Elide the redundant jolt-truthy? wrapper on an :if test that provably
yields a Scheme boolean (a native comparison/not, or a boolean const).
Sound because jolt-truthy? of #t/#f is identity. The hot fib/mandelbrot
tests are all comparisons, so this is a direct ceiling lever: fib(30)
end-to-end 24.0 -> 14.4 ms.
Add bench-pipeline.janet (JOLT_CHEZ_BENCH=1, opt-in) timing fib(30) +
mandelbrot(200) through the real pipeline vs the spike ceiling.
Mandelbrot 200 runs at 87 ms, at/below the 98 ms generic-flonum ceiling
- the substrate ceiling is reached end-to-end. fib sits at 2x its
hand-flonum ceiling; the residual is jolt's all-double number model
(typed fl*/fx* emission is Phase 4). Compile-only is total for the
compute subset (every form emits; Chez has no interpreter fallback).
Full parity unchanged at 1534/2494, 0 new divergences.
0c: persistent HAMT on Chez is ~41x faster than Janet's HAMT on the collections
map-churn (258.6 -> 6.3 ms), ~15x off mutable-native (inherent persistence cost).
Decision: self-host the persistent collections in Clojure; substrate is not the
bottleneck. See docs/chez-phase0-results.md.
0a hardening: NUL-separated keyword intern key (no ns/name collision), non-finite
-safe jolt-hash. 37/37.
Hand-translate the two compute benches into the Scheme a jolt->Chez backend
would emit, to localize the execution-substrate ceiling without porting the RT.
fib 30: 246.6 -> 5.2 ms (~47x, fixnum). mandelbrot 200: 166.3 -> 13.4 ms
(~12.4x) ONLY with flonum-specialized ops; generic float ops box every flonum
and stay ~1.7x. 13.4 ms matches jolt's JOLT_CGEN C result, so Chez's native
compiler reaches the C ceiling with no cc step, REPL intact.
Size: Chez base 2.9 MB (AOT) / 4.0 MB (dynamic) vs Janet 2.21. Memory: Chez
~32-49 MB fixed baseline vs Janet ~12 MB (the one regression). RT-bound axes
(collections/binary-trees, where Chez's generational GC should help) not yet
measured. See spike/chez/RESULTS.md.
