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Date:   Thu, 15 Oct 2020 08:25:12 -0500
From:   Segher Boessenkool <segher@kernel.crashing.org>
To:     Christophe Leroy <christophe.leroy@csgroup.eu>
Cc:     Benjamin Herrenschmidt <benh@kernel.crashing.org>,
        Paul Mackerras <paulus@samba.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] powerpc: force inlining of csum_partial() to avoid multiple csum_partial() with GCC10
Message-ID: <20201015132512.GG2672@gate.crashing.org>
References: <a1d31f84ddb0926813b17fcd5cc7f3fa7b4deac2.1602759123.git.christophe.leroy@csgroup.eu>
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Hi!

On Thu, Oct 15, 2020 at 10:52:20AM +0000, Christophe Leroy wrote:
> With gcc9 I get:

<snip>

> With gcc10 I get:

<snip>

> gcc10 defines multiple versions of csum_partial() which are just
> an unconditionnal branch to __csum_partial().

It doesn't inline it, yes.

Could you open a GCC PR for this please?

> To enforce inlining of that branch to __csum_partial(),
> mark csum_partial() as __always_inline.

That should be fine of course, but it would be good if we could fix this
in the compiler :-)

Reviewed-by: Segher Boessenkool  <segher@kernel.crashing.org>


Segher