5 /* After a sweep, invalidate any code heap roots which are not marked,
6 so that if a block makes a tail call to a generic word, and the PIC
7 compiler triggers a GC, and the caller block gets GCd as a result,
8 the PIC code won't try to overwrite the call site */
9 void factor_vm::update_code_roots_for_sweep() {
10 std::vector<code_root*>::const_iterator iter = code_roots.begin();
11 std::vector<code_root*>::const_iterator end = code_roots.end();
13 mark_bits* state = &code->allocator->state;
15 for (; iter < end; iter++) {
16 code_root* root = *iter;
17 cell block = root->value & (~data_alignment - 1);
18 if (root->valid && !state->marked_p(block))
23 void factor_vm::collect_mark_impl(bool trace_contexts_p) {
24 gc_workhorse<tenured_space, full_policy>
25 workhorse(this, this->data->tenured, full_policy(this));
27 slot_visitor<gc_workhorse<tenured_space, full_policy> >
28 visitor(this, workhorse);
32 code->allocator->state.clear_mark_bits();
33 data->tenured->state.clear_mark_bits();
35 visitor.visit_roots();
36 if (trace_contexts_p) {
37 visitor.visit_contexts();
38 visitor.visit_context_code_blocks();
39 visitor.visit_uninitialized_code_blocks();
42 while (!mark_stack.empty()) {
43 cell ptr = mark_stack.back();
44 mark_stack.pop_back();
47 code_block* compiled = (code_block*)(ptr - 1);
48 visitor.visit_code_block_objects(compiled);
49 visitor.visit_embedded_literals(compiled);
50 visitor.visit_embedded_code_pointers(compiled);
52 object* obj = (object*)ptr;
53 visitor.visit_slots(obj);
54 if (obj->type() == ALIEN_TYPE)
55 ((alien*)obj)->update_address();
56 visitor.visit_object_code_block(obj);
59 data->reset_tenured();
61 data->reset_nursery();
62 code->clear_remembered_set();
65 void factor_vm::collect_sweep_impl() {
66 gc_event* event = current_gc->event;
69 event->started_data_sweep();
70 data->tenured->sweep();
72 event->ended_data_sweep();
74 update_code_roots_for_sweep();
77 event->started_code_sweep();
80 event->ended_code_sweep();
83 void factor_vm::collect_full(bool trace_contexts_p) {
84 collect_mark_impl(trace_contexts_p);
87 if (data->low_memory_p()) {
88 /* Full GC did not free up enough memory. Grow the heap. */
89 set_current_gc_op(collect_growing_heap_op);
90 collect_growing_heap(0, trace_contexts_p);
91 } else if (data->high_fragmentation_p()) {
92 /* Enough free memory, but it is not contiguous. Perform a
94 set_current_gc_op(collect_compact_op);
95 collect_compact_impl(trace_contexts_p);