From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 28407 invoked by alias); 20 Jun 2017 11:34:21 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 28392 invoked by uid 89); 20 Jun 2017 11:34:20 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.3 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=ham version=3.3.2 spammy= X-HELO: mail-oi0-f50.google.com Received: from mail-oi0-f50.google.com (HELO mail-oi0-f50.google.com) (209.85.218.50) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Tue, 20 Jun 2017 11:34:19 +0000 Received: by mail-oi0-f50.google.com with SMTP id b6so70458574oia.1 for ; Tue, 20 Jun 2017 04:34:19 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:cc; bh=nI3MDG9ES5AJa9NSgOBAyv/sTioiHyku1YeKDPqEXJU=; b=sQuqv+HNF+/ZkxRIXA3lOld8ca3j5zpGE9aUl07Bumy/uLN7od70UyJk6PF74PSeoz 6PJxcCLURFF8Df4GKKc9DowxsQMQLekFVnC0ciL4+IY+CZCOaSs4q1WWYcgAEzJbEEa8 IBPj9MNN2sdzoj9qsQRKBBhcIsUBII/i9FQP0bKyZmhuV2XVhT3XgNGq5EuI1Agda/is FaHp7Qfhgil1/7paQ1U+Yd7ANve8IjadlqaBXaFWe3KKfvRJuG7KKlYZ6fGKx9WIP+2r 7boNK4ZYe3v6HasuICQKAiXIZ1eH1RdHZSBDq6iO0ynRbppmR1oipf/7c/CO3/bgKrWS dIfQ== X-Gm-Message-State: AKS2vOzzRL3wm1EndyZEjo8juVA7DccChuvuJvsH1O8YLhpKIAa0pg3v PDpXnygDo2Nmqfi2THvL8h22Z561kw== X-Received: by 10.202.180.67 with SMTP id d64mr13145071oif.212.1497958457922; Tue, 20 Jun 2017 04:34:17 -0700 (PDT) MIME-Version: 1.0 Received: by 10.157.37.66 with HTTP; Tue, 20 Jun 2017 04:34:17 -0700 (PDT) In-Reply-To: References: From: Richard Biener Date: Tue, 20 Jun 2017 11:34:00 -0000 Message-ID: Subject: Re: [PATCH GCC][11/13]Annotate partition by its parallelism execution type To: "Bin.Cheng" Cc: "gcc-patches@gcc.gnu.org" Content-Type: text/plain; charset="UTF-8" X-IsSubscribed: yes X-SW-Source: 2017-06/txt/msg01437.txt.bz2 On Tue, Jun 20, 2017 at 11:18 AM, Bin.Cheng wrote: > On Fri, Jun 16, 2017 at 11:10 AM, Richard Biener > wrote: >> On Mon, Jun 12, 2017 at 7:03 PM, Bin Cheng wrote: >>> Hi, >>> This patch checks and records if partition can be executed in parallel by >>> looking if there exists data dependence cycles. The information is needed >>> for distribution because the idea is to distribute parallel type partitions >>> away from sequential ones. I believe current distribution doesn't work >>> very well because it does blind distribution/fusion. >>> Bootstrap and test on x86_64 and AArch64. Is it OK? >> >> + /* In case of no data dependence. */ >> + if (DDR_ARE_DEPENDENT (ddr) == chrec_known) >> + return false; >> + /* Or the data dependence can be resolved by compilation time alias >> + check. */ >> + else if (!alias_sets_conflict_p (get_alias_set (DR_REF (dr1)), >> + get_alias_set (DR_REF (dr2)))) >> + return false; >> >> dependence analysis should use TBAA already, in which cases do you need this? >> It seems to fall foul of the easy mistake of not honoring GCCs memory model >> as well ... see dr_may_alias_p. > I see. Patch updated with this branch removed. > >> >> + /* Further check if any data dependence prevents us from executing the >> + partition parallelly. */ >> + EXECUTE_IF_SET_IN_BITMAP (partition->reads, 0, i, bi) >> + { >> + dr1 = (*datarefs_vec)[i]; >> + EXECUTE_IF_SET_IN_BITMAP (partition->writes, 0, j, bj) >> + { >> >> what about write-write dependences? >> >> + EXECUTE_IF_SET_IN_BITMAP (partition->reads, 0, i, bi) >> + { >> + dr1 = (*datarefs_vec)[i]; >> + EXECUTE_IF_SET_IN_BITMAP (partition->writes, i + 1, j, bj) >> + { >> + dr2 = (*datarefs_vec)[j]; >> + /* Partition can only be executed sequentially if there is any >> + data dependence cycle. */ >> >> exact copy of the loop nest follows?! Maybe you meant to iterate >> over writes in the first loop. > Yes, this is a copy-paste typo. Patch is also simplified because > read/write are recorded together now. Is it OK? Ok. Thanks, Richard. > Thanks, > bin > 2017-06-07 Bin Cheng > > * tree-loop-distribution.c (enum partition_type): New. > (struct partition): New field type. > (partition_merge_into): Update partition type. > (data_dep_in_cycle_p): New function. > (build_rdg_partition_for_vertex): Compute partition type. > (rdg_build_partitions): Dump partition type.