue* obj = val->getRVal();
    obj = DtoBitCast(obj, funcTy->getParamType(0));
    assert(funcTy->getParamType(0) == obj->getType());

    // ClassInfo c
    TypeClass* to = static_cast<TypeClass*>(_to->toBasetype());
    to->sym->codegen(Type::sir);

    LLValue* cinfo = to->sym->ir.irAggr->getClassInfoSymbol();
    // unfortunately this is needed as the implementation of object differs somehow from the declaration
    // this could happen in user code as well :/
    cinfo = DtoBitCast(cinfo, funcTy->getParamType(1));
    assert(funcTy->getParamType(1) == cinfo->getType());

    // call it
    LLValue* ret = gIR->CreateCallOrInvoke2(func, obj, cinfo, "tmp").getInstruction();

    // cast return value
    ret = DtoBitCast(ret, DtoType(_to));

    return new DImValue(_to, ret);
}

static LLValue *call_string_switch_runtime(llvm::Value *table, Expression *e) {
  Type *dt = e->type->toBasetype();
  Type *dtnext = dt->nextOf()->toBasetype();
  TY ty = dtnext->ty;
  const char *fname;
  if (ty == Tchar) {
    fname = "_d_switch_string";
  } else if (ty == Twchar) {
    fname = "_d_switch_ustring";
  } else if (ty == Tdchar) {
    fname = "_d_switch_dstring";
  } else {
    llvm_unreachable("not char/wchar/dchar");
  }

  llvm::Function *fn = getRuntimeFunction(e->loc, gIR->module, fname);

  IF_LOG {
    Logger::cout() << *table->getType() << '\n';
    Logger::cout() << *fn->getFunctionType()->getParamType(0) << '\n';
  }
  assert(table->getType() == fn->getFunctionType()->getParamType(0));

  DValue *val = toElemDtor(e);
  LLValue *llval = val->getRVal();
  assert(llval->getType() == fn->getFunctionType()->getParamType(1));

  LLCallSite call = gIR->CreateCallOrInvoke(fn, table, llval);

  return call.getInstruction();
}

 LLValue *prepareVaStart(DLValue *ap) override {
   // Since the user only created a char* pointer (ap) on the stack before
   // invoking va_start, we first need to allocate the actual __va_list struct
   // and set `ap` to its address.
   LLValue *valistmem = DtoRawAlloca(getValistType(), 0, "__va_list_mem");
   DtoStore(valistmem,
            DtoBitCast(DtoLVal(ap), getPtrToType(valistmem->getType())));
   // Pass a i8* pointer to the actual struct to LLVM's va_start intrinsic.
   return DtoBitCast(valistmem, getVoidPtrType());
 }

 void vaCopy(DLValue *dest, DValue *src) override {
   // Analog to va_start, we first need to allocate a new __va_list struct on
   // the stack and set `dest` to its address.
   LLValue *valistmem = DtoRawAlloca(getValistType(), 0, "__va_list_mem");
   DtoStore(valistmem,
            DtoBitCast(DtoLVal(dest), getPtrToType(valistmem->getType())));
   // Then fill the new struct with a bitcopy of the source struct.
   // `src` is a char* pointer to the source struct.
   DtoMemCpy(valistmem, DtoRVal(src));
 }

DValue* DtoAAIn(Loc& loc, Type* type, DValue* aa, DValue* key)
{
    // D1:
    // call:
    // extern(C) void* _aaIn(AA aa*, TypeInfo keyti, void* pkey)

    // D2:
    // call:
    // extern(C) void* _aaInX(AA aa*, TypeInfo keyti, void* pkey)

    // first get the runtime function
#if DMDV2
    llvm::Function* func = LLVM_D_GetRuntimeFunction(gIR->module, "_aaInX");
#else
    llvm::Function* func = LLVM_D_GetRuntimeFunction(gIR->module, "_aaIn");
#endif
    LLFunctionType* funcTy = func->getFunctionType();

    if (Logger::enabled())
        Logger::cout() << "_aaIn = " << *func << '\n';

    // aa param
    LLValue* aaval = aa->getRVal();
    if (Logger::enabled())
    {
        Logger::cout() << "aaval: " << *aaval << '\n';
        Logger::cout() << "totype: " << *funcTy->getParamType(0) << '\n';
    }
    aaval = DtoBitCast(aaval, funcTy->getParamType(0));

    // keyti param
#if DMDV2
    LLValue* keyti = to_keyti(aa);
#else
    LLValue* keyti = to_keyti(key);
#endif
    keyti = DtoBitCast(keyti, funcTy->getParamType(1));

    // pkey param
    LLValue* pkey = makeLValue(loc, key);
    pkey = DtoBitCast(pkey, getVoidPtrType());

    // call runtime
    LLValue* ret = gIR->CreateCallOrInvoke3(func, aaval, keyti, pkey, "aa.in").getInstruction();

    // cast return value
    LLType* targettype = DtoType(type);
    if (ret->getType() != targettype)
        ret = DtoBitCast(ret, targettype);

    return new DImValue(type, ret);
}

LLValue *DLValue::getRVal() {
  if (DtoIsInMemoryOnly(type->toBasetype())) {
    llvm_unreachable("getRVal() for memory-only type");
    return nullptr;
  }

  LLValue *rawValue = DtoLoad(val);
  if (type->toBasetype()->ty != Tbool)
    return rawValue;

  assert(rawValue->getType() == llvm::Type::getInt8Ty(gIR->context()));
  return gIR->ir->CreateTrunc(rawValue, llvm::Type::getInt1Ty(gIR->context()));
}

 // Get struct from ABI-mangled representation
 LLValue* get(Type* dty, DValue* v)
 {
     LLValue* lval;
     if (v->isLVal()) {
         lval = v->getLVal();
     } else {
         // No memory location, create one.
         LLValue* rval = v->getRVal();
         lval = DtoRawAlloca(rval->getType(), 0);
         DtoStore(rval, lval);
     }
     
     LLType* pTy = getPtrToType(DtoType(dty));
     return DtoLoad(DtoBitCast(lval, pTy), "get-result");
 }

void DtoResolveNestedContext(Loc loc, ClassDeclaration *decl, LLValue *value)
#endif
{
    Logger::println("Resolving nested context");
    LOG_SCOPE;

    // get context
    LLValue* nest = DtoNestedContext(loc, decl);

    // store into right location
    if (!llvm::dyn_cast<llvm::UndefValue>(nest)) {
        size_t idx = decl->vthis->ir.irField->index;
        LLValue* gep = DtoGEPi(value,0,idx,".vthis");
        DtoStore(DtoBitCast(nest, gep->getType()->getContainedType(0)), gep);
    }
}

LLValue* DtoStructEquals(TOK op, DValue* lhs, DValue* rhs)
{
    Type* t = lhs->getType()->toBasetype();
    assert(t->ty == Tstruct);

    // set predicate
    llvm::ICmpInst::Predicate cmpop;
    if (op == TOKequal || op == TOKidentity)
        cmpop = llvm::ICmpInst::ICMP_EQ;
    else
        cmpop = llvm::ICmpInst::ICMP_NE;

    // call memcmp
    size_t sz = getTypePaddedSize(DtoType(t));
    LLValue* val = DtoMemCmp(lhs->getRVal(), rhs->getRVal(), DtoConstSize_t(sz));
    return gIR->ir->CreateICmp(cmpop, val, LLConstantInt::get(val->getType(), 0, false), "tmp");
}

 // Turn a struct into an ABI-mangled representation
 LLValue* put(Type* dty, DValue* v)
 {
     LLValue* lval;
     if (v->isLVal()) {
         lval = v->getLVal();
     } else {
         // No memory location, create one.
         LLValue* rval = v->getRVal();
         lval = DtoRawAlloca(rval->getType(), 0);
         DtoStore(rval, lval);
     }
     
     LLType* abiTy = getAbiType(dty);
     assert(abiTy && "Why are we rewriting a non-rewritten type?");
     
     LLType* pTy = getPtrToType(abiTy);
     return DtoLoad(DtoBitCast(lval, pTy), "put-result");
 }

DValue *binMin(Loc &loc, Type *type, DValue *lhs, Expression *rhs,
               bool loadLhsAfterRhs) {
  Type *lhsType = lhs->type->toBasetype();
  Type *rhsType = rhs->type->toBasetype();

  if (lhsType != rhsType && lhsType->ty == Tpointer && rhsType->isintegral()) {
    Logger::println("Subtracting integer from pointer");
    return emitPointerOffset(loc, lhs, rhs, true, type, loadLhsAfterRhs);
  }

  auto rvals = evalSides(lhs, rhs, loadLhsAfterRhs);

  if (lhsType->ty == Tpointer && rhsType->ty == Tpointer) {
    LLValue *l = DtoRVal(rvals.lhs);
    LLValue *r = DtoRVal(rvals.rhs);
    LLType *llSizeT = DtoSize_t();
    l = gIR->ir->CreatePtrToInt(l, llSizeT);
    r = gIR->ir->CreatePtrToInt(r, llSizeT);
    LLValue *diff = gIR->ir->CreateSub(l, r);
    LLType *llType = DtoType(type);
    if (diff->getType() != llType)
      diff = gIR->ir->CreateIntToPtr(diff, llType);
    return new DImValue(type, diff);
  }

  if (type->ty == Tnull)
    return DtoNullValue(type, loc);
  if (type->iscomplex())
    return DtoComplexMin(loc, type, rvals.lhs, rvals.rhs);

  LLValue *l = DtoRVal(DtoCast(loc, rvals.lhs, type));
  LLValue *r = DtoRVal(DtoCast(loc, rvals.rhs, type));

  if (auto aa = isAssociativeArrayAndNull(type, l, r))
    return aa;

  LLValue *res = (type->isfloating() ? gIR->ir->CreateFSub(l, r)
                                     : gIR->ir->CreateSub(l, r));

  return new DImValue(type, res);
}

LLValue* DtoStructEquals(TOK op, DValue* lhs, DValue* rhs)
{
    Type* t = lhs->getType()->toBasetype();
    assert(t->ty == Tstruct);

    // set predicate
    llvm::ICmpInst::Predicate cmpop;
    if (op == TOKequal || op == TOKidentity)
        cmpop = llvm::ICmpInst::ICMP_EQ;
    else
        cmpop = llvm::ICmpInst::ICMP_NE;

    // empty struct? EQ always true, NE always false
    if (static_cast<TypeStruct*>(t)->sym->fields.dim == 0)
        return DtoConstBool(cmpop == llvm::ICmpInst::ICMP_EQ);

    // call memcmp
    size_t sz = getTypePaddedSize(DtoType(t));
    LLValue* val = DtoMemCmp(lhs->getRVal(), rhs->getRVal(), DtoConstSize_t(sz));
    return gIR->ir->CreateICmp(cmpop, val, LLConstantInt::get(val->getType(), 0, false));
}