From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.smtpout.orange.fr (smtp-27.smtpout.orange.fr [80.12.242.27]) by sourceware.org (Postfix) with ESMTPS id 662833858C53 for ; Fri, 25 Aug 2023 13:07:30 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 662833858C53 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=jacob.remcomp.fr Authentication-Results: sourceware.org; spf=none smtp.mailfrom=jacob.remcomp.fr Received: from smtpclient.apple ([90.22.252.13]) by smtp.orange.fr with ESMTPS id ZWXAqZV7RLJHlZWXAqNKX1; Fri, 25 Aug 2023 15:07:29 +0200 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=wanadoo.fr; s=t20230301; t=1692968849; bh=beohYQxGlIVJ8aqBFtOku2KjAX0Td5VnAu78zjiqBPE=; h=Subject:From:In-Reply-To:Date:Cc:References:To; b=LPXxx00uou1QIqaeuiQ1vwQrCNg87gH9DuzXph96HzlSgxrFh1at8NH2AJbBI2Yg8 Jp8zunZe7gyb4TtrzqryylSEg44YK90T3K4mnYhhGcrSzAG1S2qf+XgmeWI2XpxsYa ItBt+LJG1wT9V8mSWg5AJHUCpWt9K7D+s8xYKkNpIyedzxeAdK+MjZL40dvBefXSqe fctB038G5rhIGGT8VIGqVSOL9h/I6OHgH+BrzPMYDPoWdwzepvI79nNJHHQltHQrOA 4msNDbCLfFtoZDpmR15w+dpCkkwI6DadiO4qa7eq8rw4IiJGojEdE9K7wM/6aMNlbr 5Z5S4PbtVru1w== X-ME-Helo: smtpclient.apple X-ME-Date: Fri, 25 Aug 2023 15:07:29 +0200 X-ME-IP: 90.22.252.13 Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3731.600.7\)) Subject: Re: P.S. Follow up to my last post From: jacob navia In-Reply-To: <7ae0d3c7-d785-d693-03c1-989e399db7c8@suse.com> Date: Fri, 25 Aug 2023 15:07:18 +0200 Cc: binutils@sourceware.org Content-Transfer-Encoding: quoted-printable Message-Id: <10D53FD6-B509-4F68-A06D-2EC17F99AC43@jacob.remcomp.fr> References: <1140E4A3-B227-4824-B4D1-88A95910C0CC@jacob.remcomp.fr> <7ae0d3c7-d785-d693-03c1-989e399db7c8@suse.com> To: Jan Beulich X-Mailer: Apple Mail (2.3731.600.7) X-Spam-Status: No, score=-1.4 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,FORGED_SPF_HELO,RCVD_IN_DNSWL_NONE,SPF_HELO_PASS,SPF_NONE,TXREP autolearn=no autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: OK, there is no bug, I didn=E2=80=99t expect anything else. SO: To use all the instruction of the processor he/she is running on, the = user should: 1)Be aware that gcc doesn=E2=80=99t see crucial instructions of the = processor by verifying its assembler output. 2) Be aware that there is an (undocumented) option -march=E2=80=A6 that = will enable the assembler and the compiler to generate all the = instructions of the current processor. Well, there is NO BUG! This is by design then. Thank you very much. Jacob > Le 25 ao=C3=BBt 2023 =C3=A0 14:00, Jan Beulich a = =C3=A9crit : >=20 > On 25.08.2023 13:52, jacob navia wrote: >> The lack of the Ebb instructions is CRUCIAL for performance when = accessing tables / arrays! >> This instructions allow to combine an addition and a shift by 1, 2 or = 3, to access tables of shorts, ints or doubles. >> This speeds up the access to tables enormously and would allow gcc to = generate much better code. >=20 > Since you're writing to binutils@, you may want to also mention what = gas > bug you think you see. So far (also in the other mail) you've talked = of > only gcc. If you meant to say that like in gcc you need to enable use = of > the instructions in gas, then yes, that's the way the RISC-V assembler > works (like e.g. also the PPC one, but unlike e.g. the x86 one). >=20 > Jan