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meynaf · 05 November 2021, 18:54

Now a small, interesting problem : i need to clear said bit to be able to loop on them. (Didn't think about that when posting...)
Like this :

Code:

; d2=input value, d1=tmp, d0=result
loop
 move.w d2,d1
 subq.w #1,d1
 not.w d1
 and.w d2,d1
 bfffo d1{0:32},d0
 eori.b #31,d0
(do something here with d0=bit#)
 eor.w d1,d2
 bne loop

Above eor method removes one instruction from the calculation but destroys actual value...

05 November 2021, 18:54	#7
meynaf son of 68k Join Date: Nov 2007 Location: Lyon / France Age: 51 Posts: 5,323	Now a small, interesting problem : i need to clear said bit to be able to loop on them. (Didn't think about that when posting...) Like this : Code: ; d2=input value, d1=tmp, d0=result loop move.w d2,d1 subq.w #1,d1 not.w d1 and.w d2,d1 bfffo d1{0:32},d0 eori.b #31,d0 (do something here with d0=bit#) eor.w d1,d2 bne loop Above eor method removes one instruction from the calculation but destroys actual value...