Env-gated (COLI_METAL_RESSET=1) persistent MTLResidencySet attached to g_queue
(macOS 15+, @available-guarded with a one-line stderr fallback). Adds
resset_add/resset_remove/resset_flush helpers, wires them into the existing
coli_metal_register/coli_metal_unregister/coli_metal_shutdown bodies -- no new
functions in backend_metal.h, no glm.c changes, every existing call site keeps
its current signature and behavior.
register() defers the commit (resset_add just marks dirty, under the same
g_slab_mtx that already serializes parallel OMP loader threads) so a loader
burst doesn't pay a commit per slab; unregister() commits synchronously and
immediately, because the caller frees the underlying host memory right after
it returns and a deferred removal would leave the set referencing freed
memory. Nothing yet reads g_resset_enabled to change dispatch behavior --
this commit is bookkeeping only, gate on or off, so it does not change what
any command buffer does (verified by inspection: no useResource:/useHeap:
call site is touched here).
Gate off (default) is byte-for-byte the stock path: g_resset_enabled starts
false and nothing sets it outside the COLI_METAL_RESSET branch in
coli_metal_init, so every new helper is a no-op.
See SUMMARY.md (next commit) for the full design and UNCERTAINTIES.
monotophic
0049ea15ae