vm/full_collector.cpp

   1 #include "master.hpp"
   2
   3 namespace factor
   4 {
   5
   6 inline static code_block_visitor<code_workhorse> make_code_visitor(factor_vm *parent)
   7 {
   8         return code_block_visitor<code_workhorse>(parent,code_workhorse(parent));
   9 }
  10
  11 full_collector::full_collector(factor_vm *parent_) :
  12         collector<tenured_space,full_policy>(
  13                 parent_,
  14                 parent_->data->tenured,
  15                 full_policy(parent_)),
  16         code_visitor(make_code_visitor(parent_)) {}
  17
  18 void full_collector::trace_code_block(code_block *compiled)
  19 {
  20         data_visitor.visit_code_block_objects(compiled);
  21         data_visitor.visit_embedded_literals(compiled);
  22         code_visitor.visit_embedded_code_pointers(compiled);
  23 }
  24
  25 void full_collector::trace_context_code_blocks()
  26 {
  27         code_visitor.visit_context_code_blocks();
  28 }
  29
  30 void full_collector::trace_uninitialized_code_blocks()
  31 {
  32         code_visitor.visit_uninitialized_code_blocks();
  33 }
  34
  35 void full_collector::trace_object_code_block(object *obj)
  36 {
  37         code_visitor.visit_object_code_block(obj);
  38 }
  39
  40 /* After a sweep, invalidate any code heap roots which are not marked,
  41 so that if a block makes a tail call to a generic word, and the PIC
  42 compiler triggers a GC, and the caller block gets gets GCd as a result,
  43 the PIC code won't try to overwrite the call site */
  44 void factor_vm::update_code_roots_for_sweep()
  45 {
  46         std::vector<code_root *>::const_iterator iter = code_roots.begin();
  47         std::vector<code_root *>::const_iterator end = code_roots.end();
  48
  49         mark_bits<code_block> *state = &code->allocator->state;
  50
  51         for(; iter < end; iter++)
  52         {
  53                 code_root *root = *iter;
  54                 code_block *block = (code_block *)(root->value & (~data_alignment - 1));
  55                 if(root->valid && !state->marked_p(block))
  56                         root->valid = false;
  57         }
  58 }
  59
  60 void factor_vm::collect_mark_impl(bool trace_contexts_p)
  61 {
  62         full_collector collector(this);
  63
  64         mark_stack.clear();
  65
  66         code->clear_mark_bits();
  67         data->tenured->clear_mark_bits();
  68
  69         collector.trace_roots();
  70         if(trace_contexts_p)
  71         {
  72                 collector.trace_contexts();
  73                 collector.trace_context_code_blocks();
  74                 collector.trace_uninitialized_code_blocks();
  75         }
  76
  77         while(!mark_stack.empty())
  78         {
  79                 cell ptr = mark_stack.back();
  80                 mark_stack.pop_back();
  81
  82                 if(ptr & 1)
  83                 {
  84                         code_block *compiled = (code_block *)(ptr - 1);
  85                         collector.trace_code_block(compiled);
  86                 }
  87                 else
  88                 {
  89                         object *obj = (object *)ptr;
  90                         collector.trace_object(obj);
  91                         collector.trace_object_code_block(obj);
  92                 }
  93         }
  94
  95         data->reset_generation(data->tenured);
  96         data->reset_generation(data->aging);
  97         data->reset_generation(&nursery);
  98         code->clear_remembered_set();
  99 }
 100
 101 void factor_vm::collect_sweep_impl()
 102 {
 103         current_gc->event->started_data_sweep();
 104         data->tenured->sweep();
 105         current_gc->event->ended_data_sweep();
 106
 107         update_code_roots_for_sweep();
 108
 109         current_gc->event->started_code_sweep();
 110         code->allocator->sweep();
 111         current_gc->event->ended_code_sweep();
 112 }
 113
 114 void factor_vm::collect_full(bool trace_contexts_p)
 115 {
 116         collect_mark_impl(trace_contexts_p);
 117         collect_sweep_impl();
 118
 119         if(data->low_memory_p())
 120         {
 121                 current_gc->op = collect_growing_heap_op;
 122                 current_gc->event->op = collect_growing_heap_op;
 123                 collect_growing_heap(0,trace_contexts_p);
 124         }
 125         else if(data->high_fragmentation_p())
 126         {
 127                 current_gc->op = collect_compact_op;
 128                 current_gc->event->op = collect_compact_op;
 129                 collect_compact_impl(trace_contexts_p);
 130         }
 131
 132         code->flush_icache();
 133 }
 134
 135 }