From patchwork Wed Mar 9 11:19:23 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xi Ruoyao X-Patchwork-Id: 51815 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id E05033858423 for ; Wed, 9 Mar 2022 11:19:57 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E05033858423 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gcc.gnu.org; s=default; t=1646824797; bh=uuqmYCERf+7XbTwrmWjgliZHTaM8C+dAwnjjbVC3Lvg=; h=Subject:To:Date:List-Id:List-Unsubscribe:List-Archive:List-Post: List-Help:List-Subscribe:From:Reply-To:Cc:From; b=bfhBu+JtjMN7rKX0qJTNv3LlLjISPI6CHSX8N1HQ3uUm+ePweVGXPp1uibkmOuJPO 24QgF+nRNG0eBuDDq/N/A585XWsHn4zJslJFw8oCCNwUV1UJKcp8NxncyyZG+O3yGO wV+4PEgfUQj9CHI1Bq1JeGfI28eb9EqjNYnJzSmE= X-Original-To: gcc-patches@gcc.gnu.org Delivered-To: gcc-patches@gcc.gnu.org Received: from mengyan1223.wang (mengyan1223.wang [89.208.246.23]) by sourceware.org (Postfix) with ESMTPS id 528053858D28 for ; Wed, 9 Mar 2022 11:19:28 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 528053858D28 Received: from localhost.localdomain (localhost [127.0.0.1]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (P-256) server-signature ECDSA (P-384) server-digest SHA384) (Client did not present a certificate) (Authenticated sender: xry111@mengyan1223.wang) by mengyan1223.wang (Postfix) with ESMTPSA id E9C2166246; Wed, 9 Mar 2022 06:19:25 -0500 (EST) Message-ID: Subject: [PATCH] cse: avoid signed overflow in compute_const_anchors [PR 104843] To: gcc-patches@gcc.gnu.org Date: Wed, 09 Mar 2022 19:19:23 +0800 User-Agent: Evolution 3.42.4 MIME-Version: 1.0 X-Spam-Status: No, score=-3037.8 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, JMQ_SPF_NEUTRAL, SPF_HELO_PASS, SPF_PASS, TXREP, T_SCC_BODY_TEXT_LINE 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-Patchwork-Original-From: Xi Ruoyao via Gcc-patches From: Xi Ruoyao Reply-To: Xi Ruoyao Cc: Richard Sandiford , Jeff Law Errors-To: gcc-patches-bounces+patchwork=sourceware.org@gcc.gnu.org Sender: "Gcc-patches" Bootstrapped and tested on mips64el-linux-gnuabi64, and MIPS is the only port with a non-zero targetm.const_anchor. Ok for trunk? -- >8 -- With a non-zero const_anchor, the behavior of this function relied on signed overflow. gcc/ PR rtl-optimization/104843 * cse.cc (compute_const_anchors): Cast to unsigned HOST_WIDE_INT to perform overflow arithmetics safely. --- gcc/cse.cc | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/gcc/cse.cc b/gcc/cse.cc index a18b599d324..7c39a009449 100644 --- a/gcc/cse.cc +++ b/gcc/cse.cc @@ -1169,10 +1169,10 @@ compute_const_anchors (rtx cst, HOST_WIDE_INT *lower_base, HOST_WIDE_INT *lower_offs, HOST_WIDE_INT *upper_base, HOST_WIDE_INT *upper_offs) { - HOST_WIDE_INT n = INTVAL (cst); + unsigned HOST_WIDE_INT n = INTVAL (cst); *lower_base = n & ~(targetm.const_anchor - 1); - if (*lower_base == n) + if (*lower_base == INTVAL (cst)) return false; *upper_base =