From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 120536 invoked by alias); 6 May 2015 19:18:23 -0000 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 Received: (qmail 120527 invoked by uid 89); 6 May 2015 19:18:23 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-3.8 required=5.0 tests=AWL,BAYES_00,SPF_HELO_PASS,SPF_PASS,T_RP_MATCHES_RCVD autolearn=ham version=3.3.2 X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES256-GCM-SHA384 encrypted) ESMTPS; Wed, 06 May 2015 19:18:22 +0000 Received: from int-mx14.intmail.prod.int.phx2.redhat.com (int-mx14.intmail.prod.int.phx2.redhat.com [10.5.11.27]) by mx1.redhat.com (Postfix) with ESMTPS id 5F46C39EC46 for ; Wed, 6 May 2015 19:18:21 +0000 (UTC) Received: from host1.jankratochvil.net (ovpn-116-27.ams2.redhat.com [10.36.116.27]) by int-mx14.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id t46JIHVL008872 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Wed, 6 May 2015 15:18:19 -0400 Date: Wed, 06 May 2015 19:18:00 -0000 From: Jan Kratochvil To: Pedro Alves Cc: gdb-patches@sourceware.org, Phil Muldoon Subject: Re: [PATCH v3 7/9] compile: New 'compile print' Message-ID: <20150506191816.GA12839@host1.jankratochvil.net> References: <20150411194322.29128.52477.stgit@host1.jankratochvil.net> <20150411194418.29128.3411.stgit@host1.jankratochvil.net> <5540FD9E.1020005@redhat.com> <20150503140557.GB18394@host1.jankratochvil.net> <5549EB49.2050206@redhat.com> <20150506122301.GA20986@host1.jankratochvil.net> <554A20F3.1010404@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <554A20F3.1010404@redhat.com> User-Agent: Mutt/1.5.23 (2014-03-12) X-IsSubscribed: yes X-SW-Source: 2015-05/txt/msg00129.txt.bz2 On Wed, 06 May 2015 16:10:59 +0200, Pedro Alves wrote: > On 05/06/2015 01:23 PM, Jan Kratochvil wrote: > > This is all a hack how to get it working for live targets without implementing > > the compiler IR (intermediate representation) interpreter in GDB (making > > 'compile' commands compatible with core files). So far AFAIK C++ live > > functionality has been a top priority, not the IR interpreter. This > > COMPILE_I_PRINT_ADDRESS_SCOPE-or-COMPILE_I_PRINT_VALUE_SCOPE conditional would > > be some simple runtime conditional in the IR interpreter instead. > > > > If an implementation on top of IR interpreter is required for these patches > > then this whole patch series should be dropped and we need to start to work on > > the IR interpreter instead. > > No, IR interpreter is certainly not a requirement. IIUC in this case the hack has an acceptable scale (contrary to that printf). > But I think the comment that explains the current implementation should > be clear. As is, it's just that I still don't understand what you mean by: > > > Function returns NULL only for COMPILE_I_PRINT_ADDRESS_SCOPE when > > COMPILE_I_PRINT_VALUE_SCOPE should have been used instead. > > because reading this one wonders: "OK, if COMPILE_I_PRINT_VALUE_SCOPE should > have been used, why wasn't it used then? Is that a bug in the caller?" I have put there now: GDB first tries to compile the code with COMPILE_I_PRINT_ADDRESS_SCOPE. If it finds user tries to print an array type this function returns NULL. Caller will then regenerate the code with COMPILE_I_PRINT_VALUE_SCOPE, recompiles it again and finally runs it. This is because __auto_type array-to-pointer type conversion of COMPILE_I_EXPR_VAL which gets detected by COMPILE_I_EXPR_PTR_TYPE preserving the array type. */ Plus at: enum compile_i_scope_types name already specifies its address. See get_out_value_type. */ COMPILE_I_PRINT_ADDRESS_SCOPE, COMPILE_I_PRINT_VALUE_SCOPE, Jan