C++ VarDeclaration::semantic方法代码示例

 /* Returns:
  *  0       this member doesn't need further processing to determine struct size
  *  1       this member does
  */
 static int func(Dsymbol *s, void *param)
 {   SV *psv = (SV *)param;
     VarDeclaration *v = s->isVarDeclaration();
     if (v)
     {
         if (v->scope)
             v->semantic(NULL);
         if (v->storage_class & (STCstatic | STCextern | STCtls | STCgshared | STCmanifest | STCctfe | STCtemplateparameter))
             return 0;
         if (v->isField() && v->sem >= SemanticDone)
             return 0;
         return 1;
     }
     return 0;
 }

Expression *fromConstInitializer(Expression *e1)
{
    //printf("fromConstInitializer(%s)\n", e1->toChars());
    if (e1->op == TOKvar)
    {   VarExp *ve = (VarExp *)e1;
        VarDeclaration *v = ve->var->isVarDeclaration();
        if (v && !v->originalType && v->scope)  // semantic() not yet run
            v->semantic (v->scope);
        if (v && v->isConst() && v->init)
        {   Expression *ei = v->init->toExpression();
            if (ei && ei->type)
                e1 = ei;
        }
    }
    return e1;
}

            /* Returns:
             *  0       this member doesn't need further processing to determine struct size
             *  1       this member does
             */
            static int func(Dsymbol *s, void *param)
            {
                VarDeclaration *v = s->isVarDeclaration();
                if (v)
                {
                    /* Bugzilla 12799: enum a = ...; is a VarDeclaration and
                     * STCmanifest is already set in parssing stage. So we can
                     * check this before the semantic() call.
                     */
                    if (v->storage_class & STCmanifest)
                        return 0;

                    if (v->scope)
                        v->semantic(NULL);
                    if (v->storage_class & (STCstatic | STCextern | STCtls | STCgshared | STCmanifest | STCctfe | STCtemplateparameter))
                        return 0;
                    if (v->isField() && v->sem >= SemanticDone)
                        return 0;
                    return 1;
                }
                return 0;
            }

Expression *createTypeInfoArray(Scope *sc, Expression *exps[], size_t dim)
{
#if 1
    /*
     * Pass a reference to the TypeInfo_Tuple corresponding to the types of the
     * arguments. Source compatibility is maintained by computing _arguments[]
     * at the start of the called function by offseting into the TypeInfo_Tuple
     * reference.
     */
    Parameters *args = new Parameters;
    args->setDim(dim);
    for (size_t i = 0; i < dim; i++)
    {   Parameter *arg = new Parameter(STCin, exps[i]->type, NULL, NULL);
        (*args)[i] = arg;
    }
    TypeTuple *tup = new TypeTuple(args);
    Expression *e = tup->getTypeInfo(sc);
    e = e->optimize(WANTvalue);
    assert(e->op == TOKsymoff);         // should be SymOffExp

    return e;
#else
    /* Improvements:
     * 1) create an array literal instead,
     * as it would eliminate the extra dereference of loading the
     * static variable.
     */

    ArrayInitializer *ai = new ArrayInitializer(0);
    VarDeclaration *v;
    Type *t;
    Expression *e;
    OutBuffer buf;
    Identifier *id;
    char *name;

    // Generate identifier for _arguments[]
    buf.writestring("_arguments_");
    for (int i = 0; i < dim; i++)
    {   t = exps[i]->type;
        t->toDecoBuffer(&buf);
    }
    buf.writeByte(0);
    id = Lexer::idPool((char *)buf.data);

    Module *m = sc->module;
    Dsymbol *s = m->symtab->lookup(id);

    if (s && s->parent == m)
    {   // Use existing one
        v = s->isVarDeclaration();
        assert(v);
    }
    else
    {   // Generate new one

        for (int i = 0; i < dim; i++)
        {   t = exps[i]->type;
            e = t->getTypeInfo(sc);
            ai->addInit(new IntegerExp(i), new ExpInitializer(Loc(), e));
        }

        t = Type::typeinfo->type->arrayOf();
        ai->type = t;
        v = new VarDeclaration(0, t, id, ai);
        m->members->push(v);
        m->symtabInsert(v);
        sc = sc->push();
        sc->linkage = LINKc;
        sc->stc = STCstatic | STCcomdat;
        ai->semantic(sc, t);
        v->semantic(sc);
        v->parent = m;
        sc = sc->pop();
    }
    e = new VarExp(Loc(), v);
    e = e->semantic(sc);
    return e;
#endif
}

Expression *createTypeInfoArray(Scope *sc, Expression *exps[], int dim)
{
#if 1
    /* Get the corresponding TypeInfo_Tuple and
     * point at its elements[].
     */

    /* Create the TypeTuple corresponding to the types of args[]
     */
    Parameters *args = new Parameters;
    args->setDim(dim);
    for (size_t i = 0; i < dim; i++)
    {   Parameter *arg = new Parameter(STCin, exps[i]->type, NULL, NULL);
        args->tdata()[i] = arg;
    }
    TypeTuple *tup = new TypeTuple(args);
    Expression *e = tup->getTypeInfo(sc);
    e = e->optimize(WANTvalue);
    assert(e->op == TOKsymoff);         // should be SymOffExp

#if BREAKABI
    /*
     * Should just pass a reference to TypeInfo_Tuple instead,
     * but that would require existing code to be recompiled.
     * Source compatibility can be maintained by computing _arguments[]
     * at the start of the called function by offseting into the
     * TypeInfo_Tuple reference.
     */

#else
    // Advance to elements[] member of TypeInfo_Tuple
    SymOffExp *se = (SymOffExp *)e;
    se->offset += PTRSIZE + PTRSIZE;

    // Set type to TypeInfo[]*
    se->type = Type::typeinfo->type->arrayOf()->pointerTo();

    // Indirect to get the _arguments[] value
    e = new PtrExp(0, se);
    e->type = se->type->next;
#endif
    return e;
#else
    /* Improvements:
     * 1) create an array literal instead,
     * as it would eliminate the extra dereference of loading the
     * static variable.
     */

    ArrayInitializer *ai = new ArrayInitializer(0);
    VarDeclaration *v;
    Type *t;
    Expression *e;
    OutBuffer buf;
    Identifier *id;
    char *name;

    // Generate identifier for _arguments[]
    buf.writestring("_arguments_");
    for (int i = 0; i < dim; i++)
    {   t = exps[i]->type;
        t->toDecoBuffer(&buf);
    }
    buf.writeByte(0);
    id = Lexer::idPool((char *)buf.data);

    Module *m = sc->module;
    Dsymbol *s = m->symtab->lookup(id);

    if (s && s->parent == m)
    {   // Use existing one
        v = s->isVarDeclaration();
        assert(v);
    }
    else
    {   // Generate new one

        for (int i = 0; i < dim; i++)
        {   t = exps[i]->type;
            e = t->getTypeInfo(sc);
            ai->addInit(new IntegerExp(i), new ExpInitializer(0, e));
        }

        t = Type::typeinfo->type->arrayOf();
        ai->type = t;
        v = new VarDeclaration(0, t, id, ai);
        m->members->push(v);
        m->symtabInsert(v);
        sc = sc->push();
        sc->linkage = LINKc;
        sc->stc = STCstatic | STCcomdat;
        ai->semantic(sc, t);
        v->semantic(sc);
        v->parent = m;
        sc = sc->pop();
    }
    e = new VarExp(0, v);
    e = e->semantic(sc);
    return e;
#endif
//.........这里部分代码省略.........

void VarDeclaration::semantic(Scope *sc)
{
#if 0
    printf("VarDeclaration::semantic('%s', parent = '%s')\n", toChars(), sc->parent->toChars());
    printf(" type = %s\n", type ? type->toChars() : "null");
    printf(" stc = x%x\n", sc->stc);
    printf(" storage_class = x%x\n", storage_class);
    printf("linkage = %d\n", sc->linkage);
    //if (strcmp(toChars(), "mul") == 0) halt();
#endif

    storage_class |= sc->stc;
    if (storage_class & STCextern && init)
        error("extern symbols cannot have initializers");

    AggregateDeclaration *ad = isThis();
    if (ad)
        storage_class |= ad->storage_class & STC_TYPECTOR;

    /* If auto type inference, do the inference
     */
    int inferred = 0;
    if (!type)
    {   inuse++;
        type = init->inferType(sc);
        inuse--;
        inferred = 1;

        /* This is a kludge to support the existing syntax for RAII
         * declarations.
         */
        storage_class &= ~STCauto;
        originalType = type;
    }
    else
    {   if (!originalType)
            originalType = type;
        type = type->semantic(loc, sc);
    }
    //printf(" semantic type = %s\n", type ? type->toChars() : "null");

    type->checkDeprecated(loc, sc);
    linkage = sc->linkage;
    this->parent = sc->parent;
    //printf("this = %p, parent = %p, '%s'\n", this, parent, parent->toChars());
    protection = sc->protection;
    //printf("sc->stc = %x\n", sc->stc);
    //printf("storage_class = x%x\n", storage_class);

#if DMDV2
    if (storage_class & STCgshared && global.params.safe && !sc->module->safe)
    {
        error("__gshared not allowed in safe mode; use shared");
    }
#endif

    Dsymbol *parent = toParent();
    FuncDeclaration *fd = parent->isFuncDeclaration();

    Type *tb = type->toBasetype();
    if (tb->ty == Tvoid && !(storage_class & STClazy))
    {   error("voids have no value");
        type = Type::terror;
        tb = type;
    }
    if (tb->ty == Tfunction)
    {   error("cannot be declared to be a function");
        type = Type::terror;
        tb = type;
    }
    if (tb->ty == Tstruct)
    {   TypeStruct *ts = (TypeStruct *)tb;

        if (!ts->sym->members)
        {
            error("no definition of struct %s", ts->toChars());
        }
    }
    if ((storage_class & STCauto) && !inferred)
       error("storage class 'auto' has no effect if type is not inferred, did you mean 'scope'?");

    if (tb->ty == Ttuple)
    {   /* Instead, declare variables for each of the tuple elements
         * and add those.
         */
        TypeTuple *tt = (TypeTuple *)tb;
        size_t nelems = Parameter::dim(tt->arguments);
        Objects *exps = new Objects();
        exps->setDim(nelems);
        Expression *ie = init ? init->toExpression() : NULL;

        for (size_t i = 0; i < nelems; i++)
        {   Parameter *arg = Parameter::getNth(tt->arguments, i);

            OutBuffer buf;
            buf.printf("_%s_field_%zu", ident->toChars(), i);
            buf.writeByte(0);
            const char *name = (const char *)buf.extractData();
            Identifier *id = Lexer::idPool(name);

//.........这里部分代码省略.........

Dsymbol *ArrayScopeSymbol::search(Loc loc, Identifier *ident, int flags)
{
    //printf("ArrayScopeSymbol::search('%s', flags = %d)\n", ident->toChars(), flags);
    if (ident == Id::dollar)
    {   VarDeclaration **pvar;
        Expression *ce;

    L1:

        if (td)
        {   /* $ gives the number of elements in the tuple
             */
            VarDeclaration *v = new VarDeclaration(loc, Type::tsize_t, Id::dollar, NULL);
            Expression *e = new IntegerExp(Loc(), td->objects->dim, Type::tsize_t);
            v->init = new ExpInitializer(Loc(), e);
            v->storage_class |= STCstatic | STCconst;
            v->semantic(sc);
            return v;
        }

        if (type)
        {   /* $ gives the number of type entries in the type tuple
             */
            VarDeclaration *v = new VarDeclaration(loc, Type::tsize_t, Id::dollar, NULL);
            Expression *e = new IntegerExp(Loc(), type->arguments->dim, Type::tsize_t);
            v->init = new ExpInitializer(Loc(), e);
            v->storage_class |= STCstatic | STCconst;
            v->semantic(sc);
            return v;
        }

        if (exp->op == TOKindex)
        {   /* array[index] where index is some function of $
             */
            IndexExp *ie = (IndexExp *)exp;

            pvar = &ie->lengthVar;
            ce = ie->e1;
        }
        else if (exp->op == TOKslice)
        {   /* array[lwr .. upr] where lwr or upr is some function of $
             */
            SliceExp *se = (SliceExp *)exp;

            pvar = &se->lengthVar;
            ce = se->e1;
        }
        else if (exp->op == TOKarray)
        {   /* array[e0, e1, e2, e3] where e0, e1, e2 are some function of $
             * $ is a opDollar!(dim)() where dim is the dimension(0,1,2,...)
             */
            ArrayExp *ae = (ArrayExp *)exp;

            pvar = &ae->lengthVar;
            ce = ae->e1;
        }
        else
            /* Didn't find $, look in enclosing scope(s).
             */
            return NULL;

        while (ce->op == TOKcomma)
            ce = ((CommaExp *)ce)->e2;

        /* If we are indexing into an array that is really a type
         * tuple, rewrite this as an index into a type tuple and
         * try again.
         */
        if (ce->op == TOKtype)
        {
            Type *t = ((TypeExp *)ce)->type;
            if (t->ty == Ttuple)
            {   type = (TypeTuple *)t;
                goto L1;
            }
        }

        /* *pvar is lazily initialized, so if we refer to $
         * multiple times, it gets set only once.
         */
        if (!*pvar)             // if not already initialized
        {   /* Create variable v and set it to the value of $
             */
            VarDeclaration *v;
            Type *t;
            if (ce->op == TOKtuple)
            {   /* It is for an expression tuple, so the
                 * length will be a const.
                 */
                Expression *e = new IntegerExp(Loc(), ((TupleExp *)ce)->exps->dim, Type::tsize_t);
                v = new VarDeclaration(loc, Type::tsize_t, Id::dollar, new ExpInitializer(Loc(), e));
                v->storage_class |= STCstatic | STCconst;
            }
            else if (ce->type && (t = ce->type->toBasetype()) != NULL &&
                     (t->ty == Tstruct || t->ty == Tclass))
            {   // Look for opDollar
                assert(exp->op == TOKarray || exp->op == TOKslice);
                AggregateDeclaration *ad = NULL;

                if (t->ty == Tclass)
//.........这里部分代码省略.........

Dsymbol *ArrayScopeSymbol::search(Loc loc, Identifier *ident, int flags)
{
    //printf("ArrayScopeSymbol::search('%s', flags = %d)\n", ident->toChars(), flags);
    if (ident == Id::length || ident == Id::dollar)
    {   VarDeclaration **pvar;
        Expression *ce;

L1:

        if (td)
        {
            VarDeclaration *v = new VarDeclaration(loc, Type::tsize_t, Id::dollar, NULL);
            Expression *e = new IntegerExp(0, td->objects->dim, Type::tsize_t);
            v->init = new ExpInitializer(0, e);
            v->storage_class |= STCstatic | STCconst;
            v->semantic(sc);
            return v;
        }

        if (type)
        {
            VarDeclaration *v = new VarDeclaration(loc, Type::tsize_t, Id::dollar, NULL);
            Expression *e = new IntegerExp(0, type->arguments->dim, Type::tsize_t);
            v->init = new ExpInitializer(0, e);
            v->storage_class |= STCstatic | STCconst;
            v->semantic(sc);
            return v;
        }

        if (exp->op == TOKindex)
        {
            IndexExp *ie = (IndexExp *)exp;

            pvar = &ie->lengthVar;
            ce = ie->e1;
        }
        else if (exp->op == TOKslice)
        {
            SliceExp *se = (SliceExp *)exp;

            pvar = &se->lengthVar;
            ce = se->e1;
        }
        else
            return NULL;

        if (ce->op == TOKtype)
        {
            Type *t = ((TypeExp *)ce)->type;
            if (t->ty == Ttuple)
            {   type = (TypeTuple *)t;
                goto L1;
            }
        }

        if (!*pvar)
        {
            VarDeclaration *v = new VarDeclaration(loc, Type::tsize_t, Id::dollar, NULL);

            if (ce->op == TOKvar)
            {   // if ce is const, get its initializer
                ce = fromConstInitializer(WANTvalue | WANTinterpret, ce);
            }

            if (ce->op == TOKstring)
            {   /* It is for a string literal, so the
                * length will be a const.
                 */
                Expression *e = new IntegerExp(0, ((StringExp *)ce)->len, Type::tsize_t);
                v->init = new ExpInitializer(0, e);
                v->storage_class |= STCstatic | STCconst;
            }
            else if (ce->op == TOKarrayliteral)
            {   /* It is for an array literal, so the
                * length will be a const.
                 */
                Expression *e = new IntegerExp(0, ((ArrayLiteralExp *)ce)->elements->dim, Type::tsize_t);
                v->init = new ExpInitializer(0, e);
                v->storage_class |= STCstatic | STCconst;
            }
            else if (ce->op == TOKtuple)
            {   /* It is for an expression tuple, so the
                * length will be a const.
                 */
                Expression *e = new IntegerExp(0, ((TupleExp *)ce)->exps->dim, Type::tsize_t);
                v->init = new ExpInitializer(0, e);
                v->storage_class |= STCstatic | STCconst;
            }
            *pvar = v;
        }
        (*pvar)->semantic(sc);
        return (*pvar);
    }
    return NULL;
}

Dsymbol *ArrayScopeSymbol::search(Loc loc, Identifier *ident, int flags)
{
    //printf("ArrayScopeSymbol::search('%s', flags = %d)\n", ident->toChars(), flags);
    if (ident == Id::length || ident == Id::dollar)
    {   VarDeclaration **pvar;
        Expression *ce;

        if (ident == Id::length && !global.params.useDeprecated)
            error("using 'length' inside [ ] is deprecated, use '$' instead");

    L1:

        if (td)
        {   /* $ gives the number of elements in the tuple
             */
            VarDeclaration *v = new VarDeclaration(loc, Type::tsize_t, Id::dollar, NULL);
            Expression *e = new IntegerExp(0, td->objects->dim, Type::tsize_t);
            v->init = new ExpInitializer(0, e);
            v->storage_class |= STCstatic | STCconst;
            v->semantic(sc);
            return v;
        }

        if (type)
        {   /* $ gives the number of type entries in the type tuple
             */
            VarDeclaration *v = new VarDeclaration(loc, Type::tsize_t, Id::dollar, NULL);
            Expression *e = new IntegerExp(0, type->arguments->dim, Type::tsize_t);
            v->init = new ExpInitializer(0, e);
            v->storage_class |= STCstatic | STCconst;
            v->semantic(sc);
            return v;
        }

        if (exp->op == TOKindex)
        {   /* array[index] where index is some function of $
             */
            IndexExp *ie = (IndexExp *)exp;

            pvar = &ie->lengthVar;
            ce = ie->e1;
        }
        else if (exp->op == TOKslice)
        {   /* array[lwr .. upr] where lwr or upr is some function of $
             */
            SliceExp *se = (SliceExp *)exp;

            pvar = &se->lengthVar;
            ce = se->e1;
        }
        else if (exp->op == TOKarray)
        {   /* array[e0, e1, e2, e3] where e0, e1, e2 are some function of $
             * $ is a opDollar!(dim)() where dim is the dimension(0,1,2,...)
             */
            ArrayExp *ae = (ArrayExp *)exp;
            AggregateDeclaration *ad = NULL;

            Type *t = ae->e1->type->toBasetype();
            if (t->ty == Tclass)
            {
                ad = ((TypeClass *)t)->sym;
            }
            else if (t->ty == Tstruct)
            {
                ad = ((TypeStruct *)t)->sym;
            }
            assert(ad);

            Dsymbol *dsym = search_function(ad, Id::opDollar);
            if (!dsym)  // no dollar exists -- search in higher scope
                return NULL;
            VarDeclaration *v = ae->lengthVar;
            if (!v)
            {   // $ is lazily initialized. Create it now.
                TemplateDeclaration *td = dsym->isTemplateDeclaration();
                if (td)
                {   // Instantiate opDollar!(dim) with the index as a template argument
                    Objects *tdargs = new Objects();
                    tdargs->setDim(1);

                    Expression *x = new IntegerExp(0, ae->currentDimension, Type::tsize_t);
                    x = x->semantic(sc);
                    tdargs->data[0] = x;

                    //TemplateInstance *ti = new TemplateInstance(loc, td, tdargs);
                    //ti->semantic(sc);

                    DotTemplateInstanceExp *dte = new DotTemplateInstanceExp(loc, ae->e1, td->ident, tdargs);

                    v = new VarDeclaration(loc, NULL, Id::dollar, new ExpInitializer(0, dte));
                }
                else
                {   /* opDollar exists, but it's a function, not a template.
                     * This is acceptable ONLY for single-dimension indexing.
                     * Note that it's impossible to have both template & function opDollar,
                     * because both take no arguments.
                     */
                    if (ae->arguments->dim != 1) {
                        ae->error("%s only defines opDollar for one dimension", ad->toChars());
                        return NULL;
//.........这里部分代码省略.........