Re: A89: Line 1111 Emulator
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Re: A89: Line 1111 Emulator
Sorry for the ambiguous pronouns; I was saying that the lea one would be
faster since it uses relative addressing.
>
>You mean that add.l #10,a7 is shorter than lea 10(a7),a7 ?
>In this case you are wrong; add.l #10,a7 is longer because of the size
>(long word) of the immediate value #10.
>
>
>> I have no idea whether it's faster, but it is, I think, at least two
bytes
>> shorter since <lea 10(a7),a7> uses relative addressing over absolute.
>> Also, <lea 10(a7),a7> _isn't_ reading any memory; a7 is in parenthesis,
but
>> the lea makes the operand an address register and then ten is added to
that
>> (a7+10, not (a7)+10).
>>
>> >
>> >Wouldn't add.l 10, a7 be faster then doing it with lea?
>> >Generally, (at least on the Intel processors), adding an immediate to a
>> >register is faster than setting a memory address to a register.
>> >
>> >Daniel Imfeld
>> >
>
>--
>
>Xavier VASSOR
>---The Doors Team
>E-mail:xvassor@mail.dotcom.fr
>Doors Homepage: http://start.at/doors
>ICQ:10241721
>