0-5-2-understand-hb-program-order

name	0.5.2-understand-hb_program_order
description	[0.5.2] The order of operations as they appear in source code within a single thread; a fundamental component of happe

understand-hb_program_order

CALL NUMBER: deep_happens_before_relat.hb_program_order DEFINITION: The order of operations as they appear in source code within a single thread; a fundamental component of happens-before that preserves intra-thread ordering.

Invoke this skill to understand hb_program_order down to its primitives. The RELATIVE ROOT below is the least-fixed-point closure of everything it bundles from — the full import cone, grouped by the lib each prim comes from. Projected from a prover-typed KB (MAP/SWI-Prolog consistency gate): every reference below resolves.

THE RELATIVE ROOT (the import cone, by lib)

from ?

• hb_synchronizes_with (d1): A synchronization operation or primitive that establishes an inter-thread happens-before relationship, ensuring that all memory effects preceding the synchronization point in one thread become visible to all operations following the corresponding synchronization point in another thread; the fundamental mechanism by which threads coordinate access to shared state, encompassing operations such as th

from deep_happens_before_relat

• hb_transitive_closure (d1): The transitive property of happens-before: if A happens-before B and B happens-before C, then A happens-before C.
• hb_acquire_semantics (d2): A memory ordering guarantee where all subsequent memory operations become visible only after the acquire operation; paired with release to establish synchronization.
• hb_release_semantics (d2): A memory ordering guarantee where all prior memory operations become visible before the release operation; paired with acquire to establish synchronization.
• hb_lock_acquire (d3): Acquiring a synchronization lock, which carries acquire semantics for all operations following the acquisition.
• hb_lock_release (d3): Releasing a synchronization lock, which carries release semantics for all operations preceding the release.

CONSUMERS (what needs this)

hb_modification_order, hb_thread_join, hb_thread_start

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Projected from the concurrency synchronization primitives and memory models KB (407 concepts / 477 relations) — consistency-typed by MAP; the facet list after the colon IS the cross-lib dependency web.

(leaf — this is an actual skill.)