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 > ((u64)1 << (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 code_heap constructor",size);
  11
  12         cell start = seg->start + getpagesize() + seh_area_size;
  13
  14         allocator = new free_list_allocator<code_block>(seg->end - start,start);
  15
  16         /* See os-windows-x86.64.cpp for seh_area usage */
  17         safepoint_page = (void *)seg->start;
  18         seh_area = (char *)seg->start + getpagesize();
  19 }
  20
  21 code_heap::~code_heap()
  22 {
  23         delete allocator;
  24         allocator = NULL;
  25         delete seg;
  26         seg = NULL;
  27 }
  28
  29 void code_heap::write_barrier(code_block *compiled)
  30 {
  31         points_to_nursery.insert(compiled);
  32         points_to_aging.insert(compiled);
  33 }
  34
  35 void code_heap::clear_remembered_set()
  36 {
  37         points_to_nursery.clear();
  38         points_to_aging.clear();
  39 }
  40
  41 bool code_heap::uninitialized_p(code_block *compiled)
  42 {
  43         return uninitialized_blocks.count(compiled) > 0;
  44 }
  45
  46 bool code_heap::marked_p(code_block *compiled)
  47 {
  48         return allocator->state.marked_p(compiled);
  49 }
  50
  51 void code_heap::set_marked_p(code_block *compiled)
  52 {
  53         allocator->state.set_marked_p(compiled);
  54 }
  55
  56 void code_heap::clear_mark_bits()
  57 {
  58         allocator->state.clear_mark_bits();
  59 }
  60
  61 void code_heap::free(code_block *compiled)
  62 {
  63         assert(!uninitialized_p(compiled));
  64         points_to_nursery.erase(compiled);
  65         points_to_aging.erase(compiled);
  66         allocator->free(compiled);
  67 }
  68
  69 void code_heap::flush_icache()
  70 {
  71         factor::flush_icache(seg->start,seg->size);
  72 }
  73
  74 struct address_finder {
  75         cell address;
  76         code_block *found_code_block;
  77
  78         address_finder(cell address)
  79                 : address(address), found_code_block(NULL) {}
  80
  81         void operator()(code_block *block, cell size)
  82         {
  83                 if ((cell)block->entry_point() <= address
  84                         && address - (cell)block->entry_point() < block->size())
  85                 {
  86                         assert(found_code_block == NULL);
  87                         found_code_block = block;
  88                 }
  89         }
  90 };
  91
  92 code_block *code_heap::code_block_for_address(cell address)
  93 {
  94         address_finder finder(address);
  95         allocator->iterate(finder);
  96         return finder.found_code_block;
  97 }
  98
  99 /* Allocate a code heap during startup */
 100 void factor_vm::init_code_heap(cell size)
 101 {
 102         code = new code_heap(size);
 103 }
 104
 105 struct word_updater {
 106         factor_vm *parent;
 107         bool reset_inline_caches;
 108
 109         word_updater(factor_vm *parent_, bool reset_inline_caches_) :
 110                 parent(parent_), reset_inline_caches(reset_inline_caches_) {}
 111
 112         void operator()(code_block *compiled, cell size)
 113         {
 114                 parent->update_word_references(compiled,reset_inline_caches);
 115         }
 116 };
 117
 118 /* Update pointers to words referenced from all code blocks.
 119 Only needed after redefining an existing word.
 120 If generic words were redefined, inline caches need to be reset. */
 121 void factor_vm::update_code_heap_words(bool reset_inline_caches)
 122 {
 123         word_updater updater(this,reset_inline_caches);
 124         each_code_block(updater);
 125 }
 126
 127 /* Fix up new words only.
 128 Fast path for compilation units that only define new words. */
 129 void factor_vm::initialize_code_blocks()
 130 {
 131         std::map<code_block *, cell>::const_iterator iter = code->uninitialized_blocks.begin();
 132         std::map<code_block *, cell>::const_iterator end = code->uninitialized_blocks.end();
 133
 134         for(; iter != end; iter++)
 135                 initialize_code_block(iter->first,iter->second);
 136
 137         code->uninitialized_blocks.clear();
 138 }
 139
 140 void factor_vm::primitive_modify_code_heap()
 141 {
 142         bool reset_inline_caches = to_boolean(ctx->pop());
 143         bool update_existing_words = to_boolean(ctx->pop());
 144         data_root<array> alist(ctx->pop(),this);
 145
 146         cell count = array_capacity(alist.untagged());
 147
 148         if(count == 0)
 149                 return;
 150
 151         for(cell i = 0; i < count; i++)
 152         {
 153                 data_root<array> pair(array_nth(alist.untagged(),i),this);
 154
 155                 data_root<word> word(array_nth(pair.untagged(),0),this);
 156                 data_root<object> data(array_nth(pair.untagged(),1),this);
 157
 158                 switch(data.type())
 159                 {
 160                 case QUOTATION_TYPE:
 161                         jit_compile_word(word.value(),data.value(),false);
 162                         break;
 163                 case ARRAY_TYPE:
 164                         {
 165                                 array *compiled_data = data.as<array>().untagged();
 166                                 cell parameters = array_nth(compiled_data,0);
 167                                 cell literals = array_nth(compiled_data,1);
 168                                 cell relocation = array_nth(compiled_data,2);
 169                                 cell labels = array_nth(compiled_data,3);
 170                                 cell code = array_nth(compiled_data,4);
 171
 172                                 code_block *compiled = add_code_block(
 173                                         code_block_optimized,
 174                                         code,
 175                                         labels,
 176                                         word.value(),
 177                                         relocation,
 178                                         parameters,
 179                                         literals);
 180
 181                                 word->entry_point = compiled->entry_point();
 182                         }
 183                         break;
 184                 default:
 185                         critical_error("Expected a quotation or an array",data.value());
 186                         break;
 187                 }
 188         }
 189
 190         if(update_existing_words)
 191                 update_code_heap_words(reset_inline_caches);
 192         else
 193                 initialize_code_blocks();
 194 }
 195
 196 code_heap_room factor_vm::code_room()
 197 {
 198         code_heap_room room;
 199
 200         room.size             = code->allocator->size;
 201         room.occupied_space   = code->allocator->occupied_space();
 202         room.total_free       = code->allocator->free_space();
 203         room.contiguous_free  = code->allocator->largest_free_block();
 204         room.free_block_count = code->allocator->free_block_count();
 205
 206         return room;
 207 }
 208
 209 void factor_vm::primitive_code_room()
 210 {
 211         code_heap_room room = code_room();
 212         ctx->push(tag<byte_array>(byte_array_from_value(&room)));
 213 }
 214
 215 struct stack_trace_stripper {
 216         explicit stack_trace_stripper() {}
 217
 218         void operator()(code_block *compiled, cell size)
 219         {
 220                 compiled->owner = false_object;
 221         }
 222 };
 223
 224 void factor_vm::primitive_strip_stack_traces()
 225 {
 226         stack_trace_stripper stripper;
 227         each_code_block(stripper);
 228 }
 229
 230 struct code_block_accumulator {
 231         std::vector<cell> objects;
 232
 233         void operator()(code_block *compiled, cell size)
 234         {
 235                 objects.push_back(compiled->owner);
 236                 objects.push_back(compiled->parameters);
 237                 objects.push_back(compiled->relocation);
 238
 239                 objects.push_back(tag_fixnum(compiled->type()));
 240                 objects.push_back(tag_fixnum(compiled->size()));
 241
 242                 /* Note: the entry point is always a multiple of the heap
 243                 alignment (16 bytes). We cannot allocate while iterating
 244                 through the code heap, so it is not possible to call
 245                 from_unsigned_cell() here. It is OK, however, to add it as
 246                 if it were a fixnum, and have library code shift it to the
 247                 left by 4. */
 248                 cell entry_point = (cell)compiled->entry_point();
 249                 assert((entry_point & (data_alignment - 1)) == 0);
 250                 assert((entry_point & TAG_MASK) == FIXNUM_TYPE);
 251                 objects.push_back(entry_point);
 252         }
 253 };
 254
 255 cell factor_vm::code_blocks()
 256 {
 257         code_block_accumulator accum;
 258         each_code_block(accum);
 259         return std_vector_to_array(accum.objects);
 260 }
 261
 262 void factor_vm::primitive_code_blocks()
 263 {
 264         ctx->push(code_blocks());
 265 }
 266
 267 }