From patchwork Thu Oct 29 16:08:46 2015 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Tom de Vries X-Patchwork-Id: 537935 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from sourceware.org (server1.sourceware.org [209.132.180.131]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id C28201402B3 for ; Fri, 30 Oct 2015 03:09:16 +1100 (AEDT) Authentication-Results: ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=gcc.gnu.org header.i=@gcc.gnu.org header.b=Ch14xiRR; dkim-atps=neutral DomainKey-Signature: a=rsa-sha1; c=nofws; d=gcc.gnu.org; h=list-id :list-unsubscribe:list-archive:list-post:list-help:sender :subject:to:references:cc:from:message-id:date:mime-version :in-reply-to:content-type; q=dns; s=default; b=MaBr1MNApYQPNz54t TJHNf3oSNUtKbx8UMithP6NLD4IqcqXsf6hKuS+FNKuWhWBwk2G1nJuKDpeaOI05 NfPe06Vr172Leqt2Z18g3dDvXl+VXNJqjY6U9TXEMp6vqiAp+IRrdAt1nPw3iSO3 9hNKHz1RKV97zTd1i5TDK7d9IE= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=gcc.gnu.org; h=list-id :list-unsubscribe:list-archive:list-post:list-help:sender :subject:to:references:cc:from:message-id:date:mime-version :in-reply-to:content-type; s=default; bh=6cSsMagQU9+ZEFQiimAbvhy RZxE=; b=Ch14xiRRZaWxFu6OYhWDd5zbJy91wmV1mUp0JIav2HQ7f8K3Tdu32na ksQwsTVGp7DuDrUBl9IbdoyqyEriBWTJvil4smfHVEkyA9Wbvd0zGPThEViqcE4P QatFWohlLFpweAadRJ1ztmbL637+yyBUhUrrw66IGS86//OKi/0Q= Received: (qmail 17194 invoked by alias); 29 Oct 2015 16:09:08 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Delivered-To: mailing list gcc-patches@gcc.gnu.org Received: (qmail 17183 invoked by uid 89); 29 Oct 2015 16:09:07 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.0 required=5.0 tests=AWL, BAYES_00, RP_MATCHES_RCVD, SPF_PASS autolearn=ham version=3.3.2 X-HELO: fencepost.gnu.org Received: from fencepost.gnu.org (HELO fencepost.gnu.org) (208.118.235.10) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-SHA encrypted) ESMTPS; Thu, 29 Oct 2015 16:09:02 +0000 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60829) by fencepost.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:256) (Exim 4.82) (envelope-from ) id 1Zrpl5-0003P4-TB for gcc-patches@gnu.org; Thu, 29 Oct 2015 12:08:59 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Zrpl1-0002q1-A3 for gcc-patches@gnu.org; Thu, 29 Oct 2015 12:08:59 -0400 Received: from relay1.mentorg.com ([192.94.38.131]:60878) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Zrpl1-0002pc-0i for gcc-patches@gnu.org; Thu, 29 Oct 2015 12:08:55 -0400 Received: from nat-ies.mentorg.com ([192.94.31.2] helo=SVR-IES-FEM-02.mgc.mentorg.com) by relay1.mentorg.com with esmtp id 1Zrpky-0002Mx-QN from Tom_deVries@mentor.com ; Thu, 29 Oct 2015 09:08:53 -0700 Received: from [127.0.0.1] (137.202.0.76) by SVR-IES-FEM-02.mgc.mentorg.com (137.202.0.106) with Microsoft SMTP Server id 14.3.224.2; Thu, 29 Oct 2015 16:08:50 +0000 Subject: Re: [PATCH, 1/6] Simplify constraint handling To: Richard Biener References: <562E0CF5.8000606@mentor.com> <562E5381.5@mentor.com> <562F26E2.40906@mentor.com> <562F6D1A.4010001@mentor.com> <562F711F.80900@mentor.com> <5630F242.7040806@mentor.com> <56320D9B.4070006@mentor.com> CC: Richard Biener , "gcc-patches@gnu.org" From: Tom de Vries Message-ID: <5632448E.5030509@mentor.com> Date: Thu, 29 Oct 2015 17:08:46 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: X-detected-operating-system: by eggs.gnu.org: Windows NT kernel [generic] [fuzzy] X-Received-From: 192.94.38.131 On 29/10/15 14:12, Richard Biener wrote: > On Thu, 29 Oct 2015, Tom de Vries wrote: > >> >On 29/10/15 12:13, Richard Biener wrote: >>> > >On Wed, 28 Oct 2015, Tom de Vries wrote: >>> > > >>>>> > > > >On 28/10/15 16:35, Richard Biener wrote: >>>>>>> > > > > > >On Tue, 27 Oct 2015, Tom de Vries wrote: >>>>>>> > > > > > > >>>>>>>>> > > > > > > > >On 27/10/15 13:24, Tom de Vries wrote: >>>>>>>>>>> > > > > > > > > > >Thinking it over a bit more, I realized the constraint >>>>>>> > > > > > >handling started >>>>>>>>>>> > > > > > > > > > >to be messy. I've reworked the patch series to simplify that >>>>>>> > > > > > >first. >>>>>>>>>>> > > > > > > > > > > >>>>>>>>>>> > > > > > > > > > > 1 Simplify constraint handling >>>>>>>>>>> > > > > > > > > > > 2 Rename make_restrict_var_constraints to >>>>>>>>>>> > > > > > > > > > >make_param_constraints >>>>>>>>>>> > > > > > > > > > > 3 Add recursion to make_param_constraints >>>>>>>>>>> > > > > > > > > > > 4 Add handle_param parameter to >>>>>>> > > > > > >create_variable_info_for_1 >>>>>>>>>>> > > > > > > > > > > 5 Handle recursive restrict pointer in >>>>>>>>>>> > > > > > > > > > >create_variable_info_for_1 >>>>>>>>>>> > > > > > > > > > > 6 Handle restrict struct fields recursively >>>>>>>>>>> > > > > > > > > > > >>>>>>>>>>> > > > > > > > > > >Currently doing bootstrap and regtest on x86_64. >>>>>>>>>>> > > > > > > > > > > >>>>>>>>>>> > > > > > > > > > >I'll repost the patch series in reply to this message. >>>>>>>>> > > > > > > > > >>>>>>>>> > > > > > > > >This patch gets rid of this bit of code in >>>>>> > > > > >intra_create_variable_infos: >>>>>>>>> > > > > > > > >... >>>>>>>>> > > > > > > > > if (restrict_pointer_p) >>>>>>>>> > > > > > > > > make_constraint_from_global_restrict (p, "PARM_RESTRICT"); >>>>>>>>> > > > > > > > > else >>>>>>>>> > > > > > > > >.. >>>>>>>>> > > > > > > > > >>>>>>>>> > > > > > > > >I already proposed to remove it here ( >>>>>>>>> > > > > > > > >https://gcc.gnu.org/ml/gcc-patches/2015-10/msg02426.html ) but >>>>>> > > > > >there is a >>>>>>>>> > > > > > > > >problem with that approach: It can happen that restrict_pointer_p >>>>>> > > > > >is true, >>>>>>>>> > > > > > > > >but >>>>>>>>> > > > > > > > >p->only_restrict_pointers is false. This happens with fipa-pta, >>>>>> > > > > >when >>>>>>>>> > > > > > > > >create_function_info_for created a varinfo for the parameter >>>>>> > > > > >before >>>>>>>>> > > > > > > > >intra_create_variable_infos was called. >>>>>>>>> > > > > > > > > >>>>>>>>> > > > > > > > >The patch handles that case now by setting >>>>>> > > > > >p->only_restrict_pointers. >>>>>>> > > > > > > >>>>>>> > > > > > >Hmm, but ... restrict only has an effect in non-IPA mode. >>>>> > > > > >>>>> > > > >Indeed, I also realized that by now. >>>>> > > > > >>>>> > > > >I wrote attached patch to make that explicit and simplify fipa-pta. >>>>> > > > > >>>>> > > > >OK for trunk if bootstrap and reg-test succeeds? >> > >> >First, there was an error in the patch, it tested for flag_ipa_pta (so it also >> >affected ealias), but it was supposed to test for in_ipa mode. That is fixed >> >in attached version. >> > >>> > >I don't see the patch simplifies anything but only removes spurious >>> > >settings by adding IMHO redundant checks. >> > >> >Consider testcase: >> >... >> >int __attribute__((noinline, noclone)) >> >foo (int *__restrict__ a, int *__restrict__ b) >> >{ >> > *a = 1; >> > *b = 2; >> >} >> > >> >int __attribute__((noinline, noclone)) >> >bar (int *a, int *b) >> >{ >> > foo (a, b); >> >} >> >... >> > >> >The impact of this patch in the pta dump (focusing on the constraints bit) is: >> >... >> > Generating constraints for foo (foo) >> > >> >-foo.arg0 = &PARM_NOALIAS(20) >> >-PARM_NOALIAS(20) = NONLOCAL >> >-foo.arg1 = &PARM_NOALIAS(21) >> >-PARM_NOALIAS(21) = NONLOCAL >> >+foo.arg0 = &NONLOCAL >> >+foo.arg1 = &NONLOCAL >> >... >> > >> >That's the kind of simplifications I'm trying to achieve. > Yes, but as I said we should refactor things to avoid calling > the intra constraints generation from the IPA path. Ah, I see. So, like this? OK for trunk if bootstrap and reg-test succeeds? Thanks, - Tom Add initial constraints in create_function_info_for 2015-10-29 Tom de Vries * tree-ssa-structalias.c (ipa_pta_execute): Add extra arg to call to create_function_info_for. Dump constraints generated during create_function_info_for. Move intra_create_variable_infos call and function-return-values-escape bit to ... (create_function_info_for): ... here, and merge intra_create_variable_infos call with argument loop. Add and handle nonlocal_p parameter. --- gcc/tree-ssa-structalias.c | 94 ++++++++++++++++++++++++++++------------------ 1 file changed, 58 insertions(+), 36 deletions(-) diff --git a/gcc/tree-ssa-structalias.c b/gcc/tree-ssa-structalias.c index 3bef607..3a0891c 100644 --- a/gcc/tree-ssa-structalias.c +++ b/gcc/tree-ssa-structalias.c @@ -5421,10 +5421,12 @@ count_num_arguments (tree decl, bool *is_varargs) } /* Creation function node for DECL, using NAME, and return the index - of the variable we've created for the function. */ + of the variable we've created for the function. If NONLOCAL_p, create + initial constraints. */ static varinfo_t -create_function_info_for (tree decl, const char *name, bool add_id) +create_function_info_for (tree decl, const char *name, bool add_id, + bool nonlocal_p) { struct function *fn = DECL_STRUCT_FUNCTION (decl); varinfo_t vi, prev_vi; @@ -5536,6 +5538,28 @@ create_function_info_for (tree decl, const char *name, bool add_id) insert_vi_for_tree (DECL_RESULT (decl), resultvi); } + /* We also need to make function return values escape. Nothing + escapes by returning from main though. */ + if (nonlocal_p + && !MAIN_NAME_P (DECL_NAME (decl))) + { + varinfo_t fi, rvi; + fi = lookup_vi_for_tree (decl); + rvi = first_vi_for_offset (fi, fi_result); + if (rvi && rvi->offset == fi_result) + { + struct constraint_expr includes; + struct constraint_expr var; + includes.var = escaped_id; + includes.offset = 0; + includes.type = SCALAR; + var.var = rvi->id; + var.offset = 0; + var.type = SCALAR; + process_constraint (new_constraint (includes, var)); + } + } + /* Set up variables for each argument. */ arg = DECL_ARGUMENTS (decl); for (i = 0; i < num_args; i++) @@ -5562,6 +5586,11 @@ create_function_info_for (tree decl, const char *name, bool add_id) gcc_assert (prev_vi->offset < argvi->offset); prev_vi->next = argvi->id; prev_vi = argvi; + + if (nonlocal_p + && argvi->may_have_pointers) + make_constraint_from (argvi, nonlocal_id); + if (arg) { insert_vi_for_tree (arg, argvi); @@ -7317,8 +7346,34 @@ ipa_pta_execute (void) gcc_assert (!node->clone_of); + /* For externally visible or attribute used annotated functions use + local constraints for their arguments. + For local functions we see all callers and thus do not need initial + constraints for parameters. */ + bool nonlocal_p = (node->used_from_other_partition + || node->externally_visible + || node->force_output + || node->address_taken); + vi = create_function_info_for (node->decl, - alias_get_name (node->decl), false); + alias_get_name (node->decl), false, + nonlocal_p); + if (dump_file + && from != constraints.length ()) + { + fprintf (dump_file, + "Generating intial constraints for %s", node->name ()); + if (DECL_ASSEMBLER_NAME_SET_P (node->decl)) + fprintf (dump_file, " (%s)", + IDENTIFIER_POINTER + (DECL_ASSEMBLER_NAME (node->decl))); + fprintf (dump_file, "\n\n"); + dump_constraints (dump_file, from); + fprintf (dump_file, "\n"); + + from = constraints.length (); + } + node->call_for_symbol_thunks_and_aliases (associate_varinfo_to_alias, vi, true); } @@ -7365,39 +7420,6 @@ ipa_pta_execute (void) func = DECL_STRUCT_FUNCTION (node->decl); gcc_assert (cfun == NULL); - /* For externally visible or attribute used annotated functions use - local constraints for their arguments. - For local functions we see all callers and thus do not need initial - constraints for parameters. */ - if (node->used_from_other_partition - || node->externally_visible - || node->force_output - || node->address_taken) - { - intra_create_variable_infos (func); - - /* We also need to make function return values escape. Nothing - escapes by returning from main though. */ - if (!MAIN_NAME_P (DECL_NAME (node->decl))) - { - varinfo_t fi, rvi; - fi = lookup_vi_for_tree (node->decl); - rvi = first_vi_for_offset (fi, fi_result); - if (rvi && rvi->offset == fi_result) - { - struct constraint_expr includes; - struct constraint_expr var; - includes.var = escaped_id; - includes.offset = 0; - includes.type = SCALAR; - var.var = rvi->id; - var.offset = 0; - var.type = SCALAR; - process_constraint (new_constraint (includes, var)); - } - } - } - /* Build constriants for the function body. */ FOR_EACH_BB_FN (bb, func) { -- 1.9.1