Struct TensorGarbageCollector 

pub struct TensorGarbageCollector {
    pub tensors: HashMap<u64, TensorRef>,
    pub roots: Vec<u64>,
}

Mark-and-sweep garbage collector for tensor allocations.

Tracks a set of TensorRef descriptors connected by dependency edges, and periodically reclaims those that are unreachable from the named root set and carry no external references.

Fields

tensors: HashMap<u64, TensorRef>

All registered tensor descriptors keyed by tensor_id.

roots: Vec<u64>

Tensor IDs that are always considered reachable (GC roots).

Implementations

impl TensorGarbageCollector

pub fn new() -> Self

Create a new, empty garbage collector.

pub fn register(&mut self, tensor: TensorRef)

Register a tensor with the collector.

If a tensor with the same tensor_id already exists it is replaced.

pub fn add_root(&mut self, tensor_id: u64)

Add tensor_id to the GC root set.

Roots are always considered reachable regardless of incoming edges. Duplicates are silently ignored.

pub fn remove_root(&mut self, tensor_id: u64)

Remove tensor_id from the GC root set.

Does nothing if the ID is not present.

pub fn pin(&mut self, tensor_id: u64)

Mark a registered tensor as pinned so it is never collected.

Does nothing if tensor_id is not registered.

pub fn add_ref(&mut self, tensor_id: u64)

Increment the external reference count for tensor_id.

Does nothing if tensor_id is not registered.

pub fn remove_ref(&mut self, tensor_id: u64)

Decrement the external reference count for tensor_id (saturating at 0).

Does nothing if tensor_id is not registered.

pub fn reachable_set(&self) -> Vec<u64>

Compute the set of tensor IDs reachable from roots and pinned tensors without mutating collector state.

Reachability is determined by BFS expansion through TensorRef::dependencies edges.

pub fn collect(&mut self) -> GcStats

Run a complete mark-and-sweep garbage collection cycle.

The collection proceeds through three GcPhases:

• GcPhase::MarkRoots — seed the reachable set from roots and pinned tensors.
• GcPhase::Trace — BFS-expand through dependency edges.
• GcPhase::Sweep — remove unreachable tensors with ref_count == 0.

Returns GcStats describing the result.

Trait Implementations

impl Default for TensorGarbageCollector

fn default() -> Self

Returns the “default value” for a type.