jolt/host/chez/seed
Yogthos e2598280fe DO NOT MERGE — reduce-acc SROA regresses (defeats vec-reduce)
Reduce-accumulator scalar replacement: lower (reduce (fn [acc x] body) (->Rec
inits) coll) with a non-escaping record accumulator to a loop carrying the acc
fields as scalar vars. Correct (run-reduce-sroa.ss 7/7, make test + shakesmoke
green) but a PERF REGRESSION: ray tracer hit-all 38.4s -> ~53s.

Root cause: jolt's reduce already iterates a vector with vec-reduce (seq.ss) — a
tight index loop over the backing store, zero per-element allocation. Lowering to
a (seq)/(first)/(next) loop allocates a seq node per element, trading hit-all's
CONDITIONAL ->HitAcc allocation for a per-element seq allocation. The targeted
accumulator allocation is also conditional (only on hit improvement), not the
dominant per-sphere cost. Kept on this branch for reference; not merged.
2026-06-26 11:28:34 -04:00
..
image.ss DO NOT MERGE — reduce-acc SROA regresses (defeats vec-reduce) 2026-06-26 11:28:34 -04:00
prelude.ss See through or/and in truthy-elision (#224) 2026-06-26 06:11:35 +00:00
README.md Docs: Chez-only, drop the Janet-era references and obsolete migration notes 2026-06-22 09:05:35 -04:00

Chez bootstrap seed

These two files are the bootstrap compiler for jolt — the seed that makes the build self-hosting:

  • prelude.ss — the clojure.core prelude (all tiers + clojure.string/walk/ template/edn/set/pprint) as Scheme def-var! forms.
  • image.ss — the compiler image (jolt.ir + jolt.analyzer + jolt.backend-scheme) as Scheme def-var! forms.

Both are generated, not hand-written. They are checked in because a fresh checkout must be able to build jolt-on-Chez using only Chez: host/chez/bootstrap.ss loads this seed, then rebuilds the prelude + image from the .clj/.ss sources via the on-Chez compiler (read → analyze → emit, all on Chez). The seed is a joint byte-fixpoint: rebuilding from an up-to-date seed reproduces it exactly. make selfhost (host/chez/selfcheck.sh) runs host/chez/bootstrap.ss and diffs the rebuilt artifacts against the checked-in seed.

Re-minting

When the seed sources change (the core tiers, the compiler namespaces, the host contract, the reader, emit-image.ss), the seed drifts and make selfhost fails. Re-mint it by running host/chez/bootstrap.ss and writing the freshly rebuilt prelude/image back to host/chez/seed/prelude.ss / host/chez/seed/image.ss, then commit the refreshed files.