From patchwork Fri Apr 8 21:49:20 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Koenig X-Patchwork-Id: 90430 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]) by ozlabs.org (Postfix) with SMTP id 855AFB6F7D for ; Sat, 9 Apr 2011 07:49:35 +1000 (EST) Received: (qmail 9698 invoked by alias); 8 Apr 2011 21:49:33 -0000 Received: (qmail 9679 invoked by uid 22791); 8 Apr 2011 21:49:32 -0000 X-SWARE-Spam-Status: No, hits=-0.9 required=5.0 tests=AWL, BAYES_00, RCVD_IN_DNSWL_NONE, T_FRT_FREE, T_RP_MATCHES_RCVD X-Spam-Check-By: sourceware.org Received: from cc-smtpout2.netcologne.de (HELO cc-smtpout2.netcologne.de) (89.1.8.212) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Fri, 08 Apr 2011 21:49:26 +0000 Received: from cc-smtpin3.netcologne.de (cc-smtpin3.netcologne.de [89.1.8.203]) by cc-smtpout2.netcologne.de (Postfix) with ESMTP id 55AA01279A; Fri, 8 Apr 2011 23:49:24 +0200 (CEST) Received: from [192.168.0.197] (xdsl-84-44-177-184.netcologne.de [84.44.177.184]) by cc-smtpin3.netcologne.de (Postfix) with ESMTPSA id 94D6311E81; Fri, 8 Apr 2011 23:49:20 +0200 (CEST) Message-ID: <4D9F82E0.5000504@netcologne.de> Date: Fri, 08 Apr 2011 23:49:20 +0200 From: Thomas Koenig User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; de; rv:1.9.2.14) Gecko/20110221 SUSE/3.1.8 Thunderbird/3.1.8 MIME-Version: 1.0 To: Mikael Morin CC: fortran@gcc.gnu.org, Daniel Kraft , gcc-patches Subject: Re: [patch, fortran] More control over front end optimization References: <4D9E1168.50908@netcologne.de> <4D9E1596.9020707@domob.eu> <201104072235.01369.mikael.morin@sfr.fr> In-Reply-To: <201104072235.01369.mikael.morin@sfr.fr> 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 Hello Mikael and Daniel, thanks for the reviews. Here is what I committed as rev. 172215. I tried to be a little bit more specific in the doc, but couldn't think of a better name for the options without trying to win a prize for Gcc's longest option name. Thomas 2011-04-08 Thomas Koenig PR fortran/48448 * gfortran.h (gfc_option_t): Add warn_function_elimination and flag_frontend_optimize. * lang.opt (Wfunction-elimination): Add. (ffrontend-optimize): Add. * invoke.texi: Add documentation for -Wfunction-elimination and -ffrontend-optimize. Add -faggressive-function-elimination to list of code generation options. * frontend-passes.c (gfc_run_passes): Run optimizations if flag_frontend_optimize is set. (warn_function_elimination): New function. (cfe_expr_0): Call it if requested to do so. * options.c (gfc_init_options): Initiate warn_function_elimination and flag_frontend_optimize. (gfc_post_options): Set flag_frontend_optimize if not specified by user, depending on the optimization level. (gfc_handle_option): Handle -Wfunction-elimination and -ffrontend-optimize. 2011-04-08 Thomas Koenig PR fortran/48448 * gfortran.dg/function_optimize_5.f90: New test. Index: gfortran.h =================================================================== --- gfortran.h (Revision 172058) +++ gfortran.h (Arbeitskopie) @@ -2180,6 +2180,7 @@ typedef struct int warn_ampersand; int gfc_warn_conversion; int warn_conversion_extra; + int warn_function_elimination; int warn_implicit_interface; int warn_implicit_procedure; int warn_line_truncation; @@ -2234,6 +2235,7 @@ typedef struct int flag_protect_parens; int flag_realloc_lhs; int flag_aggressive_function_elimination; + int flag_frontend_optimize; int fpe; int rtcheck; Index: lang.opt =================================================================== --- lang.opt (Revision 172058) +++ lang.opt (Arbeitskopie) @@ -222,6 +222,10 @@ Wconversion-extra Fortran Warning Warn about most implicit conversions +Wfunction-elimination +Fortran Warning +Warn about function call elimination + Wimplicit-interface Fortran Warning Warn about calls with implicit interface @@ -414,6 +418,10 @@ ffree-line-length- Fortran RejectNegative Joined UInteger -ffree-line-length- Use n as character line width in free mode +ffrontend-optimize +Fortran +Enable front end optimization + fimplicit-none Fortran Specify that no implicit typing is allowed, unless overridden by explicit IMPLICIT statements Index: invoke.texi =================================================================== --- invoke.texi (Revision 172058) +++ invoke.texi (Arbeitskopie) @@ -139,7 +139,7 @@ and warnings}. -Wall -Waliasing -Wampersand -Warray-bounds -Wcharacter-truncation @gol -Wconversion -Wimplicit-interface -Wimplicit-procedure -Wline-truncation @gol -Wintrinsics-std -Wsurprising -Wno-tabs -Wunderflow -Wunused-parameter @gol --Wintrinsic-shadow -Wno-align-commons} +-Wintrinsic-shadow -Wno-align-commons -Wfunction-elimination} @item Debugging Options @xref{Debugging Options,,Options for debugging your program or GNU Fortran}. @@ -171,7 +171,8 @@ and warnings}. -fblas-matmul-limit=@var{n} -frecursive -finit-local-zero @gol -finit-integer=@var{n} -finit-real=@var{} @gol -finit-logical=@var{} -finit-character=@var{n} @gol --fno-align-commons -fno-protect-parens -frealloc-lhs} +-fno-align-commons -fno-protect-parens -frealloc-lhs @gol +-faggressive-function-elimination -ffrontend-optimize} @end table @menu @@ -859,6 +860,14 @@ By default, @command{gfortran} warns about any occ padded for proper alignment inside a @code{COMMON} block. This warning can be turned off via @option{-Wno-align-commons}. See also @option{-falign-commons}. +@item -Wfunction-elimination +@opindex @code{Wfunction-elimination} +@cindex function elimination +@cindex warnings, function elimination +Warn if any calls to functions are eliminated by the optimizations +enabled by the @option{-ffrontend-optimize} option. + + @item -Werror @opindex @code{Werror} @cindex warnings, to errors @@ -1482,8 +1491,19 @@ statements, regardless of whether these functions @smallexample a = f(b,c) + f(b,c) @end smallexample -there will only be a single call to @code{f}. +there will only be a single call to @code{f}. This option only works +if @option{-ffrontend-optimize} is in effect. +@item -ffrontend-optimize +@opindex @code{frontend-optimize} +@cindex Front-end optimization +This option performs front-end optimization, based on manipulating +parts the Fortran parse tree. Enabled by default by any @option{-O} +option. Optimizations enabled by this option include elimination of +identical function calls within expressions, removing unnecessary +calls to @code{TRIM} in comparisons and assignments and replacing +@code{TRIM(a)} with @code{a(1:LEN_TRIM(a)}. +It can be deselected by specifying @option{-fno-frontend-optimize}. @end table @xref{Code Gen Options,,Options for Code Generation Conventions, Index: frontend-passes.c =================================================================== --- frontend-passes.c (Revision 172058) +++ frontend-passes.c (Arbeitskopie) @@ -62,7 +62,7 @@ gfc_namespace *current_ns; void gfc_run_passes (gfc_namespace *ns) { - if (optimize) + if (gfc_option.flag_frontend_optimize) { expr_size = 20; expr_array = XNEWVEC(gfc_expr **, expr_size); @@ -283,6 +283,20 @@ create_var (gfc_expr * e) return result; } +/* Warn about function elimination. */ + +static void +warn_function_elimination (gfc_expr *e) +{ + if (e->expr_type != EXPR_FUNCTION) + return; + if (e->value.function.esym) + gfc_warning ("Removing call to function '%s' at %L", + e->value.function.esym->name, &(e->where)); + else if (e->value.function.isym) + gfc_warning ("Removing call to function '%s' at %L", + e->value.function.isym->name, &(e->where)); +} /* Callback function for the code walker for doing common function elimination. This builds up the list of functions in the expression and goes through them to detect duplicates, which it then replaces @@ -315,6 +329,10 @@ cfe_expr_0 (gfc_expr **e, int *walk_subtrees, { if (newvar == NULL) newvar = create_var (*(expr_array[i])); + + if (gfc_option.warn_function_elimination) + warn_function_elimination (*(expr_array[j])); + gfc_free (*(expr_array[j])); *(expr_array[j]) = gfc_copy_expr (newvar); } Index: options.c =================================================================== --- options.c (Revision 172058) +++ options.c (Arbeitskopie) @@ -99,6 +99,7 @@ gfc_init_options (unsigned int decoded_options_cou gfc_option.warn_array_temp = 0; gfc_option.gfc_warn_conversion = 0; gfc_option.warn_conversion_extra = 0; + gfc_option.warn_function_elimination = 0; gfc_option.warn_implicit_interface = 0; gfc_option.warn_line_truncation = 0; gfc_option.warn_surprising = 0; @@ -151,6 +152,7 @@ gfc_init_options (unsigned int decoded_options_cou gfc_option.flag_protect_parens = 1; gfc_option.flag_realloc_lhs = -1; gfc_option.flag_aggressive_function_elimination = 0; + gfc_option.flag_frontend_optimize = -1; gfc_option.fpe = 0; gfc_option.rtcheck = 0; @@ -418,6 +420,12 @@ gfc_post_options (const char **pfilename) if (pedantic && gfc_option.flag_whole_file) gfc_option.flag_whole_file = 2; + /* Optimization implies front end optimization, unless the user + specified it directly. */ + + if (gfc_option.flag_frontend_optimize == -1) + gfc_option.flag_frontend_optimize = optimize; + gfc_cpp_post_options (); /* FIXME: return gfc_cpp_preprocess_only (); @@ -610,6 +618,10 @@ gfc_handle_option (size_t scode, const char *arg, gfc_option.warn_conversion_extra = value; break; + case OPT_Wfunction_elimination: + gfc_option.warn_function_elimination = value; + break; + case OPT_Wimplicit_interface: gfc_option.warn_implicit_interface = value; break; @@ -979,6 +991,10 @@ gfc_handle_option (size_t scode, const char *arg, gfc_option.flag_aggressive_function_elimination = value; break; + case OPT_ffrontend_optimize: + gfc_option.flag_frontend_optimize = value; + break; + case OPT_fprotect_parens: gfc_option.flag_protect_parens = value; break;