From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 104257 invoked by alias); 30 Aug 2019 09:24:26 -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 104201 invoked by uid 89); 30 Aug 2019 09:24:23 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-16.5 required=5.0 tests=AWL,BAYES_00,GIT_PATCH_0,GIT_PATCH_1,GIT_PATCH_2,GIT_PATCH_3,SPF_PASS autolearn=ham version=3.3.1 spammy=objections, HX-Languages-Length:5860 X-HELO: foss.arm.com Received: from foss.arm.com (HELO foss.arm.com) (217.140.110.172) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 30 Aug 2019 09:24:21 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 186CB344; Fri, 30 Aug 2019 02:24:20 -0700 (PDT) Received: from localhost (e121540-lin.manchester.arm.com [10.32.99.62]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 94DED3F718; Fri, 30 Aug 2019 02:24:19 -0700 (PDT) From: Richard Sandiford To: Christophe Lyon Mail-Followup-To: Christophe Lyon ,, richard.sandiford@arm.com Cc: Subject: Re: [ARM/FDPIC v5 01/21] [ARM] FDPIC: Add -mfdpic option support References: <20190515124006.25840-1-christophe.lyon@st.com> <20190515124006.25840-2-christophe.lyon@st.com> Date: Fri, 30 Aug 2019 10:06:00 -0000 In-Reply-To: (Christophe Lyon's message of "Thu, 29 Aug 2019 16:47:50 +0200") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain Content-Transfer-Encoding: 8bit X-IsSubscribed: yes X-SW-Source: 2019-08/txt/msg02054.txt.bz2 Christophe Lyon writes: > On 16/07/2019 12:11, Richard Sandiford wrote: >> [This isn't really something that should be reviewed under global >> reviewership, but if it's either that or nothing, I'll do it anyway...] >> >> Christophe Lyon writes: >>> 2019-XX-XX Christophe Lyon >>> Mickaël Guêné >>> >>> gcc/ >>> * config/arm/arm.opt: Add -mfdpic option. >>> * doc/invoke.texi: Add documentation for -mfdpic. >>> >>> Change-Id: I0eabd1d11c9406fd4a43c4333689ebebbfcc4fe8 >>> >>> diff --git a/gcc/config/arm/arm.opt b/gcc/config/arm/arm.opt >>> index 9067d49..2ed3bd5 100644 >>> --- a/gcc/config/arm/arm.opt >>> +++ b/gcc/config/arm/arm.opt >>> @@ -306,3 +306,7 @@ Cost to assume for a branch insn. >>> mgeneral-regs-only >>> Target Report RejectNegative Mask(GENERAL_REGS_ONLY) Save >>> Generate code which uses the core registers only (r0-r14). >>> + >>> +mfdpic >>> +Target Report Mask(FDPIC) >>> +Enable Function Descriptor PIC mode. >>> diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi >>> index 29585cf..805d7cc 100644 >>> --- a/gcc/doc/invoke.texi >>> +++ b/gcc/doc/invoke.texi >>> @@ -703,7 +703,8 @@ Objective-C and Objective-C++ Dialects}. >>> -mrestrict-it @gol >>> -mverbose-cost-dump @gol >>> -mpure-code @gol >>> --mcmse} >>> +-mcmse @gol >>> +-mfdpic} >>> >>> @emph{AVR Options} >>> @gccoptlist{-mmcu=@var{mcu} -mabsdata -maccumulate-args @gol >>> @@ -17912,6 +17913,23 @@ MOVT instruction. >>> Generate secure code as per the "ARMv8-M Security Extensions: Requirements on >>> Development Tools Engineering Specification", which can be found on >>> @url{http://infocenter.arm.com/help/topic/com.arm.doc.ecm0359818/ECM0359818_armv8m_security_extensions_reqs_on_dev_tools_1_0.pdf}. >>> + >>> +@item -mfdpic >>> +@itemx -mno-fdpic >>> +@opindex mfdpic >>> +@opindex mno-fdpic >>> +Select the FDPIC ABI, which uses function descriptors to represent >> >> Maybe "64-bit function descriptors"? Just a suggestion, might not be useful. >> >> OK with that change, thanks. > > OK, here is a new version, where I added a few words to explain that -static > is not supported. > > Thanks, > Christophe > >> >> Richard >> >>> +pointers to functions. When the compiler is configured for >>> +@code{arm-*-uclinuxfdpiceabi} targets, this option is on by default >>> +and implies @option{-fPIE} if none of the PIC/PIE-related options is >>> +provided. On other targets, it only enables the FDPIC-specific code >>> +generation features, and the user should explicitly provide the >>> +PIC/PIE-related options as needed. >>> + >>> +The opposite @option{-mno-fdpic} option is useful (and required) to >>> +build the Linux kernel using the same (@code{arm-*-uclinuxfdpiceabi}) >>> +toolchain as the one used to build the userland programs. >>> + >>> @end table >>> >>> @node AVR Options >> . >> > > From c936684e2b77ff5716bd8b67c617dcad088c72e0 Mon Sep 17 00:00:00 2001 > From: Christophe Lyon > Date: Thu, 8 Feb 2018 10:44:32 +0100 > Subject: [ARM/FDPIC v6 01/24] [ARM] FDPIC: Add -mfdpic option support > MIME-Version: 1.0 > Content-Type: text/plain; charset=UTF-8 > Content-Transfer-Encoding: 8bit > > 2019-XX-XX Christophe Lyon > Micka«l Guªn© > > gcc/ > * config/arm/arm.opt: Add -mfdpic option. > * doc/invoke.texi: Add documentation for -mfdpic. > > Change-Id: I05b98d6ae87c2b3fc04dd7fba415c730accdf33e > > diff --git a/gcc/config/arm/arm.opt b/gcc/config/arm/arm.opt > index 9067d49..2ed3bd5 100644 > --- a/gcc/config/arm/arm.opt > +++ b/gcc/config/arm/arm.opt > @@ -306,3 +306,7 @@ Cost to assume for a branch insn. > mgeneral-regs-only > Target Report RejectNegative Mask(GENERAL_REGS_ONLY) Save > Generate code which uses the core registers only (r0-r14). > + > +mfdpic > +Target Report Mask(FDPIC) > +Enable Function Descriptor PIC mode. > diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi > index 29585cf..b77fa06 100644 > --- a/gcc/doc/invoke.texi > +++ b/gcc/doc/invoke.texi > @@ -703,7 +703,8 @@ Objective-C and Objective-C++ Dialects}. > -mrestrict-it @gol > -mverbose-cost-dump @gol > -mpure-code @gol > --mcmse} > +-mcmse @gol > +-mfdpic} > > @emph{AVR Options} > @gccoptlist{-mmcu=@var{mcu} -mabsdata -maccumulate-args @gol > @@ -17912,6 +17913,27 @@ MOVT instruction. > Generate secure code as per the "ARMv8-M Security Extensions: Requirements on > Development Tools Engineering Specification", which can be found on > @url{http://infocenter.arm.com/help/topic/com.arm.doc.ecm0359818/ECM0359818_armv8m_security_extensions_reqs_on_dev_tools_1_0.pdf}. > + > +@item -mfdpic > +@itemx -mno-fdpic > +@opindex mfdpic > +@opindex mno-fdpic > +Select the FDPIC ABI, which uses 64-bit function descriptors to > +represent pointers to functions. When the compiler is configured for > +@code{arm-*-uclinuxfdpiceabi} targets, this option is on by default > +and implies @option{-fPIE} if none of the PIC/PIE-related options is > +provided. On other targets, it only enables the FDPIC-specific code > +generation features, and the user should explicitly provide the > +PIC/PIE-related options as needed. > + > +Note that static linking is not supported because it would still > +involve the dynamic linker when the program self-relocates. If such > +behaviour is acceptable, use -static and -Wl,-dynamic-linker options. "behavior". (To correct correct spelling :-/) OK with that change if there are no objections before the rest of the series is approved. > + > +The opposite @option{-mno-fdpic} option is useful (and required) to > +build the Linux kernel using the same (@code{arm-*-uclinuxfdpiceabi}) > +toolchain as the one used to build the userland programs. > + > @end table > > @node AVR Options