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 06C3B45DBB; Wed, 27 Nov 2024 23:58:12 +0100 (CET) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id DBAEA402E3; Wed, 27 Nov 2024 23:58:11 +0100 (CET) Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by mails.dpdk.org (Postfix) with ESMTP id 902864029C for ; Wed, 27 Nov 2024 23:58:10 +0100 (CET) Received: by linux.microsoft.com (Postfix, from userid 1213) id B99F52053045; Wed, 27 Nov 2024 14:58:09 -0800 (PST) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com B99F52053045 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1732748289; bh=H+7Sqg8BW61xyYvnNah6mVGYK4e6BUgOrVfPvVvj/is=; h=From:To:Cc:Subject:Date:From; b=EhpwPkHPuxiUqzIbLJ5M/CKn/08MZu5DcVoH49Ry+GpLHEoYhtI09xJQylg78gChX /d3yAR+LbKxAsgfa6WoEe6Gth04MtV++1o+507srE7Oog92940fRy76kv1O89V9W0D 1n6i7Hf7vKzHsPuOBaGnAuYm2m+R6oM0ywkDO+rs= From: Andre Muezerie To: Yipeng Wang , Sameh Gobriel , Bruce Richardson , Vladimir Medvedkin Cc: dev@dpdk.org, Andre Muezerie Subject: [PATCH 1/2] lib/hash: initialize __m128i data type in a portable way Date: Wed, 27 Nov 2024 14:57:57 -0800 Message-Id: <1732748278-14796-1-git-send-email-andremue@linux.microsoft.com> X-Mailer: git-send-email 1.8.3.1 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 The mechanism used to initialize an __m128i data type in rte_thash.h is non-portable and MSVC does not like it. It clearly is not doing what is desired: ..\lib\hash\rte_thash.h(38): warning C4305: 'initializing': truncation from 'unsigned __int64' to 'char' ..\lib\hash\rte_thash.h(38): warning C4305: 'initializing': truncation from 'unsigned __int64' to 'char' A more portable approach is to use compiler intrinsics to perform the initialization. This patch uses a single compiler intrinsic to initialize the data type using a sequence of 16 bytes stored in memory. There should be no perf degradation due to this change. Signed-off-by: Andre Muezerie --- lib/hash/rte_thash.h | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/lib/hash/rte_thash.h b/lib/hash/rte_thash.h index c0af5968df..3512639792 100644 --- a/lib/hash/rte_thash.h +++ b/lib/hash/rte_thash.h @@ -34,8 +34,9 @@ extern "C" { /* Byte swap mask used for converting IPv6 address * 4-byte chunks to CPU byte order */ -static const __m128i rte_thash_ipv6_bswap_mask = { - 0x0405060700010203ULL, 0x0C0D0E0F08090A0BULL}; +static const uint8_t rte_thash_ipv6_bswap_mask[] = { + 0x03, 0x02, 0x01, 0x00, 0x07, 0x06, 0x05, 0x04, + 0x0B, 0x0A, 0x09, 0x08, 0x0F, 0x0E, 0x0D, 0x0C}; #endif /** @@ -152,12 +153,14 @@ rte_thash_load_v6_addrs(const struct rte_ipv6_hdr *orig, union rte_thash_tuple *targ) { #ifdef RTE_ARCH_X86 + const __m128i ipv6_bswap_mask = + _mm_loadu_si128((const __m128i*)&rte_thash_ipv6_bswap_mask); __m128i ipv6 = _mm_loadu_si128((const __m128i *)&orig->src_addr); *(__m128i *)&targ->v6.src_addr = - _mm_shuffle_epi8(ipv6, rte_thash_ipv6_bswap_mask); + _mm_shuffle_epi8(ipv6, ipv6_bswap_mask); ipv6 = _mm_loadu_si128((const __m128i *)&orig->dst_addr); *(__m128i *)&targ->v6.dst_addr = - _mm_shuffle_epi8(ipv6, rte_thash_ipv6_bswap_mask); + _mm_shuffle_epi8(ipv6, ipv6_bswap_mask); #elif defined(__ARM_NEON) uint8x16_t ipv6 = vld1q_u8(orig->src_addr.a); vst1q_u8(targ->v6.src_addr.a, vrev32q_u8(ipv6)); -- 2.34.1