From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 13913 invoked by alias); 29 Mar 2008 04:16:02 -0000 Received: (qmail 13905 invoked by uid 22791); 29 Mar 2008 04:16:01 -0000 X-Spam-Check-By: sourceware.org Received: from wf-out-1314.google.com (HELO wf-out-1314.google.com) (209.85.200.174) by sourceware.org (qpsmtpd/0.31) with ESMTP; Sat, 29 Mar 2008 04:15:43 +0000 Received: by wf-out-1314.google.com with SMTP id 28so522322wfc.14 for ; Fri, 28 Mar 2008 21:15:39 -0700 (PDT) Received: by 10.142.216.9 with SMTP id o9mr2483171wfg.93.1206764139896; Fri, 28 Mar 2008 21:15:39 -0700 (PDT) Received: by 10.142.192.14 with HTTP; Fri, 28 Mar 2008 21:15:39 -0700 (PDT) Message-ID: <1807a3db0803282115u5a825d65k7c0c2bb252d8b178@mail.gmail.com> Date: Sat, 29 Mar 2008 04:16:00 -0000 From: QiangHuang To: gcc-help Subject: V_MUST_DEF vs V_MAY_DEF ? MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline X-IsSubscribed: yes Mailing-List: contact gcc-help-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-help-owner@gcc.gnu.org X-SW-Source: 2008-03/txt/msg00294.txt.bz2 "V_MUST_DEF" and "V_MAY_DEF" , The two tags appear in the IL of SSA in GCC.I know they have something to do with the virtual operand,however,I wonder that what the exact distinction between them is. Corresponding to the 2 tags, is there "V_MUST_USE" or "V_MAY_USE"? Thanks a lot~^_^