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Also enable DWARF code for UNW_TARGET_HPPA.

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2004/11/23 16:59:56-08:00 mostang.com!davidm
(_UPTi_find_unwind_table): Implement first draft for x86/-64.

(Logical change 1.290)
This commit is contained in:
mostang.com!davidm 2005-05-03 09:13:17 +00:00
parent b267dfc8c9
commit 10a269d6d0
1 changed files with 158 additions and 14 deletions
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172
src/ptrace/_UPT_find_proc_info.c
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@ -145,27 +145,169 @@ _UPTi_find_unwind_table (struct UPT_info *ui, unw_addr_space_t as,
return &ui->di_cache;
}
#elif UNW_TARGET_X86
#elif UNW_TARGET_X86 || UNW_TARGET_X86_64 || UNW_TARGET_HPPA
#include "dwarf-eh.h"
#include "dwarf_i.h"
/* We need our own instance of dwarf_read_encoded_pointer() here since
the one in dwarf/Gpe.c is not (and should not be) exported. */
int
dwarf_read_encoded_pointer (unw_addr_space_t as, unw_accessors_t *a,
unw_word_t *addr, unsigned char encoding,
const unw_proc_info_t *pi,
unw_word_t *valp, void *arg)
{
return dwarf_read_encoded_pointer_inlined (as, a, addr, encoding,
pi, valp, arg);
}
HIDDEN unw_dyn_info_t *
_UPTi_find_unwind_table (struct UPT_info *ui, unw_addr_space_t as,
char *path, unw_word_t segbase, unw_word_t mapoff)
{
/* fix me */
return NULL;
Elf_W(Phdr) *phdr, *ptxt = NULL, *peh_hdr = NULL, *pdyn = NULL;
unw_word_t addr, eh_frame_start, fde_count, load_base;
struct dwarf_eh_frame_hdr *hdr;
unw_proc_info_t pi;
unw_accessors_t *a;
Elf_W(Ehdr) *ehdr;
int i, ret;
/* XXX: Much of this code is Linux/LSB-specific. */
if (!elf_w(valid_object) (&ui->ei))
return NULL;
ehdr = ui->ei.image;
phdr = (Elf_W(Phdr) *) ((char *) ui->ei.image + ehdr->e_phoff);
for (i = 0; i < ehdr->e_phnum; ++i)
{
switch (phdr[i].p_type)
{
case PT_LOAD:
if (phdr[i].p_offset == mapoff)
ptxt = phdr + i;
break;
case PT_GNU_EH_FRAME:
peh_hdr = phdr + i;
break;
case PT_DYNAMIC:
pdyn = phdr + i;
break;
default:
break;
}
}
if (!ptxt || !peh_hdr)
return NULL;
if (pdyn)
{
/* For dynamicly linked executables and shared libraries,
DT_PLTGOT is the value that data-relative addresses are
relative to for that object. We call this the "gp". */
Elf_W(Dyn) *dyn = (Elf_W(Dyn) *)(pdyn->p_offset
+ (char *) ui->ei.image);
for (; dyn->d_tag != DT_NULL; ++dyn)
if (dyn->d_tag == DT_PLTGOT)
{
/* Assume that _DYNAMIC is writable and GLIBC has
relocated it (true for x86 at least). */
ui->di_cache.gp = dyn->d_un.d_ptr;
break;
}
}
else
/* Otherwise this is a static executable with no _DYNAMIC. Assume
that data-relative addresses are relative to 0, i.e.,
absolute. */
ui->di_cache.gp = 0;
hdr = (struct dwarf_eh_frame_hdr *) (peh_hdr->p_offset
+ (char *) ui->ei.image);
if (hdr->version != DW_EH_VERSION)
{
Debug (1, "table `%s' has unexpected version %d\n",
path, hdr->version);
return 0;
}
a = unw_get_accessors (unw_local_addr_space);
addr = (unw_word_t) (hdr + 1);
/* Fill in a dummy proc_info structure. We just need to fill in
enough to ensure that dwarf_read_encoded_pointer() can do it's
job. Since we don't have a procedure-context at this point, all
we have to do is fill in the global-pointer. */
memset (&pi, 0, sizeof (pi));
pi.gp = ui->di_cache.gp;
/* (Optionally) read eh_frame_ptr: */
if ((ret = dwarf_read_encoded_pointer (unw_local_addr_space, a,
&addr, hdr->eh_frame_ptr_enc, &pi,
&eh_frame_start, NULL)) < 0)
return NULL;
/* (Optionally) read fde_count: */
if ((ret = dwarf_read_encoded_pointer (unw_local_addr_space, a,
&addr, hdr->fde_count_enc, &pi,
&fde_count, NULL)) < 0)
return NULL;
if (hdr->table_enc != (DW_EH_PE_datarel | DW_EH_PE_sdata4))
{
abort ();
#if 0
/* If there is no search table or it has an unsupported
encoding, fall back on linear search. */
if (hdr->table_enc == DW_EH_PE_omit)
Debug (4, "table `%s' lacks search table; doing linear search\n",
info->dlpi_name);
else
Debug (4, "table `%s' has encoding 0x%x; doing linear search\n",
info->dlpi_name, hdr->table_enc);
eh_frame_end = max_load_addr; /* XXX can we do better? */
if (hdr->fde_count_enc == DW_EH_PE_omit)
fde_count = ~0UL;
if (hdr->eh_frame_ptr_enc == DW_EH_PE_omit)
abort ();
cb_data->single_fde = 1;
return linear_search (unw_local_addr_space, ip,
eh_frame_start, eh_frame_end, fde_count,
pi, need_unwind_info, NULL);
#endif
}
load_base = segbase - ptxt->p_vaddr;
ui->di_cache.start_ip = segbase;
ui->di_cache.end_ip = ui->di_cache.start_ip + ptxt->p_memsz;
ui->di_cache.format = UNW_INFO_FORMAT_REMOTE_TABLE;
ui->di_cache.u.rti.name_ptr = 0;
/* two 32-bit values (ip_offset/fde_offset) per table-entry: */
ui->di_cache.u.rti.table_len = (fde_count * 8) / sizeof (unw_word_t);
ui->di_cache.u.rti.table_data = ((load_base + peh_hdr->p_vaddr)
+ (addr - (unw_word_t) ui->ei.image
- peh_hdr->p_offset));
/* For the binary-search table in the eh_frame_hdr, data-relative
means relative to the start of that section... */
ui->di_cache.u.rti.segbase = ((load_base + peh_hdr->p_vaddr)
+ ((unw_word_t) hdr - (unw_word_t) ui->ei.image
- peh_hdr->p_offset));
return &ui->di_cache;
}
#elif UNW_TARGET_X86_64
HIDDEN unw_dyn_info_t *
_UPTi_find_unwind_table (struct UPT_info *ui, unw_addr_space_t as,
char *path, unw_word_t segbase, unw_word_t mapoff)
{
/* fix me */
return NULL;
}
#endif /* UNW_TARGET_X86_64 */
#endif /* UNW_TARGET_X86 || UNW_TARGET_X86_64 || UNW_TARGET_HPPA*/
static unw_dyn_info_t *
get_unwind_info (struct UPT_info *ui, unw_addr_space_t as, unw_word_t ip)
@ -198,6 +340,8 @@ get_unwind_info (struct UPT_info *ui, unw_addr_space_t as, unw_word_t ip)
if (tdep_get_elf_image (&ui->ei, ui->pid, ip, &segbase, &mapoff) < 0)
return NULL;
/* Here, SEGBASE is the starting-address of the (mmap'ped) segment
which covers the IP we're looking for. */
di = _UPTi_find_unwind_table (ui, as, path, segbase, mapoff);
if (!di
/* This can happen in corner cases where dynamically generated