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Subject: Re: More efficient bitswap.s

Re: More efficient bitswap.s

From: Magnus Holmgren <lear_at_algonet.se>
Date: Thu, 24 Oct 2002 14:21:51 +0200 (MEST)

Ray Ransom wrote:

> Here is a more efficient version of bitswap.s. It has one less instruction
> in the all-important loop, fewer instructions in the initial test and uses
> fewer registers. If any cares, it's attached.

The last byte swap isn't correct:

        mov.b _at_r4,r1
        extu.b r0,r1
        mov.b _at_(r0,r1),r1
        mov.b r1,_at_r4

Should be "extu.b r1,r1" (as in the first byte swap).

  Magnus
Received on 2002-10-24

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