From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Thu, 4 Jan 2001 03:09:40 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Thu, 4 Jan 2001 03:09:30 -0500 Received: from ns1.netbauds.net ([194.207.240.11]:20486 "EHLO ns1.netbauds.net") by vger.kernel.org with ESMTP id ; Thu, 4 Jan 2001 03:09:22 -0500 Message-ID: <3A542F83.4BD3B30B@netbauds.net> Date: Thu, 04 Jan 2001 08:08:36 +0000 From: Darryl Miles X-Mailer: Mozilla 4.6 [en] (X11; I; Linux 2.4.0-test11 i686) X-Accept-Language: en MIME-Version: 1.0 To: hugang CC: linux-kernel@vger.kernel.org Subject: Re: Abort x86 assemble code Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org hugang wrote: > I have following code ,and I can not understand the mark line,who can tell me.thanks. > 00000ec7 xorl 0x400dec(,%eax,4),%ecx ????<-----------------What it to do. extern u_int32_t eax; extern u_int32_t ecx; { u_int32_t *ptr; ptr = (u_int32_t *)((eax * 4) + 0x400dec); ecx ^= *ptr; } Commonly used in the above form (with a fixed displacement) to access a 32bit value within an array of 32bit values. The array start offset would be hardwired at 0x400dec, the zero based index into the array is provided by eax. -- Darryl Miles - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/