int
dwarf_loclist_from_expr_a(Dwarf_Debug dbg, Dwarf_Ptr bytes_in,
Dwarf_Unsigned bytes_len, Dwarf_Half addr_size, Dwarf_Locdesc **llbuf,
Dwarf_Signed *listlen, Dwarf_Error *error)
{
Dwarf_Half offset_size;
Dwarf_Small version;
/*
* Obtain offset size and DWARF version from the current
* Compilation Unit or Type Unit. These values are needed
* for correctly parsing DW_OP_GNU_implicit_pointer operator.
*
* Note that dwarf_loclist_from_expr_b() should be used instead
* if the application knows correct values for offset size
* and DWARF version.
*/
if (dbg->dbg_cu_current) {
offset_size = dbg->dbg_cu_current->cu_length_size == 4 ? 4 : 8;
version = dbg->dbg_cu_current->cu_version;
} else if (dbg->dbg_tu_current) {
offset_size = dbg->dbg_tu_current->cu_length_size == 4 ? 4 : 8;
version = dbg->dbg_tu_current->cu_version;
} else {
/* Default values if no CU/TU context. */
offset_size = 4;
version = 2; /* DWARF2 */
}
return (dwarf_loclist_from_expr_b(dbg, bytes_in, bytes_len, addr_size,
offset_size, version, llbuf, listlen, error));
}
/* New April 27 2009. Adding addr_size argument for the rare
cases where an object has CUs with a different address_size.
As of 2012 we have yet another version, dwarf_loclist_from_expr_b()
with the version_stamp and offset size (length size) passed in.
*/
int
dwarf_loclist_from_expr_a(Dwarf_Debug dbg,
Dwarf_Ptr expression_in,
Dwarf_Unsigned expression_length,
Dwarf_Half addr_size,
Dwarf_Locdesc ** llbuf,
Dwarf_Signed * listlen,
Dwarf_Error * error)
{
int res;
Dwarf_Debug_InfoTypes info_reading = &dbg->de_info_reading;
Dwarf_CU_Context current_cu_context =
info_reading->de_cu_context;
Dwarf_Small version_stamp = DW_CU_VERSION2;
Dwarf_Half offset_size = dbg->de_length_size;
if (current_cu_context) {
/* This is ugly. It is not necessarily right. Due to
oddity in DW_OP_GNU_implicit_pointer, see its
implementation above.
For correctness, use dwarf_loclist_from_expr_b()
instead of dwarf_loclist_from_expr_a(). */
version_stamp = current_cu_context->cc_version_stamp;
offset_size = current_cu_context->cc_length_size;
if (version_stamp < 2) {
/* This is probably totally silly. */
version_stamp = DW_CU_VERSION2;
}
}
res = dwarf_loclist_from_expr_b(dbg,
expression_in,
expression_length,
addr_size,
offset_size,
version_stamp, /* CU context DWARF version */
llbuf,
listlen,
error);
return res;
}
