From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) by sourceware.org (Postfix) with ESMTP id 1BF63385840D for ; Fri, 17 Sep 2021 22:16:06 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 1BF63385840D Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=kernel.crashing.org Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=kernel.crashing.org Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id 18HMF5YS030591; Fri, 17 Sep 2021 17:15:05 -0500 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id 18HMF5kg030590; Fri, 17 Sep 2021 17:15:05 -0500 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Fri, 17 Sep 2021 17:15:05 -0500 From: Segher Boessenkool To: Bill Schmidt Cc: "Kewen.Lin" , GCC Patches , David Edelsohn Subject: Re: [PATCH] rs6000: Parameterize some const values for density test Message-ID: <20210917221505.GX1583@gate.crashing.org> References: <3e1e4dda-7fd2-6f40-6270-b55ce2d1ed0d@linux.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <3e1e4dda-7fd2-6f40-6270-b55ce2d1ed0d@linux.ibm.com> User-Agent: Mutt/1.4.2.3i X-Spam-Status: No, score=-3.4 required=5.0 tests=BAYES_00, JMQ_SPF_NEUTRAL, KAM_DMARC_STATUS, SPF_HELO_PASS, SPF_PASS, TXREP autolearn=no 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, 17 Sep 2021 22:16:08 -0000 Hi! On Fri, Sep 17, 2021 at 11:27:09AM -0500, Bill Schmidt wrote: > On 9/15/21 3:52 AM, Kewen.Lin wrote: > >+-param=rs6000-density-pct-threshold= > >+Target Undocumented Joined UInteger Var(rs6000_density_pct_threshold) > >Init(85) IntegerRange(0, 99) Param > >+When costing for loop vectorization, we probably need to penalize the > >loop body cost if the existing cost model may not adequately reflect > >delays from unavailable vector resources. We collect the cost for > >vectorized statements and non-vectorized statements separately, check the > >proportion of vec_cost to total cost of vec_cost and non vec_cost, and > >penalize only if the proportion exceeds the threshold specified by this > >parameter. The default value is 85. > >+ > >+-param=rs6000-density-size-threshold= > >+Target Undocumented Joined UInteger Var(rs6000_density_size_threshold) > >Init(70) IntegerRange(0, 99) Param > > I think 99 is not a sufficient upper bound.  This is a counting value > that could in theory get much higher.  Can you set it to something > ridiculous like IntegerRange(0, 1000)? It is a percentage. (0,100) is the maximum that makes any sense :-) It may be useful to make it a bit more sensitive than hundreds, but it is a heuristic anyway, this will work fine. But allowing 100 will be good. Segher