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Re: [avr-gcc-list] suggestion
From: |
Royce Pereira |
Subject: |
Re: [avr-gcc-list] suggestion |
Date: |
Wed, 05 Jul 2006 21:08:04 +0530 |
User-agent: |
Opera Mail/9.00 (Win32) |
Hi,
On Wed, 05 Jul 2006 17:57:50 +0530, <address@hidden> wrote:
> I'm a total newbie to avr-gcc and just compiled a first program. It merely
> fits the program memory so I've started to optimize..
>
> In my code there lots of places where 1-2-3 bits are flipped in I/O port:
>
>
>
> My suggestion is to optimize the case when 2 bits are set into 2 sbi
> commands, and when 2 bits are cleared into 2 cbi commands. It's quite
> easy to count number of 1s or 0s in the mask - and if there are exacly
> 2, apply this optimization.
Wherever you require this, just use 2 separate bit setting/ clearing statements
in your C code itself.
--Royce.
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