Class ov::pass::FuseGDNLoop

class FuseGDNLoop : public ov::pass::MatcherPass

Fuses a loop-based gated delta net sub-graph into an internal GatedDeltaNet operation.

Expected Loop body semantics per step: 1) Decay recurrent state: h_decay = h * exp(g) 2) Compute projection and delta: delta = v - reduce_sum(h_decay * k, axis=-2) 3) Apply beta and update state: h_new = h_decay + k * unsqueeze(delta * beta, axis=-2) 4) Compute per-step output: o = reduce_sum(h_new * q, axis=-2, keep_dims=true) and scatter to time index

The matcher validates this body shape/operation pattern before replacing the Loop with GatedDeltaNet.