Add original unix v6

source/s4/fltpr.s

@@ -0,0 +1,91 @@
+/ C library-- floating output
+
+.globl	pfloat
+.globl	pscien
+.globl	fltused
+
+.globl	_ndigit
+.globl	ecvt
+.globl	fcvt
+
+fltused:		/ force loading
+pfloat:
+	mov	r0,_ndigit
+	tst	r2
+	bne	1f
+	mov	$6,_ndigit
+1:
+	movf	(r4)+,fr0
+	jsr	pc,fcvt
+	tst	r1
+	beq	1f
+	movb	$'-,(r3)+
+1:
+	tst	r2
+	bgt	1f
+	movb	$'0,(r3)+
+1:
+	mov	r2,r1
+	ble	1f
+2:
+	movb	(r0)+,(r3)+
+	sob	r1,2b
+1:
+	mov	_ndigit,r1
+	beq	1f
+	movb	$'.,(r3)+
+1:
+	neg	r2
+	ble	1f
+2:
+	dec	r1
+	blt	1f
+	movb	$'0,(r3)+
+	sob	r2,2b
+1:
+	tst	r1
+	ble	2f
+1:
+	movb	(r0)+,(r3)+
+	sob	r1,1b
+2:
+	rts	pc
+
+pscien:
+	mov	r0,_ndigit
+	tst	r2
+	bne	1f
+	mov	$6,_ndigit
+1:
+	movf	(r4)+,fr0
+	jsr	pc,ecvt
+	tst	r1
+	beq	1f
+	movb	$'-,(r3)+
+1:
+	movb	(r0)+,(r3)+
+	movb	$'.,(r3)+
+	mov	_ndigit,r1
+	dec	r1
+	ble	1f
+2:
+	movb	(r0)+,(r3)+
+	sob	r1,2b
+1:
+	movb	$'e,(r3)+
+	dec	r2
+	mov	r2,r1
+	bge	1f
+	movb	$'-,(r3)+
+	neg	r1
+	br	2f
+1:
+	movb	$'+,(r3)+
+2:
+	clr	r0
+	div	$10.,r0
+	add	$'0,r0
+	movb	r0,(r3)+
+	add	$'0,r1
+	movb	r1,(r3)+
+	rts	pc