diff mbox series

[ARM/FDPIC,06/21,ARM] FDPIC: Add support for c++ exceptions

Message ID 20180525080354.13295-7-christophe.lyon@st.com
State New
Headers show
Series FDPIC ARM for ARM | expand

Commit Message

Christophe Lyon May 25, 2018, 8:03 a.m. UTC
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.

	libgcc/
	* config/arm/linux-atomic.c (__ARM_ARCH__): Define.
	(__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: Ic0841eb3d7bfb0b3f6d187cd52a660b8fd394d85

Comments

Kyrill Tkachov June 8, 2018, 10:15 a.m. UTC | #1
Hi Christophe,

On 25/05/18 09:03, Christophe Lyon wrote:
> 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.
>
>         libgcc/
>         * config/arm/linux-atomic.c (__ARM_ARCH__): Define.
>         (__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: Ic0841eb3d7bfb0b3f6d187cd52a660b8fd394d85
>
> diff --git a/gcc/ginclude/unwind-arm-common.h b/gcc/ginclude/unwind-arm-common.h
> index 8a1a919..150bd0f 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): */
> diff --git a/libgcc/config/arm/linux-atomic.c b/libgcc/config/arm/linux-atomic.c
> index d334c58..a20ad94 100644
> --- a/libgcc/config/arm/linux-atomic.c
> +++ b/libgcc/config/arm/linux-atomic.c
> @@ -23,13 +23,99 @@ a copy of the GCC Runtime Library Exception along with this program;
>  see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
>  <http://www.gnu.org/licenses/>. */
>
> +#if defined(__ARM_ARCH_2__)
> +# define __ARM_ARCH__ 2
> +#endif
> +
> +#if defined(__ARM_ARCH_3__)
> +# define __ARM_ARCH__ 3
> +#endif
> +
> +#if defined(__ARM_ARCH_3M__) || defined(__ARM_ARCH_4__) \
> +  || defined(__ARM_ARCH_4T__)
> +/* We use __ARM_ARCH__ set to 4 here, but in reality it's any processor with
> +   long multiply instructions.  That includes v3M.  */
> +# define __ARM_ARCH__ 4
> +#endif
> +

Support for __ARM_ARCH_2__, __ARM_ARCH_3__, __ARM_ARCH_3M__ has been removed in GCC 9
so this code is dead.

I notice that in the removal I've missed out an occurrence of these in config/arm/lib1funcs.S.
If you want to remove those occurrences as a separate patch that would be preapproved.

Thanks,
Kyrill

> +#if defined(__ARM_ARCH_5__) || defined(__ARM_ARCH_5T__) \
> +  || defined(__ARM_ARCH_5E__) || defined(__ARM_ARCH_5TE__) \
> +  || defined(__ARM_ARCH_5TEJ__)
> +# define __ARM_ARCH__ 5
> +#endif
> +
> +#if defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) \
> +  || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) \
> +  || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) \
> +  || defined(__ARM_ARCH_6M__)
> +# define __ARM_ARCH__ 6
> +#endif
> +
> +#if defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) \
> +  || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) \
> +  || defined(__ARM_ARCH_7EM__)
> +# define __ARM_ARCH__ 7
> +#endif
> +
> +#ifndef __ARM_ARCH__
> +#error Unable to determine architecture.
> +#endif
> +
>  /* Kernel helper for compare-and-exchange.  */
>  typedef int (__kernel_cmpxchg_t) (int oldval, int newval, int *ptr);
> +#if __FDPIC__
> +#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)
> +{
> +#if __ARM_ARCH__ < 6
> +  #error architecture support not yet implemented
> +  /* Use swap instruction (but is it always safe ? (interrupt?))  */
> +#else
> +  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;
> +#endif
> +}
> +
> +static void __fdpic_dmb ()
> +{
> +#if __ARM_ARCH__ < 6
> +  /* No op? Perhaps flush write buffer ?  */
> +  return ;
> +#else
> + #if __ARM_ARCH__ >= 7
> +  asm volatile ("dmb\n\t");
> + #elif __ARM_ARCH__ == 6
> +  asm volatile ("mcr p15, 0, r0, c7, c10, 5\n\t");
> + #endif
> +#endif
> +}
> +
> +#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..a9598eb 100644
> --- a/libgcc/config/arm/unwind-arm.h
> +++ b/libgcc/config/arm/unwind-arm.h
> @@ -36,6 +36,25 @@
>  #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], r9"
> +                     : [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 +67,12 @@ 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..f5415c1 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 +86,12 @@ typedef struct __EIT_entry
>    _uw content;
>  } __EIT_entry;
>
> +/* Only used in FDPIC case.  */
> +struct funcdesc_t {
> +    unsigned int ptr;
> +    unsigned int got;
> +};
> +
>  /* Assembly helper functions.  */
>
>  /* Restore core register state.  Never returns.  */
> @@ -259,7 +266,23 @@ 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 */
> @@ -269,7 +292,13 @@ get_eit_entry (_Unwind_Control_Block *ucbp, _uw return_address)
>    else
>      {
>        /* Execute region offset to PR */
> +#if __FDPIC__
>        UCB_PR_ADDR (ucbp) = selfrel_offset31 (ucbp->pr_cache.ehtp);
> +      UCB_PR_GOT (ucbp)
> +       = (unsigned int) gnu_Unwind_Find_got ((_Unwind_Ptr) UCB_PR_ADDR (ucbp));
> +#else
> +      UCB_PR_ADDR (ucbp) = selfrel_offset31 (ucbp->pr_cache.ehtp);
> +#endif
>      }
>    return _URC_OK;
>  }
> @@ -291,14 +320,29 @@ 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[9] = gnu_Unwind_Find_got (VRS_PC (vrs));
> +#endif
> +
>    uw_restore_core_regs (vrs, &vrs->core);
>  }
>
> @@ -346,8 +390,18 @@ 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 +438,11 @@ 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[9] = gnu_Unwind_Find_got (VRS_PC (&saved_vrs));
> +#endif
> +
>    uw_restore_core_regs (&saved_vrs, &saved_vrs.core);
>  }
>
> @@ -429,8 +488,18 @@ __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 +557,27 @@ __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[9] = gnu_Unwind_Find_got (VRS_PC (entry_vrs));
> +#endif
>        uw_restore_core_regs (entry_vrs, &entry_vrs->core);
>
>      case _URC_CONTINUE_UNWIND:
> @@ -586,9 +669,20 @@ __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..c18dffe 100644
> --- a/libgcc/unwind-pe.h
> +++ b/libgcc/unwind-pe.h
> @@ -259,10 +259,25 @@ read_encoded_value_with_base (unsigned char encoding, _Unwind_Ptr base,
>
>        if (result != 0)
>          {
> +#if __FDPIC__
> +    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..138b606 100644
> --- a/libstdc++-v3/libsupc++/eh_personality.cc
> +++ b/libstdc++-v3/libsupc++/eh_personality.cc
> @@ -93,7 +93,13 @@ 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__
> +               (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);
> -- 
> 2.6.3
>
Richard Earnshaw (lists) June 8, 2018, 10:51 a.m. UTC | #2
On 08/06/18 11:15, Kyrill Tkachov wrote:
> Hi Christophe,
> 
> On 25/05/18 09:03, Christophe Lyon wrote:
>> 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.
>>
>>         libgcc/
>>         * config/arm/linux-atomic.c (__ARM_ARCH__): Define.
>>         (__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: Ic0841eb3d7bfb0b3f6d187cd52a660b8fd394d85
>>
>> diff --git a/gcc/ginclude/unwind-arm-common.h
>> b/gcc/ginclude/unwind-arm-common.h
>> index 8a1a919..150bd0f 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): */
>> diff --git a/libgcc/config/arm/linux-atomic.c
>> b/libgcc/config/arm/linux-atomic.c
>> index d334c58..a20ad94 100644
>> --- a/libgcc/config/arm/linux-atomic.c
>> +++ b/libgcc/config/arm/linux-atomic.c
>> @@ -23,13 +23,99 @@ a copy of the GCC Runtime Library Exception along
>> with this program;
>>  see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
>>  <http://www.gnu.org/licenses/>. */
>>
>> +#if defined(__ARM_ARCH_2__)
>> +# define __ARM_ARCH__ 2
>> +#endif
>> +
>> +#if defined(__ARM_ARCH_3__)
>> +# define __ARM_ARCH__ 3
>> +#endif
>> +
>> +#if defined(__ARM_ARCH_3M__) || defined(__ARM_ARCH_4__) \
>> +  || defined(__ARM_ARCH_4T__)
>> +/* We use __ARM_ARCH__ set to 4 here, but in reality it's any
>> processor with
>> +   long multiply instructions.  That includes v3M.  */
>> +# define __ARM_ARCH__ 4
>> +#endif
>> +
> 
> Support for __ARM_ARCH_2__, __ARM_ARCH_3__, __ARM_ARCH_3M__ has been
> removed in GCC 9
> so this code is dead.

Better still, use the ACLE pre-defines rather than the awkward GCC
versions which need updating each time a new architecture variant is added.

R.

> 
> I notice that in the removal I've missed out an occurrence of these in
> config/arm/lib1funcs.S.
> If you want to remove those occurrences as a separate patch that would
> be preapproved.
> 
> Thanks,
> Kyrill
> 
>> +#if defined(__ARM_ARCH_5__) || defined(__ARM_ARCH_5T__) \
>> +  || defined(__ARM_ARCH_5E__) || defined(__ARM_ARCH_5TE__) \
>> +  || defined(__ARM_ARCH_5TEJ__)
>> +# define __ARM_ARCH__ 5
>> +#endif
>> +
>> +#if defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) \
>> +  || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) \
>> +  || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) \
>> +  || defined(__ARM_ARCH_6M__)
>> +# define __ARM_ARCH__ 6
>> +#endif
>> +
>> +#if defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) \
>> +  || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) \
>> +  || defined(__ARM_ARCH_7EM__)
>> +# define __ARM_ARCH__ 7
>> +#endif
>> +
>> +#ifndef __ARM_ARCH__
>> +#error Unable to determine architecture.
>> +#endif
>> +
>>  /* Kernel helper for compare-and-exchange.  */
>>  typedef int (__kernel_cmpxchg_t) (int oldval, int newval, int *ptr);
>> +#if __FDPIC__
>> +#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)
>> +{
>> +#if __ARM_ARCH__ < 6
>> +  #error architecture support not yet implemented
>> +  /* Use swap instruction (but is it always safe ? (interrupt?))  */
>> +#else
>> +  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;
>> +#endif
>> +}
>> +
>> +static void __fdpic_dmb ()
>> +{
>> +#if __ARM_ARCH__ < 6
>> +  /* No op? Perhaps flush write buffer ?  */
>> +  return ;
>> +#else
>> + #if __ARM_ARCH__ >= 7
>> +  asm volatile ("dmb\n\t");
>> + #elif __ARM_ARCH__ == 6
>> +  asm volatile ("mcr p15, 0, r0, c7, c10, 5\n\t");
>> + #endif
>> +#endif
>> +}
>> +
>> +#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..a9598eb 100644
>> --- a/libgcc/config/arm/unwind-arm.h
>> +++ b/libgcc/config/arm/unwind-arm.h
>> @@ -36,6 +36,25 @@
>>  #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], r9"
>> +                     : [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 +67,12 @@ 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..f5415c1 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 +86,12 @@ typedef struct __EIT_entry
>>    _uw content;
>>  } __EIT_entry;
>>
>> +/* Only used in FDPIC case.  */
>> +struct funcdesc_t {
>> +    unsigned int ptr;
>> +    unsigned int got;
>> +};
>> +
>>  /* Assembly helper functions.  */
>>
>>  /* Restore core register state.  Never returns.  */
>> @@ -259,7 +266,23 @@ 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 */
>> @@ -269,7 +292,13 @@ get_eit_entry (_Unwind_Control_Block *ucbp, _uw
>> return_address)
>>    else
>>      {
>>        /* Execute region offset to PR */
>> +#if __FDPIC__
>>        UCB_PR_ADDR (ucbp) = selfrel_offset31 (ucbp->pr_cache.ehtp);
>> +      UCB_PR_GOT (ucbp)
>> +       = (unsigned int) gnu_Unwind_Find_got ((_Unwind_Ptr)
>> UCB_PR_ADDR (ucbp));
>> +#else
>> +      UCB_PR_ADDR (ucbp) = selfrel_offset31 (ucbp->pr_cache.ehtp);
>> +#endif
>>      }
>>    return _URC_OK;
>>  }
>> @@ -291,14 +320,29 @@ 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[9] = gnu_Unwind_Find_got (VRS_PC (vrs));
>> +#endif
>> +
>>    uw_restore_core_regs (vrs, &vrs->core);
>>  }
>>
>> @@ -346,8 +390,18 @@ 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 +438,11 @@ 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[9] = gnu_Unwind_Find_got (VRS_PC (&saved_vrs));
>> +#endif
>> +
>>    uw_restore_core_regs (&saved_vrs, &saved_vrs.core);
>>  }
>>
>> @@ -429,8 +488,18 @@ __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 +557,27 @@ __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[9] = gnu_Unwind_Find_got (VRS_PC (entry_vrs));
>> +#endif
>>        uw_restore_core_regs (entry_vrs, &entry_vrs->core);
>>
>>      case _URC_CONTINUE_UNWIND:
>> @@ -586,9 +669,20 @@ __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..c18dffe 100644
>> --- a/libgcc/unwind-pe.h
>> +++ b/libgcc/unwind-pe.h
>> @@ -259,10 +259,25 @@ read_encoded_value_with_base (unsigned char
>> encoding, _Unwind_Ptr base,
>>
>>        if (result != 0)
>>          {
>> +#if __FDPIC__
>> +    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..138b606 100644
>> --- a/libstdc++-v3/libsupc++/eh_personality.cc
>> +++ b/libstdc++-v3/libsupc++/eh_personality.cc
>> @@ -93,7 +93,13 @@ 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__
>> +               (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);
>> -- 
>> 2.6.3
>>
>
Christophe Lyon June 11, 2018, 6:49 a.m. UTC | #3
On 8 June 2018 at 12:51, Richard Earnshaw (lists)
<Richard.Earnshaw@arm.com> wrote:
> On 08/06/18 11:15, Kyrill Tkachov wrote:
>> Hi Christophe,
>>
>> On 25/05/18 09:03, Christophe Lyon wrote:
>>> 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.
>>>
>>>         libgcc/
>>>         * config/arm/linux-atomic.c (__ARM_ARCH__): Define.
>>>         (__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: Ic0841eb3d7bfb0b3f6d187cd52a660b8fd394d85
>>>
>>> diff --git a/gcc/ginclude/unwind-arm-common.h
>>> b/gcc/ginclude/unwind-arm-common.h
>>> index 8a1a919..150bd0f 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): */
>>> diff --git a/libgcc/config/arm/linux-atomic.c
>>> b/libgcc/config/arm/linux-atomic.c
>>> index d334c58..a20ad94 100644
>>> --- a/libgcc/config/arm/linux-atomic.c
>>> +++ b/libgcc/config/arm/linux-atomic.c
>>> @@ -23,13 +23,99 @@ a copy of the GCC Runtime Library Exception along
>>> with this program;
>>>  see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
>>>  <http://www.gnu.org/licenses/>. */
>>>
>>> +#if defined(__ARM_ARCH_2__)
>>> +# define __ARM_ARCH__ 2
>>> +#endif
>>> +
>>> +#if defined(__ARM_ARCH_3__)
>>> +# define __ARM_ARCH__ 3
>>> +#endif
>>> +
>>> +#if defined(__ARM_ARCH_3M__) || defined(__ARM_ARCH_4__) \
>>> +  || defined(__ARM_ARCH_4T__)
>>> +/* We use __ARM_ARCH__ set to 4 here, but in reality it's any
>>> processor with
>>> +   long multiply instructions.  That includes v3M.  */
>>> +# define __ARM_ARCH__ 4
>>> +#endif
>>> +
>>
>> Support for __ARM_ARCH_2__, __ARM_ARCH_3__, __ARM_ARCH_3M__ has been
>> removed in GCC 9
>> so this code is dead.
>
> Better still, use the ACLE pre-defines rather than the awkward GCC
> versions which need updating each time a new architecture variant is added.
>

Indeed, that's a better solution. I did notice discrepancies between
several copies of this code block in various GCC libs.


> R.
>
>>
>> I notice that in the removal I've missed out an occurrence of these in
>> config/arm/lib1funcs.S.
>> If you want to remove those occurrences as a separate patch that would
>> be preapproved.
>>
>> Thanks,
>> Kyrill
>>
>>> +#if defined(__ARM_ARCH_5__) || defined(__ARM_ARCH_5T__) \
>>> +  || defined(__ARM_ARCH_5E__) || defined(__ARM_ARCH_5TE__) \
>>> +  || defined(__ARM_ARCH_5TEJ__)
>>> +# define __ARM_ARCH__ 5
>>> +#endif
>>> +
>>> +#if defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) \
>>> +  || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) \
>>> +  || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) \
>>> +  || defined(__ARM_ARCH_6M__)
>>> +# define __ARM_ARCH__ 6
>>> +#endif
>>> +
>>> +#if defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) \
>>> +  || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) \
>>> +  || defined(__ARM_ARCH_7EM__)
>>> +# define __ARM_ARCH__ 7
>>> +#endif
>>> +
>>> +#ifndef __ARM_ARCH__
>>> +#error Unable to determine architecture.
>>> +#endif
>>> +
>>>  /* Kernel helper for compare-and-exchange.  */
>>>  typedef int (__kernel_cmpxchg_t) (int oldval, int newval, int *ptr);
>>> +#if __FDPIC__
>>> +#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)
>>> +{
>>> +#if __ARM_ARCH__ < 6
>>> +  #error architecture support not yet implemented
>>> +  /* Use swap instruction (but is it always safe ? (interrupt?))  */
>>> +#else
>>> +  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;
>>> +#endif
>>> +}
>>> +
>>> +static void __fdpic_dmb ()
>>> +{
>>> +#if __ARM_ARCH__ < 6
>>> +  /* No op? Perhaps flush write buffer ?  */
>>> +  return ;
>>> +#else
>>> + #if __ARM_ARCH__ >= 7
>>> +  asm volatile ("dmb\n\t");
>>> + #elif __ARM_ARCH__ == 6
>>> +  asm volatile ("mcr p15, 0, r0, c7, c10, 5\n\t");
>>> + #endif
>>> +#endif
>>> +}
>>> +
>>> +#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..a9598eb 100644
>>> --- a/libgcc/config/arm/unwind-arm.h
>>> +++ b/libgcc/config/arm/unwind-arm.h
>>> @@ -36,6 +36,25 @@
>>>  #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], r9"
>>> +                     : [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 +67,12 @@ 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..f5415c1 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 +86,12 @@ typedef struct __EIT_entry
>>>    _uw content;
>>>  } __EIT_entry;
>>>
>>> +/* Only used in FDPIC case.  */
>>> +struct funcdesc_t {
>>> +    unsigned int ptr;
>>> +    unsigned int got;
>>> +};
>>> +
>>>  /* Assembly helper functions.  */
>>>
>>>  /* Restore core register state.  Never returns.  */
>>> @@ -259,7 +266,23 @@ 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 */
>>> @@ -269,7 +292,13 @@ get_eit_entry (_Unwind_Control_Block *ucbp, _uw
>>> return_address)
>>>    else
>>>      {
>>>        /* Execute region offset to PR */
>>> +#if __FDPIC__
>>>        UCB_PR_ADDR (ucbp) = selfrel_offset31 (ucbp->pr_cache.ehtp);
>>> +      UCB_PR_GOT (ucbp)
>>> +       = (unsigned int) gnu_Unwind_Find_got ((_Unwind_Ptr)
>>> UCB_PR_ADDR (ucbp));
>>> +#else
>>> +      UCB_PR_ADDR (ucbp) = selfrel_offset31 (ucbp->pr_cache.ehtp);
>>> +#endif
>>>      }
>>>    return _URC_OK;
>>>  }
>>> @@ -291,14 +320,29 @@ 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[9] = gnu_Unwind_Find_got (VRS_PC (vrs));
>>> +#endif
>>> +
>>>    uw_restore_core_regs (vrs, &vrs->core);
>>>  }
>>>
>>> @@ -346,8 +390,18 @@ 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 +438,11 @@ 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[9] = gnu_Unwind_Find_got (VRS_PC (&saved_vrs));
>>> +#endif
>>> +
>>>    uw_restore_core_regs (&saved_vrs, &saved_vrs.core);
>>>  }
>>>
>>> @@ -429,8 +488,18 @@ __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 +557,27 @@ __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[9] = gnu_Unwind_Find_got (VRS_PC (entry_vrs));
>>> +#endif
>>>        uw_restore_core_regs (entry_vrs, &entry_vrs->core);
>>>
>>>      case _URC_CONTINUE_UNWIND:
>>> @@ -586,9 +669,20 @@ __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..c18dffe 100644
>>> --- a/libgcc/unwind-pe.h
>>> +++ b/libgcc/unwind-pe.h
>>> @@ -259,10 +259,25 @@ read_encoded_value_with_base (unsigned char
>>> encoding, _Unwind_Ptr base,
>>>
>>>        if (result != 0)
>>>          {
>>> +#if __FDPIC__
>>> +    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..138b606 100644
>>> --- a/libstdc++-v3/libsupc++/eh_personality.cc
>>> +++ b/libstdc++-v3/libsupc++/eh_personality.cc
>>> @@ -93,7 +93,13 @@ 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__
>>> +               (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);
>>> --
>>> 2.6.3
>>>
>>
>
diff mbox series

Patch

diff --git a/gcc/ginclude/unwind-arm-common.h b/gcc/ginclude/unwind-arm-common.h
index 8a1a919..150bd0f 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): */
diff --git a/libgcc/config/arm/linux-atomic.c b/libgcc/config/arm/linux-atomic.c
index d334c58..a20ad94 100644
--- a/libgcc/config/arm/linux-atomic.c
+++ b/libgcc/config/arm/linux-atomic.c
@@ -23,13 +23,99 @@  a copy of the GCC Runtime Library Exception along with this program;
 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 <http://www.gnu.org/licenses/>.  */
 
+#if defined(__ARM_ARCH_2__)
+# define __ARM_ARCH__ 2
+#endif
+
+#if defined(__ARM_ARCH_3__)
+# define __ARM_ARCH__ 3
+#endif
+
+#if defined(__ARM_ARCH_3M__) || defined(__ARM_ARCH_4__) \
+  || defined(__ARM_ARCH_4T__)
+/* We use __ARM_ARCH__ set to 4 here, but in reality it's any processor with
+   long multiply instructions.  That includes v3M.  */
+# define __ARM_ARCH__ 4
+#endif
+
+#if defined(__ARM_ARCH_5__) || defined(__ARM_ARCH_5T__) \
+  || defined(__ARM_ARCH_5E__) || defined(__ARM_ARCH_5TE__) \
+  || defined(__ARM_ARCH_5TEJ__)
+# define __ARM_ARCH__ 5
+#endif
+
+#if defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) \
+  || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) \
+  || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__) \
+  || defined(__ARM_ARCH_6M__)
+# define __ARM_ARCH__ 6
+#endif
+
+#if defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) \
+  || defined(__ARM_ARCH_7R__) || defined(__ARM_ARCH_7M__) \
+  || defined(__ARM_ARCH_7EM__)
+# define __ARM_ARCH__ 7
+#endif
+
+#ifndef __ARM_ARCH__
+#error Unable to determine architecture.
+#endif
+
 /* Kernel helper for compare-and-exchange.  */
 typedef int (__kernel_cmpxchg_t) (int oldval, int newval, int *ptr);
+#if __FDPIC__
+#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)
+{
+#if __ARM_ARCH__ < 6
+  #error architecture support not yet implemented
+  /* Use swap instruction (but is it always safe ? (interrupt?))  */
+#else
+  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;
+#endif
+}
+
+static void __fdpic_dmb ()
+{
+#if __ARM_ARCH__ < 6
+  /* No op? Perhaps flush write buffer ?  */
+  return ;
+#else
+ #if __ARM_ARCH__ >= 7
+  asm volatile ("dmb\n\t");
+ #elif __ARM_ARCH__ == 6
+  asm volatile ("mcr p15, 0, r0, c7, c10, 5\n\t");
+ #endif
+#endif
+}
+
+#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..a9598eb 100644
--- a/libgcc/config/arm/unwind-arm.h
+++ b/libgcc/config/arm/unwind-arm.h
@@ -36,6 +36,25 @@ 
 #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], r9"
+		      : [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 +67,12 @@  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..f5415c1 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 +86,12 @@  typedef struct __EIT_entry
   _uw content;
 } __EIT_entry;
 
+/* Only used in FDPIC case.  */
+struct funcdesc_t {
+    unsigned int ptr;
+    unsigned int got;
+};
+
 /* Assembly helper functions.  */
 
 /* Restore core register state.  Never returns.  */
@@ -259,7 +266,23 @@  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 */
@@ -269,7 +292,13 @@  get_eit_entry (_Unwind_Control_Block *ucbp, _uw return_address)
   else
     {
       /* Execute region offset to PR */
+#if __FDPIC__
       UCB_PR_ADDR (ucbp) = selfrel_offset31 (ucbp->pr_cache.ehtp);
+      UCB_PR_GOT (ucbp)
+	= (unsigned int) gnu_Unwind_Find_got ((_Unwind_Ptr) UCB_PR_ADDR (ucbp));
+#else
+      UCB_PR_ADDR (ucbp) = selfrel_offset31 (ucbp->pr_cache.ehtp);
+#endif
     }
   return _URC_OK;
 }
@@ -291,14 +320,29 @@  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[9] = gnu_Unwind_Find_got (VRS_PC (vrs));
+#endif
+
   uw_restore_core_regs (vrs, &vrs->core);
 }
 
@@ -346,8 +390,18 @@  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 +438,11 @@  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[9] = gnu_Unwind_Find_got (VRS_PC (&saved_vrs));
+#endif
+
   uw_restore_core_regs (&saved_vrs, &saved_vrs.core);
 }
 
@@ -429,8 +488,18 @@  __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 +557,27 @@  __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[9] = gnu_Unwind_Find_got (VRS_PC (entry_vrs));
+#endif
       uw_restore_core_regs (entry_vrs, &entry_vrs->core);
 
     case _URC_CONTINUE_UNWIND:
@@ -586,9 +669,20 @@  __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..c18dffe 100644
--- a/libgcc/unwind-pe.h
+++ b/libgcc/unwind-pe.h
@@ -259,10 +259,25 @@  read_encoded_value_with_base (unsigned char encoding, _Unwind_Ptr base,
 
       if (result != 0)
 	{
+#if __FDPIC__
+    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..138b606 100644
--- a/libstdc++-v3/libsupc++/eh_personality.cc
+++ b/libstdc++-v3/libsupc++/eh_personality.cc
@@ -93,7 +93,13 @@  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__
+		(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);