From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 123842 invoked by alias); 28 May 2015 21:01:05 -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 123824 invoked by uid 89); 28 May 2015 21:01:04 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-0.1 required=5.0 tests=AWL,BAYES_00,FREEMAIL_FROM,KAM_STOCKGEN,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=no version=3.3.2 X-HELO: mail-ob0-f175.google.com Received: from mail-ob0-f175.google.com (HELO mail-ob0-f175.google.com) (209.85.214.175) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES128-GCM-SHA256 encrypted) ESMTPS; Thu, 28 May 2015 21:01:03 +0000 Received: by obbnx5 with SMTP id nx5so42715637obb.0 for ; Thu, 28 May 2015 14:01:01 -0700 (PDT) MIME-Version: 1.0 X-Received: by 10.182.126.40 with SMTP id mv8mr4228227obb.22.1432846861303; Thu, 28 May 2015 14:01:01 -0700 (PDT) Received: by 10.76.160.68 with HTTP; Thu, 28 May 2015 14:01:01 -0700 (PDT) In-Reply-To: References: <555E5376.3060706@redhat.com> <555EF018.2050309@redhat.com> Date: Thu, 28 May 2015 21:31:00 -0000 Message-ID: Subject: Re: [RFC][PATCH][X86_64] Eliminate PLT stubs for specified external functions via -fno-plt= From: "H.J. Lu" To: Sriraman Tallam Cc: Pedro Alves , Michael Matz , David Li , GCC Patches , Jan Hubicka Content-Type: text/plain; charset=UTF-8 X-IsSubscribed: yes X-SW-Source: 2015-05/txt/msg02700.txt.bz2 On Thu, May 28, 2015 at 1:54 PM, Sriraman Tallam wrote: > On Thu, May 28, 2015 at 12:05 PM, H.J. Lu wrote: >> On Thu, May 28, 2015 at 11:50 AM, Sriraman Tallam wrote: >>> On Thu, May 28, 2015 at 11:42 AM, H.J. Lu wrote: >>>> On Thu, May 28, 2015 at 11:34 AM, Sriraman Tallam wrote: >>>>> I have attached a patch that adds the new attribute "noplt". Please review. >>>>> >>>>> * config/i386/i386.c (avoid_plt_to_call): New function. >>>>> (ix86_output_call_insn): Generate indirect call for functions >>>>> marked with "noplt" attribute. >>>>> (attribute_spec ix86_attribute_): Define new attribute "noplt". >>>>> * doc/extend.texi: Document new attribute "noplt". >>>>> * gcc.target/i386/noplt-1.c: New testcase. >>>>> * gcc.target/i386/noplt-2.c: New testcase. >>>>> >>>> >>>> 2 comments: >>>> >>>> 1. Don't remove "%!" prefix before call/jmp. It is needed for MPX. >>>> 2. Don't you need to check >>>> >>>> && !TARGET_MACHO >>>> && !TARGET_SEH >>>> && !TARGET_PECOFF >>>> >>>> since it only works for ELF. >>> >>> Ok, I will make this change. OTOH, is it just better to piggy-back on >>> existing -fno-plt change by Alex in calls.c >>> and do this: >>> >>> Index: calls.c >>> =================================================================== >>> --- calls.c (revision 223720) >>> +++ calls.c (working copy) >>> @@ -226,9 +226,11 @@ prepare_call_address (tree fndecl_or_type, rtx fun >>> && targetm.small_register_classes_for_mode_p (FUNCTION_MODE)) >>> ? force_not_mem (memory_address (FUNCTION_MODE, funexp)) >>> : memory_address (FUNCTION_MODE, funexp)); >>> - else if (flag_pic && !flag_plt && fndecl_or_type >>> + else if (fndecl_or_type >>> && TREE_CODE (fndecl_or_type) == FUNCTION_DECL >>> - && !targetm.binds_local_p (fndecl_or_type)) >>> + && !targetm.binds_local_p (fndecl_or_type) >>> + && ((flag_pic && !flag_plt) >>> + || (lookup_attribute ("noplt", DECL_ATTRIBUTES(fndecl_or_type))))) >>> { >>> funexp = force_reg (Pmode, funexp); >>> } >>> >> >> Does it work on non-PIC calls? > > You are right, it doesnt work. I have attached the patch with the > changes you mentioned. > Since direct_p is true, do wee need + if (GET_CODE (call_op) != SYMBOL_REF + || SYMBOL_REF_LOCAL_P (call_op)) + return false; H.J.