From 6561f41ea3ce62e08c7dffc6731b50713db916d3 Mon Sep 17 00:00:00 2001
From: Tim Peters <tim@protonomaly.nl>
Date: Tue, 28 May 2024 21:23:31 +0200
Subject: [PATCH] Automatically add finalizer.

Use needs_drop to see if the type needs to be dropped. Right now this is only .
---
 lox-gc/src/gc.rs             | 11 +++++++++--
 lox-gc/src/lib.rs            |  6 ------
 lox-vm/src/memory/closure.rs |  6 +++---
 lox-vm/src/runtime.rs        |  2 --
 4 files changed, 12 insertions(+), 13 deletions(-)

diff --git a/lox-gc/src/gc.rs b/lox-gc/src/gc.rs
index e625561..08d3963 100644
--- a/lox-gc/src/gc.rs
+++ b/lox-gc/src/gc.rs
@@ -61,7 +61,7 @@ impl ManagedHeap {
         }
     }
 
-    pub fn finalize(&self, gc: Gc<()>) {
+    fn finalize(&self, gc: Gc<()>) {
         self.finalizers.borrow_mut().push(gc);
     }
 
@@ -90,13 +90,20 @@ impl ManagedHeap {
     pub fn manage<T>(&self, data: T) -> Gc<T> where T: Trace + 'static {
         let layout = std::alloc::Layout::new::<Allocation<T>>();
         let ptr = self.heap.alloc(layout) as *mut Allocation<T>;
-        unsafe {
+        let gc = unsafe {
             ptr.write(Allocation::new(data));
 
             Gc {
                 ptr: NonNull::new_unchecked(ptr),
             }
+        };
+
+        if std::mem::needs_drop::<T>() {
+            //eprintln!("Type {} needs drop. Adding to finalizers.", std::any::type_name::<T>());
+            self.finalize(gc.erase());
         }
+
+        gc
     }
 
     pub fn collect(&self, roots: &[&dyn Trace]) {
diff --git a/lox-gc/src/lib.rs b/lox-gc/src/lib.rs
index f4ae682..03592e3 100644
--- a/lox-gc/src/lib.rs
+++ b/lox-gc/src/lib.rs
@@ -25,9 +25,3 @@ pub fn collect(roots: &[&dyn Trace]) {
         heap.collect(roots)
     })
 }
-
-pub fn finalize<T>(gc: Gc<T>) {
-    HEAP.with(|heap| {
-        heap.finalize(gc.erase())
-    })
-}
diff --git a/lox-vm/src/memory/closure.rs b/lox-vm/src/memory/closure.rs
index 1a5fbba..6a1f7a3 100644
--- a/lox-vm/src/memory/closure.rs
+++ b/lox-vm/src/memory/closure.rs
@@ -3,12 +3,12 @@ use std::cell::Cell;
 use lox_gc::{Gc, Trace, Tracer};
 use crate::memory::{Import, Upvalue};
 use crate::fiber::Fiber;
-use arrayvec::ArrayVec;
 use crate::string::LoxString;
+use crate::array::Array;
 
 pub struct Closure {
     pub function: Function,
-    pub upvalues: ArrayVec<Gc<Cell<Upvalue>>, 128>,
+    pub upvalues: Array<Gc<Cell<Upvalue>>>,
 }
 
 unsafe impl Trace for Closure {
@@ -57,7 +57,7 @@ impl Closure {
         };
 
         Closure {
-            upvalues: ArrayVec::new(),
+            upvalues: Array::new(),
             function,
         }
     }
diff --git a/lox-vm/src/runtime.rs b/lox-vm/src/runtime.rs
index adbbcf8..b19ba43 100644
--- a/lox-vm/src/runtime.rs
+++ b/lox-vm/src/runtime.rs
@@ -122,7 +122,6 @@ impl Runtime {
     fn prepare_interpret(&mut self, module: Module) -> Gc<Closure> {
         let import = Import::with_module("_root", module, &mut self.interner);
         let import: Gc<Import> = self.manage(import.into());
-        lox_gc::finalize(import);
         self.imports.insert(import.name.clone(), import);
         self.globals_import().copy_to(&import);
 
@@ -142,7 +141,6 @@ impl Runtime {
         if let Some(module) = module {
             let import = Import::with_module(path, module, &mut self.interner);
             let import = self.manage(import.into());
-            lox_gc::finalize(import);
             self.imports.insert(path.into(), import);
             self.globals_import().copy_to(&import);