57 lines
915 B
Scheme
57 lines
915 B
Scheme
;; Note that this is scheme syntax wrapping asm for a stack machine
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(variable eom 1024)
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;; These need to be initialized with the runtime
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(variable scan 0)
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(variable free 0)
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(variable root 0)
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(variable old 0)
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(variable new 0)
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(push main)
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(jmp)
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alloc ;; ( -- p)
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;; Test if free will go beyond eom
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(ref free)
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(dup) ; ( -- free free)
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(push 8)
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(+)
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(dup) ; ( -- free free+8 free+8)
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(ref eom)
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(<) ; ( -- free free+8 (free+8 < eom))
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(push alloc-do-gc)
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(if)
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;; write free+8 to free
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(set! free)
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;; return the old free, it is memory the program can use
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(return)
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alloc-do-gc
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;; Empty the stack
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(drop)
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(drop)
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;; Run garbage collection
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(push gc-start)
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(call)
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;; Tail-call allocation
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(push alloc)
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(jmp)
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gc-start ;; ( -- )
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; Move scan & free to start of new memory
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(ref new)
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(dup)
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(set! free)
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(set! scan)
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(ref root)
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(push relocate-object)
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(call)
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(push gc-loop)
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(call)
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(return)
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relocate-object ;; (o -- )
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;; TODO
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main
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;; TODO
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