cli, cps interpreter, stack vm, closure-conversion, fixes, tests, LOL

2026-08-19 01:32:48 -06:00
parent 94b1a5fb45
commit c5f9bf1850
23 changed files with 587 additions and 99 deletions
@@ -2,8 +2,59 @@

 the closure-conversion phase makes closed-over variables explicit by addition of the primitive ~make-closure~, taking a code pointer (in the CPS language, bare lambda) and the environment.

+nice testable properties of closure-converted code:
+- code pointers only appear in function position
+- no function has free variables
+
+multiple ~env-ref~ calls could probably be replaced with a primitive that loads the entire environment at once, returning multiple variables.
+
 * scratchpad

+** example
+
+#+caption: scheme source
+#+begin_src scheme
+  (letrec ((curried-add (λ (n)
+                          (λ (m)
+                            (+ n m)))))
+    ((curried-add 3) 4))
+#+end_src
+
+#+caption: cps
+#+begin_src scheme
+  (letrec ((curried-add
+            (λ (n ktail0)
+              (letrec ((curried-add-in
+                        (λ (m ktail1)
+                          (prim (+ n m)
+                                (κ (x0) (continue ktail1 x0))))))
+                (continue ktail0 curried-add-in)))))
+    (letrec ((k0 (κ (adder) (adder 4 halt))))
+      (curried-add 3 k0)))
+#+end_src
+
+#+caption: closure-converted
+#+begin_src scheme
+  (letrec ((curried-add
+            (λ (n ktail0)
+              (letrec ((curried-add-in-code
+                        (λ (env m ktail1)
+                          (prim (env-ref 0 env)
+                                (κ (n)
+                                   (prim (+ n m)
+                                         (κ (x0) (continue ktail1 x0))))))))
+                (prim (make-closure curried-add-in-code n)
+                      (κ (curried-add-in)
+                         (continue ktail0 curried-add-in)))))))
+    (letrec ((k0 (κ (adder-closure)
+                    (prim (closure-code adder-closure)
+                          (κ (adder)
+                             (adder adder-closure 4 halt))))))
+      (curried-add 3 k0)))
+#+end_src
+
+** wasm
+
 #+begin_src scheme
 (letrec ((make-adder
        (lambda (n)