Dwarf_P_Die ElfWriter::addFunctionInfo(FunctionInfo* f, Dwarf_P_Die type) {
Dwarf_Error error = 0;
/* top level DIE for each function */
Dwarf_P_Die func = dwarf_new_die(m_dwarfProducer,
DW_TAG_subprogram, nullptr, nullptr, nullptr, nullptr, &error);
if (reinterpret_cast<Dwarf_Addr>(func) == DW_DLV_BADADDR) {
logError("unable to create child DIE");
return nullptr;
}
Dwarf_Signed file;
FileDB::iterator it = m_fileDB.find(f->file);
/* if this function is from an unseen file, register file name
* and get index to file name */
if (it == m_fileDB.end()) {
file = dwarf_add_file_decl(m_dwarfProducer,
(char *)f->file, 0, 0, 1000, &error);
if (file == DW_DLV_NOCOUNT) {
logError("unable to add file declaration");
return nullptr;
}
m_fileDB[f->file] = file;
} else {
file = it->second;
}
/* add function name attribute to function DIE */
Dwarf_P_Attribute at;
at = dwarf_add_AT_name(func, (char *)f->name.c_str(), &error);
if (reinterpret_cast<Dwarf_Addr>(at) == DW_DLV_BADADDR) {
logError("unable to add name attribute to function");
return nullptr;
}
/* Add lower PC bound to function DIE */
at = dwarf_add_AT_targ_address(m_dwarfProducer, func, DW_AT_low_pc,
reinterpret_cast<Dwarf_Unsigned>(f->range.begin()), 0, &error);
if (reinterpret_cast<Dwarf_Addr>(at) == DW_DLV_BADADDR) {
logError("unable to add low_pc attribute to function");
return nullptr;
}
/* add upper PC bound to function DIE */
at = dwarf_add_AT_targ_address(m_dwarfProducer, func, DW_AT_high_pc,
reinterpret_cast<Dwarf_Unsigned>(f->range.end()), 0, &error);
if (reinterpret_cast<Dwarf_Addr>(at) == DW_DLV_BADADDR) {
logError("unable to add high_pc attribute to function");
return nullptr;
}
/* register line number information for function:
* 1. register start address */
Dwarf_Unsigned u;
u = dwarf_lne_set_address(m_dwarfProducer,
reinterpret_cast<Dwarf_Addr>(f->range.begin()), 0, &error);
if (u != 0) {
logError("unable to set line start address");
return nullptr;
}
/* 2. register line number info for each tracelet in function */
std::vector<LineEntry>::iterator it2;
for (it2 = f->m_lineTable.begin(); it2 != f->m_lineTable.end(); it2++) {
u = dwarf_add_line_entry(m_dwarfProducer,
file, reinterpret_cast<Dwarf_Addr>(it2->range.begin()), it2->lineNumber,
0, 1, 0, &error);
if (u != 0) {
logError("unable to add line entry");
return nullptr;
}
TRACE(1, "elfwriter tracelet: %s %p %p\n",
m_filename.c_str(), it2->range.begin(), it2->range.end());
}
/* 3. register end address of function */
u = dwarf_lne_end_sequence(m_dwarfProducer,
reinterpret_cast<Dwarf_Addr>(f->range.end()), &error);
if (u != 0) {
logError("unable to set line end address");
return nullptr;
}
/* 4. register frame base of function */
Dwarf_P_Expr locExpr = dwarf_new_expr(m_dwarfProducer, &error);
if (locExpr == nullptr) {
logError("unable to create new location expression");
return nullptr;
}
u = dwarf_add_expr_gen(locExpr, DW_OP_call_frame_cfa, 0, 0, &error);
if (u == DW_DLV_NOCOUNT) {
logError("unable to add subexpression to location expression");
return nullptr;
}
u = dwarf_add_expr_gen(locExpr, DW_OP_const1u, CFA_OFFSET, 0, &error);
if (u == DW_DLV_NOCOUNT) {
logError("unable to add subexpression to location expression");
return nullptr;
}
u = dwarf_add_expr_gen(locExpr, DW_OP_minus, 0, 0, &error);
if (u == DW_DLV_NOCOUNT) {
logError("unable to add subexpression to location expression");
return nullptr;
}
Dwarf_P_Attribute frameBaseAttr = dwarf_add_AT_location_expr(m_dwarfProducer,
func, DW_AT_frame_base, locExpr, &error);
if (reinterpret_cast<Dwarf_Addr>(frameBaseAttr) == DW_DLV_BADADDR) {
logError("unable to add frame_base attribute");
return nullptr;
}
/* 5. register all the named locals of function */
Dwarf_P_Die lastLocal = nullptr;
int i = 1;
for (std::vector<std::string>::iterator it = f->m_namedLocals.begin();
it != f->m_namedLocals.end(); it++) {
Dwarf_P_Die localVar = dwarf_new_die(m_dwarfProducer,
DW_TAG_variable, nullptr, nullptr, nullptr, nullptr, &error);
if (reinterpret_cast<Dwarf_Addr>(localVar) == DW_DLV_BADADDR) {
logError("unable to create new DIE for local variable");
return nullptr;
}
/* Create location expression defined w.r.t DW_AT_frame_base */
Dwarf_P_Expr locExpr = dwarf_new_expr(m_dwarfProducer, &error);
if (locExpr == nullptr) {
logError("unable to create new location expression");
return nullptr;
}
u = dwarf_add_expr_gen(locExpr, DW_OP_fbreg,
-(i * sizeof(TypedValue)), 0, &error);
++i;
if (u == DW_DLV_NOCOUNT) {
logError("unable to add subexpression to location expression");
return nullptr;
}
Dwarf_P_Attribute locAttr = dwarf_add_AT_location_expr(m_dwarfProducer,
localVar, DW_AT_location, locExpr, &error);
if (reinterpret_cast<Dwarf_Addr>(locAttr) == DW_DLV_BADADDR) {
logError("unable to add location attribute to local variable");
return nullptr;
}
Dwarf_P_Attribute nameAttr = dwarf_add_AT_name(localVar, const_cast<char *>(it->data()), &error);
if (reinterpret_cast<Dwarf_Addr>(nameAttr) == DW_DLV_BADADDR) {
logError("unable to add name attribute to local variable");
return nullptr;
}
Dwarf_P_Attribute varTypeAttr = dwarf_add_AT_reference(m_dwarfProducer,
localVar, DW_AT_type, type, &error);
if (reinterpret_cast<Dwarf_Addr>(varTypeAttr) == DW_DLV_BADADDR) {
logError("unable to add type attribute to local variable DIE");
return nullptr;
}
Dwarf_P_Die res = 0;
if (lastLocal != nullptr) {
res = dwarf_die_link(localVar, nullptr, nullptr, lastLocal, nullptr, &error);
} else {
res = dwarf_die_link(localVar, func, nullptr, nullptr, nullptr, &error);
}
if (reinterpret_cast<Dwarf_Addr>(res) == DW_DLV_BADADDR) {
logError("unable to link die");
return nullptr;
}
lastLocal = localVar;
}
return func;
}
Dwarf_P_Die ElfWriter::addFunctionInfo(FunctionInfo* f) {
Dwarf_Error error = 0;
/* top level DIE for each function */
Dwarf_P_Die func = dwarf_new_die(m_dwarfProducer,
DW_TAG_subprogram, NULL, NULL, NULL, NULL, &error);
if (reinterpret_cast<Dwarf_Addr>(func) == DW_DLV_BADADDR) {
logError("unable to create child DIE");
return NULL;
}
Dwarf_Signed file;
FileDB::iterator it = m_fileDB.find(f->file);
/* if this function is from an unseen file, register file name
* and get index to file name */
if (it == m_fileDB.end()) {
file = dwarf_add_file_decl(m_dwarfProducer,
(char *)f->file, 0, 0, 1000, &error);
if (file == DW_DLV_NOCOUNT) {
logError("unable to add file declaration");
return NULL;
}
m_fileDB[f->file] = file;
} else {
file = it->second;
}
/* add function name attribute to function DIE */
Dwarf_P_Attribute at;
at = dwarf_add_AT_name(func, (char *)f->name.c_str(), &error);
if (reinterpret_cast<Dwarf_Addr>(at) == DW_DLV_BADADDR) {
logError("unable to add name attribute to function");
return NULL;
}
/* Add lower PC bound to function DIE */
at = dwarf_add_AT_targ_address(m_dwarfProducer, func, DW_AT_low_pc,
reinterpret_cast<Dwarf_Unsigned>(f->range.begin()), 0, &error);
if (reinterpret_cast<Dwarf_Addr>(at) == DW_DLV_BADADDR) {
logError("unable to add low_pc attribute to function");
return NULL;
}
/* add upper PC bound to function DIE */
at = dwarf_add_AT_targ_address(m_dwarfProducer, func, DW_AT_high_pc,
reinterpret_cast<Dwarf_Unsigned>(f->range.end()), 0, &error);
if (reinterpret_cast<Dwarf_Addr>(at) == DW_DLV_BADADDR) {
logError("unable to add high_pc attribute to function");
return NULL;
}
/* register line number information for function:
* 1. register start address */
Dwarf_Unsigned u;
u = dwarf_lne_set_address(m_dwarfProducer,
reinterpret_cast<Dwarf_Addr>(f->range.begin()), 0, &error);
if (u != 0) {
logError("unable to set line start address");
return NULL;
}
/* 2. register line number info for each tracelet in function */
std::vector<LineEntry>::iterator it2;
for (it2 = f->m_lineTable.begin(); it2 != f->m_lineTable.end(); it2++) {
u = dwarf_add_line_entry(m_dwarfProducer,
file, reinterpret_cast<Dwarf_Addr>(it2->range.begin()), it2->lineNumber,
0, 1, 0, &error);
if (u != 0) {
logError("unable to add line entry");
return NULL;
}
TRACE(1, "elfwriter tracelet: %s %p %p\n",
m_filename.c_str(), it2->range.begin(), it2->range.end());
}
/* 3. register end address of function */
u = dwarf_lne_end_sequence(m_dwarfProducer,
reinterpret_cast<Dwarf_Addr>(f->range.end()), &error);
if (u != 0) {
logError("unable to set line end address");
return NULL;
}
return func;
}