From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca by simark.ca with LMTP id smSOHsXRT2OUXA4AWB0awg (envelope-from ) for ; Wed, 19 Oct 2022 06:30:29 -0400 Received: by simark.ca (Postfix, from userid 112) id 6529A1E112; Wed, 19 Oct 2022 06:30:29 -0400 (EDT) Authentication-Results: simark.ca; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=KG6FxIyd; dkim-atps=neutral X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on simark.ca X-Spam-Level: X-Spam-Status: No, score=-2.0 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RDNS_DYNAMIC,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 Received: from sourceware.org (ip-8-43-85-97.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPS id 0FB561E0D3 for ; Wed, 19 Oct 2022 06:30:29 -0400 (EDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 546263858D39 for ; Wed, 19 Oct 2022 10:30:27 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 546263858D39 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1666175427; bh=VIf1j+5LIcsKqg7ac0TzXvMybuDVwVHhIcSZAHAa4a8=; h=To:Subject:References:Date:In-Reply-To:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To:Cc: From; b=KG6FxIydzmvth/QZU+cN/BqA33mEmM3EWNU/sQn/ZAzl9W2m2Hdv5lC7wfKgUQZau 39N+uZlBzP8+waRW1Me28YT7ZtSQ05Rb6F52Ne6X5cUPTcZXbtP/+gwQ4uHE+MWDmt 1HgJqtvwQxDw+C/EOVgjvkX7jG2btQstFKZ+SC1Y= Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id 5BFD33858D39 for ; Wed, 19 Oct 2022 10:29:12 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 5BFD33858D39 Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-75-uM_YEaa6O_-vawDjDJEwsg-1; Wed, 19 Oct 2022 06:29:08 -0400 X-MC-Unique: uM_YEaa6O_-vawDjDJEwsg-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.rdu2.redhat.com [10.11.54.2]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 7784187B2A4; Wed, 19 Oct 2022 10:29:03 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.2.16.74]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 29DB1414A819; Wed, 19 Oct 2022 10:28:55 +0000 (UTC) To: Pedro Alves Subject: Re: gmp's c++ interface / mpz_class References: Date: Wed, 19 Oct 2022 12:28:53 +0200 In-Reply-To: (Pedro Alves's message of "Fri, 14 Oct 2022 21:42:10 +0100") Message-ID: <87lepcgl96.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.1 on 10.11.54.2 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-BeenThere: gdb@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , From: Florian Weimer via Gdb Reply-To: Florian Weimer Cc: gdb@sourceware.org, "Zaric, Zoran \(Zare\)" Errors-To: gdb-bounces+public-inbox=simark.ca@sourceware.org Sender: "Gdb" * Pedro Alves: > Hmm. Since we don't need infinite precision, it will end up a lot > more efficient to roll our own type, with fixed (or templated) storage > size. Like a simplified version of GCC's wide_int. Not sure yet > whether efficiency really matters in practice, but I suspect it does. > > I'd still be curious about GMP's native C++ interface. I tried to use it recently in a hobby project, but it turned out to be a poor fit because it's not integrated well with C++11 and later features (no move constructors, no rvalue references). The unconditional use of malloc is rather off-putting, too. I'm contemplating to use tagged integers/pointers as the main representation, with heap allocation only on demand, maybe using the the mpn* functions directly, or perhaps copy things out of a long-lasting mpz_t object that's used as a temporary for arithmetic. For 72-bit integers, that seems a bit over the top, though. Thanks, Florian