Minor improvements, code cleanup and license clarification

[fw/sdcc] / device / lib / z80 / mul.s

diff --git a/device/lib/z80/mul.s b/device/lib/z80/mul.s
index cba10dfe93ce6edd1fadc4b591e91c68f99ac60e..61ff5cf34179e99e6ab25d8ac8c2726725d46555 100644 (file)
--- a/device/lib/z80/mul.s
+++ b/device/lib/z80/mul.s
@@ -18,30 +18,29 @@ __mulint_rrx_s::
 __muluchar_rrx_hds::
 __mulint_rrx_hds::
        ;; Parameters:
-       ;;      HL, DE (left, right irrelevant)
+       ;;      hl, de (left, right irrelevant)
        ld      b,h
        ld      c,l
 
        ;; 16-bit multiplication
        ;;
        ;; Entry conditions
-       ;;   BC = multiplicand
-       ;;   DE = multiplier
+       ;; bc = multiplicand
+       ;; de = multiplier
        ;;
        ;; Exit conditions
-       ;;   DE = less significant word of product
+       ;; hl = less significant word of product
        ;;
        ;; Register used: AF,BC,DE,HL
 __mul16::
-        ld      l,#0
-        ld      a,b
-        ld      b,#16
+       xor     a,a
+       ld      l,a
+       or      a,b
+       ld      b,#16
 
         ;; Optimise for the case when this side has 8 bits of data or
         ;; less.  This is often the case with support address calls.
-        or      a
         jr      NZ,2$
-
         ld      b,#8
         ld      a,c
 1$: