# src/starkernel/vm/

Kernel-side StarForth VM subsystem.

- `vm_core.c` — kernel port of the core interpreter loop.
- `vm_runtime.c` — kernel VM runtime support.
- `vm_bootstrap.c` — kernel VM bootstrap (distinct from
  `bootstrap/sk_vm_bootstrap.c`, which owns the higher-level subsystem
  wiring called from `kernel_main.c`).
- `arena.c` — capsule arena allocator (fixed-region allocation for capsule
  payload data).
- `parity.c` — birth/execution parity logging (VM ID + capsule hash +
  dictionary hash), enabling offline determinism verification.
- `alloc_kernel.c` — the kernel-side implementation of the VM's allocator
  interface actually referenced by `Makefile.starkernel`'s build (see
  `src/platform/README.md` for a note on a second, unwired copy).
- `q48_stubs.c` — deliberate no-op stubs for `q48_from_double()`/
  `q48_to_double()` in the freestanding kernel build, where floating point
  is unavailable; always returns zero, safe because shared VM code only
  uses these results for logging/diagnostic paths that are inactive in
  the kernel build.
- `vm_internal.h` — internal-only declarations shared across this
  directory's files.

Subdirectories:
- `bootstrap/sk_vm_bootstrap.c` — owns VM init + capsule loading wiring,
  called from `kernel_main.c`; `kernel_main.c` itself only owns hardware
  milestones.
- `host/shim.c` — host-service shim bridging the kernel VM to
  `src/starkernel/hal/host_services.c`.