tests/test_gc7.cc

   1 //////////////////////////////////////////////////////////////////////////////
   2 //  Testing the ability to trace cross heap pointers.
   3 //  We'll allocate a list in two different collectors.
   4 //  Garbage collection should preserve the shape of the list.
   5 //////////////////////////////////////////////////////////////////////////////
   6
   7 #include <iostream.h>
   8 #include <assert.h>
   9 #include <AD/gc/gc.h>
  10 #include <AD/gc/bgc.h>
  11 #include <AD/gc/gcobject.h>
  12 #include <AD/gc/gcheaps.h>
  13
  14 BGC heap1;
  15 BGC& heap2 = bgc;
  16
  17 #define TRIALS 5    // number of times to test
  18 #define LENGTH 100  // length of list to allocate
  19
  20 class LIST : public GCObject {
  21    int    tag;
  22    int    junk[500];
  23 public:
  24    LIST * next;
  25    LIST(LIST * n) : next(n)
  26      { for (int i = 0; i < 500; i++) junk[i] = i + tag; }
  27   ~LIST() {}
  28    void verify() const
  29    {  for (int i = 0; i < 500; i++) assert(junk[i] == i+tag);
  30       if (next) next->verify();
  31    }
  32    void trace(GC * gc) { next = (LIST*)gc->trace(next); }
  33 };
  34
  35 int length(LIST * l)
  36 {  int len;
  37    for (len = 0; l; l = l->next)
  38       len++;
  39    return len;
  40 }
  41
  42
  43 void do_something()
  44 {  LIST * l = 0;
  45    for (int i = 0; i < LENGTH; i++) {
  46       l = new (heap1) LIST(l);
  47           new (heap1) LIST(l);  // some garbage for heap1
  48           new (heap1) LIST(l);  // some garbage for heap1
  49           new (heap1) LIST(l);  // some garbage for heap1
  50       l = new (heap2) LIST(l);
  51           new (heap2) LIST(l);  // some garbage for heap2
  52           new (heap2) LIST(l);  // some garbage for heap2
  53           new (heap2) LIST(l);  // some garbage for heap2
  54    }
  55    l->verify();
  56    assert(length(l) == LENGTH * 2);
  57 }
  58
  59 int main()
  60 {
  61    cout << "Testing crossheap pointers\n";
  62    for (int trial = 1; trial <= TRIALS; trial++) {
  63       cout << "Trial " << trial << "\n" << flush;
  64       do_something();
  65       cout << "Trial " << trial << " has passed\n" << flush;
  66    }
  67    cout << "Now cleaning up\n";
  68    heap1.collect();
  69    heap2.collect();
  70    return 0;
  71 }