findfirstbit.s

来自「NXP LPC3000系列 wince BSP包」· S 代码 · 共 35 行

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; which provides customers with programming information regarding the  
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; Copyright NXP Semiconductors
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;
; findfirstbit.s
;
; Returns first active bit in a passed value
;

        OPT     2       ; disable listing
        INCLUDE kxarm.h
        OPT     1       ; reenable listing
		
        TEXTAREA
	
        LEAF_ENTRY findfirstbit
        clz   r0, r0
        rsb   r0, r0, #31
        bx    lr
        ENTRY_END

        END

; EOF oemabort.s