register_jit_hook is now installed in the persistent (epoch) serving-mode
branch of sx_server.ml, not just --http/cli/site. Smalltalk-on-SX conformance
under JIT is 847/847 — identical to the no-JIT baseline; Datalog 356/356.
run_tests --jit/no-jit are byte-identical before/after (no regression).
Five distinct root causes fixed (not one "miscompile"):
1. Serving mode never loaded lib/compiler.sx, so JIT used the native
Sx_compiler.compile stub (arity-0 bytecode, params as GLOBAL_GET →
"VM undefined: <param>"). Server-mode branch now loads compiler.sx
before registering the hook, matching http/cli/site.
2. compile-cond / compile-case-clauses / compile-guard-clauses only treated
keyword :else and true as the catch-all, not the bare symbol `else` that
the CEK's is-else-clause? accepts → GLOBAL_GET "else". (lib/compiler.sx)
3. OP_DIV produced a float for non-divisible Integer/Integer (1/2 → 0.5)
instead of the exact Rational the "/" primitive returns. Now delegates to
the primitive, matching CEK. (sx_vm.ml)
4. OP_EQ / _fast_eq lacked Rational/ListRef cases that the "=" primitive's
safe_eq has → (= 1/2 1/2) false under JIT. OP_EQ now delegates non-scalars
to the "=" primitive; _fast_eq gained rational + ListRef. (sx_vm.ml,
sx_runtime.ml)
5. Continuation-based control flow (Smalltalk ^expr non-local return, block
escape, exceptions via call/cc) can't run in the stack VM. New data-driven
exclusion set Sx_types.jit_excluded + `jit-exclude!` primitive, consulted in
jit_compile_lambda (covers both the CEK hook and vm_call's tiered path).
lib/smalltalk/eval.sx self-declares its continuation dispatch core
interpret-only; pure helpers still JIT. The SUnit suite-runner test helper
pharo-test-class miscompiles mid-loop and is excluded in tests/tokenize.sx.
Also adds SX_JIT_DENY / SX_JIT_ONLY env-var bisection filters to the serving
hook. Known residual documented in plans/jit-bytecode-correctness.md: the hook
re-runs a failed VM execution via CEK (correct result, possible duplicate side
effects); adopting run_tests' propagate-don't-rerun semantics is deferred to
avoid changing shared VM/CEK behavior under this loop.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
lib/guest/reflective/class-chain.sx — class inheritance walker with
adapter cfg for single-parent (Smalltalk) and multi-parent (CLOS)
hierarchies. Three primitives:
- refl-class-chain-find-with CFG CN PROBE
DFS through parents, returns first non-nil probe result.
Smalltalk method lookup uses this.
- refl-class-chain-depth-with CFG CN ANCESTOR
Min hop distance via any parent path, or nil if unreachable.
CLOS method specificity uses this.
- refl-class-chain-ancestors-with CFG CN
Flat DFS-ordered list of all reachable ancestor names.
Adapter cfg has two keys: :parents-of (CN → list of parent names,
possibly empty) and :class? (predicate; short-circuits walk on
non-existent class names mid-chain).
Migrations:
- lib/smalltalk/runtime.sx: st-method-lookup-walk now a 9-line
thin probe through the kit (was 20 lines of inline recursion);
st-class-cfg wraps the single-parent :superclass field into a
1-element list for the cfg.
- lib/common-lisp/clos.sx: clos-specificity is a one-line wrapper
around refl-class-chain-depth-with (was 28 lines); clos-class-cfg
reads the multi-parent :parents field.
Both consumers green:
- Smalltalk: 847/847 (unchanged)
- CL: 222/240 (unchanged baseline; 18 pre-existing failures, all
in stdlib functions like cl-set-memberp, unrelated to CLOS).
This is the second extracted reflective kit (env.sx was first).
The adapter-cfg pattern continues to bridge structurally divergent
consumers (Smalltalk single-inheritance vs CLOS multiple-inheritance
with method-precedence distance) via a uniform :parents-of callback.
lib/guest/reflective/env.sx — added refl-env-find-frame-with (returns
the scope where NAME is bound, or nil). Needed by consumers like
Smalltalk that mutate variables at the source frame rather than
shadowing at the current one. Also added refl-env-find-frame for
the canonical shape.
lib/smalltalk/eval.sx — new st-frame-cfg adapter for the kit.
st-lookup-local now delegates parent-walk to refl-env-find-frame-with
while preserving its Smalltalk-flavoured {:found :value :frame}
return shape (which is used to mutate at the binding's source
frame, not the current one).
lib/smalltalk/test.sh + compare.sh — load lib/guest/reflective/env.sx
before lib/smalltalk/eval.sx.
Three genuinely different wire shapes now share the parent-walk:
- Kernel: {:refl-tag :env :bindings :parent} mutable bindings
- Tcl: {:level :locals :parent} functional update
- Smalltalk: {:self :method-class :locals :parent mutable bindings,
:return-k :active-cell} rich metadata
All three consumers' full test suites unchanged: Smalltalk 847/847,
Kernel 322/322, Tcl 427/427. The cfg adapter pattern (modelled after
lib/guest/match.sx) cleanly handles all three.
