Module atomics 

Atomic operation reference implementations. Atomic operation semantics enforced by the parity engine.

GPU atomic instructions vary in memory ordering and return-value behavior across backends. This module exists to define one sequentially consistent, return-old-value semantics that every backend must match byte-for-byte.

Functions

apply

Apply one sequentially consistent atomic operation.

atomic_add

Return the old value and the value after atomic add.

atomic_and

Return the old value and the value after atomic bitwise AND.

atomic_compare_exchange

Return the old value and the value after atomic compare-exchange.

atomic_exchange

Return the old value and the replacement value for atomic exchange.

atomic_lru_update

LRU-update semantics: replace the slot with value only when value is strictly greater than old (the “more recent timestamp” wins). Identical tie-breaker behavior to atomic_max, kept as a distinct op so backends can lower it to a dedicated LRU-tracking instruction on hardware that has one. CPU reference is the correctness oracle.

atomic_max

Return the old value and the value after atomic unsigned maximum.

atomic_min

Return the old value and the value after atomic unsigned minimum.

atomic_or

Return the old value and the value after atomic bitwise OR.

atomic_xor

Return the old value and the value after atomic bitwise XOR.