factor/vm/data_heap_checker.cpp

102 lines
2.5 KiB
C++

#include "master.hpp"
/* A tool to debug write barriers. Call check_data_heap() to ensure that all
cards that should be marked are actually marked. */
namespace factor
{
enum generation {
nursery_generation,
aging_generation,
tenured_generation
};
inline generation generation_of(factor_vm *parent, object *obj)
{
if(parent->data->nursery->contains_p(obj))
return nursery_generation;
else if(parent->data->aging->contains_p(obj))
return aging_generation;
else if(parent->data->tenured->contains_p(obj))
return tenured_generation;
else
{
critical_error("Bad object",(cell)obj);
return (generation)-1;
}
}
struct slot_checker {
factor_vm *parent;
object *obj;
generation gen;
explicit slot_checker(factor_vm *parent_, object *obj_, generation gen_) :
parent(parent_), obj(obj_), gen(gen_) {}
void check_write_barrier(cell *slot_ptr, generation target, char mask)
{
cell object_card_pointer = parent->cards_offset + ((cell)obj >> card_bits);
cell slot_card_pointer = parent->cards_offset + ((cell)slot_ptr >> card_bits);
char slot_card_value = *(char *)slot_card_pointer;
if((slot_card_value & mask) != mask)
{
printf("card not marked\n");
printf("source generation: %d\n",gen);
printf("target generation: %d\n",target);
printf("object: 0x%lx\n",(cell)obj);
printf("object type: %ld\n",obj->type());
printf("slot pointer: 0x%lx\n",(cell)slot_ptr);
printf("slot value: 0x%lx\n",*slot_ptr);
printf("card of object: 0x%lx\n",object_card_pointer);
printf("card of slot: 0x%lx\n",slot_card_pointer);
printf("\n");
parent->factorbug();
}
}
void operator()(cell *slot_ptr)
{
if(!immediate_p(*slot_ptr))
{
generation target = generation_of(parent,untag<object>(*slot_ptr));
switch(gen)
{
case nursery_generation:
break;
case aging_generation:
if(target == nursery_generation)
check_write_barrier(slot_ptr,target,card_points_to_nursery);
break;
case tenured_generation:
if(target == nursery_generation)
check_write_barrier(slot_ptr,target,card_points_to_nursery);
else if(target == aging_generation)
check_write_barrier(slot_ptr,target,card_points_to_aging);
break;
}
}
}
};
struct object_checker {
factor_vm *parent;
explicit object_checker(factor_vm *parent_) : parent(parent_) {}
void operator()(object *obj)
{
slot_checker checker(parent,obj,generation_of(parent,obj));
obj->each_slot(checker);
}
};
void factor_vm::check_data_heap()
{
object_checker checker(this);
each_object(checker);
}
}