def test_invalidate_cache(self):
h = HeapCache()
h.setfield(box1, box2, descr1)
h.setarrayitem(box1, index1, box2, descr1)
h.setarrayitem(box1, index2, box4, descr1)
h.invalidate_caches(rop.INT_ADD, None, [])
h.invalidate_caches(rop.INT_ADD_OVF, None, [])
h.invalidate_caches(rop.SETFIELD_RAW, None, [])
h.invalidate_caches(rop.SETARRAYITEM_RAW, None, [])
assert h.getfield(box1, descr1) is box2
assert h.getarrayitem(box1, index1, descr1) is box2
assert h.getarrayitem(box1, index2, descr1) is box4
h.invalidate_caches(
rop.CALL, FakeCallDescr(FakeEffectinfo.EF_ELIDABLE_CANNOT_RAISE), [])
assert h.getfield(box1, descr1) is box2
assert h.getarrayitem(box1, index1, descr1) is box2
assert h.getarrayitem(box1, index2, descr1) is box4
h.invalidate_caches(rop.GUARD_TRUE, None, [])
assert h.getfield(box1, descr1) is box2
assert h.getarrayitem(box1, index1, descr1) is box2
assert h.getarrayitem(box1, index2, descr1) is box4
h.invalidate_caches(
rop.CALL_LOOPINVARIANT, FakeCallDescr(FakeEffectinfo.EF_LOOPINVARIANT), [])
h.invalidate_caches(
rop.CALL, FakeCallDescr(FakeEffectinfo.EF_RANDOM_EFFECTS), [])
assert h.getfield(box1, descr1) is None
assert h.getarrayitem(box1, index1, descr1) is None
assert h.getarrayitem(box1, index2, descr1) is None
def test_bug_heap_cache_is_cleared_but_not_is_unescaped_2(self):
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
h.new(box1)
h.new(box2)
h.setfield(box1, box2, descr1)
h.invalidate_caches(rop.SETFIELD_GC, None, [box1, box2])
assert h.getfield(box1, descr1) is box2
descr = BasicFailDescr()
class XTra:
oopspecindex = 0
OS_ARRAYCOPY = 42
extraeffect = 5
EF_LOOPINVARIANT = 1
EF_ELIDABLE_CANNOT_RAISE = 2
EF_ELIDABLE_OR_MEMORYERROR = 3
EF_ELIDABLE_CAN_RAISE = 4
descr.get_extra_info = XTra
h.invalidate_caches(rop.CALL_N, descr, [])
assert h.is_unescaped(box1)
assert h.is_unescaped(box2)
assert h.getfield(box1, descr1) is box2
def test_bug_heap_cache_is_cleared_but_not_is_unescaped_2(self):
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
h.new(box1)
h.new(box2)
h.setfield(box1, box2, descr1)
h.invalidate_caches(rop.SETFIELD_GC, None, [box1, box2])
assert h.getfield(box1, descr1) is box2
descr = BasicFailDescr()
class XTra:
oopspecindex = 0
OS_ARRAYCOPY = 42
OS_ARRAYMOVE = 49
extraeffect = 5
EF_LOOPINVARIANT = 1
EF_ELIDABLE_CANNOT_RAISE = 2
EF_ELIDABLE_OR_MEMORYERROR = 3
EF_ELIDABLE_CAN_RAISE = 4
descr.get_extra_info = XTra
h.invalidate_caches(rop.CALL_N, descr, [])
assert h.is_unescaped(box1)
assert h.is_unescaped(box2)
assert h.getfield(box1, descr1) is box2
def test_invalidate_cache(self):
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box4 = RefFrontendOp(4)
h.setfield(box1, box2, descr1)
h.setarrayitem(box1, index1, box2, descr1)
h.setarrayitem(box1, index2, box4, descr1)
h.invalidate_caches(rop.INT_ADD, None, [])
h.invalidate_caches(rop.INT_ADD_OVF, None, [])
h.invalidate_caches(rop.SETFIELD_RAW, None, [])
h.invalidate_caches(rop.SETARRAYITEM_RAW, None, [])
assert h.getfield(box1, descr1) is box2
assert h.getarrayitem(box1, index1, descr1) is box2
assert h.getarrayitem(box1, index2, descr1) is box4
h.invalidate_caches(
rop.CALL_N, FakeCallDescr(FakeEffectinfo.EF_ELIDABLE_CANNOT_RAISE), [])
assert h.getfield(box1, descr1) is box2
assert h.getarrayitem(box1, index1, descr1) is box2
assert h.getarrayitem(box1, index2, descr1) is box4
h.invalidate_caches(rop.GUARD_TRUE, None, [])
assert h.getfield(box1, descr1) is box2
assert h.getarrayitem(box1, index1, descr1) is box2
assert h.getarrayitem(box1, index2, descr1) is box4
h.invalidate_caches(
rop.CALL_LOOPINVARIANT_N, FakeCallDescr(FakeEffectinfo.EF_LOOPINVARIANT), [])
h.invalidate_caches(
rop.CALL_N, FakeCallDescr(FakeEffectinfo.EF_RANDOM_EFFECTS), [])
assert h.getfield(box1, descr1) is None
assert h.getarrayitem(box1, index1, descr1) is None
assert h.getarrayitem(box1, index2, descr1) is None
def test_replace_box_with_const(self):
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
c_box3 = ConstPtr(ConstPtr.value)
h.setfield(box1, box2, descr1)
h.setfield(box1, box3, descr2)
h.setfield(box2, box3, descr3)
h.replace_box(box3, c_box3)
assert h.getfield(box1, descr1) is box2
assert c_box3.same_constant(h.getfield(box1, descr2))
assert c_box3.same_constant(h.getfield(box2, descr3))
def test_replace_box_with_const(self):
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
c_box3 = ConstPtr(ConstPtr.value)
h.setfield(box1, box2, descr1)
h.setfield(box1, box3, descr2)
h.setfield(box2, box3, descr3)
h.replace_box(box3, c_box3)
assert h.getfield(box1, descr1) is box2
assert c_box3.same_constant(h.getfield(box1, descr2))
assert c_box3.same_constant(h.getfield(box2, descr3))
def test_heapcache_fields(self):
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is None
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is None
h.setfield(box1, box3, descr2)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is box3
h.setfield(box1, box3, descr1)
assert h.getfield(box1, descr1) is box3
assert h.getfield(box1, descr2) is box3
h.setfield(box3, box1, descr1)
assert h.getfield(box3, descr1) is box1
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is box3
h.reset()
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is None
assert h.getfield(box3, descr1) is None
def test_heapcache_fields(self):
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is None
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is None
h.setfield(box1, box3, descr2)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is box3
h.setfield(box1, box3, descr1)
assert h.getfield(box1, descr1) is box3
assert h.getfield(box1, descr2) is box3
h.setfield(box3, box1, descr1)
assert h.getfield(box3, descr1) is box1
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is box3
h.reset()
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is None
assert h.getfield(box3, descr1) is None
def test_heapcache_read_fields_multiple(self):
h = HeapCache()
h.getfield_now_known(box1, descr1, box2)
h.getfield_now_known(box3, descr1, box4)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is None
assert h.getfield(box3, descr1) is box4
assert h.getfield(box3, descr2) is None
h.reset()
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is None
assert h.getfield(box3, descr1) is None
assert h.getfield(box3, descr2) is None
def test_heapcache_read_fields_multiple(self):
h = HeapCache()
h.getfield_now_known(box1, descr1, box2)
h.getfield_now_known(box3, descr1, box4)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is None
assert h.getfield(box3, descr1) is box4
assert h.getfield(box3, descr2) is None
h.reset()
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is None
assert h.getfield(box3, descr1) is None
assert h.getfield(box3, descr2) is None
def test_bug_missing_ignored_operations(self):
h = HeapCache()
h.new(box1)
h.new(box2)
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.invalidate_caches(rop.STRSETITEM, None, [])
h.invalidate_caches(rop.UNICODESETITEM, None, [])
h.invalidate_caches(rop.SETFIELD_RAW, None, [])
h.invalidate_caches(rop.SETARRAYITEM_RAW, None, [])
h.invalidate_caches(rop.SETINTERIORFIELD_RAW, None, [])
h.invalidate_caches(rop.RAW_STORE, None, [])
assert h.is_unescaped(box1)
assert h.is_unescaped(box2)
assert h.getfield(box1, descr1) is box2
def test_bug_missing_ignored_operations(self):
h = HeapCache()
h.new(box1)
h.new(box2)
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.invalidate_caches(rop.STRSETITEM, None, [])
h.invalidate_caches(rop.UNICODESETITEM, None, [])
h.invalidate_caches(rop.SETFIELD_RAW, None, [])
h.invalidate_caches(rop.SETARRAYITEM_RAW, None, [])
h.invalidate_caches(rop.SETINTERIORFIELD_RAW, None, [])
h.invalidate_caches(rop.RAW_STORE, None, [])
assert h.is_unescaped(box1)
assert h.is_unescaped(box2)
assert h.getfield(box1, descr1) is box2
def test_replace_box_with_box(self):
py.test.skip("replacing a box with another box: not supported any more")
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
box4 = RefFrontendOp(4)
h.setfield(box1, box2, descr1)
h.setfield(box1, box3, descr2)
h.setfield(box2, box3, descr3)
h.replace_box(box1, box4)
assert h.getfield(box4, descr1) is box2
assert h.getfield(box4, descr2) is box3
assert h.getfield(box2, descr3) is box3
h.setfield(box4, box3, descr1)
assert h.getfield(box4, descr1) is box3
def test_call_doesnt_invalidate_unescaped_boxes(self):
h = HeapCache()
h.new(box1)
assert h.is_unescaped(box1)
h.setfield(box1, box2, descr1)
h.invalidate_caches(rop.CALL, FakeCallDescr(FakeEffectinfo.EF_CAN_RAISE), [])
assert h.getfield(box1, descr1) is box2
def test_replace_box_with_box(self):
py.test.skip("replacing a box with another box: not supported any more")
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
box4 = RefFrontendOp(4)
h.setfield(box1, box2, descr1)
h.setfield(box1, box3, descr2)
h.setfield(box2, box3, descr3)
h.replace_box(box1, box4)
assert h.getfield(box4, descr1) is box2
assert h.getfield(box4, descr2) is box3
assert h.getfield(box2, descr3) is box3
h.setfield(box4, box3, descr1)
assert h.getfield(box4, descr1) is box3
def test_call_doesnt_invalidate_unescaped_boxes(self):
h = HeapCache()
h.new(box1)
assert h.is_unescaped(box1)
h.setfield(box1, box2, descr1)
h.invalidate_caches(rop.CALL,
FakeCallDescr(FakeEffectinfo.EF_CAN_RAISE), [])
assert h.getfield(box1, descr1) is box2
def test_bug_heap_cache_is_cleared_but_not_is_unescaped_1(self):
# bug if only the getfield() link is cleared (heap_cache) but not
# the is_unescaped() flags: we can do later a GETFIELD(box1) which
# will give us a fresh box3, which is actually equal to box2. This
# box3 is escaped, but box2 is still unescaped. Bug shown e.g. by
# calling some residual code that changes the values on box3: then
# the content of box2 is still cached at the old value.
h = HeapCache()
h.new(box1)
h.new(box2)
h.setfield(box1, box2, descr1)
h.invalidate_caches(rop.SETFIELD_GC, None, [box1, box2])
assert h.getfield(box1, descr1) is box2
h.invalidate_caches(rop.CALL_MAY_FORCE, None, [])
assert not h.is_unescaped(box1)
assert not h.is_unescaped(box2)
assert h.getfield(box1, descr1) is None
def test_bug_heap_cache_is_cleared_but_not_is_unescaped_1(self):
# bug if only the getfield() link is cleared (heap_cache) but not
# the is_unescaped() flags: we can do later a GETFIELD(box1) which
# will give us a fresh box3, which is actually equal to box2. This
# box3 is escaped, but box2 is still unescaped. Bug shown e.g. by
# calling some residual code that changes the values on box3: then
# the content of box2 is still cached at the old value.
h = HeapCache()
h.new(box1)
h.new(box2)
h.setfield(box1, box2, descr1)
h.invalidate_caches(rop.SETFIELD_GC, None, [box1, box2])
assert h.getfield(box1, descr1) is box2
h.invalidate_caches(rop.CALL_MAY_FORCE, None, [])
assert not h.is_unescaped(box1)
assert not h.is_unescaped(box2)
assert h.getfield(box1, descr1) is None
def test_heapcache_write_fields_multiple(self):
h = HeapCache()
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.setfield(box3, box4, descr1)
assert h.getfield(box3, descr1) is box4
assert h.getfield(box1, descr1) is None # box1 and box3 can alias
h = HeapCache()
h.new(box1)
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.setfield(box3, box4, descr1)
assert h.getfield(box3, descr1) is box4
assert h.getfield(box1, descr1) is None # box1 and box3 can alias
h = HeapCache()
h.new(box1)
h.new(box3)
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.setfield(box3, box4, descr1)
assert h.getfield(box3, descr1) is box4
assert h.getfield(box1, descr1) is box2 # box1 and box3 cannot alias
h.setfield(box1, box3, descr1)
assert h.getfield(box1, descr1) is box3
def test_heapcache_write_fields_multiple(self):
h = HeapCache()
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.setfield(box3, box4, descr1)
assert h.getfield(box3, descr1) is box4
assert h.getfield(box1, descr1) is None # box1 and box3 can alias
h = HeapCache()
h.new(box1)
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.setfield(box3, box4, descr1)
assert h.getfield(box3, descr1) is box4
assert h.getfield(box1, descr1) is None # box1 and box3 can alias
h = HeapCache()
h.new(box1)
h.new(box3)
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.setfield(box3, box4, descr1)
assert h.getfield(box3, descr1) is box4
assert h.getfield(box1, descr1) is box2 # box1 and box3 cannot alias
h.setfield(box1, box3, descr1)
assert h.getfield(box1, descr1) is box3
def test_heapcache_read_fields_multiple(self):
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
box4 = RefFrontendOp(4)
h.getfield_now_known(box1, descr1, box2)
h.getfield_now_known(box3, descr1, box4)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is None
assert h.getfield(box3, descr1) is box4
assert h.getfield(box3, descr2) is None
h.reset()
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is None
assert h.getfield(box3, descr1) is None
assert h.getfield(box3, descr2) is None
def test_heapcache_read_fields_multiple(self):
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
box4 = RefFrontendOp(4)
h.getfield_now_known(box1, descr1, box2)
h.getfield_now_known(box3, descr1, box4)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is None
assert h.getfield(box3, descr1) is box4
assert h.getfield(box3, descr2) is None
h.reset()
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is None
assert h.getfield(box3, descr1) is None
assert h.getfield(box3, descr2) is None
def test_replace_box(self):
h = HeapCache()
h.setfield(box1, box2, descr1)
h.setfield(box1, box3, descr2)
h.setfield(box2, box3, descr3)
h.replace_box(box1, box4)
assert h.getfield(box4, descr1) is box2
assert h.getfield(box4, descr2) is box3
assert h.getfield(box2, descr3) is box3
h.setfield(box4, box3, descr1)
assert h.getfield(box4, descr1) is box3
h = HeapCache()
h.setfield(box1, box2, descr1)
h.setfield(box1, box3, descr2)
h.setfield(box2, box3, descr3)
h.replace_box(box3, box4)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is box4
assert h.getfield(box2, descr3) is box4
def test_replace_box(self):
h = HeapCache()
h.setfield(box1, box2, descr1)
h.setfield(box1, box3, descr2)
h.setfield(box2, box3, descr3)
h.replace_box(box1, box4)
assert h.getfield(box4, descr1) is box2
assert h.getfield(box4, descr2) is box3
assert h.getfield(box2, descr3) is box3
h.setfield(box4, box3, descr1)
assert h.getfield(box4, descr1) is box3
h = HeapCache()
h.setfield(box1, box2, descr1)
h.setfield(box1, box3, descr2)
h.setfield(box2, box3, descr3)
h.replace_box(box3, box4)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is box4
assert h.getfield(box2, descr3) is box4
def test_replace_box_twice(self):
py.test.skip("replacing a box with another box: not supported any more")
h = HeapCache()
h.setfield(box1, box2, descr1)
h.setfield(box1, box3, descr2)
h.setfield(box2, box3, descr3)
h.replace_box(box1, box4)
h.replace_box(box4, box5)
assert h.getfield(box5, descr1) is box2
assert h.getfield(box5, descr2) is box3
assert h.getfield(box2, descr3) is box3
h.setfield(box5, box3, descr1)
assert h.getfield(box4, descr1) is box3
h = HeapCache()
h.setfield(box1, box2, descr1)
h.setfield(box1, box3, descr2)
h.setfield(box2, box3, descr3)
h.replace_box(box3, box4)
h.replace_box(box4, box5)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is box5
assert h.getfield(box2, descr3) is box5
def test_replace_box_twice(self):
py.test.skip("replacing a box with another box: not supported any more")
h = HeapCache()
h.setfield(box1, box2, descr1)
h.setfield(box1, box3, descr2)
h.setfield(box2, box3, descr3)
h.replace_box(box1, box4)
h.replace_box(box4, box5)
assert h.getfield(box5, descr1) is box2
assert h.getfield(box5, descr2) is box3
assert h.getfield(box2, descr3) is box3
h.setfield(box5, box3, descr1)
assert h.getfield(box4, descr1) is box3
h = HeapCache()
h.setfield(box1, box2, descr1)
h.setfield(box1, box3, descr2)
h.setfield(box2, box3, descr3)
h.replace_box(box3, box4)
h.replace_box(box4, box5)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is box5
assert h.getfield(box2, descr3) is box5
def test_heapcache_fields(self):
h = HeapCache()
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is None
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is None
h.setfield(box1, box3, descr2)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is box3
h.setfield(box1, box3, descr1)
assert h.getfield(box1, descr1) is box3
assert h.getfield(box1, descr2) is box3
h.setfield(box3, box1, descr1)
assert h.getfield(box3, descr1) is box1
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is box3
h.reset()
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is None
assert h.getfield(box3, descr1) is None
def test_heapcache_fields(self):
h = HeapCache()
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is None
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is None
h.setfield(box1, box3, descr2)
assert h.getfield(box1, descr1) is box2
assert h.getfield(box1, descr2) is box3
h.setfield(box1, box3, descr1)
assert h.getfield(box1, descr1) is box3
assert h.getfield(box1, descr2) is box3
h.setfield(box3, box1, descr1)
assert h.getfield(box3, descr1) is box1
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is box3
h.reset()
assert h.getfield(box1, descr1) is None
assert h.getfield(box1, descr2) is None
assert h.getfield(box3, descr1) is None
def test_heapcache_write_fields_multiple(self):
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
box4 = RefFrontendOp(4)
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.setfield(box3, box4, descr1)
assert h.getfield(box3, descr1) is box4
assert h.getfield(box1, descr1) is None # box1 and box3 can alias
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
box4 = RefFrontendOp(4)
h.new(box1)
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.setfield(box3, box4, descr1)
assert h.getfield(box3, descr1) is box4
assert h.getfield(box1, descr1) is None # box1 and box3 can alias
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
box4 = RefFrontendOp(4)
h.new(box1)
h.new(box3)
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.setfield(box3, box4, descr1)
assert h.getfield(box3, descr1) is box4
assert h.getfield(box1, descr1) is box2 # box1 and box3 cannot alias
h.setfield(box1, box3, descr1)
assert h.getfield(box1, descr1) is box3
def test_heapcache_write_fields_multiple(self):
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
box4 = RefFrontendOp(4)
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.setfield(box3, box4, descr1)
assert h.getfield(box3, descr1) is box4
assert h.getfield(box1, descr1) is None # box1 and box3 can alias
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
box4 = RefFrontendOp(4)
h.new(box1)
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.setfield(box3, box4, descr1)
assert h.getfield(box3, descr1) is box4
assert h.getfield(box1, descr1) is None # box1 and box3 can alias
h = HeapCache()
box1 = RefFrontendOp(1)
box2 = RefFrontendOp(2)
box3 = RefFrontendOp(3)
box4 = RefFrontendOp(4)
h.new(box1)
h.new(box3)
h.setfield(box1, box2, descr1)
assert h.getfield(box1, descr1) is box2
h.setfield(box3, box4, descr1)
assert h.getfield(box3, descr1) is box4
assert h.getfield(box1, descr1) is box2 # box1 and box3 cannot alias
h.setfield(box1, box3, descr1)
assert h.getfield(box1, descr1) is box3
