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Subject: Re: [tip:x86/asm] x86/defconfig: Turn on CONFIG_CC_OPTIMIZE_FOR_SIZE= y in the 64-bit defconfig
From: "H. Peter Anvin" <hpa@zytor.com>
Date: Sat, 26 Jan 2013 13:04:40 -0800
To: Steven Rostedt <rostedt@goodmis.org>,
        Linus Torvalds <torvalds@linux-foundation.org>
CC: Borislav Petkov <bp@alien8.de>, Ingo Molnar <mingo@kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Arjan van de Ven <arjan@linux.intel.com>,
        Jan Beulich <jbeulich@suse.com>, ling.ml@alipay.com,
        Andrew Morton <akpm@linux-foundation.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        linux-tip-commits@vger.kernel.org
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We have discussed -Ok(ernel) with the gcc guys in earnest.  They are receptive but lack the round tuits.

Steven Rostedt <rostedt@goodmis.org> wrote:

>On Sat, 2013-01-26 at 11:43 -0800, Linus Torvalds wrote:
>
>> The problem, of course, is that most -O2 code generation is done
>> assuming hot loops that don't show much if any I$ issues. And the -Os
>> thing is done *purely* for size, not taking any performance into
>> account at all. There's no balanced middle ground, which is what _we_
>> would want.
>
>Gcc needs to implement a -Olinus
>
>;-)
>
>-- Steve

-- 
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