Re: Patch to remove undefined C code

From: Bernd Schmidt (bernds@redhat.co.uk)
Date: Tue Oct 17 2000 - 04:40:12 EST


> Looking at the above code, I noticed that there are a lot of ++
> operations. I rewrote the code as:
>
> setup_from[0] = setup_from[1] = eaddrs[0];
> setup_from[2] = setup_from[3] = eaddrs[1];
> setup_from[4] = setup_from[5] = eaddrs[2];
> setup_from += 6;
>
> I compiled using "gcc -S -Wall -O2 -fomit-frame-pointer -m486" to generate
> the assembler code. The old code is 17 instructions long and the new code
> is 11 instructions. As well as being shorter, simple timing test indicate
> that the new code is significantly quicker.

This is something the compiler ought to know about.

Bernd

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