Zero bootstrap patches: all 11 moved to spec or runtime

- make-raise-guard-frame: was never defined in spec — added it
- *last-error-kont*: set at error origination (host-error calls), not
  wrapped around every cek-run step. Zero overhead on normal path.
- JIT: jit-try-call runtime function called from spec. Platform
  registers hook via _jit_try_call_fn ref. No bootstrap patching.
- bootstrap.py compile_spec_to_ml() now returns transpiled output
  with zero post-processing.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

hosts/ocaml/bin/sx_server.ml

@@ -799,7 +799,7 @@ let _jit_compiling = ref false  (* re-entrancy guard *)
 let _jit_warned : (string, bool) Hashtbl.t = Hashtbl.create 16
 
 let register_jit_hook env =
-  Sx_ref.jit_call_hook := Some (fun f args ->
+  Sx_runtime._jit_try_call_fn := Some (fun f args ->
     match f with
     | Lambda l ->
       (match l.l_compiled with

hosts/ocaml/bootstrap.py

@@ -54,9 +54,6 @@ let _strict_ref = ref (Bool false)
 let _prim_param_types_ref = ref Nil
 let _last_error_kont_ref = ref Nil
 
-(* JIT call hook — platform-level optimization, registered by sx_server.ml *)
-let jit_call_hook : (value -> value list -> value option) option ref = ref None
-
 """
 
 
@@ -209,50 +206,6 @@ def compile_spec_to_ml(spec_dir: str | None = None) -> str:
     # the transpiler directly — it emits !_ref for reads, _ref := for writes.
     import re
 
-    # Inject make_raise_guard_frame if missing (transpiler merge bug drops it)
-    if "and make_raise_guard_frame" not in output:
-        RAISE_GUARD_FRAME = """
-(* make-raise-guard-frame — injected by bootstrap.py *)
-and make_raise_guard_frame env saved_kont =
-  (CekFrame { cf_type = "raise-guard"; cf_env = env; cf_name = Nil; cf_body = Nil; cf_remaining = saved_kont; cf_f = Nil; cf_args = Nil; cf_results = Nil; cf_extra = Nil; cf_extra2 = Nil })
-"""
-        output = output.replace(
-            "(* make-signal-return-frame *)\nand make_signal_return_frame",
-            RAISE_GUARD_FRAME + "\n(* make-signal-return-frame *)\nand make_signal_return_frame",
-        )
-
-    # === Platform-level patches (not spec concerns) ===
-
-    # Instrument recursive cek_run to capture kont on error (for comp-trace).
-    cek_run_old = (
-        'and cek_run state =\n'
-        '  (if sx_truthy ((cek_terminal_p (state))) then (cek_value (state)) else (cek_run ((cek_step (state)))))'
-    )
-    cek_run_new = (
-        'and cek_run state =\n'
-        '  (if sx_truthy ((cek_terminal_p (state))) then (cek_value (state)) else\n'
-        '   try cek_run ((cek_step (state)))\n'
-        '   with Eval_error msg ->\n'
-        '     (if !_last_error_kont_ref = Nil then _last_error_kont_ref := cek_kont state);\n'
-        '     raise (Eval_error msg))'
-    )
-    if cek_run_old in output:
-        output = output.replace(cek_run_old, cek_run_new, 1)
-
-    # Inject JIT dispatch into continue_with_call's lambda branch.
-    # Replace final make_cek_state in the lambda branch with JIT check.
-    jit_old = "(make_cek_state ((lambda_body (f))) (local) (kont))))))"
-    jit_new = (
-        "(match !jit_call_hook, f with "
-        "| Some hook, Lambda l when l.l_name <> None -> "
-        "let args_list = match args with List a | ListRef { contents = a } -> a | _ -> [] in "
-        "(match hook f args_list with "
-        "Some result -> make_cek_value result local kont "
-        "| None -> make_cek_state (lambda_body f) local kont) "
-        "| _ -> make_cek_state ((lambda_body (f))) (local) (kont))))))"
-    )
-    output = output.replace(jit_old, jit_new, 1)
-
     return output
 
 

hosts/ocaml/lib/sx_runtime.ml

@@ -474,3 +474,16 @@ let debug_log _ _ = Nil
 (* mutable_list — mutable list for bytecode compiler pool entries *)
 let mutable_list () = ListRef (ref [])
 
+(* JIT try-call — ref set by sx_server.ml after compiler loads.
+   Returns Nil (no JIT) or the result value. Spec calls this. *)
+let _jit_try_call_fn : (value -> value list -> value option) option ref = ref None
+let jit_try_call f args =
+  match !_jit_try_call_fn with
+  | None -> Nil
+  | Some hook ->
+    match f with
+    | Lambda l when l.l_name <> None ->
+      let arg_list = match args with List a | ListRef { contents = a } -> a | _ -> [] in
+      (match hook f arg_list with Some result -> result | None -> Nil)
+    | _ -> Nil
+

hosts/ocaml/transpiler.sx

@@ -252,7 +252,8 @@
     "component-set-file!"
     "parse-comp-params"
     "parse-macro-params"
-    "parse-keyword-args"))
+    "parse-keyword-args"
+    "jit-try-call"))
 
 (define
   ml-is-known-name?

spec/evaluator.sx

@@ -127,6 +127,8 @@
 
 (define make-raise-eval-frame (fn (env continuable?) {:scheme continuable? :env env :type "raise-eval"}))
 
+(define make-raise-guard-frame (fn (env saved-kont) {:env env :type "raise-guard" :remaining saved-kont}))
+
 (define
   find-matching-handler
   (fn
@@ -2640,8 +2642,10 @@
                   (handler-fn (kont-find-handler rest-k condition)))
                 (if
                   (nil? handler-fn)
-                  (host-error
+                  (do
-                    (str "Unhandled exception: " (inspect condition)))
+                    (set! *last-error-kont* rest-k)
+                    (host-error
+                      (str "Unhandled exception: " (inspect condition))))
                   (continue-with-call
                     handler-fn
                     (list condition)
@@ -2654,8 +2658,10 @@
                         rest-k)
                       (kont-push (make-raise-guard-frame fenv rest-k) rest-k))))))
             ("raise-guard"
-              (host-error
+              (do
-                "exception handler returned from non-continuable raise"))
+                (set! *last-error-kont* rest-k)
+                (host-error
+                  "exception handler returned from non-continuable raise")))
             ("multi-map"
               (let
                 ((f (get frame "f"))
@@ -2685,7 +2691,10 @@
                   (get frame "env")
                   (list k)
                   rest-k)))
-            (_ (error (str "Unknown frame type: " ft)))))))))
+            (_
+              (do
+                (set! *last-error-kont* rest-k)
+                (error (str "Unknown frame type: " ft))))))))))
 
 (define
   continue-with-call
@@ -2733,7 +2742,12 @@
           (for-each
             (fn (p) (env-bind! local p nil))
             (slice params (len args))))
-        (make-cek-state (lambda-body f) local kont))
+        (let
+          ((jit-result (jit-try-call f args)))
+          (if
+            (nil? jit-result)
+            (make-cek-state (lambda-body f) local kont)
+            (make-cek-value jit-result local kont))))
       (or (component? f) (island? f))
       (let
         ((parsed (parse-keyword-args raw-args env))