;; Compilation of Lisp code into byte code.
;; Copyright (C) 1985 Richard M. Stallman.

;; This file is part of GNU Emacs.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY.  No author or distributor
;; accepts responsibility to anyone for the consequences of using it
;; or for whether it serves any particular purpose or works at all,
;; unless he says so in writing.  Refer to the GNU Emacs General Public
;; License for full details.

;; Everyone is granted permission to copy, modify and redistribute
;; GNU Emacs, but only under the conditions described in the
;; GNU Emacs General Public License.   A copy of this license is
;; supposed to have been given to you along with GNU Emacs so you
;; can know your rights and responsibilities.  It should be in a
;; file named COPYING.  Among other things, the copyright notice
;; and this notice must be preserved on all copies.


(defvar byte-compile-constnum -1
  "Transfer vector index of last constant allocated.")
(defvar byte-compile-constants nil
  "Alist describing contents to put in transfer vector.
Each element is (CONTENTS . INDEX)")
(defvar byte-compile-macro-environment nil
  "Alist of (MACRONAME . DEFINITION) macros defined in the file
which is being compiled.")
(defvar byte-compile-pc 0
  "Index in byte string to store next opcode at.")
(defvar byte-compile-output nil
  "Alist describing contents to put in byte code string.
Each element is (INDEX . VALUE)")
(defvar byte-compile-depth 0
  "Current depth of execution stack.")
(defvar byte-compile-maxdepth 0
  "Maximum depth of execution stack.")

(defconst byte-varref 8
  "Byte code opcode for variable reference.")
(defconst byte-varset 16
  "Byte code opcode for setting a variable.")
(defconst byte-varbind 24
  "Byte code opcode for binding a variable.")
(defconst byte-call 32
  "Byte code opcode for calling a function.")
(defconst byte-unbind 40
  "Byte code opcode for unbinding special bindings.")

(defconst byte-constant 192
  "Byte code opcode for reference to a constant.")
(defconst byte-constant-limit 64
  "Maximum index usable in  byte-constant  opcode.")

(defconst byte-constant2 129
  "Byte code opcode for reference to a constant with vector index >= 0100.")

(defconst byte-goto 130
  "Byte code opcode for unconditional jump")

(defconst byte-goto-if-nil 131
  "Byte code opcode for pop value and jump if it's nil.")

(defconst byte-goto-if-not-nil 132
  "Byte code opcode for pop value and jump if it's not nil.")

(defconst byte-goto-if-nil-else-pop 133
  "Byte code opcode for examine top-of-stack, jump and don't pop it if it's nil,
otherwise pop it.")

(defconst byte-goto-if-not-nil-else-pop 134
  "Byte code opcode for examine top-of-stack, jump and don't pop it if it's not nil,
otherwise pop it.")

(defconst byte-return 135
  "Byte code opcode for pop value and return it from byte code interpreter.")

(defconst byte-discard 136
  "Byte code opcode to discard one value from stack.")

(defconst byte-dup 137
  "Byte code opcode to duplicate the top of the stack.")

(defconst byte-save-excursion 138
  "Byte code opcode to make a binding to record the buffer, point and mark.")

(defconst byte-save-window-excursion 139
  "Byte code opcode to make a binding to record entire window configuration.")

(defconst byte-save-restriction 140
  "Byte code opcode to make a binding to record the current buffer clipping restrictions.")

(defconst byte-catch 141
  "Byte code opcode for catch.  Takes, on stack, the tag and an expression for the body.")

(defconst byte-unwind-protect 142
  "Byte code opcode for unwind-protect.  Takes, on stack, an expression for the body
and an expression for the unwind-action.")

(defconst byte-condition-case 143
  "Byte code opcode for condition-case.  Takes, on stack, the variable to bind,
an expression for the body, and a list of clauses.")

(defconst byte-temp-output-buffer-setup 144
  "Byte code opcode for entry to with-output-to-temp-buffer.
Takes, on stack, the buffer name.
Binds standard-output and does some other things.
Returns with temp buffer on the stack in place of buffer name.")

(defconst byte-temp-output-buffer-show 145
  "Byte code opcode for exit from with-output-to-temp-buffer.
Expects the temp buffer on the stack underneath value to return.
Pops them both, then pushes the value back on.
Unbinds standard-output and makes the temp buffer visible.")

(defconst byte-nth 56)
(defconst byte-symbolp 57)
(defconst byte-consp 58)
(defconst byte-stringp 59)
(defconst byte-listp 60)
(defconst byte-eq 61)
(defconst byte-memq 62)
(defconst byte-not 63)
(defconst byte-car 64)
(defconst byte-cdr 65)
(defconst byte-cons 66)
(defconst byte-list1 67)
(defconst byte-list2 68)
(defconst byte-list3 69)
(defconst byte-list4 70)
(defconst byte-length 71)
(defconst byte-aref 72)
(defconst byte-aset 73)
(defconst byte-symbol-value 74)
(defconst byte-symbol-function 75)
(defconst byte-set 76)
(defconst byte-fset 77)
(defconst byte-get 78)
(defconst byte-substring 79)
(defconst byte-concat2 80)
(defconst byte-concat3 81)
(defconst byte-concat4 82)
(defconst byte-sub1 83)
(defconst byte-add1 84)
(defconst byte-eqlsign 85)
(defconst byte-gtr 86)
(defconst byte-lss 87)
(defconst byte-leq 88)
(defconst byte-geq 89)
(defconst byte-diff 90)
(defconst byte-negate 91)
(defconst byte-plus 92)
(defconst byte-max 93)
(defconst byte-min 94)

(defconst byte-point 96)
(defconst byte-mark 97)
(defconst byte-goto-char 98)
(defconst byte-insert 99)
(defconst byte-point-max 100)
(defconst byte-point-min 101)
(defconst byte-char-after 102)
(defconst byte-following-char 103)
(defconst byte-preceding-char 104)
(defconst byte-current-column 105)
(defconst byte-indent-to 106)
(defconst byte-scan-buffer 107)
(defconst byte-eolp 108)
(defconst byte-eobp 109)
(defconst byte-bolp 110)
(defconst byte-bobp 111)
(defconst byte-current-buffer 112)
(defconst byte-set-buffer 113)
(defconst byte-read-char 114)
(defconst byte-set-mark 115)
(defconst byte-interactive-p 116)

(defun byte-recompile-directory (directory &optional arg)
  "Recompile every .el file in DIRECTORY that needs recompilation.
This is if a .elc file exists but is older than the .el file.
If the .elc file does not exist, offer to compile the .el file
only if a prefix argument has been specified." 
  (interactive "DByte recompile directory: \nP")
  (save-some-buffers)
  (setq directory (expand-file-name directory))
  (let ((files (directory-files directory))
	(count 0)
	source)
    (while files
      (if (and (string-match ".el$" (car files))
	       (not (auto-save-file-name-p (car files)))
	       (setq source (expand-file-name (car files) directory))
	       (if (file-exists-p (concat source "c"))
		   (file-newer-than-file-p source (concat source "c"))
		   (and arg (y-or-n-p (concat "Compile " source "? ")))))
	  (progn (byte-compile-file source)
		 (setq count (1+ count))))
      (setq files (cdr files)))
    (message "Done (Total of %d file%s compiled)"
	     count (if (= count 1) "" "s"))))

(defun file-newer-than-file-p (file1 file2)
  "Return t if FILE1 modified more recently than FILE2."
  (let ((mtime1 (car (nthcdr 5 (file-attributes file1))))
	(mtime2 (car (nthcdr 5 (file-attributes file2)))))
    (or (> (car mtime1) (car mtime2))
	(and (= (car mtime1) (car mtime2))
	     (> (car (cdr mtime1)) (car (cdr mtime2)))))))

(defun byte-compile-file (filename)
  "Compile a file of Lisp code named FILENAME into a file of byte code.
The output file's name is made by appending \"c\" to the end of FILENAME."
  (interactive "fByte compile file: ")
  ;; Expand now so we get the current buffer's defaults
  (setq filename (expand-file-name filename))
  (message "Compiling %s..." filename)
  (let ((inbuffer (get-buffer-create " *Compiler Input*"))
	(outbuffer (get-buffer-create " *Compiler Output*"))
	(byte-compile-macro-environment nil)

	(case-fold-search nil) ;I thought this was lisp, not unix!
	sexp)
    (save-excursion
      (set-buffer inbuffer)
      (erase-buffer)
      (insert-file-contents filename)
      (goto-char 1)
      (set-buffer outbuffer)
      (emacs-lisp-mode)
      (erase-buffer)
      (while (save-excursion
	       (set-buffer inbuffer)
	       (while (progn (skip-chars-forward " \t\n\^l")
			     (looking-at ";"))
		 (forward-line 1))
	       (not (eobp)))
	(setq sexp (read inbuffer))
	(print (byte-compile-file-form sexp) outbuffer))
      (set-buffer outbuffer)
      (goto-char 1)
      (while (search-forward "\n(" nil t)
	(cond ((looking-at "defun \\|autoload ")
	       (forward-sexp 3)
	       (skip-chars-forward " ")
	       (if (looking-at "\"")
		   (progn (forward-char 1)
			  (insert "\\\n"))))))
      (write-region 1 (point-max) (concat filename "c"))
      (kill-buffer (current-buffer))
      (kill-buffer inbuffer)))
  t)


(defun byte-compile-file-form (form)
  (if (memq (car-safe form) '(defun defmacro))
      (let* ((name (car (cdr form)))
	     (tem (assq name byte-compile-macro-environment)))
	(if (eq (car form) 'defun)
	    (progn
	      (message "Compiling %s (%s)..." filename (nth 1 form))
	      (cond (tem (setcdr tem nil))
		    ((and (fboundp name)
			  (eq (car-safe (symbol-function name)) 'macro))
		     ;; shadow existing macro definition
		     (setq byte-compile-macro-environment
			   (cons (cons name nil)
				 byte-compile-macro-environment))))
	      (prog1 (cons 'defun (byte-compile-lambda (cdr form)))
		     (if (not noninteractive)
			 (message "Compiling %s..." filename))))
	  ;; defmacro
	  (if tem
	      (setcdr tem (cons 'lambda (cdr (cdr form))))
	    (setq byte-compile-macro-environment
		  (cons (cons name (cons 'lambda (cdr (cdr form))))
			byte-compile-macro-environment)))
	  (cons 'defmacro (byte-compile-lambda (cdr form)))))
    form))

(defun byte-compile (funname)
  "Byte-compile the definition of function FUNNAME (a symbol)."
  (if (and (fboundp funname)
	   (eq (car-safe (symbol-function funname)) 'lambda))
      (fset funname (byte-compile-lambda (symbol-function funname)))))

(defun byte-compile-lambda (fun)
  (let* ((bodyptr (cdr fun))
	 (int (assq 'interactive (cdr bodyptr)))
	 newbody)
    ;; Skip doc string.
    (if (stringp (car (cdr bodyptr)))
	(setq bodyptr (cdr bodyptr)))
    (setq newbody (list (byte-compile-top-level
			  (cons 'progn (cdr bodyptr)))))
    (if int
	(setq newbody (cons (if (or (stringp (car (cdr int)))
				    (null (car (cdr int))))
				int
			      (list 'interactive
				    (byte-compile-top-level (car (cdr int)))))
			    newbody)))
    (if (not (eq bodyptr (cdr fun)))
	(setq newbody (cons (nth 2 fun) newbody)))
    (cons (car fun) (cons (car (cdr fun)) newbody))))

(defun byte-compile-top-level (form)
  (let ((byte-compile-constants nil)
	(byte-compile-constnum nil)
	(byte-compile-pc 0)
	(byte-compile-depth 0)
	(byte-compile-maxdepth 0)
	(byte-compile-output nil)
	(byte-compile-string nil)
	(byte-compile-vector nil))
    (let ((vars (nreverse (byte-compile-find-vars form)))
	  (i -1))
      (while vars
	(setq i (1+ i))
	(setq byte-compile-constants (cons (cons (car vars) i)
					   byte-compile-constants))
	(setq vars (cdr vars)))
      (setq byte-compile-constnum i))
    (byte-compile-form form)
    (byte-compile-out 'byte-return 0)
    (setq byte-compile-vector (make-vector (1+ byte-compile-constnum)
					   nil))
    (while byte-compile-constants
      (aset byte-compile-vector (cdr (car byte-compile-constants))
	    (car (car byte-compile-constants)))
      (setq byte-compile-constants (cdr byte-compile-constants)))
    (setq byte-compile-string (make-string byte-compile-pc 0))
    (while byte-compile-output
      (aset byte-compile-string (car (car byte-compile-output))
	    (cdr (car byte-compile-output)))
      (setq byte-compile-output (cdr byte-compile-output)))
    (list 'byte-code byte-compile-string
		     byte-compile-vector byte-compile-maxdepth)))

(defun byte-compile-find-vars (form)
  (let ((all-vars nil))
    (byte-compile-find-vars-1 form)
    all-vars))

(defun byte-compile-find-vars-1 (form)
  (cond ((symbolp form)
	 (if (not (memq form all-vars))
	     (setq all-vars (cons form all-vars))))
	((or (not (consp form)) (eq (car form) 'quote))
	 nil)
	((memq (car form) '(let let*))
	 (let ((binds (car (cdr form)))
	       (body (cdr (cdr form))))
	   (while binds
	     (if (symbolp (car binds))
		 (if (not (memq (car binds) all-vars))
		     (setq all-vars (cons (car binds) all-vars)))
	       (if (consp (car binds))
		   (progn
		     (if (not (memq (car (car binds)) all-vars))
			 (setq all-vars (cons (car (car binds)) all-vars)))
		     (byte-compile-find-vars-1 (car (cdr (car binds)))))))
	     (setq binds (cdr binds)))
	   (while body
	     (byte-compile-find-vars-1 (car body))
	     (setq body (cdr body)))))
	((eq (car form) 'cond)
	 (let ((clauses (cdr form)))
	   (while clauses
	     (let ((body (car clauses)))
	       (while body
		 (byte-compile-find-vars-1 (car body))
		 (setq body (cdr body))))
	     (setq clauses (cdr clauses)))))
	((not (eq form (setq form (macroexpand form byte-compile-macro-environment))))
	 (byte-compile-find-vars-1 form))
	(t
	 (let ((body (if (symbolp (car form)) (cdr form) form)))
	   (while body
	     (byte-compile-find-vars-1 (car body))
	     (setq body (cdr body)))))))

;; This is the recursive entry point for compiling each subform of an expression.

;; Note that handler functions SHOULD NOT increment byte-compile-depth
;; for the values they are returning!  That is done on return here.
;; Handlers should make sure that the depth on exit is the same as
;; it was when the handler was called.

(defun byte-compile-form (form)
  (setq form (macroexpand form byte-compile-macro-environment))
  (if (symbolp form)
      (byte-compile-variable-ref 'byte-varref form)
    (if (not (consp form))
	(byte-compile-constant form)
      (let ((handler (get (car form) 'byte-compile)))
	(if handler
	    (funcall handler form)
	  (byte-compile-push-constant (car form))
	  (let ((copy (cdr form)))
	    (while copy (byte-compile-form (car copy)) (setq copy (cdr copy))))
	  (byte-compile-out 'byte-call (length (cdr form)))
	  (setq byte-compile-depth (- byte-compile-depth (length (cdr form))))))))
  (setq byte-compile-maxdepth
	(max byte-compile-maxdepth
	     (setq byte-compile-depth (1+ byte-compile-depth)))))

(defun byte-compile-variable-ref (base-op var)
  (let ((data (assq var byte-compile-constants)))
    (if data
	(byte-compile-out base-op (cdr data))
      (error (format "Variable %s seen on pass 2 of byte compiler but not pass 1"
		     (prin1-to-string var))))))

;; Use this when the value of a form is a constant,
;; because byte-compile-depth will be incremented accordingly
;; on return to byte-compile-form, so it should not be done by the handler.
(defun byte-compile-constant (const)
  (let ((data (if (stringp const)
		  (assoc const byte-compile-constants)
		(assq const byte-compile-constants))))
    (if data
	(byte-compile-out-const (cdr data))
      (setq byte-compile-constants
	    (cons (cons const (setq byte-compile-constnum (1+ byte-compile-constnum)))
		  byte-compile-constants))
      (byte-compile-out-const byte-compile-constnum))))

;; Use this for a constant that is not the value of its containing form.
;; Note that the calling function must explicitly decrement byte-compile-depth
;; (or perhaps call byte-compile-discard to do so)
;; for the word pushed by this function.
(defun byte-compile-push-constant (const)
  (byte-compile-constant const)
  (setq byte-compile-maxdepth
	(max byte-compile-maxdepth
	     (setq byte-compile-depth (1+ byte-compile-depth)))))

;; Compile those primitive ordinary functions
;; which have special byte codes just for speed.

(put 'point 'byte-compile 'byte-compile-no-args)
(put 'point 'byte-opcode 'byte-point)

(put 'dot 'byte-compile 'byte-compile-no-args)
(put 'dot 'byte-opcode 'byte-point)

(put 'mark 'byte-compile 'byte-compile-no-args)
(put 'mark 'byte-opcode 'byte-mark)

(put 'point-max 'byte-compile 'byte-compile-no-args)
(put 'point-max 'byte-opcode 'byte-point-max)

(put 'point-min 'byte-compile 'byte-compile-no-args)
(put 'point-min 'byte-opcode 'byte-point-min)

(put 'dot-max 'byte-compile 'byte-compile-no-args)
(put 'dot-max 'byte-opcode 'byte-point-max)

(put 'dot-min 'byte-compile 'byte-compile-no-args)
(put 'dot-min 'byte-opcode 'byte-point-min)

(put 'following-char 'byte-compile 'byte-compile-no-args)
(put 'following-char 'byte-opcode 'byte-following-char)

(put 'preceding-char 'byte-compile 'byte-compile-no-args)
(put 'preceding-char 'byte-opcode 'byte-preceding-char)

(put 'current-column 'byte-compile 'byte-compile-no-args)
(put 'current-column 'byte-opcode 'byte-current-column)

(put 'eolp 'byte-compile 'byte-compile-no-args)
(put 'eolp 'byte-opcode 'byte-eolp)

(put 'eobp 'byte-compile 'byte-compile-no-args)
(put 'eobp 'byte-opcode 'byte-eobp)

(put 'bolp 'byte-compile 'byte-compile-no-args)
(put 'bolp 'byte-opcode 'byte-bolp)

(put 'bobp 'byte-compile 'byte-compile-no-args)
(put 'bobp 'byte-opcode 'byte-bobp)

(put 'current-buffer 'byte-compile 'byte-compile-no-args)
(put 'current-buffer 'byte-opcode 'byte-current-buffer)

(put 'read-char 'byte-compile 'byte-compile-no-args)
(put 'read-char 'byte-opcode 'byte-read-char)


(put 'symbolp 'byte-compile 'byte-compile-one-arg)
(put 'symbolp 'byte-opcode 'byte-symbolp)

(put 'consp 'byte-compile 'byte-compile-one-arg)
(put 'consp 'byte-opcode 'byte-consp)

(put 'stringp 'byte-compile 'byte-compile-one-arg)
(put 'stringp 'byte-opcode 'byte-stringp)

(put 'listp 'byte-compile 'byte-compile-one-arg)
(put 'listp 'byte-opcode 'byte-listp)

(put 'not 'byte-compile 'byte-compile-one-arg)
(put 'not 'byte-opcode 'byte-not)

(put 'null 'byte-compile 'byte-compile-one-arg)
(put 'null 'byte-opcode 'byte-not)

(put 'car 'byte-compile 'byte-compile-one-arg)
(put 'car 'byte-opcode 'byte-car)

(put 'cdr 'byte-compile 'byte-compile-one-arg)
(put 'cdr 'byte-opcode 'byte-cdr)

(put 'length 'byte-compile 'byte-compile-one-arg)
(put 'length 'byte-opcode 'byte-length)

(put 'symbol-value 'byte-compile 'byte-compile-one-arg)
(put 'symbol-value 'byte-opcode 'byte-symbol-value)

(put 'symbol-function 'byte-compile 'byte-compile-one-arg)
(put 'symbol-function 'byte-opcode 'byte-symbol-function)

(put '1+ 'byte-compile 'byte-compile-one-arg)
(put '1+ 'byte-opcode 'byte-add1)

(put '1- 'byte-compile 'byte-compile-one-arg)
(put '1- 'byte-opcode 'byte-sub1)

(put 'goto-char 'byte-compile 'byte-compile-one-arg)
(put 'goto-char 'byte-opcode 'byte-goto-char)

(put 'char-after 'byte-compile 'byte-compile-one-arg)
(put 'char-after 'byte-opcode 'byte-char-after)

(put 'set-buffer 'byte-compile 'byte-compile-one-arg)
(put 'set-buffer 'byte-opcode 'byte-set-buffer)

(put 'set-mark 'byte-compile 'byte-compile-one-arg)
(put 'set-mark 'byte-opcode 'byte-set-mark)

(put 'interactive-p 'byte-compile 'byte-compile-one-arg)
(put 'interactive-p 'byte-opcode 'byte-interactive-p)


(put 'eq 'byte-compile 'byte-compile-two-args)
(put 'eq 'byte-opcode 'byte-eq)

(put 'memq 'byte-compile 'byte-compile-two-args)
(put 'memq 'byte-opcode 'byte-memq)

(put 'cons 'byte-compile 'byte-compile-two-args)
(put 'cons 'byte-opcode 'byte-cons)

(put 'aref 'byte-compile 'byte-compile-two-args)
(put 'aref 'byte-opcode 'byte-aref)

(put 'set 'byte-compile 'byte-compile-two-args)
(put 'set 'byte-opcode 'byte-set)

(put 'fset 'byte-compile 'byte-compile-two-args)
(put 'fset 'byte-opcode 'byte-fset)

(put '= 'byte-compile 'byte-compile-two-args)
(put '= 'byte-opcode 'byte-eqlsign)

(put '< 'byte-compile 'byte-compile-two-args)
(put '< 'byte-opcode 'byte-lss)

(put '> 'byte-compile 'byte-compile-two-args)
(put '> 'byte-opcode 'byte-gtr)

(put '<= 'byte-compile 'byte-compile-two-args)
(put '<= 'byte-opcode 'byte-leq)

(put '>= 'byte-compile 'byte-compile-two-args)
(put '>= 'byte-opcode 'byte-geq)

(put 'get 'byte-compile 'byte-compile-two-args)
(put 'get 'byte-opcode 'byte-get)

(put 'nth 'byte-compile 'byte-compile-two-args)
(put 'nth 'byte-opcode 'byte-nth)

(put 'aset 'byte-compile 'byte-compile-three-args)
(put 'aset 'byte-opcode 'byte-aset)

(put 'substring 'byte-compile 'byte-compile-three-args)
(put 'substring 'byte-opcode 'byte-substring)

(put 'scan-buffer 'byte-compile 'byte-compile-three-args)
(put 'scan-buffer 'byte-opcode 'byte-scan-buffer)

(defun byte-compile-no-args (form)
  (byte-compile-out (symbol-value (get (car form) 'byte-opcode)) 0))

(defun byte-compile-one-arg (form)
  (byte-compile-form (or (car (cdr form)) ''nil))  ;; Push the argument
  (setq byte-compile-depth (1- byte-compile-depth))
  (byte-compile-out (symbol-value (get (car form) 'byte-opcode)) 0))

(defun byte-compile-two-args (form)
  (byte-compile-form (or (car (cdr form)) ''nil))  ;; Push the arguments
  (byte-compile-form (or (nth 2 form) ''nil))
  (setq byte-compile-depth (- byte-compile-depth 2))
  (byte-compile-out (symbol-value (get (car form) 'byte-opcode)) 0))

(defun byte-compile-three-args (form)
  (byte-compile-form (or (car (cdr form)) ''nil))  ;; Push the arguments
  (byte-compile-form (or (nth 2 form) ''nil))
  (byte-compile-form (or (nth 3 form) ''nil))
  (setq byte-compile-depth (- byte-compile-depth 3))
  (byte-compile-out (symbol-value (get (car form) 'byte-opcode)) 0))

(put 'list 'byte-compile 'byte-compile-list)
(defun byte-compile-list (form)
  (let ((len (length form)))
    (if (= len 1)
	(byte-compile-constant nil)
      (if (< len 6)
	  (let ((args (cdr form)))
	   (while args
	     (byte-compile-form (car args))
	     (setq args (cdr args)))
	   (setq byte-compile-depth (- byte-compile-depth (1- len)))
	   (byte-compile-out (symbol-value
			      (nth (- len 2)
				   '(byte-list1 byte-list2 byte-list3 byte-list4)))
			     0))
	(byte-compile-normal-call form)))))

(put 'concat 'byte-compile 'byte-compile-concat)
(defun byte-compile-concat (form)
  (let ((len (length form)))
    (cond ((= len 1)
	   (byte-compile-form ""))
	  ((= len 2)
	   ;; Concat of one arg is not a no-op if arg is not a string.
	   (byte-compile-normal-call form))
	  ((< len 6)
	   (let ((args (cdr form)))
	     (while args
	       (byte-compile-form (car args))
	       (setq args (cdr args)))
	     (setq byte-compile-depth (- byte-compile-depth (1- len)))
	     (byte-compile-out
	       (symbol-value (nth (- len 3)
				  '(byte-concat2 byte-concat3 byte-concat4)))
	       0)))
	  (t
	   (byte-compile-normal-call form)))))

(put '- 'byte-compile 'byte-compile-minus)
(defun byte-compile-minus (form)
  (let ((len (length form)))
    (cond ((= len 2)
	   (byte-compile-form (car (cdr form)))
	   (setq byte-compile-depth (- byte-compile-depth 1))
	   (byte-compile-out byte-negate 0))
	  ((= len 3)
	   (byte-compile-form (car (cdr form)))
	   (byte-compile-form (nth 2 form))
	   (setq byte-compile-depth (- byte-compile-depth 2))
	   (byte-compile-out byte-diff 0))
	  (t (byte-compile-normal-call form)))))

(put '+ 'byte-compile 'byte-compile-maybe-two-args)
(put '+ 'byte-opcode 'byte-plus)

(put 'max 'byte-compile 'byte-compile-maybe-two-args)
(put 'max 'byte-opcode 'byte-max)

(put 'min 'byte-compile 'byte-compile-maybe-two-args)
(put 'min 'byte-opcode 'byte-min)

(defun byte-compile-maybe-two-args (form)
  (let ((len (length form)))
    (if (= len 3)
	(progn
	  (byte-compile-form (car (cdr form)))
	  (byte-compile-form (nth 2 form))
	  (setq byte-compile-depth (- byte-compile-depth 2))
	  (byte-compile-out (symbol-value (get (car form) 'byte-opcode)) 0))
      (byte-compile-normal-call form))))
	
(defun byte-compile-normal-call (form)
  (byte-compile-push-constant (car form))
  (let ((copy (cdr form)))
    (while copy (byte-compile-form (car copy)) (setq copy (cdr copy))))
  (byte-compile-out 'byte-call (length (cdr form)))
  (setq byte-compile-depth (- byte-compile-depth (length (cdr form)))))

(put 'function 'byte-compile 'byte-compile-function-form)
(defun byte-compile-function-form (form)
  (byte-compile-constant (byte-compile-lambda (car (cdr form)))))

(put 'indent-to 'byte-compile 'byte-compile-indent-to)
(defun byte-compile-indent-to (form)
  (let ((len (length form)))
    (if (= len 2)
	(progn
	  (byte-compile-form (car (cdr form)))
	  (setq byte-compile-depth (- byte-compile-depth 1))
	  (byte-compile-out byte-indent-to 0))
      (byte-compile-normal-call form))))

(put 'insert 'byte-compile 'byte-compile-insert)
(defun byte-compile-insert (form)
  (let ((len (length form)))
    (if (< len 3)
	(let ((args (cdr form)))
	  (while args
	    (byte-compile-form (car args))
	    (setq byte-compile-depth (- byte-compile-depth 1))
	    (byte-compile-out byte-insert 0)
	    (setq args (cdr args))))
      (byte-compile-normal-call form))))

(put 'quote 'byte-compile 'byte-compile-quote)
(defun byte-compile-quote (form)
  (byte-compile-constant (car (cdr form))))

(put 'setq 'byte-compile 'byte-compile-setq)
(defun byte-compile-setq (form)
  (let ((args (cdr form)))
    (while args
      (byte-compile-form (car (cdr args)))
      (if (null (cdr (cdr args)))
	  (progn
	    (byte-compile-out 'byte-dup 0)
	    (setq byte-compile-maxdepth (max byte-compile-maxdepth (1+ byte-compile-depth)))))
      (setq byte-compile-depth (1- byte-compile-depth))
      (byte-compile-variable-ref 'byte-varset (car args))
      (setq args (cdr (cdr args))))))

(put 'let 'byte-compile 'byte-compile-let)
(defun byte-compile-let (form)
  (let ((varlist (car (cdr form))))
    (while varlist
      (if (symbolp (car varlist))
	  (byte-compile-push-constant nil)
	(byte-compile-form (car (cdr (car varlist)))))
      (setq varlist (cdr varlist))))
  (let ((varlist (reverse (car (cdr form)))))
    (setq byte-compile-depth (- byte-compile-depth (length varlist)))
    (while varlist
      (if (symbolp (car varlist))
	  (byte-compile-variable-ref 'byte-varbind (car varlist))
	(byte-compile-variable-ref 'byte-varbind (car (car varlist))))
      (setq varlist (cdr varlist))))
  (byte-compile-body (cdr (cdr form)))
  (byte-compile-out 'byte-unbind (length (car (cdr form)))))

(put 'let* 'byte-compile 'byte-compile-let*)
(defun byte-compile-let* (form)
  (let ((varlist (car (cdr form))))
    (while varlist
      (if (symbolp (car varlist))
	  (byte-compile-push-constant nil)
	(byte-compile-form (car (cdr (car varlist)))))
      (setq byte-compile-depth (1- byte-compile-depth))
      (if (symbolp (car varlist))
	  (byte-compile-variable-ref 'byte-varbind (car varlist))
	(byte-compile-variable-ref 'byte-varbind (car (car varlist))))
      (setq varlist (cdr varlist))))
  (byte-compile-body (cdr (cdr form)))
  (byte-compile-out 'byte-unbind (length (car (cdr form)))))

(put 'save-excursion 'byte-compile 'byte-compile-save-excursion)
(defun byte-compile-save-excursion (form)
  (byte-compile-out 'byte-save-excursion 0)
  (byte-compile-body (cdr form))
  (byte-compile-out 'byte-unbind 1))

(put 'save-restriction 'byte-compile 'byte-compile-save-restriction)
(defun byte-compile-save-restriction (form)
  (byte-compile-out 'byte-save-restriction 0)
  (byte-compile-body (cdr form))
  (byte-compile-out 'byte-unbind 1))

(put 'with-output-to-temp-buffer 'byte-compile 'byte-compile-with-output-to-temp-buffer)
(defun byte-compile-with-output-to-temp-buffer (form)
  (byte-compile-form (car (cdr form)))
  (byte-compile-out 'byte-temp-output-buffer-setup 0)
  (byte-compile-body (cdr (cdr form)))
  (byte-compile-out 'byte-temp-output-buffer-show 0)
  (setq byte-compile-depth (1- byte-compile-depth)))

(put 'progn 'byte-compile 'byte-compile-progn)
(defun byte-compile-progn (form)
  (byte-compile-body (cdr form)))

(put 'interactive 'byte-compile 'byte-compile-noop)
(defun byte-compile-noop (form)
  (byte-compile-constant nil))

(defun byte-compile-body (body)
  (if (null body)
      (byte-compile-constant nil)
    (while body
      (byte-compile-form (car body))
      (if (cdr body)
	  (byte-compile-discard)
	;; Convention is this will be counted after we return.
	(setq byte-compile-depth (1- byte-compile-depth)))
      (setq body (cdr body)))))

(put 'prog1 'byte-compile 'byte-compile-prog1)
(defun byte-compile-prog1 (form)
  (byte-compile-form (car (cdr form)))
  (if (cdr (cdr form))
      (progn
	(byte-compile-body (cdr (cdr form)))
	;; This discards the value pushed by ..-body
	;; (which is not counted now in byte-compile-depth)
	;; and decrements byte-compile-depth for the value
	;; pushed by byte-compile-form above, which by convention
	;; will be counted in byte-compile-depth after we return.
	(byte-compile-discard))))

(put 'prog2 'byte-compile 'byte-compile-prog2)
(defun byte-compile-prog2 (form)
  (byte-compile-form (car (cdr form)))
  (byte-compile-discard)
  (byte-compile-form (nth 2 form))
  (if (cdr (cdr (cdr form)))
      (progn
	(byte-compile-body (cdr (cdr (cdr form))))
	(byte-compile-discard))))

(defun byte-compile-discard ()
  (byte-compile-out 'byte-discard 0)
  (setq byte-compile-depth (1- byte-compile-depth)))

(put 'if 'byte-compile 'byte-compile-if)
(defun byte-compile-if (form)
  (if (null (cdr (cdr form)))
      ;; No else-forms
      (let ((donetag (byte-compile-make-tag)))
	(byte-compile-form (car (cdr form)))
	(byte-compile-goto 'byte-goto-if-nil-else-pop donetag)
	(setq byte-compile-depth (1- byte-compile-depth))
	(byte-compile-form (nth 2 form))
	(setq byte-compile-depth (1- byte-compile-depth))
	(byte-compile-out-tag donetag))
    (let ((donetag (byte-compile-make-tag)) (elsetag (byte-compile-make-tag)))
      (byte-compile-form (car (cdr form)))
      (byte-compile-goto 'byte-goto-if-nil elsetag)
      (setq byte-compile-depth (1- byte-compile-depth))
      (byte-compile-form (nth 2 form))
      (setq byte-compile-depth (1- byte-compile-depth))
      (byte-compile-goto 'byte-goto donetag)
      (byte-compile-out-tag elsetag)
      (byte-compile-body (cdr (cdr (cdr form))))
      (byte-compile-out-tag donetag))))

(put 'cond 'byte-compile 'byte-compile-cond)
(defun byte-compile-cond (form)
  (if (cdr form)
      (byte-compile-cond-1 (cdr form))))
(defun byte-compile-cond-1 (clauses)
  (if (null (cdr clauses))
      ;; Only one clause
      (let ((donetag (byte-compile-make-tag)))
	(byte-compile-form (car (car clauses)))
	(cond ((cdr (car clauses))
	       (byte-compile-goto 'byte-goto-if-nil-else-pop donetag)
	       (setq byte-compile-depth (1- byte-compile-depth))
	       (byte-compile-body (cdr (car clauses)))
	       (byte-compile-out-tag donetag))))
    (let ((donetag (byte-compile-make-tag))
	  (elsetag (byte-compile-make-tag)))
      (byte-compile-form (car (car clauses)))
      (byte-compile-goto 'byte-goto-if-nil elsetag)
      (setq byte-compile-depth (1- byte-compile-depth))
      (byte-compile-body (cdr (car clauses)))
      (byte-compile-goto 'byte-goto donetag)
      (byte-compile-out-tag elsetag)
      (byte-compile-cond-1 (cdr clauses))
      (byte-compile-out-tag donetag))))

(put 'and 'byte-compile 'byte-compile-and)
(defun byte-compile-and (form)
  (let ((failtag (byte-compile-make-tag))
	(args (cdr form)))
    (if (null args)
	(progn
	  (byte-compile-form t)
	  (setq byte-compile-depth (1- byte-compile-depth)))
      (while args
	(byte-compile-form (car args))
	(setq byte-compile-depth (1- byte-compile-depth))
	(if (null (cdr args))
	    (byte-compile-out-tag failtag)
	  (byte-compile-goto 'byte-goto-if-nil-else-pop failtag))
	(setq args (cdr args))))))

(put 'or 'byte-compile 'byte-compile-or)
(defun byte-compile-or (form)
  (let ((wintag (byte-compile-make-tag))
	(args (cdr form)))
    (if (null args)
	(byte-compile-constant nil)
      (while args
	(byte-compile-form (car args))
	(setq byte-compile-depth (1- byte-compile-depth))
	(if (null (cdr args))
	    (byte-compile-out-tag wintag)
	  (byte-compile-goto 'byte-goto-if-not-nil-else-pop wintag))
	(setq args (cdr args))))))

(put 'while 'byte-compile 'byte-compile-while)
(defun byte-compile-while (form)
  (let ((endtag (byte-compile-make-tag))
	(looptag (byte-compile-make-tag))
	(args (cdr (cdr form))))
    (byte-compile-out-tag looptag)
    (byte-compile-form (car (cdr form)))
    (byte-compile-goto 'byte-goto-if-nil-else-pop endtag)
    (byte-compile-body (cdr (cdr form)))
    (byte-compile-discard)
    (byte-compile-goto 'byte-goto looptag)
    (byte-compile-out-tag endtag)))

(put 'catch 'byte-compile 'byte-compile-catch)
(defun byte-compile-catch (form)
  (byte-compile-form (car (cdr form)))
  (byte-compile-push-constant (byte-compile-top-level (cons 'progn (cdr (cdr form)))))
  (setq byte-compile-depth (- byte-compile-depth 2))
  (byte-compile-out 'byte-catch 0))

(put 'save-window-excursion 'byte-compile 'byte-compile-save-window-excursion)
(defun byte-compile-save-window-excursion (form)
  (byte-compile-push-constant
    (list (byte-compile-top-level (cons 'progn (cdr form)))))
  (setq byte-compile-depth (1- byte-compile-depth))
  (byte-compile-out 'byte-save-window-excursion 0))

(put 'unwind-protect 'byte-compile 'byte-compile-unwind-protect)
(defun byte-compile-unwind-protect (form)
  (byte-compile-push-constant
    (list (byte-compile-top-level (cons 'progn (cdr (cdr form))))))
  (setq byte-compile-depth (1- byte-compile-depth))
  (byte-compile-out 'byte-unwind-protect 0)
  (byte-compile-form (car (cdr form)))
  (setq byte-compile-depth (1- byte-compile-depth))
  (byte-compile-out 'byte-unbind 1))

(put 'condition-case 'byte-compile 'byte-compile-condition-case)
(defun byte-compile-condition-case (form)
  (byte-compile-push-constant (car (cdr form)))
  (byte-compile-push-constant (byte-compile-top-level (nth 2 form)))
  (let ((clauses (cdr (cdr (cdr form))))
	compiled-clauses)
    (while clauses
      (let ((clause (car clauses)))
	(setq compiled-clauses
	      (cons (list (car clause)
			  (byte-compile-top-level (cons 'progn (cdr clause))))
		    compiled-clauses)))
      (setq clauses (cdr clauses)))
    (byte-compile-push-constant (nreverse compiled-clauses)))
  (setq byte-compile-depth (- byte-compile-depth 3))
  (byte-compile-out 'byte-condition-case 0))

(defun byte-compile-make-tag ()
  (cons nil nil))

(defun byte-compile-out-tag (tag)
  (let ((uses (car tag)))
    (setcar tag byte-compile-pc)
    (while uses
      (byte-compile-store-goto (car uses) byte-compile-pc)
      (setq uses (cdr uses)))))

(defun byte-compile-goto (opcode tag)
  (byte-compile-out opcode 0)
  (if (integerp (car tag))
      (byte-compile-store-goto byte-compile-pc (car tag))
    (setcar tag (cons byte-compile-pc (car tag))))
  (setq byte-compile-pc (+ byte-compile-pc 2)))

(defun byte-compile-store-goto (at-pc to-pc)
  (setq byte-compile-output
	(cons (cons at-pc (logand to-pc 255))
	      byte-compile-output))
  (setq byte-compile-output
	(cons (cons (1+ at-pc) (lsh to-pc -8))
	      byte-compile-output)))

(defun byte-compile-out (opcode offset)
  (setq opcode (eval opcode))
  (if (< offset 6)
      (byte-compile-out-1 (+ opcode offset))
    (if (< offset 256)
	(progn
	  (byte-compile-out-1 (+ opcode 6))
	  (byte-compile-out-1 offset))
      (byte-compile-out-1 (+ opcode 7))
      (byte-compile-out-1 (logand offset 255))
      (byte-compile-out-1 (lsh offset -8)))))

(defun byte-compile-out-const (offset)
  (if (< offset byte-constant-limit)
      (byte-compile-out-1 (+ byte-constant offset))
    (byte-compile-out-1 byte-constant2)
    (byte-compile-out-1 (logand offset 255))
    (byte-compile-out-1 (lsh offset -8))))

(defun byte-compile-out-1 (code)
  (setq byte-compile-output
	(cons (cons byte-compile-pc code)
	      byte-compile-output))
  (setq byte-compile-pc (1+ byte-compile-pc)))

;;; by crl@newton.purdue.edu
;;;  Only works noninteractively.
(defun batch-byte-compile ()
  "Runs byte-compile-file on the files remaining on the command line.
Must be used only with -batch, and kills emacs on completion.
Each file will be processed even if an error occurred previously.
For example, invoke \"emacs -batch -f batch-byte-compile $emacs/ ~/*.el\""
  ;; command-line-args is what is left of the command line (from startup.el)
  (if (not noninteractive)
      (error "batch-byte-compile is to be used only with -batch"))
  (let ((error nil))
    (while command-line-args
      (if (file-directory-p (expand-file-name (car command-line-args)))
	  (let ((files (directory-files (car command-line-args)))
		source)
	    (while files
	      (if (and (string-match ".el$" (car files))
		       (not (auto-save-file-name-p (car files)))
		       (setq source (expand-file-name (car files)
						      (car command-line-args)))
		       (file-exists-p (concat source "c"))
		       (file-newer-than-file-p source (concat source "c")))
		  (if (null (batch-byte-compile-file source))
		      (setq error t)))
	      (setq files (cdr files))))
	(if (null (batch-byte-compile-file (car command-line-args)))
	    (setq error t)))
      (setq command-line-args (cdr command-line-args)))
    (message "Done")
    (kill-emacs (if error 1 0))))

(defun batch-byte-compile-file (file)
  (condition-case err
      (progn (byte-compile-file file) t)
    (error
     (message (if (cdr err)
		  ">>Error occurred processing %s: %s (%s)"
		  ">>Error occurred processing %s: %s")
	      file
	      (get (car err) 'error-message)
	      (prin1-to-string (cdr err)))
     nil)))