From patchwork Wed Feb 1 17:03:54 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella Netto X-Patchwork-Id: 64113 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 86EBC3858020 for ; Wed, 1 Feb 2023 17:10:27 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 86EBC3858020 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1675271427; bh=eaPuAUW6u9EzarB15eu0qKq3XLrPgGatZ3LrJa3nfQo=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=e4WeGZ54Dzi2T5H3YIvGJvxdWwenNVpT1XMf4h2fnpWhonDVnFEpwsRDlWI2zIHuC qRvThceoVcf7PpjlxFlCfxhIPqFiZq7PZ6xlkBN/1r8rxmEAR1ws01YE4IkWKafGoE gYwh/lMb5sTHCJFOdmK6x3OZeWvL4zwlo1F0y07Q= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-oa1-x31.google.com (mail-oa1-x31.google.com [IPv6:2001:4860:4864:20::31]) by sourceware.org (Postfix) with ESMTPS id 344333857C4F for ; Wed, 1 Feb 2023 17:04:57 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 344333857C4F Received: by mail-oa1-x31.google.com with SMTP id 586e51a60fabf-16346330067so24358642fac.3 for ; Wed, 01 Feb 2023 09:04:57 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=eaPuAUW6u9EzarB15eu0qKq3XLrPgGatZ3LrJa3nfQo=; b=VAq42Ro41ckcs5vJQdzvYInJHlecigy873OuNpcKIFImwNbEIl8+T1Jv9BglqjZXju Dc5nWAVSK9RNGmdp3VIz5HsAJPGo5MMEJZq3Y/5WAEitJq8OoiVD872tkjr2v0THMzCA vZ1thSlWGlm8bL/wan7cjwg//CzQa8BcKTab4NasFr4NZAxU1V30lUWfg/POamz6grlm pPZNewtGbS425usObUSk1PFoqjAmV6623lxBH0STkH9RBuKPaH9zctBtWUoJTKuXclXQ qejod7Px7YGoAyAz/biGiS/UKCzRbVtcaKhOMtYsczIt9dzhHrCkExWKkpwvm/nhQzMc XtPg== X-Gm-Message-State: AO0yUKWTp83fiTzsfdOn17UGJp6jZe9cEYZb8KqL/oXanEcoo9hM9E8r 2kRri7xS0DUjSeXrFVXbtSZM9OaZzHp06BqFdB8= X-Google-Smtp-Source: AK7set/nSg6UqC4fs4FsHfknu2aUp8JGgO4/YjBuBz+F9qF6jlpGklbK4zwU1iBOoCPkTVoFdAZKiA== X-Received: by 2002:a05:6870:c69a:b0:15b:9ee2:4c36 with SMTP id cv26-20020a056870c69a00b0015b9ee24c36mr1788517oab.35.1675271095988; Wed, 01 Feb 2023 09:04:55 -0800 (PST) Received: from mandiga.. ([2804:1b3:a7c2:1887:d2ed:98c2:d2cc:bf06]) by smtp.gmail.com with ESMTPSA id b17-20020a056830311100b006863ccbf067sm8077090ots.74.2023.02.01.09.04.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 01 Feb 2023 09:04:55 -0800 (PST) To: libc-alpha@sourceware.org, Richard Henderson , Noah Goldstein , Jeff Law , Xi Ruoyao Subject: [PATCH v11 17/29] arm: Add string-fza.h Date: Wed, 1 Feb 2023 14:03:54 -0300 Message-Id: <20230201170406.303978-18-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230201170406.303978-1-adhemerval.zanella@linaro.org> References: <20230201170406.303978-1-adhemerval.zanella@linaro.org> MIME-Version: 1.0 X-Spam-Status: No, score=-12.8 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Adhemerval Zanella via Libc-alpha From: Adhemerval Zanella Netto Reply-To: Adhemerval Zanella Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Sender: "Libc-alpha" From: Richard Henderson While arm has the more important string functions in assembly, there are still a few generic routines used. Use the UQSUB8 insn for testing of zeros. Checked on armv7-linux-gnueabihf --- sysdeps/arm/armv6t2/string-fza.h | 68 ++++++++++++++++++++++++++++++++ 1 file changed, 68 insertions(+) create mode 100644 sysdeps/arm/armv6t2/string-fza.h diff --git a/sysdeps/arm/armv6t2/string-fza.h b/sysdeps/arm/armv6t2/string-fza.h new file mode 100644 index 0000000000..50afaba038 --- /dev/null +++ b/sysdeps/arm/armv6t2/string-fza.h @@ -0,0 +1,68 @@ +/* Zero byte detection; basics. ARM version. + Copyright (C) 2023 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#ifndef _STRING_FZA_H +#define _STRING_FZA_H 1 + +#include +#include + +/* The functions return a byte mask. */ +typedef op_t find_t; + +/* This function returns at least one bit set within every byte + of X that is zero. */ +static __always_inline find_t +find_zero_all (op_t x) +{ + /* Use unsigned saturated subtraction from 1 in each byte. + That leaves 1 for every byte that was zero. */ + op_t ones = repeat_bytes (0x01); + return __builtin_arm_uqsub8 (ones, x); +} + +/* Identify bytes that are equal between X1 and X2. */ +static __always_inline find_t +find_eq_all (op_t x1, op_t x2) +{ + return find_zero_all (x1 ^ x2); +} + +/* Identify zero bytes in X1 or equality between X1 and X2. */ +static __always_inline find_t +find_zero_eq_all (op_t x1, op_t x2) +{ + return find_zero_all (x1) | find_zero_all (x1 ^ x2); +} + +/* Identify zero bytes in X1 or inequality between X1 and X2. */ +static __always_inline find_t +find_zero_ne_all (op_t x1, op_t x2) +{ + /* Make use of the fact that we'll already have ONES in a register. */ + op_t ones = repeat_bytes (0x01); + return find_zero_all (x1) | (find_zero_all (x1 ^ x2) ^ ones); +} + +/* Define the "inexact" versions in terms of the exact versions. */ +#define find_zero_low find_zero_all +#define find_eq_low find_eq_all +#define find_zero_eq_low find_zero_eq_all +#define find_zero_ne_low find_zero_ne_all + +#endif /* _STRING_FZA_H */