The persistent vector was a flat Scheme vector with copy-on-write: every conj
copied the whole backing array, so building an n-element vector was O(n^2). On the
collections bench that's vec-sum building 7500 elements with 227MB of copies, 90%
of the bench's allocation.
Replace it with Clojure's PersistentVector — a 32-way trie plus a trailing tail
chunk. conj appends to the tail and, when it fills, path-copies it into the trie,
so conj is O(1) amortized and a linear build is O(n). nth/assoc/pop are
O(log32 n). make-pvec (build a trie from a flat vector) and pvec-v (materialize
back) stay as compatibility shims, so the ~14 callers that read the backing array
— all one-shot conversions in =, hash, seq, meta-copy, transients, the reader —
are untouched; only this file's internals change.
vec-sum 70ms/227MB -> 1ms/3MB; collections 10.4x -> 4.0x vs JVM, under the 5x
target. 5 new corpus rows plus boundary stress (level transitions at 32 and 1024,
pop-collapse, assoc at every index) cover the trie.
Co-authored-by: Yogthos <yogthos@gmail.com>
* Make the benchmark harness build optimized binaries on Chez
bench/run.sh was Janet-era: it invoked a 'jolt' binary and set
JOLT_DIRECT_LINK/JOLT_WHOLE_PROGRAM, none of which exist on Chez, where
'joltc run -m' runs fully unoptimized (direct-link and inline default off). So
the suite was measuring jolt's unoptimized path.
run.sh now compiles each benchmark to an optimized AOT binary (joltc build
--direct-link --opt) and times it against JVM Clojure on the same portable
source, auto-detecting the Chez kernel dev files like build-smoke.sh. Adds
bench/deps.edn so joltc resolves the namespaces, NO_JVM to skip the reference.
mandelbrot.clj dropped its jolt.png require so the JVM reference can run it; the
picture demo moved to mandelbrot_png.clj (jolt-only). README scorecard refreshed
with current Chez numbers and the two-regime read (compute ~8-10x substrate floor;
dispatch/alloc ~120-330x architectural gaps the passes don't touch). Stale
'jolt -m' header lines point at bench/run.sh.
* Emit direct self-calls for named-fn self-recursion
A self-recursive call to a named fn compiled to (jolt-invoke fib ...) instead of
a direct (fib ...): emit-invoke handled a :local callee only when it was NOT a
known proc, so a :local that IS in *known-procs* (the letrec-bound self-name) fell
through to the :else jolt-invoke branch. Now a :local known proc emits a direct
Scheme call — no jolt-invoke, no per-call arg-list consing; case-lambda handles
arity.
fib 30: 63.3ms -> 4.7ms (faster than JVM Clojure's 7.1ms; was 9x slower). The win
is on every self-recursive non-loop fn, including the compiler's own. No semantic
change — selfhost holds, make test green, shakesmoke/buildsmoke byte-identical.
Re-mint (backend is seed). Corpus rows pin self-recursion across fixed/multi/
variadic arities.
* Intern no-ns keywords without per-call allocation
(keyword #f name) built a fresh combined-key string (string-append) on every
call just to do the intern-table lookup — ~80 bytes of garbage per (:kw x), map
literal, keyword arg, etc. A no-ns keyword now interns in a table keyed by the
name string directly, so a lookup of an already-interned keyword is one
hashtable-ref with no allocation. The ns table keeps the combined key; both share
the keyword-t khash (equal-hash of the combined key) so hash values are unchanged.
Small time win on its own (the field-read dispatch dominates hot record code —
see jolt-unx4) but removes per-call keyword allocation everywhere. Runtime .ss,
no re-mint; identity/=/hash unchanged, make test green.
* Fast record field reads: single eq? scan, skip the get-arm walk
(:field rec) / (get rec :field) lowers to (jolt-get rec kw), which walked the
get-arm list to reach the jrec arm, then did jrec-has? + jrec-lookup — TWO linear
scans, each comparing keys through the generic jolt=2 equality dispatcher. Field
keys are interned keywords, so:
- jrec-key=? compares a keyword query by eq? (jolt=2 only for non-keyword keys),
- jrec-ref does ONE scan (vs has?+lookup) and runs a deftype's ILookup valAt only
when the field is genuinely absent (present-nil still returns nil, not default),
- jolt-get-dispatch checks jrec? first, skipping the get-arm walk for the hottest
get target. jrec-lookup/jrec-has? (used by =, contains?, etc.) get the fast
compare too.
binary-trees 135x->18.9x, dispatch 121x->26.4x, mono-dispatch 327x->108x vs JVM.
Runtime .ss (collections.ss + records.ss), no re-mint; make test + shakesmoke +
buildsmoke green, record get/assoc/keys/=/count semantics unchanged.
---------
Co-authored-by: Yogthos <yogthos@gmail.com>
Running clojure.core.match (a macro-heavy library that builds its compiler out
of deftypes implementing clojure.lang interfaces) shook out a cluster of general
gaps. Its own suite goes from not-loading to 111/115 assertions.
- deftype/defrecord implementing a clojure.lang collection interface now drives
the core fns: Indexed -> nth, Counted -> count, Associative -> assoc, ILookup
-> get/valAt (non-field keys only, so a method's own field bindings don't
recurse), ISeq -> seq/first/rest, IPersistentCollection -> conj, IFn -> the
value is callable. A jrec is still a map of fields by default; the interface
method wins when declared.
- Multi-arity inline methods are grouped into one fn (a type with (nth [_ i]) and
(nth [_ i x]) kept only the last before). Built as data, not a nested
syntax-quote, so a `(= ~ocr ~l) method body keeps its unquotes.
- instance?/satisfies? recognize a protocol a type implements, including a MARKER
protocol with no methods (core.match's IPseudoPattern) — deftype/defrecord now
record protocol satisfaction even with zero methods. Added ILookup/Indexed/
Counted to the instance? taxonomy for the built-in collections.
- Syntax-quote: a fully-qualified class name (clojure.lang.ILookup) stays bare
instead of being namespace-qualified; (unquote x) is detected in a lazy seq
(a macro that builds its template with map, e.g. deftype's rewrite-set).
- clojure.set union/intersection/difference are variadic (& sets) + union 0-arity.
- java map view methods: keySet/values/entrySet/size/isEmpty.
- deprecated java.util.Date getters (getYear/getMonth/...) + the multi-arg
(Date. year-1900 month0 date hrs min) constructor.
Seed change (deftype/defrecord macros + clojure.set) -> re-minted; the rest are
runtime. 11 JVM-certified corpus rows; make test + shakesmoke green.
conj/assoc/dissoc/disj/pop/into and empty now thread the receiver's
metadata onto the result, matching Clojure (each op constructs a new
collection with meta() carried forward; coll.empty() is
EMPTY.withMeta(meta())). The metadata side-table is now weak so meta on
intermediate collections is reclaimed with them, and empty-list-t carries
an (unused) field so a metadata-bearing () is a distinct identity from the
shared singleton instead of leaking meta onto every ().
Unblocks metadata-driven walks (aero/integrant): (into (empty form) ...)
now preserves a vector/map/set's metadata, so a postwalk whose outer fn
reads (meta x) sees it.
jolt-get (4 sites: host-table/natives-misc/inst-time/records) and jolt=2 (6 sites:
records/vars/inst-time/natives-misc/bigdec/host-table) move off the set!-rebind
chains to register-get-arm! / register-eq-arm!. get's case-lambda becomes a stable
2/3-arg entry over a 3-arg dispatch; the equality arm pred is (a b) since either arg
may carry the type, and the host-table sorted arm normalizes-then-re-dispatches.
Behaviour-preserving (runtime .ss): var/inst/bigdec/record/uuid equality, record!=map,
sorted-map=plain-map, and all the get cases verified; make test green, 0 new corpus
divergences. Four of six dispatchers done; the printer (pr-str/pr-readable) remains.
- take-last / drop-last return seqs, not vectors: take-last wraps in seq; drop-last
is the JVM (map (fn [x _] x) coll (drop n coll)) form (lazy, () when empty).
- cycle is lazy ((lazy-seq (concat coll (cycle coll)))) so it no longer counts its
argument and terminates on a lazy/infinite input.
- fold's foldable-call catch uses :default, matching the rest of jolt-core and
also catching a raw host condition from a folding primitive.
- alts! rejects non-channel ports with a clear error (put specs / :default are
unsupported) instead of crashing inside ac-poll!.
- Misc: drop the unreachable second getCause clause; jolt-nth on a string raises
'nth "index out of bounds" like the vector branch; name the inline fixpoint cap;
bld-sh-capture rejoins lines with newlines; clarify a couple of comments.
Rename src/jolt -> stdlib (the runtime-loaded layer; jolt-core stays the
seed-baked layer) and update the loader / emit-image / doc paths. Drop dead
code: the spike/ experiments, the duplicate clojuredocs-export.edn (json moves
to tools/), the Janet-era jolt.http binding, and the orphaned
persistent_vector.clj whose ns/path didn't even match.
Strip porting residue from comments and docstrings across host/chez, jolt-core,
stdlib, tests, and docs: internal issue ids, "Phase N" markers, and the "vs
Janet" historical exposition, leaving present-tense descriptions and the real
JVM-Clojure semantic contrasts. Same pass over the corpus suite labels. The seed
is unchanged (docstrings/comments aren't emitted), so the self-host fixpoint and
corpus are untouched.
Port tools/spec_coverage.py off the dead janet probe to bin/joltc and regenerate
coverage.md; drop the dead :host/janet rule from certify.clj and regenerate the
conformance profile. Add docs/host-interop.md (the JVM shims and how to register
your own host class from a library) and a writing-style note in CLAUDE.md.
Stabilize the four racy concurrency corpus cases (future-cancel and agent
send/send-off): give the future a sleeping body and the agent a slow action, so
cancel reliably catches an in-flight future and deref reliably reads the
pre-update snapshot. They certify deterministically now, so drop their :flaky
allowlist entries and the orphaned legend.
Shaking the ring-app example's real library stack out against jolt surfaced a
batch of divergences from JVM Clojure, the biggest being evaluation order.
backend_scheme: call and recur arguments were emitted as bare Scheme operands,
so Chez's unspecified (right-to-left) order won out. Clojure evaluates left to
right, which selmer's reader loop relies on: (recur (add-node ... rdr) (read-char
rdr)) consumed a char early and dropped the first chars of every {{tag}}. Bind
operands to fresh temps in a let* (only when two or more can have side effects,
so hot calls over locals/consts stay un-wrapped). emit-ordered already did this
for collection literals; generalize it.
host-contract: syntax-quote now resolves the alias part of a qualified symbol
(impl/foo -> clojure.tools.logging.impl/foo) instead of leaving it bare, which
limped along via short-name matching until two loaded namespaces (reitit.impl,
clojure.tools.logging.impl) shared the short name and it broke.
collections: key-hash masks with bitwise-and, not fxand — jolt-hash is set!-
decorated per type (records return their own hash) and Chez's equal-hash can be a
bignum, so a key's hash isn't always a fixnum.
seq: even?/odd? handle bignums (JVM accepts any integer; the fxand crashed).
records: Keyword/Symbol .sym/.getName/.toString (honeysql's :clj branch reads
(.sym k)); Throwable .getMessage/.toString over a Chez condition.
host-static: __register-class-ctor!/__register-class-statics! so a host shim
(reitit.trie-jolt) can mirror a Java class.
natives-str: String.intern returns the string.
sqlite: jdbc.core fetch/fetch-one kebab-case column keys (the jolt-lang/db
convention; created_at -> :created-at).
io: a relative io/file path resolves against JOLT_PWD (the user's cwd), not the
repo root the launcher cd'd to — matches JVM cwd semantics, so config.edn loads.
cli: render an uncaught jolt throw (ex-info message + ex-data, or a condition)
instead of Chez's opaque "non-condition value" dump.
Rephrase comments that pointed at deleted Janet files (emit.janet, the seed
sources, 'the Janet back end punts ...') to present-tense descriptions of the
Chez behavior. Comment/docstring-only; the self-host fixpoint is unchanged
(comments don't affect the compiled seed).
Delete five files that were Janet-host shims with no Chez path: clojure.java.io
(provided natively by host/chez/io.ss), and jolt.{nrepl,png,interop,shell}
(the janet.* bridge, os/shell, janet.net — none exist on Chez).
jolt-cf1q.6
jolt was all-flonum (one :number type, inherited from Janet whose only number
type is a double). The Chez runtime has a full numeric tower, so the zero-Janet
path now carries it = JVM Clojure semantics:
(/ 1 2) => 1/2 (exact Ratio, was 0.5)
(integer? 3) => true (integer? 3.0) => false (float? 3.0) => true
(ratio? (/ 1 2)) => true (= 3 3.0) => false (== 3 3.0) => true
(+ 1 2) => 3 (exact) (/ 1.0 2) => 0.5 (double)
jolt= was already exactness-aware (values.ss) and == is value-equality, so
=/== match the JVM split. The reader preserves exactness (integer literals exact,
a/b ratios exact rationals, decimals/exponents flonums); backend_scheme emit-const
renders exact ints/ratios and flonums faithfully; the value-position arithmetic,
count, int, compare, bit ops, parseLong, string .length/.indexOf, range,
timestamps, and array bytes return exact integers (= JVM int/long) instead of
coercing to flonum. double/parseDouble/clojure.math floor|ceil|signum stay double.
Only the zero-Janet path carries the tower (the Janet reader loses exactness into
a double before emit). The prelude/all-flonum path is unaffected for compiled code;
the runtime reader is shared, so a couple of all-flonum reader assertions become
value (==) assertions. ~16 numeric corpus cases now give the JVM tower value vs the
Janet-era :expected and are allowlisted as tower divergences (Chez == reference
JVM) pending the corpus flip to JVM (jolt-ecz0). No BigDecimal type (1M).
Re-minted. zero-janet 2682 (floor 2698->2682, the reclassified tower cases), 0 new
divergences; fixpoint 10/10, bootstrap 6/6, spine 35/35, cli 49/49; Janet gate 155
files 0 failed.
list? was nil on Chez because one cseq record backs both lists and lazy/
realized seqs. Add a list? marker field (cseq v2) set only on the HEAD cell
of a list -- (list ...), quoted list literals, cons, reverse, conj onto a
list. rest/next/seq/map therefore yield unmarked seq cells, so they are
seqs and not list?, matching the seed (where rest-of-a-list is a non-list
seq). Empty () is treated as a list.
vector?: drop the map-entry exclusion. Clojure's MapEntry implements
IPersistentVector and the seed agrees -- (vector? (first {:a 1})) is true.
Only dot-forms' coll dispatch read jolt-vector?, where a 2-vector entry is
correct.
clojure.walk + clojure.template join the prelude stdlib tier. The driver
now evals each stdlib ns's requires -- and the ns form's (:require ...)
clause -- so an aliased ref (template's walk/postwalk-replace) resolves at
emit time instead of lowering to an Unknown class host-static. ns forms are
evaled for that side effect but not emitted, so the runtime *ns* doesn't
leak to the last stdlib ns.
Parity 2163 -> 2176, 0 new divergences. New test/chez/_walk.janet 39/39.
set/hash-map/hash-set/array-map/rand resolved to jolt-nil on the prelude
(the apply-jolt-nil crash bucket) — the pmap/pset ctors already existed in
collections.ss, just bind the public clojure.core names to them.
Map entries are now a distinct type: a pvec carries an ent flag (default #f),
so an entry equals its [k v] vector and walks like one (nth/count/seq/=/hash/
print read only v) but is not vector? and is map-entry? — matching Clojure's
MapEntry. seqing a map produces flagged entries; vector? excludes them. This
unblocks key/val (overlay fns gated on map-entry?) and the every? map-entry?
cases.
Prelude parity 1534 -> 1593, 0 new divergences. jolt-agw6.
jolt-y1zq tail:
- 0-arg (conj) -> [] and 0-arg (conj!) -> a fresh transient vector
- nth sees through a transient (like get/count/contains?)
- irregex \p{...}/\P{...} property classes translate to the seed's ASCII char
classes (regex.ss): \p{L} -> [a-zA-Z] + non-ASCII codepoints (the seed counts
UTF-8 high bytes as letters), \p{N} -> [0-9], \p{Ps} -> [([{], etc. The
translator tracks [...] nesting so a \p{} inside a class emits its content, not
a nested class.
Two pre-existing bugs found and filed (tracked, not replicated):
- jolt-x0os: the Chez emitter mangles non-ASCII string literals into invalid Chez
hex escapes (so p{L} utf-8 crashes on the input string, not the regex).
- jolt-ea9k: the seed's transient assoc! accepts odd args and assigns nil to the
trailing key (non-Clojure; plain assoc throws). The Chez host throws
(Clojure-correct); the 4 spec rows encoding the leniency are flagged in
transients-spec.janet pending the seed fix.
Parity 1493 -> 1506/2497, 0 new divergences. emit-test 291/291.
Brings up the seq layer on the Chez runtime. host/chez/seq.ss adds one
lazy-capable node (cseq) that models Clojure's list, cons, and lazy seq -
all print as (...), all sequential-= to each other and to vectors. seq
coerces any seqable (vector/map/set/string/list/seq/nil) to a cseq or nil;
the empty seq is a distinct value printing () (rest of a 1-elem coll is ()
not nil, seq of empty is nil). Leaf ops: first/rest/next/seq/cons/list,
reverse/last, map/filter/remove/reduce/into, range/take/drop/concat/apply,
keys/vals, plus nth/peek/pop extended over seqs. map/filter/reduce apply
their fn arg through jolt-invoke, so a procedure, keyword, or collection all
work as the fn.
Dynamic IFn dispatch: a keyword/vector/coll held in a local (let binding or
fn param) and called as a fn now routes through the jolt-invoke fallback
(procedure? -> apply; keyword/coll -> lookup). The emitter only routes a
:local callee that isn't a known procedure - a named fn's self-recursion
name stays a direct call, so the fib hot path is untouched. Closes the 3
ex-known IFn divergences.
emit.janet: seq/pred ops added to native-ops with arity gates; value-position
clojure.core refs resolve to the RT procedure (native-ops names one for each),
with +/-/*// routed to flonum-coercing wrappers so higher-order arithmetic
((reduce + [])) keeps the all-double model. values.ss: cross-type sequential
=/hash so a vector and a list of the same elements are jolt= and hash alike.
rt.ss: printer learns seqs; top-level nil prints as the empty string (jolt -e
str-style). Fixed latent bug: (conj nil ...) now builds a list, not a vector.
Gates: emit-test 69/69 (fib/mandelbrot/collections/seq/IFn parity vs the jolt
oracle, fib(30) ~24ms unchanged). Subset probe 433/436 -> 595/595 compiled,
0 divergences (was 3 known), 2060/2655 out of subset. Full run-tests green
(125 files, conformance + suites included).
Broaden the Scheme back end past the numeric/functional subset to vectors,
maps, and sets. host/chez/collections.ss adds a copy-on-write persistent
vector and a bitmap HAMT (the structure 0c measured self-hostable) backing
both maps and sets, keyed by jolt-hash and compared by jolt=. emit.janet
emits :vector/:map/:set literals to the rt constructors and lowers the leaf
ops (conj/get/nth/count/assoc/dissoc/contains?/empty?/peek/pop) via the
native-ops path, with a per-op arity gate.
Also: keyword/map literals in fn position lower to jolt-get ((:k m), ({:k v} k));
arity-1 comparisons emit the vacuous jolt truth (Scheme < rejects a non-number
even at arity 1); count returns a flonum and vector indices coerce from flonum,
both consequences of the all-double number model; values.ss = / hash and the
rt printer learn collections (maps/sets render in HAMT order, so the probe
compares unordered values via =, not printed form).
Subset parity 182 -> 433/436 compiled cases (2219/2655 out of subset), 0 new
divergences. The 3 known divergences are dynamic IFn dispatch (a keyword/vector
held in a local, called as a fn) — deferred to the IFn/protocol increment and
allowlisted in the probe. emit-test 31/31, full run-tests green (125 files).
