vm/code_heap.cpp

   1 #include "master.hpp"
   2
   3 namespace factor
   4 {
   5
   6 code_heap::code_heap(cell size)
   7 {
   8         if(size > (1L << (sizeof(cell) * 8 - 6))) fatal_error("Heap too large",size);
   9         seg = new segment(align_page(size),true);
  10         if(!seg) fatal_error("Out of memory in heap allocator",size);
  11         allocator = new free_list_allocator<code_block>(size,seg->start);
  12 }
  13
  14 code_heap::~code_heap()
  15 {
  16         delete allocator;
  17         allocator = NULL;
  18         delete seg;
  19         seg = NULL;
  20 }
  21
  22 void code_heap::write_barrier(code_block *compiled)
  23 {
  24         points_to_nursery.insert(compiled);
  25         points_to_aging.insert(compiled);
  26 }
  27
  28 void code_heap::clear_remembered_set()
  29 {
  30         points_to_nursery.clear();
  31         points_to_aging.clear();
  32 }
  33
  34 bool code_heap::needs_fixup_p(code_block *compiled)
  35 {
  36         return needs_fixup.count(compiled) > 0;
  37 }
  38
  39 bool code_heap::marked_p(code_block *compiled)
  40 {
  41         return allocator->state.marked_p(compiled);
  42 }
  43
  44 void code_heap::set_marked_p(code_block *compiled)
  45 {
  46         allocator->state.set_marked_p(compiled);
  47 }
  48
  49 void code_heap::clear_mark_bits()
  50 {
  51         allocator->state.clear_mark_bits();
  52 }
  53
  54 void code_heap::code_heap_free(code_block *compiled)
  55 {
  56         points_to_nursery.erase(compiled);
  57         points_to_aging.erase(compiled);
  58         needs_fixup.erase(compiled);
  59         allocator->free(compiled);
  60 }
  61
  62 /* Allocate a code heap during startup */
  63 void factor_vm::init_code_heap(cell size)
  64 {
  65         code = new code_heap(size);
  66 }
  67
  68 bool factor_vm::in_code_heap_p(cell ptr)
  69 {
  70         return (ptr >= code->seg->start && ptr <= code->seg->end);
  71 }
  72
  73 /* Compile a word definition with the non-optimizing compiler. Allocates memory */
  74 void factor_vm::jit_compile_word(cell word_, cell def_, bool relocate)
  75 {
  76         data_root<word> word(word_,this);
  77         data_root<quotation> def(def_,this);
  78
  79         jit_compile(def.value(),relocate);
  80
  81         word->code = def->code;
  82
  83         if(to_boolean(word->pic_def)) jit_compile(word->pic_def,relocate);
  84         if(to_boolean(word->pic_tail_def)) jit_compile(word->pic_tail_def,relocate);
  85 }
  86
  87 struct word_updater {
  88         factor_vm *parent;
  89
  90         explicit word_updater(factor_vm *parent_) : parent(parent_) {}
  91
  92         void operator()(code_block *compiled, cell size)
  93         {
  94                 parent->update_word_references(compiled);
  95         }
  96 };
  97
  98 /* Update pointers to words referenced from all code blocks. Only after
  99 defining a new word. */
 100 void factor_vm::update_code_heap_words()
 101 {
 102         word_updater updater(this);
 103         iterate_code_heap(updater);
 104 }
 105
 106 /* After a full GC that did not grow the heap, we have to update references
 107 to literals and other words. */
 108 struct word_and_literal_code_heap_updater {
 109         factor_vm *parent;
 110
 111         explicit word_and_literal_code_heap_updater(factor_vm *parent_) : parent(parent_) {}
 112
 113         void operator()(code_block *block, cell size)
 114         {
 115                 parent->update_code_block_words_and_literals(block);
 116         }
 117 };
 118
 119 void factor_vm::update_code_heap_words_and_literals()
 120 {
 121         current_gc->event->started_code_sweep();
 122         word_and_literal_code_heap_updater updater(this);
 123         code->allocator->sweep(updater);
 124         current_gc->event->ended_code_sweep();
 125 }
 126
 127 /* After growing the heap, we have to perform a full relocation to update
 128 references to card and deck arrays. */
 129 struct code_heap_relocator {
 130         factor_vm *parent;
 131
 132         explicit code_heap_relocator(factor_vm *parent_) : parent(parent_) {}
 133
 134         void operator()(code_block *block, cell size)
 135         {
 136                 parent->relocate_code_block(block);
 137         }
 138 };
 139
 140 void factor_vm::relocate_code_heap()
 141 {
 142         code_heap_relocator relocator(this);
 143         code->allocator->sweep(relocator);
 144 }
 145
 146 void factor_vm::primitive_modify_code_heap()
 147 {
 148         data_root<array> alist(dpop(),this);
 149
 150         cell count = array_capacity(alist.untagged());
 151
 152         if(count == 0)
 153                 return;
 154
 155         cell i;
 156         for(i = 0; i < count; i++)
 157         {
 158                 data_root<array> pair(array_nth(alist.untagged(),i),this);
 159
 160                 data_root<word> word(array_nth(pair.untagged(),0),this);
 161                 data_root<object> data(array_nth(pair.untagged(),1),this);
 162
 163                 switch(data.type())
 164                 {
 165                 case QUOTATION_TYPE:
 166                         jit_compile_word(word.value(),data.value(),false);
 167                         break;
 168                 case ARRAY_TYPE:
 169                         {
 170                                 array *compiled_data = data.as<array>().untagged();
 171                                 cell owner = array_nth(compiled_data,0);
 172                                 cell literals = array_nth(compiled_data,1);
 173                                 cell relocation = array_nth(compiled_data,2);
 174                                 cell labels = array_nth(compiled_data,3);
 175                                 cell code = array_nth(compiled_data,4);
 176
 177                                 code_block *compiled = add_code_block(
 178                                         code_block_optimized,
 179                                         code,
 180                                         labels,
 181                                         owner,
 182                                         relocation,
 183                                         literals);
 184
 185                                 word->code = compiled;
 186                         }
 187                         break;
 188                 default:
 189                         critical_error("Expected a quotation or an array",data.value());
 190                         break;
 191                 }
 192
 193                 update_word_xt(word.untagged());
 194         }
 195
 196         update_code_heap_words();
 197 }
 198
 199 code_heap_room factor_vm::code_room()
 200 {
 201         code_heap_room room;
 202
 203         room.size             = code->allocator->size;
 204         room.occupied_space   = code->allocator->occupied_space();
 205         room.total_free       = code->allocator->free_space();
 206         room.contiguous_free  = code->allocator->largest_free_block();
 207         room.free_block_count = code->allocator->free_block_count();
 208
 209         return room;
 210 }
 211
 212 void factor_vm::primitive_code_room()
 213 {
 214         code_heap_room room = code_room();
 215         dpush(tag<byte_array>(byte_array_from_value(&room)));
 216 }
 217
 218 struct stack_trace_stripper {
 219         explicit stack_trace_stripper() {}
 220
 221         void operator()(code_block *compiled, cell size)
 222         {
 223                 compiled->owner = false_object;
 224         }
 225 };
 226
 227 void factor_vm::primitive_strip_stack_traces()
 228 {
 229         stack_trace_stripper stripper;
 230         iterate_code_heap(stripper);
 231 }
 232
 233 }