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Co-operate with the byte-optimizer in the bytecomp.el labels implementation. lisp/ChangeLog addition: 2012-05-05 Aidan Kehoe <kehoea@parhasard.net> Co-operate with the byte-optimizer in the bytecomp.el labels implementation, don't work against it. * byte-optimize.el: * byte-optimize.el (byte-compile-inline-expand): Call #'byte-compile-unfold-lambda explicitly here, don't assume that the byte-optimizer will do it. * byte-optimize.el (byte-compile-unfold-lambda): Call #'byte-optimize-body on the body, don't just mapcar #'byte-optimize-form along it. * byte-optimize.el (byte-optimize-lambda): New. Optimize a lambda form. * byte-optimize.el (byte-optimize-form-code-walker): Descend lambda expressions, defun, and defmacro, relevant for lexically-oriented operators like #'labels. * byte-optimize.el (byte-optimize-body): Only return a non-eq object if we've actually optimized something * bytecomp.el (byte-compile-initial-macro-environment): In the labels implementation, work with the byte optimizer, not against it; warn when labels are defined but not used, automatically inline labels that are used only once. * bytecomp.el (byte-recompile-directory): No need to wrap #'byte-compile-report-error in a lambda with #'call-with-condition-handler here. * bytecomp.el (byte-compile-form): Don't inline compiled-function objects, they're probably labels. * bytecomp.el (byte-compile-funcall): No longer inline lambdas, trust the byte optimizer to have done it properly, even for labels. * cl-extra.el (cl-macroexpand-all): Treat labels established by the byte compiler distinctly from those established by cl-macs.el. * cl-macs.el (cl-do-proclaim): Treat labels established by the byte compiler distinctly from those established by cl-macs.el. * gui.el (make-gui-button): When referring to the #'gui-button-action label, quote it using function, otherwise there's a warning from the byte compiler.
author Aidan Kehoe <kehoea@parhasard.net>
date Sat, 05 May 2012 20:48:24 +0100
parents 3889ef128488
children
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2002-07-17  Marcus Crestani  <crestani@informatik.uni-tuebingen.de>
	    Markus Kaltenbach  <makalten@informatik.uni-tuebingen.de>
	    Mike Sperber <mike@xemacs.org>

	updated 2003-07-29

	New KKCC-GC mark algorithm:
	configure flag : --use-kkcc

	For better understanding, first a few words about the mark algorithm 
	up to now:
	Every Lisp_Object has its own mark method, which calls mark_object
	with the stuff to be marked.
	Also, many Lisp_Objects have pdump descriptions memory_descriptions, 
	which are used by the portable dumper. The dumper gets all the 
	information it needs about the Lisp_Object from the descriptions.

	Also the garbage collector can use the information in the pdump
	descriptions, so we can get rid of the mark methods.
	That is what we have been doing.

	
	DUMPABLE FLAG
	-------------
	First we added a dumpable flag to lrecord_implementation. It shows,
	if the object is dumpable and should be processed by the dumper.
	The dumpable flag is the third argument of a lrecord_implementation
	definition (DEFINE_LRECORD_IMPLEMENTATION).
	If it is set to 1, the dumper processes the descriptions and dumps
	the Object, if it is set to 0, the dumper does not care about it.
		

	KKCC MARKING
	------------
	All Lisp_Objects have memory_descriptions now, so we could get
	rid of the mark_object calls.
	The KKCC algorithm manages its own stack. Instead of calling 
	mark_object, all the alive Lisp_Objects are pushed on the 
	kkcc_gc_stack. Then these elements on the stack  are processed 
	according to their descriptions.


	TODO
	----
	- For weakness use weak datatypes instead of XD_FLAG_NO_KKCC.
	  XD_FLAG_NO_KKCC occurs in:
		* elhash.c: htentry
		* extents.c: lispobject_gap_array, extent_list, extent_info
		* marker.c: marker     
	  Not everything has to be rewritten. See Ben's comment in lrecord.h.
	- Clean up special case marking (weak_hash_tables, weak_lists,
	  ephemerons).
	- Stack optimization (have one stack during runtime instead of 
	  malloc/free it for every garbage collect)

	There are a few Lisp_Objects, where there occurred differences and
	inexactness between the mark-method and the pdump description.  All
	these Lisp_Objects get dumped (except image instances), so their
	descriptions have been written, before we started our work:
	* alloc.c: string
	description: size_, data_, and plist is described
	mark: only plist is marked, but flush_cached_extent_info is called.
	      flush_cached_extent_info ->
		free_soe ->
		  free_extent_list ->
		    free_gap_array ->
		      gap_array_delete_all_markers ->
			Add gap_array to the gap_array_marker_freelist

	* glyphs.c: image_instance
	description: device is not set to nil
	mark: mark method sets device to nil if dead
	See comment above the description.