factor/vm/debug.cpp

#include "master.hpp"

namespace factor
{

std::ostream &operator<<(std::ostream &out, const string *str)
{
	for(cell i = 0; i < string_capacity(str); i++)
		out << (char)str->data()[i];
	return out;
}

void factor_vm::print_word(word *word, cell nesting)
{
	if(tagged<object>(word->vocabulary).type_p(STRING_TYPE))
		std::cout << untag<string>(word->vocabulary) << ":";

	if(tagged<object>(word->name).type_p(STRING_TYPE))
		std::cout << untag<string>(word->name);
	else
	{
		std::cout << "#<not a string: ";
		print_nested_obj(word->name,nesting);
		std::cout << ">";
	}
}

void factor_vm::print_factor_string(string *str)
{
	std::cout << '"' << str << '"';
}

void factor_vm::print_array(array *array, cell nesting)
{
	cell length = array_capacity(array);
	cell i;
	bool trimmed;

	if(length > 10 && !full_output)
	{
		trimmed = true;
		length = 10;
	}
	else
		trimmed = false;

	for(i = 0; i < length; i++)
	{
		std::cout << " ";
		print_nested_obj(array_nth(array,i),nesting);
	}

	if(trimmed)
		std::cout << "...";
}

void factor_vm::print_alien(alien *alien, cell nesting)
{
	if (to_boolean(alien->expired))
		std::cout << "#<expired alien>";
	else if (to_boolean(alien->base))
	{
		std::cout << "#<displaced alien " << alien->displacement << "+";
		print_nested_obj(alien->base, nesting);
		std::cout << ">";
	}
	else
	{
		std::cout << "#<alien " << (void*)alien->address << ">";
	}
}

void factor_vm::print_byte_array(byte_array *array, cell nesting)
{
	cell length = array->capacity;
	cell i;
	bool trimmed;
	unsigned char *data = array->data<unsigned char>();

	if(length > 16 && !full_output)
	{
		trimmed = true;
		length = 16;
	}
	else
		trimmed = false;

	for(i = 0; i < length; i++)
	{
		std::cout << " " << (unsigned)data[i];
	}

	if(trimmed)
		std::cout << "...";
}

void factor_vm::print_tuple(tuple *tuple, cell nesting)
{
	tuple_layout *layout = untag<tuple_layout>(tuple->layout);
	cell length = to_fixnum(layout->size);

	std::cout << " ";
	print_nested_obj(layout->klass,nesting);

	bool trimmed;
	if(length > 10 && !full_output)
	{
		trimmed = true;
		length = 10;
	}
	else
		trimmed = false;

	for(cell i = 0; i < length; i++)
	{
		std::cout << " ";
		print_nested_obj(tuple->data()[i],nesting);
	}

	if(trimmed)
		std::cout << "...";
}

void factor_vm::print_nested_obj(cell obj, fixnum nesting)
{
	if(nesting <= 0 && !full_output)
	{
		std::cout << " ... ";
		return;
	}

	quotation *quot;

	switch(tagged<object>(obj).type())
	{
	case FIXNUM_TYPE:
		std::cout << untag_fixnum(obj);
		break;
	case FLOAT_TYPE:
		std::cout << untag_float(obj);
		break;
	case WORD_TYPE:
		print_word(untag<word>(obj),nesting - 1);
		break;
	case STRING_TYPE:
		print_factor_string(untag<string>(obj));
		break;
	case F_TYPE:
		std::cout << "f";
		break;
	case TUPLE_TYPE:
		std::cout << "T{";
		print_tuple(untag<tuple>(obj),nesting - 1);
		std::cout << " }";
		break;
	case WRAPPER_TYPE:
		std::cout << "W{ ";
		print_nested_obj(untag<wrapper>(obj)->object,nesting - 1);
		std::cout << " }";
		break;
	case BYTE_ARRAY_TYPE:
		std::cout << "B{";
		print_byte_array(untag<byte_array>(obj),nesting - 1);
		std::cout << " }";
		break;
	case ARRAY_TYPE:
		std::cout << "{";
		print_array(untag<array>(obj),nesting - 1);
		std::cout << " }";
		break;
	case QUOTATION_TYPE:
		std::cout << "[";
		quot = untag<quotation>(obj);
		print_array(untag<array>(quot->array),nesting - 1);
		std::cout << " ]";
		break;
	case ALIEN_TYPE:
		print_alien(untag<alien>(obj), nesting - 1);
		break;
	default:
		std::cout << "#<" << type_name(tagged<object>(obj).type()) << " @ ";
		std::cout << (void*)obj << ">";
		break;
	}
	std::cout << std::flush;
}

void factor_vm::print_obj(cell obj)
{
	print_nested_obj(obj,10);
}

void factor_vm::print_objects(cell *start, cell *end)
{
	for(; start <= end; start++)
	{
		print_obj(*start);
		std::cout << std::endl;
	}
}

void factor_vm::print_datastack()
{
	std::cout << "==== DATA STACK:" << std::endl;
	if (ctx)
		print_objects((cell *)ctx->datastack_seg->start,(cell *)ctx->datastack);
	else
		std::cout << "*** Context not initialized" << std::endl;
}

void factor_vm::print_retainstack()
{
	std::cout << "==== RETAIN STACK:" << std::endl;
	if (ctx)
		print_objects((cell *)ctx->retainstack_seg->start,(cell *)ctx->retainstack);
	else
		std::cout << "*** Context not initialized" << std::endl;
}

struct stack_frame_printer {
	factor_vm *parent;

	explicit stack_frame_printer(factor_vm *parent_) : parent(parent_) {}
	void operator()(void *frame_top, cell frame_size, code_block *owner, void *addr)
	{
		std::cout << std::endl;
		std::cout << "frame: " << frame_top << " size " << frame_size << std::endl;
		std::cout << "executing: ";
		parent->print_obj(owner->owner);
		std::cout << std::endl;
		std::cout << "scan: ";
		parent->print_obj(owner->scan(parent, addr));
		std::cout << std::endl;
		std::cout << "word/quot addr: ";
		std::cout << std::hex << (cell)owner->owner << std::dec;
		std::cout << std::endl;
		std::cout << "word/quot xt: ";
		std::cout << std::hex << (cell)owner->entry_point() << std::dec;
		std::cout << std::endl;
		std::cout << "return address: ";
		std::cout << std::hex << (cell)addr << std::dec;
		std::cout << std::endl;
	}
};

void factor_vm::print_callstack()
{
	std::cout << "==== CALL STACK:" << std::endl;
	if (ctx)
	{
		stack_frame_printer printer(this);
		iterate_callstack(ctx,printer);
	}
	else
		std::cout << "*** Context not initialized" << std::endl;
}

void factor_vm::print_callstack_object(callstack *obj)
{
	stack_frame_printer printer(this);
	iterate_callstack_object(obj,printer);
}

struct padded_address {
	cell value;

	explicit padded_address(cell value_) : value(value_) {}
};

std::ostream &operator<<(std::ostream &out, const padded_address &value)
{
	char prev = out.fill('0');
	out.width(sizeof(cell) * 2);
	out << std::hex << value.value << std::dec;
	out.fill(prev);
	return out;
}

void factor_vm::dump_cell(cell x)
{
	std::cout << padded_address(x) << ": ";
	x = *(cell *)x;
	std::cout << padded_address(x) << " tag " << TAG(x) << std::endl;
}

void factor_vm::dump_memory(cell from, cell to)
{
	from = UNTAG(from);

	for(; from <= to; from += sizeof(cell))
		dump_cell(from);
}

template<typename Generation>
void factor_vm::dump_generation(const char *name, Generation *gen)
{
	std::cout << name << ": ";
	std::cout << "Start=" << gen->start;
	std::cout << ", size=" << gen->size;
	std::cout << ", end=" << gen->end;
	std::cout << std::endl;
}

void factor_vm::dump_generations()
{
	std::cout << std::hex;

	dump_generation("Nursery",&nursery);
	dump_generation("Aging",data->aging);
	dump_generation("Tenured",data->tenured);

	std::cout << "Cards:";
	std::cout << "base=" << (cell)data->cards << ", ";
	std::cout << "size=" << (cell)(data->cards_end - data->cards) << std::endl;

	std::cout << std::dec;
}

struct object_dumper {
	factor_vm *parent;
	cell type;

	explicit object_dumper(factor_vm *parent_, cell type_) :
		parent(parent_), type(type_) {}

	void operator()(object *obj)
	{
		if(type == TYPE_COUNT || obj->type() == type)
		{
			std::cout << padded_address((cell)obj) << " ";
			parent->print_nested_obj(tag_dynamic(obj),2);
			std::cout << std::endl;
		}
	}
};

void factor_vm::dump_objects(cell type)
{
	primitive_full_gc();
	object_dumper dumper(this,type);
	each_object(dumper);
}

struct find_data_reference_slot_visitor {
	cell look_for;
	object *obj;
	factor_vm *parent;

	explicit find_data_reference_slot_visitor(cell look_for_, object *obj_, factor_vm *parent_) :
		look_for(look_for_), obj(obj_), parent(parent_) { }

	void operator()(cell *scan)
	{
		if(look_for == *scan)
		{
			std::cout << padded_address((cell)obj) << " ";
			parent->print_nested_obj(tag_dynamic(obj),2);
			std::cout << std::endl;
		}
	}
};

struct dump_edges_slot_visitor {
	object *obj;
	factor_vm *parent;

	explicit dump_edges_slot_visitor(cell, object *obj_, factor_vm *parent_) :
		obj(obj_), parent(parent_) { }

	void operator()(cell *scan)
	{
		if (TAG(*scan) > F_TYPE)
			std::cout << (void*)tag_dynamic(obj) << " ==> " << (void*)*scan << std::endl;
	}
};

template <typename SlotVisitor>
struct data_reference_object_visitor {
	cell look_for;
	factor_vm *parent;

	explicit data_reference_object_visitor(cell look_for_, factor_vm *parent_) :
		look_for(look_for_), parent(parent_) {}

	void operator()(object *obj)
	{
		SlotVisitor visitor(look_for,obj,parent);
		obj->each_slot(visitor);
	}
};

void factor_vm::find_data_references(cell look_for)
{
	data_reference_object_visitor<find_data_reference_slot_visitor> visitor(look_for,this);
	each_object(visitor);
}

void factor_vm::dump_edges()
{
	data_reference_object_visitor<dump_edges_slot_visitor> visitor(0,this);
	each_object(visitor);
}

struct code_block_printer {
	factor_vm *parent;
	cell reloc_size, parameter_size;

	explicit code_block_printer(factor_vm *parent_) :
		parent(parent_), reloc_size(0), parameter_size(0) {}

	void operator()(code_block *scan, cell size)
	{
		const char *status;
		if(scan->free_p())
			status = "free";
		else
		{
			reloc_size += parent->object_size(scan->relocation);
			parameter_size += parent->object_size(scan->parameters);

			if(parent->code->marked_p(scan))
				status = "marked";
			else
				status = "allocated";

			std::cout << std::hex << (cell)scan << std::dec << " ";
			std::cout << std::hex << size << std::dec << " ";
			std::cout << status << " ";
			std::cout << "stack frame " << scan->stack_frame_size();
			std::cout << std::endl;
		}
	}
};

/* Dump all code blocks for debugging */
void factor_vm::dump_code_heap()
{
	code_block_printer printer(this);
	code->allocator->iterate(printer);
	std::cout << printer.reloc_size << " bytes used by relocation tables" << std::endl;
	std::cout << printer.parameter_size << " bytes used by parameter tables" << std::endl;
}

void factor_vm::factorbug_usage(bool advanced_p)
{
	std::cout << "Basic commands:" << std::endl;
#ifdef WINDOWS
	std::cout << "  q ^Z             -- quit Factor" << std::endl;
#else
	std::cout << "  q ^D             -- quit Factor" << std::endl;
#endif
	std::cout << "  c                -- continue executing Factor - NOT SAFE" << std::endl;
	std::cout << "  t                -- throw exception in Factor - NOT SAFE" << std::endl;
	std::cout << "  .s .r .c         -- print data, retain, call stacks" << std::endl;
	if (advanced_p)
	{
		std::cout << "  help             -- reprint this message" << std::endl;
		std::cout << "Advanced commands:" << std::endl;
		std::cout << "  e                -- dump environment" << std::endl;
		std::cout << "  d <addr> <count> -- dump memory" << std::endl;
		std::cout << "  u <addr>         -- dump object at tagged <addr>" << std::endl;
		std::cout << "  . <addr>         -- print object at tagged <addr>" << std::endl;
		std::cout << "  g                -- dump generations" << std::endl;
		std::cout << "  ds dr            -- dump data, retain stacks" << std::endl;
		std::cout << "  trim             -- toggle output trimming" << std::endl;
		std::cout << "  data             -- data heap dump" << std::endl;
		std::cout << "  words            -- words dump" << std::endl;
		std::cout << "  tuples           -- tuples dump" << std::endl;
		std::cout << "  edges            -- print all object-to-object references" << std::endl;
		std::cout << "  refs <addr>      -- find data heap references to object" << std::endl;
		std::cout << "  push <addr>      -- push object on data stack - NOT SAFE" << std::endl;
		std::cout << "  gc               -- trigger full GC - NOT SAFE" << std::endl;
		std::cout << "  compact-gc       -- trigger compacting GC - NOT SAFE" << std::endl;
		std::cout << "  code             -- code heap dump" << std::endl;
		std::cout << "  abort            -- call abort()" << std::endl;
		std::cout << "  breakpoint       -- trigger system breakpoint" << std::endl;
	}
	else
	{
		std::cout << "  help             -- full help, including advanced commands" << std::endl;
	}

	std::cout << std::endl;

}

static void exit_fep(factor_vm *vm)
{
	vm->unlock_console();
	vm->handle_ctrl_c();
	vm->fep_p = false;
}

void factor_vm::factorbug()
{
	if(fep_disabled)
	{
		std::cout << "Low level debugger disabled" << std::endl;
		exit(1);
	}

	if (sampling_profiler_p)
		end_sampling_profiler();

	fep_p = true;

	std::cout << "Starting low level debugger..." << std::endl;

	// Even though we've stopped the VM, the stdin_loop thread (see os-*.cpp)
	// that pumps the console is still running concurrently. We lock a mutex so
	// the thread will take a break and give us exclusive access to stdin.
	lock_console();
	ignore_ctrl_c();

	if (!fep_help_was_shown) {
		factorbug_usage(false);
		fep_help_was_shown = true;
	}
	bool seen_command = false;

	for(;;)
	{
		char cmd[1024];

		std::cout << "> " << std::flush;

		std::cin >> std::setw(1024) >> cmd >> std::setw(0); 
		if(!std::cin.good())
		{
			if(!seen_command)
			{
				/* If we exit with an EOF immediately, then
				dump stacks. This is useful for builder and
				other cases where Factor is run with stdin
				redirected to /dev/null */
				fep_disabled = true;

				print_datastack();
				print_retainstack();
				print_callstack();
			}

			exit(1);
		}

		seen_command = true;

		if(strcmp(cmd,"q") == 0)
			exit(1);
		if(strcmp(cmd,"d") == 0)
		{
			cell addr = read_cell_hex();
			if (std::cin.peek() == ' ')
				std::cin.ignore();

			if(!std::cin.good()) break;
			cell count = read_cell_hex();
			dump_memory(addr,addr+count);
		}
		else if(strcmp(cmd,"u") == 0)
		{
			cell addr = read_cell_hex();
			cell count = object_size(addr);
			dump_memory(addr,addr+count);
		}
		else if(strcmp(cmd,".") == 0)
		{
			cell addr = read_cell_hex();
			print_obj(addr);
			std::cout << std::endl;
		}
		else if(strcmp(cmd,"trim") == 0)
			full_output = !full_output;
		else if(strcmp(cmd,"ds") == 0)
			dump_memory(ctx->datastack_seg->start,ctx->datastack);
		else if(strcmp(cmd,"dr") == 0)
			dump_memory(ctx->retainstack_seg->start,ctx->retainstack);
		else if(strcmp(cmd,".s") == 0)
			print_datastack();
		else if(strcmp(cmd,".r") == 0)
			print_retainstack();
		else if(strcmp(cmd,".c") == 0)
			print_callstack();
		else if(strcmp(cmd,"e") == 0)
		{
			for(cell i = 0; i < special_object_count; i++)
				dump_cell((cell)&special_objects[i]);
		}
		else if(strcmp(cmd,"g") == 0)
			dump_generations();
		else if(strcmp(cmd,"c") == 0)
		{
			exit_fep(this);
			return;
		}
		else if(strcmp(cmd,"t") == 0)
		{
			exit_fep(this);
			general_error(ERROR_INTERRUPT,false_object,false_object);
			FACTOR_ASSERT(false);
		}
		else if(strcmp(cmd,"data") == 0)
			dump_objects(TYPE_COUNT);
		else if(strcmp(cmd,"edges") == 0)
			dump_edges();
		else if(strcmp(cmd,"refs") == 0)
		{
			cell addr = read_cell_hex();
			std::cout << "Data heap references:" << std::endl;
			find_data_references(addr);
			std::cout << std::endl;
		}
		else if(strcmp(cmd,"words") == 0)
			dump_objects(WORD_TYPE);
		else if(strcmp(cmd,"tuples") == 0)
			dump_objects(TUPLE_TYPE);
		else if(strcmp(cmd,"push") == 0)
		{
			cell addr = read_cell_hex();
			ctx->push(addr);
		}
		else if(strcmp(cmd,"code") == 0)
			dump_code_heap();
		else if(strcmp(cmd,"compact-gc") == 0)
			primitive_compact_gc();
		else if(strcmp(cmd,"gc") == 0)
			primitive_full_gc();
		else if(strcmp(cmd,"compact-gc") == 0)
			primitive_compact_gc();
		else if(strcmp(cmd,"help") == 0)
			factorbug_usage(true);
		else if(strcmp(cmd,"abort") == 0)
			abort();
		else if(strcmp(cmd,"breakpoint") == 0)
			breakpoint();
		else
			std::cout << "unknown command" << std::endl;
	}
}

void factor_vm::primitive_die()
{
	std::cout << "The die word was called by the library. Unless you called it yourself," << std::endl;
	std::cout << "you have triggered a bug in Factor. Please report." << std::endl;
	factorbug();
}

}