c64-livecoding/wip-duuqnd/compiler.lisp

84 lines
2.6 KiB
Common Lisp

(defpackage #:compiler
(:use #:cl))
(in-package #:compiler)
(defvar *label-counter* 0)
(defun genlabel (&optional (prefix "L"))
(format nil "~A~D" prefix (incf *label-counter*)))
(defmacro format-inst (destination control-string &rest format-arguments)
`(format ,destination "~C~A~%" #\Tab (format nil ,control-string ,@format-arguments)))
(defclass reference () ())
(defclass reference-constant (reference)
((%value :accessor ref-value :initarg :value)))
(defmethod dereference ((ref reference-constant))
(format-inst t "LDA #~D" (ref-value ref)))
(defclass reference-variable (reference)
((%index :accessor ref-index :initarg :index)))
(defmethod dereference ((ref reference-variable))
(format-inst t "LDY #~D" (ref-index ref))
(format-inst t "LDA VARVEC,Y"))
(defclass node ()
((%next :accessor next :accessor normal-next)))
(defclass node-call (node)
((%callee :accessor callee :initarg :callee)
(%arguments :accessor arguments :initarg :arguments)))
(defmethod generate-code ((node node-call))
(loop :for ref :in (arguments node)
:for index :from 0
:do (dereference ref)
:do (format-inst t "STA ARGVEC+~D" index))
(format-inst t "JSR ~A" (callee node)))
(defclass node-branch (node)
((%branch-next :accessor branch-next :initarg :branch-next)))
(defmethod generate-code ((node node-branch))
(let ((else-label (genlabel "ELSE")))
(format-inst t "LDA RESULT")
(format-inst t "BNE ~A" else-label)
;; The THEN branch
(generate-code (branch-next node))
;; The ELSE branch
(format t "~%~A:~%" else-label)))
(defclass node-dotimes (node)
((%spot-ref :accessor stop-ref :initarg :stop-ref
:documentation "A reference giving a value of how many times to run the loop.")
(%loopee-node :accessor loopee-node :initarg :loopee-node)))
(defmethod generate-code ((node node-dotimes))
(format-inst t "TXA")
(format-inst t "PHA")
(let ((loop-label (genlabel "LOOPBACK")))
(dereference (stop-ref node))
(format-inst t "TAX")
(format t "~%~A:~%" loop-label)
(generate-code (loopee-node node))
(format-inst t "DEX")
(format-inst t "BNE ~A" loop-label))
(format-inst t "PLA")
(format-inst t "TAX"))
(defun make-call (callee args)
(let ((arguments
(loop :for (constp value) :in args
:with index := -1
:if constp
:collect (make-instance 'reference-constant :value value)
:else
:collect (make-instance 'reference-variable :index (incf index)))))
(make-instance 'node-call :callee callee
:arguments arguments)))