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Old 17 February 2019, 12:12   #45
Per aspera ad astra

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Join Date: Mar 2017
Location: Crossing the Rubicon
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Posts: 2,628
Originally Posted by Toni Wilen View Post
I'd say they are technically correct. I don't think those bit combinations are supposed to be used because instruction becomes plain move
Sure for most of them

But take this snippet:
	lea	$4.w,a0
	moveq	#0,d0
	move.l	a0,$0.w
	dc.b	$2c,$70,$09,%00010101
	dc.b	$2c,$70,$09,%10010101
That disassemble to:
00642376 41f8 0004                LEA.L $0004,A0
0064237A 7000                     MOVE.L #$00,D0
0064237C 21c8 0000                MOVE.L A0,$0000 [00000004]
00642380 2c70 0915                MOVEA.L ([],D0.L) == $00000004 [002008d4],A6
00642384 2c70 0995                MOVEA.L ([],D0.L) == $00000004 [002008d4],A6
Considering the bits encoding, first move to A6 rightly insert the indirect base content (what is at offset 0 of execbase).
You've execbase in A6 only in the later move, because base is suppressed.
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