compile-fn now keys the .so on a hash of the generated C + the Janet ABI + the
platform, in a persistent cache dir (default jolt-cgen under TMPDIR, override
with JOLT_CGEN_CACHE_DIR; JOLT_CGEN_NO_CACHE=1 forces a rebuild). cc runs only on
the first build of a given fn; later runs with the same source reuse the cached
.so, so the per-startup compile cost is paid once.
mandelbrot 100 whole-process wall: cold ~0.71s -> warm ~0.21s (the ~0.5s cc
cost). These cache knobs don't shape output, so they stay out of
ctx-shaping-env-vars (same as the image-cache knobs). Test asserts the .so is
content-addressed and a second compile hits the cache without the source .c.
Co-authored-by: Yogthos <yogthos@gmail.com>
First slice of the native-codegen tier. A new standalone module, src/jolt/
cgen.janet, that translates a numeric-leaf fn (numeric in/out, body uses only
native-op arithmetic + loop/recur/if/let/do) to a Janet native C module: params
unboxed to C doubles at entry, loop/recur lowered to a while loop, reboxed at
return. compile-fn runs cc and loads the .so via the native builtin, returning a
cfunction; it returns nil for non-candidates or when the toolchain is absent.
count-point compiles and matches the bytecode fn across the mandelbrot grid
(test/integration/cgen-test.janet, which skips the behavioral leg where cc/janet.h
are missing). Nothing wires this into the default compile path yet — detecting
hot fns and installing the C version onto the var cell is the next step.
See docs/foundational-runtime-lever1-native-codegen.md for the ceiling
(native-C ~18-22x faster than bytecode, edges out JVM) and the leaf-first rule.
Co-authored-by: Yogthos <yogthos@gmail.com>
