From patchwork Fri May 7 09:38:22 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pierre-Marie de Rodat X-Patchwork-Id: 1475417 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org (client-ip=2620:52:3:1:0:246e:9693:128c; helo=sourceware.org; envelope-from=gcc-patches-bounces@gcc.gnu.org; receiver=) Received: from sourceware.org (server2.sourceware.org [IPv6:2620:52:3:1:0:246e:9693:128c]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 4Fc53w45f4z9sj5 for ; Fri, 7 May 2021 19:38:36 +1000 (AEST) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id A6DCC3938C22; Fri, 7 May 2021 09:38:27 +0000 (GMT) X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from rock.gnat.com (rock.gnat.com [IPv6:2620:20:4000:0:a9e:1ff:fe9b:1d1]) by sourceware.org (Postfix) with ESMTP id 3CCC638930D3 for ; Fri, 7 May 2021 09:38:23 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org 3CCC638930D3 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=adacore.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=derodat@adacore.com Received: from localhost (localhost.localdomain [127.0.0.1]) by filtered-rock.gnat.com (Postfix) with ESMTP id 10B2756359; Fri, 7 May 2021 05:38:23 -0400 (EDT) X-Virus-Scanned: Debian amavisd-new at gnat.com Received: from rock.gnat.com ([127.0.0.1]) by localhost (rock.gnat.com [127.0.0.1]) (amavisd-new, port 10024) with LMTP id mkqhqx4g1T1T; Fri, 7 May 2021 05:38:23 -0400 (EDT) Received: from tron.gnat.com (tron.gnat.com [205.232.38.10]) by rock.gnat.com (Postfix) with ESMTP id F2C0156358; Fri, 7 May 2021 05:38:22 -0400 (EDT) Received: by tron.gnat.com (Postfix, from userid 4862) id F2072FA; Fri, 7 May 2021 05:38:22 -0400 (EDT) Date: Fri, 7 May 2021 05:38:22 -0400 From: Pierre-Marie de Rodat To: gcc-patches@gcc.gnu.org Subject: [Ada] Raise Constraint_Error for Compose and Scaling if Machine_Overflows Message-ID: <20210507093822.GA140595@adacore.com> MIME-Version: 1.0 Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) X-Spam-Status: No, score=-12.5 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: gcc-patches@gcc.gnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gcc-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Eric Botcazou Errors-To: gcc-patches-bounces@gcc.gnu.org Sender: "Gcc-patches" This is an optional behavior specified by the RM and it makes sense to do it when T'Machine_Overflows is True for the sake of consistency. Tested on x86_64-pc-linux-gnu, committed on trunk gcc/ada/ * libgnat/s-fatgen.adb (Scaling): Raise Constraint_Error in the overflow case when T'Machine_Overflows is True. diff --git a/gcc/ada/libgnat/s-fatgen.adb b/gcc/ada/libgnat/s-fatgen.adb --- a/gcc/ada/libgnat/s-fatgen.adb +++ b/gcc/ada/libgnat/s-fatgen.adb @@ -771,12 +771,19 @@ package body System.Fat_Gen is -- Check for overflow if Adjustment > IEEE_Emax - Exp then - XX := 0.0; - return (if Minus then -1.0 / XX else 1.0 / XX); - pragma Annotate - (CodePeer, Intentional, "overflow check", "Infinity produced"); - pragma Annotate - (CodePeer, Intentional, "divide by zero", "Infinity produced"); + -- Optionally raise Constraint_Error as per RM A.5.3(29) + + if T'Machine_Overflows then + raise Constraint_Error with "Too large exponent"; + + else + XX := 0.0; + return (if Minus then -1.0 / XX else 1.0 / XX); + pragma Annotate (CodePeer, Intentional, "overflow check", + "Infinity produced"); + pragma Annotate (CodePeer, Intentional, "divide by zero", + "Infinity produced"); + end if; -- Check for underflow