/* Given a Dwarf_Block that represents a location expression,
this function returns a pointer to a Dwarf_Locdesc struct
that has its ld_cents field set to the number of location
operators in the block, and its ld_s field pointing to a
contiguous block of Dwarf_Loc structs. However, the
ld_lopc and ld_hipc values are uninitialized. Returns
DW_DLV_ERROR on error.
This function assumes that the length of
the block is greater than 0. Zero length location expressions
to represent variables that have been optimized away are
handled in the calling function.
address_size, offset_size, and version_stamp are
per-CU, not per-object or per dbg.
We cannot use dbg directly to get those values.
Use for DWARF 2,3,4. Not for DWARF5.
*/
static int
_dwarf_get_locdesc(Dwarf_Debug dbg,
Dwarf_Block_c * loc_block,
Dwarf_Half address_size,
Dwarf_Half offset_size,
Dwarf_Small version_stamp,
Dwarf_Addr lowpc,
Dwarf_Addr highpc,
Dwarf_Locdesc ** locdesc_out,
Dwarf_Error * error)
{
/* Offset of current operator from start of block. */
Dwarf_Unsigned offset = 0;
/* Used to chain the Dwarf_Loc_Chain_s structs. */
Dwarf_Loc_Chain new_loc = NULL;
Dwarf_Loc_Chain prev_loc = NULL;
Dwarf_Loc_Chain head_loc = NULL;
/* Count of the number of location operators. */
Dwarf_Unsigned op_count = 0;
/* Contiguous block of Dwarf_Loc's for Dwarf_Locdesc. */
Dwarf_Loc *block_loc = 0;
/* Dwarf_Locdesc pointer to be returned. */
Dwarf_Locdesc *locdesc = 0;
Dwarf_Unsigned i = 0;
int res = 0;
/* ***** BEGIN CODE ***** */
offset = 0;
op_count = 0;
res = _dwarf_loc_block_sanity_check(dbg,loc_block,error);
if (res != DW_DLV_OK) {
return res;
}
/* OLD loop getting Loc operators. No DWARF5 */
while (offset <= loc_block->bl_len) {
Dwarf_Unsigned nextoffset = 0;
struct Dwarf_Loc_c_s temp_loc;
res = _dwarf_read_loc_expr_op(dbg,loc_block,
op_count,
version_stamp,
offset_size,
address_size,
offset,
&nextoffset,
&temp_loc,
error);
if (res == DW_DLV_ERROR) {
return res;
}
if (res == DW_DLV_NO_ENTRY) {
/* Normal end. */
break;
}
op_count++;
new_loc =
(Dwarf_Loc_Chain) _dwarf_get_alloc(dbg, DW_DLA_LOC_CHAIN, 1);
if (new_loc == NULL) {
/* Some memory may leak here. */
_dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);
return DW_DLV_ERROR;
}
/* Copying only the fields needed by DWARF 2,3,4 */
new_loc->lc_atom = temp_loc.lr_atom;
new_loc->lc_opnumber= temp_loc.lr_opnumber;
new_loc->lc_number = temp_loc.lr_number;
new_loc->lc_number2 = temp_loc.lr_number2;
new_loc->lc_offset = temp_loc.lr_offset;
offset = nextoffset;
if (head_loc == NULL)
head_loc = prev_loc = new_loc;
else {
prev_loc->lc_next = new_loc;
prev_loc = new_loc;
}
}
block_loc =
(Dwarf_Loc *) _dwarf_get_alloc(dbg, DW_DLA_LOC_BLOCK, op_count);
if (block_loc == NULL) {
/* Some memory does leak here. */
_dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);
return DW_DLV_ERROR;
}
new_loc = head_loc;
for (i = 0; i < op_count; i++) {
/* Copying only the fields needed by DWARF 2,3,4 */
(block_loc + i)->lr_atom = new_loc->lc_atom;
(block_loc + i)->lr_number = new_loc->lc_number;
(block_loc + i)->lr_number2 = new_loc->lc_number2;
(block_loc + i)->lr_offset = new_loc->lc_offset;
prev_loc = new_loc;
new_loc = prev_loc->lc_next;
dwarf_dealloc(dbg, prev_loc, DW_DLA_LOC_CHAIN);
}
locdesc =
(Dwarf_Locdesc *) _dwarf_get_alloc(dbg, DW_DLA_LOCDESC, 1);
if (locdesc == NULL) {
_dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);
return DW_DLV_ERROR;
}
locdesc->ld_cents = op_count;
locdesc->ld_s = block_loc;
locdesc->ld_from_loclist = loc_block->bl_from_loclist;
locdesc->ld_section_offset = loc_block->bl_section_offset;
locdesc->ld_lopc = lowpc;
locdesc->ld_hipc = highpc;
*locdesc_out = locdesc;
return DW_DLV_OK;
}
static int
_dwarf_get_locdesc_c(Dwarf_Debug dbg,
Dwarf_Unsigned locdesc_index,
Dwarf_Loc_Head_c loc_head,
Dwarf_Block_c * loc_block,
Dwarf_Half address_size,
Dwarf_Half offset_size,
Dwarf_Small version_stamp,
Dwarf_Addr lowpc,
Dwarf_Addr highpc,
Dwarf_Error * error)
{
/* Offset of current operator from start of block. */
Dwarf_Unsigned offset = 0;
/* Used to chain the Dwarf_Loc_Chain_s structs. */
Dwarf_Loc_Chain new_loc = NULL;
Dwarf_Loc_Chain prev_loc = NULL;
Dwarf_Loc_Chain head_loc = NULL;
Dwarf_Unsigned op_count = 0;
/* Contiguous block of Dwarf_Loc's for Dwarf_Locdesc. */
Dwarf_Loc_c block_loc = 0;
Dwarf_Locdesc_c locdesc = loc_head->ll_locdesc + locdesc_index;
Dwarf_Unsigned i = 0;
int res = 0;
Dwarf_Small *section_start = 0;
Dwarf_Unsigned section_size = 0;
Dwarf_Small *section_end = 0;
const char *section_name = 0;
Dwarf_Small *blockdataptr = 0;
/* ***** BEGIN CODE ***** */
blockdataptr = loc_block->bl_data;
res = _dwarf_what_section_are_we(dbg,
blockdataptr,§ion_name,§ion_start,
§ion_size,§ion_end,error);
if (res != DW_DLV_OK) {
_dwarf_error(dbg, error,DW_DLE_POINTER_SECTION_UNKNOWN);
return DW_DLV_ERROR;
}
res = _dwarf_loc_block_sanity_check(dbg,loc_block,error);
if (res != DW_DLV_OK) {
return res;
}
/* New loop getting Loc operators. Non DWO */
while (offset <= loc_block->bl_len) {
Dwarf_Unsigned nextoffset = 0;
struct Dwarf_Loc_c_s temp_loc;
res = _dwarf_read_loc_expr_op(dbg,loc_block,
op_count,
version_stamp,
offset_size,
address_size,
offset,
section_end,
&nextoffset,
&temp_loc,
error);
if (res == DW_DLV_ERROR) {
return res;
}
if (res == DW_DLV_NO_ENTRY) {
/* Normal end. */
break;
}
op_count++;
new_loc =
(Dwarf_Loc_Chain) _dwarf_get_alloc(dbg, DW_DLA_LOC_CHAIN, 1);
if (new_loc == NULL) {
/* Some memory may leak here. */
_dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);
return DW_DLV_ERROR;
}
/* Copying all the fields. DWARF 2,3,4,5. */
new_loc->lc_atom = temp_loc.lr_atom;
new_loc->lc_opnumber= temp_loc.lr_opnumber;
new_loc->lc_number = temp_loc.lr_number;
new_loc->lc_number2 = temp_loc.lr_number2;
new_loc->lc_number3 = temp_loc.lr_number3;
new_loc->lc_offset = temp_loc.lr_offset;
offset = nextoffset;
if (head_loc == NULL)
head_loc = prev_loc = new_loc;
else {
prev_loc->lc_next = new_loc;
prev_loc = new_loc;
}
offset = nextoffset;
}
block_loc =
(Dwarf_Loc_c ) _dwarf_get_alloc(dbg, DW_DLA_LOC_BLOCK_C,
op_count);
if (block_loc == NULL) {
/* Some memory does leak here. */
_dwarf_error(dbg, error, DW_DLE_ALLOC_FAIL);
return DW_DLV_ERROR;
}
new_loc = head_loc;
for (i = 0; i < op_count; i++) {
/* Copying only the fields needed by DWARF 2,3,4 */
(block_loc + i)->lr_atom = new_loc->lc_atom;
(block_loc + i)->lr_number = new_loc->lc_number;
(block_loc + i)->lr_number2 = new_loc->lc_number2;
(block_loc + i)->lr_number3 = new_loc->lc_number3;
(block_loc + i)->lr_offset = new_loc->lc_offset;
(block_loc + i)->lr_opnumber = new_loc->lc_opnumber;
prev_loc = new_loc;
new_loc = prev_loc->lc_next;
dwarf_dealloc(dbg, prev_loc, DW_DLA_LOC_CHAIN);
}
/* Synthesizing the DW_LLE values. */
if(highpc == 0 && lowpc == 0) {
locdesc->ld_lle_value = DW_LLE_end_of_list_entry;
} else if(lowpc == MAX_ADDR) {
locdesc->ld_lle_value = DW_LLE_base_address_selection_entry;
} else {
locdesc->ld_lle_value = DW_LLE_offset_pair_entry;
}
locdesc->ld_cents = op_count;
locdesc->ld_s = block_loc;
locdesc->ld_from_loclist = loc_block->bl_from_loclist;
locdesc->ld_section_offset = loc_block->bl_section_offset;
locdesc->ld_locdesc_offset = loc_block->bl_locdesc_offset;
locdesc->ld_lopc = lowpc;
locdesc->ld_hipc = highpc;
return DW_DLV_OK;
}
