V7/usr/src/libc/sys/mpxcall.s

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.globl _mpxcall, cerror

_mpxcall:
	mov	r5,-(sp)
	mov	sp,r5
	mov	4(r5),0f
	mov	6(r5),0f+2
call:
	sys	0; 9f
	bec	1f
	jmp	cerror
1:
	mov	(sp)+,r5
	rts	pc
.data
9:
	sys	56.; 0:..; ..