Re: [PATCH 2/8] KVM: x86: cleanup kvm_apic_match_*()

[Radim KrÄmÃÅ]

2015-02-02 15:28+0100, Paolo Bonzini:
> 
> 
> On 02/02/2015 15:26, Radim KrÄmÃÅ wrote:
> >>> > > +		return ((logical_id >> 4) == (mda >> 4))
> >>> > > +		       && (logical_id & mda & 0xf);
> > was merged as
> > 
> > +		return ((logical_id >> 4) == (mda >> 4))
> > +		       && (logical_id & mda & 0xf) != 0;
> > 
> > but it has to be parenthesized ('&&' has lower precedence than '!=').
> 
> Lower precedence means that the merged version is right (unless my brain
> went bonkers, which I cannot exclude).  "!=" has higher precedence and
> thus it is implicitly parenthesized.
> 
> In fact the first comparison could have its parentheses removed as well.

Yes, it could be,
  logical_id >> 4 == mda >> 4 && (logical_id & mda & 0xf) != 0

I missed the point and thought that you wanted to turn the whole
expression into bool, when it already was one.
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