From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qt1-x82a.google.com (mail-qt1-x82a.google.com [IPv6:2607:f8b0:4864:20::82a]) by sourceware.org (Postfix) with ESMTPS id 4B063384BC3F for ; Thu, 20 Oct 2022 17:04:26 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 4B063384BC3F Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=gmail.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=gmail.com Received: by mail-qt1-x82a.google.com with SMTP id cr19so37396qtb.0 for ; Thu, 20 Oct 2022 10:04:26 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=RPn0TWzRPVpQr/EXvCTd2y6hS31gN5d+/ZCMkXoMrfg=; b=ZlO1R71Bh0Df2xjg14XkVqsMzqXSsar4SwLfDDMZLW81a3gzgMamgRgAZgcZYGYmKq aJWfdhwRPycI5ri6EdCb9nr3nlS9xFTnubavyXL6fcq1CH0lmPML1hjWVXqDiu2DmRoT 6Qc5j7NgS9D6Q+hIjh4jw+X0jbXep8mpOXWnKUk/z1fc5ltIxyVAQ8hXkap6YEWjVDtb CSTLxrdmfQ2SudXl7NRheWK0epNA7MNYfGlIRICHbxlGUaRMZu8js5gpNRg9R/X+HZfN AkHwy14vP3oIywRmmzKcZBBZWphoqQWN351weME+Sg0/DGiJkzfX9YYc9oWQkMz/fN+w 2Cdw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=RPn0TWzRPVpQr/EXvCTd2y6hS31gN5d+/ZCMkXoMrfg=; b=u1WEIL9nMkm7tdFlNGtm6zq2XnvmWqGuPvGo1tDz9TQYPF1YQF7Ahb6YPrpsKy/F2T yaxsjfHh+T8c1HlrSxZL1q+dOa9uwqbXC2dpfjEaeLtAXoLzuMTn25vNRUCQeiZLKwds L8kh8K3xPX0aeHJaOuQmhoYtyoycpG6xltKyyfaUyNuEwFnFtp8/peD0rfCUp87sDoku 6yv/PQrN+/1k7ir7ZGMl7Hg+uJCY/vlYtS98BzmvdoLEaFlX1/DQQqEjhtcUPYEIvgOd 1CkDenFfxdL8mTre6yNp5SX6Opzhg+R9XCASS7rNotOTQSir+erA1TKRXqPO3RTxhKRH 7X2g== X-Gm-Message-State: ACrzQf0NgoDA+xULIM9CdbHPvhe5Ghlj2Aho7yZmIwmZyz2/gUji9ADR tJpz9AFYW6NWf/wEO1N0U8aUt9gkOUGoKsCJEhzAAqHp X-Google-Smtp-Source: AMsMyM4+1Yz3HqKyeVyBLmNEvJuHhrJ5gclUxpLDlgeva/cyWPmUWBB4+U2VU013due6l1yZOVTGTgGPwAWWOxcd0BI= X-Received: by 2002:a05:620a:2552:b0:6ca:bf8f:4d27 with SMTP id s18-20020a05620a255200b006cabf8f4d27mr9988267qko.383.1666285454889; Thu, 20 Oct 2022 10:04:14 -0700 (PDT) MIME-Version: 1.0 References: <20221020021338.3394281-1-goldstein.w.n@gmail.com> <20221020021338.3394281-4-goldstein.w.n@gmail.com> In-Reply-To: <20221020021338.3394281-4-goldstein.w.n@gmail.com> From: "H.J. Lu" Date: Thu, 20 Oct 2022 10:03:39 -0700 Message-ID: Subject: Re: [PATCH v1 4/4] x86: Use `testb` for FSRM check in memmove-vec-unaligned-erms To: Noah Goldstein Cc: libc-alpha@sourceware.org, carlos@systemhalted.org Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-3023.7 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM,GIT_PATCH_0,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 List-Id: On Wed, Oct 19, 2022 at 7:14 PM Noah Goldstein wrote: > > `testb` saves a bit of code size is the imm-operand can be encoded > 1-bytes. > > Tested on x86-64. > --- > sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S b/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S > index 5b758cae5e..f6d7f3e88b 100644 > --- a/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S > +++ b/sysdeps/x86_64/multiarch/memmove-vec-unaligned-erms.S > @@ -616,7 +616,11 @@ L(movsb): > jae L(large_memcpy_2x_check) > # if AVOID_SHORT_DISTANCE_REP_MOVSB || ALIGN_MOVSB > /* Only avoid short movsb if CPU has FSRM. */ > +# if X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB < 256 > + testb $X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB, __x86_string_control(%rip) > +# else > testl $X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB, __x86_string_control(%rip) > +# endif > jz L(skip_short_movsb_check) > # if AVOID_SHORT_DISTANCE_REP_MOVSB > /* Avoid "rep movsb" if RCX, the distance between source and > -- > 2.34.1 > LGTM. Thanks. -- H.J.