From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-qk1-x736.google.com (mail-qk1-x736.google.com [IPv6:2607:f8b0:4864:20::736]) by sourceware.org (Postfix) with ESMTPS id E13DC384AB48 for ; Tue, 16 Apr 2024 14:55:40 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org E13DC384AB48 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=bluespec.com Authentication-Results: sourceware.org; spf=fail smtp.mailfrom=bluespec.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org E13DC384AB48 Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=2607:f8b0:4864:20::736 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1713279344; cv=none; b=XzS0cmKVPoDrgiGiR64uJPzDUVnWiMmZwj1U5yfEZSboHGX46z3igacYvDRq7uvKuJtP9ya3O5SJlM79JxNnrlZ3Yhw5TsDZEXj+CwPJCnH55YgvRzJDcxmlxTsmwufoQAFG+Zsx7bW7MDJkrAbfChHkOvJxiZACt57unQ5kalQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1713279344; c=relaxed/simple; bh=1H0RN1UTbZtain98vGUCc5R6efjFzCy7uMkIQBYla7A=; h=DKIM-Signature:Date:From:To:Subject:Message-ID:MIME-Version; b=jQEgzwFQRIDaUzsIHeQZ7caasJL7FrygUqCy1Mw8Gjl2/d5xpB5oVHfjQ+kzQl42WFSdEKB65XqyUGNqHl1eOoMouk8pEBeIhBF5JeF0BO9arjbu4D57sDf59uy6nl/fQ/noJbaSOX5IqTtMeQ11ooSMX3OYbge2o15dxI95O3Y= ARC-Authentication-Results: i=1; server2.sourceware.org Received: by mail-qk1-x736.google.com with SMTP id af79cd13be357-78ee82e7062so151481985a.3 for ; Tue, 16 Apr 2024 07:55:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bluespec-com.20230601.gappssmtp.com; s=20230601; t=1713279340; x=1713884140; darn=sourceware.org; h=in-reply-to:content-disposition:mime-version:references :mail-followup-to:message-id:subject:cc:to:from:date:from:to:cc :subject:date:message-id:reply-to; bh=ASf0vHlwAtshZ2OaZwCQ1ILi2KgNLsSeGHkl9Clpsjw=; b=rTWYIUxAsniZlEamahJQDJ4Wp2pWEEbkGgbrPuKfLtKbQMANW+vi6WFrA9Jtjo2b4W EIaVRSeIm8aTUWY1JlQJFpyN8CbcKNsWIQqqelhsuS7RijgdlyMS/x35l0Ycb/KZ/boo qsUDxXHTKtmomwnYX8fHauuDiLSy7rU151r/0YAEernwtqalhI4qAkWlwbfu1q4vTNzF FaejwdoK828PZz4DEXVj/J7i+2WeiA8/w74QIdOYA/DD1ZX5/iQFrL1l7HRJu7hR8mol 4NolswWb+Fhh1ZrY4+30mvaK3+4CHDN650Fyt2jyuz4Mi+FVWcWwUN7StV9YlHwGDUT9 WF+Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1713279340; x=1713884140; h=in-reply-to:content-disposition:mime-version:references :mail-followup-to:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=ASf0vHlwAtshZ2OaZwCQ1ILi2KgNLsSeGHkl9Clpsjw=; b=k8xv2AYSgEwCB71ykagPTbSyY8nWokfPujvTGdb/qrGoNq2SUO7sQI5kITiuauWVPq Wg6Lcy9NgVnmQHS4jksIRMtF+T6p6llaLdczJ6Y+63P7/TmvJJu1SgI3brPyp6GUgm2I SkNriIeONBV+u77z4y/k/Jt69GY/E49rwzVEisLYtoiU/V4Ty6fCxZt6TEhKpF8UeLSO xWTipbuHhXzlWpiFC6fXb8isNWNNDMgcRNEIILn8lhExbPkLSX3WW9t0+Avh2En4H8Zq YtkbeuernAaKDRB/xnLZkA83pqM0jV+9SfVDsYvcYdoboMkXb9niHHleMVa8XL9zbXyf o1oA== X-Gm-Message-State: AOJu0Yx2CgHyDHBENfM0AGyPP44j0d76wg7LchH6AQOBFYNAkEohbQD8 AgOCQfsG7gY7l+tiqDU5AAXYrGBL1l/GcIF7qL9R4Ndop9MG+que43dRaONqgkihCZ9XNFNY87P K X-Google-Smtp-Source: AGHT+IHOcmxMcG41Z/BP8S3C8s4q5sWvLacpO6AoE9w04lBYyrFnur134Q/5UHHK+5Mjeenk9YM/5g== X-Received: by 2002:a05:620a:1594:b0:78e:cd30:c274 with SMTP id d20-20020a05620a159400b0078ecd30c274mr13182157qkk.19.1713279340194; Tue, 16 Apr 2024 07:55:40 -0700 (PDT) Received: from localhost.localdomain ([181.214.94.204]) by smtp.gmail.com with ESMTPSA id c9-20020a05620a200900b0078d7213de13sm7512138qka.136.2024.04.16.07.55.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 16 Apr 2024 07:55:39 -0700 (PDT) Date: Tue, 16 Apr 2024 10:55:38 -0400 From: Darius Rad To: Palmer Dabbelt Cc: libc-alpha@sourceware.org Subject: Re: [RFC] build-many-glibcs: Add a rv64gcbv-on-rv64gc/lp64d sub-variant Message-ID: Mail-Followup-To: Palmer Dabbelt , libc-alpha@sourceware.org References: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: X-Spam-Status: No, score=-4.6 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,JMQ_SPF_NEUTRAL,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_NEUTRAL,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: On Mon, Apr 15, 2024 at 02:36:59PM -0700, Palmer Dabbelt wrote: > On Mon, 15 Apr 2024 13:24:14 PDT (-0700), Darius Rad wrote: > > Is this really lp64d? > > I guess that depend on what you mean by "ABI". Passing `-march=rv64gv > -mabi=lp64d` will result in binaries that require the V extension to run, > but can be linked with any other binary that is compiled with `-mabi=lp64d`. > It's essentially the same as `-march=rv64g -mabi=lp64`, except for vector > instead of float. > Got it. I thought that might be the case, but wasn't sure if the vector calling convention leaked in with the arch switch only (and not the abi). > > What is the status of the vector ABI? > > We don't have a global vector ABI switch for GCC (ie, `-mabi=lp64dv`) and we > decided not to put on in for GCC-14. We've essentially got all the > machinery there for it, as we've got the vector calling convention > attribute, but that came in pretty late and we decided it'd be better to > wait. > > I don't see any reason it'd miss GCC-15, but no promises as there's not even > a patch on the lists yet... > Understood. Though when this hits, won't it be the most likely target for vector? Meaning at that point, rv64gcbv/lp64d would be less useful or important. > > If we need to > > have (and test) more targets that are actually useful, so be it. But we > > don't want to be stuck testing targets nobody uses or that provide no > > testing value, and removing them is usually harder than adding them. > > Ya, that's kind of my worry here. We'd be going out on a limb here by > targeting something without hardware availability, we've already got some > baggage floating around from lightly-used targets and it'd be best to avoid > too much of that. > Maybe make an explicit note that if/when the vector ABI is in gcc, the target will be switched to that, rather than another target being added. Then there's some notice for people to not rely on rv64gcbv/lp64d, or at least put up support and/or evidence of a use case to retain the target. > IMO it's really more of a question for users/distros -- and I'm definitely a > crazy person on that front, I run Gentoo ;) >