From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 61538 invoked by alias); 21 Apr 2017 12:46:06 -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 61512 invoked by uid 89); 21 Apr 2017 12:46:05 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-11.1 required=5.0 tests=BAYES_00,GIT_PATCH_2,GIT_PATCH_3,KAM_ASCII_DIVIDERS,RP_MATCHES_RCVD,SPF_PASS autolearn=ham version=3.3.2 spammy=jane, Pure X-HELO: mx1.suse.de Received: from mx2.suse.de (HELO mx1.suse.de) (195.135.220.15) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 21 Apr 2017 12:46:04 +0000 Received: from relay2.suse.de (charybdis-ext.suse.de [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id BCE74AAF2 for ; Fri, 21 Apr 2017 12:46:03 +0000 (UTC) Date: Fri, 21 Apr 2017 13:08:00 -0000 From: Richard Biener To: gcc-patches@gcc.gnu.org Subject: Re: [PATCH] Fix PR79547 In-Reply-To: Message-ID: References: User-Agent: Alpine 2.20 (LSU 67 2015-01-07) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII X-SW-Source: 2017-04/txt/msg00947.txt.bz2 On Fri, 17 Feb 2017, Richard Biener wrote: > On Thu, 16 Feb 2017, Richard Biener wrote: > > > > > I am testing the following patch for PR79547. Those builtins do not > > return anything that can be used to re-construct the pointer(s) passed > > to them. > > > > Queued for GCC 8. > > Actually we need calluse constraints. Thus adjusted as follows. Re-bootstrapped & tested on x86_64-unknown-linux-gnu, applied to trunk. Richard. > Richard. > > 2017-02-17 Richard Biener > > PR tree-optimization/79547 > * tree-ssa-structalias.c (find_func_aliases_for_builtin_call): > Handle strlen, strcmp, strncmp, strcasecmp, strncasecmp, memcmp, > bcmp, strspn, strcspn, __builtin_object_size and __builtin_constant_p > without any constraints. > > * gcc.dg/tree-ssa/strlen-2.c: New testcase. > > Index: gcc/testsuite/gcc.dg/tree-ssa/strlen-2.c > =================================================================== > --- gcc/testsuite/gcc.dg/tree-ssa/strlen-2.c (nonexistent) > +++ gcc/testsuite/gcc.dg/tree-ssa/strlen-2.c (working copy) > @@ -0,0 +1,15 @@ > +/* { dg-do compile } */ > +/* { dg-options "-O2 -fdump-tree-strlen" } */ > + > +void f (unsigned); > + > +void f3 (void) > +{ > + char s[] = "1234"; > + > + f (__builtin_strlen (s)); > + f (__builtin_strlen (s)); > + f (__builtin_strlen (s)); > +} > + > +/* { dg-final { scan-tree-dump-times "strlen" 1 "strlen" } } */ > Index: gcc/tree-ssa-structalias.c > =================================================================== > --- gcc/tree-ssa-structalias.c (revision 245501) > +++ gcc/tree-ssa-structalias.c (working copy) > @@ -4474,6 +4474,40 @@ find_func_aliases_for_builtin_call (stru > process_all_all_constraints (lhsc, rhsc); > } > return true; > + /* Pure functions that return something not based on any object and > + that use the memory pointed to by their arguments (but not > + transitively). */ > + case BUILT_IN_STRCMP: > + case BUILT_IN_STRNCMP: > + case BUILT_IN_STRCASECMP: > + case BUILT_IN_STRNCASECMP: > + case BUILT_IN_MEMCMP: > + case BUILT_IN_BCMP: > + case BUILT_IN_STRSPN: > + case BUILT_IN_STRCSPN: > + { > + varinfo_t uses = get_call_use_vi (t); > + make_any_offset_constraints (uses); > + make_constraint_to (uses->id, gimple_call_arg (t, 0)); > + make_constraint_to (uses->id, gimple_call_arg (t, 1)); > + /* No constraints are necessary for the return value. */ > + return true; > + } > + case BUILT_IN_STRLEN: > + { > + varinfo_t uses = get_call_use_vi (t); > + make_any_offset_constraints (uses); > + make_constraint_to (uses->id, gimple_call_arg (t, 0)); > + /* No constraints are necessary for the return value. */ > + return true; > + } > + case BUILT_IN_OBJECT_SIZE: > + case BUILT_IN_CONSTANT_P: > + { > + /* No constraints are necessary for the return value or the > + arguments. */ > + return true; > + } > /* Trampolines are special - they set up passing the static > frame. */ > case BUILT_IN_INIT_TRAMPOLINE: > > -- Richard Biener SUSE LINUX GmbH, GF: Felix Imendoerffer, Jane Smithard, Graham Norton, HRB 21284 (AG Nuernberg)