减少策略股票状态的字符串分配

crates/fidc-core/src/data.rs

@@ -1332,6 +1332,9 @@ pub struct DataSet {
     market_series_end_positions_by_symbol_id: Arc<Option<SymbolSeriesEndPositionIndex>>,
     benchmark_series_cache: Arc<BenchmarkPriceSeries>,
     symbol_id_by_code: Arc<AHashMap<String, u32>>,
+    /// Interned symbol text indexed by immutable symbol id so per-day
+    /// expression states can share the same allocation.
+    symbol_text_by_id: Arc<Vec<Arc<str>>>,
     eligible_universe_by_date: Arc<OnceLock<BTreeMap<NaiveDate, Vec<EligibleUniverseSnapshot>>>>,
     benchmark_code: String,
     futures_params_by_symbol: Arc<HashMap<String, Vec<FuturesTradingParameter>>>,
@@ -1737,6 +1740,12 @@ impl DataSet {
             &factor_by_date,
             &candidate_by_date,
         );
+        let mut symbol_text_by_id = vec![Arc::<str>::from(""); symbol_id_by_code.len()];
+        for (symbol, symbol_id) in &symbol_id_by_code {
+            if let Some(slot) = symbol_text_by_id.get_mut(*symbol_id as usize) {
+                *slot = Arc::<str>::from(symbol.as_str());
+            }
+        }
         let market_symbol_ids_by_date =
             build_group_symbol_ids(&market_by_date, &symbol_id_by_code, |item| {
                 item.symbol.as_str()
@@ -1815,6 +1824,7 @@ impl DataSet {
             ),
             benchmark_series_cache: Arc::new(benchmark_series_cache),
             symbol_id_by_code: Arc::new(symbol_id_by_code),
+            symbol_text_by_id: Arc::new(symbol_text_by_id),
             eligible_universe_by_date: Arc::new(OnceLock::new()),
             benchmark_code,
             futures_params_by_symbol: Arc::new(futures_params_by_symbol),
@@ -1862,6 +1872,10 @@ impl DataSet {
         self.symbol_id_by_code.get(symbol).copied()
     }
 
+    pub(crate) fn symbol_text_by_id(&self, symbol_id: u32) -> Option<&Arc<str>> {
+        self.symbol_text_by_id.get(symbol_id as usize)
+    }
+
     pub fn market(&self, date: NaiveDate, symbol: &str) -> Option<&DailyMarketSnapshot> {
         let symbol_id = self.symbol_id(symbol)?;
         self.market_by_symbol_id(date, symbol_id)

crates/fidc-core/src/platform_expr_strategy.rs

@@ -656,7 +656,7 @@ struct DayExpressionState {
 
 #[derive(Debug, Clone)]
 struct StockExpressionState {
-    symbol: String,
+    symbol: Arc<str>,
     symbol_id: u32,
     market_cap: f64,
     market_cap_bn: f64,
@@ -4169,7 +4169,17 @@ impl PlatformExprStrategy {
         };
 
         let state = Arc::new(StockExpressionState {
-            symbol: symbol.to_string(),
+            symbol: ctx
+                .data
+                .symbol_text_by_id(symbol_id)
+                .cloned()
+                .ok_or_else(|| {
+                    BacktestError::Data(crate::data::DataSetError::MissingSnapshot {
+                        kind: "symbol_text_index",
+                        date,
+                        symbol: symbol.to_string(),
+                    })
+                })?,
             symbol_id,
             market_cap,
             market_cap_bn,
@@ -4640,7 +4650,7 @@ impl PlatformExprStrategy {
                 stock.lower_limit,
                 stock.price_tick,
             );
-            scope.push("symbol", stock.symbol.clone());
+            scope.push("symbol", stock.symbol.as_ref());
             scope.push("market_cap", stock.market_cap);
             scope.push("market_cap_bn", stock.market_cap_bn);
             scope.push("free_float_cap", stock.free_float_cap);
@@ -4739,7 +4749,10 @@ impl PlatformExprStrategy {
             scope.push("volume_ma100", stock.stock_volume_ma100);
             if include_factors_map {
                 let mut factors = Map::new();
-                factors.insert("symbol".into(), Dynamic::from(stock.symbol.clone()));
+                factors.insert(
+                    "symbol".into(),
+                    Dynamic::from(stock.symbol.as_ref().to_string()),
+                );
                 factors.insert("market_cap".into(), Dynamic::from(stock.market_cap));
                 factors.insert("market_cap_bn".into(), Dynamic::from(stock.market_cap_bn));
                 factors.insert("free_float_cap".into(), Dynamic::from(stock.free_float_cap));
@@ -6586,7 +6599,7 @@ impl PlatformExprStrategy {
                 let matched = ctx
                     .get_margin_stocks(&margin_type)
                     .iter()
-                    .any(|symbol| symbol == &stock.symbol);
+                    .any(|symbol| symbol.as_str() == stock.symbol.as_ref());
                 Ok(RuntimeHelperResolution::Boolean(matched))
             }
             "dominant_future" | "get_dominant_future" => {
@@ -6656,14 +6669,14 @@ impl PlatformExprStrategy {
             let stock = stock.ok_or_else(|| {
                 BacktestError::Execution(format!("{helper} requires stock context"))
             })?;
-            return Ok((stock.symbol.clone(), default_lookback));
+            return Ok((stock.symbol.as_ref().to_string(), default_lookback));
         }
         if args.len() == 1 {
             if let Ok(lookback) = Self::parse_positive_usize(&args[0]) {
                 let stock = stock.ok_or_else(|| {
                     BacktestError::Execution(format!("{helper} requires stock context"))
                 })?;
-                return Ok((stock.symbol.clone(), lookback));
+                return Ok((stock.symbol.as_ref().to_string(), lookback));
             }
             return Ok((
                 Self::parse_string_or_identifier(&args[0])?,