From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by inbox.dpdk.org (Postfix) with ESMTP id C920FA00C2; Wed, 23 Nov 2022 23:14:57 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 7C0A642DAE; Wed, 23 Nov 2022 23:14:55 +0100 (CET) Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by mails.dpdk.org (Postfix) with ESMTP id 5980942DA9 for ; Wed, 23 Nov 2022 23:14:53 +0100 (CET) Received: by linux.microsoft.com (Postfix, from userid 1086) id 8A5A220B83C2; Wed, 23 Nov 2022 14:14:52 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 8A5A220B83C2 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1669241692; bh=dUG2lrQsCT8l01AEIVtNeEp90jAmY60yp1geVthNGzI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=paqB24eAF9bcwNumVK5k+YhZkpC6VxVD2p5O7WdhRxS0Ba8NPgoRpLv9XWG05PHFO SO2iA1XvoAlG8vpmVg71p8dnljD2QD6HKh5Y/JE8bzEme36V8pQQz+et7mJJRB0oeq Xb99t1ebJQpHCLHnBMmQGZv3Oh7EO1xOwFT/muVc= From: Tyler Retzlaff To: dev@dpdk.org Cc: Tyler Retzlaff Subject: [PATCH 1/2] eal: provide leading and trailing zero bit count abstraction Date: Wed, 23 Nov 2022 14:14:46 -0800 Message-Id: <1669241687-18810-2-git-send-email-roretzla@linux.microsoft.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1669241687-18810-1-git-send-email-roretzla@linux.microsoft.com> References: <1669241687-18810-1-git-send-email-roretzla@linux.microsoft.com> X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Provide an abstraction for leading and trailing zero bit counting functions to hide compiler specific intrinsics and builtins. Signed-off-by: Tyler Retzlaff --- lib/eal/include/meson.build | 1 + lib/eal/include/rte_bitcount.h | 257 +++++++++++++++++++++++++++++++++++++++++ 2 files changed, 258 insertions(+) create mode 100644 lib/eal/include/rte_bitcount.h diff --git a/lib/eal/include/meson.build b/lib/eal/include/meson.build index cfcd40a..8ff1d65 100644 --- a/lib/eal/include/meson.build +++ b/lib/eal/include/meson.build @@ -5,6 +5,7 @@ includes += include_directories('.') headers += files( 'rte_alarm.h', + 'rte_bitcount.h', 'rte_bitmap.h', 'rte_bitops.h', 'rte_branch_prediction.h', diff --git a/lib/eal/include/rte_bitcount.h b/lib/eal/include/rte_bitcount.h new file mode 100644 index 0000000..2f4dd38 --- /dev/null +++ b/lib/eal/include/rte_bitcount.h @@ -0,0 +1,257 @@ +/* SPDX-License-Identifier: BSD-3-Clause + * Copyright (C) 2022 Microsoft Corporation + */ + +#ifndef EAL_BITCOUNT_H +#define EAL_BITCOUNT_H + +#include + +#ifdef RTE_TOOLCHAIN_MSVC + +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the count of leading 0-bits in v. + * + * @param v + * The value. + * @return + * The count of leading zero bits. + */ +__rte_experimental +static inline unsigned +rte_clz(unsigned int v) +{ + unsigned long rv; + + (void)_BitScanReverse(&rv, v); + + return (unsigned)rv; +} + +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the count of leading 0-bits in v. + * + * @param v + * The value. + * @return + * The count of leading zero bits. + */ +__rte_experimental +static inline unsigned +rte_clzl(unsigned long v) +{ + unsigned long rv; + + (void)_BitScanReverse(&rv, v); + + return (unsigned)rv; +} + +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the count of leading 0-bits in v. + * + * @param v + * The value. + * @return + * The count of leading zero bits. + */ +__rte_experimental +static inline unsigned +rte_clzll(unsigned long long v) +{ + unsigned long rv; + + (void)_BitScanReverse64(&rv, v); + + return (unsigned)rv; +} + +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the count of trailing 0-bits in v. + * + * @param v + * The value. + * @return + * The count of trailing zero bits. + */ +__rte_experimental +static inline unsigned +rte_ctz(unsigned int v) +{ + unsigned long rv; + + (void)_BitScanForward(&rv, v); + + return (unsigned)rv; +} + +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the count of trailing 0-bits in v. + * + * @param v + * The value. + * @return + * The count of trailing zero bits. + */ +__rte_experimental +static inline unsigned +rte_ctzl(unsigned long v) +{ + unsigned long rv; + + (void)_BitScanForward(&rv, v); + + return (unsigned)rv; +} + +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the count of trailing 0-bits in v. + * + * @param v + * The value. + * @return + * The count of trailing zero bits. + */ +__rte_experimental +static inline unsigned +rte_ctzll(unsigned long long v) +{ + unsigned long rv; + + (void)_BitScanForward64(&rv, v); + + return (unsigned)rv; +} + +#else + +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the count of leading 0-bits in v. + * + * @param v + * The value. + * @return + * The count of leading zero bits. + */ +__rte_experimental +static inline unsigned +rte_clz(unsigned int v) +{ + return (unsigned)__builtin_clz(v); +} + +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the count of leading 0-bits in v. + * + * @param v + * The value. + * @return + * The count of leading zero bits. + */ +__rte_experimental +static inline unsigned +rte_clzl(unsigned long v) +{ + return (unsigned)__builtin_clzl(v); +} + +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the count of leading 0-bits in v. + * + * @param v + * The value. + * @return + * The count of leading zero bits. + */ +__rte_experimental +static inline unsigned +rte_clzll(unsigned long v) +{ + return (unsigned)__builtin_clzll(v); +} + +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the count of trailing 0-bits in v. + * + * @param v + * The value. + * @return + * The count of trailing zero bits. + */ +__rte_experimental +static inline unsigned +rte_ctz(unsigned int v) +{ + return (unsigned)__builtin_ctz(v); +} + +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the count of trailing 0-bits in v. + * + * @param v + * The value. + * @return + * The count of trailing zero bits. + */ +__rte_experimental +static inline unsigned +rte_ctzl(unsigned long v) +{ + return (unsigned)__builtin_ctzl(v); +} + +/** + * @warning + * @b EXPERIMENTAL: this API may change, or be removed, without prior notice + * + * Get the count of trailing 0-bits in v. + * + * @param v + * The value. + * @return + * The count of trailing zero bits. + */ +__rte_experimental +static inline unsigned +rte_ctzll(unsigned long v) +{ + return (unsigned)__builtin_ctzll(v); +} + +#endif + +#endif /* EAL_BITCOUNT_H */ + -- 1.8.3.1