crtxstack.asm

sdcc是为51等小型嵌入式cpu设计的c语言编译器支持数种不同类型的cpu

; /*-------------------------------------------------------------------------
; 
;   crtxstack.asm :- C run-time: setup xstack
; 
;    This library is free software; you can redistribute it and/or modify it
;    under the terms of the GNU Library General Public License as published by the
;    Free Software Foundation; either version 2, or (at your option) any
;    later version.
;    
;    This library 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 Library General Public License for more details.
;    
;    You should have received a copy of the GNU Library General Public License
;    along with this program; if not, write to the Free Software
;    Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
;    
;    In other words, you are welcome to use, share and improve this program.
;    You are forbidden to forbid anyone else to use, share and improve
;    what you give them.   Help stamp out software-hoarding!  
; -------------------------------------------------------------------------*/

	.area CSEG    (CODE)
	.area GSINIT0 (CODE)
	.area GSINIT1 (CODE)
	.area GSINIT2 (CODE)
	.area GSINIT3 (CODE)
	.area GSINIT4 (CODE)
	.area GSINIT5 (CODE)
	.area GSINIT  (CODE)
	.area GSFINAL (CODE)

	.globl __start__xstack
	.globl __XPAGE

	.area GSINIT1 (CODE)

__sdcc_init_xstack::

; Need to initialize in GSINIT1 in case the user's __sdcc_external_startup
; uses the xstack.
	
	mov	__XPAGE,#(__start__xstack >> 8)
	mov	_spx,#__start__xstack

	.area GSINIT5 (CODE)

; Need to initialize in GSINIT5 because __mcs51_genXINIT modifies __XPAGE
; and __mcs51_genRAMCLEAR modifies _spx.
	
	mov	__XPAGE,#(__start__xstack >> 8)
	mov	_spx,#__start__xstack