From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 25972 invoked by alias); 14 May 2003 21:11:29 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 25938 invoked from network); 14 May 2003 21:11:28 -0000 Received: from unknown (HELO desire.geoffk.org) (12.235.88.42) by sources.redhat.com with SMTP; 14 May 2003 21:11:28 -0000 Received: (from geoffk@localhost) by desire.geoffk.org (8.11.6/8.11.6) id h4ELBOL11527; Wed, 14 May 2003 14:11:24 -0700 Date: Wed, 14 May 2003 21:11:00 -0000 From: Geoff Keating Message-Id: <200305142111.h4ELBOL11527@desire.geoffk.org> To: rth@redhat.com CC: mrs@apple.com, jason@redhat.com, gcc@gcc.gnu.org In-reply-to: <20030514073901.GA16863@redhat.com> (message from Richard Henderson on Wed, 14 May 2003 00:39:01 -0700) Subject: Re: __attribute__((cleanup(function)) versus try/finally References: <20030508204622.GB6901@redhat.com> <82B7548E-81A4-11D7-BD07-003065A77310@apple.com> <20030513212426.GD8273@redhat.com> <200305140114.h4E1EZD10819@desire.geoffk.org> <20030514073901.GA16863@redhat.com> X-SW-Source: 2003-05/txt/msg01447.txt.bz2 > X-Original-To: geoffk@foam.wonderslug.com > Date: Wed, 14 May 2003 00:39:01 -0700 > From: Richard Henderson > Cc: mrs@apple.com, jason@redhat.com, gcc@gcc.gnu.org > Mail-Followup-To: Richard Henderson , > Geoff Keating , mrs@apple.com, jason@redhat.com, > gcc@gcc.gnu.org > Content-Disposition: inline > User-Agent: Mutt/1.4i > X-OriginalArrivalTime: 14 May 2003 07:41:37.0074 (UTC) FILETIME=[3FDA1920:01C319EC] > > On Tue, May 13, 2003 at 06:14:35PM -0700, Geoff Keating wrote: > > I wasn't thinking of changing the prologue at all; the plan would be > > to make the object-code reader sufficiently robust that it can handle > > most routines, and to include a check for whether this particular > > routine can be handled by the object-code reader. The reader would > > do things like skip over opcodes that it didn't understand. > > I don't like this at all. There's no way we can make > this *that* robust. You need to have prologues in a > canonical form, no shrink-wrapping, no complicated block > reordering, etc. But that's the truly neat part of the plan, you don't need to make it robust. All you need is to be able to look at RTL and determine whether the object-code reader will be successful in deducing the unwind information; if it would get it wrong, you just output explicit unwind information. -- - Geoffrey Keating