| Message ID | 20190515124006.25840-6-christophe.lyon@st.com |
|---|---|
| State | New |
| Headers | show |
| Series | FDPIC ABI for ARM | expand |
Christophe Lyon <christophe.lyon@st.com> writes: > In FDPIC, we need to make sure __do_global_dtors_aux and frame_dummy > are referenced by their address, not by pointers to the function > descriptors. > > 2019-XX-XX Christophe Lyon <christophe.lyon@st.com> > Mickaël Guêné <mickael.guene@st.com> > > * libgcc/crtstuff.c: Add support for FDPIC. > > Change-Id: I0bc4b1232fbf3c69068fb23a1b9cafc895d141b1 > > diff --git a/libgcc/crtstuff.c b/libgcc/crtstuff.c > index 4927a9f..159b461 100644 > --- a/libgcc/crtstuff.c > +++ b/libgcc/crtstuff.c > @@ -429,9 +429,18 @@ __do_global_dtors_aux (void) > #ifdef FINI_SECTION_ASM_OP > CRT_CALL_STATIC_FUNCTION (FINI_SECTION_ASM_OP, __do_global_dtors_aux) > #elif defined (FINI_ARRAY_SECTION_ASM_OP) > +#if defined(__FDPIC__) > +__asm__( > + " .section .fini_array\n" > + " .align 2\n" > + " .word __do_global_dtors_aux\n" > +); > +asm (TEXT_SECTION_ASM_OP); > +#else /* defined(__FDPIC__) */ > static func_ptr __do_global_dtors_aux_fini_array_entry[] > __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(func_ptr)))) > = { __do_global_dtors_aux }; > +#endif /* defined(__FDPIC__) */ > #else /* !FINI_SECTION_ASM_OP && !FINI_ARRAY_SECTION_ASM_OP */ > static void __attribute__((used)) > __do_global_dtors_aux_1 (void) It'd be good to avoid hard-coding the pointer size. Would it work to do: __asm__("\t.equ\.t__do_global_dtors_aux_alias, __do_global_dtors_aux\n"); extern char __do_global_dtors_aux_alias; static void *__do_global_dtors_aux_fini_array_entry[] __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(void *)))) = { &__do_global_dtors_aux_alias }; ? Similarly for the init_array. AFAICT this and 02/21 are the only patches that aren't Arm-specific, is that right? Thanks, Richard
On Fri, 12 Jul 2019 at 08:06, Richard Sandiford <richard.sandiford@arm.com> wrote: > > Christophe Lyon <christophe.lyon@st.com> writes: > > In FDPIC, we need to make sure __do_global_dtors_aux and frame_dummy > > are referenced by their address, not by pointers to the function > > descriptors. > > > > 2019-XX-XX Christophe Lyon <christophe.lyon@st.com> > > Mickaël Guêné <mickael.guene@st.com> > > > > * libgcc/crtstuff.c: Add support for FDPIC. > > > > Change-Id: I0bc4b1232fbf3c69068fb23a1b9cafc895d141b1 > > > > diff --git a/libgcc/crtstuff.c b/libgcc/crtstuff.c > > index 4927a9f..159b461 100644 > > --- a/libgcc/crtstuff.c > > +++ b/libgcc/crtstuff.c > > @@ -429,9 +429,18 @@ __do_global_dtors_aux (void) > > #ifdef FINI_SECTION_ASM_OP > > CRT_CALL_STATIC_FUNCTION (FINI_SECTION_ASM_OP, __do_global_dtors_aux) > > #elif defined (FINI_ARRAY_SECTION_ASM_OP) > > +#if defined(__FDPIC__) > > +__asm__( > > + " .section .fini_array\n" > > + " .align 2\n" > > + " .word __do_global_dtors_aux\n" > > +); > > +asm (TEXT_SECTION_ASM_OP); > > +#else /* defined(__FDPIC__) */ > > static func_ptr __do_global_dtors_aux_fini_array_entry[] > > __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(func_ptr)))) > > = { __do_global_dtors_aux }; > > +#endif /* defined(__FDPIC__) */ > > #else /* !FINI_SECTION_ASM_OP && !FINI_ARRAY_SECTION_ASM_OP */ > > static void __attribute__((used)) > > __do_global_dtors_aux_1 (void) > > It'd be good to avoid hard-coding the pointer size. Would it work to do: > > __asm__("\t.equ\.t__do_global_dtors_aux_alias, __do_global_dtors_aux\n"); > extern char __do_global_dtors_aux_alias; > static void *__do_global_dtors_aux_fini_array_entry[] > __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(void *)))) > = { &__do_global_dtors_aux_alias }; > > ? Similarly for the init_array. > I'll take a look, thanks. > AFAICT this and 02/21 are the only patches that aren't Arm-specific, > is that right? Yes for compiler/libs changes. There are also testsuite changes that potentially include other targets in patches 16,17,18. Thanks, Christophe > Thanks, > Richard
On 12/07/2019 08:06, Richard Sandiford wrote: > Christophe Lyon <christophe.lyon@st.com> writes: >> In FDPIC, we need to make sure __do_global_dtors_aux and frame_dummy >> are referenced by their address, not by pointers to the function >> descriptors. >> >> 2019-XX-XX Christophe Lyon <christophe.lyon@st.com> >> Mickaël Guêné <mickael.guene@st.com> >> >> * libgcc/crtstuff.c: Add support for FDPIC. >> >> Change-Id: I0bc4b1232fbf3c69068fb23a1b9cafc895d141b1 >> >> diff --git a/libgcc/crtstuff.c b/libgcc/crtstuff.c >> index 4927a9f..159b461 100644 >> --- a/libgcc/crtstuff.c >> +++ b/libgcc/crtstuff.c >> @@ -429,9 +429,18 @@ __do_global_dtors_aux (void) >> #ifdef FINI_SECTION_ASM_OP >> CRT_CALL_STATIC_FUNCTION (FINI_SECTION_ASM_OP, __do_global_dtors_aux) >> #elif defined (FINI_ARRAY_SECTION_ASM_OP) >> +#if defined(__FDPIC__) >> +__asm__( >> + " .section .fini_array\n" >> + " .align 2\n" >> + " .word __do_global_dtors_aux\n" >> +); >> +asm (TEXT_SECTION_ASM_OP); >> +#else /* defined(__FDPIC__) */ >> static func_ptr __do_global_dtors_aux_fini_array_entry[] >> __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(func_ptr)))) >> = { __do_global_dtors_aux }; >> +#endif /* defined(__FDPIC__) */ >> #else /* !FINI_SECTION_ASM_OP && !FINI_ARRAY_SECTION_ASM_OP */ >> static void __attribute__((used)) >> __do_global_dtors_aux_1 (void) > > It'd be good to avoid hard-coding the pointer size. Would it work to do: > > __asm__("\t.equ\.t__do_global_dtors_aux_alias, __do_global_dtors_aux\n"); > extern char __do_global_dtors_aux_alias; > static void *__do_global_dtors_aux_fini_array_entry[] > __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(void *)))) > = { &__do_global_dtors_aux_alias }; > > ? Similarly for the init_array. > OK, done. > AFAICT this and 02/21 are the only patches that aren't Arm-specific, > is that right? > > Thanks, > Richard > . >
Christophe Lyon <christophe.lyon@st.com> writes: > On 12/07/2019 08:06, Richard Sandiford wrote: >> Christophe Lyon <christophe.lyon@st.com> writes: >>> In FDPIC, we need to make sure __do_global_dtors_aux and frame_dummy >>> are referenced by their address, not by pointers to the function >>> descriptors. >>> >>> 2019-XX-XX Christophe Lyon <christophe.lyon@st.com> >>> Mickaël Guêné <mickael.guene@st.com> >>> >>> * libgcc/crtstuff.c: Add support for FDPIC. >>> >>> Change-Id: I0bc4b1232fbf3c69068fb23a1b9cafc895d141b1 >>> >>> diff --git a/libgcc/crtstuff.c b/libgcc/crtstuff.c >>> index 4927a9f..159b461 100644 >>> --- a/libgcc/crtstuff.c >>> +++ b/libgcc/crtstuff.c >>> @@ -429,9 +429,18 @@ __do_global_dtors_aux (void) >>> #ifdef FINI_SECTION_ASM_OP >>> CRT_CALL_STATIC_FUNCTION (FINI_SECTION_ASM_OP, __do_global_dtors_aux) >>> #elif defined (FINI_ARRAY_SECTION_ASM_OP) >>> +#if defined(__FDPIC__) >>> +__asm__( >>> + " .section .fini_array\n" >>> + " .align 2\n" >>> + " .word __do_global_dtors_aux\n" >>> +); >>> +asm (TEXT_SECTION_ASM_OP); >>> +#else /* defined(__FDPIC__) */ >>> static func_ptr __do_global_dtors_aux_fini_array_entry[] >>> __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(func_ptr)))) >>> = { __do_global_dtors_aux }; >>> +#endif /* defined(__FDPIC__) */ >>> #else /* !FINI_SECTION_ASM_OP && !FINI_ARRAY_SECTION_ASM_OP */ >>> static void __attribute__((used)) >>> __do_global_dtors_aux_1 (void) >> >> It'd be good to avoid hard-coding the pointer size. Would it work to do: >> >> __asm__("\t.equ\.t__do_global_dtors_aux_alias, __do_global_dtors_aux\n"); >> extern char __do_global_dtors_aux_alias; >> static void *__do_global_dtors_aux_fini_array_entry[] >> __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(void *)))) >> = { &__do_global_dtors_aux_alias }; >> >> ? Similarly for the init_array. >> > OK, done. > >> AFAICT this and 02/21 are the only patches that aren't Arm-specific, >> is that right? >> >> Thanks, >> Richard >> . >> > > From ea0eee1ddeddef92277ae68eac4af28994c2902c Mon Sep 17 00:00:00 2001 > From: Christophe Lyon <christophe.lyon@linaro.org> > Date: Thu, 8 Feb 2018 11:12:52 +0100 > Subject: [ARM/FDPIC v6 05/24] [ARM] FDPIC: Fix __do_global_dtors_aux and > frame_dummy generation > MIME-Version: 1.0 > Content-Type: text/plain; charset=UTF-8 > Content-Transfer-Encoding: 8bit > > In FDPIC, we need to make sure __do_global_dtors_aux and frame_dummy > are referenced by their address, not by pointers to the function > descriptors. > > 2019-XX-XX Christophe Lyon <christophe.lyon@st.com> > Micka«l Guªn© <mickael.guene@st.com> > > libgcc/ > * libgcc/crtstuff.c: Add support for FDPIC. OK, thanks. Richard > > Change-Id: I0bc4b1232fbf3c69068fb23a1b9cafc895d141b1 > > diff --git a/libgcc/crtstuff.c b/libgcc/crtstuff.c > index 4927a9f..6659039 100644 > --- a/libgcc/crtstuff.c > +++ b/libgcc/crtstuff.c > @@ -429,9 +429,17 @@ __do_global_dtors_aux (void) > #ifdef FINI_SECTION_ASM_OP > CRT_CALL_STATIC_FUNCTION (FINI_SECTION_ASM_OP, __do_global_dtors_aux) > #elif defined (FINI_ARRAY_SECTION_ASM_OP) > +#if defined(__FDPIC__) > +__asm__("\t.equ\t__do_global_dtors_aux_alias, __do_global_dtors_aux\n"); > +extern char __do_global_dtors_aux_alias; > +static void *__do_global_dtors_aux_fini_array_entry[] > +__attribute__ ((__used__, section(".fini_array"), aligned(sizeof(void *)))) > + = { &__do_global_dtors_aux_alias }; > +#else /* defined(__FDPIC__) */ > static func_ptr __do_global_dtors_aux_fini_array_entry[] > __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(func_ptr)))) > = { __do_global_dtors_aux }; > +#endif /* defined(__FDPIC__) */ > #else /* !FINI_SECTION_ASM_OP && !FINI_ARRAY_SECTION_ASM_OP */ > static void __attribute__((used)) > __do_global_dtors_aux_1 (void) > @@ -473,9 +481,17 @@ frame_dummy (void) > #ifdef __LIBGCC_INIT_SECTION_ASM_OP__ > CRT_CALL_STATIC_FUNCTION (__LIBGCC_INIT_SECTION_ASM_OP__, frame_dummy) > #else /* defined(__LIBGCC_INIT_SECTION_ASM_OP__) */ > +#if defined(__FDPIC__) > +__asm__("\t.equ\t__frame_dummy_alias, frame_dummy\n"); > +extern char __frame_dummy_alias; > +static void *__frame_dummy_init_array_entry[] > +__attribute__ ((__used__, section(".init_array"), aligned(sizeof(void *)))) > + = { &__frame_dummy_alias }; > +#else /* defined(__FDPIC__) */ > static func_ptr __frame_dummy_init_array_entry[] > __attribute__ ((__used__, section(".init_array"), aligned(sizeof(func_ptr)))) > = { frame_dummy }; > +#endif /* defined(__FDPIC__) */ > #endif /* !defined(__LIBGCC_INIT_SECTION_ASM_OP__) */ > #endif /* USE_EH_FRAME_REGISTRY || USE_TM_CLONE_REGISTRY */
diff --git a/libgcc/crtstuff.c b/libgcc/crtstuff.c index 4927a9f..159b461 100644 --- a/libgcc/crtstuff.c +++ b/libgcc/crtstuff.c @@ -429,9 +429,18 @@ __do_global_dtors_aux (void) #ifdef FINI_SECTION_ASM_OP CRT_CALL_STATIC_FUNCTION (FINI_SECTION_ASM_OP, __do_global_dtors_aux) #elif defined (FINI_ARRAY_SECTION_ASM_OP) +#if defined(__FDPIC__) +__asm__( + " .section .fini_array\n" + " .align 2\n" + " .word __do_global_dtors_aux\n" +); +asm (TEXT_SECTION_ASM_OP); +#else /* defined(__FDPIC__) */ static func_ptr __do_global_dtors_aux_fini_array_entry[] __attribute__ ((__used__, section(".fini_array"), aligned(sizeof(func_ptr)))) = { __do_global_dtors_aux }; +#endif /* defined(__FDPIC__) */ #else /* !FINI_SECTION_ASM_OP && !FINI_ARRAY_SECTION_ASM_OP */ static void __attribute__((used)) __do_global_dtors_aux_1 (void) @@ -473,9 +482,18 @@ frame_dummy (void) #ifdef __LIBGCC_INIT_SECTION_ASM_OP__ CRT_CALL_STATIC_FUNCTION (__LIBGCC_INIT_SECTION_ASM_OP__, frame_dummy) #else /* defined(__LIBGCC_INIT_SECTION_ASM_OP__) */ +#if defined(__FDPIC__) +__asm__( + " .section .init_array\n" + " .align 2\n" + " .word frame_dummy\n" +); +asm (TEXT_SECTION_ASM_OP); +#else /* defined(__FDPIC__) */ static func_ptr __frame_dummy_init_array_entry[] __attribute__ ((__used__, section(".init_array"), aligned(sizeof(func_ptr)))) = { frame_dummy }; +#endif /* defined(__FDPIC__) */ #endif /* !defined(__LIBGCC_INIT_SECTION_ASM_OP__) */ #endif /* USE_EH_FRAME_REGISTRY || USE_TM_CLONE_REGISTRY */