Struct Heap

#[repr(C)]
pub struct Heap { /* private fields */ }

Comet heap. It stores all the required global data:

• GlobalAllocator instance
• Callbacks that are run before GC cycle
• Threshold and allocations of current GC cycle
• Number of deferred GC cycles
• Weak references

Implementations

impl Heap

pub fn for_each_cell( &mut self, callback: impl FnMut(*mut HeapObjectHeader), weak_refs: impl FnMut(GcRef<WeakSlot>), )

This function will iterate through each object allocated in heap. Separate callbacks are used for weak refs and regular objects.

NOTE: callback for regular object might receive weak ref pointer in it too.

pub fn add_constraint(&mut self, constraint: impl MarkingConstraint + 'static)

Adds GC constraint into constraints vector. Each constraint is ran before GC cycle.

pub fn add_core_constraints(&mut self)

Adds core GC constraints into constraint vector. For now it is just conservative stack marking constraint.

pub fn new(config: Config) -> Box<Heap>

Creates new heap instance with configuration from config.

pub fn collect_garbage(&mut self)

Force collect garbage. If GC is deferred nothing will happen.

pub fn collect_if_necessary_or_defer(&mut self)

Collects garbage if necessary i.e allocates bytes are greater than threshold.

pub unsafe fn allocate_weak(&mut self, target: UntypedGcRef) -> WeakGcRef

Allocate weak reference for specified GC pointer.

pub unsafe fn allocate_raw( &mut self, size: usize, index: GCInfoIndex, ) -> Option<UntypedGcRef>

Allocate “raw” memory. This memory is not initialized at all (except header part of UntypedGcRef).

• size should include size for object you’re allocating and additional bytes for HeapObjectHeader. If it is embedded in your struct as first field you do not have to include that.
• index should be an index obtained by calling T::index() on type that implements GCInfoTrait

This function returns none if allocation is failed.

pub unsafe fn allocate_raw_or_fail( &mut self, size: usize, index: GCInfoIndex, ) -> UntypedGcRef

Same as Heap::allocate_raw except it will try to perform GC cycle and if GC does not free enough memory it will abort.

Trait Implementations

impl Drop for Heap

fn drop(&mut self)

Executes the destructor for this type.