| Message ID | 20181011133518.17258-7-christophe.lyon@st.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | FDPIC ABI for ARM | expand |
On 11/10/18 14:34, Christophe Lyon wrote: > The main difference with existing support is that function addresses > are function descriptor addresses instead. This means that all code > dealing with function pointers now has to cope with function > descriptors instead. > > For the same reason, Linux kernel helpers can no longer be called by > dereferencing their address, so we implement the same functionality as > a regular function here. > > When restoring a function address, we also have to restore the FDPIC > register value (r9). > > 2018-XX-XX Christophe Lyon <christophe.lyon@st.com> > Mickaël Guêné <mickael.guene@st.com> > > gcc/ > * ginclude/unwind-arm-common.h (unwinder_cache): Add reserved5 > field. > (FDPIC_REGNUM): New define. > > libgcc/ > * config/arm/linux-atomic.c (__kernel_cmpxchg): Add FDPIC support. > (__kernel_dmb): Likewise. > (__fdpic_cmpxchg): New function. > (__fdpic_dmb): New function. > * config/arm/unwind-arm.h (gnu_Unwind_Find_got): New function. > (_Unwind_decode_typeinfo_ptr): Add FDPIC support. > * unwindo-arm-common.inc (UCB_PR_GOT): New. > (funcdesc_t): New struct. > (get_eit_entry): Add FDPIC support. > (unwind_phase2): Likewise. > (unwind_phase2_forced): Likewise. > (__gnu_Unwind_RaiseException): Likewise. > (__gnu_Unwind_Resume): Likewise. > (__gnu_Unwind_Backtrace): Likewise. > * unwind-pe.h (read_encoded_value_with_base): Likewise. > > libstdc++/ > * libsupc++/eh_personality.cc (get_ttype_entry): Add FDPIC > support. > > Change-Id: I517a49ff18fae21c686cd1c6008ea7974515b347 > > diff --git a/gcc/ginclude/unwind-arm-common.h b/gcc/ginclude/unwind-arm-common.h > index 8a1a919..f663891 100644 > --- a/gcc/ginclude/unwind-arm-common.h > +++ b/gcc/ginclude/unwind-arm-common.h > @@ -91,7 +91,7 @@ extern "C" { > _uw reserved2; /* Personality routine address */ > _uw reserved3; /* Saved callsite address */ > _uw reserved4; /* Forced unwind stop arg */ > - _uw reserved5; > + _uw reserved5; /* Personality routine GOT value in FDPIC mode. */ > } > unwinder_cache; > /* Propagation barrier cache (valid after phase 1): */ > @@ -247,4 +247,6 @@ typedef unsigned long _uleb128_t; > } /* extern "C" */ > #endif > > +#define FDPIC_REGNUM 9 Looking at the rest of this file, I think it can end up being included in user code. So you have to put predefines into the reserved namespace. Why do you need this here anyway? > + > #endif /* defined UNWIND_ARM_COMMON_H */ > diff --git a/libgcc/config/arm/linux-atomic.c b/libgcc/config/arm/linux-atomic.c > index d334c58..161d1ce 100644 > --- a/libgcc/config/arm/linux-atomic.c > +++ b/libgcc/config/arm/linux-atomic.c > @@ -25,11 +25,49 @@ see the files COPYING3 and COPYING.RUNTIME respectively. If not, see > > /* Kernel helper for compare-and-exchange. */ > typedef int (__kernel_cmpxchg_t) (int oldval, int newval, int *ptr); > +#if __FDPIC__ > +/* Non-FDPIC ABIs call __kernel_cmpxchg directly by dereferencing its > + address, but under FDPIC we would generate a broken call > + sequence. That's why we have to implement __kernel_cmpxchg and > + __kernel_dmb here: this way, the FDPIC call sequence works. */ > +#define __kernel_cmpxchg __fdpic_cmpxchg > +#else > #define __kernel_cmpxchg (*(__kernel_cmpxchg_t *) 0xffff0fc0) > +#endif > > /* Kernel helper for memory barrier. */ > typedef void (__kernel_dmb_t) (void); > +#if __FDPIC__ > +#define __kernel_dmb __fdpic_dmb > +#else > #define __kernel_dmb (*(__kernel_dmb_t *) 0xffff0fa0) > +#endif > + > +#if __FDPIC__ > +static int __fdpic_cmpxchg (int oldval, int newval, int *ptr) > +{ > + int result; > + > + asm volatile ("1: ldrex r3, [%[ptr]]\n\t" > + "subs r3, r3, %[oldval]\n\t" > + "itt eq\n\t" > + "strexeq r3, %[newval], [%[ptr]]\n\t" > + "teqeq r3, #1\n\t" > + "it eq\n\t" > + "beq 1b\n\t" > + "rsbs %[result], r3, #0\n\t" > + : [result] "=r" (result) > + : [oldval] "r" (oldval) , [newval] "r" (newval), [ptr] "r" (ptr) > + : "r3"); > + return result; > +} > + > +static void __fdpic_dmb () > +{ > + asm volatile ("dmb\n\t"); > +} > + The whole point of __kernel_dmb and __kernel_cmpxchg is that the kernel can map in a code sequence specific to the runtime CPU. This ensures that the right sequence is used for that CPU. This breaks that principle entirely. > +#endif > > /* Note: we implement byte, short and int versions of atomic operations using > the above kernel helpers; see linux-atomic-64bit.c for "long long" (64-bit) > diff --git a/libgcc/config/arm/unwind-arm.h b/libgcc/config/arm/unwind-arm.h > index 9f7d3f2..db5dfa2 100644 > --- a/libgcc/config/arm/unwind-arm.h > +++ b/libgcc/config/arm/unwind-arm.h > @@ -33,9 +33,31 @@ > /* Use IP as a scratch register within the personality routine. */ > #define UNWIND_POINTER_REG 12 > > +#define STR(x) #x > +#define XSTR(x) STR(x) > + > #ifdef __cplusplus > extern "C" { > #endif > +_Unwind_Ptr __attribute__((weak)) __gnu_Unwind_Find_got (_Unwind_Ptr); > + > +static inline _Unwind_Ptr gnu_Unwind_Find_got (_Unwind_Ptr ptr) > +{ > + _Unwind_Ptr res; > + > + if (__gnu_Unwind_Find_got) > + res = __gnu_Unwind_Find_got (ptr); > + else > + { > + asm volatile ("mov %[result], r" XSTR(FDPIC_REGNUM) > + : [result]"=r" (res) > + : > + :); > + } > + > + return res; > +} > + > /* Decode an R_ARM_TARGET2 relocation. */ > static inline _Unwind_Word > _Unwind_decode_typeinfo_ptr (_Unwind_Word base __attribute__ ((unused)), > @@ -48,7 +70,12 @@ extern "C" { > if (!tmp) > return 0; > > -#if (defined(linux) && !defined(__uClinux__)) || defined(__NetBSD__) \ > +#if __FDPIC__ > + /* For FDPIC, we store the offset of the GOT entry. */ > + /* So, first get GOT from dynamic linker and then use indirect access. */ > + tmp += gnu_Unwind_Find_got (ptr); > + tmp = *(_Unwind_Word *) tmp; > +#elif (defined(linux) && !defined(__uClinux__)) || defined(__NetBSD__) \ > || defined(__FreeBSD__) || defined(__fuchsia__) > /* Pc-relative indirect. */ > #define _GLIBCXX_OVERRIDE_TTYPE_ENCODING (DW_EH_PE_pcrel | DW_EH_PE_indirect) > diff --git a/libgcc/unwind-arm-common.inc b/libgcc/unwind-arm-common.inc > index 76f8fc3..7187edd 100644 > --- a/libgcc/unwind-arm-common.inc > +++ b/libgcc/unwind-arm-common.inc > @@ -62,6 +62,7 @@ __gnu_Unwind_Find_exidx (_Unwind_Ptr, int *); > #define UCB_PR_ADDR(ucbp) ((ucbp)->unwinder_cache.reserved2) > #define UCB_SAVED_CALLSITE_ADDR(ucbp) ((ucbp)->unwinder_cache.reserved3) > #define UCB_FORCED_STOP_ARG(ucbp) ((ucbp)->unwinder_cache.reserved4) > +#define UCB_PR_GOT(ucbp) ((ucbp)->unwinder_cache.reserved5) > > /* Unwind descriptors. */ > > @@ -85,6 +86,15 @@ typedef struct __EIT_entry > _uw content; > } __EIT_entry; > > +#ifdef __FDPIC__ > + > +/* Only used in FDPIC case. */ > +struct funcdesc_t { > + unsigned int ptr; > + unsigned int got; > +}; This isn't in GNU style. > +#endif > + > /* Assembly helper functions. */ > > /* Restore core register state. Never returns. */ > @@ -259,7 +269,21 @@ get_eit_entry (_Unwind_Control_Block *ucbp, _uw return_address) > { > /* One of the predefined standard routines. */ > _uw idx = (*(_uw *) ucbp->pr_cache.ehtp >> 24) & 0xf; > +#if __FDPIC__ > + { > + struct funcdesc_t *funcdesc > + = (struct funcdesc_t *) __gnu_unwind_get_pr_addr (idx); > + if (funcdesc) > + { > + UCB_PR_ADDR (ucbp) = funcdesc->ptr; > + UCB_PR_GOT (ucbp) = funcdesc->got; > + } > + else > + UCB_PR_ADDR (ucbp) = 0; > + } > +#else > UCB_PR_ADDR (ucbp) = __gnu_unwind_get_pr_addr (idx); > +#endif > if (UCB_PR_ADDR (ucbp) == 0) > { > /* Failed */ > @@ -270,6 +294,10 @@ get_eit_entry (_Unwind_Control_Block *ucbp, _uw return_address) > { > /* Execute region offset to PR */ > UCB_PR_ADDR (ucbp) = selfrel_offset31 (ucbp->pr_cache.ehtp); > +#if __FDPIC__ > + UCB_PR_GOT (ucbp) > + = (unsigned int) gnu_Unwind_Find_got ((_Unwind_Ptr) UCB_PR_ADDR (ucbp)); > +#endif > } > return _URC_OK; > } > @@ -291,14 +319,29 @@ unwind_phase2 (_Unwind_Control_Block * ucbp, phase2_vrs * vrs) > UCB_SAVED_CALLSITE_ADDR (ucbp) = VRS_PC(vrs); > > /* Call the pr to decide what to do. */ > +#if __FDPIC__ > + { > + volatile struct funcdesc_t funcdesc; > + funcdesc.ptr = UCB_PR_ADDR (ucbp); > + funcdesc.got = UCB_PR_GOT (ucbp); > + pr_result = ((personality_routine) &funcdesc) > + (_US_UNWIND_FRAME_STARTING, ucbp, (_Unwind_Context *) vrs); > + } > +#else > pr_result = ((personality_routine) UCB_PR_ADDR (ucbp)) > (_US_UNWIND_FRAME_STARTING, ucbp, (_Unwind_Context *) vrs); > +#endif > } > while (pr_result == _URC_CONTINUE_UNWIND); > > if (pr_result != _URC_INSTALL_CONTEXT) > abort(); > > +#if __FDPIC__ > + /* r9 could have been lost due to PLT jump. Restore correct value. */ > + vrs->core.r[FDPIC_REGNUM] = gnu_Unwind_Find_got (VRS_PC (vrs)); > +#endif > + > uw_restore_core_regs (vrs, &vrs->core); > } > > @@ -346,8 +389,18 @@ unwind_phase2_forced (_Unwind_Control_Block *ucbp, phase2_vrs *entry_vrs, > next_vrs = saved_vrs; > > /* Call the pr to decide what to do. */ > +#if __FDPIC__ > + { > + volatile struct funcdesc_t funcdesc; > + funcdesc.ptr = UCB_PR_ADDR (ucbp); > + funcdesc.got = UCB_PR_GOT (ucbp); > + pr_result = ((personality_routine) &funcdesc) > + (action, ucbp, (void *) &next_vrs); > + } > +#else > pr_result = ((personality_routine) UCB_PR_ADDR (ucbp)) > (action, ucbp, (void *) &next_vrs); > +#endif > > saved_vrs.prev_sp = VRS_SP (&next_vrs); > } > @@ -384,6 +437,11 @@ unwind_phase2_forced (_Unwind_Control_Block *ucbp, phase2_vrs *entry_vrs, > return _URC_FAILURE; > } > > +#if __FDPIC__ > + /* r9 could have been lost due to PLT jump. Restore correct value. */ > + saved_vrs.core.r[FDPIC_REGNUM] = gnu_Unwind_Find_got (VRS_PC (&saved_vrs)); > +#endif > + > uw_restore_core_regs (&saved_vrs, &saved_vrs.core); > } > > @@ -429,8 +487,18 @@ __gnu_Unwind_RaiseException (_Unwind_Control_Block * ucbp, > return _URC_FAILURE; > > /* Call the pr to decide what to do. */ > +#if __FDPIC__ > + { > + volatile struct funcdesc_t funcdesc; > + funcdesc.ptr = UCB_PR_ADDR (ucbp); > + funcdesc.got = UCB_PR_GOT (ucbp); > + pr_result = ((personality_routine) &funcdesc) > + (_US_VIRTUAL_UNWIND_FRAME, ucbp, (void *) &saved_vrs); > + } > +#else > pr_result = ((personality_routine) UCB_PR_ADDR (ucbp)) > (_US_VIRTUAL_UNWIND_FRAME, ucbp, (void *) &saved_vrs); > +#endif > } > while (pr_result == _URC_CONTINUE_UNWIND); > > @@ -488,13 +556,27 @@ __gnu_Unwind_Resume (_Unwind_Control_Block * ucbp, phase2_vrs * entry_vrs) > } > > /* Call the cached PR. */ > +#if __FDPIC__ > + { > + volatile struct funcdesc_t funcdesc; > + funcdesc.ptr = UCB_PR_ADDR (ucbp); > + funcdesc.got = UCB_PR_GOT (ucbp); > + pr_result = ((personality_routine) &funcdesc) > + (_US_UNWIND_FRAME_RESUME, ucbp, (_Unwind_Context *) entry_vrs); > + } > +#else > pr_result = ((personality_routine) UCB_PR_ADDR (ucbp)) > (_US_UNWIND_FRAME_RESUME, ucbp, (_Unwind_Context *) entry_vrs); > +#endif > > switch (pr_result) > { > case _URC_INSTALL_CONTEXT: > /* Upload the registers to enter the landing pad. */ > +#if __FDPIC__ > + /* r9 could have been lost due to PLT jump. Restore correct value. */ > + entry_vrs->core.r[FDPIC_REGNUM] = gnu_Unwind_Find_got (VRS_PC (entry_vrs)); > +#endif > uw_restore_core_regs (entry_vrs, &entry_vrs->core); > > case _URC_CONTINUE_UNWIND: > @@ -586,9 +668,20 @@ __gnu_Unwind_Backtrace(_Unwind_Trace_Fn trace, void * trace_argument, > } > > /* Call the pr to decide what to do. */ > +#if __FDPIC__ > + { > + volatile struct funcdesc_t funcdesc; > + funcdesc.ptr = UCB_PR_ADDR (ucbp); > + funcdesc.got = UCB_PR_GOT (ucbp); > + code = ((personality_routine) &funcdesc) > + (_US_VIRTUAL_UNWIND_FRAME | _US_FORCE_UNWIND, > + ucbp, (void *) &saved_vrs); > + } > +#else > code = ((personality_routine) UCB_PR_ADDR (ucbp)) > (_US_VIRTUAL_UNWIND_FRAME | _US_FORCE_UNWIND, > ucbp, (void *) &saved_vrs); > +#endif > } > while (code != _URC_END_OF_STACK > && code != _URC_FAILURE); > diff --git a/libgcc/unwind-pe.h b/libgcc/unwind-pe.h > index dd5ae95..9c5177f 100644 > --- a/libgcc/unwind-pe.h > +++ b/libgcc/unwind-pe.h > @@ -259,10 +259,27 @@ read_encoded_value_with_base (unsigned char encoding, _Unwind_Ptr base, > > if (result != 0) > { > +#if __FDPIC__ > + /* FDPIC relative addresses imply taking the GOT address > + into account. */ > + if ((encoding & DW_EH_PE_pcrel) && (encoding & DW_EH_PE_indirect)) > + { > + result += gnu_Unwind_Find_got ((_Unwind_Ptr) u); > + result = *(_Unwind_Internal_Ptr *) result; > + } > + else > + { > + result += ((encoding & 0x70) == DW_EH_PE_pcrel > + ? (_Unwind_Internal_Ptr) u : base); > + if (encoding & DW_EH_PE_indirect) > + result = *(_Unwind_Internal_Ptr *) result; > + } > +#else > result += ((encoding & 0x70) == DW_EH_PE_pcrel > ? (_Unwind_Internal_Ptr) u : base); > if (encoding & DW_EH_PE_indirect) > result = *(_Unwind_Internal_Ptr *) result; > +#endif > } > } > > diff --git a/libstdc++-v3/libsupc++/eh_personality.cc b/libstdc++-v3/libsupc++/eh_personality.cc > index 1b336c7..7b26b8d 100644 > --- a/libstdc++-v3/libsupc++/eh_personality.cc > +++ b/libstdc++-v3/libsupc++/eh_personality.cc > @@ -93,7 +93,15 @@ get_ttype_entry (lsda_header_info *info, _uleb128_t i) > _Unwind_Ptr ptr; > > i *= size_of_encoded_value (info->ttype_encoding); > - read_encoded_value_with_base (info->ttype_encoding, info->ttype_base, > + read_encoded_value_with_base ( > +#if __FDPIC__ > + /* Force these flags to nake sure to > + take the GOT into account. */ > + (DW_EH_PE_pcrel | DW_EH_PE_indirect), > +#else > + info->ttype_encoding, > +#endif > + info->ttype_base, > info->TType - i, &ptr); > > return reinterpret_cast<const std::type_info *>(ptr); > Nearly all of the above is outside of my comfort zone... I can't help feeling that there ought to be a less invasive way to do this, but without being particularly familiar with the code it's difficult to be sure. The last two files patched will need approval from a relevant component maintainer.
On Fri, 12 Oct 2018 at 13:37, Richard Earnshaw (lists) < Richard.Earnshaw@arm.com> wrote: > On 11/10/18 14:34, Christophe Lyon wrote: > > The main difference with existing support is that function addresses > > are function descriptor addresses instead. This means that all code > > dealing with function pointers now has to cope with function > > descriptors instead. > > > > For the same reason, Linux kernel helpers can no longer be called by > > dereferencing their address, so we implement the same functionality as > > a regular function here. > > > > When restoring a function address, we also have to restore the FDPIC > > register value (r9). > > > > 2018-XX-XX Christophe Lyon <christophe.lyon@st.com> > > Mickaël Guêné <mickael.guene@st.com> > > > > gcc/ > > * ginclude/unwind-arm-common.h (unwinder_cache): Add reserved5 > > field. > > (FDPIC_REGNUM): New define. > > > > libgcc/ > > * config/arm/linux-atomic.c (__kernel_cmpxchg): Add FDPIC support. > > (__kernel_dmb): Likewise. > > (__fdpic_cmpxchg): New function. > > (__fdpic_dmb): New function. > > * config/arm/unwind-arm.h (gnu_Unwind_Find_got): New function. > > (_Unwind_decode_typeinfo_ptr): Add FDPIC support. > > * unwindo-arm-common.inc (UCB_PR_GOT): New. > > (funcdesc_t): New struct. > > (get_eit_entry): Add FDPIC support. > > (unwind_phase2): Likewise. > > (unwind_phase2_forced): Likewise. > > (__gnu_Unwind_RaiseException): Likewise. > > (__gnu_Unwind_Resume): Likewise. > > (__gnu_Unwind_Backtrace): Likewise. > > * unwind-pe.h (read_encoded_value_with_base): Likewise. > > > > libstdc++/ > > * libsupc++/eh_personality.cc (get_ttype_entry): Add FDPIC > > support. > > > > Change-Id: I517a49ff18fae21c686cd1c6008ea7974515b347 > > > > diff --git a/gcc/ginclude/unwind-arm-common.h > b/gcc/ginclude/unwind-arm-common.h > > index 8a1a919..f663891 100644 > > --- a/gcc/ginclude/unwind-arm-common.h > > +++ b/gcc/ginclude/unwind-arm-common.h > > @@ -91,7 +91,7 @@ extern "C" { > > _uw reserved2; /* Personality routine address */ > > _uw reserved3; /* Saved callsite address */ > > _uw reserved4; /* Forced unwind stop arg */ > > - _uw reserved5; > > + _uw reserved5; /* Personality routine GOT value in FDPIC mode. > */ > > } > > unwinder_cache; > > /* Propagation barrier cache (valid after phase 1): */ > > @@ -247,4 +247,6 @@ typedef unsigned long _uleb128_t; > > } /* extern "C" */ > > #endif > > > > +#define FDPIC_REGNUM 9 > > Looking at the rest of this file, I think it can end up being included > in user code. So you have to put predefines into the reserved > namespace. Why do you need this here anyway? > > That was to address a comment I got on v2 of this patch: I was requested to avoid hardcoding "r9" in unwind-arm.h, and to use FDPIC_REGNUM. I needed the definition to be visible in both unwind-arm.h and unwind-arm-common.inc, but I moved it at a too high level. I'll fix this. > + > > #endif /* defined UNWIND_ARM_COMMON_H */ > > diff --git a/libgcc/config/arm/linux-atomic.c > b/libgcc/config/arm/linux-atomic.c > > index d334c58..161d1ce 100644 > > --- a/libgcc/config/arm/linux-atomic.c > > +++ b/libgcc/config/arm/linux-atomic.c > > @@ -25,11 +25,49 @@ see the files COPYING3 and COPYING.RUNTIME > respectively. If not, see > > > > /* Kernel helper for compare-and-exchange. */ > > typedef int (__kernel_cmpxchg_t) (int oldval, int newval, int *ptr); > > +#if __FDPIC__ > > +/* Non-FDPIC ABIs call __kernel_cmpxchg directly by dereferencing its > > + address, but under FDPIC we would generate a broken call > > + sequence. That's why we have to implement __kernel_cmpxchg and > > + __kernel_dmb here: this way, the FDPIC call sequence works. */ > > +#define __kernel_cmpxchg __fdpic_cmpxchg > > +#else > > #define __kernel_cmpxchg (*(__kernel_cmpxchg_t *) 0xffff0fc0) > > +#endif > > > > /* Kernel helper for memory barrier. */ > > typedef void (__kernel_dmb_t) (void); > > +#if __FDPIC__ > > +#define __kernel_dmb __fdpic_dmb > > +#else > > #define __kernel_dmb (*(__kernel_dmb_t *) 0xffff0fa0) > > +#endif > > + > > +#if __FDPIC__ > > +static int __fdpic_cmpxchg (int oldval, int newval, int *ptr) > > +{ > > + int result; > > + > > + asm volatile ("1: ldrex r3, [%[ptr]]\n\t" > > + "subs r3, r3, %[oldval]\n\t" > > + "itt eq\n\t" > > + "strexeq r3, %[newval], [%[ptr]]\n\t" > > + "teqeq r3, #1\n\t" > > + "it eq\n\t" > > + "beq 1b\n\t" > > + "rsbs %[result], r3, #0\n\t" > > + : [result] "=r" (result) > > + : [oldval] "r" (oldval) , [newval] "r" (newval), [ptr] "r" > (ptr) > > + : "r3"); > > + return result; > > +} > > + > > +static void __fdpic_dmb () > > +{ > > + asm volatile ("dmb\n\t"); > > +} > > + > > The whole point of __kernel_dmb and __kernel_cmpxchg is that the kernel > can map in a code sequence specific to the runtime CPU. This ensures > that the right sequence is used for that CPU. This breaks that > principle entirely. > > Right, I guess we had v7-only in mind. I'll check how we can fix that. > > +#endif > > > > /* Note: we implement byte, short and int versions of atomic operations > using > > the above kernel helpers; see linux-atomic-64bit.c for "long long" > (64-bit) > > diff --git a/libgcc/config/arm/unwind-arm.h > b/libgcc/config/arm/unwind-arm.h > > index 9f7d3f2..db5dfa2 100644 > > --- a/libgcc/config/arm/unwind-arm.h > > +++ b/libgcc/config/arm/unwind-arm.h > > @@ -33,9 +33,31 @@ > > /* Use IP as a scratch register within the personality routine. */ > > #define UNWIND_POINTER_REG 12 > > > > +#define STR(x) #x > > +#define XSTR(x) STR(x) > > + > > #ifdef __cplusplus > > extern "C" { > > #endif > > +_Unwind_Ptr __attribute__((weak)) __gnu_Unwind_Find_got (_Unwind_Ptr); > > + > > +static inline _Unwind_Ptr gnu_Unwind_Find_got (_Unwind_Ptr ptr) > > +{ > > + _Unwind_Ptr res; > > + > > + if (__gnu_Unwind_Find_got) > > + res = __gnu_Unwind_Find_got (ptr); > > + else > > + { > > + asm volatile ("mov %[result], r" XSTR(FDPIC_REGNUM) > > + : [result]"=r" (res) > > + : > > + :); > > + } > > + > > + return res; > > +} > > + > > /* Decode an R_ARM_TARGET2 relocation. */ > > static inline _Unwind_Word > > _Unwind_decode_typeinfo_ptr (_Unwind_Word base __attribute__ > ((unused)), > > @@ -48,7 +70,12 @@ extern "C" { > > if (!tmp) > > return 0; > > > > -#if (defined(linux) && !defined(__uClinux__)) || defined(__NetBSD__) \ > > +#if __FDPIC__ > > + /* For FDPIC, we store the offset of the GOT entry. */ > > + /* So, first get GOT from dynamic linker and then use indirect > access. */ > > + tmp += gnu_Unwind_Find_got (ptr); > > + tmp = *(_Unwind_Word *) tmp; > > +#elif (defined(linux) && !defined(__uClinux__)) || defined(__NetBSD__) \ > > || defined(__FreeBSD__) || defined(__fuchsia__) > > /* Pc-relative indirect. */ > > #define _GLIBCXX_OVERRIDE_TTYPE_ENCODING (DW_EH_PE_pcrel | > DW_EH_PE_indirect) > > diff --git a/libgcc/unwind-arm-common.inc b/libgcc/unwind-arm-common.inc > > index 76f8fc3..7187edd 100644 > > --- a/libgcc/unwind-arm-common.inc > > +++ b/libgcc/unwind-arm-common.inc > > @@ -62,6 +62,7 @@ __gnu_Unwind_Find_exidx (_Unwind_Ptr, int *); > > #define UCB_PR_ADDR(ucbp) ((ucbp)->unwinder_cache.reserved2) > > #define UCB_SAVED_CALLSITE_ADDR(ucbp) ((ucbp)->unwinder_cache.reserved3) > > #define UCB_FORCED_STOP_ARG(ucbp) ((ucbp)->unwinder_cache.reserved4) > > +#define UCB_PR_GOT(ucbp) ((ucbp)->unwinder_cache.reserved5) > > > > /* Unwind descriptors. */ > > > > @@ -85,6 +86,15 @@ typedef struct __EIT_entry > > _uw content; > > } __EIT_entry; > > > > +#ifdef __FDPIC__ > > + > > +/* Only used in FDPIC case. */ > > +struct funcdesc_t { > > + unsigned int ptr; > > + unsigned int got; > > +}; > > This isn't in GNU style. > > OK > > +#endif > > + > > /* Assembly helper functions. */ > > > > /* Restore core register state. Never returns. */ > > @@ -259,7 +269,21 @@ get_eit_entry (_Unwind_Control_Block *ucbp, _uw > return_address) > > { > > /* One of the predefined standard routines. */ > > _uw idx = (*(_uw *) ucbp->pr_cache.ehtp >> 24) & 0xf; > > +#if __FDPIC__ > > + { > > + struct funcdesc_t *funcdesc > > + = (struct funcdesc_t *) __gnu_unwind_get_pr_addr (idx); > > + if (funcdesc) > > + { > > + UCB_PR_ADDR (ucbp) = funcdesc->ptr; > > + UCB_PR_GOT (ucbp) = funcdesc->got; > > + } > > + else > > + UCB_PR_ADDR (ucbp) = 0; > > + } > > +#else > > UCB_PR_ADDR (ucbp) = __gnu_unwind_get_pr_addr (idx); > > +#endif > > if (UCB_PR_ADDR (ucbp) == 0) > > { > > /* Failed */ > > @@ -270,6 +294,10 @@ get_eit_entry (_Unwind_Control_Block *ucbp, _uw > return_address) > > { > > /* Execute region offset to PR */ > > UCB_PR_ADDR (ucbp) = selfrel_offset31 (ucbp->pr_cache.ehtp); > > +#if __FDPIC__ > > + UCB_PR_GOT (ucbp) > > + = (unsigned int) gnu_Unwind_Find_got ((_Unwind_Ptr) UCB_PR_ADDR > (ucbp)); > > +#endif > > } > > return _URC_OK; > > } > > @@ -291,14 +319,29 @@ unwind_phase2 (_Unwind_Control_Block * ucbp, > phase2_vrs * vrs) > > UCB_SAVED_CALLSITE_ADDR (ucbp) = VRS_PC(vrs); > > > > /* Call the pr to decide what to do. */ > > +#if __FDPIC__ > > + { > > + volatile struct funcdesc_t funcdesc; > > + funcdesc.ptr = UCB_PR_ADDR (ucbp); > > + funcdesc.got = UCB_PR_GOT (ucbp); > > + pr_result = ((personality_routine) &funcdesc) > > + (_US_UNWIND_FRAME_STARTING, ucbp, (_Unwind_Context *) vrs); > > + } > > +#else > > pr_result = ((personality_routine) UCB_PR_ADDR (ucbp)) > > (_US_UNWIND_FRAME_STARTING, ucbp, (_Unwind_Context *) vrs); > > +#endif > > } > > while (pr_result == _URC_CONTINUE_UNWIND); > > > > if (pr_result != _URC_INSTALL_CONTEXT) > > abort(); > > > > +#if __FDPIC__ > > + /* r9 could have been lost due to PLT jump. Restore correct value. > */ > > + vrs->core.r[FDPIC_REGNUM] = gnu_Unwind_Find_got (VRS_PC (vrs)); > > +#endif > > + > > uw_restore_core_regs (vrs, &vrs->core); > > } > > > > @@ -346,8 +389,18 @@ unwind_phase2_forced (_Unwind_Control_Block *ucbp, > phase2_vrs *entry_vrs, > > next_vrs = saved_vrs; > > > > /* Call the pr to decide what to do. */ > > +#if __FDPIC__ > > + { > > + volatile struct funcdesc_t funcdesc; > > + funcdesc.ptr = UCB_PR_ADDR (ucbp); > > + funcdesc.got = UCB_PR_GOT (ucbp); > > + pr_result = ((personality_routine) &funcdesc) > > + (action, ucbp, (void *) &next_vrs); > > + } > > +#else > > pr_result = ((personality_routine) UCB_PR_ADDR (ucbp)) > > (action, ucbp, (void *) &next_vrs); > > +#endif > > > > saved_vrs.prev_sp = VRS_SP (&next_vrs); > > } > > @@ -384,6 +437,11 @@ unwind_phase2_forced (_Unwind_Control_Block *ucbp, > phase2_vrs *entry_vrs, > > return _URC_FAILURE; > > } > > > > +#if __FDPIC__ > > + /* r9 could have been lost due to PLT jump. Restore correct value. > */ > > + saved_vrs.core.r[FDPIC_REGNUM] = gnu_Unwind_Find_got (VRS_PC > (&saved_vrs)); > > +#endif > > + > > uw_restore_core_regs (&saved_vrs, &saved_vrs.core); > > } > > > > @@ -429,8 +487,18 @@ __gnu_Unwind_RaiseException (_Unwind_Control_Block > * ucbp, > > return _URC_FAILURE; > > > > /* Call the pr to decide what to do. */ > > +#if __FDPIC__ > > + { > > + volatile struct funcdesc_t funcdesc; > > + funcdesc.ptr = UCB_PR_ADDR (ucbp); > > + funcdesc.got = UCB_PR_GOT (ucbp); > > + pr_result = ((personality_routine) &funcdesc) > > + (_US_VIRTUAL_UNWIND_FRAME, ucbp, (void *) &saved_vrs); > > + } > > +#else > > pr_result = ((personality_routine) UCB_PR_ADDR (ucbp)) > > (_US_VIRTUAL_UNWIND_FRAME, ucbp, (void *) &saved_vrs); > > +#endif > > } > > while (pr_result == _URC_CONTINUE_UNWIND); > > > > @@ -488,13 +556,27 @@ __gnu_Unwind_Resume (_Unwind_Control_Block * ucbp, > phase2_vrs * entry_vrs) > > } > > > > /* Call the cached PR. */ > > +#if __FDPIC__ > > + { > > + volatile struct funcdesc_t funcdesc; > > + funcdesc.ptr = UCB_PR_ADDR (ucbp); > > + funcdesc.got = UCB_PR_GOT (ucbp); > > + pr_result = ((personality_routine) &funcdesc) > > + (_US_UNWIND_FRAME_RESUME, ucbp, (_Unwind_Context *) entry_vrs); > > + } > > +#else > > pr_result = ((personality_routine) UCB_PR_ADDR (ucbp)) > > (_US_UNWIND_FRAME_RESUME, ucbp, (_Unwind_Context *) entry_vrs); > > +#endif > > > > switch (pr_result) > > { > > case _URC_INSTALL_CONTEXT: > > /* Upload the registers to enter the landing pad. */ > > +#if __FDPIC__ > > + /* r9 could have been lost due to PLT jump. Restore correct > value. */ > > + entry_vrs->core.r[FDPIC_REGNUM] = gnu_Unwind_Find_got (VRS_PC > (entry_vrs)); > > +#endif > > uw_restore_core_regs (entry_vrs, &entry_vrs->core); > > > > case _URC_CONTINUE_UNWIND: > > @@ -586,9 +668,20 @@ __gnu_Unwind_Backtrace(_Unwind_Trace_Fn trace, void > * trace_argument, > > } > > > > /* Call the pr to decide what to do. */ > > +#if __FDPIC__ > > + { > > + volatile struct funcdesc_t funcdesc; > > + funcdesc.ptr = UCB_PR_ADDR (ucbp); > > + funcdesc.got = UCB_PR_GOT (ucbp); > > + code = ((personality_routine) &funcdesc) > > + (_US_VIRTUAL_UNWIND_FRAME | _US_FORCE_UNWIND, > > + ucbp, (void *) &saved_vrs); > > + } > > +#else > > code = ((personality_routine) UCB_PR_ADDR (ucbp)) > > (_US_VIRTUAL_UNWIND_FRAME | _US_FORCE_UNWIND, > > ucbp, (void *) &saved_vrs); > > +#endif > > } > > while (code != _URC_END_OF_STACK > > && code != _URC_FAILURE); > > diff --git a/libgcc/unwind-pe.h b/libgcc/unwind-pe.h > > index dd5ae95..9c5177f 100644 > > --- a/libgcc/unwind-pe.h > > +++ b/libgcc/unwind-pe.h > > @@ -259,10 +259,27 @@ read_encoded_value_with_base (unsigned char > encoding, _Unwind_Ptr base, > > > > if (result != 0) > > { > > +#if __FDPIC__ > > + /* FDPIC relative addresses imply taking the GOT address > > + into account. */ > > + if ((encoding & DW_EH_PE_pcrel) && (encoding & > DW_EH_PE_indirect)) > > + { > > + result += gnu_Unwind_Find_got ((_Unwind_Ptr) u); > > + result = *(_Unwind_Internal_Ptr *) result; > > + } > > + else > > + { > > + result += ((encoding & 0x70) == DW_EH_PE_pcrel > > + ? (_Unwind_Internal_Ptr) u : base); > > + if (encoding & DW_EH_PE_indirect) > > + result = *(_Unwind_Internal_Ptr *) result; > > + } > > +#else > > result += ((encoding & 0x70) == DW_EH_PE_pcrel > > ? (_Unwind_Internal_Ptr) u : base); > > if (encoding & DW_EH_PE_indirect) > > result = *(_Unwind_Internal_Ptr *) result; > > +#endif > > } > > } > > > > diff --git a/libstdc++-v3/libsupc++/eh_personality.cc > b/libstdc++-v3/libsupc++/eh_personality.cc > > index 1b336c7..7b26b8d 100644 > > --- a/libstdc++-v3/libsupc++/eh_personality.cc > > +++ b/libstdc++-v3/libsupc++/eh_personality.cc > > @@ -93,7 +93,15 @@ get_ttype_entry (lsda_header_info *info, _uleb128_t i) > > _Unwind_Ptr ptr; > > > > i *= size_of_encoded_value (info->ttype_encoding); > > - read_encoded_value_with_base (info->ttype_encoding, info->ttype_base, > > + read_encoded_value_with_base ( > > +#if __FDPIC__ > > + /* Force these flags to nake sure to > > + take the GOT into account. */ > > + (DW_EH_PE_pcrel | DW_EH_PE_indirect), > > +#else > > + info->ttype_encoding, > > +#endif > > + info->ttype_base, > > info->TType - i, &ptr); > > > > return reinterpret_cast<const std::type_info *>(ptr); > > > > Nearly all of the above is outside of my comfort zone... I can't help > feeling that there ought to be a less invasive way to do this, but > without being particularly familiar with the code it's difficult to be > sure. > > The last two files patched will need approval from a relevant component > maintainer. >
diff --git a/gcc/ginclude/unwind-arm-common.h b/gcc/ginclude/unwind-arm-common.h index 8a1a919..f663891 100644 --- a/gcc/ginclude/unwind-arm-common.h +++ b/gcc/ginclude/unwind-arm-common.h @@ -91,7 +91,7 @@ extern "C" { _uw reserved2; /* Personality routine address */ _uw reserved3; /* Saved callsite address */ _uw reserved4; /* Forced unwind stop arg */ - _uw reserved5; + _uw reserved5; /* Personality routine GOT value in FDPIC mode. */ } unwinder_cache; /* Propagation barrier cache (valid after phase 1): */ @@ -247,4 +247,6 @@ typedef unsigned long _uleb128_t; } /* extern "C" */ #endif +#define FDPIC_REGNUM 9 + #endif /* defined UNWIND_ARM_COMMON_H */ diff --git a/libgcc/config/arm/linux-atomic.c b/libgcc/config/arm/linux-atomic.c index d334c58..161d1ce 100644 --- a/libgcc/config/arm/linux-atomic.c +++ b/libgcc/config/arm/linux-atomic.c @@ -25,11 +25,49 @@ see the files COPYING3 and COPYING.RUNTIME respectively. If not, see /* Kernel helper for compare-and-exchange. */ typedef int (__kernel_cmpxchg_t) (int oldval, int newval, int *ptr); +#if __FDPIC__ +/* Non-FDPIC ABIs call __kernel_cmpxchg directly by dereferencing its + address, but under FDPIC we would generate a broken call + sequence. That's why we have to implement __kernel_cmpxchg and + __kernel_dmb here: this way, the FDPIC call sequence works. */ +#define __kernel_cmpxchg __fdpic_cmpxchg +#else #define __kernel_cmpxchg (*(__kernel_cmpxchg_t *) 0xffff0fc0) +#endif /* Kernel helper for memory barrier. */ typedef void (__kernel_dmb_t) (void); +#if __FDPIC__ +#define __kernel_dmb __fdpic_dmb +#else #define __kernel_dmb (*(__kernel_dmb_t *) 0xffff0fa0) +#endif + +#if __FDPIC__ +static int __fdpic_cmpxchg (int oldval, int newval, int *ptr) +{ + int result; + + asm volatile ("1: ldrex r3, [%[ptr]]\n\t" + "subs r3, r3, %[oldval]\n\t" + "itt eq\n\t" + "strexeq r3, %[newval], [%[ptr]]\n\t" + "teqeq r3, #1\n\t" + "it eq\n\t" + "beq 1b\n\t" + "rsbs %[result], r3, #0\n\t" + : [result] "=r" (result) + : [oldval] "r" (oldval) , [newval] "r" (newval), [ptr] "r" (ptr) + : "r3"); + return result; +} + +static void __fdpic_dmb () +{ + asm volatile ("dmb\n\t"); +} + +#endif /* Note: we implement byte, short and int versions of atomic operations using the above kernel helpers; see linux-atomic-64bit.c for "long long" (64-bit) diff --git a/libgcc/config/arm/unwind-arm.h b/libgcc/config/arm/unwind-arm.h index 9f7d3f2..db5dfa2 100644 --- a/libgcc/config/arm/unwind-arm.h +++ b/libgcc/config/arm/unwind-arm.h @@ -33,9 +33,31 @@ /* Use IP as a scratch register within the personality routine. */ #define UNWIND_POINTER_REG 12 +#define STR(x) #x +#define XSTR(x) STR(x) + #ifdef __cplusplus extern "C" { #endif +_Unwind_Ptr __attribute__((weak)) __gnu_Unwind_Find_got (_Unwind_Ptr); + +static inline _Unwind_Ptr gnu_Unwind_Find_got (_Unwind_Ptr ptr) +{ + _Unwind_Ptr res; + + if (__gnu_Unwind_Find_got) + res = __gnu_Unwind_Find_got (ptr); + else + { + asm volatile ("mov %[result], r" XSTR(FDPIC_REGNUM) + : [result]"=r" (res) + : + :); + } + + return res; +} + /* Decode an R_ARM_TARGET2 relocation. */ static inline _Unwind_Word _Unwind_decode_typeinfo_ptr (_Unwind_Word base __attribute__ ((unused)), @@ -48,7 +70,12 @@ extern "C" { if (!tmp) return 0; -#if (defined(linux) && !defined(__uClinux__)) || defined(__NetBSD__) \ +#if __FDPIC__ + /* For FDPIC, we store the offset of the GOT entry. */ + /* So, first get GOT from dynamic linker and then use indirect access. */ + tmp += gnu_Unwind_Find_got (ptr); + tmp = *(_Unwind_Word *) tmp; +#elif (defined(linux) && !defined(__uClinux__)) || defined(__NetBSD__) \ || defined(__FreeBSD__) || defined(__fuchsia__) /* Pc-relative indirect. */ #define _GLIBCXX_OVERRIDE_TTYPE_ENCODING (DW_EH_PE_pcrel | DW_EH_PE_indirect) diff --git a/libgcc/unwind-arm-common.inc b/libgcc/unwind-arm-common.inc index 76f8fc3..7187edd 100644 --- a/libgcc/unwind-arm-common.inc +++ b/libgcc/unwind-arm-common.inc @@ -62,6 +62,7 @@ __gnu_Unwind_Find_exidx (_Unwind_Ptr, int *); #define UCB_PR_ADDR(ucbp) ((ucbp)->unwinder_cache.reserved2) #define UCB_SAVED_CALLSITE_ADDR(ucbp) ((ucbp)->unwinder_cache.reserved3) #define UCB_FORCED_STOP_ARG(ucbp) ((ucbp)->unwinder_cache.reserved4) +#define UCB_PR_GOT(ucbp) ((ucbp)->unwinder_cache.reserved5) /* Unwind descriptors. */ @@ -85,6 +86,15 @@ typedef struct __EIT_entry _uw content; } __EIT_entry; +#ifdef __FDPIC__ + +/* Only used in FDPIC case. */ +struct funcdesc_t { + unsigned int ptr; + unsigned int got; +}; +#endif + /* Assembly helper functions. */ /* Restore core register state. Never returns. */ @@ -259,7 +269,21 @@ get_eit_entry (_Unwind_Control_Block *ucbp, _uw return_address) { /* One of the predefined standard routines. */ _uw idx = (*(_uw *) ucbp->pr_cache.ehtp >> 24) & 0xf; +#if __FDPIC__ + { + struct funcdesc_t *funcdesc + = (struct funcdesc_t *) __gnu_unwind_get_pr_addr (idx); + if (funcdesc) + { + UCB_PR_ADDR (ucbp) = funcdesc->ptr; + UCB_PR_GOT (ucbp) = funcdesc->got; + } + else + UCB_PR_ADDR (ucbp) = 0; + } +#else UCB_PR_ADDR (ucbp) = __gnu_unwind_get_pr_addr (idx); +#endif if (UCB_PR_ADDR (ucbp) == 0) { /* Failed */ @@ -270,6 +294,10 @@ get_eit_entry (_Unwind_Control_Block *ucbp, _uw return_address) { /* Execute region offset to PR */ UCB_PR_ADDR (ucbp) = selfrel_offset31 (ucbp->pr_cache.ehtp); +#if __FDPIC__ + UCB_PR_GOT (ucbp) + = (unsigned int) gnu_Unwind_Find_got ((_Unwind_Ptr) UCB_PR_ADDR (ucbp)); +#endif } return _URC_OK; } @@ -291,14 +319,29 @@ unwind_phase2 (_Unwind_Control_Block * ucbp, phase2_vrs * vrs) UCB_SAVED_CALLSITE_ADDR (ucbp) = VRS_PC(vrs); /* Call the pr to decide what to do. */ +#if __FDPIC__ + { + volatile struct funcdesc_t funcdesc; + funcdesc.ptr = UCB_PR_ADDR (ucbp); + funcdesc.got = UCB_PR_GOT (ucbp); + pr_result = ((personality_routine) &funcdesc) + (_US_UNWIND_FRAME_STARTING, ucbp, (_Unwind_Context *) vrs); + } +#else pr_result = ((personality_routine) UCB_PR_ADDR (ucbp)) (_US_UNWIND_FRAME_STARTING, ucbp, (_Unwind_Context *) vrs); +#endif } while (pr_result == _URC_CONTINUE_UNWIND); if (pr_result != _URC_INSTALL_CONTEXT) abort(); +#if __FDPIC__ + /* r9 could have been lost due to PLT jump. Restore correct value. */ + vrs->core.r[FDPIC_REGNUM] = gnu_Unwind_Find_got (VRS_PC (vrs)); +#endif + uw_restore_core_regs (vrs, &vrs->core); } @@ -346,8 +389,18 @@ unwind_phase2_forced (_Unwind_Control_Block *ucbp, phase2_vrs *entry_vrs, next_vrs = saved_vrs; /* Call the pr to decide what to do. */ +#if __FDPIC__ + { + volatile struct funcdesc_t funcdesc; + funcdesc.ptr = UCB_PR_ADDR (ucbp); + funcdesc.got = UCB_PR_GOT (ucbp); + pr_result = ((personality_routine) &funcdesc) + (action, ucbp, (void *) &next_vrs); + } +#else pr_result = ((personality_routine) UCB_PR_ADDR (ucbp)) (action, ucbp, (void *) &next_vrs); +#endif saved_vrs.prev_sp = VRS_SP (&next_vrs); } @@ -384,6 +437,11 @@ unwind_phase2_forced (_Unwind_Control_Block *ucbp, phase2_vrs *entry_vrs, return _URC_FAILURE; } +#if __FDPIC__ + /* r9 could have been lost due to PLT jump. Restore correct value. */ + saved_vrs.core.r[FDPIC_REGNUM] = gnu_Unwind_Find_got (VRS_PC (&saved_vrs)); +#endif + uw_restore_core_regs (&saved_vrs, &saved_vrs.core); } @@ -429,8 +487,18 @@ __gnu_Unwind_RaiseException (_Unwind_Control_Block * ucbp, return _URC_FAILURE; /* Call the pr to decide what to do. */ +#if __FDPIC__ + { + volatile struct funcdesc_t funcdesc; + funcdesc.ptr = UCB_PR_ADDR (ucbp); + funcdesc.got = UCB_PR_GOT (ucbp); + pr_result = ((personality_routine) &funcdesc) + (_US_VIRTUAL_UNWIND_FRAME, ucbp, (void *) &saved_vrs); + } +#else pr_result = ((personality_routine) UCB_PR_ADDR (ucbp)) (_US_VIRTUAL_UNWIND_FRAME, ucbp, (void *) &saved_vrs); +#endif } while (pr_result == _URC_CONTINUE_UNWIND); @@ -488,13 +556,27 @@ __gnu_Unwind_Resume (_Unwind_Control_Block * ucbp, phase2_vrs * entry_vrs) } /* Call the cached PR. */ +#if __FDPIC__ + { + volatile struct funcdesc_t funcdesc; + funcdesc.ptr = UCB_PR_ADDR (ucbp); + funcdesc.got = UCB_PR_GOT (ucbp); + pr_result = ((personality_routine) &funcdesc) + (_US_UNWIND_FRAME_RESUME, ucbp, (_Unwind_Context *) entry_vrs); + } +#else pr_result = ((personality_routine) UCB_PR_ADDR (ucbp)) (_US_UNWIND_FRAME_RESUME, ucbp, (_Unwind_Context *) entry_vrs); +#endif switch (pr_result) { case _URC_INSTALL_CONTEXT: /* Upload the registers to enter the landing pad. */ +#if __FDPIC__ + /* r9 could have been lost due to PLT jump. Restore correct value. */ + entry_vrs->core.r[FDPIC_REGNUM] = gnu_Unwind_Find_got (VRS_PC (entry_vrs)); +#endif uw_restore_core_regs (entry_vrs, &entry_vrs->core); case _URC_CONTINUE_UNWIND: @@ -586,9 +668,20 @@ __gnu_Unwind_Backtrace(_Unwind_Trace_Fn trace, void * trace_argument, } /* Call the pr to decide what to do. */ +#if __FDPIC__ + { + volatile struct funcdesc_t funcdesc; + funcdesc.ptr = UCB_PR_ADDR (ucbp); + funcdesc.got = UCB_PR_GOT (ucbp); + code = ((personality_routine) &funcdesc) + (_US_VIRTUAL_UNWIND_FRAME | _US_FORCE_UNWIND, + ucbp, (void *) &saved_vrs); + } +#else code = ((personality_routine) UCB_PR_ADDR (ucbp)) (_US_VIRTUAL_UNWIND_FRAME | _US_FORCE_UNWIND, ucbp, (void *) &saved_vrs); +#endif } while (code != _URC_END_OF_STACK && code != _URC_FAILURE); diff --git a/libgcc/unwind-pe.h b/libgcc/unwind-pe.h index dd5ae95..9c5177f 100644 --- a/libgcc/unwind-pe.h +++ b/libgcc/unwind-pe.h @@ -259,10 +259,27 @@ read_encoded_value_with_base (unsigned char encoding, _Unwind_Ptr base, if (result != 0) { +#if __FDPIC__ + /* FDPIC relative addresses imply taking the GOT address + into account. */ + if ((encoding & DW_EH_PE_pcrel) && (encoding & DW_EH_PE_indirect)) + { + result += gnu_Unwind_Find_got ((_Unwind_Ptr) u); + result = *(_Unwind_Internal_Ptr *) result; + } + else + { + result += ((encoding & 0x70) == DW_EH_PE_pcrel + ? (_Unwind_Internal_Ptr) u : base); + if (encoding & DW_EH_PE_indirect) + result = *(_Unwind_Internal_Ptr *) result; + } +#else result += ((encoding & 0x70) == DW_EH_PE_pcrel ? (_Unwind_Internal_Ptr) u : base); if (encoding & DW_EH_PE_indirect) result = *(_Unwind_Internal_Ptr *) result; +#endif } } diff --git a/libstdc++-v3/libsupc++/eh_personality.cc b/libstdc++-v3/libsupc++/eh_personality.cc index 1b336c7..7b26b8d 100644 --- a/libstdc++-v3/libsupc++/eh_personality.cc +++ b/libstdc++-v3/libsupc++/eh_personality.cc @@ -93,7 +93,15 @@ get_ttype_entry (lsda_header_info *info, _uleb128_t i) _Unwind_Ptr ptr; i *= size_of_encoded_value (info->ttype_encoding); - read_encoded_value_with_base (info->ttype_encoding, info->ttype_base, + read_encoded_value_with_base ( +#if __FDPIC__ + /* Force these flags to nake sure to + take the GOT into account. */ + (DW_EH_PE_pcrel | DW_EH_PE_indirect), +#else + info->ttype_encoding, +#endif + info->ttype_base, info->TType - i, &ptr); return reinterpret_cast<const std::type_info *>(ptr);