Each space has its own bitmap(s)
Each alloc space now has One mark+live bitmap. Each image space has only one live bitmap.
Change-Id: I2e919d1bd7d9f4d35d0e95ed83a58df6f754df6e
diff --git a/src/heap_bitmap.h b/src/heap_bitmap.h
index 34c11b9..e2109d6 100644
--- a/src/heap_bitmap.h
+++ b/src/heap_bitmap.h
@@ -1,5 +1,5 @@
/*
- * Copyright (C) 2008 The Android Open Source Project
+ * Copyright (C) 2012 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.
@@ -17,175 +17,65 @@
#ifndef ART_SRC_HEAP_BITMAP_H_
#define ART_SRC_HEAP_BITMAP_H_
-#include <limits.h>
-#include <stdint.h>
-
-#include "UniquePtr.h"
-#include "globals.h"
-#include "logging.h"
-#include "mem_map.h"
-#include "utils.h"
+#include "space_bitmap.h"
namespace art {
+ class Heap;
+ class SpaceBitmap;
-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(*(reinterpret_cast<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 ptr_count, Object** ptrs, void* arg);
-
- // Initialize a HeapBitmap so that it points to a bitmap large enough to cover a heap at
- // heap_begin of heap_capacity bytes, where objects are guaranteed to be kAlignment-aligned.
- static HeapBitmap* Create(const char* name, byte* heap_begin, size_t heap_capacity);
-
- ~HeapBitmap();
-
- inline void Set(const Object* obj) {
- Modify(obj, true);
- }
-
- inline void Clear(const Object* obj) {
- Modify(obj, false);
- }
-
- void Clear();
-
- inline bool Test(const Object* obj) {
- uintptr_t addr = reinterpret_cast<uintptr_t>(obj);
- DCHECK(HasAddress(obj)) << obj;
- DCHECK(bitmap_begin_ != NULL);
- DCHECK_GE(addr, heap_begin_);
- if (addr <= heap_end_) {
- const uintptr_t offset = addr - heap_begin_;
- return (bitmap_begin_[HB_OFFSET_TO_INDEX(offset)] & HB_OFFSET_TO_MASK(offset)) != 0;
- } else {
- return false;
- }
- }
-
- bool HasAddress(const void* addr) const;
-
- void VisitRange(uintptr_t base, uintptr_t max, Callback* visitor, void* arg) const;
-
- class ClearVisitor {
+ class HeapBitmap {
public:
- explicit ClearVisitor(HeapBitmap* const bitmap)
- : bitmap_(bitmap) {
+ bool Test(const Object* obj) {
+ SpaceBitmap* bitmap = GetSpaceBitmap(obj);
+ DCHECK(bitmap != NULL);
+ return bitmap->Test(obj);
}
- void operator ()(Object* obj) const {
- bitmap_->Clear(obj);
+ void Clear(const Object* obj) {
+ SpaceBitmap* bitmap = GetSpaceBitmap(obj);
+ DCHECK(bitmap != NULL)
+ << "tried to clear object "
+ << reinterpret_cast<const void*>(obj)
+ << " which did not belong to any bitmaps";
+ return bitmap->Clear(obj);
}
+
+ void Set(const Object* obj) {
+ SpaceBitmap* bitmap = GetSpaceBitmap(obj);
+ DCHECK(bitmap != NULL)
+ << "tried to mark object "
+ << reinterpret_cast<const void*>(obj)
+ << " which did not belong to any bitmaps";
+ bitmap->Set(obj);
+ }
+
+ SpaceBitmap* GetSpaceBitmap(const Object* obj) {
+ // TODO: C++0x auto
+ for (BitmapVec::iterator cur = bitmaps_.begin(); cur != bitmaps_.end(); ++cur) {
+ if ((*cur)->HasAddress(obj)) {
+ return *cur;
+ }
+ }
+ return NULL;
+ }
+
+ void Walk(SpaceBitmap::Callback* callback, void* arg) {
+ // TODO: C++0x auto
+ for (BitmapVec::iterator cur = bitmaps_.begin(); cur != bitmaps_.end(); ++cur) {
+ (*cur)->Walk(callback, arg);
+ }
+ }
+
private:
- HeapBitmap* const bitmap_;
+ void AddSpaceBitmap(SpaceBitmap* space) {
+ bitmaps_.push_back(space);
+ }
+
+ typedef std::vector<SpaceBitmap*> BitmapVec;
+ BitmapVec bitmaps_;
+
+ friend class Heap;
};
-
- template <typename Visitor>
- void VisitRange(uintptr_t visit_begin, uintptr_t visit_end, const Visitor& visitor) const {
- for (; visit_begin < visit_end; visit_begin += kAlignment ) {
- visitor(reinterpret_cast<Object*>(visit_begin));
- }
- }
-
- template <typename Visitor>
- void VisitMarkedRange(uintptr_t visit_begin, uintptr_t visit_end, const Visitor& visitor) const {
- size_t start = HB_OFFSET_TO_INDEX(visit_begin - heap_begin_);
- size_t end = HB_OFFSET_TO_INDEX(visit_end - heap_begin_ - 1);
- for (size_t i = start; i <= end; i++) {
- word w = bitmap_begin_[i];
- if (w != 0) {
- word high_bit = 1 << (kBitsPerWord - 1);
- uintptr_t ptr_base = HB_INDEX_TO_OFFSET(i) + heap_begin_;
- do {
- const int shift = CLZ(w);
- Object* obj = reinterpret_cast<Object*>(ptr_base + shift * kAlignment);
- visitor(obj);
- w &= ~(high_bit >> shift);
- } while (w != 0);
- }
- }
- }
-
- void Walk(Callback* callback, void* arg);
-
- void InOrderWalk(HeapBitmap::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:
- // TODO: heap_end_ is initialized so that the heap bitmap is empty, this doesn't require the -1,
- // however, we document that this is expected on heap_end_
- HeapBitmap(const char* name, MemMap* mem_map, word* bitmap_begin, size_t bitmap_size, const void* heap_begin)
- : mem_map_(mem_map), bitmap_begin_(bitmap_begin), bitmap_size_(bitmap_size),
- heap_begin_(reinterpret_cast<uintptr_t>(heap_begin)), heap_end_(heap_begin_ - 1),
- name_(name) {}
-
- inline void Modify(const Object* obj, bool do_set) {
- uintptr_t addr = reinterpret_cast<uintptr_t>(obj);
- DCHECK_GE(addr, heap_begin_);
- const uintptr_t offset = addr - heap_begin_;
- const size_t index = HB_OFFSET_TO_INDEX(offset);
- const word mask = HB_OFFSET_TO_MASK(offset);
- DCHECK_LT(index, bitmap_size_ / kWordSize);
- if (do_set) {
- if (addr > heap_end_) {
- heap_end_ = addr;
- }
- bitmap_begin_[index] |= mask;
- } else {
- bitmap_begin_[index] &= ~mask;
- }
- }
-
- // Backing storage for bitmap.
- UniquePtr<MemMap> mem_map_;
-
- // This bitmap itself, word sized for efficiency in scanning.
- word* const bitmap_begin_;
-
- // Size of this bitmap.
- const size_t bitmap_size_;
-
- // The base address of the heap, which corresponds to the word containing the first bit in the
- // bitmap.
- const uintptr_t heap_begin_;
-
- // 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, (heap_end_ < heap_begin_).
- uintptr_t heap_end_;
-
- // Name of this bitmap.
- const char* const name_;
-};
-
} // namespace art
#endif // ART_SRC_HEAP_BITMAP_H_