;; Utility functions
+(defun ez-decode-signed-bits (n nbits)
+ (if (= 0 (lsh n (- 1 nbits)))
+ n
+ (- n (lsh 1 nbits))))
+
(defun ez-decode-signed-byte (b)
- (lsh b ))
+ (ez-decode-signed-bits b 8))
+
+(defun ez-decode-signed-word (w)
+ (ez-decode-signed-bits w 16))
+
+(defun binformat (n &optional s)
+ (unless s
+ (setq s ""))
+ (let ((d (/ n 2))
+ (new-s (concat (number-to-string (mod n 2)) s)))
+ (if (= d 0)
+ new-s
+ (binformat d new-s))))
;; Memory
"Load story file into memory."
(with-temp-buffer
(insert-file-contents-literally filename)
- (setq ez-memory (encode-coding-string (buffer-string) 'raw-text))))
+ (setq ez-memory (encode-coding-string (buffer-string) 'raw-text)))
+ 'done)
;; Global variables
;; Object tree
-(defun ez-make-obj (&optional name attribs props parent first-child next-sibling)
- (list name attribs props parent first-child next-sibling))
-
-(defun ez-obj-name (obj) (elt obj 0))
-(defun ez-obj-attribs (obj) (elt obj 1))
-(defun ez-obj-props (obj) (elt obj 2))
-(defun ez-obj-parent (obj) (elt obj 3))
-(defun ez-obj-first-child (obj) (elt obj 4))
-(defun ez-obj-next-sibling (obj) (elt obj 5))
-
(defvar ez-property-defaults nil)
(defun ez-load-property-defaults ()
(dotimes (i 31)
(aset ez-property-defaults i (aref ez-memory (+ ez-objtab-addr (* 2 i))))))
+(defun ez-get-obj-addr (obj-id)
+ (+ ez-objtab-addr (* 2 31) (* 9 (- obj-id 1))))
+
+(defun ez-get-obj-parent (obj-id)
+ (let ((addr (ez-get-obj-addr obj-id)))
+ (ez-mem-ref-byte (+ addr 4))))
+
+(defun ez-get-obj-sibling (obj-id)
+ (let ((addr (ez-get-obj-addr obj-id)))
+ (ez-mem-ref-byte (+ addr 5))))
+
+(defun ez-get-obj-child (obj-id)
+ (let ((addr (ez-get-obj-addr obj-id)))
+ (ez-mem-ref-byte (+ addr 6))))
+
+(defun ez-get-obj-plist-addr (obj-id)
+ (let ((addr (ez-get-obj-addr obj-id)))
+ (ez-mem-ref-word (+ addr 7))))
+
+(defun ez-get-obj-name (obj-id)
+ (let ((plist-addr (ez-get-obj-plist-addr obj-id)))
+ (if (> (ez-mem-ref-byte plist-addr) 0)
+ (ez-get-zstring (+ 1 (ez-get-obj-plist-addr obj-id)))
+ nil)))
+
(defun ez-get-obj (obj-id)
(let ((addr (+ ez-objtab-addr
(* 2 31)
(let ((plist-addr (ez-mem-ref-word (+ addr 7))))
(if (> (ez-mem-ref-byte plist-addr) 0)
(ez-get-zstring (+ 1 plist-addr))
- "")))))
-
+ nil)))))
+
+(defun ez-get-prop-default (prop)
+ (ez-mem-ref-word (+ ez-objtab-addr (* 2 (+ 1 prop)))))
+
+(defun ez-get-prop-len (prop-size-byte)
+ (lsh prop-size-byte -5))
+
+(defun ez-get-prop-num (prop-size-byte)
+ (logand #b00011111 prop-size-byte))
+
+(defun ez-get-obj-prop-addr (obj prop)
+ (let* ((plist-addr (ez-get-obj-plist-addr obj))
+ (prop-addr (+ plist-addr 1 (* 2 (ez-mem-ref-byte plist-addr))))
+ (size-byte (ez-mem-ref-byte prop-addr)))
+ (while (not (or (= size-byte 0)
+ (= prop (ez-get-prop-num size-byte))))
+ (setq prop-addr (+ prop-addr (ez-get-prop-len size-byte) 2)
+ size-byte (ez-mem-ref-byte prop-addr)))
+ prop-addr))
+
+(defun ez-get-obj-prop (obj prop)
+ (let* ((prop-addr (ez-get-obj-prop-addr obj prop))
+ (size-byte (ez-mem-ref-byte prop-addr)))
+ (if (= prop-addr 0)
+ (ez-get-prop-default prop)
+ (let ((prop-len (ez-get-prop-len size-byte))
+ (data-addr (+ prop-addr 1)))
+ (cond
+ ((= prop-len 0)
+ (ez-mem-ref-byte data-addr))
+ ((>= prop-len 1)
+ (ez-mem-ref-word data-addr)))))))
+
+(defun ez-set-obj-prop (obj prop value)
+ (let* ((prop-addr (ez-get-obj-prop-addr obj prop))
+ (size-byte (ez-mem-ref-byte prop-addr)))
+ (cond
+ ((= size-byte 0)
+ (error "Tried to set non-existant property"))
+ ((= (ez-get-prop-len size-byte) 1)
+ (ez-mem-set-byte (+ prop-addr 1) value))
+ (t
+ (ez-mem-set-word (+ prop-addr 1) value)))))
;; Z-strings
((memq char '(1 2 3)) ;Abbreviation
(setq abbrev-char char))
((= char 4)
- (setq cur (mod (+ cur 1) 2)))
+ (setq cur (mod (+ cur 1) 3)))
((= char 5)
- (setq cur (mod (+ 2 (- cur 1)) 2)))
+ (setq cur (mod (+ 3 (- cur 1)) 3)))
(t
(setq s (concat s (substring (elt ez-zstring-alphabets cur)
char (+ char 1))))
operand-types (cdr operands-and-types)))))
(let ((table-row (assoc (list optype opcode) ez-op-table)))
(unless table-row
- (error "Unsupported op" optype opcode))
+ (error "Unsupported op" instr-pc optype opcode operands operand-types))
(let ((mnemonic (elt table-row 1)))
(message "PC:%x Optype:%s Opcode:%x Mnemonic:%s Operands:%s"
instr-pc optype opcode mnemonic operands))
(defun ez-read-var-operands-and-inc ()
(let* ((type-byte (ez-read-pc-byte-and-inc))
- (bleh (message (binformat type-byte)))
(types (let ((type1 (lsh type-byte -6)))
(if (= type1 #b11)
nil
(if (= type 1)
'b
'w))
- types)))))
+ types))))
+
+;; Branches
+
+(defun ez-do-branch (branch)
+ (let* ((branch-byte (ez-read-pc-byte-and-inc))
+ (invert (= 0 (logand branch-byte #b10000000)))
+ (single-byte (= 1 (logand branch-byte #b01000000)))
+ (offset
+ (if single-byte
+ (logand branch-byte #b00111111)
+ (let ((pos (= (logand branch-byte #b00100000) 0))
+ (val (+ (* 256 (logand branch-byte #b00011111))
+ (ez-read-pc-byte-and-inc))))
+ (if pos
+ val
+ (- val 8192))))))
+ (cond
+ ((= offset 0)
+ (ez-op-rfalse))
+ ((= offset 1)
+ (ez-op-rtrue))
+ (t
+ (ez-set-pc (+ (ez-get-pc) offset -2))))))
+
+;; Operations
(defvar ez-op-table
- '(((2op #x14) add ez-op-add)
+ '(((0op #x00) rtrue ez-op-rtrue)
+ ((0op #x01) rfalse ez-op-rfalse)
+ ((1op #x00) jz ez-op-jz)
+ ((1op #x0B) ret ez-op-ret)
+ ((1op #x0C) jump ez-op-jump)
+ ((2op #x0D) store ez-op-store)
+ ((1op #x0E) load ez-op-load)
+ ((var #x01) storew ez-op-storew)
+ ((2op #x01) je ez-op-je)
+ ((2op #x08) or ez-op-or)
+ ((2op #x09) and ez-op-and)
+ ((2op #x14) add ez-op-add)
((2op #x15) sub ez-op-sub)
((2op #x16) mul ez-op-mul)
((2op #x17) div ez-op-div)
((2op #x18) mod ez-op-mod)
- ((var #x00) call_fv ez-op-callf)))
+ ((var #x00) call_fv ez-op-callf)
+ ((1op #x01) get_sibling ez-op-get-sibling)
+ ((1op #x02) get_child ez-op-get-child)
+ ((1op #x03) get_parent ez-op-get-parent)
+ ((var #x03) put_prop ez-op-put-prop)))
+
+(defun ez-op-ret (operands &optional operand-types)
+ (let ((retval (car operands)))
+ (ez-pop-call-stack-frame)
+ (ez-set-var (ez-read-pc-byte-and-inc) retval))
+ t)
+
+(defun ez-op-rtrue (&optional operands operand-types)
+ (ez-op-ret (list 1)))
+
+(defun ez-op-rfalse (&optional operands operand-types)
+ (ez-op-ret (list 0)))
+
+(defun ez-op-jz (operands operand-types)
+ (ez-do-branch (= (car operands) 0))
+ t)
+
+(defun ez-op-je (operands operand-types)
+ (ez-do-branch (memq (car operands) (cdr operands)))
+ t)
+
+(defun ez-op-jump (operands operand-types)
+ (let ((offset (if (eq (car operand-types) 'b)
+ (ez-decode-signed-byte (car operands))
+ (ez-decode-signed-word (car operands)))))
+ (ez-set-pc (+ (ez-get-pc) offset -2)))
+ t)
+
+(defun ez-op-store (operands operand-types)
+ (let ((var (car operands))
+ (a (cadr operands)))
+ (ez-set-var var a))
+ t)
+
+(defun ez-op-load (operands operand-types)
+ (let ((var (car operands)))
+ (ez-set-var (ez-read-pc-byte-and-inc) (ez-get-var var)))
+ t)
+
+(defun ez-op-storew (operands operand-types)
+ (let ((baddr (car operands))
+ (n (cadr operands))
+ (a (caddr operands)))
+ (ez-mem-set-word (+ baddr (* 2 n)) a))
+ t)
+
+(defun ez-op-and (operands operand-types)
+ (let ((a (car operands))
+ (b (cadr operands)))
+ (ez-set-var (ez-read-pc-byte-and-inc) (logand a b)))
+ t)
+
+(defun ez-op-or (operands operand-types)
+ (let ((a (car operands))
+ (b (cadr operands)))
+ (ez-set-var (ez-read-pc-byte-and-inc) (logior a b)))
+ t)
(defun ez-op-add (operands operand-types)
(let ((a (car operands))
(b (cadr operands)))
- (ez-set-var (ez-read-pc-byte-and-inc) (mod (+ a b) #x10000))))
+ (ez-set-var (ez-read-pc-byte-and-inc) (mod (+ a b) #x10000)))
+ t)
(defun ez-op-sub (operands operand-types)
(let ((a (car operands))
(b (cadr operands)))
- (ez-set-var (ez-read-pc-byte-and-inc) (mod (+ (- a b) #x10000) #x10000))))
+ (ez-set-var (ez-read-pc-byte-and-inc) (mod (+ (- a b) #x10000) #x10000)))
+ t)
(defun ez-op-mul (a b)
(let ((a (car operands))
(b (cadr operands)))
- (ez-set-var (ez-read-pc-byte-and-inc) (mod (* a b) #x10000))))
+ (ez-set-var (ez-read-pc-byte-and-inc) (mod (* a b) #x10000)))
+ t)
-(defun ez-op-div (a b))
+(defun ez-op-div (a b)
+ (error "Not implemented"))
-(defun ez-op-mod (a b))
+(defun ez-op-mod (a b)
+ (error "Not implemented"))
(defun ez-op-callf (operands operand-types)
(let* ((raddr (car operands))
(ez-set-local-var (+ i 1) (ez-mem-ref-word (+ r 1 (* 2 i)))))))
t)
+(defun ez-op-get-sibling (operands operand-types)
+ (let ((sib (ez-get-obj-sibling (car operands))))
+ (ez-set-var (ez-read-pc-byte-and-inc) sib)
+ (ez-do-branch (> sib 0))))
+
+(defun ez-op-get-child (operands operand-types)
+ (let ((child (ez-get-obj-child (car operands))))
+ (ez-set-var (ez-read-pc-byte-and-inc) child)
+ (ez-do-branch (> child 0))))
+
+(defun ez-op-get-parent (operands operand-types)
+ (let ((parent (ez-get-obj-parent (car operands))))
+ (ez-set-var (ez-read-pc-byte-and-inc) parent)
+ (ez-do-branch (> parent 0))))
+
+(defun ez-op-put-prop (operands operand-types)
+ (let* ((obj (car operands))
+ (prop (cadr operands))
+ (a (caddr operands)))
+ (ez-set-obj-prop obj prop a)))
+
;; Main
(defun ez-run (filename)
(ez-parse-header)
(setq ez-call-stack (list (ez-make-call-stack-frame ez-start-pc)))
- (while (ez-execute-inst)))
+ (while (ez-execute-instr)))
;; Scratch
-(ez-load-file "zork1.z3")
-(ez-parse-header)
-(setq ez-call-stack (list (ez-make-call-stack-frame ez-start-pc)))
-(ez-execute-instr)
-ez-call-stack
-
-(defun binformat (n &optional s)
- (unless s
- (setq s ""))
- (let ((d (/ n 2))
- (new-s (concat (number-to-string (mod n 2)) s)))
- (if (= d 0)
- new-s
- (binformat d new-s))))
-
+;; (ez-load-file "zork1.z3")
+;; (ez-parse-header)
+;; (setq ez-call-stack (list (ez-make-call-stack-frame ez-start-pc)))
+;; (while (ez-execute-instr))
+(ez-run "zork1.z3")
;;; ez.el ends here
The Lambda Lab / projects / ez.git / blobdiff