perf: reduce memory allocation in esm_export_imported_specifier_dependency (#10657)

* Reduce memory allocation

* Split ExportMode into variants

* Box largest

* Vec -> HashSet

* Fix Clippy

* &Option<_> to Option<&_>

Author: CPunisher

crates/rspack_core/src/artifacts/module_graph_cache_artifact.rs

@@ -157,44 +157,68 @@ pub struct NormalReexportItem {
   pub export_info: ExportInfo,
 }
 
-#[derive(Debug, PartialEq, Eq, Clone, Copy)]
-pub enum ExportModeType {
+#[derive(Debug, Clone)]
+pub enum ExportMode {
   Missing,
-  Unused,
-  EmptyStar,
-  ReexportDynamicDefault,
-  ReexportNamedDefault,
-  ReexportNamespaceObject,
-  ReexportFakeNamespaceObject,
-  ReexportUndefined,
-  NormalReexport,
-  DynamicReexport,
+  Unused(ExportModeUnused),
+  EmptyStar(ExportModeEmptyStar),
+  ReexportDynamicDefault(ExportModeReexportDynamicDefault),
+  ReexportNamedDefault(ExportModeReexportNamedDefault),
+  ReexportNamespaceObject(ExportModeReexportNamespaceObject),
+  ReexportFakeNamespaceObject(ExportModeFakeNamespaceObject),
+  ReexportUndefined(ExportModeReexportUndefined),
+  NormalReexport(ExportModeNormalReexport),
+  DynamicReexport(Box<ExportModeDynamicReexport>),
 }
 
 #[derive(Debug, Clone)]
-pub struct ExportMode {
-  /// corresponding to `type` field in webpack's `EpxortMode`
-  pub ty: ExportModeType,
-  pub items: Option<Vec<NormalReexportItem>>,
-  pub name: Option<Atom>,
-  pub fake_type: u8,
-  pub partial_namespace_export_info: Option<ExportInfo>,
-  pub ignored: Option<HashSet<Atom>>,
+pub struct ExportModeUnused {
+  pub name: Atom,
+}
+
+#[derive(Debug, Clone)]
+pub struct ExportModeEmptyStar {
   pub hidden: Option<HashSet<Atom>>,
 }
 
-impl ExportMode {
-  pub fn new(ty: ExportModeType) -> Self {
-    Self {
-      ty,
-      items: None,
-      name: None,
-      fake_type: 0,
-      partial_namespace_export_info: None,
-      ignored: None,
-      hidden: None,
-    }
-  }
+#[derive(Debug, Clone)]
+pub struct ExportModeReexportDynamicDefault {
+  pub name: Atom,
+}
+
+#[derive(Debug, Clone)]
+pub struct ExportModeReexportNamedDefault {
+  pub name: Atom,
+  pub partial_namespace_export_info: ExportInfo,
+}
+
+#[derive(Debug, Clone)]
+pub struct ExportModeReexportNamespaceObject {
+  pub name: Atom,
+  pub partial_namespace_export_info: ExportInfo,
+}
+
+#[derive(Debug, Clone)]
+pub struct ExportModeFakeNamespaceObject {
+  pub name: Atom,
+  pub fake_type: u8,
+  pub partial_namespace_export_info: ExportInfo,
+}
+
+#[derive(Debug, Clone)]
+pub struct ExportModeReexportUndefined {
+  pub name: Atom,
+}
+
+#[derive(Debug, Clone)]
+pub struct ExportModeNormalReexport {
+  pub items: Vec<NormalReexportItem>,
+}
+
+#[derive(Debug, Clone)]
+pub struct ExportModeDynamicReexport {
+  pub ignored: HashSet<Atom>,
+  pub hidden: Option<HashSet<Atom>>,
 }
 
 #[derive(Debug, Default)]

crates/rspack_core/src/dependency/mod.rs

@@ -37,7 +37,7 @@ pub use runtime_requirements_dependency::{
   RuntimeRequirementsDependency, RuntimeRequirementsDependencyTemplate,
 };
 pub use runtime_template::*;
-use rustc_hash::FxHashMap;
+use rustc_hash::{FxHashMap, FxHashSet};
 use serde::Serialize;
 pub use span::SpanExt;
 pub use static_exports_dependency::{StaticExportsDependency, StaticExportsSpec};
@@ -106,8 +106,8 @@ pub struct ExportsSpec {
   pub terminal_binding: Option<bool>,
   pub from: Option<ModuleGraphConnection>,
   pub dependencies: Option<Vec<ModuleIdentifier>>,
-  pub hide_export: Option<Vec<Atom>>,
-  pub exclude_exports: Option<Vec<Atom>>,
+  pub hide_export: Option<FxHashSet<Atom>>,
+  pub exclude_exports: Option<FxHashSet<Atom>>,
 }
 
 pub trait DependencyConditionFn: Sync + Send {

crates/rspack_core/src/exports/exports_info.rs

@@ -4,6 +4,7 @@ use either::Either;
 use rspack_cacheable::cacheable;
 use rspack_collections::{impl_item_ukey, Ukey, UkeySet};
 use rspack_util::atom::Atom;
+use rustc_hash::FxHashSet;
 use serde::Serialize;
 
 use super::{
@@ -129,15 +130,15 @@ impl ExportsInfo {
     &self,
     mg: &mut ModuleGraph,
     can_mangle: bool,
-    exclude_exports: Option<Vec<Atom>>,
+    exclude_exports: Option<&FxHashSet<Atom>>,
     target_key: Option<DependencyId>,
     target_module: Option<DependencyId>,
     priority: Option<u8>,
   ) -> bool {
     let mut changed = false;
 
     if let Some(exclude_exports) = &exclude_exports {
-      for name in exclude_exports {
+      for name in exclude_exports.iter() {
         self.get_export_info(mg, name);
       }
     }