C++ VariableScope类代码示例

  void VariableScope::Info::visit(Object* obj, ObjectVisitor& visit) {
    auto_visit(obj, visit);

    VariableScope* vs = as<VariableScope>(obj);

    if(!vs->isolated()) {
      Object** ary = vs->stack_locals();

      if(Fiber* fib = try_as<Fiber>(vs->fiber())) {
        FiberData* data = fib->data();

        AddressDisplacement dis(data->data_offset(),
                                data->data_lower_bound(),
                                data->data_upper_bound());

        ary = dis.displace(ary);
      }

      size_t locals = vs->number_of_locals();

      for(size_t i = 0; i < locals; i++) {
        visit.call(ary[i]);
      }
    }
  }

  void VariableScope::Info::mark(Object* obj, ObjectMark& mark) {
    auto_mark(obj, mark);

    VariableScope* vs = as<VariableScope>(obj);

    if(!vs->isolated()) {
      Object** ary = vs->locals_;

      if(Fiber* fib = try_as<Fiber>(vs->fiber())) {
        FiberData* data = fib->data();

        if(data) {
          AddressDisplacement dis(data->data_offset(),
                                  data->data_lower_bound(),
                                  data->data_upper_bound());

          ary = dis.displace(ary);
        }
      }

      size_t locals = vs->number_of_locals();

      for(size_t i = 0; i < locals; i++) {
        if(Object* tmp = mark.call(ary[i])) {
          ary[i] = tmp;
        }
      }
    }
  }

  void GarbageCollector::visit_variable_scope(CallFrame* call_frame,
      StackVariables* scope, ObjectVisitor& visit)
  {

    scope->self_ = visit.call(scope->self());
    scope->block_ = visit.call(scope->block());
    scope->module_ = (Module*)visit.call(scope->module());

    int locals = call_frame->cm->backend_method()->number_of_locals;

    for(int i = 0; i < locals; i++) {
      Object* local = scope->get_local(i);
      if(local->reference_p()) {
        scope->set_local(i, visit.call(local));
      }
    }

    VariableScope* parent = scope->parent();
    if(parent && parent->reference_p()) {
      scope->parent_ = ((VariableScope*)visit.call(parent));
    }

    VariableScope* on_heap = scope->on_heap();
    if(on_heap) {
      scope->on_heap_ = ((VariableScope*)visit.call(on_heap));
    }
  }

 Object* VariableScope::set_locked(STATE) {
   _flags_ |= CallFrame::cScopeLocked;
   VariableScope* parent = this->parent();
   while(parent && !parent->nil_p()) {
     parent->set_locked(state);
     parent = parent->parent();
   }
   return cNil;
 }

  VariableScope* StackVariables::create_heap_alias(STATE,
      CallFrame* call_frame, bool full)
  {
    if(on_heap_) return on_heap_;

    VMMethod* vmm = call_frame->cm->backend_method();
    VariableScope* scope = state->new_struct<VariableScope>(
        G(variable_scope), vmm->number_of_locals * sizeof(Object*));

    if(parent_) {
      scope->parent(state, parent_);
    } else {
      scope->parent(state, (VariableScope*)Qnil);
    }

    scope->self(state, self_);
    scope->block(state, block_);
    scope->module(state, module_);
    scope->method(state, call_frame->cm);

    scope->number_of_locals_ = vmm->number_of_locals;

    if(full) {
      scope->isolated_ = false;
      scope->point_locals_to(locals_);
    } else {
      scope->isolated_ = true;
      scope->point_locals_to(scope->heap_locals_);
    }

    on_heap_ = scope;

    return scope;
  }

  VariableScope* VariableScope::synthesize(STATE, CompiledMethod* method,
                                           Module* module, Object* parent,
                                           Object* self, Object* block,
                                           Tuple* locals)
  {
    VariableScope* scope = state->new_object<VariableScope>(G(variable_scope));

    scope->block(state, block);
    scope->module(state, module);
    scope->method(state, method);

    if(VariableScope* vs = try_as<VariableScope>(parent)) {
      scope->parent(state, vs);
    } else {
      scope->parent(state, nil<VariableScope>());
    }

    scope->heap_locals(state, locals);
    scope->last_match(state, cNil);

    scope->self(state, self);
    scope->number_of_locals_ = locals->num_fields();
    scope->isolated_ = true;
    scope->locals_ = 0;
    scope->block_as_method_ = 0;

    return scope;
  }

  /**
   * Walks the chain of objects accessible from the specified CallFrame.
   */
  void GarbageCollector::verify_call_frame(CallFrame* top_call_frame,
                                           AddressDisplacement* offset)
  {
    CallFrame* call_frame = top_call_frame;

    while(call_frame) {
      call_frame = displace(call_frame, offset);

      if(call_frame->constant_scope_) {
        call_frame->constant_scope_->validate();
      }

      if(call_frame->compiled_code) {
        call_frame->compiled_code->validate();
      }

      if(call_frame->compiled_code) {
        native_int stack_size = call_frame->compiled_code->stack_size()->to_native();
        for(native_int i = 0; i < stack_size; i++) {
          Object* obj = call_frame->stk[i];
          obj->validate();
        }
      }

      VariableScope* scope = call_frame->top_scope_;
      if(call_frame->multiple_scopes_p() && scope && !scope->nil_p()) {
        scope->validate();
      }

      if(BlockEnvironment* env = call_frame->block_env()) {
        env->validate();
      }

      Arguments* args = displace(call_frame->arguments, offset);

      if(!call_frame->inline_method_p() && args) {
        args->recv()->validate();
        args->block()->validate();

        Object** ary = displace(args->arguments(), offset);
        for(uint32_t i = 0; i < args->total(); i++) {
          ary[i]->validate();
        }
      }

      if(call_frame->scope && call_frame->compiled_code) {
        verify_variable_scope(call_frame, displace(call_frame->scope, offset));
      }

      call_frame = call_frame->previous;
    }
  }

  void VariableScope::Info::visit(Object* obj, ObjectVisitor& visit) {
    auto_visit(obj, visit);

    VariableScope* vs = as<VariableScope>(obj);

    if(!vs->isolated()) {
      Object** ary = vs->stack_locals();
      size_t locals = vs->number_of_locals();

      for(size_t i = 0; i < locals; i++) {
        visit.call(ary[i]);
      }
    }
  }

  VariableScope* CallFrame::method_scope(STATE) {
    VariableScope* current = promote_scope(state);
    if(!multiple_scopes_p()) return current;

    for(;;) {
      if(current->block_as_method_p()) return current;
      VariableScope* parent = current->parent();
      if(!parent->nil_p()) {
        current = parent;
      } else {
        return current;
      }
    }

    assert("should not be here" && 0);
  }

  void VariableScope::Info::mark(Object* obj, ObjectMark& mark) {
    auto_mark(obj, mark);

    VariableScope* vs = as<VariableScope>(obj);

    vs->fixup();


    Object* tmp;

    size_t locals = vs->number_of_locals();
    for(size_t i = 0; i < locals; i++) {
      tmp = mark.call(vs->get_local(i));
      if(tmp) vs->set_local(mark.state(), i, tmp);
    }
  }

std::string DocumentImpl::vardump( VariableScope& vscope)
{
	std::ostringstream rt;

	VariableScope::const_iterator vi = vscope.begin(), ve = vscope.end();
	while (vi != ve)
	{
		if (vi != vscope.begin())
		{
			rt << ", ";
		}
		rt << variableName( vi->first) << " = '" << vscope.getValue( vi->second) << "'";
		++vi;
	}
	return rt.str();
}

  VariableScope* CallFrame::method_scope(STATE) {
    VariableScope* current = promote_scope(state);
    if(!multiple_scopes_p()) return current;

    for(;;) {
      if(current->block_as_method_p()) return current;
      VariableScope* parent = current->parent();
      if(!parent->nil_p()) {
        current = parent;
      } else {
        return current;
      }
    }

    // Shouldn't ever get here.
    return 0;
  }

  void VariableScope::Info::mark(Object* obj, memory::ObjectMark& mark) {
    auto_mark(obj, mark);

    VariableScope* vs = as<VariableScope>(obj);

    if(!vs->isolated_p()) {
      Object** ary = vs->locals();

      size_t locals = vs->number_of_locals();

      for(size_t i = 0; i < locals; i++) {
        if(Object* tmp = mark.call(ary[i])) {
          ary[i] = tmp;
        }
      }
    }
  }

  Object* rbx_zsuper_send(STATE, CallFrame* call_frame, Symbol* name, Object* block) {
    Object* const recv = call_frame->self();

    VariableScope* scope = call_frame->method_scope(state);
    assert(scope);

    VMMethod* v = scope->method()->backend_method();
    Object* splat_obj = 0;
    Array* splat = 0;

    size_t arg_count = v->total_args;

    if(v->splat_position >= 0) {
      splat_obj = scope->get_local(state, v->splat_position);
      splat = try_as<Array>(splat_obj);
      if(splat) {
        arg_count += splat->size();
      } else {
        arg_count++;
      }
    }

    Tuple* tup = Tuple::create(state, arg_count);
    for(int i = 0; i < v->total_args; i++) {
      tup->put(state, i, scope->get_local(state, i));
    }

    if(splat) {
      for(size_t i = 0; i < splat->size(); i++) {
        tup->put(state, i + v->total_args, splat->get(state, i));
      }
    } else if(splat_obj) {
      tup->put(state, v->total_args, splat_obj);
    }

    Arguments out_args(name, recv, block, arg_count, 0);
    out_args.use_tuple(tup, arg_count);

    LookupData lookup(recv, call_frame->module()->superclass(), G(sym_private));
    Dispatch dis(name);

    return dis.send(state, call_frame, lookup, out_args, eSuper);
  }

  Object* StackVariables::last_match(STATE) {
    // For closures, get back to the top of the chain and get that
    // last_match.
    if(parent_) {
      VariableScope* scope = parent_;
      while(RTEST(scope->parent())) {
        scope = scope->parent();
      }

      return scope->last_match();
    }

    // Otherwise, if this has a heap alias, get the last_match from there.
    if(on_heap_) {
      return on_heap_->last_match();

    // Lastly, use the local one. This is where a last_match begins life.
    } else {
      return last_match_;
    }
  }