perf: avoid heap allocation for getting connections (#8625)

crates/rspack_core/src/build_chunk_graph/code_splitter.rs

@@ -1567,17 +1567,13 @@ Or do you want to use the entrypoints '{name}' and '{runtime}' independently on
       map.insert(b.into(), Vec::new());
     }
 
-    let sorted_connections = module_graph
-      .get_ordered_connections(&module)
-      .expect("should have module");
-
     // keep the dependency order sorted by span
     let mut connection_map: IndexMap<
       (DependenciesBlockIdentifier, ModuleIdentifier),
       Vec<DependencyId>,
     > = IndexMap::default();
 
-    for dep_id in sorted_connections {
+    for dep_id in module_graph.get_ordered_all_dependencies(&module) {
       let dep = module_graph
         .dependency_by_id(dep_id)
         .expect("should have dep");

crates/rspack_core/src/chunk_graph/chunk_graph_module.rs

@@ -268,29 +268,23 @@ impl ChunkGraph {
       .hash(&mut hasher);
     let strict = module.get_strict_esm_module();
     let mg = compilation.get_module_graph();
-    let connections = mg
-      .get_outgoing_connections(&module.identifier())
-      .into_iter()
-      .collect::<Vec<_>>();
-    if !connections.is_empty() {
-      let mut visited_modules = IdentifierSet::default();
-      visited_modules.insert(module.identifier());
-      for connection in connections {
-        let module_identifier = connection.module_identifier();
-        if visited_modules.contains(module_identifier) {
-          continue;
-        }
-        if connection.active_state(&mg, runtime).is_false() {
-          continue;
-        }
-        visited_modules.insert(*module_identifier);
-        let module = mg
-          .module_by_identifier(module_identifier)
-          .expect("should have module")
-          .as_ref();
-        module.get_exports_type(&mg, strict).hash(&mut hasher);
-        self.get_module_graph_hash_without_connections(module, compilation, runtime);
+    let mut visited_modules = IdentifierSet::default();
+    visited_modules.insert(module.identifier());
+    for connection in mg.get_outgoing_connections(&module.identifier()) {
+      let module_identifier = connection.module_identifier();
+      if visited_modules.contains(module_identifier) {
+        continue;
       }
+      if connection.active_state(&mg, runtime).is_false() {
+        continue;
+      }
+      visited_modules.insert(*module_identifier);
+      let module = mg
+        .module_by_identifier(module_identifier)
+        .expect("should have module")
+        .as_ref();
+      module.get_exports_type(&mg, strict).hash(&mut hasher);
+      self.get_module_graph_hash_without_connections(module, compilation, runtime);
     }
     hasher.finish()
   }

crates/rspack_core/src/compiler/make/cutout/mod.rs

@@ -86,7 +86,6 @@ impl Cutout {
               res.extend(
                 module_graph
                   .get_incoming_connections(&module.identifier())
-                  .iter()
                   .filter_map(|connect| connect.original_module_identifier),
               )
             }

crates/rspack_core/src/concatenated_module.rs

@@ -154,8 +154,8 @@ impl ConcatenationEntryExternal {
 }
 
 #[derive(Debug)]
-pub struct ConcatenatedModuleImportInfo {
-  connection: ModuleGraphConnection,
+pub struct ConcatenatedModuleImportInfo<'a> {
+  connection: &'a ModuleGraphConnection,
   source_order: i32,
   range_start: Option<u32>,
 }
@@ -201,8 +201,8 @@ pub struct ExternalModuleInfo {
   pub name: Option<Atom>,
 }
 
-pub struct ConnectionWithRuntimeCondition {
-  pub connection: ModuleGraphConnection,
+pub struct ConnectionWithRuntimeCondition<'a> {
+  pub connection: &'a ModuleGraphConnection,
   pub runtime_condition: RuntimeCondition,
 }
 
@@ -1530,7 +1530,7 @@ impl ConcatenatedModule {
     module_set: &mut IdentifierIndexSet,
     runtime: Option<&RuntimeSpec>,
     mg: &ModuleGraph,
-    con: ModuleGraphConnection,
+    con: &ModuleGraphConnection,
     runtime_condition: RuntimeCondition,
     exists_entry: &mut IdentifierMap<RuntimeCondition>,
     list: &mut Vec<ConcatenationEntry>,
@@ -1592,21 +1592,17 @@ impl ConcatenatedModule {
     }
   }
 
-  fn get_concatenated_imports(
+  fn get_concatenated_imports<'a>(
     &self,
     module_id: &ModuleIdentifier,
     root_module_id: &ModuleIdentifier,
     runtime: Option<&RuntimeSpec>,
-    mg: &ModuleGraph,
-  ) -> Vec<ConnectionWithRuntimeCondition> {
-    let mut connections = mg
-      .get_outgoing_connections(module_id)
-      .into_iter()
-      .cloned()
-      .collect::<Vec<_>>();
+    mg: &'a ModuleGraph,
+  ) -> Vec<ConnectionWithRuntimeCondition<'a>> {
+    let mut connections = mg.get_outgoing_connections(module_id).collect::<Vec<_>>();
     if module_id == root_module_id {
       for c in mg.get_outgoing_connections(&self.id) {
-        connections.push(c.clone());
+        connections.push(c);
       }
     }
 

crates/rspack_core/src/incremental/mutations.rs

@@ -158,7 +158,6 @@ impl Mutations {
               updated_modules.extend(
                 module_graph
                   .get_incoming_connections(module)
-                  .into_iter()
                   .filter_map(|c| c.original_module_identifier),
               );
             }

crates/rspack_core/src/module_graph/mod.rs

@@ -3,7 +3,7 @@ use std::collections::hash_map::Entry;
 use rspack_collections::{IdentifierMap, UkeyMap};
 use rspack_error::Result;
 use rspack_hash::RspackHashDigest;
-use rustc_hash::{FxHashMap as HashMap, FxHashSet as HashSet};
+use rustc_hash::FxHashMap as HashMap;
 use swc_core::ecma::atoms::Atom;
 
 use crate::{
@@ -789,18 +789,19 @@ impl<'a> ModuleGraph<'a> {
     exports_info.get_export_info(self, export_name)
   }
 
-  pub(crate) fn get_ordered_connections(
+  pub(crate) fn get_ordered_all_dependencies(
     &self,
     module_identifier: &ModuleIdentifier,
-  ) -> Option<Vec<&DependencyId>> {
+  ) -> impl Iterator<Item = &DependencyId> {
     self
       .module_graph_module_by_identifier(module_identifier)
       .map(|m| {
         m.all_dependencies
           .iter()
           .filter(|dep_id| self.connection_by_dependency_id(dep_id).is_some())
-          .collect()
       })
+      .into_iter()
+      .flatten()
   }
 
   pub fn connection_by_dependency_id(
@@ -848,7 +849,7 @@ impl<'a> ModuleGraph<'a> {
 
   pub fn is_optional(&self, module_id: &ModuleIdentifier) -> bool {
     let mut has_connections = false;
-    for connection in self.get_incoming_connections(module_id).iter() {
+    for connection in self.get_incoming_connections(module_id) {
       let Some(dependency) = self
         .dependency_by_id(&connection.dependency_id)
         .and_then(|dep| dep.as_module_dependency())
@@ -886,33 +887,33 @@ impl<'a> ModuleGraph<'a> {
   pub fn get_outgoing_connections(
     &self,
     module_id: &ModuleIdentifier,
-  ) -> HashSet<&ModuleGraphConnection> {
+  ) -> impl Iterator<Item = &ModuleGraphConnection> + Clone {
     self
       .module_graph_module_by_identifier(module_id)
       .map(|mgm| {
         mgm
           .outgoing_connections()
           .iter()
           .filter_map(|id| self.connection_by_dependency_id(id))
-          .collect()
       })
-      .unwrap_or_default()
+      .into_iter()
+      .flatten()
   }
 
   pub fn get_incoming_connections(
     &self,
     module_id: &ModuleIdentifier,
-  ) -> HashSet<&ModuleGraphConnection> {
+  ) -> impl Iterator<Item = &ModuleGraphConnection> + Clone {
     self
       .module_graph_module_by_identifier(module_id)
       .map(|mgm| {
         mgm
           .incoming_connections()
           .iter()
           .filter_map(|id| self.connection_by_dependency_id(id))
-          .collect()
       })
-      .unwrap_or_default()
+      .into_iter()
+      .flatten()
   }
 
   pub fn get_module_hash(&self, module_id: &ModuleIdentifier) -> Option<&RspackHashDigest> {

crates/rspack_plugin_dll/src/lib_manifest_plugin.rs

@@ -111,9 +111,7 @@ async fn emit(&self, compilation: &mut Compilation) -> Result<()> {
     for module in chunk_graph.get_ordered_chunk_modules(&chunk.ukey(), &module_graph) {
       if self.options.entry_only.unwrap_or_default()
         && !some_in_iterable(
-          module_graph
-            .get_incoming_connections(&module.identifier())
-            .into_iter(),
+          module_graph.get_incoming_connections(&module.identifier()),
           |conn| {
             let dep = module_graph.dependency_by_id(&conn.dependency_id);
 

crates/rspack_plugin_javascript/src/plugin/infer_async_modules_plugin.rs

@@ -106,7 +106,6 @@ fn set_sync_modules(
     let module_graph = compilation.get_module_graph();
     if module_graph
       .get_outgoing_connections(&module)
-      .iter()
       .filter_map(|con| module_graph.module_identifier_by_dependency_id(&con.dependency_id))
       .filter(|&out| &module != out)
       .any(|module| ModuleGraph::is_async(compilation, module))
@@ -124,7 +123,6 @@ fn set_sync_modules(
       let module_graph = compilation.get_module_graph();
       module_graph
         .get_incoming_connections(&module)
-        .iter()
         .filter(|con| {
           module_graph
             .dependency_by_id(&con.dependency_id)
@@ -160,7 +158,6 @@ fn set_async_modules(
       let module_graph = compilation.get_module_graph();
       module_graph
         .get_incoming_connections(&module)
-        .iter()
         .filter(|con| {
           module_graph
             .dependency_by_id(&con.dependency_id)

crates/rspack_plugin_library/src/modern_module_library_plugin.rs

@@ -223,7 +223,7 @@ async fn finish_modules(&self, compilation: &mut Compilation) -> Result<()> {
     let mut deps_to_replace = Vec::new();
     let module = mg.module_by_identifier(module_id).expect("should have mgm");
 
-    let connections = mg.get_outgoing_connections(module_id);
+    let connections: HashSet<_> = mg.get_outgoing_connections(module_id).collect();
     let block_ids = module.get_blocks();
 
     for block_id in block_ids {
@@ -290,7 +290,7 @@ async fn finish_modules(&self, compilation: &mut Compilation) -> Result<()> {
     let mut deps_to_replace = Vec::new();
     let mut external_connections = Vec::new();
     let module = mg.module_by_identifier(module_id).expect("should have mgm");
-    let connections = mg.get_outgoing_connections(module_id);
+    let connections: HashSet<_> = mg.get_outgoing_connections(module_id).collect();
     let dep_ids = module.get_dependencies();
 
     let mut module_id_to_connections: IdentifierMap<Vec<DependencyId>> = IdentifierMap::default();

crates/rspack_plugin_warn_sensitive_module/src/lib.rs

@@ -27,17 +27,18 @@ impl WarnCaseSensitiveModulesPlugin {
 
     for m in modules {
       if let Some(boxed_m) = graph.module_by_identifier(&m) {
-        let mut module_msg = format!("  - {}\n", m);
+        message.push_str("  - ");
+        message.push_str(&m);
+        message.push('\n');
         graph
           .get_incoming_connections(&boxed_m.identifier())
-          .iter()
           .for_each(|c| {
             if let Some(original_identifier) = c.original_module_identifier {
-              module_msg.push_str(&format!("    - used by {}\n", original_identifier));
+              message.push_str("    - used by ");
+              message.push_str(&original_identifier);
+              message.push('\n');
             }
           });
-
-        message.push_str(&module_msg);
       }
     }