mirror of
https://github.com/pjh456/OxideJS.git
synced 2026-10-24 02:31:13 +08:00
82 lines
3.7 KiB
Rust
82 lines
3.7 KiB
Rust
//! 内联同步执行核心的堆上快照 `InlineSyncState`；字段登记表宏
|
||
//! `inline_core_fields!` 在 `vm_runtime` 模块。
|
||
|
||
use std::sync::Arc;
|
||
|
||
use oxide_bytecode::opcode;
|
||
use oxide_types::object::Cell;
|
||
use oxide_types::value::JsValue;
|
||
use smallvec::SmallVec;
|
||
|
||
use super::frames::{CallFrame, Completion, ForInIter, TryHandler};
|
||
use crate::vm_state::ForOfEntry;
|
||
|
||
/// `call_bytecode_function_inline` 使用的堆分配快照。
|
||
/// 放在堆上避免 JS 代码链式同步字节码调用（如 sort 比较器、accessor）时
|
||
/// 耗尽 Rust 栈。
|
||
pub(crate) struct InlineSyncState {
|
||
/// 寄存器窗口副本：`regs[0..len]`，len ≤ 254（含 RegAlloc 最高合法物理槽
|
||
/// 253）。`regs[254]/[255]` 不在此列，由 `saved_this`/`saved_new_target`
|
||
/// 单独保存（callee 也会重写这两个槽）。
|
||
pub(crate) regs: Box<[JsValue]>,
|
||
pub(crate) saved_this: JsValue,
|
||
pub(crate) saved_new_target: JsValue,
|
||
pub(crate) pc: usize,
|
||
pub(crate) bytecode: Arc<[opcode::Instr]>,
|
||
pub(crate) active_immutables: *const [JsValue],
|
||
pub(crate) active_reg_limit: u8,
|
||
pub(crate) root_reg_limit: u8,
|
||
pub(crate) try_stack: Vec<TryHandler>,
|
||
pub(crate) frames: SmallVec<[CallFrame; 16]>,
|
||
pub(crate) exception_value: Option<JsValue>,
|
||
pub(crate) pending_exception: Option<JsValue>,
|
||
pub(crate) pending_error_kind: Option<&'static str>,
|
||
pub(crate) pending_completion: Option<Completion>,
|
||
pub(crate) for_in_iters: Vec<*mut ForInIter>,
|
||
pub(crate) for_of_iters: Vec<ForOfEntry>,
|
||
pub(crate) saved_bytecode_stack: Vec<Arc<[opcode::Instr]>>,
|
||
pub(crate) saved_immutables_stack: Vec<*const [JsValue]>,
|
||
pub(crate) save_stack: Vec<JsValue>,
|
||
pub(crate) spill_stack: Vec<JsValue>,
|
||
pub(crate) cell_stack: Vec<Vec<*mut Cell>>,
|
||
pub(crate) inline_callee: Option<JsValue>,
|
||
/// 当前执行函数的 upvalue cell 表镜像（与 `inline_callee` 同生命周期，
|
||
/// 随本快照保存/恢复）。
|
||
pub(crate) active_upvalues: *const [*mut Cell],
|
||
/// 三个内嵌 dispatch 调度标志（`Vm::generator_dispatch` / `async_dispatch` /
|
||
/// `construct_dispatch`）的属主快照。save 时记录外层值并清零 VM 侧、restore
|
||
/// 时写回：嵌套 state-swap 调用不得继承外层调度上下文，否则其内部构造帧
|
||
/// 弹出后 frames 清空，`do_return` 会把嵌套调用误判为属主内嵌 dispatch 提前
|
||
/// 交付，跳过被调函数剩余字节码（详见 `do_return` 交付条件注释）。
|
||
pub(crate) generator_dispatch: bool,
|
||
pub(crate) async_dispatch: bool,
|
||
pub(crate) construct_dispatch: bool,
|
||
/// inline 目标函数的严格模式标志（内联执行期间写路径的 strict/sloppy 判定
|
||
/// 来源；嵌套内联时随本快照保存/恢复）。
|
||
pub(crate) inline_strict: bool,
|
||
/// inline 起始时 `frames.len()` 基线（嵌套内联时随本快照保存/恢复）。
|
||
pub(crate) inline_frames_base: usize,
|
||
pub(crate) inline_args_base: u32,
|
||
pub(crate) inline_args_count: u16,
|
||
pub(crate) accessor_frame_target_reg: Option<u8>,
|
||
pub(crate) active_flat_id: u32,
|
||
pub(crate) active_table_gen: u32,
|
||
}
|
||
|
||
impl Drop for InlineSyncState {
|
||
/// 释放快照持有的 for-in 迭代器体：体是堆上 `Box`，快照独占持有自身体，
|
||
/// drop 时逐条释放（null 跳过）。restore 是字段直移，移出后字段为空，
|
||
/// Drop 不再触碰，无双放。
|
||
fn drop(&mut self) {
|
||
for iter in self.for_in_iters.drain(..) {
|
||
if iter.is_null() {
|
||
continue;
|
||
}
|
||
// SAFETY: 指针是堆上迭代器体，快照独占持有，释放恰好一次。
|
||
unsafe {
|
||
drop(Box::from_raw(iter));
|
||
}
|
||
}
|
||
}
|
||
}
|