From patchwork Fri Jan 9 11:25:20 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Frediano Ziglio X-Patchwork-Id: 427044 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id B34C1140182 for ; Fri, 9 Jan 2015 22:26:16 +1100 (AEDT) Received: from localhost ([::1]:50100 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y9Xhm-0005dG-Of for incoming@patchwork.ozlabs.org; Fri, 09 Jan 2015 06:26:14 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39787) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y9Xh8-0004rW-1U for qemu-devel@nongnu.org; Fri, 09 Jan 2015 06:25:35 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Y9Xh3-0002Z5-01 for qemu-devel@nongnu.org; Fri, 09 Jan 2015 06:25:33 -0500 Received: from mail-wi0-x229.google.com ([2a00:1450:400c:c05::229]:45404) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Y9Xh2-0002Yx-QJ for qemu-devel@nongnu.org; Fri, 09 Jan 2015 06:25:28 -0500 Received: by mail-wi0-f169.google.com with SMTP id r20so1728592wiv.0 for ; Fri, 09 Jan 2015 03:25:28 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=from:to:cc:subject:date:message-id; bh=OUxgPN2K2cYtzyG0k9jAubo/gJ6Z9yFJyPICPze9AYc=; b=bHbhTJYpYOKafdJiURJLA6IjIAYvxiPOxgDQKOhIsdGvM+PVCuMQpmP503grGXG0Pn Avra9E5zGuTruh9RjOqLLGkZ4Hf+glPR1Gn8/gM/rOz872Mqi54H7ATm+jvHdaOGCh5X wsax2pcafdT18eR99gUM4z7/MKHdW+SSej1xGOHJC5cGnyOuShpO5fvV2YUAhXeGyx6X +9Cx4+sW/qBCKXJZn5tMO7mQ2BKMuapweM6vSksbk7uTF8hSd6Ixq/pRxEE0m428RcyM QMcx+Q1V8dvsZWMWtm5QbHNsddg2ygfV+fi0s+w2EG9R9+m3Dh72iuR3mCtl26mZwclM g9Iw== X-Received: by 10.180.208.79 with SMTP id mc15mr4249501wic.34.1420802728189; Fri, 09 Jan 2015 03:25:28 -0800 (PST) Received: from localhost.localdomain ([90.152.119.35]) by mx.google.com with ESMTPSA id hz9sm9650753wjb.17.2015.01.09.03.25.27 (version=TLSv1.2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Fri, 09 Jan 2015 03:25:27 -0800 (PST) From: Frediano Ziglio X-Google-Original-From: Frediano Ziglio To: Paolo Bonzini , Anthony Liguori , Stefan Hajnoczi Date: Fri, 9 Jan 2015 11:25:20 +0000 Message-Id: <1420802721-14457-1-git-send-email-frediano.ziglio@huawei.com> X-Mailer: git-send-email 1.9.1 X-detected-operating-system: by eggs.gnu.org: Error: Malformed IPv6 address (bad octet value). X-Received-From: 2a00:1450:400c:c05::229 Cc: Frediano Ziglio , qemu-devel@nongnu.org Subject: [Qemu-devel] [PATCH 1/2] qemu-common.h: optimise muldiv64 if int128 is available X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Let compiler do the job to optimise the function. Signed-off-by: Frediano Ziglio --- include/qemu-common.h | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/include/qemu-common.h b/include/qemu-common.h index f862214..f3033ae 100644 --- a/include/qemu-common.h +++ b/include/qemu-common.h @@ -370,6 +370,12 @@ static inline uint8_t from_bcd(uint8_t val) } /* compute with 96 bit intermediate result: (a*b)/c */ +#ifdef CONFIG_INT128 +static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c) +{ + return (__int128)a * b / c; +} +#else static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c) { union { @@ -392,6 +398,7 @@ static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c) res.l.low = (((rh % c) << 32) + (rl & 0xffffffff)) / c; return res.ll; } +#endif /* Round number down to multiple */ #define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m))