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Subject: Re: [PATCH 3/4] KVM-S390: Less function calls in
 kvm_s390_import_bp_data() after error detection
To: SF Markus Elfring <elfring@users.sourceforge.net>,
        Cornelia Huck <cornelia.huck@de.ibm.com>
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From: Paolo Bonzini <pbonzini@redhat.com>
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Date: Wed, 31 Aug 2016 14:29:41 +0200
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On 22/08/2016 23:17, SF Markus Elfring wrote:
>> If in doubt, the compiler will be _much_ better at optimizing
>> that kind of stuff anyway.
> 
> Which compiler (or optimizer) implementation is capable to restructure
> the jump targets for you automatically in the way I propose here?

If kfree were implemented as

	if (p)
		really_kfree(p);

then the compiler would be able to jump over the NULL test.  In
principle one could also add a "does nothing if NULL" attribute to GCC
and annotate kfree with it.

Paolo