mirror of
https://github.com/pjh456/OxideJS.git
synced 2026-10-24 02:31:13 +08:00
310 lines
11 KiB
Rust
310 lines
11 KiB
Rust
use std::collections::HashMap;
|
|
use std::sync::atomic::{AtomicBool, AtomicU32, Ordering};
|
|
use std::sync::{Arc, RwLock};
|
|
|
|
use dashmap::DashMap;
|
|
|
|
use crate::{kernel_debug, kernel_trace};
|
|
|
|
/// 隐藏类（shape）的整数标识符。
|
|
pub type ShapeId = u32;
|
|
/// 属性名在字符串 intern 表（[`crate::string_forge::PermInterner`]）中的 id。
|
|
pub type StringIndex = u32;
|
|
|
|
/// 空 shape 的保留 id：表示"无属性"的根节点，构造对象时以此为初始 shape。
|
|
pub const EMPTY_SHAPE_ID: ShapeId = 1;
|
|
const EMPTY_SENTINEL: StringIndex = u32::MAX;
|
|
|
|
/// 单个隐藏类节点：记录新增的属性名、父节点与根到自身的深度。
|
|
///
|
|
/// shape 构成一棵树，从根（[`EMPTY_SHAPE_ID`]）出发每添加一个属性产生一个子节点；
|
|
/// `depth` 即该节点的属性总数。
|
|
#[derive(Debug, Clone)]
|
|
pub struct Shape {
|
|
pub id: ShapeId,
|
|
pub property_name: StringIndex,
|
|
pub parent: Option<ShapeId>,
|
|
/// 从根到本 shape 的非哨兵属性数。
|
|
pub depth: u32,
|
|
}
|
|
|
|
/// 共享隐藏类存储。
|
|
///
|
|
/// 并发模型：
|
|
/// - `shapes` 以追加为主，受 `RwLock` 保护。
|
|
/// - `transitions` 是以 `(parent_shape, property_name)` 为键的分片 `DashMap`。
|
|
/// - `positions` 缓存 `(shape_id, prop_name) → slot`，供 O(1) 重复查询。
|
|
/// - 分片数固定，保证跨机器的争用行为可复现，不依赖 DashMap 的 CPU 相关默认值。
|
|
pub struct ShapeForge {
|
|
shapes: RwLock<Vec<Option<Arc<Shape>>>>,
|
|
transitions: DashMap<u64, ShapeId>,
|
|
positions: DashMap<u64, u32>,
|
|
next_id: AtomicU32,
|
|
overflow_map: RwLock<HashMap<u64, ShapeId>>,
|
|
overflow_active: AtomicBool,
|
|
}
|
|
|
|
impl ShapeForge {
|
|
/// 创建空 forge，并预置 [`EMPTY_SHAPE_ID`] 根节点。
|
|
pub fn new() -> Self {
|
|
let forge = Self {
|
|
shapes: RwLock::new(Vec::with_capacity(256)),
|
|
transitions: DashMap::with_capacity_and_shard_amount(256, 16),
|
|
positions: DashMap::with_capacity_and_shard_amount(256, 16),
|
|
next_id: AtomicU32::new(2),
|
|
overflow_map: RwLock::new(HashMap::new()),
|
|
overflow_active: AtomicBool::new(false),
|
|
};
|
|
{
|
|
let mut shapes = forge.shapes.write().unwrap();
|
|
let empty = Arc::new(Shape {
|
|
id: EMPTY_SHAPE_ID,
|
|
property_name: EMPTY_SENTINEL,
|
|
parent: None,
|
|
depth: 0,
|
|
});
|
|
debug_assert_eq!(shapes.len(), 0);
|
|
shapes.push(Some(empty));
|
|
}
|
|
forge
|
|
}
|
|
|
|
/// 把 `(parent_shape, prop_name)` 打包为单个 u64 key，用作 transition / position 缓存的键。
|
|
pub fn pack_key(parent_id: ShapeId, prop_name: StringIndex) -> u64 {
|
|
((parent_id as u64) << 32) | (prop_name as u64)
|
|
}
|
|
|
|
/// 取（或创建）`parent_id` 加属性 `prop_name` 对应的 shape id，实现哈希一致性。
|
|
///
|
|
/// 相同 `(parent, prop_name)` 组合返回同一 id；超过 24 位上限后转入 overflow map 兜底。
|
|
pub fn make_shape(&self, parent_id: ShapeId, prop_name: StringIndex) -> ShapeId {
|
|
let key = Self::pack_key(parent_id, prop_name);
|
|
|
|
kernel_trace!("ShapeForge lookup: parent={} prop={}", parent_id, prop_name);
|
|
|
|
if let Some(entry) = self.transitions.get(&key) {
|
|
kernel_debug!("ShapeForge transition cached parent={} prop={} -> id={}", parent_id, prop_name, *entry);
|
|
return *entry;
|
|
}
|
|
|
|
if self.overflow_active.load(Ordering::Relaxed) {
|
|
if let Some(id) = self.overflow_map.read().unwrap().get(&key) {
|
|
kernel_debug!("ShapeForge overflow cached parent={} prop={} -> id={}", parent_id, prop_name, *id);
|
|
return *id;
|
|
}
|
|
}
|
|
|
|
let new_id = self.next_id.fetch_add(1, Ordering::Relaxed);
|
|
debug_assert!(new_id <= 0x00FF_FFFF, "shape_id {} exceeds 24-bit limit (16M)", new_id,);
|
|
|
|
if new_id > 0x00FF_FFFF {
|
|
self.overflow_active.store(true, Ordering::Relaxed);
|
|
let mut map = self.overflow_map.write().unwrap();
|
|
if let Some(id) = map.get(&key) {
|
|
return *id;
|
|
}
|
|
map.insert(key, new_id);
|
|
kernel_debug!("ShapeForge overflow parent={} prop={} -> id={}", parent_id, prop_name, new_id);
|
|
return new_id;
|
|
}
|
|
|
|
// 从父节点计算深度（O(1)——只读缓存值）。
|
|
let parent_depth = {
|
|
let shapes = self.shapes.read().unwrap();
|
|
shapes
|
|
.get((parent_id - 1) as usize)
|
|
.and_then(|s| s.as_ref())
|
|
.map(|s| s.depth)
|
|
.unwrap_or(0)
|
|
};
|
|
|
|
let shape = Arc::new(Shape {
|
|
id: new_id,
|
|
property_name: prop_name,
|
|
parent: Some(parent_id),
|
|
depth: parent_depth + 1,
|
|
});
|
|
|
|
{
|
|
let mut shapes = self.shapes.write().unwrap();
|
|
while shapes.len() < new_id as usize {
|
|
shapes.push(None);
|
|
}
|
|
shapes[(new_id - 1) as usize] = Some(shape);
|
|
}
|
|
|
|
let entry = self.transitions.entry(key).or_insert(new_id);
|
|
let id = *entry.value();
|
|
if id == new_id {
|
|
kernel_debug!("ShapeForge transition parent={} prop={} -> id={}", parent_id, prop_name, new_id);
|
|
} else {
|
|
kernel_debug!("ShapeForge transition cached parent={} prop={} -> id={}", parent_id, prop_name, id);
|
|
}
|
|
id
|
|
}
|
|
|
|
/// 按 id 取出 shape 节点的 `Arc` 副本；id 不存在时返回 `None`。
|
|
pub fn get_shape(&self, id: ShapeId) -> Option<Arc<Shape>> {
|
|
let shapes = self.shapes.read().unwrap();
|
|
shapes.get((id - 1) as usize).and_then(|s| s.clone())
|
|
}
|
|
|
|
/// 当前登记在册的 shape 节点数（含根节点）。
|
|
pub fn len(&self) -> usize {
|
|
self.shapes.read().unwrap().len()
|
|
}
|
|
|
|
/// 是否尚无任何 shape（正常情况下始终为 false，因根节点恒存在）。
|
|
pub fn is_empty(&self) -> bool {
|
|
self.len() == 0
|
|
}
|
|
|
|
/// 清空所有非根 shape、transition、position 缓存与 overflow 态，id 计数器复位。
|
|
///
|
|
/// 用于 session 重建：丢弃一次性对象产生的形状，只保留跨 session 共享的根节点。
|
|
/// overflow 态一并复位（不清则旧 overflow 条目把 key 映射回已被截断的 id，
|
|
/// 造成静默错深度与去重失效），id 空间完整复位。
|
|
pub fn clear_transient(&self) {
|
|
let mut shapes = self.shapes.write().unwrap();
|
|
if shapes.len() > 1 {
|
|
shapes.truncate(1);
|
|
}
|
|
drop(shapes);
|
|
self.transitions.clear();
|
|
self.positions.clear();
|
|
self.overflow_active.store(false, Ordering::Relaxed);
|
|
self.overflow_map.write().unwrap().clear();
|
|
self.next_id.store(2, Ordering::Relaxed);
|
|
}
|
|
|
|
/// 查询属性在给定 shape 对应对象存储中的槽位下标；沿父链上溯查找并缓存结果。
|
|
pub fn lookup_position(&self, shape_id: ShapeId, prop_name: StringIndex) -> Option<u32> {
|
|
let cache_key = Self::pack_key(shape_id, prop_name);
|
|
if let Some(pos) = self.positions.get(&cache_key) {
|
|
return Some(*pos);
|
|
}
|
|
|
|
let shapes = self.shapes.read().unwrap();
|
|
let root = shapes.get((shape_id - 1) as usize)?.as_ref()?;
|
|
let total_depth = root.depth;
|
|
let mut prop_steps: u32 = 0;
|
|
let mut cursor = Some(shape_id);
|
|
while let Some(id) = cursor {
|
|
let s = shapes.get((id - 1) as usize).and_then(|s| s.clone())?;
|
|
if s.property_name != EMPTY_SENTINEL {
|
|
if s.property_name == prop_name {
|
|
let pos = total_depth.checked_sub(prop_steps + 1)?;
|
|
drop(shapes);
|
|
self.positions.insert(cache_key, pos);
|
|
return Some(pos);
|
|
}
|
|
prop_steps += 1;
|
|
}
|
|
cursor = s.parent;
|
|
}
|
|
None
|
|
}
|
|
|
|
/// 判断 shape 或其祖先链上是否存在指定属性。
|
|
pub fn has_property(&self, shape_id: ShapeId, prop_name: StringIndex) -> bool {
|
|
let shapes = self.shapes.read().unwrap();
|
|
let mut cursor = Some(shape_id);
|
|
while let Some(id) = cursor {
|
|
match shapes.get((id - 1) as usize).and_then(|s| s.clone()) {
|
|
Some(s) => {
|
|
if s.property_name == prop_name && s.property_name != EMPTY_SENTINEL {
|
|
return true;
|
|
}
|
|
cursor = s.parent;
|
|
}
|
|
None => return false,
|
|
}
|
|
}
|
|
false
|
|
}
|
|
|
|
/// 返回 shape 的属性数量（即根到该节点的深度）；未知 id 返回 0。
|
|
pub fn shape_prop_count(&self, shape_id: ShapeId) -> u32 {
|
|
let shapes = self.shapes.read().unwrap();
|
|
shapes
|
|
.get((shape_id - 1) as usize)
|
|
.and_then(|s| s.as_ref())
|
|
.map(|s| s.depth)
|
|
.unwrap_or(0)
|
|
}
|
|
}
|
|
|
|
impl Default for ShapeForge {
|
|
fn default() -> Self {
|
|
Self::new()
|
|
}
|
|
}
|
|
|
|
#[cfg(test)]
|
|
mod tests {
|
|
use super::*;
|
|
use std::sync::Barrier;
|
|
|
|
/// overflow 态复位：曾触发 overflow 后 `clear_transient` 须一并清空 overflow
|
|
/// 标志与 overflow 映射，后续 `make_shape` 从新空间取小 id 而非旧映射 id。
|
|
#[test]
|
|
fn clear_transient_resets_overflow_state() {
|
|
let forge = ShapeForge::new();
|
|
let key = ShapeForge::pack_key(EMPTY_SHAPE_ID, 1_000_500);
|
|
forge.overflow_active.store(true, Ordering::Relaxed);
|
|
forge.overflow_map.write().unwrap().insert(key, 0xDEAD);
|
|
|
|
forge.clear_transient();
|
|
|
|
assert!(!forge.overflow_active.load(Ordering::Relaxed));
|
|
assert!(forge.overflow_map.read().unwrap().is_empty());
|
|
let id = forge.make_shape(EMPTY_SHAPE_ID, 1_000_500);
|
|
assert_eq!(id, 2);
|
|
}
|
|
|
|
#[test]
|
|
#[cfg_attr(debug_assertions, should_panic(expected = "exceeds 24-bit"))]
|
|
fn overflow_debug_assert_fires() {
|
|
let forge = ShapeForge::new();
|
|
forge.next_id.store(0x0100_0000, Ordering::Relaxed);
|
|
let _ = forge.make_shape(EMPTY_SHAPE_ID, 1_000_400);
|
|
}
|
|
|
|
#[test]
|
|
fn overflow_fallback_works() {
|
|
let forge = ShapeForge::new();
|
|
let key = ShapeForge::pack_key(EMPTY_SHAPE_ID, 1_000_500);
|
|
forge.overflow_active.store(true, Ordering::Relaxed);
|
|
forge.overflow_map.write().unwrap().insert(key, 0xDEAD);
|
|
let id = forge.make_shape(EMPTY_SHAPE_ID, 1_000_500);
|
|
assert_eq!(id, 0xDEAD);
|
|
}
|
|
|
|
#[test]
|
|
fn overflow_concurrent_same_key() {
|
|
let forge = Arc::new(ShapeForge::new());
|
|
let key: StringIndex = 1_000_600;
|
|
forge.overflow_active.store(true, Ordering::Relaxed);
|
|
let barrier = Arc::new(Barrier::new(2));
|
|
|
|
let f1 = Arc::clone(&forge);
|
|
let b1 = Arc::clone(&barrier);
|
|
let h1 = std::thread::spawn(move || {
|
|
b1.wait();
|
|
f1.make_shape(EMPTY_SHAPE_ID, key)
|
|
});
|
|
|
|
let f2 = Arc::clone(&forge);
|
|
let b2 = Arc::clone(&barrier);
|
|
let h2 = std::thread::spawn(move || {
|
|
b2.wait();
|
|
f2.make_shape(EMPTY_SHAPE_ID, key)
|
|
});
|
|
|
|
let id1 = h1.join().unwrap();
|
|
let id2 = h2.join().unwrap();
|
|
assert_eq!(id1, id2);
|
|
assert!(id1 > 0);
|
|
}
|
|
}
|