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From: Alan Modra <amodra@gmail.com>
To: Fangrui Song <i@maskray.me>
Cc: Haim Shimonovich <Haim.Shimonovich@ceva-dsp.com>,
	"binutils@sourceware.org" <binutils@sourceware.org>
Subject: Re: objdump very long run time when using -D -z flags
Date: Fri, 1 May 2020 13:52:05 +0930	[thread overview]
Message-ID: <20200501042205.GC25855@bubble.grove.modra.org> (raw)
In-Reply-To: <BN7PR15MB22741FE56EAB113951280EFFCBAB0@BN7PR15MB2274.namprd15.prod.outlook.com>

On Thu, Apr 30, 2020 at 06:22:11PM -0700, Fangrui Song wrote:
> This just hides the problem.

That isn't true.

> -z is still going to be slow.

Well, yes, because objdump is going to be showing many instructions.

> To avoid
> the quadratic behavior, we should increase the address by at least `z`
> if we have scanned `z` zeros.

What quadratic behaviour related to blocks of zeros?  With -z we now
won't scan, and without -z the entire block (or almost) is consumed.

-- 
Alan Modra
Australia Development Lab, IBM

  reply	other threads:[~2020-05-01  4:22 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-04-30 14:26 Haim Shimonovich
2020-05-01  1:22 ` Fangrui Song
2020-05-01  4:22   ` Alan Modra [this message]
2020-05-01  4:13 ` Alan Modra

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