8 /* Set by the -securegc command line argument */
11 /* new objects are allocated here */
12 VM_C_API zone nursery;
14 /* GC is off during heap walking */
19 cell init_zone(zone *z, cell size, cell start)
22 z->start = z->here = start;
23 z->end = start + size;
27 void init_card_decks()
29 cell start = align(data->seg->start,deck_size);
30 allot_markers_offset = (cell)data->allot_markers - (start >> card_bits);
31 cards_offset = (cell)data->cards - (start >> card_bits);
32 decks_offset = (cell)data->decks - (start >> deck_bits);
35 data_heap *alloc_data_heap(cell gens,
40 young_size = align(young_size,deck_size);
41 aging_size = align(aging_size,deck_size);
42 tenured_size = align(tenured_size,deck_size);
44 data_heap *data = (data_heap *)safe_malloc(sizeof(data_heap));
45 data->young_size = young_size;
46 data->aging_size = aging_size;
47 data->tenured_size = tenured_size;
48 data->gen_count = gens;
51 if(data->gen_count == 2)
52 total_size = young_size + 2 * tenured_size;
53 else if(data->gen_count == 3)
54 total_size = young_size + 2 * aging_size + 2 * tenured_size;
57 fatal_error("Invalid number of generations",data->gen_count);
58 return NULL; /* can't happen */
61 total_size += deck_size;
63 data->seg = alloc_segment(total_size);
65 data->generations = (zone *)safe_malloc(sizeof(zone) * data->gen_count);
66 data->semispaces = (zone *)safe_malloc(sizeof(zone) * data->gen_count);
68 cell cards_size = total_size >> card_bits;
69 data->allot_markers = (cell *)safe_malloc(cards_size);
70 data->allot_markers_end = data->allot_markers + cards_size;
72 data->cards = (cell *)safe_malloc(cards_size);
73 data->cards_end = data->cards + cards_size;
75 cell decks_size = total_size >> deck_bits;
76 data->decks = (cell *)safe_malloc(decks_size);
77 data->decks_end = data->decks + decks_size;
79 cell alloter = align(data->seg->start,deck_size);
81 alloter = init_zone(&data->generations[data->tenured()],tenured_size,alloter);
82 alloter = init_zone(&data->semispaces[data->tenured()],tenured_size,alloter);
84 if(data->gen_count == 3)
86 alloter = init_zone(&data->generations[data->aging()],aging_size,alloter);
87 alloter = init_zone(&data->semispaces[data->aging()],aging_size,alloter);
90 if(data->gen_count >= 2)
92 alloter = init_zone(&data->generations[data->nursery()],young_size,alloter);
93 alloter = init_zone(&data->semispaces[data->nursery()],0,alloter);
96 if(data->seg->end - alloter > deck_size)
97 critical_error("Bug in alloc_data_heap",alloter);
102 data_heap *grow_data_heap(data_heap *data, cell requested_bytes)
104 cell new_tenured_size = (data->tenured_size * 2) + requested_bytes;
106 return alloc_data_heap(data->gen_count,
112 void dealloc_data_heap(data_heap *data)
114 dealloc_segment(data->seg);
115 free(data->generations);
116 free(data->semispaces);
117 free(data->allot_markers);
123 void clear_cards(cell from, cell to)
125 /* NOTE: reverse order due to heap layout. */
126 card *first_card = addr_to_card(data->generations[to].start);
127 card *last_card = addr_to_card(data->generations[from].end);
128 memset(first_card,0,last_card - first_card);
131 void clear_decks(cell from, cell to)
133 /* NOTE: reverse order due to heap layout. */
134 card_deck *first_deck = addr_to_deck(data->generations[to].start);
135 card_deck *last_deck = addr_to_deck(data->generations[from].end);
136 memset(first_deck,0,last_deck - first_deck);
139 void clear_allot_markers(cell from, cell to)
141 /* NOTE: reverse order due to heap layout. */
142 card *first_card = addr_to_allot_marker((object *)data->generations[to].start);
143 card *last_card = addr_to_allot_marker((object *)data->generations[from].end);
144 memset(first_card,invalid_allot_marker,last_card - first_card);
147 void reset_generation(cell i)
149 zone *z = (i == data->nursery() ? &nursery : &data->generations[i]);
153 memset((void*)z->start,69,z->size);
156 /* After garbage collection, any generations which are now empty need to have
157 their allocation pointers and cards reset. */
158 void reset_generations(cell from, cell to)
161 for(i = from; i <= to; i++)
164 clear_cards(from,to);
165 clear_decks(from,to);
166 clear_allot_markers(from,to);
169 void set_data_heap(data_heap *data_)
172 nursery = data->generations[data->nursery()];
174 clear_cards(data->nursery(),data->tenured());
175 clear_decks(data->nursery(),data->tenured());
176 clear_allot_markers(data->nursery(),data->tenured());
179 void init_data_heap(cell gens,
185 set_data_heap(alloc_data_heap(gens,young_size,aging_size,tenured_size));
186 secure_gc = secure_gc_;
190 /* Size of the object pointed to by a tagged pointer */
191 cell object_size(cell tagged)
193 if(immediate_p(tagged))
196 return untagged_object_size(untag<object>(tagged));
199 /* Size of the object pointed to by an untagged pointer */
200 cell untagged_object_size(object *pointer)
202 return align8(unaligned_object_size(pointer));
205 /* Size of the data area of an object pointed to by an untagged pointer */
206 cell unaligned_object_size(object *pointer)
208 switch(pointer->h.hi_tag())
211 return array_size((array*)pointer);
213 return array_size((bignum*)pointer);
214 case BYTE_ARRAY_TYPE:
215 return array_size((byte_array*)pointer);
217 return string_size(string_capacity((string*)pointer));
219 return tuple_size(untag<tuple_layout>(((tuple *)pointer)->layout));
221 return sizeof(quotation);
225 return sizeof(boxed_float);
229 return sizeof(alien);
231 return sizeof(wrapper);
233 return callstack_size(untag_fixnum(((callstack *)pointer)->length));
235 critical_error("Invalid header",(cell)pointer);
236 return 0; /* can't happen */
242 box_unsigned_cell(object_size(dpop()));
245 /* The number of cells from the start of the object which should be scanned by
246 the GC. Some types have a binary payload at the end (string, word, DLL) which
248 cell binary_payload_start(object *pointer)
250 switch(pointer->h.hi_tag())
252 /* these objects do not refer to other objects at all */
254 case BYTE_ARRAY_TYPE:
258 /* these objects have some binary data at the end */
260 return sizeof(word) - sizeof(cell) * 3;
262 return sizeof(cell) * 3;
264 return sizeof(cell) * 2;
266 return sizeof(quotation) - sizeof(cell) * 2;
268 return sizeof(string);
269 /* everything else consists entirely of pointers */
271 return array_size<array>(array_capacity((array*)pointer));
273 return tuple_size(untag<tuple_layout>(((tuple *)pointer)->layout));
275 return sizeof(wrapper);
277 critical_error("Invalid header",(cell)pointer);
278 return 0; /* can't happen */
282 /* Push memory usage statistics in data heap */
285 dpush(tag_fixnum((data->cards_end - data->cards) >> 10));
286 dpush(tag_fixnum((data->decks_end - data->decks) >> 10));
291 for(gen = 0; gen < data->gen_count; gen++)
293 zone *z = (gen == data->nursery() ? &nursery : &data->generations[gen]);
294 a.add(tag_fixnum((z->end - z->here) >> 10));
295 a.add(tag_fixnum((z->size) >> 10));
299 dpush(a.elements.value());
302 /* A heap walk allows useful things to be done, like finding all
303 references to an object for debugging purposes. */
306 /* Disables GC and activates next-object ( -- obj ) primitive */
309 heap_scan_ptr = data->generations[data->tenured()].start;
318 PRIMITIVE(begin_scan)
326 general_error(ERROR_HEAP_SCAN,F,F,NULL);
328 if(heap_scan_ptr >= data->generations[data->tenured()].here)
331 object *obj = (object *)heap_scan_ptr;
332 heap_scan_ptr += untagged_object_size(obj);
333 return tag_dynamic(obj);
336 /* Push object at heap scan cursor and advance; pushes f when done */
337 PRIMITIVE(next_object)
339 dpush(next_object());
348 template<typename T> void each_object(T &functor)
352 while((obj = next_object()) != F)
353 functor(tagged<object>(obj));
360 struct word_counter {
362 word_counter() : count(0) {}
363 void operator()(tagged<object> obj) { if(obj.type_p(WORD_TYPE)) count++; }
366 struct word_accumulator {
367 growable_array words;
368 word_accumulator(int count) : words(count) {}
369 void operator()(tagged<object> obj) { if(obj.type_p(WORD_TYPE)) words.add(obj.value()); }
374 cell find_all_words()
376 word_counter counter;
377 each_object(counter);
378 word_accumulator accum(counter.count);
381 return accum.words.elements.value();