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view src/alloca.s @ 5253:b6a398dbb403
Fewer algorithmic complexity surprises, nicer errors, mapcarX(), maplist()
src/ChangeLog addition:
2010-09-01 Aidan Kehoe <kehoea@parhasard.net>
* fns.c (list_merge, list_array_merge_into_list)
(list_array_merge_into_array):
Avoid algorithmic complexity surprises when checking for
circularity in these functions.
(Freduce): Fix some formatting, in passing.
(mapcarX): Drop the SOME_OR_EVERY argument to this function;
instead, take CALLER, a symbol reflecting the Lisp-visible
function that called mapcarX(). Use CALLER with
mapping_interaction_error() when sequences are modified
illegally. Don't cons with #'some, #'every, not even a little.
(Fmapconcat, FmapcarX, Fmapvector, Fmapcan, Fmapc, Fmap)
(Fmap_into, Fsome, Fevery): Call mapcarX() with its new
arguments.
(Fmapcan): Don't unnecessarily complicate the nconc call.
(maplist): Take CALLER, a symbol reflecting the Lisp-visible
function that called maplist(), rather than having separate
arguments to indicate mapl vs. mapcon.
Avoid algorithmic complexity surprises when checking for
circularity. In #'mapcon, check a given stretch of
result for well-formedness once, which was not previously the
case, despite what the comments said.
(Fmaplist, Fmapl, Fmapcon):
Call maplist() with its new arguments.
| author | Aidan Kehoe <kehoea@parhasard.net> |
|---|---|
| date | Wed, 01 Sep 2010 12:51:32 +0100 |
| parents | aa5ed11f473b |
| children | 308d34e9f07d |
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/* `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 */