;;; Code:
-;; Character set tables
+;; 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)
+ (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
(ez-get-var (ez-read-pc-byte-and-inc)))
(defun ez-execute-instr ()
- (let ((opbyte (ez-read-pc-byte-and-inc))
+ (let ((instr-pc (ez-get-pc))
+ (opbyte (ez-read-pc-byte-and-inc))
(optype)
(opcode nil)
(operands))
(setq optype '2op
opcode opbyte
operands (list (ez-read-pc-byte-and-inc)
- (ez-read-pc-byte-and-inc))))
+ (ez-read-pc-byte-and-inc))
+ operand-types '(b b)))
((<= #x20 opbyte #x3F)
(setq optype '2op
opcode (- opbyte #x20)
operands (list (ez-read-pc-byte-and-inc)
- (ez-read-pc-var-and-inc))))
+ (ez-read-pc-var-and-inc))
+ operand-types '(b w)))
((<= #x40 opbyte #x5F)
(setq optype '2op
opcode (- opbyte #x40)
operands (list (ez-read-pc-var-and-inc)
- (ez-read-pc-byte-and-inc))))
+ (ez-read-pc-byte-and-inc))
+ operand-types '(w b)))
((<= #x60 opbyte #x7F)
(setq optype '2op
opcode (- opbyte #x60)
operands (list (ez-read-pc-var-and-inc)
- (ez-read-pc-var-and-inc))))
+ (ez-read-pc-var-and-inc))
+ operand-types '(w w)))
((<= #x80 opbyte #x8F)
(setq optype '1op
opcode (- opbyte #x80)
- operands (list (ez-read-pc-word-and-inc))))
+ operands (list (ez-read-pc-word-and-inc))
+ operand-types '(w)))
((<= #x90 opbyte #x9F)
(setq optype '1op
opcode (- opbyte #x90)
- operands (list (ez-read-pc-byte-and-inc))))
+ operands (list (ez-read-pc-byte-and-inc))
+ operand-types '(b)))
((<= #xA0 opbyte #xAF)
(setq optype '1op
opcode (- opbyte #xa0)
- operands (list (ez-read-pc-var-and-inc))))
+ operands (list (ez-read-pc-var-and-inc))
+ operand-types '(w)))
((<= #xB0 opbyte #xBF)
(setq optype '0op
opcode (- opbyte #xb0)))
(error "Unsupported op" opbyte))
((<= #xE0 opbyte #xFF)
(setq optype 'var
- opcode (- opbyte #xe0)
- operands (ez-read-var-operands-and-inc))))
+ opcode (- opbyte #xe0))
+ (let ((operands-and-types (ez-read-var-operands-and-inc)))
+ (setq operands (car operands-and-types)
+ operand-types (cdr operands-and-types)))))
(let ((table-row (assoc (list optype opcode) ez-op-table)))
(unless table-row
(error "Unsupported op" optype opcode))
(let ((mnemonic (elt table-row 1)))
- (message "Optype:%s Opcode:%x Mnemonic:%s Operands:%s"
- optype opcode mnemonic operands))
- (apply (elt table-row 2) operands))))
+ (message "PC:%x Optype:%s Opcode:%x Mnemonic:%s Operands:%s"
+ instr-pc optype opcode mnemonic operands))
+ (funcall (elt table-row 2) operands operand-types))))
(defun ez-read-var-operands-and-inc ()
(let* ((type-byte (ez-read-pc-byte-and-inc))
nil
(list type4)))))))))))))
(operands nil))
- (mapcar
- (lambda (type)
- (cond
- ((= type 0) (ez-read-pc-word-and-inc))
- ((= type 1) (ez-read-pc-byte-and-inc))
- ((= type 2) (ez-read-pc-var-and-inc))))
- types)))
+ (cons
+ (mapcar
+ (lambda (type)
+ (cond
+ ((= type 0) (ez-read-pc-word-and-inc))
+ ((= type 1) (ez-read-pc-byte-and-inc))
+ ((= type 2) (ez-read-pc-var-and-inc))))
+ types)
+ (mapcar
+ (lambda (type)
+ (if (= type 1)
+ 'b
+ 'w))
+ 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
- '(((var #x0) call_fv ez-op-callf)))
+ '(((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)))
+
+(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-callf (raddr &rest operands)
- (let* ((r (* 2 raddr))
+(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)))
+ 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)))
+ 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)))
+ t)
+
+(defun ez-op-div (a b)
+ (error "Not implemented"))
+
+(defun ez-op-mod (a b)
+ (error "Not implemented"))
+
+(defun ez-op-callf (operands operand-types)
+ (let* ((raddr (car operands))
+ (call-operands (cdr operands))
+ (r (* 2 raddr))
(L (ez-mem-ref-byte r))
- (n (length operands))
+ (n (length call-operands))
(new-pc (+ r 1 (* L 2))))
(ez-add-call-stack-frame new-pc)
(dotimes (i L)
(if (< i n)
- (ez-set-local-var (+ i 1) (elt operands i))
+ (ez-set-local-var (+ i 1) (elt call-operands i))
(ez-set-local-var (+ i 1) (ez-mem-ref-word (+ r 1 (* 2 i)))))))
t)
(ez-parse-header)
(setq ez-call-stack (list (ez-make-call-stack-frame ez-start-pc)))
(ez-execute-instr)
+
+(binformat #x97)
+"10010111"
+
+
ez-call-stack
+((28281 nil [33807 0 180 47872 0 0 0 0 0 0 0 0 ...] nil) (22022 nil [33807 65535 0 0 0 0 0 0 0 0 0 0 ...] nil) (20715 nil [0 0 0 0 0 0 0 0 0 0 0 0 ...] nil))
+
+((22049 nil [33807 0 180 47872 0 0 0 0 0 0 0 0 ...] nil) (22022 nil [33807 65535 0 0 0 0 0 0 0 0 0 0 ...] nil) (20715 nil [0 0 0 0 0 0 0 0 0 0 0 0 ...] nil))
+
+
+
+
+
+
+
+
-(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))))