feat: BroadcastChannel 构造器方法与绑定与注册表剪枝

crates/oxide_vm/src/bindings/bind_broadcast_channel.rs

@@ -0,0 +1,137 @@
+use std::sync::Arc;
+
+use crate::bind_constructor;
+use crate::bindings::{apply_binding_table, bind_accessor_getter, configure_native_constructor};
+use oxide_kernel::kernel::{KernelCore, KernelSession};
+use oxide_types::object::{JsObject, PropAttributes};
+use oxide_types::value::JsValue;
+
+/// 把 BroadcastChannel 构造器与原型方法绑定到 global。
+///
+/// 935.2.1 的两枚 P 字段（`broadcast_channel_constructor` /
+/// `broadcast_channel_proto`）是空对象占位，本函数就地填充（不新建对象——
+/// P 字段本身就是槽位，快照/脏检查/收尾枚举已覆盖）。
+///
+/// # 幂等
+/// 本函数从三条路径到达：`init_kernel_builtins`（占位是空对象）、`rebind_dirty_
+/// builtins` 的 `broadcast_channel` 分支（占位是重建后的空对象）、global-dirty
+/// 路径（占位可能已填满）。全部槽写经 `lookup_position` 前置守卫，有槽即跳过；
+/// `bind_constructor!` 的全局槽臂自带既有槽原位更新，天然幂等。
+///
+/// `realm_id` 未使用（BroadcastChannel 无 well-known 符号键），保留签名与其他
+/// 绑定函数一致。
+pub fn bind_broadcast_channel(core: &Arc<KernelCore>, session: &KernelSession, global: &mut JsObject, _realm_id: u32) {
+    let world = session.builtin_world();
+    let ctor_ptr = world.broadcast_channel_constructor.as_ptr() as *mut JsObject;
+    let ctor = unsafe { &mut *ctor_ptr };
+    let proto_ptr = world.broadcast_channel_proto.as_ptr() as *mut JsObject;
+    let proto = unsafe { &mut *proto_ptr };
+
+    let sf = core.perm_interner().as_ref();
+    let sh = core.shape_forge().as_ref();
+
+    // ---- 填构造器占位 ----
+    ctor.set_function(true);
+
+    // prototype 槽 → 原型对象（描述符 {f,f,f}）。
+    let si_prototype = sf.intern("prototype").0;
+    if sh.lookup_position(ctor.shape_id(), si_prototype).is_none() {
+        let shape = sh.make_shape(ctor.shape_id(), si_prototype);
+        ctor.set_shape_id(shape);
+        let pos = ctor.push_prop(JsValue::from_js_object(proto_ptr));
+        ctor.set_data_meta(pos, PropAttributes::new(false, false, false));
+        ctor.bump_generation();
+    }
+
+    // name 槽 → "BroadcastChannel"（描述符 {f,f,t}）。
+    let si_name = sf.intern("name").0;
+    if sh.lookup_position(ctor.shape_id(), si_name).is_none() {
+        let shape = sh.make_shape(ctor.shape_id(), si_name);
+        ctor.set_shape_id(shape);
+        ctor.ensure_hash_props()
+            .push(JsValue::perm_string(sf.string_ptr(sf.intern("BroadcastChannel").0)));
+        let pos = ctor.hash_props_vec().map_or(0, |v| v.len() as u32).saturating_sub(1);
+        ctor.set_data_meta(pos, PropAttributes::new(false, false, true));
+        ctor.bump_generation();
+    }
+
+    // [[Prototype]] → Function.prototype（幂等，裸写槽）。
+    let fn_proto_val = JsValue::from_js_object(world.function_proto.as_ptr() as *mut JsObject);
+    let _ = ctor.set_proto(fn_proto_val);
+
+    configure_native_constructor(
+        ctor,
+        oxide_builtins::broadcast_channel::broadcast_channel_constructor::<crate::vm::Vm> as *const (),
+        1,
+    );
+    bind_constructor!(
+        core,
+        global,
+        "BroadcastChannel",
+        ctor_ptr,
+        oxide_builtins::broadcast_channel::broadcast_channel_constructor::<crate::vm::Vm>,
+        1,
+        hash: true
+    );
+
+    // ---- 填原型占位 ----
+    // constructor 槽 → 构造器对象（描述符 {t,f,t}）。
+    let si_constructor = sf.intern("constructor").0;
+    if sh.lookup_position(proto.shape_id(), si_constructor).is_none() {
+        let shape = sh.make_shape(proto.shape_id(), si_constructor);
+        proto.set_shape_id(shape);
+        let pos = proto.push_prop(JsValue::from_js_object(ctor_ptr));
+        proto.set_data_meta(pos, PropAttributes::new(true, false, true));
+        proto.bump_generation();
+    }
+
+    // [[Prototype]] → Object.prototype（幂等，裸写槽）。
+    let object_proto_val = JsValue::from_js_object(world.object_proto.as_ptr() as *mut JsObject);
+    let _ = proto.set_proto(object_proto_val);
+
+    // 原型方法：postMessage / close（每方法先 lookup_position 守卫）。
+    let si_post_message = sf.intern("postMessage").0;
+    if sh.lookup_position(proto.shape_id(), si_post_message).is_none() {
+        apply_binding_table(
+            world,
+            proto,
+            core,
+            &[
+                (
+                    "postMessage",
+                    oxide_builtins::broadcast_channel::broadcast_channel_post_message::<crate::vm::Vm> as *const (),
+                    1,
+                ),
+                (
+                    "close",
+                    oxide_builtins::broadcast_channel::broadcast_channel_close::<crate::vm::Vm> as *const (),
+                    0,
+                ),
+            ],
+        );
+    }
+
+    // name 原型访问器（set 恒 undefined），lookup_position 守卫。
+    let si_name_proto = sf.intern("name").0;
+    if sh.lookup_position(proto.shape_id(), si_name_proto).is_none() {
+        bind_accessor_getter(
+            core,
+            session,
+            proto,
+            "name",
+            oxide_builtins::broadcast_channel::broadcast_channel_name::<crate::vm::Vm> as *const (),
+        );
+    }
+
+    // readyState 原型访问器（set 恒 undefined），lookup_position 守卫。
+    let si_ready_state = sf.intern("readyState").0;
+    if sh.lookup_position(proto.shape_id(), si_ready_state).is_none() {
+        bind_accessor_getter(
+            core,
+            session,
+            proto,
+            "readyState",
+            oxide_builtins::broadcast_channel::broadcast_channel_ready_state::<crate::vm::Vm> as *const (),
+        );
+    }
+}

crates/oxide_vm/src/bindings/mod.rs

@@ -14,6 +14,8 @@ pub mod bind_atomics;
 pub mod bind_bigint;
 /// Boolean 构造器与原型的 native 方法绑定。
 pub mod bind_boolean;
+/// BroadcastChannel 构造器与原型方法的 native 绑定（就地填充占位）。
+pub mod bind_broadcast_channel;
 /// Console 单例对象及其方法绑定。
 pub mod bind_console;
 /// DataView 构造器与原型的 native 方法绑定。
@@ -1057,6 +1059,11 @@ pub fn bind_global_builtin_slots(
         oxide_builtins::message_channel::message_channel_constructor::<crate::vm::Vm> as *const (),
         0,
     );
+    configure_existing_ctor(
+        &world.broadcast_channel_constructor,
+        oxide_builtins::broadcast_channel::broadcast_channel_constructor::<crate::vm::Vm> as *const (),
+        1,
+    );
 
     for (name, value) in [
         ("Object", JsValue::from_js_object(world.object_constructor.as_ptr() as *mut JsObject)),
@@ -1084,6 +1091,10 @@ pub fn bind_global_builtin_slots(
             "MessageChannel",
             JsValue::from_js_object(world.message_channel_constructor.as_ptr() as *mut JsObject),
         ),
+        (
+            "BroadcastChannel",
+            JsValue::from_js_object(world.broadcast_channel_constructor.as_ptr() as *mut JsObject),
+        ),
         ("Math", JsValue::from_js_object(world.math_object.as_ptr() as *mut JsObject)),
         ("JSON", JsValue::from_js_object(world.json_object.as_ptr() as *mut JsObject)),
         ("Temporal", JsValue::from_js_object(world.temporal_object.as_ptr() as *mut JsObject)),
@@ -1326,6 +1337,9 @@ pub fn rebind_dirty_builtins(
     if dirty.map_or(true, |d| d.message_channel) {
         bind_message_channel::bind_message_channel(core, session, global, realm_id);
     }
+    if dirty.map_or(true, |d| d.broadcast_channel) {
+        bind_broadcast_channel::bind_broadcast_channel(core, session, global, realm_id);
+    }
     if dirty.map_or(true, |d| d.console) {
         bind_console::bind_console(core, session, global);
     }

crates/oxide_vm/src/session_gc.rs

@@ -676,6 +676,24 @@ impl SessionGc {
             }
         }
 
+        // 注册表剪枝：按 mark 位移除死通道对象（此刻全部对象仍分配、位域可读，
+        // 与弱键定夺同时序）。死通道对象在随后的分流循环被释放，注册表已先移除
+        // 其条目，无悬垂；空列表删键。
+        for channels in vm.realm.gc.borrow_mut().broadcast_channels.values_mut() {
+            channels.retain(|&ptr| {
+                if ptr.is_null() {
+                    return false;
+                }
+                // SAFETY: ptr 来自 session 对象表登记，sweep 运行期间有效。
+                unsafe { (*ptr).is_gc_marked() }
+            });
+        }
+        vm.realm
+            .gc
+            .borrow_mut()
+            .broadcast_channels
+            .retain(|_, channels| !channels.is_empty());
+
         // 按 mark 位分流：存活保留清位，死对象释放本体、堆区与 upvalue 出表。
         let mut dead = 0u64;
         let mut freed_bytes = 0u64;