Added 16*16=32 multiplication routine.

git-svn-id: svn://svn.cc65.org/cc65/trunk@4434 b7a2c559-68d2-44c3-8de9-860c34a00d81
2009-11-03 13:40:03 +00:00
parent 6078953baa
commit 0c1703f8fd
3 changed files with 54 additions and 4 deletions
--- a/libsrc/runtime/mul8x8r16.s
+++ b/libsrc/runtime/mul8x8r16.s
@@ -4,7 +4,8 @@
 ; CC65 runtime: 8x8 => 16 multiplication
 ;

-       	.export		mul8x8r16, umul8x8r16
+       	.export		umul8x8r16
+        .export         mul8x8r16 := umul8x8r16
    	.importzp	ptr1, ptr3


@@ -13,10 +14,9 @@
 ;
 ;   lhs         rhs           result          result also in
 ; -------------------------------------------------------------
-;   ptr1-lo     ptr3-lo         a/x             ptr1
+;   ptr1-lo     ptr3-lo         ax              ptr1
 ;

-mul8x8r16:
 umul8x8r16:
    	lda   	#0              ; Clear byte 1
       	ldy    	#8    	       	; Number of bits
@@ -28,7 +28,7 @@ umul8x8r16:
        ror     ptr1
        dey
        bne     @L0
-        tax         
+        tax
        stx     ptr1+1          ; Result in a/x and ptr1
    	lda	ptr1  	       	; Load the result
    	rts	   		; Done