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Date: Tue, 31 May 2016 20:05:19 +1000
From: Anton Blanchard <anton@samba.org>
To: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>, Paul Mackerras
 <paulus@samba.org>, Michael Ellerman <mpe@ellerman.id.au>, Scott Wood
 <oss@buserror.net>, linuxppc-dev@lists.ozlabs.org,
 linux-kernel@vger.kernel.org
Subject: Re: [PATCH] powerpc: inline current_stack_pointer()
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Hi,

> current_stack_pointeur() is a single instruction function. it
> It is not worth breaking the execution flow with a bl/blr for a
> single instruction

Check out bfe9a2cfe91a ("powerpc: Reimplement __get_SP() as a function
not a define") to see why we made it a function.

Anton