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^long is a 64-bit long: fast-path-with-fallback ops + logical unsigned shift

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Completes the JVM long-compatibility gap so clojure.test.check (and the
property-based suites built on it, e.g. data.codec) run on jolt.

A ^long is 64-bit but a Chez fixnum is only 61-bit, so the backend's fast fx
comparison / quot / min / max / inc / dec ops raised on a full-width long (one
from the PRNG or wrapping arithmetic). They now go through the jolt-l* macros
(host/chez/seq.ss): the fx fast path when the operands ARE fixnums, the generic
op otherwise — so e.g. ((fn [^long a ^long b] (< a b)) Long/MAX 1) is false, not
an error. Arithmetic +/-/* keep the raw fx ops (under *unchecked-math* they're
already the wrapping unchecked-*).

Also fixes unsigned-bit-shift-right: it was an arithmetic (sign-propagating)
shift, now a logical shift over the 64-bit two's-complement window, so
(unsigned-bit-shift-right -1 1) is 2^63-1 like the JVM.

Result: test.check 1.1.3 loads and runs (generators, quick-check, shrinking);
data.codec's base64 property suite passes (12/12 defspecs; the 2 deftests check
clojure.lang.IFn$OLLOL, a JVM primitive-fn interface, N/A). Both added to
docs/libraries.md + the site.

re-mint (backend/seed). make test green (+3 corpus rows, 0 new divergences,
numeric gate updated to the jolt-l* ops), shakesmoke byte-identical.
This commit is contained in:
Yogthos 2026-06-27 16:04:19 -04:00
parent a028cab04f
commit 3340635714
7 changed files with 62 additions and 20 deletions
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3
test/chez/corpus.edn
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@ -3375,4 +3375,7 @@
{:suite "numbers / unchecked wraps to signed 64-bit" :label "unchecked-negate of MIN wraps to MIN" :expected "-9223372036854775808" :actual "(unchecked-negate -9223372036854775808)"}
{:suite "numbers / unchecked wraps to signed 64-bit" :label "unchecked-inc of MAX wraps to MIN" :expected "-9223372036854775808" :actual "(unchecked-inc 9223372036854775807)"}
{:suite "host-interop / Long bit statics" :label "Long/bitCount, numberOfLeadingZeros, reverse" :expected "[10 63 0 -2]" :actual "[(Long/bitCount 1023) (Long/numberOfLeadingZeros 1) (Long/bitCount 0) (Long/reverse 9223372036854775807)]"}
{:suite "numbers / unsigned-bit-shift-right is logical over 64 bits" :label "shift of a negative shifts in zeros" :expected "[9223372036854775807 4611686018427387902]" :actual "[(unsigned-bit-shift-right -1 1) (unsigned-bit-shift-right -8 2)]"}
{:suite "numbers / ^long is 64-bit" :label "^long comparison on a full-width long" :expected "false" :actual "((fn* ([^long a ^long b] (< a b))) 9223372036854775807 1)"}
{:suite "numbers / ^long is 64-bit" :label "^long quot on a full-width long" :expected "3074457345618258602" :actual "((fn* ([^long a] (quot a 3))) 9223372036854775807)"}
]