From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS31976 209.132.180.0/23 X-Spam-Status: No, score=-4.0 required=3.0 tests=AWL,BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_EF,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED,SPF_HELO_PASS,SPF_PASS shortcircuit=no autolearn=ham autolearn_force=no version=3.4.2 Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dcvr.yhbt.net (Postfix) with ESMTPS id 6553120248 for ; Tue, 19 Mar 2019 16:07:30 +0000 (UTC) DomainKey-Signature: a=rsa-sha1; c=nofws; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:references:date:in-reply-to :message-id:mime-version:content-type; q=dns; s=default; b=UfT5K VRb7/pottYzAWrDbpJnU1hpfdA4LJ5sXE9Yp1iCpYFHVIGg4889LMuFJTzG82KtT oVoCG/DuOWjc6K53DMSgyDeOtkWbpQdeZ0qeeg5500ENEAksil4z9QoilM8Q8oIa K4ENd7HT1CqulEJSECvKdcd9Ysnhm4AhBxcrlE= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=sourceware.org; h=list-id :list-unsubscribe:list-subscribe:list-archive:list-post :list-help:sender:from:to:cc:subject:references:date:in-reply-to :message-id:mime-version:content-type; s=default; bh=8l6GQ+BEZFi x+aMEAbt+9eJUyds=; b=mTG44M4Y5R4nDZX3lbUV3Qd/GMrr6HfFZ1/m01YHS1c kocittCAfVGKeZnTEsB8MhqCK6fWZpOSDZMPGdxGIeQiM2biBXND1ZxHAPlO/mp5 Bb0vvG2nAhDmUUV8HzOrmhsMiiH5Gr5h1TAGDQYvQtXZ7s5gEvG+Tw6SaL2JUtUk = Received: (qmail 10743 invoked by alias); 19 Mar 2019 16:07:28 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Received: (qmail 10724 invoked by uid 89); 19 Mar 2019 16:07:27 -0000 Authentication-Results: sourceware.org; auth=none X-HELO: albireo.enyo.de From: Florian Weimer To: Szabolcs Nagy Cc: nd , Joseph Myers , "libc-alpha\@sourceware.org" Subject: Re: Add AArch64 HWCAPs from Linux 5.0 References: <87bm27x79r.fsf@mid.deneb.enyo.de> <02c15fb3-47e5-1900-c8d9-418c6e942748@arm.com> Date: Tue, 19 Mar 2019 17:07:21 +0100 In-Reply-To: <02c15fb3-47e5-1900-c8d9-418c6e942748@arm.com> (Szabolcs Nagy's message of "Tue, 19 Mar 2019 16:03:51 +0000") Message-ID: <87d0mmvoee.fsf@mid.deneb.enyo.de> MIME-Version: 1.0 Content-Type: text/plain * Szabolcs Nagy: > the ilp32 port passes uint64_t hwcap to the resolver currently > so the top 32bit can be used by glibc to signal the presence > of additional arguments to the resolver (this should work for > both lp64 and ilp32) however i havent worked out yet what > the additional argument should be (so it's extensible reasonably > in the future). It could be a pointer to a struct with the struct size as the first member. That's really simple and could work on other architectures, too. Or we could delay IFUNC resolvers after other relocations, so that IFUNC resolvers can use arbitrary data symbols from the dynamic loader because all data relocations have been processed before they run. Then we won't have to add additional IFUNC resolver arguments ever again, and can use the regular ABI maintenance to deal with compatibility issues.