[bpt/emacs.git] / lisp / emacs-lisp / disass.el

;;; disass.el --- disassembler for compiled Emacs Lisp code

;; Copyright (C) 1986, 1991, 2002-2014 Free Software Foundation, Inc.

;; Author: Doug Cutting <doug@csli.stanford.edu>
;;	Jamie Zawinski <jwz@lucid.com>
;; Maintainer: emacs-devel@gnu.org
;; Keywords: internal

;; This file is part of GNU Emacs.

;; GNU Emacs is free software: you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.

;; GNU Emacs is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;; GNU General Public License for more details.

;; You should have received a copy of the GNU General Public License
;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.

;;; Commentary:

;; The single entry point, `disassemble', disassembles a code object generated
;; by the Emacs Lisp byte-compiler.  This doesn't invert the compilation
;; operation, not by a long shot, but it's useful for debugging.

;;
;; Original version by Doug Cutting (doug@csli.stanford.edu)
;; Substantially modified by Jamie Zawinski <jwz@lucid.com> for
;; the new lapcode-based byte compiler.

;;; Code:

(require 'macroexp)

;;; The variable byte-code-vector is defined by the new bytecomp.el.
;;; The function byte-decompile-lapcode is defined in byte-opt.el.
;;; Since we don't use byte-decompile-lapcode, let's try not loading byte-opt.
(require 'byte-compile "bytecomp")

(defvar disassemble-column-1-indent 8 "*")
(defvar disassemble-column-2-indent 10 "*")

(defvar disassemble-recursive-indent 3 "*")

;;;###autoload
(defun disassemble (object &optional buffer indent interactive-p)
  "Print disassembled code for OBJECT in (optional) BUFFER.
OBJECT can be a symbol defined as a function, or a function itself
\(a lambda expression or a compiled-function object).
If OBJECT is not already compiled, we compile it, but do not
redefine OBJECT if it is a symbol."
  (interactive (list (intern (completing-read "Disassemble function: "
					      obarray 'fboundp t))
		     nil 0 t))
  (if (and (consp object) (not (eq (car object) 'lambda)))
      (setq object (list 'lambda () object)))
  (or indent (setq indent 0))		;Default indent to zero
  (save-excursion
    (if (or interactive-p (null buffer))
	(with-output-to-temp-buffer "*Disassemble*"
	  (set-buffer "*Disassemble*")
	  (disassemble-internal object indent (not interactive-p)))
      (set-buffer buffer)
      (disassemble-internal object indent nil)))
  nil)


(defun disassemble-internal (obj indent interactive-p)
  (let ((macro 'nil)
	(name 'nil)
	(doc 'nil)
	args)
    (while (symbolp obj)
      (setq name obj
	    obj (symbol-function obj)))
    (if (subrp obj)
	(error "Can't disassemble #<subr %s>" name))
    (setq obj (autoload-do-load obj name))
    (if (eq (car-safe obj) 'macro)	;Handle macros.
	(setq macro t
	      obj (cdr obj)))
    (if (and (listp obj) (eq (car obj) 'byte-code))
	(setq obj (list 'lambda nil obj)))
    (if (and (listp obj) (not (eq (car obj) 'lambda)))
	(error "not a function"))
    (if (consp obj)
	(if (assq 'byte-code obj)
	    nil
	  (if interactive-p (message (if name
					 "Compiling %s's definition..."
				       "Compiling definition...")
				     name))
	  (setq obj (byte-compile obj))
	  (if interactive-p (message "Done compiling.  Disassembling..."))))
    (cond ((consp obj)
	   (setq obj (cdr obj))		;throw lambda away
	   (setq args (car obj))	;save arg list
	   (setq obj (cdr obj)))
	  ((byte-code-function-p obj)
	   (setq args (aref obj 0)))
          (t (error "Compilation failed")))
    (if (zerop indent) ; not a nested function
	(progn
	  (indent-to indent)
	  (insert (format "byte code%s%s%s:\n"
			  (if (or macro name) " for" "")
			  (if macro " macro" "")
			  (if name (format " %s" name) "")))))
    (let ((doc (if (consp obj)
		   (and (stringp (car obj)) (car obj))
		 ;; Use documentation to get lazy-loaded doc string
		 (documentation obj t))))
      (if (and doc (stringp doc))
	  (progn (and (consp obj) (setq obj (cdr obj)))
		 (indent-to indent)
		 (princ "  doc:  " (current-buffer))
		 (if (string-match "\n" doc)
		     (setq doc (concat (substring doc 0 (match-beginning 0))
				       " ...")))
		 (insert doc "\n"))))
    (indent-to indent)
    (insert "  args: ")
    (prin1 args (current-buffer))
    (insert "\n")
    (let ((interactive (cond ((consp obj)
			      (assq 'interactive obj))
			     ((> (length obj) 5)
			      (list 'interactive (aref obj 5))))))
      (if interactive
	  (progn
	    (setq interactive (nth 1 interactive))
	    (if (eq (car-safe (car-safe obj)) 'interactive)
		(setq obj (cdr obj)))
	    (indent-to indent)
	    (insert " interactive: ")
	    (if (eq (car-safe interactive) 'byte-code)
		(progn
		  (insert "\n")
		  (disassemble-1 interactive
				 (+ indent disassemble-recursive-indent)))
	      (let ((print-escape-newlines t))
		(prin1 interactive (current-buffer))))
	    (insert "\n"))))
    (cond ((and (consp obj) (assq 'byte-code obj))
	   (disassemble-1 (assq 'byte-code obj) indent))
	  ((byte-code-function-p obj)
	   (disassemble-1 obj indent))
	  (t
	   (insert "Uncompiled body:  ")
	   (let ((print-escape-newlines t))
	     (prin1 (macroexp-progn obj)
		    (current-buffer))))))
  (if interactive-p
      (message "")))


(defun disassemble-1 (obj indent)
  "Prints the byte-code call OBJ in the current buffer.
OBJ should be a call to BYTE-CODE generated by the byte compiler."
  (let (bytes constvec)
    (if (consp obj)
	(setq bytes (car (cdr obj))		;the byte code
	      constvec (car (cdr (cdr obj))))	;constant vector
      ;; If it is lazy-loaded, load it now
      (fetch-bytecode obj)
      (setq bytes (aref obj 1)
	    constvec (aref obj 2)))
    (let ((lap (byte-decompile-bytecode (string-as-unibyte bytes) constvec))
	  op arg opname pc-value)
      (let ((tagno 0)
	    tmp
	    (lap lap))
	(while (setq tmp (assq 'TAG lap))
	  (setcar (cdr tmp) (setq tagno (1+ tagno)))
	  (setq lap (cdr (memq tmp lap)))))
      (while lap
	;; Take off the pc value of the next thing
	;; and put it in pc-value.
	(setq pc-value nil)
	(if (numberp (car lap))
	    (setq pc-value (car lap)
		  lap (cdr lap)))
	;; Fetch the next op and its arg.
	(setq op (car (car lap))
	      arg (cdr (car lap)))
	(setq lap (cdr lap))
	(indent-to indent)
	(if (eq 'TAG op)
	    (progn
	      ;; We have a label.  Display it, but first its pc value.
	      (if pc-value
		  (insert (format "%d:" pc-value)))
	      (insert (int-to-string (car arg))))
	  ;; We have an instruction.  Display its pc value first.
	  (if pc-value
	      (insert (format "%d" pc-value)))
	  (indent-to (+ indent disassemble-column-1-indent))
	  (if (and op
		   (string-match "^byte-" (setq opname (symbol-name op))))
	      (setq opname (substring opname 5))
	    (setq opname "<not-an-opcode>"))
	  (if (eq op 'byte-constant2)
	      (insert " #### shouldn't have seen constant2 here!\n  "))
	  (insert opname)
	  (indent-to (+ indent disassemble-column-1-indent
			disassemble-column-2-indent
			-1))
	  (insert " ")
	  (cond ((memq op byte-goto-ops)
		 (insert (int-to-string (nth 1 arg))))
		((memq op '(byte-call byte-unbind
			    byte-listN byte-concatN byte-insertN
			    byte-stack-ref byte-stack-set byte-stack-set2
			    byte-discardN byte-discardN-preserve-tos))
		 (insert (int-to-string arg)))
		((memq op '(byte-varref byte-varset byte-varbind))
		 (prin1 (car arg) (current-buffer)))
		((memq op '(byte-constant byte-constant2))
		 ;; it's a constant
		 (setq arg (car arg))
		 ;; but if the value of the constant is compiled code, then
		 ;; recursively disassemble it.
		 (cond ((or (byte-code-function-p arg)
			    (and (eq (car-safe arg) 'lambda)
				 (assq 'byte-code arg))
			    (and (eq (car-safe arg) 'macro)
				 (or (byte-code-function-p (cdr arg))
				     (and (eq (car-safe (cdr arg)) 'lambda)
					  (assq 'byte-code (cdr arg))))))
			(cond ((byte-code-function-p arg)
			       (insert "<compiled-function>\n"))
			      ((eq (car-safe arg) 'lambda)
			       (insert "<compiled lambda>"))
			      (t (insert "<compiled macro>\n")))
			(disassemble-internal
			 arg
			 (+ indent disassemble-recursive-indent 1)
			 nil))
		       ((eq (car-safe arg) 'byte-code)
			(insert "<byte code>\n")
			(disassemble-1	;recurse on byte-code object
			 arg
			 (+ indent disassemble-recursive-indent)))
		       ((eq (car-safe (car-safe arg)) 'byte-code)
			(insert "(<byte code>...)\n")
			(mapc ;recurse on list of byte-code objects
			 (lambda (obj)
                           (disassemble-1
                            obj
                            (+ indent disassemble-recursive-indent)))
			 arg))
		       (t
			;; really just a constant
			(let ((print-escape-newlines t))
			  (prin1 arg (current-buffer))))))
		)
	  (insert "\n")))))
  nil)

(provide 'disass)

;;; disass.el ends here
Commit	Line	Data
fd7fa35a ER	1	;;; disass.el --- disassembler for compiled Emacs Lisp code
fd7fa35a ER	2
ba318903	3	;; Copyright (C) 1986, 1991, 2002-2014 Free Software Foundation, Inc.
9750e079	4
fd7fa35a ER	5	;; Author: Doug Cutting <doug@csli.stanford.edu>
fd7fa35a ER	6	;; Jamie Zawinski <jwz@lucid.com>
34dc21db	7	;; Maintainer: emacs-devel@gnu.org
e9571d2a	8	;; Keywords: internal
fd7fa35a	9
1c393159 JB	10	;; This file is part of GNU Emacs.
1c393159 JB	11
d6cba7ae	12	;; GNU Emacs is free software: you can redistribute it and/or modify
1c393159	13	;; it under the terms of the GNU General Public License as published by
d6cba7ae GM	14	;; the Free Software Foundation, either version 3 of the License, or
d6cba7ae GM	15	;; (at your option) any later version.
1c393159 JB	16
	17	;; GNU Emacs is distributed in the hope that it will be useful,
	18	;; but WITHOUT ANY WARRANTY; without even the implied warranty of
	19	;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	20	;; GNU General Public License for more details.
	21
	22	;; You should have received a copy of the GNU General Public License
d6cba7ae	23	;; along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>.
1c393159	24
fd7fa35a ER	25	;;; Commentary:
fd7fa35a ER	26
e41b2db1 ER	27	;; The single entry point, `disassemble', disassembles a code object generated
	28	;; by the Emacs Lisp byte-compiler. This doesn't invert the compilation
	29	;; operation, not by a long shot, but it's useful for debugging.
	30
	31	;;
	32	;; Original version by Doug Cutting (doug@csli.stanford.edu)
	33	;; Substantially modified by Jamie Zawinski <jwz@lucid.com> for
	34	;; the new lapcode-based byte compiler.
fd7fa35a ER	35
fd7fa35a ER	36	;;; Code:
1c393159	37
4dd1c416 SM	38	(require 'macroexp)
4dd1c416 SM	39
1c393159	40	;;; The variable byte-code-vector is defined by the new bytecomp.el.
c29118da JB	41	;;; The function byte-decompile-lapcode is defined in byte-opt.el.
c29118da JB	42	;;; Since we don't use byte-decompile-lapcode, let's try not loading byte-opt.
d28a1925	43	(require 'byte-compile "bytecomp")
1c393159	44
3c7e6b9d	45	(defvar disassemble-column-1-indent 8 "*")
1c393159 JB	46	(defvar disassemble-column-2-indent 10 "*")
	47
	48	(defvar disassemble-recursive-indent 3 "*")
	49
dbc4e1c1	50	;;;###autoload
1c393159 JB	51	(defun disassemble (object &optional buffer indent interactive-p)
	52	"Print disassembled code for OBJECT in (optional) BUFFER.
	53	OBJECT can be a symbol defined as a function, or a function itself
	54	\(a lambda expression or a compiled-function object).
	55	If OBJECT is not already compiled, we compile it, but do not
	56	redefine OBJECT if it is a symbol."
	57	(interactive (list (intern (completing-read "Disassemble function: "
	58	obarray 'fboundp t))
	59	nil 0 t))
dc0485c4	60	(if (and (consp object) (not (eq (car object) 'lambda)))
1c393159 JB	61	(setq object (list 'lambda () object)))
	62	(or indent (setq indent 0)) ;Default indent to zero
	63	(save-excursion
	64	(if (or interactive-p (null buffer))
	65	(with-output-to-temp-buffer "Disassemble"
	66	(set-buffer "Disassemble")
	67	(disassemble-internal object indent (not interactive-p)))
	68	(set-buffer buffer)
	69	(disassemble-internal object indent nil)))
	70	nil)
	71
	72
	73	(defun disassemble-internal (obj indent interactive-p)
	74	(let ((macro 'nil)
	75	(name 'nil)
	76	(doc 'nil)
	77	args)
	78	(while (symbolp obj)
	79	(setq name obj
	80	obj (symbol-function obj)))
	81	(if (subrp obj)
	82	(error "Can't disassemble #<subr %s>" name))
7abaf5cc SM	83	(setq obj (autoload-do-load obj name))
7abaf5cc SM	84	(if (eq (car-safe obj) 'macro) ;Handle macros.
1c393159 JB	85	(setq macro t
1c393159 JB	86	obj (cdr obj)))
8dff74b7	87	(if (and (listp obj) (eq (car obj) 'byte-code))
a1506d29	88	(setq obj (list 'lambda nil obj)))
1c393159 JB	89	(if (and (listp obj) (not (eq (car obj) 'lambda)))
	90	(error "not a function"))
	91	(if (consp obj)
	92	(if (assq 'byte-code obj)
	93	nil
	94	(if interactive-p (message (if name
	95	"Compiling %s's definition..."
	96	"Compiling definition...")
	97	name))
	98	(setq obj (byte-compile obj))
	99	(if interactive-p (message "Done compiling. Disassembling..."))))
	100	(cond ((consp obj)
	101	(setq obj (cdr obj)) ;throw lambda away
	102	(setq args (car obj)) ;save arg list
	103	(setq obj (cdr obj)))
c757fb07 RS	104	((byte-code-function-p obj)
	105	(setq args (aref obj 0)))
	106	(t (error "Compilation failed")))
1c393159 JB	107	(if (zerop indent) ; not a nested function
	108	(progn
	109	(indent-to indent)
	110	(insert (format "byte code%s%s%s:\n"
	111	(if (or macro name) " for" "")
	112	(if macro " macro" "")
	113	(if name (format " %s" name) "")))))
	114	(let ((doc (if (consp obj)
	115	(and (stringp (car obj)) (car obj))
3fd4909e RS	116	;; Use documentation to get lazy-loaded doc string
3fd4909e RS	117	(documentation obj t))))
1c393159 JB	118	(if (and doc (stringp doc))
	119	(progn (and (consp obj) (setq obj (cdr obj)))
	120	(indent-to indent)
	121	(princ " doc: " (current-buffer))
	122	(if (string-match "\n" doc)
	123	(setq doc (concat (substring doc 0 (match-beginning 0))
	124	" ...")))
	125	(insert doc "\n"))))
	126	(indent-to indent)
	127	(insert " args: ")
	128	(prin1 args (current-buffer))
	129	(insert "\n")
	130	(let ((interactive (cond ((consp obj)
	131	(assq 'interactive obj))
	132	((> (length obj) 5)
	133	(list 'interactive (aref obj 5))))))
	134	(if interactive
	135	(progn
	136	(setq interactive (nth 1 interactive))
	137	(if (eq (car-safe (car-safe obj)) 'interactive)
	138	(setq obj (cdr obj)))
	139	(indent-to indent)
	140	(insert " interactive: ")
	141	(if (eq (car-safe interactive) 'byte-code)
	142	(progn
	143	(insert "\n")
	144	(disassemble-1 interactive
	145	(+ indent disassemble-recursive-indent)))
	146	(let ((print-escape-newlines t))
	147	(prin1 interactive (current-buffer))))
	148	(insert "\n"))))
	149	(cond ((and (consp obj) (assq 'byte-code obj))
	150	(disassemble-1 (assq 'byte-code obj) indent))
dbc4e1c1	151	((byte-code-function-p obj)
1c393159 JB	152	(disassemble-1 obj indent))
	153	(t
	154	(insert "Uncompiled body: ")
	155	(let ((print-escape-newlines t))
4dd1c416	156	(prin1 (macroexp-progn obj)
1c393159 JB	157	(current-buffer))))))
	158	(if interactive-p
	159	(message "")))
	160
	161
	162	(defun disassemble-1 (obj indent)
	163	"Prints the byte-code call OBJ in the current buffer.
	164	OBJ should be a call to BYTE-CODE generated by the byte compiler."
	165	(let (bytes constvec)
	166	(if (consp obj)
	167	(setq bytes (car (cdr obj)) ;the byte code
	168	constvec (car (cdr (cdr obj)))) ;constant vector
3fd4909e RS	169	;; If it is lazy-loaded, load it now
3fd4909e RS	170	(fetch-bytecode obj)
d18a808f	171	(setq bytes (aref obj 1)
1c393159	172	constvec (aref obj 2)))
d18a808f	173	(let ((lap (byte-decompile-bytecode (string-as-unibyte bytes) constvec))
3c7e6b9d	174	op arg opname pc-value)
1c393159 JB	175	(let ((tagno 0)
	176	tmp
	177	(lap lap))
	178	(while (setq tmp (assq 'TAG lap))
	179	(setcar (cdr tmp) (setq tagno (1+ tagno)))
	180	(setq lap (cdr (memq tmp lap)))))
	181	(while lap
3c7e6b9d RS	182	;; Take off the pc value of the next thing
	183	;; and put it in pc-value.
	184	(setq pc-value nil)
	185	(if (numberp (car lap))
	186	(setq pc-value (car lap)
	187	lap (cdr lap)))
	188	;; Fetch the next op and its arg.
1c393159 JB	189	(setq op (car (car lap))
1c393159 JB	190	arg (cdr (car lap)))
3c7e6b9d	191	(setq lap (cdr lap))
1c393159 JB	192	(indent-to indent)
1c393159 JB	193	(if (eq 'TAG op)
3c7e6b9d RS	194	(progn
	195	;; We have a label. Display it, but first its pc value.
	196	(if pc-value
	197	(insert (format "%d:" pc-value)))
	198	(insert (int-to-string (car arg))))
	199	;; We have an instruction. Display its pc value first.
	200	(if pc-value
	201	(insert (format "%d" pc-value)))
1c393159 JB	202	(indent-to (+ indent disassemble-column-1-indent))
	203	(if (and op
	204	(string-match "^byte-" (setq opname (symbol-name op))))
	205	(setq opname (substring opname 5))
	206	(setq opname "<not-an-opcode>"))
	207	(if (eq op 'byte-constant2)
	208	(insert " #### shouldn't have seen constant2 here!\n "))
	209	(insert opname)
	210	(indent-to (+ indent disassemble-column-1-indent
	211	disassemble-column-2-indent
	212	-1))
	213	(insert " ")
	214	(cond ((memq op byte-goto-ops)
	215	(insert (int-to-string (nth 1 arg))))
	216	((memq op '(byte-call byte-unbind
b9598260 SM	217	byte-listN byte-concatN byte-insertN
	218	byte-stack-ref byte-stack-set byte-stack-set2
	219	byte-discardN byte-discardN-preserve-tos))
1c393159 JB	220	(insert (int-to-string arg)))
	221	((memq op '(byte-varref byte-varset byte-varbind))
	222	(prin1 (car arg) (current-buffer)))
	223	((memq op '(byte-constant byte-constant2))
	224	;; it's a constant
	225	(setq arg (car arg))
	226	;; but if the value of the constant is compiled code, then
	227	;; recursively disassemble it.
dbc4e1c1	228	(cond ((or (byte-code-function-p arg)
1c393159 JB	229	(and (eq (car-safe arg) 'lambda)
	230	(assq 'byte-code arg))
	231	(and (eq (car-safe arg) 'macro)
dbc4e1c1	232	(or (byte-code-function-p (cdr arg))
1c393159 JB	233	(and (eq (car-safe (cdr arg)) 'lambda)
1c393159 JB	234	(assq 'byte-code (cdr arg))))))
dbc4e1c1	235	(cond ((byte-code-function-p arg)
1c393159 JB	236	(insert "<compiled-function>\n"))
	237	((eq (car-safe arg) 'lambda)
	238	(insert "<compiled lambda>"))
	239	(t (insert "<compiled macro>\n")))
	240	(disassemble-internal
	241	arg
	242	(+ indent disassemble-recursive-indent 1)
	243	nil))
	244	((eq (car-safe arg) 'byte-code)
	245	(insert "<byte code>\n")
	246	(disassemble-1 ;recurse on byte-code object
	247	arg
	248	(+ indent disassemble-recursive-indent)))
	249	((eq (car-safe (car-safe arg)) 'byte-code)
	250	(insert "(<byte code>...)\n")
56a1431a	251	(mapc ;recurse on list of byte-code objects
4f91a816 SM	252	(lambda (obj)
	253	(disassemble-1
	254	obj
	255	(+ indent disassemble-recursive-indent)))
1c393159 JB	256	arg))
	257	(t
	258	;; really just a constant
	259	(let ((print-escape-newlines t))
	260	(prin1 arg (current-buffer))))))
	261	)
3c7e6b9d	262	(insert "\n")))))
1c393159	263	nil)
fd7fa35a	264
896546cd RS	265	(provide 'disass)
896546cd RS	266
fd7fa35a	267	;;; disass.el ends here