Fix off-by-1 error in new SpaceBitmap
Do not visit_end in the VisitMarkedRange code.
Change-Id: Iaf02788509b21a102cd1c0e2db3cbd09d0522bfa
diff --git a/runtime/gc/accounting/space_bitmap-inl.h b/runtime/gc/accounting/space_bitmap-inl.h
index 0fbd27c..880ff1f 100644
--- a/runtime/gc/accounting/space_bitmap-inl.h
+++ b/runtime/gc/accounting/space_bitmap-inl.h
@@ -58,6 +58,14 @@
void SpaceBitmap::VisitMarkedRange(uintptr_t visit_begin, uintptr_t visit_end,
const Visitor& visitor) const {
DCHECK_LT(visit_begin, visit_end);
+#if 0
+ for (uintptr_t i = visit_begin; i < visit_end; i += kAlignment) {
+ mirror::Object* obj = reinterpret_cast<mirror::Object*>(i);
+ if (Test(obj)) {
+ visitor(obj);
+ }
+ }
+#else
DCHECK_LE(heap_begin_, visit_begin);
DCHECK_LE(visit_end, HeapLimit());
@@ -114,14 +122,20 @@
}
// Right edge is unique.
- right_edge = bitmap_begin_[index_end];
+ // But maybe we don't have anything to do: visit_end starts in a new word...
+ if (bit_end == 0) {
+ // Do not read memory, as it could be after the end of the bitmap.
+ right_edge = 0;
+ } else {
+ right_edge = bitmap_begin_[index_end];
+ }
} else {
// Right edge = left edge.
right_edge = left_edge;
}
// Right edge handling.
- right_edge &= ((static_cast<uword>(1) << bit_end) - 1) | (static_cast<uword>(1) << bit_end);
+ right_edge &= ((static_cast<uword>(1) << bit_end) - 1);
if (right_edge != 0) {
const uintptr_t ptr_base = IndexToOffset(index_end) + heap_begin_;
do {
@@ -131,6 +145,7 @@
right_edge ^= (static_cast<uword>(1)) << shift;
} while (right_edge != 0);
}
+#endif
}
inline bool SpaceBitmap::Modify(const mirror::Object* obj, bool do_set) {