296 lines
8.2 KiB
C
296 lines
8.2 KiB
C
/* Copyright (C) 2001, 2002 Free Software Foundation, Inc.
|
|
Contributed by Jakub Jelinek <jakub@redhat.com>.
|
|
|
|
This file is part of GNU CC.
|
|
|
|
GNU CC is free software; you can redistribute it and/or modify
|
|
it under the terms of the GNU General Public License as published by
|
|
the Free Software Foundation; either version 2, or (at your option)
|
|
any later version.
|
|
|
|
GNU CC is distributed in the hope that it will be useful,
|
|
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
GNU General Public License for more details.
|
|
|
|
You should have received a copy of the GNU General Public License
|
|
along with GNU CC; see the file COPYING. If not, write to
|
|
the Free Software Foundation, 59 Temple Place - Suite 330,
|
|
Boston, MA 02111-1307, USA. */
|
|
|
|
/* As a special exception, if you link this library with other files,
|
|
some of which are compiled with GCC, to produce an executable,
|
|
this library does not by itself cause the resulting executable
|
|
to be covered by the GNU General Public License.
|
|
This exception does not however invalidate any other reasons why
|
|
the executable file might be covered by the GNU General Public License. */
|
|
|
|
/* Locate the FDE entry for a given address, using PT_GNU_EH_FRAME ELF
|
|
segment and dl_iterate_phdr to avoid register/deregister calls at
|
|
DSO load/unload. */
|
|
|
|
#include "auto-host.h" /* For HAVE_LD_EH_FRAME_HDR. */
|
|
#include "tconfig.h"
|
|
#ifndef inhibit_libc
|
|
#include <stddef.h>
|
|
#include <stdlib.h>
|
|
#include <link.h>
|
|
#endif
|
|
#include "tsystem.h"
|
|
#include "dwarf2.h"
|
|
#include "unwind.h"
|
|
#define NO_BASE_OF_ENCODED_VALUE
|
|
#include "unwind-pe.h"
|
|
#include "unwind-dw2-fde.h"
|
|
#include "gthr.h"
|
|
|
|
#if !defined(inhibit_libc) && defined(HAVE_LD_EH_FRAME_HDR) \
|
|
&& (__GLIBC__ > 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ > 2) \
|
|
|| (__GLIBC__ == 2 && __GLIBC_MINOR__ == 2 && defined(DT_CONFIG)))
|
|
|
|
static fde * _Unwind_Find_registered_FDE (void *pc, struct dwarf_eh_bases *bases);
|
|
|
|
#define _Unwind_Find_FDE _Unwind_Find_registered_FDE
|
|
#include "unwind-dw2-fde.c"
|
|
#undef _Unwind_Find_FDE
|
|
|
|
#ifndef PT_GNU_EH_FRAME
|
|
#define PT_GNU_EH_FRAME (PT_LOOS + 0x474e550)
|
|
#endif
|
|
|
|
struct unw_eh_callback_data
|
|
{
|
|
_Unwind_Ptr pc;
|
|
void *tbase;
|
|
void *dbase;
|
|
void *func;
|
|
fde *ret;
|
|
};
|
|
|
|
struct unw_eh_frame_hdr
|
|
{
|
|
unsigned char version;
|
|
unsigned char eh_frame_ptr_enc;
|
|
unsigned char fde_count_enc;
|
|
unsigned char table_enc;
|
|
};
|
|
|
|
/* Like base_of_encoded_value, but take the base from a struct object
|
|
instead of an _Unwind_Context. */
|
|
|
|
static _Unwind_Ptr
|
|
base_from_cb_data (unsigned char encoding, struct unw_eh_callback_data *data)
|
|
{
|
|
if (encoding == DW_EH_PE_omit)
|
|
return 0;
|
|
|
|
switch (encoding & 0x70)
|
|
{
|
|
case DW_EH_PE_absptr:
|
|
case DW_EH_PE_pcrel:
|
|
case DW_EH_PE_aligned:
|
|
return 0;
|
|
|
|
case DW_EH_PE_textrel:
|
|
return (_Unwind_Ptr) data->tbase;
|
|
case DW_EH_PE_datarel:
|
|
return (_Unwind_Ptr) data->dbase;
|
|
}
|
|
abort ();
|
|
}
|
|
|
|
static int
|
|
_Unwind_IteratePhdrCallback (struct dl_phdr_info *info, size_t size, void *ptr)
|
|
{
|
|
struct unw_eh_callback_data *data = (struct unw_eh_callback_data *) ptr;
|
|
const ElfW(Phdr) *phdr, *p_eh_frame_hdr, *p_dynamic;
|
|
long n, match;
|
|
_Unwind_Ptr load_base;
|
|
const unsigned char *p;
|
|
const struct unw_eh_frame_hdr *hdr;
|
|
_Unwind_Ptr eh_frame;
|
|
struct object ob;
|
|
|
|
/* Make sure struct dl_phdr_info is at least as big as we need. */
|
|
if (size < offsetof (struct dl_phdr_info, dlpi_phnum)
|
|
+ sizeof (info->dlpi_phnum))
|
|
return -1;
|
|
|
|
match = 0;
|
|
phdr = info->dlpi_phdr;
|
|
load_base = info->dlpi_addr;
|
|
p_eh_frame_hdr = NULL;
|
|
p_dynamic = NULL;
|
|
|
|
/* See if PC falls into one of the loaded segments. Find the eh_frame
|
|
segment at the same time. */
|
|
for (n = info->dlpi_phnum; --n >= 0; phdr++)
|
|
{
|
|
if (phdr->p_type == PT_LOAD)
|
|
{
|
|
_Unwind_Ptr vaddr = phdr->p_vaddr + load_base;
|
|
if (data->pc >= vaddr && data->pc < vaddr + phdr->p_memsz)
|
|
match = 1;
|
|
}
|
|
else if (phdr->p_type == PT_GNU_EH_FRAME)
|
|
p_eh_frame_hdr = phdr;
|
|
else if (phdr->p_type == PT_DYNAMIC)
|
|
p_dynamic = phdr;
|
|
}
|
|
if (!match || !p_eh_frame_hdr)
|
|
return 0;
|
|
|
|
/* Read .eh_frame_hdr header. */
|
|
hdr = (const struct unw_eh_frame_hdr *)
|
|
(p_eh_frame_hdr->p_vaddr + load_base);
|
|
if (hdr->version != 1)
|
|
return 1;
|
|
|
|
#ifdef CRT_GET_RFIB_DATA
|
|
# ifdef __i386__
|
|
data->dbase = NULL;
|
|
if (p_dynamic)
|
|
{
|
|
/* For dynamicly linked executables and shared libraries,
|
|
DT_PLTGOT is the gp value for that object. */
|
|
ElfW(Dyn) *dyn = (ElfW(Dyn) *) (p_dynamic->p_vaddr + load_base);
|
|
for (; dyn->d_tag != DT_NULL ; dyn++)
|
|
if (dyn->d_tag == DT_PLTGOT)
|
|
{
|
|
/* On IA-32, _DYNAMIC is writable and GLIBC has relocated it. */
|
|
data->dbase = (void *) dyn->d_un.d_ptr;
|
|
break;
|
|
}
|
|
}
|
|
# else
|
|
# error What is DW_EH_PE_datarel base on this platform?
|
|
# endif
|
|
#endif
|
|
#ifdef CRT_GET_RFIB_TEXT
|
|
# error What is DW_EH_PE_textrel base on this platform?
|
|
#endif
|
|
|
|
p = read_encoded_value_with_base (hdr->eh_frame_ptr_enc,
|
|
base_from_cb_data (hdr->eh_frame_ptr_enc,
|
|
data),
|
|
(const unsigned char *) (hdr + 1),
|
|
&eh_frame);
|
|
|
|
/* We require here specific table encoding to speed things up.
|
|
Also, DW_EH_PE_datarel here means using PT_GNU_EH_FRAME start
|
|
as base, not the processor specific DW_EH_PE_datarel. */
|
|
if (hdr->fde_count_enc != DW_EH_PE_omit
|
|
&& hdr->table_enc == (DW_EH_PE_datarel | DW_EH_PE_sdata4))
|
|
{
|
|
_Unwind_Ptr fde_count;
|
|
|
|
p = read_encoded_value_with_base (hdr->fde_count_enc,
|
|
base_from_cb_data (hdr->fde_count_enc,
|
|
data),
|
|
p, &fde_count);
|
|
/* Shouldn't happen. */
|
|
if (fde_count == 0)
|
|
return 1;
|
|
if ((((_Unwind_Ptr) p) & 3) == 0)
|
|
{
|
|
struct fde_table {
|
|
signed initial_loc __attribute__ ((mode (SI)));
|
|
signed fde __attribute__ ((mode (SI)));
|
|
};
|
|
const struct fde_table *table = (const struct fde_table *) p;
|
|
size_t lo, hi, mid;
|
|
_Unwind_Ptr data_base = (_Unwind_Ptr) hdr;
|
|
fde *f;
|
|
unsigned int f_enc, f_enc_size;
|
|
_Unwind_Ptr range;
|
|
|
|
mid = fde_count - 1;
|
|
if (data->pc < table[0].initial_loc + data_base)
|
|
return 1;
|
|
else if (data->pc < table[mid].initial_loc + data_base)
|
|
{
|
|
lo = 0;
|
|
hi = mid;
|
|
|
|
while (lo < hi)
|
|
{
|
|
mid = (lo + hi) / 2;
|
|
if (data->pc < table[mid].initial_loc + data_base)
|
|
hi = mid;
|
|
else if (data->pc >= table[mid + 1].initial_loc + data_base)
|
|
lo = mid + 1;
|
|
else
|
|
break;
|
|
}
|
|
|
|
if (lo >= hi)
|
|
__gxx_abort ();
|
|
}
|
|
|
|
f = (fde *) (table[mid].fde + data_base);
|
|
f_enc = get_fde_encoding (f);
|
|
f_enc_size = size_of_encoded_value (f_enc);
|
|
read_encoded_value_with_base (f_enc & 0x0f, 0,
|
|
&f->pc_begin[f_enc_size], &range);
|
|
if (data->pc < table[mid].initial_loc + data_base + range)
|
|
data->ret = f;
|
|
data->func = (void *) (table[mid].initial_loc + data_base);
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
/* We have no sorted search table, so need to go the slow way.
|
|
As soon as GLIBC will provide API so to notify that a library has been
|
|
removed, we could cache this (and thus use search_object). */
|
|
ob.pc_begin = NULL;
|
|
ob.tbase = data->tbase;
|
|
ob.dbase = data->dbase;
|
|
ob.u.single = (fde *) eh_frame;
|
|
ob.s.i = 0;
|
|
ob.s.b.mixed_encoding = 1; /* Need to assume worst case. */
|
|
data->ret = linear_search_fdes (&ob, (fde *) eh_frame, (void *) data->pc);
|
|
if (data->ret != NULL)
|
|
{
|
|
unsigned int encoding = get_fde_encoding (data->ret);
|
|
read_encoded_value_with_base (encoding,
|
|
base_from_cb_data (encoding, data),
|
|
data->ret->pc_begin,
|
|
(_Unwind_Ptr *)&data->func);
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
fde *
|
|
_Unwind_Find_FDE (void *pc, struct dwarf_eh_bases *bases)
|
|
{
|
|
struct unw_eh_callback_data data;
|
|
fde *ret;
|
|
|
|
ret = _Unwind_Find_registered_FDE (pc, bases);
|
|
if (ret != NULL)
|
|
return ret;
|
|
|
|
data.pc = (_Unwind_Ptr) pc;
|
|
data.tbase = NULL;
|
|
data.dbase = NULL;
|
|
data.func = NULL;
|
|
data.ret = NULL;
|
|
|
|
if (dl_iterate_phdr (_Unwind_IteratePhdrCallback, &data) < 0)
|
|
return NULL;
|
|
|
|
if (data.ret)
|
|
{
|
|
bases->tbase = data.tbase;
|
|
bases->dbase = data.dbase;
|
|
bases->func = data.func;
|
|
}
|
|
return data.ret;
|
|
}
|
|
|
|
#else
|
|
/* Prevent multiple include of header files. */
|
|
#define _Unwind_Find_FDE _Unwind_Find_FDE
|
|
#include "unwind-dw2-fde.c"
|
|
#endif
|