From patchwork Mon Jun 24 21:24:19 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?C=C3=A9dric_Le_Goater?= X-Patchwork-Id: 13710125 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D0294C30653 for ; Mon, 24 Jun 2024 21:25:37 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1sLrBh-0002kG-Uf; Mon, 24 Jun 2024 17:25:21 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sLrBg-0002jS-Kk for qemu-devel@nongnu.org; Mon, 24 Jun 2024 17:25:20 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1sLrBf-0006Xt-81 for qemu-devel@nongnu.org; Mon, 24 Jun 2024 17:25:20 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1719264318; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=pf3crsaXWdyFaaFBZx2lWT6QT4DOfW0gEGrlwS9UmK0=; b=eecuSZW5Px4v1veNq5Ofx30/KDiNQjqDKxvjPZsn4IMcprgH/LOM3pvFsegjZP7U8a6tJC i+Pa087EzNW9pEdI5oyF0nv7HWlRXjbDrXJS4l+36fVVR/Yco+eyecWHunpHqdTaTAPxFm P+J1XfYaVlVU1w9D4G3EsIDyCItVbR0= Received: from mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-575-8SshEwuKOvyw2hQGHwYWnA-1; Mon, 24 Jun 2024 17:25:16 -0400 X-MC-Unique: 8SshEwuKOvyw2hQGHwYWnA-1 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 538551956083; Mon, 24 Jun 2024 21:25:15 +0000 (UTC) Received: from corto.redhat.com (unknown [10.39.192.49]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTP id 3D4991956054; Mon, 24 Jun 2024 21:25:13 +0000 (UTC) From: =?utf-8?q?C=C3=A9dric_Le_Goater?= To: qemu-devel@nongnu.org Cc: Alex Williamson , Zhenzhong Duan , =?utf-8?q?C=C3=A9dric_Le_Goater?= , Eric Auger , "Michael S . Tsirkin" Subject: [PULL 05/42] range: Introduce range_get_last_bit() Date: Mon, 24 Jun 2024 23:24:19 +0200 Message-ID: <20240624212456.350919-6-clg@redhat.com> In-Reply-To: <20240624212456.350919-1-clg@redhat.com> References: <20240624212456.350919-1-clg@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Received-SPF: pass client-ip=170.10.129.124; envelope-from=clg@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: 10 X-Spam_score: 1.0 X-Spam_bar: + X-Spam_report: (1.0 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.207, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_SBL_CSS=3.335, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org From: Zhenzhong Duan This helper get the highest 1 bit position of the upper bound. If the range is empty or upper bound is zero, -1 is returned. Suggested-by: Cédric Le Goater Signed-off-by: Zhenzhong Duan Reviewed-by: Eric Auger Reviewed-by: Michael S. Tsirkin --- include/qemu/range.h | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/include/qemu/range.h b/include/qemu/range.h index 205e1da76dc5b29327f590b8293a826ced63c25d..4ce694a398311a32e9b5e3ca97aed97c90c0ae09 100644 --- a/include/qemu/range.h +++ b/include/qemu/range.h @@ -20,6 +20,8 @@ #ifndef QEMU_RANGE_H #define QEMU_RANGE_H +#include "qemu/bitops.h" + /* * Operations on 64 bit address ranges. * Notes: @@ -217,6 +219,15 @@ static inline int ranges_overlap(uint64_t first1, uint64_t len1, return !(last2 < first1 || last1 < first2); } +/* Get highest non-zero bit position of a range */ +static inline int range_get_last_bit(Range *range) +{ + if (range_is_empty(range)) { + return -1; + } + return 63 - clz64(range->upb); +} + /* * Return -1 if @a < @b, 1 @a > @b, and 0 if they touch or overlap. * Both @a and @b must not be empty.