From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <hubicka@kam.mff.cuni.cz>
Received: from nikam.ms.mff.cuni.cz (nikam.ms.mff.cuni.cz [195.113.20.16])
 by sourceware.org (Postfix) with ESMTPS id D1AD7398B865
 for <gcc-patches@gcc.gnu.org>; Thu,  8 Jul 2021 13:16:35 +0000 (GMT)
DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org D1AD7398B865
Authentication-Results: sourceware.org;
 dmarc=none (p=none dis=none) header.from=ucw.cz
Authentication-Results: sourceware.org; spf=none smtp.mailfrom=kam.mff.cuni.cz
Received: by nikam.ms.mff.cuni.cz (Postfix, from userid 16202)
 id 58D88282AD9; Thu,  8 Jul 2021 15:16:34 +0200 (CEST)
Date: Thu, 8 Jul 2021 15:16:34 +0200
From: Jan Hubicka <hubicka@ucw.cz>
To: Martin Jambor <mjambor@suse.cz>
Cc: GCC Patches <gcc-patches@gcc.gnu.org>
Subject: Re: [PATCH] ipa-sra: Fix thinko when overriding
 safe_to_import_accesses (PR 101066)
Message-ID: <20210708131634.GA52801@kam.mff.cuni.cz>
References: <ri6y2b3dlgr.fsf@suse.cz>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <ri6y2b3dlgr.fsf@suse.cz>
User-Agent: Mutt/1.10.1 (2018-07-13)
X-Spam-Status: No, score=-8.2 required=5.0 tests=BAYES_00,
 HEADER_FROM_DIFFERENT_DOMAINS, KAM_DMARC_STATUS, KAM_LAZY_DOMAIN_SECURITY,
 RCVD_IN_MSPIKE_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE,
 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 <gcc-patches.gcc.gnu.org>
List-Unsubscribe: <https://gcc.gnu.org/mailman/options/gcc-patches>,
 <mailto:gcc-patches-request@gcc.gnu.org?subject=unsubscribe>
List-Archive: <https://gcc.gnu.org/pipermail/gcc-patches/>
List-Post: <mailto:gcc-patches@gcc.gnu.org>
List-Help: <mailto:gcc-patches-request@gcc.gnu.org?subject=help>
List-Subscribe: <https://gcc.gnu.org/mailman/listinfo/gcc-patches>,
 <mailto:gcc-patches-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Thu, 08 Jul 2021 13:16:37 -0000

Hi,
> 2021-06-16  Martin Jambor  <mjambor@suse.cz>
> 
> 	PR ipa/101066
> 	* ipa-sra.c (class isra_call_summary): New member
> 	m_before_any_store, initialize it in the constructor.
> 	(isra_call_summary::dump): Dump the new field.
> 	(ipa_sra_call_summaries::duplicate): Copy it.
> 	(process_scan_results): Set it.
> 	(isra_write_edge_summary): Stream it.
> 	(isra_read_edge_summary): Likewise.
> 	(param_splitting_across_edge): Only override
> 	safe_to_import_accesses if m_before_any_store is set.
> 
> gcc/testsuite/ChangeLog:
> 
> 2021-06-16  Martin Jambor  <mjambor@suse.cz>
> 
> 	PR ipa/101066
> 	* gcc.dg/ipa/pr101066.c: New test.
OK, thanks!

The analysis disabling transformation on any memory store is overly
conservative.  We have pointer (which is a parameter and comes from
outer world) and no type infomration, however alias oracle will still be
able to disambiguate when memory access is to non-escaping local memory
or mallocated memory block etc.

Honza