From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 6890 invoked by alias); 23 Dec 2010 09:11:07 -0000 Received: (qmail 6882 invoked by uid 22791); 23 Dec 2010 09:11:05 -0000 X-SWARE-Spam-Status: No, hits=-2.1 required=5.0 tests=AWL,BAYES_00,T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from sibelius.xs4all.nl (HELO glazunov.sibelius.xs4all.nl) (83.163.83.176) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Thu, 23 Dec 2010 09:10:59 +0000 Received: from glazunov.sibelius.xs4all.nl (kettenis@localhost [127.0.0.1]) by glazunov.sibelius.xs4all.nl (8.14.3/8.14.3) with ESMTP id oBN99O1r020983; Thu, 23 Dec 2010 10:09:24 +0100 (CET) Received: (from kettenis@localhost) by glazunov.sibelius.xs4all.nl (8.14.3/8.14.3/Submit) id oBN99NIJ024314; Thu, 23 Dec 2010 10:09:23 +0100 (CET) Date: Thu, 23 Dec 2010 12:04:00 -0000 Message-Id: <201012230909.oBN99NIJ024314@glazunov.sibelius.xs4all.nl> From: Mark Kettenis To: brobecker@adacore.com CC: yao@codesourcery.com, gdb-patches@sourceware.org In-reply-to: <20101223042236.GS2596@adacore.com> (message from Joel Brobecker on Thu, 23 Dec 2010 08:22:36 +0400) Subject: Re: [rfa] Update PC without side effect in displaced stepping References: <4D0F0ABA.9010506@codesourcery.com> <201012200804.oBK84oPu005379@glazunov.sibelius.xs4all.nl> <4D0F5D36.2040909@codesourcery.com> <4D10D377.8080100@codesourcery.com> <20101223042236.GS2596@adacore.com> Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org X-SW-Source: 2010-12/txt/msg00432.txt.bz2 > Date: Thu, 23 Dec 2010 08:22:36 +0400 > From: Joel Brobecker > > > When writing the new patch, I re-consider this problem again. GDB > > doesn't support displaced stepping on sparc and hppa, so it is not > > harmful to sparc and hppa when regcache_write_pc is replaced by > > regcache_cooked_write_unsigned. > > Currently, GDB supports displaced stepping on s390, rs6000 (including > > ppc-linux, aix), i386, amd64 and arm. AFAICS, this replacement in my > > original patch is not harmful to these targets. > [...] > > Given my original patch is clean, and not harmful to existing targets > > support displaced stepping, please consider my original patch again. > > Comments on promising directions/approaches are welcome. > > I haven't seen the patch, so I cannot comment specifically, but I think > that you are using the wrong reasons to try to justify your initial > patch. It does not matter whether sparc or hppa support displaced > stepping or not. They might - it's not far-fetched for sparc, for > instance. Or other platforms where it matters might be contributed > in the future, and they could need displaced stepping too. By letting > your patch in, we would be making it harder for other platforms to > implement it. It would feel like sweeping the dust under the carpet... I have the same feeling.