Adds a NULL-by-default lookup/populate callback seam on xce_sched_core_t,
mirroring cache_clear_cb's proven shape, so the allocation dispatch
chokepoint can consult the unsatisfiable-resreq cache without a
normal-mode-only field access in shared code. Adapters live in
alloc_cache.c and are registered only during normal-mode startup;
simulation mode leaves both callbacks NULL and always computes fresh.
Adds the scheduler-sim-live-allocation spec (requirements/design/
research/tasks) as the planning artifact this and subsequent tasks
implement against.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RLSNJhNoULvVcUhXEFafQC
Clear the cache inside core_begin_session_internal() so a job cached as
unsatisfiable in one session is re-evaluated fresh in the next (Req 7.2).
An initial weak-symbol cast-based approach was rejected: it corrupted
xce_sched_sim_driver_t.alt_events_file, since core_begin_session_internal()
is shared between driver.c (real xce_scheduler_t) and sim_loop.c (a
structurally different, deliberately isolated sim driver struct with no
cache field at the same byte offset) -- the strong cache_clear() symbol
won unconditionally for both, invisible to ASAN and untested by any
test_sim_*.c file.
Fixed via a driver-registered callback: xce_sched_core_t gains a
cache_clear_cb hook (NULL by default, per xce_sched_core_init()'s
full-struct memset), set only in main.c's driver-mode branch --
mirroring the existing on_decision/xce_core_set_decision_cb() pattern.
--sim mode returns before that registration is ever reached, so its hook
stays NULL and core_begin_session_internal()'s guarded call is a no-op.
The real xce_scheduler_t-casting adapter lives in alloc_cache.c rather
than driver.c, since ~11 tests white-box-include driver.c without
linking alloc_cache.c.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XYdtrEWWZfKRRGED7raEYg
Adds alloc_cache.c: xce_cache_key_t, cache_key_ops (the corrected
three-way, 0-means-equal .cmp -- an inverted-boolean version was a
real bug found during design review), and cache_lookup/insert/clear
against a real kvtab_t (constructed matching xce_select.c's
sel_node_table_init() precedent). Cache values are a boxed reason-
category int, not a bare hit/miss sentinel, satisfying Req 7 AC5's
requirement that a hit reproduce the original pend-reason category.
unsatisfiable_cache lives on xce_scheduler_t per Req 7 AC1.
Task 2.2 (scheduler-allocation spec). Requirements 7.1, 7.3, 7.4, 7.5.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01XYdtrEWWZfKRRGED7raEYg
