Switch to ThinVec

boa_engine/src/vm/call_frame/mod.rs

@@ -2,14 +2,16 @@
 //!
 //! This module will provides everything needed to implement the `CallFrame`
 
-use crate::{object::JsObject, vm::CodeBlock};
-use boa_gc::{Finalize, Gc, Trace};
-
 mod abrupt_record;
 mod env_stack;
 
+use crate::{object::JsObject, vm::CodeBlock};
+use boa_gc::{Finalize, Gc, Trace};
+use thin_vec::ThinVec;
+
 pub(crate) use abrupt_record::AbruptCompletionRecord;
 pub(crate) use env_stack::EnvStackEntry;
+
 /// A `CallFrame` holds the state of a function call.
 #[derive(Clone, Debug, Finalize, Trace)]
 pub struct CallFrame {
@@ -35,7 +37,7 @@ pub struct CallFrame {
     pub(crate) async_generator: Option<JsObject>,
 
     // Iterators and their `[[Done]]` flags that must be closed when an abrupt completion is thrown.
-    pub(crate) iterators: Vec<(JsObject, bool)>,
+    pub(crate) iterators: ThinVec<(JsObject, bool)>,
 }
 
 /// ---- `CallFrame` creation methods ----
@@ -55,7 +57,7 @@ impl CallFrame {
             arg_count: 0,
             generator_resume_kind: GeneratorResumeKind::Normal,
             async_generator: None,
-            iterators: Vec::new(),
+            iterators: ThinVec::new(),
         }
     }
 

boa_engine/src/vm/opcode/control_flow/throw.rs

@@ -3,6 +3,7 @@ use crate::{
     vm::{call_frame::AbruptCompletionRecord, opcode::Operation, CompletionType},
     Context, JsError, JsNativeError, JsResult,
 };
+use thin_vec::ThinVec;
 
 /// `Throw` implements the Opcode Operation for `Opcode::Throw`
 ///
@@ -23,7 +24,7 @@ impl Operation for Throw {
         };
 
         // Close all iterators that are still open.
-        let mut iterators = Vec::new();
+        let mut iterators = ThinVec::new();
         std::mem::swap(&mut iterators, &mut context.vm.frame_mut().iterators);
         for (iterator, done) in iterators {
             if done {