/** Resolve a location expression */
Location resolve(
simgrid::dwarf::DwarfExpression const& expression,
simgrid::mc::ObjectInformation* object_info,
unw_cursor_t * c,
void *frame_pointer_address,
simgrid::mc::AddressSpace* address_space, int process_index)
{
simgrid::dwarf::ExpressionContext context;
context.frame_base = frame_pointer_address;
context.cursor = c;
context.address_space = address_space;
context.object_info = object_info;
context.process_index = process_index;
if (!expression.empty()
&& expression[0].atom >= DW_OP_reg0
&& expression[0].atom <= DW_OP_reg31) {
int dwarf_register = expression[0].atom - DW_OP_reg0;
xbt_assert(c,
"Missing frame context for register operation DW_OP_reg%i",
dwarf_register);
return Location(dwarf_register_to_libunwind(dwarf_register));
}
simgrid::dwarf::ExpressionStack stack;
simgrid::dwarf::execute(expression, context, stack);
return Location((void*) stack.top());
}
/** Whether the member is at a fixed offset from the base address */
bool has_offset_location() const
{
// Recognize the expression `DW_OP_plus_uconst(offset)`:
return location_expression.size() == 1 &&
location_expression[0].atom == DW_OP_plus_uconst;
}
inline
void execute(simgrid::dwarf::DwarfExpression const& expression,
ExpressionContext const& context, ExpressionStack& stack)
{
execute(expression.data(), expression.size(), context, stack);
}