Dwarf_Die *
dwarf_cu_die (Dwarf_CU *cu, Dwarf_Die *result, Dwarf_Half *versionp,
Dwarf_Off *abbrev_offsetp, uint8_t *address_sizep,
uint8_t *offset_sizep, uint64_t *type_signaturep,
Dwarf_Off *type_offsetp)
{
if (cu == NULL)
return NULL;
*result = CUDIE (cu);
if (versionp != NULL)
*versionp = cu->version;
if (abbrev_offsetp != NULL)
*abbrev_offsetp = cu->orig_abbrev_offset;
if (address_sizep != NULL)
*address_sizep = cu->address_size;
if (offset_sizep != NULL)
*offset_sizep = cu->offset_size;
if (type_signaturep != NULL)
*type_signaturep = cu->type_sig8;
if (type_offsetp != NULL)
*type_offsetp = cu->type_offset;
return result;
}
int
dwarf_entry_breakpoints (Dwarf_Die *die, Dwarf_Addr **bkpts)
{
int nbkpts = 0;
*bkpts = NULL;
/* Fetch the CU's line records to look for this DIE's addresses. */
Dwarf_Die cudie = CUDIE (die->cu);
Dwarf_Lines *lines;
size_t nlines;
if (INTUSE(dwarf_getsrclines) (&cudie, &lines, &nlines) < 0)
{
int error = INTUSE (dwarf_errno) ();
if (error == 0) /* CU has no DW_AT_stmt_list. */
return entrypc_bkpt (die, bkpts, &nbkpts);
__libdw_seterrno (error);
return -1;
}
/* Search each contiguous address range for DWARF prologue_end markers. */
Dwarf_Addr base;
Dwarf_Addr begin;
Dwarf_Addr end;
ptrdiff_t offset = INTUSE(dwarf_ranges) (die, 0, &base, &begin, &end);
if (offset < 0)
return -1;
/* Most often there is a single contiguous PC range for the DIE. */
if (offset == 1)
return search_range (begin, end, true, true, lines, nlines, bkpts, &nbkpts)
?: entrypc_bkpt (die, bkpts, &nbkpts);
Dwarf_Addr lowpc = (Dwarf_Addr) -1l;
Dwarf_Addr highpc = (Dwarf_Addr) -1l;
while (offset > 0)
{
/* We have an address range entry. */
if (search_range (begin, end, true, false,
lines, nlines, bkpts, &nbkpts) < 0)
return -1;
if (begin < lowpc)
{
lowpc = begin;
highpc = end;
}
offset = INTUSE(dwarf_ranges) (die, offset, &base, &begin, &end);
}
/* If we didn't find any proper DWARF markers, then look in the
lowest-addressed range for an ad hoc marker. Failing that,
fall back to just using the entrypc value. */
return (nbkpts
?: (lowpc == (Dwarf_Addr) -1l ? 0
: search_range (lowpc, highpc, false, true,
lines, nlines, bkpts, &nbkpts))
?: entrypc_bkpt (die, bkpts, &nbkpts));
}
int
dwarf_getlocation_implicit_value (Dwarf_Attribute *attr, const Dwarf_Op *op,
Dwarf_Block *return_block)
{
if (attr == NULL)
return -1;
struct loc_block_s fake = { .addr = (void *) op };
struct loc_block_s **found = tfind (&fake, &attr->cu->locs, loc_compare);
if (unlikely (found == NULL))
{
__libdw_seterrno (DWARF_E_NO_BLOCK);
return -1;
}
return_block->length = (*found)->length;
return_block->data = (*found)->data;
return 0;
}
/* DW_AT_data_member_location can be a constant as well as a loclistptr.
Only data[48] indicate a loclistptr. */
static int
check_constant_offset (Dwarf_Attribute *attr,
Dwarf_Op **llbuf, size_t *listlen)
{
if (attr->code != DW_AT_data_member_location)
return 1;
switch (attr->form)
{
/* Punt for any non-constant form. */
default:
return 1;
case DW_FORM_data1:
case DW_FORM_data2:
case DW_FORM_data4:
case DW_FORM_data8:
case DW_FORM_sdata:
case DW_FORM_udata:
break;
}
/* Check whether we already cached this location. */
struct loc_s fake = { .addr = attr->valp };
struct loc_s **found = tfind (&fake, &attr->cu->locs, loc_compare);
if (found == NULL)
{
Dwarf_Word offset;
if (INTUSE(dwarf_formudata) (attr, &offset) != 0)
return -1;
Dwarf_Op *result = libdw_alloc (attr->cu->dbg,
Dwarf_Op, sizeof (Dwarf_Op), 1);
result->atom = DW_OP_plus_uconst;
result->number = offset;
result->number2 = 0;
result->offset = 0;
/* Insert a record in the search tree so we can find it again later. */
struct loc_s *newp = libdw_alloc (attr->cu->dbg,
struct loc_s, sizeof (struct loc_s),
1);
newp->addr = attr->valp;
newp->loc = result;
newp->nloc = 1;
found = tsearch (newp, &attr->cu->locs, loc_compare);
}
assert ((*found)->nloc == 1);
if (llbuf != NULL)
{
*llbuf = (*found)->loc;
*listlen = 1;
}
return 0;
}
int
internal_function
__libdw_intern_expression (Dwarf *dbg, bool other_byte_order,
unsigned int address_size, unsigned int ref_size,
void **cache, const Dwarf_Block *block,
bool cfap, bool valuep,
Dwarf_Op **llbuf, size_t *listlen, int sec_index)
{
/* Empty location expressions don't have any ops to intern. */
if (block->length == 0)
{
*listlen = 0;
return 0;
}
/* Check whether we already looked at this list. */
struct loc_s fake = { .addr = block->data };
struct loc_s **found = tfind (&fake, cache, loc_compare);
if (found != NULL)
{
/* We already saw it. */
*llbuf = (*found)->loc;
*listlen = (*found)->nloc;
if (valuep)
{
assert (*listlen > 1);
assert ((*llbuf)[*listlen - 1].atom == DW_OP_stack_value);
}
return 0;
}
const unsigned char *data = block->data;
const unsigned char *const end_data = data + block->length;
const struct { bool other_byte_order; } bo = { other_byte_order };
struct loclist *loclist = NULL;
unsigned int n = 0;
/* Stack allocate at most this many locs. */
#define MAX_STACK_LOCS 256
struct loclist stack_locs[MAX_STACK_LOCS];
#define NEW_LOC() ({ struct loclist *ll; \
ll = (likely (n < MAX_STACK_LOCS) \
? &stack_locs[n] \
: malloc (sizeof (struct loclist))); \
if (unlikely (ll == NULL)) \
goto nomem; \
n++; \
ll->next = loclist; \
loclist = ll; \
ll; })
if (cfap)
{
/* Synthesize the operation to push the CFA before the expression. */
struct loclist *newloc = NEW_LOC ();
newloc->atom = DW_OP_call_frame_cfa;
newloc->number = 0;
newloc->number2 = 0;
newloc->offset = -1;
}
/* Decode the opcodes. It is possible in some situations to have a
block of size zero. */
while (data < end_data)
{
struct loclist *newloc;
newloc = NEW_LOC ();
newloc->number = 0;
newloc->number2 = 0;
newloc->offset = data - block->data;
switch ((newloc->atom = *data++))
{
case DW_OP_addr:
/* Address, depends on address size of CU. */
if (dbg == NULL)
{
// XXX relocation?
if (address_size == 4)
{
if (unlikely (data + 4 > end_data))
goto invalid;
else
newloc->number = read_4ubyte_unaligned_inc (&bo, data);
}
else
{
if (unlikely (data + 8 > end_data))
goto invalid;
else
newloc->number = read_8ubyte_unaligned_inc (&bo, data);
}
}
else if (__libdw_read_address_inc (dbg, sec_index, &data,
address_size, &newloc->number))
goto invalid;
break;
case DW_OP_call_ref:
/* DW_FORM_ref_addr, depends on offset size of CU. */
if (dbg == NULL || __libdw_read_offset_inc (dbg, sec_index, &data,
ref_size,
&newloc->number,
IDX_debug_info, 0))
goto invalid;
break;
case DW_OP_deref:
case DW_OP_dup:
case DW_OP_drop:
case DW_OP_over:
case DW_OP_swap:
case DW_OP_rot:
case DW_OP_xderef:
case DW_OP_abs:
case DW_OP_and:
case DW_OP_div:
case DW_OP_minus:
case DW_OP_mod:
case DW_OP_mul:
case DW_OP_neg:
case DW_OP_not:
case DW_OP_or:
case DW_OP_plus:
case DW_OP_shl:
case DW_OP_shr:
case DW_OP_shra:
case DW_OP_xor:
case DW_OP_eq:
case DW_OP_ge:
case DW_OP_gt:
case DW_OP_le:
case DW_OP_lt:
case DW_OP_ne:
case DW_OP_lit0 ... DW_OP_lit31:
case DW_OP_reg0 ... DW_OP_reg31:
case DW_OP_nop:
case DW_OP_push_object_address:
case DW_OP_call_frame_cfa:
case DW_OP_form_tls_address:
case DW_OP_GNU_push_tls_address:
case DW_OP_stack_value:
/* No operand. */
break;
case DW_OP_const1u:
case DW_OP_pick:
case DW_OP_deref_size:
case DW_OP_xderef_size:
if (unlikely (data >= end_data))
{
invalid:
__libdw_seterrno (DWARF_E_INVALID_DWARF);
returnmem:
/* Free any dynamicly allocated loclists, if any. */
while (n > MAX_STACK_LOCS)
{
struct loclist *loc = loclist;
loclist = loc->next;
free (loc);
n--;
}
return -1;
}
newloc->number = *data++;
break;
case DW_OP_const1s:
if (unlikely (data >= end_data))
goto invalid;
newloc->number = *((int8_t *) data);
++data;
break;
case DW_OP_const2u:
if (unlikely (data + 2 > end_data))
goto invalid;
newloc->number = read_2ubyte_unaligned_inc (&bo, data);
break;
case DW_OP_const2s:
case DW_OP_skip:
case DW_OP_bra:
case DW_OP_call2:
if (unlikely (data + 2 > end_data))
goto invalid;
newloc->number = read_2sbyte_unaligned_inc (&bo, data);
break;
case DW_OP_const4u:
if (unlikely (data + 4 > end_data))
goto invalid;
newloc->number = read_4ubyte_unaligned_inc (&bo, data);
break;
case DW_OP_const4s:
case DW_OP_call4:
case DW_OP_GNU_parameter_ref:
if (unlikely (data + 4 > end_data))
goto invalid;
newloc->number = read_4sbyte_unaligned_inc (&bo, data);
break;
case DW_OP_const8u:
if (unlikely (data + 8 > end_data))
goto invalid;
newloc->number = read_8ubyte_unaligned_inc (&bo, data);
break;
case DW_OP_const8s:
if (unlikely (data + 8 > end_data))
goto invalid;
newloc->number = read_8sbyte_unaligned_inc (&bo, data);
break;
case DW_OP_constu:
case DW_OP_plus_uconst:
case DW_OP_regx:
case DW_OP_piece:
case DW_OP_GNU_convert:
case DW_OP_GNU_reinterpret:
get_uleb128 (newloc->number, data, end_data);
break;
case DW_OP_consts:
case DW_OP_breg0 ... DW_OP_breg31:
case DW_OP_fbreg:
get_sleb128 (newloc->number, data, end_data);
break;
case DW_OP_bregx:
get_uleb128 (newloc->number, data, end_data);
if (unlikely (data >= end_data))
goto invalid;
get_sleb128 (newloc->number2, data, end_data);
break;
case DW_OP_bit_piece:
case DW_OP_GNU_regval_type:
get_uleb128 (newloc->number, data, end_data);
if (unlikely (data >= end_data))
goto invalid;
get_uleb128 (newloc->number2, data, end_data);
break;
case DW_OP_implicit_value:
case DW_OP_GNU_entry_value:
/* This cannot be used in a CFI expression. */
if (unlikely (dbg == NULL))
goto invalid;
/* start of block inc. len. */
newloc->number2 = (Dwarf_Word) (uintptr_t) data;
get_uleb128 (newloc->number, data, end_data); /* Block length. */
if (unlikely ((Dwarf_Word) (end_data - data) < newloc->number))
goto invalid;
data += newloc->number; /* Skip the block. */
break;
case DW_OP_GNU_implicit_pointer:
/* DW_FORM_ref_addr, depends on offset size of CU. */
if (dbg == NULL || __libdw_read_offset_inc (dbg, sec_index, &data,
ref_size,
&newloc->number,
IDX_debug_info, 0))
goto invalid;
if (unlikely (data >= end_data))
goto invalid;
get_uleb128 (newloc->number2, data, end_data); /* Byte offset. */
break;
case DW_OP_GNU_deref_type:
if (unlikely (data + 1 >= end_data))
goto invalid;
newloc->number = *data++;
get_uleb128 (newloc->number2, data, end_data);
break;
case DW_OP_GNU_const_type:
{
size_t size;
get_uleb128 (newloc->number, data, end_data);
if (unlikely (data >= end_data))
goto invalid;
/* start of block inc. len. */
newloc->number2 = (Dwarf_Word) (uintptr_t) data;
size = *data++;
if (unlikely ((Dwarf_Word) (end_data - data) < size))
goto invalid;
data += size; /* Skip the block. */
}
break;
default:
goto invalid;
}
}
if (unlikely (n == 0))
{
/* This is not allowed.
It would mean an empty location expression, which we handled
already as a special case above. */
goto invalid;
}
if (valuep)
{
struct loclist *newloc = NEW_LOC ();
newloc->atom = DW_OP_stack_value;
newloc->number = 0;
newloc->number2 = 0;
newloc->offset = data - block->data;
}
/* Allocate the array. */
Dwarf_Op *result;
if (dbg != NULL)
result = libdw_alloc (dbg, Dwarf_Op, sizeof (Dwarf_Op), n);
else
{
result = malloc (sizeof *result * n);
if (result == NULL)
{
nomem:
__libdw_seterrno (DWARF_E_NOMEM);
goto returnmem;
}
}
/* Store the result. */
*llbuf = result;
*listlen = n;
do
{
/* We populate the array from the back since the list is backwards. */
--n;
result[n].atom = loclist->atom;
result[n].number = loclist->number;
result[n].number2 = loclist->number2;
result[n].offset = loclist->offset;
if (result[n].atom == DW_OP_implicit_value)
store_implicit_value (dbg, cache, &result[n]);
struct loclist *loc = loclist;
loclist = loclist->next;
if (unlikely (n + 1 > MAX_STACK_LOCS))
free (loc);
}
while (n > 0);
/* Insert a record in the search tree so that we can find it again later. */
struct loc_s *newp;
if (dbg != NULL)
newp = libdw_alloc (dbg, struct loc_s, sizeof (struct loc_s), 1);
else
{
newp = malloc (sizeof *newp);
if (newp == NULL)
{
free (result);
goto nomem;
}
}
newp->addr = block->data;
newp->loc = result;
newp->nloc = *listlen;
(void) tsearch (newp, cache, loc_compare);
/* We did it. */
return 0;
}
static int
getlocation (struct Dwarf_CU *cu, const Dwarf_Block *block,
Dwarf_Op **llbuf, size_t *listlen, int sec_index)
{
/* Empty location expressions don't have any ops to intern.
Note that synthetic empty_cu doesn't have an associated DWARF dbg. */
if (block->length == 0)
{
*listlen = 0;
return 0;
}
return __libdw_intern_expression (cu->dbg, cu->dbg->other_byte_order,
cu->address_size, (cu->version == 2
? cu->address_size
: cu->offset_size),
&cu->locs, block,
false, false,
llbuf, listlen, sec_index);
}
int
dwarf_getlocation (Dwarf_Attribute *attr, Dwarf_Op **llbuf, size_t *listlen)
{
if (! attr_ok (attr))
return -1;
int result = check_constant_offset (attr, llbuf, listlen);
if (result != 1)
return result;
/* If it has a block form, it's a single location expression. */
Dwarf_Block block;
if (INTUSE(dwarf_formblock) (attr, &block) != 0)
return -1;
return getlocation (attr->cu, &block, llbuf, listlen, cu_sec_idx (attr->cu));
}
static int
attr_base_address (Dwarf_Attribute *attr, Dwarf_Addr *basep)
{
/* Fetch the CU's base address. */
Dwarf_Die cudie = CUDIE (attr->cu);
/* Find the base address of the compilation unit. It will
normally be specified by DW_AT_low_pc. In DWARF-3 draft 4,
the base address could be overridden by DW_AT_entry_pc. It's
been removed, but GCC emits DW_AT_entry_pc and not DW_AT_lowpc
for compilation units with discontinuous ranges. */
Dwarf_Attribute attr_mem;
if (unlikely (INTUSE(dwarf_lowpc) (&cudie, basep) != 0)
&& INTUSE(dwarf_formaddr) (INTUSE(dwarf_attr) (&cudie,
DW_AT_entry_pc,
&attr_mem),
basep) != 0)
{
if (INTUSE(dwarf_errno) () != 0)
return -1;
/* The compiler provided no base address when it should
have. Buggy GCC does this when it used absolute
addresses in the location list and no DW_AT_ranges. */
*basep = 0;
}
return 0;
}
static int
getlocation (struct Dwarf_CU *cu, const Dwarf_Block *block,
Dwarf_Op **llbuf, size_t *listlen)
{
Dwarf *dbg = cu->dbg;
/* Check whether we already looked at this list. */
struct loc_s fake = { .addr = block->data };
struct loc_s **found = tfind (&fake, &cu->locs, loc_compare);
if (found != NULL)
{
/* We already saw it. */
*llbuf = (*found)->loc;
*listlen = (*found)->nloc;
return 0;
}
const unsigned char *data = block->data;
const unsigned char *const end_data = data + block->length;
struct loclist *loclist = NULL;
unsigned int n = 0;
/* Decode the opcodes. It is possible in some situations to have a
block of size zero. */
while (data < end_data)
{
struct loclist *newloc;
newloc = (struct loclist *) alloca (sizeof (struct loclist));
newloc->number = 0;
newloc->number2 = 0;
newloc->offset = data - block->data;
newloc->next = loclist;
loclist = newloc;
++n;
switch ((newloc->atom = *data++))
{
case DW_OP_addr:
/* Address, depends on address size of CU. */
if (cu->address_size == 4)
{
if (unlikely (data + 4 > end_data))
{
invalid:
__libdw_seterrno (DWARF_E_INVALID_DWARF);
return -1;
}
newloc->number = read_4ubyte_unaligned_inc (dbg, data);
}
else
{
if (unlikely (data + 8 > end_data))
goto invalid;
newloc->number = read_8ubyte_unaligned_inc (dbg, data);
}
break;
case DW_OP_deref:
case DW_OP_dup:
case DW_OP_drop:
case DW_OP_over:
case DW_OP_swap:
case DW_OP_rot:
case DW_OP_xderef:
case DW_OP_abs:
case DW_OP_and:
case DW_OP_div:
case DW_OP_minus:
case DW_OP_mod:
case DW_OP_mul:
case DW_OP_neg:
case DW_OP_not:
case DW_OP_or:
case DW_OP_plus:
case DW_OP_shl:
case DW_OP_shr:
case DW_OP_shra:
case DW_OP_xor:
case DW_OP_eq:
case DW_OP_ge:
case DW_OP_gt:
case DW_OP_le:
case DW_OP_lt:
case DW_OP_ne:
case DW_OP_lit0 ... DW_OP_lit31:
case DW_OP_reg0 ... DW_OP_reg31:
case DW_OP_nop:
case DW_OP_push_object_address:
case DW_OP_call_ref:
/* No operand. */
break;
case DW_OP_const1u:
case DW_OP_pick:
case DW_OP_deref_size:
case DW_OP_xderef_size:
if (unlikely (data >= end_data))
goto invalid;
newloc->number = *data++;
break;
case DW_OP_const1s:
if (unlikely (data >= end_data))
goto invalid;
newloc->number = *((int8_t *) data);
++data;
break;
case DW_OP_const2u:
if (unlikely (data + 2 > end_data))
goto invalid;
newloc->number = read_2ubyte_unaligned_inc (dbg, data);
break;
case DW_OP_const2s:
case DW_OP_skip:
case DW_OP_bra:
case DW_OP_call2:
if (unlikely (data + 2 > end_data))
goto invalid;
newloc->number = read_2sbyte_unaligned_inc (dbg, data);
break;
case DW_OP_const4u:
if (unlikely (data + 4 > end_data))
goto invalid;
newloc->number = read_4ubyte_unaligned_inc (dbg, data);
break;
case DW_OP_const4s:
case DW_OP_call4:
if (unlikely (data + 4 > end_data))
goto invalid;
newloc->number = read_4sbyte_unaligned_inc (dbg, data);
break;
case DW_OP_const8u:
if (unlikely (data + 8 > end_data))
goto invalid;
newloc->number = read_8ubyte_unaligned_inc (dbg, data);
break;
case DW_OP_const8s:
if (unlikely (data + 8 > end_data))
goto invalid;
newloc->number = read_8sbyte_unaligned_inc (dbg, data);
break;
case DW_OP_constu:
case DW_OP_plus_uconst:
case DW_OP_regx:
case DW_OP_piece:
/* XXX Check size. */
get_uleb128 (newloc->number, data);
break;
case DW_OP_consts:
case DW_OP_breg0 ... DW_OP_breg31:
case DW_OP_fbreg:
/* XXX Check size. */
get_sleb128 (newloc->number, data);
break;
case DW_OP_bregx:
/* XXX Check size. */
get_uleb128 (newloc->number, data);
get_sleb128 (newloc->number2, data);
break;
default:
goto invalid;
}
}
if (unlikely (n == 0))
{
/* This is not allowed.
XXX Is it? */
goto invalid;
}
/* Allocate the array. */
Dwarf_Op *result = libdw_alloc (dbg, Dwarf_Op, sizeof (Dwarf_Op), n);
/* Store the result. */
*llbuf = result;
*listlen = n;
do
{
/* We populate the array from the back since the list is
backwards. */
--n;
result[n].atom = loclist->atom;
result[n].number = loclist->number;
result[n].number2 = loclist->number2;
result[n].offset = loclist->offset;
loclist = loclist->next;
}
while (n > 0);
/* Insert a record in the search tree so that we can find it again
later. */
struct loc_s *newp = libdw_alloc (dbg, struct loc_s, sizeof (struct loc_s),
1);
newp->addr = block->data;
newp->loc = result;
newp->nloc = *listlen;
(void) tsearch (newp, &cu->locs, loc_compare);
/* We did it. */
return 0;
}
int
dwarf_getlocation (attr, llbuf, listlen)
Dwarf_Attribute *attr;
Dwarf_Op **llbuf;
size_t *listlen;
{
if (! attr_ok (attr))
return -1;
/* If it has a block form, it's a single location expression. */
Dwarf_Block block;
if (INTUSE(dwarf_formblock) (attr, &block) != 0)
return -1;
return getlocation (attr->cu, &block, llbuf, listlen);
}
int
dwarf_getlocation_addr (attr, address, llbufs, listlens, maxlocs)
Dwarf_Attribute *attr;
Dwarf_Addr address;
Dwarf_Op **llbufs;
size_t *listlens;
size_t maxlocs;
{
if (! attr_ok (attr))
return -1;
if (llbufs == NULL)
maxlocs = SIZE_MAX;
/* If it has a block form, it's a single location expression. */
Dwarf_Block block;
if (INTUSE(dwarf_formblock) (attr, &block) == 0)
{
if (maxlocs == 0)
return 0;
if (llbufs != NULL &&
getlocation (attr->cu, &block, &llbufs[0], &listlens[0]) != 0)
return -1;
return listlens[0] == 0 ? 0 : 1;
}
int error = INTUSE(dwarf_errno) ();
if (unlikely (error != DWARF_E_NO_BLOCK))
{
__libdw_seterrno (error);
return -1;
}
/* Must have the form data4 or data8 which act as an offset. */
Dwarf_Word offset;
if (unlikely (INTUSE(dwarf_formudata) (attr, &offset) != 0))
return -1;
const Elf_Data *d = attr->cu->dbg->sectiondata[IDX_debug_loc];
if (unlikely (d == NULL))
{
__libdw_seterrno (DWARF_E_NO_LOCLIST);
return -1;
}
Dwarf_Addr base = (Dwarf_Addr) -1;
unsigned char *readp = d->d_buf + offset;
size_t got = 0;
while (got < maxlocs)
{
if ((unsigned char *) d->d_buf + d->d_size - readp
< attr->cu->address_size * 2)
{
invalid:
__libdw_seterrno (DWARF_E_INVALID_DWARF);
return -1;
}
Dwarf_Addr begin;
Dwarf_Addr end;
if (attr->cu->address_size == 8)
{
begin = read_8ubyte_unaligned_inc (attr->cu->dbg, readp);
end = read_8ubyte_unaligned_inc (attr->cu->dbg, readp);
if (begin == (Elf64_Addr) -1l) /* Base address entry. */
{
base = end;
if (unlikely (base == (Dwarf_Addr) -1))
goto invalid;
continue;
}
}
else
{
begin = read_4ubyte_unaligned_inc (attr->cu->dbg, readp);
end = read_4ubyte_unaligned_inc (attr->cu->dbg, readp);
if (begin == (Elf32_Addr) -1) /* Base address entry. */
{
base = end;
continue;
}
}
if (begin == 0 && end == 0) /* End of list entry. */
break;
if ((unsigned char *) d->d_buf + d->d_size - readp < 2)
goto invalid;
/* We have a location expression. */
block.length = read_2ubyte_unaligned_inc (attr->cu->dbg, readp);
block.data = readp;
if ((unsigned char *) d->d_buf + d->d_size - readp
< (ptrdiff_t) block.length)
goto invalid;
readp += block.length;
if (base == (Dwarf_Addr) -1)
{
/* Fetch the CU's base address. */
Dwarf_Die cudie = CUDIE (attr->cu);
/* Find the base address of the compilation unit. It will
normally be specified by DW_AT_low_pc. In DWARF-3 draft 4,
the base address could be overridden by DW_AT_entry_pc. It's
been removed, but GCC emits DW_AT_entry_pc and not DW_AT_lowpc
for compilation units with discontinuous ranges. */
Dwarf_Attribute attr_mem;
if (unlikely (INTUSE(dwarf_lowpc) (&cudie, &base) != 0)
&& INTUSE(dwarf_formaddr) (INTUSE(dwarf_attr) (&cudie,
DW_AT_entry_pc,
&attr_mem),
&base) != 0)
{
if (INTUSE(dwarf_errno) () != 0)
return -1;
/* The compiler provided no base address when it should
have. Buggy GCC does this when it used absolute
addresses in the location list and no DW_AT_ranges. */
base = 0;
}
}
if (address >= base + begin && address < base + end)
{
/* This one matches the address. */
if (llbufs != NULL
&& unlikely (getlocation (attr->cu, &block,
&llbufs[got], &listlens[got]) != 0))
return -1;
++got;
}
}
return got;
}
/* Find the containing CU's files. */
static int
getfiles (Dwarf_Die *die, Dwarf_Files **files)
{
return INTUSE(dwarf_getsrcfiles) (&CUDIE (die->cu), files, NULL);
}
ptrdiff_t
dwarf_ranges (Dwarf_Die *die, ptrdiff_t offset, Dwarf_Addr *basep,
Dwarf_Addr *startp, Dwarf_Addr *endp)
{
if (die == NULL)
return -1;
if (offset == 0
/* Usually there is a single contiguous range. */
&& INTUSE(dwarf_highpc) (die, endp) == 0
&& INTUSE(dwarf_lowpc) (die, startp) == 0)
/* A offset into .debug_ranges will never be 1, it must be at least a
multiple of 4. So we can return 1 as a special case value to mark
there are no ranges to look for on the next call. */
return 1;
if (offset == 1)
return 0;
/* We have to look for a noncontiguous range. */
const Elf_Data *d = die->cu->dbg->sectiondata[IDX_debug_ranges];
if (d == NULL && offset != 0)
{
__libdw_seterrno (DWARF_E_NO_DEBUG_RANGES);
return -1;
}
unsigned char *readp;
unsigned char *readendp;
if (offset == 0)
{
Dwarf_Attribute attr_mem;
Dwarf_Attribute *attr = INTUSE(dwarf_attr) (die, DW_AT_ranges,
&attr_mem);
if (attr == NULL)
/* No PC attributes in this DIE at all, so an empty range list. */
return 0;
Dwarf_Word start_offset;
if ((readp = __libdw_formptr (attr, IDX_debug_ranges,
DWARF_E_NO_DEBUG_RANGES,
&readendp, &start_offset)) == NULL)
return -1;
offset = start_offset;
assert ((Dwarf_Word) offset == start_offset);
/* Fetch the CU's base address. */
Dwarf_Die cudie = CUDIE (attr->cu);
/* Find the base address of the compilation unit. It will
normally be specified by DW_AT_low_pc. In DWARF-3 draft 4,
the base address could be overridden by DW_AT_entry_pc. It's
been removed, but GCC emits DW_AT_entry_pc and not DW_AT_lowpc
for compilation units with discontinuous ranges. */
if (unlikely (INTUSE(dwarf_lowpc) (&cudie, basep) != 0)
&& INTUSE(dwarf_formaddr) (INTUSE(dwarf_attr) (&cudie,
DW_AT_entry_pc,
&attr_mem),
basep) != 0)
*basep = (Dwarf_Addr) -1;
}
else
{
if (__libdw_offset_in_section (die->cu->dbg,
IDX_debug_ranges, offset, 1))
return -1l;
readp = d->d_buf + offset;
readendp = d->d_buf + d->d_size;
}
next:
if (readendp - readp < die->cu->address_size * 2)
goto invalid;
Dwarf_Addr begin;
Dwarf_Addr end;
switch (__libdw_read_begin_end_pair_inc (die->cu->dbg, IDX_debug_ranges,
&readp, die->cu->address_size,
&begin, &end, basep))
{
case 0:
break;
case 1:
goto next;
case 2:
return 0;
default:
return -1l;
}
/* We have an address range entry. Check that we have a base. */
if (*basep == (Dwarf_Addr) -1)
{
if (INTUSE(dwarf_errno) () == 0)
{
invalid:
__libdw_seterrno (DWARF_E_INVALID_DWARF);
}
return -1;
}
*startp = *basep + begin;
*endp = *basep + end;
return readp - (unsigned char *) d->d_buf;
}
static int
array_size (Dwarf_Die *die, Dwarf_Word *size,
Dwarf_Attribute *attr_mem, Dwarf_Die *type_mem)
{
Dwarf_Word eltsize;
if (INTUSE(dwarf_aggregate_size) (get_type (die, attr_mem, type_mem),
&eltsize) != 0)
return -1;
/* An array can have DW_TAG_subrange_type or DW_TAG_enumeration_type
children instead that give the size of each dimension. */
Dwarf_Die child;
if (INTUSE(dwarf_child) (die, &child) != 0)
return -1;
bool any = false;
Dwarf_Word total = 0;
do
{
Dwarf_Word count;
switch (INTUSE(dwarf_tag) (&child))
{
case DW_TAG_subrange_type:
/* This has either DW_AT_count or DW_AT_upper_bound. */
if (INTUSE(dwarf_attr_integrate) (&child, DW_AT_count,
attr_mem) != NULL)
{
if (INTUSE(dwarf_formudata) (attr_mem, &count) != 0)
return -1;
}
else
{
Dwarf_Sword upper;
Dwarf_Sword lower;
if (INTUSE(dwarf_formsdata) (INTUSE(dwarf_attr_integrate)
(&child, DW_AT_upper_bound,
attr_mem), &upper) != 0)
return -1;
/* Having DW_AT_lower_bound is optional. */
if (INTUSE(dwarf_attr_integrate) (&child, DW_AT_lower_bound,
attr_mem) != NULL)
{
if (INTUSE(dwarf_formsdata) (attr_mem, &lower) != 0)
return -1;
}
else
{
/* Determine default lower bound from language,
as per "4.12 Subrange Type Entries". */
Dwarf_Die cu = CUDIE (die->cu);
switch (INTUSE(dwarf_srclang) (&cu))
{
case DW_LANG_C:
case DW_LANG_C89:
case DW_LANG_C99:
case DW_LANG_C_plus_plus:
case DW_LANG_ObjC:
case DW_LANG_ObjC_plus_plus:
case DW_LANG_Java:
case DW_LANG_D:
case DW_LANG_UPC:
lower = 0;
break;
case DW_LANG_Ada83:
case DW_LANG_Ada95:
case DW_LANG_Cobol74:
case DW_LANG_Cobol85:
case DW_LANG_Fortran77:
case DW_LANG_Fortran90:
case DW_LANG_Fortran95:
case DW_LANG_Pascal83:
case DW_LANG_Modula2:
case DW_LANG_PL1:
lower = 1;
break;
default:
return -1;
}
}
if (unlikely (lower > upper))
return -1;
count = upper - lower + 1;
}
break;
case DW_TAG_enumeration_type:
/* We have to find the DW_TAG_enumerator child with the
highest value to know the array's element count. */
count = 0;
Dwarf_Die enum_child;
int has_children = INTUSE(dwarf_child) (die, &enum_child);
if (has_children < 0)
return -1;
if (has_children > 0)
do
if (INTUSE(dwarf_tag) (&enum_child) == DW_TAG_enumerator)
{
Dwarf_Word value;
if (INTUSE(dwarf_formudata) (INTUSE(dwarf_attr_integrate)
(&enum_child, DW_AT_const_value,
attr_mem), &value) != 0)
return -1;
if (value >= count)
count = value + 1;
}
while (INTUSE(dwarf_siblingof) (&enum_child, &enum_child) > 0);
break;
default:
continue;
}
/* This is a subrange_type or enumeration_type and we've set COUNT.
Now determine the stride for this array dimension. */
Dwarf_Word stride = eltsize;
if (INTUSE(dwarf_attr_integrate) (&child, DW_AT_byte_stride,
attr_mem) != NULL)
{
if (INTUSE(dwarf_formudata) (attr_mem, &stride) != 0)
return -1;
}
else if (INTUSE(dwarf_attr_integrate) (&child, DW_AT_bit_stride,
attr_mem) != NULL)
{
if (INTUSE(dwarf_formudata) (attr_mem, &stride) != 0)
return -1;
if (stride % 8) /* XXX maybe compute in bits? */
return -1;
stride /= 8;
}
any = true;
total += stride * count;
}
while (INTUSE(dwarf_siblingof) (&child, &child) == 0);
if (!any)
return -1;
*size = total;
return 0;
}
