From patchwork Tue Dec 27 04:17:10 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexandre Oliva X-Patchwork-Id: 1719569 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=gcc.gnu.org (client-ip=8.43.85.97; helo=sourceware.org; envelope-from=gcc-patches-bounces+incoming=patchwork.ozlabs.org@gcc.gnu.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=gcc.gnu.org header.i=@gcc.gnu.org header.a=rsa-sha256 header.s=default header.b=ofbcxAUF; dkim-atps=neutral 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 ECDSA (P-384) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4Nh1b90MlHz23dc for ; Tue, 27 Dec 2022 15:17:39 +1100 (AEDT) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 55A593858C27 for ; Tue, 27 Dec 2022 04:17:37 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 55A593858C27 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1672114657; bh=OfNllI4GrBohry2jwd8P10zjUvrD9Wb28lEW84qMX28=; h=To:Subject:References:Date:In-Reply-To:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=ofbcxAUFhKMtw/gPIPtr4UGmHiKoRxZDImzALU9rc77U+4uI8/wdilu/2zbsJgVUG t+CQK/1Ns1J/6L9D51JkDASjhhleQZlh5Rxn2P5Ww8yXOtFdTL0lU61mWg7+IwrOxo KmQGPmxA8bKRC9h7JdFhlmtzxHsVbDMI6SuTB8wU= 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 ESMTPS id C83F53858D38 for ; Tue, 27 Dec 2022 04:17:17 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org C83F53858D38 Received: from localhost (localhost.localdomain [127.0.0.1]) by filtered-rock.gnat.com (Postfix) with ESMTP id 90F4F1162A6; Mon, 26 Dec 2022 23:17:17 -0500 (EST) 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 pzSwmPrT6DlK; Mon, 26 Dec 2022 23:17:17 -0500 (EST) Received: from free.home (tron.gnat.com [IPv6:2620:20:4000:0:46a8:42ff:fe0e:e294]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by rock.gnat.com (Postfix) with ESMTPS id 3139D11628F; Mon, 26 Dec 2022 23:17:17 -0500 (EST) Received: from livre (livre.home [172.31.160.2]) by free.home (8.15.2/8.15.2) with ESMTPS id 2BR4HARn711938 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Tue, 27 Dec 2022 01:17:10 -0300 To: gcc-patches@gcc.gnu.org Subject: [01/13] scoped tables: insert before further lookups Organization: Free thinker, does not speak for AdaCore References: Date: Tue, 27 Dec 2022 01:17:10 -0300 In-Reply-To: (Alexandre Oliva's message of "Tue, 27 Dec 2022 01:07:35 -0300") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.3 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.84 X-Spam-Status: No, score=-12.2 required=5.0 tests=BAYES_00, GIT_PATCH_0, KAM_DMARC_STATUS, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) 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-Patchwork-Original-From: Alexandre Oliva via Gcc-patches From: Alexandre Oliva Reply-To: Alexandre Oliva Errors-To: gcc-patches-bounces+incoming=patchwork.ozlabs.org@gcc.gnu.org Sender: "Gcc-patches" Avoid hash table lookups between requesting an insert and storing the inserted value in avail_exprs_stack. Lookups before the insert is completed could fail to find double-hashed elements. Regstrapped on x86_64-linux-gnu. Ok to install? for gcc/ChangeLog * tree-ssa-scopedtables.cc (avail_exprs_stack::lookup_avail_expr): Finish hash table insertion before further lookups. --- gcc/tree-ssa-scopedtables.cc | 10 +++++----- 1 file changed, 5 insertions(+), 5 deletions(-) diff --git a/gcc/tree-ssa-scopedtables.cc b/gcc/tree-ssa-scopedtables.cc index 6d203ef89ecef..3e6e129e7d5d3 100644 --- a/gcc/tree-ssa-scopedtables.cc +++ b/gcc/tree-ssa-scopedtables.cc @@ -259,11 +259,6 @@ avail_exprs_stack::lookup_avail_expr (gimple *stmt, bool insert, bool tbaa_p, } else if (*slot == NULL) { - /* If we did not find the expression in the hash table, we may still - be able to produce a result for some expressions. */ - tree retval = avail_exprs_stack::simplify_binary_operation (stmt, - element); - /* We have, in effect, allocated *SLOT for ELEMENT at this point. We must initialize *SLOT to a real entry, even if we found a way to prove ELEMENT was a constant after not finding ELEMENT @@ -277,6 +272,11 @@ avail_exprs_stack::lookup_avail_expr (gimple *stmt, bool insert, bool tbaa_p, class expr_hash_elt *element2 = new expr_hash_elt (element); *slot = element2; + /* If we did not find the expression in the hash table, we may still + be able to produce a result for some expressions. */ + tree retval = avail_exprs_stack::simplify_binary_operation (stmt, + element); + record_expr (element2, NULL, '2'); return retval; }