@@ -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): */
@@ -25,11 +25,62 @@ 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);
-#define __kernel_cmpxchg (*(__kernel_cmpxchg_t *) 0xffff0fc0)
+
+#define STR(X) #X
+#define XSTR(X) STR(X)
+
+#define KERNEL_CMPXCHG 0xffff0fc0
+
+#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 *) KERNEL_CMPXCHG)
+#endif
/* Kernel helper for memory barrier. */
typedef void (__kernel_dmb_t) (void);
-#define __kernel_dmb (*(__kernel_dmb_t *) 0xffff0fa0)
+
+#define KERNEL_DMB 0xffff0fa0
+
+#if __FDPIC__
+#define __kernel_dmb __fdpic_dmb
+#else
+#define __kernel_dmb (*(__kernel_dmb_t *) KERNEL_DMB)
+#endif
+
+#if __FDPIC__
+static int __fdpic_cmpxchg (int oldval, int newval, int *ptr)
+{
+ int result;
+
+ asm volatile (
+ "ldr ip, 1f\n\t"
+ "bx ip\n\t"
+ "1:\n\t"
+ ".word " XSTR(KERNEL_CMPXCHG) "\n\t"
+ : "=r" (result)
+ : "r" (oldval) , "r" (newval), "r" (ptr)
+ : "r3", "memory");
+ /* The result is actually returned by the kernel helper, we need
+ this to avoid a warning. */
+ return result;
+}
+
+static void __fdpic_dmb (void)
+{
+ asm volatile (
+ "ldr ip, 1f\n\t"
+ "bx ip\n\t"
+ "1:\n\t"
+ ".word " XSTR(KERNEL_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)
@@ -33,9 +33,33 @@
/* Use IP as a scratch register within the personality routine. */
#define UNWIND_POINTER_REG 12
+#define FDPIC_REGNUM 9
+
+#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 +72,12 @@ 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)
@@ -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 +86,16 @@ 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 +270,21 @@ 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 +295,10 @@ 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 +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[FDPIC_REGNUM] = 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[FDPIC_REGNUM] = 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[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 +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);
@@ -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
}
}
@@ -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);