From patchwork Wed Apr 16 16:46:11 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bandan Das X-Patchwork-Id: 4002891 Return-Path: X-Original-To: patchwork-kvm@patchwork.kernel.org Delivered-To: patchwork-parsemail@patchwork2.web.kernel.org Received: from mail.kernel.org (mail.kernel.org [198.145.19.201]) by patchwork2.web.kernel.org (Postfix) with ESMTP id 59B8CBFF02 for ; Wed, 16 Apr 2014 16:50:32 +0000 (UTC) Received: from mail.kernel.org (localhost [127.0.0.1]) by mail.kernel.org (Postfix) with ESMTP id 92C3B2034F for ; Wed, 16 Apr 2014 16:50:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id ACC182034E for ; Wed, 16 Apr 2014 16:50:30 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754322AbaDPQt4 (ORCPT ); Wed, 16 Apr 2014 12:49:56 -0400 Received: from mx1.redhat.com ([209.132.183.28]:11715 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752496AbaDPQqa (ORCPT ); Wed, 16 Apr 2014 12:46:30 -0400 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s3GGkTQq021729 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Wed, 16 Apr 2014 12:46:29 -0400 Received: from nelium.bos.redhat.com ([10.18.25.173]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id s3GGkPv0000914; Wed, 16 Apr 2014 12:46:28 -0400 From: Bandan Das To: kvm@vger.kernel.org Cc: Marcelo Tosatti , Paolo Bonzini , Gleb Natapov , linux-kernel@vger.kernel.org Subject: [RFC PATCH v3 3/6] KVM: emulate: cleanup decode_modrm Date: Wed, 16 Apr 2014 12:46:11 -0400 Message-Id: <1397666774-24713-4-git-send-email-bsd@redhat.com> In-Reply-To: <1397666774-24713-1-git-send-email-bsd@redhat.com> References: <1397666774-24713-1-git-send-email-bsd@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.11 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Spam-Status: No, score=-7.6 required=5.0 tests=BAYES_00, RCVD_IN_DNSWL_HI, RP_MATCHES_RCVD, UNPARSEABLE_RELAY autolearn=unavailable version=3.3.1 X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on mail.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Remove the if conditional - that will help us avoid an "else initialize to 0" Also, rearrange operators for slightly better code. Signed-off-by: Bandan Das --- arch/x86/kvm/emulate.c | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index a6d9892..e12ac87 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -1064,19 +1064,17 @@ static int decode_modrm(struct x86_emulate_ctxt *ctxt, struct operand *op) { u8 sib; - int index_reg = 0, base_reg = 0, scale; + int index_reg, base_reg, scale; int rc = X86EMUL_CONTINUE; ulong modrm_ea = 0; - if (ctxt->rex_prefix) { - ctxt->modrm_reg = (ctxt->rex_prefix & 4) << 1; /* REX.R */ - index_reg = (ctxt->rex_prefix & 2) << 2; /* REX.X */ - ctxt->modrm_rm = base_reg = (ctxt->rex_prefix & 1) << 3; /* REG.B */ - } + ctxt->modrm_reg = ((ctxt->rex_prefix << 1) & 8); /* REX.R */ + index_reg = (ctxt->rex_prefix << 2) & 8; /* REX.X */ + base_reg = (ctxt->rex_prefix << 3) & 8; /* REX.B */ - ctxt->modrm_mod |= (ctxt->modrm & 0xc0) >> 6; + ctxt->modrm_mod = (ctxt->modrm & 0xc0) >> 6; ctxt->modrm_reg |= (ctxt->modrm & 0x38) >> 3; - ctxt->modrm_rm |= (ctxt->modrm & 0x07); + ctxt->modrm_rm = base_reg | (ctxt->modrm & 0x07); ctxt->modrm_seg = VCPU_SREG_DS; if (ctxt->modrm_mod == 3) {