From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 81148 invoked by alias); 27 Apr 2016 12:41:24 -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 81138 invoked by uid 89); 27 Apr 2016 12:41:23 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.9 required=5.0 tests=BAYES_00,RCVD_IN_DNSWL_NONE,RP_MATCHES_RCVD,SPF_PASS autolearn=ham version=3.3.2 spammy=2016-04-27, 20160427 X-HELO: mx2.suse.de Received: from mx2.suse.de (HELO mx2.suse.de) (195.135.220.15) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (CAMELLIA256-SHA encrypted) ESMTPS; Wed, 27 Apr 2016 12:41:13 +0000 Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id C731FABB0; Wed, 27 Apr 2016 12:41:07 +0000 (UTC) Date: Wed, 27 Apr 2016 12:41:00 -0000 From: Richard Biener To: Jakub Jelinek cc: gcc-patches@gcc.gnu.org Subject: Re: [PATCH] operand_equal_p checking (PR sanitizer/70683) In-Reply-To: <20160426225139.GZ26501@tucnak.zalov.cz> Message-ID: References: <20160426130238.GU26501@tucnak.zalov.cz> <20160426225139.GZ26501@tucnak.zalov.cz> User-Agent: Alpine 2.11 (LSU 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-SW-Source: 2016-04/txt/msg01624.txt.bz2 On Wed, 27 Apr 2016, Jakub Jelinek wrote: > On Tue, Apr 26, 2016 at 03:02:38PM +0200, Jakub Jelinek wrote: > > The debugging hack is too ugly and slows down the compiler (by artificially > > increasing number of collisions), so it is not appropriate, but perhaps we > > can add some internal only use OEP_* flag, pass it to the recursive calls > > of operand_equal_p and if not set and flag_checking, verify > > iterative_hash_expr equality in the outermost call). > > Here is the corresponding checking patch. It uncovered two further issues > in the tree.[ch] patch which I'm going to post momentarily. > Both patches together bootstrapped/regtested on x86_64-linux and i686-linux, > ok for trunk? Ok. Thanks, Richard. > 2016-04-27 Jakub Jelinek > > PR sanitizer/70683 > * tree-core.h (enum operand_equal_flag): Add OEP_NO_HASH_CHECK. > * fold-const.c (operand_equal_p): If flag_checking and > OEP_NO_HASH_CHECK is not set in flag, recurse with OEP_NO_HASH_CHECK > and if it returns non-zero, assert iterative_hash_expr on both > args is the same. > > --- gcc/tree-core.h.jj 2016-04-22 18:21:55.000000000 +0200 > +++ gcc/tree-core.h 2016-04-26 17:47:19.875753297 +0200 > @@ -765,7 +765,9 @@ enum operand_equal_flag { > OEP_ONLY_CONST = 1, > OEP_PURE_SAME = 2, > OEP_MATCH_SIDE_EFFECTS = 4, > - OEP_ADDRESS_OF = 8 > + OEP_ADDRESS_OF = 8, > + /* Internal within operand_equal_p: */ > + OEP_NO_HASH_CHECK = 16 > }; > > /* Enum and arrays used for tree allocation stats. > --- gcc/fold-const.c.jj 2016-04-22 18:21:32.000000000 +0200 > +++ gcc/fold-const.c 2016-04-26 18:30:40.919080701 +0200 > @@ -2749,6 +2749,25 @@ combine_comparisons (location_t loc, > int > operand_equal_p (const_tree arg0, const_tree arg1, unsigned int flags) > { > + /* When checking, verify at the outermost operand_equal_p call that > + if operand_equal_p returns non-zero then ARG0 and ARG1 has the same > + hash value. */ > + if (flag_checking && !(flags & OEP_NO_HASH_CHECK)) > + { > + if (operand_equal_p (arg0, arg1, flags | OEP_NO_HASH_CHECK)) > + { > + inchash::hash hstate0 (0), hstate1 (0); > + inchash::add_expr (arg0, hstate0, flags); > + inchash::add_expr (arg1, hstate1, flags); > + hashval_t h0 = hstate0.end (); > + hashval_t h1 = hstate1.end (); > + gcc_assert (h0 == h1); > + return 1; > + } > + else > + return 0; > + } > + > /* If either is ERROR_MARK, they aren't equal. */ > if (TREE_CODE (arg0) == ERROR_MARK || TREE_CODE (arg1) == ERROR_MARK > || TREE_TYPE (arg0) == error_mark_node > > > Jakub > > -- Richard Biener SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nuernberg)