#include "factor.h"

void dump_generations(void)
{
	int i;
	for(i = 0; i < GC_GENERATIONS; i++)
	{
		fprintf(stderr,"Generation %d: base=%d, size=%d, here=%d\n",
			i,
			generations[i].base,
			generations[i].limit - generations[i].base,
			generations[i].here);
	}

	fprintf(stderr,"Semispace: base=%d, size=%d, here=%d\n",
		prior.base,
		prior.limit - prior.base,
		prior.here);

	fprintf(stderr,"Cards: base=%d, size=%d\n",cards,cards_end - cards);
}

CELL init_zone(ZONE *z, CELL size, CELL base)
{
	z->base = z->here = base;
	z->limit = z->base + size;
	z->alarm = z->base + (size * 3) / 4;
	return z->limit;
}

/* input parameters must be 8 byte aligned */
void init_arena(CELL young_size, CELL aging_size)
{
	CELL total_size = (GC_GENERATIONS - 1) * young_size + 2 * aging_size;
	CELL cards_size = total_size / CARD_SIZE;

	heap_start = (CELL)alloc_guarded(total_size);
	cards = alloc_guarded(cards_size);
	cards_end = cards + cards_size;
	clear_cards();

	int i;
	CELL alloter = heap_start;

	if(heap_start == 0)
		fatal_error("Cannot allocate data heap",total_size);

	alloter = init_zone(&generations[TENURED],aging_size,alloter);
	alloter = init_zone(&prior,aging_size,alloter);

	for(i = 0; i < GC_GENERATIONS - 1; i++)
		alloter = init_zone(&generations[i],young_size,alloter);

	if(alloter != heap_start + total_size)
		fatal_error("Oops",alloter);

	allot_profiling = false;
	gc_in_progress = false;
	heap_scan = false;
	gc_time = 0;
	
	dump_generations();
}

void allot_profile_step(CELL a)
{
	CELL depth = (cs - cs_bot) / CELLS;
	int i;
	CELL obj;

	if(gc_in_progress)
		return;

	for(i = profile_depth; i < depth; i++)
	{
		obj = get(cs_bot + i * CELLS);
		if(type_of(obj) == WORD_TYPE)
			untag_word(obj)->allot_count += a;
	}

	if(in_zone(&prior,executing))
		critical_error("executing in prior zone",executing);
	untag_word_fast(executing)->allot_count += a;
}

void flip_zones()
{
	ZONE z = active;
	active = prior;
	prior = z;
	active.here = active.base;
}

void primitive_room(void)
{
	box_signed_cell(compiling.limit - compiling.here);
	box_signed_cell(compiling.limit - compiling.base);
	box_signed_cell(active.limit - active.here);
	box_signed_cell(active.limit - active.base);
}

void primitive_allot_profiling(void)
{
	CELL d = dpop();
	if(d == F)
		allot_profiling = false;
	else
	{
		allot_profiling = true;
		profile_depth = to_fixnum(d);
	}
}

void primitive_address(void)
{
	drepl(tag_bignum(s48_ulong_to_bignum(dpeek())));
}

void primitive_size(void)
{
	drepl(tag_fixnum(object_size(dpeek())));
}

void primitive_begin_scan(void)
{
	primitive_gc();
	heap_scan_ptr = active.base;
	heap_scan_end = active.here;
	heap_scan = true;
}

void primitive_next_object(void)
{
	CELL value = get(heap_scan_ptr);
	CELL obj = heap_scan_ptr;
	CELL size, type;

	if(!heap_scan)
		general_error(ERROR_HEAP_SCAN,F);

	if(heap_scan_ptr >= heap_scan_end)
	{
		dpush(F);
		return;
	}
	
	if(headerp(value))
	{
		size = align8(untagged_object_size(heap_scan_ptr));
		type = untag_header(value);
	}
	else
	{
		size = CELLS * 2;
		type = CONS_TYPE;
	}

	heap_scan_ptr += size;

	if(type < HEADER_TYPE)
		dpush(RETAG(obj,type));
	else
		dpush(RETAG(obj,OBJECT_TYPE));
}

void primitive_end_scan(void)
{
	heap_scan = false;
}