From patchwork Thu Jun 15 15:26:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Herve Codina X-Patchwork-Id: 13281405 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D84FFC001DE for ; Thu, 15 Jun 2023 15:27:50 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344937AbjFOP1T (ORCPT ); Thu, 15 Jun 2023 11:27:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57380 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345178AbjFOP0u (ORCPT ); Thu, 15 Jun 2023 11:26:50 -0400 Received: from relay9-d.mail.gandi.net (relay9-d.mail.gandi.net [IPv6:2001:4b98:dc4:8::229]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E8376E69; Thu, 15 Jun 2023 08:26:48 -0700 (PDT) X-GND-Sasl: herve.codina@bootlin.com DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1686842807; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=KvU8ZFxyfZKV+6P7AuATlkHtw3Ni6ol9j6yJo+Wq6as=; b=gSVlOJoXENawBNZO9Y85VfX5SMHoBy0URfunSBWmGPz24SHA3JnQmvTXbEBf4m36Zi0iNu D9KjdJ5IvwftgPQNnmQCnZ/u2dZSjxfC8lFQiVdkqTHUBwYKPVFJTt8++Z6m/FEpy8AIeH 9LJh3ilhX09pffu02QobJRaVH3nBJMGzdVxXAdgmCQS5RgfRK4y36ZG/nbSc+YGk183Tl1 YOegPKxjPMaEUJHi++5RHuiKDr6UFpCh26Te0TzF/yRo4azFD+Aln1ddAP2La3WI6lK2Ql wrfZe/YrT0ZXoDcfdM1UeX3GQro2Lm78vPmlMgVS5YoFUrnTVy6im48toe8g8Q== X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com X-GND-Sasl: herve.codina@bootlin.com Received: by mail.gandi.net (Postfix) with ESMTPA id 0391BFF814; Thu, 15 Jun 2023 15:26:45 +0000 (UTC) From: Herve Codina To: Herve Codina , Liam Girdwood , Mark Brown , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Jonathan Cameron , Lars-Peter Clausen , Jaroslav Kysela , Takashi Iwai , Kuninori Morimoto , Andy Shevchenko Cc: alsa-devel@alsa-project.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-iio@vger.kernel.org, Christophe Leroy , Thomas Petazzoni Subject: [PATCH v5 07/13] minmax: Introduce {min,max}_array() Date: Thu, 15 Jun 2023 17:26:25 +0200 Message-Id: <20230615152631.224529-8-herve.codina@bootlin.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230615152631.224529-1-herve.codina@bootlin.com> References: <20230615152631.224529-1-herve.codina@bootlin.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-iio@vger.kernel.org Introduce min_array() (resp max_array()) in order to get the minimal (resp maximum) of values present in an array. Signed-off-by: Herve Codina Reviewed-by: Andy Shevchenko --- include/linux/minmax.h | 64 ++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 64 insertions(+) diff --git a/include/linux/minmax.h b/include/linux/minmax.h index 396df1121bff..1672985b02a3 100644 --- a/include/linux/minmax.h +++ b/include/linux/minmax.h @@ -133,6 +133,70 @@ */ #define max_t(type, x, y) __careful_cmp((type)(x), (type)(y), >) +/* + * Remove a const qualifier from integer types + * _Generic(foo, type-name: association, ..., default: association) performs a + * comparison against the foo type (not the qualified type). + * Do not use the const keyword in the type-name as it will not match the + * unqualified type of foo. + */ +#define __unconst_integer_type_cases(type) \ + unsigned type: (unsigned type)0, \ + signed type: (signed type)0 + +#define __unconst_integer_typeof(x) typeof( \ + _Generic((x), \ + char: (char)0, \ + __unconst_integer_type_cases(char), \ + __unconst_integer_type_cases(short), \ + __unconst_integer_type_cases(int), \ + __unconst_integer_type_cases(long), \ + __unconst_integer_type_cases(long long), \ + default: (x))) + +/* + * Do not check the array parameter using __must_be_array(). + * In the following legit use-case where the "array" passed is a simple pointer, + * __must_be_array() will return a failure. + * --- 8< --- + * int *buff + * ... + * min = min_array(buff, nb_items); + * --- 8< --- + * + * The first typeof(&(array)[0]) is needed in order to support arrays of both + * 'int *buff' and 'int buf[N]' types. + * + * The array can be an array of const items. + * typeof() keeps the const qualifier. Use __unconst_typeof() in order to + * discard the const qualifier for the __element variable. + */ +#define __minmax_array(op, array, len) ({ \ + typeof(&(array)[0]) __array = (array); \ + typeof(len) __len = (len); \ + __unconst_integer_typeof(__array[0]) __element = __array[--__len]; \ + while (__len--) \ + __element = op(__element, __array[__len]); \ + __element; }) + +/** + * min_array - return minimum of values present in an array + * @array: array + * @len: array length + * + * Note that @len must not be zero (empty array). + */ +#define min_array(array, len) __minmax_array(min, array, len) + +/** + * max_array - return maximum of values present in an array + * @array: array + * @len: array length + * + * Note that @len must not be zero (empty array). + */ +#define max_array(array, len) __minmax_array(max, array, len) + /** * clamp_t - return a value clamped to a given range using a given type * @type: the type of variable to use