Add original unix v6

source/fort/io/io1.s

@@ -0,0 +1,78 @@
+/
+/
+
+/ io1 --  I/O operators
+
+
+.globl	rerr
+.globl	endio
+.globl	rio4
+.globl	rio8
+.globl	iio2
+.globl	iio4
+.globl	lio2
+.globl	lio1
+.globl	cio8
+.globl	cio16
+.globl	ecvt
+.globl	fcvt
+.globl	_ndigit
+
+endio:
+	mov	(sp)+,r5
+	rts	r5
+
+cio8:
+	tst	slcnt
+	bne	2f
+	inc	slcnt
+	tst	-(r4)
+	br	rio4
+2:
+	clr	slcnt
+	mov	ilval,-(sp)
+	add	$4,(sp)
+	br	rio4
+
+cio16:
+	tst	slcnt
+	bne	2f
+	inc	slcnt
+	tst	-(r4)
+	br	rio8
+2:
+	clr	slcnt
+	mov	ilval,-(sp)
+	add	$8,(sp)
+	br	rio8
+
+rio8:
+	mov	$8.\<8+'r,r0
+	br	1f
+
+rio4:
+	mov	$4\<8+'r,r0
+	br	1f
+
+iio4:
+	mov	$4\<8+'i,r0
+	br	1f
+
+iio2:
+	mov	$2\<8+'i,r0
+	br	1f
+
+lio2:
+	mov	$2\<8+'l,r0
+	br	1f
+
+lio1:
+	mov	$1\<8+'l,r0
+
+1:
+	mov	r0,itype
+	mov	(sp)+,ilval
+	mov	(sp)+,r5
+	tst	(r5)+
+	rts	r5
+