[unix-history] / usr / src / libc / sys / crt0.s

# C runtime startoff

	.set	exit,1
.globl	_exit
.globl	start
.globl	_main
.globl	_environ

#
#	C language startup routine

start:
	.word	0x0000
	subl2	$8,sp
	movl	8(sp),(sp)  #  argc
	movab	12(sp),r0
	movl	r0,4(sp)  #  argv
L1:
	tstl	(r0)+  #  null args term ?
	bneq	L1
	cmpl	r0,*4(sp)  #  end of 'env' or 'argv' ?
	blss	L2
	tstl	-(r0)  # envp's are in list
L2:
	movl	r0,8(sp)  #  env
	movl	r0,_environ  #  indir is 0 if no env ; not 0 if env
	calls	$3,_main
	pushl	r0
	calls	$1,_exit
	chmk	$exit
#
	.data
_environ:	.space	4
Commit	Line	Data
18e5fa7e BJ	1	# C runtime startoff
	2
	3	.set exit,1
	4	.globl _exit
	5	.globl start
	6	.globl _main
	7	.globl _environ
	8
	9	#
	10	# C language startup routine
	11
	12	start:
	13	.word 0x0000
	14	subl2 $8,sp
	15	movl 8(sp),(sp) # argc
	16	movab 12(sp),r0
	17	movl r0,4(sp) # argv
	18	L1:
	19	tstl (r0)+ # null args term ?
	20	bneq L1
	21	cmpl r0,*4(sp) # end of 'env' or 'argv' ?
	22	blss L2
	23	tstl -(r0) # envp's are in list
	24	L2:
	25	movl r0,8(sp) # env
	26	movl r0,_environ # indir is 0 if no env ; not 0 if env
	27	calls $3,_main
	28	pushl r0
	29	calls $1,_exit
	30	chmk $exit
	31	#
	32	.data
	33	_environ: .space 4