vm/gc_info.hpp

   1 namespace factor {
   2
   3 // gc_info should be kept in sync with:
   4 //   basis/compiler/codegen/gc-maps/gc-maps.factor
   5 //   basis/vm/vm.factor
   6 struct gc_info {
   7   uint32_t scrub_d_count;
   8   uint32_t scrub_r_count;
   9   uint32_t gc_root_count;
  10   uint32_t derived_root_count;
  11   uint32_t return_address_count;
  12
  13   cell callsite_bitmap_size() {
  14     return scrub_d_count + scrub_r_count + gc_root_count;
  15   }
  16
  17   cell total_bitmap_size() {
  18     return return_address_count * callsite_bitmap_size();
  19   }
  20
  21   cell total_bitmap_bytes() { return ((total_bitmap_size() + 7) / 8); }
  22
  23   uint32_t* return_addresses() {
  24     return (uint32_t*)this - return_address_count;
  25   }
  26
  27   uint32_t* base_pointer_map() {
  28     return return_addresses() - return_address_count * derived_root_count;
  29   }
  30
  31   uint8_t* gc_info_bitmap() {
  32     return (uint8_t*)base_pointer_map() - total_bitmap_bytes();
  33   }
  34
  35   cell callsite_scrub_d(cell index) {
  36     cell base = 0;
  37     return base + index * scrub_d_count;
  38   }
  39
  40   cell callsite_scrub_r(cell index) {
  41     cell base = return_address_count * scrub_d_count;
  42     return base + index * scrub_r_count;
  43   }
  44
  45   cell callsite_gc_roots(cell index) {
  46     cell base =
  47         return_address_count * scrub_d_count +
  48         return_address_count * scrub_r_count;
  49     return base + index * gc_root_count;
  50   }
  51
  52   uint32_t lookup_base_pointer(cell index, cell derived_root) {
  53     return base_pointer_map()[index * derived_root_count + derived_root];
  54   }
  55
  56   cell return_address_index(cell return_address);
  57 };
  58
  59 }