Re: [PATCH 1/1] x86: Convert cpuinfo_x86 array to a per_cpu arrayv3

From: Dave Jones
Date: Mon Sep 24 2007 - 20:31:53 EST


On Tue, Sep 25, 2007 at 02:20:01AM +0200, roel wrote:

> > > > if ((c->x86_vendor != X86_VENDOR_AMD) || (c->x86 != 5) ||
> > > > ((c->x86_model != 12) && (c->x86_model != 13)))
> > >
> > > while we're at it, we could change this to
> > >
> > > if (!(c->x86_vendor == X86_VENDOR_AMD && c->x86 == 5 &&
> > > (c->x86_model == 12 || c->x86_model == 13)))
> >
> > For what purpose? There's nothing wrong with the code as it stands,
> > and inverting the tests means we'd have to move a bunch of
> > code inside the if arm instead of just returning -ENODEV.
>
> It's not inverting the test, so you don't need to move code. It evaluates
> the same, only the combined negation is moved to the front. I suggested it
> to increase clarity, it results in the same assembly language.

I don't see it as being particularly more readable after this change.
In fact, the reverse, as my previous comment implied, I missed the
initial !
Given this code works fine, and there's no discernable gain from
changing it, I'm not particularly enthusiastic about this modification.

Dave

--
http://www.codemonkey.org.uk
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