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Subject: Re: sparc: bpf_jit: Move four assignments in bpf_jit_compile()
To: Julian Calaby <julian.calaby@gmail.com>
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Cc: sparclinux <sparclinux@vger.kernel.org>,
        Adam Buchbinder <adam.buchbinder@gmail.com>,
        Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        "David S. Miller" <davem@davemloft.net>, Rabin Vincent <rabin@rab.in>,
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        kernel-janitors <kernel-janitors@vger.kernel.org>,
        Julia Lawall <julia.lawall@lip6.fr>,
        Paolo Bonzini <pbonzini@redhat.com>
From: SF Markus Elfring <elfring@users.sourceforge.net>
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Date: Sun, 4 Sep 2016 07:00:22 +0200
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> Does this change improve the resulting binary?

I hope so. - I propose to give the refactorings "Reduce scope of variable"
and "Extract a function" (and the corresponding consequences) another look.


> I.e. does it make it smaller or faster?

It is generally possible that a specific code generation variant will also affect
the run time properties you mentioned.


> Otherwise this change is useless churn - you're making the code more
> complicated, longer and harder to read for practically no benefit.

I imagine that there other reasons you could eventually accept
for this use case, aren't there?

Regards,
Markus