cc65/libsrc/common/_umul16x8r32.s

28 lines
590 B
ArmAsm

;
; Ullrich von Bassewitz, 2011-07-10
;
; CC65 library: 16x8 => 32 unsigned multiplication
;
.export _umul16x8r32
.import umul8x16r24, popax
.include "zeropage.inc"
;---------------------------------------------------------------------------
; 16x8 => 32 unsigned multiplication routine. We use 8x16 => 24 and clear
; the high byte of the result
.proc _umul16x8r32
sta ptr1
lda #0
sta sreg+1 ; Clear high byte of result
jsr popax
jmp umul8x16r24
.endproc