Re: Code optimization <LEA Instruction>

From: Alan Cox (alan@lxorguk.ukuu.org.uk)
Date: Thu Jan 27 2000 - 18:05:12 EST


> One of the things it states is that the LEA instruction can
> be used to change the value of an index register faster than
> using the ADD instruction (Page G-10, Intel '486 Rag).

It is

>
> As usual, the Intel reference manual is wrong for all types
> of CPUs that I have tested (486-686).

Your test is wrong. See the notes on address generation stalls

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