shotgun/lib/heap.h

   1 #ifndef RBS_HEAP_H
   2 #define RBS_HEAP_H
   3
   4 typedef void* address;
   5
   6 /*
   7  address : lower heap bound address
   8  curret  : current tip of the heap
   9  last    : upper heap bound address
  10  scan    : GC scanner position
  11  */
  12 struct heap {
  13   size_t size;
  14   address address;
  15   address current;
  16   address last;
  17   address scan;
  18 };
  19
  20 typedef struct heap* rheap;
  21
  22 rheap heap_new(size_t size);
  23 int heap_deallocate(rheap h);
  24 int heap_allocate_memory(rheap h);
  25 int heap_allocate_extended(rheap h);
  26 int heap_reset(rheap h);
  27 int heap_enough_fields_p(rheap h, int fields);
  28 int heap_allocated_p(rheap h);
  29 int heap_using_extended_p(rheap h);
  30 OBJECT heap_copy_object(rheap h, OBJECT obj);
  31 OBJECT heap_next_object(rheap h);
  32 int heap_fully_scanned_p(rheap h);
  33 OBJECT heap_next_unscanned(rheap h);
  34 int heap_enough_fields_p(rheap h, int fields);
  35
  36 /* controls fast heap allocation using inline functions on and off */
  37 #define FAST_HEAP 1
  38
  39 #ifdef FAST_HEAP
  40
  41 #include <string.h>
  42
  43 static inline address heap_allocate(rheap h, unsigned int size) {
  44   address addr;
  45   addr = (address)h->current;
  46   memset((void*)addr, 0, size);
  47   h->current = (address)((uintptr_t)h->current +  size);
  48
  49   return addr;
  50 }
  51
  52 #define heap_allocate_dirty(h, size) ({ \
  53       address _a; _a = (address)h->current; h->current = (address)((uintptr_t)h->current + size); _a; })
  54
  55 #define heap_putback(h, size) (h->current = (address)((uintptr_t)h->current - size))
  56
  57 static inline unsigned int heap_enough_space_p(rheap h, unsigned int size) {
  58   if((uintptr_t)h->current + size > (uintptr_t)h->last + 1) return FALSE;
  59   return TRUE;
  60 }
  61
  62 static inline unsigned int heap_contains_p(rheap h, address addr) {
  63
  64   if(addr < h->address) return FALSE;
  65   if(addr >= (address)((uintptr_t)h->last)) return FALSE;
  66   return TRUE;
  67 }
  68
  69
  70 #else
  71
  72 address heap_allocate(rheap h, unsigned int size);
  73 unsigned int heap_enough_space_p(rheap h, unsigned int size);
  74
  75 #endif
  76
  77 #endif