Mercurial > hg > xemacs-beta

view src/alloca.s @ 5219:2d0937dc83cf

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Tidying of CL files; make docstrings read better, remove commented-out code 2010-05-30 Aidan Kehoe <kehoea@parhasard.net> * cl.el: Remove extraneous empty lines. Remove the commented-out Lisp implementation of #'last, #'copy-list. Remove #'cl-maclisp-member. (acons, pairlis): Have the argument list reflect the docstring for these functions. * cl-macs.el (defun*): Have the argument list reflect the docstring. Document the syntax of keywords in ARGLIST. (defmacro*): Have the argument list reflect the docstring. Document &body, &whole and &environment. (function*): Have the argument list reflect the docstring. (loop): Have the argument list reflect the docstring. (eval-when, dolist, dotimes, do-symbols, flet, labels, macrolet, symbol-macrolet): Specify the argument list using the arguments: (...) syntax. (define-setf-method, rotatef, defsubst*): Have the argument list reflect the docstring. (letf, letf*): Specify the argument list using the arguments: (...) syntax. (svref, acons, pairlis): Add compiler macros for these functions. * cl-extra.el: Remove the commented-out Lisp implementation of #'equalp. If we want to look at it, it's in version control. (cl-expt): Remove this. The subr #'expt is always available. Call #'cl-float-limits at dump time. Remove the commented-out Lisp implementation of #'subseq. (concatenate): Use (error 'invalid-argument ...) here, if TYPE is not understood. (list-length): Don't manually get the length of a list, call #'length and return nil if the list is circular. * byte-optimize.el (equalp): This needs byte-optimize-binary-predicate as its optimizer, as do the other equality predicates.
author Aidan Kehoe <kehoea@parhasard.net>
date Sun, 30 May 2010 13:27:36 +0100
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 */