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Date: Thu, 8 Feb 2018 11:13:48 +0100
From: Peter Zijlstra <peterz@infradead.org>
To: David Laight <David.Laight@ACULAB.COM>
Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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Subject: Re: [linus:master] BUILD REGRESSION
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On Thu, Feb 08, 2018 at 09:47:53AM +0000, David Laight wrote:
> From: Peter Zijlstra

> > I went through the register opcodes and matched it against the ModR/M
> > encoding, and the best option I've found so far is using 0xd6 as the
> > next byte.
> 
> Wouldn't 0xc3 work as well.
> A retq is probably better than an extra (bad).

I explicity did not use c3 because that generates spurious "retq" in the
code flow which is mighty confusing when you read the stuff.