int
dwarf_loclist(Dwarf_Attribute at, Dwarf_Locdesc **llbuf,
Dwarf_Signed *listlen, Dwarf_Error *error)
{
Dwarf_Locdesc **_llbuf;
int i, ret;
ret = dwarf_loclist_n(at, &_llbuf, listlen, error);
if (ret != DW_DLV_OK)
return (ret);
/* Only return the first location description of the list. */
*llbuf = _llbuf[0];
/* Free the rest of the list. */
for (i = 1; i < *listlen; i++) {
if (_llbuf[i]->ld_s)
free(_llbuf[i]->ld_s);
free(_llbuf[i]);
}
free(_llbuf);
*listlen = 1;
return (DW_DLV_OK);
}
Dwarf_Loc dwarf_get_variable_location(Dwarf_Die die, struct dwarf_compilation_unit * unit){
Dwarf_Error error = 0;
Dwarf_Attribute *attrbuf = 0;
Dwarf_Signed attrcount = 0;
Dwarf_Unsigned i;
Dwarf_Locdesc *llbuf = 0;
Dwarf_Locdesc **llbufarray = 0;
Dwarf_Signed no_of_elements;
int lres = 0;
Dwarf_Loc first_loc;
int res = dwarf_attrlist(die,&attrbuf,&attrcount,&error);
if(res != DW_DLV_OK) {
return first_loc;
}
for(i = 0; i < attrcount ; ++i) {
Dwarf_Half aform;
res = dwarf_whatattr(attrbuf[i],&aform,&error);
if(aform == DW_AT_location) {
lres = dwarf_loclist_n(attrbuf[i], &llbufarray, &no_of_elements, &error);
if (llbufarray[0]->ld_s){
first_loc = (llbufarray[0]->ld_s)[0];
return first_loc;
}
}
}
return first_loc;
}
bool DieHolder::get_operand(int const attr, ea_t const rel_addr, Dwarf_Small const atom,
Dwarf_Unsigned *operand, bool only_locblock)
{
Dwarf_Attribute attrib = get_attr(attr);
Dwarf_Locdesc **llbuf = NULL;
Dwarf_Locdesc *locdesc = NULL;
Dwarf_Signed count = 0;
Dwarf_Error err = NULL;
DwarfDealloc dealloc(m_dbg);
bool found = false;
bool ret = false;
CHECK_DWERR2(attrib == NULL, NULL,
"retrieving an operand implies finding the attribute...");
CHECK_DWERR(dwarf_loclist_n(attrib, &llbuf, &count, &err), err,
"cannot get location descriptions");
dealloc.add(llbuf, DW_DLA_LIST);
for(Dwarf_Signed idx = 0; idx < count; ++idx)
{
locdesc = llbuf[idx];
// handle deallocation too
dealloc.add(llbuf[idx], DW_DLA_LOCDESC);
dealloc.add(llbuf[idx]->ld_s, DW_DLA_LOC_BLOCK);
if(!found)
{
// from a location block?
if(!locdesc->ld_from_loclist)
{
// no need to check the address
found = true;
}
// this loc desc is from a location list
else if(!only_locblock &&
(locdesc->ld_lopc <= rel_addr &&
locdesc->ld_hipc > rel_addr))
{
found = true;
}
}
}
if(found)
{
CHECK_DWERR2(locdesc->ld_cents != 1, NULL,
"only 1 location in a location description is supported");
Dwarf_Loc *loc = &locdesc->ld_s[0];
if(loc->lr_atom == atom)
{
*operand = loc->lr_number;
ret = true;
}
}
return ret;
}
void DieHolder::get_frame_base_offsets(OffsetAreas &offset_areas)
{
Dwarf_Attribute attrib = get_attr(DW_AT_frame_base);
Dwarf_Locdesc **llbuf = NULL;
Dwarf_Locdesc *locdesc = NULL;
Dwarf_Signed count = 0;
Dwarf_Error err = NULL;
DwarfDealloc dealloc(m_dbg);
CHECK_DWERR2(attrib == NULL, NULL,
"retrieving an operand implies finding the attribute...");
CHECK_DWERR(dwarf_loclist_n(attrib, &llbuf, &count, &err), err,
"cannot get location descriptions");
dealloc.add(llbuf, DW_DLA_LIST);
for(Dwarf_Signed idx = 0; idx < count; ++idx)
{
ea_t low_pc = 0;
ea_t high_pc = 0;
locdesc = llbuf[idx];
// handle deallocation too
dealloc.add(llbuf[idx], DW_DLA_LOCDESC);
dealloc.add(llbuf[idx]->ld_s, DW_DLA_LOC_BLOCK);
// only 1 location in a location description is supported
if(locdesc->ld_cents == 1)
{
Dwarf_Loc *loc = &locdesc->ld_s[0];
Dwarf_Small const atom = loc->lr_atom;
// from a location block?
if(!locdesc->ld_from_loclist)
{
low_pc = BADADDR;
high_pc = BADADDR;
}
// this loc desc is from a location list
else
{
low_pc = static_cast<ea_t>(locdesc->ld_lopc);
high_pc = static_cast<ea_t>(locdesc->ld_hipc);
}
// is it the right atom to get the offset from?
if(atom == DW_OP_breg4 || atom == DW_OP_breg5)
{
offset_areas.push_back(OffsetArea(low_pc, high_pc,
// operand is unsigned, but should be signed...
static_cast<sval_t>(loc->lr_number),
(atom == DW_OP_breg5)));
}
}
}
}
void DieHolder::retrieve_var(func_t *funptr, ea_t const cu_low_pc,
OffsetAreas const &offset_areas, func_type_info_t *info,
var_visitor_fun visit)
{
Dwarf_Attribute attrib = get_attr(DW_AT_location);
if(attrib != NULL)
{
Dwarf_Locdesc **llbuf = NULL;
Dwarf_Locdesc *locdesc = NULL;
Dwarf_Signed count = 0;
Dwarf_Error err = NULL;
DwarfDealloc dealloc(m_dbg);
size_t const nb_args = (info == NULL) ? 0 : info->size();
CHECK_DWERR(dwarf_loclist_n(attrib, &llbuf, &count, &err), err,
"cannot get location descriptions");
dealloc.add(llbuf, DW_DLA_LIST);
for(Dwarf_Signed idx = 0; idx < count; ++idx)
{
locdesc = llbuf[idx];
// handle deallocation too
dealloc.add(llbuf[idx], DW_DLA_LOCDESC);
dealloc.add(llbuf[idx]->ld_s, DW_DLA_LOC_BLOCK);
visit(*this, locdesc, funptr, cu_low_pc, offset_areas, info);
if(info != NULL && info->size() != nb_args)
{
// parameter has already been added, do not add it twice!
info = NULL;
}
}
}
}
