crt0.s

来自「抢占」· S 代码 · 共 61 行

;
;	C program assembly startup for an embedded environment.
;	-------------------------------------------------------
;
;	Written by Tomas Evensen 1993-04-17.
;	Copyright 1993 Diab Data AB.
;
;       Modified by Dave McCartney May 1996
;
	PSECT
	XDEF	START
	XREF	_clean1
	XREF	_size

START:
;
; insert/modify code here to initialize (if necessary):
; - sp (stack pointer)
; - a5 (data pointer)
; - the cache
; - exception vectors
;
; initialize sp to value from link editor command file
;	move.l	#___SP_INIT,a7
	move.l	#STKTOP,a7

; initialize a5 to sdata (provided by linker)
	move.l	#sdata,a5
;
; initialise the bss section to zero

	MOVE.L	#_clean1,A1
	MOVE.L	#_size,D1
	LSR.L	#2,D1
LOOP	CLR.L	(A1)+
	SUBQ.L	#1,D1
	BNE	LOOP
 

	
	jsr	_main	; go to main code


	section	.init,2,C
	XDEF	___init
___init:

	section	.fini,2,C
; Return from __init
	rts
	XDEF	___fini
___fini:

	section	.eini,2,C
; Return from ___fini



	rts		; this return will be used instead of illegal
                        ; if a benchmark driver routine is used