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cleanups to debug-print, try harder to make it work during GC -------------------- ChangeLog entries follow: -------------------- src/ChangeLog addition: 2010-02-08 Ben Wing <ben@xemacs.org> * emacs.c: * emacs.c (assert_failed): Fix comments about when inhibit_non_essential_printing_operations is set and how used. Increment/decrement in assert_failed rather than just setting/resetting to avoid hosing things in case we're called when the value is already non-zero. Similarly increment/ decrement in_assert_failed. * gc.c (gc_prepare): * gc.c (gc_finish): Increment/decrement inhibit_non_essential_printing_operations rather than setting/resetting. * print.c: * print.c (debug_out): * print.c (write_string_to_alternate_debugging_output): * print.c (restore_inhibit_non_essential_conversion_operations): * print.c (debug_print_exit): * print.c (debug_print_enter): * print.c (debug_prin1): * print.c (debug_p4): * print.c (ext_print_begin): * print.c (ext_print_end): * print.c (external_debug_print): * print.c (debug_p3): * print.c (debug_backtrace): * print.c (debug_short_backtrace): * print.c (vars_of_print): Lots of cleanup. Fix debug_out() so it binds inhibit_non_essential_printing_operations around it to ensure no conversion. Remove many other places that set the same var since the lower-level functions now all do it. A few other places, add inhibit_non_essential_printing_operations bindings.Extract the code out that sets up and resets lots of bindings in debug_prin1() so that debug_backtrace() can use it, and rewrite it to use the new STORE_VOID_IN_LISP() rather than having to have a single static opaque structure holding all the bindings (and not handling reentrancy). Fix raw `char' to be `CIbyte' in the declaration of `alternate_do_string'. * signal.c (check_what_happened): Fix bug: Don't try to check for QUIT when inhibit_non_essential_printing_operations or we may screw things up if QUIT happens during debug printing.
author Ben Wing <ben@xemacs.org>
date Mon, 08 Feb 2010 07:00:24 -0600
parents aa5ed11f473b
children 308d34e9f07d
line wrap: on
line source

/* `alloca' standard 4.2 subroutine for 68000's and 16000's and others.
   Copyright (C) 1985, 1986, 1988 Free Software Foundation, Inc.

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 19.30. */

/* Both 68000 systems I have run this on have had broken versions of alloca.
   Also, I am told that non-berkeley systems do not have it at all.
   So replace whatever system-provided alloca there may be
   on all 68000 systems.  */

#define NOT_C_CODE
#ifdef emacs
#include <config.h>
#else
#include "config.h"
#endif

#ifndef HAVE_ALLOCA  /* define this to use system's alloca */

#ifndef m68k
#ifndef m68000
you
lose!!
#endif /* m68000 */
#endif /* m68k */


#ifdef m68k			/* SGS assembler totally different */
	file	"alloca.s"
	global	alloca
alloca:
	mov.l	(%sp)+,%a1	# pop return addr from top of stack
	mov.l	(%sp)+,%d0	# pop size in bytes from top of stack
	add.l	&R%1,%d0	# round size up to long word
	and.l	&-4,%d0		# mask out lower two bits of size
	sub.l	%d0,%sp		# allocate by moving stack pointer
	tst.b	P%1(%sp)	# stack probe to allocate pages
	mov.l	%sp,%a0		# return pointer as pointer
	mov.l	%sp,%d0		# return pointer as int to avoid disaster
	add.l	&-4,%sp		# new top of stack
	jmp	(%a1)		# not a normal return
	set	S%1,64		# safety factor for C compiler scratch
	set	R%1,3+S%1	# add to size for rounding
	set	P%1,-132	# probe this far below current top of stack

#else /* not m68k */

#ifdef m68000

/* Some systems want the _, some do not.  Win with both kinds.  */
.globl	_alloca
_alloca:
.globl	alloca
alloca:
	movl	sp@+,a0
	movl	a7,d0
	subl	sp@,d0
	andl	#~3,d0
	movl	d0,sp
	tstb	sp@(0)		/* Make stack pages exist  */
				/* Needed on certain systems
				   that lack true demand paging */
	addql	#4,d0
	jmp	a0@

#endif /* m68000 */
#endif /* not m68k */

#endif /* not HAVE_ALLOCA */