From patchwork Thu Aug 8 16:31:30 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xinliang David Li X-Patchwork-Id: 265766 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 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "localhost", Issuer "www.qmailtoaster.com" (not verified)) by ozlabs.org (Postfix) with ESMTPS id 224CC2C00A9 for ; Fri, 9 Aug 2013 02:31:50 +1000 (EST) DomainKey-Signature: a=rsa-sha1; c=nofws; d=gcc.gnu.org; h=list-id :list-unsubscribe:list-archive:list-post:list-help:sender :mime-version:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; q=dns; s=default; b=lV4tWF/mygmlnkSSyY UQGuDHqZETdmXdoiX02W3yIQReUDtKJryfoAVHZroZ8Y+6cZuWFKlIksPpenJwTh q4ZhxYk7syVu+1agPuIQSf7Z/hRgckW7Da/olf6+xg10SZA5ymyUoXWjsOwY4hDo A2KxRVyxZGEX3Mp5LMfKi9SRQ= 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 :mime-version:in-reply-to:references:date:message-id:subject :from:to:cc:content-type; s=default; bh=TsrhkMCMRh5aD5yV1y7GYJtj auQ=; b=u752Uq8SNvI5Yk8FRDCZqXNa6VqXt9BBhlHebbZ2QlSBlplF+J1j58dh PC7uSVWVlxBMKjcdhILOTU47L/PuT8AFPAZIgq7LOTsDZx3wsEUtg2lyFpmmOQVs 4nBbgZ6wa382oXsPyYsUI/BA4LXRIgoR8HL5CNDwZnz+CVpuaj0= Received: (qmail 32356 invoked by alias); 8 Aug 2013 16:31:42 -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 32323 invoked by uid 89); 8 Aug 2013 16:31:41 -0000 X-Spam-SWARE-Status: No, score=-3.2 required=5.0 tests=AWL, BAYES_00, KHOP_THREADED, RCVD_IN_DNSWL_LOW, RCVD_IN_HOSTKARMA_YE, RDNS_NONE, SPF_PASS autolearn=ham version=3.3.1 Received: from Unknown (HELO mail-we0-f170.google.com) (74.125.82.170) by sourceware.org (qpsmtpd/0.84/v0.84-167-ge50287c) with ESMTP; Thu, 08 Aug 2013 16:31:39 +0000 Received: by mail-we0-f170.google.com with SMTP id w60so2774388wes.1 for ; Thu, 08 Aug 2013 09:31:30 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20120113; h=x-gm-message-state:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type; bh=l/UyRUvtTQ8WwguewQrilepGQnkSjSUBXNJk2Fa9SnM=; b=kUdP1jj/WaV1oqmtiop4IHCzVcroJHH7BWq1sEqrwCnq3XE+dXKU0f5mxbjA6oPIC/ SXlLmWRkBhnCuBytWCj/fctD5iCVX9/PNzIfme6NeU8+hz0rTNaKp4EYh1j27bwBCeww rdEhkPiBlsPdjy346QX2EU3pCwhR7uwb4HELs60Hn1TcqUDhkQMV5UTzcqlQkcEjLhAY HMPiPgfmhEQWY2O/NDJDZ3rNl3PEZtYINnMMHCiVX+dt2hb++tPX/RJ/djXbq5hU7qtB EDm4P+1y6fljj++uFcOZe/Wl+DsOzjbvJswtS4Fm4dwGz0tej4dEMLzd7J9cUj7WT39H wXyA== X-Gm-Message-State: ALoCoQnLV85kcTvY3Jyqv+D4qkTwV93fNXL47mkIYFdHgb95/ZMtwjWCTQ2nefhsSNvmBnyyRUXQuQICWVS1LDNKzjUA+GCFocOTrSmd0pbA0yONkQci+5tgvqaRLUemoj4LLDT+12dpc/d+AVjFA4jAVpDXPqhEVeQuGoywThB4K0glE26RvPCW0XV/Ba9iWxgHX/S5fA5gyQG+98BJUGSqDGdFBixRHQ== MIME-Version: 1.0 X-Received: by 10.194.248.130 with SMTP id ym2mr3868163wjc.61.1375979490782; Thu, 08 Aug 2013 09:31:30 -0700 (PDT) Received: by 10.180.212.81 with HTTP; Thu, 8 Aug 2013 09:31:30 -0700 (PDT) In-Reply-To: References: <20130805105658.GA5144@msticlxl57.ims.intel.com> <20130806094210.GC20805@kam.mff.cuni.cz> Date: Thu, 8 Aug 2013 09:31:30 -0700 Message-ID: Subject: Re: New parameters to control stringop expansion libcall strategy From: Xinliang David Li To: "Joseph S. Myers" Cc: Jan Hubicka , GCC Patches , Teresa Johnson X-Virus-Found: No Updated. thanks, David On Thu, Aug 8, 2013 at 8:18 AM, Joseph S. Myers wrote: > On Wed, 7 Aug 2013, Xinliang David Li wrote: > >> Updated patch attached (fixed header, buffer overflow, and warning --> >> error problems). > > You still have diagnostics starting with a capital letter, contrary to the > GNU Coding Standards. > > -- > Joseph S. Myers > joseph@codesourcery.com Index: testsuite/gcc.target/i386/memcpy-strategy-1.c =================================================================== --- testsuite/gcc.target/i386/memcpy-strategy-1.c (revision 0) +++ testsuite/gcc.target/i386/memcpy-strategy-1.c (revision 0) @@ -0,0 +1,12 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -march=atom -mmemcpy-strategy=vector_loop:-1:align" } */ +/* { dg-final { scan-assembler-times "movdqa" 8 { target { ! { ia32 } } } } } */ +/* { dg-final { scan-assembler-times "movdqa" 4 { target { ia32 } } } } */ + +char a[2048]; +char b[2048]; +void t (void) +{ + __builtin_memcpy (a, b, 2048); +} + Index: testsuite/gcc.target/i386/memcpy-strategy-2.c =================================================================== --- testsuite/gcc.target/i386/memcpy-strategy-2.c (revision 0) +++ testsuite/gcc.target/i386/memcpy-strategy-2.c (revision 0) @@ -0,0 +1,12 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -march=atom -mmemcpy-strategy=vector_loop:3000:align,libcall:-1:align" } */ +/* { dg-final { scan-assembler-times "movdqa" 8 { target { ! { ia32 } } } } } */ +/* { dg-final { scan-assembler-times "movdqa" 4 { target { ia32 } } } } */ + +char a[2048]; +char b[2048]; +void t (void) +{ + __builtin_memcpy (a, b, 2048); +} + Index: testsuite/gcc.target/i386/memset-strategy-1.c =================================================================== --- testsuite/gcc.target/i386/memset-strategy-1.c (revision 0) +++ testsuite/gcc.target/i386/memset-strategy-1.c (revision 0) @@ -0,0 +1,10 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -march=atom -mmemset-strategy=libcall:-1:align" } */ +/* { dg-final { scan-assembler-times "memset" 2 } } */ + +char a[2048]; +void t (void) +{ + __builtin_memset (a, 1, 2048); +} + Index: testsuite/gcc.target/i386/memcpy-strategy-3.c =================================================================== --- testsuite/gcc.target/i386/memcpy-strategy-3.c (revision 0) +++ testsuite/gcc.target/i386/memcpy-strategy-3.c (revision 0) @@ -0,0 +1,10 @@ +/* { dg-do compile } */ +/* { dg-options "-O2 -march=atom -mmemcpy-strategy=vector_loop:2000:align,libcall:-1:align" } */ +/* { dg-final { scan-assembler-times "memcpy" 2 } } */ + +char a[2048]; +char b[2048]; +void t (void) +{ + __builtin_memcpy (a, b, 2048); +} Index: doc/invoke.texi =================================================================== --- doc/invoke.texi (revision 201581) +++ doc/invoke.texi (working copy) @@ -652,6 +652,7 @@ Objective-C and Objective-C++ Dialects}. -mbmi2 -mrtm -mlwp -mthreads @gol -mno-align-stringops -minline-all-stringops @gol -minline-stringops-dynamically -mstringop-strategy=@var{alg} @gol +-mmemcpy-strategy=@var{strategy} -mmemset-strategy=@var{strategy} -mpush-args -maccumulate-outgoing-args -m128bit-long-double @gol -m96bit-long-double -mlong-double-64 -mlong-double-80 @gol -mregparm=@var{num} -msseregparm @gol @@ -14651,6 +14652,24 @@ Expand into an inline loop. Always use a library call. @end table +@item -mmemcpy-strategy=@var{strategy} +@opindex mmemcpy-strategy=@var{strategy} +Override the internal decision heuristic to decide if @code{__builtin_memcpy} +should be inlined and what inline algorithm to use when the expected size +of the copy operation is known. @var{strategy} +is a comma-separated list of @var{alg}:@var{max_size}:@var{dest_align} triplets. +@var{alg} is specified in @option{-mstringop-strategy}, @var{max_size} specifies +the max byte size with which inline algorithm @var{alg} is allowed. For the last +triplet, the @var{max_size} must be @code{-1}. The @var{max_size} of the triplets +in the list must be specified in increasing order. The minimal byte size for +@var{alg} is @code{0} for the first triplet and @code{@var{max_size} + 1} of the +preceding range. + +@item -mmemset-strategy=@var{strategy} +@opindex mmemset-strategy=@var{strategy} +The option is similar to @option{-mmemcpy-strategy=} except that it is to control +@code{__builtin_memset} expansion. + @item -momit-leaf-frame-pointer @opindex momit-leaf-frame-pointer Don't keep the frame pointer in a register for leaf functions. This Index: config/i386/stringop.def =================================================================== --- config/i386/stringop.def (revision 0) +++ config/i386/stringop.def (revision 0) @@ -0,0 +1,37 @@ +/* Definitions for stringop strategy for IA-32. + Copyright (C) 2013 Free Software Foundation, Inc. + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 3, or (at your option) +any later version. + +GCC is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GCC; see the files COPYING3. If not, +see . */ + +DEF_ENUM +DEF_ALG (no_stringop, no_stringop) +DEF_ENUM +DEF_ALG (libcall, libcall) +DEF_ENUM +DEF_ALG (rep_prefix_1_byte, rep_byte) +DEF_ENUM +DEF_ALG (rep_prefix_4_byte, rep_4byte) +DEF_ENUM +DEF_ALG (rep_prefix_8_byte, rep_8byte) +DEF_ENUM +DEF_ALG (loop_1_byte, byte_loop) +DEF_ENUM +DEF_ALG (loop, loop) +DEF_ENUM +DEF_ALG (unrolled_loop, unrolled_loop) +DEF_ENUM +DEF_ALG (vector_loop, vector_loop) Index: config/i386/stringop.opt =================================================================== --- config/i386/stringop.opt (revision 0) +++ config/i386/stringop.opt (revision 0) @@ -0,0 +1,31 @@ +/* Definitions for stringop option handling for IA-32. + Copyright (C) 2013 Free Software Foundation, Inc. + +This file is part of GCC. + +GCC is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 3, or (at your option) +any later version. + +GCC is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with GCC; see the files COPYING3. If not, +see . */ + +Enum(stringop_alg) String(rep_byte) Value(rep_prefix_1_byte) + +#undef DEF_ENUM +#define DEF_ENUM EnumValue + +#undef DEF_ALG +#define DEF_ALG(alg, name) Enum(stringop_alg) String(name) Value(alg) + +#include "stringop.def" + +#undef DEF_ENUM +#undef DEF_ALG Index: config/i386/i386-opts.h =================================================================== --- config/i386/i386-opts.h (revision 201581) +++ config/i386/i386-opts.h (working copy) @@ -28,15 +28,17 @@ see the files COPYING3 and COPYING.RUNTI /* Algorithm to expand string function with. */ enum stringop_alg { - no_stringop, - libcall, - rep_prefix_1_byte, - rep_prefix_4_byte, - rep_prefix_8_byte, - loop_1_byte, - loop, - unrolled_loop, - vector_loop +#undef DEF_ENUM +#define DEF_ENUM + +#undef DEF_ALG +#define DEF_ALG(alg, name) alg, + +#include "stringop.def" +last_alg + +#undef DEF_ENUM +#undef DEF_ALG }; /* Available call abi. */ Index: config/i386/i386.c =================================================================== --- config/i386/i386.c (revision 201582) +++ config/i386/i386.c (working copy) @@ -158,7 +158,7 @@ struct processor_costs ix86_size_cost = }; /* Processor costs (relative to an add) */ -static const +static struct processor_costs i386_cost = { /* 386 specific costs */ COSTS_N_INSNS (1), /* cost of an add instruction */ COSTS_N_INSNS (1), /* cost of a lea instruction */ @@ -228,7 +228,7 @@ struct processor_costs i386_cost = { /* 1, /* cond_not_taken_branch_cost. */ }; -static const +static struct processor_costs i486_cost = { /* 486 specific costs */ COSTS_N_INSNS (1), /* cost of an add instruction */ COSTS_N_INSNS (1), /* cost of a lea instruction */ @@ -300,7 +300,7 @@ struct processor_costs i486_cost = { /* 1, /* cond_not_taken_branch_cost. */ }; -static const +static struct processor_costs pentium_cost = { COSTS_N_INSNS (1), /* cost of an add instruction */ COSTS_N_INSNS (1), /* cost of a lea instruction */ @@ -370,7 +370,7 @@ struct processor_costs pentium_cost = { 1, /* cond_not_taken_branch_cost. */ }; -static const +static struct processor_costs pentiumpro_cost = { COSTS_N_INSNS (1), /* cost of an add instruction */ COSTS_N_INSNS (1), /* cost of a lea instruction */ @@ -449,7 +449,7 @@ struct processor_costs pentiumpro_cost = 1, /* cond_not_taken_branch_cost. */ }; -static const +static struct processor_costs geode_cost = { COSTS_N_INSNS (1), /* cost of an add instruction */ COSTS_N_INSNS (1), /* cost of a lea instruction */ @@ -520,7 +520,7 @@ struct processor_costs geode_cost = { 1, /* cond_not_taken_branch_cost. */ }; -static const +static struct processor_costs k6_cost = { COSTS_N_INSNS (1), /* cost of an add instruction */ COSTS_N_INSNS (2), /* cost of a lea instruction */ @@ -593,7 +593,7 @@ struct processor_costs k6_cost = { 1, /* cond_not_taken_branch_cost. */ }; -static const +static struct processor_costs athlon_cost = { COSTS_N_INSNS (1), /* cost of an add instruction */ COSTS_N_INSNS (2), /* cost of a lea instruction */ @@ -666,7 +666,7 @@ struct processor_costs athlon_cost = { 1, /* cond_not_taken_branch_cost. */ }; -static const +static struct processor_costs k8_cost = { COSTS_N_INSNS (1), /* cost of an add instruction */ COSTS_N_INSNS (2), /* cost of a lea instruction */ @@ -1267,7 +1267,7 @@ struct processor_costs btver2_cost = { 1, /* cond_not_taken_branch_cost. */ }; -static const +static struct processor_costs pentium4_cost = { COSTS_N_INSNS (1), /* cost of an add instruction */ COSTS_N_INSNS (3), /* cost of a lea instruction */ @@ -1338,7 +1338,7 @@ struct processor_costs pentium4_cost = { 1, /* cond_not_taken_branch_cost. */ }; -static const +static struct processor_costs nocona_cost = { COSTS_N_INSNS (1), /* cost of an add instruction */ COSTS_N_INSNS (1), /* cost of a lea instruction */ @@ -1411,7 +1411,7 @@ struct processor_costs nocona_cost = { 1, /* cond_not_taken_branch_cost. */ }; -static const +static struct processor_costs atom_cost = { COSTS_N_INSNS (1), /* cost of an add instruction */ COSTS_N_INSNS (1) + 1, /* cost of a lea instruction */ @@ -1558,7 +1558,7 @@ struct processor_costs slm_cost = { }; /* Generic64 should produce code tuned for Nocona and K8. */ -static const +static struct processor_costs generic64_cost = { COSTS_N_INSNS (1), /* cost of an add instruction */ /* On all chips taken into consideration lea is 2 cycles and more. With @@ -1637,7 +1637,7 @@ struct processor_costs generic64_cost = }; /* core_cost should produce code tuned for Core familly of CPUs. */ -static const +static struct processor_costs core_cost = { COSTS_N_INSNS (1), /* cost of an add instruction */ /* On all chips taken into consideration lea is 2 cycles and more. With @@ -1719,7 +1719,7 @@ struct processor_costs core_cost = { /* Generic32 should produce code tuned for PPro, Pentium4, Nocona, Athlon and K8. */ -static const +static struct processor_costs generic32_cost = { COSTS_N_INSNS (1), /* cost of an add instruction */ COSTS_N_INSNS (1) + 1, /* cost of a lea instruction */ @@ -2926,6 +2926,149 @@ ix86_debug_options (void) return; } + +static const char *stringop_alg_names[] = { +#define DEF_ENUM +#define DEF_ALG(alg, name) #name, +#include "stringop.def" +#undef DEF_ENUM +#undef DEF_ALG +}; + +/* Parse parameter string passed to -mmemcpy-strategy= or -mmemset-strategy=. + The string is of the following form (or comma separated list of it): + + strategy_alg:max_size:[align|noalign] + + where the full size range for the strategy is either [0, max_size] or + [min_size, max_size], in which min_size is the max_size + 1 of the + preceding range. The last size range must have max_size == -1. + + Examples: + + 1. + -mmemcpy-strategy=libcall:-1:noalign + + this is equivalent to (for known size memcpy) -mstringop-strategy=libcall + + + 2. + -mmemset-strategy=rep_8byte:16:noalign,vector_loop:2048:align,libcall:-1:noalign + + This is to tell the compiler to use the following strategy for memset + 1) when the expected size is between [1, 16], use rep_8byte strategy; + 2) when the size is between [17, 2048], use vector_loop; + 3) when the size is > 2048, use libcall. */ + +struct stringop_size_range +{ + int min; + int max; + stringop_alg alg; + bool noalign; +}; + +static void +ix86_parse_stringop_strategy_string (char *strategy_str, bool is_memset) +{ + const struct stringop_algs *default_algs; + stringop_size_range input_ranges[MAX_STRINGOP_ALGS]; + char *curr_range_str, *next_range_str; + int i = 0, n = 0; + + if (is_memset) + default_algs = &ix86_cost->memset[TARGET_64BIT != 0]; + else + default_algs = &ix86_cost->memcpy[TARGET_64BIT != 0]; + + curr_range_str = strategy_str; + + do + { + int mins, maxs; + stringop_alg alg; + char alg_name[128]; + char align[16]; + next_range_str = strchr (curr_range_str, ','); + if (next_range_str) + *next_range_str++ = '\0'; + + if (3 != sscanf (curr_range_str, "%20[^:]:%d:%10s", + alg_name, &maxs, align)) + { + error ("wrong arg %s to option %s", curr_range_str, + is_memset ? "-mmemset_strategy=" : "-mmemcpy_strategy="); + return; + } + + if (n > 0 && (maxs < (mins = input_ranges[n - 1].max + 1) && maxs != -1)) + { + error ("size ranges of option %s should be increasing", + is_memset ? "-mmemset_strategy=" : "-mmemcpy_strategy="); + return; + } + + for (i = 0; i < last_alg; i++) + { + if (!strcmp (alg_name, stringop_alg_names[i])) + { + alg = (stringop_alg) i; + break; + } + } + + if (i == last_alg) + { + error ("wrong stringop strategy name %s specified for option %s", + alg_name, + is_memset ? "-mmemset_strategy=" : "-mmemcpy_strategy="); + return; + } + + input_ranges[n].min = mins; + input_ranges[n].max = maxs; + input_ranges[n].alg = alg; + if (!strcmp (align, "align")) + input_ranges[n].noalign = false; + else if (!strcmp (align, "noalign")) + input_ranges[n].noalign = true; + else + { + error ("unknown alignment %s specified for option %s", + align, is_memset ? "-mmemset_strategy=" : "-mmemcpy_strategy="); + return; + } + n++; + curr_range_str = next_range_str; + } + while (curr_range_str); + + if (input_ranges[n - 1].max != -1) + { + error ("the max value for the last size range should be -1" + " for option %s", + is_memset ? "-mmemset_strategy=" : "-mmemcpy_strategy="); + return; + } + + if (n > MAX_STRINGOP_ALGS) + { + error ("too many size ranges specified in option %s", + is_memset ? "-mmemset_strategy=" : "-mmemcpy_strategy="); + return; + } + + /* Now override the default algs array. */ + for (i = 0; i < n; i++) + { + *const_cast(&default_algs->size[i].max) = input_ranges[i].max; + *const_cast(&default_algs->size[i].alg) + = input_ranges[i].alg; + *const_cast(&default_algs->size[i].noalign) + = input_ranges[i].noalign; + } +} + /* Override various settings based on options. If MAIN_ARGS_P, the options are from the command line, otherwise they are from @@ -4081,6 +4224,21 @@ ix86_option_override_internal (bool main /* Handle stack protector */ if (!global_options_set.x_ix86_stack_protector_guard) ix86_stack_protector_guard = TARGET_HAS_BIONIC ? SSP_GLOBAL : SSP_TLS; + + /* Handle -mmemcpy-strategy= and -mmemset-strategy= */ + if (ix86_tune_memcpy_strategy) + { + char *str = xstrdup (ix86_tune_memcpy_strategy); + ix86_parse_stringop_strategy_string (str, false); + free (str); + } + + if (ix86_tune_memset_strategy) + { + char *str = xstrdup (ix86_tune_memset_strategy); + ix86_parse_stringop_strategy_string (str, true); + free (str); + } } /* Implement the TARGET_OPTION_OVERRIDE hook. */ @@ -22964,6 +23122,7 @@ ix86_expand_movmem (rtx dst, rtx src, rt { case libcall: case no_stringop: + case last_alg: gcc_unreachable (); case loop_1_byte: need_zero_guard = true; @@ -23154,6 +23313,7 @@ ix86_expand_movmem (rtx dst, rtx src, rt { case libcall: case no_stringop: + case last_alg: gcc_unreachable (); case loop_1_byte: case loop: @@ -23365,6 +23525,7 @@ ix86_expand_setmem (rtx dst, rtx count_e { case libcall: case no_stringop: + case last_alg: gcc_unreachable (); case loop: need_zero_guard = true; @@ -23542,6 +23703,7 @@ ix86_expand_setmem (rtx dst, rtx count_e { case libcall: case no_stringop: + case last_alg: gcc_unreachable (); case loop_1_byte: case loop: Index: config/i386/i386.opt =================================================================== --- config/i386/i386.opt (revision 201582) +++ config/i386/i386.opt (working copy) @@ -316,6 +316,14 @@ mstack-arg-probe Target Report Mask(STACK_PROBE) Save Enable stack probing +mmemcpy-strategy= +Target RejectNegative Joined Var(ix86_tune_memcpy_strategy) +Specify memcpy expansion strategy when expected size is known + +mmemset-strategy= +Target RejectNegative Joined Var(ix86_tune_memset_strategy) +Specify memset expansion strategy when expected size is known + mstringop-strategy= Target RejectNegative Joined Enum(stringop_alg) Var(ix86_stringop_alg) Init(no_stringop) Chose strategy to generate stringop using