From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.3 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C7FAEC433E1 for ; Fri, 14 Aug 2020 18:37:41 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 901A820774 for ; Fri, 14 Aug 2020 18:37:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=linaro.org header.i=@linaro.org header.b="CSSJKKfy" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 901A820774 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linaro.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:49610 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1k6eaC-0003oh-RR for qemu-devel@archiver.kernel.org; Fri, 14 Aug 2020 14:37:40 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:42852) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1k6eZY-0003La-Ew for qemu-devel@nongnu.org; Fri, 14 Aug 2020 14:37:00 -0400 Received: from mail-pj1-x102f.google.com ([2607:f8b0:4864:20::102f]:53677) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1k6eZU-0007hP-Il for qemu-devel@nongnu.org; Fri, 14 Aug 2020 14:36:59 -0400 Received: by mail-pj1-x102f.google.com with SMTP id l60so4812959pjb.3 for ; Fri, 14 Aug 2020 11:36:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=subject:to:cc:references:from:message-id:date:user-agent :mime-version:in-reply-to:content-language:content-transfer-encoding; bh=mSyGCQ00UyCgU4W9lEQIrAQfxGRZDKKKHrtU9PhMcIQ=; b=CSSJKKfy+sonqbtGFLnLCNeBbrSCw7u9HMPegawyNa4ju/wtj18SKQr71AeFIQSkwY WlRmAVDYf7QAJgNuIgIxe93VRu4vvxNIFzJ62+iV/VwKC6AR+CB26ZUTXgDk3lO5ZUS6 M3m2YlCSNrYmsk3bzjZnP7USMDQ4wjBgKxJX7vnMmjFrwI4Evzh4kcQ+vKSecthOpsEj eWR4c2Zy9ZSyoNUXvDT2O3FWN0IR+ohDCvaxnWk2XA26tEGN+IUJevEJ5GCQYNBr0mDq YrXNzoGKyBA2WbtxDuVtYq565BTh65nHP7cLK2QJFgD/5WhoNnvaHU9f/6yEYeJFBW6K AD/Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:to:cc:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-language :content-transfer-encoding; bh=mSyGCQ00UyCgU4W9lEQIrAQfxGRZDKKKHrtU9PhMcIQ=; b=TK/sH9zeH63gZagnctFkqepPCDbEjqd7veDvkrssr2NtShQjhE1Si2bt9/bv8vCHoR H3FbtJDniLgdcKm5nnbUGs5BOxZeKG1w4tBPv2PFrpJqEuo0Qf359CUUrja9mw78X+XB 5WbmRywb2IVViSx9OZGPGvxjxeMiL/9mrPFBObjK7Kr2X0+KJU4PTsFL6I7wA2NymOfA nUmD4PDDqZjAjQFY6+fJh1+JFG+N1AonjbTKCHXOCroOumq1FLWDRvgCUcuTZ3VRVvxr q9ATcldd5XFEu4JdZHkRpkj1RDNpexxCW0sbcn4FygLxsq0fZ3OfJKsHdQPeN4XNw13B g+7Q== X-Gm-Message-State: AOAM532FkkBuVM9S+Hqr72FwfPmz6e00tgAqMa6CsZ2FX5AT/PePu4/1 DGwhwz9aam8wwpk5B6IcAz35ag== X-Google-Smtp-Source: ABdhPJyZLCyL2BtMWKO3xuiCXoArtbr1UhQmM/7Dh3ImiZJHn6KM0/KKC75b/GBGVAuobIHZ3tG/QQ== X-Received: by 2002:a17:90b:803:: with SMTP id bk3mr3324828pjb.57.1597430214965; Fri, 14 Aug 2020 11:36:54 -0700 (PDT) Received: from [192.168.1.11] ([71.212.141.89]) by smtp.gmail.com with ESMTPSA id d128sm10192297pfa.24.2020.08.14.11.36.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 14 Aug 2020 11:36:54 -0700 (PDT) Subject: Re: [RFC v3 26/71] target/riscv: rvv-1.0: update vext_max_elems() for load/store insns To: Frank Chang References: <20200806104709.13235-1-frank.chang@sifive.com> <20200806104709.13235-27-frank.chang@sifive.com> <90f01984-54a4-2a56-c52f-d1f4332b39d4@linaro.org> From: Richard Henderson Message-ID: <5706a1ca-1dd9-22cd-08ce-c70780111bfc@linaro.org> Date: Fri, 14 Aug 2020 11:36:52 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=2607:f8b0:4864:20::102f; envelope-from=richard.henderson@linaro.org; helo=mail-pj1-x102f.google.com X-detected-operating-system: by eggs.gnu.org: No matching host in p0f cache. That's all we know. X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: "open list:RISC-V" , Sagar Karandikar , Bastian Koppelmann , "qemu-devel@nongnu.org Developers" , Alistair Francis , Palmer Dabbelt Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On 8/13/20 7:48 PM, Frank Chang wrote: > esz is passed from e.g. GEN_VEXT_LD_STRIDE() macro: > >> #define GEN_VEXT_LD_STRIDE(NAME, ETYPE, LOAD_FN)        \ >> void HELPER(NAME)(void *vd, void * v0, target_ulong base,  \ >>                   target_ulong stride, CPURISCVState *env, \ >>                   uint32_t desc)                           \ >> {                                                          \ >>     uint32_t vm = vext_vm(desc);                           \ >>     vext_ldst_stride(vd, v0, base, stride, env, desc, vm, LOAD_FN, \ >>                      sizeof(ETYPE), GETPC(), MMU_DATA_LOAD);       \ >> } >> >> GEN_VEXT_LD_STRIDE(vlse8_v,  int8_t,  lde_b) > > which is calculated by sizeof(ETYPE), so the results would be: 1, 2, 4, 8. > and vext_max_elems() is called by e.g. vext_ldst_stride(): Ah, yes. >> uint32_t max_elems = vext_max_elems(desc, esz); > > I can add another parameter to the macro and pass the hard-coded log2(esz) number > if it's the better way instead of using ctzl(). > Or if there's another approach to get the log2(esz) number more elegantly? Using ctzl(sizeof(type)) in the GEN_VEXT_LD_STRIDE macro will work well. This will be constant folded by the compiler. r~