From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-ed1-x531.google.com (mail-ed1-x531.google.com [IPv6:2a00:1450:4864:20::531]) by sourceware.org (Postfix) with ESMTPS id 748893858D35 for ; Fri, 5 Nov 2021 09:48:41 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 748893858D35 Received: by mail-ed1-x531.google.com with SMTP id g10so30902873edj.1 for ; Fri, 05 Nov 2021 02:48:41 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=n7VtB0x8BM2QV0VfVKtOHQWwIZuvWRexww1KnejjJX8=; b=2PDcSHxj3s2dU4Bi3WVMUakhg5pUI1HAkpTdQkVHatYHVkfcOy30AePEO9Ga4ngGCK GswW1vo++3rN2OQy17l8jXqyNbL/yfnQOKU5/uKxwrvWsaJiPoCZMqrLF4Ke30UaKbGy VVVLe8I6/jWapROaNk+WwER492hrrtnWG4ViJPJVh+yqicjSaH+sfQQmk6797XS3fj0o PiqPbOPBwNn/T93GoDRwBUaNfwA3WEpsJovJjWi6dQj7785elLm5bIIkCM/GrNrkDyDJ N9/vapWFlq3H646NWGoJzyOZrTtja04T54+2mCGnq/lSuDEg+MtSkLI3CRaXGgXDWjFT r6Jw== X-Gm-Message-State: AOAM5331q60g88d8SZDUwM6qsb2IuOuq43rt+TUwC+sMOz0iRgDT+okj ENbC5JbCNIAQeB/cfsZ7FCJXd3qDhG4J9A5uZng= X-Google-Smtp-Source: ABdhPJyfRpIW5Fhy1jq56dbKwe5UQYjCtVtvsK01U4aqpH0LkwiCLmCxa2KVn/YUFgEYP9vkFbLqualdB9W0nxI1e3s= X-Received: by 2002:a17:906:b201:: with SMTP id p1mr71304811ejz.571.1636105720512; Fri, 05 Nov 2021 02:48:40 -0700 (PDT) MIME-Version: 1.0 References: <20211105022024.27921-1-hongtao.liu@intel.com> In-Reply-To: <20211105022024.27921-1-hongtao.liu@intel.com> From: Richard Biener Date: Fri, 5 Nov 2021 10:48:29 +0100 Message-ID: Subject: Re: [PATCH] Add !flag_signaling_nans to simplifcation: (trunc)copysign((extend)a, (extend)b) to copysign (a, b). To: liuhongt Cc: GCC Patches , "Joseph S. Myers" Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-8.5 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, FREEMAIL_FROM, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) 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: , X-List-Received-Date: Fri, 05 Nov 2021 09:48:43 -0000 On Fri, Nov 5, 2021 at 3:20 AM liuhongt wrote: > > > Note that this is not safe with -fsignaling-nans, so needs to be disabled > > for that option (if there isn't already logic somewhere with that effect), > > because the extend will convert a signaling NaN to quiet (raising > > "invalid"), but copysign won't, so this transformation could result in a > > signaling NaN being wrongly returned when the original code would never > > have returned a signaling NaN. > > > > -- > > Joseph S. Myers > > joseph@codesourcery.com > > Bootstrapped and regtested on x86_64-linux-gnu{-m32,}. > Ok for trunk? > > gcc/ChangeLog > > * match.pd > (Simplifcation (trunc)copysign((extend)a, (extend)b) to > .COPYSIGN (a, b)): Add !flag_signaling_nans. > --- > gcc/match.pd | 1 + > 1 file changed, 1 insertion(+) > > diff --git a/gcc/match.pd b/gcc/match.pd > index fb1065dc0e6..d6a8dd0dd20 100644 > --- a/gcc/match.pd > +++ b/gcc/match.pd > @@ -6176,6 +6176,7 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT) > (simplify > (convert (copysigns (convert@2 @0) (convert @1))) > (if (optimize > + && !flag_signaling_nans Please use !HONOR_SNANS (@2) OK with that change. > && types_match (type, TREE_TYPE (@0)) > && types_match (type, TREE_TYPE (@1)) > && TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (@2)) > -- > 2.18.1 >