Add allocation and garbage collection infrastructure.
Change-Id: I4b04cdfdf18afb75a7b0df87b509e8156b4a932b
diff --git a/src/object_bitmap.h b/src/object_bitmap.h
new file mode 100644
index 0000000..3e779b2
--- /dev/null
+++ b/src/object_bitmap.h
@@ -0,0 +1,138 @@
+// Copyright (C) 2008 The Android Open Source Project
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef ART_SRC_OBJECT_BITMAP_H_
+#define ART_SRC_OBJECT_BITMAP_H_
+
+#include <limits.h>
+#include <stdint.h>
+
+#include "src/globals.h"
+#include "src/logging.h"
+
+namespace art {
+
+class Object;
+
+// <offset> is the difference from .base to a pointer address.
+// <index> is the index of .bits that contains the bit representing
+// <offset>.
+#define HB_OFFSET_TO_INDEX(offset_) \
+ ((offset_) / kAlignment / kBitsPerWord)
+#define HB_INDEX_TO_OFFSET(index_) \
+ ((index_) * kAlignment * kBitsPerWord)
+
+#define HB_OFFSET_TO_BYTE_INDEX(offset_) \
+ (HB_OFFSET_TO_INDEX(offset_) * sizeof(*((HeapBitmap *)0)->words_))
+
+// Pack the bits in backwards so they come out in address order
+// when using CLZ.
+#define HB_OFFSET_TO_MASK(offset_) \
+ (1 << \
+ (31-(((uintptr_t)(offset_) / kAlignment) % kBitsPerWord)))
+
+class HeapBitmap {
+ public:
+ static const size_t kAlignment = 8;
+
+ typedef void Callback(Object *obj, void *arg);
+
+ typedef void ScanCallback(Object *obj, void *finger, void *arg);
+
+ typedef void SweepCallback(size_t numPtrs, void **ptrs, void *arg);
+
+ static HeapBitmap* Create(byte* base, size_t length);
+
+ ~HeapBitmap();
+
+ void Set(const Object* obj) {
+ Modify(obj, true);
+ }
+
+ void Clear(const Object* obj) {
+ Modify(obj, false);
+ }
+
+ void Clear();
+
+ bool Test(const Object* obj) {
+ CHECK(HasAddress(obj));
+ CHECK(words_ != NULL);
+ CHECK_GE((uintptr_t)obj, base_);
+ if ((uintptr_t)obj <= max_) {
+ const uintptr_t offset = (uintptr_t)obj - base_;
+ unsigned long word = words_[HB_OFFSET_TO_INDEX(offset)];
+ return (word & HB_OFFSET_TO_MASK(offset)) != 0;
+ } else {
+ return false;
+ }
+ }
+
+ bool HasAddress(const void* addr) const;
+
+ void Walk(Callback* callback, void* arg);
+
+ void ScanWalk(uintptr_t base, uintptr_t max,
+ ScanCallback* thunk, void* arg);
+
+ static void SweepWalk(const HeapBitmap& live,
+ const HeapBitmap& mark,
+ uintptr_t base, uintptr_t max,
+ SweepCallback* thunk, void* arg);
+
+ private:
+ HeapBitmap(const void* base, size_t length)
+ : words_(NULL),
+ num_bytes_(length),
+ base_(reinterpret_cast<uintptr_t>(base)) {
+ };
+
+ void Modify(const Object* obj, bool do_set) {
+ uintptr_t addr = reinterpret_cast<uintptr_t>(obj);
+ CHECK_GE(addr, base_);
+ const uintptr_t offset = addr - base_;
+ const size_t index = HB_OFFSET_TO_INDEX(offset);
+ const unsigned long mask = HB_OFFSET_TO_MASK(offset);
+ CHECK_LT(index, num_bytes_ / kWordSize);
+ if (do_set) {
+ if (addr > max_) {
+ max_ = addr;
+ }
+ words_[index] |= mask;
+ } else {
+ words_[index] &= ~mask;
+ }
+ }
+
+ bool Init(const byte* base, size_t length);
+
+ unsigned long* words_;
+
+ size_t num_bytes_;
+
+ // The base address, which corresponds to the word containing the
+ // first bit in the bitmap.
+ uintptr_t base_;
+
+ // The highest pointer value ever returned by an allocation from
+ // this heap. I.e., the highest address that may correspond to a
+ // set bit. If there are no bits set, (max < base).
+ uintptr_t max_;
+
+ const char* name_;
+};
+
+} // namespace art
+
+#endif // ART_SRC_OBJECT_BITMAP_H_