WIP runtime re-write

asm/runtime.scm

@@ -1,33 +1,28 @@
 ;; Note that this is scheme syntax wrapping asm for a stack machine
+(variable eom 1024)
+;; These need to be initialized with the runtime
 (variable scan 0)
 (variable free 0)
-(variable eom 1024)
-;; These need to be initialized later
 (variable root 0)
-(variable the-cars 0) 
+(variable old 0) 
-(variable the-cdrs 0)
+(variable new 0)
-(variable new-cars 0)
-(variable new-cdrs 0)
-
 
 (push main)
 (jmp)
 
-alloc
+alloc ;; ( -- p)
 ;; Test if free will go beyond eom
-(push free)
+(ref free)
-(@)
 (dup) ; ( -- free free)
 (push 8)
 (+)
 (dup) ; ( -- free free+8 free+8)
-(push eom)
+(ref eom)
-(@)
 (<) ; ( -- free free+8 (free+8 < eom))
-(branch alloc-do-gc)
+(push alloc-do-gc)
+(if)
 ;; write free+8 to free
-(push free)
+(set! free)
-(!)
 ;; return the old free, it is memory the program can use
 (return)
 alloc-do-gc
@@ -41,36 +36,21 @@ alloc-do-gc
 (push alloc)
 (jmp)
 
-gc-start
+gc-start ;; ( -- )
-; Move scan & free back to 0
+; Move scan & free to start of new memory
-(push 0)
+(ref new)
-(push free)
+(dup)
-(!)
+(set! free)
-(push 0)
+(set! scan)
-(push scan)
+(ref root)
-(!)
+(push relocate-object)
-; Push the first cons to relocate (root)
+(call)
-(push root)
-(@)
-; Call the relocation routine
 (push gc-loop)
 (call)
-; Swap new and old cars and cdrs
-(push new-cars)
-(@)
-(push the-cars)
-(@)
-(push new-cars)
-(!)
-(push the-cars)
-(!)
-(push new-cdrs)
-(@)
-(push the-cdrs)
-(@)
-(push new-cdrs)
-(!)
-(push the-cdrs)
-(!)
-; return to allocation
 (return)
+
+relocate-object ;; (o -- )
+;; TODO
+
+main
+;; TODO

scmvm/assembler.scm

@@ -7,8 +7,14 @@
                 #:select (write-u8 write-bytevector))
   #:export (assemble))
 
+(define *aliases*
+  '((if . branch)))
+
+(define (or-alias inst)
+  (or (assq-ref *aliases* inst) inst))
+
 (define (lookup-instruction inst)
-  (define inst-obj (assq inst *instruction-set*))
+  (define inst-obj (assq (or-alias inst) *instruction-set*))
   (if inst-obj
       inst-obj
       (error (format #f "could not find instruction ~a" inst))))

tests.scm

@@ -32,7 +32,7 @@
       (=)
       (or)
       (push recur)
-      (branch)
+      (if)
       (return)
     recur
       (dup)