From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 93749 invoked by alias); 27 Feb 2017 08:15:34 -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 93566 invoked by uid 89); 27 Feb 2017 08:15:11 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-11.9 required=5.0 tests=BAYES_00,GIT_PATCH_2,GIT_PATCH_3,RP_MATCHES_RCVD,SPF_PASS autolearn=ham version=3.3.2 spammy= 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 ESMTP; Mon, 27 Feb 2017 08:15:08 +0000 Received: from relay1.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx2.suse.de (Postfix) with ESMTP id 7C3B8ABCD; Mon, 27 Feb 2017 08:15:05 +0000 (UTC) Date: Mon, 27 Feb 2017 08:19:00 -0000 From: Richard Biener To: Jakub Jelinek cc: gcc-patches@gcc.gnu.org Subject: Re: [PATCH] FMA_EXPR can cause -fnon-call-exceptions with floating point args (PR middle-end/79396) In-Reply-To: <20170225082332.GS1849@tucnak> Message-ID: References: <20170224205625.GP1849@tucnak> <01F56564-E68F-47AC-B3F8-DBDB0069D319@suse.de> <20170225082332.GS1849@tucnak> User-Agent: Alpine 2.20 (LSU 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-SW-Source: 2017-02/txt/msg01588.txt.bz2 On Sat, 25 Feb 2017, Jakub Jelinek wrote: > On Sat, Feb 25, 2017 at 08:42:33AM +0100, Richard Biener wrote: > > On February 24, 2017 9:56:25 PM GMT+01:00, Jakub Jelinek wrote: > > >Hi! > > > > > >On the following testcase we replace a PLUS_EXPR (which is considered > > >throwing with -fnon-call-exceptions when it has floating point > > >arguments > > >and FP exceptions or sNaNs are enabled) with a FMA_EXPR; I believe it > > >can throw the same, but stmt_could_throw_1_p doesn't think so (as it is > > >not unary/binary/comparison). While we could tweak the widen_mul patch > > >to deal with dropping EH from gsi_replace and cleaning up cfg etc., I > > >believe the right fix is to fix stmt_could_throw_1_p. > > > > > >Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk? > > > > OK. Can you make sure this is then consistent with the other throw predicates?. > > may_trap_p_1 handles FMA right, no idea what other predicates could cover > that on RTL. But you're right, operation_could_trap_p used by > tree_could_trap_p needs the same treatment: Yes, that was what I remembered (used for example by vn_nary_may_trap). Ok. Thanks, Richard. > 2017-02-25 Jakub Jelinek > > PR middle-end/79396 > * tree-eh.c (operation_could_trap_p, stmt_could_throw_1_p): Handle > FMA_EXPR like tcc_binary or tcc_unary. > > * g++.dg/opt/pr79396.C: New test. > > --- gcc/tree-eh.c.jj 2017-02-24 21:39:01.240088691 +0100 > +++ gcc/tree-eh.c 2017-02-25 09:21:06.017859379 +0100 > @@ -2513,7 +2513,8 @@ operation_could_trap_p (enum tree_code o > > if (TREE_CODE_CLASS (op) != tcc_comparison > && TREE_CODE_CLASS (op) != tcc_unary > - && TREE_CODE_CLASS (op) != tcc_binary) > + && TREE_CODE_CLASS (op) != tcc_binary > + && op != FMA_EXPR) > return false; > > return operation_could_trap_helper_p (op, fp_operation, honor_trapv, > @@ -2738,7 +2739,8 @@ stmt_could_throw_1_p (gimple *stmt) > > if (TREE_CODE_CLASS (code) == tcc_comparison > || TREE_CODE_CLASS (code) == tcc_unary > - || TREE_CODE_CLASS (code) == tcc_binary) > + || TREE_CODE_CLASS (code) == tcc_binary > + || code == FMA_EXPR) > { > if (is_gimple_assign (stmt) > && TREE_CODE_CLASS (code) == tcc_comparison) > --- gcc/testsuite/g++.dg/opt/pr79396.C.jj 2017-02-25 09:20:03.608706718 +0100 > +++ gcc/testsuite/g++.dg/opt/pr79396.C 2017-02-25 09:20:03.607706732 +0100 > @@ -0,0 +1,13 @@ > +// PR middle-end/79396 > +// { dg-do compile } > +// { dg-options "-fnon-call-exceptions -O2" } > +// { dg-additional-options "-mfma" { target i?86-*-* x86_64-*-* } } > + > +struct A { A (); ~A (); }; > + > +float > +foo (float x) > +{ > + A a; > + return __builtin_pow (x, 2) + 2; > +} > > > Jakub > > -- Richard Biener SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nuernberg)