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From: Richard Henderson <richard.henderson@linaro.org>
To: Helge Deller <deller@gmx.de>, qemu-devel@nongnu.org
Subject: Re: [RFC][PATCH] Reduce generated code by 3% by increasing MMU indices
Date: Sat, 5 Aug 2023 10:29:12 -0700	[thread overview]
Message-ID: <53a2d13f-b508-0dba-5f0a-1b158372d1a4@linaro.org> (raw)
In-Reply-To: <ZM59CkNZg5n4WXO3@p100>

On 8/5/23 09:47, Helge Deller wrote:
> Do we want to enable such an performance optimization?
> If so, I see two possibilities:
> 
> a) Re-define NB_MMU_MODES per target

No, we've just gotten rid of per target definitions of NB_MMU_MODES, on the way to being 
able to support multiple targets simultaneously.

This only affects x86, and for only 6 bytes per memory access.  While saving code size is 
a nice goal, I sincerely doubt you can measure any performance difference.

If there were a way to change no more than two lines of code, that would be fine.  But 
otherwise I don't see this as being worth making the rest of the code base any more complex.


r~


  reply	other threads:[~2023-08-05 17:30 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-08-05 16:47 [RFC][PATCH] Reduce generated code by 3% by increasing MMU indices Helge Deller
2023-08-05 17:29 ` Richard Henderson [this message]
2023-08-05 17:43   ` Helge Deller
2023-08-05 17:58     ` Richard Henderson
2023-08-05 19:40       ` Helge Deller
2023-08-05 20:04         ` Helge Deller
2023-08-05 20:54           ` Richard Henderson

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