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 /* Allocate a code heap during startup */
  75 void factor_vm::init_code_heap(cell size)
  76 {
  77         code = new code_heap(size);
  78 }
  79
  80 bool factor_vm::in_code_heap_p(cell ptr)
  81 {
  82         return (ptr >= code->seg->start && ptr <= code->seg->end);
  83 }
  84
  85 struct word_updater {
  86         factor_vm *parent;
  87         bool reset_inline_caches;
  88
  89         word_updater(factor_vm *parent_, bool reset_inline_caches_) :
  90                 parent(parent_), reset_inline_caches(reset_inline_caches_) {}
  91
  92         void operator()(code_block *compiled, cell size)
  93         {
  94                 parent->update_word_references(compiled,reset_inline_caches);
  95         }
  96 };
  97
  98 /* Update pointers to words referenced from all code blocks.
  99 Only needed after redefining an existing word.
 100 If generic words were redefined, inline caches need to be reset. */
 101 void factor_vm::update_code_heap_words(bool reset_inline_caches)
 102 {
 103         word_updater updater(this,reset_inline_caches);
 104         each_code_block(updater);
 105 }
 106
 107 /* Fix up new words only.
 108 Fast path for compilation units that only define new words. */
 109 void factor_vm::initialize_code_blocks()
 110 {
 111         std::map<code_block *, cell>::const_iterator iter = code->uninitialized_blocks.begin();
 112         std::map<code_block *, cell>::const_iterator end = code->uninitialized_blocks.end();
 113
 114         for(; iter != end; iter++)
 115                 initialize_code_block(iter->first,iter->second);
 116
 117         code->uninitialized_blocks.clear();
 118 }
 119
 120 void factor_vm::primitive_modify_code_heap()
 121 {
 122         bool reset_inline_caches = to_boolean(ctx->pop());
 123         bool update_existing_words = to_boolean(ctx->pop());
 124         data_root<array> alist(ctx->pop(),this);
 125
 126         cell count = array_capacity(alist.untagged());
 127
 128         if(count == 0)
 129                 return;
 130
 131         for(cell i = 0; i < count; i++)
 132         {
 133                 data_root<array> pair(array_nth(alist.untagged(),i),this);
 134
 135                 data_root<word> word(array_nth(pair.untagged(),0),this);
 136                 data_root<object> data(array_nth(pair.untagged(),1),this);
 137
 138                 switch(data.type())
 139                 {
 140                 case QUOTATION_TYPE:
 141                         jit_compile_word(word.value(),data.value(),false);
 142                         break;
 143                 case ARRAY_TYPE:
 144                         {
 145                                 array *compiled_data = data.as<array>().untagged();
 146                                 cell parameters = array_nth(compiled_data,0);
 147                                 cell literals = array_nth(compiled_data,1);
 148                                 cell relocation = array_nth(compiled_data,2);
 149                                 cell labels = array_nth(compiled_data,3);
 150                                 cell code = array_nth(compiled_data,4);
 151
 152                                 code_block *compiled = add_code_block(
 153                                         code_block_optimized,
 154                                         code,
 155                                         labels,
 156                                         word.value(),
 157                                         relocation,
 158                                         parameters,
 159                                         literals);
 160
 161                                 word->code = compiled;
 162                         }
 163                         break;
 164                 default:
 165                         critical_error("Expected a quotation or an array",data.value());
 166                         break;
 167                 }
 168
 169                 update_word_entry_point(word.untagged());
 170         }
 171
 172         if(update_existing_words)
 173                 update_code_heap_words(reset_inline_caches);
 174         else
 175                 initialize_code_blocks();
 176 }
 177
 178 code_heap_room factor_vm::code_room()
 179 {
 180         code_heap_room room;
 181
 182         room.size             = code->allocator->size;
 183         room.occupied_space   = code->allocator->occupied_space();
 184         room.total_free       = code->allocator->free_space();
 185         room.contiguous_free  = code->allocator->largest_free_block();
 186         room.free_block_count = code->allocator->free_block_count();
 187
 188         return room;
 189 }
 190
 191 void factor_vm::primitive_code_room()
 192 {
 193         code_heap_room room = code_room();
 194         ctx->push(tag<byte_array>(byte_array_from_value(&room)));
 195 }
 196
 197 struct stack_trace_stripper {
 198         explicit stack_trace_stripper() {}
 199
 200         void operator()(code_block *compiled, cell size)
 201         {
 202                 compiled->owner = false_object;
 203         }
 204 };
 205
 206 void factor_vm::primitive_strip_stack_traces()
 207 {
 208         stack_trace_stripper stripper;
 209         each_code_block(stripper);
 210 }
 211
 212 struct code_block_accumulator {
 213         std::vector<cell> objects;
 214
 215         void operator()(code_block *compiled, cell size)
 216         {
 217                 objects.push_back(compiled->owner);
 218                 objects.push_back(compiled->parameters);
 219                 objects.push_back(compiled->relocation);
 220
 221                 objects.push_back(tag_fixnum(compiled->type()));
 222                 objects.push_back(tag_fixnum(compiled->size()));
 223
 224                 /* Note: the entry point is always a multiple of the heap
 225                 alignment (16 bytes). We cannot allocate while iterating
 226                 through the code heap, so it is not possible to call
 227                 from_unsigned_cell() here. It is OK, however, to add it as
 228                 if it were a fixnum, and have library code shift it to the
 229                 left by 4. */
 230                 cell entry_point = (cell)compiled->entry_point();
 231                 assert((entry_point & (data_alignment - 1)) == 0);
 232                 assert((entry_point & TAG_MASK) == FIXNUM_TYPE);
 233                 objects.push_back(entry_point);
 234         }
 235 };
 236
 237 cell factor_vm::code_blocks()
 238 {
 239         code_block_accumulator accum;
 240         each_code_block(accum);
 241         return std_vector_to_array(accum.objects);
 242 }
 243
 244 void factor_vm::primitive_code_blocks()
 245 {
 246         ctx->push(code_blocks());
 247 }
 248
 249 }