--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/lisp/disass.el	Mon Aug 13 10:04:58 2007 +0200
@@ -0,0 +1,272 @@
+;;; disass.el --- disassembler for compiled Emacs Lisp code
+
+;;; Copyright (C) 1986, 1991-1994 Free Software Foundation, Inc.
+
+;; Author: Doug Cutting <doug@csli.stanford.edu>
+;;	Jamie Zawinski <jwz@netscape.com>
+;; Maintainer: Jamie Zawinski <jwz@netscape.com>
+;; Keywords: internal
+
+;; This file is part of XEmacs.
+
+;; XEmacs 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 2, or (at your option)
+;; any later version.
+
+;; XEmacs 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 XEmacs; see the file COPYING.  If not, write to the 
+;; Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+;; Boston, MA 02111-1307, USA.
+
+;;; Synched up with: FSF 19.28.
+
+;;; 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 for
+;; the new lapcode-based byte compiler.
+
+;;; Code:
+
+;;; 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.
+;;; The variable byte-code-vector is defined by the new bytecomp.el.
+;;; The function byte-decompile-lapcode is defined in byte-optimize.el.
+(require 'byte-optimize)
+
+(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 (eq (car-safe object) 'byte-code)
+      (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)
+	args)
+    (while (symbolp obj)
+      (setq name obj
+	    obj (symbol-function obj)))
+    (if (subrp obj)
+	(error "Can't disassemble #<subr %s>" name))
+    (if (eq (car-safe obj) 'autoload)
+	(progn
+	  (load (elt obj 1))
+	  (setq obj (symbol-function 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)))
+	  (t
+	   (setq args (compiled-function-arglist obj))))
+    (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))
+		 (condition-case error
+		     (documentation obj)
+		   (error (format "%S" error))))))
+      (if (and doc (stringp doc))
+	  (progn (and (consp obj) (setq obj (cdr obj)))
+		 (indent-to indent)
+		 (princ "  doc:  " (current-buffer))
+		 (let ((frobbed nil))
+		   (if (string-match "\n" doc)
+		       (setq doc (substring doc 0 (match-beginning 0))
+			     frobbed t))
+		   (if (> (length doc) 70)
+		       (setq doc (substring doc 0 65) frobbed t))
+		   (if frobbed (setq doc (concat doc " ..."))))
+		 (insert doc "\n"))))
+    (indent-to indent)
+    (insert "  args: ")
+    (prin1 args (current-buffer))
+    (insert "\n")
+    (if (condition-case ()
+	    (commandp obj)                  ; ie interactivep
+	  (error nil))
+	(let ((interactive (if (consp obj)
+			       (elt (assq 'interactive obj) 1)
+			     (elt (compiled-function-interactive obj) 1))))
+          (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))
+	  ((compiled-function-p obj)
+	   (disassemble-1 obj indent))
+	  (t
+	   (insert "Uncompiled body:  ")
+	   (let ((print-escape-newlines t))
+	     (prin1 (if (cdr obj) (cons 'progn obj) (car obj))
+		    (current-buffer))))))
+  (if interactive-p
+      (message nil)))
+
+
+(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
+      (setq bytes (compiled-function-instructions obj)
+	    constvec (compiled-function-constants obj)))
+    (let ((lap (byte-decompile-bytecode 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))
+		 (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 (compiled-function-p arg)
+			    (and (eq (car-safe arg) 'lambda)
+				 (assq 'byte-code arg))
+			    (and (eq (car-safe arg) 'macro)
+				 (or (compiled-function-p (cdr arg))
+				     (and (eq (car-safe (cdr arg)) 'lambda)
+					  (assq 'byte-code (cdr arg))))))
+			(cond ((compiled-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")
+			(mapcar		;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